}
}
+static void ssh1_smsg_stdout_stderr_data(Ssh ssh, struct Packet *pktin)
+{
+ char *string;
+ int stringlen, bufsize;
+
+ ssh_pkt_getstring(pktin, &string, &stringlen);
+ if (string == NULL) {
+ bombout(("Incoming terminal data packet was badly formed"));
+ return;
+ }
+
+ bufsize = from_backend(ssh->frontend, pktin->type == SSH1_SMSG_STDERR_DATA,
+ string, stringlen);
+ if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
+ ssh->v1_stdout_throttling = 1;
+ ssh1_throttle(ssh, +1);
+ }
+}
+
+static void ssh1_smsg_x11_open(Ssh ssh, struct Packet *pktin)
+{
+ /* Remote side is trying to open a channel to talk to our
+ * X-Server. Give them back a local channel number. */
+ struct ssh_channel *c;
+ int remoteid = ssh_pkt_getuint32(pktin);
+
+ logevent("Received X11 connect request");
+ /* Refuse if X11 forwarding is disabled. */
+ if (!ssh->X11_fwd_enabled) {
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
+ PKT_INT, remoteid, PKT_END);
+ logevent("Rejected X11 connect request");
+ } else {
+ c = snew(struct ssh_channel);
+ c->ssh = ssh;
+
+ if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
+ ssh->x11auth, NULL, -1, &ssh->cfg) != NULL) {
+ logevent("Opening X11 forward connection failed");
+ sfree(c);
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
+ PKT_INT, remoteid, PKT_END);
+ } else {
+ logevent
+ ("Opening X11 forward connection succeeded");
+ c->remoteid = remoteid;
+ c->localid = alloc_channel_id(ssh);
+ c->closes = 0;
+ c->v.v1.throttling = 0;
+ c->type = CHAN_X11; /* identify channel type */
+ add234(ssh->channels, c);
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
+ PKT_INT, c->remoteid, PKT_INT,
+ c->localid, PKT_END);
+ logevent("Opened X11 forward channel");
+ }
+ }
+}
+
+static void ssh1_smsg_agent_open(Ssh ssh, struct Packet *pktin)
+{
+ /* Remote side is trying to open a channel to talk to our
+ * agent. Give them back a local channel number. */
+ struct ssh_channel *c;
+ int remoteid = ssh_pkt_getuint32(pktin);
+
+ /* Refuse if agent forwarding is disabled. */
+ if (!ssh->agentfwd_enabled) {
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
+ PKT_INT, remoteid, PKT_END);
+ } else {
+ c = snew(struct ssh_channel);
+ c->ssh = ssh;
+ c->remoteid = remoteid;
+ c->localid = alloc_channel_id(ssh);
+ c->closes = 0;
+ c->v.v1.throttling = 0;
+ c->type = CHAN_AGENT; /* identify channel type */
+ c->u.a.lensofar = 0;
+ add234(ssh->channels, c);
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
+ PKT_INT, c->remoteid, PKT_INT, c->localid,
+ PKT_END);
+ }
+}
+
+static void ssh1_msg_port_open(Ssh ssh, struct Packet *pktin)
+{
+ /* Remote side is trying to open a channel to talk to a
+ * forwarded port. Give them back a local channel number. */
+ struct ssh_channel *c;
+ struct ssh_rportfwd pf;
+ int remoteid;
+ int hostsize, port;
+ char *host, buf[1024];
+ const char *e;
+ c = snew(struct ssh_channel);
+ c->ssh = ssh;
+
+ remoteid = ssh_pkt_getuint32(pktin);
+ ssh_pkt_getstring(pktin, &host, &hostsize);
+ port = ssh_pkt_getuint32(pktin);
+
+ if (hostsize >= lenof(pf.dhost))
+ hostsize = lenof(pf.dhost)-1;
+ memcpy(pf.dhost, host, hostsize);
+ pf.dhost[hostsize] = '\0';
+ pf.dport = port;
+
+ if (find234(ssh->rportfwds, &pf, NULL) == NULL) {
+ sprintf(buf, "Rejected remote port open request for %s:%d",
+ pf.dhost, port);
+ logevent(buf);
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
+ PKT_INT, remoteid, PKT_END);
+ } else {
+ sprintf(buf, "Received remote port open request for %s:%d",
+ pf.dhost, port);
+ logevent(buf);
+ e = pfd_newconnect(&c->u.pfd.s, pf.dhost, port,
+ c, &ssh->cfg);
+ if (e != NULL) {
+ char buf[256];
+ sprintf(buf, "Port open failed: %s", e);
+ logevent(buf);
+ sfree(c);
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
+ PKT_INT, remoteid, PKT_END);
+ } else {
+ c->remoteid = remoteid;
+ c->localid = alloc_channel_id(ssh);
+ c->closes = 0;
+ c->v.v1.throttling = 0;
+ c->type = CHAN_SOCKDATA; /* identify channel type */
+ add234(ssh->channels, c);
+ send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
+ PKT_INT, c->remoteid, PKT_INT,
+ c->localid, PKT_END);
+ logevent("Forwarded port opened successfully");
+ }
+ }
+}
+
+static void ssh1_msg_channel_open_confirmation(Ssh ssh, struct Packet *pktin)
+{
+ unsigned int remoteid = ssh_pkt_getuint32(pktin);
+ unsigned int localid = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+
+ c = find234(ssh->channels, &remoteid, ssh_channelfind);
+ if (c && c->type == CHAN_SOCKDATA_DORMANT) {
+ c->remoteid = localid;
+ c->type = CHAN_SOCKDATA;
+ c->v.v1.throttling = 0;
+ pfd_confirm(c->u.pfd.s);
+ }
+
+ if (c && c->closes) {
+ /*
+ * We have a pending close on this channel,
+ * which we decided on before the server acked
+ * the channel open. So now we know the
+ * remoteid, we can close it again.
+ */
+ send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE,
+ PKT_INT, c->remoteid, PKT_END);
+ }
+}
+
+static void ssh1_msg_channel_open_failure(Ssh ssh, struct Packet *pktin)
+{
+ unsigned int remoteid = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+
+ c = find234(ssh->channels, &remoteid, ssh_channelfind);
+ if (c && c->type == CHAN_SOCKDATA_DORMANT) {
+ logevent("Forwarded connection refused by server");
+ pfd_close(c->u.pfd.s);
+ del234(ssh->channels, c);
+ sfree(c);
+ }
+}
+
+static void ssh1_msg_channel_close(Ssh ssh, struct Packet *pktin)
+{
+ /* Remote side closes a channel. */
+ unsigned i = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (c && ((int)c->remoteid) != -1) {
+ int closetype;
+ closetype =
+ (pktin->type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
+
+ if ((c->closes == 0) && (c->type == CHAN_X11)) {
+ logevent("Forwarded X11 connection terminated");
+ assert(c->u.x11.s != NULL);
+ x11_close(c->u.x11.s);
+ c->u.x11.s = NULL;
+ }
+ if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
+ logevent("Forwarded port closed");
+ assert(c->u.pfd.s != NULL);
+ pfd_close(c->u.pfd.s);
+ c->u.pfd.s = NULL;
+ }
+
+ c->closes |= (closetype << 2); /* seen this message */
+ if (!(c->closes & closetype)) {
+ send_packet(ssh, pktin->type, PKT_INT, c->remoteid,
+ PKT_END);
+ c->closes |= closetype; /* sent it too */
+ }
+
+ if (c->closes == 15) {
+ del234(ssh->channels, c);
+ sfree(c);
+ }
+ } else {
+ bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
+ pktin->type == SSH1_MSG_CHANNEL_CLOSE ? "" :
+ "_CONFIRMATION", c ? "half-open" : "nonexistent",
+ i));
+ }
+}
+
+static void ssh1_msg_channel_data(Ssh ssh, struct Packet *pktin)
+{
+ /* Data sent down one of our channels. */
+ int i = ssh_pkt_getuint32(pktin);
+ char *p;
+ int len;
+ struct ssh_channel *c;
+
+ ssh_pkt_getstring(pktin, &p, &len);
+
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (c) {
+ int bufsize = 0;
+ switch (c->type) {
+ case CHAN_X11:
+ bufsize = x11_send(c->u.x11.s, p, len);
+ break;
+ case CHAN_SOCKDATA:
+ bufsize = pfd_send(c->u.pfd.s, p, len);
+ break;
+ case CHAN_AGENT:
+ /* Data for an agent message. Buffer it. */
+ while (len > 0) {
+ if (c->u.a.lensofar < 4) {
+ int l = min(4 - c->u.a.lensofar, len);
+ memcpy(c->u.a.msglen + c->u.a.lensofar, p,
+ l);
+ p += l;
+ len -= l;
+ c->u.a.lensofar += l;
+ }
+ if (c->u.a.lensofar == 4) {
+ c->u.a.totallen =
+ 4 + GET_32BIT(c->u.a.msglen);
+ c->u.a.message = snewn(c->u.a.totallen,
+ unsigned char);
+ memcpy(c->u.a.message, c->u.a.msglen, 4);
+ }
+ if (c->u.a.lensofar >= 4 && len > 0) {
+ int l =
+ min(c->u.a.totallen - c->u.a.lensofar,
+ len);
+ memcpy(c->u.a.message + c->u.a.lensofar, p,
+ l);
+ p += l;
+ len -= l;
+ c->u.a.lensofar += l;
+ }
+ if (c->u.a.lensofar == c->u.a.totallen) {
+ void *reply;
+ int replylen;
+ if (agent_query(c->u.a.message,
+ c->u.a.totallen,
+ &reply, &replylen,
+ ssh_agentf_callback, c))
+ ssh_agentf_callback(c, reply, replylen);
+ sfree(c->u.a.message);
+ c->u.a.lensofar = 0;
+ }
+ }
+ bufsize = 0; /* agent channels never back up */
+ break;
+ }
+ if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
+ c->v.v1.throttling = 1;
+ ssh1_throttle(ssh, +1);
+ }
+ }
+}
+
+static void ssh1_smsg_exit_status(Ssh ssh, struct Packet *pktin)
+{
+ char buf[100];
+ ssh->exitcode = ssh_pkt_getuint32(pktin);
+ sprintf(buf, "Server sent command exit status %d",
+ ssh->exitcode);
+ logevent(buf);
+ send_packet(ssh, SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
+ /*
+ * In case `helpful' firewalls or proxies tack
+ * extra human-readable text on the end of the
+ * session which we might mistake for another
+ * encrypted packet, we close the session once
+ * we've sent EXIT_CONFIRMATION.
+ */
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+}
+
static void do_ssh1_connection(Ssh ssh, unsigned char *in, int inlen,
struct Packet *pktin)
{
crBegin(ssh->do_ssh1_connection_crstate);
+ ssh->packet_dispatch[SSH1_SMSG_STDOUT_DATA] =
+ ssh->packet_dispatch[SSH1_SMSG_STDERR_DATA] =
+ ssh1_smsg_stdout_stderr_data;
+
+ ssh->packet_dispatch[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION] =
+ ssh1_msg_channel_open_confirmation;
+ ssh->packet_dispatch[SSH1_MSG_CHANNEL_OPEN_FAILURE] =
+ ssh1_msg_channel_open_failure;
+ ssh->packet_dispatch[SSH1_MSG_CHANNEL_CLOSE] =
+ ssh->packet_dispatch[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION] =
+ ssh1_msg_channel_close;
+ ssh->packet_dispatch[SSH1_MSG_CHANNEL_DATA] = ssh1_msg_channel_data;
+ ssh->packet_dispatch[SSH1_SMSG_EXIT_STATUS] = ssh1_smsg_exit_status;
+
if (ssh->cfg.agentfwd && agent_exists()) {
logevent("Requesting agent forwarding");
send_packet(ssh, SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
} else {
logevent("Agent forwarding enabled");
ssh->agentfwd_enabled = TRUE;
+ ssh->packet_dispatch[SSH1_SMSG_AGENT_OPEN] = ssh1_smsg_agent_open;
}
}
} else {
logevent("X11 forwarding enabled");
ssh->X11_fwd_enabled = TRUE;
+ ssh->packet_dispatch[SSH1_SMSG_X11_OPEN] = ssh1_smsg_x11_open;
}
}
} else if (pktin->type == SSH1_SMSG_FAILURE) {
c_write_str(ssh, "Server refused port"
" forwarding\r\n");
+ logevent("Server refused this port forwarding");
+ } else {
+ logevent("Remote port forwarding enabled");
+ ssh->packet_dispatch[SSH1_MSG_PORT_OPEN] =
+ ssh1_msg_port_open;
}
- logevent("Remote port forwarding enabled");
}
}
sfree(sportdesc);
ssh->send_ok = 1;
ssh->channels = newtree234(ssh_channelcmp);
while (1) {
- crReturnV;
- if (pktin) {
- if (pktin->type == SSH1_SMSG_STDOUT_DATA ||
- pktin->type == SSH1_SMSG_STDERR_DATA) {
- char *string;
- int stringlen, bufsize;
-
- ssh_pkt_getstring(pktin, &string, &stringlen);
- if (string == NULL) {
- bombout(("Incoming terminal data packet was badly formed"));
- crStopV;
- }
-
- bufsize =
- from_backend(ssh->frontend,
- pktin->type == SSH1_SMSG_STDERR_DATA,
- string, stringlen);
- if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
- ssh->v1_stdout_throttling = 1;
- ssh1_throttle(ssh, +1);
- }
- } else if (pktin->type == SSH1_MSG_DISCONNECT) {
- ssh_closing((Plug)ssh, NULL, 0, 0);
- logevent("Received disconnect request");
- crStopV;
- } else if (pktin->type == SSH1_SMSG_X11_OPEN) {
- /* Remote side is trying to open a channel to talk to our
- * X-Server. Give them back a local channel number. */
- struct ssh_channel *c;
- int remoteid = ssh_pkt_getuint32(pktin);
-
- logevent("Received X11 connect request");
- /* Refuse if X11 forwarding is disabled. */
- if (!ssh->X11_fwd_enabled) {
- send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
- PKT_INT, remoteid, PKT_END);
- logevent("Rejected X11 connect request");
- } else {
- c = snew(struct ssh_channel);
- c->ssh = ssh;
-
- if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
- ssh->x11auth, NULL, -1, &ssh->cfg) != NULL) {
- logevent("Opening X11 forward connection failed");
- sfree(c);
- send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
- PKT_INT, remoteid, PKT_END);
- } else {
- logevent
- ("Opening X11 forward connection succeeded");
- c->remoteid = remoteid;
- c->localid = alloc_channel_id(ssh);
- c->closes = 0;
- c->v.v1.throttling = 0;
- c->type = CHAN_X11; /* identify channel type */
- add234(ssh->channels, c);
- send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
- PKT_INT, c->remoteid, PKT_INT,
- c->localid, PKT_END);
- logevent("Opened X11 forward channel");
- }
- }
- } else if (pktin->type == SSH1_SMSG_AGENT_OPEN) {
- /* Remote side is trying to open a channel to talk to our
- * agent. Give them back a local channel number. */
- struct ssh_channel *c;
- int remoteid = ssh_pkt_getuint32(pktin);
-
- /* Refuse if agent forwarding is disabled. */
- if (!ssh->agentfwd_enabled) {
- send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
- PKT_INT, remoteid, PKT_END);
- } else {
- c = snew(struct ssh_channel);
- c->ssh = ssh;
- c->remoteid = remoteid;
- c->localid = alloc_channel_id(ssh);
- c->closes = 0;
- c->v.v1.throttling = 0;
- c->type = CHAN_AGENT; /* identify channel type */
- c->u.a.lensofar = 0;
- add234(ssh->channels, c);
- send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
- PKT_INT, c->remoteid, PKT_INT, c->localid,
- PKT_END);
- }
- } else if (pktin->type == SSH1_MSG_PORT_OPEN) {
- /* Remote side is trying to open a channel to talk to a
- * forwarded port. Give them back a local channel number. */
- struct ssh_channel *c;
- struct ssh_rportfwd pf;
- int remoteid;
- int hostsize, port;
- char *host, buf[1024];
- const char *e;
- c = snew(struct ssh_channel);
- c->ssh = ssh;
-
- remoteid = ssh_pkt_getuint32(pktin);
- ssh_pkt_getstring(pktin, &host, &hostsize);
- port = ssh_pkt_getuint32(pktin);
-
- if (hostsize >= lenof(pf.dhost))
- hostsize = lenof(pf.dhost)-1;
- memcpy(pf.dhost, host, hostsize);
- pf.dhost[hostsize] = '\0';
- pf.dport = port;
-
- if (find234(ssh->rportfwds, &pf, NULL) == NULL) {
- sprintf(buf, "Rejected remote port open request for %s:%d",
- pf.dhost, port);
- logevent(buf);
- send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
- PKT_INT, remoteid, PKT_END);
- } else {
- sprintf(buf, "Received remote port open request for %s:%d",
- pf.dhost, port);
- logevent(buf);
- e = pfd_newconnect(&c->u.pfd.s, pf.dhost, port,
- c, &ssh->cfg);
- if (e != NULL) {
- char buf[256];
- sprintf(buf, "Port open failed: %s", e);
- logevent(buf);
- sfree(c);
- send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
- PKT_INT, remoteid, PKT_END);
- } else {
- c->remoteid = remoteid;
- c->localid = alloc_channel_id(ssh);
- c->closes = 0;
- c->v.v1.throttling = 0;
- c->type = CHAN_SOCKDATA; /* identify channel type */
- add234(ssh->channels, c);
- send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
- PKT_INT, c->remoteid, PKT_INT,
- c->localid, PKT_END);
- logevent("Forwarded port opened successfully");
- }
- }
-
- } else if (pktin->type == SSH1_MSG_CHANNEL_OPEN_CONFIRMATION) {
- unsigned int remoteid = ssh_pkt_getuint32(pktin);
- unsigned int localid = ssh_pkt_getuint32(pktin);
- struct ssh_channel *c;
-
- c = find234(ssh->channels, &remoteid, ssh_channelfind);
- if (c && c->type == CHAN_SOCKDATA_DORMANT) {
- c->remoteid = localid;
- c->type = CHAN_SOCKDATA;
- c->v.v1.throttling = 0;
- pfd_confirm(c->u.pfd.s);
- }
-
- if (c && c->closes) {
- /*
- * We have a pending close on this channel,
- * which we decided on before the server acked
- * the channel open. So now we know the
- * remoteid, we can close it again.
- */
- send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE,
- PKT_INT, c->remoteid, PKT_END);
- }
-
- } else if (pktin->type == SSH1_MSG_CHANNEL_OPEN_FAILURE) {
- unsigned int remoteid = ssh_pkt_getuint32(pktin);
- struct ssh_channel *c;
- c = find234(ssh->channels, &remoteid, ssh_channelfind);
- if (c && c->type == CHAN_SOCKDATA_DORMANT) {
- logevent("Forwarded connection refused by server");
- pfd_close(c->u.pfd.s);
- del234(ssh->channels, c);
- sfree(c);
- }
-
- } else if (pktin->type == SSH1_MSG_CHANNEL_CLOSE ||
- pktin->type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
- /* Remote side closes a channel. */
- unsigned i = ssh_pkt_getuint32(pktin);
- struct ssh_channel *c;
- c = find234(ssh->channels, &i, ssh_channelfind);
- if (c && ((int)c->remoteid) != -1) {
- int closetype;
- closetype =
- (pktin->type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
-
- if ((c->closes == 0) && (c->type == CHAN_X11)) {
- logevent("Forwarded X11 connection terminated");
- assert(c->u.x11.s != NULL);
- x11_close(c->u.x11.s);
- c->u.x11.s = NULL;
- }
- if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
- logevent("Forwarded port closed");
- assert(c->u.pfd.s != NULL);
- pfd_close(c->u.pfd.s);
- c->u.pfd.s = NULL;
- }
-
- c->closes |= (closetype << 2); /* seen this message */
- if (!(c->closes & closetype)) {
- send_packet(ssh, pktin->type, PKT_INT, c->remoteid,
- PKT_END);
- c->closes |= closetype; /* sent it too */
- }
+ /*
+ * By this point, most incoming packets are already being
+ * handled by the dispatch table, and we need only pay
+ * attention to the unusual ones.
+ */
- if (c->closes == 15) {
- del234(ssh->channels, c);
- sfree(c);
- }
- } else {
- bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
- pktin->type == SSH1_MSG_CHANNEL_CLOSE ? "" :
- "_CONFIRMATION", c ? "half-open" : "nonexistent",
- i));
- crStopV;
- }
- } else if (pktin->type == SSH1_MSG_CHANNEL_DATA) {
- /* Data sent down one of our channels. */
- int i = ssh_pkt_getuint32(pktin);
- char *p;
- int len;
- struct ssh_channel *c;
-
- ssh_pkt_getstring(pktin, &p, &len);
-
- c = find234(ssh->channels, &i, ssh_channelfind);
- if (c) {
- int bufsize = 0;
- switch (c->type) {
- case CHAN_X11:
- bufsize = x11_send(c->u.x11.s, p, len);
- break;
- case CHAN_SOCKDATA:
- bufsize = pfd_send(c->u.pfd.s, p, len);
- break;
- case CHAN_AGENT:
- /* Data for an agent message. Buffer it. */
- while (len > 0) {
- if (c->u.a.lensofar < 4) {
- int l = min(4 - c->u.a.lensofar, len);
- memcpy(c->u.a.msglen + c->u.a.lensofar, p,
- l);
- p += l;
- len -= l;
- c->u.a.lensofar += l;
- }
- if (c->u.a.lensofar == 4) {
- c->u.a.totallen =
- 4 + GET_32BIT(c->u.a.msglen);
- c->u.a.message = snewn(c->u.a.totallen,
- unsigned char);
- memcpy(c->u.a.message, c->u.a.msglen, 4);
- }
- if (c->u.a.lensofar >= 4 && len > 0) {
- int l =
- min(c->u.a.totallen - c->u.a.lensofar,
- len);
- memcpy(c->u.a.message + c->u.a.lensofar, p,
- l);
- p += l;
- len -= l;
- c->u.a.lensofar += l;
- }
- if (c->u.a.lensofar == c->u.a.totallen) {
- void *reply;
- int replylen;
- if (agent_query(c->u.a.message,
- c->u.a.totallen,
- &reply, &replylen,
- ssh_agentf_callback, c))
- ssh_agentf_callback(c, reply, replylen);
- sfree(c->u.a.message);
- c->u.a.lensofar = 0;
- }
- }
- bufsize = 0; /* agent channels never back up */
- break;
- }
- if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
- c->v.v1.throttling = 1;
- ssh1_throttle(ssh, +1);
- }
- }
- } else if (pktin->type == SSH1_SMSG_SUCCESS) {
+ crReturnV;
+ if (pktin) {
+ if (pktin->type == SSH1_SMSG_SUCCESS) {
/* may be from EXEC_SHELL on some servers */
} else if (pktin->type == SSH1_SMSG_FAILURE) {
/* may be from EXEC_SHELL on some servers
* if no pty is available or in other odd cases. Ignore */
- } else if (pktin->type == SSH1_SMSG_EXIT_STATUS) {
- char buf[100];
- ssh->exitcode = ssh_pkt_getuint32(pktin);
- sprintf(buf, "Server sent command exit status %d",
- ssh->exitcode);
- logevent(buf);
- send_packet(ssh, SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
- /*
- * In case `helpful' firewalls or proxies tack
- * extra human-readable text on the end of the
- * session which we might mistake for another
- * encrypted packet, we close the session once
- * we've sent EXIT_CONFIRMATION.
- */
- ssh_closing((Plug)ssh, NULL, 0, 0);
- crStopV;
} else {
bombout(("Strange packet received: type %d", pktin->type));
crStopV;
}
}
-void ssh2_msg_channel_window_adjust(Ssh ssh, struct Packet *pktin)
+static void ssh2_msg_channel_window_adjust(Ssh ssh, struct Packet *pktin)
{
unsigned i = ssh_pkt_getuint32(pktin);
struct ssh_channel *c;
c->v.v2.remwindow += ssh_pkt_getuint32(pktin);
}
+static void ssh2_msg_channel_data(Ssh ssh, struct Packet *pktin)
+{
+ char *data;
+ int length;
+ unsigned i = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (!c)
+ return; /* nonexistent channel */
+ if (pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
+ ssh_pkt_getuint32(pktin) != SSH2_EXTENDED_DATA_STDERR)
+ return; /* extended but not stderr */
+ ssh_pkt_getstring(pktin, &data, &length);
+ if (data) {
+ int bufsize = 0;
+ c->v.v2.locwindow -= length;
+ switch (c->type) {
+ case CHAN_MAINSESSION:
+ bufsize =
+ from_backend(ssh->frontend, pktin->type ==
+ SSH2_MSG_CHANNEL_EXTENDED_DATA,
+ data, length);
+ break;
+ case CHAN_X11:
+ bufsize = x11_send(c->u.x11.s, data, length);
+ break;
+ case CHAN_SOCKDATA:
+ bufsize = pfd_send(c->u.pfd.s, data, length);
+ break;
+ case CHAN_AGENT:
+ while (length > 0) {
+ if (c->u.a.lensofar < 4) {
+ int l = min(4 - c->u.a.lensofar, length);
+ memcpy(c->u.a.msglen + c->u.a.lensofar,
+ data, l);
+ data += l;
+ length -= l;
+ c->u.a.lensofar += l;
+ }
+ if (c->u.a.lensofar == 4) {
+ c->u.a.totallen =
+ 4 + GET_32BIT(c->u.a.msglen);
+ c->u.a.message = snewn(c->u.a.totallen,
+ unsigned char);
+ memcpy(c->u.a.message, c->u.a.msglen, 4);
+ }
+ if (c->u.a.lensofar >= 4 && length > 0) {
+ int l =
+ min(c->u.a.totallen - c->u.a.lensofar,
+ length);
+ memcpy(c->u.a.message + c->u.a.lensofar,
+ data, l);
+ data += l;
+ length -= l;
+ c->u.a.lensofar += l;
+ }
+ if (c->u.a.lensofar == c->u.a.totallen) {
+ void *reply;
+ int replylen;
+ if (agent_query(c->u.a.message,
+ c->u.a.totallen,
+ &reply, &replylen,
+ ssh_agentf_callback, c))
+ ssh_agentf_callback(c, reply, replylen);
+ sfree(c->u.a.message);
+ c->u.a.lensofar = 0;
+ }
+ }
+ bufsize = 0;
+ break;
+ }
+ /*
+ * If we are not buffering too much data,
+ * enlarge the window again at the remote side.
+ */
+ if (bufsize < OUR_V2_WINSIZE)
+ ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
+ }
+}
+
+static void ssh2_msg_channel_eof(Ssh ssh, struct Packet *pktin)
+{
+ unsigned i = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (!c)
+ return; /* nonexistent channel */
+
+ if (c->type == CHAN_X11) {
+ /*
+ * Remote EOF on an X11 channel means we should
+ * wrap up and close the channel ourselves.
+ */
+ x11_close(c->u.x11.s);
+ sshfwd_close(c);
+ } else if (c->type == CHAN_AGENT) {
+ sshfwd_close(c);
+ } else if (c->type == CHAN_SOCKDATA) {
+ pfd_close(c->u.pfd.s);
+ sshfwd_close(c);
+ }
+}
+
+static void ssh2_msg_channel_close(Ssh ssh, struct Packet *pktin)
+{
+ unsigned i = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+ struct Packet *pktout;
+
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (!c || ((int)c->remoteid) == -1) {
+ bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
+ c ? "half-open" : "nonexistent", i));
+ return;
+ }
+ /* Do pre-close processing on the channel. */
+ switch (c->type) {
+ case CHAN_MAINSESSION:
+ ssh->mainchan = NULL;
+ update_specials_menu(ssh->frontend);
+ break;
+ case CHAN_X11:
+ if (c->u.x11.s != NULL)
+ x11_close(c->u.x11.s);
+ sshfwd_close(c);
+ break;
+ case CHAN_AGENT:
+ sshfwd_close(c);
+ break;
+ case CHAN_SOCKDATA:
+ if (c->u.pfd.s != NULL)
+ pfd_close(c->u.pfd.s);
+ sshfwd_close(c);
+ break;
+ }
+ if (c->closes == 0) {
+ pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
+ ssh2_pkt_adduint32(pktout, c->remoteid);
+ ssh2_pkt_send(ssh, pktout);
+ }
+ del234(ssh->channels, c);
+ bufchain_clear(&c->v.v2.outbuffer);
+ sfree(c);
+
+ /*
+ * See if that was the last channel left open.
+ * (This is only our termination condition if we're
+ * not running in -N mode.)
+ */
+ if (!ssh->cfg.ssh_no_shell && count234(ssh->channels) == 0) {
+ logevent("All channels closed. Disconnecting");
+#if 0
+ /*
+ * We used to send SSH_MSG_DISCONNECT here,
+ * because I'd believed that _every_ conforming
+ * SSH2 connection had to end with a disconnect
+ * being sent by at least one side; apparently
+ * I was wrong and it's perfectly OK to
+ * unceremoniously slam the connection shut
+ * when you're done, and indeed OpenSSH feels
+ * this is more polite than sending a
+ * DISCONNECT. So now we don't.
+ */
+ s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
+ ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
+ ssh2_pkt_addstring(s->pktout, "All open channels closed");
+ ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
+ ssh2_pkt_send_noqueue(ssh, s->pktout);
+#endif
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ }
+}
+
+static void ssh2_msg_channel_open_confirmation(Ssh ssh, struct Packet *pktin)
+{
+ unsigned i = ssh_pkt_getuint32(pktin);
+ struct ssh_channel *c;
+ struct Packet *pktout;
+
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (!c)
+ return; /* nonexistent channel */
+ if (c->type != CHAN_SOCKDATA_DORMANT)
+ return; /* dunno why they're confirming this */
+ c->remoteid = ssh_pkt_getuint32(pktin);
+ c->type = CHAN_SOCKDATA;
+ c->v.v2.remwindow = ssh_pkt_getuint32(pktin);
+ c->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
+ if (c->u.pfd.s)
+ pfd_confirm(c->u.pfd.s);
+ if (c->closes) {
+ /*
+ * We have a pending close on this channel,
+ * which we decided on before the server acked
+ * the channel open. So now we know the
+ * remoteid, we can close it again.
+ */
+ pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
+ ssh2_pkt_adduint32(pktout, c->remoteid);
+ ssh2_pkt_send(ssh, pktout);
+ }
+}
+
+static void ssh2_msg_channel_open_failure(Ssh ssh, struct Packet *pktin)
+{
+ static const char *const reasons[] = {
+ "<unknown reason code>",
+ "Administratively prohibited",
+ "Connect failed",
+ "Unknown channel type",
+ "Resource shortage",
+ };
+ unsigned i = ssh_pkt_getuint32(pktin);
+ unsigned reason_code;
+ char *reason_string;
+ int reason_length;
+ char *message;
+ struct ssh_channel *c;
+ c = find234(ssh->channels, &i, ssh_channelfind);
+ if (!c)
+ return; /* nonexistent channel */
+ if (c->type != CHAN_SOCKDATA_DORMANT)
+ return; /* dunno why they're failing this */
+
+ reason_code = ssh_pkt_getuint32(pktin);
+ if (reason_code >= lenof(reasons))
+ reason_code = 0; /* ensure reasons[reason_code] in range */
+ ssh_pkt_getstring(pktin, &reason_string, &reason_length);
+ message = dupprintf("Forwarded connection refused by"
+ " server: %s [%.*s]", reasons[reason_code],
+ reason_length, reason_string);
+ logevent(message);
+ sfree(message);
+
+ pfd_close(c->u.pfd.s);
+
+ del234(ssh->channels, c);
+ sfree(c);
+}
+
+static void ssh2_msg_channel_request(Ssh ssh, struct Packet *pktin)
+{
+ unsigned localid;
+ char *type;
+ int typelen, want_reply;
+ int reply = SSH2_MSG_CHANNEL_FAILURE; /* default */
+ struct ssh_channel *c;
+ struct Packet *pktout;
+
+ localid = ssh_pkt_getuint32(pktin);
+ ssh_pkt_getstring(pktin, &type, &typelen);
+ want_reply = ssh2_pkt_getbool(pktin);
+
+ /*
+ * First, check that the channel exists. Otherwise,
+ * we can instantly disconnect with a rude message.
+ */
+ c = find234(ssh->channels, &localid, ssh_channelfind);
+ if (!c) {
+ char buf[80];
+ sprintf(buf, "Received channel request for nonexistent"
+ " channel %d", localid);
+ logevent(buf);
+ pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
+ ssh2_pkt_adduint32(pktout, SSH2_DISCONNECT_BY_APPLICATION);
+ ssh2_pkt_addstring(pktout, buf);
+ ssh2_pkt_addstring(pktout, "en"); /* language tag */
+ ssh2_pkt_send_noqueue(ssh, pktout);
+ connection_fatal(ssh->frontend, "%s", buf);
+ ssh_closing((Plug)ssh, NULL, 0, 0);
+ return;
+ }
+
+ /*
+ * Having got the channel number, we now look at
+ * the request type string to see if it's something
+ * we recognise.
+ */
+ if (c == ssh->mainchan) {
+ /*
+ * We recognise "exit-status" and "exit-signal" on
+ * the primary channel.
+ */
+ if (typelen == 11 &&
+ !memcmp(type, "exit-status", 11)) {
+
+ ssh->exitcode = ssh_pkt_getuint32(pktin);
+ logeventf(ssh, "Server sent command exit status %d",
+ ssh->exitcode);
+ reply = SSH2_MSG_CHANNEL_SUCCESS;
+
+ } else if (typelen == 11 &&
+ !memcmp(type, "exit-signal", 11)) {
+
+ int is_plausible = TRUE, is_int = FALSE;
+ char *fmt_sig = "", *fmt_msg = "";
+ char *msg;
+ int msglen = 0, core = FALSE;
+ /* ICK: older versions of OpenSSH (e.g. 3.4p1)
+ * provide an `int' for the signal, despite its
+ * having been a `string' in the drafts since at
+ * least 2001. (Fixed in session.c 1.147.) Try to
+ * infer which we can safely parse it as. */
+ {
+ unsigned char *p = pktin->body +
+ pktin->savedpos;
+ long len = pktin->length - pktin->savedpos;
+ unsigned long num = GET_32BIT(p); /* what is it? */
+ /* If it's 0, it hardly matters; assume string */
+ if (num == 0) {
+ is_int = FALSE;
+ } else {
+ int maybe_int = FALSE, maybe_str = FALSE;
+#define CHECK_HYPOTHESIS(offset, result) \
+ do { \
+ long q = offset; \
+ if (q >= 0 && q+4 <= len) { \
+ q = q + 4 + GET_32BIT(p+q); \
+ if (q >= 0 && q+4 <= len && \
+ (q = q + 4 + GET_32BIT(p+q)) && q == len) \
+ result = TRUE; \
+ } \
+ } while(0)
+ CHECK_HYPOTHESIS(4+1, maybe_int);
+ CHECK_HYPOTHESIS(4+num+1, maybe_str);
+#undef CHECK_HYPOTHESIS
+ if (maybe_int && !maybe_str)
+ is_int = TRUE;
+ else if (!maybe_int && maybe_str)
+ is_int = FALSE;
+ else
+ /* Crikey. Either or neither. Panic. */
+ is_plausible = FALSE;
+ }
+ }
+ if (is_plausible) {
+ if (is_int) {
+ /* Old non-standard OpenSSH. */
+ int signum = ssh_pkt_getuint32(pktin);
+ fmt_sig = dupprintf(" %d", signum);
+ } else {
+ /* As per the drafts. */
+ char *sig;
+ int siglen;
+ ssh_pkt_getstring(pktin, &sig, &siglen);
+ /* Signal name isn't supposed to be blank, but
+ * let's cope gracefully if it is. */
+ if (siglen) {
+ fmt_sig = dupprintf(" \"%.*s\"",
+ siglen, sig);
+ }
+ }
+ core = ssh2_pkt_getbool(pktin);
+ ssh_pkt_getstring(pktin, &msg, &msglen);
+ if (msglen) {
+ fmt_msg = dupprintf(" (\"%.*s\")", msglen, msg);
+ }
+ /* ignore lang tag */
+ } /* else don't attempt to parse */
+ logeventf(ssh, "Server exited on signal%s%s%s",
+ fmt_sig, core ? " (core dumped)" : "",
+ fmt_msg);
+ if (*fmt_sig) sfree(fmt_sig);
+ if (*fmt_msg) sfree(fmt_msg);
+ reply = SSH2_MSG_CHANNEL_SUCCESS;
+
+ }
+ } else {
+ /*
+ * This is a channel request we don't know
+ * about, so we now either ignore the request
+ * or respond with CHANNEL_FAILURE, depending
+ * on want_reply.
+ */
+ reply = SSH2_MSG_CHANNEL_FAILURE;
+ }
+ if (want_reply) {
+ pktout = ssh2_pkt_init(reply);
+ ssh2_pkt_adduint32(pktout, c->remoteid);
+ ssh2_pkt_send(ssh, pktout);
+ }
+}
+
+static void ssh2_msg_global_request(Ssh ssh, struct Packet *pktin)
+{
+ char *type;
+ int typelen, want_reply;
+ struct Packet *pktout;
+
+ ssh_pkt_getstring(pktin, &type, &typelen);
+ want_reply = ssh2_pkt_getbool(pktin);
+
+ /*
+ * We currently don't support any global requests
+ * at all, so we either ignore the request or
+ * respond with REQUEST_FAILURE, depending on
+ * want_reply.
+ */
+ if (want_reply) {
+ pktout = ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE);
+ ssh2_pkt_send(ssh, pktout);
+ }
+}
+
+static void ssh2_msg_channel_open(Ssh ssh, struct Packet *pktin)
+{
+ char *type;
+ int typelen;
+ char *peeraddr;
+ int peeraddrlen;
+ int peerport;
+ char *error = NULL;
+ struct ssh_channel *c;
+ unsigned remid, winsize, pktsize;
+ struct Packet *pktout;
+
+ ssh_pkt_getstring(pktin, &type, &typelen);
+ c = snew(struct ssh_channel);
+ c->ssh = ssh;
+
+ remid = ssh_pkt_getuint32(pktin);
+ winsize = ssh_pkt_getuint32(pktin);
+ pktsize = ssh_pkt_getuint32(pktin);
+
+ if (typelen == 3 && !memcmp(type, "x11", 3)) {
+ char *addrstr;
+
+ ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
+ addrstr = snewn(peeraddrlen+1, char);
+ memcpy(addrstr, peeraddr, peeraddrlen);
+ addrstr[peeraddrlen] = '\0';
+ peerport = ssh_pkt_getuint32(pktin);
+
+ logeventf(ssh, "Received X11 connect request from %s:%d",
+ addrstr, peerport);
+
+ if (!ssh->X11_fwd_enabled)
+ error = "X11 forwarding is not enabled";
+ else if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
+ ssh->x11auth, addrstr, peerport,
+ &ssh->cfg) != NULL) {
+ error = "Unable to open an X11 connection";
+ } else {
+ logevent("Opening X11 forward connection succeeded");
+ c->type = CHAN_X11;
+ }
+
+ sfree(addrstr);
+ } else if (typelen == 15 &&
+ !memcmp(type, "forwarded-tcpip", 15)) {
+ struct ssh_rportfwd pf, *realpf;
+ char *dummy;
+ int dummylen;
+ ssh_pkt_getstring(pktin, &dummy, &dummylen);/* skip address */
+ pf.sport = ssh_pkt_getuint32(pktin);
+ ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
+ peerport = ssh_pkt_getuint32(pktin);
+ realpf = find234(ssh->rportfwds, &pf, NULL);
+ logeventf(ssh, "Received remote port %d open request "
+ "from %s:%d", pf.sport, peeraddr, peerport);
+ if (realpf == NULL) {
+ error = "Remote port is not recognised";
+ } else {
+ const char *e = pfd_newconnect(&c->u.pfd.s,
+ realpf->dhost,
+ realpf->dport, c,
+ &ssh->cfg);
+ logeventf(ssh, "Attempting to forward remote port to "
+ "%s:%d", realpf->dhost, realpf->dport);
+ if (e != NULL) {
+ logeventf(ssh, "Port open failed: %s", e);
+ error = "Port open failed";
+ } else {
+ logevent("Forwarded port opened successfully");
+ c->type = CHAN_SOCKDATA;
+ }
+ }
+ } else if (typelen == 22 &&
+ !memcmp(type, "auth-agent@openssh.com", 3)) {
+ if (!ssh->agentfwd_enabled)
+ error = "Agent forwarding is not enabled";
+ else {
+ c->type = CHAN_AGENT; /* identify channel type */
+ c->u.a.lensofar = 0;
+ }
+ } else {
+ error = "Unsupported channel type requested";
+ }
+
+ c->remoteid = remid;
+ if (error) {
+ pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE);
+ ssh2_pkt_adduint32(pktout, c->remoteid);
+ ssh2_pkt_adduint32(pktout, SSH2_OPEN_CONNECT_FAILED);
+ ssh2_pkt_addstring(pktout, error);
+ ssh2_pkt_addstring(pktout, "en"); /* language tag */
+ ssh2_pkt_send(ssh, pktout);
+ logeventf(ssh, "Rejected channel open: %s", error);
+ sfree(c);
+ } else {
+ c->localid = alloc_channel_id(ssh);
+ c->closes = 0;
+ c->v.v2.locwindow = OUR_V2_WINSIZE;
+ c->v.v2.remwindow = winsize;
+ c->v.v2.remmaxpkt = pktsize;
+ bufchain_init(&c->v.v2.outbuffer);
+ add234(ssh->channels, c);
+ pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
+ ssh2_pkt_adduint32(pktout, c->remoteid);
+ ssh2_pkt_adduint32(pktout, c->localid);
+ ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);
+ ssh2_pkt_adduint32(pktout, 0x4000UL); /* our max pkt size */
+ ssh2_pkt_send(ssh, pktout);
+ }
+}
+
/*
* Handle the SSH2 userauth and connection layers.
*/
*/
ssh->packet_dispatch[SSH2_MSG_CHANNEL_WINDOW_ADJUST] =
ssh2_msg_channel_window_adjust;
+ ssh->packet_dispatch[SSH2_MSG_GLOBAL_REQUEST] =
+ ssh2_msg_global_request;
/*
* Create the main session channel.
ssh->mainchan = NULL;
/*
+ * Now we have a channel, make dispatch table entries for
+ * general channel-based messages.
+ */
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_DATA] =
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_EXTENDED_DATA] =
+ ssh2_msg_channel_data;
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_EOF] = ssh2_msg_channel_eof;
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_CLOSE] = ssh2_msg_channel_close;
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION] =
+ ssh2_msg_channel_open_confirmation;
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_FAILURE] =
+ ssh2_msg_channel_open_failure;
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_REQUEST] =
+ ssh2_msg_channel_request;
+ ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN] =
+ ssh2_msg_channel_open;
+
+ /*
* Potentially enable X11 forwarding.
*/
if (ssh->mainchan && ssh->cfg.x11_forward) {
crReturnV;
s->try_send = FALSE;
if (pktin) {
- if (pktin->type == SSH2_MSG_CHANNEL_DATA ||
- pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
- char *data;
- int length;
- unsigned i = ssh_pkt_getuint32(pktin);
- struct ssh_channel *c;
- c = find234(ssh->channels, &i, ssh_channelfind);
- if (!c)
- continue; /* nonexistent channel */
- if (pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
- ssh_pkt_getuint32(pktin) != SSH2_EXTENDED_DATA_STDERR)
- continue; /* extended but not stderr */
- ssh_pkt_getstring(pktin, &data, &length);
- if (data) {
- int bufsize = 0;
- c->v.v2.locwindow -= length;
- switch (c->type) {
- case CHAN_MAINSESSION:
- bufsize =
- from_backend(ssh->frontend, pktin->type ==
- SSH2_MSG_CHANNEL_EXTENDED_DATA,
- data, length);
- break;
- case CHAN_X11:
- bufsize = x11_send(c->u.x11.s, data, length);
- break;
- case CHAN_SOCKDATA:
- bufsize = pfd_send(c->u.pfd.s, data, length);
- break;
- case CHAN_AGENT:
- while (length > 0) {
- if (c->u.a.lensofar < 4) {
- int l = min(4 - c->u.a.lensofar, length);
- memcpy(c->u.a.msglen + c->u.a.lensofar,
- data, l);
- data += l;
- length -= l;
- c->u.a.lensofar += l;
- }
- if (c->u.a.lensofar == 4) {
- c->u.a.totallen =
- 4 + GET_32BIT(c->u.a.msglen);
- c->u.a.message = snewn(c->u.a.totallen,
- unsigned char);
- memcpy(c->u.a.message, c->u.a.msglen, 4);
- }
- if (c->u.a.lensofar >= 4 && length > 0) {
- int l =
- min(c->u.a.totallen - c->u.a.lensofar,
- length);
- memcpy(c->u.a.message + c->u.a.lensofar,
- data, l);
- data += l;
- length -= l;
- c->u.a.lensofar += l;
- }
- if (c->u.a.lensofar == c->u.a.totallen) {
- void *reply;
- int replylen;
- if (agent_query(c->u.a.message,
- c->u.a.totallen,
- &reply, &replylen,
- ssh_agentf_callback, c))
- ssh_agentf_callback(c, reply, replylen);
- sfree(c->u.a.message);
- c->u.a.lensofar = 0;
- }
- }
- bufsize = 0;
- break;
- }
- /*
- * If we are not buffering too much data,
- * enlarge the window again at the remote side.
- */
- if (bufsize < OUR_V2_WINSIZE)
- ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
- }
- } else if (pktin->type == SSH2_MSG_CHANNEL_EOF) {
- unsigned i = ssh_pkt_getuint32(pktin);
- struct ssh_channel *c;
-
- c = find234(ssh->channels, &i, ssh_channelfind);
- if (!c)
- continue; /* nonexistent channel */
-
- if (c->type == CHAN_X11) {
- /*
- * Remote EOF on an X11 channel means we should
- * wrap up and close the channel ourselves.
- */
- x11_close(c->u.x11.s);
- sshfwd_close(c);
- } else if (c->type == CHAN_AGENT) {
- sshfwd_close(c);
- } else if (c->type == CHAN_SOCKDATA) {
- pfd_close(c->u.pfd.s);
- sshfwd_close(c);
- }
- } else if (pktin->type == SSH2_MSG_CHANNEL_CLOSE) {
- unsigned i = ssh_pkt_getuint32(pktin);
- struct ssh_channel *c;
-
- c = find234(ssh->channels, &i, ssh_channelfind);
- if (!c || ((int)c->remoteid) == -1) {
- bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
- c ? "half-open" : "nonexistent", i));
- crStopV;
- }
- /* Do pre-close processing on the channel. */
- switch (c->type) {
- case CHAN_MAINSESSION:
- ssh->mainchan = NULL;
- update_specials_menu(ssh->frontend);
- break;
- case CHAN_X11:
- if (c->u.x11.s != NULL)
- x11_close(c->u.x11.s);
- sshfwd_close(c);
- break;
- case CHAN_AGENT:
- sshfwd_close(c);
- break;
- case CHAN_SOCKDATA:
- if (c->u.pfd.s != NULL)
- pfd_close(c->u.pfd.s);
- sshfwd_close(c);
- break;
- }
- if (c->closes == 0) {
- s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
- ssh2_pkt_adduint32(s->pktout, c->remoteid);
- ssh2_pkt_send(ssh, s->pktout);
- }
- del234(ssh->channels, c);
- bufchain_clear(&c->v.v2.outbuffer);
- sfree(c);
-
- /*
- * See if that was the last channel left open.
- * (This is only our termination condition if we're
- * not running in -N mode.)
- */
- if (!ssh->cfg.ssh_no_shell && count234(ssh->channels) == 0) {
- logevent("All channels closed. Disconnecting");
-#if 0
- /*
- * We used to send SSH_MSG_DISCONNECT here,
- * because I'd believed that _every_ conforming
- * SSH2 connection had to end with a disconnect
- * being sent by at least one side; apparently
- * I was wrong and it's perfectly OK to
- * unceremoniously slam the connection shut
- * when you're done, and indeed OpenSSH feels
- * this is more polite than sending a
- * DISCONNECT. So now we don't.
- */
- s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
- ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
- ssh2_pkt_addstring(s->pktout, "All open channels closed");
- ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
- ssh2_pkt_send_noqueue(ssh, s->pktout);
-#endif
- ssh_closing((Plug)ssh, NULL, 0, 0);
- crStopV;
- }
- continue; /* remote sends close; ignore (FIXME) */
- } else if (pktin->type == SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
- unsigned i = ssh_pkt_getuint32(pktin);
- struct ssh_channel *c;
- c = find234(ssh->channels, &i, ssh_channelfind);
- if (!c)
- continue; /* nonexistent channel */
- if (c->type != CHAN_SOCKDATA_DORMANT)
- continue; /* dunno why they're confirming this */
- c->remoteid = ssh_pkt_getuint32(pktin);
- c->type = CHAN_SOCKDATA;
- c->v.v2.remwindow = ssh_pkt_getuint32(pktin);
- c->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
- if (c->u.pfd.s)
- pfd_confirm(c->u.pfd.s);
- if (c->closes) {
- /*
- * We have a pending close on this channel,
- * which we decided on before the server acked
- * the channel open. So now we know the
- * remoteid, we can close it again.
- */
- s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
- ssh2_pkt_adduint32(s->pktout, c->remoteid);
- ssh2_pkt_send(ssh, s->pktout);
- }
- } else if (pktin->type == SSH2_MSG_CHANNEL_OPEN_FAILURE) {
- static const char *const reasons[] = {
- "<unknown reason code>",
- "Administratively prohibited",
- "Connect failed",
- "Unknown channel type",
- "Resource shortage",
- };
- unsigned i = ssh_pkt_getuint32(pktin);
- unsigned reason_code;
- char *reason_string;
- int reason_length;
- char *message;
- struct ssh_channel *c;
- c = find234(ssh->channels, &i, ssh_channelfind);
- if (!c)
- continue; /* nonexistent channel */
- if (c->type != CHAN_SOCKDATA_DORMANT)
- continue; /* dunno why they're failing this */
-
- reason_code = ssh_pkt_getuint32(pktin);
- if (reason_code >= lenof(reasons))
- reason_code = 0; /* ensure reasons[reason_code] in range */
- ssh_pkt_getstring(pktin, &reason_string, &reason_length);
- message = dupprintf("Forwarded connection refused by"
- " server: %s [%.*s]", reasons[reason_code],
- reason_length, reason_string);
- logevent(message);
- sfree(message);
-
- pfd_close(c->u.pfd.s);
-
- del234(ssh->channels, c);
- sfree(c);
- } else if (pktin->type == SSH2_MSG_CHANNEL_REQUEST) {
- unsigned localid;
- char *type;
- int typelen, want_reply;
- int reply = SSH2_MSG_CHANNEL_FAILURE; /* default */
- struct ssh_channel *c;
-
- localid = ssh_pkt_getuint32(pktin);
- ssh_pkt_getstring(pktin, &type, &typelen);
- want_reply = ssh2_pkt_getbool(pktin);
-
- /*
- * First, check that the channel exists. Otherwise,
- * we can instantly disconnect with a rude message.
- */
- c = find234(ssh->channels, &localid, ssh_channelfind);
- if (!c) {
- char buf[80];
- sprintf(buf, "Received channel request for nonexistent"
- " channel %d", localid);
- logevent(buf);
- s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
- ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
- ssh2_pkt_addstring(s->pktout, buf);
- ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
- ssh2_pkt_send_noqueue(ssh, s->pktout);
- connection_fatal(ssh->frontend, "%s", buf);
- ssh_closing((Plug)ssh, NULL, 0, 0);
- crStopV;
- }
-
- /*
- * Having got the channel number, we now look at
- * the request type string to see if it's something
- * we recognise.
- */
- if (c == ssh->mainchan) {
- /*
- * We recognise "exit-status" and "exit-signal" on
- * the primary channel.
- */
- if (typelen == 11 &&
- !memcmp(type, "exit-status", 11)) {
-
- ssh->exitcode = ssh_pkt_getuint32(pktin);
- logeventf(ssh, "Server sent command exit status %d",
- ssh->exitcode);
- reply = SSH2_MSG_CHANNEL_SUCCESS;
-
- } else if (typelen == 11 &&
- !memcmp(type, "exit-signal", 11)) {
-
- int is_plausible = TRUE, is_int = FALSE;
- char *fmt_sig = "", *fmt_msg = "";
- char *msg;
- int msglen = 0, core = FALSE;
- /* ICK: older versions of OpenSSH (e.g. 3.4p1)
- * provide an `int' for the signal, despite its
- * having been a `string' in the drafts since at
- * least 2001. (Fixed in session.c 1.147.) Try to
- * infer which we can safely parse it as. */
- {
- unsigned char *p = pktin->body +
- pktin->savedpos;
- long len = pktin->length - pktin->savedpos;
- unsigned long num = GET_32BIT(p); /* what is it? */
- /* If it's 0, it hardly matters; assume string */
- if (num == 0) {
- is_int = FALSE;
- } else {
- int maybe_int = FALSE, maybe_str = FALSE;
-#define CHECK_HYPOTHESIS(offset, result) \
- do { \
- long q = offset; \
- if (q >= 0 && q+4 <= len) { \
- q = q + 4 + GET_32BIT(p+q); \
- if (q >= 0 && q+4 <= len && \
- (q = q + 4 + GET_32BIT(p+q)) && q == len) \
- result = TRUE; \
- } \
- } while(0)
- CHECK_HYPOTHESIS(4+1, maybe_int);
- CHECK_HYPOTHESIS(4+num+1, maybe_str);
-#undef CHECK_HYPOTHESIS
- if (maybe_int && !maybe_str)
- is_int = TRUE;
- else if (!maybe_int && maybe_str)
- is_int = FALSE;
- else
- /* Crikey. Either or neither. Panic. */
- is_plausible = FALSE;
- }
- }
- if (is_plausible) {
- if (is_int) {
- /* Old non-standard OpenSSH. */
- int signum = ssh_pkt_getuint32(pktin);
- fmt_sig = dupprintf(" %d", signum);
- } else {
- /* As per the drafts. */
- char *sig;
- int siglen;
- ssh_pkt_getstring(pktin, &sig, &siglen);
- /* Signal name isn't supposed to be blank, but
- * let's cope gracefully if it is. */
- if (siglen) {
- fmt_sig = dupprintf(" \"%.*s\"",
- siglen, sig);
- }
- }
- core = ssh2_pkt_getbool(pktin);
- ssh_pkt_getstring(pktin, &msg, &msglen);
- if (msglen) {
- fmt_msg = dupprintf(" (\"%.*s\")", msglen, msg);
- }
- /* ignore lang tag */
- } /* else don't attempt to parse */
- logeventf(ssh, "Server exited on signal%s%s%s",
- fmt_sig, core ? " (core dumped)" : "",
- fmt_msg);
- if (*fmt_sig) sfree(fmt_sig);
- if (*fmt_msg) sfree(fmt_msg);
- reply = SSH2_MSG_CHANNEL_SUCCESS;
- }
- } else {
- /*
- * This is a channel request we don't know
- * about, so we now either ignore the request
- * or respond with CHANNEL_FAILURE, depending
- * on want_reply.
- */
- reply = SSH2_MSG_CHANNEL_FAILURE;
- }
- if (want_reply) {
- s->pktout = ssh2_pkt_init(reply);
- ssh2_pkt_adduint32(s->pktout, c->remoteid);
- ssh2_pkt_send(ssh, s->pktout);
- }
- } else if (pktin->type == SSH2_MSG_GLOBAL_REQUEST) {
- char *type;
- int typelen, want_reply;
-
- ssh_pkt_getstring(pktin, &type, &typelen);
- want_reply = ssh2_pkt_getbool(pktin);
-
- /*
- * We currently don't support any global requests
- * at all, so we either ignore the request or
- * respond with REQUEST_FAILURE, depending on
- * want_reply.
- */
- if (want_reply) {
- s->pktout = ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE);
- ssh2_pkt_send(ssh, s->pktout);
- }
- } else if (pktin->type == SSH2_MSG_CHANNEL_OPEN) {
- char *type;
- int typelen;
- char *peeraddr;
- int peeraddrlen;
- int peerport;
- char *error = NULL;
- struct ssh_channel *c;
- unsigned remid, winsize, pktsize;
- ssh_pkt_getstring(pktin, &type, &typelen);
- c = snew(struct ssh_channel);
- c->ssh = ssh;
-
- remid = ssh_pkt_getuint32(pktin);
- winsize = ssh_pkt_getuint32(pktin);
- pktsize = ssh_pkt_getuint32(pktin);
-
- if (typelen == 3 && !memcmp(type, "x11", 3)) {
- char *addrstr;
-
- ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
- addrstr = snewn(peeraddrlen+1, char);
- memcpy(addrstr, peeraddr, peeraddrlen);
- addrstr[peeraddrlen] = '\0';
- peerport = ssh_pkt_getuint32(pktin);
-
- logeventf(ssh, "Received X11 connect request from %s:%d",
- addrstr, peerport);
-
- if (!ssh->X11_fwd_enabled)
- error = "X11 forwarding is not enabled";
- else if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
- ssh->x11auth, addrstr, peerport,
- &ssh->cfg) != NULL) {
- error = "Unable to open an X11 connection";
- } else {
- logevent("Opening X11 forward connection succeeded");
- c->type = CHAN_X11;
- }
-
- sfree(addrstr);
- } else if (typelen == 15 &&
- !memcmp(type, "forwarded-tcpip", 15)) {
- struct ssh_rportfwd pf, *realpf;
- char *dummy;
- int dummylen;
- ssh_pkt_getstring(pktin, &dummy, &dummylen);/* skip address */
- pf.sport = ssh_pkt_getuint32(pktin);
- ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
- peerport = ssh_pkt_getuint32(pktin);
- realpf = find234(ssh->rportfwds, &pf, NULL);
- logeventf(ssh, "Received remote port %d open request "
- "from %s:%d", pf.sport, peeraddr, peerport);
- if (realpf == NULL) {
- error = "Remote port is not recognised";
- } else {
- const char *e = pfd_newconnect(&c->u.pfd.s,
- realpf->dhost,
- realpf->dport, c,
- &ssh->cfg);
- logeventf(ssh, "Attempting to forward remote port to "
- "%s:%d", realpf->dhost, realpf->dport);
- if (e != NULL) {
- logeventf(ssh, "Port open failed: %s", e);
- error = "Port open failed";
- } else {
- logevent("Forwarded port opened successfully");
- c->type = CHAN_SOCKDATA;
- }
- }
- } else if (typelen == 22 &&
- !memcmp(type, "auth-agent@openssh.com", 3)) {
- if (!ssh->agentfwd_enabled)
- error = "Agent forwarding is not enabled";
- else {
- c->type = CHAN_AGENT; /* identify channel type */
- c->u.a.lensofar = 0;
- }
- } else {
- error = "Unsupported channel type requested";
- }
+ /*
+ * _All_ the connection-layer packets we expect to
+ * receive are now handled by the dispatch table.
+ * Anything that reaches here must be bogus.
+ */
- c->remoteid = remid;
- if (error) {
- s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE);
- ssh2_pkt_adduint32(s->pktout, c->remoteid);
- ssh2_pkt_adduint32(s->pktout, SSH2_OPEN_CONNECT_FAILED);
- ssh2_pkt_addstring(s->pktout, error);
- ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
- ssh2_pkt_send(ssh, s->pktout);
- logeventf(ssh, "Rejected channel open: %s", error);
- sfree(c);
- } else {
- c->localid = alloc_channel_id(ssh);
- c->closes = 0;
- c->v.v2.locwindow = OUR_V2_WINSIZE;
- c->v.v2.remwindow = winsize;
- c->v.v2.remmaxpkt = pktsize;
- bufchain_init(&c->v.v2.outbuffer);
- add234(ssh->channels, c);
- s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
- ssh2_pkt_adduint32(s->pktout, c->remoteid);
- ssh2_pkt_adduint32(s->pktout, c->localid);
- ssh2_pkt_adduint32(s->pktout, c->v.v2.locwindow);
- ssh2_pkt_adduint32(s->pktout, 0x4000UL); /* our max pkt size */
- ssh2_pkt_send(ssh, s->pktout);
- }
- } else {
- bombout(("Strange packet received: type %d", pktin->type));
- crStopV;
- }
+ bombout(("Strange packet received: type %d", pktin->type));
+ crStopV;
} else if (ssh->mainchan) {
/*
* We have spare data. Add it to the channel buffer.
projects / u / mdw / putty / commitdiff