diff options
Diffstat (limited to 'release/src/router/busybox/networking/nc.c')
| -rw-r--r-- | release/src/router/busybox/networking/nc.c | 288 |
1 files changed, 156 insertions, 132 deletions
diff --git a/release/src/router/busybox/networking/nc.c b/release/src/router/busybox/networking/nc.c index 4888ccce..fe845f58 100644 --- a/release/src/router/busybox/networking/nc.c +++ b/release/src/router/busybox/networking/nc.c @@ -1,147 +1,171 @@ /* vi: set sw=4 ts=4: */ /* nc: mini-netcat - built from the ground up for LRP - Copyright (C) 1998 Charles P. Wright + * + * Copyright (C) 1998, 1999 Charles P. Wright + * Copyright (C) 1998 Dave Cinege + * + * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. + */ - 0.0.1 6K It works. - 0.0.2 5K Smaller and you can also check the exit condition if you wish. - 0.0.3 Uses select() +#include "libbb.h" - 19980918 Busy Boxed! Dave Cinege - 19990512 Uses Select. Charles P. Wright - 19990513 Fixes stdin stupidity and uses buffers. Charles P. Wright +#if ENABLE_DESKTOP +#include "nc_bloaty.c" +#else - 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. +/* Lots of small differences in features + * when compared to "standard" nc + */ - This program is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. - - You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. - -*/ - -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <unistd.h> - -#include <sys/types.h> -#include <sys/socket.h> -#include <netinet/in.h> -#include <arpa/inet.h> -#include <netdb.h> -#include <sys/time.h> -#include <sys/ioctl.h> -#include "busybox.h" - -#define GAPING_SECURITY_HOLE +static void timeout(int signum UNUSED_PARAM) +{ + bb_error_msg_and_die("timed out"); +} +int nc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int nc_main(int argc, char **argv) { - int do_listen = 0, lport = 0, delay = 0, tmpfd, opt, sfd, x; - char buf[BUFSIZ]; -#ifdef GAPING_SECURITY_HOLE - char * pr00gie = NULL; -#endif - - struct sockaddr_in address; - struct hostent *hostinfo; - + /* sfd sits _here_ only because of "repeat" option (-l -l). */ + int sfd = sfd; /* for gcc */ + int cfd = 0; + unsigned lport = 0; + SKIP_NC_SERVER(const) unsigned do_listen = 0; + SKIP_NC_EXTRA (const) unsigned wsecs = 0; + SKIP_NC_EXTRA (const) unsigned delay = 0; + SKIP_NC_EXTRA (const int execparam = 0;) + USE_NC_EXTRA (char **execparam = NULL;) + len_and_sockaddr *lsa; fd_set readfds, testfds; - - while ((opt = getopt(argc, argv, "lp:i:e:")) > 0) { - switch (opt) { - case 'l': - do_listen++; - break; - case 'p': - lport = atoi(optarg); - break; - case 'i': - delay = atoi(optarg); - break; -#ifdef GAPING_SECURITY_HOLE - case 'e': - pr00gie = optarg; - break; -#endif - default: - bb_show_usage(); + int opt; /* must be signed (getopt returns -1) */ + + if (ENABLE_NC_SERVER || ENABLE_NC_EXTRA) { + /* getopt32 is _almost_ usable: + ** it cannot handle "... -e prog -prog-opt" */ + while ((opt = getopt(argc, argv, + "" USE_NC_SERVER("lp:") USE_NC_EXTRA("w:i:f:e:") )) > 0 + ) { + if (ENABLE_NC_SERVER && opt=='l') + USE_NC_SERVER(do_listen++); + else if (ENABLE_NC_SERVER && opt=='p') + USE_NC_SERVER(lport = bb_lookup_port(optarg, "tcp", 0)); + else if (ENABLE_NC_EXTRA && opt=='w') + USE_NC_EXTRA( wsecs = xatou(optarg)); + else if (ENABLE_NC_EXTRA && opt=='i') + USE_NC_EXTRA( delay = xatou(optarg)); + else if (ENABLE_NC_EXTRA && opt=='f') + USE_NC_EXTRA( cfd = xopen(optarg, O_RDWR)); + else if (ENABLE_NC_EXTRA && opt=='e' && optind <= argc) { + /* We cannot just 'break'. We should let getopt finish. + ** Or else we won't be able to find where + ** 'host' and 'port' params are + ** (think "nc -w 60 host port -e prog"). */ + USE_NC_EXTRA( + char **p; + // +2: one for progname (optarg) and one for NULL + execparam = xzalloc(sizeof(char*) * (argc - optind + 2)); + p = execparam; + *p++ = optarg; + while (optind < argc) { + *p++ = argv[optind++]; + } + ) + /* optind points to argv[arvc] (NULL) now. + ** FIXME: we assume that getopt will not count options + ** possibly present on "-e prog args" and will not + ** include them into final value of optind + ** which is to be used ... */ + } else bb_show_usage(); } + argv += optind; /* ... here! */ + argc -= optind; + // -l and -f don't mix + if (do_listen && cfd) bb_show_usage(); + // Listen or file modes need zero arguments, client mode needs 2 + if (do_listen || cfd) { + if (argc) bb_show_usage(); + } else { + if (!argc || argc > 2) bb_show_usage(); + } + } else { + if (argc != 3) bb_show_usage(); + argc--; + argv++; } -#ifdef GAPING_SECURITY_HOLE - if (pr00gie) { - /* won't need stdin */ - close (fileno(stdin)); + if (wsecs) { + signal(SIGALRM, timeout); + alarm(wsecs); } -#endif /* GAPING_SECURITY_HOLE */ - - - if ((do_listen && optind != argc) || (!do_listen && optind + 2 != argc)) - bb_show_usage(); - if ((sfd = socket(AF_INET, SOCK_STREAM, 0)) < 0) - bb_perror_msg_and_die("socket"); - x = 1; - if (setsockopt (sfd, SOL_SOCKET, SO_REUSEADDR, &x, sizeof (x)) == -1) - bb_perror_msg_and_die ("reuseaddr failed"); - address.sin_family = AF_INET; - - if (lport != 0) { - memset(&address.sin_addr, 0, sizeof(address.sin_addr)); - address.sin_port = htons(lport); - - if (bind(sfd, (struct sockaddr *) &address, sizeof(address)) < 0) - bb_perror_msg_and_die("bind"); + if (!cfd) { + if (do_listen) { + /* create_and_bind_stream_or_die(NULL, lport) + * would've work wonderfully, but we need + * to know lsa */ + sfd = xsocket_stream(&lsa); + if (lport) + set_nport(lsa, htons(lport)); + setsockopt_reuseaddr(sfd); + xbind(sfd, &lsa->u.sa, lsa->len); + xlisten(sfd, do_listen); /* can be > 1 */ + /* If we didn't specify a port number, + * query and print it after listen() */ + if (!lport) { + socklen_t addrlen = lsa->len; + getsockname(sfd, &lsa->u.sa, &addrlen); + lport = get_nport(&lsa->u.sa); + fdprintf(2, "%d\n", ntohs(lport)); + } + close_on_exec_on(sfd); + accept_again: + cfd = accept(sfd, NULL, 0); + if (cfd < 0) + bb_perror_msg_and_die("accept"); + if (!execparam) + close(sfd); + } else { + cfd = create_and_connect_stream_or_die(argv[0], + argv[1] ? bb_lookup_port(argv[1], "tcp", 0) : 0); + } } - if (do_listen) { - socklen_t addrlen = sizeof(address); - - if (listen(sfd, 1) < 0) - bb_perror_msg_and_die("listen"); - - if ((tmpfd = accept(sfd, (struct sockaddr *) &address, &addrlen)) < 0) - bb_perror_msg_and_die("accept"); - - close(sfd); - sfd = tmpfd; - } else { - hostinfo = xgethostbyname(argv[optind]); - - address.sin_addr = *(struct in_addr *) *hostinfo->h_addr_list; - address.sin_port = htons(atoi(argv[optind+1])); - - if (connect(sfd, (struct sockaddr *) &address, sizeof(address)) < 0) - bb_perror_msg_and_die("connect"); + if (wsecs) { + alarm(0); + /* Non-ignored siganls revert to SIG_DFL on exec anyway */ + /*signal(SIGALRM, SIG_DFL);*/ } -#ifdef GAPING_SECURITY_HOLE /* -e given? */ - if (pr00gie) { - dup2(sfd, 0); - close(sfd); - dup2 (0, 1); - dup2 (0, 2); - execl (pr00gie, pr00gie, NULL); + if (execparam) { + signal(SIGCHLD, SIG_IGN); + // With more than one -l, repeatedly act as server. + if (do_listen > 1 && vfork()) { + /* parent */ + // This is a bit weird as cleanup goes, since we wind up with no + // stdin/stdout/stderr. But it's small and shouldn't hurt anything. + // We check for cfd == 0 above. + logmode = LOGMODE_NONE; + close(0); + close(1); + close(2); + goto accept_again; + } + /* child (or main thread if no multiple -l) */ + xmove_fd(cfd, 0); + xdup2(0, 1); + xdup2(0, 2); + USE_NC_EXTRA(BB_EXECVP(execparam[0], execparam);) /* Don't print stuff or it will go over the wire.... */ - _exit(-1); + _exit(127); } -#endif /* GAPING_SECURITY_HOLE */ + // Select loop copying stdin to cfd, and cfd to stdout. FD_ZERO(&readfds); - FD_SET(sfd, &readfds); + FD_SET(cfd, &readfds); FD_SET(STDIN_FILENO, &readfds); - while (1) { + for (;;) { int fd; int ofd; int nread; @@ -151,27 +175,27 @@ int nc_main(int argc, char **argv) if (select(FD_SETSIZE, &testfds, NULL, NULL, NULL) < 0) bb_perror_msg_and_die("select"); +#define iobuf bb_common_bufsiz1 for (fd = 0; fd < FD_SETSIZE; fd++) { if (FD_ISSET(fd, &testfds)) { - if ((nread = safe_read(fd, buf, sizeof(buf))) < 0) - bb_perror_msg_and_die("read"); - - if (fd == sfd) { - if (nread == 0) - exit(0); + nread = safe_read(fd, iobuf, sizeof(iobuf)); + if (fd == cfd) { + if (nread < 1) + exit(EXIT_SUCCESS); ofd = STDOUT_FILENO; } else { - if (nread == 0) - shutdown(sfd, 1); - ofd = sfd; - } - - if (bb_full_write(ofd, buf, nread) < 0) - bb_perror_msg_and_die("write"); - if (delay > 0) { - sleep(delay); + if (nread<1) { + // Close outgoing half-connection so they get EOF, but + // leave incoming alone so we can see response. + shutdown(cfd, 1); + FD_CLR(STDIN_FILENO, &readfds); + } + ofd = cfd; } + xwrite(ofd, iobuf, nread); + if (delay > 0) sleep(delay); } } } } +#endif |