Rename the various ssh2_maybe_setup_* functions to ssh2_setup_*, and
[sgt/putty] / ssh.c
diff --git a/ssh.c b/ssh.c
index bfc10b0..c419a89 100644 (file)
--- a/ssh.c
+++ b/ssh.c
@@ -780,8 +780,8 @@ static unsigned long ssh_pkt_getuint32(struct Packet *pkt);
 static int ssh2_pkt_getbool(struct Packet *pkt);
 static void ssh_pkt_getstring(struct Packet *pkt, char **p, int *length);
 static void ssh2_timer(void *ctx, long now);
-static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
-                            struct Packet *pktin);
+static void do_ssh2_transport(Ssh ssh, void *vin, int inlen,
+                             struct Packet *pktin);
 static void ssh2_msg_unexpected(Ssh ssh, struct Packet *pktin);
 
 struct rdpkt1_state_tag {
@@ -1019,14 +1019,15 @@ static void logeventf(Ssh ssh, const char *fmt, ...)
     sfree(buf);
 }
 
-#define bombout(msg) \
-    do { \
-        char *text = dupprintf msg; \
-       ssh_do_close(ssh, FALSE); \
-        logevent(text); \
-        connection_fatal(ssh->frontend, "%s", text); \
-        sfree(text); \
-    } while (0)
+static void bomb_out(Ssh ssh, char *text)
+{
+    ssh_do_close(ssh, FALSE);
+    logevent(text);
+    connection_fatal(ssh->frontend, "%s", text);
+    sfree(text);
+}
+
+#define bombout(msg) bomb_out(ssh, dupprintf msg)
 
 /* Functions to leave bits out of the SSH packet log file. */
 
@@ -1062,12 +1063,14 @@ static void parse_ttymodes(Ssh ssh,
         * follows it, or 'A' indicating that we should pass the
         * value through from the local environment via get_ttymode.
         */
-       if (val[0] == 'A')
+       if (val[0] == 'A') {
            val = get_ttymode(ssh->frontend, key);
-       else
-           val++;                     /* skip the 'V' */
-       if (val)
-           do_mode(data, key, val);
+           if (val) {
+               do_mode(data, key, val);
+               sfree(val);
+           }
+       } else
+           do_mode(data, key, val + 1);               /* skip the 'V' */
     }
 }
 
@@ -5473,7 +5476,7 @@ static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H, char chr,
 /*
  * Handle the SSH-2 transport layer.
  */
-static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
+static void do_ssh2_transport(Ssh ssh, void *vin, int inlen,
                             struct Packet *pktin)
 {
     unsigned char *in = (unsigned char *)vin;
@@ -5714,7 +5717,7 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
     ssh2_pkt_send_noqueue(ssh, s->pktout);
 
     if (!pktin)
-       crWaitUntil(pktin);
+       crWaitUntilV(pktin);
 
     /*
      * Now examine the other side's KEXINIT to see what we're up
@@ -5726,7 +5729,7 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
 
        if (pktin->type != SSH2_MSG_KEXINIT) {
            bombout(("expected key exchange packet from server"));
-           crStop(0);
+           crStopV;
        }
        ssh->kex = NULL;
        ssh->hostkey = NULL;
@@ -5761,7 +5764,7 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
        if (!ssh->kex) {
            bombout(("Couldn't agree a key exchange algorithm (available: %s)",
                     str ? str : "(null)"));
-           crStop(0);
+           crStopV;
        }
        /*
         * Note that the server's guess is considered wrong if it doesn't match
@@ -5779,7 +5782,7 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
        if (!ssh->hostkey) {
            bombout(("Couldn't agree a host key algorithm (available: %s)",
                     str ? str : "(null)"));
-           crStop(0);
+           crStopV;
        }
 
        s->guessok = s->guessok &&
@@ -5803,7 +5806,7 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
        if (!s->cscipher_tobe) {
            bombout(("Couldn't agree a client-to-server cipher (available: %s)",
                     str ? str : "(null)"));
-           crStop(0);
+           crStopV;
        }
 
        ssh_pkt_getstring(pktin, &str, &len);    /* server->client cipher */
@@ -5825,7 +5828,7 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
        if (!s->sccipher_tobe) {
            bombout(("Couldn't agree a server-to-client cipher (available: %s)",
                     str ? str : "(null)"));
-           crStop(0);
+           crStopV;
        }
 
        ssh_pkt_getstring(pktin, &str, &len);    /* client->server mac */
@@ -5889,11 +5892,11 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
                               ssh_dialog_callback, ssh);
            if (s->dlgret < 0) {
                do {
-                   crReturn(0);
+                   crReturnV;
                    if (pktin) {
                        bombout(("Unexpected data from server while"
                                 " waiting for user response"));
-                       crStop(0);
+                       crStopV;
                    }
                } while (pktin || inlen > 0);
                s->dlgret = ssh->user_response;
@@ -5902,7 +5905,7 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
            if (s->dlgret == 0) {
                ssh_disconnect(ssh, "User aborted at kex warning", NULL,
                               0, TRUE);
-               crStop(0);
+               crStopV;
            }
        }
 
@@ -5914,11 +5917,11 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
                               ssh_dialog_callback, ssh);
            if (s->dlgret < 0) {
                do {
-                   crReturn(0);
+                   crReturnV;
                    if (pktin) {
                        bombout(("Unexpected data from server while"
                                 " waiting for user response"));
-                       crStop(0);
+                       crStopV;
                    }
                } while (pktin || inlen > 0);
                s->dlgret = ssh->user_response;
@@ -5927,7 +5930,7 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
            if (s->dlgret == 0) {
                ssh_disconnect(ssh, "User aborted at cipher warning", NULL,
                               0, TRUE);
-               crStop(0);
+               crStopV;
            }
        }
 
@@ -5939,11 +5942,11 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
                               ssh_dialog_callback, ssh);
            if (s->dlgret < 0) {
                do {
-                   crReturn(0);
+                   crReturnV;
                    if (pktin) {
                        bombout(("Unexpected data from server while"
                                 " waiting for user response"));
-                       crStop(0);
+                       crStopV;
                    }
                } while (pktin || inlen > 0);
                s->dlgret = ssh->user_response;
@@ -5952,7 +5955,7 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
            if (s->dlgret == 0) {
                ssh_disconnect(ssh, "User aborted at cipher warning", NULL,
                               0, TRUE);
-               crStop(0);
+               crStopV;
            }
        }
 
@@ -5967,7 +5970,7 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
                pktin->data + 5, pktin->length - 5);
 
        if (s->ignorepkt) /* first_kex_packet_follows */
-           crWaitUntil(pktin);                /* Ignore packet */
+           crWaitUntilV(pktin);                /* Ignore packet */
     }
 
     if (ssh->kex->main_type == KEXTYPE_DH) {
@@ -6004,16 +6007,16 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
             ssh2_pkt_adduint32(s->pktout, s->pbits);
             ssh2_pkt_send_noqueue(ssh, s->pktout);
 
-            crWaitUntil(pktin);
+            crWaitUntilV(pktin);
             if (pktin->type != SSH2_MSG_KEX_DH_GEX_GROUP) {
                 bombout(("expected key exchange group packet from server"));
-                crStop(0);
+                crStopV;
             }
             s->p = ssh2_pkt_getmp(pktin);
             s->g = ssh2_pkt_getmp(pktin);
             if (!s->p || !s->g) {
                 bombout(("unable to read mp-ints from incoming group packet"));
-                crStop(0);
+                crStopV;
             }
             ssh->kex_ctx = dh_setup_gex(s->p, s->g);
             s->kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
@@ -6039,10 +6042,10 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
         ssh2_pkt_send_noqueue(ssh, s->pktout);
 
         set_busy_status(ssh->frontend, BUSY_WAITING); /* wait for server */
-        crWaitUntil(pktin);
+        crWaitUntilV(pktin);
         if (pktin->type != s->kex_reply_value) {
             bombout(("expected key exchange reply packet from server"));
-            crStop(0);
+            crStopV;
         }
         set_busy_status(ssh->frontend, BUSY_CPU); /* cogitate */
         ssh_pkt_getstring(pktin, &s->hostkeydata, &s->hostkeylen);
@@ -6050,7 +6053,7 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
         s->f = ssh2_pkt_getmp(pktin);
         if (!s->f) {
             bombout(("unable to parse key exchange reply packet"));
-            crStop(0);
+            crStopV;
         }
         ssh_pkt_getstring(pktin, &s->sigdata, &s->siglen);
 
@@ -6083,10 +6086,10 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
          * RSA key exchange. First expect a KEXRSA_PUBKEY packet
          * from the server.
          */
-        crWaitUntil(pktin);
+        crWaitUntilV(pktin);
         if (pktin->type != SSH2_MSG_KEXRSA_PUBKEY) {
             bombout(("expected RSA public key packet from server"));
-            crStop(0);
+            crStopV;
         }
 
         ssh_pkt_getstring(pktin, &s->hostkeydata, &s->hostkeylen);
@@ -6105,7 +6108,7 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
         if (!s->rsakey) {
             sfree(s->rsakeydata);
             bombout(("unable to parse RSA public key from server"));
-            crStop(0);
+            crStopV;
         }
 
         hash_string(ssh->kex->hash, ssh->exhash, s->rsakeydata, s->rsakeylen);
@@ -6165,11 +6168,11 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
 
         ssh_rsakex_freekey(s->rsakey);
 
-        crWaitUntil(pktin);
+        crWaitUntilV(pktin);
         if (pktin->type != SSH2_MSG_KEXRSA_DONE) {
             sfree(s->rsakeydata);
             bombout(("expected signature packet from server"));
-            crStop(0);
+            crStopV;
         }
 
         ssh_pkt_getstring(pktin, &s->sigdata, &s->siglen);
@@ -6193,7 +6196,7 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
                                 (char *)s->exchange_hash,
                                 ssh->kex->hash->hlen)) {
        bombout(("Server's host key did not match the signature supplied"));
-       crStop(0);
+       crStopV;
     }
 
     /*
@@ -6210,11 +6213,11 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
                                     ssh_dialog_callback, ssh);
     if (s->dlgret < 0) {
         do {
-            crReturn(0);
+            crReturnV;
             if (pktin) {
                 bombout(("Unexpected data from server while waiting"
                          " for user host key response"));
-                    crStop(0);
+                    crStopV;
             }
         } while (pktin || inlen > 0);
         s->dlgret = ssh->user_response;
@@ -6223,7 +6226,7 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
     if (s->dlgret == 0) {
        ssh_disconnect(ssh, "User aborted at host key verification", NULL,
                       0, TRUE);
-        crStop(0);
+        crStopV;
     }
     if (!s->got_session_id) {     /* don't bother logging this in rekeys */
        logevent("Host key fingerprint is:");
@@ -6313,10 +6316,10 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
     /*
      * Expect SSH2_MSG_NEWKEYS from server.
      */
-    crWaitUntil(pktin);
+    crWaitUntilV(pktin);
     if (pktin->type != SSH2_MSG_NEWKEYS) {
        bombout(("expected new-keys packet from server"));
-       crStop(0);
+       crStopV;
     }
     ssh->incoming_data_size = 0;       /* start counting from here */
 
@@ -6418,7 +6421,7 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
             */
            do_ssh2_authconn(ssh, NULL, 0, NULL);
        }
-       crReturn(1);
+       crReturnV;
     }
     if (pktin) {
        logevent("Server initiated key re-exchange");
@@ -6477,7 +6480,7 @@ static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
     }
     goto begin_key_exchange;
 
-    crFinish(1);
+    crFinishV;
 }
 
 /*
@@ -7465,136 +7468,126 @@ static void ssh2_send_ttymode(void *data, char *mode, char *val)
     ssh2_pkt_adduint32(pktout, arg);
 }
 
-static void ssh2_maybe_setup_x11(struct ssh_channel *c, struct Packet *pktin,
-                                void *ctx)
+static void ssh2_setup_x11(struct ssh_channel *c, struct Packet *pktin,
+                           void *ctx)
 {
-    struct ssh2_maybe_setup_x11_state {
+    struct ssh2_setup_x11_state {
        int crLine;
     };
     Ssh ssh = c->ssh;
     struct Packet *pktout;
-    crStateP(ssh2_maybe_setup_x11_state, ctx);
+    crStateP(ssh2_setup_x11_state, ctx);
 
     crBeginState;
 
+    logevent("Requesting X11 forwarding");
+    pktout = ssh2_chanreq_init(ssh->mainchan, "x11-req",
+                               ssh2_setup_x11, s);
+    ssh2_pkt_addbool(pktout, 0);              /* many connections */
+    ssh2_pkt_addstring(pktout, ssh->x11disp->remoteauthprotoname);
     /*
-     * Potentially enable X11 forwarding.
+     * Note that while we blank the X authentication data here, we don't
+     * take any special action to blank the start of an X11 channel,
+     * so using MIT-MAGIC-COOKIE-1 and actually opening an X connection
+     * without having session blanking enabled is likely to leak your
+     * cookie into the log.
      */
-    if (ssh->mainchan && !ssh->ncmode && conf_get_int(ssh->conf, CONF_x11_forward) &&
-       (ssh->x11disp = x11_setup_display(conf_get_str(ssh->conf, CONF_x11_display),
-                                         conf_get_int(ssh->conf, CONF_x11_auth), ssh->conf))) {
-       logevent("Requesting X11 forwarding");
-       pktout = ssh2_chanreq_init(ssh->mainchan, "x11-req",
-                                  ssh2_maybe_setup_x11, s);
-       ssh2_pkt_addbool(pktout, 0);           /* many connections */
-       ssh2_pkt_addstring(pktout, ssh->x11disp->remoteauthprotoname);
-       /*
-        * Note that while we blank the X authentication data here, we don't
-        * take any special action to blank the start of an X11 channel,
-        * so using MIT-MAGIC-COOKIE-1 and actually opening an X connection
-        * without having session blanking enabled is likely to leak your
-        * cookie into the log.
-        */
-       dont_log_password(ssh, pktout, PKTLOG_BLANK);
-       ssh2_pkt_addstring(pktout, ssh->x11disp->remoteauthdatastring);
-       end_log_omission(ssh, pktout);
-       ssh2_pkt_adduint32(pktout, ssh->x11disp->screennum);
-       ssh2_pkt_send(ssh, pktout);
+    dont_log_password(ssh, pktout, PKTLOG_BLANK);
+    ssh2_pkt_addstring(pktout, ssh->x11disp->remoteauthdatastring);
+    end_log_omission(ssh, pktout);
+    ssh2_pkt_adduint32(pktout, ssh->x11disp->screennum);
+    ssh2_pkt_send(ssh, pktout);
 
-       crWaitUntilV(pktin);
+    crWaitUntilV(pktin);
 
-       if (pktin) {
-           if (pktin->type == SSH2_MSG_CHANNEL_SUCCESS) {
-               logevent("X11 forwarding enabled");
-               ssh->X11_fwd_enabled = TRUE;
-           } else
-               logevent("X11 forwarding refused");
-       }
+    if (pktin) {
+        if (pktin->type == SSH2_MSG_CHANNEL_SUCCESS) {
+            logevent("X11 forwarding enabled");
+            ssh->X11_fwd_enabled = TRUE;
+        } else
+            logevent("X11 forwarding refused");
     }
+
     crFinishFreeV;
 }
 
-static void ssh2_maybe_setup_agent(struct ssh_channel *c, struct Packet *pktin,
+static void ssh2_setup_agent(struct ssh_channel *c, struct Packet *pktin,
                                   void *ctx)
 {
-    struct ssh2_maybe_setup_agent_state {
+    struct ssh2_setup_agent_state {
        int crLine;
     };
     Ssh ssh = c->ssh;
     struct Packet *pktout;
-    crStateP(ssh2_maybe_setup_agent_state, ctx);
+    crStateP(ssh2_setup_agent_state, ctx);
 
     crBeginState;
 
-    if (ssh->mainchan && !ssh->ncmode && conf_get_int(ssh->conf, CONF_agentfwd) && agent_exists()) {
-       logevent("Requesting OpenSSH-style agent forwarding");
-       pktout = ssh2_chanreq_init(ssh->mainchan, "auth-agent-req@openssh.com",
-                                  ssh2_maybe_setup_agent, s);
-       ssh2_pkt_send(ssh, pktout);
+    logevent("Requesting OpenSSH-style agent forwarding");
+    pktout = ssh2_chanreq_init(ssh->mainchan, "auth-agent-req@openssh.com",
+                               ssh2_setup_agent, s);
+    ssh2_pkt_send(ssh, pktout);
 
-       crWaitUntilV(pktin);
+    crWaitUntilV(pktin);
 
-       if (pktin) {
-           if (pktin->type == SSH2_MSG_CHANNEL_SUCCESS) {
-               logevent("Agent forwarding enabled");
-               ssh->agentfwd_enabled = TRUE;
-           } else
-               logevent("Agent forwarding refused");
-       }
+    if (pktin) {
+        if (pktin->type == SSH2_MSG_CHANNEL_SUCCESS) {
+            logevent("Agent forwarding enabled");
+            ssh->agentfwd_enabled = TRUE;
+        } else
+            logevent("Agent forwarding refused");
     }
+
     crFinishFreeV;
 }
 
-static void ssh2_maybe_setup_pty(struct ssh_channel *c, struct Packet *pktin,
+static void ssh2_setup_pty(struct ssh_channel *c, struct Packet *pktin,
                                 void *ctx)
 {
-    struct ssh2_maybe_setup_pty_state {
+    struct ssh2_setup_pty_state {
        int crLine;
     };
     Ssh ssh = c->ssh;
     struct Packet *pktout;
-    crStateP(ssh2_maybe_setup_pty_state, ctx);
+    crStateP(ssh2_setup_pty_state, ctx);
 
     crBeginState;
 
-    if (ssh->mainchan && !ssh->ncmode && !conf_get_int(ssh->conf, CONF_nopty)) {
-       /* Unpick the terminal-speed string. */
-       /* XXX perhaps we should allow no speeds to be sent. */
-        ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
-       sscanf(conf_get_str(ssh->conf, CONF_termspeed), "%d,%d", &ssh->ospeed, &ssh->ispeed);
-       /* Build the pty request. */
-       pktout = ssh2_chanreq_init(ssh->mainchan, "pty-req",
-                                  ssh2_maybe_setup_pty, s);
-       ssh2_pkt_addstring(pktout, conf_get_str(ssh->conf, CONF_termtype));
-       ssh2_pkt_adduint32(pktout, ssh->term_width);
-       ssh2_pkt_adduint32(pktout, ssh->term_height);
-       ssh2_pkt_adduint32(pktout, 0);         /* pixel width */
-       ssh2_pkt_adduint32(pktout, 0);         /* pixel height */
-       ssh2_pkt_addstring_start(pktout);
-       parse_ttymodes(ssh, ssh2_send_ttymode, (void *)pktout);
-       ssh2_pkt_addbyte(pktout, SSH2_TTY_OP_ISPEED);
-       ssh2_pkt_adduint32(pktout, ssh->ispeed);
-       ssh2_pkt_addbyte(pktout, SSH2_TTY_OP_OSPEED);
-       ssh2_pkt_adduint32(pktout, ssh->ospeed);
-       ssh2_pkt_addstring_data(pktout, "\0", 1); /* TTY_OP_END */
-       ssh2_pkt_send(ssh, pktout);
-       ssh->state = SSH_STATE_INTERMED;
+    /* Unpick the terminal-speed string. */
+    /* XXX perhaps we should allow no speeds to be sent. */
+    ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
+    sscanf(conf_get_str(ssh->conf, CONF_termspeed), "%d,%d", &ssh->ospeed, &ssh->ispeed);
+    /* Build the pty request. */
+    pktout = ssh2_chanreq_init(ssh->mainchan, "pty-req",
+                               ssh2_setup_pty, s);
+    ssh2_pkt_addstring(pktout, conf_get_str(ssh->conf, CONF_termtype));
+    ssh2_pkt_adduint32(pktout, ssh->term_width);
+    ssh2_pkt_adduint32(pktout, ssh->term_height);
+    ssh2_pkt_adduint32(pktout, 0);            /* pixel width */
+    ssh2_pkt_adduint32(pktout, 0);            /* pixel height */
+    ssh2_pkt_addstring_start(pktout);
+    parse_ttymodes(ssh, ssh2_send_ttymode, (void *)pktout);
+    ssh2_pkt_addbyte(pktout, SSH2_TTY_OP_ISPEED);
+    ssh2_pkt_adduint32(pktout, ssh->ispeed);
+    ssh2_pkt_addbyte(pktout, SSH2_TTY_OP_OSPEED);
+    ssh2_pkt_adduint32(pktout, ssh->ospeed);
+    ssh2_pkt_addstring_data(pktout, "\0", 1); /* TTY_OP_END */
+    ssh2_pkt_send(ssh, pktout);
+    ssh->state = SSH_STATE_INTERMED;
+
+    crWaitUntilV(pktin);
 
-       crWaitUntilV(pktin);
-
-       if (pktin) {
-           if (pktin->type == SSH2_MSG_CHANNEL_SUCCESS) {
-               logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
-                         ssh->ospeed, ssh->ispeed);
-               ssh->got_pty = TRUE;
-           } else {
-               c_write_str(ssh, "Server refused to allocate pty\r\n");
-               ssh->editing = ssh->echoing = 1;
-           }
-       }
-    } else {
-       ssh->editing = ssh->echoing = 1;
+    if (pktin) {
+        if (pktin->type == SSH2_MSG_CHANNEL_SUCCESS) {
+            logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
+                      ssh->ospeed, ssh->ispeed);
+            ssh->got_pty = TRUE;
+        } else {
+            c_write_str(ssh, "Server refused to allocate pty\r\n");
+            ssh->editing = ssh->echoing = 1;
+        }
     }
+
     crFinishFreeV;
 }
 
@@ -7618,7 +7611,7 @@ static void ssh2_setup_env(struct ssh_channel *c, struct Packet *pktin,
      * then wait for a whole bunch of successes or failures.
      */
     s->num_env = 0;
-    if (ssh->mainchan && !ssh->ncmode) {
+    {
        char *key, *val;
 
        for (val = conf_get_str_strs(ssh->conf, CONF_environmt, NULL, &key);
@@ -9241,22 +9234,34 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
     /*
      * Potentially enable X11 forwarding.
      */
-    ssh2_maybe_setup_x11(ssh->mainchan, NULL, NULL);
+    /*
+     * Potentially enable X11 forwarding.
+     */
+    if (ssh->mainchan && !ssh->ncmode && conf_get_int(ssh->conf, CONF_x11_forward) &&
+       (ssh->x11disp = x11_setup_display(conf_get_str(ssh->conf, CONF_x11_display),
+                                         conf_get_int(ssh->conf, CONF_x11_auth), ssh->conf)))
+        ssh2_setup_x11(ssh->mainchan, NULL, NULL);
 
     /*
      * Potentially enable agent forwarding.
      */
-    ssh2_maybe_setup_agent(ssh->mainchan, NULL, NULL);
+    if (ssh->mainchan && !ssh->ncmode && conf_get_int(ssh->conf, CONF_agentfwd) && agent_exists())
+        ssh2_setup_agent(ssh->mainchan, NULL, NULL);
 
     /*
      * Now allocate a pty for the session.
      */
-    ssh2_maybe_setup_pty(ssh->mainchan, NULL, NULL);
+    if (ssh->mainchan && !ssh->ncmode && !conf_get_int(ssh->conf, CONF_nopty)) {
+        ssh2_setup_pty(ssh->mainchan, NULL, NULL);
+    } else {
+       ssh->editing = ssh->echoing = 1;
+    }
 
     /*
      * Send environment variables.
      */
-    ssh2_setup_env(ssh->mainchan, NULL, NULL);
+    if (ssh->mainchan && !ssh->ncmode)
+        ssh2_setup_env(ssh->mainchan, NULL, NULL);
 
     /*
      * Start a shell or a remote command. We may have to attempt