Add a bug-compatibility flag to disable the

[u/mdw/putty] / ssh.c

diff --git a/ssh.c b/ssh.c
index a21bbc7..351003f 100644 (file)
--- a/ssh.c
+++ b/ssh.c
@@ -196,6 +196,7 @@ static const char *const ssh2_disconnect_reasons[] = {
 #define BUG_SSH2_PK_SESSIONID                   128
 #define BUG_SSH2_MAXPKT                                256
 #define BUG_CHOKES_ON_SSH2_IGNORE               512
+#define BUG_CHOKES_ON_WINADJ                   1024
 
 /*
  * Codes for terminal modes.
@@ -558,7 +559,15 @@ enum {                                    /* channel types */
     CHAN_X11,
     CHAN_AGENT,
     CHAN_SOCKDATA,
-    CHAN_SOCKDATA_DORMANT             /* one the remote hasn't confirmed */
+    CHAN_SOCKDATA_DORMANT,            /* one the remote hasn't confirmed */
+    /*
+     * CHAN_ZOMBIE is used to indicate a channel for which we've
+     * already destroyed the local data source: for instance, if a
+     * forwarded port experiences a socket error on the local side, we
+     * immediately destroy its local socket and turn the SSH channel
+     * into CHAN_ZOMBIE.
+     */
+    CHAN_ZOMBIE
 };
 
 /*
@@ -2572,6 +2581,15 @@ static void ssh_detect_bugs(Ssh ssh, char *vstring)
        ssh->remote_bugs |= BUG_CHOKES_ON_SSH2_IGNORE;
        logevent("We believe remote version has SSH-2 ignore bug");
     }
+
+    if (conf_get_int(ssh->conf, CONF_sshbug_winadj) == FORCE_ON) {
+       /*
+        * Servers that don't support our winadj request for one
+        * reason or another. Currently, none detected automatically.
+        */
+       ssh->remote_bugs |= BUG_CHOKES_ON_WINADJ;
+       logevent("We believe remote version has winadj bug");
+    }
 }
 
 /*
@@ -3841,7 +3859,7 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
                ret = loadrsakey(s->keyfile, &s->key, passphrase,
                                 &error);
                if (passphrase) {
-                   memset(passphrase, 0, strlen(passphrase));
+                   smemclr(passphrase, strlen(passphrase));
                    sfree(passphrase);
                }
                if (ret == 1) {
@@ -4250,6 +4268,35 @@ void sshfwd_write_eof(struct ssh_channel *c)
     ssh_channel_try_eof(c);
 }
 
+void sshfwd_unclean_close(struct ssh_channel *c)
+{
+    Ssh ssh = c->ssh;
+    struct Packet *pktout;
+
+    if (ssh->state == SSH_STATE_CLOSED)
+       return;
+
+    if (!(c->closes & CLOSES_SENT_CLOSE)) {
+        pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
+        ssh2_pkt_adduint32(pktout, c->remoteid);
+        ssh2_pkt_send(ssh, pktout);
+        c->closes |= CLOSES_SENT_EOF | CLOSES_SENT_CLOSE;
+    }
+
+    switch (c->type) {
+      case CHAN_X11:
+        x11_close(c->u.x11.s);
+        break;
+      case CHAN_SOCKDATA:
+      case CHAN_SOCKDATA_DORMANT:
+        pfd_close(c->u.pfd.s);
+        break;
+    }
+    c->type = CHAN_ZOMBIE;
+
+    ssh2_channel_check_close(c);
+}
+
 int sshfwd_write(struct ssh_channel *c, char *buf, int len)
 {
     Ssh ssh = c->ssh;
@@ -5741,6 +5788,12 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
                break;
            }
        }
+       if (!ssh->hostkey) {
+           bombout(("Couldn't agree a host key algorithm (available: %s)",
+                    str ? str : "(null)"));
+           crStop(0);
+       }
+
        s->guessok = s->guessok &&
            first_in_commasep_string(hostkey_algs[0]->name, str, len);
        ssh_pkt_getstring(pktin, &str, &len);    /* client->server cipher */
@@ -6251,7 +6304,7 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
        assert(ssh->csmac->len <=
               ssh->kex->hash->hlen * SSH2_MKKEY_ITERS);
        ssh->csmac->setkey(ssh->cs_mac_ctx, keyspace);
-       memset(keyspace, 0, sizeof(keyspace));
+       smemclr(keyspace, sizeof(keyspace));
     }
 
     logeventf(ssh, "Initialised %.200s client->server encryption",
@@ -6317,7 +6370,7 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
        assert(ssh->scmac->len <=
               ssh->kex->hash->hlen * SSH2_MKKEY_ITERS);
        ssh->scmac->setkey(ssh->sc_mac_ctx, keyspace);
-       memset(keyspace, 0, sizeof(keyspace));
+       smemclr(keyspace, sizeof(keyspace));
     }
     logeventf(ssh, "Initialised %.200s server->client encryption",
              ssh->sccipher->text_name);
@@ -6592,7 +6645,8 @@ static void ssh2_set_window(struct ssh_channel *c, int newwin)
         * unexpected CHANNEL_FAILUREs.
         */
        if (newwin == c->v.v2.locmaxwin &&
-           ssh->packet_dispatch[SSH2_MSG_CHANNEL_FAILURE]) {
+           ssh->packet_dispatch[SSH2_MSG_CHANNEL_FAILURE] &&
+            !(ssh->remote_bugs & BUG_CHOKES_ON_WINADJ)) {
            pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
            ssh2_pkt_adduint32(pktout, c->remoteid);
            ssh2_pkt_addstring(pktout, "winadj@putty.projects.tartarus.org");
@@ -6999,7 +7053,7 @@ static void ssh2_msg_channel_close(Ssh ssh, struct Packet *pktin)
         /*
          * Send outgoing EOF.
          */
-        sshfwd_write_eof(ssh->mainchan);
+        sshfwd_write_eof(c);
     }
 
     /*
@@ -8108,7 +8162,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
                    key = ssh2_load_userkey(s->keyfile, passphrase, &error);
                    if (passphrase) {
                        /* burn the evidence */
-                       memset(passphrase, 0, strlen(passphrase));
+                       smemclr(passphrase, strlen(passphrase));
                        sfree(passphrase);
                    }
                    if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
@@ -8687,7 +8741,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
                             */
                            /* burn the evidence */
                            free_prompts(s->cur_prompt);
-                           memset(s->password, 0, strlen(s->password));
+                           smemclr(s->password, strlen(s->password));
                            sfree(s->password);
                            ssh_disconnect(ssh, NULL, "Unable to authenticate",
                                           SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER,
@@ -8703,7 +8757,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
                         * re-enter it if they louse up the new password.)
                         */
                        if (s->cur_prompt->prompts[0]->result[0]) {
-                           memset(s->password, 0, strlen(s->password));
+                           smemclr(s->password, strlen(s->password));
                                /* burn the evidence */
                            sfree(s->password);
                            s->password =
@@ -8770,7 +8824,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
                 * We don't need the old password any more, in any
                 * case. Burn the evidence.
                 */
-               memset(s->password, 0, strlen(s->password));
+               smemclr(s->password, strlen(s->password));
                sfree(s->password);
 
            } else {
@@ -10000,6 +10054,12 @@ static void ssh_unthrottle(void *handle, int bufsize)
            }
        }
     }
+
+    /*
+     * Now process any SSH connection data that was stashed in our
+     * queue while we were frozen.
+     */
+    ssh_process_queued_incoming_data(ssh);
 }
 
 void ssh_send_port_open(void *channel, char *hostname, int port, char *org)