X-Git-Url: https://git.distorted.org.uk/~mdw/fwd/blobdiff_plain/fc170a33ade808c25d6a7dee7dd00aba290477c3..d1c182e7ea23547f2da0f621248fae25b8080af9:/fw.c diff --git a/fw.c b/fw.c index 68871a6..3d3f336 100644 --- a/fw.c +++ b/fw.c @@ -1,6 +1,6 @@ /* -*-c-*- * - * $Id: fw.c,v 1.7 2000/03/23 00:37:33 mdw Exp $ + * $Id: fw.c,v 1.11 2001/02/03 20:33:26 mdw Exp $ * * Port forwarding thingy * @@ -29,6 +29,18 @@ /*----- Revision history --------------------------------------------------* * * $Log: fw.c,v $ + * Revision 1.11 2001/02/03 20:33:26 mdw + * Fix flags to be unsigned. + * + * Revision 1.10 2001/02/03 20:30:03 mdw + * Support re-reading config files on SIGHUP. + * + * Revision 1.9 2001/01/20 11:55:17 mdw + * Handle select errors more robustly. + * + * Revision 1.8 2000/03/23 23:19:19 mdw + * Fix changed options in parser table. + * * Revision 1.7 2000/03/23 00:37:33 mdw * Add option to change user and group after initialization. Naughtily * reassign short equivalents of --grammar and --options. @@ -59,6 +71,7 @@ #include "config.h" +#include #include #include #include @@ -97,8 +110,14 @@ sel_state *sel; /* Multiplexor for nonblocking I/O */ /*----- Static variables --------------------------------------------------*/ +typedef struct conffile { + struct conffile *next; + char *name; +} conffile; + static unsigned flags = 0; /* Global state flags */ static unsigned active = 0; /* Number of active things */ +static conffile *conffiles = 0; /* List of configuration files */ #define FW_SYSLOG 1u #define FW_QUIET 2u @@ -183,14 +202,72 @@ static void fw_exit(void) static void fw_tidy(int n, void *p) { - const char *sn = "unexpected signal (bug!)"; - if (n == SIGTERM) - sn = "SIGTERM"; - else if (n == SIGINT) - sn = "SIGINT"; - - fw_log(-1, "closing down on %s", sn); - fw_exit(); + const char *sn = 0; + switch (n) { + case SIGTERM: sn = "SIGTERM"; break; + case SIGINT: sn = "SIGINT"; break; + default: abort(); + } + + fw_log(-1, "closing down gracefully on %s", sn); + source_killall(); +} + +/* --- @fw_die@ --- * + * + * Arguments: @int n@ = signal number + * @void *p@ = an uninteresting argument + * + * Returns: --- + * + * Use: Handles various signals and causes an abrupt shutdown. + */ + +static void fw_die(int n, void *p) +{ + const char *sn = 0; + switch (n) { + case SIGQUIT: sn = "SIGQUIT"; break; + default: abort(); + } + + fw_log(-1, "closing down abruptly on %s", sn); + source_killall(); + endpt_killall(); +} + +/* --- @fw_reload@ --- * + * + * Arguments: @int n@ = a signal number + * @void *p@ = an uninteresting argument + * + * Returns: --- + * + * Use: Handles a hangup signal by re-reading configuration files. + */ + +static void fw_reload(int n, void *p) +{ + FILE *fp; + scanner sc; + conffile *cf; + + assert(n == SIGHUP); + if (!conffiles) { + fw_log(-1, "no configuration files to reload: ignoring SIGHUP"); + return; + } + fw_log(-1, "reloading configuration files..."); + source_killall(); + scan_create(&sc); + for (cf = conffiles; cf; cf = cf->next) { + if ((fp = fopen(cf->name, "r")) == 0) + fw_log(-1, "error loading `%s': %s", cf->name, strerror(errno)); + else + scan_add(&sc, scan_file(fp, cf->name, 0)); + } + conf_parse(&sc); + fw_log(-1, "... reload completed OK"); } /* --- Standard GNU help options --- */ @@ -351,17 +428,16 @@ int main(int argc, char *argv[]) { unsigned f = 0; sel_state sst; - sig s_term, s_int; + sig s_term, s_quit, s_int, s_hup; scanner sc; uid_t drop = -1; gid_t dropg = -1; + conffile *cf, **cff = &conffiles; - enum { - f_bogus = 1, - f_file = 2, - f_syslog = 4, - f_fork = 8 - }; +#define f_bogus 1u +#define f_file 2u +#define f_syslog 4u +#define f_fork 8u /* --- Initialize things --- */ @@ -376,20 +452,6 @@ int main(int argc, char *argv[]) fattr_init(&fattr_global); scan_create(&sc); - /* --- Set up some signal handlers --- * - * - * Don't enable @SIGINT@ if the caller already disabled it. - */ - - { - struct sigaction sa; - - sig_add(&s_term, SIGTERM, fw_tidy, 0); - sigaction(SIGINT, 0, &sa); - if (sa.sa_handler != SIG_IGN) - sig_add(&s_int, SIGINT, fw_tidy, 0); - } - atexit(fw_exit); /* --- Parse command line options --- */ @@ -405,8 +467,8 @@ int main(int argc, char *argv[]) /* --- Other help options --- */ - { "grammar", 0, 0, 'g' }, - { "options", 0, 0, 'o' }, + { "grammar", 0, 0, 'G' }, + { "options", 0, 0, 'O' }, /* --- Other useful arguments --- */ @@ -457,6 +519,10 @@ int main(int argc, char *argv[]) FILE *fp; if ((fp = fopen(optarg, "r")) == 0) die(1, "couldn't open file `%s': %s", optarg, strerror(errno)); + cf = CREATE(conffile); + cf->name = optarg; + *cff = cf; + cff = &cf->next; scan_add(&sc, scan_file(fp, optarg, 0)); } f |= f_file; @@ -506,6 +572,7 @@ int main(int argc, char *argv[]) usage(stderr); exit(1); } + *cff = 0; /* --- Deal with the remaining arguments --- */ @@ -525,15 +592,33 @@ int main(int argc, char *argv[]) conf_parse(&sc); + /* --- Set up some signal handlers --- * + * + * Don't enable @SIGINT@ if the caller already disabled it. + */ + + { + struct sigaction sa; + + sig_add(&s_term, SIGTERM, fw_tidy, 0); + sig_add(&s_quit, SIGQUIT, fw_die, 0); + sigaction(SIGINT, 0, &sa); + if (sa.sa_handler != SIG_IGN) + sig_add(&s_int, SIGINT, fw_tidy, 0); + sig_add(&s_hup, SIGHUP, fw_reload, 0); + } + /* --- Drop privileges --- */ #ifdef HAVE_SETGROUPS if ((dropg != -1 && (setgid(dropg) || setgroups(1, &dropg))) || + (drop != -1 && setuid(drop))) + die(1, "couldn't drop privileges: %s", strerror(errno)); #else if ((dropg != -1 && setgid(dropg)) || -#endif (drop != -1 && setuid(drop))) die(1, "couldn't drop privileges: %s", strerror(errno)); +#endif /* --- Fork into the background --- */ @@ -565,8 +650,23 @@ int main(int argc, char *argv[]) if (!(flags & FW_SET)) moan("nothing to do!"); signal(SIGPIPE, SIG_IGN); - while (active) - sel_select(sel); + + { + int selerr = 0; + while (active) { + if (!sel_select(sel)) + selerr = 0; + else if (errno != EINTR && errno != EAGAIN) { + fw_log(-1, "error from select: %s", strerror(errno)); + selerr++; + if (selerr > 8) { + fw_log(-1, "too many consecutive select errors: bailing out"); + exit(EXIT_FAILURE); + } + } + } + } + return (0); }