X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/36f94d1f29f1bad2e8e21fdd6a6d87c898b8b25a..cbe2d68fd7c7c7bac692b3a2d200a5d2429ab201:/ssh.c

diff --git a/ssh.c b/ssh.c
index 4243a049..337cfa8b 100644
--- a/ssh.c
+++ b/ssh.c
@@ -322,6 +322,8 @@ static unsigned char *ssh2_mpint_fmt(Bignum b, int *len);
 static void ssh2_pkt_addmp(Ssh, Bignum b);
 static int ssh2_pkt_construct(Ssh);
 static void ssh2_pkt_send(Ssh);
+static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt);
+static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt);
 
 /*
  * Buffer management constants. There are several of these for
@@ -649,12 +651,18 @@ struct ssh_tag {
      * potentially reconfigure port forwardings etc in mid-session.
      */
     Config cfg;
+
+    /*
+     * Used to transfer data back from async agent callbacks.
+     */
+    void *agent_response;
+    int agent_response_len;
 };
 
 #define logevent(s) logevent(ssh->frontend, s)
 
 /* logevent, only printf-formatted. */
-static void logeventf(Ssh ssh, char *fmt, ...)
+static void logeventf(Ssh ssh, const char *fmt, ...)
 {
     va_list ap;
     char *buf;
@@ -2051,23 +2059,25 @@ static void ssh_do_close(Ssh ssh)
      * Now we must shut down any port and X forwardings going
      * through this connection.
      */
-    for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
-	switch (c->type) {
-	  case CHAN_X11:
-	    x11_close(c->u.x11.s);
-	    break;
-	  case CHAN_SOCKDATA:
-	    pfd_close(c->u.pfd.s);
-	    break;
+    if (ssh->channels) {
+	for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
+	    switch (c->type) {
+	      case CHAN_X11:
+		x11_close(c->u.x11.s);
+		break;
+	      case CHAN_SOCKDATA:
+		pfd_close(c->u.pfd.s);
+		break;
+	    }
+	    del234(ssh->channels, c);
+	    if (ssh->version == 2)
+		bufchain_clear(&c->v.v2.outbuffer);
+	    sfree(c);
 	}
-	del234(ssh->channels, c);
-	if (ssh->version == 2)
-	    bufchain_clear(&c->v.v2.outbuffer);
-	sfree(c);
     }
 }
 
-static int ssh_closing(Plug plug, char *error_msg, int error_code,
+static int ssh_closing(Plug plug, const char *error_msg, int error_code,
 		       int calling_back)
 {
     Ssh ssh = (Ssh) plug;
@@ -2075,7 +2085,7 @@ static int ssh_closing(Plug plug, char *error_msg, int error_code,
     if (error_msg) {
 	/* A socket error has occurred. */
 	logevent(error_msg);
-	connection_fatal(ssh->frontend, error_msg);
+	connection_fatal(ssh->frontend, "%s", error_msg);
     } else {
 	/* Otherwise, the remote side closed the connection normally. */
     }
@@ -2110,8 +2120,8 @@ static void ssh_sent(Plug plug, int bufsize)
  * Also places the canonical host name into `realhost'. It must be
  * freed by the caller.
  */
-static char *connect_to_host(Ssh ssh, char *host, int port,
-			     char **realhost, int nodelay)
+static const char *connect_to_host(Ssh ssh, char *host, int port,
+				   char **realhost, int nodelay)
 {
     static const struct plug_function_table fn_table = {
 	ssh_closing,
@@ -2121,7 +2131,7 @@ static char *connect_to_host(Ssh ssh, char *host, int port,
     };
 
     SockAddr addr;
-    char *err;
+    const char *err;
 
     ssh->savedhost = snewn(1 + strlen(host), char);
     if (!ssh->savedhost)
@@ -2281,6 +2291,44 @@ static int process_userpass_input(Ssh ssh, unsigned char *in, int inlen)
     return 0;
 }
 
+void ssh_agent_callback(void *sshv, void *reply, int replylen)
+{
+    Ssh ssh = (Ssh) sshv;
+
+    ssh->agent_response = reply;
+    ssh->agent_response_len = replylen;
+
+    if (ssh->version == 1)
+	do_ssh1_login(ssh, NULL, -1, 0);
+    else
+	do_ssh2_authconn(ssh, NULL, -1, 0);
+}
+
+void ssh_agentf_callback(void *cv, void *reply, int replylen)
+{
+    struct ssh_channel *c = (struct ssh_channel *)cv;
+    Ssh ssh = c->ssh;
+    void *sentreply = reply;
+
+    if (!sentreply) {
+	/* Fake SSH_AGENT_FAILURE. */
+	sentreply = "\0\0\0\1\5";
+	replylen = 5;
+    }
+    if (ssh->version == 2) {
+	ssh2_add_channel_data(c, sentreply, replylen);
+	ssh2_try_send(c);
+    } else {
+	send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
+		    PKT_INT, c->remoteid,
+		    PKT_INT, replylen,
+		    PKT_DATA, sentreply, replylen,
+		    PKT_END);
+    }
+    if (reply)
+	sfree(reply);
+}
+
 /*
  * Handle the key exchange and user authentication phases.
  */
@@ -2567,7 +2615,19 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 	    /* Request the keys held by the agent. */
 	    PUT_32BIT(s->request, 1);
 	    s->request[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES;
-	    agent_query(s->request, 5, &r, &s->responselen);
+	    if (!agent_query(s->request, 5, &r, &s->responselen,
+			     ssh_agent_callback, ssh)) {
+		do {
+		    crReturn(0);
+		    if (ispkt) {
+			bombout(("Unexpected data from server while waiting"
+				 " for agent response"));
+			crStop(0);
+		    }
+		} while (ispkt || inlen > 0);
+		r = ssh->agent_response;
+		s->responselen = ssh->agent_response_len;
+	    }
 	    s->response = (unsigned char *) r;
 	    if (s->response && s->responselen >= 5 &&
 		s->response[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER) {
@@ -2629,9 +2689,23 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 			memcpy(q, s->session_id, 16);
 			q += 16;
 			PUT_32BIT(q, 1);	/* response format */
-			agent_query(agentreq, len + 4, &vret, &retlen);
+			if (!agent_query(agentreq, len + 4, &vret, &retlen,
+					 ssh_agent_callback, ssh)) {
+			    sfree(agentreq);
+			    do {
+				crReturn(0);
+				if (ispkt) {
+				    bombout(("Unexpected data from server"
+					     " while waiting for agent"
+					     " response"));
+				    crStop(0);
+				}
+			    } while (ispkt || inlen > 0);
+			    vret = ssh->agent_response;
+			    retlen = ssh->agent_response_len;
+			} else
+			    sfree(agentreq);
 			ret = vret;
-			sfree(agentreq);
 			if (ret) {
 			    if (ret[4] == SSH1_AGENT_RSA_RESPONSE) {
 				logevent("Sending Pageant's response");
@@ -3454,7 +3528,8 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		struct ssh_rportfwd pf;
 		int hostsize, port;
 		char host[256], buf[1024];
-		char *p, *h, *e;
+		char *p, *h;
+		const char *e;
 		c = snew(struct ssh_channel);
 		c->ssh = ssh;
 
@@ -3627,25 +3702,13 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 				c->u.a.lensofar += l;
 			    }
 			    if (c->u.a.lensofar == c->u.a.totallen) {
-				void *reply, *sentreply;
+				void *reply;
 				int replylen;
-				agent_query(c->u.a.message,
-					    c->u.a.totallen, &reply,
-					    &replylen);
-				if (reply)
-				    sentreply = reply;
-				else {
-				    /* Fake SSH_AGENT_FAILURE. */
-				    sentreply = "\0\0\0\1\5";
-				    replylen = 5;
-				}
-				send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
-					    PKT_INT, c->remoteid,
-					    PKT_INT, replylen,
-					    PKT_DATA, sentreply, replylen,
-					    PKT_END);
-				if (reply)
-				    sfree(reply);
+				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;
 			    }
@@ -4671,7 +4734,19 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		/* Request the keys held by the agent. */
 		PUT_32BIT(s->request, 1);
 		s->request[4] = SSH2_AGENTC_REQUEST_IDENTITIES;
-		agent_query(s->request, 5, &r, &s->responselen);
+		if (!agent_query(s->request, 5, &r, &s->responselen,
+				 ssh_agent_callback, ssh)) {
+		    do {
+			crReturnV;
+			if (ispkt) {
+			    bombout(("Unexpected data from server while"
+				     " waiting for agent response"));
+			    crStopV;
+			}
+		    } while (ispkt || inlen > 0);
+		    r = ssh->agent_response;
+		    s->responselen = ssh->agent_response_len;
+		}
 		s->response = (unsigned char *) r;
 		if (s->response && s->responselen >= 5 &&
 		    s->response[4] == SSH2_AGENT_IDENTITIES_ANSWER) {
@@ -4775,7 +4850,21 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 			s->q += ssh->pktout.length - 5;
 			/* And finally the (zero) flags word. */
 			PUT_32BIT(s->q, 0);
-			agent_query(s->agentreq, s->len + 4, &vret, &s->retlen);
+			if (!agent_query(s->agentreq, s->len + 4,
+					 &vret, &s->retlen,
+					 ssh_agent_callback, ssh)) {
+			    do {
+				crReturnV;
+				if (ispkt) {
+				    bombout(("Unexpected data from server"
+					     " while waiting for agent"
+					     " response"));
+				    crStopV;
+				}
+			    } while (ispkt || inlen > 0);
+			    vret = ssh->agent_response;
+			    s->retlen = ssh->agent_response_len;
+			}
 			s->ret = vret;
 			sfree(s->agentreq);
 			if (s->ret) {
@@ -5630,22 +5719,13 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 				c->u.a.lensofar += l;
 			    }
 			    if (c->u.a.lensofar == c->u.a.totallen) {
-				void *reply, *sentreply;
+				void *reply;
 				int replylen;
-				agent_query(c->u.a.message,
-					    c->u.a.totallen, &reply,
-					    &replylen);
-				if (reply)
-				    sentreply = reply;
-				else {
-				    /* Fake SSH_AGENT_FAILURE. */
-				    sentreply = "\0\0\0\1\5";
-				    replylen = 5;
-				}
-				ssh2_add_channel_data(c, sentreply, replylen);
-				s->try_send = TRUE;
-				if (reply)
-				    sfree(reply);
+				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;
 			    }
@@ -5921,8 +6001,10 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		    if (realpf == NULL) {
 			error = "Remote port is not recognised";
 		    } else {
-			char *e = pfd_newconnect(&c->u.pfd.s, realpf->dhost,
-						 realpf->dport, c, &ssh->cfg);
+			const char *e = pfd_newconnect(&c->u.pfd.s,
+						       realpf->dhost,
+						       realpf->dport, c,
+						       &ssh->cfg);
 			logeventf(ssh, "Received remote port open request"
 				  " for %s:%d", realpf->dhost, realpf->dport);
 			if (e != NULL) {
@@ -6031,11 +6113,11 @@ static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
  *
  * Returns an error message, or NULL on success.
  */
-static char *ssh_init(void *frontend_handle, void **backend_handle,
-		      Config *cfg,
-		      char *host, int port, char **realhost, int nodelay)
+static const char *ssh_init(void *frontend_handle, void **backend_handle,
+			    Config *cfg,
+			    char *host, int port, char **realhost, int nodelay)
 {
-    char *p;
+    const char *p;
     Ssh ssh;
 
     ssh = snew(struct ssh_tag);