X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/39934deb5202149f98198c111a35c21cb4d0d0f8..881da16842e210236b12a040a19bf480de3a5a92:/telnet.c diff --git a/telnet.c b/telnet.c index 8b2c4289..ed685f10 100644 --- a/telnet.c +++ b/telnet.c @@ -1,3 +1,7 @@ +/* + * Telnet backend. + */ + #include #include @@ -196,12 +200,10 @@ static const struct Opt o_tspeed = { WILL, WONT, DO, DONT, TELOPT_TSPEED, OPTINDEX_TSPEED, REQUESTED }; static const struct Opt o_ttype = { WILL, WONT, DO, DONT, TELOPT_TTYPE, OPTINDEX_TTYPE, REQUESTED }; -static const struct Opt o_oenv = { WILL, WONT, DO, DONT, TELOPT_OLD_ENVIRON, - OPTINDEX_OENV, INACTIVE -}; -static const struct Opt o_nenv = { WILL, WONT, DO, DONT, TELOPT_NEW_ENVIRON, - OPTINDEX_NENV, REQUESTED -}; +static const struct Opt o_oenv = + { WILL, WONT, DO, DONT, TELOPT_OLD_ENVIRON, OPTINDEX_OENV, INACTIVE }; +static const struct Opt o_nenv = + { WILL, WONT, DO, DONT, TELOPT_NEW_ENVIRON, OPTINDEX_NENV, REQUESTED }; static const struct Opt o_echo = { DO, DONT, WILL, WONT, TELOPT_ECHO, OPTINDEX_ECHO, REQUESTED }; static const struct Opt o_we_sga = @@ -252,11 +254,10 @@ typedef struct telnet_tag { #define SB_DELTA 1024 -static void c_write1(Telnet telnet, int c) +static void c_write(Telnet telnet, char *buf, int len) { int backlog; - char cc = (char) c; - backlog = from_backend(telnet->frontend, 0, &cc, 1); + backlog = from_backend(telnet->frontend, 0, buf, len); sk_set_frozen(telnet->s, backlog > TELNET_MAX_BACKLOG); } @@ -396,9 +397,12 @@ static void proc_rec_opt(Telnet telnet, int cmd, int option) } /* * If we reach here, the option was one we weren't prepared to - * cope with. So send a negative ack. + * cope with. If the request was positive (WILL or DO), we send + * a negative ack to indicate refusal. If the request was + * negative (WONT / DONT), we must do nothing. */ - send_opt(telnet, (cmd == WILL ? DONT : WONT), option); + if (cmd == WILL || cmd == DO) + send_opt(telnet, (cmd == WILL ? DONT : WONT), option); } static void process_subneg(Telnet telnet) @@ -536,6 +540,16 @@ static void process_subneg(Telnet telnet) static void do_telnet_read(Telnet telnet, char *buf, int len) { + char *outbuf = NULL; + int outbuflen = 0, outbufsize = 0; + +#define ADDTOBUF(c) do { \ + if (outbuflen >= outbufsize) { \ + outbufsize = outbuflen + 256; \ + outbuf = sresize(outbuf, outbufsize, char); \ + } \ + outbuf[outbuflen++] = (c); \ +} while (0) while (len--) { int c = (unsigned char) *buf++; @@ -549,7 +563,7 @@ static void do_telnet_read(Telnet telnet, char *buf, int len) telnet->state = SEENIAC; else { if (!telnet->in_synch) - c_write1(telnet, c); + ADDTOBUF(c); #if 1 /* I can't get the F***ing winsock to insert the urgent IAC @@ -586,7 +600,7 @@ static void do_telnet_read(Telnet telnet, char *buf, int len) } else { /* ignore everything else; print it if it's IAC */ if (c == IAC) { - c_write1(telnet, c); + ADDTOBUF(c); } telnet->state = TOP_LEVEL; } @@ -636,6 +650,26 @@ static void do_telnet_read(Telnet telnet, char *buf, int len) break; } } + + if (outbuflen) + c_write(telnet, outbuf, outbuflen); + sfree(outbuf); +} + +static void telnet_log(Plug plug, int type, SockAddr addr, int port, + const char *error_msg, int error_code) +{ + Telnet telnet = (Telnet) plug; + char addrbuf[256], *msg; + + sk_getaddr(addr, addrbuf, lenof(addrbuf)); + + if (type == 0) + msg = dupprintf("Connecting to %s port %d", addrbuf, port); + else + msg = dupprintf("Failed to connect to %s: %s", addrbuf, error_msg); + + logevent(telnet->frontend, msg); } static int telnet_closing(Plug plug, const char *error_msg, int error_code, @@ -649,10 +683,10 @@ static int telnet_closing(Plug plug, const char *error_msg, int error_code, notify_remote_exit(telnet->frontend); } if (error_msg) { - /* A socket error has occurred. */ logevent(telnet->frontend, error_msg); connection_fatal(telnet->frontend, "%s", error_msg); - } /* Otherwise, the remote side closed the connection normally. */ + } + /* Otherwise, the remote side closed the connection normally. */ return 0; } @@ -685,6 +719,7 @@ static const char *telnet_init(void *frontend_handle, void **backend_handle, int nodelay, int keepalive) { static const struct plug_function_table fn_table = { + telnet_log, telnet_closing, telnet_receive, telnet_sent @@ -715,11 +750,14 @@ static const char *telnet_init(void *frontend_handle, void **backend_handle, */ { char *buf; - buf = dupprintf("Looking up host \"%s\"", host); + buf = dupprintf("Looking up host \"%s\"%s", host, + (cfg->addressfamily == ADDRTYPE_IPV4 ? " (IPv4)" : + (cfg->addressfamily == ADDRTYPE_IPV6 ? " (IPv6)" : + ""))); logevent(telnet->frontend, buf); sfree(buf); } - addr = name_lookup(host, port, realhost, &telnet->cfg); + addr = name_lookup(host, port, realhost, &telnet->cfg, cfg->addressfamily); if ((err = sk_addr_error(addr)) != NULL) { sk_addr_free(addr); return err; @@ -731,13 +769,6 @@ static const char *telnet_init(void *frontend_handle, void **backend_handle, /* * Open socket. */ - { - char *buf, addrbuf[100]; - sk_getaddr(addr, addrbuf, 100); - buf = dupprintf("Connecting to %s port %d", addrbuf, port); - logevent(telnet->frontend, buf); - sfree(buf); - } telnet->s = new_connection(addr, *realhost, port, 0, 1, nodelay, keepalive, (Plug) telnet, &telnet->cfg); if ((err = sk_socket_error(telnet->s)) != NULL) @@ -774,6 +805,25 @@ static const char *telnet_init(void *frontend_handle, void **backend_handle, */ update_specials_menu(telnet->frontend); + /* + * loghost overrides realhost, if specified. + */ + if (*telnet->cfg.loghost) { + char *colon; + + sfree(*realhost); + *realhost = dupstr(telnet->cfg.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; } @@ -1001,10 +1051,10 @@ static const struct telnet_special *telnet_get_specials(void *handle) return specials; } -static Socket telnet_socket(void *handle) +static int telnet_connected(void *handle) { Telnet telnet = (Telnet) handle; - return telnet->s; + return telnet->s != NULL; } static int telnet_sendok(void *handle) @@ -1050,6 +1100,14 @@ static int telnet_exitcode(void *handle) return 0; } +/* + * cfg_info for Telnet does nothing at all. + */ +static int telnet_cfg_info(void *handle) +{ + return 0; +} + Backend telnet_backend = { telnet_init, telnet_free, @@ -1059,12 +1117,15 @@ Backend telnet_backend = { telnet_size, telnet_special, telnet_get_specials, - telnet_socket, + telnet_connected, telnet_exitcode, telnet_sendok, telnet_ldisc, telnet_provide_ldisc, telnet_provide_logctx, telnet_unthrottle, + telnet_cfg_info, + "telnet", + PROT_TELNET, 23 };