*/
#define SSH2_PKTCTX_DHGROUP 0x0001
#define SSH2_PKTCTX_DHGEX 0x0002
+#define SSH2_PKTCTX_KEX_MASK 0x000F
#define SSH2_PKTCTX_PUBLICKEY 0x0010
#define SSH2_PKTCTX_PASSWORD 0x0020
#define SSH2_PKTCTX_KBDINTER 0x0040
static const char *const ssh2_disconnect_reasons[] = {
NULL,
- "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
- "SSH_DISCONNECT_PROTOCOL_ERROR",
- "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
- "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
- "SSH_DISCONNECT_MAC_ERROR",
- "SSH_DISCONNECT_COMPRESSION_ERROR",
- "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
- "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
- "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
- "SSH_DISCONNECT_CONNECTION_LOST",
- "SSH_DISCONNECT_BY_APPLICATION",
- "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
- "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
- "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
- "SSH_DISCONNECT_ILLEGAL_USER_NAME",
+ "host not allowed to connect",
+ "protocol error",
+ "key exchange failed",
+ "host authentication failed",
+ "MAC error",
+ "compression error",
+ "service not available",
+ "protocol version not supported",
+ "host key not verifiable",
+ "connection lost",
+ "by application",
+ "too many connections",
+ "auth cancelled by user",
+ "no more auth methods available",
+ "illegal user name",
};
#define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
#define BUG_CHOKES_ON_RSA 8
#define BUG_SSH2_RSA_PADDING 16
#define BUG_SSH2_DERIVEKEY 32
-#define BUG_SSH2_DH_GEX 64
+#define BUG_SSH2_REKEY 64
#define BUG_SSH2_PK_SESSIONID 128
+/*
+ * Codes for terminal modes.
+ * Most of these are the same in SSH-1 and SSH-2.
+ * This list is derived from draft-ietf-secsh-connect-25 and
+ * SSH-1 RFC-1.2.31.
+ */
+static const struct {
+ const char* const mode;
+ int opcode;
+ enum { TTY_OP_CHAR, TTY_OP_BOOL } type;
+} ssh_ttymodes[] = {
+ /* "V" prefix discarded for special characters relative to SSH specs */
+ { "INTR", 1, TTY_OP_CHAR },
+ { "QUIT", 2, TTY_OP_CHAR },
+ { "ERASE", 3, TTY_OP_CHAR },
+ { "KILL", 4, TTY_OP_CHAR },
+ { "EOF", 5, TTY_OP_CHAR },
+ { "EOL", 6, TTY_OP_CHAR },
+ { "EOL2", 7, TTY_OP_CHAR },
+ { "START", 8, TTY_OP_CHAR },
+ { "STOP", 9, TTY_OP_CHAR },
+ { "SUSP", 10, TTY_OP_CHAR },
+ { "DSUSP", 11, TTY_OP_CHAR },
+ { "REPRINT", 12, TTY_OP_CHAR },
+ { "WERASE", 13, TTY_OP_CHAR },
+ { "LNEXT", 14, TTY_OP_CHAR },
+ { "FLUSH", 15, TTY_OP_CHAR },
+ { "SWTCH", 16, TTY_OP_CHAR },
+ { "STATUS", 17, TTY_OP_CHAR },
+ { "DISCARD", 18, TTY_OP_CHAR },
+ { "IGNPAR", 30, TTY_OP_BOOL },
+ { "PARMRK", 31, TTY_OP_BOOL },
+ { "INPCK", 32, TTY_OP_BOOL },
+ { "ISTRIP", 33, TTY_OP_BOOL },
+ { "INLCR", 34, TTY_OP_BOOL },
+ { "IGNCR", 35, TTY_OP_BOOL },
+ { "ICRNL", 36, TTY_OP_BOOL },
+ { "IUCLC", 37, TTY_OP_BOOL },
+ { "IXON", 38, TTY_OP_BOOL },
+ { "IXANY", 39, TTY_OP_BOOL },
+ { "IXOFF", 40, TTY_OP_BOOL },
+ { "IMAXBEL", 41, TTY_OP_BOOL },
+ { "ISIG", 50, TTY_OP_BOOL },
+ { "ICANON", 51, TTY_OP_BOOL },
+ { "XCASE", 52, TTY_OP_BOOL },
+ { "ECHO", 53, TTY_OP_BOOL },
+ { "ECHOE", 54, TTY_OP_BOOL },
+ { "ECHOK", 55, TTY_OP_BOOL },
+ { "ECHONL", 56, TTY_OP_BOOL },
+ { "NOFLSH", 57, TTY_OP_BOOL },
+ { "TOSTOP", 58, TTY_OP_BOOL },
+ { "IEXTEN", 59, TTY_OP_BOOL },
+ { "ECHOCTL", 60, TTY_OP_BOOL },
+ { "ECHOKE", 61, TTY_OP_BOOL },
+ { "PENDIN", 62, TTY_OP_BOOL }, /* XXX is this a real mode? */
+ { "OPOST", 70, TTY_OP_BOOL },
+ { "OLCUC", 71, TTY_OP_BOOL },
+ { "ONLCR", 72, TTY_OP_BOOL },
+ { "OCRNL", 73, TTY_OP_BOOL },
+ { "ONOCR", 74, TTY_OP_BOOL },
+ { "ONLRET", 75, TTY_OP_BOOL },
+ { "CS7", 90, TTY_OP_BOOL },
+ { "CS8", 91, TTY_OP_BOOL },
+ { "PARENB", 92, TTY_OP_BOOL },
+ { "PARODD", 93, TTY_OP_BOOL }
+};
+
+/* Miscellaneous other tty-related constants. */
+#define SSH_TTY_OP_END 0
+/* The opcodes for ISPEED/OSPEED differ between SSH-1 and SSH-2. */
+#define SSH1_TTY_OP_ISPEED 192
+#define SSH1_TTY_OP_OSPEED 193
+#define SSH2_TTY_OP_ISPEED 128
+#define SSH2_TTY_OP_OSPEED 129
+
+/* Helper functions for parsing tty-related config. */
+static unsigned int ssh_tty_parse_specchar(char *s)
+{
+ unsigned int ret;
+ if (*s) {
+ char *next = NULL;
+ ret = ctrlparse(s, &next);
+ if (!next) ret = s[0];
+ } else {
+ ret = 255; /* special value meaning "don't set" */
+ }
+ return ret;
+}
+static unsigned int ssh_tty_parse_boolean(char *s)
+{
+ if (stricmp(s, "yes") == 0 ||
+ stricmp(s, "on") == 0 ||
+ stricmp(s, "true") == 0 ||
+ stricmp(s, "+") == 0)
+ return 1; /* true */
+ else if (stricmp(s, "no") == 0 ||
+ stricmp(s, "off") == 0 ||
+ stricmp(s, "false") == 0 ||
+ stricmp(s, "-") == 0)
+ return 0; /* false */
+ else
+ return (atoi(s) != 0);
+}
+
#define translate(x) if (type == x) return #x
#define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
static char *ssh1_pkt_type(int type)
#undef translate
#undef translatec
-#define GET_32BIT(cp) \
- (((unsigned long)(unsigned char)(cp)[0] << 24) | \
- ((unsigned long)(unsigned char)(cp)[1] << 16) | \
- ((unsigned long)(unsigned char)(cp)[2] << 8) | \
- ((unsigned long)(unsigned char)(cp)[3]))
-
-#define PUT_32BIT(cp, value) { \
- (cp)[0] = (unsigned char)((value) >> 24); \
- (cp)[1] = (unsigned char)((value) >> 16); \
- (cp)[2] = (unsigned char)((value) >> 8); \
- (cp)[3] = (unsigned char)(value); }
-
/* Enumeration values for fields in SSH-1 packets */
enum {
PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM,
typedef struct ssh_tag *Ssh;
struct Packet;
+static struct Packet *ssh1_pkt_init(int pkt_type);
static struct Packet *ssh2_pkt_init(int pkt_type);
+static void ssh_pkt_ensure(struct Packet *, int length);
+static void ssh_pkt_adddata(struct Packet *, void *data, int len);
+static void ssh_pkt_addbyte(struct Packet *, unsigned char value);
static void ssh2_pkt_addbool(struct Packet *, unsigned char value);
-static void ssh2_pkt_adduint32(struct Packet *, unsigned long value);
-static void ssh2_pkt_addstring_start(struct Packet *);
-static void ssh2_pkt_addstring_str(struct Packet *, char *data);
-static void ssh2_pkt_addstring_data(struct Packet *, char *data, int len);
-static void ssh2_pkt_addstring(struct Packet *, char *data);
+static void ssh_pkt_adduint32(struct Packet *, unsigned long value);
+static void ssh_pkt_addstring_start(struct Packet *);
+static void ssh_pkt_addstring_str(struct Packet *, char *data);
+static void ssh_pkt_addstring_data(struct Packet *, char *data, int len);
+static void ssh_pkt_addstring(struct Packet *, char *data);
static unsigned char *ssh2_mpint_fmt(Bignum b, int *len);
+static void ssh1_pkt_addmp(struct Packet *, Bignum b);
static void ssh2_pkt_addmp(struct Packet *, Bignum b);
static int ssh2_pkt_construct(Ssh, struct Packet *);
static void ssh2_pkt_send(Ssh, struct Packet *);
*
* - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
* on a local data stream before we throttle the whole SSH
- * connection (in SSH1 only). Throttling the whole connection is
+ * connection (in SSH-1 only). Throttling the whole connection is
* pretty drastic so we set this high in the hope it won't
* happen very often.
*
* - SSH_MAX_BACKLOG is the amount of backlog that must build up
* on the SSH connection itself before we defensively throttle
* _all_ local data streams. This is pretty drastic too (though
- * thankfully unlikely in SSH2 since the window mechanism should
+ * thankfully unlikely in SSH-2 since the window mechanism should
* ensure that the server never has any need to throttle its end
* of the connection), so we set this high as well.
*
- * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
+ * - OUR_V2_WINSIZE is the maximum window size we present on SSH-2
* channels.
*/
#define SSH1_BUFFER_LIMIT 32768
#define SSH_MAX_BACKLOG 32768
#define OUR_V2_WINSIZE 16384
+#define OUR_V2_MAXPKT 0x4000UL
-const static struct ssh_kex *kex_algs[] = {
- &ssh_diffiehellman_gex,
- &ssh_diffiehellman_group14,
- &ssh_diffiehellman_group1,
-};
+/* Maximum length of passwords/passphrases (arbitrary) */
+#define SSH_MAX_PASSWORD_LEN 100
const static struct ssh_signkey *hostkey_algs[] = { &ssh_rsa, &ssh_dss };
-static void *nullmac_make_context(void)
-{
- return NULL;
-}
-static void nullmac_free_context(void *handle)
-{
-}
-static void nullmac_key(void *handle, unsigned char *key)
-{
-}
-static void nullmac_generate(void *handle, unsigned char *blk, int len,
- unsigned long seq)
-{
-}
-static int nullmac_verify(void *handle, unsigned char *blk, int len,
- unsigned long seq)
-{
- return 1;
-}
-const static struct ssh_mac ssh_mac_none = {
- nullmac_make_context, nullmac_free_context, nullmac_key,
- nullmac_generate, nullmac_verify, "none", 0
-};
const static struct ssh_mac *macs[] = {
- &ssh_sha1, &ssh_md5, &ssh_mac_none
+ &ssh_hmac_sha1, &ssh_hmac_sha1_96, &ssh_hmac_md5
};
const static struct ssh_mac *buggymacs[] = {
- &ssh_sha1_buggy, &ssh_md5, &ssh_mac_none
+ &ssh_hmac_sha1_buggy, &ssh_hmac_sha1_96_buggy, &ssh_hmac_md5
};
static void *ssh_comp_none_init(void)
Ssh ssh; /* pointer back to main context */
unsigned remoteid, localid;
int type;
+ /* True if we opened this channel but server hasn't confirmed. */
+ int halfopen;
/*
- * In SSH1, this value contains four bits:
+ * In SSH-1, this value contains four bits:
*
* 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
* 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
};
/*
- * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
- * 2 use this structure in different ways, reflecting SSH 2's
+ * 2-3-4 tree storing remote->local port forwardings. SSH-1 and SSH-2
+ * use this structure in different ways, reflecting SSH-2's
* altogether saner approach to port forwarding.
*
- * In SSH 1, you arrange a remote forwarding by sending the server
+ * In SSH-1, you arrange a remote forwarding by sending the server
* the remote port number, and the local destination host:port.
* When a connection comes in, the server sends you back that
* host:port pair, and you connect to it. This is a ready-made
* host:port pairs we _are_ trying to forward to, and reject a
* connection request from the server if it's not in the list.
*
- * In SSH 2, each side of the connection minds its own business and
+ * In SSH-2, each side of the connection minds its own business and
* doesn't send unnecessary information to the other. You arrange a
* remote forwarding by sending the server just the remote port
* number. When a connection comes in, the server tells you which
* of its ports was connected to; and _you_ have to remember what
* local host:port pair went with that port number.
*
- * Hence: in SSH 1 this structure stores host:port pairs we intend
- * to allow connections to, and is indexed by those host:port
- * pairs. In SSH 2 it stores a mapping from source port to
- * destination host:port pair, and is indexed by source port.
+ * Hence, in SSH-1 this structure is indexed by destination
+ * host:port pair, whereas in SSH-2 it is indexed by source port.
*/
+struct ssh_portfwd; /* forward declaration */
+
struct ssh_rportfwd {
unsigned sport, dport;
char dhost[256];
+ char *sportdesc;
+ struct ssh_portfwd *pfrec;
};
+#define free_rportfwd(pf) ( \
+ ((pf) ? (sfree((pf)->sportdesc)) : (void)0 ), sfree(pf) )
-struct Packet {
- long length;
+/*
+ * Separately to the rportfwd tree (which is for looking up port
+ * open requests from the server), a tree of _these_ structures is
+ * used to keep track of all the currently open port forwardings,
+ * so that we can reconfigure in mid-session if the user requests
+ * it.
+ */
+struct ssh_portfwd {
+ enum { DESTROY, KEEP, CREATE } status;
int type;
- unsigned long sequence;
- unsigned char *data;
- unsigned char *body;
- long savedpos;
- long maxlen;
- long encrypted_len; /* for SSH2 total-size counting */
+ unsigned sport, dport;
+ char *saddr, *daddr;
+ char *sserv, *dserv;
+ struct ssh_rportfwd *remote;
+ int addressfamily;
+ void *local;
+};
+#define free_portfwd(pf) ( \
+ ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr), \
+ sfree((pf)->sserv), sfree((pf)->dserv)) : (void)0 ), sfree(pf) )
+
+struct Packet {
+ long length; /* length of `data' actually used */
+ long forcepad; /* SSH-2: force padding to at least this length */
+ int type; /* only used for incoming packets */
+ unsigned long sequence; /* SSH-2 incoming sequence number */
+ unsigned char *data; /* allocated storage */
+ unsigned char *body; /* offset of payload within `data' */
+ long savedpos; /* temporary index into `data' (for strings) */
+ long maxlen; /* amount of storage allocated for `data' */
+ long encrypted_len; /* for SSH-2 total-size counting */
/*
* State associated with packet logging
struct logblank_t *blanks;
};
-static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen,
+static void ssh1_protocol(Ssh ssh, void *vin, int inlen,
struct Packet *pktin);
-static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen,
+static void ssh2_protocol(Ssh ssh, void *vin, int inlen,
struct Packet *pktin);
static void ssh1_protocol_setup(Ssh ssh);
static void ssh2_protocol_setup(Ssh ssh);
static void ssh_throttle_all(Ssh ssh, int enable, int bufsize);
static void ssh2_set_window(struct ssh_channel *c, unsigned newwin);
static int ssh_sendbuffer(void *handle);
-static void ssh_do_close(Ssh ssh);
+static int ssh_do_close(Ssh ssh, int notify_exit);
static unsigned long ssh_pkt_getuint32(struct Packet *pkt);
static int ssh2_pkt_getbool(struct Packet *pkt);
static void ssh_pkt_getstring(struct Packet *pkt, char **p, int *length);
static void ssh2_timer(void *ctx, long now);
-static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
+static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
struct Packet *pktin);
struct rdpkt1_state_tag {
};
typedef void (*handler_fn_t)(Ssh ssh, struct Packet *pktin);
+typedef void (*chandler_fn_t)(Ssh ssh, struct Packet *pktin, void *ctx);
+
+struct queued_handler;
+struct queued_handler {
+ int msg1, msg2;
+ chandler_fn_t handler;
+ void *ctx;
+ struct queued_handler *next;
+};
struct ssh_tag {
const struct plug_function_table *fn;
/* the above field _must_ be first in the structure */
- SHA_State exhash, exhashbase;
+ char *v_c, *v_s;
+ void *exhash;
Socket s;
void *cs_comp_ctx, *sc_comp_ctx;
const struct ssh_kex *kex;
const struct ssh_signkey *hostkey;
- unsigned char v2_session_id[20];
+ unsigned char v2_session_id[32];
+ int v2_session_id_len;
void *kex_ctx;
char *savedhost;
tree234 *channels; /* indexed by local id */
struct ssh_channel *mainchan; /* primary session channel */
int exitcode;
+ int close_expected;
+ int clean_exit;
- tree234 *rportfwds;
+ tree234 *rportfwds, *portfwds;
enum {
SSH_STATE_PREPACKET,
*/
int fallback_cmd;
- /*
- * Used for username and password input.
- */
- char *userpass_input_buffer;
- int userpass_input_buflen;
- int userpass_input_bufpos;
- int userpass_input_echo;
+ bufchain banner; /* accumulates banners during do_ssh2_authconn */
- char *portfwd_strptr;
int pkt_ctx;
void *x11auth;
int overall_bufsize;
int throttled_all;
int v1_stdout_throttling;
- int v2_outgoing_sequence;
+ unsigned long v2_outgoing_sequence;
int ssh1_rdpkt_crstate;
int ssh2_rdpkt_crstate;
struct rdpkt1_state_tag rdpkt1_state;
struct rdpkt2_state_tag rdpkt2_state;
- /* ssh1 and ssh2 use this for different things, but both use it */
+ /* SSH-1 and SSH-2 use this for different things, but both use it */
int protocol_initial_phase_done;
- void (*protocol) (Ssh ssh, unsigned char *in, int inlen,
+ void (*protocol) (Ssh ssh, void *vin, int inlen,
struct Packet *pkt);
struct Packet *(*s_rdpkt) (Ssh ssh, unsigned char **data, int *datalen);
Config cfg;
/*
- * Used to transfer data back from async agent callbacks.
+ * Used to transfer data back from async callbacks.
*/
void *agent_response;
int agent_response_len;
+ int user_response;
+
+ /*
+ * The SSH connection can be set as `frozen', meaning we are
+ * not currently accepting incoming data from the network. This
+ * is slightly more serious than setting the _socket_ as
+ * frozen, because we may already have had data passed to us
+ * from the network which we need to delay processing until
+ * after the freeze is lifted, so we also need a bufchain to
+ * store that data.
+ */
+ int frozen;
+ bufchain queued_incoming_data;
/*
* Dispatch table for packet types that we may have to deal
handler_fn_t packet_dispatch[256];
/*
+ * Queues of one-off handler functions for success/failure
+ * indications from a request.
+ */
+ struct queued_handler *qhead, *qtail;
+
+ /*
* This module deals with sending keepalives.
*/
Pinger pinger;
* size-based rekeys.
*/
unsigned long incoming_data_size, outgoing_data_size, deferred_data_size;
+ unsigned long max_data_size;
int kex_in_progress;
- long next_rekey;
+ long next_rekey, last_rekey;
+ char *deferred_rekey_reason; /* points to STATIC string; don't free */
};
-#define MAX_DATA_BEFORE_REKEY (0x40000000UL)
-#define REKEY_TIMEOUT (3600 * TICKSPERSEC)
-
#define logevent(s) logevent(ssh->frontend, s)
/* logevent, only printf-formatted. */
#define bombout(msg) \
do { \
char *text = dupprintf msg; \
- ssh_do_close(ssh); \
+ ssh_do_close(ssh, FALSE); \
logevent(text); \
connection_fatal(ssh->frontend, "%s", text); \
sfree(text); \
pkt->logmode = PKTLOG_EMIT;
}
+/* Helper function for common bits of parsing cfg.ttymodes. */
+static void parse_ttymodes(Ssh ssh, char *modes,
+ void (*do_mode)(void *data, char *mode, char *val),
+ void *data)
+{
+ while (*modes) {
+ char *t = strchr(modes, '\t');
+ char *m = snewn(t-modes+1, char);
+ char *val;
+ strncpy(m, modes, t-modes);
+ m[t-modes] = '\0';
+ if (*(t+1) == 'A')
+ val = get_ttymode(ssh->frontend, m);
+ else
+ val = dupstr(t+2);
+ if (val)
+ do_mode(data, m, val);
+ sfree(m);
+ sfree(val);
+ modes += strlen(modes) + 1;
+ }
+}
+
static int ssh_channelcmp(void *av, void *bv)
{
struct ssh_channel *a = (struct ssh_channel *) av;
return 0;
}
+/*
+ * Special form of strcmp which can cope with NULL inputs. NULL is
+ * defined to sort before even the empty string.
+ */
+static int nullstrcmp(const char *a, const char *b)
+{
+ if (a == NULL && b == NULL)
+ return 0;
+ if (a == NULL)
+ return -1;
+ if (b == NULL)
+ return +1;
+ return strcmp(a, b);
+}
+
+static int ssh_portcmp(void *av, void *bv)
+{
+ struct ssh_portfwd *a = (struct ssh_portfwd *) av;
+ struct ssh_portfwd *b = (struct ssh_portfwd *) bv;
+ int i;
+ if (a->type > b->type)
+ return +1;
+ if (a->type < b->type)
+ return -1;
+ if (a->addressfamily > b->addressfamily)
+ return +1;
+ if (a->addressfamily < b->addressfamily)
+ return -1;
+ if ( (i = nullstrcmp(a->saddr, b->saddr)) != 0)
+ return i < 0 ? -1 : +1;
+ if (a->sport > b->sport)
+ return +1;
+ if (a->sport < b->sport)
+ return -1;
+ if (a->type != 'D') {
+ if ( (i = nullstrcmp(a->daddr, b->daddr)) != 0)
+ return i < 0 ? -1 : +1;
+ if (a->dport > b->dport)
+ return +1;
+ if (a->dport < b->dport)
+ return -1;
+ }
+ return 0;
+}
+
static int alloc_channel_id(Ssh ssh)
{
const unsigned CHANNEL_NUMBER_OFFSET = 256;
return low + 1 + CHANNEL_NUMBER_OFFSET;
}
+static void c_write_stderr(int trusted, const char *buf, int len)
+{
+ int i;
+ for (i = 0; i < len; i++)
+ if (buf[i] != '\r' && (trusted || buf[i] & 0x60))
+ fputc(buf[i], stderr);
+}
+
static void c_write(Ssh ssh, const char *buf, int len)
{
- if ((flags & FLAG_STDERR)) {
- int i;
- for (i = 0; i < len; i++)
- if (buf[i] != '\r')
- fputc(buf[i], stderr);
- return;
- }
- from_backend(ssh->frontend, 1, buf, len);
+ if (flags & FLAG_STDERR)
+ c_write_stderr(1, buf, len);
+ else
+ from_backend(ssh->frontend, 1, buf, len);
}
static void c_write_untrusted(Ssh ssh, const char *buf, int len)
{
- int i;
- for (i = 0; i < len; i++) {
- if (buf[i] == '\n')
- c_write(ssh, "\r\n", 2);
- else if ((buf[i] & 0x60) || (buf[i] == '\r'))
- c_write(ssh, buf + i, 1);
- }
+ if (flags & FLAG_STDERR)
+ c_write_stderr(0, buf, len);
+ else
+ from_backend_untrusted(ssh->frontend, buf, len);
}
static void c_write_str(Ssh ssh, const char *buf)
{
struct Packet *pkt = snew(struct Packet);
- pkt->data = NULL;
+ pkt->body = pkt->data = NULL;
pkt->maxlen = 0;
pkt->logmode = PKTLOG_EMIT;
pkt->nblanks = 0;
* _Completely_ silly lengths should be stomped on before they
* do us any more damage.
*/
- if (st->len < 0 || st->pad < 0 || st->len + st->pad < 0) {
+ if (st->len < 0 || st->len > 35000 || st->pad < 4 ||
+ st->len - st->pad < 1 || (st->len + 4) % st->cipherblk != 0) {
bombout(("Incoming packet was garbled on decryption"));
ssh_free_packet(st->pktin);
crStop(NULL);
crFinish(st->pktin);
}
-static void ssh1_pktout_size(struct Packet *pkt, int len)
-{
- int pad, biglen;
-
- len += 5; /* type and CRC */
- pad = 8 - (len % 8);
- biglen = len + pad;
-
- pkt->length = len - 5;
- if (pkt->maxlen < biglen) {
- pkt->maxlen = biglen;
- pkt->data = sresize(pkt->data, biglen + 4 + APIEXTRA, unsigned char);
- }
- pkt->body = pkt->data + 4 + pad + 1;
-}
-
-static struct Packet *s_wrpkt_start(int type, int len)
-{
- struct Packet *pkt = ssh_new_packet();
- ssh1_pktout_size(pkt, len);
- pkt->type = type;
- /* Initialise log omission state */
- pkt->nblanks = 0;
- pkt->blanks = NULL;
- return pkt;
-}
-
-static int s_wrpkt_prepare(Ssh ssh, struct Packet *pkt)
+static int s_wrpkt_prepare(Ssh ssh, struct Packet *pkt, int *offset_p)
{
- int pad, biglen, i;
+ int pad, biglen, i, pktoffs;
unsigned long crc;
#ifdef __SC__
/*
#endif
int len;
- pkt->body[-1] = pkt->type;
-
if (ssh->logctx)
- log_packet(ssh->logctx, PKT_OUTGOING, pkt->type,
- ssh1_pkt_type(pkt->type),
- pkt->body, pkt->length,
+ log_packet(ssh->logctx, PKT_OUTGOING, pkt->data[12],
+ ssh1_pkt_type(pkt->data[12]),
+ pkt->body, pkt->length - (pkt->body - pkt->data),
pkt->nblanks, pkt->blanks);
sfree(pkt->blanks); pkt->blanks = NULL;
pkt->nblanks = 0;
unsigned char *compblk;
int complen;
zlib_compress_block(ssh->cs_comp_ctx,
- pkt->body - 1, pkt->length + 1,
+ pkt->data + 12, pkt->length - 12,
&compblk, &complen);
- ssh1_pktout_size(pkt, complen - 1);
- memcpy(pkt->body - 1, compblk, complen);
+ memcpy(pkt->data + 12, compblk, complen);
sfree(compblk);
+ pkt->length = complen + 12;
}
- len = pkt->length + 5; /* type and CRC */
+ ssh_pkt_ensure(pkt, pkt->length + 4); /* space for CRC */
+ pkt->length += 4;
+ len = pkt->length - 4 - 8; /* len(type+data+CRC) */
pad = 8 - (len % 8);
- biglen = len + pad;
+ pktoffs = 8 - pad;
+ biglen = len + pad; /* len(padding+type+data+CRC) */
- for (i = 0; i < pad; i++)
- pkt->data[i + 4] = random_byte();
- crc = crc32_compute(pkt->data + 4, biglen - 4);
- PUT_32BIT(pkt->data + biglen, crc);
- PUT_32BIT(pkt->data, len);
+ for (i = pktoffs; i < 4+8; i++)
+ pkt->data[i] = random_byte();
+ crc = crc32_compute(pkt->data + pktoffs + 4, biglen - 4); /* all ex len */
+ PUT_32BIT(pkt->data + pktoffs + 4 + biglen - 4, crc);
+ PUT_32BIT(pkt->data + pktoffs, len);
if (ssh->cipher)
- ssh->cipher->encrypt(ssh->v1_cipher_ctx, pkt->data + 4, biglen);
+ ssh->cipher->encrypt(ssh->v1_cipher_ctx,
+ pkt->data + pktoffs + 4, biglen);
- return biglen + 4;
+ if (offset_p) *offset_p = pktoffs;
+ return biglen + 4; /* len(length+padding+type+data+CRC) */
}
static void s_wrpkt(Ssh ssh, struct Packet *pkt)
{
- int len, backlog;
- len = s_wrpkt_prepare(ssh, pkt);
- backlog = sk_write(ssh->s, (char *)pkt->data, len);
+ int len, backlog, offset;
+ len = s_wrpkt_prepare(ssh, pkt, &offset);
+ backlog = sk_write(ssh->s, (char *)pkt->data + offset, len);
if (backlog > SSH_MAX_BACKLOG)
ssh_throttle_all(ssh, 1, backlog);
+ ssh_free_packet(pkt);
}
static void s_wrpkt_defer(Ssh ssh, struct Packet *pkt)
{
- int len;
- len = s_wrpkt_prepare(ssh, pkt);
+ int len, offset;
+ len = s_wrpkt_prepare(ssh, pkt, &offset);
if (ssh->deferred_len + len > ssh->deferred_size) {
ssh->deferred_size = ssh->deferred_len + len + 128;
ssh->deferred_send_data = sresize(ssh->deferred_send_data,
ssh->deferred_size,
unsigned char);
}
- memcpy(ssh->deferred_send_data + ssh->deferred_len, pkt->data, len);
+ memcpy(ssh->deferred_send_data + ssh->deferred_len,
+ pkt->data + offset, len);
ssh->deferred_len += len;
+ ssh_free_packet(pkt);
}
/*
- * Construct a packet with the specified contents.
+ * Construct a SSH-1 packet with the specified contents.
+ * (This all-at-once interface used to be the only one, but now SSH-1
+ * packets can also be constructed incrementally.)
*/
-static struct Packet *construct_packet(Ssh ssh, int pkttype,
- va_list ap1, va_list ap2)
+static struct Packet *construct_packet(Ssh ssh, int pkttype, va_list ap)
{
- unsigned char *p, *argp, argchar;
- unsigned long argint;
- int pktlen, argtype, arglen;
+ int argtype;
Bignum bn;
struct Packet *pkt;
- pktlen = 0;
- while ((argtype = va_arg(ap1, int)) != PKT_END) {
- switch (argtype) {
- case PKT_INT:
- (void) va_arg(ap1, int);
- pktlen += 4;
- break;
- case PKT_CHAR:
- (void) va_arg(ap1, int);
- pktlen++;
- break;
- case PKT_DATA:
- (void) va_arg(ap1, unsigned char *);
- arglen = va_arg(ap1, int);
- pktlen += arglen;
- break;
- case PKT_STR:
- argp = va_arg(ap1, unsigned char *);
- arglen = strlen((char *)argp);
- pktlen += 4 + arglen;
- break;
- case PKT_BIGNUM:
- bn = va_arg(ap1, Bignum);
- pktlen += ssh1_bignum_length(bn);
- break;
- case PKTT_PASSWORD:
- case PKTT_DATA:
- case PKTT_OTHER:
- /* ignore this pass */
- break;
- default:
- assert(0);
- }
- }
-
- pkt = s_wrpkt_start(pkttype, pktlen);
- p = pkt->body;
+ pkt = ssh1_pkt_init(pkttype);
- while ((argtype = va_arg(ap2, int)) != PKT_END) {
- int offset = p - pkt->body, len = 0;
+ while ((argtype = va_arg(ap, int)) != PKT_END) {
+ unsigned char *argp, argchar;
+ unsigned long argint;
+ int arglen;
switch (argtype) {
/* Actual fields in the packet */
case PKT_INT:
- argint = va_arg(ap2, int);
- PUT_32BIT(p, argint);
- len = 4;
+ argint = va_arg(ap, int);
+ ssh_pkt_adduint32(pkt, argint);
break;
case PKT_CHAR:
- argchar = (unsigned char) va_arg(ap2, int);
- *p = argchar;
- len = 1;
+ argchar = (unsigned char) va_arg(ap, int);
+ ssh_pkt_addbyte(pkt, argchar);
break;
case PKT_DATA:
- argp = va_arg(ap2, unsigned char *);
- arglen = va_arg(ap2, int);
- memcpy(p, argp, arglen);
- len = arglen;
+ argp = va_arg(ap, unsigned char *);
+ arglen = va_arg(ap, int);
+ ssh_pkt_adddata(pkt, argp, arglen);
break;
case PKT_STR:
- argp = va_arg(ap2, unsigned char *);
- arglen = strlen((char *)argp);
- PUT_32BIT(p, arglen);
- memcpy(p + 4, argp, arglen);
- len = arglen + 4;
+ argp = va_arg(ap, unsigned char *);
+ ssh_pkt_addstring(pkt, argp);
break;
case PKT_BIGNUM:
- bn = va_arg(ap2, Bignum);
- len = ssh1_write_bignum(p, bn);
+ bn = va_arg(ap, Bignum);
+ ssh1_pkt_addmp(pkt, bn);
break;
/* Tokens for modifications to packet logging */
case PKTT_PASSWORD:
end_log_omission(ssh, pkt);
break;
}
- p += len;
- /* Deal with logfile omission, if required. */
- if (len && (pkt->logmode != PKTLOG_EMIT)) {
- pkt->nblanks++;
- pkt->blanks = sresize(pkt->blanks, pkt->nblanks,
- struct logblank_t);
- pkt->blanks[pkt->nblanks-1].offset = offset;
- pkt->blanks[pkt->nblanks-1].len = len;
- pkt->blanks[pkt->nblanks-1].type = pkt->logmode;
- }
}
return pkt;
static void send_packet(Ssh ssh, int pkttype, ...)
{
struct Packet *pkt;
- va_list ap1, ap2;
- va_start(ap1, pkttype);
- va_start(ap2, pkttype);
- pkt = construct_packet(ssh, pkttype, ap1, ap2);
- va_end(ap2);
- va_end(ap1);
+ va_list ap;
+ va_start(ap, pkttype);
+ pkt = construct_packet(ssh, pkttype, ap);
+ va_end(ap);
s_wrpkt(ssh, pkt);
- ssh_free_packet(pkt);
}
static void defer_packet(Ssh ssh, int pkttype, ...)
{
struct Packet *pkt;
- va_list ap1, ap2;
- va_start(ap1, pkttype);
- va_start(ap2, pkttype);
- pkt = construct_packet(ssh, pkttype, ap1, ap2);
- va_end(ap2);
- va_end(ap1);
+ va_list ap;
+ va_start(ap, pkttype);
+ pkt = construct_packet(ssh, pkttype, ap);
+ va_end(ap);
s_wrpkt_defer(ssh, pkt);
- ssh_free_packet(pkt);
}
static int ssh_versioncmp(char *a, char *b)
/*
* Utility routines for putting an SSH-protocol `string' and
- * `uint32' into a SHA state.
+ * `uint32' into a hash state.
*/
-#include <stdio.h>
-static void sha_string(SHA_State * s, void *str, int len)
+static void hash_string(const struct ssh_hash *h, void *s, void *str, int len)
{
unsigned char lenblk[4];
PUT_32BIT(lenblk, len);
- SHA_Bytes(s, lenblk, 4);
- SHA_Bytes(s, str, len);
+ h->bytes(s, lenblk, 4);
+ h->bytes(s, str, len);
}
-static void sha_uint32(SHA_State * s, unsigned i)
+static void hash_uint32(const struct ssh_hash *h, void *s, unsigned i)
{
unsigned char intblk[4];
PUT_32BIT(intblk, i);
- SHA_Bytes(s, intblk, 4);
+ h->bytes(s, intblk, 4);
}
/*
- * SSH2 packet construction functions.
+ * Packet construction functions. Mostly shared between SSH-1 and SSH-2.
*/
-static void ssh2_pkt_ensure(struct Packet *pkt, int length)
+static void ssh_pkt_ensure(struct Packet *pkt, int length)
{
if (pkt->maxlen < length) {
+ unsigned char *body = pkt->body;
+ int offset = body ? body - pkt->data : 0;
pkt->maxlen = length + 256;
pkt->data = sresize(pkt->data, pkt->maxlen + APIEXTRA, unsigned char);
+ if (body) pkt->body = pkt->data + offset;
}
}
-static void ssh2_pkt_adddata(struct Packet *pkt, void *data, int len)
+static void ssh_pkt_adddata(struct Packet *pkt, void *data, int len)
{
if (pkt->logmode != PKTLOG_EMIT) {
pkt->nblanks++;
pkt->blanks = sresize(pkt->blanks, pkt->nblanks, struct logblank_t);
- pkt->blanks[pkt->nblanks-1].offset = pkt->length - 6;
+ assert(pkt->body);
+ pkt->blanks[pkt->nblanks-1].offset = pkt->length -
+ (pkt->body - pkt->data);
pkt->blanks[pkt->nblanks-1].len = len;
pkt->blanks[pkt->nblanks-1].type = pkt->logmode;
}
pkt->length += len;
- ssh2_pkt_ensure(pkt, pkt->length);
+ ssh_pkt_ensure(pkt, pkt->length);
memcpy(pkt->data + pkt->length - len, data, len);
}
-static void ssh2_pkt_addbyte(struct Packet *pkt, unsigned char byte)
-{
- ssh2_pkt_adddata(pkt, &byte, 1);
-}
-static struct Packet *ssh2_pkt_init(int pkt_type)
+static void ssh_pkt_addbyte(struct Packet *pkt, unsigned char byte)
{
- struct Packet *pkt = ssh_new_packet();
- pkt->length = 5;
- ssh2_pkt_addbyte(pkt, (unsigned char) pkt_type);
- return pkt;
+ ssh_pkt_adddata(pkt, &byte, 1);
}
static void ssh2_pkt_addbool(struct Packet *pkt, unsigned char value)
{
- ssh2_pkt_adddata(pkt, &value, 1);
+ ssh_pkt_adddata(pkt, &value, 1);
}
-static void ssh2_pkt_adduint32(struct Packet *pkt, unsigned long value)
+static void ssh_pkt_adduint32(struct Packet *pkt, unsigned long value)
{
unsigned char x[4];
PUT_32BIT(x, value);
- ssh2_pkt_adddata(pkt, x, 4);
+ ssh_pkt_adddata(pkt, x, 4);
}
-static void ssh2_pkt_addstring_start(struct Packet *pkt)
+static void ssh_pkt_addstring_start(struct Packet *pkt)
{
- ssh2_pkt_adduint32(pkt, 0);
+ ssh_pkt_adduint32(pkt, 0);
pkt->savedpos = pkt->length;
}
-static void ssh2_pkt_addstring_str(struct Packet *pkt, char *data)
+static void ssh_pkt_addstring_str(struct Packet *pkt, char *data)
{
- ssh2_pkt_adddata(pkt, data, strlen(data));
+ ssh_pkt_adddata(pkt, data, strlen(data));
PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos);
}
-static void ssh2_pkt_addstring_data(struct Packet *pkt, char *data, int len)
+static void ssh_pkt_addstring_data(struct Packet *pkt, char *data, int len)
{
- ssh2_pkt_adddata(pkt, data, len);
+ ssh_pkt_adddata(pkt, data, len);
PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos);
}
-static void ssh2_pkt_addstring(struct Packet *pkt, char *data)
+static void ssh_pkt_addstring(struct Packet *pkt, char *data)
{
- ssh2_pkt_addstring_start(pkt);
- ssh2_pkt_addstring_str(pkt, data);
+ ssh_pkt_addstring_start(pkt);
+ ssh_pkt_addstring_str(pkt, data);
+}
+static void ssh1_pkt_addmp(struct Packet *pkt, Bignum b)
+{
+ int len = ssh1_bignum_length(b);
+ unsigned char *data = snewn(len, char);
+ (void) ssh1_write_bignum(data, b);
+ ssh_pkt_adddata(pkt, data, len);
+ sfree(data);
}
static unsigned char *ssh2_mpint_fmt(Bignum b, int *len)
{
unsigned char *p;
int i, n = (bignum_bitcount(b) + 7) / 8;
p = snewn(n + 1, unsigned char);
- if (!p)
- fatalbox("out of memory");
p[0] = 0;
for (i = 1; i <= n; i++)
p[i] = bignum_byte(b, n - i);
unsigned char *p;
int len;
p = ssh2_mpint_fmt(b, &len);
- ssh2_pkt_addstring_start(pkt);
- ssh2_pkt_addstring_data(pkt, (char *)p, len);
+ ssh_pkt_addstring_start(pkt);
+ ssh_pkt_addstring_data(pkt, (char *)p, len);
sfree(p);
}
+static struct Packet *ssh1_pkt_init(int pkt_type)
+{
+ struct Packet *pkt = ssh_new_packet();
+ pkt->length = 4 + 8; /* space for length + max padding */
+ ssh_pkt_addbyte(pkt, pkt_type);
+ pkt->body = pkt->data + pkt->length;
+ return pkt;
+}
+
+/* For legacy code (SSH-1 and -2 packet construction used to be separate) */
+#define ssh2_pkt_ensure(pkt, length) ssh_pkt_ensure(pkt, length)
+#define ssh2_pkt_adddata(pkt, data, len) ssh_pkt_adddata(pkt, data, len)
+#define ssh2_pkt_addbyte(pkt, byte) ssh_pkt_addbyte(pkt, byte)
+#define ssh2_pkt_adduint32(pkt, value) ssh_pkt_adduint32(pkt, value)
+#define ssh2_pkt_addstring_start(pkt) ssh_pkt_addstring_start(pkt)
+#define ssh2_pkt_addstring_str(pkt, data) ssh_pkt_addstring_str(pkt, data)
+#define ssh2_pkt_addstring_data(pkt, data, len) ssh_pkt_addstring_data(pkt, data, len)
+#define ssh2_pkt_addstring(pkt, data) ssh_pkt_addstring(pkt, data)
+
+static struct Packet *ssh2_pkt_init(int pkt_type)
+{
+ struct Packet *pkt = ssh_new_packet();
+ pkt->length = 5; /* space for packet length + padding length */
+ pkt->forcepad = 0;
+ ssh_pkt_addbyte(pkt, (unsigned char) pkt_type);
+ pkt->body = pkt->data + pkt->length; /* after packet type */
+ return pkt;
+}
+
/*
- * Construct an SSH2 final-form packet: compress it, encrypt it,
+ * Construct an SSH-2 final-form packet: compress it, encrypt it,
* put the MAC on it. Final packet, ready to be sent, is stored in
* pkt->data. Total length is returned.
*/
if (ssh->logctx)
log_packet(ssh->logctx, PKT_OUTGOING, pkt->data[5],
ssh2_pkt_type(ssh->pkt_ctx, pkt->data[5]),
- pkt->data + 6, pkt->length - 6,
+ pkt->body, pkt->length - (pkt->body - pkt->data),
pkt->nblanks, pkt->blanks);
sfree(pkt->blanks); pkt->blanks = NULL;
pkt->nblanks = 0;
/*
* Add padding. At least four bytes, and must also bring total
* length (minus MAC) up to a multiple of the block size.
+ * If pkt->forcepad is set, make sure the packet is at least that size
+ * after padding.
*/
cipherblk = ssh->cscipher ? ssh->cscipher->blksize : 8; /* block size */
cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
padding = 4;
+ if (pkt->length + padding < pkt->forcepad)
+ padding = pkt->forcepad - pkt->length;
padding +=
(cipherblk - (pkt->length + padding) % cipherblk) % cipherblk;
+ assert(padding <= 255);
maclen = ssh->csmac ? ssh->csmac->len : 0;
ssh2_pkt_ensure(pkt, pkt->length + padding + maclen);
pkt->data[4] = padding;
* ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
* these or get queued, and then when the queue is later emptied
* the packets are all passed to defer_noqueue().
+ *
+ * When using a CBC-mode cipher, it's necessary to ensure that an
+ * attacker can't provide data to be encrypted using an IV that they
+ * know. We ensure this by prefixing each packet that might contain
+ * user data with an SSH_MSG_IGNORE. This is done using the deferral
+ * mechanism, so in this case send_noqueue() ends up redirecting to
+ * defer_noqueue(). If you don't like this inefficiency, don't use
+ * CBC.
*/
+static void ssh2_pkt_defer_noqueue(Ssh, struct Packet *, int);
+static void ssh_pkt_defersend(Ssh);
+
/*
- * Send an SSH2 packet immediately, without queuing or deferring.
+ * Send an SSH-2 packet immediately, without queuing or deferring.
*/
static void ssh2_pkt_send_noqueue(Ssh ssh, struct Packet *pkt)
{
int len;
int backlog;
+ if (ssh->cscipher != NULL && (ssh->cscipher->flags & SSH_CIPHER_IS_CBC)) {
+ /* We need to send two packets, so use the deferral mechanism. */
+ ssh2_pkt_defer_noqueue(ssh, pkt, FALSE);
+ ssh_pkt_defersend(ssh);
+ return;
+ }
len = ssh2_pkt_construct(ssh, pkt);
backlog = sk_write(ssh->s, (char *)pkt->data, len);
if (backlog > SSH_MAX_BACKLOG)
ssh->outgoing_data_size += pkt->encrypted_len;
if (!ssh->kex_in_progress &&
- ssh->outgoing_data_size > MAX_DATA_BEFORE_REKEY)
- do_ssh2_transport(ssh, "Initiating key re-exchange "
- "(too much data sent)", -1, NULL);
+ ssh->max_data_size != 0 &&
+ ssh->outgoing_data_size > ssh->max_data_size)
+ do_ssh2_transport(ssh, "too much data sent", -1, NULL);
ssh_free_packet(pkt);
}
/*
- * Defer an SSH2 packet.
+ * Defer an SSH-2 packet.
*/
-static void ssh2_pkt_defer_noqueue(Ssh ssh, struct Packet *pkt)
+static void ssh2_pkt_defer_noqueue(Ssh ssh, struct Packet *pkt, int noignore)
{
- int len = ssh2_pkt_construct(ssh, pkt);
+ int len;
+ if (ssh->cscipher != NULL && (ssh->cscipher->flags & SSH_CIPHER_IS_CBC) &&
+ ssh->deferred_len == 0 && !noignore) {
+ /*
+ * Interpose an SSH_MSG_IGNORE to ensure that user data don't
+ * get encrypted with a known IV.
+ */
+ struct Packet *ipkt = ssh2_pkt_init(SSH2_MSG_IGNORE);
+ ssh2_pkt_defer_noqueue(ssh, ipkt, TRUE);
+ }
+ len = ssh2_pkt_construct(ssh, pkt);
if (ssh->deferred_len + len > ssh->deferred_size) {
ssh->deferred_size = ssh->deferred_len + len + 128;
ssh->deferred_send_data = sresize(ssh->deferred_send_data,
}
/*
- * Queue an SSH2 packet.
+ * Queue an SSH-2 packet.
*/
static void ssh2_pkt_queue(Ssh ssh, struct Packet *pkt)
{
ssh2_pkt_send_noqueue(ssh, pkt);
}
+#if 0 /* disused */
/*
* Either queue or defer a packet, depending on whether queueing is
* set.
if (ssh->queueing)
ssh2_pkt_queue(ssh, pkt);
else
- ssh2_pkt_defer_noqueue(ssh, pkt);
+ ssh2_pkt_defer_noqueue(ssh, pkt, FALSE);
}
+#endif
/*
* Send the whole deferred data block constructed by
- * ssh2_pkt_defer() or SSH1's defer_packet().
+ * ssh2_pkt_defer() or SSH-1's defer_packet().
*
* The expected use of the defer mechanism is that you call
* ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
ssh->outgoing_data_size += ssh->deferred_data_size;
if (!ssh->kex_in_progress &&
- ssh->outgoing_data_size > MAX_DATA_BEFORE_REKEY)
- do_ssh2_transport(ssh, "Initiating key re-exchange "
- "(too much data sent)", -1, NULL);
+ ssh->max_data_size != 0 &&
+ ssh->outgoing_data_size > ssh->max_data_size)
+ do_ssh2_transport(ssh, "too much data sent", -1, NULL);
ssh->deferred_data_size = 0;
}
/*
- * Send all queued SSH2 packets. We send them by means of
+ * Send all queued SSH-2 packets. We send them by means of
* ssh2_pkt_defer_noqueue(), in case they included a pair of
* packets that needed to be lumped together.
*/
assert(!ssh->queueing);
for (i = 0; i < ssh->queuelen; i++)
- ssh2_pkt_defer_noqueue(ssh, ssh->queue[i]);
+ ssh2_pkt_defer_noqueue(ssh, ssh->queue[i], FALSE);
ssh->queuelen = 0;
ssh_pkt_defersend(ssh);
}
#endif
-static void sha_mpint(SHA_State * s, Bignum b)
+static void hash_mpint(const struct ssh_hash *h, void *s, Bignum b)
{
unsigned char *p;
int len;
p = ssh2_mpint_fmt(b, &len);
- sha_string(s, p, len);
+ hash_string(h, s, p, len);
sfree(p);
}
/*
- * Packet decode functions for both SSH1 and SSH2.
+ * Packet decode functions for both SSH-1 and SSH-2.
*/
static unsigned long ssh_pkt_getuint32(struct Packet *pkt)
{
}
/*
- * Helper function to add an SSH2 signature blob to a packet.
+ * Helper function to add an SSH-2 signature blob to a packet.
* Expects to be shown the public key blob as well as the signature
* blob. Normally works just like ssh2_pkt_addstring, but will
* fiddle with the signature packet if necessary for
* sniffing.
*/
ssh->remote_bugs |= BUG_CHOKES_ON_SSH1_IGNORE;
- logevent("We believe remote version has SSH1 ignore bug");
+ logevent("We believe remote version has SSH-1 ignore bug");
}
if (ssh->cfg.sshbug_plainpw1 == FORCE_ON ||
* the password.
*/
ssh->remote_bugs |= BUG_NEEDS_SSH1_PLAIN_PASSWORD;
- logevent("We believe remote version needs a plain SSH1 password");
+ logevent("We believe remote version needs a plain SSH-1 password");
}
if (ssh->cfg.sshbug_rsa1 == FORCE_ON ||
* an AUTH_RSA message.
*/
ssh->remote_bugs |= BUG_CHOKES_ON_RSA;
- logevent("We believe remote version can't handle RSA authentication");
+ logevent("We believe remote version can't handle SSH-1 RSA authentication");
}
if (ssh->cfg.sshbug_hmac2 == FORCE_ON ||
* These versions have the HMAC bug.
*/
ssh->remote_bugs |= BUG_SSH2_HMAC;
- logevent("We believe remote version has SSH2 HMAC bug");
+ logevent("We believe remote version has SSH-2 HMAC bug");
}
if (ssh->cfg.sshbug_derivekey2 == FORCE_ON ||
* generate the keys).
*/
ssh->remote_bugs |= BUG_SSH2_DERIVEKEY;
- logevent("We believe remote version has SSH2 key-derivation bug");
+ logevent("We believe remote version has SSH-2 key-derivation bug");
}
if (ssh->cfg.sshbug_rsapad2 == FORCE_ON ||
(wc_match("OpenSSH_2.[5-9]*", imp) ||
wc_match("OpenSSH_3.[0-2]*", imp)))) {
/*
- * These versions have the SSH2 RSA padding bug.
+ * These versions have the SSH-2 RSA padding bug.
*/
ssh->remote_bugs |= BUG_SSH2_RSA_PADDING;
- logevent("We believe remote version has SSH2 RSA padding bug");
+ logevent("We believe remote version has SSH-2 RSA padding bug");
}
if (ssh->cfg.sshbug_pksessid2 == FORCE_ON ||
(ssh->cfg.sshbug_pksessid2 == AUTO &&
wc_match("OpenSSH_2.[0-2]*", imp))) {
/*
- * These versions have the SSH2 session-ID bug in
+ * These versions have the SSH-2 session-ID bug in
* public-key authentication.
*/
ssh->remote_bugs |= BUG_SSH2_PK_SESSIONID;
- logevent("We believe remote version has SSH2 public-key-session-ID bug");
- }
-
- if (ssh->cfg.sshbug_dhgex2 == FORCE_ON) {
+ logevent("We believe remote version has SSH-2 public-key-session-ID bug");
+ }
+
+ if (ssh->cfg.sshbug_rekey2 == FORCE_ON ||
+ (ssh->cfg.sshbug_rekey2 == AUTO &&
+ (wc_match("DigiSSH_2.0", imp) ||
+ wc_match("OpenSSH_2.[0-4]*", imp) ||
+ wc_match("OpenSSH_2.5.[0-3]*", imp) ||
+ wc_match("Sun_SSH_1.0", imp) ||
+ wc_match("Sun_SSH_1.0.1", imp) ||
+ /* All versions <= 1.2.6 (they changed their format in 1.2.7) */
+ wc_match("WeOnlyDo-*", imp)))) {
/*
- * User specified the SSH2 DH GEX bug.
+ * These versions have the SSH-2 rekey bug.
*/
- ssh->remote_bugs |= BUG_SSH2_DH_GEX;
- logevent("We believe remote version has SSH2 DH group exchange bug");
+ ssh->remote_bugs |= BUG_SSH2_REKEY;
+ logevent("We believe remote version has SSH-2 rekey bug");
}
}
crBegin(ssh->do_ssh_init_crstate);
- /* Search for the string "SSH-" in the input. */
- s->i = 0;
- while (1) {
- static const int transS[] = { 1, 2, 2, 1 };
- static const int transH[] = { 0, 0, 3, 0 };
- static const int transminus[] = { 0, 0, 0, -1 };
- if (c == 'S')
- s->i = transS[s->i];
- else if (c == 'H')
- s->i = transH[s->i];
- else if (c == '-')
- s->i = transminus[s->i];
- else
- s->i = 0;
- if (s->i < 0)
- break;
- crReturn(1); /* get another character */
+ /* Search for a line beginning with the string "SSH-" in the input. */
+ for (;;) {
+ if (c != 'S') goto no;
+ crReturn(1);
+ if (c != 'S') goto no;
+ crReturn(1);
+ if (c != 'H') goto no;
+ crReturn(1);
+ if (c != '-') goto no;
+ break;
+ no:
+ while (c != '\012')
+ crReturn(1);
+ crReturn(1);
}
s->vstrsize = 16;
s->vstring[s->vslen] = 0;
s->vstring[strcspn(s->vstring, "\015\012")] = '\0';/* remove EOL chars */
- {
- char *vlog;
- vlog = snewn(20 + s->vslen, char);
- sprintf(vlog, "Server version: %s", s->vstring);
- logevent(vlog);
- sfree(vlog);
- }
+ logeventf(ssh, "Server version: %s", s->vstring);
ssh_detect_bugs(ssh, s->vstring);
/*
ssh_fix_verstring(verstring);
if (ssh->version == 2) {
+ size_t len;
/*
* Hash our version string and their version string.
*/
- SHA_Init(&ssh->exhashbase);
- sha_string(&ssh->exhashbase, verstring,
- strcspn(verstring, "\015\012"));
- sha_string(&ssh->exhashbase, s->vstring,
- strcspn(s->vstring, "\015\012"));
-
+ len = strcspn(verstring, "\015\012");
+ ssh->v_c = snewn(len + 1, char);
+ memcpy(ssh->v_c, verstring, len);
+ ssh->v_c[len] = 0;
+ len = strcspn(s->vstring, "\015\012");
+ ssh->v_s = snewn(len + 1, char);
+ memcpy(ssh->v_s, s->vstring, len);
+ ssh->v_s[len] = 0;
+
/*
- * Initialise SSHv2 protocol.
+ * Initialise SSH-2 protocol.
*/
ssh->protocol = ssh2_protocol;
ssh2_protocol_setup(ssh);
ssh->s_rdpkt = ssh2_rdpkt;
} else {
/*
- * Initialise SSHv1 protocol.
+ * Initialise SSH-1 protocol.
*/
ssh->protocol = ssh1_protocol;
ssh1_protocol_setup(ssh);
strcspn(verstring, "\015\012"), verstring);
sk_write(ssh->s, verstring, strlen(verstring));
sfree(verstring);
+ if (ssh->version == 2)
+ do_ssh2_transport(ssh, NULL, -1, NULL);
}
logeventf(ssh, "Using SSH protocol version %d", ssh->version);
crFinish(0);
}
+static void ssh_process_incoming_data(Ssh ssh,
+ unsigned char **data, int *datalen)
+{
+ struct Packet *pktin = ssh->s_rdpkt(ssh, data, datalen);
+ if (pktin) {
+ ssh->protocol(ssh, NULL, 0, pktin);
+ ssh_free_packet(pktin);
+ }
+}
+
+static void ssh_queue_incoming_data(Ssh ssh,
+ unsigned char **data, int *datalen)
+{
+ bufchain_add(&ssh->queued_incoming_data, *data, *datalen);
+ *data += *datalen;
+ *datalen = 0;
+}
+
+static void ssh_process_queued_incoming_data(Ssh ssh)
+{
+ void *vdata;
+ unsigned char *data;
+ int len, origlen;
+
+ while (!ssh->frozen && bufchain_size(&ssh->queued_incoming_data)) {
+ bufchain_prefix(&ssh->queued_incoming_data, &vdata, &len);
+ data = vdata;
+ origlen = len;
+
+ while (!ssh->frozen && len > 0)
+ ssh_process_incoming_data(ssh, &data, &len);
+
+ if (origlen > len)
+ bufchain_consume(&ssh->queued_incoming_data, origlen - len);
+ }
+}
+
+static void ssh_set_frozen(Ssh ssh, int frozen)
+{
+ if (ssh->s)
+ sk_set_frozen(ssh->s, frozen);
+ ssh->frozen = frozen;
+}
+
static void ssh_gotdata(Ssh ssh, unsigned char *data, int datalen)
{
crBegin(ssh->ssh_gotdata_crstate);
* everything to s_rdpkt, and then pass the resulting packets
* to the proper protocol handler.
*/
- if (datalen == 0)
- crReturnV;
+
while (1) {
- while (datalen > 0) {
- struct Packet *pktin = ssh->s_rdpkt(ssh, &data, &datalen);
- if (pktin) {
- ssh->protocol(ssh, NULL, 0, pktin);
- ssh_free_packet(pktin);
+ while (bufchain_size(&ssh->queued_incoming_data) > 0 || datalen > 0) {
+ if (ssh->frozen) {
+ ssh_queue_incoming_data(ssh, &data, &datalen);
+ /* This uses up all data and cannot cause anything interesting
+ * to happen; indeed, for anything to happen at all, we must
+ * return, so break out. */
+ break;
+ } else if (bufchain_size(&ssh->queued_incoming_data) > 0) {
+ /* This uses up some or all data, and may freeze the
+ * session. */
+ ssh_process_queued_incoming_data(ssh);
+ } else {
+ /* This uses up some or all data, and may freeze the
+ * session. */
+ ssh_process_incoming_data(ssh, &data, &datalen);
}
+ /* FIXME this is probably EBW. */
if (ssh->state == SSH_STATE_CLOSED)
return;
}
+ /* We're out of data. Go and get some more. */
crReturnV;
}
crFinishV;
}
-static void ssh_do_close(Ssh ssh)
+static int ssh_do_close(Ssh ssh, int notify_exit)
{
- int i;
+ int ret = 0;
struct ssh_channel *c;
ssh->state = SSH_STATE_CLOSED;
+ expire_timer_context(ssh);
if (ssh->s) {
sk_close(ssh->s);
ssh->s = NULL;
- notify_remote_exit(ssh->frontend);
+ if (notify_exit)
+ notify_remote_exit(ssh->frontend);
+ else
+ ret = 1;
}
/*
- * Now we must shut down any port and X forwardings going
+ * Now we must shut down any port- and X-forwarded channels going
* through this connection.
*/
if (ssh->channels) {
- for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
+ while (NULL != (c = index234(ssh->channels, 0))) {
switch (c->type) {
case CHAN_X11:
x11_close(c->u.x11.s);
pfd_close(c->u.pfd.s);
break;
}
- del234(ssh->channels, c);
+ del234(ssh->channels, c); /* moving next one to index 0 */
if (ssh->version == 2)
bufchain_clear(&c->v.v2.outbuffer);
sfree(c);
}
}
+ /*
+ * Go through port-forwardings, and close any associated
+ * listening sockets.
+ */
+ if (ssh->portfwds) {
+ struct ssh_portfwd *pf;
+ while (NULL != (pf = index234(ssh->portfwds, 0))) {
+ /* Dispose of any listening socket. */
+ if (pf->local)
+ pfd_terminate(pf->local);
+ del234(ssh->portfwds, pf); /* moving next one to index 0 */
+ free_portfwd(pf);
+ }
+ }
+
+ return ret;
+}
+
+static void ssh_log(Plug plug, int type, SockAddr addr, int port,
+ const char *error_msg, int error_code)
+{
+ Ssh ssh = (Ssh) plug;
+ char addrbuf[256], *msg;
+
+ sk_getaddr(addr, addrbuf, lenof(addrbuf));
+
+ if (type == 0)
+ msg = dupprintf("Connecting to %s port %d", addrbuf, port);
+ else
+ msg = dupprintf("Failed to connect to %s: %s", addrbuf, error_msg);
+
+ logevent(msg);
+ sfree(msg);
}
static int ssh_closing(Plug plug, const char *error_msg, int error_code,
int calling_back)
{
Ssh ssh = (Ssh) plug;
- ssh_do_close(ssh);
- if (error_msg) {
- /* A socket error has occurred. */
+ int need_notify = ssh_do_close(ssh, FALSE);
+
+ if (!error_msg) {
+ if (!ssh->close_expected)
+ error_msg = "Server unexpectedly closed network connection";
+ else
+ error_msg = "Server closed network connection";
+ }
+
+ if (need_notify)
+ notify_remote_exit(ssh->frontend);
+
+ if (error_msg)
logevent(error_msg);
+ if (!ssh->close_expected || !ssh->clean_exit)
connection_fatal(ssh->frontend, "%s", error_msg);
- } else {
- /* Otherwise, the remote side closed the connection normally. */
- }
return 0;
}
Ssh ssh = (Ssh) plug;
ssh_gotdata(ssh, (unsigned char *)data, len);
if (ssh->state == SSH_STATE_CLOSED) {
- ssh_do_close(ssh);
+ ssh_do_close(ssh, TRUE);
return 0;
}
return 1;
char **realhost, int nodelay, int keepalive)
{
static const struct plug_function_table fn_table = {
+ ssh_log,
ssh_closing,
ssh_receive,
ssh_sent,
const char *err;
ssh->savedhost = snewn(1 + strlen(host), char);
- if (!ssh->savedhost)
- fatalbox("Out of memory");
strcpy(ssh->savedhost, host);
if (port < 0)
/*
* Try to find host.
*/
- logeventf(ssh, "Looking up host \"%s\"", host);
- addr = name_lookup(host, port, realhost, &ssh->cfg);
+ logeventf(ssh, "Looking up host \"%s\"%s", host,
+ (ssh->cfg.addressfamily == ADDRTYPE_IPV4 ? " (IPv4)" :
+ (ssh->cfg.addressfamily == ADDRTYPE_IPV6 ? " (IPv6)" : "")));
+ addr = name_lookup(host, port, realhost, &ssh->cfg,
+ ssh->cfg.addressfamily);
if ((err = sk_addr_error(addr)) != NULL) {
sk_addr_free(addr);
return err;
/*
* Open socket.
*/
- {
- char addrbuf[100];
- sk_getaddr(addr, addrbuf, 100);
- logeventf(ssh, "Connecting to %s port %d", addrbuf, port);
- }
ssh->fn = &fn_table;
ssh->s = new_connection(addr, *realhost, port,
0, 1, nodelay, keepalive, (Plug) ssh, &ssh->cfg);
ssh->v1_throttle_count += adjust;
assert(ssh->v1_throttle_count >= 0);
if (ssh->v1_throttle_count && !old_count) {
- sk_set_frozen(ssh->s, 1);
+ ssh_set_frozen(ssh, 1);
} else if (!ssh->v1_throttle_count && old_count) {
- sk_set_frozen(ssh->s, 0);
+ ssh_set_frozen(ssh, 0);
}
}
}
}
-/*
- * Username and password input, abstracted off into routines
- * reusable in several places - even between SSH1 and SSH2.
- */
-
-/* Set up a username or password input loop on a given buffer. */
-static void setup_userpass_input(Ssh ssh, char *buffer, int buflen, int echo)
-{
- ssh->userpass_input_buffer = buffer;
- ssh->userpass_input_buflen = buflen;
- ssh->userpass_input_bufpos = 0;
- ssh->userpass_input_echo = echo;
-}
-
-/*
- * Process some terminal data in the course of username/password
- * input. Returns >0 for success (line of input returned in
- * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
- * for inconclusive (keep waiting for more input please).
- */
-static int process_userpass_input(Ssh ssh, unsigned char *in, int inlen)
-{
- char c;
-
- while (inlen--) {
- switch (c = *in++) {
- case 10:
- case 13:
- ssh->userpass_input_buffer[ssh->userpass_input_bufpos] = 0;
- ssh->userpass_input_buffer[ssh->userpass_input_buflen-1] = 0;
- return +1;
- break;
- case 8:
- case 127:
- if (ssh->userpass_input_bufpos > 0) {
- if (ssh->userpass_input_echo)
- c_write_str(ssh, "\b \b");
- ssh->userpass_input_bufpos--;
- }
- break;
- case 21:
- case 27:
- while (ssh->userpass_input_bufpos > 0) {
- if (ssh->userpass_input_echo)
- c_write_str(ssh, "\b \b");
- ssh->userpass_input_bufpos--;
- }
- break;
- case 3:
- case 4:
- return -1;
- break;
- default:
- /*
- * This simplistic check for printability is disabled
- * when we're doing password input, because some people
- * have control characters in their passwords.o
- */
- if ((!ssh->userpass_input_echo ||
- (c >= ' ' && c <= '~') ||
- ((unsigned char) c >= 160))
- && ssh->userpass_input_bufpos < ssh->userpass_input_buflen-1) {
- ssh->userpass_input_buffer[ssh->userpass_input_bufpos++] = c;
- if (ssh->userpass_input_echo)
- c_write(ssh, &c, 1);
- }
- break;
- }
- }
- return 0;
-}
-
static void ssh_agent_callback(void *sshv, void *reply, int replylen)
{
Ssh ssh = (Ssh) sshv;
do_ssh2_authconn(ssh, NULL, -1, NULL);
}
-static void ssh_agentf_callback(void *cv, void *reply, int replylen)
+static void ssh_dialog_callback(void *sshv, int ret)
+{
+ Ssh ssh = (Ssh) sshv;
+
+ ssh->user_response = ret;
+
+ if (ssh->version == 1)
+ do_ssh1_login(ssh, NULL, -1, NULL);
+ else
+ do_ssh2_transport(ssh, NULL, -1, NULL);
+
+ /*
+ * This may have unfrozen the SSH connection, so do a
+ * queued-data run.
+ */
+ ssh_process_queued_incoming_data(ssh);
+}
+
+static void ssh_agentf_callback(void *cv, void *reply, int replylen)
{
struct ssh_channel *c = (struct ssh_channel *)cv;
Ssh ssh = c->ssh;
}
/*
+ * Client-initiated disconnection. Send a DISCONNECT if `wire_reason'
+ * non-NULL, otherwise just close the connection. `client_reason' == NULL
+ * => log `wire_reason'.
+ */
+static void ssh_disconnect(Ssh ssh, char *client_reason, char *wire_reason,
+ int code, int clean_exit)
+{
+ char *error;
+ if (!client_reason)
+ client_reason = wire_reason;
+ if (client_reason)
+ error = dupprintf("Disconnected: %s", client_reason);
+ else
+ error = dupstr("Disconnected");
+ if (wire_reason) {
+ if (ssh->version == 1) {
+ send_packet(ssh, SSH1_MSG_DISCONNECT, PKT_STR, wire_reason,
+ PKT_END);
+ } else if (ssh->version == 2) {
+ struct Packet *pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
+ ssh2_pkt_adduint32(pktout, code);
+ ssh2_pkt_addstring(pktout, wire_reason);
+ ssh2_pkt_addstring(pktout, "en"); /* language tag */
+ ssh2_pkt_send_noqueue(ssh, pktout);
+ }
+ }
+ ssh->close_expected = TRUE;
+ ssh->clean_exit = clean_exit;
+ ssh_closing((Plug)ssh, error, 0, 0);
+ sfree(error);
+}
+
+/*
* Handle the key exchange and user authentication phases.
*/
static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
char username[100];
void *publickey_blob;
int publickey_bloblen;
- char password[100];
- char prompt[200];
- int pos;
+ char *publickey_comment;
+ int publickey_encrypted;
+ prompts_t *cur_prompt;
char c;
int pwpkt_type;
unsigned char request[5], *response, *p;
Bignum challenge;
char *commentp;
int commentlen;
+ int dlgret;
};
crState(do_ssh1_login_state);
ptr = ssh_pkt_getdata(pktin, 8);
if (!ptr) {
- bombout(("SSH1 public key packet stopped before random cookie"));
+ bombout(("SSH-1 public key packet stopped before random cookie"));
crStop(0);
}
memcpy(cookie, ptr, 8);
if (!ssh1_pkt_getrsakey(pktin, &servkey, &s->keystr1) ||
!ssh1_pkt_getrsakey(pktin, &hostkey, &s->keystr2)) {
- bombout(("Failed to read SSH1 public keys from public key packet"));
+ bombout(("Failed to read SSH-1 public keys from public key packet"));
crStop(0);
}
*/
if (hostkey.bits > hostkey.bytes * 8 ||
servkey.bits > servkey.bytes * 8) {
- bombout(("SSH1 public keys were badly formatted"));
+ bombout(("SSH-1 public keys were badly formatted"));
crStop(0);
}
s->len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
s->rsabuf = snewn(s->len, unsigned char);
- if (!s->rsabuf)
- fatalbox("Out of memory");
/*
* Verify the host key.
int len = rsastr_len(&hostkey);
char fingerprint[100];
char *keystr = snewn(len, char);
- if (!keystr)
- fatalbox("Out of memory");
rsastr_fmt(keystr, &hostkey);
rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
- verify_ssh_host_key(ssh->frontend,
- ssh->savedhost, ssh->savedport, "rsa", keystr,
- fingerprint);
+
+ ssh_set_frozen(ssh, 1);
+ s->dlgret = verify_ssh_host_key(ssh->frontend,
+ ssh->savedhost, ssh->savedport,
+ "rsa", keystr, fingerprint,
+ ssh_dialog_callback, ssh);
sfree(keystr);
+ if (s->dlgret < 0) {
+ do {
+ crReturn(0);
+ if (pktin) {
+ bombout(("Unexpected data from server while waiting"
+ " for user host key response"));
+ crStop(0);
+ }
+ } while (pktin || inlen > 0);
+ s->dlgret = ssh->user_response;
+ }
+ ssh_set_frozen(ssh, 0);
+
+ if (s->dlgret == 0) {
+ ssh_disconnect(ssh, "User aborted at host key verification",
+ NULL, 0, TRUE);
+ crStop(0);
+ }
}
for (i = 0; i < 32; i++) {
ret = rsaencrypt(s->rsabuf, hostkey.bytes, &servkey);
}
if (!ret) {
- bombout(("SSH1 public key encryptions failed due to bad formatting"));
+ bombout(("SSH-1 public key encryptions failed due to bad formatting"));
crStop(0);
}
warn = 1;
} else if (next_cipher == CIPHER_AES) {
/* XXX Probably don't need to mention this. */
- logevent("AES not supported in SSH1, skipping");
+ logevent("AES not supported in SSH-1, skipping");
} else {
switch (next_cipher) {
case CIPHER_3DES: s->cipher_type = SSH_CIPHER_3DES;
}
if (!cipher_chosen) {
if ((s->supported_ciphers_mask & (1 << SSH_CIPHER_3DES)) == 0)
- bombout(("Server violates SSH 1 protocol by not "
+ bombout(("Server violates SSH-1 protocol by not "
"supporting 3DES encryption"));
else
/* shouldn't happen */
}
/* Warn about chosen cipher if necessary. */
- if (warn)
- askcipher(ssh->frontend, cipher_string, 0);
+ if (warn) {
+ ssh_set_frozen(ssh, 1);
+ s->dlgret = askalg(ssh->frontend, "cipher", cipher_string,
+ ssh_dialog_callback, ssh);
+ if (s->dlgret < 0) {
+ do {
+ crReturn(0);
+ if (pktin) {
+ bombout(("Unexpected data from server while waiting"
+ " for user response"));
+ crStop(0);
+ }
+ } while (pktin || inlen > 0);
+ s->dlgret = ssh->user_response;
+ }
+ ssh_set_frozen(ssh, 0);
+ if (s->dlgret == 0) {
+ ssh_disconnect(ssh, "User aborted at cipher warning", NULL,
+ 0, TRUE);
+ crStop(0);
+ }
+ }
}
switch (s->cipher_type) {
logevent("Successfully started encryption");
- fflush(stdout);
+ fflush(stdout); /* FIXME eh? */
{
if (!*ssh->cfg.username) {
- if (ssh_get_line && !ssh_getline_pw_only) {
- if (!ssh_get_line("login as: ",
- s->username, sizeof(s->username), FALSE)) {
- /*
- * get_line failed to get a username.
- * Terminate.
- */
- logevent("No username provided. Abandoning session.");
- ssh_closing((Plug)ssh, NULL, 0, 0);
- crStop(1);
- }
- } else {
- int ret; /* need not be kept over crReturn */
- c_write_str(ssh, "login as: ");
+ int ret; /* need not be kept over crReturn */
+ s->cur_prompt = new_prompts(ssh->frontend);
+ s->cur_prompt->to_server = TRUE;
+ s->cur_prompt->name = dupstr("SSH login name");
+ add_prompt(s->cur_prompt, dupstr("login as: "), TRUE,
+ lenof(s->username));
+ ret = get_userpass_input(s->cur_prompt, NULL, 0);
+ while (ret < 0) {
ssh->send_ok = 1;
-
- setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
- do {
- crWaitUntil(!pktin);
- ret = process_userpass_input(ssh, in, inlen);
- } while (ret == 0);
- if (ret < 0)
- cleanup_exit(0);
- c_write_str(ssh, "\r\n");
+ crWaitUntil(!pktin);
+ ret = get_userpass_input(s->cur_prompt, in, inlen);
+ ssh->send_ok = 0;
+ }
+ if (!ret) {
+ /*
+ * Failed to get a username. Terminate.
+ */
+ free_prompts(s->cur_prompt);
+ ssh_disconnect(ssh, "No username provided", NULL, 0, TRUE);
+ crStop(0);
}
+ memcpy(s->username, s->cur_prompt->prompts[0]->result,
+ lenof(s->username));
+ free_prompts(s->cur_prompt);
} else {
strncpy(s->username, ssh->cfg.username, sizeof(s->username));
s->username[sizeof(s->username)-1] = '\0';
send_packet(ssh, SSH1_CMSG_USER, PKT_STR, s->username, PKT_END);
{
- char userlog[22 + sizeof(s->username)];
- sprintf(userlog, "Sent username \"%s\"", s->username);
+ char *userlog = dupprintf("Sent username \"%s\"", s->username);
logevent(userlog);
if (flags & FLAG_INTERACTIVE &&
(!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
- strcat(userlog, "\r\n");
c_write_str(ssh, userlog);
+ c_write_str(ssh, "\r\n");
}
+ sfree(userlog);
}
}
s->tried_publickey = s->tried_agent = 0;
}
s->tis_auth_refused = s->ccard_auth_refused = 0;
- /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
+ /*
+ * Load the public half of any configured keyfile for later use.
+ */
if (!filename_is_null(ssh->cfg.keyfile)) {
- if (!rsakey_pubblob(&ssh->cfg.keyfile,
- &s->publickey_blob, &s->publickey_bloblen, NULL))
+ int keytype;
+ logeventf(ssh, "Reading private key file \"%.150s\"",
+ filename_to_str(&ssh->cfg.keyfile));
+ keytype = key_type(&ssh->cfg.keyfile);
+ if (keytype == SSH_KEYTYPE_SSH1) {
+ const char *error;
+ if (rsakey_pubblob(&ssh->cfg.keyfile,
+ &s->publickey_blob, &s->publickey_bloblen,
+ &s->publickey_comment, &error)) {
+ s->publickey_encrypted = rsakey_encrypted(&ssh->cfg.keyfile,
+ NULL);
+ } else {
+ char *msgbuf;
+ logeventf(ssh, "Unable to load private key (%s)", error);
+ msgbuf = dupprintf("Unable to load private key file "
+ "\"%.150s\" (%s)\r\n",
+ filename_to_str(&ssh->cfg.keyfile),
+ error);
+ c_write_str(ssh, msgbuf);
+ sfree(msgbuf);
+ s->publickey_blob = NULL;
+ }
+ } else {
+ char *msgbuf;
+ logeventf(ssh, "Unable to use this key file (%s)",
+ key_type_to_str(keytype));
+ msgbuf = dupprintf("Unable to use key file \"%.150s\""
+ " (%s)\r\n",
+ filename_to_str(&ssh->cfg.keyfile),
+ key_type_to_str(keytype));
+ c_write_str(ssh, msgbuf);
+ sfree(msgbuf);
s->publickey_blob = NULL;
+ }
} else
s->publickey_blob = NULL;
s->p = s->response + 5;
s->nkeys = GET_32BIT(s->p);
s->p += 4;
- {
- char buf[64];
- sprintf(buf, "Pageant has %d SSH1 keys", s->nkeys);
- logevent(buf);
- }
+ logeventf(ssh, "Pageant has %d SSH-1 keys", s->nkeys);
for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
- {
- char buf[64];
- sprintf(buf, "Trying Pageant key #%d", s->keyi);
- logevent(buf);
- }
+ logeventf(ssh, "Trying Pageant key #%d", s->keyi);
if (s->publickey_blob &&
!memcmp(s->p, s->publickey_blob,
s->publickey_bloblen)) {
if (s->authed)
break;
}
- if (!filename_is_null(ssh->cfg.keyfile) && !s->tried_publickey)
- s->pwpkt_type = SSH1_CMSG_AUTH_RSA;
+ if (s->publickey_blob && !s->tried_publickey) {
+ /*
+ * Try public key authentication with the specified
+ * key file.
+ */
+ int got_passphrase; /* need not be kept over crReturn */
+ if (flags & FLAG_VERBOSE)
+ c_write_str(ssh, "Trying public key authentication.\r\n");
+ logeventf(ssh, "Trying public key \"%s\"",
+ filename_to_str(&ssh->cfg.keyfile));
+ s->tried_publickey = 1;
+ got_passphrase = FALSE;
+ while (!got_passphrase) {
+ /*
+ * Get a passphrase, if necessary.
+ */
+ char *passphrase = NULL; /* only written after crReturn */
+ const char *error;
+ if (!s->publickey_encrypted) {
+ if (flags & FLAG_VERBOSE)
+ c_write_str(ssh, "No passphrase required.\r\n");
+ passphrase = NULL;
+ } else {
+ int ret; /* need not be kept over crReturn */
+ s->cur_prompt = new_prompts(ssh->frontend);
+ s->cur_prompt->to_server = FALSE;
+ s->cur_prompt->name = dupstr("SSH key passphrase");
+ add_prompt(s->cur_prompt,
+ dupprintf("Passphrase for key \"%.100s\": ",
+ s->publickey_comment),
+ FALSE, SSH_MAX_PASSWORD_LEN);
+ ret = get_userpass_input(s->cur_prompt, NULL, 0);
+ while (ret < 0) {
+ ssh->send_ok = 1;
+ crWaitUntil(!pktin);
+ ret = get_userpass_input(s->cur_prompt, in, inlen);
+ ssh->send_ok = 0;
+ }
+ if (!ret) {
+ /* Failed to get a passphrase. Terminate. */
+ free_prompts(s->cur_prompt);
+ ssh_disconnect(ssh, NULL, "Unable to authenticate",
+ 0, TRUE);
+ crStop(0);
+ }
+ passphrase = dupstr(s->cur_prompt->prompts[0]->result);
+ free_prompts(s->cur_prompt);
+ }
+ /*
+ * Try decrypting key with passphrase.
+ */
+ ret = loadrsakey(&ssh->cfg.keyfile, &s->key, passphrase,
+ &error);
+ if (passphrase) {
+ memset(passphrase, 0, strlen(passphrase));
+ sfree(passphrase);
+ }
+ if (ret == 1) {
+ /* Correct passphrase. */
+ got_passphrase = TRUE;
+ } else if (ret == 0) {
+ c_write_str(ssh, "Couldn't load private key from ");
+ c_write_str(ssh, filename_to_str(&ssh->cfg.keyfile));
+ c_write_str(ssh, " (");
+ c_write_str(ssh, error);
+ c_write_str(ssh, ").\r\n");
+ got_passphrase = FALSE;
+ break; /* go and try something else */
+ } else if (ret == -1) {
+ c_write_str(ssh, "Wrong passphrase.\r\n"); /* FIXME */
+ s->tried_publickey = 0;
+ got_passphrase = FALSE;
+ /* and try again */
+ }
+ }
+
+ if (got_passphrase) {
+
+ /*
+ * Send a public key attempt.
+ */
+ send_packet(ssh, SSH1_CMSG_AUTH_RSA,
+ PKT_BIGNUM, s->key.modulus, PKT_END);
+
+ crWaitUntil(pktin);
+ if (pktin->type == SSH1_SMSG_FAILURE) {
+ c_write_str(ssh, "Server refused our public key.\r\n");
+ continue; /* go and try password */
+ }
+ if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
+ bombout(("Bizarre response to offer of public key"));
+ crStop(0);
+ }
+
+ {
+ int i;
+ unsigned char buffer[32];
+ Bignum challenge, response;
+
+ if ((challenge = ssh1_pkt_getmp(pktin)) == NULL) {
+ bombout(("Server's RSA challenge was badly formatted"));
+ crStop(0);
+ }
+ response = rsadecrypt(challenge, &s->key);
+ freebn(s->key.private_exponent);/* burn the evidence */
+
+ for (i = 0; i < 32; i++) {
+ buffer[i] = bignum_byte(response, 31 - i);
+ }
+
+ MD5Init(&md5c);
+ MD5Update(&md5c, buffer, 32);
+ MD5Update(&md5c, s->session_id, 16);
+ MD5Final(buffer, &md5c);
+
+ send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
+ PKT_DATA, buffer, 16, PKT_END);
+
+ freebn(challenge);
+ freebn(response);
+ }
+
+ crWaitUntil(pktin);
+ if (pktin->type == SSH1_SMSG_FAILURE) {
+ if (flags & FLAG_VERBOSE)
+ c_write_str(ssh, "Failed to authenticate with"
+ " our public key.\r\n");
+ continue; /* go and try password */
+ } else if (pktin->type != SSH1_SMSG_SUCCESS) {
+ bombout(("Bizarre response to RSA authentication response"));
+ crStop(0);
+ }
+
+ break; /* we're through! */
+ }
+
+ }
+
+ /*
+ * Otherwise, try various forms of password-like authentication.
+ */
+ s->cur_prompt = new_prompts(ssh->frontend);
if (ssh->cfg.try_tis_auth &&
(s->supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
} else {
char *challenge;
int challengelen;
+ char *instr_suf, *prompt;
ssh_pkt_getstring(pktin, &challenge, &challengelen);
if (!challenge) {
crStop(0);
}
logevent("Received TIS challenge");
- if (challengelen > sizeof(s->prompt) - 1)
- challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
- memcpy(s->prompt, challenge, challengelen);
+ s->cur_prompt->to_server = TRUE;
+ s->cur_prompt->name = dupstr("SSH TIS authentication");
/* Prompt heuristic comes from OpenSSH */
- strncpy(s->prompt + challengelen,
- memchr(s->prompt, '\n', challengelen) ?
- "": "\r\nResponse: ",
- (sizeof s->prompt) - challengelen);
- s->prompt[(sizeof s->prompt) - 1] = '\0';
+ if (memchr(challenge, '\n', challengelen)) {
+ instr_suf = dupstr("");
+ prompt = dupprintf("%.*s", challengelen, challenge);
+ } else {
+ instr_suf = dupprintf("%.*s", challengelen, challenge);
+ prompt = dupstr("Response: ");
+ }
+ s->cur_prompt->instruction =
+ dupprintf("Using TIS authentication.%s%s",
+ (*instr_suf) ? "\n" : "",
+ instr_suf);
+ s->cur_prompt->instr_reqd = TRUE;
+ add_prompt(s->cur_prompt, prompt, FALSE, SSH_MAX_PASSWORD_LEN);
+ sfree(instr_suf);
}
}
if (ssh->cfg.try_tis_auth &&
} else {
char *challenge;
int challengelen;
+ char *instr_suf, *prompt;
ssh_pkt_getstring(pktin, &challenge, &challengelen);
if (!challenge) {
crStop(0);
}
logevent("Received CryptoCard challenge");
- if (challengelen > sizeof(s->prompt) - 1)
- challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
- memcpy(s->prompt, challenge, challengelen);
- strncpy(s->prompt + challengelen,
- memchr(s->prompt, '\n', challengelen) ?
- "" : "\r\nResponse: ",
- sizeof(s->prompt) - challengelen);
- s->prompt[sizeof(s->prompt) - 1] = '\0';
+ s->cur_prompt->to_server = TRUE;
+ s->cur_prompt->name = dupstr("SSH CryptoCard authentication");
+ s->cur_prompt->name_reqd = FALSE;
+ /* Prompt heuristic comes from OpenSSH */
+ if (memchr(challenge, '\n', challengelen)) {
+ instr_suf = dupstr("");
+ prompt = dupprintf("%.*s", challengelen, challenge);
+ } else {
+ instr_suf = dupprintf("%.*s", challengelen, challenge);
+ prompt = dupstr("Response: ");
+ }
+ s->cur_prompt->instruction =
+ dupprintf("Using CryptoCard authentication.%s%s",
+ (*instr_suf) ? "\n" : "",
+ instr_suf);
+ s->cur_prompt->instr_reqd = TRUE;
+ add_prompt(s->cur_prompt, prompt, FALSE, SSH_MAX_PASSWORD_LEN);
+ sfree(instr_suf);
}
}
if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
- sprintf(s->prompt, "%.90s@%.90s's password: ",
- s->username, ssh->savedhost);
- }
- if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
- char *comment = NULL;
- int type;
- char msgbuf[256];
- if (flags & FLAG_VERBOSE)
- c_write_str(ssh, "Trying public key authentication.\r\n");
- logeventf(ssh, "Trying public key \"%s\"",
- filename_to_str(&ssh->cfg.keyfile));
- type = key_type(&ssh->cfg.keyfile);
- if (type != SSH_KEYTYPE_SSH1) {
- sprintf(msgbuf, "Key is of wrong type (%s)",
- key_type_to_str(type));
- logevent(msgbuf);
- c_write_str(ssh, msgbuf);
- c_write_str(ssh, "\r\n");
- s->tried_publickey = 1;
- continue;
- }
- if (!rsakey_encrypted(&ssh->cfg.keyfile, &comment)) {
- if (flags & FLAG_VERBOSE)
- c_write_str(ssh, "No passphrase required.\r\n");
- goto tryauth;
- }
- sprintf(s->prompt, "Passphrase for key \"%.100s\": ", comment);
- sfree(comment);
+ s->cur_prompt->to_server = TRUE;
+ s->cur_prompt->name = dupstr("SSH password");
+ add_prompt(s->cur_prompt, dupprintf("%.90s@%.90s's password: ",
+ s->username, ssh->savedhost),
+ FALSE, SSH_MAX_PASSWORD_LEN);
}
/*
* or CryptoCard exchange if we're doing TIS or CryptoCard
* authentication.
*/
- if (ssh_get_line) {
- if (!ssh_get_line(s->prompt, s->password,
- sizeof(s->password), TRUE)) {
+ {
+ int ret; /* need not be kept over crReturn */
+ ret = get_userpass_input(s->cur_prompt, NULL, 0);
+ while (ret < 0) {
+ ssh->send_ok = 1;
+ crWaitUntil(!pktin);
+ ret = get_userpass_input(s->cur_prompt, in, inlen);
+ ssh->send_ok = 0;
+ }
+ if (!ret) {
/*
- * get_line failed to get a password (for example
+ * Failed to get a password (for example
* because one was supplied on the command line
* which has already failed to work). Terminate.
*/
- send_packet(ssh, SSH1_MSG_DISCONNECT,
- PKT_STR, "No more passwords available to try",
- PKT_END);
- logevent("Unable to authenticate");
- connection_fatal(ssh->frontend, "Unable to authenticate");
- ssh_closing((Plug)ssh, NULL, 0, 0);
- crStop(1);
+ free_prompts(s->cur_prompt);
+ ssh_disconnect(ssh, NULL, "Unable to authenticate", 0, TRUE);
+ crStop(0);
}
- } else {
- /* Prompt may have come from server. We've munged it a bit, so
- * we know it to be zero-terminated at least once. */
- int ret; /* need not be saved over crReturn */
- c_write_untrusted(ssh, s->prompt, strlen(s->prompt));
- s->pos = 0;
-
- setup_userpass_input(ssh, s->password, sizeof(s->password), 0);
- do {
- crWaitUntil(!pktin);
- ret = process_userpass_input(ssh, in, inlen);
- } while (ret == 0);
- if (ret < 0)
- cleanup_exit(0);
- c_write_str(ssh, "\r\n");
}
- tryauth:
- if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
- /*
- * Try public key authentication with the specified
- * key file.
- */
- s->tried_publickey = 1;
-
- {
- const char *error = NULL;
- int ret = loadrsakey(&ssh->cfg.keyfile, &s->key, s->password,
- &error);
- if (ret == 0) {
- c_write_str(ssh, "Couldn't load private key from ");
- c_write_str(ssh, filename_to_str(&ssh->cfg.keyfile));
- c_write_str(ssh, " (");
- c_write_str(ssh, error);
- c_write_str(ssh, ").\r\n");
- continue; /* go and try password */
- }
- if (ret == -1) {
- c_write_str(ssh, "Wrong passphrase.\r\n");
- s->tried_publickey = 0;
- continue; /* try again */
- }
- }
-
+ if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
/*
- * Send a public key attempt.
+ * Defence against traffic analysis: we send a
+ * whole bunch of packets containing strings of
+ * different lengths. One of these strings is the
+ * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
+ * The others are all random data in
+ * SSH1_MSG_IGNORE packets. This way a passive
+ * listener can't tell which is the password, and
+ * hence can't deduce the password length.
+ *
+ * Anybody with a password length greater than 16
+ * bytes is going to have enough entropy in their
+ * password that a listener won't find it _that_
+ * much help to know how long it is. So what we'll
+ * do is:
+ *
+ * - if password length < 16, we send 15 packets
+ * containing string lengths 1 through 15
+ *
+ * - otherwise, we let N be the nearest multiple
+ * of 8 below the password length, and send 8
+ * packets containing string lengths N through
+ * N+7. This won't obscure the order of
+ * magnitude of the password length, but it will
+ * introduce a bit of extra uncertainty.
+ *
+ * A few servers (the old 1.2.18 through 1.2.22)
+ * can't deal with SSH1_MSG_IGNORE. For these
+ * servers, we need an alternative defence. We make
+ * use of the fact that the password is interpreted
+ * as a C string: so we can append a NUL, then some
+ * random data.
+ *
+ * One server (a Cisco one) can deal with neither
+ * SSH1_MSG_IGNORE _nor_ a padded password string.
+ * For this server we are left with no defences
+ * against password length sniffing.
*/
- send_packet(ssh, SSH1_CMSG_AUTH_RSA,
- PKT_BIGNUM, s->key.modulus, PKT_END);
-
- crWaitUntil(pktin);
- if (pktin->type == SSH1_SMSG_FAILURE) {
- c_write_str(ssh, "Server refused our public key.\r\n");
- continue; /* go and try password */
- }
- if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
- bombout(("Bizarre response to offer of public key"));
- crStop(0);
- }
-
- {
- int i;
- unsigned char buffer[32];
- Bignum challenge, response;
-
- if ((challenge = ssh1_pkt_getmp(pktin)) == NULL) {
- bombout(("Server's RSA challenge was badly formatted"));
- crStop(0);
- }
- response = rsadecrypt(challenge, &s->key);
- freebn(s->key.private_exponent);/* burn the evidence */
-
- for (i = 0; i < 32; i++) {
- buffer[i] = bignum_byte(response, 31 - i);
- }
-
- MD5Init(&md5c);
- MD5Update(&md5c, buffer, 32);
- MD5Update(&md5c, s->session_id, 16);
- MD5Final(buffer, &md5c);
-
- send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
- PKT_DATA, buffer, 16, PKT_END);
-
- freebn(challenge);
- freebn(response);
- }
-
- crWaitUntil(pktin);
- if (pktin->type == SSH1_SMSG_FAILURE) {
- if (flags & FLAG_VERBOSE)
- c_write_str(ssh, "Failed to authenticate with"
- " our public key.\r\n");
- continue; /* go and try password */
- } else if (pktin->type != SSH1_SMSG_SUCCESS) {
- bombout(("Bizarre response to RSA authentication response"));
- crStop(0);
- }
-
- break; /* we're through! */
- } else {
- if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
+ if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
/*
- * Defence against traffic analysis: we send a
- * whole bunch of packets containing strings of
- * different lengths. One of these strings is the
- * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
- * The others are all random data in
- * SSH1_MSG_IGNORE packets. This way a passive
- * listener can't tell which is the password, and
- * hence can't deduce the password length.
- *
- * Anybody with a password length greater than 16
- * bytes is going to have enough entropy in their
- * password that a listener won't find it _that_
- * much help to know how long it is. So what we'll
- * do is:
- *
- * - if password length < 16, we send 15 packets
- * containing string lengths 1 through 15
- *
- * - otherwise, we let N be the nearest multiple
- * of 8 below the password length, and send 8
- * packets containing string lengths N through
- * N+7. This won't obscure the order of
- * magnitude of the password length, but it will
- * introduce a bit of extra uncertainty.
- *
- * A few servers (the old 1.2.18 through 1.2.22)
- * can't deal with SSH1_MSG_IGNORE. For these
- * servers, we need an alternative defence. We make
- * use of the fact that the password is interpreted
- * as a C string: so we can append a NUL, then some
- * random data.
- *
- * One server (a Cisco one) can deal with neither
- * SSH1_MSG_IGNORE _nor_ a padded password string.
- * For this server we are left with no defences
- * against password length sniffing.
+ * The server can deal with SSH1_MSG_IGNORE, so
+ * we can use the primary defence.
*/
- if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
- /*
- * The server can deal with SSH1_MSG_IGNORE, so
- * we can use the primary defence.
- */
- int bottom, top, pwlen, i;
- char *randomstr;
+ int bottom, top, pwlen, i;
+ char *randomstr;
- pwlen = strlen(s->password);
- if (pwlen < 16) {
- bottom = 0; /* zero length passwords are OK! :-) */
- top = 15;
- } else {
- bottom = pwlen & ~7;
- top = bottom + 7;
- }
+ pwlen = strlen(s->cur_prompt->prompts[0]->result);
+ if (pwlen < 16) {
+ bottom = 0; /* zero length passwords are OK! :-) */
+ top = 15;
+ } else {
+ bottom = pwlen & ~7;
+ top = bottom + 7;
+ }
- assert(pwlen >= bottom && pwlen <= top);
+ assert(pwlen >= bottom && pwlen <= top);
- randomstr = snewn(top + 1, char);
+ randomstr = snewn(top + 1, char);
- for (i = bottom; i <= top; i++) {
- if (i == pwlen) {
- defer_packet(ssh, s->pwpkt_type,
- PKTT_PASSWORD, PKT_STR, s->password,
- PKTT_OTHER, PKT_END);
- } else {
- for (j = 0; j < i; j++) {
- do {
- randomstr[j] = random_byte();
- } while (randomstr[j] == '\0');
- }
- randomstr[i] = '\0';
- defer_packet(ssh, SSH1_MSG_IGNORE,
- PKT_STR, randomstr, PKT_END);
+ for (i = bottom; i <= top; i++) {
+ if (i == pwlen) {
+ defer_packet(ssh, s->pwpkt_type,
+ PKTT_PASSWORD, PKT_STR,
+ s->cur_prompt->prompts[0]->result,
+ PKTT_OTHER, PKT_END);
+ } else {
+ for (j = 0; j < i; j++) {
+ do {
+ randomstr[j] = random_byte();
+ } while (randomstr[j] == '\0');
}
+ randomstr[i] = '\0';
+ defer_packet(ssh, SSH1_MSG_IGNORE,
+ PKT_STR, randomstr, PKT_END);
}
- logevent("Sending password with camouflage packets");
- ssh_pkt_defersend(ssh);
- sfree(randomstr);
- }
- else if (!(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
- /*
- * The server can't deal with SSH1_MSG_IGNORE
- * but can deal with padded passwords, so we
- * can use the secondary defence.
- */
- char string[64];
- char *ss;
- int len;
-
- len = strlen(s->password);
- if (len < sizeof(string)) {
- ss = string;
- strcpy(string, s->password);
- len++; /* cover the zero byte */
- while (len < sizeof(string)) {
- string[len++] = (char) random_byte();
- }
- } else {
- ss = s->password;
+ }
+ logevent("Sending password with camouflage packets");
+ ssh_pkt_defersend(ssh);
+ sfree(randomstr);
+ }
+ else if (!(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
+ /*
+ * The server can't deal with SSH1_MSG_IGNORE
+ * but can deal with padded passwords, so we
+ * can use the secondary defence.
+ */
+ char string[64];
+ char *ss;
+ int len;
+
+ len = strlen(s->cur_prompt->prompts[0]->result);
+ if (len < sizeof(string)) {
+ ss = string;
+ strcpy(string, s->cur_prompt->prompts[0]->result);
+ len++; /* cover the zero byte */
+ while (len < sizeof(string)) {
+ string[len++] = (char) random_byte();
}
- logevent("Sending length-padded password");
- send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
- PKT_INT, len, PKT_DATA, ss, len,
- PKTT_OTHER, PKT_END);
} else {
- /*
- * The server has _both_
- * BUG_CHOKES_ON_SSH1_IGNORE and
- * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
- * therefore nothing we can do.
- */
- int len;
- len = strlen(s->password);
- logevent("Sending unpadded password");
- send_packet(ssh, s->pwpkt_type,
- PKTT_PASSWORD, PKT_INT, len,
- PKT_DATA, s->password, len,
- PKTT_OTHER, PKT_END);
+ ss = s->cur_prompt->prompts[0]->result;
}
- } else {
+ logevent("Sending length-padded password");
send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
- PKT_STR, s->password, PKTT_OTHER, PKT_END);
+ PKT_INT, len, PKT_DATA, ss, len,
+ PKTT_OTHER, PKT_END);
+ } else {
+ /*
+ * The server has _both_
+ * BUG_CHOKES_ON_SSH1_IGNORE and
+ * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
+ * therefore nothing we can do.
+ */
+ int len;
+ len = strlen(s->cur_prompt->prompts[0]->result);
+ logevent("Sending unpadded password");
+ send_packet(ssh, s->pwpkt_type,
+ PKTT_PASSWORD, PKT_INT, len,
+ PKT_DATA, s->cur_prompt->prompts[0]->result, len,
+ PKTT_OTHER, PKT_END);
}
+ } else {
+ send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
+ PKT_STR, s->cur_prompt->prompts[0]->result,
+ PKTT_OTHER, PKT_END);
}
logevent("Sent password");
- memset(s->password, 0, strlen(s->password));
+ free_prompts(s->cur_prompt);
crWaitUntil(pktin);
if (pktin->type == SSH1_SMSG_FAILURE) {
if (flags & FLAG_VERBOSE)
}
}
+ /* Clear up */
+ if (s->publickey_blob) {
+ sfree(s->publickey_blob);
+ sfree(s->publickey_comment);
+ }
+
logevent("Authentication successful");
crFinish(1);
{
Ssh ssh = c->ssh;
- if (ssh->state != SSH_STATE_SESSION) {
- assert(ssh->state == SSH_STATE_CLOSED);
+ if (ssh->state == SSH_STATE_CLOSED)
return;
- }
if (c && !c->closes) {
/*
- * If the channel's remoteid is -1, we have sent
+ * If halfopen is true, we have sent
* CHANNEL_OPEN for this channel, but it hasn't even been
* acknowledged by the server. So we must set a close flag
* on it now, and then when the server acks the channel
* open, we can close it then.
*/
- if (((int)c->remoteid) != -1) {
+ if (!c->halfopen) {
if (ssh->version == 1) {
send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
PKT_END);
{
Ssh ssh = c->ssh;
- if (ssh->state != SSH_STATE_SESSION) {
- assert(ssh->state == SSH_STATE_CLOSED);
+ if (ssh->state == SSH_STATE_CLOSED)
return 0;
- }
if (ssh->version == 1) {
send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
PKT_INT, len, PKT_DATA, buf, len,
PKTT_OTHER, PKT_END);
/*
- * In SSH1 we can return 0 here - implying that forwarded
+ * In SSH-1 we can return 0 here - implying that forwarded
* connections are never individually throttled - because
* the only circumstance that can cause throttling will be
* the whole SSH connection backing up, in which case
{
Ssh ssh = c->ssh;
- if (ssh->state != SSH_STATE_SESSION) {
- assert(ssh->state == SSH_STATE_CLOSED);
+ if (ssh->state == SSH_STATE_CLOSED)
return;
- }
if (ssh->version == 1) {
if (c->v.v1.throttling && bufsize < SSH1_BUFFER_LIMIT) {
}
}
+static void ssh_queueing_handler(Ssh ssh, struct Packet *pktin)
+{
+ struct queued_handler *qh = ssh->qhead;
+
+ assert(qh != NULL);
+
+ assert(pktin->type == qh->msg1 || pktin->type == qh->msg2);
+
+ if (qh->msg1 > 0) {
+ assert(ssh->packet_dispatch[qh->msg1] == ssh_queueing_handler);
+ ssh->packet_dispatch[qh->msg1] = NULL;
+ }
+ if (qh->msg2 > 0) {
+ assert(ssh->packet_dispatch[qh->msg2] == ssh_queueing_handler);
+ ssh->packet_dispatch[qh->msg2] = NULL;
+ }
+
+ if (qh->next) {
+ ssh->qhead = qh->next;
+
+ if (ssh->qhead->msg1 > 0) {
+ assert(ssh->packet_dispatch[ssh->qhead->msg1] == NULL);
+ ssh->packet_dispatch[ssh->qhead->msg1] = ssh_queueing_handler;
+ }
+ if (ssh->qhead->msg2 > 0) {
+ assert(ssh->packet_dispatch[ssh->qhead->msg2] == NULL);
+ ssh->packet_dispatch[ssh->qhead->msg2] = ssh_queueing_handler;
+ }
+ } else {
+ ssh->qhead = ssh->qtail = NULL;
+ ssh->packet_dispatch[pktin->type] = NULL;
+ }
+
+ qh->handler(ssh, pktin, qh->ctx);
+
+ sfree(qh);
+}
+
+static void ssh_queue_handler(Ssh ssh, int msg1, int msg2,
+ chandler_fn_t handler, void *ctx)
+{
+ struct queued_handler *qh;
+
+ qh = snew(struct queued_handler);
+ qh->msg1 = msg1;
+ qh->msg2 = msg2;
+ qh->handler = handler;
+ qh->ctx = ctx;
+ qh->next = NULL;
+
+ if (ssh->qtail == NULL) {
+ ssh->qhead = qh;
+
+ if (qh->msg1 > 0) {
+ assert(ssh->packet_dispatch[qh->msg1] == NULL);
+ ssh->packet_dispatch[qh->msg1] = ssh_queueing_handler;
+ }
+ if (qh->msg2 > 0) {
+ assert(ssh->packet_dispatch[qh->msg2] == NULL);
+ ssh->packet_dispatch[qh->msg2] = ssh_queueing_handler;
+ }
+ } else {
+ ssh->qtail->next = qh;
+ }
+ ssh->qtail = qh;
+}
+
+static void ssh_rportfwd_succfail(Ssh ssh, struct Packet *pktin, void *ctx)
+{
+ struct ssh_rportfwd *rpf, *pf = (struct ssh_rportfwd *)ctx;
+
+ if (pktin->type == (ssh->version == 1 ? SSH1_SMSG_SUCCESS :
+ SSH2_MSG_REQUEST_SUCCESS)) {
+ logeventf(ssh, "Remote port forwarding from %s enabled",
+ pf->sportdesc);
+ } else {
+ logeventf(ssh, "Remote port forwarding from %s refused",
+ pf->sportdesc);
+
+ rpf = del234(ssh->rportfwds, pf);
+ assert(rpf == pf);
+ free_rportfwd(pf);
+ }
+}
+
+static void ssh_setup_portfwd(Ssh ssh, const Config *cfg)
+{
+ const char *portfwd_strptr = cfg->portfwd;
+ struct ssh_portfwd *epf;
+ int i;
+
+ if (!ssh->portfwds) {
+ ssh->portfwds = newtree234(ssh_portcmp);
+ } else {
+ /*
+ * Go through the existing port forwardings and tag them
+ * with status==DESTROY. Any that we want to keep will be
+ * re-enabled (status==KEEP) as we go through the
+ * configuration and find out which bits are the same as
+ * they were before.
+ */
+ struct ssh_portfwd *epf;
+ int i;
+ for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
+ epf->status = DESTROY;
+ }
+
+ while (*portfwd_strptr) {
+ char address_family, type;
+ int sport,dport,sserv,dserv;
+ char sports[256], dports[256], saddr[256], host[256];
+ int n;
+
+ address_family = 'A';
+ type = 'L';
+ if (*portfwd_strptr == 'A' ||
+ *portfwd_strptr == '4' ||
+ *portfwd_strptr == '6')
+ address_family = *portfwd_strptr++;
+ if (*portfwd_strptr == 'L' ||
+ *portfwd_strptr == 'R' ||
+ *portfwd_strptr == 'D')
+ type = *portfwd_strptr++;
+
+ saddr[0] = '\0';
+
+ n = 0;
+ while (*portfwd_strptr && *portfwd_strptr != '\t') {
+ if (*portfwd_strptr == ':') {
+ /*
+ * We've seen a colon in the middle of the
+ * source port number. This means that
+ * everything we've seen until now is the
+ * source _address_, so we'll move it into
+ * saddr and start sports from the beginning
+ * again.
+ */
+ portfwd_strptr++;
+ sports[n] = '\0';
+ if (ssh->version == 1 && type == 'R') {
+ logeventf(ssh, "SSH-1 cannot handle remote source address "
+ "spec \"%s\"; ignoring", sports);
+ } else
+ strcpy(saddr, sports);
+ n = 0;
+ }
+ if (n < lenof(sports)-1) sports[n++] = *portfwd_strptr++;
+ }
+ sports[n] = 0;
+ if (type != 'D') {
+ if (*portfwd_strptr == '\t')
+ portfwd_strptr++;
+ n = 0;
+ while (*portfwd_strptr && *portfwd_strptr != ':') {
+ if (n < lenof(host)-1) host[n++] = *portfwd_strptr++;
+ }
+ host[n] = 0;
+ if (*portfwd_strptr == ':')
+ portfwd_strptr++;
+ n = 0;
+ while (*portfwd_strptr) {
+ if (n < lenof(dports)-1) dports[n++] = *portfwd_strptr++;
+ }
+ dports[n] = 0;
+ portfwd_strptr++;
+ dport = atoi(dports);
+ dserv = 0;
+ if (dport == 0) {
+ dserv = 1;
+ dport = net_service_lookup(dports);
+ if (!dport) {
+ logeventf(ssh, "Service lookup failed for destination"
+ " port \"%s\"", dports);
+ }
+ }
+ } else {
+ while (*portfwd_strptr) portfwd_strptr++;
+ host[0] = 0;
+ dports[0] = 0;
+ dport = dserv = -1;
+ portfwd_strptr++; /* eat the NUL and move to next one */
+ }
+ sport = atoi(sports);
+ sserv = 0;
+ if (sport == 0) {
+ sserv = 1;
+ sport = net_service_lookup(sports);
+ if (!sport) {
+ logeventf(ssh, "Service lookup failed for source"
+ " port \"%s\"", sports);
+ }
+ }
+ if (sport && dport) {
+ /* Set up a description of the source port. */
+ struct ssh_portfwd *pfrec, *epfrec;
+
+ pfrec = snew(struct ssh_portfwd);
+ pfrec->type = type;
+ pfrec->saddr = *saddr ? dupstr(saddr) : NULL;
+ pfrec->sserv = sserv ? dupstr(sports) : NULL;
+ pfrec->sport = sport;
+ pfrec->daddr = *host ? dupstr(host) : NULL;
+ pfrec->dserv = dserv ? dupstr(dports) : NULL;
+ pfrec->dport = dport;
+ pfrec->local = NULL;
+ pfrec->remote = NULL;
+ pfrec->addressfamily = (address_family == '4' ? ADDRTYPE_IPV4 :
+ address_family == '6' ? ADDRTYPE_IPV6 :
+ ADDRTYPE_UNSPEC);
+
+ epfrec = add234(ssh->portfwds, pfrec);
+ if (epfrec != pfrec) {
+ /*
+ * We already have a port forwarding with precisely
+ * these parameters. Hence, no need to do anything;
+ * simply tag the existing one as KEEP.
+ */
+ epfrec->status = KEEP;
+ free_portfwd(pfrec);
+ } else {
+ pfrec->status = CREATE;
+ }
+ }
+ }
+
+ /*
+ * Now go through and destroy any port forwardings which were
+ * not re-enabled.
+ */
+ for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
+ if (epf->status == DESTROY) {
+ char *message;
+
+ message = dupprintf("%s port forwarding from %s%s%d",
+ epf->type == 'L' ? "local" :
+ epf->type == 'R' ? "remote" : "dynamic",
+ epf->saddr ? epf->saddr : "",
+ epf->saddr ? ":" : "",
+ epf->sport);
+
+ if (epf->type != 'D') {
+ char *msg2 = dupprintf("%s to %s:%d", message,
+ epf->daddr, epf->dport);
+ sfree(message);
+ message = msg2;
+ }
+
+ logeventf(ssh, "Cancelling %s", message);
+ sfree(message);
+
+ if (epf->remote) {
+ struct ssh_rportfwd *rpf = epf->remote;
+ struct Packet *pktout;
+
+ /*
+ * Cancel the port forwarding at the server
+ * end.
+ */
+ if (ssh->version == 1) {
+ /*
+ * We cannot cancel listening ports on the
+ * server side in SSH-1! There's no message
+ * to support it. Instead, we simply remove
+ * the rportfwd record from the local end
+ * so that any connections the server tries
+ * to make on it are rejected.
+ */
+ } else {
+ pktout = ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
+ ssh2_pkt_addstring(pktout, "cancel-tcpip-forward");
+ ssh2_pkt_addbool(pktout, 0);/* _don't_ want reply */
+ if (epf->saddr) {
+ ssh2_pkt_addstring(pktout, epf->saddr);
+ } else if (ssh->cfg.rport_acceptall) {
+ /* XXX: ssh->cfg.rport_acceptall may not represent
+ * what was used to open the original connection,
+ * since it's reconfigurable. */
+ ssh2_pkt_addstring(pktout, "0.0.0.0");
+ } else {
+ ssh2_pkt_addstring(pktout, "127.0.0.1");
+ }
+ ssh2_pkt_adduint32(pktout, epf->sport);
+ ssh2_pkt_send(ssh, pktout);
+ }
+
+ del234(ssh->rportfwds, rpf);
+ free_rportfwd(rpf);
+ } else if (epf->local) {
+ pfd_terminate(epf->local);
+ }
+
+ delpos234(ssh->portfwds, i);
+ free_portfwd(epf);
+ i--; /* so we don't skip one in the list */
+ }
+
+ /*
+ * And finally, set up any new port forwardings (status==CREATE).
+ */
+ for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
+ if (epf->status == CREATE) {
+ char *sportdesc, *dportdesc;
+ sportdesc = dupprintf("%s%s%s%s%d%s",
+ epf->saddr ? epf->saddr : "",
+ epf->saddr ? ":" : "",
+ epf->sserv ? epf->sserv : "",
+ epf->sserv ? "(" : "",
+ epf->sport,
+ epf->sserv ? ")" : "");
+ if (epf->type == 'D') {
+ dportdesc = NULL;
+ } else {
+ dportdesc = dupprintf("%s:%s%s%d%s",
+ epf->daddr,
+ epf->dserv ? epf->dserv : "",
+ epf->dserv ? "(" : "",
+ epf->dport,
+ epf->dserv ? ")" : "");
+ }
+
+ if (epf->type == 'L') {
+ const char *err = pfd_addforward(epf->daddr, epf->dport,
+ epf->saddr, epf->sport,
+ ssh, cfg,
+ &epf->local,
+ epf->addressfamily);
+
+ logeventf(ssh, "Local %sport %s forwarding to %s%s%s",
+ epf->addressfamily == ADDRTYPE_IPV4 ? "IPv4 " :
+ epf->addressfamily == ADDRTYPE_IPV6 ? "IPv6 " : "",
+ sportdesc, dportdesc,
+ err ? " failed: " : "", err ? err : "");
+ } else if (epf->type == 'D') {
+ const char *err = pfd_addforward(NULL, -1,
+ epf->saddr, epf->sport,
+ ssh, cfg,
+ &epf->local,
+ epf->addressfamily);
+
+ logeventf(ssh, "Local %sport %s SOCKS dynamic forwarding%s%s",
+ epf->addressfamily == ADDRTYPE_IPV4 ? "IPv4 " :
+ epf->addressfamily == ADDRTYPE_IPV6 ? "IPv6 " : "",
+ sportdesc,
+ err ? " failed: " : "", err ? err : "");
+ } else {
+ struct ssh_rportfwd *pf;
+
+ /*
+ * Ensure the remote port forwardings tree exists.
+ */
+ if (!ssh->rportfwds) {
+ if (ssh->version == 1)
+ ssh->rportfwds = newtree234(ssh_rportcmp_ssh1);
+ else
+ ssh->rportfwds = newtree234(ssh_rportcmp_ssh2);
+ }
+
+ pf = snew(struct ssh_rportfwd);
+ strncpy(pf->dhost, epf->daddr, lenof(pf->dhost)-1);
+ pf->dhost[lenof(pf->dhost)-1] = '\0';
+ pf->dport = epf->dport;
+ pf->sport = epf->sport;
+ if (add234(ssh->rportfwds, pf) != pf) {
+ logeventf(ssh, "Duplicate remote port forwarding to %s:%d",
+ epf->daddr, epf->dport);
+ sfree(pf);
+ } else {
+ logeventf(ssh, "Requesting remote port %s"
+ " forward to %s", sportdesc, dportdesc);
+
+ pf->sportdesc = sportdesc;
+ sportdesc = NULL;
+ epf->remote = pf;
+ pf->pfrec = epf;
+
+ if (ssh->version == 1) {
+ send_packet(ssh, SSH1_CMSG_PORT_FORWARD_REQUEST,
+ PKT_INT, epf->sport,
+ PKT_STR, epf->daddr,
+ PKT_INT, epf->dport,
+ PKT_END);
+ ssh_queue_handler(ssh, SSH1_SMSG_SUCCESS,
+ SSH1_SMSG_FAILURE,
+ ssh_rportfwd_succfail, pf);
+ } else {
+ struct Packet *pktout;
+ pktout = ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
+ ssh2_pkt_addstring(pktout, "tcpip-forward");
+ ssh2_pkt_addbool(pktout, 1);/* want reply */
+ if (epf->saddr) {
+ ssh2_pkt_addstring(pktout, epf->saddr);
+ } else if (cfg->rport_acceptall) {
+ ssh2_pkt_addstring(pktout, "0.0.0.0");
+ } else {
+ ssh2_pkt_addstring(pktout, "127.0.0.1");
+ }
+ ssh2_pkt_adduint32(pktout, epf->sport);
+ ssh2_pkt_send(ssh, pktout);
+
+ ssh_queue_handler(ssh, SSH2_MSG_REQUEST_SUCCESS,
+ SSH2_MSG_REQUEST_FAILURE,
+ ssh_rportfwd_succfail, pf);
+ }
+ }
+ }
+ sfree(sportdesc);
+ sfree(dportdesc);
+ }
+}
+
static void ssh1_smsg_stdout_stderr_data(Ssh ssh, struct Packet *pktin)
{
char *string;
logevent
("Opening X11 forward connection succeeded");
c->remoteid = remoteid;
+ c->halfopen = FALSE;
c->localid = alloc_channel_id(ssh);
c->closes = 0;
c->v.v1.throttling = 0;
c = snew(struct ssh_channel);
c->ssh = ssh;
c->remoteid = remoteid;
+ c->halfopen = FALSE;
c->localid = alloc_channel_id(ssh);
c->closes = 0;
c->v.v1.throttling = 0;
/* Remote side is trying to open a channel to talk to a
* forwarded port. Give them back a local channel number. */
struct ssh_channel *c;
- struct ssh_rportfwd pf;
+ struct ssh_rportfwd pf, *pfp;
int remoteid;
int hostsize, port;
- char *host, buf[1024];
+ char *host;
const char *e;
c = snew(struct ssh_channel);
c->ssh = ssh;
memcpy(pf.dhost, host, hostsize);
pf.dhost[hostsize] = '\0';
pf.dport = port;
+ pfp = find234(ssh->rportfwds, &pf, NULL);
- if (find234(ssh->rportfwds, &pf, NULL) == NULL) {
- sprintf(buf, "Rejected remote port open request for %s:%d",
- pf.dhost, port);
- logevent(buf);
+ if (pfp == NULL) {
+ logeventf(ssh, "Rejected remote port open request for %s:%d",
+ pf.dhost, port);
send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
PKT_INT, remoteid, PKT_END);
} else {
- sprintf(buf, "Received remote port open request for %s:%d",
- pf.dhost, port);
- logevent(buf);
+ logeventf(ssh, "Received remote port open request for %s:%d",
+ pf.dhost, port);
e = pfd_newconnect(&c->u.pfd.s, pf.dhost, port,
- c, &ssh->cfg);
+ c, &ssh->cfg, pfp->pfrec->addressfamily);
if (e != NULL) {
- char buf[256];
- sprintf(buf, "Port open failed: %s", e);
- logevent(buf);
+ logeventf(ssh, "Port open failed: %s", e);
sfree(c);
send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
PKT_INT, remoteid, PKT_END);
} else {
c->remoteid = remoteid;
+ c->halfopen = FALSE;
c->localid = alloc_channel_id(ssh);
c->closes = 0;
c->v.v1.throttling = 0;
c = find234(ssh->channels, &remoteid, ssh_channelfind);
if (c && c->type == CHAN_SOCKDATA_DORMANT) {
c->remoteid = localid;
+ c->halfopen = FALSE;
c->type = CHAN_SOCKDATA;
c->v.v1.throttling = 0;
pfd_confirm(c->u.pfd.s);
unsigned i = ssh_pkt_getuint32(pktin);
struct ssh_channel *c;
c = find234(ssh->channels, &i, ssh_channelfind);
- if (c && ((int)c->remoteid) != -1) {
+ if (c && !c->halfopen) {
int closetype;
closetype =
(pktin->type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
/* Data for an agent message. Buffer it. */
while (len > 0) {
if (c->u.a.lensofar < 4) {
- int l = min(4 - c->u.a.lensofar, len);
+ unsigned int l = min(4 - c->u.a.lensofar, len);
memcpy(c->u.a.msglen + c->u.a.lensofar, p,
l);
p += l;
memcpy(c->u.a.message, c->u.a.msglen, 4);
}
if (c->u.a.lensofar >= 4 && len > 0) {
- int l =
+ unsigned int l =
min(c->u.a.totallen - c->u.a.lensofar,
len);
memcpy(c->u.a.message + c->u.a.lensofar, p,
static void ssh1_smsg_exit_status(Ssh ssh, struct Packet *pktin)
{
- char buf[100];
ssh->exitcode = ssh_pkt_getuint32(pktin);
- sprintf(buf, "Server sent command exit status %d",
- ssh->exitcode);
- logevent(buf);
+ logeventf(ssh, "Server sent command exit status %d", ssh->exitcode);
send_packet(ssh, SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
/*
* In case `helpful' firewalls or proxies tack
* encrypted packet, we close the session once
* we've sent EXIT_CONFIRMATION.
*/
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, NULL, NULL, 0, TRUE);
+}
+
+/* Helper function to deal with sending tty modes for REQUEST_PTY */
+static void ssh1_send_ttymode(void *data, char *mode, char *val)
+{
+ struct Packet *pktout = (struct Packet *)data;
+ int i = 0;
+ unsigned int arg = 0;
+ while (strcmp(mode, ssh_ttymodes[i].mode) != 0) i++;
+ if (i == lenof(ssh_ttymodes)) return;
+ switch (ssh_ttymodes[i].type) {
+ case TTY_OP_CHAR:
+ arg = ssh_tty_parse_specchar(val);
+ break;
+ case TTY_OP_BOOL:
+ arg = ssh_tty_parse_boolean(val);
+ break;
+ }
+ ssh2_pkt_addbyte(pktout, ssh_ttymodes[i].opcode);
+ ssh2_pkt_addbyte(pktout, arg);
}
+
static void do_ssh1_connection(Ssh ssh, unsigned char *in, int inlen,
struct Packet *pktin)
{
ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
data, sizeof(data), ssh->cfg.x11_auth);
x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
+ /*
+ * Note that while we blank the X authentication data here, we don't
+ * take any special action to blank the start of an X11 channel,
+ * so using MIT-MAGIC-COOKIE-1 and actually opening an X connection
+ * without having session blanking enabled is likely to leak your
+ * cookie into the log.
+ */
if (ssh->v1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
- PKT_STR, proto, PKT_STR, data,
+ PKT_STR, proto,
+ PKTT_PASSWORD, PKT_STR, data, PKTT_OTHER,
PKT_INT, x11_get_screen_number(ssh->cfg.x11_display),
PKT_END);
} else {
send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
- PKT_STR, proto, PKT_STR, data, PKT_END);
+ PKT_STR, proto,
+ PKTT_PASSWORD, PKT_STR, data, PKTT_OTHER, PKT_END);
}
do {
crReturnV;
&& pktin->type != SSH1_SMSG_FAILURE) {
bombout(("Protocol confusion"));
crStopV;
- } else if (pktin->type == SSH1_SMSG_FAILURE) {
- logevent("X11 forwarding refused");
- } else {
- logevent("X11 forwarding enabled");
- ssh->X11_fwd_enabled = TRUE;
- ssh->packet_dispatch[SSH1_SMSG_X11_OPEN] = ssh1_smsg_x11_open;
- }
- }
-
- {
- char type;
- int n;
- int sport,dport,sserv,dserv;
- char sports[256], dports[256], saddr[256], host[256];
-
- ssh->rportfwds = newtree234(ssh_rportcmp_ssh1);
- /* Add port forwardings. */
- ssh->portfwd_strptr = ssh->cfg.portfwd;
- while (*ssh->portfwd_strptr) {
- type = *ssh->portfwd_strptr++;
- saddr[0] = '\0';
- n = 0;
- while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t') {
- if (*ssh->portfwd_strptr == ':') {
- /*
- * We've seen a colon in the middle of the
- * source port number. This means that
- * everything we've seen until now is the
- * source _address_, so we'll move it into
- * saddr and start sports from the beginning
- * again.
- */
- ssh->portfwd_strptr++;
- sports[n] = '\0';
- strcpy(saddr, sports);
- n = 0;
- }
- if (n < 255) sports[n++] = *ssh->portfwd_strptr++;
- }
- sports[n] = 0;
- if (type != 'D') {
- if (*ssh->portfwd_strptr == '\t')
- ssh->portfwd_strptr++;
- n = 0;
- while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':') {
- if (n < 255) host[n++] = *ssh->portfwd_strptr++;
- }
- host[n] = 0;
- if (*ssh->portfwd_strptr == ':')
- ssh->portfwd_strptr++;
- n = 0;
- while (*ssh->portfwd_strptr) {
- if (n < 255) dports[n++] = *ssh->portfwd_strptr++;
- }
- dports[n] = 0;
- ssh->portfwd_strptr++;
- dport = atoi(dports);
- dserv = 0;
- if (dport == 0) {
- dserv = 1;
- dport = net_service_lookup(dports);
- if (!dport) {
- logeventf(ssh, "Service lookup failed for"
- " destination port \"%s\"", dports);
- }
- }
- } else {
- while (*ssh->portfwd_strptr) ssh->portfwd_strptr++;
- dport = dserv = -1;
- ssh->portfwd_strptr++; /* eat the NUL and move to next one */
- }
- sport = atoi(sports);
- sserv = 0;
- if (sport == 0) {
- sserv = 1;
- sport = net_service_lookup(sports);
- if (!sport) {
- logeventf(ssh, "Service lookup failed for source"
- " port \"%s\"", sports);
- }
- }
- if (sport && dport) {
- /* Set up a description of the source port. */
- static char *sportdesc;
- sportdesc = dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
- (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
- (int)(*saddr?1:0), ":",
- (int)(sserv ? strlen(sports) : 0), sports,
- sserv, "(", sport, sserv, ")");
- if (type == 'L') {
- /* Verbose description of the destination port */
- char *dportdesc = dupprintf("%s:%.*s%.*s%d%.*s",
- host,
- (int)(dserv ? strlen(dports) : 0), dports,
- dserv, "(", dport, dserv, ")");
- const char *err = pfd_addforward(host, dport,
- *saddr ? saddr : NULL,
- sport, ssh, &ssh->cfg);
- if (err) {
- logeventf(ssh, "Local port %s forward to %s"
- " failed: %s", sportdesc, dportdesc, err);
- } else {
- logeventf(ssh, "Local port %s forwarding to %s",
- sportdesc, dportdesc);
- }
- sfree(dportdesc);
- } else if (type == 'D') {
- const char *err = pfd_addforward(NULL, -1,
- *saddr ? saddr : NULL,
- sport, ssh, &ssh->cfg);
- if (err) {
- logeventf(ssh, "Local port %s SOCKS dynamic forward"
- " setup failed: %s", sportdesc, err);
- } else {
- logeventf(ssh, "Local port %s doing SOCKS"
- " dynamic forwarding", sportdesc);
- }
- } else {
- struct ssh_rportfwd *pf;
- pf = snew(struct ssh_rportfwd);
- strcpy(pf->dhost, host);
- pf->dport = dport;
- if (*saddr) {
- logeventf(ssh,
- "SSH1 cannot handle source address spec \"%s:%d\"; ignoring",
- saddr, sport);
- }
- if (add234(ssh->rportfwds, pf) != pf) {
- logeventf(ssh,
- "Duplicate remote port forwarding to %s:%d",
- host, dport);
- sfree(pf);
- } else {
- logeventf(ssh, "Requesting remote port %.*s%.*s%d%.*s"
- " forward to %s:%.*s%.*s%d%.*s",
- (int)(sserv ? strlen(sports) : 0), sports,
- sserv, "(", sport, sserv, ")",
- host,
- (int)(dserv ? strlen(dports) : 0), dports,
- dserv, "(", dport, dserv, ")");
- send_packet(ssh, SSH1_CMSG_PORT_FORWARD_REQUEST,
- PKT_INT, sport,
- PKT_STR, host,
- PKT_INT, dport,
- PKT_END);
- do {
- crReturnV;
- } while (!pktin);
- if (pktin->type != SSH1_SMSG_SUCCESS
- && pktin->type != SSH1_SMSG_FAILURE) {
- bombout(("Protocol confusion"));
- crStopV;
- } else if (pktin->type == SSH1_SMSG_FAILURE) {
- c_write_str(ssh, "Server refused port"
- " forwarding\r\n");
- logevent("Server refused this port forwarding");
- } else {
- logevent("Remote port forwarding enabled");
- ssh->packet_dispatch[SSH1_MSG_PORT_OPEN] =
- ssh1_msg_port_open;
- }
- }
- }
- sfree(sportdesc);
- }
+ } else if (pktin->type == SSH1_SMSG_FAILURE) {
+ logevent("X11 forwarding refused");
+ } else {
+ logevent("X11 forwarding enabled");
+ ssh->X11_fwd_enabled = TRUE;
+ ssh->packet_dispatch[SSH1_SMSG_X11_OPEN] = ssh1_smsg_x11_open;
}
}
+ ssh_setup_portfwd(ssh, &ssh->cfg);
+ ssh->packet_dispatch[SSH1_MSG_PORT_OPEN] = ssh1_msg_port_open;
+
if (!ssh->cfg.nopty) {
+ struct Packet *pkt;
/* Unpick the terminal-speed string. */
/* XXX perhaps we should allow no speeds to be sent. */
ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
/* Send the pty request. */
- send_packet(ssh, SSH1_CMSG_REQUEST_PTY,
- PKT_STR, ssh->cfg.termtype,
- PKT_INT, ssh->term_height,
- PKT_INT, ssh->term_width,
- PKT_INT, 0, PKT_INT, 0, /* width,height in pixels */
- PKT_CHAR, 192, PKT_INT, ssh->ispeed, /* TTY_OP_ISPEED */
- PKT_CHAR, 193, PKT_INT, ssh->ospeed, /* TTY_OP_OSPEED */
- PKT_CHAR, 0, PKT_END);
+ pkt = ssh1_pkt_init(SSH1_CMSG_REQUEST_PTY);
+ ssh_pkt_addstring(pkt, ssh->cfg.termtype);
+ ssh_pkt_adduint32(pkt, ssh->term_height);
+ ssh_pkt_adduint32(pkt, ssh->term_width);
+ ssh_pkt_adduint32(pkt, 0); /* width in pixels */
+ ssh_pkt_adduint32(pkt, 0); /* height in pixels */
+ parse_ttymodes(ssh, ssh->cfg.ttymodes,
+ ssh1_send_ttymode, (void *)pkt);
+ ssh_pkt_addbyte(pkt, SSH1_TTY_OP_ISPEED);
+ ssh_pkt_adduint32(pkt, ssh->ispeed);
+ ssh_pkt_addbyte(pkt, SSH1_TTY_OP_OSPEED);
+ ssh_pkt_adduint32(pkt, ssh->ospeed);
+ ssh_pkt_addbyte(pkt, SSH_TTY_OP_END);
+ s_wrpkt(ssh, pkt);
ssh->state = SSH_STATE_INTERMED;
do {
crReturnV;
/*
* Start the shell or command.
*
- * Special case: if the first-choice command is an SSH2
+ * Special case: if the first-choice command is an SSH-2
* subsystem (hence not usable here) and the second choice
* exists, we fall straight back to that.
*/
{
char *cmd = ssh->cfg.remote_cmd_ptr;
+
+ if (!cmd) cmd = ssh->cfg.remote_cmd;
if (ssh->cfg.ssh_subsys && ssh->cfg.remote_cmd_ptr2) {
cmd = ssh->cfg.remote_cmd_ptr2;
}
/*
- * Handle the top-level SSH2 protocol.
+ * Handle the top-level SSH-2 protocol.
*/
static void ssh1_msg_debug(Ssh ssh, struct Packet *pktin)
{
- char *buf, *msg;
+ char *msg;
int msglen;
ssh_pkt_getstring(pktin, &msg, &msglen);
- buf = dupprintf("Remote debug message: %.*s", msglen, msg);
- logevent(buf);
- sfree(buf);
+ logeventf(ssh, "Remote debug message: %.*s", msglen, msg);
}
static void ssh1_msg_disconnect(Ssh ssh, struct Packet *pktin)
bombout(("Server sent disconnect message:\n\"%.*s\"", msglen, msg));
}
-void ssh_msg_ignore(Ssh ssh, struct Packet *pktin)
+static void ssh_msg_ignore(Ssh ssh, struct Packet *pktin)
{
/* Do nothing, because we're ignoring it! Duhh. */
}
ssh->packet_dispatch[SSH1_MSG_DEBUG] = ssh1_msg_debug;
}
-static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen,
+static void ssh1_protocol(Ssh ssh, void *vin, int inlen,
struct Packet *pktin)
{
+ unsigned char *in=(unsigned char*)vin;
if (ssh->state == SSH_STATE_CLOSED)
return;
}
/*
- * SSH2 key creation method.
+ * Similar routine for checking whether we have the first string in a list.
+ */
+static int first_in_commasep_string(char *needle, char *haystack, int haylen)
+{
+ int needlen;
+ if (!needle || !haystack) /* protect against null pointers */
+ return 0;
+ needlen = strlen(needle);
+ /*
+ * Is it at the start of the string?
+ */
+ if (haylen >= needlen && /* haystack is long enough */
+ !memcmp(needle, haystack, needlen) && /* initial match */
+ (haylen == needlen || haystack[needlen] == ',')
+ /* either , or EOS follows */
+ )
+ return 1;
+ return 0;
+}
+
+
+/*
+ * SSH-2 key creation method.
*/
-static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H,
- unsigned char *sessid, char chr,
+static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H, char chr,
unsigned char *keyspace)
{
- SHA_State s;
- /* First 20 bytes. */
- SHA_Init(&s);
+ const struct ssh_hash *h = ssh->kex->hash;
+ void *s;
+ /* First hlen bytes. */
+ s = h->init();
if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
- sha_mpint(&s, K);
- SHA_Bytes(&s, H, 20);
- SHA_Bytes(&s, &chr, 1);
- SHA_Bytes(&s, sessid, 20);
- SHA_Final(&s, keyspace);
- /* Next 20 bytes. */
- SHA_Init(&s);
+ hash_mpint(h, s, K);
+ h->bytes(s, H, h->hlen);
+ h->bytes(s, &chr, 1);
+ h->bytes(s, ssh->v2_session_id, ssh->v2_session_id_len);
+ h->final(s, keyspace);
+ /* Next hlen bytes. */
+ s = h->init();
if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
- sha_mpint(&s, K);
- SHA_Bytes(&s, H, 20);
- SHA_Bytes(&s, keyspace, 20);
- SHA_Final(&s, keyspace + 20);
+ hash_mpint(h, s, K);
+ h->bytes(s, H, h->hlen);
+ h->bytes(s, keyspace, h->hlen);
+ h->final(s, keyspace + h->hlen);
}
/*
- * Handle the SSH2 transport layer.
+ * Handle the SSH-2 transport layer.
*/
-static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
+static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
struct Packet *pktin)
{
+ unsigned char *in = (unsigned char *)vin;
struct do_ssh2_transport_state {
- int nbits, pbits, warn;
+ int nbits, pbits, warn_kex, warn_cscipher, warn_sccipher;
Bignum p, g, e, f, K;
+ void *our_kexinit;
+ int our_kexinitlen;
int kex_init_value, kex_reply_value;
const struct ssh_mac **maclist;
int nmacs;
char *hostkeydata, *sigdata, *keystr, *fingerprint;
int hostkeylen, siglen;
void *hkey; /* actual host key */
- unsigned char exchange_hash[20];
+ unsigned char exchange_hash[32];
+ int n_preferred_kex;
+ const struct ssh_kexes *preferred_kex[KEX_MAX];
int n_preferred_ciphers;
const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
const struct ssh_compress *preferred_comp;
- int first_kex;
+ int got_session_id, activated_authconn;
struct Packet *pktout;
+ int dlgret;
+ int guessok;
+ int ignorepkt;
};
crState(do_ssh2_transport_state);
s->csmac_tobe = s->scmac_tobe = NULL;
s->cscomp_tobe = s->sccomp_tobe = NULL;
- s->first_kex = 1;
+ s->got_session_id = s->activated_authconn = FALSE;
+
+ /*
+ * Be prepared to work around the buggy MAC problem.
+ */
+ if (ssh->remote_bugs & BUG_SSH2_HMAC)
+ s->maclist = buggymacs, s->nmacs = lenof(buggymacs);
+ else
+ s->maclist = macs, s->nmacs = lenof(macs);
+ begin_key_exchange:
+ ssh->pkt_ctx &= ~SSH2_PKTCTX_KEX_MASK;
{
- int i;
+ int i, j, commalist_started;
+
+ /*
+ * Set up the preferred key exchange. (NULL => warn below here)
+ */
+ s->n_preferred_kex = 0;
+ for (i = 0; i < KEX_MAX; i++) {
+ switch (ssh->cfg.ssh_kexlist[i]) {
+ case KEX_DHGEX:
+ s->preferred_kex[s->n_preferred_kex++] =
+ &ssh_diffiehellman_gex;
+ break;
+ case KEX_DHGROUP14:
+ s->preferred_kex[s->n_preferred_kex++] =
+ &ssh_diffiehellman_group14;
+ break;
+ case KEX_DHGROUP1:
+ s->preferred_kex[s->n_preferred_kex++] =
+ &ssh_diffiehellman_group1;
+ break;
+ case CIPHER_WARN:
+ /* Flag for later. Don't bother if it's the last in
+ * the list. */
+ if (i < KEX_MAX - 1) {
+ s->preferred_kex[s->n_preferred_kex++] = NULL;
+ }
+ break;
+ }
+ }
+
/*
* Set up the preferred ciphers. (NULL => warn below here)
*/
case CIPHER_AES:
s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_aes;
break;
+ case CIPHER_ARCFOUR:
+ s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_arcfour;
+ break;
case CIPHER_WARN:
/* Flag for later. Don't bother if it's the last in
* the list. */
break;
}
}
- }
-
- /*
- * Set up preferred compression.
- */
- if (ssh->cfg.compression)
- s->preferred_comp = &ssh_zlib;
- else
- s->preferred_comp = &ssh_comp_none;
-
- /*
- * Be prepared to work around the buggy MAC problem.
- */
- if (ssh->remote_bugs & BUG_SSH2_HMAC)
- s->maclist = buggymacs, s->nmacs = lenof(buggymacs);
- else
- s->maclist = macs, s->nmacs = lenof(macs);
- begin_key_exchange:
- {
- int i, j, cipherstr_started;
+ /*
+ * Set up preferred compression.
+ */
+ if (ssh->cfg.compression)
+ s->preferred_comp = &ssh_zlib;
+ else
+ s->preferred_comp = &ssh_comp_none;
/*
* Enable queueing of outgoing auth- or connection-layer
ssh2_pkt_addbyte(s->pktout, (unsigned char) random_byte());
/* List key exchange algorithms. */
ssh2_pkt_addstring_start(s->pktout);
- for (i = 0; i < lenof(kex_algs); i++) {
- if (kex_algs[i] == &ssh_diffiehellman_gex &&
- (ssh->remote_bugs & BUG_SSH2_DH_GEX))
- continue;
- ssh2_pkt_addstring_str(s->pktout, kex_algs[i]->name);
- if (i < lenof(kex_algs) - 1)
- ssh2_pkt_addstring_str(s->pktout, ",");
+ commalist_started = 0;
+ for (i = 0; i < s->n_preferred_kex; i++) {
+ const struct ssh_kexes *k = s->preferred_kex[i];
+ if (!k) continue; /* warning flag */
+ for (j = 0; j < k->nkexes; j++) {
+ if (commalist_started)
+ ssh2_pkt_addstring_str(s->pktout, ",");
+ ssh2_pkt_addstring_str(s->pktout, k->list[j]->name);
+ commalist_started = 1;
+ }
}
/* List server host key algorithms. */
ssh2_pkt_addstring_start(s->pktout);
}
/* List client->server encryption algorithms. */
ssh2_pkt_addstring_start(s->pktout);
- cipherstr_started = 0;
+ commalist_started = 0;
for (i = 0; i < s->n_preferred_ciphers; i++) {
const struct ssh2_ciphers *c = s->preferred_ciphers[i];
if (!c) continue; /* warning flag */
for (j = 0; j < c->nciphers; j++) {
- if (cipherstr_started)
+ if (commalist_started)
ssh2_pkt_addstring_str(s->pktout, ",");
ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
- cipherstr_started = 1;
+ commalist_started = 1;
}
}
/* List server->client encryption algorithms. */
ssh2_pkt_addstring_start(s->pktout);
- cipherstr_started = 0;
+ commalist_started = 0;
for (i = 0; i < s->n_preferred_ciphers; i++) {
const struct ssh2_ciphers *c = s->preferred_ciphers[i];
if (!c) continue; /* warning flag */
for (j = 0; j < c->nciphers; j++) {
- if (cipherstr_started)
+ if (commalist_started)
ssh2_pkt_addstring_str(s->pktout, ",");
ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
- cipherstr_started = 1;
+ commalist_started = 1;
}
}
/* List client->server MAC algorithms. */
ssh2_pkt_adduint32(s->pktout, 0);
}
- ssh->exhash = ssh->exhashbase;
- sha_string(&ssh->exhash, s->pktout->data + 5, s->pktout->length - 5);
+ s->our_kexinitlen = s->pktout->length - 5;
+ s->our_kexinit = snewn(s->our_kexinitlen, unsigned char);
+ memcpy(s->our_kexinit, s->pktout->data + 5, s->our_kexinitlen);
ssh2_pkt_send_noqueue(ssh, s->pktout);
if (!pktin)
crWaitUntil(pktin);
- if (pktin->length > 5)
- sha_string(&ssh->exhash, pktin->data + 5, pktin->length - 5);
/*
* Now examine the other side's KEXINIT to see what we're up
* to.
*/
{
- char *str;
+ char *str, *preferred;
int i, j, len;
if (pktin->type != SSH2_MSG_KEXINIT) {
s->scmac_tobe = NULL;
s->cscomp_tobe = NULL;
s->sccomp_tobe = NULL;
+ s->warn_kex = s->warn_cscipher = s->warn_sccipher = FALSE;
+
pktin->savedpos += 16; /* skip garbage cookie */
ssh_pkt_getstring(pktin, &str, &len); /* key exchange algorithms */
- for (i = 0; i < lenof(kex_algs); i++) {
- if (kex_algs[i] == &ssh_diffiehellman_gex &&
- (ssh->remote_bugs & BUG_SSH2_DH_GEX))
- continue;
- if (in_commasep_string(kex_algs[i]->name, str, len)) {
- ssh->kex = kex_algs[i];
- break;
+
+ preferred = NULL;
+ for (i = 0; i < s->n_preferred_kex; i++) {
+ const struct ssh_kexes *k = s->preferred_kex[i];
+ if (!k) {
+ s->warn_kex = TRUE;
+ } else {
+ for (j = 0; j < k->nkexes; j++) {
+ if (!preferred) preferred = k->list[j]->name;
+ if (in_commasep_string(k->list[j]->name, str, len)) {
+ ssh->kex = k->list[j];
+ break;
+ }
+ }
}
+ if (ssh->kex)
+ break;
+ }
+ if (!ssh->kex) {
+ bombout(("Couldn't agree a key exchange algorithm (available: %s)",
+ str ? str : "(null)"));
+ crStop(0);
}
+ /*
+ * Note that the server's guess is considered wrong if it doesn't match
+ * the first algorithm in our list, even if it's still the algorithm
+ * we end up using.
+ */
+ s->guessok = first_in_commasep_string(preferred, str, len);
ssh_pkt_getstring(pktin, &str, &len); /* host key algorithms */
for (i = 0; i < lenof(hostkey_algs); i++) {
if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
break;
}
}
+ s->guessok = s->guessok &&
+ first_in_commasep_string(hostkey_algs[0]->name, str, len);
ssh_pkt_getstring(pktin, &str, &len); /* client->server cipher */
- s->warn = 0;
for (i = 0; i < s->n_preferred_ciphers; i++) {
const struct ssh2_ciphers *c = s->preferred_ciphers[i];
if (!c) {
- s->warn = 1;
+ s->warn_cscipher = TRUE;
} else {
for (j = 0; j < c->nciphers; j++) {
if (in_commasep_string(c->list[j]->name, str, len)) {
}
}
}
- if (s->cscipher_tobe) {
- if (s->warn)
- askcipher(ssh->frontend, s->cscipher_tobe->name, 1);
+ if (s->cscipher_tobe)
break;
- }
}
if (!s->cscipher_tobe) {
bombout(("Couldn't agree a client-to-server cipher (available: %s)",
}
ssh_pkt_getstring(pktin, &str, &len); /* server->client cipher */
- s->warn = 0;
for (i = 0; i < s->n_preferred_ciphers; i++) {
const struct ssh2_ciphers *c = s->preferred_ciphers[i];
if (!c) {
- s->warn = 1;
+ s->warn_sccipher = TRUE;
} else {
for (j = 0; j < c->nciphers; j++) {
if (in_commasep_string(c->list[j]->name, str, len)) {
}
}
}
- if (s->sccipher_tobe) {
- if (s->warn)
- askcipher(ssh->frontend, s->sccipher_tobe->name, 2);
+ if (s->sccipher_tobe)
break;
- }
}
if (!s->sccipher_tobe) {
bombout(("Couldn't agree a server-to-client cipher (available: %s)",
break;
}
}
+ ssh_pkt_getstring(pktin, &str, &len); /* client->server language */
+ ssh_pkt_getstring(pktin, &str, &len); /* server->client language */
+ s->ignorepkt = ssh2_pkt_getbool(pktin) && !s->guessok;
+
+ if (s->warn_kex) {
+ ssh_set_frozen(ssh, 1);
+ s->dlgret = askalg(ssh->frontend, "key-exchange algorithm",
+ ssh->kex->name,
+ ssh_dialog_callback, ssh);
+ if (s->dlgret < 0) {
+ do {
+ crReturn(0);
+ if (pktin) {
+ bombout(("Unexpected data from server while"
+ " waiting for user response"));
+ crStop(0);
+ }
+ } while (pktin || inlen > 0);
+ s->dlgret = ssh->user_response;
+ }
+ ssh_set_frozen(ssh, 0);
+ if (s->dlgret == 0) {
+ ssh_disconnect(ssh, "User aborted at kex warning", NULL,
+ 0, TRUE);
+ crStop(0);
+ }
+ }
+
+ if (s->warn_cscipher) {
+ ssh_set_frozen(ssh, 1);
+ s->dlgret = askalg(ssh->frontend,
+ "client-to-server cipher",
+ s->cscipher_tobe->name,
+ ssh_dialog_callback, ssh);
+ if (s->dlgret < 0) {
+ do {
+ crReturn(0);
+ if (pktin) {
+ bombout(("Unexpected data from server while"
+ " waiting for user response"));
+ crStop(0);
+ }
+ } while (pktin || inlen > 0);
+ s->dlgret = ssh->user_response;
+ }
+ ssh_set_frozen(ssh, 0);
+ if (s->dlgret == 0) {
+ ssh_disconnect(ssh, "User aborted at cipher warning", NULL,
+ 0, TRUE);
+ crStop(0);
+ }
+ }
+
+ if (s->warn_sccipher) {
+ ssh_set_frozen(ssh, 1);
+ s->dlgret = askalg(ssh->frontend,
+ "server-to-client cipher",
+ s->sccipher_tobe->name,
+ ssh_dialog_callback, ssh);
+ if (s->dlgret < 0) {
+ do {
+ crReturn(0);
+ if (pktin) {
+ bombout(("Unexpected data from server while"
+ " waiting for user response"));
+ crStop(0);
+ }
+ } while (pktin || inlen > 0);
+ s->dlgret = ssh->user_response;
+ }
+ ssh_set_frozen(ssh, 0);
+ if (s->dlgret == 0) {
+ ssh_disconnect(ssh, "User aborted at cipher warning", NULL,
+ 0, TRUE);
+ crStop(0);
+ }
+ }
+
+ ssh->exhash = ssh->kex->hash->init();
+ hash_string(ssh->kex->hash, ssh->exhash, ssh->v_c, strlen(ssh->v_c));
+ hash_string(ssh->kex->hash, ssh->exhash, ssh->v_s, strlen(ssh->v_s));
+ hash_string(ssh->kex->hash, ssh->exhash,
+ s->our_kexinit, s->our_kexinitlen);
+ sfree(s->our_kexinit);
+ if (pktin->length > 5)
+ hash_string(ssh->kex->hash, ssh->exhash,
+ pktin->data + 5, pktin->length - 5);
+
+ if (s->ignorepkt) /* first_kex_packet_follows */
+ crWaitUntil(pktin); /* Ignore packet */
}
/*
scbits = s->sccipher_tobe->keylen;
s->nbits = (csbits > scbits ? csbits : scbits);
}
- /* The keys only have 160-bit entropy, since they're based on
- * a SHA-1 hash. So cap the key size at 160 bits. */
- if (s->nbits > 160)
- s->nbits = 160;
+ /* The keys only have hlen-bit entropy, since they're based on
+ * a hash. So cap the key size at hlen bits. */
+ if (s->nbits > ssh->kex->hash->hlen * 8)
+ s->nbits = ssh->kex->hash->hlen * 8;
/*
* If we're doing Diffie-Hellman group exchange, start by
/*
* Now generate and send e for Diffie-Hellman.
*/
+ set_busy_status(ssh->frontend, BUSY_CPU); /* this can take a while */
s->e = dh_create_e(ssh->kex_ctx, s->nbits * 2);
s->pktout = ssh2_pkt_init(s->kex_init_value);
ssh2_pkt_addmp(s->pktout, s->e);
ssh2_pkt_send_noqueue(ssh, s->pktout);
+ set_busy_status(ssh->frontend, BUSY_WAITING); /* wait for server */
crWaitUntil(pktin);
if (pktin->type != s->kex_reply_value) {
bombout(("expected key exchange reply packet from server"));
crStop(0);
}
+ set_busy_status(ssh->frontend, BUSY_CPU); /* cogitate */
ssh_pkt_getstring(pktin, &s->hostkeydata, &s->hostkeylen);
s->f = ssh2_pkt_getmp(pktin);
if (!s->f) {
s->K = dh_find_K(ssh->kex_ctx, s->f);
- sha_string(&ssh->exhash, s->hostkeydata, s->hostkeylen);
- if (ssh->kex == &ssh_diffiehellman_gex) {
- sha_uint32(&ssh->exhash, s->pbits);
- sha_mpint(&ssh->exhash, s->p);
- sha_mpint(&ssh->exhash, s->g);
+ /* We assume everything from now on will be quick, and it might
+ * involve user interaction. */
+ set_busy_status(ssh->frontend, BUSY_NOT);
+
+ hash_string(ssh->kex->hash, ssh->exhash, s->hostkeydata, s->hostkeylen);
+ if (!ssh->kex->pdata) {
+ hash_uint32(ssh->kex->hash, ssh->exhash, s->pbits);
+ hash_mpint(ssh->kex->hash, ssh->exhash, s->p);
+ hash_mpint(ssh->kex->hash, ssh->exhash, s->g);
}
- sha_mpint(&ssh->exhash, s->e);
- sha_mpint(&ssh->exhash, s->f);
- sha_mpint(&ssh->exhash, s->K);
- SHA_Final(&ssh->exhash, s->exchange_hash);
+ hash_mpint(ssh->kex->hash, ssh->exhash, s->e);
+ hash_mpint(ssh->kex->hash, ssh->exhash, s->f);
+ hash_mpint(ssh->kex->hash, ssh->exhash, s->K);
+ assert(ssh->kex->hash->hlen <= sizeof(s->exchange_hash));
+ ssh->kex->hash->final(ssh->exhash, s->exchange_hash);
dh_cleanup(ssh->kex_ctx);
ssh->kex_ctx = NULL;
#if 0
debug(("Exchange hash is:\n"));
- dmemdump(s->exchange_hash, 20);
+ dmemdump(s->exchange_hash, ssh->kex->hash->hlen);
#endif
s->hkey = ssh->hostkey->newkey(s->hostkeydata, s->hostkeylen);
if (!s->hkey ||
!ssh->hostkey->verifysig(s->hkey, s->sigdata, s->siglen,
- (char *)s->exchange_hash, 20)) {
+ (char *)s->exchange_hash,
+ ssh->kex->hash->hlen)) {
bombout(("Server's host key did not match the signature supplied"));
crStop(0);
}
*/
s->keystr = ssh->hostkey->fmtkey(s->hkey);
s->fingerprint = ssh->hostkey->fingerprint(s->hkey);
- verify_ssh_host_key(ssh->frontend,
- ssh->savedhost, ssh->savedport, ssh->hostkey->keytype,
- s->keystr, s->fingerprint);
- if (s->first_kex) { /* don't bother logging this in rekeys */
+ ssh_set_frozen(ssh, 1);
+ s->dlgret = verify_ssh_host_key(ssh->frontend,
+ ssh->savedhost, ssh->savedport,
+ ssh->hostkey->keytype, s->keystr,
+ s->fingerprint,
+ ssh_dialog_callback, ssh);
+ if (s->dlgret < 0) {
+ do {
+ crReturn(0);
+ if (pktin) {
+ bombout(("Unexpected data from server while waiting"
+ " for user host key response"));
+ crStop(0);
+ }
+ } while (pktin || inlen > 0);
+ s->dlgret = ssh->user_response;
+ }
+ ssh_set_frozen(ssh, 0);
+ if (s->dlgret == 0) {
+ ssh_disconnect(ssh, "User aborted at host key verification", NULL,
+ 0, TRUE);
+ crStop(0);
+ }
+ if (!s->got_session_id) { /* don't bother logging this in rekeys */
logevent("Host key fingerprint is:");
logevent(s->fingerprint);
}
* the session id, used in session key construction and
* authentication.
*/
- if (s->first_kex)
+ if (!s->got_session_id) {
+ assert(sizeof(s->exchange_hash) <= sizeof(ssh->v2_session_id));
memcpy(ssh->v2_session_id, s->exchange_hash,
sizeof(s->exchange_hash));
+ ssh->v2_session_id_len = ssh->kex->hash->hlen;
+ assert(ssh->v2_session_id_len <= sizeof(ssh->v2_session_id));
+ s->got_session_id = TRUE;
+ }
/*
* Send SSH2_MSG_NEWKEYS.
*/
{
unsigned char keyspace[40];
- ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'C',keyspace);
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,'C',keyspace);
ssh->cscipher->setkey(ssh->cs_cipher_ctx, keyspace);
- ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'A',keyspace);
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,'A',keyspace);
ssh->cscipher->setiv(ssh->cs_cipher_ctx, keyspace);
- ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'E',keyspace);
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,'E',keyspace);
ssh->csmac->setkey(ssh->cs_mac_ctx, keyspace);
}
*/
{
unsigned char keyspace[40];
- ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'D',keyspace);
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,'D',keyspace);
ssh->sccipher->setkey(ssh->sc_cipher_ctx, keyspace);
- ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'B',keyspace);
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,'B',keyspace);
ssh->sccipher->setiv(ssh->sc_cipher_ctx, keyspace);
- ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'F',keyspace);
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,'F',keyspace);
ssh->scmac->setkey(ssh->sc_mac_ctx, keyspace);
}
logeventf(ssh, "Initialised %.200s server->client encryption",
*/
freebn(s->f);
freebn(s->K);
- if (ssh->kex == &ssh_diffiehellman_gex) {
+ if (!ssh->kex->pdata) {
freebn(s->g);
freebn(s->p);
}
/*
- * Key exchange is over. Schedule a timer for our next rekey.
+ * Key exchange is over. Loop straight back round if we have a
+ * deferred rekey reason.
+ */
+ if (ssh->deferred_rekey_reason) {
+ logevent(ssh->deferred_rekey_reason);
+ pktin = NULL;
+ ssh->deferred_rekey_reason = NULL;
+ goto begin_key_exchange;
+ }
+
+ /*
+ * Otherwise, schedule a timer for our next rekey.
*/
ssh->kex_in_progress = FALSE;
- ssh->next_rekey = schedule_timer(REKEY_TIMEOUT, ssh2_timer, ssh);
+ ssh->last_rekey = GETTICKCOUNT();
+ if (ssh->cfg.ssh_rekey_time != 0)
+ ssh->next_rekey = schedule_timer(ssh->cfg.ssh_rekey_time*60*TICKSPERSEC,
+ ssh2_timer, ssh);
/*
* If this is the first key exchange phase, we must pass the
* exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
* it would only confuse the layer above.
*/
- if (!s->first_kex) {
- crReturn(1);
+ if (s->activated_authconn) {
+ crReturn(0);
}
- s->first_kex = 0;
+ s->activated_authconn = TRUE;
/*
* Now we're encrypting. Begin returning 1 to the protocol main
*/
while (!((pktin && pktin->type == SSH2_MSG_KEXINIT) ||
(!pktin && inlen == -1))) {
+ wait_for_rekey:
crReturn(1);
}
if (pktin) {
logevent("Server initiated key re-exchange");
} else {
- logevent((char *)in);
+ /*
+ * Special case: if the server bug is set that doesn't
+ * allow rekeying, we give a different log message and
+ * continue waiting. (If such a server _initiates_ a rekey,
+ * we process it anyway!)
+ */
+ if ((ssh->remote_bugs & BUG_SSH2_REKEY)) {
+ logeventf(ssh, "Server bug prevents key re-exchange (%s)",
+ (char *)in);
+ /* Reset the counters, so that at least this message doesn't
+ * hit the event log _too_ often. */
+ ssh->outgoing_data_size = 0;
+ ssh->incoming_data_size = 0;
+ if (ssh->cfg.ssh_rekey_time != 0) {
+ ssh->next_rekey =
+ schedule_timer(ssh->cfg.ssh_rekey_time*60*TICKSPERSEC,
+ ssh2_timer, ssh);
+ }
+ goto wait_for_rekey; /* this is utterly horrid */
+ } else {
+ logeventf(ssh, "Initiating key re-exchange (%s)", (char *)in);
+ }
}
goto begin_key_exchange;
}
/*
- * Add data to an SSH2 channel output buffer.
+ * Add data to an SSH-2 channel output buffer.
*/
static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
int len)
}
/*
- * Attempt to send data on an SSH2 channel.
+ * Attempt to send data on an SSH-2 channel.
*/
static int ssh2_try_send(struct ssh_channel *c)
{
return bufchain_size(&c->v.v2.outbuffer);
}
+static void ssh2_try_send_and_unthrottle(struct ssh_channel *c)
+{
+ int bufsize;
+ if (c->closes)
+ return; /* don't send on closing channels */
+ bufsize = ssh2_try_send(c);
+ if (bufsize == 0) {
+ switch (c->type) {
+ case CHAN_MAINSESSION:
+ /* stdin need not receive an unthrottle
+ * notification since it will be polled */
+ break;
+ case CHAN_X11:
+ x11_unthrottle(c->u.x11.s);
+ break;
+ case CHAN_AGENT:
+ /* agent sockets are request/response and need no
+ * buffer management */
+ break;
+ case CHAN_SOCKDATA:
+ pfd_unthrottle(c->u.pfd.s);
+ break;
+ }
+ }
+}
+
/*
- * Potentially enlarge the window on an SSH2 channel.
+ * Potentially enlarge the window on an SSH-2 channel.
*/
static void ssh2_set_window(struct ssh_channel *c, unsigned newwin)
{
if (c->closes != 0)
return;
- if (newwin > c->v.v2.locwindow) {
+ /*
+ * Only send a WINDOW_ADJUST if there's significantly more window
+ * available than the other end thinks there is. This saves us
+ * sending a WINDOW_ADJUST for every character in a shell session.
+ *
+ * "Significant" is arbitrarily defined as half the window size.
+ */
+ if (newwin > c->v.v2.locwindow * 2) {
struct Packet *pktout;
pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
unsigned i = ssh_pkt_getuint32(pktin);
struct ssh_channel *c;
c = find234(ssh->channels, &i, ssh_channelfind);
- if (c && !c->closes)
+ if (c && !c->closes) {
c->v.v2.remwindow += ssh_pkt_getuint32(pktin);
+ ssh2_try_send_and_unthrottle(c);
+ }
}
static void ssh2_msg_channel_data(Ssh ssh, struct Packet *pktin)
case CHAN_AGENT:
while (length > 0) {
if (c->u.a.lensofar < 4) {
- int l = min(4 - c->u.a.lensofar, length);
+ unsigned int l = min(4 - c->u.a.lensofar, length);
memcpy(c->u.a.msglen + c->u.a.lensofar,
data, l);
data += l;
memcpy(c->u.a.message, c->u.a.msglen, 4);
}
if (c->u.a.lensofar >= 4 && length > 0) {
- int l =
+ unsigned int l =
min(c->u.a.totallen - c->u.a.lensofar,
length);
memcpy(c->u.a.message + c->u.a.lensofar,
struct Packet *pktout;
c = find234(ssh->channels, &i, ssh_channelfind);
- if (!c || ((int)c->remoteid) == -1) {
+ if (!c || c->halfopen) {
bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
c ? "half-open" : "nonexistent", i));
return;
* not running in -N mode.)
*/
if (!ssh->cfg.ssh_no_shell && count234(ssh->channels) == 0) {
- logevent("All channels closed. Disconnecting");
-#if 0
/*
* We used to send SSH_MSG_DISCONNECT here,
* because I'd believed that _every_ conforming
- * SSH2 connection had to end with a disconnect
+ * SSH-2 connection had to end with a disconnect
* being sent by at least one side; apparently
* I was wrong and it's perfectly OK to
* unceremoniously slam the connection shut
* this is more polite than sending a
* DISCONNECT. So now we don't.
*/
- s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
- ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
- ssh2_pkt_addstring(s->pktout, "All open channels closed");
- ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
- ssh2_pkt_send_noqueue(ssh, s->pktout);
-#endif
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ ssh_disconnect(ssh, "All channels closed", NULL, 0, TRUE);
}
}
if (c->type != CHAN_SOCKDATA_DORMANT)
return; /* dunno why they're confirming this */
c->remoteid = ssh_pkt_getuint32(pktin);
+ c->halfopen = FALSE;
c->type = CHAN_SOCKDATA;
c->v.v2.remwindow = ssh_pkt_getuint32(pktin);
c->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
unsigned reason_code;
char *reason_string;
int reason_length;
- char *message;
struct ssh_channel *c;
c = find234(ssh->channels, &i, ssh_channelfind);
if (!c)
if (reason_code >= lenof(reasons))
reason_code = 0; /* ensure reasons[reason_code] in range */
ssh_pkt_getstring(pktin, &reason_string, &reason_length);
- message = dupprintf("Forwarded connection refused by"
- " server: %s [%.*s]", reasons[reason_code],
- reason_length, reason_string);
- logevent(message);
- sfree(message);
+ logeventf(ssh, "Forwarded connection refused by server: %s [%.*s]",
+ reasons[reason_code], reason_length, reason_string);
pfd_close(c->u.pfd.s);
*/
c = find234(ssh->channels, &localid, ssh_channelfind);
if (!c) {
- char buf[80];
- sprintf(buf, "Received channel request for nonexistent"
- " channel %d", localid);
- logevent(buf);
- pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
- ssh2_pkt_adduint32(pktout, SSH2_DISCONNECT_BY_APPLICATION);
- ssh2_pkt_addstring(pktout, buf);
- ssh2_pkt_addstring(pktout, "en"); /* language tag */
- ssh2_pkt_send_noqueue(ssh, pktout);
- connection_fatal(ssh->frontend, "%s", buf);
- ssh_closing((Plug)ssh, NULL, 0, 0);
+ char *buf = dupprintf("Received channel request for nonexistent"
+ " channel %d", localid);
+ ssh_disconnect(ssh, NULL, buf, SSH2_DISCONNECT_PROTOCOL_ERROR, FALSE);
+ sfree(buf);
return;
}
if (q >= 0 && q+4 <= len) { \
q = q + 4 + GET_32BIT(p+q); \
if (q >= 0 && q+4 <= len && \
- (q = q + 4 + GET_32BIT(p+q)) && q == len) \
+ ((q = q + 4 + GET_32BIT(p+q))!= 0) && q == len) \
result = TRUE; \
} \
} while(0)
const char *e = pfd_newconnect(&c->u.pfd.s,
realpf->dhost,
realpf->dport, c,
- &ssh->cfg);
+ &ssh->cfg,
+ realpf->pfrec->addressfamily);
logeventf(ssh, "Attempting to forward remote port to "
"%s:%d", realpf->dhost, realpf->dport);
if (e != NULL) {
}
}
} else if (typelen == 22 &&
- !memcmp(type, "auth-agent@openssh.com", 3)) {
+ !memcmp(type, "auth-agent@openssh.com", 22)) {
if (!ssh->agentfwd_enabled)
error = "Agent forwarding is not enabled";
else {
}
c->remoteid = remid;
+ c->halfopen = FALSE;
if (error) {
pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE);
ssh2_pkt_adduint32(pktout, c->remoteid);
ssh2_pkt_adduint32(pktout, c->remoteid);
ssh2_pkt_adduint32(pktout, c->localid);
ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);
- ssh2_pkt_adduint32(pktout, 0x4000UL); /* our max pkt size */
+ ssh2_pkt_adduint32(pktout, OUR_V2_MAXPKT); /* our max pkt size */
ssh2_pkt_send(ssh, pktout);
}
}
/*
- * Handle the SSH2 userauth and connection layers.
+ * Buffer banner messages for later display at some convenient point.
+ */
+static void ssh2_msg_userauth_banner(Ssh ssh, struct Packet *pktin)
+{
+ /* Arbitrary limit to prevent unbounded inflation of buffer */
+ if (bufchain_size(&ssh->banner) <= 131072) {
+ char *banner = NULL;
+ int size = 0;
+ ssh_pkt_getstring(pktin, &banner, &size);
+ if (banner)
+ bufchain_add(&ssh->banner, banner, size);
+ }
+}
+
+/* Helper function to deal with sending tty modes for "pty-req" */
+static void ssh2_send_ttymode(void *data, char *mode, char *val)
+{
+ struct Packet *pktout = (struct Packet *)data;
+ int i = 0;
+ unsigned int arg = 0;
+ while (strcmp(mode, ssh_ttymodes[i].mode) != 0) i++;
+ if (i == lenof(ssh_ttymodes)) return;
+ switch (ssh_ttymodes[i].type) {
+ case TTY_OP_CHAR:
+ arg = ssh_tty_parse_specchar(val);
+ break;
+ case TTY_OP_BOOL:
+ arg = ssh_tty_parse_boolean(val);
+ break;
+ }
+ ssh2_pkt_addbyte(pktout, ssh_ttymodes[i].opcode);
+ ssh2_pkt_adduint32(pktout, arg);
+}
+
+/*
+ * Handle the SSH-2 userauth and connection layers.
*/
static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
struct Packet *pktin)
AUTH_TYPE_KEYBOARD_INTERACTIVE,
AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
} type;
+ int done_service_req;
int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
- int tried_pubkey_config, tried_agent, tried_keyb_inter;
- int kbd_inter_running;
+ int tried_pubkey_config, tried_agent;
+ int kbd_inter_refused;
int we_are_in;
- int num_prompts, curr_prompt, echo;
+ prompts_t *cur_prompt;
+ int num_prompts;
char username[100];
int got_username;
- char pwprompt[512];
- char password[100];
void *publickey_blob;
int publickey_bloblen;
+ int publickey_encrypted;
+ char *publickey_algorithm;
+ char *publickey_comment;
unsigned char request[5], *response, *p;
int responselen;
int keyi, nkeys;
crBegin(ssh->do_ssh2_authconn_crstate);
+ s->done_service_req = FALSE;
+ s->we_are_in = FALSE;
+ if (!ssh->cfg.ssh_no_userauth) {
+ /*
+ * Request userauth protocol, and await a response to it.
+ */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
+ ssh2_pkt_addstring(s->pktout, "ssh-userauth");
+ ssh2_pkt_send(ssh, s->pktout);
+ crWaitUntilV(pktin);
+ if (pktin->type == SSH2_MSG_SERVICE_ACCEPT)
+ s->done_service_req = TRUE;
+ }
+ if (!s->done_service_req) {
+ /*
+ * Request connection protocol directly, without authentication.
+ */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
+ ssh2_pkt_addstring(s->pktout, "ssh-connection");
+ ssh2_pkt_send(ssh, s->pktout);
+ crWaitUntilV(pktin);
+ if (pktin->type == SSH2_MSG_SERVICE_ACCEPT) {
+ s->we_are_in = TRUE; /* no auth required */
+ } else {
+ bombout(("Server refused service request"));
+ crStopV;
+ }
+ }
+
/*
- * Request userauth protocol, and await a response to it.
+ * Misc one-time setup for authentication.
*/
- s->pktout = ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
- ssh2_pkt_addstring(s->pktout, "ssh-userauth");
- ssh2_pkt_send(ssh, s->pktout);
- crWaitUntilV(pktin);
- if (pktin->type != SSH2_MSG_SERVICE_ACCEPT) {
- bombout(("Server refused user authentication protocol"));
- crStopV;
+ s->publickey_blob = NULL;
+ if (!s->we_are_in) {
+
+ /*
+ * Load the public half of any configured public key file
+ * for later use.
+ */
+ if (!filename_is_null(ssh->cfg.keyfile)) {
+ int keytype;
+ logeventf(ssh, "Reading private key file \"%.150s\"",
+ filename_to_str(&ssh->cfg.keyfile));
+ keytype = key_type(&ssh->cfg.keyfile);
+ if (keytype == SSH_KEYTYPE_SSH2) {
+ const char *error;
+ s->publickey_blob =
+ ssh2_userkey_loadpub(&ssh->cfg.keyfile,
+ &s->publickey_algorithm,
+ &s->publickey_bloblen,
+ &s->publickey_comment, &error);
+ if (s->publickey_blob) {
+ s->publickey_encrypted =
+ ssh2_userkey_encrypted(&ssh->cfg.keyfile, NULL);
+ } else {
+ char *msgbuf;
+ logeventf(ssh, "Unable to load private key (%s)",
+ error);
+ msgbuf = dupprintf("Unable to load private key file "
+ "\"%.150s\" (%s)\r\n",
+ filename_to_str(&ssh->cfg.keyfile),
+ error);
+ c_write_str(ssh, msgbuf);
+ sfree(msgbuf);
+ }
+ } else {
+ char *msgbuf;
+ logeventf(ssh, "Unable to use this key file (%s)",
+ key_type_to_str(keytype));
+ msgbuf = dupprintf("Unable to use key file \"%.150s\""
+ " (%s)\r\n",
+ filename_to_str(&ssh->cfg.keyfile),
+ key_type_to_str(keytype));
+ c_write_str(ssh, msgbuf);
+ sfree(msgbuf);
+ s->publickey_blob = NULL;
+ }
+ }
+
}
/*
*/
s->username[0] = '\0';
s->got_username = FALSE;
- do {
+ bufchain_init(&ssh->banner);
+ ssh->packet_dispatch[SSH2_MSG_USERAUTH_BANNER] =
+ ssh2_msg_userauth_banner;
+ while (!s->we_are_in) {
/*
* Get a username.
*/
* it again.
*/
} else if (!*ssh->cfg.username) {
- if (ssh_get_line && !ssh_getline_pw_only) {
- if (!ssh_get_line("login as: ",
- s->username, sizeof(s->username), FALSE)) {
- /*
- * get_line failed to get a username.
- * Terminate.
- */
- logevent("No username provided. Abandoning session.");
- ssh_closing((Plug)ssh, NULL, 0, 0);
- crStopV;
- }
- } else {
- int ret; /* need not be saved across crReturn */
- c_write_str(ssh, "login as: ");
+ int ret; /* need not be kept over crReturn */
+ s->cur_prompt = new_prompts(ssh->frontend);
+ s->cur_prompt->to_server = TRUE;
+ s->cur_prompt->name = dupstr("SSH login name");
+ add_prompt(s->cur_prompt, dupstr("login as: "), TRUE,
+ lenof(s->username));
+ ret = get_userpass_input(s->cur_prompt, NULL, 0);
+ while (ret < 0) {
ssh->send_ok = 1;
- setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
- do {
- crWaitUntilV(!pktin);
- ret = process_userpass_input(ssh, in, inlen);
- } while (ret == 0);
- if (ret < 0)
- cleanup_exit(0);
- c_write_str(ssh, "\r\n");
+ crWaitUntilV(!pktin);
+ ret = get_userpass_input(s->cur_prompt, in, inlen);
+ ssh->send_ok = 0;
}
- s->username[strcspn(s->username, "\n\r")] = '\0';
+ if (!ret) {
+ /*
+ * get_userpass_input() failed to get a username.
+ * Terminate.
+ */
+ free_prompts(s->cur_prompt);
+ ssh_disconnect(ssh, "No username provided", NULL, 0, TRUE);
+ crStopV;
+ }
+ memcpy(s->username, s->cur_prompt->prompts[0]->result,
+ lenof(s->username));
+ free_prompts(s->cur_prompt);
} else {
char *stuff;
strncpy(s->username, ssh->cfg.username, sizeof(s->username));
s->tried_pubkey_config = FALSE;
s->tried_agent = FALSE;
- s->tried_keyb_inter = FALSE;
- s->kbd_inter_running = FALSE;
- /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
- if (!filename_is_null(ssh->cfg.keyfile)) {
- int keytype;
- logeventf(ssh, "Reading private key file \"%.150s\"",
- filename_to_str(&ssh->cfg.keyfile));
- keytype = key_type(&ssh->cfg.keyfile);
- if (keytype == SSH_KEYTYPE_SSH2) {
- s->publickey_blob =
- ssh2_userkey_loadpub(&ssh->cfg.keyfile, NULL,
- &s->publickey_bloblen, NULL);
- } else {
- char *msgbuf;
- logeventf(ssh, "Unable to use this key file (%s)",
- key_type_to_str(keytype));
- msgbuf = dupprintf("Unable to use key file \"%.150s\""
- " (%s)\r\n",
- filename_to_str(&ssh->cfg.keyfile),
- key_type_to_str(keytype));
- c_write_str(ssh, msgbuf);
- sfree(msgbuf);
- s->publickey_blob = NULL;
- }
- } else
- s->publickey_blob = NULL;
+ s->kbd_inter_refused = FALSE;
while (1) {
/*
*/
if (!s->gotit)
crWaitUntilV(pktin);
- while (pktin->type == SSH2_MSG_USERAUTH_BANNER) {
- char *banner;
- int size;
+ /*
+ * Now is a convenient point to spew any banner material
+ * that we've accumulated. (This should ensure that when
+ * we exit the auth loop, we haven't any left to deal
+ * with.)
+ */
+ {
+ int size = bufchain_size(&ssh->banner);
/*
* Don't show the banner if we're operating in
* non-verbose non-interactive mode. (It's probably
* the banner will screw up processing on the
* output of (say) plink.)
*/
- if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) {
- ssh_pkt_getstring(pktin, &banner, &size);
- if (banner)
- c_write_untrusted(ssh, banner, size);
+ if (size && (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE))) {
+ char *banner = snewn(size, char);
+ bufchain_fetch(&ssh->banner, banner, size);
+ c_write_untrusted(ssh, banner, size);
+ sfree(banner);
}
- crWaitUntilV(pktin);
+ bufchain_clear(&ssh->banner);
}
if (pktin->type == SSH2_MSG_USERAUTH_SUCCESS) {
logevent("Access granted");
break;
}
- if (s->kbd_inter_running &&
- pktin->type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
- /*
- * This is either a further set-of-prompts packet
- * in keyboard-interactive authentication, or it's
- * the same one and we came back here with `gotit'
- * set. In the former case, we must reset the
- * curr_prompt variable.
- */
- if (!s->gotit)
- s->curr_prompt = 0;
+ if (pktin->type == SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ) {
+ /* FIXME: perhaps we should support this? */
+ bombout(("PASSWD_CHANGEREQ not yet supported"));
+ crStopV;
} else if (pktin->type != SSH2_MSG_USERAUTH_FAILURE) {
bombout(("Strange packet received during authentication: type %d",
pktin->type));
char *methods;
int methlen;
ssh_pkt_getstring(pktin, &methods, &methlen);
- s->kbd_inter_running = FALSE;
if (!ssh2_pkt_getbool(pktin)) {
/*
* We have received an unequivocal Access
in_commasep_string("keyboard-interactive", methods, methlen);
}
- s->method = 0;
ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
- s->need_pw = FALSE;
- /*
- * Most password/passphrase prompts will be
- * non-echoing, so we set this to 0 by default.
- * Exception is that some keyboard-interactive prompts
- * can be echoing, in which case we'll set this to 1.
- */
- s->echo = 0;
+ if (s->can_pubkey && agent_exists() && !s->tried_agent) {
- if (!s->method && s->can_pubkey &&
- agent_exists() && !s->tried_agent) {
/*
* Attempt public-key authentication using Pageant.
*/
s->p = s->response + 5;
s->nkeys = GET_32BIT(s->p);
s->p += 4;
- {
- char buf[64];
- sprintf(buf, "Pageant has %d SSH2 keys", s->nkeys);
- logevent(buf);
- }
+ logeventf(ssh, "Pageant has %d SSH-2 keys", s->nkeys);
for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
void *vret;
- {
- char buf[64];
- sprintf(buf, "Trying Pageant key #%d", s->keyi);
- logevent(buf);
- }
+ logeventf(ssh, "Trying Pageant key #%d", s->keyi);
s->pklen = GET_32BIT(s->p);
s->p += 4;
if (s->publickey_blob &&
ssh2_pkt_addstring_start(s->pktout);
ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
- s->siglen = s->pktout->length - 5 + 4 + 20;
+ s->siglen = s->pktout->length - 5 + 4 +
+ ssh->v2_session_id_len;
if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
s->siglen -= 4;
s->len = 1; /* message type */
s->q += 4;
/* Now the data to be signed... */
if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
- PUT_32BIT(s->q, 20);
+ PUT_32BIT(s->q, ssh->v2_session_id_len);
s->q += 4;
}
- memcpy(s->q, ssh->v2_session_id, 20);
- s->q += 20;
+ memcpy(s->q, ssh->v2_session_id,
+ ssh->v2_session_id_len);
+ s->q += ssh->v2_session_id_len;
memcpy(s->q, s->pktout->data + 5,
s->pktout->length - 5);
s->q += s->pktout->length - 5;
continue;
}
sfree(s->response);
- }
- if (!s->method && s->can_pubkey && s->publickey_blob
- && !s->tried_pubkey_config) {
- unsigned char *pub_blob;
- char *algorithm, *comment;
- int pub_blob_len;
+ } else if (s->can_pubkey && s->publickey_blob &&
+ !s->tried_pubkey_config) {
- s->tried_pubkey_config = TRUE;
+ struct ssh2_userkey *key; /* not live over crReturn */
+ char *passphrase; /* not live over crReturn */
ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
+ s->tried_pubkey_config = TRUE;
+
/*
* Try the public key supplied in the configuration.
*
* First, offer the public blob to see if the server is
* willing to accept it.
*/
- pub_blob =
- (unsigned char *)ssh2_userkey_loadpub(&ssh->cfg.keyfile,
- &algorithm,
- &pub_blob_len,
- NULL);
- if (pub_blob) {
- s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
- ssh2_pkt_addstring(s->pktout, s->username);
- ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
- ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
- ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
- ssh2_pkt_addstring(s->pktout, algorithm);
- ssh2_pkt_addstring_start(s->pktout);
- ssh2_pkt_addstring_data(s->pktout, (char *)pub_blob,
- pub_blob_len);
- ssh2_pkt_send(ssh, s->pktout);
- logevent("Offered public key");
-
- crWaitUntilV(pktin);
- if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
- s->gotit = TRUE;
- s->type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
- continue; /* key refused; give up on it */
- }
-
- logevent("Offer of public key accepted");
- /*
- * Actually attempt a serious authentication using
- * the key.
- */
- if (ssh2_userkey_encrypted(&ssh->cfg.keyfile, &comment)) {
- sprintf(s->pwprompt,
- "Passphrase for key \"%.100s\": ",
- comment);
- s->need_pw = TRUE;
- } else {
- s->need_pw = FALSE;
- }
- if (flags & FLAG_VERBOSE) {
- c_write_str(ssh, "Authenticating with public key \"");
- c_write_str(ssh, comment);
- c_write_str(ssh, "\"\r\n");
- }
- s->method = AUTH_PUBLICKEY_FILE;
- }
- }
-
- if (!s->method && s->can_keyb_inter && !s->tried_keyb_inter) {
- s->method = AUTH_KEYBOARD_INTERACTIVE;
- s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
- s->tried_keyb_inter = TRUE;
-
- ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
- ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
-
s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
ssh2_pkt_addstring(s->pktout, s->username);
- ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
- ssh2_pkt_addstring(s->pktout, "keyboard-interactive"); /* method */
- ssh2_pkt_addstring(s->pktout, ""); /* lang */
- ssh2_pkt_addstring(s->pktout, "");
+ ssh2_pkt_addstring(s->pktout, "ssh-connection");
+ /* service requested */
+ ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
+ ssh2_pkt_addbool(s->pktout, FALSE);
+ /* no signature included */
+ ssh2_pkt_addstring(s->pktout, s->publickey_algorithm);
+ ssh2_pkt_addstring_start(s->pktout);
+ ssh2_pkt_addstring_data(s->pktout,
+ (char *)s->publickey_blob,
+ s->publickey_bloblen);
ssh2_pkt_send(ssh, s->pktout);
+ logevent("Offered public key");
crWaitUntilV(pktin);
- if (pktin->type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
- if (pktin->type == SSH2_MSG_USERAUTH_FAILURE)
- s->gotit = TRUE;
- logevent("Keyboard-interactive authentication refused");
- s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
- continue;
- }
-
- s->kbd_inter_running = TRUE;
- s->curr_prompt = 0;
- }
-
- if (s->kbd_inter_running) {
- s->method = AUTH_KEYBOARD_INTERACTIVE;
- s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
- s->tried_keyb_inter = TRUE;
-
- ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
- ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
-
- if (s->curr_prompt == 0) {
- /*
- * We've got a fresh USERAUTH_INFO_REQUEST.
- * Display header data, and start going through
- * the prompts.
- */
- char *name, *inst, *lang;
- int name_len, inst_len, lang_len;
-
- ssh_pkt_getstring(pktin, &name, &name_len);
- ssh_pkt_getstring(pktin, &inst, &inst_len);
- ssh_pkt_getstring(pktin, &lang, &lang_len);
- if (name_len > 0) {
- c_write_untrusted(ssh, name, name_len);
- c_write_str(ssh, "\r\n");
- }
- if (inst_len > 0) {
- c_write_untrusted(ssh, inst, inst_len);
- c_write_str(ssh, "\r\n");
- }
- s->num_prompts = ssh_pkt_getuint32(pktin);
+ if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
+ /* Key refused. Give up. */
+ s->gotit = TRUE; /* reconsider message next loop */
+ s->type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
+ continue; /* process this new message */
}
+ s->method = AUTH_PUBLICKEY_FILE;
+ logevent("Offer of public key accepted");
/*
- * If there are prompts remaining in the packet,
- * display one and get a response.
+ * Actually attempt a serious authentication using
+ * the key.
*/
- if (s->curr_prompt < s->num_prompts) {
- char *prompt;
- int prompt_len;
-
- ssh_pkt_getstring(pktin, &prompt, &prompt_len);
- if (prompt_len > 0) {
- static const char trunc[] = "<prompt truncated>: ";
- static const int prlen = sizeof(s->pwprompt) -
- lenof(trunc);
- if (prompt_len > prlen) {
- memcpy(s->pwprompt, prompt, prlen);
- strcpy(s->pwprompt + prlen, trunc);
- } else {
- memcpy(s->pwprompt, prompt, prompt_len);
- s->pwprompt[prompt_len] = '\0';
+ if (flags & FLAG_VERBOSE) {
+ c_write_str(ssh, "Authenticating with public key \"");
+ c_write_str(ssh, s->publickey_comment);
+ c_write_str(ssh, "\"\r\n");
+ }
+ key = NULL;
+ while (!key) {
+ const char *error; /* not live over crReturn */
+ if (s->publickey_encrypted) {
+ /*
+ * Get a passphrase from the user.
+ */
+ int ret; /* need not be kept over crReturn */
+ s->cur_prompt = new_prompts(ssh->frontend);
+ s->cur_prompt->to_server = FALSE;
+ s->cur_prompt->name = dupstr("SSH key passphrase");
+ add_prompt(s->cur_prompt,
+ dupprintf("Passphrase for key \"%.100s\": ",
+ s->publickey_comment),
+ FALSE, SSH_MAX_PASSWORD_LEN);
+ ret = get_userpass_input(s->cur_prompt, NULL, 0);
+ while (ret < 0) {
+ ssh->send_ok = 1;
+ crWaitUntilV(!pktin);
+ ret = get_userpass_input(s->cur_prompt,
+ in, inlen);
+ ssh->send_ok = 0;
+ }
+ if (!ret) {
+ /* Failed to get a passphrase. Terminate. */
+ free_prompts(s->cur_prompt);
+ ssh_disconnect(ssh, NULL,
+ "Unable to authenticate",
+ SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER,
+ TRUE);
+ crStopV;
}
+ passphrase =
+ dupstr(s->cur_prompt->prompts[0]->result);
+ free_prompts(s->cur_prompt);
} else {
- strcpy(s->pwprompt,
- "<server failed to send prompt>: ");
+ passphrase = NULL; /* no passphrase needed */
}
- s->echo = ssh2_pkt_getbool(pktin);
- s->need_pw = TRUE;
- } else
- s->need_pw = FALSE;
- }
-
- if (!s->method && s->can_passwd) {
- s->method = AUTH_PASSWORD;
- ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
- ssh->pkt_ctx |= SSH2_PKTCTX_PASSWORD;
- sprintf(s->pwprompt, "%.90s@%.90s's password: ", s->username,
- ssh->savedhost);
- s->need_pw = TRUE;
- }
- if (s->need_pw) {
- if (ssh_get_line) {
- if (!ssh_get_line(s->pwprompt, s->password,
- sizeof(s->password), TRUE)) {
- /*
- * get_line failed to get a password (for
- * example because one was supplied on the
- * command line which has already failed to
- * work). Terminate.
- */
- s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
- ssh2_pkt_adduint32(s->pktout,SSH2_DISCONNECT_BY_APPLICATION);
- ssh2_pkt_addstring(s->pktout, "No more passwords available"
- " to try");
- ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
- ssh2_pkt_send_noqueue(ssh, s->pktout);
- logevent("Unable to authenticate");
- connection_fatal(ssh->frontend,
- "Unable to authenticate");
- ssh_closing((Plug)ssh, NULL, 0, 0);
- crStopV;
+ /*
+ * Try decrypting the key.
+ */
+ key = ssh2_load_userkey(&ssh->cfg.keyfile, passphrase,
+ &error);
+ if (passphrase) {
+ /* burn the evidence */
+ memset(passphrase, 0, strlen(passphrase));
+ sfree(passphrase);
+ }
+ if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
+ if (passphrase &&
+ (key == SSH2_WRONG_PASSPHRASE)) {
+ c_write_str(ssh, "Wrong passphrase\r\n");
+ key = NULL;
+ /* and loop again */
+ } else {
+ c_write_str(ssh, "Unable to load private key (");
+ c_write_str(ssh, error);
+ c_write_str(ssh, ")\r\n");
+ key = NULL;
+ break; /* try something else */
+ }
}
- } else {
- int ret; /* need not be saved across crReturn */
- c_write_untrusted(ssh, s->pwprompt, strlen(s->pwprompt));
- ssh->send_ok = 1;
-
- setup_userpass_input(ssh, s->password,
- sizeof(s->password), s->echo);
- do {
- crWaitUntilV(!pktin);
- ret = process_userpass_input(ssh, in, inlen);
- } while (ret == 0);
- if (ret < 0)
- cleanup_exit(0);
- c_write_str(ssh, "\r\n");
}
- }
- if (s->method == AUTH_PUBLICKEY_FILE) {
- /*
- * We have our passphrase. Now try the actual authentication.
- */
- struct ssh2_userkey *key;
- const char *error = NULL;
-
- key = ssh2_load_userkey(&ssh->cfg.keyfile, s->password,
- &error);
- if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
- if (key == SSH2_WRONG_PASSPHRASE) {
- c_write_str(ssh, "Wrong passphrase\r\n");
- s->tried_pubkey_config = FALSE;
- } else {
- c_write_str(ssh, "Unable to load private key (");
- c_write_str(ssh, error);
- c_write_str(ssh, ")\r\n");
- s->tried_pubkey_config = TRUE;
- }
- /* Send a spurious AUTH_NONE to return to the top. */
- s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
- ssh2_pkt_addstring(s->pktout, s->username);
- ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
- ssh2_pkt_addstring(s->pktout, "none"); /* method */
- ssh2_pkt_send(ssh, s->pktout);
- s->type = AUTH_TYPE_NONE;
- } else {
+ if (key) {
unsigned char *pkblob, *sigblob, *sigdata;
int pkblob_len, sigblob_len, sigdata_len;
- int p;
+ int p;
/*
* We have loaded the private key and the server
*/
s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
ssh2_pkt_addstring(s->pktout, s->username);
- ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
- ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
+ ssh2_pkt_addstring(s->pktout, "ssh-connection");
+ /* service requested */
+ ssh2_pkt_addstring(s->pktout, "publickey");
+ /* method */
ssh2_pkt_addbool(s->pktout, TRUE);
+ /* signature follows */
ssh2_pkt_addstring(s->pktout, key->alg->name);
- pkblob = key->alg->public_blob(key->data, &pkblob_len);
+ pkblob = key->alg->public_blob(key->data,
+ &pkblob_len);
ssh2_pkt_addstring_start(s->pktout);
- ssh2_pkt_addstring_data(s->pktout, (char *)pkblob, pkblob_len);
+ ssh2_pkt_addstring_data(s->pktout, (char *)pkblob,
+ pkblob_len);
/*
* The data to be signed is:
* followed by everything so far placed in the
* outgoing packet.
*/
- sigdata_len = s->pktout->length - 5 + 4 + 20;
- if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
- sigdata_len -= 4;
+ sigdata_len = s->pktout->length - 5 + 4 +
+ ssh->v2_session_id_len;
+ if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
+ sigdata_len -= 4;
sigdata = snewn(sigdata_len, unsigned char);
- p = 0;
- if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
- PUT_32BIT(sigdata+p, 20);
- p += 4;
- }
- memcpy(sigdata+p, ssh->v2_session_id, 20); p += 20;
+ p = 0;
+ if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
+ PUT_32BIT(sigdata+p, ssh->v2_session_id_len);
+ p += 4;
+ }
+ memcpy(sigdata+p, ssh->v2_session_id,
+ ssh->v2_session_id_len);
+ p += ssh->v2_session_id_len;
memcpy(sigdata+p, s->pktout->data + 5,
s->pktout->length - 5);
- p += s->pktout->length - 5;
- assert(p == sigdata_len);
+ p += s->pktout->length - 5;
+ assert(p == sigdata_len);
sigblob = key->alg->sign(key->data, (char *)sigdata,
sigdata_len, &sigblob_len);
ssh2_add_sigblob(ssh, s->pktout, pkblob, pkblob_len,
s->type = AUTH_TYPE_PUBLICKEY;
key->alg->freekey(key->data);
}
- } else if (s->method == AUTH_PASSWORD) {
+
+ } else if (s->can_keyb_inter && !s->kbd_inter_refused) {
+
/*
- * We send the password packet lumped tightly together with
- * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
- * string long enough to make the total length of the two
- * packets constant. This should ensure that a passive
- * listener doing traffic analyis can't work out the length
- * of the password.
- *
- * For this to work, we need an assumption about the
- * maximum length of the password packet. I think 256 is
- * pretty conservative. Anyone using a password longer than
- * that probably doesn't have much to worry about from
- * people who find out how long their password is!
+ * Keyboard-interactive authentication.
*/
+ char *name, *inst, *lang;
+ int name_len, inst_len, lang_len;
+ int i;
+
+ s->method = AUTH_KEYBOARD_INTERACTIVE;
+ s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
+
+ ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
+ ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
+
s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
ssh2_pkt_addstring(s->pktout, s->username);
- ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
- ssh2_pkt_addstring(s->pktout, "password");
- ssh2_pkt_addbool(s->pktout, FALSE);
- dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
- ssh2_pkt_addstring(s->pktout, s->password);
- memset(s->password, 0, sizeof(s->password));
- end_log_omission(ssh, s->pktout);
- ssh2_pkt_defer(ssh, s->pktout);
+ ssh2_pkt_addstring(s->pktout, "ssh-connection");
+ /* service requested */
+ ssh2_pkt_addstring(s->pktout, "keyboard-interactive");
+ /* method */
+ ssh2_pkt_addstring(s->pktout, ""); /* lang */
+ ssh2_pkt_addstring(s->pktout, ""); /* submethods */
+ ssh2_pkt_send(ssh, s->pktout);
+
+ crWaitUntilV(pktin);
+ if (pktin->type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
+ /* Server is not willing to do keyboard-interactive
+ * at all. Give up on it entirely. */
+ s->gotit = TRUE;
+ if (pktin->type == SSH2_MSG_USERAUTH_FAILURE)
+ logevent("Keyboard-interactive authentication refused");
+ s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
+ s->kbd_inter_refused = TRUE; /* don't try it again */
+ continue;
+ }
+
+ /*
+ * We've got a fresh USERAUTH_INFO_REQUEST.
+ * Get the preamble and start building a prompt.
+ */
+ ssh_pkt_getstring(pktin, &name, &name_len);
+ ssh_pkt_getstring(pktin, &inst, &inst_len);
+ ssh_pkt_getstring(pktin, &lang, &lang_len);
+ s->cur_prompt = new_prompts(ssh->frontend);
+ s->cur_prompt->to_server = TRUE;
+ if (name_len) {
+ /* FIXME: better prefix to distinguish from
+ * local prompts? */
+ s->cur_prompt->name = dupprintf("SSH server: %.*s",
+ name_len, name);
+ s->cur_prompt->name_reqd = TRUE;
+ } else {
+ s->cur_prompt->name = dupstr("SSH server authentication");
+ s->cur_prompt->name_reqd = FALSE;
+ }
+ s->cur_prompt->instruction =
+ dupprintf("Using keyboard-interactive authentication.%s%.*s",
+ inst_len ? "\n" : "", inst_len, inst);
+ s->cur_prompt->instr_reqd = TRUE;
+
/*
- * We'll include a string that's an exact multiple of the
- * cipher block size. If the cipher is NULL for some
- * reason, we don't do this trick at all because we gain
- * nothing by it.
+ * Get the prompts from the packet.
*/
- if (ssh->cscipher) {
- int stringlen, i;
+ s->num_prompts = ssh_pkt_getuint32(pktin);
+ for (i = 0; i < s->num_prompts; i++) {
+ char *prompt;
+ int prompt_len;
+ int echo;
+ static char noprompt[] =
+ "<server failed to send prompt>: ";
+
+ ssh_pkt_getstring(pktin, &prompt, &prompt_len);
+ echo = ssh2_pkt_getbool(pktin);
+ if (!prompt_len) {
+ prompt = noprompt;
+ prompt_len = lenof(noprompt)-1;
+ }
+ add_prompt(s->cur_prompt,
+ dupprintf("%.*s", prompt_len, prompt),
+ echo, SSH_MAX_PASSWORD_LEN);
+ }
- stringlen = (256 - ssh->deferred_len);
- stringlen += ssh->cscipher->blksize - 1;
- stringlen -= (stringlen % ssh->cscipher->blksize);
- if (ssh->cscomp) {
+ /*
+ * Get the user's responses.
+ */
+ if (s->num_prompts) {
+ int ret; /* not live over crReturn */
+ ret = get_userpass_input(s->cur_prompt, NULL, 0);
+ while (ret < 0) {
+ ssh->send_ok = 1;
+ crWaitUntilV(!pktin);
+ ret = get_userpass_input(s->cur_prompt, in, inlen);
+ ssh->send_ok = 0;
+ }
+ if (!ret) {
/*
- * Temporarily disable actual compression,
- * so we can guarantee to get this string
- * exactly the length we want it. The
- * compression-disabling routine should
- * return an integer indicating how many
- * bytes we should adjust our string length
- * by.
+ * Failed to get responses. Terminate.
*/
- stringlen -=
- ssh->cscomp->disable_compression(ssh->cs_comp_ctx);
- }
- s->pktout = ssh2_pkt_init(SSH2_MSG_IGNORE);
- ssh2_pkt_addstring_start(s->pktout);
- for (i = 0; i < stringlen; i++) {
- char c = (char) random_byte();
- ssh2_pkt_addstring_data(s->pktout, &c, 1);
+ free_prompts(s->cur_prompt);
+ ssh_disconnect(ssh, NULL, "Unable to authenticate",
+ SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER,
+ TRUE);
+ crStopV;
}
- ssh2_pkt_defer(ssh, s->pktout);
- }
- ssh_pkt_defersend(ssh);
- logevent("Sent password");
- s->type = AUTH_TYPE_PASSWORD;
- } else if (s->method == AUTH_KEYBOARD_INTERACTIVE) {
- if (s->curr_prompt == 0) {
- s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE);
- ssh2_pkt_adduint32(s->pktout, s->num_prompts);
}
- if (s->need_pw) { /* only add pw if we just got one! */
+
+ /*
+ * Send the responses to the server.
+ */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE);
+ s->pktout->forcepad = 256;
+ ssh2_pkt_adduint32(s->pktout, s->num_prompts);
+ for (i=0; i < s->num_prompts; i++) {
dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
- ssh2_pkt_addstring(s->pktout, s->password);
- memset(s->password, 0, sizeof(s->password));
+ ssh2_pkt_addstring(s->pktout,
+ s->cur_prompt->prompts[i]->result);
end_log_omission(ssh, s->pktout);
- s->curr_prompt++;
}
- if (s->curr_prompt >= s->num_prompts) {
- ssh2_pkt_send(ssh, s->pktout);
- } else {
+ ssh2_pkt_send(ssh, s->pktout);
+ s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE; /*FIXME?*/
+
+ } else if (s->can_passwd) {
+
+ /*
+ * Plain old password authentication.
+ */
+ int ret; /* not live over crReturn */
+
+ s->method = AUTH_PASSWORD;
+ ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
+ ssh->pkt_ctx |= SSH2_PKTCTX_PASSWORD;
+
+ s->cur_prompt = new_prompts(ssh->frontend);
+ s->cur_prompt->to_server = TRUE;
+ s->cur_prompt->name = dupstr("SSH password");
+ add_prompt(s->cur_prompt, dupprintf("%.90s@%.90s's password: ",
+ s->username,
+ ssh->savedhost),
+ FALSE, SSH_MAX_PASSWORD_LEN);
+
+ ret = get_userpass_input(s->cur_prompt, NULL, 0);
+ while (ret < 0) {
+ ssh->send_ok = 1;
+ crWaitUntilV(!pktin);
+ ret = get_userpass_input(s->cur_prompt, in, inlen);
+ ssh->send_ok = 0;
+ }
+ if (!ret) {
/*
- * If there are prompts remaining, we set
- * `gotit' so that we won't attempt to get
- * another packet. Then we go back round the
- * loop and will end up retrieving another
- * prompt out of the existing packet. Funky or
- * what?
+ * Failed to get responses. Terminate.
*/
- s->gotit = TRUE;
+ free_prompts(s->cur_prompt);
+ ssh_disconnect(ssh, NULL, "Unable to authenticate",
+ SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER,
+ TRUE);
+ crStopV;
}
- s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
+
+ /*
+ * Send the password packet.
+ *
+ * We pad out the password packet to 256 bytes to make
+ * it harder for an attacker to find the length of the
+ * user's password.
+ *
+ * Anyone using a password longer than 256 bytes
+ * probably doesn't have much to worry about from
+ * people who find out how long their password is!
+ */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
+ s->pktout->forcepad = 256;
+ ssh2_pkt_addstring(s->pktout, s->username);
+ ssh2_pkt_addstring(s->pktout, "ssh-connection");
+ /* service requested */
+ ssh2_pkt_addstring(s->pktout, "password");
+ ssh2_pkt_addbool(s->pktout, FALSE);
+ dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
+ ssh2_pkt_addstring(s->pktout,
+ s->cur_prompt->prompts[0]->result);
+ free_prompts(s->cur_prompt);
+ end_log_omission(ssh, s->pktout);
+ ssh2_pkt_send(ssh, s->pktout);
+ logevent("Sent password");
+ s->type = AUTH_TYPE_PASSWORD; /*FIXME?*/
+
} else {
- c_write_str(ssh, "No supported authentication methods"
- " left to try!\r\n");
- logevent("No supported authentications offered."
- " Disconnecting");
- s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
- ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
- ssh2_pkt_addstring(s->pktout, "No supported authentication"
- " methods available");
- ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
- ssh2_pkt_send_noqueue(ssh, s->pktout);
- ssh_closing((Plug)ssh, NULL, 0, 0);
+
+ ssh_disconnect(ssh, NULL,
+ "No supported authentication methods available",
+ SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE,
+ FALSE);
crStopV;
+
}
+
}
- } while (!s->we_are_in);
+ }
+ ssh->packet_dispatch[SSH2_MSG_USERAUTH_BANNER] = NULL;
+
+ /* Clear up various bits and pieces from authentication. */
+ if (s->publickey_blob) {
+ sfree(s->publickey_blob);
+ sfree(s->publickey_comment);
+ }
/*
- * Now we're authenticated for the connection protocol. The
- * connection protocol will automatically have started at this
- * point; there's no need to send SERVICE_REQUEST.
+ * Now the connection protocol has started, one way or another.
*/
ssh->channels = newtree234(ssh_channelcmp);
ssh2_pkt_adduint32(s->pktout, ssh->mainchan->localid);
ssh->mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
ssh2_pkt_adduint32(s->pktout, ssh->mainchan->v.v2.locwindow);/* our window size */
- ssh2_pkt_adduint32(s->pktout, 0x4000UL); /* our max pkt size */
+ ssh2_pkt_adduint32(s->pktout, OUR_V2_MAXPKT); /* our max pkt size */
ssh2_pkt_send(ssh, s->pktout);
crWaitUntilV(pktin);
if (pktin->type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
crStopV;
}
ssh->mainchan->remoteid = ssh_pkt_getuint32(pktin);
+ ssh->mainchan->halfopen = FALSE;
ssh->mainchan->type = CHAN_MAINSESSION;
ssh->mainchan->closes = 0;
ssh->mainchan->v.v2.remwindow = ssh_pkt_getuint32(pktin);
ssh2_pkt_addbool(s->pktout, 1); /* want reply */
ssh2_pkt_addbool(s->pktout, 0); /* many connections */
ssh2_pkt_addstring(s->pktout, proto);
+ /*
+ * Note that while we blank the X authentication data here, we don't
+ * take any special action to blank the start of an X11 channel,
+ * so using MIT-MAGIC-COOKIE-1 and actually opening an X connection
+ * without having session blanking enabled is likely to leak your
+ * cookie into the log.
+ */
+ dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
ssh2_pkt_addstring(s->pktout, data);
+ end_log_omission(ssh, s->pktout);
ssh2_pkt_adduint32(s->pktout, x11_get_screen_number(ssh->cfg.x11_display));
ssh2_pkt_send(ssh, s->pktout);
/*
* Enable port forwardings.
*/
- {
- char type;
- int n;
- int sport,dport,sserv,dserv;
- char sports[256], dports[256], saddr[256], host[256];
-
- ssh->rportfwds = newtree234(ssh_rportcmp_ssh2);
- /* Add port forwardings. */
- ssh->portfwd_strptr = ssh->cfg.portfwd;
- while (*ssh->portfwd_strptr) {
- type = *ssh->portfwd_strptr++;
- saddr[0] = '\0';
- n = 0;
- while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t') {
- if (*ssh->portfwd_strptr == ':') {
- /*
- * We've seen a colon in the middle of the
- * source port number. This means that
- * everything we've seen until now is the
- * source _address_, so we'll move it into
- * saddr and start sports from the beginning
- * again.
- */
- ssh->portfwd_strptr++;
- sports[n] = '\0';
- strcpy(saddr, sports);
- n = 0;
- }
- if (n < 255) sports[n++] = *ssh->portfwd_strptr++;
- }
- sports[n] = 0;
- if (type != 'D') {
- if (*ssh->portfwd_strptr == '\t')
- ssh->portfwd_strptr++;
- n = 0;
- while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':') {
- if (n < 255) host[n++] = *ssh->portfwd_strptr++;
- }
- host[n] = 0;
- if (*ssh->portfwd_strptr == ':')
- ssh->portfwd_strptr++;
- n = 0;
- while (*ssh->portfwd_strptr) {
- if (n < 255) dports[n++] = *ssh->portfwd_strptr++;
- }
- dports[n] = 0;
- ssh->portfwd_strptr++;
- dport = atoi(dports);
- dserv = 0;
- if (dport == 0) {
- dserv = 1;
- dport = net_service_lookup(dports);
- if (!dport) {
- logeventf(ssh, "Service lookup failed for destination"
- " port \"%s\"", dports);
- }
- }
- } else {
- while (*ssh->portfwd_strptr) ssh->portfwd_strptr++;
- dport = dserv = -1;
- ssh->portfwd_strptr++; /* eat the NUL and move to next one */
- }
- sport = atoi(sports);
- sserv = 0;
- if (sport == 0) {
- sserv = 1;
- sport = net_service_lookup(sports);
- if (!sport) {
- logeventf(ssh, "Service lookup failed for source"
- " port \"%s\"", sports);
- }
- }
- if (sport && dport) {
- /* Set up a description of the source port. */
- static char *sportdesc;
- sportdesc = dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
- (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
- (int)(*saddr?1:0), ":",
- (int)(sserv ? strlen(sports) : 0), sports,
- sserv, "(", sport, sserv, ")");
- if (type == 'L') {
- /* Verbose description of the destination port */
- char *dportdesc = dupprintf("%s:%.*s%.*s%d%.*s",
- host,
- (int)(dserv ? strlen(dports) : 0), dports,
- dserv, "(", dport, dserv, ")");
- const char *err = pfd_addforward(host, dport,
- *saddr ? saddr : NULL,
- sport, ssh, &ssh->cfg);
- if (err) {
- logeventf(ssh, "Local port %s forward to %s"
- " failed: %s", sportdesc, dportdesc, err);
- } else {
- logeventf(ssh, "Local port %s forwarding to %s",
- sportdesc, dportdesc);
- }
- sfree(dportdesc);
- } else if (type == 'D') {
- const char *err = pfd_addforward(NULL, -1,
- *saddr ? saddr : NULL,
- sport, ssh, &ssh->cfg);
- if (err) {
- logeventf(ssh, "Local port %s SOCKS dynamic forward"
- " setup failed: %s", sportdesc, err);
- } else {
- logeventf(ssh, "Local port %s doing SOCKS"
- " dynamic forwarding", sportdesc);
- }
- } else {
- struct ssh_rportfwd *pf;
- pf = snew(struct ssh_rportfwd);
- strcpy(pf->dhost, host);
- pf->dport = dport;
- pf->sport = sport;
- if (add234(ssh->rportfwds, pf) != pf) {
- logeventf(ssh, "Duplicate remote port forwarding"
- " to %s:%d", host, dport);
- sfree(pf);
- } else {
- logeventf(ssh, "Requesting remote port %s"
- " forward to %s:%.*s%.*s%d%.*s",
- sportdesc,
- host,
- (int)(dserv ? strlen(dports) : 0), dports,
- dserv, "(", dport, dserv, ")");
- s->pktout = ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
- ssh2_pkt_addstring(s->pktout, "tcpip-forward");
- ssh2_pkt_addbool(s->pktout, 1);/* want reply */
- if (*saddr) {
- ssh2_pkt_addstring(s->pktout, saddr);
- } else if (ssh->cfg.rport_acceptall) {
- ssh2_pkt_addstring(s->pktout, "0.0.0.0");
- } else {
- ssh2_pkt_addstring(s->pktout, "127.0.0.1");
- }
- ssh2_pkt_adduint32(s->pktout, sport);
- ssh2_pkt_send(ssh, s->pktout);
-
- crWaitUntilV(pktin);
-
- if (pktin->type != SSH2_MSG_REQUEST_SUCCESS) {
- if (pktin->type != SSH2_MSG_REQUEST_FAILURE) {
- bombout(("Unexpected response to port "
- "forwarding request: packet type %d",
- pktin->type));
- crStopV;
- }
- logevent("Server refused this port forwarding");
- } else {
- logevent("Remote port forwarding enabled");
- }
- }
- }
- sfree(sportdesc);
- }
- }
- }
+ ssh_setup_portfwd(ssh, &ssh->cfg);
/*
* Potentially enable agent forwarding.
ssh2_pkt_adduint32(s->pktout, 0); /* pixel width */
ssh2_pkt_adduint32(s->pktout, 0); /* pixel height */
ssh2_pkt_addstring_start(s->pktout);
- ssh2_pkt_addbyte(s->pktout, 128); /* TTY_OP_ISPEED */
+ parse_ttymodes(ssh, ssh->cfg.ttymodes,
+ ssh2_send_ttymode, (void *)s->pktout);
+ ssh2_pkt_addbyte(s->pktout, SSH2_TTY_OP_ISPEED);
ssh2_pkt_adduint32(s->pktout, ssh->ispeed);
- ssh2_pkt_addbyte(s->pktout, 129); /* TTY_OP_OSPEED */
+ ssh2_pkt_addbyte(s->pktout, SSH2_TTY_OP_OSPEED);
ssh2_pkt_adduint32(s->pktout, ssh->ospeed);
ssh2_pkt_addstring_data(s->pktout, "\0", 1); /* TTY_OP_END */
ssh2_pkt_send(ssh, s->pktout);
} else {
subsys = ssh->cfg.ssh_subsys;
cmd = ssh->cfg.remote_cmd_ptr;
+ if (!cmd) cmd = ssh->cfg.remote_cmd;
}
s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
/*
* Try to send data on all channels if we can.
*/
- for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
- int bufsize;
- if (c->closes)
- continue; /* don't send on closing channels */
- bufsize = ssh2_try_send(c);
- if (bufsize == 0) {
- switch (c->type) {
- case CHAN_MAINSESSION:
- /* stdin need not receive an unthrottle
- * notification since it will be polled */
- break;
- case CHAN_X11:
- x11_unthrottle(c->u.x11.s);
- break;
- case CHAN_AGENT:
- /* agent sockets are request/response and need no
- * buffer management */
- break;
- case CHAN_SOCKDATA:
- pfd_unthrottle(c->u.pfd.s);
- break;
- }
- }
- }
+ for (i = 0; NULL != (c = index234(ssh->channels, i)); i++)
+ ssh2_try_send_and_unthrottle(c);
}
}
}
/*
- * Handlers for SSH2 messages that might arrive at any moment.
+ * Handlers for SSH-2 messages that might arrive at any moment.
*/
-void ssh2_msg_disconnect(Ssh ssh, struct Packet *pktin)
+static void ssh2_msg_disconnect(Ssh ssh, struct Packet *pktin)
{
/* log reason code in disconnect message */
char *buf, *msg;
sfree(buf);
}
-void ssh2_msg_debug(Ssh ssh, struct Packet *pktin)
+static void ssh2_msg_debug(Ssh ssh, struct Packet *pktin)
{
/* log the debug message */
- char *buf, *msg;
+ char *msg;
int msglen;
int always_display;
always_display = ssh2_pkt_getbool(pktin);
ssh_pkt_getstring(pktin, &msg, &msglen);
- buf = dupprintf("Remote debug message: %.*s", msglen, msg);
- logevent(buf);
- sfree(buf);
+ logeventf(ssh, "Remote debug message: %.*s", msglen, msg);
}
-void ssh2_msg_something_unimplemented(Ssh ssh, struct Packet *pktin)
+static void ssh2_msg_something_unimplemented(Ssh ssh, struct Packet *pktin)
{
struct Packet *pktout;
pktout = ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED);
}
/*
- * Handle the top-level SSH2 protocol.
+ * Handle the top-level SSH-2 protocol.
*/
static void ssh2_protocol_setup(Ssh ssh)
{
* These special message types we install handlers for.
*/
ssh->packet_dispatch[SSH2_MSG_DISCONNECT] = ssh2_msg_disconnect;
- ssh->packet_dispatch[SSH2_MSG_IGNORE] = ssh_msg_ignore; /* shared with ssh1 */
+ ssh->packet_dispatch[SSH2_MSG_IGNORE] = ssh_msg_ignore; /* shared with SSH-1 */
ssh->packet_dispatch[SSH2_MSG_DEBUG] = ssh2_msg_debug;
}
{
Ssh ssh = (Ssh)ctx;
- if (!ssh->kex_in_progress &&
+ if (ssh->state == SSH_STATE_CLOSED)
+ return;
+
+ if (!ssh->kex_in_progress && ssh->cfg.ssh_rekey_time != 0 &&
now - ssh->next_rekey >= 0) {
- do_ssh2_transport(ssh, "Initiating key re-exchange (timeout)",
- -1, NULL);
+ do_ssh2_transport(ssh, "timeout", -1, NULL);
}
}
-static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen,
+static void ssh2_protocol(Ssh ssh, void *vin, int inlen,
struct Packet *pktin)
{
+ unsigned char *in = (unsigned char *)vin;
if (ssh->state == SSH_STATE_CLOSED)
return;
if (pktin) {
ssh->incoming_data_size += pktin->encrypted_len;
if (!ssh->kex_in_progress &&
- ssh->incoming_data_size > MAX_DATA_BEFORE_REKEY)
- do_ssh2_transport(ssh, "Initiating key re-exchange "
- "(too much data received)", -1, NULL);
+ ssh->max_data_size != 0 &&
+ ssh->incoming_data_size > ssh->max_data_size)
+ do_ssh2_transport(ssh, "too much data received", -1, NULL);
}
if (pktin && ssh->packet_dispatch[pktin->type]) {
ssh->kex_ctx = NULL;
ssh->hostkey = NULL;
ssh->exitcode = -1;
+ ssh->close_expected = FALSE;
+ ssh->clean_exit = FALSE;
ssh->state = SSH_STATE_PREPACKET;
ssh->size_needed = FALSE;
ssh->eof_needed = FALSE;
ssh->do_ssh1_login_state = NULL;
ssh->do_ssh2_transport_state = NULL;
ssh->do_ssh2_authconn_state = NULL;
+ ssh->v_c = NULL;
+ ssh->v_s = NULL;
ssh->mainchan = NULL;
ssh->throttled_all = 0;
ssh->v1_stdout_throttling = 0;
ssh->queue = NULL;
ssh->queuelen = ssh->queuesize = 0;
ssh->queueing = FALSE;
+ ssh->qhead = ssh->qtail = NULL;
+ ssh->deferred_rekey_reason = NULL;
+ bufchain_init(&ssh->queued_incoming_data);
+ ssh->frozen = FALSE;
*backend_handle = ssh;
ssh->channels = NULL;
ssh->rportfwds = NULL;
+ ssh->portfwds = NULL;
ssh->send_ok = 0;
ssh->editing = 0;
ssh->incoming_data_size = ssh->outgoing_data_size =
ssh->deferred_data_size = 0L;
+ ssh->max_data_size = parse_blocksize(ssh->cfg.ssh_rekey_data);
ssh->kex_in_progress = FALSE;
p = connect_to_host(ssh, host, port, realhost, nodelay, keepalive);
ssh_free_packet(ssh->queue[ssh->queuelen]);
sfree(ssh->queue);
+ while (ssh->qhead) {
+ struct queued_handler *qh = ssh->qhead;
+ ssh->qhead = qh->next;
+ sfree(ssh->qhead);
+ }
+ ssh->qhead = ssh->qtail = NULL;
+
if (ssh->channels) {
while ((c = delpos234(ssh->channels, 0)) != NULL) {
switch (c->type) {
sfree(ssh->do_ssh1_login_state);
sfree(ssh->do_ssh2_transport_state);
sfree(ssh->do_ssh2_authconn_state);
+ sfree(ssh->v_c);
+ sfree(ssh->v_s);
if (ssh->crcda_ctx) {
crcda_free_context(ssh->crcda_ctx);
ssh->crcda_ctx = NULL;
}
if (ssh->s)
- ssh_do_close(ssh);
+ ssh_do_close(ssh, TRUE);
expire_timer_context(ssh);
if (ssh->pinger)
pinger_free(ssh->pinger);
+ bufchain_clear(&ssh->queued_incoming_data);
sfree(ssh);
random_unref();
/*
* Reconfigure the SSH backend.
- *
- * Currently, this function does nothing very useful. In future,
- * however, we could do some handy things with it. For example, we
- * could make the port forwarding configurer active in the Change
- * Settings box, and this routine could close down existing
- * forwardings and open up new ones in response to changes.
*/
static void ssh_reconfig(void *handle, Config *cfg)
{
Ssh ssh = (Ssh) handle;
+ char *rekeying = NULL, rekey_mandatory = FALSE;
+ unsigned long old_max_data_size;
+
pinger_reconfig(ssh->pinger, &ssh->cfg, cfg);
+ if (ssh->portfwds)
+ ssh_setup_portfwd(ssh, cfg);
+
+ if (ssh->cfg.ssh_rekey_time != cfg->ssh_rekey_time &&
+ cfg->ssh_rekey_time != 0) {
+ long new_next = ssh->last_rekey + cfg->ssh_rekey_time*60*TICKSPERSEC;
+ long now = GETTICKCOUNT();
+
+ if (new_next - now < 0) {
+ rekeying = "timeout shortened";
+ } else {
+ ssh->next_rekey = schedule_timer(new_next - now, ssh2_timer, ssh);
+ }
+ }
+
+ old_max_data_size = ssh->max_data_size;
+ ssh->max_data_size = parse_blocksize(cfg->ssh_rekey_data);
+ if (old_max_data_size != ssh->max_data_size &&
+ ssh->max_data_size != 0) {
+ if (ssh->outgoing_data_size > ssh->max_data_size ||
+ ssh->incoming_data_size > ssh->max_data_size)
+ rekeying = "data limit lowered";
+ }
+
+ if (ssh->cfg.compression != cfg->compression) {
+ rekeying = "compression setting changed";
+ rekey_mandatory = TRUE;
+ }
+
+ if (ssh->cfg.ssh2_des_cbc != cfg->ssh2_des_cbc ||
+ memcmp(ssh->cfg.ssh_cipherlist, cfg->ssh_cipherlist,
+ sizeof(ssh->cfg.ssh_cipherlist))) {
+ rekeying = "cipher settings changed";
+ rekey_mandatory = TRUE;
+ }
+
ssh->cfg = *cfg; /* STRUCTURE COPY */
+
+ if (rekeying) {
+ if (!ssh->kex_in_progress) {
+ do_ssh2_transport(ssh, rekeying, -1, NULL);
+ } else if (rekey_mandatory) {
+ ssh->deferred_rekey_reason = rekeying;
+ }
+ }
}
/*
- * Called to send data down the Telnet connection.
+ * Called to send data down the SSH connection.
*/
static int ssh_send(void *handle, char *buf, int len)
{
*/
static const struct telnet_special *ssh_get_specials(void *handle)
{
- static const struct telnet_special ignore_special[] = {
+ static const struct telnet_special ssh1_ignore_special[] = {
+ {"IGNORE message", TS_NOP}
+ };
+ static const struct telnet_special ssh2_transport_specials[] = {
{"IGNORE message", TS_NOP},
{"Repeat key exchange", TS_REKEY},
};
static const struct telnet_special ssh2_session_specials[] = {
{NULL, TS_SEP},
{"Break", TS_BRK},
- /* These are the signal names defined by draft-ietf-secsh-connect-19.
+ /* These are the signal names defined by draft-ietf-secsh-connect-23.
* They include all the ISO C signals, but are a subset of the POSIX
* required signals. */
{"SIGINT (Interrupt)", TS_SIGINT},
static const struct telnet_special specials_end[] = {
{NULL, TS_EXITMENU}
};
- static struct telnet_special ssh_specials[lenof(ignore_special) +
+ /* XXX review this length for any changes: */
+ static struct telnet_special ssh_specials[lenof(ssh2_transport_specials) +
lenof(ssh2_session_specials) +
lenof(specials_end)];
Ssh ssh = (Ssh) handle;
* won't cope with it, since we wouldn't bother sending it if
* asked anyway. */
if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
- ADD_SPECIALS(ignore_special);
+ ADD_SPECIALS(ssh1_ignore_special);
} else if (ssh->version == 2) {
- ADD_SPECIALS(ignore_special);
+ ADD_SPECIALS(ssh2_transport_specials);
if (ssh->mainchan)
ADD_SPECIALS(ssh2_session_specials);
} /* else we're not ready yet */
}
/*
- * Send Telnet special codes. TS_EOF is useful for `plink', so you
+ * Send special codes. TS_EOF is useful for `plink', so you
* can send an EOF and collect resulting output (e.g. `plink
* hostname sort').
*/
struct Packet *pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
ssh2_pkt_send(ssh, pktout);
+ ssh->send_ok = 0; /* now stop trying to read from stdin */
}
logevent("Sent EOF message");
} else if (code == TS_PING || code == TS_NOP) {
}
} else if (code == TS_REKEY) {
if (!ssh->kex_in_progress && ssh->version == 2) {
- do_ssh2_transport(ssh, "Initiating key re-exchange at"
- " user request", -1, NULL);
+ do_ssh2_transport(ssh, "at user request", -1, NULL);
}
} else if (code == TS_BRK) {
if (ssh->state == SSH_STATE_CLOSED
|| ssh->state == SSH_STATE_PREPACKET) return;
if (ssh->version == 1) {
- logevent("Unable to send BREAK signal in SSH1");
+ logevent("Unable to send BREAK signal in SSH-1");
} else if (ssh->mainchan) {
pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
c->ssh = ssh;
if (c) {
- c->remoteid = -1; /* to be set when open confirmed */
+ c->halfopen = TRUE;
c->localid = alloc_channel_id(ssh);
c->closes = 0;
c->type = CHAN_SOCKDATA_DORMANT;/* identify channel type */
PKT_INT, c->localid,
PKT_STR, hostname,
PKT_INT, port,
- //PKT_STR, <org:orgport>,
+ /* PKT_STR, <org:orgport>, */
PKT_END);
} else {
pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
ssh2_pkt_adduint32(pktout, c->localid);
c->v.v2.locwindow = OUR_V2_WINSIZE;
ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);/* our window size */
- ssh2_pkt_adduint32(pktout, 0x4000UL); /* our max pkt size */
+ ssh2_pkt_adduint32(pktout, OUR_V2_MAXPKT); /* our max pkt size */
ssh2_pkt_addstring(pktout, hostname);
ssh2_pkt_adduint32(pktout, port);
/*
}
/*
+ * cfg_info for SSH is the currently running version of the
+ * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
+ */
+static int ssh_cfg_info(void *handle)
+{
+ Ssh ssh = (Ssh) handle;
+ return ssh->version;
+}
+
+/*
* Gross hack: pscp will try to start SFTP but fall back to scp1 if
* that fails. This variable is the means by which scp.c can reach
* into the SSH code and find out which one it got.
ssh_provide_ldisc,
ssh_provide_logctx,
ssh_unthrottle,
+ ssh_cfg_info,
22
};
projects / u / mdw / putty / blobdiff