Sebastian Kuschel reports that pfd_closing can be called for a socket
[u/mdw/putty] / telnet.c
index e6ad83e..6a56da7 100644 (file)
--- a/telnet.c
+++ b/telnet.c
@@ -4,6 +4,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <limits.h>
 
 #include "putty.h"
 
 #define SUSP    237                   /* Suspend process */
 #define xEOF    236                   /* End of file: EOF is already used... */
 
-#define TELOPT_BINARY  0              /* 8-bit data path */
-#define TELOPT_ECHO    1              /* echo */
-#define        TELOPT_RCP      2              /* prepare to reconnect */
-#define        TELOPT_SGA      3              /* suppress go ahead */
-#define        TELOPT_NAMS     4              /* approximate message size */
-#define        TELOPT_STATUS   5              /* give status */
-#define        TELOPT_TM       6              /* timing mark */
-#define        TELOPT_RCTE     7              /* remote controlled transmission and echo */
-#define TELOPT_NAOL    8              /* negotiate about output line width */
-#define TELOPT_NAOP    9              /* negotiate about output page size */
-#define TELOPT_NAOCRD  10             /* negotiate about CR disposition */
-#define TELOPT_NAOHTS  11             /* negotiate about horizontal tabstops */
-#define TELOPT_NAOHTD  12             /* negotiate about horizontal tab disposition */
-#define TELOPT_NAOFFD  13             /* negotiate about formfeed disposition */
-#define TELOPT_NAOVTS  14             /* negotiate about vertical tab stops */
-#define TELOPT_NAOVTD  15             /* negotiate about vertical tab disposition */
-#define TELOPT_NAOLFD  16             /* negotiate about output LF disposition */
-#define TELOPT_XASCII  17             /* extended ascic character set */
-#define        TELOPT_LOGOUT   18             /* force logout */
-#define        TELOPT_BM       19             /* byte macro */
-#define        TELOPT_DET      20             /* data entry terminal */
-#define        TELOPT_SUPDUP   21             /* supdup protocol */
-#define        TELOPT_SUPDUPOUTPUT 22         /* supdup output */
-#define        TELOPT_SNDLOC   23             /* send location */
-#define        TELOPT_TTYPE    24             /* terminal type */
-#define        TELOPT_EOR      25             /* end or record */
-#define        TELOPT_TUID     26             /* TACACS user identification */
-#define        TELOPT_OUTMRK   27             /* output marking */
-#define        TELOPT_TTYLOC   28             /* terminal location number */
-#define        TELOPT_3270REGIME 29           /* 3270 regime */
-#define        TELOPT_X3PAD    30             /* X.3 PAD */
-#define        TELOPT_NAWS     31             /* window size */
-#define        TELOPT_TSPEED   32             /* terminal speed */
-#define        TELOPT_LFLOW    33             /* remote flow control */
-#define TELOPT_LINEMODE        34             /* Linemode option */
-#define TELOPT_XDISPLOC        35             /* X Display Location */
-#define TELOPT_OLD_ENVIRON 36         /* Old - Environment variables */
-#define        TELOPT_AUTHENTICATION 37       /* Authenticate */
-#define        TELOPT_ENCRYPT  38             /* Encryption option */
-#define TELOPT_NEW_ENVIRON 39         /* New - Environment variables */
-#define TELOPT_TN3270E 40             /* TN3270 enhancements */
-#define TELOPT_XAUTH   41
-#define TELOPT_CHARSET 42             /* Character set */
-#define TELOPT_RSP     43             /* Remote serial port */
-#define TELOPT_COM_PORT_OPTION 44      /* Com port control */
-#define TELOPT_SLE     45             /* Suppress local echo */
-#define TELOPT_STARTTLS        46             /* Start TLS */
-#define TELOPT_KERMIT  47             /* Automatic Kermit file transfer */
-#define TELOPT_SEND_URL        48
-#define TELOPT_FORWARD_X 49
-#define TELOPT_PRAGMA_LOGON    138
-#define TELOPT_SSPI_LOGON      139
-#define TELOPT_PRAGMA_HEARTBEAT        140
-#define        TELOPT_EXOPL    255            /* extended-options-list */
+#define TELOPTS(X) \
+    X(BINARY, 0)                       /* 8-bit data path */ \
+    X(ECHO, 1)                         /* echo */ \
+    X(RCP, 2)                          /* prepare to reconnect */ \
+    X(SGA, 3)                          /* suppress go ahead */ \
+    X(NAMS, 4)                         /* approximate message size */ \
+    X(STATUS, 5)                       /* give status */ \
+    X(TM, 6)                           /* timing mark */ \
+    X(RCTE, 7)                         /* remote controlled transmission and echo */ \
+    X(NAOL, 8)                         /* negotiate about output line width */ \
+    X(NAOP, 9)                         /* negotiate about output page size */ \
+    X(NAOCRD, 10)                      /* negotiate about CR disposition */ \
+    X(NAOHTS, 11)                      /* negotiate about horizontal tabstops */ \
+    X(NAOHTD, 12)                      /* negotiate about horizontal tab disposition */ \
+    X(NAOFFD, 13)                      /* negotiate about formfeed disposition */ \
+    X(NAOVTS, 14)                      /* negotiate about vertical tab stops */ \
+    X(NAOVTD, 15)                      /* negotiate about vertical tab disposition */ \
+    X(NAOLFD, 16)                      /* negotiate about output LF disposition */ \
+    X(XASCII, 17)                      /* extended ascic character set */ \
+    X(LOGOUT, 18)                      /* force logout */ \
+    X(BM, 19)                          /* byte macro */ \
+    X(DET, 20)                         /* data entry terminal */ \
+    X(SUPDUP, 21)                      /* supdup protocol */ \
+    X(SUPDUPOUTPUT, 22)                /* supdup output */ \
+    X(SNDLOC, 23)                      /* send location */ \
+    X(TTYPE, 24)                       /* terminal type */ \
+    X(EOR, 25)                         /* end or record */ \
+    X(TUID, 26)                        /* TACACS user identification */ \
+    X(OUTMRK, 27)                      /* output marking */ \
+    X(TTYLOC, 28)                      /* terminal location number */ \
+    X(3270REGIME, 29)                  /* 3270 regime */ \
+    X(X3PAD, 30)                       /* X.3 PAD */ \
+    X(NAWS, 31)                        /* window size */ \
+    X(TSPEED, 32)                      /* terminal speed */ \
+    X(LFLOW, 33)                       /* remote flow control */ \
+    X(LINEMODE, 34)                    /* Linemode option */ \
+    X(XDISPLOC, 35)                    /* X Display Location */ \
+    X(OLD_ENVIRON, 36)                 /* Old - Environment variables */ \
+    X(AUTHENTICATION, 37)              /* Authenticate */ \
+    X(ENCRYPT, 38)                     /* Encryption option */ \
+    X(NEW_ENVIRON, 39)                 /* New - Environment variables */ \
+    X(TN3270E, 40)                     /* TN3270 enhancements */ \
+    X(XAUTH, 41)                       \
+    X(CHARSET, 42)                     /* Character set */ \
+    X(RSP, 43)                         /* Remote serial port */ \
+    X(COM_PORT_OPTION, 44)             /* Com port control */ \
+    X(SLE, 45)                         /* Suppress local echo */ \
+    X(STARTTLS, 46)                    /* Start TLS */ \
+    X(KERMIT, 47)                      /* Automatic Kermit file transfer */ \
+    X(SEND_URL, 48)                    \
+    X(FORWARD_X, 49)                   \
+    X(PRAGMA_LOGON, 138)               \
+    X(SSPI_LOGON, 139)                 \
+    X(PRAGMA_HEARTBEAT, 140)           \
+    X(EXOPL, 255)                      /* extended-options-list */
+
+#define telnet_enum(x,y) TELOPT_##x = y,
+enum { TELOPTS(telnet_enum) dummy=0 };
+#undef telnet_enum
 
 #define        TELQUAL_IS      0              /* option is... */
 #define        TELQUAL_SEND    1              /* send option */
 
 static char *telopt(int opt)
 {
-#define i(x) if (opt == TELOPT_ ## x) return #x;
-    i(BINARY);
-    i(ECHO);
-    i(RCP);
-    i(SGA);
-    i(NAMS);
-    i(STATUS);
-    i(TM);
-    i(RCTE);
-    i(NAOL);
-    i(NAOP);
-    i(NAOCRD);
-    i(NAOHTS);
-    i(NAOHTD);
-    i(NAOFFD);
-    i(NAOVTS);
-    i(NAOVTD);
-    i(NAOLFD);
-    i(XASCII);
-    i(LOGOUT);
-    i(BM);
-    i(DET);
-    i(SUPDUP);
-    i(SUPDUPOUTPUT);
-    i(SNDLOC);
-    i(TTYPE);
-    i(EOR);
-    i(TUID);
-    i(OUTMRK);
-    i(TTYLOC);
-    i(X3PAD);
-    i(NAWS);
-    i(TSPEED);
-    i(LFLOW);
-    i(LINEMODE);
-    i(XDISPLOC);
-    i(OLD_ENVIRON);
-    i(AUTHENTICATION);
-    i(ENCRYPT);
-    i(NEW_ENVIRON);
-    i(TN3270E);
-    i(XAUTH);
-    i(CHARSET);
-    i(RSP);
-    i(COM_PORT_OPTION);
-    i(SLE);
-    i(STARTTLS);
-    i(KERMIT);
-    i(SEND_URL);
-    i(FORWARD_X);
-    i(PRAGMA_LOGON);
-    i(SSPI_LOGON);
-    i(PRAGMA_HEARTBEAT);
-    i(EXOPL);
-#undef i
-    return "<unknown>";
+#define telnet_str(x,y) case TELOPT_##x: return #x;
+    switch (opt) {
+       TELOPTS(telnet_str)
+      default:
+       return "<unknown>";
+    }
+#undef telnet_str
 }
 
 static void telnet_size(void *handle, int width, int height);
@@ -225,6 +182,7 @@ typedef struct telnet_tag {
     /* the above field _must_ be first in the structure */
 
     Socket s;
+    int closed_on_socket_error;
 
     void *frontend;
     void *ldisc;
@@ -245,7 +203,7 @@ typedef struct telnet_tag {
            SEENSB, SUBNEGOT, SUBNEG_IAC, SEENCR
     } state;
 
-    Config cfg;
+    Conf *conf;
 
     Pinger pinger;
 } *Telnet;
@@ -407,42 +365,46 @@ static void proc_rec_opt(Telnet telnet, int cmd, int option)
 
 static void process_subneg(Telnet telnet)
 {
-    unsigned char b[2048], *p, *q;
-    int var, value, n;
-    char *e;
+    unsigned char *b, *p, *q;
+    int var, value, n, bsize;
+    char *e, *eval, *ekey, *user;
 
     switch (telnet->sb_opt) {
       case TELOPT_TSPEED:
        if (telnet->sb_len == 1 && telnet->sb_buf[0] == TELQUAL_SEND) {
            char *logbuf;
+           char *termspeed = conf_get_str(telnet->conf, CONF_termspeed);
+           b = snewn(20 + strlen(termspeed), unsigned char);
            b[0] = IAC;
            b[1] = SB;
            b[2] = TELOPT_TSPEED;
            b[3] = TELQUAL_IS;
-           strcpy((char *)(b + 4), telnet->cfg.termspeed);
-           n = 4 + strlen(telnet->cfg.termspeed);
+           strcpy((char *)(b + 4), termspeed);
+           n = 4 + strlen(termspeed);
            b[n] = IAC;
            b[n + 1] = SE;
            telnet->bufsize = sk_write(telnet->s, (char *)b, n + 2);
            logevent(telnet->frontend, "server:\tSB TSPEED SEND");
-           logbuf = dupprintf("client:\tSB TSPEED IS %s", telnet->cfg.termspeed);
+           logbuf = dupprintf("client:\tSB TSPEED IS %s", termspeed);
            logevent(telnet->frontend, logbuf);
            sfree(logbuf);
+           sfree(b);
        } else
            logevent(telnet->frontend, "server:\tSB TSPEED <something weird>");
        break;
       case TELOPT_TTYPE:
        if (telnet->sb_len == 1 && telnet->sb_buf[0] == TELQUAL_SEND) {
            char *logbuf;
+           char *termtype = conf_get_str(telnet->conf, CONF_termtype);
+           b = snewn(20 + strlen(termtype), unsigned char);
            b[0] = IAC;
            b[1] = SB;
            b[2] = TELOPT_TTYPE;
            b[3] = TELQUAL_IS;
-           for (n = 0; telnet->cfg.termtype[n]; n++)
-               b[n + 4] = (telnet->cfg.termtype[n] >= 'a'
-                           && telnet->cfg.termtype[n] <=
-                           'z' ? telnet->cfg.termtype[n] + 'A' -
-                           'a' : telnet->cfg.termtype[n]);
+           for (n = 0; termtype[n]; n++)
+               b[n + 4] = (termtype[n] >= 'a' && termtype[n] <= 'z' ?
+                           termtype[n] + 'A' - 'a' :
+                           termtype[n]);
            b[n + 4] = IAC;
            b[n + 5] = SE;
            telnet->bufsize = sk_write(telnet->s, (char *)b, n + 6);
@@ -451,6 +413,7 @@ static void process_subneg(Telnet telnet)
            logbuf = dupprintf("client:\tSB TTYPE IS %s", b + 4);
            logevent(telnet->frontend, logbuf);
            sfree(logbuf);
+           sfree(b);
        } else
            logevent(telnet->frontend, "server:\tSB TTYPE <something weird>\r\n");
        break;
@@ -465,7 +428,7 @@ static void process_subneg(Telnet telnet)
            logevent(telnet->frontend, logbuf);
            sfree(logbuf);
            if (telnet->sb_opt == TELOPT_OLD_ENVIRON) {
-               if (telnet->cfg.rfc_environ) {
+               if (conf_get_int(telnet->conf, CONF_rfc_environ)) {
                    value = RFC_VALUE;
                    var = RFC_VAR;
                } else {
@@ -493,46 +456,75 @@ static void process_subneg(Telnet telnet)
                value = RFC_VALUE;
                var = RFC_VAR;
            }
+           bsize = 20;
+           for (eval = conf_get_str_strs(telnet->conf, CONF_environmt,
+                                        NULL, &ekey);
+                eval != NULL;
+                eval = conf_get_str_strs(telnet->conf, CONF_environmt,
+                                        ekey, &ekey))
+                bsize += strlen(ekey) + strlen(eval) + 2;
+           user = get_remote_username(telnet->conf);
+           if (user)
+               bsize += 6 + strlen(user);
+
+           b = snewn(bsize, unsigned char);
            b[0] = IAC;
            b[1] = SB;
            b[2] = telnet->sb_opt;
            b[3] = TELQUAL_IS;
            n = 4;
-           e = telnet->cfg.environmt;
-           while (*e) {
+           for (eval = conf_get_str_strs(telnet->conf, CONF_environmt,
+                                        NULL, &ekey);
+                eval != NULL;
+                eval = conf_get_str_strs(telnet->conf, CONF_environmt,
+                                        ekey, &ekey)) {
                b[n++] = var;
-               while (*e && *e != '\t')
-                   b[n++] = *e++;
-               if (*e == '\t')
-                   e++;
+               for (e = ekey; *e; e++)
+                   b[n++] = *e;
                b[n++] = value;
-               while (*e)
-                   b[n++] = *e++;
-               e++;
+               for (e = eval; *e; e++)
+                   b[n++] = *e;
            }
-           if (*telnet->cfg.username) {
+           if (user) {
                b[n++] = var;
                b[n++] = 'U';
                b[n++] = 'S';
                b[n++] = 'E';
                b[n++] = 'R';
                b[n++] = value;
-               e = telnet->cfg.username;
-               while (*e)
-                   b[n++] = *e++;
+               for (e = user; *e; e++)
+                   b[n++] = *e;
            }
            b[n++] = IAC;
            b[n++] = SE;
            telnet->bufsize = sk_write(telnet->s, (char *)b, n);
-           logbuf = dupprintf("client:\tSB %s IS %s%s%s%s",
-                              telopt(telnet->sb_opt),
-                              *telnet->cfg.username ? "USER=" : "",
-                              telnet->cfg.username,
-                              *telnet->cfg.username ? " " : "",
-                              n == 6 ? "<nothing>" :
-                              (*telnet->cfg.environmt ? "<stuff>" : ""));
-           logevent(telnet->frontend, logbuf);
-           sfree(logbuf);
+           if (n == 6) {
+               logbuf = dupprintf("client:\tSB %s IS <nothing>",
+                                  telopt(telnet->sb_opt));
+               logevent(telnet->frontend, logbuf);
+               sfree(logbuf);
+           } else {
+               logbuf = dupprintf("client:\tSB %s IS:",
+                                  telopt(telnet->sb_opt));
+               logevent(telnet->frontend, logbuf);
+               sfree(logbuf);
+               for (eval = conf_get_str_strs(telnet->conf, CONF_environmt,
+                                            NULL, &ekey);
+                    eval != NULL;
+                    eval = conf_get_str_strs(telnet->conf, CONF_environmt,
+                                            ekey, &ekey)) {
+                   logbuf = dupprintf("\t%s=%s", ekey, eval);
+                   logevent(telnet->frontend, logbuf);
+                   sfree(logbuf);
+               }
+               if (user) {
+                   logbuf = dupprintf("\tUSER=%s", user);
+                   logevent(telnet->frontend, logbuf);
+                   sfree(logbuf);
+               }
+           }
+           sfree(b);
+           sfree(user);
        }
        break;
     }
@@ -670,6 +662,7 @@ static void telnet_log(Plug plug, int type, SockAddr addr, int port,
        msg = dupprintf("Failed to connect to %s: %s", addrbuf, error_msg);
 
     logevent(telnet->frontend, msg);
+    sfree(msg);
 }
 
 static int telnet_closing(Plug plug, const char *error_msg, int error_code,
@@ -677,9 +670,17 @@ static int telnet_closing(Plug plug, const char *error_msg, int error_code,
 {
     Telnet telnet = (Telnet) plug;
 
+    /*
+     * We don't implement independent EOF in each direction for Telnet
+     * connections; as soon as we get word that the remote side has
+     * sent us EOF, we wind up the whole connection.
+     */
+
     if (telnet->s) {
         sk_close(telnet->s);
         telnet->s = NULL;
+        if (error_msg)
+            telnet->closed_on_socket_error = TRUE;
        notify_remote_exit(telnet->frontend);
     }
     if (error_msg) {
@@ -714,9 +715,8 @@ static void telnet_sent(Plug plug, int bufsize)
  * freed by the caller.
  */
 static const char *telnet_init(void *frontend_handle, void **backend_handle,
-                              Config *cfg,
-                              char *host, int port, char **realhost,
-                              int nodelay, int keepalive)
+                              Conf *conf, char *host, int port,
+                              char **realhost, int nodelay, int keepalive)
 {
     static const struct plug_function_table fn_table = {
        telnet_log,
@@ -727,19 +727,22 @@ static const char *telnet_init(void *frontend_handle, void **backend_handle,
     SockAddr addr;
     const char *err;
     Telnet telnet;
+    char *loghost;
+    int addressfamily;
 
     telnet = snew(struct telnet_tag);
     telnet->fn = &fn_table;
-    telnet->cfg = *cfg;                       /* STRUCTURE COPY */
+    telnet->conf = conf_copy(conf);
     telnet->s = NULL;
+    telnet->closed_on_socket_error = FALSE;
     telnet->echoing = TRUE;
     telnet->editing = TRUE;
     telnet->activated = FALSE;
     telnet->sb_buf = NULL;
     telnet->sb_size = 0;
     telnet->frontend = frontend_handle;
-    telnet->term_width = telnet->cfg.width;
-    telnet->term_height = telnet->cfg.height;
+    telnet->term_width = conf_get_int(telnet->conf, CONF_width);
+    telnet->term_height = conf_get_int(telnet->conf, CONF_height);
     telnet->state = TOP_LEVEL;
     telnet->ldisc = NULL;
     telnet->pinger = NULL;
@@ -750,14 +753,15 @@ static const char *telnet_init(void *frontend_handle, void **backend_handle,
      */
     {
        char *buf;
+       addressfamily = conf_get_int(telnet->conf, CONF_addressfamily);
        buf = dupprintf("Looking up host \"%s\"%s", host,
-                       (cfg->addressfamily == ADDRTYPE_IPV4 ? " (IPv4)" :
-                        (cfg->addressfamily == ADDRTYPE_IPV6 ? " (IPv6)" :
+                       (addressfamily == ADDRTYPE_IPV4 ? " (IPv4)" :
+                        (addressfamily == ADDRTYPE_IPV6 ? " (IPv6)" :
                          "")));
        logevent(telnet->frontend, buf);
        sfree(buf);
     }
-    addr = name_lookup(host, port, realhost, &telnet->cfg, cfg->addressfamily);
+    addr = name_lookup(host, port, realhost, telnet->conf, addressfamily);
     if ((err = sk_addr_error(addr)) != NULL) {
        sk_addr_free(addr);
        return err;
@@ -770,16 +774,16 @@ static const char *telnet_init(void *frontend_handle, void **backend_handle,
      * Open socket.
      */
     telnet->s = new_connection(addr, *realhost, port, 0, 1,
-                              nodelay, keepalive, (Plug) telnet, &telnet->cfg);
+                              nodelay, keepalive, (Plug) telnet, telnet->conf);
     if ((err = sk_socket_error(telnet->s)) != NULL)
        return err;
 
-    telnet->pinger = pinger_new(&telnet->cfg, &telnet_backend, telnet);
+    telnet->pinger = pinger_new(telnet->conf, &telnet_backend, telnet);
 
     /*
      * Initialise option states.
      */
-    if (telnet->cfg.passive_telnet) {
+    if (conf_get_int(telnet->conf, CONF_passive_telnet)) {
        const struct Opt *const *o;
 
        for (o = opts; *o; o++)
@@ -805,6 +809,26 @@ static const char *telnet_init(void *frontend_handle, void **backend_handle,
      */
     update_specials_menu(telnet->frontend);
 
+    /*
+     * loghost overrides realhost, if specified.
+     */
+    loghost = conf_get_str(telnet->conf, CONF_loghost);
+    if (*loghost) {
+       char *colon;
+
+       sfree(*realhost);
+       *realhost = dupstr(loghost);
+       colon = strrchr(*realhost, ':');
+       if (colon) {
+           /*
+            * FIXME: if we ever update this aspect of ssh.c for
+            * IPv6 literal management, this should change in line
+            * with it.
+            */
+           *colon++ = '\0';
+       }
+    }
+
     return NULL;
 }
 
@@ -817,6 +841,7 @@ static void telnet_free(void *handle)
        sk_close(telnet->s);
     if (telnet->pinger)
        pinger_free(telnet->pinger);
+    conf_free(telnet->conf);
     sfree(telnet);
 }
 /*
@@ -824,11 +849,12 @@ static void telnet_free(void *handle)
  * necessary, in this backend: we just save the fresh config for
  * any subsequent negotiations.
  */
-static void telnet_reconfig(void *handle, Config *cfg)
+static void telnet_reconfig(void *handle, Conf *conf)
 {
     Telnet telnet = (Telnet) handle;
-    pinger_reconfig(telnet->pinger, &telnet->cfg, cfg);
-    telnet->cfg = *cfg;                       /* STRUCTURE COPY */
+    pinger_reconfig(telnet->pinger, telnet->conf, conf);
+    conf_free(telnet->conf);
+    telnet->conf = conf_copy(conf);
 }
 
 /*
@@ -1076,6 +1102,8 @@ static int telnet_exitcode(void *handle)
     Telnet telnet = (Telnet) handle;
     if (telnet->s != NULL)
         return -1;                     /* still connected */
+    else if (telnet->closed_on_socket_error)
+        return INT_MAX;     /* a socket error counts as an unclean exit */
     else
         /* Telnet doesn't transmit exit codes back to the client */
         return 0;
@@ -1106,5 +1134,7 @@ Backend telnet_backend = {
     telnet_provide_logctx,
     telnet_unthrottle,
     telnet_cfg_info,
+    "telnet",
+    PROT_TELNET,
     23
 };