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/* $OpenBSD: mfa.c,v 1.79 2013/07/19 16:02:00 eric Exp $ */
/*
* Copyright (c) 2008 Gilles Chehade <gilles@poolp.org>
* Copyright (c) 2008 Pierre-Yves Ritschard <pyr@openbsd.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/queue.h>
#include <sys/tree.h>
#include <sys/socket.h>
#include <err.h>
#include <errno.h>
#include <event.h>
#include <imsg.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "smtpd.h"
#include "log.h"
static void mfa_imsg(struct mproc *, struct imsg *);
static void mfa_shutdown(void);
static void mfa_sig_handler(int, short, void *);
static void
mfa_imsg(struct mproc *p, struct imsg *imsg)
{
struct sockaddr_storage local, remote;
struct mailaddr maddr;
struct msg m;
const char *line, *hostname;
uint64_t reqid;
int v;
if (p->proc == PROC_SMTP) {
switch (imsg->hdr.type) {
case IMSG_MFA_REQ_CONNECT:
m_msg(&m, imsg);
m_get_id(&m, &reqid);
m_get_sockaddr(&m, (struct sockaddr *)&local);
m_get_sockaddr(&m, (struct sockaddr *)&remote);
m_get_string(&m, &hostname);
m_end(&m);
mfa_filter_connect(reqid, (struct sockaddr *)&local,
(struct sockaddr *)&remote, hostname);
return;
case IMSG_MFA_REQ_HELO:
m_msg(&m, imsg);
m_get_id(&m, &reqid);
m_get_string(&m, &line);
m_end(&m);
mfa_filter_line(reqid, HOOK_HELO, line);
return;
case IMSG_MFA_REQ_MAIL:
m_msg(&m, imsg);
m_get_id(&m, &reqid);
m_get_mailaddr(&m, &maddr);
m_end(&m);
mfa_filter_mailaddr(reqid, HOOK_MAIL, &maddr);
return;
case IMSG_MFA_REQ_RCPT:
m_msg(&m, imsg);
m_get_id(&m, &reqid);
m_get_mailaddr(&m, &maddr);
m_end(&m);
mfa_filter_mailaddr(reqid, HOOK_RCPT, &maddr);
return;
case IMSG_MFA_REQ_DATA:
m_msg(&m, imsg);
m_get_id(&m, &reqid);
m_end(&m);
mfa_filter(reqid, HOOK_DATA);
return;
case IMSG_MFA_REQ_EOM:
m_msg(&m, imsg);
m_get_id(&m, &reqid);
m_end(&m);
mfa_filter(reqid, HOOK_EOM);
return;
case IMSG_MFA_SMTP_DATA:
m_msg(&m, imsg);
m_get_id(&m, &reqid);
m_get_string(&m, &line);
m_end(&m);
mfa_filter_data(reqid, line);
return;
case IMSG_MFA_EVENT_RSET:
m_msg(&m, imsg);
m_get_id(&m, &reqid);
m_end(&m);
mfa_filter_event(reqid, HOOK_RESET);
return;
case IMSG_MFA_EVENT_COMMIT:
m_msg(&m, imsg);
m_get_id(&m, &reqid);
m_end(&m);
mfa_filter_event(reqid, HOOK_COMMIT);
return;
case IMSG_MFA_EVENT_ROLLBACK:
m_msg(&m, imsg);
m_get_id(&m, &reqid);
m_end(&m);
mfa_filter_event(reqid, HOOK_ROLLBACK);
return;
case IMSG_MFA_EVENT_DISCONNECT:
m_msg(&m, imsg);
m_get_id(&m, &reqid);
m_end(&m);
mfa_filter_event(reqid, HOOK_DISCONNECT);
return;
}
}
if (p->proc == PROC_PARENT) {
switch (imsg->hdr.type) {
case IMSG_CONF_START:
return;
case IMSG_CONF_FILTER:
return;
case IMSG_CONF_END:
mfa_filter_init();
return;
case IMSG_CTL_VERBOSE:
m_msg(&m, imsg);
m_get_int(&m, &v);
m_end(&m);
log_verbose(v);
return;
case IMSG_CTL_PROFILE:
m_msg(&m, imsg);
m_get_int(&m, &v);
m_end(&m);
profiling = v;
return;
}
}
errx(1, "mfa_imsg: unexpected %s imsg", imsg_to_str(imsg->hdr.type));
}
static void
mfa_sig_handler(int sig, short event, void *p)
{
switch (sig) {
case SIGINT:
case SIGTERM:
mfa_shutdown();
break;
case SIGCHLD:
fatalx("unexpected SIGCHLD");
break;
default:
fatalx("mfa_sig_handler: unexpected signal");
}
}
static void
mfa_shutdown(void)
{
pid_t pid;
do {
pid = waitpid(WAIT_MYPGRP, NULL, 0);
} while (pid != -1 || (pid == -1 && errno == EINTR));
log_info("info: mail filter exiting");
_exit(0);
}
pid_t
mfa(void)
{
pid_t pid;
struct passwd *pw;
struct event ev_sigint;
struct event ev_sigterm;
struct event ev_sigchld;
switch (pid = fork()) {
case -1:
fatal("filter: cannot fork");
case 0:
break;
default:
return (pid);
}
mfa_filter_prepare();
purge_config(PURGE_EVERYTHING);
if ((pw = getpwnam(SMTPD_USER)) == NULL)
fatalx("unknown user " SMTPD_USER);
config_process(PROC_MFA);
if (chroot(PATH_CHROOT) == -1)
fatal("scheduler: chroot");
if (chdir("/") == -1)
fatal("scheduler: chdir(\"/\")");
if (setgroups(1, &pw->pw_gid) ||
setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) ||
setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid))
fatal("filter: cannot drop privileges");
imsg_callback = mfa_imsg;
event_init();
signal_set(&ev_sigint, SIGINT, mfa_sig_handler, NULL);
signal_set(&ev_sigterm, SIGTERM, mfa_sig_handler, NULL);
signal_set(&ev_sigchld, SIGCHLD, mfa_sig_handler, NULL);
signal_add(&ev_sigint, NULL);
signal_add(&ev_sigterm, NULL);
signal_add(&ev_sigchld, NULL);
signal(SIGPIPE, SIG_IGN);
signal(SIGHUP, SIG_IGN);
config_peer(PROC_PARENT);
config_peer(PROC_SMTP);
config_peer(PROC_CONTROL);
config_done();
mproc_disable(p_smtp);
if (event_dispatch() < 0)
fatal("event_dispatch");
mfa_shutdown();
return (0);
}
void
mfa_ready(void)
{
log_debug("debug: mfa ready");
mproc_enable(p_smtp);
}
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