/* * fetchmail.c -- main driver module for fetchmail * * For license terms, see the file COPYING in this directory. */ #include "config.h" #include #include #if defined(STDC_HEADERS) #include #endif #if defined(HAVE_UNISTD_H) #include #endif #include #include #if defined(HAVE_SYSLOG) #include #endif #include #include #include #include #include #ifdef HAVE_SETRLIMIT #include #endif /* HAVE_SETRLIMIT */ #ifdef HAVE_SYS_WAIT_H #include #endif #ifdef HAVE_GETHOSTBYNAME #include #endif /* HAVE_GETHOSTBYNAME */ #include "fetchmail.h" #include "tunable.h" #include "smtp.h" #include "getopt.h" #include "netrc.h" #ifndef ENETUNREACH #define ENETUNREACH 128 /* Interactive doesn't know this */ #endif /* ENETUNREACH */ /* prototypes for internal functions */ static int load_params(int, char **, int); static void dump_params (struct runctl *runp, struct query *, flag implicit); static int query_host(struct query *); /* controls the detail level of status/progress messages written to stderr */ int outlevel; /* see the O_.* constants above */ /* miscellaneous global controls */ struct runctl run; /* global controls for this run */ flag nodetach; /* if TRUE, don't detach daemon process */ flag quitmode; /* if --quit was set */ flag check_only; /* if --probe was set */ flag versioninfo; /* emit only version info */ char *user; /* the name of the invoking user */ char *home; /* invoking user's home directory */ char *program_name; /* the name to prefix error messages with */ flag configdump; /* dump control blocks for configurator */ const char *fetchmailhost; /* either `localhost' or the host's FQDN */ #if NET_SECURITY void *request = NULL; int requestlen = 0; #endif /* NET_SECURITY */ static char *lockfile; /* name of lockfile */ static int querystatus; /* status of query */ static int successes; /* count number of successful polls */ static int lastsig; /* last signal received */ static struct runctl cmd_run; /* global options set from command line */ static void termhook(int); /* forward declaration of exit hook */ #if 0 #define SLEEP_WITH_ALARM #endif #ifdef SLEEP_WITH_ALARM /* * The function of this variable is to remove the window during which a * SIGALRM can hose the code (ALARM is triggered *before* pause() is called). * This is a bit of a kluge; the real right thing would use sigprocmask(), * sigsuspend(). * This work around lets the interval timer trigger the first alarm after the * required interval and will then generate alarms all 5 seconds, until it * is certain, that the critical section (ie., the window) is left. */ #if defined(STDC_HEADERS) static sig_atomic_t alarm_latch = FALSE; #else /* assume int can be written in one atomic operation on non ANSI-C systems */ static int alarm_latch = FALSE; #endif RETSIGTYPE gotsigalrm(sig) int sig; { signal(sig, gotsigalrm); lastsig = sig; alarm_latch = TRUE; } #endif /* SLEEP_WITH_ALARM */ RETSIGTYPE donothing(int sig) {signal(sig, donothing); lastsig = sig;} #ifdef HAVE_ON_EXIT static void unlockit(int n, void *p) #else static void unlockit(void) #endif /* must-do actions for exit (but we can't count on being able to do malloc) */ { unlink(lockfile); } #ifdef __EMX__ /* Various EMX-specific definitions */ int itimerflag; void itimerthread(void* dummy) { if (outlevel >= O_VERBOSE) fprintf(stderr, "fetchmail: thread sleeping for %d sec.\n", poll_interval); while(1) { _sleep2(poll_interval*1000); kill((getpid()), SIGALRM); } } #endif int main (int argc, char **argv) { int st, bkgd = FALSE; int parsestatus, implicitmode = FALSE; FILE *lockfp; struct query *ctl; netrc_entry *netrc_list; char *netrc_file, *tmpbuf; pid_t pid; envquery(argc, argv); #define IDFILE_NAME ".fetchids" run.idfile = (char *) xmalloc(strlen(home)+strlen(IDFILE_NAME)+2); strcpy(run.idfile, home); strcat(run.idfile, "/"); strcat(run.idfile, IDFILE_NAME); outlevel = O_NORMAL; if ((parsestatus = parsecmdline(argc,argv, &cmd_run, &cmd_opts)) < 0) exit(PS_SYNTAX); /* this hint to stdio should help messages come out in the right order */ setvbuf(stdout, NULL, _IOLBF, MSGBUFSIZE); if (versioninfo) { printf("This is fetchmail release %s", RELEASE_ID); #ifdef POP2_ENABLE printf("+POP2"); #endif /* POP2_ENABLE */ #ifndef POP3_ENABLE printf("-POP3"); #endif /* POP3_ENABLE */ #ifndef IMAP_ENABLE printf("-IMAP"); #endif /* IMAP_ENABLE */ #ifdef GSSAPI printf("+IMAP-GSS"); #endif /* GSSAPI */ #ifdef RPA_ENABLE printf("+RPA"); #endif /* RPA_ENABLE */ #ifdef SDPS_ENABLE printf("+SDPS"); #endif /* SDPS_ENABLE */ #ifndef ETRN_ENABLE printf("-ETRN"); #endif /* ETRN_ENABLE */ #if OPIE printf("+OPIE"); #endif /* OPIE */ #if INET6 printf("+INET6"); #endif /* INET6 */ #if NET_SECURITY printf("+NETSEC"); #endif /* NET_SECURITY */ putchar('\n'); /* this is an attempt to help remote debugging */ system("uname -a"); } /* avoid parsing the config file if all we're doing is killing a daemon */ if (!(quitmode && argc == 2)) implicitmode = load_params(argc, argv, optind); /* set up to do lock protocol */ #define FETCHMAIL_PIDFILE "fetchmail.pid" xalloca(tmpbuf, char *, strlen(home) + strlen(FETCHMAIL_PIDFILE) + 3); if (!getuid()) sprintf(tmpbuf, "%s/%s", PID_DIR, FETCHMAIL_PIDFILE); else { strcpy(tmpbuf, home); strcat(tmpbuf, "/."); strcat(tmpbuf, FETCHMAIL_PIDFILE); } #undef FETCHMAIL_PIDFILE /* perhaps we just want to check options? */ if (versioninfo) { printf("Taking options from command line"); if (access(rcfile, 0)) printf("\n"); else printf(" and %s\n", rcfile); if (outlevel >= O_VERBOSE) printf("Lockfile at %s\n", tmpbuf); if (querylist == NULL) (void) fprintf(stderr, "No mailservers set up -- perhaps %s is missing?\n", rcfile); else dump_params(&run, querylist, implicitmode); exit(0); } /* dump options as a Python dictionary, for configurator use */ if (configdump) { dump_config(&run, querylist); exit(0); } /* check for another fetchmail running concurrently */ pid = -1; if ((lockfile = (char *) malloc(strlen(tmpbuf) + 1)) == NULL) { fprintf(stderr,"fetchmail: cannot allocate memory for lock name.\n"); exit(PS_EXCLUDE); } else (void) strcpy(lockfile, tmpbuf); if ((lockfp = fopen(lockfile, "r")) != NULL ) { bkgd = (fscanf(lockfp,"%d %d", &pid, &st) == 2); if (kill(pid, 0) == -1) { fprintf(stderr,"fetchmail: removing stale lockfile\n"); pid = -1; bkgd = FALSE; unlink(lockfile); } fclose(lockfp); } /* if no mail servers listed and nothing in background, we're done */ if (!(quitmode && argc == 2) && pid == -1 && querylist == NULL) { (void)fputs("fetchmail: no mailservers have been specified.\n",stderr); exit(PS_SYNTAX); } /* perhaps user asked us to kill the other fetchmail */ if (quitmode) { if (pid == -1) { fprintf(stderr,"fetchmail: no other fetchmail is running\n"); if (argc == 2) exit(PS_EXCLUDE); } else if (kill(pid, SIGTERM) < 0) { fprintf(stderr,"fetchmail: error killing %s fetchmail at %d; bailing out.\n", bkgd ? "background" : "foreground", pid); exit(PS_EXCLUDE); } else { fprintf(stderr,"fetchmail: %s fetchmail at %d killed.\n", bkgd ? "background" : "foreground", pid); unlink(lockfile); if (argc == 2) exit(0); else pid = -1; } } /* another fetchmail is running -- wake it up or die */ if (pid != -1) { if (check_only) { fprintf(stderr, "fetchmail: can't check mail while another fetchmail to same host is running.\n"); return(PS_EXCLUDE); } else if (!implicitmode) { fprintf(stderr, "fetchmail: can't poll specified hosts with another fetchmail running at %d.\n", pid); return(PS_EXCLUDE); } else if (!bkgd) { fprintf(stderr, "fetchmail: another foreground fetchmail is running at %d.\n", pid); return(PS_EXCLUDE); } else if (argc > 1) { fprintf(stderr, "fetchmail: can't accept options while a background fetchmail is running.\n"); return(PS_EXCLUDE); } else if (kill(pid, SIGUSR1) == 0) { fprintf(stderr, "fetchmail: background fetchmail at %d awakened.\n", pid); return(0); } else { /* * Should never happen -- possible only if a background fetchmail * croaks after the first kill probe above but before the * SIGUSR1/SIGHUP transmission. */ fprintf(stderr, "fetchmail: elder sibling at %d died mysteriously.\n", pid); return(PS_UNDEFINED); } } /* parse the ~/.netrc file (if present) for future password lookups. */ xalloca(netrc_file, char *, strlen (home) + 8); strcpy (netrc_file, home); strcat (netrc_file, "/.netrc"); netrc_list = parse_netrc(netrc_file); #ifdef HAVE_SETRLIMIT /* * Before getting passwords, disable core dumps unless -v -d0 mode is on. * Core dumps could otherwise contain passwords to be scavenged by a * cracker. */ if (outlevel < O_VERBOSE || run.poll_interval > 0) { struct rlimit corelimit; corelimit.rlim_cur = 0; corelimit.rlim_max = 0; setrlimit(RLIMIT_CORE, &corelimit); } #endif /* HAVE_SETRLIMIT */ /* pick up interactively any passwords we need but don't have */ for (ctl = querylist; ctl; ctl = ctl->next) { ctl->authfailcount = 0; if (ctl->active && !(implicitmode && ctl->server.skip)&&!ctl->password) { if (ctl->server.preauthenticate == A_KERBEROS_V4 || ctl->server.preauthenticate == A_KERBEROS_V5 || #ifdef GSSAPI ctl->server.protocol == P_IMAP_GSS || #endif /* GSSAPI */ ctl->server.protocol == P_IMAP_K4) /* Server won't care what the password is, but there must be some non-null string here. */ ctl->password = ctl->remotename; else { /* look up the host and account in the .netrc file. */ netrc_entry *p = search_netrc(netrc_list,ctl->server.pollname); while (p && strcmp(p->account, ctl->remotename)) p = search_netrc(p->next, ctl->remotename); /* if we find a matching entry with a password, use it */ if (p && p->password) ctl->password = xstrdup(p->password); } if (ctl->server.protocol != P_ETRN && ctl->server.protocol != P_IMAP_K4 #ifdef GSSAPI && ctl->server.protocol != P_IMAP_GSS #endif /* GSSAPI */ && !ctl->password) { #define PASSWORD_PROMPT "Enter password for %s@%s: " xalloca(tmpbuf, char *, strlen(PASSWORD_PROMPT) + strlen(ctl->remotename) + strlen(ctl->server.pollname) + 1); (void) sprintf(tmpbuf, PASSWORD_PROMPT, ctl->remotename, ctl->server.pollname); ctl->password = xstrdup((char *)getpassword(tmpbuf)); #undef PASSWORD_PROMPT } } } /* * Maybe time to go to demon mode... */ #if defined(HAVE_SYSLOG) if (run.use_syslog) { openlog(program_name, LOG_PID, LOG_MAIL); error_init(-1); } else #endif error_init((run.poll_interval == 0 || nodetach) && !run.logfile); if (run.poll_interval) { if (!nodetach) daemonize(run.logfile, termhook); error( 0, 0, "starting fetchmail %s daemon ", RELEASE_ID); /* * We'll set up a handler for these when we're sleeping, * but ignore them otherwise so as not to interrupt a poll. */ signal(SIGUSR1, SIG_IGN); if (run.poll_interval && !getuid()) signal(SIGHUP, SIG_IGN); } /* beyond here we don't want more than one fetchmail running per user */ umask(0077); signal(SIGABRT, termhook); signal(SIGINT, termhook); signal(SIGTERM, termhook); signal(SIGALRM, termhook); signal(SIGPIPE, termhook); signal(SIGQUIT, termhook); /* here's the exclusion lock */ if ((lockfp = fopen(lockfile,"w")) != NULL) { fprintf(lockfp,"%d",getpid()); if (run.poll_interval) fprintf(lockfp," %d", run.poll_interval); fclose(lockfp); #ifdef HAVE_ATEXIT atexit(unlockit); #endif #ifdef HAVE_ON_EXIT on_exit(unlockit, (char *)NULL); #endif } /* * Query all hosts. If there's only one, the error return will * reflect the status of that transaction. */ do { #if defined(HAVE_RES_SEARCH) && defined(USE_TCPIP_FOR_DNS) /* * This was an efficiency hack that backfired. The theory * was that using TCP/IP for DNS queries would get us better * reliability and shave off some per-UDP-packet costs. * Unfortunately it interacted badly with diald, which effectively * filters out DNS queries over TCP/IP for reasons having to do * with some obscure kernel problem involving bootstrapping of * dynamically-addressed links. I don't understand this mess * and don't want to, so it's "See ya!" to this hack. */ sethostent(TRUE); /* use TCP/IP for mailserver queries */ #endif /* HAVE_RES_SEARCH */ batchcount = 0; for (ctl = querylist; ctl; ctl = ctl->next) { if (ctl->authfailcount) { error(0, -1, "poll of %s skipped until authentication is unwedged", ctl->server.pollname); continue; } if (ctl->active && !(implicitmode && ctl->server.skip)) { /* check skip interval first so that it counts all polls */ if (run.poll_interval && ctl->server.interval) { if (ctl->server.poll_count++ % ctl->server.interval) { if (outlevel >= O_VERBOSE) error(0, -1, "interval not reached, not querying %s", ctl->server.pollname); continue; } } #if defined(linux) && !INET6 /* interface_approve() does its own error logging */ if (!interface_approve(&ctl->server)) continue; #endif /* defined(linux) && !INET6 */ querystatus = query_host(ctl); if (querystatus == PS_SUCCESS) { successes++; #ifdef POP3_ENABLE if (!check_only) update_str_lists(ctl); /* Save UID list to prevent re-fetch in case fetchmail recover from crash */ if (!check_only) { write_saved_lists(querylist, run.idfile); if (outlevel >= O_DEBUG) error(0, 0, "saved UID List"); } #endif /* POP3_ENABLE */ } else if (!check_only && ((querystatus!=PS_NOMAIL) || (outlevel==O_DEBUG))) error(0, 0, "Query status=%d", querystatus); #if defined(linux) && !INET6 if (ctl->server.monitor) { /* * Allow some time for the link to quiesce. One * second is usually sufficient, three is safe. * Note: this delay is important - don't remove! */ sleep(3); interface_note_activity(&ctl->server); } #endif /* defined(linux) && !INET6 */ } } #if defined(HAVE_RES_SEARCH) && defined(USE_TCPIP_FOR_DNS) endhostent(); /* release TCP/IP connection to nameserver */ #endif /* HAVE_RES_SEARCH */ /* * Close all SMTP delivery sockets. For optimum performance * we'd like to hold them open til end of run, but (1) this * loses if our poll interval is longer than the MTA's inactivity * timeout, and (2) some MTAs (like smail) don't deliver after * each message, but rather queue up mail and wait to actually * deliver it until the input socket is closed. */ for (ctl = querylist; ctl; ctl = ctl->next) if (ctl->smtp_socket != -1) { SMTP_quit(ctl->smtp_socket); close(ctl->smtp_socket); ctl->smtp_socket = -1; } /* * OK, we've polled. Now sleep. */ if (run.poll_interval) { /* * Because passwords can expire, it may happen that *all* * hosts are now out of the loop due to authfail * conditions. If this happens daemon-mode fetchmail * should softly and silently vanish away, rather than * spinning uselessly. */ int auth_ok = 0; for (ctl = querylist; ctl; ctl = ctl->next) if (!ctl->authfailcount) auth_ok++; if (!auth_ok) { error(0, -1, "All authentications have failed. Exiting."); exit(PS_AUTHFAIL); } if (outlevel >= O_VERBOSE) error(0, -1, "fetchmail: sleeping at %s", rfc822timestamp()); /* * With this simple hack, we make it possible for a foreground * fetchmail to wake up one in daemon mode. What we want is the * side effect of interrupting any sleep that may be going on, * forcing fetchmail to re-poll its hosts. The second line is * for people who think all system daemons wake up on SIGHUP. */ signal(SIGUSR1, donothing); if (!getuid()) signal(SIGHUP, donothing); /* * We can't use sleep(3) here because we need an alarm(3) * equivalent in order to implement server nonresponse timeout. * We'll just assume setitimer(2) is available since fetchmail * has to have a BSDoid socket layer to work at all. */ { #ifndef __EMX__ #ifdef SLEEP_WITH_ALARM /* not normally on */ /* * This code stopped working under glibc-2, apparently due * to the change in signal(2) semantics. (The siginterrupt * line, added later, should fix this problem.) John Stracke * wrote: * * The problem seems to be that, after hitting the interval * timer while talking to the server, the process no longer * responds to SIGALRM. I put in printf()s to see when it * reached the pause() for the poll interval, and I checked * the return from setitimer(), and everything seemed to be * working fine, except that the pause() just ignored SIGALRM. * I thought maybe the itimer wasn't being fired, so I hit * it with a SIGALRM from the command line, and it ignored * that, too. SIGUSR1 woke it up just fine, and it proceeded * to repoll--but, when the dummy server didn't respond, it * never timed out, and SIGALRM wouldn't make it. * * (continued below...) */ struct itimerval ntimeout; ntimeout.it_interval.tv_sec = 5; /* repeat alarm every 5 secs */ ntimeout.it_interval.tv_usec = 0; ntimeout.it_value.tv_sec = run.poll_interval; ntimeout.it_value.tv_usec = 0; siginterrupt(SIGALRM, 1); alarm_latch = FALSE; signal(SIGALRM, gotsigalrm); /* first trap signals */ setitimer(ITIMER_REAL,&ntimeout,NULL); /* then start timer */ /* there is a very small window between the next two lines */ /* which could result in a deadlock. But this will now be */ /* caught by periodical alarms (see it_interval) */ if (!alarm_latch) pause(); /* stop timer */ ntimeout.it_interval.tv_sec = ntimeout.it_interval.tv_usec = 0; ntimeout.it_value.tv_sec = ntimeout.it_value.tv_usec = 0; setitimer(ITIMER_REAL,&ntimeout,NULL); /* now stop timer */ signal(SIGALRM, SIG_IGN); #else /* * So the workaround I used is to make it sleep by using * select() instead of setitimer()/pause(). select() is * perfectly happy being called with a timeout and * no file descriptors; it just sleeps until it hits the * timeout. The only concern I had was that it might * implement its timeout with SIGALRM--there are some * Unices where this is done, because select() is a library * function--but apparently not. */ struct timeval timeout; timeout.tv_sec = run.poll_interval; timeout.tv_usec = 0; lastsig = 0; select(0,0,0,0, &timeout); #endif #else /* EMX */ alarm_latch = FALSE; signal(SIGALRM, gotsigalrm); _beginthread(itimerthread, NULL, 32768, NULL); /* see similar code above */ if (!alarm_latch) pause(); signal(SIGALRM, SIG_IGN); #endif /* ! EMX */ if (lastsig == SIGUSR1 || ((run.poll_interval && !getuid()) && lastsig == SIGHUP)) { #ifdef SYS_SIGLIST_DECLARED error(0, 0, "awakened by %s", sys_siglist[lastsig]); #else error(0, 0, "awakened by signal %d", lastsig); #endif } } /* now lock out interrupts again */ signal(SIGUSR1, SIG_IGN); if (!getuid()) signal(SIGHUP, SIG_IGN); if (outlevel >= O_VERBOSE) error(0, -1, "awakened at %s", rfc822timestamp()); } } while (run.poll_interval); if (outlevel >= O_VERBOSE) error(0, -1, "normal termination, status %d", successes ? PS_SUCCESS : querystatus); termhook(0); exit(successes ? PS_SUCCESS : querystatus); } static void optmerge(struct query *h2, struct query *h1, int force) /* merge two options records */ { /* * If force is off, modify h2 fields only when they're empty (treat h1 * as defaults). If force is on, modify each h2 field whenever h1 * is nonempty (treat h1 as an override). */ #define LIST_MERGE(dstl, srcl) if (force ? !!srcl : !dstl) \ free_str_list(&dstl), \ append_str_list(&dstl, &srcl) LIST_MERGE(h2->server.localdomains, h1->server.localdomains); LIST_MERGE(h2->localnames, h1->localnames); LIST_MERGE(h2->mailboxes, h1->mailboxes); LIST_MERGE(h2->smtphunt, h1->smtphunt); LIST_MERGE(h2->antispam, h1->antispam); #undef LIST_MERGE #define FLAG_MERGE(fld) if (force ? !!h1->fld : !h2->fld) h2->fld = h1->fld FLAG_MERGE(server.via); FLAG_MERGE(server.protocol); #if INET6 FLAG_MERGE(server.service); FLAG_MERGE(server.netsec); #else /* INET6 */ FLAG_MERGE(server.port); #endif /* INET6 */ FLAG_MERGE(server.interval); FLAG_MERGE(server.preauthenticate); FLAG_MERGE(server.timeout); FLAG_MERGE(server.envelope); FLAG_MERGE(server.envskip); FLAG_MERGE(server.qvirtual); FLAG_MERGE(server.skip); FLAG_MERGE(server.dns); FLAG_MERGE(server.checkalias); FLAG_MERGE(server.uidl); #ifdef linux FLAG_MERGE(server.interface); FLAG_MERGE(server.monitor); FLAG_MERGE(server.interface_pair); #endif /* linux */ FLAG_MERGE(wildcard); FLAG_MERGE(remotename); FLAG_MERGE(password); FLAG_MERGE(mda); FLAG_MERGE(bsmtp); FLAG_MERGE(smtpaddress); FLAG_MERGE(preconnect); FLAG_MERGE(postconnect); FLAG_MERGE(keep); FLAG_MERGE(flush); FLAG_MERGE(fetchall); FLAG_MERGE(rewrite); FLAG_MERGE(forcecr); FLAG_MERGE(stripcr); FLAG_MERGE(pass8bits); FLAG_MERGE(dropstatus); FLAG_MERGE(mimedecode); FLAG_MERGE(limit); FLAG_MERGE(warnings); FLAG_MERGE(fetchlimit); FLAG_MERGE(batchlimit); FLAG_MERGE(expunge); FLAG_MERGE(properties); #undef FLAG_MERGE } static int load_params(int argc, char **argv, int optind) { int implicitmode, st; struct passwd *pw; struct query def_opts, *ctl; memset(&def_opts, '\0', sizeof(struct query)); def_opts.smtp_socket = -1; def_opts.smtpaddress = (char *)0; save_str(&def_opts.antispam, STRING_DUMMY, 0)->val.status.num = 571; save_str(&def_opts.antispam, STRING_DUMMY, 0)->val.status.num = 550; save_str(&def_opts.antispam, STRING_DUMMY, 0)->val.status.num = 501; def_opts.server.protocol = P_AUTO; def_opts.server.timeout = CLIENT_TIMEOUT; def_opts.warnings = WARNING_INTERVAL; def_opts.remotename = user; def_opts.expunge = 1; /* this builds the host list */ if (prc_parse_file(rcfile, !versioninfo) != 0) exit(PS_SYNTAX); if ((implicitmode = (optind >= argc))) { for (ctl = querylist; ctl; ctl = ctl->next) ctl->active = TRUE; } else for (; optind < argc; optind++) { flag predeclared = FALSE; /* * If hostname corresponds to a host known from the rc file, * simply declare it active. Otherwise synthesize a host * record from command line and defaults */ for (ctl = querylist; ctl; ctl = ctl->next) if (!strcmp(ctl->server.pollname, argv[optind]) || str_in_list(&ctl->server.akalist, argv[optind], TRUE)) { /* Is this correct? */ if(predeclared) fprintf(stderr,"Warning: multiple mentions of host %s in config file\n",argv[optind]); ctl->active = TRUE; predeclared = TRUE; } if (!predeclared) { /* * Allocate and link record without copying in * command-line args; we'll do that with the optmerge * call later on. */ ctl = hostalloc((struct query *)NULL); ctl->server.via = ctl->server.pollname = xstrdup(argv[optind]); ctl->active = TRUE; ctl->server.lead_server = (struct hostdata *)NULL; } } /* * If there's a defaults record, merge it and lose it. */ if (querylist && strcmp(querylist->server.pollname, "defaults") == 0) { for (ctl = querylist->next; ctl; ctl = ctl->next) optmerge(ctl, querylist, FALSE); querylist = querylist->next; } /* don't allow a defaults record after the first */ for (ctl = querylist; ctl; ctl = ctl->next) if (ctl != querylist && strcmp(ctl->server.pollname, "defaults") == 0) exit(PS_SYNTAX); /* use localhost if we never fetch the FQDN of this host */ fetchmailhost = "localhost"; /* merge in wired defaults, do sanity checks and prepare internal fields */ for (ctl = querylist; ctl; ctl = ctl->next) { if (configdump || (ctl->active && !(implicitmode && ctl->server.skip))) { /* merge in defaults */ optmerge(ctl, &def_opts, FALSE); /* force command-line options */ optmerge(ctl, &cmd_opts, TRUE); /* this code enables flags to be turned off */ #define DEFAULT(flag, dflt) if (flag == FLAG_TRUE)\ flag = TRUE;\ else if (flag == FLAG_FALSE)\ flag = FALSE;\ else\ flag = (dflt) DEFAULT(ctl->keep, FALSE); DEFAULT(ctl->fetchall, FALSE); DEFAULT(ctl->flush, FALSE); DEFAULT(ctl->rewrite, TRUE); DEFAULT(ctl->stripcr, (ctl->mda != (char *)NULL)); DEFAULT(ctl->forcecr, FALSE); DEFAULT(ctl->pass8bits, FALSE); DEFAULT(ctl->dropstatus, FALSE); DEFAULT(ctl->mimedecode, FALSE); DEFAULT(ctl->server.dns, TRUE); DEFAULT(ctl->server.uidl, FALSE); DEFAULT(ctl->server.checkalias, FALSE); #undef DEFAULT /* * DNS support is required for some protocols. * * If we're using ETRN, the smtp hunt list is the list of * systems we're polling on behalf of; these have to be * fully-qualified domain names. The default for this list * should be the FQDN of localhost. * * If we're using Kerberos for authentication, we need * the FQDN in order to generate capability keys. */ if (ctl->server.protocol == P_ETRN || ctl->server.preauthenticate == A_KERBEROS_V4 || ctl->server.preauthenticate == A_KERBEROS_V5) if (strcmp(fetchmailhost, "localhost") == 0) fetchmailhost = host_fqdn(); /* * Make sure we have a nonempty host list to forward to. */ if (!ctl->smtphunt) save_str(&ctl->smtphunt, fetchmailhost, FALSE); /* if `user' doesn't name a real local user, try to run as root */ if ((pw = getpwnam(user)) == (struct passwd *)NULL) ctl->uid = 0; else ctl->uid = pw->pw_uid; /* for local delivery via MDA */ if (!ctl->localnames) /* for local delivery via SMTP */ save_str_pair(&ctl->localnames, user, NULL); #if !defined(HAVE_GETHOSTBYNAME) || !defined(HAVE_RES_SEARCH) /* can't handle multidrop mailboxes unless we can do DNS lookups */ if (ctl->localnames && ctl->localnames->next && ctl->server.dns) { ctl->server.dns = FALSE; fprintf(stderr, "fetchmail: warning: no DNS available to check multidrop fetches from %s\n", ctl->server.pollname); } #endif /* !HAVE_GETHOSTBYNAME || !HAVE_RES_SEARCH */ /* * * Compute the true name of the mailserver host. * There are two clashing cases here: * * (1) The poll name is a label, possibly on one of several * poll configurations for the same host. In this case * the `via' option will be present and give the true name. * * (2) The poll name is the true one, the via name is * localhost. This is going to be typical for ssh-using * configurations. * * We're going to assume the via name is true unless it's * localhost. */ if (ctl->server.via && strcmp(ctl->server.via, "localhost")) ctl->server.queryname = xstrdup(ctl->server.via); else ctl->server.queryname = xstrdup(ctl->server.pollname); /* * We may have to canonicalize the server truename for later use. * Do this just once for each lead server, if necessary, in order * to minimize DNS round trips. */ if (ctl->server.lead_server) ctl->server.truename = xstrdup(ctl->server.lead_server->truename); #ifdef HAVE_GETHOSTBYNAME else if (ctl->server.preauthenticate==A_KERBEROS_V4 || ctl->server.preauthenticate==A_KERBEROS_V5 || (ctl->server.dns && MULTIDROP(ctl))) { struct hostent *namerec; /* compute the canonical name of the host */ errno = 0; namerec = gethostbyname(ctl->server.queryname); if (namerec == (struct hostent *)NULL) { error(0, errno, "couldn't find canonical DNS name of %s", ctl->server.pollname); exit(PS_DNS); } else ctl->server.truename=xstrdup((char *)namerec->h_name); } #endif /* HAVE_GETHOSTBYNAME */ else ctl->server.truename = xstrdup(ctl->server.queryname); /* if no folders were specified, set up the null one as default */ if (!ctl->mailboxes) save_str(&ctl->mailboxes, (char *)NULL, 0); /* maybe user overrode timeout on command line? */ if (ctl->server.timeout == -1) ctl->server.timeout = CLIENT_TIMEOUT; #if !INET6 /* sanity checks */ if (ctl->server.port < 0) { (void) fprintf(stderr, "%s configuration invalid, port number cannot be negative", ctl->server.pollname); exit(PS_SYNTAX); } if (ctl->server.protocol == P_RPOP && ctl->server.port >= 1024) { (void) fprintf(stderr, "%s configuration invalid, RPOP requires a privileged port", ctl->server.pollname); exit(PS_SYNTAX); } #endif /* !INET6 */ } } /* here's where we override globals */ if (cmd_run.logfile) run.logfile = cmd_run.logfile; if (cmd_run.idfile) run.idfile = cmd_run.idfile; if (cmd_run.poll_interval >= 0) run.poll_interval = cmd_run.poll_interval; if (cmd_run.invisible) run.invisible = cmd_run.invisible; if (cmd_run.use_syslog) run.use_syslog = (cmd_run.use_syslog == FLAG_TRUE); /* check and daemon options are not compatible */ if (check_only && run.poll_interval) run.poll_interval = 0; #ifdef POP3_ENABLE /* initialize UID handling */ if (!versioninfo && (st = prc_filecheck(run.idfile, !versioninfo)) != 0) exit(st); else initialize_saved_lists(querylist, run.idfile); #endif /* POP3_ENABLE */ /* * If the user didn't set a last-resort user to get misaddressed * multidrop mail, set an appropriate default here. */ if (!run.postmaster) if (getuid()) /* ordinary user */ run.postmaster = user; else /* root */ run.postmaster = "postmaster"; return(implicitmode); } void termhook(int sig) /* to be executed on normal or signal-induced termination */ { struct query *ctl; /* * Sending SMTP QUIT on signal is theoretically nice, but led to a * subtle bug. If fetchmail was terminated by signal while it was * shipping message text, it would hang forever waiting for a * command acknowledge. In theory we could enable the QUIT * only outside of the message send. In practice, we don't * care. All mailservers hang up on a dropped TCP/IP connection * anyway. */ if (sig != 0) error(0, 0, "terminated with signal %d", sig); else /* terminate all SMTP connections cleanly */ for (ctl = querylist; ctl; ctl = ctl->next) if (ctl->smtp_socket != -1) SMTP_quit(ctl->smtp_socket); #ifdef POP3_ENABLE if (!check_only) write_saved_lists(querylist, run.idfile); #endif /* POP3_ENABLE */ /* * Craig Metz, the RFC1938 one-time-password guy, points out: * "Remember that most kernels don't zero pages before handing them to the * next process and many kernels share pages between user and kernel space. * You'd be very surprised what you can find from a short program to do a * malloc() and then dump the contents of the pages you got. By zeroing * the secrets at end of run (earlier if you can), you make sure the next * guy can't get the password/pass phrase." * * Right you are, Craig! */ for (ctl = querylist; ctl; ctl = ctl->next) if (ctl->password) memset(ctl->password, '\0', strlen(ctl->password)); #if !defined(HAVE_ATEXIT) && !defined(HAVE_ON_EXIT) unlockit(); #endif exit(successes ? PS_SUCCESS : querystatus); } /* * Sequence of protocols to try when autoprobing, most capable to least. */ static const int autoprobe[] = { #ifdef IMAP_ENABLE P_IMAP, #endif /* IMAP_ENABLE */ #ifdef POP3_ENABLE P_POP3, #endif /* POP3_ENABLE */ #ifdef POP2_ENABLE P_POP2 #endif /* POP2_ENABLE */ }; static int query_host(struct query *ctl) /* perform fetch transaction with single host */ { int i, st; if (outlevel >= O_VERBOSE) { time_t now; time(&now); error(0, -1, "fetchmail: %s querying %s (protocol %s) at %s", RELEASE_ID, ctl->server.pollname, showproto(ctl->server.protocol), ctime(&now)); } switch (ctl->server.protocol) { case P_AUTO: for (i = 0; i < sizeof(autoprobe)/sizeof(autoprobe[0]); i++) { ctl->server.protocol = autoprobe[i]; if ((st = query_host(ctl)) == PS_SUCCESS || st == PS_NOMAIL || st == PS_AUTHFAIL || st == PS_LOCKBUSY || st == PS_SMTP) break; } ctl->server.protocol = P_AUTO; return(st); break; case P_POP2: #ifdef POP2_ENABLE return(doPOP2(ctl)); #else error(0, -1, "POP2 support is not configured.\n"); return(PS_PROTOCOL); #endif /* POP2_ENABLE */ break; case P_POP3: case P_APOP: case P_RPOP: #ifdef POP3_ENABLE return(doPOP3(ctl)); #else error(0, -1, "POP3 support is not configured.\n"); return(PS_PROTOCOL); #endif /* POP3_ENABLE */ break; case P_IMAP: case P_IMAP_K4: #ifdef GSSAPI case P_IMAP_GSS: #endif /* GSSAPI */ #ifdef IMAP_ENABLE return(doIMAP(ctl)); #else error(0, -1, "IMAP support is not configured.\n"); return(PS_PROTOCOL); #endif /* IMAP_ENABLE */ break; case P_ETRN: #ifndef ETRN_ENABLE error(0, -1, "ETRN support is not configured.\n"); return(PS_PROTOCOL); #else #ifdef HAVE_GETHOSTBYNAME return(doETRN(ctl)); #else error(0, -1, "Cannot support ETRN without gethostbyname(2).\n"); return(PS_PROTOCOL); #endif /* HAVE_GETHOSTBYNAME */ #endif /* ETRN_ENABLE */ default: error(0, 0, "unsupported protocol selected."); return(PS_PROTOCOL); } } void dump_params (struct runctl *runp, struct query *querylist, flag implicit) /* display query parameters in English */ { struct query *ctl; if (runp->poll_interval) printf("Poll interval is %d seconds\n", runp->poll_interval); if (runp->logfile) printf("Logfile is %s\n", runp->logfile); if (strcmp(runp->idfile, IDFILE_NAME)) printf("Idfile is %s\n", runp->idfile); #if defined(HAVE_SYSLOG) if (runp->use_syslog) printf("Progress messages will be logged via syslog\n"); #endif if (runp->invisible) printf("Fetchmail will masquerade and will not generate Received\n"); if (runp->postmaster) printf("Fetchmail will forward misaddressed multidrop messages to %s.\n", runp->postmaster); for (ctl = querylist; ctl; ctl = ctl->next) { if (!ctl->active || (implicit && ctl->server.skip)) continue; printf("Options for retrieving from %s@%s:\n", ctl->remotename, visbuf(ctl->server.pollname)); if (ctl->server.via && (ctl->server.protocol != P_ETRN)) printf(" Mail will be retrieved via %s\n", ctl->server.via); if (ctl->server.interval) printf(" Poll of this server will occur every %d intervals.\n", ctl->server.interval); if (ctl->server.truename) printf(" True name of server is %s.\n", ctl->server.truename); if (ctl->server.skip || outlevel >= O_VERBOSE) printf(" This host will%s be queried when no host is specified.\n", ctl->server.skip ? " not" : ""); /* * Don't poll for password when there is one or when using the ETRN * or IMAP-GSS protocol */ if (!ctl->password && (ctl->server.protocol != P_ETRN) #ifdef GSSAPI && (ctl->server.protocol != P_IMAP_GSS) #endif /* GSSAPI */ ) printf(" Password will be prompted for.\n"); else if (outlevel >= O_VERBOSE) if (ctl->server.protocol == P_APOP) printf(" APOP secret = \"%s\".\n", visbuf(ctl->password)); else if (ctl->server.protocol == P_RPOP) printf(" RPOP id = \"%s\".\n", visbuf(ctl->password)); else printf(" Password = \"%s\".\n", visbuf(ctl->password)); if (ctl->server.protocol == P_POP3 #if INET6 && !strcmp(ctl->server.service, KPOP_PORT) #else /* INET6 */ && ctl->server.port == KPOP_PORT #endif /* INET6 */ && (ctl->server.preauthenticate == A_KERBEROS_V4 || ctl->server.preauthenticate == A_KERBEROS_V5)) printf(" Protocol is KPOP with Kerberos %s authentication", ctl->server.preauthenticate == A_KERBEROS_V5 ? "V" : "IV"); else printf(" Protocol is %s", showproto(ctl->server.protocol)); #if INET6 if (ctl->server.service) printf(" (using service %s)", ctl->server.service); if (ctl->server.netsec) printf(" (using network security options %s)", ctl->server.netsec); #else /* INET6 */ if (ctl->server.port) printf(" (using port %d)", ctl->server.port); #endif /* INET6 */ else if (outlevel >= O_VERBOSE) printf(" (using default port)"); if (ctl->server.uidl && (ctl->server.protocol != P_ETRN)) printf(" (forcing UIDL use)"); putchar('.'); putchar('\n'); if (ctl->server.preauthenticate == A_KERBEROS_V4) printf(" Kerberos V4 preauthentication enabled.\n"); if (ctl->server.preauthenticate == A_KERBEROS_V5) printf(" Kerberos V5 preauthentication enabled.\n"); if (ctl->server.timeout > 0) printf(" Server nonresponse timeout is %d seconds", ctl->server.timeout); if (ctl->server.timeout == CLIENT_TIMEOUT) printf(" (default).\n"); else printf(".\n"); if (ctl->server.protocol != P_ETRN) { if (!ctl->mailboxes->id) printf(" Default mailbox selected.\n"); else { struct idlist *idp; printf(" Selected mailboxes are:"); for (idp = ctl->mailboxes; idp; idp = idp->next) printf(" %s", idp->id); printf("\n"); } printf(" %s messages will be retrieved (--all %s).\n", ctl->fetchall ? "All" : "Only new", ctl->fetchall ? "on" : "off"); printf(" Fetched messages will%s be kept on the server (--keep %s).\n", ctl->keep ? "" : " not", ctl->keep ? "on" : "off"); printf(" Old messages will%s be flushed before message retrieval (--flush %s).\n", ctl->flush ? "" : " not", ctl->flush ? "on" : "off"); printf(" Rewrite of server-local addresses is %sabled (--norewrite %s).\n", ctl->rewrite ? "en" : "dis", ctl->rewrite ? "off" : "on"); printf(" Carriage-return stripping is %sabled (stripcr %s).\n", ctl->stripcr ? "en" : "dis", ctl->stripcr ? "on" : "off"); printf(" Carriage-return forcing is %sabled (forcecr %s).\n", ctl->forcecr ? "en" : "dis", ctl->forcecr ? "on" : "off"); printf(" Interpretation of Content-Transfer-Encoding is %sabled (pass8bits %s).\n", ctl->pass8bits ? "dis" : "en", ctl->pass8bits ? "on" : "off"); printf(" MIME decoding is %sabled (mimedecode %s).\n", ctl->mimedecode ? "en" : "dis", ctl->mimedecode ? "on" : "off"); printf(" Nonempty Status lines will be %s (dropstatus %s)\n", ctl->dropstatus ? "discarded" : "kept", ctl->dropstatus ? "on" : "off"); if (NUM_NONZERO(ctl->limit)) { if (NUM_NONZERO(ctl->limit)) printf(" Message size limit is %d bytes (--limit %d).\n", ctl->limit, ctl->limit); else if (outlevel >= O_VERBOSE) printf(" No message size limit (--limit 0).\n"); if (run.poll_interval > 0) printf(" Message size warning interval is %d seconds (--warnings %d).\n", ctl->warnings, ctl->warnings); else if (outlevel >= O_VERBOSE) printf(" Size warnings on every poll (--warnings 0).\n"); } if (NUM_NONZERO(ctl->fetchlimit)) printf(" Received-message limit is %d (--fetchlimit %d).\n", ctl->fetchlimit, ctl->fetchlimit); else if (outlevel >= O_VERBOSE) printf(" No received-message limit (--fetchlimit 0).\n"); if (NUM_NONZERO(ctl->batchlimit)) printf(" SMTP message batch limit is %d.\n", ctl->batchlimit); else if (outlevel >= O_VERBOSE) printf(" No SMTP message batch limit (--batchlimit 0).\n"); if (ctl->server.protocol == P_IMAP) if (NUM_NONZERO(ctl->expunge)) printf(" Deletion interval between expunges is %d (--expunge %d).\n", ctl->expunge, ctl->expunge); else if (outlevel >= O_VERBOSE) printf(" No expunges (--expunge 0).\n"); } if (ctl->bsmtp) printf(" Messages will be appended to %s as BSMTP\n", visbuf(ctl->bsmtp)); else if (ctl->mda && (ctl->server.protocol != P_ETRN)) printf(" Messages will be delivered with \"%s\".\n", visbuf(ctl->mda)); else { struct idlist *idp; printf(" Messages will be SMTP-forwarded to:"); for (idp = ctl->smtphunt; idp; idp = idp->next) { printf(" %s", idp->id); if (!idp->val.status.mark) printf(" (default)"); } printf("\n"); if (ctl->smtpaddress) printf(" Host part of MAIL FROM line will be %s\n", ctl->smtpaddress); } if (ctl->server.protocol != P_ETRN) { if (ctl->antispam != (struct idlist *)NULL) { struct idlist *idp; printf(" Recognized listener spam block responses are:"); for (idp = ctl->antispam; idp; idp = idp->next) printf(" %d", idp->val.status.num); printf("\n"); } else if (outlevel >= O_VERBOSE) printf(" Spam-blocking disabled\n"); } if (ctl->preconnect) printf(" Server connection will be brought up with \"%s\".\n", visbuf(ctl->preconnect)); else if (outlevel >= O_VERBOSE) printf(" No pre-connection command.\n"); if (ctl->postconnect) printf(" Server connection will be taken down with \"%s\".\n", visbuf(ctl->postconnect)); else if (outlevel >= O_VERBOSE) printf(" No post-connection command.\n"); if (ctl->server.protocol != P_ETRN) { if (!ctl->localnames) printf(" No localnames declared for this host.\n"); else { struct idlist *idp; int count = 0; for (idp = ctl->localnames; idp; idp = idp->next) ++count; if (count > 1 || ctl->wildcard) printf(" Multi-drop mode: "); else printf(" Single-drop mode: "); printf("%d local name(s) recognized.\n", count); if (outlevel >= O_VERBOSE) { for (idp = ctl->localnames; idp; idp = idp->next) if (idp->val.id2) printf("\t%s -> %s\n", idp->id, idp->val.id2); else printf("\t%s\n", idp->id); if (ctl->wildcard) fputs("\t*\n", stdout); } if (count > 1 || ctl->wildcard) { printf(" DNS lookup for multidrop addresses is %sabled.\n", ctl->server.dns ? "en" : "dis"); if (ctl->server.dns) { printf(" Server aliases will be compared with multidrop addresses by "); if (ctl->server.checkalias) printf("IP address.\n"); else printf("name.\n"); } if (ctl->server.envelope == STRING_DISABLED) printf(" Envelope-address routing is disabled\n"); else { printf(" Envelope header is assumed to be: %s\n", ctl->server.envelope ? ctl->server.envelope:"Received"); if (ctl->server.envskip > 1 || outlevel >= O_VERBOSE) printf(" Number of envelope header to be parsed: %d\n", ctl->server.envskip); if (ctl->server.qvirtual) printf(" Prefix %s will be removed from user id\n", ctl->server.qvirtual); else if (outlevel >= O_VERBOSE) printf(" No prefix stripping\n"); } if (ctl->server.akalist) { struct idlist *idp; printf(" Predeclared mailserver aliases:"); for (idp = ctl->server.akalist; idp; idp = idp->next) printf(" %s", idp->id); putchar('\n'); } if (ctl->server.localdomains) { struct idlist *idp; printf(" Local domains:"); for (idp = ctl->server.localdomains; idp; idp = idp->next) printf(" %s", idp->id); putchar('\n'); } } } } #ifdef linux if (ctl->server.interface) printf(" Connection must be through interface %s.\n", ctl->server.interface); else if (outlevel >= O_VERBOSE) printf(" No interface requirement specified.\n"); if (ctl->server.monitor) printf(" Polling loop will monitor %s.\n", ctl->server.monitor); else if (outlevel >= O_VERBOSE) printf(" No monitor interface specified.\n"); #endif if (ctl->server.protocol > P_POP2 && (ctl->server.protocol != P_ETRN)) if (!ctl->oldsaved) printf(" No UIDs saved from this host.\n"); else { struct idlist *idp; int count = 0; for (idp = ctl->oldsaved; idp; idp = idp->next) ++count; printf(" %d UIDs saved.\n", count); if (outlevel >= O_VERBOSE) for (idp = ctl->oldsaved; idp; idp = idp->next) printf("\t%s\n", idp->id); } if (ctl->properties) printf(" Pass-through properties \"%s\".\n", visbuf(ctl->properties)); } } /* fetchmail.c ends here */