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diff --git a/src/local/mailbox.c b/src/local/mailbox.c
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+/*++
+/* NAME
+/* mailbox 3
+/* SUMMARY
+/* mailbox delivery
+/* SYNOPSIS
+/* #include "local.h"
+/*
+/* int deliver_mailbox(state, usr_attr, statusp)
+/* LOCAL_STATE state;
+/* USER_ATTR usr_attr;
+/* int *statusp;
+/* DESCRIPTION
+/* deliver_mailbox() delivers to mailbox, with duplicate
+/* suppression. The default is direct mailbox delivery to
+/* /var/[spool/]mail/\fIuser\fR; when a \fIhome_mailbox\fR
+/* has been configured, mail is delivered to ~/$\fIhome_mailbox\fR;
+/* and when a \fImailbox_command\fR has been configured, the message
+/* is piped into the command instead.
+/*
+/* A zero result means that the named user was not found.
+/*
+/* Arguments:
+/* .IP state
+/* The attributes that specify the message, recipient and more.
+/* Attributes describing alias, include or forward expansion.
+/* A table with the results from expanding aliases or lists.
+/* .IP usr_attr
+/* Attributes describing user rights and environment.
+/* .IP statusp
+/* Delivery status: see below.
+/* DIAGNOSTICS
+/* The message delivery status is non-zero when delivery should be tried
+/* again.
+/* LICENSE
+/* .ad
+/* .fi
+/* The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/* Wietse Venema
+/* IBM T.J. Watson Research
+/* P.O. Box 704
+/* Yorktown Heights, NY 10598, USA
+/*
+/* Wietse Venema
+/* Google, Inc.
+/* 111 8th Avenue
+/* New York, NY 10011, USA
+/*--*/
+
+/* System library. */
+
+#include <sys_defs.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+
+/* Utility library. */
+
+#include <msg.h>
+#include <htable.h>
+#include <vstring.h>
+#include <vstream.h>
+#include <mymalloc.h>
+#include <stringops.h>
+#include <set_eugid.h>
+#include <warn_stat.h>
+
+/* Global library. */
+
+#include <mail_copy.h>
+#include <defer.h>
+#include <sent.h>
+#include <mypwd.h>
+#include <been_here.h>
+#include <mail_params.h>
+#include <deliver_pass.h>
+#include <mbox_open.h>
+#include <maps.h>
+#include <dsn_util.h>
+
+/* Application-specific. */
+
+#include "local.h"
+#include "biff_notify.h"
+
+#define YES 1
+#define NO 0
+
+/* deliver_mailbox_file - deliver to recipient mailbox */
+
+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;
+ off_t 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 we create it.
+ */
+ 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 {
+ if ((end = vstream_fseek(mp->fp, (off_t) 0, SEEK_END)) < 0)
+ msg_fatal("seek mailbox file %s: %m", mailbox);
+ 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);
+}
+
+/* deliver_mailbox - deliver to recipient mailbox */
+
+int deliver_mailbox(LOCAL_STATE state, USER_ATTR usr_attr, int *statusp)
+{
+ const char *myname = "deliver_mailbox";
+ int status;
+ struct mypasswd *mbox_pwd;
+ char *path;
+ static MAPS *transp_maps;
+ const char *map_transport;
+ static MAPS *cmd_maps;
+ const char *map_command;
+
+ /*
+ * Make verbose logging easier to understand.
+ */
+ state.level++;
+ if (msg_verbose)
+ MSG_LOG_STATE(myname, state);
+
+ /*
+ * DUPLICATE ELIMINATION
+ *
+ * Don't come here more than once, whether or not the recipient exists.
+ */
+ if (been_here(state.dup_filter, "mailbox %s", state.msg_attr.local))
+ return (YES);
+
+ /*
+ * Delegate mailbox delivery to another message transport.
+ */
+ if (*var_mbox_transp_maps && transp_maps == 0)
+ transp_maps = maps_create(VAR_MBOX_TRANSP_MAPS, var_mbox_transp_maps,
+ DICT_FLAG_LOCK | DICT_FLAG_NO_REGSUB
+ | DICT_FLAG_UTF8_REQUEST);
+ /* The -1 is a hint for the down-stream deliver_completed() function. */
+ if (transp_maps
+ && (map_transport = maps_find(transp_maps, state.msg_attr.user,
+ DICT_FLAG_NONE)) != 0) {
+ state.msg_attr.rcpt.offset = -1L;
+ *statusp = deliver_pass(MAIL_CLASS_PRIVATE, map_transport,
+ state.request, &state.msg_attr.rcpt);
+ return (YES);
+ } else if (transp_maps && transp_maps->error != 0) {
+ /* Details in the logfile. */
+ dsb_simple(state.msg_attr.why, "4.3.0", "table lookup failure");
+ *statusp = defer_append(BOUNCE_FLAGS(state.request),
+ BOUNCE_ATTR(state.msg_attr));
+ return (YES);
+ }
+ if (*var_mailbox_transport) {
+ state.msg_attr.rcpt.offset = -1L;
+ *statusp = deliver_pass(MAIL_CLASS_PRIVATE, var_mailbox_transport,
+ state.request, &state.msg_attr.rcpt);
+ return (YES);
+ }
+
+ /*
+ * Skip delivery when this recipient does not exist.
+ */
+ if ((errno = mypwnam_err(state.msg_attr.user, &mbox_pwd)) != 0) {
+ msg_warn("error looking up passwd info for %s: %m",
+ state.msg_attr.user);
+ dsb_simple(state.msg_attr.why, "4.0.0", "user lookup error");
+ *statusp = defer_append(BOUNCE_FLAGS(state.request),
+ BOUNCE_ATTR(state.msg_attr));
+ return (YES);
+ }
+ if (mbox_pwd == 0)
+ return (NO);
+
+ /*
+ * No early returns or we have a memory leak.
+ */
+
+ /*
+ * DELIVERY RIGHTS
+ *
+ * Use the rights of the recipient user.
+ */
+ SET_USER_ATTR(usr_attr, mbox_pwd, state.level);
+
+ /*
+ * Deliver to mailbox, maildir or to external command.
+ */
+#define LAST_CHAR(s) (s[strlen(s) - 1])
+
+ if (*var_mailbox_cmd_maps && cmd_maps == 0)
+ cmd_maps = maps_create(VAR_MAILBOX_CMD_MAPS, var_mailbox_cmd_maps,
+ DICT_FLAG_LOCK | DICT_FLAG_PARANOID
+ | DICT_FLAG_UTF8_REQUEST);
+
+ if (cmd_maps && (map_command = maps_find(cmd_maps, state.msg_attr.user,
+ DICT_FLAG_NONE)) != 0) {
+ status = deliver_command(state, usr_attr, map_command);
+ } else if (cmd_maps && cmd_maps->error != 0) {
+ /* Details in the logfile. */
+ dsb_simple(state.msg_attr.why, "4.3.0", "table lookup failure");
+ status = defer_append(BOUNCE_FLAGS(state.request),
+ BOUNCE_ATTR(state.msg_attr));
+ } else if (*var_mailbox_command) {
+ status = deliver_command(state, usr_attr, var_mailbox_command);
+ } else if (*var_home_mailbox && LAST_CHAR(var_home_mailbox) == '/') {
+ path = concatenate(usr_attr.home, "/", var_home_mailbox, (char *) 0);
+ status = deliver_maildir(state, usr_attr, path);
+ myfree(path);
+ } else if (*var_mail_spool_dir && LAST_CHAR(var_mail_spool_dir) == '/') {
+ path = concatenate(var_mail_spool_dir, state.msg_attr.user,
+ "/", (char *) 0);
+ status = deliver_maildir(state, usr_attr, path);
+ myfree(path);
+ } else
+ status = deliver_mailbox_file(state, usr_attr);
+
+ /*
+ * Cleanup.
+ */
+ mypwfree(mbox_pwd);
+ *statusp = status;
+ return (YES);
+}
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