X-Git-Url: https://git.distorted.org.uk/~mdw/fwd/blobdiff_plain/7481fc9c5a603e35a6972c0be07d18d507e5dd50..a9bd543ab4ebe415bca9d6f27b90f16ddac79bc0:/fw.c diff --git a/fw.c b/fw.c index 59bc18f..4b0a861 100644 --- a/fw.c +++ b/fw.c @@ -1,13 +1,11 @@ /* -*-c-*- * - * $Id: fw.c,v 1.17 2004/04/08 01:36:25 mdw Exp $ - * * Port forwarding thingy * * (c) 1999 Straylight/Edgeware */ -/*----- Licensing notice --------------------------------------------------* +/*----- Licensing notice --------------------------------------------------* * * This file is part of the `fw' port forwarder. * @@ -15,56 +13,18 @@ * 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. - * + * * `fw' 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 `fw'; if not, write to the Free Software Foundation, * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ -/*----- Header files ------------------------------------------------------*/ - -#include "config.h" - -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include -#include - -#include -#include - -#include -#include -#include -#include -#include -#include -#include -#include - -#include "conf.h" -#include "endpt.h" -#include "exec.h" -#include "fattr.h" -#include "file.h" #include "fw.h" -#include "privconn.h" -#include "scan.h" -#include "socket.h" -#include "source.h" /*----- Global variables --------------------------------------------------*/ @@ -115,7 +75,7 @@ void parse(scanner *sc) if (strcmp(sc->d.buf, "forward") == 0 || strcmp(sc->d.buf, "fw") == 0 || - strcmp(sc->d.buf, "from") == 0) { + strcmp(sc->d.buf, "from") == 0) { source *s; target *t; @@ -417,7 +377,7 @@ static void version(FILE *fp) static void usage(FILE *fp) { - pquis(fp, "Usage: $ [-dql] [-f file] [config statements...]\n"); + pquis(fp, "Usage: $ [-dql] [-p PIDFILE] [-f FILE] [CONFIG-STMTS...]\n"); } static void help(FILE *fp) @@ -427,22 +387,7 @@ static void help(FILE *fp) usage(fp); pquis(fp, "\n\ An excessively full-featured port-forwarder, which subsumes large chunks\n\ -of the functionality of inetd, netcat, and normal cat. Options available\n\ -are:\n\ -\n\ --h, --help Display this help message.\n\ --v, --version Display the program's version number.\n\ --u, --usage Display a terse usage summary.\n\ -\n\ --G, --grammar Show a summary of the configuration language.\n\ --O, --options Show a summary of the source and target options.\n\ -\n\ --f, --file=FILE Read configuration from a file.\n\ --q, --quiet Don't emit any logging information.\n\ --d, --daemon Fork into background after initializing.\n\ --l, --syslog Send log output to the system logger.\n\ --s, --setuid=USER Change uid to USER after initializing sources.\n\ --g, --setgid=GRP Change gid to GRP after initializing sources.\n\ +of the functionality of inetd, netcat, and normal cat.\n\ \n\ Configuration may be supplied in one or more configuration files, or on\n\ the command line (or both). If no `-f' option is present, and no\n\ @@ -455,6 +400,26 @@ to be a separate line.\n\ \n\ The grammar is fairly complicated. For a summary, run `$ --grammar'.\n\ For a summary of the various options, run `$ --options'.\n\ +\n\ +Options available are:\n\ +\n\ +Help options:\n\ + -h, --help Display this help message.\n\ + -v, --version Display the program's version number.\n\ + -u, --usage Display a terse usage summary.\n\ +\n\ +Configuration summary:\n\ + -G, --grammar Show a summary of the configuration language.\n\ + -O, --options Show a summary of the source and target options.\n\ +\n\ +Other options:\n\ + -f, --file=FILE Read configuration from a file.\n\ + -q, --quiet Don't emit any logging information.\n\ + -d, --daemon Fork into background after initializing.\n\ + -p, --pidfile=FILE Write process-id to the named FILE.\n\ + -l, --syslog Send log output to the system logger.\n\ + -s, --setuid=USER Change uid to USER after initializing sources.\n\ + -g, --setgid=GRP Change gid to GRP after initializing sources.\n\ "); } @@ -463,100 +428,15 @@ For a summary of the various options, run `$ --options'.\n\ static void grammar(FILE *fp) { version(fp); - pquis(fp, "\n\ -Grammar summary\n\ -\n\ -Basic syntax\n\ - FILE ::= EMPTY | FILE STMT [`;']\n\ - STMT ::= OPTION-STMT | FW-STMT\n\ - FW-STMT ::= `fw' SOURCE OPTIONS [`to'|`->'] TARGET OPTIONS\n\ - OPTIONS ::= `{' OPTION-SEQ `}'\n\ - OPTION-SEQ ::= EMPTY | OPTION-STMT [`;'] OPTION-SEQ\n\ -\n\ -Option syntax\n\ - OPTION-STMT ::= Q-OPTION\n\ - Q-OPTION ::= OPTION\n\ - | PREFIX `.' Q-OPTION\n\ - | PREFIX `{' OPTION-SEQ `}'\n\ - PREFIX ::= WORD\n\ -\n\ -File source and target\n\ - SOURCE ::= FILE\n\ - TARGET ::= FILE\n\ - FILE ::= `file' [`.'] FSPEC [`,' FSPEC]\n\ - FSPEC ::= FD-SPEC | NAME-SPEC | NULL-SPEC\n\ - FD-SPEC ::= [[`:']`fd'[`:']] NUMBER|`stdin'|`stdout'\n\ - NAME-SPEC ::= [[`:']`file'[`:']] FILE-NAME\n\ - FILE-NAME ::= PATH-SEQ | [ PATH-SEQ ]\n\ - PATH-SEQ ::= PATH-ELT | PATH-SEQ PATH-ELT\n\ - PATH-ELT ::= `/' | WORD\n\ - NULL-SPEC ::= [`:']`null'[`:']\n\ -\n\ -Exec source and target\n\ - SOURCE ::= EXEC\n\ - TARGET ::= EXEC\n\ - EXEC ::= `exec' [`.'] CMD-SPEC\n\ - CMD-SPEC ::= SHELL-CMD | [PROG-NAME] `[' ARGV0 ARG-SEQ `]'\n\ - ARG-SEQ ::= WORD | ARG-SEQ WORD\n\ - SHELL-CMD ::= WORD\n\ - ARGV0 ::= WORD\n\ -\n\ -Socket source and target\n\ - SOURCE ::= SOCKET-SOURCE\n\ - TARGET ::= SOCKET-TARGET\n\ - SOCKET-SOURCE ::= [`socket'[`.']] [[`:']ADDR-TYPE[`:']] SOURCE-ADDR\n\ - SOCKET-TARGET ::= [`socket'[`.']] [[`:']ADDR-TYPE[`:']] TARGET-ADDR\n\ -\n\ - INET-SOURCE-ADDR ::= [`port'] PORT\n\ - INET-TARGET-ADDR ::= ADDRESS [`:'] PORT\n\ - ADDRESS ::= ADDR-ELT | ADDRESS ADDR-ELT\n\ - ADDR-ELT ::= `.' | WORD\n\ -\n\ - UNIX-SOURCE-ADDR ::= FILE-NAME\n\ - UNIX-TARGET-ADDR ::= FILE-NAME\n\ -"); + fputs("\nGrammar summary\n\n", fp); + fputs(grammar_text, fp); } static void options(FILE *fp) { version(fp); - pquis(fp, "\n\ -Options summary\n\ -\n\ -File attributes (`fattr')\n\ - prefix.FATTR.MODE [=] MODE\n\ - prefix.FATTR.OWNER [=] USER\n\ - prefix.FATTR.GROUP [=] GROUP\n\ -\n\ -File options\n\ - file.create [=] yes|no\n\ - file.open [=] no|truncate|append\n\ - file.fattr.*\n\ -\n\ -Exec options\n\ - exec.logging [=] yes|no\n\ - exec.dir [=] FILE-NAME\n\ - exec.root [=] FILE-NAME\n\ - exec.user [=] USER\n\ - exec.group [=] GROUP\n\ - exec.rlimit.LIMIT[.hard|.soft] [=] VALUE\n\ - exec.env.clear\n\ - exec.env.unset VAR\n\ - exec.env.[set] VAR [=] VALUE\n\ -\n\ -Socket options\n\ - socket.conn [=] NUMBER|unlimited|one-shot\n\ - socket.listen [=] NUMBER\n\ - socket.logging [=] yes|no\n\ -\n\ - socket.inet.source.[allow|deny] [host] ADDR [/ ADDR]\n\ - socket.inet.source.[allow|deny] priv-port\n\ - socket.inet.source.addr [=] any|ADDR\n\ - socket.inet.dest.addr [=] any|ADDR\n\ - socket.inet.dest.priv-port [=] yes|no\n\ -\n\ - socket.unix.fattr.*\n\ -"); + fputs("\nOption summary\n\n", fp); + fputs(option_text, fp); } /* --- @main@ --- * @@ -577,6 +457,7 @@ int main(int argc, char *argv[]) scanner sc; uid_t drop = -1; gid_t dropg = -1; + const char *pidfile = 0; conffile *cf, **cff = &conffiles; #define f_bogus 1u @@ -620,6 +501,7 @@ int main(int argc, char *argv[]) { "file", OPTF_ARGREQ, 0, 'f' }, { "fork", 0, 0, 'd' }, { "daemon", 0, 0, 'd' }, + { "pidfile", OPTF_ARGREQ, 0, 'p' }, { "syslog", 0, 0, 'l' }, { "log", 0, 0, 'l' }, { "quiet", 0, 0, 'q' }, @@ -632,7 +514,7 @@ int main(int argc, char *argv[]) { 0, 0, 0, 0 } }; - int i = mdwopt(argc, argv, "+hvu GO f:dls:g:", opts, 0, 0, 0); + int i = mdwopt(argc, argv, "+hvu" "GO" "f:dp:ls:g:", opts, 0, 0, 0); if (i < 0) break; @@ -675,6 +557,9 @@ int main(int argc, char *argv[]) case 'd': f |= f_fork; break; + case 'p': + pidfile = optarg; + break; case 'l': f |= f_syslog; break; @@ -682,7 +567,7 @@ int main(int argc, char *argv[]) flags |= FW_QUIET; break; case 's': - if (isdigit((unsigned char )optarg[0])) { + if (isdigit((unsigned char )optarg[0])) { char *q; drop = strtol(optarg, &q, 0); if (*q) @@ -695,7 +580,7 @@ int main(int argc, char *argv[]) } break; case 'g': - if (isdigit((unsigned char )optarg[0])) { + if (isdigit((unsigned char )optarg[0])) { char *q; dropg = strtol(optarg, &q, 0); if (*q) @@ -753,20 +638,6 @@ int main(int argc, char *argv[]) sig_add(&s_hup, SIGHUP, fw_reload, 0); } - /* --- Drop privileges --- */ - - if (drop != (uid_t)-1) - privconn_split(sel); -#ifdef HAVE_SETGROUPS - if ((dropg != (gid_t)-1 && (setgid(dropg) || setgroups(1, &dropg))) || - (drop != (uid_t)-1 && setuid(drop))) - die(1, "couldn't drop privileges: %s", strerror(errno)); -#else - if ((dropg != (gid_t)-1 && setgid(dropg)) || - (drop != (uid_t)-1 && setuid(drop))) - die(1, "couldn't drop privileges: %s", strerror(errno)); -#endif - /* --- Fork into the background --- */ if (f & f_fork) { @@ -786,12 +657,38 @@ int main(int argc, char *argv[]) if (kid != 0) _exit(0); } + if (pidfile) { + FILE *fp = fopen(pidfile, "w"); + if (!fp) { + die(EXIT_FAILURE, "couldn't create pidfile `%s': %s", + pidfile, strerror(errno)); + } + fprintf(fp, "%lu\n", (unsigned long)getpid()); + if (fflush(fp) || ferror(fp) || fclose(fp)) { + die(EXIT_FAILURE, "couldn't write pidfile `%s': %s", + pidfile, strerror(errno)); + } + } if (f & f_syslog) { flags |= FW_SYSLOG; openlog(QUIS, 0, LOG_DAEMON); } + /* --- Drop privileges --- */ + + if (drop != (uid_t)-1) + privconn_split(sel); +#ifdef HAVE_SETGROUPS + if ((dropg != (gid_t)-1 && (setgid(dropg) || setgroups(1, &dropg))) || + (drop != (uid_t)-1 && setuid(drop))) + die(1, "couldn't drop privileges: %s", strerror(errno)); +#else + if ((dropg != (gid_t)-1 && setgid(dropg)) || + (drop != (uid_t)-1 && setuid(drop))) + die(1, "couldn't drop privileges: %s", strerror(errno)); +#endif + /* --- Let rip --- */ if (!(flags & FW_SET)) @@ -802,7 +699,7 @@ int main(int argc, char *argv[]) int selerr = 0; while (active) { if (!sel_select(sel)) - selerr = 0; + selerr = 0; else if (errno != EINTR && errno != EAGAIN) { fw_log(-1, "error from select: %s", strerror(errno)); selerr++; @@ -813,7 +710,7 @@ int main(int argc, char *argv[]) } } } - + return (0); }