From e7e9a66629ada359ad6a35cdb12e0e35b49e889c Mon Sep 17 00:00:00 2001 From: marha Date: Fri, 7 Aug 2009 12:33:59 +0000 Subject: Added plink tool (version without console, except if output is generated) Added possibility to build console application or windows application in makefile.after --- tools/plink/telnet.c | 1091 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1091 insertions(+) create mode 100644 tools/plink/telnet.c (limited to 'tools/plink/telnet.c') diff --git a/tools/plink/telnet.c b/tools/plink/telnet.c new file mode 100644 index 000000000..8fbe88679 --- /dev/null +++ b/tools/plink/telnet.c @@ -0,0 +1,1091 @@ +/* + * Telnet backend. + */ + +#include +#include + +#include "putty.h" + +#ifndef FALSE +#define FALSE 0 +#endif +#ifndef TRUE +#define TRUE 1 +#endif + +#define IAC 255 /* interpret as command: */ +#define DONT 254 /* you are not to use option */ +#define DO 253 /* please, you use option */ +#define WONT 252 /* I won't use option */ +#define WILL 251 /* I will use option */ +#define SB 250 /* interpret as subnegotiation */ +#define SE 240 /* end sub negotiation */ + +#define GA 249 /* you may reverse the line */ +#define EL 248 /* erase the current line */ +#define EC 247 /* erase the current character */ +#define AYT 246 /* are you there */ +#define AO 245 /* abort output--but let prog finish */ +#define IP 244 /* interrupt process--permanently */ +#define BREAK 243 /* break */ +#define DM 242 /* data mark--for connect. cleaning */ +#define NOP 241 /* nop */ +#define EOR 239 /* end of record (transparent mode) */ +#define ABORT 238 /* Abort process */ +#define SUSP 237 /* Suspend process */ +#define xEOF 236 /* End of file: EOF is already used... */ + +#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 */ +#define TELQUAL_INFO 2 /* ENVIRON: informational version of IS */ +#define BSD_VAR 1 +#define BSD_VALUE 0 +#define RFC_VAR 0 +#define RFC_VALUE 1 + +#define CR 13 +#define LF 10 +#define NUL 0 + +#define iswritable(x) \ + ( (x) != IAC && \ + (telnet->opt_states[o_we_bin.index] == ACTIVE || (x) != CR)) + +static char *telopt(int opt) +{ +#define telnet_str(x,y) case TELOPT_##x: return #x; + switch (opt) { + TELOPTS(telnet_str) + default: + return ""; + } +#undef telnet_str +} + +static void telnet_size(void *handle, int width, int height); + +struct Opt { + int send; /* what we initially send */ + int nsend; /* -ve send if requested to stop it */ + int ack, nak; /* +ve and -ve acknowledgements */ + int option; /* the option code */ + int index; /* index into telnet->opt_states[] */ + enum { + REQUESTED, ACTIVE, INACTIVE, REALLY_INACTIVE + } initial_state; +}; + +enum { + OPTINDEX_NAWS, + OPTINDEX_TSPEED, + OPTINDEX_TTYPE, + OPTINDEX_OENV, + OPTINDEX_NENV, + OPTINDEX_ECHO, + OPTINDEX_WE_SGA, + OPTINDEX_THEY_SGA, + OPTINDEX_WE_BIN, + OPTINDEX_THEY_BIN, + NUM_OPTS +}; + +static const struct Opt o_naws = + { WILL, WONT, DO, DONT, TELOPT_NAWS, OPTINDEX_NAWS, REQUESTED }; +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_echo = + { DO, DONT, WILL, WONT, TELOPT_ECHO, OPTINDEX_ECHO, REQUESTED }; +static const struct Opt o_we_sga = + { WILL, WONT, DO, DONT, TELOPT_SGA, OPTINDEX_WE_SGA, REQUESTED }; +static const struct Opt o_they_sga = + { DO, DONT, WILL, WONT, TELOPT_SGA, OPTINDEX_THEY_SGA, REQUESTED }; +static const struct Opt o_we_bin = + { WILL, WONT, DO, DONT, TELOPT_BINARY, OPTINDEX_WE_BIN, INACTIVE }; +static const struct Opt o_they_bin = + { DO, DONT, WILL, WONT, TELOPT_BINARY, OPTINDEX_THEY_BIN, INACTIVE }; + +static const struct Opt *const opts[] = { + &o_naws, &o_tspeed, &o_ttype, &o_oenv, &o_nenv, &o_echo, + &o_we_sga, &o_they_sga, &o_we_bin, &o_they_bin, NULL +}; + +typedef struct telnet_tag { + const struct plug_function_table *fn; + /* the above field _must_ be first in the structure */ + + Socket s; + + void *frontend; + void *ldisc; + int term_width, term_height; + + int opt_states[NUM_OPTS]; + + int echoing, editing; + int activated; + int bufsize; + int in_synch; + int sb_opt, sb_len; + unsigned char *sb_buf; + int sb_size; + + enum { + TOP_LEVEL, SEENIAC, SEENWILL, SEENWONT, SEENDO, SEENDONT, + SEENSB, SUBNEGOT, SUBNEG_IAC, SEENCR + } state; + + Config cfg; + + Pinger pinger; +} *Telnet; + +#define TELNET_MAX_BACKLOG 4096 + +#define SB_DELTA 1024 + +static void c_write(Telnet telnet, char *buf, int len) +{ + int backlog; + backlog = from_backend(telnet->frontend, 0, buf, len); + sk_set_frozen(telnet->s, backlog > TELNET_MAX_BACKLOG); +} + +static void log_option(Telnet telnet, char *sender, int cmd, int option) +{ + char *buf; + /* + * The strange-looking "" below is there to avoid a + * trigraph - a double question mark followed by > maps to a + * closing brace character! + */ + buf = dupprintf("%s:\t%s %s", sender, + (cmd == WILL ? "WILL" : cmd == WONT ? "WONT" : + cmd == DO ? "DO" : cmd == DONT ? "DONT" : ""), + telopt(option)); + logevent(telnet->frontend, buf); + sfree(buf); +} + +static void send_opt(Telnet telnet, int cmd, int option) +{ + unsigned char b[3]; + + b[0] = IAC; + b[1] = cmd; + b[2] = option; + telnet->bufsize = sk_write(telnet->s, (char *)b, 3); + log_option(telnet, "client", cmd, option); +} + +static void deactivate_option(Telnet telnet, const struct Opt *o) +{ + if (telnet->opt_states[o->index] == REQUESTED || + telnet->opt_states[o->index] == ACTIVE) + send_opt(telnet, o->nsend, o->option); + telnet->opt_states[o->index] = REALLY_INACTIVE; +} + +/* + * Generate side effects of enabling or disabling an option. + */ +static void option_side_effects(Telnet telnet, const struct Opt *o, int enabled) +{ + if (o->option == TELOPT_ECHO && o->send == DO) + telnet->echoing = !enabled; + else if (o->option == TELOPT_SGA && o->send == DO) + telnet->editing = !enabled; + if (telnet->ldisc) /* cause ldisc to notice the change */ + ldisc_send(telnet->ldisc, NULL, 0, 0); + + /* Ensure we get the minimum options */ + if (!telnet->activated) { + if (telnet->opt_states[o_echo.index] == INACTIVE) { + telnet->opt_states[o_echo.index] = REQUESTED; + send_opt(telnet, o_echo.send, o_echo.option); + } + if (telnet->opt_states[o_we_sga.index] == INACTIVE) { + telnet->opt_states[o_we_sga.index] = REQUESTED; + send_opt(telnet, o_we_sga.send, o_we_sga.option); + } + if (telnet->opt_states[o_they_sga.index] == INACTIVE) { + telnet->opt_states[o_they_sga.index] = REQUESTED; + send_opt(telnet, o_they_sga.send, o_they_sga.option); + } + telnet->activated = TRUE; + } +} + +static void activate_option(Telnet telnet, const struct Opt *o) +{ + if (o->send == WILL && o->option == TELOPT_NAWS) + telnet_size(telnet, telnet->term_width, telnet->term_height); + if (o->send == WILL && + (o->option == TELOPT_NEW_ENVIRON || + o->option == TELOPT_OLD_ENVIRON)) { + /* + * We may only have one kind of ENVIRON going at a time. + * This is a hack, but who cares. + */ + deactivate_option(telnet, o->option == + TELOPT_NEW_ENVIRON ? &o_oenv : &o_nenv); + } + option_side_effects(telnet, o, 1); +} + +static void refused_option(Telnet telnet, const struct Opt *o) +{ + if (o->send == WILL && o->option == TELOPT_NEW_ENVIRON && + telnet->opt_states[o_oenv.index] == INACTIVE) { + send_opt(telnet, WILL, TELOPT_OLD_ENVIRON); + telnet->opt_states[o_oenv.index] = REQUESTED; + } + option_side_effects(telnet, o, 0); +} + +static void proc_rec_opt(Telnet telnet, int cmd, int option) +{ + const struct Opt *const *o; + + log_option(telnet, "server", cmd, option); + for (o = opts; *o; o++) { + if ((*o)->option == option && (*o)->ack == cmd) { + switch (telnet->opt_states[(*o)->index]) { + case REQUESTED: + telnet->opt_states[(*o)->index] = ACTIVE; + activate_option(telnet, *o); + break; + case ACTIVE: + break; + case INACTIVE: + telnet->opt_states[(*o)->index] = ACTIVE; + send_opt(telnet, (*o)->send, option); + activate_option(telnet, *o); + break; + case REALLY_INACTIVE: + send_opt(telnet, (*o)->nsend, option); + break; + } + return; + } else if ((*o)->option == option && (*o)->nak == cmd) { + switch (telnet->opt_states[(*o)->index]) { + case REQUESTED: + telnet->opt_states[(*o)->index] = INACTIVE; + refused_option(telnet, *o); + break; + case ACTIVE: + telnet->opt_states[(*o)->index] = INACTIVE; + send_opt(telnet, (*o)->nsend, option); + option_side_effects(telnet, *o, 0); + break; + case INACTIVE: + case REALLY_INACTIVE: + break; + } + return; + } + } + /* + * If we reach here, the option was one we weren't prepared to + * 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. + */ + if (cmd == WILL || cmd == DO) + send_opt(telnet, (cmd == WILL ? DONT : WONT), option); +} + +static void process_subneg(Telnet telnet) +{ + unsigned char b[2048], *p, *q; + int var, value, n; + char *e; + + switch (telnet->sb_opt) { + case TELOPT_TSPEED: + if (telnet->sb_len == 1 && telnet->sb_buf[0] == TELQUAL_SEND) { + char *logbuf; + 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); + 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); + logevent(telnet->frontend, logbuf); + sfree(logbuf); + } else + logevent(telnet->frontend, "server:\tSB TSPEED "); + break; + case TELOPT_TTYPE: + if (telnet->sb_len == 1 && telnet->sb_buf[0] == TELQUAL_SEND) { + char *logbuf; + 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]); + b[n + 4] = IAC; + b[n + 5] = SE; + telnet->bufsize = sk_write(telnet->s, (char *)b, n + 6); + b[n + 4] = 0; + logevent(telnet->frontend, "server:\tSB TTYPE SEND"); + logbuf = dupprintf("client:\tSB TTYPE IS %s", b + 4); + logevent(telnet->frontend, logbuf); + sfree(logbuf); + } else + logevent(telnet->frontend, "server:\tSB TTYPE \r\n"); + break; + case TELOPT_OLD_ENVIRON: + case TELOPT_NEW_ENVIRON: + p = telnet->sb_buf; + q = p + telnet->sb_len; + if (p < q && *p == TELQUAL_SEND) { + char *logbuf; + p++; + logbuf = dupprintf("server:\tSB %s SEND", telopt(telnet->sb_opt)); + logevent(telnet->frontend, logbuf); + sfree(logbuf); + if (telnet->sb_opt == TELOPT_OLD_ENVIRON) { + if (telnet->cfg.rfc_environ) { + value = RFC_VALUE; + var = RFC_VAR; + } else { + value = BSD_VALUE; + var = BSD_VAR; + } + /* + * Try to guess the sense of VAR and VALUE. + */ + while (p < q) { + if (*p == RFC_VAR) { + value = RFC_VALUE; + var = RFC_VAR; + } else if (*p == BSD_VAR) { + value = BSD_VALUE; + var = BSD_VAR; + } + p++; + } + } else { + /* + * With NEW_ENVIRON, the sense of VAR and VALUE + * isn't in doubt. + */ + value = RFC_VALUE; + var = RFC_VAR; + } + b[0] = IAC; + b[1] = SB; + b[2] = telnet->sb_opt; + b[3] = TELQUAL_IS; + n = 4; + e = telnet->cfg.environmt; + while (*e) { + b[n++] = var; + while (*e && *e != '\t') + b[n++] = *e++; + if (*e == '\t') + e++; + b[n++] = value; + while (*e) + b[n++] = *e++; + e++; + } + { + char user[sizeof(telnet->cfg.username)]; + (void) get_remote_username(&telnet->cfg, user, sizeof(user)); + if (*user) { + b[n++] = var; + b[n++] = 'U'; + b[n++] = 'S'; + b[n++] = 'E'; + b[n++] = 'R'; + b[n++] = value; + e = user; + while (*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), + *user ? "USER=" : "", + user, + *user ? " " : "", + n == 6 ? "" : + (*telnet->cfg.environmt ? "" : "")); + logevent(telnet->frontend, logbuf); + sfree(logbuf); + } + } + break; + } +} + +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++; + + switch (telnet->state) { + case TOP_LEVEL: + case SEENCR: + if (c == NUL && telnet->state == SEENCR) + telnet->state = TOP_LEVEL; + else if (c == IAC) + telnet->state = SEENIAC; + else { + if (!telnet->in_synch) + ADDTOBUF(c); + +#if 1 + /* I can't get the F***ing winsock to insert the urgent IAC + * into the right position! Even with SO_OOBINLINE it gives + * it to recv too soon. And of course the DM byte (that + * arrives in the same packet!) appears several K later!! + * + * Oh well, we do get the DM in the right place so I'll + * just stop hiding on the next 0xf2 and hope for the best. + */ + else if (c == DM) + telnet->in_synch = 0; +#endif + if (c == CR && telnet->opt_states[o_they_bin.index] != ACTIVE) + telnet->state = SEENCR; + else + telnet->state = TOP_LEVEL; + } + break; + case SEENIAC: + if (c == DO) + telnet->state = SEENDO; + else if (c == DONT) + telnet->state = SEENDONT; + else if (c == WILL) + telnet->state = SEENWILL; + else if (c == WONT) + telnet->state = SEENWONT; + else if (c == SB) + telnet->state = SEENSB; + else if (c == DM) { + telnet->in_synch = 0; + telnet->state = TOP_LEVEL; + } else { + /* ignore everything else; print it if it's IAC */ + if (c == IAC) { + ADDTOBUF(c); + } + telnet->state = TOP_LEVEL; + } + break; + case SEENWILL: + proc_rec_opt(telnet, WILL, c); + telnet->state = TOP_LEVEL; + break; + case SEENWONT: + proc_rec_opt(telnet, WONT, c); + telnet->state = TOP_LEVEL; + break; + case SEENDO: + proc_rec_opt(telnet, DO, c); + telnet->state = TOP_LEVEL; + break; + case SEENDONT: + proc_rec_opt(telnet, DONT, c); + telnet->state = TOP_LEVEL; + break; + case SEENSB: + telnet->sb_opt = c; + telnet->sb_len = 0; + telnet->state = SUBNEGOT; + break; + case SUBNEGOT: + if (c == IAC) + telnet->state = SUBNEG_IAC; + else { + subneg_addchar: + if (telnet->sb_len >= telnet->sb_size) { + telnet->sb_size += SB_DELTA; + telnet->sb_buf = sresize(telnet->sb_buf, telnet->sb_size, + unsigned char); + } + telnet->sb_buf[telnet->sb_len++] = c; + telnet->state = SUBNEGOT; /* in case we came here by goto */ + } + break; + case SUBNEG_IAC: + if (c != SE) + goto subneg_addchar; /* yes, it's a hack, I know, but... */ + else { + process_subneg(telnet); + telnet->state = TOP_LEVEL; + } + 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, + int calling_back) +{ + Telnet telnet = (Telnet) plug; + + if (telnet->s) { + sk_close(telnet->s); + telnet->s = NULL; + notify_remote_exit(telnet->frontend); + } + if (error_msg) { + logevent(telnet->frontend, error_msg); + connection_fatal(telnet->frontend, "%s", error_msg); + } + /* Otherwise, the remote side closed the connection normally. */ + return 0; +} + +static int telnet_receive(Plug plug, int urgent, char *data, int len) +{ + Telnet telnet = (Telnet) plug; + if (urgent) + telnet->in_synch = TRUE; + do_telnet_read(telnet, data, len); + return 1; +} + +static void telnet_sent(Plug plug, int bufsize) +{ + Telnet telnet = (Telnet) plug; + telnet->bufsize = bufsize; +} + +/* + * Called to set up the Telnet connection. + * + * Returns an error message, or NULL on success. + * + * Also places the canonical host name into `realhost'. It must be + * 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) +{ + static const struct plug_function_table fn_table = { + telnet_log, + telnet_closing, + telnet_receive, + telnet_sent + }; + SockAddr addr; + const char *err; + Telnet telnet; + + telnet = snew(struct telnet_tag); + telnet->fn = &fn_table; + telnet->cfg = *cfg; /* STRUCTURE COPY */ + telnet->s = NULL; + 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->state = TOP_LEVEL; + telnet->ldisc = NULL; + telnet->pinger = NULL; + *backend_handle = telnet; + + /* + * Try to find host. + */ + { + char *buf; + 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, cfg->addressfamily); + if ((err = sk_addr_error(addr)) != NULL) { + sk_addr_free(addr); + return err; + } + + if (port < 0) + port = 23; /* default telnet port */ + + /* + * Open socket. + */ + telnet->s = new_connection(addr, *realhost, port, 0, 1, + nodelay, keepalive, (Plug) telnet, &telnet->cfg); + if ((err = sk_socket_error(telnet->s)) != NULL) + return err; + + telnet->pinger = pinger_new(&telnet->cfg, &telnet_backend, telnet); + + /* + * Initialise option states. + */ + if (telnet->cfg.passive_telnet) { + const struct Opt *const *o; + + for (o = opts; *o; o++) + telnet->opt_states[(*o)->index] = INACTIVE; + } else { + const struct Opt *const *o; + + for (o = opts; *o; o++) { + telnet->opt_states[(*o)->index] = (*o)->initial_state; + if (telnet->opt_states[(*o)->index] == REQUESTED) + send_opt(telnet, (*o)->send, (*o)->option); + } + telnet->activated = TRUE; + } + + /* + * Set up SYNCH state. + */ + telnet->in_synch = FALSE; + + /* + * We can send special commands from the start. + */ + 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; +} + +static void telnet_free(void *handle) +{ + Telnet telnet = (Telnet) handle; + + sfree(telnet->sb_buf); + if (telnet->s) + sk_close(telnet->s); + if (telnet->pinger) + pinger_free(telnet->pinger); + sfree(telnet); +} +/* + * Reconfigure the Telnet backend. There's no immediate action + * necessary, in this backend: we just save the fresh config for + * any subsequent negotiations. + */ +static void telnet_reconfig(void *handle, Config *cfg) +{ + Telnet telnet = (Telnet) handle; + pinger_reconfig(telnet->pinger, &telnet->cfg, cfg); + telnet->cfg = *cfg; /* STRUCTURE COPY */ +} + +/* + * Called to send data down the Telnet connection. + */ +static int telnet_send(void *handle, char *buf, int len) +{ + Telnet telnet = (Telnet) handle; + unsigned char *p, *end; + static const unsigned char iac[2] = { IAC, IAC }; + static const unsigned char cr[2] = { CR, NUL }; +#if 0 + static const unsigned char nl[2] = { CR, LF }; +#endif + + if (telnet->s == NULL) + return 0; + + p = (unsigned char *)buf; + end = (unsigned char *)(buf + len); + while (p < end) { + unsigned char *q = p; + + while (p < end && iswritable(*p)) + p++; + telnet->bufsize = sk_write(telnet->s, (char *)q, p - q); + + while (p < end && !iswritable(*p)) { + telnet->bufsize = + sk_write(telnet->s, (char *)(*p == IAC ? iac : cr), 2); + p++; + } + } + + return telnet->bufsize; +} + +/* + * Called to query the current socket sendability status. + */ +static int telnet_sendbuffer(void *handle) +{ + Telnet telnet = (Telnet) handle; + return telnet->bufsize; +} + +/* + * Called to set the size of the window from Telnet's POV. + */ +static void telnet_size(void *handle, int width, int height) +{ + Telnet telnet = (Telnet) handle; + unsigned char b[24]; + int n; + char *logbuf; + + telnet->term_width = width; + telnet->term_height = height; + + if (telnet->s == NULL || telnet->opt_states[o_naws.index] != ACTIVE) + return; + n = 0; + b[n++] = IAC; + b[n++] = SB; + b[n++] = TELOPT_NAWS; + b[n++] = telnet->term_width >> 8; + if (b[n-1] == IAC) b[n++] = IAC; /* duplicate any IAC byte occurs */ + b[n++] = telnet->term_width & 0xFF; + if (b[n-1] == IAC) b[n++] = IAC; /* duplicate any IAC byte occurs */ + b[n++] = telnet->term_height >> 8; + if (b[n-1] == IAC) b[n++] = IAC; /* duplicate any IAC byte occurs */ + b[n++] = telnet->term_height & 0xFF; + if (b[n-1] == IAC) b[n++] = IAC; /* duplicate any IAC byte occurs */ + b[n++] = IAC; + b[n++] = SE; + telnet->bufsize = sk_write(telnet->s, (char *)b, n); + logbuf = dupprintf("client:\tSB NAWS %d,%d", + telnet->term_width, telnet->term_height); + logevent(telnet->frontend, logbuf); + sfree(logbuf); +} + +/* + * Send Telnet special codes. + */ +static void telnet_special(void *handle, Telnet_Special code) +{ + Telnet telnet = (Telnet) handle; + unsigned char b[2]; + + if (telnet->s == NULL) + return; + + b[0] = IAC; + switch (code) { + case TS_AYT: + b[1] = AYT; + telnet->bufsize = sk_write(telnet->s, (char *)b, 2); + break; + case TS_BRK: + b[1] = BREAK; + telnet->bufsize = sk_write(telnet->s, (char *)b, 2); + break; + case TS_EC: + b[1] = EC; + telnet->bufsize = sk_write(telnet->s, (char *)b, 2); + break; + case TS_EL: + b[1] = EL; + telnet->bufsize = sk_write(telnet->s, (char *)b, 2); + break; + case TS_GA: + b[1] = GA; + telnet->bufsize = sk_write(telnet->s, (char *)b, 2); + break; + case TS_NOP: + b[1] = NOP; + telnet->bufsize = sk_write(telnet->s, (char *)b, 2); + break; + case TS_ABORT: + b[1] = ABORT; + telnet->bufsize = sk_write(telnet->s, (char *)b, 2); + break; + case TS_AO: + b[1] = AO; + telnet->bufsize = sk_write(telnet->s, (char *)b, 2); + break; + case TS_IP: + b[1] = IP; + telnet->bufsize = sk_write(telnet->s, (char *)b, 2); + break; + case TS_SUSP: + b[1] = SUSP; + telnet->bufsize = sk_write(telnet->s, (char *)b, 2); + break; + case TS_EOR: + b[1] = EOR; + telnet->bufsize = sk_write(telnet->s, (char *)b, 2); + break; + case TS_EOF: + b[1] = xEOF; + telnet->bufsize = sk_write(telnet->s, (char *)b, 2); + break; + case TS_EOL: + /* In BINARY mode, CR-LF becomes just CR - + * and without the NUL suffix too. */ + if (telnet->opt_states[o_we_bin.index] == ACTIVE) + telnet->bufsize = sk_write(telnet->s, "\r", 1); + else + telnet->bufsize = sk_write(telnet->s, "\r\n", 2); + break; + case TS_SYNCH: + b[1] = DM; + telnet->bufsize = sk_write(telnet->s, (char *)b, 1); + telnet->bufsize = sk_write_oob(telnet->s, (char *)(b + 1), 1); + break; + case TS_RECHO: + if (telnet->opt_states[o_echo.index] == INACTIVE || + telnet->opt_states[o_echo.index] == REALLY_INACTIVE) { + telnet->opt_states[o_echo.index] = REQUESTED; + send_opt(telnet, o_echo.send, o_echo.option); + } + break; + case TS_LECHO: + if (telnet->opt_states[o_echo.index] == ACTIVE) { + telnet->opt_states[o_echo.index] = REQUESTED; + send_opt(telnet, o_echo.nsend, o_echo.option); + } + break; + case TS_PING: + if (telnet->opt_states[o_they_sga.index] == ACTIVE) { + b[1] = NOP; + telnet->bufsize = sk_write(telnet->s, (char *)b, 2); + } + break; + default: + break; /* never heard of it */ + } +} + +static const struct telnet_special *telnet_get_specials(void *handle) +{ + static const struct telnet_special specials[] = { + {"Are You There", TS_AYT}, + {"Break", TS_BRK}, + {"Synch", TS_SYNCH}, + {"Erase Character", TS_EC}, + {"Erase Line", TS_EL}, + {"Go Ahead", TS_GA}, + {"No Operation", TS_NOP}, + {NULL, TS_SEP}, + {"Abort Process", TS_ABORT}, + {"Abort Output", TS_AO}, + {"Interrupt Process", TS_IP}, + {"Suspend Process", TS_SUSP}, + {NULL, TS_SEP}, + {"End Of Record", TS_EOR}, + {"End Of File", TS_EOF}, + {NULL, TS_EXITMENU} + }; + return specials; +} + +static int telnet_connected(void *handle) +{ + Telnet telnet = (Telnet) handle; + return telnet->s != NULL; +} + +static int telnet_sendok(void *handle) +{ + /* Telnet telnet = (Telnet) handle; */ + return 1; +} + +static void telnet_unthrottle(void *handle, int backlog) +{ + Telnet telnet = (Telnet) handle; + sk_set_frozen(telnet->s, backlog > TELNET_MAX_BACKLOG); +} + +static int telnet_ldisc(void *handle, int option) +{ + Telnet telnet = (Telnet) handle; + if (option == LD_ECHO) + return telnet->echoing; + if (option == LD_EDIT) + return telnet->editing; + return FALSE; +} + +static void telnet_provide_ldisc(void *handle, void *ldisc) +{ + Telnet telnet = (Telnet) handle; + telnet->ldisc = ldisc; +} + +static void telnet_provide_logctx(void *handle, void *logctx) +{ + /* This is a stub. */ +} + +static int telnet_exitcode(void *handle) +{ + Telnet telnet = (Telnet) handle; + if (telnet->s != NULL) + return -1; /* still connected */ + else + /* Telnet doesn't transmit exit codes back to the client */ + 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, + telnet_reconfig, + telnet_send, + telnet_sendbuffer, + telnet_size, + telnet_special, + telnet_get_specials, + telnet_connected, + telnet_exitcode, + telnet_sendok, + telnet_ldisc, + telnet_provide_ldisc, + telnet_provide_logctx, + telnet_unthrottle, + telnet_cfg_info, + "telnet", + PROT_TELNET, + 23 +}; -- cgit v1.2.3