#include <assert.h>
#include "putty.h"
+#include "terminal.h"
#include "tree234.h"
#include "ssh.h"
#define TRUE 1
#endif
-/* uncomment this for packet level debugging */
-/* #define DUMP_PACKETS */
-
#define logevent(s) { logevent(s); \
if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \
{ fprintf(stderr, "%s\n", s); fflush(stderr); } }
+/* logevent, only printf-formatted. */
+void logeventf(char *fmt, ...)
+{
+ va_list ap;
+ char stuff[200];
+
+ va_start(ap, fmt);
+ vsprintf(stuff, fmt, ap);
+ va_end(ap);
+ logevent(stuff);
+}
+
#define bombout(msg) ( ssh_state = SSH_STATE_CLOSED, \
(s ? sk_close(s), s = NULL : 0), \
- connection_fatal msg )
+ logeventf msg, connection_fatal msg )
#define SSH1_MSG_DISCONNECT 1 /* 0x1 */
#define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
#define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
#define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
#define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
+#define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
+#define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
#define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
#define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
#define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
#define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
#define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
+/*
+ * 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_DHGEX 0x0002
+#define SSH2_PKTCTX_PUBLICKEY 0x0010
+#define SSH2_PKTCTX_PASSWORD 0x0020
+#define SSH2_PKTCTX_KBDINTER 0x0040
+#define SSH2_PKTCTX_AUTH_MASK 0x00F0
+
#define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
#define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
#define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
*/
#define BUG_CHOKES_ON_SSH1_IGNORE 1
#define BUG_SSH2_HMAC 2
+#define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
+#define BUG_CHOKES_ON_RSA 8
+#define BUG_SSH2_RSA_PADDING 16
+#define BUG_SSH2_DERIVEKEY 32
+#define BUG_SSH2_DH_GEX 64
+
+static int ssh_pkt_ctx = 0;
+
+#define translate(x) if (type == x) return #x
+#define translatec(x,ctx) if (type == x && (ssh_pkt_ctx & ctx)) return #x
+char *ssh1_pkt_type(int type)
+{
+ translate(SSH1_MSG_DISCONNECT);
+ translate(SSH1_SMSG_PUBLIC_KEY);
+ translate(SSH1_CMSG_SESSION_KEY);
+ translate(SSH1_CMSG_USER);
+ translate(SSH1_CMSG_AUTH_RSA);
+ translate(SSH1_SMSG_AUTH_RSA_CHALLENGE);
+ translate(SSH1_CMSG_AUTH_RSA_RESPONSE);
+ translate(SSH1_CMSG_AUTH_PASSWORD);
+ translate(SSH1_CMSG_REQUEST_PTY);
+ translate(SSH1_CMSG_WINDOW_SIZE);
+ translate(SSH1_CMSG_EXEC_SHELL);
+ translate(SSH1_CMSG_EXEC_CMD);
+ translate(SSH1_SMSG_SUCCESS);
+ translate(SSH1_SMSG_FAILURE);
+ translate(SSH1_CMSG_STDIN_DATA);
+ translate(SSH1_SMSG_STDOUT_DATA);
+ translate(SSH1_SMSG_STDERR_DATA);
+ translate(SSH1_CMSG_EOF);
+ translate(SSH1_SMSG_EXIT_STATUS);
+ translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION);
+ translate(SSH1_MSG_CHANNEL_OPEN_FAILURE);
+ translate(SSH1_MSG_CHANNEL_DATA);
+ translate(SSH1_MSG_CHANNEL_CLOSE);
+ translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION);
+ translate(SSH1_SMSG_X11_OPEN);
+ translate(SSH1_CMSG_PORT_FORWARD_REQUEST);
+ translate(SSH1_MSG_PORT_OPEN);
+ translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING);
+ translate(SSH1_SMSG_AGENT_OPEN);
+ translate(SSH1_MSG_IGNORE);
+ translate(SSH1_CMSG_EXIT_CONFIRMATION);
+ translate(SSH1_CMSG_X11_REQUEST_FORWARDING);
+ translate(SSH1_CMSG_AUTH_RHOSTS_RSA);
+ translate(SSH1_MSG_DEBUG);
+ translate(SSH1_CMSG_REQUEST_COMPRESSION);
+ translate(SSH1_CMSG_AUTH_TIS);
+ translate(SSH1_SMSG_AUTH_TIS_CHALLENGE);
+ translate(SSH1_CMSG_AUTH_TIS_RESPONSE);
+ translate(SSH1_CMSG_AUTH_CCARD);
+ translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE);
+ translate(SSH1_CMSG_AUTH_CCARD_RESPONSE);
+ return "unknown";
+}
+char *ssh2_pkt_type(int type)
+{
+ translate(SSH2_MSG_DISCONNECT);
+ translate(SSH2_MSG_IGNORE);
+ translate(SSH2_MSG_UNIMPLEMENTED);
+ translate(SSH2_MSG_DEBUG);
+ translate(SSH2_MSG_SERVICE_REQUEST);
+ 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_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);
+ translatec(SSH2_MSG_KEX_DH_GEX_REPLY, SSH2_PKTCTX_DHGEX);
+ translate(SSH2_MSG_USERAUTH_REQUEST);
+ translate(SSH2_MSG_USERAUTH_FAILURE);
+ translate(SSH2_MSG_USERAUTH_SUCCESS);
+ translate(SSH2_MSG_USERAUTH_BANNER);
+ translatec(SSH2_MSG_USERAUTH_PK_OK, SSH2_PKTCTX_PUBLICKEY);
+ translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, SSH2_PKTCTX_PASSWORD);
+ translatec(SSH2_MSG_USERAUTH_INFO_REQUEST, SSH2_PKTCTX_KBDINTER);
+ translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE, SSH2_PKTCTX_KBDINTER);
+ translate(SSH2_MSG_GLOBAL_REQUEST);
+ translate(SSH2_MSG_REQUEST_SUCCESS);
+ translate(SSH2_MSG_REQUEST_FAILURE);
+ translate(SSH2_MSG_CHANNEL_OPEN);
+ translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
+ translate(SSH2_MSG_CHANNEL_OPEN_FAILURE);
+ translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
+ translate(SSH2_MSG_CHANNEL_DATA);
+ translate(SSH2_MSG_CHANNEL_EXTENDED_DATA);
+ translate(SSH2_MSG_CHANNEL_EOF);
+ translate(SSH2_MSG_CHANNEL_CLOSE);
+ translate(SSH2_MSG_CHANNEL_REQUEST);
+ translate(SSH2_MSG_CHANNEL_SUCCESS);
+ translate(SSH2_MSG_CHANNEL_FAILURE);
+ return "unknown";
+}
+#undef translate
+#undef translatec
#define GET_32BIT(cp) \
(((unsigned long)(unsigned char)(cp)[0] << 24) | \
extern char *x11_init(Socket *, char *, void *);
extern void x11_close(Socket);
-extern void x11_send(Socket, char *, int);
+extern int x11_send(Socket, char *, int);
extern void x11_invent_auth(char *, int, char *, int);
+extern void x11_unthrottle(Socket s);
+extern void x11_override_throttle(Socket s, int enable);
+
+extern char *pfd_newconnect(Socket * s, char *hostname, int port, void *c);
+extern char *pfd_addforward(char *desthost, int destport, int port);
+extern void pfd_close(Socket s);
+extern int pfd_send(Socket s, char *data, int len);
+extern void pfd_confirm(Socket s);
+extern void pfd_unthrottle(Socket s);
+extern void pfd_override_throttle(Socket s, int enable);
+
+static void ssh2_pkt_init(int pkt_type);
+static void ssh2_pkt_addbool(unsigned char value);
+static void ssh2_pkt_adduint32(unsigned long value);
+static void ssh2_pkt_addstring_start(void);
+static void ssh2_pkt_addstring_str(char *data);
+static void ssh2_pkt_addstring_data(char *data, int len);
+static void ssh2_pkt_addstring(char *data);
+static char *ssh2_mpint_fmt(Bignum b, int *len);
+static void ssh2_pkt_addmp(Bignum b);
+static int ssh2_pkt_construct(void);
+static void ssh2_pkt_send(void);
/*
- * Ciphers for SSH2. We miss out single-DES because it isn't
- * supported; also 3DES and Blowfish are both done differently from
- * SSH1. (3DES uses outer chaining; Blowfish has the opposite
- * endianness and different-sized keys.)
+ * Buffer management constants. There are several of these for
+ * various different purposes:
+ *
+ * - 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
+ * 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
+ * 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
+ * channels.
*/
-const static struct ssh2_ciphers *ciphers[] = {
- &ssh2_aes,
- &ssh2_blowfish,
- &ssh2_3des,
-};
+
+#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,
CHAN_MAINSESSION,
CHAN_X11,
CHAN_AGENT,
+ CHAN_SOCKDATA,
+ CHAN_SOCKDATA_DORMANT /* one the remote hasn't confirmed */
};
/*
struct ssh_channel {
unsigned remoteid, localid;
int type;
+ /*
+ * In SSH1, this value contains four bits:
+ *
+ * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
+ * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
+ * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
+ * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
+ *
+ * A channel is completely finished with when all four bits are set.
+ */
int closes;
- struct ssh2_data_channel {
- unsigned char *outbuffer;
- unsigned outbuflen, outbufsize;
- unsigned remwindow, remmaxpkt;
- } v2;
+ union {
+ struct ssh1_data_channel {
+ int throttling;
+ } v1;
+ struct ssh2_data_channel {
+ bufchain outbuffer;
+ unsigned remwindow, remmaxpkt;
+ unsigned locwindow;
+ } v2;
+ } v;
union {
struct ssh_agent_channel {
unsigned char *message;
struct ssh_x11_channel {
Socket s;
} x11;
+ struct ssh_pfd_channel {
+ Socket s;
+ } pfd;
} u;
};
+/*
+ * 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
+ * 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
+ * security hole if you're not on the ball: a malicious server
+ * could send you back _any_ host:port pair, so if you trustingly
+ * connect to the address it gives you then you've just opened the
+ * entire inside of your corporate network just by connecting
+ * through it to a dodgy SSH server. Hence, we must store a list of
+ * 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
+ * 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.
+ */
+struct ssh_rportfwd {
+ unsigned sport, dport;
+ char dhost[256];
+};
+
struct Packet {
long length;
int type;
static const struct ssh_kex *kex = NULL;
static const struct ssh_signkey *hostkey = NULL;
static unsigned char ssh2_session_id[20];
-int (*ssh_get_line) (const char *prompt, char *str, int maxlen,
- int is_pw) = NULL;
static char *savedhost;
static int savedport;
static int ssh_send_ok;
static int ssh_echoing, ssh_editing;
+static void *frontend;
+
static tree234 *ssh_channels; /* indexed by local id */
static struct ssh_channel *mainchan; /* primary session channel */
+static int ssh_exitcode = -1;
+
+static tree234 *ssh_rportfwds;
static enum {
SSH_STATE_PREPACKET,
static unsigned char *deferred_send_data = NULL;
static int deferred_len = 0, deferred_size = 0;
+/*
+ * 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.
+ */
+int ssh_fallback_cmd = 0;
+
static int ssh_version;
+static int ssh1_throttle_count;
+static int ssh_overall_bufsize;
+static int ssh_throttled_all;
+static int ssh1_stdout_throttling;
static void (*ssh_protocol) (unsigned char *in, int inlen, int ispkt);
static void ssh1_protocol(unsigned char *in, int inlen, int ispkt);
static void ssh2_protocol(unsigned char *in, int inlen, int ispkt);
static void ssh_size(void);
static void ssh_special(Telnet_Special);
-static void ssh2_try_send(struct ssh_channel *c);
+static int ssh2_try_send(struct ssh_channel *c);
static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
int len);
-
+static void ssh_throttle_all(int enable, int bufsize);
+static void ssh2_set_window(struct ssh_channel *c, unsigned newwin);
static int (*s_rdpkt) (unsigned char **data, int *datalen);
+static int ssh_sendbuffer(void);
static struct rdpkt1_state_tag {
long len, pad, biglen, to_read;
return 0;
}
+static int ssh_rportcmp_ssh1(void *av, void *bv)
+{
+ struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
+ struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
+ int i;
+ if ( (i = strcmp(a->dhost, b->dhost)) != 0)
+ return i < 0 ? -1 : +1;
+ if (a->dport > b->dport)
+ return +1;
+ if (a->dport < b->dport)
+ return -1;
+ return 0;
+}
+
+static int ssh_rportcmp_ssh2(void *av, void *bv)
+{
+ struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
+ struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
+
+ if (a->sport > b->sport)
+ return +1;
+ if (a->sport < b->sport)
+ return -1;
+ return 0;
+}
+
static int alloc_channel_id(void)
{
const unsigned CHANNEL_NUMBER_OFFSET = 256;
fputc(buf[i], stderr);
return;
}
- from_backend(1, buf, len);
+ from_backend(frontend, 1, buf, len);
}
static void c_write_untrusted(char *buf, int len)
(*data)++, (*datalen)--;
}
-#ifdef FWHACK
- if (st->len == 0x52656d6f) { /* "Remo"te server has closed ... */
- st->len = 0x300; /* big enough to carry to end */
- }
-#endif
-
st->pad = 8 - (st->len % 8);
st->biglen = st->len + st->pad;
pktin.length = st->len - 5;
st->to_read -= st->chunk;
}
+ if (cipher && detect_attack(pktin.data, st->biglen, NULL)) {
+ bombout(("Network attack (CRC compensation) detected!"));
+ crReturn(0);
+ }
+
if (cipher)
cipher->decrypt(pktin.data, st->biglen);
-#ifdef DUMP_PACKETS
- debug(("Got packet len=%d pad=%d\n", st->len, st->pad));
- dmemdump(pktin.data, st->biglen);
-#endif
st->realcrc = crc32(pktin.data, st->biglen - 4);
st->gotcrc = GET_32BIT(pktin.data + st->biglen - 4);
if (ssh1_compressing) {
unsigned char *decompblk;
int decomplen;
-#ifdef DUMP_PACKETS
- debug(("Packet payload pre-decompression:\n"));
- dmemdump(pktin.body - 1, pktin.length + 1);
-#endif
zlib_decompress_block(pktin.body - 1, pktin.length + 1,
&decompblk, &decomplen);
memcpy(pktin.body - 1, decompblk, decomplen);
sfree(decompblk);
pktin.length = decomplen - 1;
-#ifdef DUMP_PACKETS
- debug(("Packet payload post-decompression:\n"));
- dmemdump(pktin.body - 1, pktin.length + 1);
-#endif
}
+ pktin.type = pktin.body[-1];
+
+ log_packet(PKT_INCOMING, pktin.type, ssh1_pkt_type(pktin.type),
+ pktin.body, pktin.length);
+
if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
pktin.type == SSH1_SMSG_STDERR_DATA ||
pktin.type == SSH1_MSG_DEBUG ||
pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE ||
pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
- long strlen = GET_32BIT(pktin.body);
- if (strlen + 4 != pktin.length) {
+ long stringlen = GET_32BIT(pktin.body);
+ if (stringlen + 4 != pktin.length) {
bombout(("Received data packet with bogus string length"));
crReturn(0);
}
}
- pktin.type = pktin.body[-1];
-
if (pktin.type == SSH1_MSG_DEBUG) {
/* log debug message */
- char buf[80];
- int strlen = GET_32BIT(pktin.body);
- strcpy(buf, "Remote: ");
- if (strlen > 70)
- strlen = 70;
- memcpy(buf + 8, pktin.body + 4, strlen);
- buf[8 + strlen] = '\0';
+ char buf[512];
+ int stringlen = GET_32BIT(pktin.body);
+ strcpy(buf, "Remote debug message: ");
+ if (stringlen > 480)
+ stringlen = 480;
+ memcpy(buf + 8, pktin.body + 4, stringlen);
+ buf[8 + stringlen] = '\0';
logevent(buf);
goto next_packet;
} else if (pktin.type == SSH1_MSG_IGNORE) {
msglen = sizeof(buf) - nowlen - 1;
memcpy(buf + nowlen, pktin.body + 4, msglen);
buf[nowlen + msglen] = '\0';
- logevent(buf);
+ /* logevent(buf); (this is now done within the bombout macro) */
+ bombout(("Server sent disconnect message:\n\"%s\"", buf+nowlen));
+ crReturn(0);
}
crFinish(0);
pktin.data[st->i] = *(*data)++;
(*datalen)--;
}
-#ifdef FWHACK
- if (!memcmp(pktin.data, "Remo", 4)) { /* "Remo"te server has closed ... */
- /* FIXME */
- }
-#endif
+
if (sccipher)
sccipher->decrypt(pktin.data, st->cipherblk);
st->pad = pktin.data[4];
/*
+ * _Completely_ silly lengths should be stomped on before they
+ * do us any more damage.
+ */
+ if (st->len < 0 || st->pad < 0 || st->len + st->pad < 0) {
+ bombout(("Incoming packet was garbled on decryption"));
+ crReturn(0);
+ }
+
+ /*
* This enables us to deduce the payload length.
*/
st->payload = st->len - st->pad - 1;
sccipher->decrypt(pktin.data + st->cipherblk,
st->packetlen - st->cipherblk);
-#ifdef DUMP_PACKETS
- debug(("Got packet len=%d pad=%d\n", st->len, st->pad));
- dmemdump(pktin.data, st->packetlen);
-#endif
-
/*
* Check the MAC.
*/
}
pktin.length = 5 + newlen;
memcpy(pktin.data + 5, newpayload, newlen);
-#ifdef DUMP_PACKETS
- debug(("Post-decompression payload:\n"));
- dmemdump(pktin.data + 5, newlen);
-#endif
-
sfree(newpayload);
}
}
pktin.savedpos = 6;
pktin.type = pktin.data[5];
- if (pktin.type == SSH2_MSG_IGNORE || pktin.type == SSH2_MSG_DEBUG)
- goto next_packet; /* FIXME: print DEBUG message */
-
- if (pktin.type == SSH2_MSG_DISCONNECT) {
- /* log reason code in disconnect message */
- char buf[256];
- int reason = GET_32BIT(pktin.data + 6);
- unsigned msglen = GET_32BIT(pktin.data + 10);
- unsigned nowlen;
- if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) {
- sprintf(buf, "Received disconnect message (%s)",
- ssh2_disconnect_reasons[reason]);
- } else {
- sprintf(buf, "Received disconnect message (unknown type %d)",
- reason);
+ log_packet(PKT_INCOMING, pktin.type, ssh2_pkt_type(pktin.type),
+ pktin.data+6, pktin.length-6);
+
+ switch (pktin.type) {
+ /*
+ * These packets we must handle instantly.
+ */
+ case SSH2_MSG_DISCONNECT:
+ {
+ /* log reason code in disconnect message */
+ char buf[256];
+ int reason = GET_32BIT(pktin.data + 6);
+ unsigned msglen = GET_32BIT(pktin.data + 10);
+ unsigned nowlen;
+ if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) {
+ sprintf(buf, "Received disconnect message (%s)",
+ ssh2_disconnect_reasons[reason]);
+ } else {
+ sprintf(buf, "Received disconnect message (unknown type %d)",
+ reason);
+ }
+ logevent(buf);
+ strcpy(buf, "Disconnection message text: ");
+ nowlen = strlen(buf);
+ if (msglen > sizeof(buf) - nowlen - 1)
+ msglen = sizeof(buf) - nowlen - 1;
+ memcpy(buf + nowlen, pktin.data + 14, msglen);
+ buf[nowlen + msglen] = '\0';
+ logevent(buf);
+ bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
+ reason,
+ (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) ?
+ ssh2_disconnect_reasons[reason] : "unknown",
+ buf+nowlen));
+ crReturn(0);
+ }
+ break;
+ case SSH2_MSG_IGNORE:
+ goto next_packet;
+ case SSH2_MSG_DEBUG:
+ {
+ /* log the debug message */
+ char buf[512];
+ /* int display = pktin.body[6]; */
+ int stringlen = GET_32BIT(pktin.data+7);
+ int prefix;
+ strcpy(buf, "Remote debug message: ");
+ prefix = strlen(buf);
+ if (stringlen > sizeof(buf)-prefix-1)
+ stringlen = sizeof(buf)-prefix-1;
+ memcpy(buf + prefix, pktin.data + 11, stringlen);
+ buf[prefix + stringlen] = '\0';
+ logevent(buf);
}
- logevent(buf);
- strcpy(buf, "Disconnection message text: ");
- nowlen = strlen(buf);
- if (msglen > sizeof(buf) - nowlen - 1)
- msglen = sizeof(buf) - nowlen - 1;
- memcpy(buf + nowlen, pktin.data + 14, msglen);
- buf[nowlen + msglen] = '\0';
- logevent(buf);
+ goto next_packet; /* FIXME: print the debug message */
+
+ /*
+ * These packets we need do nothing about here.
+ */
+ case SSH2_MSG_UNIMPLEMENTED:
+ case SSH2_MSG_SERVICE_REQUEST:
+ case SSH2_MSG_SERVICE_ACCEPT:
+ case SSH2_MSG_KEXINIT:
+ case SSH2_MSG_NEWKEYS:
+ case SSH2_MSG_KEXDH_INIT:
+ case SSH2_MSG_KEXDH_REPLY:
+ /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
+ /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
+ case SSH2_MSG_KEX_DH_GEX_INIT:
+ case SSH2_MSG_KEX_DH_GEX_REPLY:
+ case SSH2_MSG_USERAUTH_REQUEST:
+ case SSH2_MSG_USERAUTH_FAILURE:
+ case SSH2_MSG_USERAUTH_SUCCESS:
+ case SSH2_MSG_USERAUTH_BANNER:
+ case SSH2_MSG_USERAUTH_PK_OK:
+ /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
+ /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
+ case SSH2_MSG_USERAUTH_INFO_RESPONSE:
+ case SSH2_MSG_GLOBAL_REQUEST:
+ case SSH2_MSG_REQUEST_SUCCESS:
+ case SSH2_MSG_REQUEST_FAILURE:
+ case SSH2_MSG_CHANNEL_OPEN:
+ case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
+ case SSH2_MSG_CHANNEL_OPEN_FAILURE:
+ case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
+ case SSH2_MSG_CHANNEL_DATA:
+ case SSH2_MSG_CHANNEL_EXTENDED_DATA:
+ case SSH2_MSG_CHANNEL_EOF:
+ case SSH2_MSG_CHANNEL_CLOSE:
+ case SSH2_MSG_CHANNEL_REQUEST:
+ case SSH2_MSG_CHANNEL_SUCCESS:
+ case SSH2_MSG_CHANNEL_FAILURE:
+ break;
+
+ /*
+ * For anything else we send SSH2_MSG_UNIMPLEMENTED.
+ */
+ default:
+ ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED);
+ ssh2_pkt_adduint32(st->incoming_sequence - 1);
+ ssh2_pkt_send();
+ break;
}
crFinish(0);
pktout.body[-1] = pktout.type;
-#ifdef DUMP_PACKETS
- debug(("Packet payload pre-compression:\n"));
- dmemdump(pktout.body - 1, pktout.length + 1);
-#endif
+ log_packet(PKT_OUTGOING, pktout.type, ssh1_pkt_type(pktout.type),
+ pktout.body, pktout.length);
if (ssh1_compressing) {
unsigned char *compblk;
ssh1_pktout_size(complen - 1);
memcpy(pktout.body - 1, compblk, complen);
sfree(compblk);
-#ifdef DUMP_PACKETS
- debug(("Packet payload post-compression:\n"));
- dmemdump(pktout.body - 1, pktout.length + 1);
-#endif
}
len = pktout.length + 5; /* type and CRC */
PUT_32BIT(pktout.data + biglen, crc);
PUT_32BIT(pktout.data, len);
-#ifdef DUMP_PACKETS
- debug(("Sending packet len=%d\n", biglen + 4));
- dmemdump(pktout.data, biglen + 4);
-#endif
if (cipher)
cipher->encrypt(pktout.data + 4, biglen);
static void s_wrpkt(void)
{
- int len;
+ int len, backlog;
len = s_wrpkt_prepare();
- sk_write(s, pktout.data, len);
+ backlog = sk_write(s, pktout.data, len);
+ if (backlog > SSH_MAX_BACKLOG)
+ ssh_throttle_all(1, backlog);
}
static void s_wrpkt_defer(void)
int cipherblk, maclen, padding, i;
static unsigned long outgoing_sequence = 0;
+ log_packet(PKT_OUTGOING, pktout.data[5], ssh2_pkt_type(pktout.data[5]),
+ pktout.data + 6, pktout.length - 6);
+
/*
* Compress packet payload.
*/
-#ifdef DUMP_PACKETS
- debug(("Pre-compression payload:\n"));
- dmemdump(pktout.data + 5, pktout.length - 5);
-#endif
{
unsigned char *newpayload;
int newlen;
outgoing_sequence);
outgoing_sequence++; /* whether or not we MACed */
-#ifdef DUMP_PACKETS
- debug(("Sending packet len=%d\n", pktout.length + padding));
- dmemdump(pktout.data, pktout.length + padding);
-#endif
-
if (cscipher)
cscipher->encrypt(pktout.data, pktout.length + padding);
*/
static void ssh2_pkt_send(void)
{
- int len = ssh2_pkt_construct();
- sk_write(s, pktout.data, len);
+ int len;
+ int backlog;
+ len = ssh2_pkt_construct();
+ backlog = sk_write(s, pktout.data, len);
+ if (backlog > SSH_MAX_BACKLOG)
+ ssh_throttle_all(1, backlog);
}
/*
*/
static void ssh_pkt_defersend(void)
{
- sk_write(s, deferred_send_data, deferred_len);
+ int backlog;
+ backlog = sk_write(s, deferred_send_data, deferred_len);
deferred_len = deferred_size = 0;
sfree(deferred_send_data);
deferred_send_data = NULL;
+ if (backlog > SSH_MAX_BACKLOG)
+ ssh_throttle_all(1, backlog);
}
#if 0
static void ssh2_pkt_getstring(char **p, int *length)
{
*p = NULL;
+ *length = 0;
if (pktin.length - pktin.savedpos < 4)
return;
*length = GET_32BIT(pktin.data + pktin.savedpos);
}
/*
+ * Helper function to add an SSH2 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
+ * BUG_SSH2_RSA_PADDING.
+ */
+static void ssh2_add_sigblob(void *pkblob_v, int pkblob_len,
+ void *sigblob_v, int sigblob_len)
+{
+ unsigned char *pkblob = (unsigned char *)pkblob_v;
+ unsigned char *sigblob = (unsigned char *)sigblob_v;
+
+ /* dmemdump(pkblob, pkblob_len); */
+ /* dmemdump(sigblob, sigblob_len); */
+
+ /*
+ * See if this is in fact an ssh-rsa signature and a buggy
+ * server; otherwise we can just do this the easy way.
+ */
+ if ((ssh_remote_bugs & BUG_SSH2_RSA_PADDING) &&
+ (GET_32BIT(pkblob) == 7 && !memcmp(pkblob+4, "ssh-rsa", 7))) {
+ int pos, len, siglen;
+
+ /*
+ * Find the byte length of the modulus.
+ */
+
+ pos = 4+7; /* skip over "ssh-rsa" */
+ pos += 4 + GET_32BIT(pkblob+pos); /* skip over exponent */
+ len = GET_32BIT(pkblob+pos); /* find length of modulus */
+ pos += 4; /* find modulus itself */
+ while (len > 0 && pkblob[pos] == 0)
+ len--, pos++;
+ /* debug(("modulus length is %d\n", len)); */
+
+ /*
+ * Now find the signature integer.
+ */
+ pos = 4+7; /* skip over "ssh-rsa" */
+ siglen = GET_32BIT(sigblob+pos);
+ /* debug(("signature length is %d\n", siglen)); */
+
+ if (len != siglen) {
+ unsigned char newlen[4];
+ ssh2_pkt_addstring_start();
+ ssh2_pkt_addstring_data(sigblob, pos);
+ /* dmemdump(sigblob, pos); */
+ pos += 4; /* point to start of actual sig */
+ PUT_32BIT(newlen, len);
+ ssh2_pkt_addstring_data(newlen, 4);
+ /* dmemdump(newlen, 4); */
+ newlen[0] = 0;
+ while (len-- > siglen) {
+ ssh2_pkt_addstring_data(newlen, 1);
+ /* dmemdump(newlen, 1); */
+ }
+ ssh2_pkt_addstring_data(sigblob+pos, siglen);
+ /* dmemdump(sigblob+pos, siglen); */
+ return;
+ }
+
+ /* Otherwise fall through and do it the easy way. */
+ }
+
+ ssh2_pkt_addstring_start();
+ ssh2_pkt_addstring_data(sigblob, sigblob_len);
+}
+
+/*
* Examine the remote side's version string and compare it against
* a list of known buggy implementations.
*/
char *imp; /* pointer to implementation part */
imp = vstring;
imp += strcspn(imp, "-");
- if (*imp)
- imp++;
+ if (*imp) imp++;
imp += strcspn(imp, "-");
- if (*imp)
- imp++;
+ if (*imp) imp++;
ssh_remote_bugs = 0;
- if (!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
- !strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") ||
- !strcmp(imp, "1.2.22")) {
+ if (cfg.sshbug_ignore1 == BUG_ON ||
+ (cfg.sshbug_ignore1 == BUG_AUTO &&
+ (!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
+ !strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") ||
+ !strcmp(imp, "1.2.22") || !strcmp(imp, "Cisco-1.25")))) {
/*
* These versions don't support SSH1_MSG_IGNORE, so we have
* to use a different defence against password length
logevent("We believe remote version has SSH1 ignore bug");
}
- if (!strncmp(imp, "2.1.0", 5) || !strncmp(imp, "2.0.", 4) ||
- !strncmp(imp, "2.2.0", 5) || !strncmp(imp, "2.3.0", 5) ||
- !strncmp(imp, "2.1 ", 4)) {
+ if (cfg.sshbug_plainpw1 == BUG_ON ||
+ (cfg.sshbug_plainpw1 == BUG_AUTO &&
+ (!strcmp(imp, "Cisco-1.25")))) {
+ /*
+ * These versions need a plain password sent; they can't
+ * handle having a null and a random length of data after
+ * the password.
+ */
+ ssh_remote_bugs |= BUG_NEEDS_SSH1_PLAIN_PASSWORD;
+ logevent("We believe remote version needs a plain SSH1 password");
+ }
+
+ if (cfg.sshbug_rsa1 == BUG_ON ||
+ (cfg.sshbug_rsa1 == BUG_AUTO &&
+ (!strcmp(imp, "Cisco-1.25")))) {
+ /*
+ * These versions apparently have no clue whatever about
+ * RSA authentication and will panic and die if they see
+ * an AUTH_RSA message.
+ */
+ ssh_remote_bugs |= BUG_CHOKES_ON_RSA;
+ logevent("We believe remote version can't handle RSA authentication");
+ }
+
+ if (cfg.sshbug_hmac2 == BUG_ON ||
+ (cfg.sshbug_hmac2 == BUG_AUTO &&
+ (!strncmp(imp, "2.1.0", 5) || !strncmp(imp, "2.0.", 4) ||
+ !strncmp(imp, "2.2.0", 5) || !strncmp(imp, "2.3.0", 5) ||
+ !strncmp(imp, "2.1 ", 4)))) {
/*
* These versions have the HMAC bug.
*/
ssh_remote_bugs |= BUG_SSH2_HMAC;
logevent("We believe remote version has SSH2 HMAC bug");
}
+
+ if (cfg.sshbug_derivekey2 == BUG_ON ||
+ (cfg.sshbug_derivekey2 == BUG_AUTO &&
+ (!strncmp(imp, "2.0.", 4)))) {
+ /*
+ * These versions have the key-derivation bug (failing to
+ * include the literal shared secret in the hashes that
+ * generate the keys).
+ */
+ ssh_remote_bugs |= BUG_SSH2_DERIVEKEY;
+ logevent("We believe remote version has SSH2 key-derivation bug");
+ }
+
+ if (cfg.sshbug_rsapad2 == BUG_ON ||
+ (cfg.sshbug_rsapad2 == BUG_AUTO &&
+ ((!strncmp(imp, "OpenSSH_2.", 10) && imp[10]>='5' && imp[10]<='9') ||
+ (!strncmp(imp, "OpenSSH_3.", 10) && imp[10]>='0' && imp[10]<='2')))){
+ /*
+ * These versions have the SSH2 RSA padding bug.
+ */
+ ssh_remote_bugs |= BUG_SSH2_RSA_PADDING;
+ logevent("We believe remote version has SSH2 RSA padding bug");
+ }
+
+ if (cfg.sshbug_dhgex2 == BUG_ON) {
+ /*
+ * These versions have the SSH2 DH GEX bug.
+ */
+ ssh_remote_bugs |= BUG_SSH2_DH_GEX;
+ logevent("We believe remote version has SSH2 DH group exchange bug");
+ }
}
static int do_ssh_init(unsigned char c)
{
- static char vslen;
+ static int vslen;
static char version[10];
static char *vstring;
static int vstrsize;
static char *vlog;
static int i;
+ static int proto1, proto2;
crBegin;
crReturn(1); /* get another character */
}
- vstring = smalloc(16);
vstrsize = 16;
+ vstring = smalloc(vstrsize);
strcpy(vstring, "SSH-");
vslen = 4;
i = 0;
vstring[vslen] = 0;
vlog = smalloc(20 + vslen);
+ vstring[strcspn (vstring, "\r\n")] = '\0'; /* remove end-of-line chars */
sprintf(vlog, "Server version: %s", vstring);
- ssh_detect_bugs(vstring);
- vlog[strcspn(vlog, "\r\n")] = '\0';
logevent(vlog);
+ ssh_detect_bugs(vstring);
sfree(vlog);
/*
- * Server version "1.99" means we can choose whether we use v1
- * or v2 protocol. Choice is based on cfg.sshprot.
+ * Decide which SSH protocol version to support.
*/
- if (ssh_versioncmp(version, cfg.sshprot == 1 ? "2.0" : "1.99") >= 0) {
+
+ /* Anything strictly below "2.0" means protocol 1 is supported. */
+ proto1 = ssh_versioncmp(version, "2.0") < 0;
+ /* Anything greater or equal to "1.99" means protocol 2 is supported. */
+ proto2 = ssh_versioncmp(version, "1.99") >= 0;
+
+ if (cfg.sshprot == 0 && !proto1) {
+ bombout(("SSH protocol version 1 required by user but not provided by server"));
+ crReturn(0);
+ }
+ if (cfg.sshprot == 3 && !proto2) {
+ bombout(("SSH protocol version 2 required by user but not provided by server"));
+ crReturn(0);
+ }
+
+ if (proto2 && (cfg.sshprot >= 2 || !proto1)) {
/*
- * This is a v2 server. Begin v2 protocol.
+ * Use v2 protocol.
*/
char verstring[80], vlog[100];
sprintf(verstring, "SSH-2.0-%s", sshver);
s_rdpkt = ssh2_rdpkt;
} else {
/*
- * This is a v1 server. Begin v1 protocol.
+ * Use v1 protocol.
*/
char verstring[80], vlog[100];
sprintf(verstring, "SSH-%s-%s",
sprintf(vlog, "We claim version: %s", verstring);
logevent(vlog);
strcat(verstring, "\n");
+
logevent("Using SSH protocol version 1");
sk_write(s, verstring, strlen(verstring));
ssh_protocol = ssh1_protocol;
while (1) {
while (datalen > 0) {
if (s_rdpkt(&data, &datalen) == 0) {
+ if (ssh_state == SSH_STATE_CLOSED) {
+ return;
+ }
ssh_protocol(NULL, 0, 1);
if (ssh_state == SSH_STATE_CLOSED) {
return;
int calling_back)
{
ssh_state = SSH_STATE_CLOSED;
- sk_close(s);
- s = NULL;
+ if (s) {
+ sk_close(s);
+ s = NULL;
+ }
if (error_msg) {
/* A socket error has occurred. */
+ logevent(error_msg);
connection_fatal(error_msg);
} else {
/* Otherwise, the remote side closed the connection normally. */
return 1;
}
+static void ssh_sent(Plug plug, int bufsize)
+{
+ /*
+ * If the send backlog on the SSH socket itself clears, we
+ * should unthrottle the whole world if it was throttled.
+ */
+ if (bufsize < SSH_MAX_BACKLOG)
+ ssh_throttle_all(0, bufsize);
+}
+
/*
* Connect to specified host and port.
* Returns an error message, or NULL on success.
* Also places the canonical host name into `realhost'. It must be
* freed by the caller.
*/
-static char *connect_to_host(char *host, int port, char **realhost)
+static char *connect_to_host(char *host, int port, char **realhost, int nodelay)
{
static struct plug_function_table fn_table = {
ssh_closing,
- ssh_receive
+ ssh_receive,
+ ssh_sent,
+ NULL
}, *fn_table_ptr = &fn_table;
SockAddr addr;
/*
* Try to find host.
*/
+ {
+ char buf[200];
+ sprintf(buf, "Looking up host \"%.170s\"", host);
+ logevent(buf);
+ }
addr = sk_namelookup(host, realhost);
if ((err = sk_addr_error(addr)))
return err;
/*
* Open socket.
*/
- s = sk_new(addr, port, 0, 1, &fn_table_ptr);
- if ((err = sk_socket_error(s)))
+ {
+ char buf[200], addrbuf[100];
+ sk_getaddr(addr, addrbuf, 100);
+ sprintf(buf, "Connecting to %.100s port %d", addrbuf, port);
+ logevent(buf);
+ }
+ s = new_connection(addr, *realhost, port, 0, 1, nodelay, &fn_table_ptr);
+ if ((err = sk_socket_error(s))) {
+ s = NULL;
return err;
+ }
#ifdef FWHACK
sk_write(s, "connect ", 8);
}
/*
+ * Throttle or unthrottle the SSH connection.
+ */
+static void ssh1_throttle(int adjust)
+{
+ int old_count = ssh1_throttle_count;
+ ssh1_throttle_count += adjust;
+ assert(ssh1_throttle_count >= 0);
+ if (ssh1_throttle_count && !old_count) {
+ sk_set_frozen(s, 1);
+ } else if (!ssh1_throttle_count && old_count) {
+ sk_set_frozen(s, 0);
+ }
+}
+
+/*
+ * Throttle or unthrottle _all_ local data streams (for when sends
+ * on the SSH connection itself back up).
+ */
+static void ssh_throttle_all(int enable, int bufsize)
+{
+ int i;
+ struct ssh_channel *c;
+
+ if (enable == ssh_throttled_all)
+ return;
+ ssh_throttled_all = enable;
+ ssh_overall_bufsize = bufsize;
+ if (!ssh_channels)
+ return;
+ for (i = 0; NULL != (c = index234(ssh_channels, i)); i++) {
+ switch (c->type) {
+ case CHAN_MAINSESSION:
+ /*
+ * This is treated separately, outside the switch.
+ */
+ break;
+ case CHAN_X11:
+ x11_override_throttle(c->u.x11.s, enable);
+ break;
+ case CHAN_AGENT:
+ /* Agent channels require no buffer management. */
+ break;
+ case CHAN_SOCKDATA:
+ pfd_override_throttle(c->u.x11.s, enable);
+ break;
+ }
+ }
+}
+
+/*
+ * Username and password input, abstracted off into reusable
+ * routines (hopefully even reusable between SSH1 and SSH2!).
+ */
+static char *ssh_userpass_input_buffer;
+static int ssh_userpass_input_buflen;
+static int ssh_userpass_input_bufpos;
+static int ssh_userpass_input_echo;
+
+/* Set up a username or password input loop on a given buffer. */
+void setup_userpass_input(char *buffer, int buflen, int echo)
+{
+ ssh_userpass_input_buffer = buffer;
+ ssh_userpass_input_buflen = buflen;
+ ssh_userpass_input_bufpos = 0;
+ ssh_userpass_input_echo = echo;
+}
+
+/*
+ * Process some terminal data in the course of username/password
+ * input. Returns >0 for success (line of input returned in
+ * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
+ * for inconclusive (keep waiting for more input please).
+ */
+int process_userpass_input(unsigned char *in, int inlen)
+{
+ char c;
+
+ while (inlen--) {
+ switch (c = *in++) {
+ case 10:
+ case 13:
+ ssh_userpass_input_buffer[ssh_userpass_input_bufpos] = 0;
+ ssh_userpass_input_buffer[ssh_userpass_input_buflen-1] = 0;
+ return +1;
+ break;
+ case 8:
+ case 127:
+ if (ssh_userpass_input_bufpos > 0) {
+ if (ssh_userpass_input_echo)
+ c_write_str("\b \b");
+ ssh_userpass_input_bufpos--;
+ }
+ break;
+ case 21:
+ case 27:
+ while (ssh_userpass_input_bufpos > 0) {
+ if (ssh_userpass_input_echo)
+ c_write_str("\b \b");
+ ssh_userpass_input_bufpos--;
+ }
+ break;
+ case 3:
+ case 4:
+ return -1;
+ break;
+ default:
+ if (((c >= ' ' && c <= '~') ||
+ ((unsigned char) c >= 160))
+ && ssh_userpass_input_bufpos < ssh_userpass_input_buflen-1) {
+ ssh_userpass_input_buffer[ssh_userpass_input_bufpos++] = c;
+ if (ssh_userpass_input_echo)
+ c_write(&c, 1);
+ }
+ break;
+ }
+ }
+ return 0;
+}
+
+/*
* Handle the key exchange and user authentication phases.
*/
static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
{
- int i, j, len;
- unsigned char *rsabuf, *keystr1, *keystr2;
+ int i, j;
+ static int len;
+ static unsigned char *rsabuf, *keystr1, *keystr2;
unsigned char cookie[8];
struct RSAKey servkey, hostkey;
struct MD5Context md5c;
static unsigned long supported_ciphers_mask, supported_auths_mask;
- static int tried_publickey;
+ static int tried_publickey, tried_agent;
+ static int tis_auth_refused, ccard_auth_refused;
static unsigned char session_id[16];
- int cipher_type;
+ static int cipher_type;
static char username[100];
+ static void *publickey_blob;
+ int publickey_bloblen;
crBegin;
logevent("Encrypted session key");
- switch (cfg.cipher) {
- case CIPHER_BLOWFISH:
- cipher_type = SSH_CIPHER_BLOWFISH;
- break;
- case CIPHER_DES:
- cipher_type = SSH_CIPHER_DES;
- break;
- case CIPHER_3DES:
- cipher_type = SSH_CIPHER_3DES;
- break;
- case CIPHER_AES:
- c_write_str("AES not supported in SSH1, falling back to 3DES\r\n");
- cipher_type = SSH_CIPHER_3DES;
- break;
- }
- if ((supported_ciphers_mask & (1 << cipher_type)) == 0) {
- c_write_str
- ("Selected cipher not supported, falling back to 3DES\r\n");
- cipher_type = SSH_CIPHER_3DES;
- if ((supported_ciphers_mask & (1 << cipher_type)) == 0) {
- bombout(("Server violates SSH 1 protocol by "
- "not supporting 3DES encryption"));
+ {
+ int cipher_chosen = 0, warn = 0;
+ char *cipher_string = NULL;
+ for (i = 0; !cipher_chosen && i < CIPHER_MAX; i++) {
+ int next_cipher = cfg.ssh_cipherlist[i];
+ if (next_cipher == CIPHER_WARN) {
+ /* If/when we choose a cipher, warn about it */
+ warn = 1;
+ } else if (next_cipher == CIPHER_AES) {
+ /* XXX Probably don't need to mention this. */
+ logevent("AES not supported in SSH1, skipping");
+ } else {
+ switch (next_cipher) {
+ case CIPHER_3DES: cipher_type = SSH_CIPHER_3DES;
+ cipher_string = "3DES"; break;
+ case CIPHER_BLOWFISH: cipher_type = SSH_CIPHER_BLOWFISH;
+ cipher_string = "Blowfish"; break;
+ case CIPHER_DES: cipher_type = SSH_CIPHER_DES;
+ cipher_string = "single-DES"; break;
+ }
+ if (supported_ciphers_mask & (1 << cipher_type))
+ cipher_chosen = 1;
+ }
+ }
+ if (!cipher_chosen) {
+ if ((supported_ciphers_mask & (1 << SSH_CIPHER_3DES)) == 0)
+ bombout(("Server violates SSH 1 protocol by not "
+ "supporting 3DES encryption"));
+ else
+ /* shouldn't happen */
+ bombout(("No supported ciphers found"));
crReturn(0);
}
+
+ /* Warn about chosen cipher if necessary. */
+ if (warn)
+ askcipher(cipher_string, 0);
}
+
switch (cipher_type) {
case SSH_CIPHER_3DES:
logevent("Using 3DES encryption");
fflush(stdout);
{
- static int pos = 0;
- static char c;
if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
- if (ssh_get_line) {
+ if (ssh_get_line && !ssh_getline_pw_only) {
if (!ssh_get_line("login as: ",
username, sizeof(username), FALSE)) {
/*
crReturn(1);
}
} else {
+ static int ret;
c_write_str("login as: ");
ssh_send_ok = 1;
- while (pos >= 0) {
+
+ setup_userpass_input(username, sizeof(username), 1);
+ do {
crWaitUntil(!ispkt);
- while (inlen--)
- switch (c = *in++) {
- case 10:
- case 13:
- username[pos] = 0;
- pos = -1;
- break;
- case 8:
- case 127:
- if (pos > 0) {
- c_write_str("\b \b");
- pos--;
- }
- break;
- case 21:
- case 27:
- while (pos > 0) {
- c_write_str("\b \b");
- pos--;
- }
- break;
- case 3:
- case 4:
- random_save_seed();
- exit(0);
- break;
- default:
- if (((c >= ' ' && c <= '~') ||
- ((unsigned char) c >= 160))
- && pos < sizeof(username)-1) {
- username[pos++] = c;
- c_write(&c, 1);
- }
- break;
- }
- }
+ ret = process_userpass_input(in, inlen);
+ } while (ret == 0);
+ if (ret < 0)
+ cleanup_exit(0);
c_write_str("\r\n");
- username[strcspn(username, "\n\r")] = '\0';
}
} else {
- strncpy(username, cfg.username, 99);
- username[99] = '\0';
+ strncpy(username, cfg.username, sizeof(username));
+ username[sizeof(username)-1] = '\0';
}
send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END);
crWaitUntil(ispkt);
- tried_publickey = 0;
+ if ((ssh_remote_bugs & BUG_CHOKES_ON_RSA)) {
+ /* We must not attempt PK auth. Pretend we've already tried it. */
+ tried_publickey = tried_agent = 1;
+ } else {
+ tried_publickey = tried_agent = 0;
+ }
+ tis_auth_refused = ccard_auth_refused = 0;
+ /* Load the public half of cfg.keyfile so we notice if it's in Pageant */
+ if (*cfg.keyfile) {
+ if (!rsakey_pubblob(cfg.keyfile, &publickey_blob, &publickey_bloblen))
+ publickey_blob = NULL;
+ } else
+ publickey_blob = NULL;
while (pktin.type == SSH1_SMSG_FAILURE) {
static char password[100];
static int pos;
static char c;
static int pwpkt_type;
- /*
- * Show password prompt, having first obtained it via a TIS
- * or CryptoCard exchange if we're doing TIS or CryptoCard
- * authentication.
- */
pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
- if (agent_exists()) {
+
+ if (agent_exists() && !tried_agent) {
/*
* Attempt RSA authentication using Pageant.
*/
static int authed = FALSE;
void *r;
+ tried_agent = 1;
logevent("Pageant is running. Requesting keys.");
/* Request the keys held by the agent. */
sprintf(buf, "Trying Pageant key #%d", i);
logevent(buf);
}
+ if (publickey_blob &&
+ !memcmp(p, publickey_blob, publickey_bloblen)) {
+ logevent("This key matches configured key file");
+ tried_publickey = 1;
+ }
p += 4;
p += ssh1_read_bignum(p, &key.exponent);
p += ssh1_read_bignum(p, &key.modulus);
ssh1_read_bignum(pktin.body, &challenge);
{
char *agentreq, *q, *ret;
+ void *vret;
int len, retlen;
len = 1 + 4; /* message type, bit count */
len += ssh1_bignum_length(key.exponent);
memcpy(q, session_id, 16);
q += 16;
PUT_32BIT(q, 1); /* response format */
- agent_query(agentreq, len + 4, &ret, &retlen);
+ agent_query(agentreq, len + 4, &vret, &retlen);
+ ret = vret;
sfree(agentreq);
if (ret) {
if (ret[4] == SSH1_AGENT_RSA_RESPONSE) {
if (*cfg.keyfile && !tried_publickey)
pwpkt_type = SSH1_CMSG_AUTH_RSA;
- if (pktin.type == SSH1_SMSG_FAILURE &&
- cfg.try_tis_auth &&
- (supported_auths_mask & (1 << SSH1_AUTH_TIS))) {
+ if (cfg.try_tis_auth &&
+ (supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
+ !tis_auth_refused) {
pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
logevent("Requested TIS authentication");
send_packet(SSH1_CMSG_AUTH_TIS, PKT_END);
logevent("TIS authentication declined");
if (flags & FLAG_INTERACTIVE)
c_write_str("TIS authentication refused.\r\n");
+ tis_auth_refused = 1;
+ continue;
} else {
int challengelen = ((pktin.body[0] << 24) |
(pktin.body[1] << 16) |
if (challengelen > sizeof(prompt) - 1)
challengelen = sizeof(prompt) - 1; /* prevent overrun */
memcpy(prompt, pktin.body + 4, challengelen);
- prompt[challengelen] = '\0';
+ /* Prompt heuristic comes from OpenSSH */
+ strncpy(prompt + challengelen,
+ memchr(prompt, '\n', challengelen) ?
+ "": "\r\nResponse: ",
+ (sizeof prompt) - challengelen);
+ prompt[(sizeof prompt) - 1] = '\0';
}
}
- if (pktin.type == SSH1_SMSG_FAILURE &&
- cfg.try_tis_auth &&
- (supported_auths_mask & (1 << SSH1_AUTH_CCARD))) {
+ if (cfg.try_tis_auth &&
+ (supported_auths_mask & (1 << SSH1_AUTH_CCARD)) &&
+ !ccard_auth_refused) {
pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
logevent("Requested CryptoCard authentication");
send_packet(SSH1_CMSG_AUTH_CCARD, PKT_END);
if (pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
logevent("CryptoCard authentication declined");
c_write_str("CryptoCard authentication refused.\r\n");
+ ccard_auth_refused = 1;
+ continue;
} else {
int challengelen = ((pktin.body[0] << 24) |
(pktin.body[1] << 16) |
if (challengelen > sizeof(prompt) - 1)
challengelen = sizeof(prompt) - 1; /* prevent overrun */
memcpy(prompt, pktin.body + 4, challengelen);
- strncpy(prompt + challengelen, "\r\nResponse : ",
+ strncpy(prompt + challengelen,
+ memchr(prompt, '\n', challengelen) ?
+ "" : "\r\nResponse: ",
sizeof(prompt) - challengelen);
prompt[sizeof(prompt) - 1] = '\0';
}
}
if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
char *comment = NULL;
+ int type;
+ char msgbuf[256];
if (flags & FLAG_VERBOSE)
c_write_str("Trying public key authentication.\r\n");
+ sprintf(msgbuf, "Trying public key \"%.200s\"", cfg.keyfile);
+ logevent(msgbuf);
+ type = key_type(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(msgbuf);
+ c_write_str("\r\n");
+ tried_publickey = 1;
+ continue;
+ }
if (!rsakey_encrypted(cfg.keyfile, &comment)) {
if (flags & FLAG_VERBOSE)
c_write_str("No passphrase required.\r\n");
sfree(comment);
}
+ /*
+ * Show password prompt, having first obtained it via a TIS
+ * or CryptoCard exchange if we're doing TIS or CryptoCard
+ * authentication.
+ */
if (ssh_get_line) {
if (!ssh_get_line(prompt, password, sizeof(password), TRUE)) {
/*
send_packet(SSH1_MSG_DISCONNECT,
PKT_STR, "No more passwords available to try",
PKT_END);
+ logevent("Unable to authenticate");
connection_fatal("Unable to authenticate");
ssh_state = SSH_STATE_CLOSED;
crReturn(1);
}
} else {
- c_write_str(prompt);
+ /* Prompt may have come from server. We've munged it a bit, so
+ * we know it to be zero-terminated at least once. */
+ static int ret;
+ c_write_untrusted(prompt, strlen(prompt));
pos = 0;
- ssh_send_ok = 1;
- while (pos >= 0) {
+
+ setup_userpass_input(password, sizeof(password), 0);
+ do {
crWaitUntil(!ispkt);
- while (inlen--)
- switch (c = *in++) {
- case 10:
- case 13:
- password[pos] = 0;
- pos = -1;
- break;
- case 8:
- case 127:
- if (pos > 0)
- pos--;
- break;
- case 21:
- case 27:
- pos = 0;
- break;
- case 3:
- case 4:
- random_save_seed();
- exit(0);
- break;
- default:
- if (pos < sizeof(password)-1)
- password[pos++] = c;
- break;
- }
- }
+ ret = process_userpass_input(in, inlen);
+ } while (ret == 0);
+ if (ret < 0)
+ cleanup_exit(0);
c_write_str("\r\n");
}
tried_publickey = 1;
i = loadrsakey(cfg.keyfile, &pubkey, password);
if (i == 0) {
- c_write_str("Couldn't load public key from ");
+ c_write_str("Couldn't load private key from ");
c_write_str(cfg.keyfile);
c_write_str(".\r\n");
continue; /* go and try password */
* use of the fact that the password is interpreted
* as a C string: so we can append a NUL, then some
* random data.
+ *
+ * One server (a Cisco one) can deal with neither
+ * SSH1_MSG_IGNORE _nor_ a padded password string.
+ * For this server we are left with no defences
+ * against password length sniffing.
*/
- if (ssh_remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE) {
- char string[64];
- char *s;
- int len;
-
- len = strlen(password);
- if (len < sizeof(string)) {
- s = string;
- strcpy(string, password);
- len++; /* cover the zero byte */
- while (len < sizeof(string)) {
- string[len++] = (char) random_byte();
- }
- } else {
- s = password;
- }
- send_packet(pwpkt_type, PKT_INT, len,
- PKT_DATA, s, len, PKT_END);
- } else {
+ if (!(ssh_remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
+ /*
+ * The server can deal with SSH1_MSG_IGNORE, so
+ * we can use the primary defence.
+ */
int bottom, top, pwlen, i;
char *randomstr;
PKT_STR, randomstr, PKT_END);
}
}
+ logevent("Sending password with camouflage packets");
ssh_pkt_defersend();
+ }
+ else if (!(ssh_remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
+ /*
+ * The server can't deal with SSH1_MSG_IGNORE
+ * but can deal with padded passwords, so we
+ * can use the secondary defence.
+ */
+ char string[64];
+ char *s;
+ int len;
+
+ len = strlen(password);
+ if (len < sizeof(string)) {
+ s = string;
+ strcpy(string, password);
+ len++; /* cover the zero byte */
+ while (len < sizeof(string)) {
+ string[len++] = (char) random_byte();
+ }
+ } else {
+ s = password;
+ }
+ logevent("Sending length-padded password");
+ send_packet(pwpkt_type, PKT_INT, len,
+ PKT_DATA, s, len, PKT_END);
+ } else {
+ /*
+ * The server has _both_
+ * BUG_CHOKES_ON_SSH1_IGNORE and
+ * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
+ * therefore nothing we can do.
+ */
+ int len;
+ len = strlen(password);
+ logevent("Sending unpadded password");
+ send_packet(pwpkt_type, PKT_INT, len,
+ PKT_DATA, password, len, PKT_END);
}
} else {
send_packet(pwpkt_type, PKT_STR, password, PKT_END);
void sshfwd_close(struct ssh_channel *c)
{
if (c && !c->closes) {
- if (ssh_version == 1) {
- send_packet(SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
- PKT_END);
- } else {
- ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
- ssh2_pkt_adduint32(c->remoteid);
- ssh2_pkt_send();
+ /*
+ * If the channel's remoteid is -1, 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 (ssh_version == 1) {
+ send_packet(SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
+ PKT_END);
+ } else {
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
+ ssh2_pkt_adduint32(c->remoteid);
+ ssh2_pkt_send();
+ }
}
- c->closes = 1;
+ c->closes = 1; /* sent MSG_CLOSE */
if (c->type == CHAN_X11) {
c->u.x11.s = NULL;
- logevent("X11 connection terminated");
+ logevent("Forwarded X11 connection terminated");
+ } else if (c->type == CHAN_SOCKDATA ||
+ c->type == CHAN_SOCKDATA_DORMANT) {
+ c->u.pfd.s = NULL;
+ logevent("Forwarded port closed");
}
}
}
-void sshfwd_write(struct ssh_channel *c, char *buf, int len)
+int sshfwd_write(struct ssh_channel *c, char *buf, int len)
{
if (ssh_version == 1) {
send_packet(SSH1_MSG_CHANNEL_DATA,
PKT_INT, c->remoteid,
PKT_INT, len, PKT_DATA, buf, len, PKT_END);
+ /*
+ * In SSH1 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
+ * _everything_ will be throttled as a whole.
+ */
+ return 0;
} else {
ssh2_add_channel_data(c, buf, len);
- ssh2_try_send(c);
+ return ssh2_try_send(c);
+ }
+}
+
+void sshfwd_unthrottle(struct ssh_channel *c, int bufsize)
+{
+ if (ssh_version == 1) {
+ if (c->v.v1.throttling && bufsize < SSH1_BUFFER_LIMIT) {
+ c->v.v1.throttling = 0;
+ ssh1_throttle(-1);
+ }
+ } else {
+ ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
}
}
}
}
+ {
+ char type;
+ static char *e;
+ int n;
+ int sport,dport,sserv,dserv;
+ char sports[256], dports[256], host[256];
+ char buf[1024];
+ struct servent *se;
+
+ ssh_rportfwds = newtree234(ssh_rportcmp_ssh1);
+ /* Add port forwardings. */
+ e = cfg.portfwd;
+ while (*e) {
+ type = *e++;
+ n = 0;
+ while (*e && *e != '\t')
+ sports[n++] = *e++;
+ sports[n] = 0;
+ if (*e == '\t')
+ e++;
+ n = 0;
+ while (*e && *e != ':')
+ host[n++] = *e++;
+ host[n] = 0;
+ if (*e == ':')
+ e++;
+ n = 0;
+ while (*e)
+ dports[n++] = *e++;
+ dports[n] = 0;
+ e++;
+ dport = atoi(dports);
+ dserv = 0;
+ if (dport == 0) {
+ dserv = 1;
+ se = getservbyname(dports, NULL);
+ if (se != NULL) {
+ dport = ntohs(se->s_port);
+ } else {
+ sprintf(buf,
+ "Service lookup failed for destination port \"%s\"",
+ dports);
+ logevent(buf);
+ }
+ }
+ sport = atoi(sports);
+ sserv = 0;
+ if (sport == 0) {
+ sserv = 1;
+ se = getservbyname(sports, NULL);
+ if (se != NULL) {
+ sport = ntohs(se->s_port);
+ } else {
+ sprintf(buf,
+ "Service lookup failed for source port \"%s\"",
+ sports);
+ logevent(buf);
+ }
+ }
+ if (sport && dport) {
+ if (type == 'L') {
+ pfd_addforward(host, dport, sport);
+ sprintf(buf, "Local port %.*s%.*s%d%.*s forwarding to"
+ " %s:%.*s%.*s%d%.*s",
+ sserv ? strlen(sports) : 0, sports,
+ sserv, "(", sport, sserv, ")",
+ host,
+ dserv ? strlen(dports) : 0, dports,
+ dserv, "(", dport, dserv, ")");
+ logevent(buf);
+ } else {
+ struct ssh_rportfwd *pf;
+ pf = smalloc(sizeof(*pf));
+ strcpy(pf->dhost, host);
+ pf->dport = dport;
+ if (add234(ssh_rportfwds, pf) != pf) {
+ sprintf(buf,
+ "Duplicate remote port forwarding to %s:%d",
+ host, dport);
+ logevent(buf);
+ sfree(pf);
+ } else {
+ sprintf(buf, "Requesting remote port %.*s%.*s%d%.*s"
+ " forward to %s:%.*s%.*s%d%.*s",
+ sserv ? strlen(sports) : 0, sports,
+ sserv, "(", sport, sserv, ")",
+ host,
+ dserv ? strlen(dports) : 0, dports,
+ dserv, "(", dport, dserv, ")");
+ logevent(buf);
+ send_packet(SSH1_CMSG_PORT_FORWARD_REQUEST,
+ PKT_INT, sport,
+ PKT_STR, host,
+ PKT_INT, dport,
+ PKT_END);
+ do {
+ crReturnV;
+ } while (!ispkt);
+ if (pktin.type != SSH1_SMSG_SUCCESS
+ && pktin.type != SSH1_SMSG_FAILURE) {
+ bombout(("Protocol confusion"));
+ crReturnV;
+ } else if (pktin.type == SSH1_SMSG_FAILURE) {
+ c_write_str("Server refused port forwarding\r\n");
+ ssh_editing = ssh_echoing = 1;
+ }
+ logevent("Remote port forwarding enabled");
+ }
+ }
+ }
+ }
+ }
+
if (!cfg.nopty) {
send_packet(SSH1_CMSG_REQUEST_PTY,
PKT_STR, cfg.termtype,
- PKT_INT, rows, PKT_INT, cols,
+ PKT_INT, term ? term->rows : 24,
+ PKT_INT, term ? term->cols : 80,
PKT_INT, 0, PKT_INT, 0, PKT_CHAR, 0, PKT_END);
ssh_state = SSH_STATE_INTERMED;
do {
zlib_decompress_init();
}
- if (*cfg.remote_cmd_ptr)
- send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cfg.remote_cmd_ptr,
- PKT_END);
- else
- send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END);
- logevent("Started session");
+ /*
+ * Start the shell or command.
+ *
+ * Special case: if the first-choice command is an SSH2
+ * subsystem (hence not usable here) and the second choice
+ * exists, we fall straight back to that.
+ */
+ {
+ char *cmd = cfg.remote_cmd_ptr;
+
+ if (cfg.ssh_subsys && cfg.remote_cmd_ptr2) {
+ cmd = cfg.remote_cmd_ptr2;
+ ssh_fallback_cmd = TRUE;
+ }
+ if (*cmd)
+ send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
+ else
+ send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END);
+ logevent("Started session");
+ }
ssh_state = SSH_STATE_SESSION;
if (size_needed)
if (eof_needed)
ssh_special(TS_EOF);
- ldisc_send(NULL, 0); /* cause ldisc to notice changes */
+ ldisc_send(NULL, 0, 0); /* cause ldisc to notice changes */
ssh_send_ok = 1;
ssh_channels = newtree234(ssh_channelcmp);
while (1) {
if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
pktin.type == SSH1_SMSG_STDERR_DATA) {
long len = GET_32BIT(pktin.body);
- from_backend(pktin.type == SSH1_SMSG_STDERR_DATA,
- pktin.body + 4, len);
+ int bufsize =
+ from_backend(frontend, pktin.type == SSH1_SMSG_STDERR_DATA,
+ pktin.body + 4, len);
+ if (!ssh1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
+ ssh1_stdout_throttling = 1;
+ ssh1_throttle(+1);
+ }
} else if (pktin.type == SSH1_MSG_DISCONNECT) {
ssh_state = SSH_STATE_CLOSED;
logevent("Received disconnect request");
c->remoteid = GET_32BIT(pktin.body);
c->localid = alloc_channel_id();
c->closes = 0;
+ c->v.v1.throttling = 0;
c->type = CHAN_X11; /* identify channel type */
add234(ssh_channels, c);
send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
c->remoteid = GET_32BIT(pktin.body);
c->localid = alloc_channel_id();
c->closes = 0;
+ c->v.v1.throttling = 0;
c->type = CHAN_AGENT; /* identify channel type */
c->u.a.lensofar = 0;
add234(ssh_channels, c);
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 hostsize, port;
+ char host[256], buf[1024];
+ char *p, *h, *e;
+ c = smalloc(sizeof(struct ssh_channel));
+
+ hostsize = GET_32BIT(pktin.body+4);
+ for(h = host, p = pktin.body+8; hostsize != 0; hostsize--) {
+ if (h+1 < host+sizeof(host))
+ *h++ = *p;
+ p++;
+ }
+ *h = 0;
+ port = GET_32BIT(p);
+
+ strcpy(pf.dhost, host);
+ pf.dport = port;
+
+ if (find234(ssh_rportfwds, &pf, NULL) == NULL) {
+ sprintf(buf, "Rejected remote port open request for %s:%d",
+ host, port);
+ logevent(buf);
+ send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE,
+ PKT_INT, GET_32BIT(pktin.body), PKT_END);
+ } else {
+ sprintf(buf, "Received remote port open request for %s:%d",
+ host, port);
+ logevent(buf);
+ e = pfd_newconnect(&c->u.pfd.s, host, port, c);
+ if (e != NULL) {
+ char buf[256];
+ sprintf(buf, "Port open failed: %s", e);
+ logevent(buf);
+ sfree(c);
+ send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE,
+ PKT_INT, GET_32BIT(pktin.body),
+ PKT_END);
+ } else {
+ c->remoteid = GET_32BIT(pktin.body);
+ c->localid = alloc_channel_id();
+ c->closes = 0;
+ c->v.v1.throttling = 0;
+ c->type = CHAN_SOCKDATA; /* identify channel type */
+ add234(ssh_channels, c);
+ send_packet(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 = GET_32BIT(pktin.body);
+ unsigned int localid = GET_32BIT(pktin.body+4);
+ 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(SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
+ PKT_END);
+ }
+
+ } else if (pktin.type == SSH1_MSG_CHANNEL_OPEN_FAILURE) {
+ unsigned int remoteid = GET_32BIT(pktin.body);
+ unsigned int localid = GET_32BIT(pktin.body+4);
+ 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 = GET_32BIT(pktin.body);
struct ssh_channel *c;
c = find234(ssh_channels, &i, ssh_channelfind);
- if (c) {
+ if (c && ((int)c->remoteid) != -1) {
int closetype;
closetype =
(pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
- if (!(c->closes & closetype))
- send_packet(pktin.type, PKT_INT, c->remoteid,
- PKT_END);
+
if ((c->closes == 0) && (c->type == CHAN_X11)) {
- logevent("X11 connection closed");
+ logevent("Forwarded X11 connection terminated");
assert(c->u.x11.s != NULL);
x11_close(c->u.x11.s);
c->u.x11.s = NULL;
}
- c->closes |= closetype;
- if (c->closes == 3) {
+ 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(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));
}
} else if (pktin.type == SSH1_MSG_CHANNEL_DATA) {
/* Data sent down one of our channels. */
struct ssh_channel *c;
c = find234(ssh_channels, &i, ssh_channelfind);
if (c) {
+ int bufsize;
switch (c->type) {
case CHAN_X11:
- x11_send(c->u.x11.s, p, len);
+ 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. */
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(+1);
+ }
}
} else if (pktin.type == SSH1_SMSG_SUCCESS) {
/* may be from EXEC_SHELL on some servers */
/* 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 = GET_32BIT(pktin.body);
+ sprintf(buf, "Server sent command exit status %d",
+ ssh_exitcode);
+ logevent(buf);
send_packet(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_state = SSH_STATE_CLOSED;
+ crReturnV;
} else {
bombout(("Strange packet received: type %d", pktin.type));
crReturnV;
SHA_State s;
/* First 20 bytes. */
SHA_Init(&s);
- sha_mpint(&s, K);
+ if (!(ssh_remote_bugs & BUG_SSH2_DERIVEKEY))
+ sha_mpint(&s, K);
SHA_Bytes(&s, H, 20);
SHA_Bytes(&s, &chr, 1);
SHA_Bytes(&s, sessid, 20);
SHA_Final(&s, keyspace);
/* Next 20 bytes. */
SHA_Init(&s);
- sha_mpint(&s, K);
+ if (!(ssh_remote_bugs & BUG_SSH2_DERIVEKEY))
+ sha_mpint(&s, K);
SHA_Bytes(&s, H, 20);
SHA_Bytes(&s, keyspace, 20);
SHA_Final(&s, keyspace + 20);
*/
static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt)
{
- static int i, j, len, nbits, pbits;
+ static int i, j, len, nbits, pbits, warn;
static char *str;
static Bignum p, g, e, f, K;
static int kex_init_value, kex_reply_value;
static void *hkey; /* actual host key */
static unsigned char exchange_hash[20];
static unsigned char keyspace[40];
- static const struct ssh2_ciphers *preferred_cipher;
+ static int n_preferred_ciphers;
+ static const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
static const struct ssh_compress *preferred_comp;
+ static int cipherstr_started;
static int first_kex;
crBegin;
first_kex = 1;
/*
- * Set up the preferred cipher and compression.
+ * Set up the preferred ciphers. (NULL => warn below here)
*/
- if (cfg.cipher == CIPHER_BLOWFISH) {
- preferred_cipher = &ssh2_blowfish;
- } else if (cfg.cipher == CIPHER_DES) {
- logevent("Single DES not supported in SSH2; using 3DES");
- preferred_cipher = &ssh2_3des;
- } else if (cfg.cipher == CIPHER_3DES) {
- preferred_cipher = &ssh2_3des;
- } else if (cfg.cipher == CIPHER_AES) {
- preferred_cipher = &ssh2_aes;
- } else {
- /* Shouldn't happen, but we do want to initialise to _something_. */
- preferred_cipher = &ssh2_3des;
+ n_preferred_ciphers = 0;
+ for (i = 0; i < CIPHER_MAX; i++) {
+ switch (cfg.ssh_cipherlist[i]) {
+ case CIPHER_BLOWFISH:
+ preferred_ciphers[n_preferred_ciphers] = &ssh2_blowfish;
+ n_preferred_ciphers++;
+ break;
+ case CIPHER_DES:
+ if (cfg.ssh2_des_cbc) {
+ preferred_ciphers[n_preferred_ciphers] = &ssh2_des;
+ n_preferred_ciphers++;
+ }
+ break;
+ case CIPHER_3DES:
+ preferred_ciphers[n_preferred_ciphers] = &ssh2_3des;
+ n_preferred_ciphers++;
+ break;
+ case CIPHER_AES:
+ preferred_ciphers[n_preferred_ciphers] = &ssh2_aes;
+ n_preferred_ciphers++;
+ break;
+ case CIPHER_WARN:
+ /* Flag for later. Don't bother if it's the last in
+ * the list. */
+ if (i < CIPHER_MAX - 1) {
+ preferred_ciphers[n_preferred_ciphers] = NULL;
+ n_preferred_ciphers++;
+ }
+ break;
+ }
}
+
+ /*
+ * Set up preferred compression.
+ */
if (cfg.compression)
preferred_comp = &ssh_zlib;
else
/*
* Be prepared to work around the buggy MAC problem.
*/
- if (cfg.buggymac || (ssh_remote_bugs & BUG_SSH2_HMAC))
+ if (ssh_remote_bugs & BUG_SSH2_HMAC)
maclist = buggymacs, nmacs = lenof(buggymacs);
else
maclist = macs, nmacs = lenof(macs);
/* List key exchange algorithms. */
ssh2_pkt_addstring_start();
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(kex_algs[i]->name);
if (i < lenof(kex_algs) - 1)
ssh2_pkt_addstring_str(",");
}
/* List client->server encryption algorithms. */
ssh2_pkt_addstring_start();
- for (i = 0; i < lenof(ciphers) + 1; i++) {
- const struct ssh2_ciphers *c =
- i == 0 ? preferred_cipher : ciphers[i - 1];
+ cipherstr_started = 0;
+ for (i = 0; i < n_preferred_ciphers; i++) {
+ const struct ssh2_ciphers *c = preferred_ciphers[i];
+ if (!c) continue; /* warning flag */
for (j = 0; j < c->nciphers; j++) {
- ssh2_pkt_addstring_str(c->list[j]->name);
- if (i < lenof(ciphers) || j < c->nciphers - 1)
+ if (cipherstr_started)
ssh2_pkt_addstring_str(",");
+ ssh2_pkt_addstring_str(c->list[j]->name);
+ cipherstr_started = 1;
}
}
/* List server->client encryption algorithms. */
ssh2_pkt_addstring_start();
- for (i = 0; i < lenof(ciphers) + 1; i++) {
- const struct ssh2_ciphers *c =
- i == 0 ? preferred_cipher : ciphers[i - 1];
+ cipherstr_started = 0;
+ for (i = 0; i < n_preferred_ciphers; i++) {
+ const struct ssh2_ciphers *c = preferred_ciphers[i];
+ if (!c) continue; /* warning flag */
for (j = 0; j < c->nciphers; j++) {
- ssh2_pkt_addstring_str(c->list[j]->name);
- if (i < lenof(ciphers) || j < c->nciphers - 1)
+ if (cipherstr_started)
ssh2_pkt_addstring_str(",");
+ ssh2_pkt_addstring_str(c->list[j]->name);
+ cipherstr_started = 1;
}
}
/* List client->server MAC algorithms. */
pktin.savedpos += 16; /* skip garbage cookie */
ssh2_pkt_getstring(&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)) {
kex = kex_algs[i];
break;
}
}
ssh2_pkt_getstring(&str, &len); /* client->server cipher */
- for (i = 0; i < lenof(ciphers) + 1; i++) {
- const struct ssh2_ciphers *c =
- i == 0 ? preferred_cipher : ciphers[i - 1];
- for (j = 0; j < c->nciphers; j++) {
- if (in_commasep_string(c->list[j]->name, str, len)) {
- cscipher_tobe = c->list[j];
- break;
+ warn = 0;
+ for (i = 0; i < n_preferred_ciphers; i++) {
+ const struct ssh2_ciphers *c = preferred_ciphers[i];
+ if (!c) {
+ warn = 1;
+ } else {
+ for (j = 0; j < c->nciphers; j++) {
+ if (in_commasep_string(c->list[j]->name, str, len)) {
+ cscipher_tobe = c->list[j];
+ break;
+ }
}
}
- if (cscipher_tobe)
+ if (cscipher_tobe) {
+ if (warn)
+ askcipher(cscipher_tobe->name, 1);
break;
+ }
+ }
+ if (!cscipher_tobe) {
+ bombout(("Couldn't agree a client-to-server cipher (available: %s)", str));
+ crReturn(0);
}
+
ssh2_pkt_getstring(&str, &len); /* server->client cipher */
- for (i = 0; i < lenof(ciphers) + 1; i++) {
- const struct ssh2_ciphers *c =
- i == 0 ? preferred_cipher : ciphers[i - 1];
- for (j = 0; j < c->nciphers; j++) {
- if (in_commasep_string(c->list[j]->name, str, len)) {
- sccipher_tobe = c->list[j];
- break;
+ warn = 0;
+ for (i = 0; i < n_preferred_ciphers; i++) {
+ const struct ssh2_ciphers *c = preferred_ciphers[i];
+ if (!c) {
+ warn = 1;
+ } else {
+ for (j = 0; j < c->nciphers; j++) {
+ if (in_commasep_string(c->list[j]->name, str, len)) {
+ sccipher_tobe = c->list[j];
+ break;
+ }
}
}
- if (sccipher_tobe)
+ if (sccipher_tobe) {
+ if (warn)
+ askcipher(sccipher_tobe->name, 2);
break;
+ }
}
+ if (!sccipher_tobe) {
+ bombout(("Couldn't agree a server-to-client cipher (available: %s)", str));
+ crReturn(0);
+ }
+
ssh2_pkt_getstring(&str, &len); /* client->server mac */
for (i = 0; i < nmacs; i++) {
if (in_commasep_string(maclist[i]->name, str, len)) {
*/
if (kex == &ssh_diffiehellman_gex) {
logevent("Doing Diffie-Hellman group exchange");
+ ssh_pkt_ctx |= SSH2_PKTCTX_DHGEX;
/*
* Work out how big a DH group we will need to allow that
* much data.
kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
} else {
+ ssh_pkt_ctx |= SSH2_PKTCTX_DHGROUP1;
dh_setup_group1();
kex_init_value = SSH2_MSG_KEXDH_INIT;
kex_reply_value = SSH2_MSG_KEXDH_REPLY;
#endif
hkey = hostkey->newkey(hostkeydata, hostkeylen);
- if (!hostkey->verifysig(hkey, sigdata, siglen, exchange_hash, 20)) {
- bombout(("Server failed host key check"));
- crReturn(0);
- }
-
- /*
- * Expect SSH2_MSG_NEWKEYS from server.
- */
- crWaitUntil(ispkt);
- if (pktin.type != SSH2_MSG_NEWKEYS) {
- bombout(("expected new-keys packet from server"));
+ if (!hkey ||
+ !hostkey->verifysig(hkey, sigdata, siglen, exchange_hash, 20)) {
+ bombout(("Server's host key did not match the signature supplied"));
crReturn(0);
}
ssh2_pkt_send();
/*
+ * Expect SSH2_MSG_NEWKEYS from server.
+ */
+ crWaitUntil(ispkt);
+ if (pktin.type != SSH2_MSG_NEWKEYS) {
+ bombout(("expected new-keys packet from server"));
+ crReturn(0);
+ }
+
+ /*
* Create and initialise session keys.
*/
cscipher = cscipher_tobe;
static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
int len)
{
- if (c->v2.outbufsize < c->v2.outbuflen + len) {
- c->v2.outbufsize = c->v2.outbuflen + len + 1024;
- c->v2.outbuffer = srealloc(c->v2.outbuffer, c->v2.outbufsize);
- }
- memcpy(c->v2.outbuffer + c->v2.outbuflen, buf, len);
- c->v2.outbuflen += len;
+ bufchain_add(&c->v.v2.outbuffer, buf, len);
}
/*
* Attempt to send data on an SSH2 channel.
*/
-static void ssh2_try_send(struct ssh_channel *c)
+static int ssh2_try_send(struct ssh_channel *c)
{
- while (c->v2.remwindow > 0 && c->v2.outbuflen > 0) {
- unsigned len = c->v2.remwindow;
- if (len > c->v2.outbuflen)
- len = c->v2.outbuflen;
- if (len > c->v2.remmaxpkt)
- len = c->v2.remmaxpkt;
+ while (c->v.v2.remwindow > 0 && bufchain_size(&c->v.v2.outbuffer) > 0) {
+ int len;
+ void *data;
+ bufchain_prefix(&c->v.v2.outbuffer, &data, &len);
+ if ((unsigned)len > c->v.v2.remwindow)
+ len = c->v.v2.remwindow;
+ if ((unsigned)len > c->v.v2.remmaxpkt)
+ len = c->v.v2.remmaxpkt;
ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
ssh2_pkt_adduint32(c->remoteid);
ssh2_pkt_addstring_start();
- ssh2_pkt_addstring_data(c->v2.outbuffer, len);
+ ssh2_pkt_addstring_data(data, len);
+ ssh2_pkt_send();
+ bufchain_consume(&c->v.v2.outbuffer, len);
+ c->v.v2.remwindow -= len;
+ }
+
+ /*
+ * After having sent as much data as we can, return the amount
+ * still buffered.
+ */
+ return bufchain_size(&c->v.v2.outbuffer);
+}
+
+/*
+ * Potentially enlarge the window on an SSH2 channel.
+ */
+static void ssh2_set_window(struct ssh_channel *c, unsigned newwin)
+{
+ /*
+ * Never send WINDOW_ADJUST for a channel that the remote side
+ * already thinks it's closed; there's no point, since it won't
+ * be sending any more data anyway.
+ */
+ if (c->closes != 0)
+ return;
+
+ if (newwin > c->v.v2.locwindow) {
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
+ ssh2_pkt_adduint32(c->remoteid);
+ ssh2_pkt_adduint32(newwin - c->v.v2.locwindow);
ssh2_pkt_send();
- c->v2.outbuflen -= len;
- memmove(c->v2.outbuffer, c->v2.outbuffer + len, c->v2.outbuflen);
- c->v2.remwindow -= len;
+ c->v.v2.locwindow = newwin;
}
}
*/
static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
{
- static unsigned long remote_winsize;
- static unsigned long remote_maxpkt;
static enum {
AUTH_INVALID, AUTH_PUBLICKEY_AGENT, AUTH_PUBLICKEY_FILE,
- AUTH_PASSWORD
+ AUTH_PASSWORD,
+ AUTH_KEYBOARD_INTERACTIVE
} method;
static enum {
AUTH_TYPE_NONE,
AUTH_TYPE_PUBLICKEY,
AUTH_TYPE_PUBLICKEY_OFFER_LOUD,
AUTH_TYPE_PUBLICKEY_OFFER_QUIET,
- AUTH_TYPE_PASSWORD
+ AUTH_TYPE_PASSWORD,
+ AUTH_TYPE_KEYBOARD_INTERACTIVE,
+ AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
} type;
- static int gotit, need_pw, can_pubkey, can_passwd;
- static int tried_pubkey_config, tried_agent;
+ static int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
+ static int tried_pubkey_config, tried_agent, tried_keyb_inter;
+ static int kbd_inter_running;
static int we_are_in;
+ static int num_prompts, curr_prompt, echo;
static char username[100];
+ static int got_username;
static char pwprompt[200];
static char password[100];
+ static void *publickey_blob;
+ static int publickey_bloblen;
crBegin;
* the username they will want to be able to get back and
* retype it!
*/
+ username[0] = '\0';
+ got_username = FALSE;
do {
- static int pos;
- static char c;
-
/*
* Get a username.
*/
- pos = 0;
- if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
- if (ssh_get_line) {
+ if (got_username && !cfg.change_username) {
+ /*
+ * We got a username last time round this loop, and
+ * with change_username turned off we don't try to get
+ * it again.
+ */
+ } else if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
+ if (ssh_get_line && !ssh_getline_pw_only) {
if (!ssh_get_line("login as: ",
username, sizeof(username), FALSE)) {
/*
crReturnV;
}
} else {
+ static int ret;
c_write_str("login as: ");
ssh_send_ok = 1;
- while (pos >= 0) {
+ setup_userpass_input(username, sizeof(username), 1);
+ do {
crWaitUntilV(!ispkt);
- while (inlen--)
- switch (c = *in++) {
- case 10:
- case 13:
- username[pos] = 0;
- pos = -1;
- break;
- case 8:
- case 127:
- if (pos > 0) {
- c_write_str("\b \b");
- pos--;
- }
- break;
- case 21:
- case 27:
- while (pos > 0) {
- c_write_str("\b \b");
- pos--;
- }
- break;
- case 3:
- case 4:
- random_save_seed();
- exit(0);
- break;
- default:
- if (((c >= ' ' && c <= '~') ||
- ((unsigned char) c >= 160))
- && pos < sizeof(username)-1) {
- username[pos++] = c;
- c_write(&c, 1);
- }
- break;
- }
- }
+ ret = process_userpass_input(in, inlen);
+ } while (ret == 0);
+ if (ret < 0)
+ cleanup_exit(0);
}
c_write_str("\r\n");
username[strcspn(username, "\n\r")] = '\0';
} else {
char stuff[200];
- strncpy(username, cfg.username, 99);
- username[99] = '\0';
+ strncpy(username, cfg.username, sizeof(username));
+ username[sizeof(username)-1] = '\0';
if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
sprintf(stuff, "Using username \"%s\".\r\n", username);
c_write_str(stuff);
}
}
+ got_username = TRUE;
/*
* Send an authentication request using method "none": (a)
* just in case it succeeds, and (b) so that we know what
* authentication methods we can usefully try next.
*/
+ ssh_pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
+
ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
ssh2_pkt_addstring(username);
ssh2_pkt_addstring("ssh-connection"); /* service requested */
tried_pubkey_config = FALSE;
tried_agent = FALSE;
+ tried_keyb_inter = FALSE;
+ kbd_inter_running = FALSE;
+ /* Load the pub half of cfg.keyfile so we notice if it's in Pageant */
+ if (*cfg.keyfile) {
+ int keytype;
+ logeventf("Reading private key file \"%.150s\"", cfg.keyfile);
+ keytype = key_type(cfg.keyfile);
+ if (keytype == SSH_KEYTYPE_SSH2)
+ publickey_blob = ssh2_userkey_loadpub(cfg.keyfile, NULL,
+ &publickey_bloblen);
+ else {
+ char msgbuf[256];
+ logeventf("Unable to use this key file (%s)",
+ key_type_to_str(keytype));
+ sprintf(msgbuf, "Unable to use key file \"%.150s\" (%s)\r\n",
+ cfg.keyfile, key_type_to_str(keytype));
+ c_write_str(msgbuf);
+ publickey_blob = NULL;
+ }
+ } else
+ publickey_blob = NULL;
while (1) {
/*
break;
}
- if (pktin.type != SSH2_MSG_USERAUTH_FAILURE) {
- bombout(
- ("Strange packet received during authentication: type %d",
+ if (kbd_inter_running &&
+ pktin.type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
+ /*
+ * This is either a further set-of-prompts packet
+ * in keyboard-interactive authentication, or it's
+ * the same one and we came back here with `gotit'
+ * set. In the former case, we must reset the
+ * curr_prompt variable.
+ */
+ if (!gotit)
+ curr_prompt = 0;
+ } else if (pktin.type != SSH2_MSG_USERAUTH_FAILURE) {
+ bombout(("Strange packet received during authentication: type %d",
pktin.type));
crReturnV;
}
* we can look at the string in it and know what we can
* helpfully try next.
*/
- {
+ if (pktin.type == SSH2_MSG_USERAUTH_FAILURE) {
char *methods;
int methlen;
ssh2_pkt_getstring(&methods, &methlen);
+ kbd_inter_running = FALSE;
if (!ssh2_pkt_getbool()) {
/*
* We have received an unequivocal Access
if (type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD)
c_write_str("Server refused our key\r\n");
logevent("Server refused public key");
+ } else if (type == AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET) {
+ /* server declined keyboard-interactive; ignore */
} else {
c_write_str("Access denied\r\n");
logevent("Access denied");
in_commasep_string("publickey", methods, methlen);
can_passwd =
in_commasep_string("password", methods, methlen);
+ can_keyb_inter = cfg.try_ki_auth &&
+ in_commasep_string("keyboard-interactive", methods, methlen);
}
method = 0;
+ ssh_pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
- if (!method && can_pubkey && agent_exists() && !tried_agent) {
- /*
+ /*
+ * Most password/passphrase prompts will be
+ * non-echoing, so we set this to 0 by default.
+ * Exception is that some keyboard-interactive prompts
+ * can be echoing, in which case we'll set this to 1.
+ */
+ echo = 0;
+
+ if (!method && can_pubkey && agent_exists() && !tried_agent) {
+ /*
* Attempt public-key authentication using Pageant.
*/
static unsigned char request[5], *response, *p;
static int authed = FALSE;
void *r;
+ ssh_pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
+ ssh_pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
+
tried_agent = TRUE;
logevent("Pageant is running. Requesting keys.");
static int pklen, alglen, commentlen;
static int siglen, retlen, len;
static char *q, *agentreq, *ret;
+ void *vret;
{
char buf[64];
}
pklen = GET_32BIT(p);
p += 4;
+ if (publickey_blob &&
+ pklen == publickey_bloblen &&
+ !memcmp(p, publickey_blob, publickey_bloblen)) {
+ logevent("This key matches configured key file");
+ tried_pubkey_config = 1;
+ }
pkblob = p;
p += pklen;
alglen = GET_32BIT(pkblob);
q += pktout.length - 5;
/* And finally the (zero) flags word. */
PUT_32BIT(q, 0);
- agent_query(agentreq, len + 4, &ret, &retlen);
+ agent_query(agentreq, len + 4, &vret, &retlen);
+ ret = vret;
sfree(agentreq);
if (ret) {
if (ret[4] == SSH2_AGENT_SIGN_RESPONSE) {
logevent("Sending Pageant's response");
- ssh2_pkt_addstring_start();
- ssh2_pkt_addstring_data(ret + 9,
- GET_32BIT(ret +
- 5));
+ ssh2_add_sigblob(pkblob, pklen,
+ ret + 9, GET_32BIT(ret + 5));
ssh2_pkt_send();
authed = TRUE;
break;
}
}
- if (!method && can_pubkey && *cfg.keyfile
+ if (!method && can_pubkey && publickey_blob
&& !tried_pubkey_config) {
unsigned char *pub_blob;
char *algorithm, *comment;
tried_pubkey_config = TRUE;
+ ssh_pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
+ ssh_pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
+
/*
* Try the public key supplied in the configuration.
*
}
}
+ if (!method && can_keyb_inter && !tried_keyb_inter) {
+ method = AUTH_KEYBOARD_INTERACTIVE;
+ type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
+ tried_keyb_inter = TRUE;
+
+ ssh_pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
+ ssh_pkt_ctx |= SSH2_PKTCTX_KBDINTER;
+
+ ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
+ ssh2_pkt_addstring(username);
+ ssh2_pkt_addstring("ssh-connection"); /* service requested */
+ ssh2_pkt_addstring("keyboard-interactive"); /* method */
+ ssh2_pkt_addstring(""); /* lang */
+ ssh2_pkt_addstring("");
+ ssh2_pkt_send();
+
+ crWaitUntilV(ispkt);
+ if (pktin.type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
+ if (pktin.type == SSH2_MSG_USERAUTH_FAILURE)
+ gotit = TRUE;
+ logevent("Keyboard-interactive authentication refused");
+ type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
+ continue;
+ }
+
+ kbd_inter_running = TRUE;
+ curr_prompt = 0;
+ }
+
+ if (kbd_inter_running) {
+ method = AUTH_KEYBOARD_INTERACTIVE;
+ type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
+ tried_keyb_inter = TRUE;
+
+ ssh_pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
+ ssh_pkt_ctx |= SSH2_PKTCTX_KBDINTER;
+
+ if (curr_prompt == 0) {
+ /*
+ * We've got a fresh USERAUTH_INFO_REQUEST.
+ * Display header data, and start going through
+ * the prompts.
+ */
+ char *name, *inst, *lang;
+ int name_len, inst_len, lang_len;
+
+ ssh2_pkt_getstring(&name, &name_len);
+ ssh2_pkt_getstring(&inst, &inst_len);
+ ssh2_pkt_getstring(&lang, &lang_len);
+ if (name_len > 0) {
+ c_write_untrusted(name, name_len);
+ c_write_str("\r\n");
+ }
+ if (inst_len > 0) {
+ c_write_untrusted(inst, inst_len);
+ c_write_str("\r\n");
+ }
+ num_prompts = ssh2_pkt_getuint32();
+ }
+
+ /*
+ * If there are prompts remaining in the packet,
+ * display one and get a response.
+ */
+ if (curr_prompt < num_prompts) {
+ char *prompt;
+ int prompt_len;
+
+ ssh2_pkt_getstring(&prompt, &prompt_len);
+ if (prompt_len > 0) {
+ strncpy(pwprompt, prompt, sizeof(pwprompt));
+ pwprompt[prompt_len < sizeof(pwprompt) ?
+ prompt_len : sizeof(pwprompt)-1] = '\0';
+ } else {
+ strcpy(pwprompt,
+ "<server failed to send prompt>: ");
+ }
+ echo = ssh2_pkt_getbool();
+ need_pw = TRUE;
+ } else
+ need_pw = FALSE;
+ }
+
if (!method && can_passwd) {
method = AUTH_PASSWORD;
+ ssh_pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
+ ssh_pkt_ctx |= SSH2_PKTCTX_PASSWORD;
sprintf(pwprompt, "%.90s@%.90s's password: ", username,
savedhost);
need_pw = TRUE;
("No more passwords available to try");
ssh2_pkt_addstring("en"); /* language tag */
ssh2_pkt_send();
+ logevent("Unable to authenticate");
connection_fatal("Unable to authenticate");
ssh_state = SSH_STATE_CLOSED;
crReturnV;
}
} else {
- static int pos = 0;
- static char c;
-
- c_write_str(pwprompt);
+ static int ret;
+ c_write_untrusted(pwprompt, strlen(pwprompt));
ssh_send_ok = 1;
- pos = 0;
- while (pos >= 0) {
+ setup_userpass_input(password, sizeof(password), echo);
+ do {
crWaitUntilV(!ispkt);
- while (inlen--)
- switch (c = *in++) {
- case 10:
- case 13:
- password[pos] = 0;
- pos = -1;
- break;
- case 8:
- case 127:
- if (pos > 0)
- pos--;
- break;
- case 21:
- case 27:
- pos = 0;
- break;
- case 3:
- case 4:
- random_save_seed();
- exit(0);
- break;
- default:
- if (pos < sizeof(password)-1)
- password[pos++] = c;
- break;
- }
- }
+ ret = process_userpass_input(in, inlen);
+ } while (ret == 0);
+ if (ret < 0)
+ cleanup_exit(0);
c_write_str("\r\n");
}
}
ssh2_pkt_send();
type = AUTH_TYPE_NONE;
} else {
- unsigned char *blob, *sigdata;
- int blob_len, sigdata_len;
+ unsigned char *pkblob, *sigblob, *sigdata;
+ int pkblob_len, sigblob_len, sigdata_len;
/*
* We have loaded the private key and the server
ssh2_pkt_addstring("publickey"); /* method */
ssh2_pkt_addbool(TRUE);
ssh2_pkt_addstring(key->alg->name);
- blob = key->alg->public_blob(key->data, &blob_len);
+ pkblob = key->alg->public_blob(key->data, &pkblob_len);
ssh2_pkt_addstring_start();
- ssh2_pkt_addstring_data(blob, blob_len);
- sfree(blob);
+ ssh2_pkt_addstring_data(pkblob, pkblob_len);
/*
* The data to be signed is:
memcpy(sigdata + 4, ssh2_session_id, 20);
memcpy(sigdata + 24, pktout.data + 5,
pktout.length - 5);
- blob =
- key->alg->sign(key->data, sigdata, sigdata_len,
- &blob_len);
- ssh2_pkt_addstring_start();
- ssh2_pkt_addstring_data(blob, blob_len);
- sfree(blob);
+ sigblob = key->alg->sign(key->data, sigdata,
+ sigdata_len, &sigblob_len);
+ ssh2_add_sigblob(pkblob, pkblob_len,
+ sigblob, sigblob_len);
+ sfree(pkblob);
+ sfree(sigblob);
sfree(sigdata);
ssh2_pkt_send();
ssh_pkt_defersend();
logevent("Sent password");
type = AUTH_TYPE_PASSWORD;
+ } else if (method == AUTH_KEYBOARD_INTERACTIVE) {
+ if (curr_prompt == 0) {
+ ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE);
+ ssh2_pkt_adduint32(num_prompts);
+ }
+ if (need_pw) { /* only add pw if we just got one! */
+ ssh2_pkt_addstring(password);
+ memset(password, 0, sizeof(password));
+ curr_prompt++;
+ }
+ if (curr_prompt >= num_prompts) {
+ ssh2_pkt_send();
+ } else {
+ /*
+ * If there are prompts remaining, we set
+ * `gotit' so that we won't attempt to get
+ * another packet. Then we go back round the
+ * loop and will end up retrieving another
+ * prompt out of the existing packet. Funky or
+ * what?
+ */
+ gotit = TRUE;
+ }
+ type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
} else {
c_write_str
("No supported authentication methods left to try!\r\n");
ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
ssh2_pkt_addstring("session");
ssh2_pkt_adduint32(mainchan->localid);
- ssh2_pkt_adduint32(0x8000UL); /* our window size */
+ mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
+ ssh2_pkt_adduint32(mainchan->v.v2.locwindow); /* our window size */
ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
ssh2_pkt_send();
crWaitUntilV(ispkt);
mainchan->remoteid = ssh2_pkt_getuint32();
mainchan->type = CHAN_MAINSESSION;
mainchan->closes = 0;
- mainchan->v2.remwindow = ssh2_pkt_getuint32();
- mainchan->v2.remmaxpkt = ssh2_pkt_getuint32();
- mainchan->v2.outbuffer = NULL;
- mainchan->v2.outbuflen = mainchan->v2.outbufsize = 0;
+ mainchan->v.v2.remwindow = ssh2_pkt_getuint32();
+ mainchan->v.v2.remmaxpkt = ssh2_pkt_getuint32();
+ bufchain_init(&mainchan->v.v2.outbuffer);
add234(ssh_channels, mainchan);
logevent("Opened channel for session");
c = find234(ssh_channels, &i, ssh_channelfind);
if (!c)
continue; /* nonexistent channel */
- c->v2.remwindow += ssh2_pkt_getuint32();
+ c->v.v2.remwindow += ssh2_pkt_getuint32();
}
} while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
- bombout(("Server got confused by X11 forwarding request"));
+ bombout(("Unexpected response to X11 forwarding request:"
+ " packet type %d", pktin.type));
crReturnV;
}
logevent("X11 forwarding refused");
}
/*
+ * Enable port forwardings.
+ */
+ {
+ static char *e; /* preserve across crReturn */
+ char type;
+ int n;
+ int sport,dport,sserv,dserv;
+ char sports[256], dports[256], host[256];
+ char buf[1024];
+ struct servent *se;
+
+ ssh_rportfwds = newtree234(ssh_rportcmp_ssh2);
+ /* Add port forwardings. */
+ e = cfg.portfwd;
+ while (*e) {
+ type = *e++;
+ n = 0;
+ while (*e && *e != '\t')
+ sports[n++] = *e++;
+ sports[n] = 0;
+ if (*e == '\t')
+ e++;
+ n = 0;
+ while (*e && *e != ':')
+ host[n++] = *e++;
+ host[n] = 0;
+ if (*e == ':')
+ e++;
+ n = 0;
+ while (*e)
+ dports[n++] = *e++;
+ dports[n] = 0;
+ e++;
+ dport = atoi(dports);
+ dserv = 0;
+ if (dport == 0) {
+ dserv = 1;
+ se = getservbyname(dports, NULL);
+ if (se != NULL) {
+ dport = ntohs(se->s_port);
+ } else {
+ sprintf(buf,
+ "Service lookup failed for destination port \"%s\"",
+ dports);
+ logevent(buf);
+ }
+ }
+ sport = atoi(sports);
+ sserv = 0;
+ if (sport == 0) {
+ sserv = 1;
+ se = getservbyname(sports, NULL);
+ if (se != NULL) {
+ sport = ntohs(se->s_port);
+ } else {
+ sprintf(buf,
+ "Service lookup failed for source port \"%s\"",
+ sports);
+ logevent(buf);
+ }
+ }
+ if (sport && dport) {
+ if (type == 'L') {
+ pfd_addforward(host, dport, sport);
+ sprintf(buf, "Local port %.*s%.*s%d%.*s forwarding to"
+ " %s:%.*s%.*s%d%.*s",
+ sserv ? strlen(sports) : 0, sports,
+ sserv, "(", sport, sserv, ")",
+ host,
+ dserv ? strlen(dports) : 0, dports,
+ dserv, "(", dport, dserv, ")");
+ logevent(buf);
+ } else {
+ struct ssh_rportfwd *pf;
+ pf = smalloc(sizeof(*pf));
+ strcpy(pf->dhost, host);
+ pf->dport = dport;
+ pf->sport = sport;
+ if (add234(ssh_rportfwds, pf) != pf) {
+ sprintf(buf,
+ "Duplicate remote port forwarding to %s:%d",
+ host, dport);
+ logevent(buf);
+ sfree(pf);
+ } else {
+ sprintf(buf, "Requesting remote port %.*s%.*s%d%.*s"
+ " forward to %s:%.*s%.*s%d%.*s",
+ sserv ? strlen(sports) : 0, sports,
+ sserv, "(", sport, sserv, ")",
+ host,
+ dserv ? strlen(dports) : 0, dports,
+ dserv, "(", dport, dserv, ")");
+ logevent(buf);
+ ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
+ ssh2_pkt_addstring("tcpip-forward");
+ ssh2_pkt_addbool(1);/* want reply */
+ if (cfg.rport_acceptall)
+ ssh2_pkt_addstring("0.0.0.0");
+ else
+ ssh2_pkt_addstring("127.0.0.1");
+ ssh2_pkt_adduint32(sport);
+ ssh2_pkt_send();
+
+ do {
+ crWaitUntilV(ispkt);
+ if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
+ unsigned i = ssh2_pkt_getuint32();
+ struct ssh_channel *c;
+ c = find234(ssh_channels, &i, ssh_channelfind);
+ if (!c)
+ continue;/* nonexistent channel */
+ c->v.v2.remwindow += ssh2_pkt_getuint32();
+ }
+ } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
+
+ 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));
+ crReturnV;
+ }
+ logevent("Server refused this port forwarding");
+ } else {
+ logevent("Remote port forwarding enabled");
+ }
+ }
+ }
+ }
+ }
+ }
+
+ /*
* Potentially enable agent forwarding.
*/
if (cfg.agentfwd && agent_exists()) {
c = find234(ssh_channels, &i, ssh_channelfind);
if (!c)
continue; /* nonexistent channel */
- c->v2.remwindow += ssh2_pkt_getuint32();
+ c->v.v2.remwindow += ssh2_pkt_getuint32();
}
} while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
- bombout(
- ("Server got confused by agent forwarding request"));
+ bombout(("Unexpected response to agent forwarding request:"
+ " packet type %d", pktin.type));
crReturnV;
}
logevent("Agent forwarding refused");
ssh2_pkt_addstring("pty-req");
ssh2_pkt_addbool(1); /* want reply */
ssh2_pkt_addstring(cfg.termtype);
- ssh2_pkt_adduint32(cols);
- ssh2_pkt_adduint32(rows);
+ ssh2_pkt_adduint32(term ? term->cols : 80);
+ ssh2_pkt_adduint32(term ? term->rows : 24);
ssh2_pkt_adduint32(0); /* pixel width */
ssh2_pkt_adduint32(0); /* pixel height */
ssh2_pkt_addstring_start();
c = find234(ssh_channels, &i, ssh_channelfind);
if (!c)
continue; /* nonexistent channel */
- c->v2.remwindow += ssh2_pkt_getuint32();
+ c->v.v2.remwindow += ssh2_pkt_getuint32();
}
} while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
- bombout(("Server got confused by pty request"));
+ bombout(("Unexpected response to pty request:"
+ " packet type %d", pktin.type));
crReturnV;
}
c_write_str("Server refused to allocate pty\r\n");
}
/*
- * Start a shell or a remote command.
+ * Start a shell or a remote command. We may have to attempt
+ * this twice if the config data has provided a second choice
+ * of command.
*/
- ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
- ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
- if (cfg.ssh_subsys) {
- ssh2_pkt_addstring("subsystem");
- ssh2_pkt_addbool(1); /* want reply */
- ssh2_pkt_addstring(cfg.remote_cmd_ptr);
- } else if (*cfg.remote_cmd_ptr) {
- ssh2_pkt_addstring("exec");
- ssh2_pkt_addbool(1); /* want reply */
- ssh2_pkt_addstring(cfg.remote_cmd_ptr);
- } else {
- ssh2_pkt_addstring("shell");
- ssh2_pkt_addbool(1); /* want reply */
- }
- ssh2_pkt_send();
- do {
- crWaitUntilV(ispkt);
- if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
- unsigned i = ssh2_pkt_getuint32();
- struct ssh_channel *c;
- c = find234(ssh_channels, &i, ssh_channelfind);
- if (!c)
- continue; /* nonexistent channel */
- c->v2.remwindow += ssh2_pkt_getuint32();
+ while (1) {
+ int subsys;
+ char *cmd;
+
+ if (ssh_fallback_cmd) {
+ subsys = cfg.ssh_subsys2;
+ cmd = cfg.remote_cmd_ptr2;
+ } else {
+ subsys = cfg.ssh_subsys;
+ cmd = cfg.remote_cmd_ptr;
+ }
+
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
+ ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
+ if (subsys) {
+ ssh2_pkt_addstring("subsystem");
+ ssh2_pkt_addbool(1); /* want reply */
+ ssh2_pkt_addstring(cmd);
+ } else if (*cmd) {
+ ssh2_pkt_addstring("exec");
+ ssh2_pkt_addbool(1); /* want reply */
+ ssh2_pkt_addstring(cmd);
+ } else {
+ ssh2_pkt_addstring("shell");
+ ssh2_pkt_addbool(1); /* want reply */
}
- } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
- if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
- if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
- bombout(("Server got confused by shell/command request"));
+ ssh2_pkt_send();
+ do {
+ crWaitUntilV(ispkt);
+ if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
+ unsigned i = ssh2_pkt_getuint32();
+ struct ssh_channel *c;
+ c = find234(ssh_channels, &i, ssh_channelfind);
+ if (!c)
+ continue; /* nonexistent channel */
+ c->v.v2.remwindow += ssh2_pkt_getuint32();
+ }
+ } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
+ if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
+ if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
+ bombout(("Unexpected response to shell/command request:"
+ " packet type %d", pktin.type));
+ crReturnV;
+ }
+ /*
+ * We failed to start the command. If this is the
+ * fallback command, we really are finished; if it's
+ * not, and if the fallback command exists, try falling
+ * back to it before complaining.
+ */
+ if (!ssh_fallback_cmd && cfg.remote_cmd_ptr2 != NULL) {
+ logevent("Primary command failed; attempting fallback");
+ ssh_fallback_cmd = TRUE;
+ continue;
+ }
+ bombout(("Server refused to start a shell/command"));
crReturnV;
+ } else {
+ logevent("Started a shell/command");
}
- bombout(("Server refused to start a shell/command"));
- crReturnV;
- } else {
- logevent("Started a shell/command");
+ break;
}
ssh_state = SSH_STATE_SESSION;
/*
* Transfer data!
*/
- ldisc_send(NULL, 0); /* cause ldisc to notice changes */
+ ldisc_send(NULL, 0, 0); /* cause ldisc to notice changes */
ssh_send_ok = 1;
while (1) {
static int try_send;
continue; /* extended but not stderr */
ssh2_pkt_getstring(&data, &length);
if (data) {
+ int bufsize;
+ c->v.v2.locwindow -= length;
switch (c->type) {
case CHAN_MAINSESSION:
- from_backend(pktin.type ==
- SSH2_MSG_CHANNEL_EXTENDED_DATA, data,
- length);
+ bufsize =
+ from_backend(frontend, pktin.type ==
+ SSH2_MSG_CHANNEL_EXTENDED_DATA,
+ data, length);
break;
case CHAN_X11:
- x11_send(c->u.x11.s, data, length);
+ 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) {
c->u.a.lensofar = 0;
}
}
+ bufsize = 0;
break;
}
/*
- * Enlarge the window again at the remote
- * side, just in case it ever runs down and
- * they fail to send us any more data.
+ * If we are not buffering too much data,
+ * enlarge the window again at the remote side.
*/
- ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
- ssh2_pkt_adduint32(c->remoteid);
- ssh2_pkt_adduint32(length);
- ssh2_pkt_send();
+ if (bufsize < OUR_V2_WINSIZE)
+ ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
}
} else if (pktin.type == SSH2_MSG_DISCONNECT) {
ssh_state = SSH_STATE_CLOSED;
logevent("Received disconnect message");
crReturnV;
- } else if (pktin.type == SSH2_MSG_CHANNEL_REQUEST) {
- continue; /* exit status et al; ignore (FIXME?) */
} else if (pktin.type == SSH2_MSG_CHANNEL_EOF) {
unsigned i = ssh2_pkt_getuint32();
struct ssh_channel *c;
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 = ssh2_pkt_getuint32();
struct ssh_channel *c;
c = find234(ssh_channels, &i, ssh_channelfind);
- if (!c)
- continue; /* nonexistent channel */
- if (c->closes == 0) {
- ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
- ssh2_pkt_adduint32(c->remoteid);
- ssh2_pkt_send();
+ if (!c || ((int)c->remoteid) == -1) {
+ bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
+ c ? "half-open" : "nonexistent", i));
}
/* Do pre-close processing on the channel. */
switch (c->type) {
case CHAN_MAINSESSION:
break; /* nothing to see here, move along */
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) {
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
+ ssh2_pkt_adduint32(c->remoteid);
+ ssh2_pkt_send();
+ }
del234(ssh_channels, c);
- sfree(c->v2.outbuffer);
+ bufchain_clear(&c->v.v2.outbuffer);
sfree(c);
/*
* See if that was the last channel left open.
*/
if (count234(ssh_channels) == 0) {
+#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.
+ */
logevent("All channels closed. Disconnecting");
ssh2_pkt_init(SSH2_MSG_DISCONNECT);
ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION);
ssh2_pkt_addstring("All open channels closed");
ssh2_pkt_addstring("en"); /* language tag */
ssh2_pkt_send();
+#endif
ssh_state = SSH_STATE_CLOSED;
crReturnV;
}
c = find234(ssh_channels, &i, ssh_channelfind);
if (!c)
continue; /* nonexistent channel */
- c->v2.remwindow += ssh2_pkt_getuint32();
+ c->v.v2.remwindow += ssh2_pkt_getuint32();
try_send = TRUE;
+ } else if (pktin.type == SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
+ unsigned i = ssh2_pkt_getuint32();
+ 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 = ssh2_pkt_getuint32();
+ c->type = CHAN_SOCKDATA;
+ c->v.v2.remwindow = ssh2_pkt_getuint32();
+ c->v.v2.remmaxpkt = ssh2_pkt_getuint32();
+ 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.
+ */
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
+ ssh2_pkt_adduint32(c->remoteid);
+ ssh2_pkt_send();
+ }
+ } else if (pktin.type == SSH2_MSG_CHANNEL_OPEN_FAILURE) {
+ unsigned i = ssh2_pkt_getuint32();
+ 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 */
+
+ logevent("Forwarded connection refused by server");
+
+ 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;
+ struct ssh_channel *c;
+
+ localid = ssh2_pkt_getuint32();
+ ssh2_pkt_getstring(&type, &typelen);
+ want_reply = ssh2_pkt_getbool();
+
+ /*
+ * 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);
+ ssh2_pkt_init(SSH2_MSG_DISCONNECT);
+ ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION);
+ ssh2_pkt_addstring(buf);
+ ssh2_pkt_addstring("en"); /* language tag */
+ ssh2_pkt_send();
+ connection_fatal("%s", buf);
+ ssh_state = SSH_STATE_CLOSED;
+ crReturnV;
+ }
+
+ /*
+ * Having got the channel number, we now look at
+ * the request type string to see if it's something
+ * we recognise.
+ */
+ if (typelen == 11 && !memcmp(type, "exit-status", 11) &&
+ c == mainchan) {
+ /* We recognise "exit-status" on the primary channel. */
+ char buf[100];
+ ssh_exitcode = ssh2_pkt_getuint32();
+ sprintf(buf, "Server sent command exit status %d",
+ ssh_exitcode);
+ logevent(buf);
+ if (want_reply) {
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_SUCCESS);
+ ssh2_pkt_adduint32(c->remoteid);
+ ssh2_pkt_send();
+ }
+ } 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.
+ */
+ if (want_reply) {
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_FAILURE);
+ ssh2_pkt_adduint32(c->remoteid);
+ ssh2_pkt_send();
+ }
+ }
+ } else if (pktin.type == SSH2_MSG_GLOBAL_REQUEST) {
+ char *type;
+ int typelen, want_reply;
+
+ ssh2_pkt_getstring(&type, &typelen);
+ want_reply = ssh2_pkt_getbool();
+
+ /*
+ * 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) {
+ ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE);
+ ssh2_pkt_send();
+ }
} else if (pktin.type == SSH2_MSG_CHANNEL_OPEN) {
char *type;
int typelen;
char *error = NULL;
struct ssh_channel *c;
+ unsigned remid, winsize, pktsize;
ssh2_pkt_getstring(&type, &typelen);
c = smalloc(sizeof(struct ssh_channel));
+ remid = ssh2_pkt_getuint32();
+ winsize = ssh2_pkt_getuint32();
+ pktsize = ssh2_pkt_getuint32();
+
if (typelen == 3 && !memcmp(type, "x11", 3)) {
if (!ssh_X11_fwd_enabled)
error = "X11 forwarding is not enabled";
} else {
c->type = CHAN_X11;
}
+ } else if (typelen == 15 &&
+ !memcmp(type, "forwarded-tcpip", 15)) {
+ struct ssh_rportfwd pf, *realpf;
+ char *dummy;
+ int dummylen;
+ ssh2_pkt_getstring(&dummy, &dummylen);/* skip address */
+ pf.sport = ssh2_pkt_getuint32();
+ realpf = find234(ssh_rportfwds, &pf, NULL);
+ if (realpf == NULL) {
+ error = "Remote port is not recognised";
+ } else {
+ char *e = pfd_newconnect(&c->u.pfd.s, realpf->dhost,
+ realpf->dport, c);
+ char buf[1024];
+ sprintf(buf, "Received remote port open request for %s:%d",
+ realpf->dhost, realpf->dport);
+ logevent(buf);
+ if (e != NULL) {
+ sprintf(buf, "Port open failed: %s", e);
+ logevent(buf);
+ 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 = "Unsupported channel type requested";
}
- c->remoteid = ssh2_pkt_getuint32();
+ c->remoteid = remid;
if (error) {
ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE);
ssh2_pkt_adduint32(c->remoteid);
} else {
c->localid = alloc_channel_id();
c->closes = 0;
- c->v2.remwindow = ssh2_pkt_getuint32();
- c->v2.remmaxpkt = ssh2_pkt_getuint32();
- c->v2.outbuffer = NULL;
- c->v2.outbuflen = c->v2.outbufsize = 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);
ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
ssh2_pkt_adduint32(c->remoteid);
ssh2_pkt_adduint32(c->localid);
- ssh2_pkt_adduint32(0x8000UL); /* our window size */
+ ssh2_pkt_adduint32(c->v.v2.locwindow);
ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
ssh2_pkt_send();
}
/*
* Try to send data on all channels if we can.
*/
- for (i = 0; NULL != (c = index234(ssh_channels, i)); i++)
- ssh2_try_send(c);
+ for (i = 0; NULL != (c = index234(ssh_channels, i)); i++) {
+ int 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;
+ }
+ }
+ }
}
}
*
* Returns an error message, or NULL on success.
*/
-static char *ssh_init(char *host, int port, char **realhost)
+static char *ssh_init(void *frontend_handle,
+ char *host, int port, char **realhost, int nodelay)
{
char *p;
return "Microsoft high encryption pack not installed!";
#endif
+ frontend = frontend_handle;
+
ssh_send_ok = 0;
ssh_editing = 0;
ssh_echoing = 0;
+ ssh1_throttle_count = 0;
+ ssh_overall_bufsize = 0;
+ ssh_fallback_cmd = 0;
- p = connect_to_host(host, port, realhost);
+ p = connect_to_host(host, port, realhost, nodelay);
if (p != NULL)
return p;
/*
* Called to send data down the Telnet connection.
*/
-static void ssh_send(char *buf, int len)
+static int ssh_send(char *buf, int len)
{
if (s == NULL || ssh_protocol == NULL)
- return;
+ return 0;
ssh_protocol(buf, len, 0);
+
+ return ssh_sendbuffer();
+}
+
+/*
+ * Called to query the current amount of buffered stdin data.
+ */
+static int ssh_sendbuffer(void)
+{
+ int override_value;
+
+ if (s == NULL || ssh_protocol == NULL)
+ return 0;
+
+ /*
+ * If the SSH socket itself has backed up, add the total backup
+ * size on that to any individual buffer on the stdin channel.
+ */
+ override_value = 0;
+ if (ssh_throttled_all)
+ override_value = ssh_overall_bufsize;
+
+ if (ssh_version == 1) {
+ return override_value;
+ } else if (ssh_version == 2) {
+ if (!mainchan || mainchan->closes > 0)
+ return override_value;
+ else
+ return override_value + bufchain_size(&mainchan->v.v2.outbuffer);
+ }
+
+ return 0;
}
/*
break;
case SSH_STATE_SESSION:
if (!cfg.nopty) {
+ if (!term)
+ return;
if (ssh_version == 1) {
send_packet(SSH1_CMSG_WINDOW_SIZE,
- PKT_INT, rows, PKT_INT, cols,
+ PKT_INT, term->rows, PKT_INT, term->cols,
PKT_INT, 0, PKT_INT, 0, PKT_END);
} else {
ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
ssh2_pkt_adduint32(mainchan->remoteid);
ssh2_pkt_addstring("window-change");
ssh2_pkt_addbool(0);
- ssh2_pkt_adduint32(cols);
- ssh2_pkt_adduint32(rows);
+ ssh2_pkt_adduint32(term->cols);
+ ssh2_pkt_adduint32(term->rows);
ssh2_pkt_adduint32(0);
ssh2_pkt_adduint32(0);
ssh2_pkt_send();
if (ssh_state == SSH_STATE_CLOSED
|| ssh_state == SSH_STATE_PREPACKET) return;
if (ssh_version == 1) {
- send_packet(SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
+ if (!(ssh_remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
+ send_packet(SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
} else {
ssh2_pkt_init(SSH2_MSG_IGNORE);
ssh2_pkt_addstring_start();
}
}
+void *new_sock_channel(Socket s)
+{
+ struct ssh_channel *c;
+ c = smalloc(sizeof(struct ssh_channel));
+
+ if (c) {
+ c->remoteid = -1; /* to be set when open confirmed */
+ c->localid = alloc_channel_id();
+ c->closes = 0;
+ c->type = CHAN_SOCKDATA_DORMANT;/* identify channel type */
+ c->u.pfd.s = s;
+ bufchain_init(&c->v.v2.outbuffer);
+ add234(ssh_channels, c);
+ }
+ return c;
+}
+
+/*
+ * This is called when stdout/stderr (the entity to which
+ * from_backend sends data) manages to clear some backlog.
+ */
+void ssh_unthrottle(int bufsize)
+{
+ if (ssh_version == 1) {
+ if (ssh1_stdout_throttling && bufsize < SSH1_BUFFER_LIMIT) {
+ ssh1_stdout_throttling = 0;
+ ssh1_throttle(-1);
+ }
+ } else {
+ if (mainchan && mainchan->closes == 0)
+ ssh2_set_window(mainchan, OUR_V2_WINSIZE - bufsize);
+ }
+}
+
+void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
+{
+ struct ssh_channel *c = (struct ssh_channel *)channel;
+ char buf[1024];
+
+ sprintf(buf, "Opening forwarded connection to %.512s:%d", hostname, port);
+ logevent(buf);
+
+ if (ssh_version == 1) {
+ send_packet(SSH1_MSG_PORT_OPEN,
+ PKT_INT, c->localid,
+ PKT_STR, hostname,
+ PKT_INT, port,
+ //PKT_STR, <org:orgport>,
+ PKT_END);
+ } else {
+ ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
+ ssh2_pkt_addstring("direct-tcpip");
+ ssh2_pkt_adduint32(c->localid);
+ c->v.v2.locwindow = OUR_V2_WINSIZE;
+ ssh2_pkt_adduint32(c->v.v2.locwindow);/* our window size */
+ ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
+ ssh2_pkt_addstring(hostname);
+ ssh2_pkt_adduint32(port);
+ /*
+ * We make up values for the originator data; partly it's
+ * too much hassle to keep track, and partly I'm not
+ * convinced the server should be told details like that
+ * about my local network configuration.
+ */
+ ssh2_pkt_addstring("client-side-connection");
+ ssh2_pkt_adduint32(0);
+ ssh2_pkt_send();
+ }
+}
+
+
static Socket ssh_socket(void)
{
return s;
return FALSE;
}
+static int ssh_return_exitcode(void)
+{
+ return ssh_exitcode;
+}
+
Backend ssh_backend = {
ssh_init,
ssh_send,
+ ssh_sendbuffer,
ssh_size,
ssh_special,
ssh_socket,
+ ssh_return_exitcode,
ssh_sendok,
ssh_ldisc,
+ ssh_unthrottle,
22
};
projects / u / mdw / putty / blobdiff