diff options
Diffstat (limited to 'tcp.c')
| -rw-r--r-- | tcp.c | 1045 |
1 files changed, 0 insertions, 1045 deletions
@@ -1,1045 +0,0 @@ -/* - * tcp.c -- telnet protocol communication module for powwow - * - * Copyright (C) 1998,2002 by Massimiliano Ghilardi - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - */ - -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <signal.h> -#include <errno.h> -#include <fcntl.h> -#include <signal.h> -#include <sys/types.h> -#include <sys/socket.h> -#include <sys/time.h> -#include <netdb.h> -#include <netinet/in.h> -#include <netinet/tcp.h> -#include <arpa/telnet.h> -#ifndef TELOPT_NAWS -# define TELOPT_NAWS 31 -#endif -#include <arpa/inet.h> -#ifndef NEXT -# include <unistd.h> -#endif - -#ifdef TERM -# include "client.h" -#endif - -#include "defines.h" -#include "main.h" -#include "utils.h" -#include "tcp.h" -#include "tty.h" -#include "edit.h" -#include "beam.h" -#include "log.h" - -#ifdef TELOPTS -# define TELOPTSTR(n) ((n) > NTELOPTS ? "unknown" : telopts[n]) -#endif - -int tcp_fd = -1; /* current socket file descriptor - * -1 means no socket */ -int tcp_main_fd = -1; /* socket file descriptor of main connect. - * -1 means no socket */ -int tcp_max_fd = 0; /* highest used fd */ - -int tcp_count = 0; /* number of open connections */ -int tcp_attachcount = 0; /* number of spawned commands */ - -int conn_max_index; /* 1 + highest used conn_list[] index */ - -connsess conn_list[MAX_CONNECTS]; /* connection list */ - -byte conn_table[MAX_FDSCAN]; /* fd -> index translation table */ - -fd_set fdset; /* set of descriptors to select() on */ - -/* - * process suboptions. - * so far, only terminal type is processed but future extensions are - * window size, X display location, etc. - */ -static void dosubopt(byte *str) -{ - char buf[256], *term; - int len, err; - - if (str[0] == TELOPT_TTYPE) { - if (str[1] == 1) { - /* 1 == SEND */ -#ifdef TELOPTS - tty_printf("[got SB TERMINAL TYPE SEND]\n"); -#endif - if (!(term = getenv("TERM"))) term = "unknown"; - sprintf(buf, "%c%c%c%c%.*s%c%c", IAC, SB, TELOPT_TTYPE, 0, - 256-7, term, IAC, SE); /* 0 == IS */ - - len = strlen(term) + 6; - while ((err = write(tcp_fd, buf, len)) < 0 && errno == EINTR) - ; - if (err != len) { - errmsg("write subopt to socket"); - return; - } -#ifdef TELOPTS - tty_printf("[sent SB TERMINAL TYPE IS %s]\n", term); -#endif - } - } -} - -/* - * send an option negotiation - * 'what' is one of WILL, WONT, DO, DONT - */ -static void sendopt(byte what, byte opt) -{ - static byte buf[3] = { IAC, 0, 0 }; - int i; - buf[1] = what; buf[2] = opt; - - while ((i = write(tcp_fd, buf, 3)) < 0 && errno == EINTR) - ; - if (i != 3) { - errmsg("write option to socket"); - return; - } - -#ifdef TELOPTS - tty_printf("[sent %s %s]\n", (what == WILL) ? "WILL" : - (what == WONT) ? "WONT" : - (what == DO) ? "DO" : (what == DONT) ? "DONT" : "error", - TELOPTSTR(opt)); -#endif -} - -/* - * connect to remote host - * Warning: some voodoo code here - */ -int tcp_connect(const char *addr, int port) -{ - struct addrinfo *host_info; - struct addrinfo addrinfo; - struct sockaddr_in6 address; - int err, newtcp_fd; - - status(1); - - memset(&address, 0, sizeof address); - memset(&addrinfo, 0, sizeof addrinfo); - - /* - * inet_addr has a strange design: It is documented to return -1 for - * malformed requests, but it is declared to return unsigned long! - * Anyway, this works. - */ - -#ifndef TERM - switch (inet_pton(AF_INET6, addr, &address.sin6_addr)) - { - case -1: - perror("inet_pton()"); - return -1; - case 1: - address.sin6_family = AF_INET6; - addrinfo.ai_family = AF_INET6; - addrinfo.ai_socktype = SOCK_STREAM; - addrinfo.ai_addr = (struct sockaddr *)&address; - addrinfo.ai_addrlen = sizeof address; - host_info = &addrinfo; - break; - case 0: - if (opt_info) - tty_printf("#looking up %s... ", addr); - tty_flush(); - addrinfo.ai_family = AF_INET6; - addrinfo.ai_socktype = SOCK_STREAM; - addrinfo.ai_flags = AI_V4MAPPED; - int gai = getaddrinfo(addr, NULL, &addrinfo, &host_info); - if (gai != 0) { - tty_printf("failed to look up host: %s\n", - gai_strerror(gai)); - return -1; - } - if (opt_info) - tty_puts("found.\n"); - break; - default: - abort(); - } - - for (; host_info; host_info = host_info->ai_next) { - newtcp_fd = socket(host_info->ai_family, host_info->ai_socktype, 0); - if (newtcp_fd == -1) - continue; - if (newtcp_fd >= MAX_FDSCAN) { - tty_printf("#connect: #error: too many open connections\n"); - close(newtcp_fd); - return -1; - } - - tty_printf("#trying %s... ", addr); - tty_flush(); - - ((struct sockaddr_in6 *)host_info->ai_addr)->sin6_port = htons(port); - - err = connect(newtcp_fd, host_info->ai_addr, host_info->ai_addrlen); - - if (err == -1) { /* CTRL-C pressed, or other errors */ - errmsg("connect to host"); - close(newtcp_fd); - return -1; - } - break; - } - - if (host_info == NULL) { - errmsg("failed to connect"); - return -1; - } - -#else /* term */ - - if ((newtcp_fd = connect_server(0)) < 0) { - tty_puts("\n#powwow: unable to connect to term server\n"); - return -1; - } else { - if (newtcp_fd >= MAX_FDSCAN) { - tty_printf("#connect: #error: too many open connections\n"); - close(newtcp_fd); - return -1; - } - send_command(newtcp_fd, C_PORT, 0, "%s:%d", addr, port); - tty_puts("Connected to term server...\n"); -#ifdef TERM_COMPRESS - send_command(newtcp_fd, C_COMPRESS, 1, "y"); -#endif - send_command(newtcp_fd, C_DUMB, 1, 0); - } - -#endif /* term */ - - tty_puts("connected!\n"); - - - { - /* - * Now set some options on newtcp_fd : - * First, no-nagle - */ - int opt = 1; -# ifndef SOL_TCP -# define SOL_TCP IPPROTO_TCP -# endif - if (setsockopt(newtcp_fd, SOL_TCP, TCP_NODELAY, &opt, sizeof(opt))) - errmsg("setsockopt(TCP_NODELAY) failed"); - - /* TCP keep-alive */ - if (setsockopt(newtcp_fd, SOL_SOCKET, SO_KEEPALIVE, &opt, sizeof(opt))) - errmsg("setsockopt(SO_KEEPALIVE) failed"); - - /* - * Then, close-on-exec: - * we don't want children to inherit the socket! - */ - - fcntl(newtcp_fd, F_SETFD, FD_CLOEXEC); - } - - return newtcp_fd; -} - -/* - * we don't expect IAC commands here, except IAC IAC (a protected ASCII 255) - * which we replace with a single IAC (a plain ASCII 255) - */ -int tcp_unIAC(char *buffer, int len) -{ - char *s, *start, warnIACs = 1; - if (!memchr(buffer, IAC, len)) - return len; - - for (s = start = buffer; len > 0; buffer++, len--) { - if (buffer[0] == (char)(byte)IAC) { - if (len > 1 && buffer[1] == (char)(byte)IAC) - buffer++, len--; - else if (warnIACs) { - PRINTF("#warning: received IAC inside MPI message, treating as IAC IAC.\n"); - warnIACs = 0; - } - } - *s++ = *buffer; - } - return s - start; -} - -/* - * read a maximum of size chars from remote host - * using the telnet protocol. return chars read. - */ -int tcp_read(int fd, char *buffer, int maxsize) -{ - char state = CONN_LIST(fd).state; - char old_state = CONN_LIST(fd).old_state; - int i; - static byte subopt[MAX_SUBOPT]; - static int subchars; - byte *p, *s, *linestart; - - char *ibuffer = buffer; - if (state == GOT_R) { - /* make room for the leading \r */ - ++ibuffer; - --maxsize; - } - - while ((i = read(fd, ibuffer, maxsize)) < 0 && errno == EINTR) - ; - - if (i == 0) { - CONN_LIST(fd).state = NORMAL; - tcp_close(NULL); - return 0; - } - if (i < 0) { - errmsg("read from socket"); - return 0; - } - - /* - * scan through the buffer, - * interpret telnet protocol escapes and MUME MPI messages - */ - p = (byte *)buffer; - for (s = linestart = (byte *)ibuffer; i; s++, i--) { - switch (state) { - case NORMAL: - case ALTNORMAL: - case GOT_R: - case GOT_N: - /* - * Some servers like to send NULs and other funny chars. - * Clean up as much as possible. - */ - switch (*s) { - case IAC: - old_state = state; /* remember state to return to after IAC processing */ - state = GOTIAC; - break; - case '\r': - /* start counting \r, unless just got \n */ - if (state == NORMAL || state == ALTNORMAL) { - /* - * ALTNORMAL is safe here: \r cannot be in MPI header, - * and any previous MPI header has already been rejected - */ - state = GOT_R; - } else if (state == GOT_N) - /* after \n\r, we forbid MPI messages */ - state = ALTNORMAL; - break; - case '\n': - state = GOT_N; - *p++ = *s; - linestart = p; - break; - case '\0': - /* skip NULs */ - break; - default: - /* first, flush any missing \r */ - if (state == GOT_R) - *p++ = '\r'; - - *p++ = *s; - - /* check for MUME MPI messages: */ - if (p - linestart == MPILEN && !memcmp(linestart, MPI, MPILEN)) { - if (!(CONN_LIST(fd).flags & IDEDITOR)) { - PRINTF("#warning: MPI message received without #request editor!\n"); - } else if (state == ALTNORMAL) { - /* no MPI messages after \n\r */ - PRINTF("#warning: MPI attack?\n"); - } else { - subchars = process_message((char*)s+1, i-1); - /* no +MPILEN here, as it was already processed. */ - s += subchars; i-= subchars; - p = linestart; - } - } - - if (state != ALTNORMAL) - state = NORMAL; - break; - } - break; - - case GOTIAC: - switch (*s) { - case WILL: - state = GOTWILL; break; - case WONT: - state = GOTWONT; break; - case DO: - state = GOTDO; break; - case DONT: - state = GOTDONT; break; - case SB: /* BUG (multiple connections): */ - state = GOTSB; /* there is only one subopt buffer */ - subchars = 0; - break; - case IAC: - *p++ = IAC; - state = old_state; - break; - case GA: - /* I should handle GA as end-of-prompt marker one day */ - /* one day has come ;) - Max */ - prompt_set_iac((char*)p); - state = old_state; - break; - default: - /* ignore the rest of the telnet commands */ -#ifdef TELOPTS - tty_printf("[skipped IAC <%d>]\n", *s); -#endif - state = old_state; - break; - } - break; - - case GOTWILL: -#ifdef TELOPTS - tty_printf("[got WILL %s]\n", TELOPTSTR(*s)); -#endif - switch(*s) { - case TELOPT_ECHO: - /* host echoes, turn off echo here - * but only for main connection, since we do not want - * subsidiary connection password entries to block anything - * in the main connection - */ - if (fd == tcp_main_fd) - linemode |= LM_NOECHO; - sendopt(DO, *s); - break; - case TELOPT_SGA: - /* this can't hurt */ - linemode |= LM_CHAR; - tty_special_keys(); - sendopt(DO, *s); - break; - default: - /* don't accept other options */ - sendopt(DONT, *s); - break; - } - state = old_state; - break; - - case GOTWONT: -#ifdef TELOPTS - tty_printf("[got WONT %s]\n", TELOPTSTR(*s)); -#endif - if (*s == TELOPT_ECHO) { - /* host no longer echoes, we do it instead */ - linemode &= ~LM_NOECHO; - } - /* accept any WONT */ - sendopt(DONT, *s); - state = old_state; - break; - - case GOTDO: -#ifdef TELOPTS - tty_printf("[got DO %s]\n", TELOPTSTR(*s)); -#endif - switch(*s) { - case TELOPT_SGA: - linemode |= LM_CHAR; - tty_special_keys(); - /* FALLTHROUGH */ - case TELOPT_TTYPE: - sendopt(WILL, *s); - break; - case TELOPT_NAWS: - sendopt(WILL, *s); - tcp_write_tty_size(); - break; - default: - /* accept nothing else */ - sendopt(WONT, *s); - break; - } - state = old_state; - break; - - case GOTDONT: -#ifdef TELOPTS - tty_printf("[got DONT %s]\n", TELOPTSTR(*s)); -#endif - if (*s == TELOPT_SGA) { - linemode &= ~LM_CHAR; - tty_special_keys(); - } - sendopt(WONT, *s); - state = old_state; - break; - - case GOTSB: - if (*s == IAC) { - state = GOTSBIAC; - } else { - if (subchars < MAX_SUBOPT) - subopt[subchars++] = *s; - } - break; - - case GOTSBIAC: - if (*s == IAC) { - if (subchars < MAX_SUBOPT) - subopt[subchars++] = IAC; - state = GOTSB; - } else if (*s == SE) { - subopt[subchars] = '\0'; - dosubopt(subopt); - state = old_state; - } else { - /* problem! I haven't the foggiest idea of what to do here. - * I'll just ignore it and hope it goes away. */ - PRINTF("#telnet: got IAC <%d> instead of IAC SE!\n", (int)*s); - state = old_state; - } - break; - } - } - CONN_LIST(fd).state = state; - CONN_LIST(fd).old_state = old_state; - - if (!(CONN_LIST(tcp_fd).flags & SPAWN)) { - log_write(buffer, (char *)p - buffer, 0); - } - - return (char *)p - buffer; -} - -static void internal_tcp_raw_write(int fd, const char *data, int len) -{ - while (len > 0) { - int i; - while ((i = write(fd, data, len)) < 0 && errno == EINTR) - ; - if (i < 0) { - errmsg("write to socket"); - break; - } - data += i; - len -= i; - } -} - -void tcp_raw_write(int fd, const char *data, int len) -{ - tcp_flush(); - internal_tcp_raw_write(fd, data, len); -} - -/* write data, escape any IACs */ -void tcp_write_escape_iac(int fd, const char *data, int len) -{ - tcp_flush(); - - for (;;) { - const char *iac = memchr(data, IAC, len); - size_t l = iac ? (iac - data) + 1 : len; - internal_tcp_raw_write(fd, data, l); - if (iac == NULL) - return; - internal_tcp_raw_write(fd, iac, 1); - len -= l; - data = iac + 1; - } -} - -/* - * Send current terminal size (RFC 1073) - */ -void tcp_write_tty_size(void) -{ - static byte buf[] = { IAC, SB, TELOPT_NAWS, 0, 0, 0, 0, IAC, SE }; - - buf[3] = cols >> 8; - buf[4] = cols & 0xff; - buf[5] = lines >> 8; - buf[6] = lines & 0xff; - - tcp_raw_write(tcp_main_fd, (char *)buf, 9); -#ifdef TELOPTS - tty_printf("[sent term size %d %d]\n", cols, lines); -#endif -} - -/* - * send a string to the main connection on the remote host - */ -void tcp_main_write(char *data) -{ - tcp_write(tcp_main_fd, data); -} - - -static char output_buffer[BUFSIZE]; -static int output_len = 0; /* number of characters in output_buffer */ -static int output_socket = -1; /* to which socket buffer should be sent*/ - -/* - * put data in the output buffer for transmission to the remote host - */ -void tcp_write(int fd, char *data) -{ - char *iacs, *out; - int len, space, iacp; - len = strlen(data); - - if (tcp_main_fd != -1 && tcp_main_fd == fd) { - if (linemode & LM_NOECHO) - log_write("", 0, 1); /* log a newline only */ - else - log_write(data, len, 1); - reprint_writeline(data); - } - - /* must be AFTER reprint_writeline() */ - if (CONN_LIST(tcp_fd).flags & SPAWN) - status(1); - else - status(-1); - - if (fd != output_socket) { /* is there data to another socket? */ - tcp_flush(); /* then flush it */ - output_socket = fd; - } - - out = output_buffer + output_len; - space = BUFSIZE - output_len; - - while (len) { - iacs = memchr(data, IAC, len); - iacp = iacs ? iacs - data : len; - - if (iacp == 0) { - /* we're at the IAC, send it */ - if (space < 2) { - tcp_flush(); - out = output_buffer; - space = BUFSIZE; - } - *out++ = (char)IAC; *out++ = (char)IAC; output_len += 2; space -= 2; - data++; len--; - continue; - } - - while (space < iacp) { - memcpy(out, data, space); - data += space; len -= space; - iacp -= space; - output_len = BUFSIZE; - - tcp_flush(); - out = output_buffer; - space = BUFSIZE; - } - - if (iacp /* && space >= iacp */ ) { - memcpy(out, data, iacp); - out += iacp; output_len += iacp; space -= iacp; - data += iacp; len -= iacp; - } - } - if (!space) { - tcp_flush(); - out = output_buffer; - } - *out++ = '\n'; - output_len++; -} - -/* - * send all buffered data to the remote host - */ -void tcp_flush(void) -{ - int n; - char *p = output_buffer; - - if (output_len && output_socket == -1) { - clear_input_line(1); - PRINTF("#no open connections. Use '#connect main <address> <port>' to open a connection.\n"); - output_len = 0; - return; - } - - if (!output_len) - return; - - while (output_len) { - while ((n = write(output_socket, p, output_len)) < 0 && errno == EINTR) - ; - if (n < 0) { - output_len = 0; - errmsg("write to socket"); - return; - } - sent += n; - p += n; - output_len -= n; - } - - if (CONN_LIST(output_socket).flags & SPAWN) - status(1); - else - /* sent stuff, so we expect a prompt */ - status(-1); -} - -/* - * Below are multiple-connection support functions: - */ - -/* - * return connection's fd given id, - * or -1 if null or invalid id is given - */ -int tcp_find(char *id) -{ - int i; - - for (i=0; i<conn_max_index; i++) { - if (CONN_INDEX(i).id && !strcmp(CONN_INDEX(i).id, id)) - return CONN_INDEX(i).fd; - } - return -1; -} - -/* - * show list of open connections - */ -void tcp_show(void) -{ - int i = tcp_count + tcp_attachcount; - - PRINTF("#%s connection%s opened%c\n", i ? "The following" : "No", - i==1 ? " is" : "s are", i ? ':' : '.'); - - - for (i=0; i<conn_max_index; i++) - if (CONN_INDEX(i).id && !(CONN_INDEX(i).flags & SPAWN)) { - tty_printf("MUD %sactive %s ##%s\t (%s %d)\n", - CONN_INDEX(i).flags & ACTIVE ? " " : "non", - i == tcp_main_fd ? "(default)" : " ", - CONN_INDEX(i).id, - CONN_INDEX(i).host, CONN_INDEX(i).port); - } - for (i=0; i<conn_max_index; i++) - if (CONN_INDEX(i).id && (CONN_INDEX(i).flags & SPAWN)) { - tty_printf("CMD %sactive %s ##%s\t (%s)\n", - CONN_INDEX(i).flags & ACTIVE ? " " : "non", - i == tcp_main_fd ? "(default)" : " ", - CONN_INDEX(i).id, CONN_INDEX(i).host); - } -} - -/* - * permanently change main connection - */ -void tcp_set_main(int fd) -{ - /* GH: reset linemode and prompt */ - tcp_main_fd = fd; - if (linemode & LM_CHAR) - linemode = 0, tty_special_keys(); - else - linemode = 0; - status(-1); - reprint_clear(); -} - -/* - * open another connection - */ -void tcp_open(char *id, char *initstring, char *host, int port) -{ - int newtcp_fd, i; - - if (tcp_count+tcp_attachcount >= MAX_CONNECTS) { - PRINTF("#too many open connections.\n"); - return; - } - if (tcp_find(id)>=0) { - PRINTF("#connection \"%s\" already open.\n", id); - return; - } - - /* find a free slot */ - for (i=0; i<MAX_CONNECTS; i++) { - if (!CONN_INDEX(i).id) - break; - } - if (i == MAX_CONNECTS) { - PRINTF("#internal error, connection table full :(\n"); - return; - } - - if (!(CONN_INDEX(i).host = my_strdup(host))) { - errmsg("malloc"); - return; - } - if (!(CONN_INDEX(i).id = my_strdup(id))) { - errmsg("malloc"); - free(CONN_INDEX(i).host); - return; - } - - /* dial the number by moving the right index in small circles */ - if ((newtcp_fd = tcp_connect(host, port)) < 0) { - free(CONN_INDEX(i).host); - free(CONN_INDEX(i).id); - CONN_INDEX(i).id = 0; - return; - } - - conn_table[newtcp_fd] = i; - CONN_INDEX(i).flags = ACTIVE; - CONN_INDEX(i).state = NORMAL; - CONN_INDEX(i).old_state = NORMAL; - CONN_INDEX(i).port = port; - CONN_INDEX(i).fd = newtcp_fd; - - if (tcp_max_fd < newtcp_fd) - tcp_max_fd = newtcp_fd; - if (conn_max_index <= i) - conn_max_index = i+1; - - FD_SET(newtcp_fd, &fdset); /* add socket to select() set */ - tcp_count++; - - if (opt_info && tcp_count) { - PRINTF("#default connection is now \"%s\"\n", id); - } - tcp_set_main(tcp_fd = newtcp_fd); - if (opt_sendsize) - tcp_write_tty_size(); - - if (initstring) { - parse_instruction(initstring, 0, 0, 1); - history_done = 0; - } -} - -/* - * close a connection - */ -void tcp_close(char *id) -{ - int i, sfd; - - status(1); - tty_puts(edattrend); - /* - * because we may be called from get_remote_input() - * if tcp_read gets an EOF, before edattrend is - * printed by get_remote_input() itself. - */ - - if (id) { /* #zap cmd */ - if ((sfd = tcp_find(id)) < 0) { - tty_printf("#no such connection: \"%s\"\n", id); - return; - } - } else - sfd = tcp_fd; /* connection closed by remote host */ - - shutdown(sfd, 2); - close(sfd); - - abort_edit_fd(sfd); - - tty_printf("#connection on \"%s\" closed.\n", CONN_LIST(sfd).id); - - if (sfd == tcp_main_fd) { /* main connection closed */ - if (tcp_count == 1) { /* was last connection */ - if (opt_exit) - exit_powwow(); - tty_puts("#no connections left. Type #quit to quit.\n"); - tcp_fd = tcp_main_fd = -1; - } else { - /* must find another connection and promote it to main */ - for (i=0; i<conn_max_index; i++) { - if (!CONN_INDEX(i).id || CONN_INDEX(i).fd == sfd - || (CONN_INDEX(i).flags & SPAWN)) - continue; - tty_printf("#default connection is now \"%s\"\n", CONN_INDEX(i).id); - tcp_main_fd = CONN_INDEX(i).fd; - break; - } - if (sfd == tcp_main_fd) { - tty_printf("#PANIC! internal error in tcp_close()\nQuitting.\n"); - syserr(NULL); - } - } - tcp_set_main(tcp_main_fd); - } - - if (tcp_fd == sfd) - tcp_fd = -1; /* no further I/O allowed on sfd, as we just closed it */ - - FD_CLR(sfd, &fdset); - if (CONN_LIST(sfd).flags & SPAWN) - tcp_attachcount--; - else - tcp_count--; - CONN_LIST(sfd).flags = 0; - CONN_LIST(sfd).state = NORMAL; - CONN_LIST(sfd).old_state = NORMAL; - CONN_LIST(sfd).port = 0; - free(CONN_LIST(sfd).host); CONN_LIST(sfd).host = 0; - free(CONN_LIST(sfd).id); CONN_LIST(sfd).id = 0; - if (CONN_LIST(sfd).fragment) { - free(CONN_LIST(sfd).fragment); - CONN_LIST(sfd).fragment = 0; - } - - /* recalculate conn_max_index */ - i = conn_table[sfd]; - if (i+1 == conn_max_index) { - do { - i--; - } while (i>=0 && !CONN_INDEX(i).id); - conn_max_index = i+1; - } - - /* recalculate tcp_max_fd */ - for (i = tcp_max_fd = 0; i<conn_max_index; i++) { - if (CONN_INDEX(i).id && tcp_max_fd < CONN_INDEX(i).fd) - tcp_max_fd = CONN_INDEX(i).fd; - } -} - -/* - * toggle output display from another connection - */ -void tcp_togglesnoop(char *id) -{ - int sfd; - - sfd = tcp_find(id); - if (sfd>=0) { - CONN_LIST(sfd).flags ^= ACTIVE; - if (opt_info) { - PRINTF("#connection %s is now %sactive.\n", - CONN_LIST(sfd).id, CONN_LIST(sfd).flags & ACTIVE ? "" : "non"); - } - } else { - PRINTF("#no such connection: %s\n", id); - } -} - -void tcp_spawn(char *id, char *cmd) -{ - int i, childpid, sockets[2]; - - if (tcp_find(id)>=0) { - PRINTF("#connection \"%s\" already open.\n", id); - return; - } - if (socketpair(AF_UNIX, SOCK_STREAM, 0, sockets) < 0) { - errmsg("create socketpair"); - return; - } - unescape(cmd); - - switch (childpid = fork()) { - case 0: - /* child */ - close(0); close(1); close(2); - setsid(); - dup2(sockets[1], 0); - dup2(sockets[1], 1); - dup2(sockets[1], 2); - close(sockets[0]); - close(sockets[1]); - execl("/bin/sh", "sh", "-c", cmd, NULL); - syserr("execl"); - break; - case -1: - close(sockets[0]); - close(sockets[1]); - errmsg("fork"); - return; - } - close(sockets[1]); - - /* Again, we don't want children to inherit sockets */ - fcntl(sockets[0], F_SETFD, FD_CLOEXEC); - - /* now find a free slot */ - for (i=0; i<MAX_CONNECTS; i++) { - if (!CONN_INDEX(i).id) { - conn_table[sockets[0]] = i; - break; - } - } - if (i == MAX_CONNECTS) { - PRINTF("#internal error, connection table full :(\n"); - close(sockets[0]); - return; - } - - if (!(CONN_INDEX(i).host = my_strdup(cmd))) { - errmsg("malloc"); - close(sockets[0]); - return; - } - if (!(CONN_INDEX(i).id = my_strdup(id))) { - errmsg("malloc"); - free(CONN_INDEX(i).host); - close(sockets[0]); - return; - } - CONN_INDEX(i).flags = ACTIVE | SPAWN; - CONN_INDEX(i).state = NORMAL; - CONN_INDEX(i).old_state = NORMAL; - CONN_INDEX(i).port = 0; - CONN_INDEX(i).fd = sockets[0]; - - FD_SET(sockets[0], &fdset); /* add socket to select() set */ - tcp_attachcount++; - - if (tcp_max_fd < sockets[0]) - tcp_max_fd = sockets[0]; - if (conn_max_index <= i) - conn_max_index = i+1; - - if (opt_info) { - PRINTF("#successfully spawned \"%s\" with pid %d\n", id, childpid); - } - - /* - * when the child exits we also get an EOF on the socket, - * so no special care is needed by the SIGCHLD handler. - */ -} - |