int mark_corrupt(VSTREAM *src) { const char *myname = "mark_corrupt"; uid_t saved_uid; gid_t saved_gid; /* * If not running as the mail system, change privileges first. */ if ((saved_uid = geteuid()) != var_owner_uid) { saved_gid = getegid(); set_eugid(var_owner_uid, var_owner_gid); } /* * For now, the result value is -1; this may become a bit mask, or * something even more advanced than that, when the delivery status * becomes more than just done/deferred. */ msg_warn("corrupted queue file: %s", VSTREAM_PATH(src)); if (fchmod(vstream_fileno(src), MAIL_QUEUE_STAT_CORRUPT)) msg_fatal("%s: fchmod %s: %m", myname, VSTREAM_PATH(src)); /* * Restore privileges. */ if (saved_uid != var_owner_uid) set_eugid(saved_uid, saved_gid); return (DEL_STAT_DEFER); }
static void post_init(char *unused_name, char **unused_argv) { /* * Drop privileges most of the time. */ set_eugid(var_owner_uid, var_owner_gid); /* * No case folding needed: the recipient address is case folded. */ virtual_mailbox_maps = maps_create(VAR_VIRT_MAILBOX_MAPS, var_virt_mailbox_maps, DICT_FLAG_LOCK | DICT_FLAG_PARANOID); virtual_uid_maps = maps_create(VAR_VIRT_UID_MAPS, var_virt_uid_maps, DICT_FLAG_LOCK | DICT_FLAG_PARANOID); virtual_gid_maps = maps_create(VAR_VIRT_GID_MAPS, var_virt_gid_maps, DICT_FLAG_LOCK | DICT_FLAG_PARANOID); virtual_mbox_lock_mask = mbox_lock_mask(var_virt_mailbox_lock); }
static void post_init(char *unused_name, char **unused_argv) { /* * Drop privileges most of the time, and set up delivery restrictions. */ set_eugid(var_owner_uid, var_owner_gid); local_mask_init(); }
int open_as(const char *path, int flags, int mode, uid_t euid, gid_t egid) { uid_t saved_euid = geteuid(); gid_t saved_egid = getegid(); int fd; /* * Switch to the target user privileges. */ set_eugid(euid, egid); /* * Open that file. */ fd = open(path, flags, mode); /* * Restore saved privileges. */ set_eugid(saved_euid, saved_egid); return (fd); }
int stat_as(const char *path, struct stat * st, uid_t euid, gid_t egid) { uid_t saved_euid = geteuid(); gid_t saved_egid = getegid(); int status; /* * Switch to the target user privileges. */ set_eugid(euid, egid); /* * Stat that file. */ status = stat(path, st); /* * Restore saved privileges. */ set_eugid(saved_euid, saved_egid); return (status); }
int main(int argc, char **argv) { static VSTREAM *lock_fp; static VSTREAM *data_lock_fp; VSTRING *lock_path; VSTRING *data_lock_path; off_t inherited_limit; int debug_me = 0; int ch; int fd; int n; int test_lock = 0; VSTRING *why; WATCHDOG *watchdog; ARGV *import_env; /* * Fingerprint executables and core dumps. */ MAIL_VERSION_STAMP_ALLOCATE; /* * Initialize. */ umask(077); /* never fails! */ /* * Process environment options as early as we can. */ if (getenv(CONF_ENV_VERB)) msg_verbose = 1; if (getenv(CONF_ENV_DEBUG)) debug_me = 1; /* * Don't die when a process goes away unexpectedly. */ signal(SIGPIPE, SIG_IGN); /* * Strip and save the process name for diagnostics etc. */ var_procname = mystrdup(basename(argv[0])); /* * When running a child process, don't leak any open files that were * leaked to us by our own (privileged) parent process. Descriptors 0-2 * are taken care of after we have initialized error logging. * * Some systems such as AIX have a huge per-process open file limit. In * those cases, limit the search for potential file descriptor leaks to * just the first couple hundred. * * The Debian post-installation script passes an open file descriptor into * the master process and waits forever for someone to close it. Because * of this we have to close descriptors > 2, and pray that doing so does * not break things. */ closefrom(3); /* * Initialize logging and exit handler. */ msg_syslog_init(mail_task(var_procname), LOG_PID, LOG_FACILITY); /* * Check the Postfix library version as soon as we enable logging. */ MAIL_VERSION_CHECK; /* * The mail system must be run by the superuser so it can revoke * privileges for selected operations. That's right - it takes privileges * to toss privileges. */ if (getuid() != 0) msg_fatal("the master command is reserved for the superuser"); if (unsafe() != 0) msg_fatal("the master command must not run as a set-uid process"); /* * Process JCL. */ while ((ch = GETOPT(argc, argv, "c:Dde:tv")) > 0) { switch (ch) { case 'c': if (setenv(CONF_ENV_PATH, optarg, 1) < 0) msg_fatal("out of memory"); break; case 'd': master_detach = 0; break; case 'e': event_request_timer(master_exit_event, (char *) 0, atoi(optarg)); break; case 'D': debug_me = 1; break; case 't': test_lock = 1; break; case 'v': msg_verbose++; break; default: usage(argv[0]); /* NOTREACHED */ } } /* * This program takes no other arguments. */ if (argc > optind) usage(argv[0]); /* * If started from a terminal, get rid of any tty association. This also * means that all errors and warnings must go to the syslog daemon. */ if (master_detach) for (fd = 0; fd < 3; fd++) { (void) close(fd); if (open("/dev/null", O_RDWR, 0) != fd) msg_fatal("open /dev/null: %m"); } /* * Run in a separate process group, so that "postfix stop" can terminate * all MTA processes cleanly. Give up if we can't separate from our * parent process. We're not supposed to blow away the parent. */ if (debug_me == 0 && master_detach != 0 && setsid() == -1 && getsid(0) != getpid()) msg_fatal("unable to set session and process group ID: %m"); /* * Make some room for plumbing with file descriptors. XXX This breaks * when a service listens on many ports. In order to do this right we * must change the master-child interface so that descriptors do not need * to have fixed numbers. * * In a child we need two descriptors for the flow control pipe, one for * child->master status updates and at least one for listening. */ for (n = 0; n < 5; n++) { if (close_on_exec(dup(0), CLOSE_ON_EXEC) < 0) msg_fatal("dup(0): %m"); } /* * Final initializations. Unfortunately, we must read the global Postfix * configuration file after doing command-line processing, so that we get * consistent results when we SIGHUP the server to reload configuration * files. */ master_vars_init(); /* * In case of multi-protocol support. This needs to be done because * master does not invoke mail_params_init() (it was written before that * code existed). */ (void) inet_proto_init(VAR_INET_PROTOCOLS, var_inet_protocols); /* * Environment import filter, to enforce consistent behavior whether * Postfix is started by hand, or at system boot time. */ import_env = argv_split(var_import_environ, ", \t\r\n"); clean_env(import_env->argv); argv_free(import_env); if ((inherited_limit = get_file_limit()) < 0) set_file_limit(OFF_T_MAX); if (chdir(var_queue_dir)) msg_fatal("chdir %s: %m", var_queue_dir); /* * Lock down the master.pid file. In test mode, no file means that it * isn't locked. */ lock_path = vstring_alloc(10); data_lock_path = vstring_alloc(10); why = vstring_alloc(10); vstring_sprintf(lock_path, "%s/%s.pid", DEF_PID_DIR, var_procname); if (test_lock && access(vstring_str(lock_path), F_OK) < 0) exit(0); lock_fp = open_lock(vstring_str(lock_path), O_RDWR | O_CREAT, 0644, why); if (test_lock) exit(lock_fp ? 0 : 1); if (lock_fp == 0) msg_fatal("open lock file %s: %s", vstring_str(lock_path), vstring_str(why)); vstream_fprintf(lock_fp, "%*lu\n", (int) sizeof(unsigned long) * 4, (unsigned long) var_pid); if (vstream_fflush(lock_fp)) msg_fatal("cannot update lock file %s: %m", vstring_str(lock_path)); close_on_exec(vstream_fileno(lock_fp), CLOSE_ON_EXEC); /* * Lock down the Postfix-writable data directory. */ vstring_sprintf(data_lock_path, "%s/%s.lock", var_data_dir, var_procname); set_eugid(var_owner_uid, var_owner_gid); data_lock_fp = open_lock(vstring_str(data_lock_path), O_RDWR | O_CREAT, 0644, why); set_ugid(getuid(), getgid()); if (data_lock_fp == 0) msg_fatal("open lock file %s: %s", vstring_str(data_lock_path), vstring_str(why)); vstream_fprintf(data_lock_fp, "%*lu\n", (int) sizeof(unsigned long) * 4, (unsigned long) var_pid); if (vstream_fflush(data_lock_fp)) msg_fatal("cannot update lock file %s: %m", vstring_str(data_lock_path)); close_on_exec(vstream_fileno(data_lock_fp), CLOSE_ON_EXEC); /* * Clean up. */ vstring_free(why); vstring_free(lock_path); vstring_free(data_lock_path); /* * Optionally start the debugger on ourself. */ if (debug_me) debug_process(); /* * Finish initialization, last part. We must process configuration files * after processing command-line parameters, so that we get consistent * results when we SIGHUP the server to reload configuration files. */ master_config(); master_sigsetup(); master_flow_init(); msg_info("daemon started -- version %s, configuration %s", var_mail_version, var_config_dir); /* * Process events. The event handler will execute the read/write/timer * action routines. Whenever something has happened, see if we received * any signal in the mean time. Although the master process appears to do * multiple things at the same time, it really is all a single thread, so * that there are no concurrency conflicts within the master process. */ #define MASTER_WATCHDOG_TIME 1000 watchdog = watchdog_create(MASTER_WATCHDOG_TIME, (WATCHDOG_FN) 0, (char *) 0); for (;;) { #ifdef HAS_VOLATILE_LOCKS if (myflock(vstream_fileno(lock_fp), INTERNAL_LOCK, MYFLOCK_OP_EXCLUSIVE) < 0) msg_fatal("refresh exclusive lock: %m"); if (myflock(vstream_fileno(data_lock_fp), INTERNAL_LOCK, MYFLOCK_OP_EXCLUSIVE) < 0) msg_fatal("refresh exclusive lock: %m"); #endif watchdog_start(watchdog); /* same as trigger servers */ event_loop(MASTER_WATCHDOG_TIME / 2); if (master_gotsighup) { msg_info("reload -- version %s, configuration %s", var_mail_version, var_config_dir); master_gotsighup = 0; /* this first */ master_vars_init(); /* then this */ master_refresh(); /* then this */ } if (master_gotsigchld) { if (msg_verbose) msg_info("got sigchld"); master_gotsigchld = 0; /* this first */ master_reap_child(); /* then this */ } } }
static int deliver_mailbox_file(LOCAL_STATE state, USER_ATTR usr_attr) { const char *myname = "deliver_mailbox_file"; DSN_BUF *why = state.msg_attr.why; MBOX *mp; int mail_copy_status; int deliver_status; int copy_flags; long end; struct stat st; /* * Make verbose logging easier to understand. */ state.level++; if (msg_verbose) MSG_LOG_STATE(myname, state); /* * Don't deliver trace-only requests. */ if (DEL_REQ_TRACE_ONLY(state.request->flags)) { dsb_simple(why, "2.0.0", "delivers to mailbox"); return (sent(BOUNCE_FLAGS(state.request), SENT_ATTR(state.msg_attr))); } /* * Initialize. Assume the operation will fail. Set the delivered * attribute to reflect the final recipient. */ if (vstream_fseek(state.msg_attr.fp, state.msg_attr.offset, SEEK_SET) < 0) msg_fatal("seek message file %s: %m", VSTREAM_PATH(state.msg_attr.fp)); state.msg_attr.delivered = state.msg_attr.rcpt.address; mail_copy_status = MAIL_COPY_STAT_WRITE; /* * Lock the mailbox and open/create the mailbox file. * * Write the file as the recipient, so that file quota work. */ copy_flags = MAIL_COPY_MBOX; set_eugid(usr_attr.uid, usr_attr.gid); mp = mbox_open(usr_attr.mailbox, O_APPEND | O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR, &st, -1, -1, virtual_mbox_lock_mask, "4.2.0", why); if (mp != 0) { if (S_ISREG(st.st_mode) == 0) { vstream_fclose(mp->fp); msg_warn("recipient %s: destination %s is not a regular file", state.msg_attr.rcpt.address, usr_attr.mailbox); dsb_simple(why, "5.3.5", "mail system configuration error"); } else if (var_strict_mbox_owner && st.st_uid != usr_attr.uid) { vstream_fclose(mp->fp); dsb_simple(why, "4.2.0", "destination %s is not owned by recipient", usr_attr.mailbox); msg_warn("specify \"%s = no\" to ignore mailbox ownership mismatch", VAR_STRICT_MBOX_OWNER); } else { end = vstream_fseek(mp->fp, (off_t) 0, SEEK_END); mail_copy_status = mail_copy(COPY_ATTR(state.msg_attr), mp->fp, copy_flags, "\n", why); } mbox_release(mp); } set_eugid(var_owner_uid, var_owner_gid); /* * As the mail system, bounce, defer delivery, or report success. */ if (mail_copy_status & MAIL_COPY_STAT_CORRUPT) { deliver_status = DEL_STAT_DEFER; } else if (mail_copy_status != 0) { vstring_sprintf_prepend(why->reason, "delivery failed to mailbox %s: ", usr_attr.mailbox); deliver_status = (STR(why->status)[0] == '4' ? defer_append : bounce_append) (BOUNCE_FLAGS(state.request), BOUNCE_ATTR(state.msg_attr)); } else { dsb_simple(why, "2.0.0", "delivered to mailbox"); deliver_status = sent(BOUNCE_FLAGS(state.request), SENT_ATTR(state.msg_attr)); } return (deliver_status); }
static void drop_privileges(char *unused_name, char **unused_argv) { set_eugid(var_owner_uid, var_owner_gid); }
static void master_wakeup_timer_event(int unused_event, char *context) { const char *myname = "master_wakeup_timer_event"; MASTER_SERV *serv = (MASTER_SERV *) context; int status; static char wakeup = TRIGGER_REQ_WAKEUP; /* * Don't wakeup services whose automatic wakeup feature was turned off in * the mean time. */ if (serv->wakeup_time == 0) return; /* * Don't wake up services that are throttled. Find out what transport to * use. We can't block here so we choose a short timeout. */ #define BRIEFLY 1 if (MASTER_THROTTLED(serv) == 0) { if (msg_verbose) msg_info("%s: service %s", myname, serv->name); switch (serv->type) { case MASTER_SERV_TYPE_INET: status = inet_trigger(serv->name, &wakeup, sizeof(wakeup), BRIEFLY); break; case MASTER_SERV_TYPE_UNIX: status = LOCAL_TRIGGER(serv->name, &wakeup, sizeof(wakeup), BRIEFLY); break; #ifdef MASTER_SERV_TYPE_PASS case MASTER_SERV_TYPE_PASS: status = PASS_TRIGGER(serv->name, &wakeup, sizeof(wakeup), BRIEFLY); break; #endif /* * If someone compromises the postfix account then this must not * overwrite files outside the chroot jail. Countermeasures: * * - Limit the damage by accessing the FIFO as postfix not root. * * - Have fifo_trigger() call safe_open() so we won't follow * arbitrary hard/symlinks to files in/outside the chroot jail. * * - All non-chroot postfix-related files must be root owned (or * postfix check complains). * * - The postfix user and group ID must not be shared with other * applications (says the INSTALL documentation). * * Result of a discussion with Michael Tokarev, who received his * insights from Solar Designer, who tested Postfix with a kernel * module that is paranoid about open() calls. */ case MASTER_SERV_TYPE_FIFO: set_eugid(var_owner_uid, var_owner_gid); status = fifo_trigger(serv->name, &wakeup, sizeof(wakeup), BRIEFLY); set_ugid(getuid(), getgid()); break; default: msg_panic("%s: unknown service type: %d", myname, serv->type); } if (status < 0) msg_warn("%s: service %s(%s): %m", myname, serv->ext_name, serv->name); } /* * Schedule another wakeup event. */ event_request_timer(master_wakeup_timer_event, (char *) serv, serv->wakeup_time); }
static int deliver_mailbox_file(LOCAL_STATE state, USER_ATTR usr_attr) { const char *myname = "deliver_mailbox_file"; char *spool_dir; char *mailbox; DSN_BUF *why = state.msg_attr.why; MBOX *mp; int mail_copy_status; int deliver_status; int copy_flags; VSTRING *biff; long end; struct stat st; uid_t spool_uid; gid_t spool_gid; uid_t chown_uid; gid_t chown_gid; /* * Make verbose logging easier to understand. */ state.level++; if (msg_verbose) MSG_LOG_STATE(myname, state); /* * Don't deliver trace-only requests. */ if (DEL_REQ_TRACE_ONLY(state.request->flags)) { dsb_simple(why, "2.0.0", "delivers to mailbox"); return (sent(BOUNCE_FLAGS(state.request), SENT_ATTR(state.msg_attr))); } /* * Initialize. Assume the operation will fail. Set the delivered * attribute to reflect the final recipient. */ if (vstream_fseek(state.msg_attr.fp, state.msg_attr.offset, SEEK_SET) < 0) msg_fatal("seek message file %s: %m", VSTREAM_PATH(state.msg_attr.fp)); if (var_frozen_delivered == 0) state.msg_attr.delivered = state.msg_attr.rcpt.address; mail_copy_status = MAIL_COPY_STAT_WRITE; if (*var_home_mailbox) { spool_dir = 0; mailbox = concatenate(usr_attr.home, "/", var_home_mailbox, (char *) 0); } else { spool_dir = var_mail_spool_dir; mailbox = concatenate(spool_dir, "/", state.msg_attr.user, (char *) 0); } /* * Mailbox delivery with least privilege. As long as we do not use root * privileges this code may also work over NFS. * * If delivering to the recipient's home directory, perform all operations * (including file locking) as that user (Mike Muuss, Army Research * Laboratory, USA). * * If delivering to the mail spool directory, and the spool directory is * world-writable, deliver as the recipient; if the spool directory is * group-writable, use the recipient user id and the mail spool group id. * * Otherwise, use root privileges and chown the mailbox. */ if (spool_dir == 0 || stat(spool_dir, &st) < 0 || (st.st_mode & S_IWOTH) != 0) { spool_uid = usr_attr.uid; spool_gid = usr_attr.gid; } else if ((st.st_mode & S_IWGRP) != 0) { spool_uid = usr_attr.uid; spool_gid = st.st_gid; } else { spool_uid = 0; spool_gid = 0; } if (spool_uid == usr_attr.uid) { chown_uid = -1; chown_gid = -1; } else { chown_uid = usr_attr.uid; chown_gid = usr_attr.gid; } if (msg_verbose) msg_info("spool_uid/gid %ld/%ld chown_uid/gid %ld/%ld", (long) spool_uid, (long) spool_gid, (long) chown_uid, (long) chown_gid); /* * Lock the mailbox and open/create the mailbox file. Depending on the * type of locking used, we lock first or we open first. * * Write the file as the recipient, so that file quota work. */ copy_flags = MAIL_COPY_MBOX; if ((local_deliver_hdr_mask & DELIVER_HDR_FILE) == 0) copy_flags &= ~MAIL_COPY_DELIVERED; set_eugid(spool_uid, spool_gid); mp = mbox_open(mailbox, O_APPEND | O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR, &st, chown_uid, chown_gid, local_mbox_lock_mask, "5.2.0", why); if (mp != 0) { if (spool_uid != usr_attr.uid || spool_gid != usr_attr.gid) set_eugid(usr_attr.uid, usr_attr.gid); if (S_ISREG(st.st_mode) == 0) { vstream_fclose(mp->fp); dsb_simple(why, "5.2.0", "destination %s is not a regular file", mailbox); } else if (var_strict_mbox_owner && st.st_uid != usr_attr.uid) { vstream_fclose(mp->fp); dsb_simple(why, "4.2.0", "destination %s is not owned by recipient", mailbox); msg_warn("specify \"%s = no\" to ignore mailbox ownership mismatch", VAR_STRICT_MBOX_OWNER); } else { end = vstream_fseek(mp->fp, (off_t) 0, SEEK_END); mail_copy_status = mail_copy(COPY_ATTR(state.msg_attr), mp->fp, copy_flags, "\n", why); } if (spool_uid != usr_attr.uid || spool_gid != usr_attr.gid) set_eugid(spool_uid, spool_gid); mbox_release(mp); } set_eugid(var_owner_uid, var_owner_gid); /* * As the mail system, bounce, defer delivery, or report success. */ if (mail_copy_status & MAIL_COPY_STAT_CORRUPT) { deliver_status = DEL_STAT_DEFER; } else if (mail_copy_status != 0) { vstring_sprintf_prepend(why->reason, "cannot update mailbox %s for user %s. ", mailbox, state.msg_attr.user); deliver_status = (STR(why->status)[0] == '4' ? defer_append : bounce_append) (BOUNCE_FLAGS(state.request), BOUNCE_ATTR(state.msg_attr)); } else { dsb_simple(why, "2.0.0", "delivered to mailbox"); deliver_status = sent(BOUNCE_FLAGS(state.request), SENT_ATTR(state.msg_attr)); if (var_biff) { biff = vstring_alloc(100); vstring_sprintf(biff, "%s@%ld", usr_attr.logname, (long) end); biff_notify(STR(biff), VSTRING_LEN(biff) + 1); vstring_free(biff); } } /* * Clean up. */ myfree(mailbox); return (deliver_status); }
int deliver_file(LOCAL_STATE state, USER_ATTR usr_attr, char *path) { const char *myname = "deliver_file"; struct stat st; MBOX *mp; DSN_BUF *why = state.msg_attr.why; int mail_copy_status = MAIL_COPY_STAT_WRITE; int deliver_status; int copy_flags; /* * Make verbose logging easier to understand. */ state.level++; if (msg_verbose) MSG_LOG_STATE(myname, state); /* * DUPLICATE ELIMINATION * * Skip this file if it was already delivered to as this user. */ if (been_here(state.dup_filter, "file %ld %s", (long) usr_attr.uid, path)) return (0); /* * DELIVERY POLICY * * Do we allow delivery to files? */ if ((local_file_deliver_mask & state.msg_attr.exp_type) == 0) { dsb_simple(why, "5.7.1", "mail to file is restricted"); /* Account for possible owner- sender address override. */ return (bounce_workaround(state)); } /* * Don't deliver trace-only requests. */ if (DEL_REQ_TRACE_ONLY(state.request->flags)) { dsb_simple(why, "2.0.0", "delivers to file: %s", path); return (sent(BOUNCE_FLAGS(state.request), SENT_ATTR(state.msg_attr))); } /* * DELIVERY RIGHTS * * Use a default uid/gid when none are given. */ if (usr_attr.uid == 0 && (usr_attr.uid = var_default_uid) == 0) msg_panic("privileged default user id"); if (usr_attr.gid == 0 && (usr_attr.gid = var_default_gid) == 0) msg_panic("privileged default group id"); /* * If the name ends in /, use maildir-style delivery instead. */ if (path[strlen(path) - 1] == '/') return (deliver_maildir(state, usr_attr, path)); /* * Deliver. From here on, no early returns or we have a memory leak. */ if (msg_verbose) msg_info("deliver_file (%ld,%ld): %s", (long) usr_attr.uid, (long) usr_attr.gid, path); if (vstream_fseek(state.msg_attr.fp, state.msg_attr.offset, SEEK_SET) < 0) msg_fatal("seek queue file %s: %m", state.msg_attr.queue_id); /* * As the specified user, open or create the file, lock it, and append * the message. */ copy_flags = MAIL_COPY_MBOX; if ((local_deliver_hdr_mask & DELIVER_HDR_FILE) == 0) copy_flags &= ~MAIL_COPY_DELIVERED; set_eugid(usr_attr.uid, usr_attr.gid); mp = mbox_open(path, O_APPEND | O_CREAT | O_WRONLY, S_IRUSR | S_IWUSR, &st, -1, -1, local_mbox_lock_mask | MBOX_DOT_LOCK_MAY_FAIL, "5.2.0", why); if (mp != 0) { if (S_ISREG(st.st_mode) && st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) { vstream_fclose(mp->fp); dsb_simple(why, "5.7.1", "file is executable"); } else { mail_copy_status = mail_copy(COPY_ATTR(state.msg_attr), mp->fp, S_ISREG(st.st_mode) ? copy_flags : (copy_flags & ~MAIL_COPY_TOFILE), "\n", why); } mbox_release(mp); } set_eugid(var_owner_uid, var_owner_gid); /* * As the mail system, bounce, defer delivery, or report success. */ if (mail_copy_status & MAIL_COPY_STAT_CORRUPT) { deliver_status = DEL_STAT_DEFER; } else if (mail_copy_status != 0) { vstring_sprintf_prepend(why->reason, "cannot append message to file %s: ", path); if (STR(why->status)[0] == '4') deliver_status = defer_append(BOUNCE_FLAGS(state.request), BOUNCE_ATTR(state.msg_attr)); else /* Account for possible owner- sender address override. */ deliver_status = bounce_workaround(state); } else { dsb_simple(why, "2.0.0", "delivered to file: %s", path); deliver_status = sent(BOUNCE_FLAGS(state.request), SENT_ATTR(state.msg_attr)); } return (deliver_status); }
static void postmap(char *map_type, char *path_name, int postmap_flags, int open_flags, int dict_flags) { VSTREAM *NOCLOBBER source_fp; VSTRING *line_buffer; MKMAP *mkmap; int lineno; int last_line; char *key; char *value; struct stat st; mode_t saved_mask; /* * Initialize. */ line_buffer = vstring_alloc(100); if ((open_flags & O_TRUNC) == 0) { /* Incremental mode. */ source_fp = VSTREAM_IN; vstream_control(source_fp, CA_VSTREAM_CTL_PATH("stdin"), CA_VSTREAM_CTL_END); } else { /* Create database. */ if (strcmp(map_type, DICT_TYPE_PROXY) == 0) msg_fatal("can't create maps via the proxy service"); dict_flags |= DICT_FLAG_BULK_UPDATE; if ((source_fp = vstream_fopen(path_name, O_RDONLY, 0)) == 0) msg_fatal("open %s: %m", path_name); } if (fstat(vstream_fileno(source_fp), &st) < 0) msg_fatal("fstat %s: %m", path_name); /* * Turn off group/other read permissions as indicated in the source file. */ if ((postmap_flags & POSTMAP_FLAG_SAVE_PERM) && S_ISREG(st.st_mode)) saved_mask = umask(022 | (~st.st_mode & 077)); /* * If running as root, run as the owner of the source file, so that the * result shows proper ownership, and so that a bug in postmap does not * allow privilege escalation. */ if ((postmap_flags & POSTMAP_FLAG_AS_OWNER) && getuid() == 0 && (st.st_uid != geteuid() || st.st_gid != getegid())) set_eugid(st.st_uid, st.st_gid); /* * Open the database, optionally create it when it does not exist, * optionally truncate it when it does exist, and lock out any * spectators. */ mkmap = mkmap_open(map_type, path_name, open_flags, dict_flags); /* * And restore the umask, in case it matters. */ if ((postmap_flags & POSTMAP_FLAG_SAVE_PERM) && S_ISREG(st.st_mode)) umask(saved_mask); /* * Trap "exceptions" so that we can restart a bulk-mode update after a * recoverable error. */ for (;;) { if (dict_isjmp(mkmap->dict) != 0 && dict_setjmp(mkmap->dict) != 0 && vstream_fseek(source_fp, SEEK_SET, 0) < 0) msg_fatal("seek %s: %m", VSTREAM_PATH(source_fp)); /* * Add records to the database. */ last_line = 0; while (readllines(line_buffer, source_fp, &last_line, &lineno)) { /* * First some UTF-8 checks sans casefolding. */ if ((mkmap->dict->flags & DICT_FLAG_UTF8_ACTIVE) && !allascii(STR(line_buffer)) && !valid_utf8_string(STR(line_buffer), LEN(line_buffer))) { msg_warn("%s, line %d: non-UTF-8 input \"%s\"" " -- ignoring this line", VSTREAM_PATH(source_fp), lineno, STR(line_buffer)); continue; } /* * Split on the first whitespace character, then trim leading and * trailing whitespace from key and value. */ key = STR(line_buffer); value = key + strcspn(key, CHARS_SPACE); if (*value) *value++ = 0; while (ISSPACE(*value)) value++; trimblanks(key, 0)[0] = 0; trimblanks(value, 0)[0] = 0; /* * Enforce the "key whitespace value" format. Disallow missing * keys or missing values. */ if (*key == 0 || *value == 0) { msg_warn("%s, line %d: expected format: key whitespace value", VSTREAM_PATH(source_fp), lineno); continue; } if (key[strlen(key) - 1] == ':') msg_warn("%s, line %d: record is in \"key: value\" format; is this an alias file?", VSTREAM_PATH(source_fp), lineno); /* * Store the value under a case-insensitive key. */ mkmap_append(mkmap, key, value); if (mkmap->dict->error) msg_fatal("table %s:%s: write error: %m", mkmap->dict->type, mkmap->dict->name); } break; } /* * Close the mapping database, and release the lock. */ mkmap_close(mkmap); /* * Cleanup. We're about to terminate, but it is a good sanity check. */ vstring_free(line_buffer); if (source_fp != VSTREAM_IN) vstream_fclose(source_fp); }
void master_listen_init(MASTER_SERV *serv) { const char *myname = "master_listen_init"; char *end_point; int n; MAI_HOSTADDR_STR hostaddr; struct sockaddr *sa; /* * Find out what transport we should use, then create one or more * listener sockets. Make the listener sockets non-blocking, so that * child processes don't block in accept() when multiple processes are * selecting on the same socket and only one of them gets the connection. */ switch (serv->type) { /* * UNIX-domain or stream listener endpoints always come as singlets. */ case MASTER_SERV_TYPE_UNIX: set_eugid(var_owner_uid, var_owner_gid); serv->listen_fd[0] = LOCAL_LISTEN(serv->name, serv->max_proc > var_proc_limit ? serv->max_proc : var_proc_limit, NON_BLOCKING); close_on_exec(serv->listen_fd[0], CLOSE_ON_EXEC); set_ugid(getuid(), getgid()); break; /* * FIFO listener endpoints always come as singlets. */ case MASTER_SERV_TYPE_FIFO: set_eugid(var_owner_uid, var_owner_gid); serv->listen_fd[0] = fifo_listen(serv->name, 0622, NON_BLOCKING); close_on_exec(serv->listen_fd[0], CLOSE_ON_EXEC); set_ugid(getuid(), getgid()); break; /* * INET-domain listener endpoints can be wildcarded (the default) or * bound to specific interface addresses. * * With dual-stack IPv4/6 systems it does not matter, we have to specify * the addresses anyway, either explicit or wild-card. */ case MASTER_SERV_TYPE_INET: for (n = 0; n < serv->listen_fd_count; n++) { sa = SOCK_ADDR_PTR(MASTER_INET_ADDRLIST(serv)->addrs + n); SOCKADDR_TO_HOSTADDR(sa, SOCK_ADDR_LEN(sa), &hostaddr, (MAI_SERVPORT_STR *) 0, 0); end_point = concatenate(hostaddr.buf, ":", MASTER_INET_PORT(serv), (char *) 0); serv->listen_fd[n] = inet_listen(end_point, serv->max_proc > var_proc_limit ? serv->max_proc : var_proc_limit, NON_BLOCKING); close_on_exec(serv->listen_fd[n], CLOSE_ON_EXEC); myfree(end_point); } break; /* * Descriptor passing endpoints always come as singlets. */ #ifdef MASTER_SERV_TYPE_PASS case MASTER_SERV_TYPE_PASS: set_eugid(var_owner_uid, var_owner_gid); serv->listen_fd[0] = PASS_LISTEN(serv->name, serv->max_proc > var_proc_limit ? serv->max_proc : var_proc_limit, NON_BLOCKING); close_on_exec(serv->listen_fd[0], CLOSE_ON_EXEC); set_ugid(getuid(), getgid()); break; #endif default: msg_panic("%s: unknown service type: %d", myname, serv->type); } }
static void postmap(char *map_type, char *path_name, int postmap_flags, int open_flags, int dict_flags) { VSTREAM *source_fp; VSTRING *line_buffer; MKMAP *mkmap; int lineno; char *key; char *value; struct stat st; mode_t saved_mask; /* * Initialize. */ line_buffer = vstring_alloc(100); if ((open_flags & O_TRUNC) == 0) { source_fp = VSTREAM_IN; vstream_control(source_fp, VSTREAM_CTL_PATH, "stdin", VSTREAM_CTL_END); } else if (strcmp(map_type, DICT_TYPE_PROXY) == 0) { msg_fatal("can't create maps via the proxy service"); } else if ((source_fp = vstream_fopen(path_name, O_RDONLY, 0)) == 0) { msg_fatal("open %s: %m", path_name); } if (fstat(vstream_fileno(source_fp), &st) < 0) msg_fatal("fstat %s: %m", path_name); /* * Turn off group/other read permissions as indicated in the source file. */ if ((postmap_flags & POSTMAP_FLAG_SAVE_PERM) && S_ISREG(st.st_mode)) saved_mask = umask(022 | (~st.st_mode & 077)); /* * If running as root, run as the owner of the source file, so that the * result shows proper ownership, and so that a bug in postmap does not * allow privilege escalation. */ if ((postmap_flags & POSTMAP_FLAG_AS_OWNER) && getuid() == 0 && (st.st_uid != geteuid() || st.st_gid != getegid())) set_eugid(st.st_uid, st.st_gid); /* * Open the database, optionally create it when it does not exist, * optionally truncate it when it does exist, and lock out any * spectators. */ mkmap = mkmap_open(map_type, path_name, open_flags, dict_flags); /* * And restore the umask, in case it matters. */ if ((postmap_flags & POSTMAP_FLAG_SAVE_PERM) && S_ISREG(st.st_mode)) umask(saved_mask); /* * Add records to the database. */ lineno = 0; while (readlline(line_buffer, source_fp, &lineno)) { /* * Split on the first whitespace character, then trim leading and * trailing whitespace from key and value. */ key = STR(line_buffer); value = key + strcspn(key, " \t\r\n"); if (*value) *value++ = 0; while (ISSPACE(*value)) value++; trimblanks(key, 0)[0] = 0; trimblanks(value, 0)[0] = 0; /* * Enforce the "key whitespace value" format. Disallow missing keys * or missing values. */ if (*key == 0 || *value == 0) { msg_warn("%s, line %d: expected format: key whitespace value", VSTREAM_PATH(source_fp), lineno); continue; } if (key[strlen(key) - 1] == ':') msg_warn("%s, line %d: record is in \"key: value\" format; is this an alias file?", VSTREAM_PATH(source_fp), lineno); /* * Store the value under a case-insensitive key. */ mkmap_append(mkmap, key, value); if (mkmap->dict->error) msg_fatal("table %s:%s: write error: %m", mkmap->dict->type, mkmap->dict->name); } /* * Close the mapping database, and release the lock. */ mkmap_close(mkmap); /* * Cleanup. We're about to terminate, but it is a good sanity check. */ vstring_free(line_buffer); if (source_fp != VSTREAM_IN) vstream_fclose(source_fp); }
static void postalias(char *map_type, char *path_name, int postalias_flags, int open_flags, int dict_flags) { VSTREAM *NOCLOBBER source_fp; VSTRING *line_buffer; MKMAP *mkmap; int lineno; int last_line; VSTRING *key_buffer; VSTRING *value_buffer; TOK822 *tok_list; TOK822 *key_list; TOK822 *colon; TOK822 *value_list; struct stat st; mode_t saved_mask; /* * Initialize. */ line_buffer = vstring_alloc(100); key_buffer = vstring_alloc(100); value_buffer = vstring_alloc(100); if ((open_flags & O_TRUNC) == 0) { /* Incremental mode. */ source_fp = VSTREAM_IN; vstream_control(source_fp, CA_VSTREAM_CTL_PATH("stdin"), CA_VSTREAM_CTL_END); } else { /* Create database. */ if (strcmp(map_type, DICT_TYPE_PROXY) == 0) msg_fatal("can't create maps via the proxy service"); dict_flags |= DICT_FLAG_BULK_UPDATE; if ((source_fp = vstream_fopen(path_name, O_RDONLY, 0)) == 0) msg_fatal("open %s: %m", path_name); } if (fstat(vstream_fileno(source_fp), &st) < 0) msg_fatal("fstat %s: %m", path_name); /* * Turn off group/other read permissions as indicated in the source file. */ if ((postalias_flags & POSTALIAS_FLAG_SAVE_PERM) && S_ISREG(st.st_mode)) saved_mask = umask(022 | (~st.st_mode & 077)); /* * If running as root, run as the owner of the source file, so that the * result shows proper ownership, and so that a bug in postalias does not * allow privilege escalation. */ if ((postalias_flags & POSTALIAS_FLAG_AS_OWNER) && getuid() == 0 && (st.st_uid != geteuid() || st.st_gid != getegid())) set_eugid(st.st_uid, st.st_gid); /* * Open the database, create it when it does not exist, truncate it when * it does exist, and lock out any spectators. */ mkmap = mkmap_open(map_type, path_name, open_flags, dict_flags); /* * And restore the umask, in case it matters. */ if ((postalias_flags & POSTALIAS_FLAG_SAVE_PERM) && S_ISREG(st.st_mode)) umask(saved_mask); /* * Trap "exceptions" so that we can restart a bulk-mode update after a * recoverable error. */ for (;;) { if (dict_isjmp(mkmap->dict) != 0 && dict_setjmp(mkmap->dict) != 0 && vstream_fseek(source_fp, SEEK_SET, 0) < 0) msg_fatal("seek %s: %m", VSTREAM_PATH(source_fp)); /* * Add records to the database. */ last_line = 0; while (readllines(line_buffer, source_fp, &last_line, &lineno)) { /* * First some UTF-8 checks sans casefolding. */ if ((mkmap->dict->flags & DICT_FLAG_UTF8_ACTIVE) && !allascii(STR(line_buffer)) && !valid_utf8_string(STR(line_buffer), LEN(line_buffer))) { msg_warn("%s, line %d: non-UTF-8 input \"%s\"" " -- ignoring this line", VSTREAM_PATH(source_fp), lineno, STR(line_buffer)); continue; } /* * Tokenize the input, so that we do the right thing when a * quoted localpart contains special characters such as "@", ":" * and so on. */ if ((tok_list = tok822_scan(STR(line_buffer), (TOK822 **) 0)) == 0) continue; /* * Enforce the key:value format. Disallow missing keys, * multi-address keys, or missing values. In order to specify an * empty string or value, enclose it in double quotes. */ if ((colon = tok822_find_type(tok_list, ':')) == 0 || colon->prev == 0 || colon->next == 0 || tok822_rfind_type(colon, ',')) { msg_warn("%s, line %d: need name:value pair", VSTREAM_PATH(source_fp), lineno); tok822_free_tree(tok_list); continue; } /* * Key must be local. XXX We should use the Postfix rewriting and * resolving services to handle all address forms correctly. * However, we can't count on the mail system being up when the * alias database is being built, so we're guessing a bit. */ if (tok822_rfind_type(colon, '@') || tok822_rfind_type(colon, '%')) { msg_warn("%s, line %d: name must be local", VSTREAM_PATH(source_fp), lineno); tok822_free_tree(tok_list); continue; } /* * Split the input into key and value parts, and convert from * token representation back to string representation. Convert * the key to internal (unquoted) form, because the resolver * produces addresses in internal form. Convert the value to * external (quoted) form, because it will have to be re-parsed * upon lookup. Discard the token representation when done. */ key_list = tok_list; tok_list = 0; value_list = tok822_cut_after(colon); tok822_unlink(colon); tok822_free(colon); tok822_internalize(key_buffer, key_list, TOK822_STR_DEFL); tok822_free_tree(key_list); tok822_externalize(value_buffer, value_list, TOK822_STR_DEFL); tok822_free_tree(value_list); /* * Store the value under a case-insensitive key. */ mkmap_append(mkmap, STR(key_buffer), STR(value_buffer)); if (mkmap->dict->error) msg_fatal("table %s:%s: write error: %m", mkmap->dict->type, mkmap->dict->name); } break; } /* * Update or append sendmail and NIS signatures. */ if ((open_flags & O_TRUNC) == 0) mkmap->dict->flags |= DICT_FLAG_DUP_REPLACE; /* * Sendmail compatibility: add the @:@ signature to indicate that the * database is complete. This might be needed by NIS clients running * sendmail. */ mkmap_append(mkmap, "@", "@"); if (mkmap->dict->error) msg_fatal("table %s:%s: write error: %m", mkmap->dict->type, mkmap->dict->name); /* * NIS compatibility: add time and master info. Unlike other information, * this information MUST be written without a trailing null appended to * key or value. */ mkmap->dict->flags &= ~DICT_FLAG_TRY1NULL; mkmap->dict->flags |= DICT_FLAG_TRY0NULL; vstring_sprintf(value_buffer, "%010ld", (long) time((time_t *) 0)); #if (defined(HAS_NIS) || defined(HAS_NISPLUS)) mkmap->dict->flags &= ~DICT_FLAG_FOLD_FIX; mkmap_append(mkmap, "YP_LAST_MODIFIED", STR(value_buffer)); mkmap_append(mkmap, "YP_MASTER_NAME", var_myhostname); #endif /* * Close the alias database, and release the lock. */ mkmap_close(mkmap); /* * Cleanup. We're about to terminate, but it is a good sanity check. */ vstring_free(value_buffer); vstring_free(key_buffer); vstring_free(line_buffer); if (source_fp != VSTREAM_IN) vstream_fclose(source_fp); }
int deliver_maildir(LOCAL_STATE state, USER_ATTR usr_attr) { const char *myname = "deliver_maildir"; char *newdir; char *tmpdir; char *curdir; char *tmpfile; char *newfile; DSN_BUF *why = state.msg_attr.why; VSTRING *buf; VSTREAM *dst; int mail_copy_status; int deliver_status; int copy_flags; struct stat st; struct timeval starttime; GETTIMEOFDAY(&starttime); /* * Make verbose logging easier to understand. */ state.level++; if (msg_verbose) MSG_LOG_STATE(myname, state); /* * Don't deliver trace-only requests. */ if (DEL_REQ_TRACE_ONLY(state.request->flags)) { dsb_simple(why, "2.0.0", "delivers to maildir"); return (sent(BOUNCE_FLAGS(state.request), SENT_ATTR(state.msg_attr))); } /* * Initialize. Assume the operation will fail. Set the delivered * attribute to reflect the final recipient. */ if (vstream_fseek(state.msg_attr.fp, state.msg_attr.offset, SEEK_SET) < 0) msg_fatal("seek message file %s: %m", VSTREAM_PATH(state.msg_attr.fp)); state.msg_attr.delivered = state.msg_attr.rcpt.address; mail_copy_status = MAIL_COPY_STAT_WRITE; buf = vstring_alloc(100); copy_flags = MAIL_COPY_TOFILE | MAIL_COPY_RETURN_PATH | MAIL_COPY_DELIVERED | MAIL_COPY_ORIG_RCPT; newdir = concatenate(usr_attr.mailbox, "new/", (char *) 0); tmpdir = concatenate(usr_attr.mailbox, "tmp/", (char *) 0); curdir = concatenate(usr_attr.mailbox, "cur/", (char *) 0); /* * Create and write the file as the recipient, so that file quota work. * Create any missing directories on the fly. The file name is chosen * according to ftp://koobera.math.uic.edu/www/proto/maildir.html: * * "A unique name has three pieces, separated by dots. On the left is the * result of time(). On the right is the result of gethostname(). In the * middle is something that doesn't repeat within one second on a single * host. I fork a new process for each delivery, so I just use the * process ID. If you're delivering several messages from one process, * use starttime.pid_count.host, where starttime is the time that your * process started, and count is the number of messages you've * delivered." * * Well, that stopped working on fast machines, and on operating systems * that randomize process ID values. When creating a file in tmp/ we use * the process ID because it still is an exclusive resource. When moving * the file to new/ we use the device number and inode number. I do not * care if this breaks on a remote AFS file system, because people should * know better. * * On January 26, 2003, http://cr.yp.to/proto/maildir.html said: * * A unique name has three pieces, separated by dots. On the left is the * result of time() or the second counter from gettimeofday(). On the * right is the result of gethostname(). (To deal with invalid host * names, replace / with \057 and : with \072.) In the middle is a * delivery identifier, discussed below. * * [...] * * Modern delivery identifiers are created by concatenating enough of the * following strings to guarantee uniqueness: * * [...] * * In, where n is (in hexadecimal) the UNIX inode number of this file. * Unfortunately, inode numbers aren't always available through NFS. * * Vn, where n is (in hexadecimal) the UNIX device number of this file. * Unfortunately, device numbers aren't always available through NFS. * (Device numbers are also not helpful with the standard UNIX * filesystem: a maildir has to be within a single UNIX device for link() * and rename() to work.) * * Mn, where n is (in decimal) the microsecond counter from the same * gettimeofday() used for the left part of the unique name. * * Pn, where n is (in decimal) the process ID. * * [...] */ set_eugid(usr_attr.uid, usr_attr.gid); vstring_sprintf(buf, "%lu.P%d.%s", (unsigned long) starttime.tv_sec, var_pid, get_hostname()); tmpfile = concatenate(tmpdir, STR(buf), (char *) 0); newfile = 0; if ((dst = vstream_fopen(tmpfile, O_WRONLY | O_CREAT | O_EXCL, 0600)) == 0 && (errno != ENOENT || make_dirs(tmpdir, 0700) < 0 || (dst = vstream_fopen(tmpfile, O_WRONLY | O_CREAT | O_EXCL, 0600)) == 0)) { dsb_simple(why, mbox_dsn(errno, "4.2.0"), "create maildir file %s: %m", tmpfile); } else if (fstat(vstream_fileno(dst), &st) < 0) { /* * Coverity 200604: file descriptor leak in code that never executes. * Code replaced by msg_fatal(), as it is not worthwhile to continue * after an impossible error condition. */ msg_fatal("fstat %s: %m", tmpfile); } else { vstring_sprintf(buf, "%lu.V%lxI%lxM%lu.%s", (unsigned long) starttime.tv_sec, (unsigned long) st.st_dev, (unsigned long) st.st_ino, (unsigned long) starttime.tv_usec, get_hostname()); newfile = concatenate(newdir, STR(buf), (char *) 0); if ((mail_copy_status = mail_copy(COPY_ATTR(state.msg_attr), dst, copy_flags, "\n", why)) == 0) { if (sane_link(tmpfile, newfile) < 0 && (errno != ENOENT || (make_dirs(curdir, 0700), make_dirs(newdir, 0700)) < 0 || sane_link(tmpfile, newfile) < 0)) { dsb_simple(why, mbox_dsn(errno, "4.2.0"), "create maildir file %s: %m", newfile); mail_copy_status = MAIL_COPY_STAT_WRITE; } } if (unlink(tmpfile) < 0) msg_warn("remove %s: %m", tmpfile); } set_eugid(var_owner_uid, var_owner_gid); /* * The maildir location is controlled by the mail administrator. If * delivery fails, try again later. We would just bounce when the maildir * location possibly under user control. */ if (mail_copy_status & MAIL_COPY_STAT_CORRUPT) { deliver_status = DEL_STAT_DEFER; } else if (mail_copy_status != 0) { if (errno == EACCES) { msg_warn("maildir access problem for UID/GID=%lu/%lu: %s", (long) usr_attr.uid, (long) usr_attr.gid, STR(why->reason)); msg_warn("perhaps you need to create the maildirs in advance"); } vstring_sprintf_prepend(why->reason, "maildir delivery failed: "); deliver_status = (STR(why->status)[0] == '4' ? defer_append : bounce_append) (BOUNCE_FLAGS(state.request), BOUNCE_ATTR(state.msg_attr)); } else { dsb_simple(why, "2.0.0", "delivered to maildir"); deliver_status = sent(BOUNCE_FLAGS(state.request), SENT_ATTR(state.msg_attr)); } vstring_free(buf); myfree(newdir); myfree(tmpdir); myfree(curdir); myfree(tmpfile); if (newfile) myfree(newfile); return (deliver_status); }