* Packet type contexts, so that ssh2_pkt_type can correctly decode
* the ambiguous type numbers back into the correct type strings.
*/
-#define SSH2_PKTCTX_DHGROUP1 0x0001
+#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
#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
#define translate(x) if (type == x) return #x
translate(SSH2_MSG_SERVICE_ACCEPT);
translate(SSH2_MSG_KEXINIT);
translate(SSH2_MSG_NEWKEYS);
- translatec(SSH2_MSG_KEXDH_INIT, SSH2_PKTCTX_DHGROUP1);
- translatec(SSH2_MSG_KEXDH_REPLY, SSH2_PKTCTX_DHGROUP1);
+ translatec(SSH2_MSG_KEXDH_INIT, SSH2_PKTCTX_DHGROUP);
+ translatec(SSH2_MSG_KEXDH_REPLY, SSH2_PKTCTX_DHGROUP);
translatec(SSH2_MSG_KEX_DH_GEX_REQUEST, SSH2_PKTCTX_DHGEX);
translatec(SSH2_MSG_KEX_DH_GEX_GROUP, SSH2_PKTCTX_DHGEX);
translatec(SSH2_MSG_KEX_DH_GEX_INIT, SSH2_PKTCTX_DHGEX);
#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,
*
* - 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
-
-const static struct ssh_kex *kex_algs[] = {
- &ssh_diffiehellman_gex,
- &ssh_diffiehellman
-};
+#define OUR_V2_MAXPKT 0x4000UL
const static struct ssh_signkey *hostkey_algs[] = { &ssh_rsa, &ssh_dss };
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) )
+
+/*
+ * 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 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;
+ long forcepad; /* Force padding to at least this length */
int type;
unsigned long sequence;
unsigned char *data;
unsigned char *body;
long savedpos;
long maxlen;
+ 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, void *vin, int inlen,
+ struct Packet *pktin);
struct rdpkt1_state_tag {
long len, pad, biglen, to_read;
};
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;
tree234 *channels; /* indexed by local id */
struct ssh_channel *mainchan; /* primary session channel */
int exitcode;
+ int close_expected;
- tree234 *rportfwds;
+ tree234 *rportfwds, *portfwds;
enum {
SSH_STATE_PREPACKET,
int userpass_input_bufpos;
int userpass_input_echo;
- 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;
+
+ /*
+ * Track incoming and outgoing data sizes and time, for
+ * 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, last_rekey;
+ char *deferred_rekey_reason; /* points to STATIC string; don't free */
};
#define logevent(s) logevent(ssh->frontend, s)
#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); \
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;
st->pktin->data + st->cipherblk,
st->packetlen - st->cipherblk);
+ st->pktin->encrypted_len = st->packetlen;
+
/*
* Check the MAC.
*/
}
/*
- * SSH2 packet construction functions.
+ * SSH-2 packet construction functions.
*/
static void ssh2_pkt_ensure(struct Packet *pkt, int length)
{
{
struct Packet *pkt = ssh_new_packet();
pkt->length = 5;
+ pkt->forcepad = 0;
ssh2_pkt_addbyte(pkt, (unsigned char) pkt_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.
*/
/*
* 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;
ssh->cscipher->encrypt(ssh->cs_cipher_ctx,
pkt->data, pkt->length + padding);
+ pkt->encrypted_len = pkt->length + padding;
+
/* Ready-to-send packet starts at pkt->data. We return length. */
return pkt->length + padding + maclen;
}
*/
/*
- * 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)
{
backlog = sk_write(ssh->s, (char *)pkt->data, len);
if (backlog > SSH_MAX_BACKLOG)
ssh_throttle_all(ssh, 1, backlog);
+
+ ssh->outgoing_data_size += pkt->encrypted_len;
+ if (!ssh->kex_in_progress &&
+ 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)
{
}
memcpy(ssh->deferred_send_data + ssh->deferred_len, pkt->data, len);
ssh->deferred_len += len;
+ ssh->deferred_data_size += pkt->encrypted_len;
ssh_free_packet(pkt);
}
/*
- * 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.
else
ssh2_pkt_defer_noqueue(ssh, pkt);
}
+#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->deferred_send_data = NULL;
if (backlog > SSH_MAX_BACKLOG)
ssh_throttle_all(ssh, 1, backlog);
+
+ ssh->outgoing_data_size += ssh->deferred_data_size;
+ if (!ssh->kex_in_progress &&
+ 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.
*/
}
/*
- * 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");
+ logevent("We believe remote version has SSH-2 public-key-session-ID bug");
}
- if (ssh->cfg.sshbug_dhgex2 == FORCE_ON) {
+ if (ssh->cfg.sshbug_rekey2 == FORCE_ON ||
+ (ssh->cfg.sshbug_rekey2 == AUTO &&
+ (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)))) {
/*
- * 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");
+ }
+}
+
+/*
+ * The `software version' part of an SSH version string is required
+ * to contain no spaces or minus signs.
+ */
+static void ssh_fix_verstring(char *str)
+{
+ /* Eat "SSH-<protoversion>-". */
+ assert(*str == 'S'); str++;
+ assert(*str == 'S'); str++;
+ assert(*str == 'H'); str++;
+ assert(*str == '-'); str++;
+ while (*str && *str != '-') str++;
+ assert(*str == '-'); str++;
+
+ /* Convert minus signs and spaces in the remaining string into
+ * underscores. */
+ while (*str) {
+ if (*str == '-' || *str == ' ')
+ *str = '_';
+ str++;
}
}
ssh->rdpkt2_state.incoming_sequence = 0;
s->vstring[s->vslen] = 0;
- s->vstring[strcspn(s->vstring, "\r\n")] = '\0';/* remove EOL chars */
- {
- char *vlog;
- vlog = snewn(20 + s->vslen, char);
- sprintf(vlog, "Server version: %s", s->vstring);
- logevent(vlog);
- sfree(vlog);
- }
+ s->vstring[strcspn(s->vstring, "\015\012")] = '\0';/* remove EOL chars */
+ logeventf(ssh, "Server version: %s", s->vstring);
ssh_detect_bugs(ssh, s->vstring);
/*
crStop(0);
}
- if (s->proto2 && (ssh->cfg.sshprot >= 2 || !s->proto1)) {
- /*
- * Use v2 protocol.
- */
- char verstring[80], vlog[100];
- sprintf(verstring, "SSH-2.0-%s", sshver);
- SHA_Init(&ssh->exhashbase);
- /*
- * Hash our version string and their version string.
- */
- sha_string(&ssh->exhashbase, verstring, strlen(verstring));
- sha_string(&ssh->exhashbase, s->vstring, strcspn(s->vstring, "\r\n"));
- sprintf(vlog, "We claim version: %s", verstring);
- logevent(vlog);
- strcat(verstring, "\012");
- logevent("Using SSH protocol version 2");
- sk_write(ssh->s, verstring, strlen(verstring));
- ssh->protocol = ssh2_protocol;
- ssh2_protocol_setup(ssh);
- ssh->version = 2;
- ssh->s_rdpkt = ssh2_rdpkt;
- } else {
- /*
- * Use v1 protocol.
- */
- char verstring[80], vlog[100];
- sprintf(verstring, "SSH-%s-%s",
- (ssh_versioncmp(s->version, "1.5") <= 0 ? s->version : "1.5"),
- sshver);
- sprintf(vlog, "We claim version: %s", verstring);
- logevent(vlog);
- strcat(verstring, "\012");
-
- logevent("Using SSH protocol version 1");
+ {
+ char *verstring;
+
+ if (s->proto2 && (ssh->cfg.sshprot >= 2 || !s->proto1)) {
+ /*
+ * Construct a v2 version string.
+ */
+ verstring = dupprintf("SSH-2.0-%s\015\012", sshver);
+ ssh->version = 2;
+ } else {
+ /*
+ * Construct a v1 version string.
+ */
+ verstring = dupprintf("SSH-%s-%s\012",
+ (ssh_versioncmp(s->version, "1.5") <= 0 ?
+ s->version : "1.5"),
+ sshver);
+ ssh->version = 1;
+ }
+
+ ssh_fix_verstring(verstring);
+
+ if (ssh->version == 2) {
+ /*
+ * 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"));
+
+ /*
+ * Initialise SSH-2 protocol.
+ */
+ ssh->protocol = ssh2_protocol;
+ ssh2_protocol_setup(ssh);
+ ssh->s_rdpkt = ssh2_rdpkt;
+ } else {
+ /*
+ * Initialise SSH-1 protocol.
+ */
+ ssh->protocol = ssh1_protocol;
+ ssh1_protocol_setup(ssh);
+ ssh->s_rdpkt = ssh1_rdpkt;
+ }
+ logeventf(ssh, "We claim version: %.*s",
+ strcspn(verstring, "\015\012"), verstring);
sk_write(ssh->s, verstring, strlen(verstring));
- ssh->protocol = ssh1_protocol;
- ssh1_protocol_setup(ssh);
- ssh->version = 1;
- ssh->s_rdpkt = ssh1_rdpkt;
+ sfree(verstring);
}
+
+ logeventf(ssh, "Using SSH protocol version %d", ssh->version);
+
update_specials_menu(ssh->frontend);
ssh->state = SSH_STATE_BEFORE_SIZE;
ssh->pinger = pinger_new(&ssh->cfg, &ssh_backend, ssh);
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);
*/
if (datalen == 0)
crReturnV;
+
+ /*
+ * Process queued data if there is any.
+ */
+ ssh_process_queued_incoming_data(ssh);
+
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);
- }
+ if (ssh->frozen)
+ ssh_queue_incoming_data(ssh, &data, &datalen);
+
+ ssh_process_incoming_data(ssh, &data, &datalen);
+
if (ssh->state == SSH_STATE_CLOSED)
return;
}
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);
+ int need_notify = ssh_do_close(ssh, FALSE);
+
+ if (!error_msg && !ssh->close_expected) {
+ error_msg = "Server unexpectedly closed network connection";
+ }
+
+ if (need_notify)
+ notify_remote_exit(ssh->frontend);
+
if (error_msg) {
/* A socket error has occurred. */
logevent(error_msg);
connection_fatal(ssh->frontend, "%s", error_msg);
} else {
- /* Otherwise, the remote side closed the connection normally. */
+ logevent("Server closed network connection");
}
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,
/*
* 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.
+ * reusable in several places - even between SSH-1 and SSH-2.
*/
/* Set up a username or password input loop on a given buffer. */
do_ssh2_authconn(ssh, NULL, -1, NULL);
}
+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;
Bignum challenge;
char *commentp;
int commentlen;
+ int dlgret;
};
crState(do_ssh1_login_state);
crBegin(ssh->do_ssh1_login_crstate);
- random_init();
-
if (!pktin)
crWaitUntil(pktin);
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);
}
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->close_expected = TRUE;
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ 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->close_expected = TRUE;
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ crStop(0);
+ }
+ }
}
switch (s->cipher_type) {
* Terminate.
*/
logevent("No username provided. Abandoning session.");
+ ssh->close_expected = TRUE;
ssh_closing((Plug)ssh, NULL, 0, 0);
crStop(1);
}
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)) {
bombout(("TIS challenge packet was badly formed"));
crStop(0);
}
+ c_write_str(ssh, "Using TIS authentication.\r\n");
logevent("Received TIS challenge");
if (challengelen > sizeof(s->prompt) - 1)
challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
bombout(("CryptoCard challenge packet was badly formed"));
crStop(0);
}
+ c_write_str(ssh, "Using CryptoCard authentication.\r\n");
logevent("Received CryptoCard challenge");
if (challengelen > sizeof(s->prompt) - 1)
challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
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);
+ char *msg = dupprintf("Key is of wrong type (%s)",
+ key_type_to_str(type));
+ logevent(msg);
+ c_write_str(ssh, msg);
c_write_str(ssh, "\r\n");
+ sfree(msg);
s->tried_publickey = 1;
continue;
}
PKT_END);
logevent("Unable to authenticate");
connection_fatal(ssh->frontend, "Unable to authenticate");
+ ssh->close_expected = TRUE;
ssh_closing((Plug)ssh, NULL, 0, 0);
crStop(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 do_ssh1_connection(Ssh ssh, unsigned char *in, int inlen,
- struct Packet *pktin)
+static void ssh_queueing_handler(Ssh ssh, struct Packet *pktin)
{
- crBegin(ssh->do_ssh1_connection_crstate);
+ struct queued_handler *qh = ssh->qhead;
- if (ssh->cfg.agentfwd && agent_exists()) {
- logevent("Requesting agent forwarding");
- send_packet(ssh, SSH1_CMSG_AGENT_REQUEST_FORWARDING, 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) {
- logevent("Agent forwarding refused");
- } else {
- logevent("Agent forwarding enabled");
- ssh->agentfwd_enabled = TRUE;
+ 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;
}
- if (ssh->cfg.x11_forward) {
- char proto[20], data[64];
- logevent("Requesting X11 forwarding");
- 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);
- if (ssh->v1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
- send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
- PKT_STR, proto, PKT_STR, data,
- 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);
+ 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;
}
- 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) {
- logevent("X11 forwarding refused");
- } else {
- logevent("X11 forwarding enabled");
- ssh->X11_fwd_enabled = TRUE;
+ 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;
+}
- {
- char type;
- int n;
+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;
- 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';
+ 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 < 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 (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);
}
}
- 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 {
+ 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 {
- logeventf(ssh, "Local port %s doing SOCKS"
- " dynamic forwarding", sportdesc);
+ 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 {
- 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, ")");
+ 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, sport,
- PKT_STR, host,
- PKT_INT, dport,
+ PKT_INT, epf->sport,
+ PKT_STR, epf->daddr,
+ PKT_INT, epf->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");
+ 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");
}
- logevent("Remote port forwarding enabled");
+ 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(sportdesc);
+ sfree(dportdesc);
+ }
+}
+
+static void ssh1_smsg_stdout_stderr_data(Ssh ssh, struct Packet *pktin)
+{
+ char *string;
+ int stringlen, bufsize;
+
+ ssh_pkt_getstring(pktin, &string, &stringlen);
+ if (string == NULL) {
+ bombout(("Incoming terminal data packet was badly formed"));
+ return;
+ }
+
+ bufsize = from_backend(ssh->frontend, pktin->type == SSH1_SMSG_STDERR_DATA,
+ string, stringlen);
+ if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
+ ssh->v1_stdout_throttling = 1;
+ ssh1_throttle(ssh, +1);
+ }
+}
+
+static void ssh1_smsg_x11_open(Ssh ssh, struct Packet *pktin)
+{
+ /* Remote side is trying to open a channel to talk to our
+ * X-Server. Give them back a local channel number. */
+ struct ssh_channel *c;
+ int remoteid = ssh_pkt_getuint32(pktin);
+
+ logevent("Received X11 connect request");
+ /* Refuse if X11 forwarding is disabled. */
+ if (!ssh->X11_fwd_enabled) {
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
+ PKT_INT, remoteid, PKT_END);
+ logevent("Rejected X11 connect request");
+ } else {
+ c = snew(struct ssh_channel);
+ c->ssh = ssh;
+
+ if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
+ ssh->x11auth, NULL, -1, &ssh->cfg) != NULL) {
+ logevent("Opening X11 forward connection failed");
+ sfree(c);
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
+ PKT_INT, remoteid, PKT_END);
+ } else {
+ 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->type = CHAN_X11; /* identify channel type */
+ add234(ssh->channels, c);
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
+ PKT_INT, c->remoteid, PKT_INT,
+ c->localid, PKT_END);
+ logevent("Opened X11 forward channel");
}
}
+}
+
+static void ssh1_smsg_agent_open(Ssh ssh, struct Packet *pktin)
+{
+ /* Remote side is trying to open a channel to talk to our
+ * agent. Give them back a local channel number. */
+ struct ssh_channel *c;
+ int remoteid = ssh_pkt_getuint32(pktin);
+
+ /* Refuse if agent forwarding is disabled. */
+ if (!ssh->agentfwd_enabled) {
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
+ PKT_INT, remoteid, PKT_END);
+ } else {
+ 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;
+ c->type = CHAN_AGENT; /* identify channel type */
+ c->u.a.lensofar = 0;
+ add234(ssh->channels, c);
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
+ PKT_INT, c->remoteid, PKT_INT, c->localid,
+ PKT_END);
+ }
+}
+
+static void ssh1_msg_port_open(Ssh ssh, struct Packet *pktin)
+{
+ /* 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, *pfp;
+ int remoteid;
+ int hostsize, port;
+ char *host;
+ const char *e;
+ c = snew(struct ssh_channel);
+ c->ssh = ssh;
+
+ remoteid = ssh_pkt_getuint32(pktin);
+ ssh_pkt_getstring(pktin, &host, &hostsize);
+ port = ssh_pkt_getuint32(pktin);
+
+ if (hostsize >= lenof(pf.dhost))
+ hostsize = lenof(pf.dhost)-1;
+ memcpy(pf.dhost, host, hostsize);
+ pf.dhost[hostsize] = '\0';
+ pf.dport = port;
+ pfp = find234(ssh->rportfwds, &pf, NULL);
+
+ 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 {
+ 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, pfp->pfrec->addressfamily);
+ if (e != NULL) {
+ 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->type = CHAN_SOCKDATA; /* identify channel type */
+ add234(ssh->channels, c);
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
+ PKT_INT, c->remoteid, PKT_INT,
+ c->localid, PKT_END);
+ logevent("Forwarded port opened successfully");
+ }
+ }
+}
+
+static void ssh1_msg_channel_open_confirmation(Ssh ssh, struct Packet *pktin)
+{
+ unsigned int remoteid = ssh_pkt_getuint32(pktin);
+ unsigned int localid = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+
+ 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);
+ }
+
+ if (c && c->closes) {
+ /*
+ * We have a pending close on this channel,
+ * which we decided on before the server acked
+ * the channel open. So now we know the
+ * remoteid, we can close it again.
+ */
+ send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE,
+ PKT_INT, c->remoteid, PKT_END);
+ }
+}
+
+static void ssh1_msg_channel_open_failure(Ssh ssh, struct Packet *pktin)
+{
+ unsigned int remoteid = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+
+ c = find234(ssh->channels, &remoteid, ssh_channelfind);
+ if (c && c->type == CHAN_SOCKDATA_DORMANT) {
+ logevent("Forwarded connection refused by server");
+ pfd_close(c->u.pfd.s);
+ del234(ssh->channels, c);
+ sfree(c);
+ }
+}
+
+static void ssh1_msg_channel_close(Ssh ssh, struct Packet *pktin)
+{
+ /* Remote side closes a channel. */
+ unsigned i = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (c && !c->halfopen) {
+ int closetype;
+ closetype =
+ (pktin->type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
+
+ if ((c->closes == 0) && (c->type == CHAN_X11)) {
+ logevent("Forwarded X11 connection terminated");
+ assert(c->u.x11.s != NULL);
+ x11_close(c->u.x11.s);
+ c->u.x11.s = NULL;
+ }
+ if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
+ logevent("Forwarded port closed");
+ assert(c->u.pfd.s != NULL);
+ pfd_close(c->u.pfd.s);
+ c->u.pfd.s = NULL;
+ }
+
+ c->closes |= (closetype << 2); /* seen this message */
+ if (!(c->closes & closetype)) {
+ send_packet(ssh, pktin->type, PKT_INT, c->remoteid,
+ PKT_END);
+ c->closes |= closetype; /* sent it too */
+ }
+
+ if (c->closes == 15) {
+ del234(ssh->channels, c);
+ sfree(c);
+ }
+ } else {
+ bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
+ pktin->type == SSH1_MSG_CHANNEL_CLOSE ? "" :
+ "_CONFIRMATION", c ? "half-open" : "nonexistent",
+ i));
+ }
+}
+
+static void ssh1_msg_channel_data(Ssh ssh, struct Packet *pktin)
+{
+ /* Data sent down one of our channels. */
+ int i = ssh_pkt_getuint32(pktin);
+ char *p;
+ int len;
+ struct ssh_channel *c;
+
+ ssh_pkt_getstring(pktin, &p, &len);
+
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (c) {
+ int bufsize = 0;
+ switch (c->type) {
+ case CHAN_X11:
+ bufsize = x11_send(c->u.x11.s, p, len);
+ break;
+ case CHAN_SOCKDATA:
+ bufsize = pfd_send(c->u.pfd.s, p, len);
+ break;
+ case CHAN_AGENT:
+ /* Data for an agent message. Buffer it. */
+ while (len > 0) {
+ if (c->u.a.lensofar < 4) {
+ unsigned int l = min(4 - c->u.a.lensofar, len);
+ memcpy(c->u.a.msglen + c->u.a.lensofar, p,
+ l);
+ p += l;
+ len -= l;
+ c->u.a.lensofar += l;
+ }
+ if (c->u.a.lensofar == 4) {
+ c->u.a.totallen =
+ 4 + GET_32BIT(c->u.a.msglen);
+ c->u.a.message = snewn(c->u.a.totallen,
+ unsigned char);
+ memcpy(c->u.a.message, c->u.a.msglen, 4);
+ }
+ if (c->u.a.lensofar >= 4 && len > 0) {
+ unsigned int l =
+ min(c->u.a.totallen - c->u.a.lensofar,
+ len);
+ memcpy(c->u.a.message + c->u.a.lensofar, p,
+ l);
+ p += l;
+ len -= l;
+ c->u.a.lensofar += l;
+ }
+ if (c->u.a.lensofar == c->u.a.totallen) {
+ void *reply;
+ int replylen;
+ if (agent_query(c->u.a.message,
+ c->u.a.totallen,
+ &reply, &replylen,
+ ssh_agentf_callback, c))
+ ssh_agentf_callback(c, reply, replylen);
+ sfree(c->u.a.message);
+ c->u.a.lensofar = 0;
+ }
+ }
+ bufsize = 0; /* agent channels never back up */
+ break;
+ }
+ if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
+ c->v.v1.throttling = 1;
+ ssh1_throttle(ssh, +1);
+ }
+ }
+}
+
+static void ssh1_smsg_exit_status(Ssh ssh, struct Packet *pktin)
+{
+ ssh->exitcode = ssh_pkt_getuint32(pktin);
+ 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
+ * extra human-readable text on the end of the
+ * session which we might mistake for another
+ * encrypted packet, we close the session once
+ * we've sent EXIT_CONFIRMATION.
+ */
+ ssh->close_expected = TRUE;
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+}
+
+static void do_ssh1_connection(Ssh ssh, unsigned char *in, int inlen,
+ struct Packet *pktin)
+{
+ crBegin(ssh->do_ssh1_connection_crstate);
+
+ ssh->packet_dispatch[SSH1_SMSG_STDOUT_DATA] =
+ ssh->packet_dispatch[SSH1_SMSG_STDERR_DATA] =
+ ssh1_smsg_stdout_stderr_data;
+
+ ssh->packet_dispatch[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION] =
+ ssh1_msg_channel_open_confirmation;
+ ssh->packet_dispatch[SSH1_MSG_CHANNEL_OPEN_FAILURE] =
+ ssh1_msg_channel_open_failure;
+ ssh->packet_dispatch[SSH1_MSG_CHANNEL_CLOSE] =
+ ssh->packet_dispatch[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION] =
+ ssh1_msg_channel_close;
+ ssh->packet_dispatch[SSH1_MSG_CHANNEL_DATA] = ssh1_msg_channel_data;
+ ssh->packet_dispatch[SSH1_SMSG_EXIT_STATUS] = ssh1_smsg_exit_status;
+
+ if (ssh->cfg.agentfwd && agent_exists()) {
+ logevent("Requesting agent forwarding");
+ send_packet(ssh, SSH1_CMSG_AGENT_REQUEST_FORWARDING, 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) {
+ logevent("Agent forwarding refused");
+ } else {
+ logevent("Agent forwarding enabled");
+ ssh->agentfwd_enabled = TRUE;
+ ssh->packet_dispatch[SSH1_SMSG_AGENT_OPEN] = ssh1_smsg_agent_open;
+ }
+ }
+
+ if (ssh->cfg.x11_forward) {
+ char proto[20], data[64];
+ logevent("Requesting X11 forwarding");
+ 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);
+ if (ssh->v1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
+ send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
+ PKT_STR, proto, PKT_STR, data,
+ 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);
+ }
+ 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) {
+ 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) {
/* Unpick the terminal-speed string. */
/*
* 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;
ssh->send_ok = 1;
ssh->channels = newtree234(ssh_channelcmp);
while (1) {
- crReturnV;
- if (pktin) {
- if (pktin->type == SSH1_SMSG_STDOUT_DATA ||
- pktin->type == SSH1_SMSG_STDERR_DATA) {
- char *string;
- int stringlen, bufsize;
-
- ssh_pkt_getstring(pktin, &string, &stringlen);
- if (string == NULL) {
- bombout(("Incoming terminal data packet was badly formed"));
- crStopV;
- }
- bufsize =
- from_backend(ssh->frontend,
- pktin->type == SSH1_SMSG_STDERR_DATA,
- string, stringlen);
- if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
- ssh->v1_stdout_throttling = 1;
- ssh1_throttle(ssh, +1);
- }
- } else if (pktin->type == SSH1_MSG_DISCONNECT) {
- ssh_closing((Plug)ssh, NULL, 0, 0);
- logevent("Received disconnect request");
- crStopV;
- } else if (pktin->type == SSH1_SMSG_X11_OPEN) {
- /* Remote side is trying to open a channel to talk to our
- * X-Server. Give them back a local channel number. */
- struct ssh_channel *c;
- int remoteid = ssh_pkt_getuint32(pktin);
-
- logevent("Received X11 connect request");
- /* Refuse if X11 forwarding is disabled. */
- if (!ssh->X11_fwd_enabled) {
- send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
- PKT_INT, remoteid, PKT_END);
- logevent("Rejected X11 connect request");
- } else {
- c = snew(struct ssh_channel);
- c->ssh = ssh;
-
- if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
- ssh->x11auth, NULL, -1, &ssh->cfg) != NULL) {
- logevent("Opening X11 forward connection failed");
- sfree(c);
- send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
- PKT_INT, remoteid, PKT_END);
- } else {
- logevent
- ("Opening X11 forward connection succeeded");
- c->remoteid = remoteid;
- c->localid = alloc_channel_id(ssh);
- c->closes = 0;
- c->v.v1.throttling = 0;
- c->type = CHAN_X11; /* identify channel type */
- add234(ssh->channels, c);
- send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
- PKT_INT, c->remoteid, PKT_INT,
- c->localid, PKT_END);
- logevent("Opened X11 forward channel");
- }
- }
- } else if (pktin->type == SSH1_SMSG_AGENT_OPEN) {
- /* Remote side is trying to open a channel to talk to our
- * agent. Give them back a local channel number. */
- struct ssh_channel *c;
- int remoteid = ssh_pkt_getuint32(pktin);
-
- /* Refuse if agent forwarding is disabled. */
- if (!ssh->agentfwd_enabled) {
- send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
- PKT_INT, remoteid, PKT_END);
- } else {
- c = snew(struct ssh_channel);
- c->ssh = ssh;
- c->remoteid = remoteid;
- c->localid = alloc_channel_id(ssh);
- c->closes = 0;
- c->v.v1.throttling = 0;
- c->type = CHAN_AGENT; /* identify channel type */
- c->u.a.lensofar = 0;
- add234(ssh->channels, c);
- send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
- PKT_INT, c->remoteid, PKT_INT, c->localid,
- PKT_END);
- }
- } else if (pktin->type == SSH1_MSG_PORT_OPEN) {
- /* 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;
- int remoteid;
- int hostsize, port;
- char *host, buf[1024];
- const char *e;
- c = snew(struct ssh_channel);
- c->ssh = ssh;
-
- remoteid = ssh_pkt_getuint32(pktin);
- ssh_pkt_getstring(pktin, &host, &hostsize);
- port = ssh_pkt_getuint32(pktin);
-
- if (hostsize >= lenof(pf.dhost))
- hostsize = lenof(pf.dhost)-1;
- memcpy(pf.dhost, host, hostsize);
- pf.dhost[hostsize] = '\0';
- pf.dport = port;
-
- if (find234(ssh->rportfwds, &pf, NULL) == NULL) {
- sprintf(buf, "Rejected remote port open request for %s:%d",
- pf.dhost, port);
- logevent(buf);
- 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);
- e = pfd_newconnect(&c->u.pfd.s, pf.dhost, port,
- c, &ssh->cfg);
- if (e != NULL) {
- char buf[256];
- sprintf(buf, "Port open failed: %s", e);
- logevent(buf);
- sfree(c);
- send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
- PKT_INT, remoteid, PKT_END);
- } else {
- c->remoteid = remoteid;
- c->localid = alloc_channel_id(ssh);
- c->closes = 0;
- c->v.v1.throttling = 0;
- c->type = CHAN_SOCKDATA; /* identify channel type */
- add234(ssh->channels, c);
- send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
- PKT_INT, c->remoteid, PKT_INT,
- c->localid, PKT_END);
- logevent("Forwarded port opened successfully");
- }
- }
-
- } else if (pktin->type == SSH1_MSG_CHANNEL_OPEN_CONFIRMATION) {
- unsigned int remoteid = ssh_pkt_getuint32(pktin);
- unsigned int localid = ssh_pkt_getuint32(pktin);
- struct ssh_channel *c;
-
- c = find234(ssh->channels, &remoteid, ssh_channelfind);
- if (c && c->type == CHAN_SOCKDATA_DORMANT) {
- c->remoteid = localid;
- c->type = CHAN_SOCKDATA;
- c->v.v1.throttling = 0;
- pfd_confirm(c->u.pfd.s);
- }
-
- if (c && c->closes) {
- /*
- * We have a pending close on this channel,
- * which we decided on before the server acked
- * the channel open. So now we know the
- * remoteid, we can close it again.
- */
- send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE,
- PKT_INT, c->remoteid, PKT_END);
- }
-
- } else if (pktin->type == SSH1_MSG_CHANNEL_OPEN_FAILURE) {
- unsigned int remoteid = ssh_pkt_getuint32(pktin);
- struct ssh_channel *c;
-
- c = find234(ssh->channels, &remoteid, ssh_channelfind);
- if (c && c->type == CHAN_SOCKDATA_DORMANT) {
- logevent("Forwarded connection refused by server");
- pfd_close(c->u.pfd.s);
- del234(ssh->channels, c);
- sfree(c);
- }
-
- } else if (pktin->type == SSH1_MSG_CHANNEL_CLOSE ||
- pktin->type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
- /* Remote side closes a channel. */
- unsigned i = ssh_pkt_getuint32(pktin);
- struct ssh_channel *c;
- c = find234(ssh->channels, &i, ssh_channelfind);
- if (c && ((int)c->remoteid) != -1) {
- int closetype;
- closetype =
- (pktin->type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
-
- if ((c->closes == 0) && (c->type == CHAN_X11)) {
- logevent("Forwarded X11 connection terminated");
- assert(c->u.x11.s != NULL);
- x11_close(c->u.x11.s);
- c->u.x11.s = NULL;
- }
- if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
- logevent("Forwarded port closed");
- assert(c->u.pfd.s != NULL);
- pfd_close(c->u.pfd.s);
- c->u.pfd.s = NULL;
- }
-
- c->closes |= (closetype << 2); /* seen this message */
- if (!(c->closes & closetype)) {
- send_packet(ssh, pktin->type, PKT_INT, c->remoteid,
- PKT_END);
- c->closes |= closetype; /* sent it too */
- }
+ /*
+ * By this point, most incoming packets are already being
+ * handled by the dispatch table, and we need only pay
+ * attention to the unusual ones.
+ */
- if (c->closes == 15) {
- del234(ssh->channels, c);
- sfree(c);
- }
- } else {
- bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
- pktin->type == SSH1_MSG_CHANNEL_CLOSE ? "" :
- "_CONFIRMATION", c ? "half-open" : "nonexistent",
- i));
- crStopV;
- }
- } else if (pktin->type == SSH1_MSG_CHANNEL_DATA) {
- /* Data sent down one of our channels. */
- int i = ssh_pkt_getuint32(pktin);
- char *p;
- int len;
- struct ssh_channel *c;
-
- ssh_pkt_getstring(pktin, &p, &len);
-
- c = find234(ssh->channels, &i, ssh_channelfind);
- if (c) {
- int bufsize = 0;
- switch (c->type) {
- case CHAN_X11:
- bufsize = x11_send(c->u.x11.s, p, len);
- break;
- case CHAN_SOCKDATA:
- bufsize = pfd_send(c->u.pfd.s, p, len);
- break;
- case CHAN_AGENT:
- /* 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);
- memcpy(c->u.a.msglen + c->u.a.lensofar, p,
- l);
- p += l;
- len -= l;
- c->u.a.lensofar += l;
- }
- if (c->u.a.lensofar == 4) {
- c->u.a.totallen =
- 4 + GET_32BIT(c->u.a.msglen);
- c->u.a.message = snewn(c->u.a.totallen,
- unsigned char);
- memcpy(c->u.a.message, c->u.a.msglen, 4);
- }
- if (c->u.a.lensofar >= 4 && len > 0) {
- int l =
- min(c->u.a.totallen - c->u.a.lensofar,
- len);
- memcpy(c->u.a.message + c->u.a.lensofar, p,
- l);
- p += l;
- len -= l;
- c->u.a.lensofar += l;
- }
- if (c->u.a.lensofar == c->u.a.totallen) {
- void *reply;
- int replylen;
- if (agent_query(c->u.a.message,
- c->u.a.totallen,
- &reply, &replylen,
- ssh_agentf_callback, c))
- ssh_agentf_callback(c, reply, replylen);
- sfree(c->u.a.message);
- c->u.a.lensofar = 0;
- }
- }
- bufsize = 0; /* agent channels never back up */
- break;
- }
- if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
- c->v.v1.throttling = 1;
- ssh1_throttle(ssh, +1);
- }
- }
- } else if (pktin->type == SSH1_SMSG_SUCCESS) {
+ crReturnV;
+ if (pktin) {
+ if (pktin->type == SSH1_SMSG_SUCCESS) {
/* may be from EXEC_SHELL on some servers */
} else if (pktin->type == SSH1_SMSG_FAILURE) {
/* may be from EXEC_SHELL on some servers
* if no pty is available or in other odd cases. Ignore */
- } else if (pktin->type == SSH1_SMSG_EXIT_STATUS) {
- char buf[100];
- ssh->exitcode = ssh_pkt_getuint32(pktin);
- sprintf(buf, "Server sent command exit status %d",
- ssh->exitcode);
- logevent(buf);
- send_packet(ssh, SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
- /*
- * In case `helpful' firewalls or proxies tack
- * extra human-readable text on the end of the
- * session which we might mistake for another
- * encrypted packet, we close the session once
- * we've sent EXIT_CONFIRMATION.
- */
- ssh_closing((Plug)ssh, NULL, 0, 0);
- crStopV;
} else {
bombout(("Strange packet received: type %d", pktin->type));
crStopV;
}
/*
- * 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,
}
/*
- * 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;
int kex_init_value, kex_reply_value;
const struct ssh_mac **maclist;
int hostkeylen, siglen;
void *hkey; /* actual host key */
unsigned char exchange_hash[20];
+ int n_preferred_kex;
+ const struct ssh_kex *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;
- random_init();
- 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)
*/
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
ssh->queueing = TRUE;
/*
+ * Flag that KEX is in progress.
+ */
+ ssh->kex_in_progress = TRUE;
+
+ /*
* Construct and send our key exchange packet.
*/
s->pktout = ssh2_pkt_init(SSH2_MSG_KEXINIT);
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)
+ commalist_started = 0;
+ for (i = 0; i < s->n_preferred_kex; i++) {
+ const struct ssh_kex *k = s->preferred_kex[i];
+ if (!k) continue; /* warning flag */
+ if (commalist_started)
ssh2_pkt_addstring_str(s->pktout, ",");
+ ssh2_pkt_addstring_str(s->pktout, s->preferred_kex[i]->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. */
* 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_kex *k = s->preferred_kex[i];
+ if (!k) {
+ s->warn_kex = TRUE;
+ } else {
+ if (!preferred) preferred = k->name;
+ if (in_commasep_string(k->name, str, len))
+ ssh->kex = k;
}
+ 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->close_expected = TRUE;
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ 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->close_expected = TRUE;
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ 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->close_expected = TRUE;
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ crStop(0);
+ }
+ }
+
+ if (s->ignorepkt) /* first_kex_packet_follows */
+ crWaitUntil(pktin); /* Ignore packet */
}
/*
* If we're doing Diffie-Hellman group exchange, start by
* requesting a group.
*/
- if (ssh->kex == &ssh_diffiehellman_gex) {
+ if (!ssh->kex->pdata) {
logevent("Doing Diffie-Hellman group exchange");
ssh->pkt_ctx |= SSH2_PKTCTX_DHGEX;
/*
bombout(("unable to read mp-ints from incoming group packet"));
crStop(0);
}
- ssh->kex_ctx = dh_setup_group(s->p, s->g);
+ ssh->kex_ctx = dh_setup_gex(s->p, s->g);
s->kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
s->kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
} else {
- ssh->pkt_ctx |= SSH2_PKTCTX_DHGROUP1;
- ssh->kex_ctx = dh_setup_group1();
+ ssh->pkt_ctx |= SSH2_PKTCTX_DHGROUP;
+ ssh->kex_ctx = dh_setup_group(ssh->kex);
s->kex_init_value = SSH2_MSG_KEXDH_INIT;
s->kex_reply_value = SSH2_MSG_KEXDH_REPLY;
+ logeventf(ssh, "Using Diffie-Hellman with standard group \"%s\"",
+ ssh->kex->groupname);
}
logevent("Doing Diffie-Hellman key exchange");
/*
* 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);
+ /* We assume everything from now on will be quick, and it might
+ * involve user interaction. */
+ set_busy_status(ssh->frontend, BUSY_NOT);
+
sha_string(&ssh->exhash, s->hostkeydata, s->hostkeylen);
if (ssh->kex == &ssh_diffiehellman_gex) {
sha_uint32(&ssh->exhash, s->pbits);
*/
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->close_expected = TRUE;
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ crStop(0);
+ }
+ if (!s->got_session_id) { /* don't bother logging this in rekeys */
logevent("Host key fingerprint is:");
logevent(s->fingerprint);
}
ssh->hostkey->freekey(s->hkey);
/*
+ * The exchange hash from the very first key exchange is also
+ * the session id, used in session key construction and
+ * authentication.
+ */
+ if (!s->got_session_id) {
+ memcpy(ssh->v2_session_id, s->exchange_hash,
+ sizeof(s->exchange_hash));
+ s->got_session_id = TRUE;
+ }
+
+ /*
* Send SSH2_MSG_NEWKEYS.
*/
s->pktout = ssh2_pkt_init(SSH2_MSG_NEWKEYS);
ssh2_pkt_send_noqueue(ssh, s->pktout);
+ ssh->outgoing_data_size = 0; /* start counting from here */
+
+ /*
+ * We've sent client NEWKEYS, so create and initialise
+ * client-to-server session keys.
+ */
+ if (ssh->cs_cipher_ctx)
+ ssh->cscipher->free_context(ssh->cs_cipher_ctx);
+ ssh->cscipher = s->cscipher_tobe;
+ ssh->cs_cipher_ctx = ssh->cscipher->make_context();
+
+ if (ssh->cs_mac_ctx)
+ ssh->csmac->free_context(ssh->cs_mac_ctx);
+ ssh->csmac = s->csmac_tobe;
+ ssh->cs_mac_ctx = ssh->csmac->make_context();
+
+ if (ssh->cs_comp_ctx)
+ ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
+ ssh->cscomp = s->cscomp_tobe;
+ ssh->cs_comp_ctx = ssh->cscomp->compress_init();
+
+ /*
+ * Set IVs on client-to-server keys. Here we use the exchange
+ * hash from the _first_ key exchange.
+ */
+ {
+ unsigned char keyspace[40];
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'C',keyspace);
+ ssh->cscipher->setkey(ssh->cs_cipher_ctx, keyspace);
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'A',keyspace);
+ ssh->cscipher->setiv(ssh->cs_cipher_ctx, keyspace);
+ ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'E',keyspace);
+ ssh->csmac->setkey(ssh->cs_mac_ctx, keyspace);
+ }
+
+ logeventf(ssh, "Initialised %.200s client->server encryption",
+ ssh->cscipher->text_name);
+ logeventf(ssh, "Initialised %.200s client->server MAC algorithm",
+ ssh->csmac->text_name);
+ if (ssh->cscomp->text_name)
+ logeventf(ssh, "Initialised %s compression",
+ ssh->cscomp->text_name);
/*
* Now our end of the key exchange is complete, we can send all
bombout(("expected new-keys packet from server"));
crStop(0);
}
+ ssh->incoming_data_size = 0; /* start counting from here */
/*
- * Create and initialise session keys.
+ * We've seen server NEWKEYS, so create and initialise
+ * server-to-client session keys.
*/
- if (ssh->cs_cipher_ctx)
- ssh->cscipher->free_context(ssh->cs_cipher_ctx);
- ssh->cscipher = s->cscipher_tobe;
- ssh->cs_cipher_ctx = ssh->cscipher->make_context();
-
if (ssh->sc_cipher_ctx)
ssh->sccipher->free_context(ssh->sc_cipher_ctx);
ssh->sccipher = s->sccipher_tobe;
ssh->sc_cipher_ctx = ssh->sccipher->make_context();
- if (ssh->cs_mac_ctx)
- ssh->csmac->free_context(ssh->cs_mac_ctx);
- ssh->csmac = s->csmac_tobe;
- ssh->cs_mac_ctx = ssh->csmac->make_context();
-
if (ssh->sc_mac_ctx)
ssh->scmac->free_context(ssh->sc_mac_ctx);
ssh->scmac = s->scmac_tobe;
ssh->sc_mac_ctx = ssh->scmac->make_context();
- if (ssh->cs_comp_ctx)
- ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
- ssh->cscomp = s->cscomp_tobe;
- ssh->cs_comp_ctx = ssh->cscomp->compress_init();
-
if (ssh->sc_comp_ctx)
ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
ssh->sccomp = s->sccomp_tobe;
ssh->sc_comp_ctx = ssh->sccomp->decompress_init();
/*
- * Set IVs after keys. Here we use the exchange hash from the
- * _first_ key exchange.
+ * Set IVs on server-to-client keys. Here we use the exchange
+ * hash from the _first_ key exchange.
*/
{
unsigned char keyspace[40];
- if (s->first_kex)
- memcpy(ssh->v2_session_id, s->exchange_hash,
- sizeof(s->exchange_hash));
- ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'C',keyspace);
- ssh->cscipher->setkey(ssh->cs_cipher_ctx, keyspace);
ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'D',keyspace);
ssh->sccipher->setkey(ssh->sc_cipher_ctx, keyspace);
- ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'A',keyspace);
- ssh->cscipher->setiv(ssh->cs_cipher_ctx, keyspace);
ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'B',keyspace);
ssh->sccipher->setiv(ssh->sc_cipher_ctx, keyspace);
- ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'E',keyspace);
- ssh->csmac->setkey(ssh->cs_mac_ctx, keyspace);
ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'F',keyspace);
ssh->scmac->setkey(ssh->sc_mac_ctx, keyspace);
}
- logeventf(ssh, "Initialised %.200s client->server encryption",
- ssh->cscipher->text_name);
logeventf(ssh, "Initialised %.200s server->client encryption",
ssh->sccipher->text_name);
- logeventf(ssh, "Initialised %.200s client->server MAC algorithm",
- ssh->csmac->text_name);
logeventf(ssh, "Initialised %.200s server->client MAC algorithm",
ssh->scmac->text_name);
- if (ssh->cscomp->text_name)
- logeventf(ssh, "Initialised %s compression",
- ssh->cscomp->text_name);
if (ssh->sccomp->text_name)
logeventf(ssh, "Initialised %s decompression",
ssh->sccomp->text_name);
+
+ /*
+ * Free key exchange data.
+ */
freebn(s->f);
freebn(s->K);
if (ssh->kex == &ssh_diffiehellman_gex) {
}
/*
+ * 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->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
* SSH2_MSG_NEWKEYS packet to the next layer, not because it
* wants to see it but because it will need time to initialise
* exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
* it would only confuse the layer above.
*/
- if (!s->first_kex) {
+ if (s->activated_authconn) {
crReturn(1);
}
- s->first_kex = 0;
+ s->activated_authconn = TRUE;
/*
* Now we're encrypting. Begin returning 1 to the protocol main
* function so that other things can run on top of the
* transport. If we ever see a KEXINIT, we must go back to the
* start.
+ *
+ * We _also_ go back to the start if we see pktin==NULL and
+ * inlen==-1, because this is a special signal meaning
+ * `initiate client-driven rekey', and `in' contains a message
+ * giving the reason for the rekey.
*/
- while (!(pktin && pktin->type == SSH2_MSG_KEXINIT)) {
+ while (!((pktin && pktin->type == SSH2_MSG_KEXINIT) ||
+ (!pktin && inlen == -1))) {
+ wait_for_rekey:
crReturn(1);
}
- logevent("Server initiated key re-exchange");
+ if (pktin) {
+ logevent("Server initiated key re-exchange");
+ } else {
+ /*
+ * 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;
crFinish(1);
}
/*
- * 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) {
- struct Packet *pktout;
+ /*
+ * 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);
+ ssh2_pkt_adduint32(pktout, c->remoteid);
+ ssh2_pkt_adduint32(pktout, newwin - c->v.v2.locwindow);
+ ssh2_pkt_send(ssh, pktout);
+ c->v.v2.locwindow = newwin;
+ }
+}
+
+static void ssh2_msg_channel_window_adjust(Ssh ssh, struct Packet *pktin)
+{
+ unsigned i = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ 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)
+{
+ char *data;
+ int length;
+ unsigned i = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (!c)
+ return; /* nonexistent channel */
+ if (pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
+ ssh_pkt_getuint32(pktin) != SSH2_EXTENDED_DATA_STDERR)
+ return; /* extended but not stderr */
+ ssh_pkt_getstring(pktin, &data, &length);
+ if (data) {
+ int bufsize = 0;
+ c->v.v2.locwindow -= length;
+ switch (c->type) {
+ case CHAN_MAINSESSION:
+ bufsize =
+ from_backend(ssh->frontend, pktin->type ==
+ SSH2_MSG_CHANNEL_EXTENDED_DATA,
+ data, length);
+ break;
+ case CHAN_X11:
+ bufsize = x11_send(c->u.x11.s, data, length);
+ break;
+ case CHAN_SOCKDATA:
+ bufsize = pfd_send(c->u.pfd.s, data, length);
+ break;
+ case CHAN_AGENT:
+ while (length > 0) {
+ if (c->u.a.lensofar < 4) {
+ unsigned int l = min(4 - c->u.a.lensofar, length);
+ memcpy(c->u.a.msglen + c->u.a.lensofar,
+ data, l);
+ data += l;
+ length -= l;
+ c->u.a.lensofar += l;
+ }
+ if (c->u.a.lensofar == 4) {
+ c->u.a.totallen =
+ 4 + GET_32BIT(c->u.a.msglen);
+ c->u.a.message = snewn(c->u.a.totallen,
+ unsigned char);
+ memcpy(c->u.a.message, c->u.a.msglen, 4);
+ }
+ if (c->u.a.lensofar >= 4 && length > 0) {
+ unsigned int l =
+ min(c->u.a.totallen - c->u.a.lensofar,
+ length);
+ memcpy(c->u.a.message + c->u.a.lensofar,
+ data, l);
+ data += l;
+ length -= l;
+ c->u.a.lensofar += l;
+ }
+ if (c->u.a.lensofar == c->u.a.totallen) {
+ void *reply;
+ int replylen;
+ if (agent_query(c->u.a.message,
+ c->u.a.totallen,
+ &reply, &replylen,
+ ssh_agentf_callback, c))
+ ssh_agentf_callback(c, reply, replylen);
+ sfree(c->u.a.message);
+ c->u.a.lensofar = 0;
+ }
+ }
+ bufsize = 0;
+ break;
+ }
+ /*
+ * If we are not buffering too much data,
+ * enlarge the window again at the remote side.
+ */
+ if (bufsize < OUR_V2_WINSIZE)
+ ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
+ }
+}
+
+static void ssh2_msg_channel_eof(Ssh ssh, struct Packet *pktin)
+{
+ unsigned i = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (!c)
+ return; /* nonexistent channel */
+
+ if (c->type == CHAN_X11) {
+ /*
+ * Remote EOF on an X11 channel means we should
+ * wrap up and close the channel ourselves.
+ */
+ x11_close(c->u.x11.s);
+ sshfwd_close(c);
+ } else if (c->type == CHAN_AGENT) {
+ sshfwd_close(c);
+ } else if (c->type == CHAN_SOCKDATA) {
+ pfd_close(c->u.pfd.s);
+ sshfwd_close(c);
+ }
+}
+
+static void ssh2_msg_channel_close(Ssh ssh, struct Packet *pktin)
+{
+ unsigned i = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+ struct Packet *pktout;
+
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (!c || c->halfopen) {
+ bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
+ c ? "half-open" : "nonexistent", i));
+ return;
+ }
+ /* Do pre-close processing on the channel. */
+ switch (c->type) {
+ case CHAN_MAINSESSION:
+ ssh->mainchan = NULL;
+ update_specials_menu(ssh->frontend);
+ break;
+ case CHAN_X11:
+ if (c->u.x11.s != NULL)
+ x11_close(c->u.x11.s);
+ sshfwd_close(c);
+ break;
+ case CHAN_AGENT:
+ sshfwd_close(c);
+ break;
+ case CHAN_SOCKDATA:
+ if (c->u.pfd.s != NULL)
+ pfd_close(c->u.pfd.s);
+ sshfwd_close(c);
+ break;
+ }
+ if (c->closes == 0) {
+ pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
+ ssh2_pkt_adduint32(pktout, c->remoteid);
+ ssh2_pkt_send(ssh, pktout);
+ }
+ del234(ssh->channels, c);
+ bufchain_clear(&c->v.v2.outbuffer);
+ sfree(c);
+
+ /*
+ * See if that was the last channel left open.
+ * (This is only our termination condition if we're
+ * 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
+ * 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
+ * when you're done, and indeed OpenSSH feels
+ * 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->close_expected = TRUE;
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ }
+}
+
+static void ssh2_msg_channel_open_confirmation(Ssh ssh, struct Packet *pktin)
+{
+ unsigned i = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+ struct Packet *pktout;
+
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (!c)
+ return; /* nonexistent channel */
+ 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);
+ if (c->u.pfd.s)
+ pfd_confirm(c->u.pfd.s);
+ if (c->closes) {
+ /*
+ * We have a pending close on this channel,
+ * which we decided on before the server acked
+ * the channel open. So now we know the
+ * remoteid, we can close it again.
+ */
+ pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
+ ssh2_pkt_adduint32(pktout, c->remoteid);
+ ssh2_pkt_send(ssh, pktout);
+ }
+}
+
+static void ssh2_msg_channel_open_failure(Ssh ssh, struct Packet *pktin)
+{
+ static const char *const reasons[] = {
+ "<unknown reason code>",
+ "Administratively prohibited",
+ "Connect failed",
+ "Unknown channel type",
+ "Resource shortage",
+ };
+ unsigned i = ssh_pkt_getuint32(pktin);
+ unsigned reason_code;
+ char *reason_string;
+ int reason_length;
+ struct ssh_channel *c;
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (!c)
+ return; /* nonexistent channel */
+ if (c->type != CHAN_SOCKDATA_DORMANT)
+ return; /* dunno why they're failing this */
+
+ reason_code = ssh_pkt_getuint32(pktin);
+ if (reason_code >= lenof(reasons))
+ reason_code = 0; /* ensure reasons[reason_code] in range */
+ ssh_pkt_getstring(pktin, &reason_string, &reason_length);
+ logeventf(ssh, "Forwarded connection refused by server: %s [%.*s]",
+ reasons[reason_code], reason_length, reason_string);
+
+ pfd_close(c->u.pfd.s);
+
+ del234(ssh->channels, c);
+ sfree(c);
+}
+
+static void ssh2_msg_channel_request(Ssh ssh, struct Packet *pktin)
+{
+ unsigned localid;
+ char *type;
+ int typelen, want_reply;
+ int reply = SSH2_MSG_CHANNEL_FAILURE; /* default */
+ struct ssh_channel *c;
+ struct Packet *pktout;
+
+ localid = ssh_pkt_getuint32(pktin);
+ ssh_pkt_getstring(pktin, &type, &typelen);
+ want_reply = ssh2_pkt_getbool(pktin);
+
+ /*
+ * First, check that the channel exists. Otherwise,
+ * we can instantly disconnect with a rude message.
+ */
+ 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->close_expected = TRUE;
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ return;
+ }
+
+ /*
+ * Having got the channel number, we now look at
+ * the request type string to see if it's something
+ * we recognise.
+ */
+ if (c == ssh->mainchan) {
+ /*
+ * We recognise "exit-status" and "exit-signal" on
+ * the primary channel.
+ */
+ if (typelen == 11 &&
+ !memcmp(type, "exit-status", 11)) {
+
+ ssh->exitcode = ssh_pkt_getuint32(pktin);
+ logeventf(ssh, "Server sent command exit status %d",
+ ssh->exitcode);
+ reply = SSH2_MSG_CHANNEL_SUCCESS;
+
+ } else if (typelen == 11 &&
+ !memcmp(type, "exit-signal", 11)) {
+
+ int is_plausible = TRUE, is_int = FALSE;
+ char *fmt_sig = "", *fmt_msg = "";
+ char *msg;
+ int msglen = 0, core = FALSE;
+ /* ICK: older versions of OpenSSH (e.g. 3.4p1)
+ * provide an `int' for the signal, despite its
+ * having been a `string' in the drafts since at
+ * least 2001. (Fixed in session.c 1.147.) Try to
+ * infer which we can safely parse it as. */
+ {
+ unsigned char *p = pktin->body +
+ pktin->savedpos;
+ long len = pktin->length - pktin->savedpos;
+ unsigned long num = GET_32BIT(p); /* what is it? */
+ /* If it's 0, it hardly matters; assume string */
+ if (num == 0) {
+ is_int = FALSE;
+ } else {
+ int maybe_int = FALSE, maybe_str = FALSE;
+#define CHECK_HYPOTHESIS(offset, result) \
+ do { \
+ long q = offset; \
+ 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))!= 0) && q == len) \
+ result = TRUE; \
+ } \
+ } while(0)
+ CHECK_HYPOTHESIS(4+1, maybe_int);
+ CHECK_HYPOTHESIS(4+num+1, maybe_str);
+#undef CHECK_HYPOTHESIS
+ if (maybe_int && !maybe_str)
+ is_int = TRUE;
+ else if (!maybe_int && maybe_str)
+ is_int = FALSE;
+ else
+ /* Crikey. Either or neither. Panic. */
+ is_plausible = FALSE;
+ }
+ }
+ if (is_plausible) {
+ if (is_int) {
+ /* Old non-standard OpenSSH. */
+ int signum = ssh_pkt_getuint32(pktin);
+ fmt_sig = dupprintf(" %d", signum);
+ } else {
+ /* As per the drafts. */
+ char *sig;
+ int siglen;
+ ssh_pkt_getstring(pktin, &sig, &siglen);
+ /* Signal name isn't supposed to be blank, but
+ * let's cope gracefully if it is. */
+ if (siglen) {
+ fmt_sig = dupprintf(" \"%.*s\"",
+ siglen, sig);
+ }
+ }
+ core = ssh2_pkt_getbool(pktin);
+ ssh_pkt_getstring(pktin, &msg, &msglen);
+ if (msglen) {
+ fmt_msg = dupprintf(" (\"%.*s\")", msglen, msg);
+ }
+ /* ignore lang tag */
+ } /* else don't attempt to parse */
+ logeventf(ssh, "Server exited on signal%s%s%s",
+ fmt_sig, core ? " (core dumped)" : "",
+ fmt_msg);
+ if (*fmt_sig) sfree(fmt_sig);
+ if (*fmt_msg) sfree(fmt_msg);
+ reply = SSH2_MSG_CHANNEL_SUCCESS;
+
+ }
+ } else {
+ /*
+ * This is a channel request we don't know
+ * about, so we now either ignore the request
+ * or respond with CHANNEL_FAILURE, depending
+ * on want_reply.
+ */
+ reply = SSH2_MSG_CHANNEL_FAILURE;
+ }
+ if (want_reply) {
+ pktout = ssh2_pkt_init(reply);
+ ssh2_pkt_adduint32(pktout, c->remoteid);
+ ssh2_pkt_send(ssh, pktout);
+ }
+}
+
+static void ssh2_msg_global_request(Ssh ssh, struct Packet *pktin)
+{
+ char *type;
+ int typelen, want_reply;
+ struct Packet *pktout;
+
+ ssh_pkt_getstring(pktin, &type, &typelen);
+ want_reply = ssh2_pkt_getbool(pktin);
- pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
- ssh2_pkt_adduint32(pktout, c->remoteid);
- ssh2_pkt_adduint32(pktout, newwin - c->v.v2.locwindow);
+ /*
+ * We currently don't support any global requests
+ * at all, so we either ignore the request or
+ * respond with REQUEST_FAILURE, depending on
+ * want_reply.
+ */
+ if (want_reply) {
+ pktout = ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE);
ssh2_pkt_send(ssh, pktout);
- c->v.v2.locwindow = newwin;
}
}
-void ssh2_msg_channel_window_adjust(Ssh ssh, struct Packet *pktin)
+static void ssh2_msg_channel_open(Ssh ssh, struct Packet *pktin)
{
- unsigned i = ssh_pkt_getuint32(pktin);
+ char *type;
+ int typelen;
+ char *peeraddr;
+ int peeraddrlen;
+ int peerport;
+ char *error = NULL;
struct ssh_channel *c;
- c = find234(ssh->channels, &i, ssh_channelfind);
- if (c && !c->closes)
- c->v.v2.remwindow += ssh_pkt_getuint32(pktin);
+ unsigned remid, winsize, pktsize;
+ struct Packet *pktout;
+
+ ssh_pkt_getstring(pktin, &type, &typelen);
+ c = snew(struct ssh_channel);
+ c->ssh = ssh;
+
+ remid = ssh_pkt_getuint32(pktin);
+ winsize = ssh_pkt_getuint32(pktin);
+ pktsize = ssh_pkt_getuint32(pktin);
+
+ if (typelen == 3 && !memcmp(type, "x11", 3)) {
+ char *addrstr;
+
+ ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
+ addrstr = snewn(peeraddrlen+1, char);
+ memcpy(addrstr, peeraddr, peeraddrlen);
+ addrstr[peeraddrlen] = '\0';
+ peerport = ssh_pkt_getuint32(pktin);
+
+ logeventf(ssh, "Received X11 connect request from %s:%d",
+ addrstr, peerport);
+
+ if (!ssh->X11_fwd_enabled)
+ error = "X11 forwarding is not enabled";
+ else if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
+ ssh->x11auth, addrstr, peerport,
+ &ssh->cfg) != NULL) {
+ error = "Unable to open an X11 connection";
+ } else {
+ logevent("Opening X11 forward connection succeeded");
+ c->type = CHAN_X11;
+ }
+
+ sfree(addrstr);
+ } else if (typelen == 15 &&
+ !memcmp(type, "forwarded-tcpip", 15)) {
+ struct ssh_rportfwd pf, *realpf;
+ char *dummy;
+ int dummylen;
+ ssh_pkt_getstring(pktin, &dummy, &dummylen);/* skip address */
+ pf.sport = ssh_pkt_getuint32(pktin);
+ ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
+ peerport = ssh_pkt_getuint32(pktin);
+ realpf = find234(ssh->rportfwds, &pf, NULL);
+ logeventf(ssh, "Received remote port %d open request "
+ "from %s:%d", pf.sport, peeraddr, peerport);
+ if (realpf == NULL) {
+ error = "Remote port is not recognised";
+ } else {
+ const char *e = pfd_newconnect(&c->u.pfd.s,
+ realpf->dhost,
+ realpf->dport, c,
+ &ssh->cfg,
+ realpf->pfrec->addressfamily);
+ logeventf(ssh, "Attempting to forward remote port to "
+ "%s:%d", realpf->dhost, realpf->dport);
+ if (e != NULL) {
+ logeventf(ssh, "Port open failed: %s", e);
+ error = "Port open failed";
+ } else {
+ logevent("Forwarded port opened successfully");
+ c->type = CHAN_SOCKDATA;
+ }
+ }
+ } else if (typelen == 22 &&
+ !memcmp(type, "auth-agent@openssh.com", 3)) {
+ if (!ssh->agentfwd_enabled)
+ error = "Agent forwarding is not enabled";
+ else {
+ c->type = CHAN_AGENT; /* identify channel type */
+ c->u.a.lensofar = 0;
+ }
+ } else {
+ error = "Unsupported channel type requested";
+ }
+
+ 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, SSH2_OPEN_CONNECT_FAILED);
+ ssh2_pkt_addstring(pktout, error);
+ ssh2_pkt_addstring(pktout, "en"); /* language tag */
+ ssh2_pkt_send(ssh, pktout);
+ logeventf(ssh, "Rejected channel open: %s", error);
+ sfree(c);
+ } else {
+ c->localid = alloc_channel_id(ssh);
+ c->closes = 0;
+ c->v.v2.locwindow = OUR_V2_WINSIZE;
+ c->v.v2.remwindow = winsize;
+ c->v.v2.remmaxpkt = pktsize;
+ bufchain_init(&c->v.v2.outbuffer);
+ add234(ssh->channels, c);
+ pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
+ ssh2_pkt_adduint32(pktout, c->remoteid);
+ ssh2_pkt_adduint32(pktout, c->localid);
+ ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);
+ ssh2_pkt_adduint32(pktout, OUR_V2_MAXPKT); /* our max pkt size */
+ ssh2_pkt_send(ssh, pktout);
+ }
}
/*
- * Handle the SSH2 userauth and connection layers.
+ * 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_QUIET
} type;
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_running, kbd_inter_refused;
int we_are_in;
int num_prompts, curr_prompt, echo;
char username[100];
* Terminate.
*/
logevent("No username provided. Abandoning session.");
+ ssh->close_expected = TRUE;
ssh_closing((Plug)ssh, NULL, 0, 0);
crStopV;
}
s->tried_pubkey_config = FALSE;
s->tried_agent = FALSE;
- s->tried_keyb_inter = FALSE;
s->kbd_inter_running = FALSE;
+ s->kbd_inter_refused = 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;
*/
if (!s->gotit)
s->curr_prompt = 0;
+ } else 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));
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 &&
}
}
- if (!s->method && s->can_keyb_inter && !s->tried_keyb_inter) {
+ if (!s->method && s->can_keyb_inter && !s->kbd_inter_refused &&
+ !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;
s->gotit = TRUE;
logevent("Keyboard-interactive authentication refused");
s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
+ s->kbd_inter_refused = TRUE; /* don't try it again */
continue;
}
+ c_write_str(ssh, "Using keyboard-interactive authentication.\r\n");
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;
logevent("Unable to authenticate");
connection_fatal(ssh->frontend,
"Unable to authenticate");
+ ssh->close_expected = TRUE;
ssh_closing((Plug)ssh, NULL, 0, 0);
crStopV;
}
}
} else if (s->method == AUTH_PASSWORD) {
/*
- * 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.
+ * 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.
*
- * 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
+ * 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_addstring(s->pktout, s->password);
memset(s->password, 0, sizeof(s->password));
end_log_omission(ssh, s->pktout);
- ssh2_pkt_defer(ssh, s->pktout);
- /*
- * 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.
- */
- if (ssh->cscipher) {
- int stringlen, i;
-
- stringlen = (256 - ssh->deferred_len);
- stringlen += ssh->cscipher->blksize - 1;
- stringlen -= (stringlen % ssh->cscipher->blksize);
- if (ssh->cscomp) {
- /*
- * 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.
- */
- 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);
- }
- ssh2_pkt_defer(ssh, s->pktout);
- }
- ssh_pkt_defersend(ssh);
+ ssh2_pkt_send(ssh, s->pktout);
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);
+ s->pktout->forcepad = 256;
ssh2_pkt_adduint32(s->pktout, s->num_prompts);
}
if (s->need_pw) { /* only add pw if we just got one! */
" methods available");
ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
ssh2_pkt_send_noqueue(ssh, s->pktout);
+ ssh->close_expected = TRUE;
ssh_closing((Plug)ssh, NULL, 0, 0);
crStopV;
}
*/
ssh->packet_dispatch[SSH2_MSG_CHANNEL_WINDOW_ADJUST] =
ssh2_msg_channel_window_adjust;
+ ssh->packet_dispatch[SSH2_MSG_GLOBAL_REQUEST] =
+ ssh2_msg_global_request;
/*
* Create the main session channel.
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);
ssh->mainchan = NULL;
/*
+ * Now we have a channel, make dispatch table entries for
+ * general channel-based messages.
+ */
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_DATA] =
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_EXTENDED_DATA] =
+ ssh2_msg_channel_data;
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_EOF] = ssh2_msg_channel_eof;
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_CLOSE] = ssh2_msg_channel_close;
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION] =
+ ssh2_msg_channel_open_confirmation;
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_FAILURE] =
+ ssh2_msg_channel_open_failure;
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_REQUEST] =
+ ssh2_msg_channel_request;
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN] =
+ ssh2_msg_channel_open;
+
+ /*
* Potentially enable X11 forwarding.
*/
if (ssh->mainchan && ssh->cfg.x11_forward) {
/*
* 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.
} 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);
crReturnV;
s->try_send = FALSE;
if (pktin) {
- if (pktin->type == SSH2_MSG_CHANNEL_DATA ||
- pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
- char *data;
- int length;
- unsigned i = ssh_pkt_getuint32(pktin);
- struct ssh_channel *c;
- c = find234(ssh->channels, &i, ssh_channelfind);
- if (!c)
- continue; /* nonexistent channel */
- if (pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
- ssh_pkt_getuint32(pktin) != SSH2_EXTENDED_DATA_STDERR)
- continue; /* extended but not stderr */
- ssh_pkt_getstring(pktin, &data, &length);
- if (data) {
- int bufsize = 0;
- c->v.v2.locwindow -= length;
- switch (c->type) {
- case CHAN_MAINSESSION:
- bufsize =
- from_backend(ssh->frontend, pktin->type ==
- SSH2_MSG_CHANNEL_EXTENDED_DATA,
- data, length);
- break;
- case CHAN_X11:
- bufsize = x11_send(c->u.x11.s, data, length);
- break;
- case CHAN_SOCKDATA:
- bufsize = pfd_send(c->u.pfd.s, data, length);
- break;
- case CHAN_AGENT:
- while (length > 0) {
- if (c->u.a.lensofar < 4) {
- int l = min(4 - c->u.a.lensofar, length);
- memcpy(c->u.a.msglen + c->u.a.lensofar,
- data, l);
- data += l;
- length -= l;
- c->u.a.lensofar += l;
- }
- if (c->u.a.lensofar == 4) {
- c->u.a.totallen =
- 4 + GET_32BIT(c->u.a.msglen);
- c->u.a.message = snewn(c->u.a.totallen,
- unsigned char);
- memcpy(c->u.a.message, c->u.a.msglen, 4);
- }
- if (c->u.a.lensofar >= 4 && length > 0) {
- int l =
- min(c->u.a.totallen - c->u.a.lensofar,
- length);
- memcpy(c->u.a.message + c->u.a.lensofar,
- data, l);
- data += l;
- length -= l;
- c->u.a.lensofar += l;
- }
- if (c->u.a.lensofar == c->u.a.totallen) {
- void *reply;
- int replylen;
- if (agent_query(c->u.a.message,
- c->u.a.totallen,
- &reply, &replylen,
- ssh_agentf_callback, c))
- ssh_agentf_callback(c, reply, replylen);
- sfree(c->u.a.message);
- c->u.a.lensofar = 0;
- }
- }
- bufsize = 0;
- break;
- }
- /*
- * If we are not buffering too much data,
- * enlarge the window again at the remote side.
- */
- if (bufsize < OUR_V2_WINSIZE)
- ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
- }
- } else if (pktin->type == SSH2_MSG_CHANNEL_EOF) {
- unsigned i = ssh_pkt_getuint32(pktin);
- struct ssh_channel *c;
-
- c = find234(ssh->channels, &i, ssh_channelfind);
- if (!c)
- continue; /* nonexistent channel */
-
- if (c->type == CHAN_X11) {
- /*
- * Remote EOF on an X11 channel means we should
- * wrap up and close the channel ourselves.
- */
- x11_close(c->u.x11.s);
- sshfwd_close(c);
- } else if (c->type == CHAN_AGENT) {
- sshfwd_close(c);
- } else if (c->type == CHAN_SOCKDATA) {
- pfd_close(c->u.pfd.s);
- sshfwd_close(c);
- }
- } else if (pktin->type == SSH2_MSG_CHANNEL_CLOSE) {
- unsigned i = ssh_pkt_getuint32(pktin);
- struct ssh_channel *c;
-
- c = find234(ssh->channels, &i, ssh_channelfind);
- if (!c || ((int)c->remoteid) == -1) {
- bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
- c ? "half-open" : "nonexistent", i));
- crStopV;
- }
- /* Do pre-close processing on the channel. */
- switch (c->type) {
- case CHAN_MAINSESSION:
- ssh->mainchan = NULL;
- update_specials_menu(ssh->frontend);
- break;
- case CHAN_X11:
- if (c->u.x11.s != NULL)
- x11_close(c->u.x11.s);
- sshfwd_close(c);
- break;
- case CHAN_AGENT:
- sshfwd_close(c);
- break;
- case CHAN_SOCKDATA:
- if (c->u.pfd.s != NULL)
- pfd_close(c->u.pfd.s);
- sshfwd_close(c);
- break;
- }
- if (c->closes == 0) {
- s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
- ssh2_pkt_adduint32(s->pktout, c->remoteid);
- ssh2_pkt_send(ssh, s->pktout);
- }
- del234(ssh->channels, c);
- bufchain_clear(&c->v.v2.outbuffer);
- sfree(c);
-
- /*
- * See if that was the last channel left open.
- * (This is only our termination condition if we're
- * 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
- * being sent by at least one side; apparently
- * I was wrong and it's perfectly OK to
- * unceremoniously slam the connection shut
- * when you're done, and indeed OpenSSH feels
- * 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);
- crStopV;
- }
- continue; /* remote sends close; ignore (FIXME) */
- } else if (pktin->type == SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
- unsigned i = ssh_pkt_getuint32(pktin);
- struct ssh_channel *c;
- c = find234(ssh->channels, &i, ssh_channelfind);
- if (!c)
- continue; /* nonexistent channel */
- if (c->type != CHAN_SOCKDATA_DORMANT)
- continue; /* dunno why they're confirming this */
- c->remoteid = ssh_pkt_getuint32(pktin);
- c->type = CHAN_SOCKDATA;
- c->v.v2.remwindow = ssh_pkt_getuint32(pktin);
- c->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
- if (c->u.pfd.s)
- pfd_confirm(c->u.pfd.s);
- if (c->closes) {
- /*
- * We have a pending close on this channel,
- * which we decided on before the server acked
- * the channel open. So now we know the
- * remoteid, we can close it again.
- */
- s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
- ssh2_pkt_adduint32(s->pktout, c->remoteid);
- ssh2_pkt_send(ssh, s->pktout);
- }
- } else if (pktin->type == SSH2_MSG_CHANNEL_OPEN_FAILURE) {
- static const char *const reasons[] = {
- "<unknown reason code>",
- "Administratively prohibited",
- "Connect failed",
- "Unknown channel type",
- "Resource shortage",
- };
- unsigned i = 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)
- continue; /* nonexistent channel */
- if (c->type != CHAN_SOCKDATA_DORMANT)
- continue; /* dunno why they're failing this */
-
- reason_code = ssh_pkt_getuint32(pktin);
- 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);
-
- pfd_close(c->u.pfd.s);
-
- del234(ssh->channels, c);
- sfree(c);
- } else if (pktin->type == SSH2_MSG_CHANNEL_REQUEST) {
- unsigned localid;
- char *type;
- int typelen, want_reply;
- int reply = SSH2_MSG_CHANNEL_FAILURE; /* default */
- struct ssh_channel *c;
-
- localid = ssh_pkt_getuint32(pktin);
- ssh_pkt_getstring(pktin, &type, &typelen);
- want_reply = ssh2_pkt_getbool(pktin);
-
- /*
- * First, check that the channel exists. Otherwise,
- * we can instantly disconnect with a rude message.
- */
- c = find234(ssh->channels, &localid, ssh_channelfind);
- if (!c) {
- char buf[80];
- sprintf(buf, "Received channel request for nonexistent"
- " channel %d", localid);
- logevent(buf);
- s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
- ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
- ssh2_pkt_addstring(s->pktout, buf);
- ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
- ssh2_pkt_send_noqueue(ssh, s->pktout);
- connection_fatal(ssh->frontend, "%s", buf);
- ssh_closing((Plug)ssh, NULL, 0, 0);
- crStopV;
- }
-
- /*
- * Having got the channel number, we now look at
- * the request type string to see if it's something
- * we recognise.
- */
- if (c == ssh->mainchan) {
- /*
- * We recognise "exit-status" and "exit-signal" on
- * the primary channel.
- */
- if (typelen == 11 &&
- !memcmp(type, "exit-status", 11)) {
-
- ssh->exitcode = ssh_pkt_getuint32(pktin);
- logeventf(ssh, "Server sent command exit status %d",
- ssh->exitcode);
- reply = SSH2_MSG_CHANNEL_SUCCESS;
-
- } else if (typelen == 11 &&
- !memcmp(type, "exit-signal", 11)) {
-
- int is_plausible = TRUE, is_int = FALSE;
- char *fmt_sig = "", *fmt_msg = "";
- char *msg;
- int msglen = 0, core = FALSE;
- /* ICK: older versions of OpenSSH (e.g. 3.4p1)
- * provide an `int' for the signal, despite its
- * having been a `string' in the drafts since at
- * least 2001. (Fixed in session.c 1.147.) Try to
- * infer which we can safely parse it as. */
- {
- unsigned char *p = pktin->body +
- pktin->savedpos;
- long len = pktin->length - pktin->savedpos;
- unsigned long num = GET_32BIT(p); /* what is it? */
- /* If it's 0, it hardly matters; assume string */
- if (num == 0) {
- is_int = FALSE;
- } else {
- int maybe_int = FALSE, maybe_str = FALSE;
-#define CHECK_HYPOTHESIS(offset, result) \
- do { \
- long q = offset; \
- 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) \
- result = TRUE; \
- } \
- } while(0)
- CHECK_HYPOTHESIS(4+1, maybe_int);
- CHECK_HYPOTHESIS(4+num+1, maybe_str);
-#undef CHECK_HYPOTHESIS
- if (maybe_int && !maybe_str)
- is_int = TRUE;
- else if (!maybe_int && maybe_str)
- is_int = FALSE;
- else
- /* Crikey. Either or neither. Panic. */
- is_plausible = FALSE;
- }
- }
- if (is_plausible) {
- if (is_int) {
- /* Old non-standard OpenSSH. */
- int signum = ssh_pkt_getuint32(pktin);
- fmt_sig = dupprintf(" %d", signum);
- } else {
- /* As per the drafts. */
- char *sig;
- int siglen;
- ssh_pkt_getstring(pktin, &sig, &siglen);
- /* Signal name isn't supposed to be blank, but
- * let's cope gracefully if it is. */
- if (siglen) {
- fmt_sig = dupprintf(" \"%.*s\"",
- siglen, sig);
- }
- }
- core = ssh2_pkt_getbool(pktin);
- ssh_pkt_getstring(pktin, &msg, &msglen);
- if (msglen) {
- fmt_msg = dupprintf(" (\"%.*s\")", msglen, msg);
- }
- /* ignore lang tag */
- } /* else don't attempt to parse */
- logeventf(ssh, "Server exited on signal%s%s%s",
- fmt_sig, core ? " (core dumped)" : "",
- fmt_msg);
- if (*fmt_sig) sfree(fmt_sig);
- if (*fmt_msg) sfree(fmt_msg);
- reply = SSH2_MSG_CHANNEL_SUCCESS;
-
- }
- } else {
- /*
- * This is a channel request we don't know
- * about, so we now either ignore the request
- * or respond with CHANNEL_FAILURE, depending
- * on want_reply.
- */
- reply = SSH2_MSG_CHANNEL_FAILURE;
- }
- if (want_reply) {
- s->pktout = ssh2_pkt_init(reply);
- ssh2_pkt_adduint32(s->pktout, c->remoteid);
- ssh2_pkt_send(ssh, s->pktout);
- }
- } else if (pktin->type == SSH2_MSG_GLOBAL_REQUEST) {
- char *type;
- int typelen, want_reply;
-
- ssh_pkt_getstring(pktin, &type, &typelen);
- want_reply = ssh2_pkt_getbool(pktin);
-
- /*
- * We currently don't support any global requests
- * at all, so we either ignore the request or
- * respond with REQUEST_FAILURE, depending on
- * want_reply.
- */
- if (want_reply) {
- s->pktout = ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE);
- ssh2_pkt_send(ssh, s->pktout);
- }
- } else if (pktin->type == SSH2_MSG_CHANNEL_OPEN) {
- char *type;
- int typelen;
- char *peeraddr;
- int peeraddrlen;
- int peerport;
- char *error = NULL;
- struct ssh_channel *c;
- unsigned remid, winsize, pktsize;
- ssh_pkt_getstring(pktin, &type, &typelen);
- c = snew(struct ssh_channel);
- c->ssh = ssh;
-
- remid = ssh_pkt_getuint32(pktin);
- winsize = ssh_pkt_getuint32(pktin);
- pktsize = ssh_pkt_getuint32(pktin);
-
- if (typelen == 3 && !memcmp(type, "x11", 3)) {
- char *addrstr;
-
- ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
- addrstr = snewn(peeraddrlen+1, char);
- memcpy(addrstr, peeraddr, peeraddrlen);
- addrstr[peeraddrlen] = '\0';
- peerport = ssh_pkt_getuint32(pktin);
-
- logeventf(ssh, "Received X11 connect request from %s:%d",
- addrstr, peerport);
-
- if (!ssh->X11_fwd_enabled)
- error = "X11 forwarding is not enabled";
- else if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
- ssh->x11auth, addrstr, peerport,
- &ssh->cfg) != NULL) {
- error = "Unable to open an X11 connection";
- } else {
- logevent("Opening X11 forward connection succeeded");
- c->type = CHAN_X11;
- }
- sfree(addrstr);
- } else if (typelen == 15 &&
- !memcmp(type, "forwarded-tcpip", 15)) {
- struct ssh_rportfwd pf, *realpf;
- char *dummy;
- int dummylen;
- ssh_pkt_getstring(pktin, &dummy, &dummylen);/* skip address */
- pf.sport = ssh_pkt_getuint32(pktin);
- ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
- peerport = ssh_pkt_getuint32(pktin);
- realpf = find234(ssh->rportfwds, &pf, NULL);
- logeventf(ssh, "Received remote port %d open request "
- "from %s:%d", pf.sport, peeraddr, peerport);
- if (realpf == NULL) {
- error = "Remote port is not recognised";
- } else {
- const char *e = pfd_newconnect(&c->u.pfd.s,
- realpf->dhost,
- realpf->dport, c,
- &ssh->cfg);
- logeventf(ssh, "Attempting to forward remote port to "
- "%s:%d", realpf->dhost, realpf->dport);
- if (e != NULL) {
- logeventf(ssh, "Port open failed: %s", e);
- error = "Port open failed";
- } else {
- logevent("Forwarded port opened successfully");
- c->type = CHAN_SOCKDATA;
- }
- }
- } else if (typelen == 22 &&
- !memcmp(type, "auth-agent@openssh.com", 3)) {
- if (!ssh->agentfwd_enabled)
- error = "Agent forwarding is not enabled";
- else {
- c->type = CHAN_AGENT; /* identify channel type */
- c->u.a.lensofar = 0;
- }
- } else {
- error = "Unsupported channel type requested";
- }
+ /*
+ * _All_ the connection-layer packets we expect to
+ * receive are now handled by the dispatch table.
+ * Anything that reaches here must be bogus.
+ */
- c->remoteid = remid;
- if (error) {
- s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE);
- ssh2_pkt_adduint32(s->pktout, c->remoteid);
- ssh2_pkt_adduint32(s->pktout, SSH2_OPEN_CONNECT_FAILED);
- ssh2_pkt_addstring(s->pktout, error);
- ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
- ssh2_pkt_send(ssh, s->pktout);
- logeventf(ssh, "Rejected channel open: %s", error);
- sfree(c);
- } else {
- c->localid = alloc_channel_id(ssh);
- c->closes = 0;
- c->v.v2.locwindow = OUR_V2_WINSIZE;
- c->v.v2.remwindow = winsize;
- c->v.v2.remmaxpkt = pktsize;
- bufchain_init(&c->v.v2.outbuffer);
- add234(ssh->channels, c);
- s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
- ssh2_pkt_adduint32(s->pktout, c->remoteid);
- ssh2_pkt_adduint32(s->pktout, c->localid);
- ssh2_pkt_adduint32(s->pktout, c->v.v2.locwindow);
- ssh2_pkt_adduint32(s->pktout, 0x4000UL); /* our max pkt size */
- ssh2_pkt_send(ssh, s->pktout);
- }
- } else {
- bombout(("Strange packet received: type %d", pktin->type));
- crStopV;
- }
+ bombout(("Strange packet received: type %d", pktin->type));
+ crStopV;
} else if (ssh->mainchan) {
/*
* We have spare data. Add it to the channel buffer.
/*
* 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;
}
-static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen,
+static void ssh2_timer(void *ctx, long now)
+{
+ Ssh ssh = (Ssh)ctx;
+
+ 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, "timeout", -1, NULL);
+ }
+}
+
+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->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->packet_dispatch[pktin->type](ssh, pktin);
return;
ssh->kex_ctx = NULL;
ssh->hostkey = NULL;
ssh->exitcode = -1;
+ ssh->close_expected = FALSE;
ssh->state = SSH_STATE_PREPACKET;
ssh->size_needed = FALSE;
ssh->eof_needed = FALSE;
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->pinger = NULL;
+ 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);
if (p != NULL)
return p;
+ random_ref();
+
return NULL;
}
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(c);
}
freetree234(ssh->channels);
+ ssh->channels = NULL;
}
if (ssh->rportfwds) {
while ((pf = delpos234(ssh->rportfwds, 0)) != NULL)
sfree(pf);
freetree234(ssh->rportfwds);
+ ssh->rportfwds = NULL;
}
sfree(ssh->deferred_send_data);
if (ssh->x11auth)
ssh->crcda_ctx = NULL;
}
if (ssh->s)
- ssh_do_close(ssh);
- sfree(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);
+ 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;
+ }
+ }
}
/*
*/
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) {
- /* XXX add rekey, when implemented */
- ADD_SPECIALS(ignore_special);
+ ADD_SPECIALS(ssh2_transport_specials);
if (ssh->mainchan)
ADD_SPECIALS(ssh2_session_specials);
} /* else we're not ready yet */
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) {
ssh2_pkt_addstring_start(pktout);
ssh2_pkt_send_noqueue(ssh, pktout);
}
+ } else if (code == TS_REKEY) {
+ if (!ssh->kex_in_progress && ssh->version == 2) {
+ 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