X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?p=secnet.git;a=blobdiff_plain;f=secnet.c;h=111a1b0886f0c1e11a0d8a367a6aec75136689f9;hp=c7ce2b8a459b6707431b11e2bd182e637035a6c1;hb=f1393100aa5412f0df5ee363c6bdd42b2465fa59;hpb=7138d0c54cd2212439434d27cb2d6ea775c3039b diff --git a/secnet.c b/secnet.c index c7ce2b8..111a1b0 100644 --- a/secnet.c +++ b/secnet.c @@ -1,13 +1,7 @@ -/* $Log: secnet.c,v $ - * Revision 1.1 1996/03/13 22:27:41 sde1000 - * Initial revision - * - */ - -extern char version[]; - #include "secnet.h" #include +#include +#include #include #include #include @@ -15,43 +9,46 @@ extern char version[]; #include #include #include +#include #include "util.h" #include "conffile.h" #include "process.h" +#if __APPLE__ +/* apple's poll() does not work on char devs */ +# define USE_SELECT 1 +#endif + /* XXX should be from autoconf */ -static char *configfile="/etc/secnet/secnet.conf"; +static const char *configfile="/etc/secnet/secnet.conf"; +static const char *sites_key="sites"; bool_t just_check_config=False; static char *userid=NULL; static uid_t uid=0; +static gid_t gid; bool_t background=True; static char *pidfile=NULL; bool_t require_root_privileges=False; -string_t require_root_privileges_explanation=NULL; +cstring_t require_root_privileges_explanation=NULL; static pid_t secnet_pid; -/* from log.c */ -extern uint32_t message_level; -extern bool_t secnet_is_daemon; -extern struct log_if *system_log; - -/* from process.c */ -extern void start_signal_handling(void); - /* Structures dealing with poll() call */ struct poll_interest { - beforepoll_fn *before; + beforepoll_fn *before; /* 0 if deregistered and waiting to be deleted */ afterpoll_fn *after; void *state; - uint32_t max_nfds; - uint32_t nfds; - string_t desc; - struct poll_interest *next; + int32_t nfds; + cstring_t desc; + LIST_ENTRY(poll_interest) entry; }; -static struct poll_interest *reg=NULL; -static uint32_t total_nfds=10; +static LIST_HEAD(, poll_interest) reg = LIST_HEAD_INITIALIZER(®); + +static bool_t interest_isregistered(const struct poll_interest *i) +{ + return !!i->before; +} static bool_t finished=False; @@ -68,15 +65,17 @@ static void parse_options(int argc, char **argv) {"help", 0, 0, 2}, {"version", 0, 0, 1}, {"nodetach", 0, 0, 'n'}, + {"managed", 0, 0, 'm'}, {"silent", 0, 0, 'f'}, {"quiet", 0, 0, 'f'}, - {"debug", 1, 0, 'd'}, + {"debug", 0, 0, 'd'}, {"config", 1, 0, 'c'}, {"just-check-config", 0, 0, 'j'}, + {"sites-key", 1, 0, 's'}, {0,0,0,0} }; - c=getopt_long(argc, argv, "vwdnjc:ft:", + c=getopt_long(argc, argv, "vwdnjc:ft:s:m", long_options, &option_index); if (c==-1) break; @@ -84,29 +83,33 @@ static void parse_options(int argc, char **argv) switch(c) { case 2: /* Help */ - fprintf(stderr, - "Usage: secnet [OPTION]...\n\n" - " -f, --silent, --quiet suppress error messages\n" - " -w, --nowarnings suppress warnings\n" - " -v, --verbose output extra diagnostics\n" - " -c, --config=filename specify a configuration file\n" - " -j, --just-check-config stop after reading configfile\n" - " -n, --nodetach do not run in background\n" - " -d, --debug=item,... set debug options\n" - " --help display this help and exit\n" - " --version output version information and exit\n" + printf("Usage: secnet [OPTION]...\n\n" + " -f, --silent, --quiet suppress error messages\n" + " -w, --nowarnings suppress warnings\n" + " -v, --verbose output extra diagnostics\n" + " -c, --config=filename specify a configuration file\n" + " -j, --just-check-config stop after reading " + "configuration file\n" + " -s, --sites-key=name configuration key that " + "specifies active sites\n" + " -n, --nodetach do not run in background\n" + " -m, --managed running under a supervisor\n" + " -d, --debug output debug messages\n" + " --help display this help and exit\n" + " --version output version information " + "and exit\n" ); exit(0); break; case 1: /* Version */ - fprintf(stderr,"%s\n",version); + printf("%s\n",version); exit(0); break; case 'v': - message_level|=M_INFO|M_NOTICE|M_WARNING|M_ERROR|M_SECURITY| + message_level|=M_INFO|M_NOTICE|M_WARNING|M_ERR|M_SECURITY| M_FATAL; break; @@ -126,6 +129,10 @@ static void parse_options(int argc, char **argv) background=False; break; + case 'm': + secnet_is_daemon=True; + break; + case 'c': if (optarg) configfile=safe_strdup(optarg,"config_filename"); @@ -137,16 +144,24 @@ static void parse_options(int argc, char **argv) just_check_config=True; break; + case 's': + if (optarg) + sites_key=safe_strdup(optarg,"sites-key"); + else + fatal("secnet: no sites key specified"); + break; + case '?': + exit(1); break; default: - Message(M_ERROR,"secnet: Unknown getopt code %c\n",c); + Message(M_ERR,"secnet: Unknown getopt code %c\n",c); } } if (argc-optind != 0) { - Message(M_ERROR,"secnet: You gave extra command line parameters, " + Message(M_ERR,"secnet: You gave extra command line parameters, " "which were ignored.\n"); } } @@ -163,7 +178,7 @@ static void setup(dict_t *config) l=dict_lookup(config,"system"); if (!l || list_elem(l,0)->type!=t_dict) { - fatal("configuration does not include a \"system\" dictionary\n"); + fatal("configuration does not include a \"system\" dictionary"); } system=list_elem(l,0)->data.dict; loc=list_elem(l,0)->loc; @@ -171,24 +186,17 @@ static void setup(dict_t *config) /* Arrange systemwide log facility */ l=dict_lookup(system,"log"); if (!l) { - fatal("configuration does not include a system/log facility\n"); + fatal("configuration does not include a system/log facility"); } system_log=init_log(l); /* Who are we supposed to run as? */ userid=dict_read_string(system,"userid",False,"system",loc); if (userid) { - do { - pw=getpwent(); - if (pw && strcmp(pw->pw_name,userid)==0) { - uid=pw->pw_uid; - break; - } - } while(pw); - endpwent(); - if (uid==0) { - fatal("userid \"%s\" not found\n",userid); - } + if (!(pw=getpwnam(userid))) + fatal("userid \"%s\" not found",userid); + uid=pw->pw_uid; + gid=pw->pw_gid; } /* Pidfile name */ @@ -196,16 +204,16 @@ static void setup(dict_t *config) /* Check whether we need root privileges */ if (require_root_privileges && uid!=0) { - fatal("the following configured feature (\"%s\") requires " - "that secnet retain root privileges while running.\n", + fatal("the configured feature \"%s\" requires " + "that secnet retain root privileges while running.", require_root_privileges_explanation); } /* Go along site list, starting sites */ - l=dict_lookup(config,"sites"); + l=dict_lookup(config,sites_key); if (!l) { - Message(M_WARNING,"secnet: configuration did not define any " - "remote sites\n"); + Message(M_WARNING,"secnet: configuration key \"%s\" is missing; no " + "remote sites are defined\n",sites_key); } else { i=0; while ((site=list_elem(l, i++))) { @@ -222,8 +230,8 @@ static void setup(dict_t *config) } } -void register_for_poll(void *st, beforepoll_fn *before, - afterpoll_fn *after, uint32_t max_nfds, string_t desc) +struct poll_interest *register_for_poll(void *st, beforepoll_fn *before, + afterpoll_fn *after, cstring_t desc) { struct poll_interest *i; @@ -231,13 +239,18 @@ void register_for_poll(void *st, beforepoll_fn *before, i->before=before; i->after=after; i->state=st; - i->max_nfds=max_nfds; i->nfds=0; i->desc=desc; - total_nfds+=max_nfds; - i->next=reg; - reg=i; - return; + LIST_INSERT_HEAD(®, i, entry); + return i; +} + +void deregister_for_poll(struct poll_interest *i) +{ + /* We cannot simply throw this away because we're reentrantly + * inside the main loop, which needs to remember which range of + * fds corresponds to this now-obsolete interest */ + i->before=0; } static void system_phase_hook(void *sst, uint32_t newphase) @@ -248,53 +261,118 @@ static void system_phase_hook(void *sst, uint32_t newphase) } } +#if USE_SELECT +static int fakepoll(struct pollfd *fds, int nfds, int timeout) { + fd_set infds[1], outfds[1]; + int maxfd = -1, i, rc; + struct timeval tvtimeout; + FD_ZERO(infds); + FD_ZERO(outfds); + for(i = 0; i < nfds; ++i) { + if(fds[i].events & POLLIN) + FD_SET(fds[i].fd, infds); + if(fds[i].events & POLLOUT) + FD_SET(fds[i].fd, outfds); + if(fds[i].fd > maxfd) + maxfd = fds[i].fd; + } + if(timeout != -1) { + tvtimeout.tv_sec = timeout / 1000; + tvtimeout.tv_usec = 1000 * (timeout % 1000); + } + rc = select(maxfd + 1, infds, outfds, NULL, + timeout == -1 ? NULL : &tvtimeout); + if(rc >= 0) { + for(i = 0; i < nfds; ++i) { + int revents = 0; + if(FD_ISSET(fds[i].fd, infds)) + revents |= POLLIN; + if(FD_ISSET(fds[i].fd, outfds)) + revents |= POLLOUT; + fds[i].revents = revents; + } + } + return rc; +} +#endif + +struct timeval tv_now_global; +uint64_t now_global; + static void run(void) { - struct timeval tv_now; - uint64_t now; - struct poll_interest *i; - int rv, nfds, remain, idx; + struct poll_interest *i, *itmp; + int rv, nfds, idx; int timeout; - struct pollfd *fds; - - fds=alloca(sizeof(*fds)*total_nfds); - if (!fds) { - fatal("run: couldn't alloca\n"); - } + struct pollfd *fds=0; + int allocdfds=0, shortfall=0; Message(M_NOTICE,"%s [%d]: starting\n",version,secnet_pid); do { - if (gettimeofday(&tv_now, NULL)!=0) { + if (gettimeofday(&tv_now_global, NULL)!=0) { fatal_perror("main loop: gettimeofday"); } - now=(tv_now.tv_sec*1000)+(tv_now.tv_usec/1000); + now_global=((uint64_t)tv_now_global.tv_sec*(uint64_t)1000)+ + ((uint64_t)tv_now_global.tv_usec/(uint64_t)1000); idx=0; - for (i=reg; i; i=i->next) { - i->after(i->state, fds+idx, i->nfds, &tv_now, &now); + LIST_FOREACH(i, ®, entry) { + int check; + if (interest_isregistered(i)) { + for (check=0; checknfds; check++) { + if(fds[idx+check].revents & POLLNVAL) { + fatal("run: poll (%s#%d) set POLLNVAL", i->desc, check); + } + } + i->after(i->state, fds+idx, i->nfds); + } idx+=i->nfds; } - remain=total_nfds; + if (shortfall) { + allocdfds *= 2; + allocdfds += shortfall; + fds=safe_realloc_ary(fds,sizeof(*fds),allocdfds, "run"); + } + shortfall=0; idx=0; timeout=-1; - for (i=reg; i; i=i->next) { + LIST_FOREACH_SAFE(i, ®, entry, itmp) { + int remain=allocdfds-idx; nfds=remain; - rv=i->before(i->state, fds+idx, &nfds, &timeout, &tv_now, &now); - if (rv!=0) { - /* XXX we need to handle this properly: increase the - nfds available */ - fatal("run: beforepoll_fn (%s) returns %d\n",i->desc,rv); + if (interest_isregistered(i)) { + rv=i->before(i->state, fds+idx, &nfds, &timeout); + if (rv!=0) { + if (rv!=ERANGE) + fatal("run: beforepoll_fn (%s) returns %d",i->desc,rv); + assert(nfds < INT_MAX/4 - shortfall); + shortfall += nfds-remain; + nfds=0; + timeout=0; + } + } else { + nfds=0; } if (timeout<-1) { - fatal("run: beforepoll_fn (%s) set timeout to %d\n",timeout); + fatal("run: beforepoll_fn (%s) set timeout to %d", + i->desc,timeout); + } + if (!interest_isregistered(i)) { + /* check this here, rather than earlier, so that we + handle the case where i->before() calls deregister */ + LIST_REMOVE(i, entry); + free(i); + continue; } idx+=nfds; - remain-=nfds; i->nfds=nfds; } do { if (finished) break; +#if USE_SELECT + rv=fakepoll(fds, idx, timeout); +#else rv=poll(fds, idx, timeout); +#endif if (rv<0) { if (errno!=EINTR) { fatal_perror("run: poll"); @@ -302,54 +380,77 @@ static void run(void) } } while (rv<0); } while (!finished); + free(fds); } +/* Surrender privileges, if necessary */ static void droppriv(void) +{ + if (userid) { + if (setgid(gid)!=0) + fatal_perror("can't set gid to %ld",(long)gid); + if (initgroups(userid, gid) < 0) + fatal_perror("initgroups"); + if (setuid(uid)!=0) { + fatal_perror("can't set uid to \"%s\"",userid); + } + assert(getuid() == uid); + assert(geteuid() == uid); + assert(getgid() == gid); + assert(getegid() == gid); + } +} + +/* Become a daemon, if necessary */ +static void become_daemon(void) { FILE *pf=NULL; pid_t p; + int errfds[2]; add_hook(PHASE_SHUTDOWN,system_phase_hook,NULL); - /* Open the pidfile for writing now: we may be unable to do so - once we drop privileges. */ - if (pidfile) { - pf=fopen(pidfile,"w"); - if (!pf) { - fatal_perror("cannot open pidfile \"%s\"",pidfile); - } - } - if (!background && pf) { - fprintf(pf,"%d\n",getpid()); - fclose(pf); - } - - /* Now drop privileges */ - if (uid!=0) { - if (setuid(uid)!=0) { - fatal_perror("can't set uid to \"%s\"",userid); - } - } - if (background) { + /* We only want to become a daemon if we are not one + already */ + if (background && !secnet_is_daemon) { p=fork(); if (p>0) { - if (pf) { - /* Parent process - write pidfile, exit */ - fprintf(pf,"%d\n",p); - fclose(pf); - } - exit(0); + /* Parent process - just exit */ + _exit(0); } else if (p==0) { /* Child process - all done, just carry on */ - if (pf) fclose(pf); secnet_is_daemon=True; + if (setsid() < 0) + fatal_perror("setsid"); } else { /* Error */ fatal_perror("cannot fork"); exit(1); } } + if (secnet_is_daemon) { + /* stderr etc are redirected to the system/log facility */ + pipe_cloexec(errfds); + if (dup2(errfds[1],0) < 0 + || dup2(errfds[1],1) < 0 + || dup2(errfds[1],2) < 0) + fatal_perror("can't dup2 pipe"); + if (close(errfds[1]) < 0) + fatal_perror("can't close redundant pipe endpoint"); + log_from_fd(errfds[0],"stderr",system_log); + } secnet_pid=getpid(); + + /* Now we can write the pidfile */ + if (pidfile) { + pf=fopen(pidfile,"w"); + if (!pf) { + fatal_perror("cannot open pidfile \"%s\"",pidfile); + } + if (fprintf(pf,"%ld\n",(long)secnet_pid) < 0 + || fclose(pf) < 0) + fatal_perror("cannot write to pidfile \"%s\"",pidfile); + } } static signal_notify_fn finish,ignore_hup; @@ -382,17 +483,21 @@ int main(int argc, char **argv) exit(0); } + enter_phase(PHASE_DAEMONIZE); + become_daemon(); + enter_phase(PHASE_GETRESOURCES); /* Appropriate phase hooks will have been run */ enter_phase(PHASE_DROPPRIV); droppriv(); - enter_phase(PHASE_RUN); start_signal_handling(); - request_signal_notification(SIGTERM,finish,"SIGTERM"); - if (!background) request_signal_notification(SIGINT,finish,"SIGINT"); + request_signal_notification(SIGTERM,finish,safe_strdup("SIGTERM","run")); + if (!background) request_signal_notification(SIGINT,finish, + safe_strdup("SIGINT","run")); request_signal_notification(SIGHUP,ignore_hup,NULL); + enter_phase(PHASE_RUN); run(); enter_phase(PHASE_SHUTDOWN);