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/*
* Copyright (c) 2004, Stefan Walter
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above
* copyright notice, this list of conditions and the
* following disclaimer.
* * Redistributions in binary form must reproduce the
* above copyright notice, this list of conditions and
* the following disclaimer in the documentation and/or
* other materials provided with the distribution.
* * The names of contributors to this software may not be
* used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
* THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
*
* CONTRIBUTORS
* Stefan Walter <stef@memberwebs.com>
* Andreas Steinmetz <ast@domdv.de>
* Rubio Vaughan <rubio@passim.net>
* Olivier Beyssac <ob@r14.freenix.org>
*/
#define _GNU_SOURCE
#include <sys/time.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <ctype.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <syslog.h>
#include <signal.h>
#include <errno.h>
#include <stdarg.h>
#include <pwd.h>
#include <time.h>
#include "usuals.h"
#ifdef LINUX_TRANSPARENT_PROXY
#include <linux/netfilter_ipv4.h>
#endif
#include "compat.h"
#include "sock_any.h"
#include "stringx.h"
#include "sppriv.h"
/* -----------------------------------------------------------------------
* STRUCTURES
*/
typedef struct spthread
{
pthread_t tid; /* Written to by the main thread */
int fd; /* The file descriptor or -1 */
}
spthread_t;
/* -----------------------------------------------------------------------
* DATA
*/
#define CRLF "\r\n"
#define SMTP_TOOLONG "500 Line too long" CRLF
#define SMTP_STARTBUSY "421 Server busy, too many connections" CRLF
#define SMTP_STARTFAILED "421 Local Error, cannot start thread" CRLF
#define SMTP_DATAINTERMED "354 Start mail input; end with <CRLF>.<CRLF>" CRLF
#define SMTP_FAILED "451 Local Error" CRLF
#define SMTP_NOTSUPP "502 Command not implemented" CRLF
#define SMTP_NOTAUTH "554 Insufficient authorization" CRLF
#define SMTP_OK "250 Ok" CRLF
#define SMTP_REJPREFIX "550 Content Rejected; "
#define SMTP_DATA "DATA" CRLF
#define SMTP_NOOP "NOOP" CRLF
#define SMTP_RSET "RSET" CRLF
#define SMTP_XCLIENT "XCLIENT ADDR=%s" CRLF
#define SMTP_BANNER "220 smtp.passthru" CRLF
#define SMTP_HELO_RSP "250 smtp.passthru" CRLF
#define SMTP_EHLO_RSP "250-smtp.passthru" CRLF
#define SMTP_FEAT_RSP "250 XFILTERED" CRLF
#define SMTP_DELIMS "\r\n\t :"
#define SMTP_MULTI_DELIMS " -"
#define ESMTP_PIPELINE "PIPELINING"
#define ESMTP_TLS "STARTTLS"
#define ESMTP_CHUNK "CHUNKING"
#define ESMTP_BINARY "BINARYMIME"
#define ESMTP_CHECK "CHECKPOINT"
#define ESMTP_XCLIENT "XCLIENT"
#define ESMTP_XEXCH50 "XEXCH50"
#define HELO_CMD "HELO"
#define EHLO_CMD "EHLO"
#define FROM_CMD "MAIL FROM"
#define TO_CMD "RCPT TO"
#define DATA_CMD "DATA"
#define RSET_CMD "RSET"
#define STARTTLS_CMD "STARTTLS"
#define BDAT_CMD "BDAT"
#define XCLIENT_CMD "XCLIENT"
#define XFORWARD_CMD "XFORWARD"
#define DATA_END_SIG "." CRLF
#define DATA_RSP "354"
#define OK_RSP "250"
#define START_RSP "220"
#define RCVD_HEADER "Received:"
/* The set of delimiters that can be present between config and value */
#define CFG_DELIMS ": \t"
/* Maximum length of the header argument */
#define MAX_HEADER_LENGTH 1024
/*
* asctime_r manpage: "stores the string in a user-supplied buffer of
* length at least 26". We'll need some more bytes to put timezone
* information behind
*/
#define MAX_DATE_LENGTH 64
#define LINE_TOO_LONG(l) ((l) >= (SP_LINE_LENGTH - 2))
/* -----------------------------------------------------------------------
* CONFIGURATION OPTIONS
*
* - Be sure that your configuration option needs to go into this
* file. More likely it'll go into clamsmtpd.c
* - When adding configuration options follow the instructions in
* clamsmtpd.c, except add option to spstate_t (sppriv.h) and parse in
* sp_parse_option (below)
*/
#define CFG_MAXTHREADS "MaxConnections"
#define CFG_TIMEOUT "TimeOut"
#define CFG_OUTADDR "OutAddress"
#define CFG_LISTENADDR "Listen"
#define CFG_TRANSPARENT "TransparentProxy"
#define CFG_DIRECTORY "TempDirectory"
#define CFG_KEEPALIVES "KeepAlives"
#define CFG_USER "User"
#define CFG_PIDFILE "PidFile"
#define CFG_XCLIENT "XClient"
/* -----------------------------------------------------------------------
* DEFAULT SETTINGS
*/
#define DEFAULT_SOCKET "10025"
#define DEFAULT_PORT 10025
#define DEFAULT_MAXTHREADS 64
#define DEFAULT_TIMEOUT 180
#define DEFAULT_KEEPALIVES 0
/* -----------------------------------------------------------------------
* GLOBALS
*/
spstate_t g_state; /* The state and configuration of the daemon */
unsigned int g_unique_id = 0x00100000; /* For connection ids */
pthread_mutex_t g_mutex; /* The main mutex */
pthread_mutexattr_t g_mtxattr;
/* -----------------------------------------------------------------------
* FORWARD DECLARATIONS
*/
static void on_quit(int signal);
static void drop_privileges();
static void pid_file(int write);
static void connection_loop(int sock);
static void* thread_main(void* arg);
static int smtp_passthru(spctx_t* ctx);
static int make_connections(spctx_t* ctx, int client);
static int read_server_response(spctx_t* ctx);
static int parse_config_file(const char* configfile);
static char* parse_address(char* line);
static char* parse_xforward(char* line, const char* part);
static const char* get_successful_rsp(const char* line, int* cont);
static void do_server_noop(spctx_t* ctx);
/* Used externally in some cases */
int sp_parse_option(const char* name, const char* option);
/* ----------------------------------------------------------------------------------
* BASIC RUN FUNCTIONALITY
*/
void sp_init(const char* name)
{
int r;
ASSERT(name);
memset(&g_state, 0, sizeof(g_state));
sp_message(NULL, LOG_DEBUG, "%s (%s)", name, VERSION);
/* Setup the defaults */
g_state.debug_level = -1;
g_state.max_threads = DEFAULT_MAXTHREADS;
g_state.timeout.tv_sec = DEFAULT_TIMEOUT;
g_state.keepalives = DEFAULT_KEEPALIVES;
g_state.directory = _PATH_TMP;
g_state.name = name;
/* We need the default to parse into a useable form, so we do this: */
r = sp_parse_option(CFG_LISTENADDR, DEFAULT_SOCKET);
ASSERT(r == 1);
/* Create the main mutex and condition variable */
if(pthread_mutexattr_init(&g_mtxattr) != 0 ||
#ifdef HAVE_ERR_MUTEX
pthread_mutexattr_settype(&g_mtxattr, MUTEX_TYPE) ||
#endif
pthread_mutex_init(&g_mutex, &g_mtxattr) != 0)
errx(1, "threading problem. can't create mutex or condition var");
}
int sp_run(const char* configfile, const char* pidfile, int dbg_level)
{
int sock;
int true = 1;
ASSERT(configfile);
ASSERT(g_state.name);
if(!(dbg_level == -1 || dbg_level <= LOG_DEBUG))
errx(2, "invalid debug log level (must be between 1 and 4)");
g_state.debug_level = dbg_level;
g_state.pidfile = pidfile;
/* Now parse the configuration file */
if(parse_config_file(configfile) == -1)
{
/*
* We used to do a check here before whether it was the default
* configuration file or not, but we can't do that any longer
* as it comes from the app. Usually lack of a configuration
* file will cause the following checks to fail
*/
warnx("configuration file not found: %s", configfile);
}
/* This option has no default, but is required ... */
if(g_state.outname == NULL && !g_state.transparent)
errx(2, "no " CFG_OUTADDR " specified.");
/* ... unless we're in transparent proxy mode */
else if(g_state.outname != NULL && g_state.transparent)
warnx("the " CFG_OUTADDR " option will be ignored when " CFG_TRANSPARENT " is enabled");
sp_messagex(NULL, LOG_DEBUG, "starting up (%s)...", VERSION);
/* Drop privileges before daemonizing */
drop_privileges();
/* When set to this we daemonize */
if(g_state.debug_level == -1)
{
/* Fork a daemon nicely here */
if(daemon(0, 0) == -1)
{
sp_message(NULL, LOG_ERR, "couldn't run as daemon");
exit(1);
}
sp_messagex(NULL, LOG_DEBUG, "running as a daemon");
g_state.daemonized = 1;
/* Open the system log */
openlog(g_state.name, 0, LOG_MAIL);
}
/* Handle some signals */
signal(SIGPIPE, SIG_IGN);
signal(SIGHUP, SIG_IGN);
signal(SIGINT, on_quit);
signal(SIGTERM, on_quit);
siginterrupt(SIGINT, 1);
siginterrupt(SIGTERM, 1);
/* Create the socket */
sock = socket(SANY_TYPE(g_state.listenaddr), SOCK_STREAM, 0);
if(sock < 0)
{
sp_message(NULL, LOG_CRIT, "couldn't open socket");
exit(1);
}
fcntl(sock, F_SETFD, fcntl(sock, F_GETFD, 0) | FD_CLOEXEC);
setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&true, sizeof(true));
/* Unlink the socket file if it exists */
if(SANY_TYPE(g_state.listenaddr) == AF_UNIX)
unlink(g_state.listenname);
if(bind(sock, &SANY_ADDR(g_state.listenaddr), SANY_LEN(g_state.listenaddr)) != 0)
{
sp_message(NULL, LOG_CRIT, "couldn't bind to address: %s", g_state.listenname);
exit(1);
}
sp_messagex(NULL, LOG_DEBUG, "created socket: %s", g_state.listenname);
/* Let 5 connections queue up */
if(listen(sock, 5) != 0)
{
sp_message(NULL, LOG_CRIT, "couldn't listen on socket");
exit(1);
}
pid_file(1);
sp_messagex(NULL, LOG_DEBUG, "accepting connections");
connection_loop(sock);
pid_file(0);
/* Our listen socket */
close(sock);
sp_messagex(NULL, LOG_DEBUG, "stopped processing");
return 0;
}
void sp_quit()
{
/* The handler sets the flag and this also interrupts io */
kill(getpid(), SIGTERM);
}
int sp_is_quit()
{
return g_state.quit ? 1 : 0;
}
void sp_done()
{
/* Close the mutex */
pthread_mutex_destroy(&g_mutex);
pthread_mutexattr_destroy(&g_mtxattr);
if(g_state._p)
free(g_state._p);
memset(&g_state, 0, sizeof(g_state));
}
static void on_quit(int signal)
{
g_state.quit = 1;
}
static void drop_privileges()
{
char* t;
struct passwd* pw;
uid_t uid;
if(g_state.user)
{
if(geteuid() != 0)
{
sp_messagex(NULL, LOG_WARNING, "must be started as root to switch to user: %s", g_state.user);
return;
}
uid = strtol(g_state.user, &t, 10);
if(!t[0]) /* successful parse */
pw = getpwuid(uid);
else /* must be a name */
pw = getpwnam(g_state.user);
if(pw == NULL)
errx(1, "couldn't look up user: %s", g_state.user);
if(setgid(pw->pw_gid) == -1 ||
setuid(pw->pw_uid) == -1)
err(1, "unable to switch to user: %s (uid %d, gid %d)", g_state.user, pw->pw_uid, pw->pw_gid);
/* A paranoia check */
if(setreuid(-1, 0) == 0)
err(1, "unable to completely drop privileges");
sp_messagex(NULL, LOG_DEBUG, "switched to user %s (uid %d, gid %d)", g_state.user, pw->pw_uid, pw->pw_gid);
}
if(geteuid() == 0)
sp_messagex(NULL, LOG_WARNING, "running as root is NOT recommended");
}
static void pid_file(int write)
{
if(!g_state.pidfile)
return;
if(write)
{
FILE* f = fopen(g_state.pidfile, "w");
if(f == NULL)
{
sp_message(NULL, LOG_ERR, "couldn't open pid file: %s", g_state.pidfile);
}
else
{
fprintf(f, "%d\n", (int)getpid());
if(ferror(f))
sp_message(NULL, LOG_ERR, "couldn't write to pid file: %s", g_state.pidfile);
if(fclose(f) == EOF)
sp_message(NULL, LOG_ERR, "couldn't write to pid file: %s", g_state.pidfile);
}
sp_messagex(NULL, LOG_DEBUG, "wrote pid file: %s", g_state.pidfile);
}
else
{
unlink(g_state.pidfile);
sp_messagex(NULL, LOG_DEBUG, "removed pid file: %s", g_state.pidfile);
}
}
static void connection_loop(int sock)
{
spthread_t* threads = NULL;
int fd, i, x, r;
/* Create the thread buffers */
threads = (spthread_t*)calloc(g_state.max_threads, sizeof(spthread_t));
if(!threads)
{
sp_messagex(NULL, LOG_CRIT, "out of memory");
return;
}
/* Now loop and accept the connections */
while(!sp_is_quit())
{
fd = accept(sock, NULL, NULL);
if(fd == -1)
{
switch(errno)
{
case EINTR:
case EAGAIN:
break;
case ECONNABORTED:
sp_message(NULL, LOG_ERR, "couldn't accept a connection");
break;
default:
sp_message(NULL, LOG_ERR, "couldn't accept a connection");
break;
};
if(sp_is_quit())
break;
continue;
}
/* Set timeouts on client */
if(setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &(g_state.timeout), sizeof(g_state.timeout)) < 0 ||
setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &(g_state.timeout), sizeof(g_state.timeout)) < 0)
sp_message(NULL, LOG_DEBUG, "couldn't set timeouts on incoming connection");
fcntl(fd, F_SETFD, fcntl(fd, F_GETFD, 0) | FD_CLOEXEC);
/* Look for thread and also clean up others */
for(i = 0; i < g_state.max_threads; i++)
{
/* Find a thread to run or clean up old threads */
if(threads[i].tid != 0)
{
sp_lock();
x = threads[i].fd;
sp_unlock();
if(x == -1)
{
sp_messagex(NULL, LOG_DEBUG, "cleaning up completed thread");
pthread_join(threads[i].tid, NULL);
threads[i].tid = 0;
}
#ifdef _DEBUG
else
{
/* For debugging connection problems: */
sp_messagex(NULL, LOG_DEBUG, "active connection thread: %x", (int)threads[i].tid);
}
#endif
}
/* Start a new thread if neccessary */
if(fd != -1 && threads[i].tid == 0)
{
threads[i].fd = fd;
r = pthread_create(&(threads[i].tid), NULL, thread_main,
(void*)(threads + i));
if(r != 0)
{
errno = r;
sp_message(NULL, LOG_ERR, "couldn't create thread");
write(fd, SMTP_STARTFAILED, KL(SMTP_STARTFAILED));
shutdown(fd, SHUT_RDWR);
close(fd);
fd = -1;
break;
}
sp_messagex(NULL, LOG_DEBUG, "created thread for connection");
fd = -1;
break;
}
}
/* Check to make sure we have a thread */
if(fd != -1)
{
sp_messagex(NULL, LOG_ERR, "too many connections open (max %d). sent busy response", g_state.max_threads);
write(fd, SMTP_STARTBUSY, KL(SMTP_STARTBUSY));
shutdown(fd, SHUT_RDWR);
close(fd);
fd = -1;
}
}
sp_messagex(NULL, LOG_DEBUG, "waiting for threads to quit");
/* Quit all threads here */
for(i = 0; i < g_state.max_threads; i++)
{
/* Clean up quit threads */
if(threads[i].tid != 0)
{
if(threads[i].fd != -1)
{
sp_lock();
fd = threads[i].fd;
threads[i].fd = -1;
sp_unlock();
shutdown(fd, SHUT_RDWR);
close(fd);
}
sp_messagex(NULL, LOG_DEBUG, "cleaning up completed thread");
pthread_join(threads[i].tid, NULL);
threads[i].tid = 0;
}
}
free(threads);
}
static spctx_t* init_thread(int fd)
{
spctx_t* ctx;
ctx = cb_new_context();
if(ctx)
{
memset(ctx, 0, sizeof(*ctx));
spio_init(&(ctx->server), "SERVER");
spio_init(&(ctx->client), "CLIENT");
sp_lock();
/* Assign a unique id to the connection */
ctx->id = g_unique_id++;
/* We don't care about wraps, but we don't want zero */
if(g_unique_id == 0)
g_unique_id++;
sp_unlock();
sp_messagex(ctx, LOG_DEBUG, "processing %d on thread %x", fd, (int)pthread_self());
/* Connect to the outgoing server ... */
if(make_connections(ctx, fd) == -1)
{
cb_del_context(ctx);
ctx = NULL;
}
}
return ctx;
}
static void cleanup_context(spctx_t* ctx)
{
ASSERT(ctx);
if(ctx->cachefile)
{
fclose(ctx->cachefile);
ctx->cachefile = NULL;
}
if(ctx->cachename[0])
{
unlink(ctx->cachename);
ctx->cachename[0] = 0;
}
if(ctx->recipients)
{
free(ctx->recipients);
ctx->recipients = NULL;
}
if(ctx->sender)
{
free(ctx->sender);
ctx->sender = NULL;
}
if(ctx->xforwardaddr)
{
free(ctx->xforwardaddr);
ctx->xforwardaddr = NULL;
}
if(ctx->xforwardhelo)
{
free(ctx->xforwardhelo);
ctx->xforwardhelo = NULL;
}
ctx->logline[0] = 0;
}
static void done_thread(spctx_t* ctx)
{
ASSERT(ctx);
spio_disconnect(ctx, &(ctx->client));
spio_disconnect(ctx, &(ctx->server));
/* Clean up file stuff */
cleanup_context(ctx);
cb_del_context(ctx);
}
static void* thread_main(void* arg)
{
spthread_t* thread = (spthread_t*)arg;
spctx_t* ctx = NULL;
int processing = 0;
int ret = 0;
int fd;
ASSERT(thread);
siginterrupt(SIGINT, 1);
siginterrupt(SIGTERM, 1);
sp_lock();
/* Get the client socket */
fd = thread->fd;
sp_unlock();
/* Sometimes we get to this point and then quit is noted */
if(sp_is_quit() || (ctx = init_thread(fd)) == NULL)
{
/* Special case. We don't have a context so clean up descriptor */
close(fd);
/* new_context() should have already logged reason */
RETURN(-1);
}
/* call the processor */
processing = 1;
ret = smtp_passthru(ctx);
cleanup:
if(ctx)
{
/* Let the client know about fatal errors */
if(!processing && ret == -1 && spio_valid(&(ctx->client)))
spio_write_data(ctx, &(ctx->client), SMTP_STARTFAILED);
done_thread(ctx);
}
/* mark this as done */
sp_lock();
thread->fd = -1;
sp_unlock();
return (void*)(ret == 0 ? 0 : 1);
}
static int make_connections(spctx_t* ctx, int client)
{
struct sockaddr_any peeraddr;
struct sockaddr_any addr;
struct sockaddr_any* outaddr;
char buf[MAXPATHLEN];
const char* outname;
ASSERT(client != -1);
/* Setup the incoming connection. This also fills in peeraddr for us */
spio_attach(ctx, &(ctx->client), client, &peeraddr);
sp_messagex(ctx, LOG_INFO, "accepted connection from: %s", ctx->client.peername);
/* Create the server connection address */
outaddr = &(g_state.outaddr);
outname = g_state.outname;
/* For transparent proxying we have to discover the address to connect to */
if(g_state.transparent)
{
memset(&addr, 0, sizeof(addr));
SANY_LEN(addr) = sizeof(addr);
#ifdef LINUX_TRANSPARENT_PROXY
if(getsockopt(ctx->client.fd, SOL_IP, SO_ORIGINAL_DST, &SANY_ADDR(addr), &SANY_LEN(addr)) == -1)
#else
if(getsockname(ctx->client.fd, &SANY_ADDR(addr), &SANY_LEN(addr)) == -1)
#endif
{
sp_message(ctx, LOG_ERR, "couldn't get source address for transparent proxying");
return -1;
}
/* Check address types */
if(sock_any_cmp(&addr, &peeraddr, SANY_OPT_NOPORT) == 0)
{
sp_messagex(ctx, LOG_ERR, "loop detected in transparent proxying");
return -1;
}
outaddr = &addr;
}
/* Check for loopback option */
else if(SANY_TYPE(*outaddr) == AF_INET &&
outaddr->s.in.sin_addr.s_addr == 0)
{
/* Use the incoming IP as the default */
memcpy(&addr, &(g_state.outaddr), sizeof(addr));
memcpy(&(addr.s.in.sin_addr), &(peeraddr.s.in.sin_addr), sizeof(addr.s.in.sin_addr));
outaddr = &addr;
}
#ifdef HAVE_INET6
/* IPv6 loopback? */
else if(SANY_TYPE(*outaddr) == AF_INET6 &&
outaddr->s.in.in6.sin_addr.s_addr == 0)
{
/* Use the incoming IP as the default */
memcpy(&addr, &(g_state.outaddr), sizeof(addr));
memcpy(&(addr.s.in.sin6_addr), &(peeraddr.s.in.sin6_addr), sizeof(addr.s.in.sin6_addr));
outaddr = &addr;
}
#endif
/* Not transparent proxy or loopback */
else
{
/* Resolve any DNS name again */
if(sock_any_pton(g_state.outname, &addr, SANY_OPT_DEFPORT(25)) != -1)
memcpy(&(g_state.outaddr), &addr, sizeof(g_state.outaddr));
else
sp_messagex(ctx, LOG_WARNING, "couldn't resolve " CFG_OUTADDR ": %s", g_state.outname);
}
/* Reparse name if needed */
if(outaddr != &(g_state.outaddr))
{
if(sock_any_ntop(outaddr, buf, MAXPATHLEN, 0) != -1)
outname = buf;
else
outname = "unknown";
}
/* Connect to the server */
if(spio_connect(ctx, &(ctx->server), outaddr, outname) == -1)
return -1;
return 0;
}
/* ----------------------------------------------------------------------------------
* SMTP HANDLING
*/
static int smtp_passthru(spctx_t* ctx)
{
char* t;
const char* p;
int r, cont, ret = 0;
unsigned int mask;
int neterror = 0;
int first_rsp = 1; /* The first 220 response from server to be filtered */
int filter_host = 0; /* Next response is 250 hostname, which we change */
/* XCLIENT is for use in access control */
int xclient_sup = 0; /* Is XCLIENT supported? */
int xclient_sent = 0; /* Have we sent an XCLIENT command? */
ASSERT(spio_valid(&(ctx->client)) &&
spio_valid(&(ctx->server)));
#define C_LINE ctx->client.line
#define S_LINE ctx->server.line
while(!sp_is_quit())
{
mask = spio_select(ctx, &(ctx->client), &(ctx->server), NULL);
if(mask == ~0)
{
neterror = 1;
RETURN(-1);
}
/* Client has data available, read a line and process */
if(mask & 1)
{
if((r = spio_read_line(ctx, &(ctx->client), SPIO_DISCARD)) == -1)
RETURN(-1);
/* Client disconnected, we're done */
if(r == 0)
RETURN(0);
/* We don't let clients send really long lines */
if(LINE_TOO_LONG(r))
{
if(spio_write_data(ctx, &(ctx->client), SMTP_TOOLONG) == -1)
RETURN(-1);
continue;
}
/* Only valid after EHLO or HELO commands */
filter_host = 0;
/*
* At this point we may want to send our XCLIENT. This is a per
* connection command.
*/
if(xclient_sup && !xclient_sent && g_state.xclient)
{
sp_messagex(ctx, LOG_DEBUG, "sending XCLIENT");
if(spio_write_dataf(ctx, &(ctx->server), SMTP_XCLIENT, ctx->client.peername) == -1)
RETURN(-1);
if(read_server_response(ctx) == -1)
RETURN(-1);
if(!get_successful_rsp(S_LINE, NULL))
sp_messagex(ctx, LOG_WARNING, "server didn't accept XCLIENT");
xclient_sent = 1;
}
/* Handle the DATA section via our AV checker */
if(is_first_word(C_LINE, DATA_CMD, KL(DATA_CMD)))
{
/* Send back the intermediate response to the client */
if(spio_write_data(ctx, &(ctx->client), SMTP_DATAINTERMED) == -1)
RETURN(-1);
/*
* Now go into scan mode. This also handles the eventual
* sending of the data to the server, making the av check
* transparent
*/
if(cb_check_data(ctx) == -1)
RETURN(-1);
/* Print the log out for this email */
sp_messagex(ctx, LOG_INFO, "%s", ctx->logline);
/* Done with that email */
cleanup_context(ctx);
/* Command handled */
continue;
}
/*
* We need our response to HELO and EHLO to be modified in order
* to prevent complaints about mail loops
*/
else if(is_first_word(C_LINE, EHLO_CMD, KL(EHLO_CMD)))
{
/* EHLO can have multline responses so we set a flag */
filter_host = 1;
}
/*
* We always support XCLIENT on a HELO type connection. We do this
* for security reasons, so that a client can't get around filtering
* by backing up one on the protocol.
*/
else if(is_first_word(C_LINE, HELO_CMD, KL(HELO_CMD)))
{
sp_messagex(ctx, LOG_DEBUG, "XCLIENT support assumed");
xclient_sup = 1;
/* Filter host as with EHLO above */
filter_host = 1;
}
/*
* We don't like these commands. Filter them out. We should have
* filtered out their service extensions earlier in the EHLO response.
* This is just for errant clients.
*/
else if(is_first_word(C_LINE, STARTTLS_CMD, KL(STARTTLS_CMD)) ||
is_first_word(C_LINE, BDAT_CMD, KL(BDAT_CMD)))
{
sp_messagex(ctx, LOG_DEBUG, "ESMTP feature not supported");
if(spio_write_data(ctx, &(ctx->client), SMTP_NOTSUPP) == -1)
RETURN(-1);
/* Command handled */
continue;
}
/*
* For security reasons we're not about to forward any XCLIENTs
* from our client through. This could lead to a client using our
* privileged IP address to change an audit trail or relay etc...
*/
else if(is_first_word(C_LINE, XCLIENT_CMD, KL(XCLIENT_CMD)))
{
sp_messagex(ctx, LOG_WARNING, "client attempted use of privileged XCLIENT feature");
if(spio_write_data(ctx, &(ctx->client), SMTP_NOTAUTH) == -1)
RETURN(-1);
/* Command handled */
continue;
}
/* All other commands just get passed through to server */
if(spio_write_data(ctx, &(ctx->server), C_LINE) == -1)
RETURN(-1);
continue;
}
/* Server has data available, read a line and forward */
if(mask & 2)
{
if((r = spio_read_line(ctx, &(ctx->server), SPIO_DISCARD)) == -1)
RETURN(-1);
if(r == 0)
RETURN(0);
if(LINE_TOO_LONG(r))
sp_messagex(ctx, LOG_WARNING, "SMTP response line too long. discarded extra");
/*
* We intercept the first response we get from the server.
* This allows us to change header so that it doesn't look
* to the client server that we're in a wierd loop.
*
* In different situations using the local hostname or
* 'localhost' don't work because the receiving mail server
* expects one of those to be its own name. We use 'clamsmtp'
* instead. No properly configured server would have this
* as their domain name, and RFC 2821 allows us to use
* an arbitrary but identifying string.
*/
if(first_rsp)
{
first_rsp = 0;
if(is_first_word(S_LINE, START_RSP, KL(START_RSP)))
{
sp_messagex(ctx, LOG_DEBUG, "intercepting initial response");
if(spio_write_data(ctx, &(ctx->client), SMTP_BANNER) == -1)
RETURN(-1);
/* Command handled */
continue;
}
}
if((p = get_successful_rsp(S_LINE, &cont)) != NULL)
{
/*
* Certain mail servers (Postfix 1.x in particular) do a loop check
* on the 250 response after a EHLO or HELO. This is where we
* filter that to prevent loopback errors.
*/
if(filter_host)
{
/* Can have multi-line responses, and we want to be
* sure to only replace the first one. */
filter_host = 0;
sp_messagex(ctx, LOG_DEBUG, "intercepting host response");
if(spio_write_data(ctx, &(ctx->client),
cont ? SMTP_EHLO_RSP : SMTP_HELO_RSP) == -1)
RETURN(-1);
/* A new email so cleanup */
cleanup_context(ctx);
continue;
}
/*
* Filter out any EHLO responses that we can't or don't want
* to support. For example pipelining or TLS.
*/
if(is_first_word(C_LINE, EHLO_CMD, KL(EHLO_CMD)))
{
/*
* On ESMTP connections we let the server tell us whether it
* wants XCLIENTs or not. (In contrast to old SMTP above).
*/
if(is_first_word(p, ESMTP_XCLIENT, KL(ESMTP_XCLIENT)))
{
sp_messagex(ctx, LOG_DEBUG, "XCLIENT supported");
xclient_sup = 1;
}
if(is_first_word(p, ESMTP_PIPELINE, KL(ESMTP_PIPELINE)) ||
is_first_word(p, ESMTP_TLS, KL(ESMTP_TLS)) ||
is_first_word(p, ESMTP_CHUNK, KL(ESMTP_CHUNK)) ||
is_first_word(p, ESMTP_BINARY, KL(ESMTP_BINARY)) ||
is_first_word(p, ESMTP_CHECK, KL(ESMTP_CHECK)) ||
is_first_word(p, ESMTP_XCLIENT, KL(ESMTP_XCLIENT)) ||
is_first_word(p, ESMTP_XEXCH50, KL(ESMTP_XEXCH50)))
{
sp_messagex(ctx, LOG_DEBUG, "filtered ESMTP feature: %s", trim_space((char*)p));
/*
* If this is the last line in the EHLO response we need
* to replace it with something else
*/
if(!cont)
{
if(spio_write_data(ctx, &(ctx->client), SMTP_FEAT_RSP) == -1)
RETURN(-1);
}
continue;
}
}
/* MAIL FROM (that the server accepted) */
if((r = check_first_word(C_LINE, FROM_CMD, KL(FROM_CMD), SMTP_DELIMS)) > 0)
{
t = parse_address(C_LINE + r);
sp_add_log(ctx, "from=", t);
/* Make note of the sender for later */
ctx->sender = (char*)reallocf(ctx->sender, strlen(t) + 1);
if(ctx->sender)
strcpy(ctx->sender, t);
}
/* RCPT TO (that the server accepted) */
else if((r = check_first_word(C_LINE, TO_CMD, KL(TO_CMD), SMTP_DELIMS)) > 0)
{
t = parse_address(C_LINE + r);
sp_add_log(ctx, "to=", t);
/* Make note of the recipient for later */
r = ctx->recipients ? strlen(ctx->recipients) : 0;
ctx->recipients = (char*)reallocf(ctx->recipients, r + strlen(t) + 2);
if(ctx->recipients)
{
/* Recipients are separated by lines */
if(r != 0)
strcat(ctx->recipients, "\n");
else
ctx->recipients[0] = 0;
strcat(ctx->recipients, t);
}
}
/*
* If the client sends an XFORWARD, and the server accepted it,
* we store address for use in our forked process environment
* variables (see sp_setup_forked).
*/
else if(is_first_word(C_LINE, XFORWARD_CMD, KL(XFORWARD_CMD)))
{
if((t = parse_xforward (C_LINE + KL(XFORWARD_CMD), "ADDR")))
{
ctx->xforwardaddr = (char*)reallocf(ctx->xforwardaddr, strlen(t) + 1);
if(ctx->xforwardaddr)
strcpy(ctx->xforwardaddr, t);
}
if((t = parse_xforward (C_LINE + KL(XFORWARD_CMD), "HELO")))
{
ctx->xforwardhelo = (char*)reallocf(ctx->xforwardhelo, strlen(t) + 1);
if(ctx->xforwardhelo)
strcpy(ctx->xforwardhelo, t);
}
}
/* RSET */
else if(is_first_word(C_LINE, RSET_CMD, KL(RSET_CMD)))
{
cleanup_context(ctx);
}
}
if(spio_write_data(ctx, &(ctx->client), S_LINE) == -1)
RETURN(-1);
continue;
}
}
cleanup:
if(!neterror && ret == -1 && spio_valid(&(ctx->client)))
spio_write_data(ctx, &(ctx->client), SMTP_FAILED);
return ret;
}
/* -----------------------------------------------------------------------------
* SMTP PASSTHRU FUNCTIONS FOR DATA CHECK
*/
static char* parse_address(char* line)
{
char* t;
line = trim_start(line);
/*
* We parse out emails in the form of <blah@blah.com>
* as well as accept other addresses.
*/
if(strncmp(line, "<>", 2) == 0)
return("<>");
if(line[0] == '<')
{
if((t = strchr(line, '>')) != NULL)
{
*t = 0;
line++;
return line;
}
}
return trim_end(line);
}
static char* parse_xforward(char* line, const char* part)
{
char* t;
char* e;
t = strcasestr(line, part);
if(!t)
return NULL;
/* equals sign and surrounding */
t = trim_start(t + strlen(part));
if(*t != '=')
return NULL;
t = trim_start(t + 1);
if(!*t)
return NULL;
/* Find the end of the thingy */
if(*t == '[')
{
t++;
e = strchr(t, ']');
}
else
{
e = t + strcspn(t, " \t");
}
if(!e)
return NULL;
*e = 0;
return t;
}
static const char* get_successful_rsp(const char* line, int* cont)
{
/*
* We check for both '250 xxx' type replies
* and the continued response '250-xxxx' type
*/
line = trim_start(line);
if(line[0] == '2' && isdigit(line[1]) && isdigit(line[2]) &&
(line[3] == ' ' || line[3] == '-'))
{
if(cont)
*cont = (line[3] == '-');
return line + 4;
}
return NULL;
}
void sp_add_log(spctx_t* ctx, char* prefix, char* line)
{
char* t = ctx->logline;
int l = strlen(t);
int x;
ASSERT(l <= SP_LOG_LINE_LEN);
/* Add up necessary lengths */
x = 2 + strlen(prefix) + strlen(line) + 1;
if(l + x >= SP_LOG_LINE_LEN)
l = SP_LOG_LINE_LEN - x;
t += l;
l = SP_LOG_LINE_LEN - l;
*t = 0;
if(ctx->logline[0] != 0)
strlcat(t, ", ", l);
strlcat(t, prefix, l);
/* Skip initial white space */
line = trim_start(line);
strlcat(t, line, l);
/* Skip later white space */
trim_end(t);
}
int sp_read_data(spctx_t* ctx, const char** data)
{
int r;
ASSERT(ctx);
ASSERT(data);
*data = NULL;
switch(r = spio_read_line(ctx, &(ctx->client), SPIO_QUIET))
{
case 0:
sp_messagex(ctx, LOG_ERR, "unexpected end of data from client");
return -1;
case -1:
/* Message already printed */
return -1;
};
if(g_state.keepalives > 0)
{
/*
* During this time we're just reading from the client. If we haven't
* had any interaction with the server recently then send something
* to let it know we're still around.
*/
if((ctx->server.last_action + g_state.keepalives) < time(NULL))
do_server_noop(ctx);
}
if(ctx->_crlf && strcmp(ctx->client.line, DATA_END_SIG) == 0)
return 0;
/* Check if this line ended with a CRLF */
ctx->_crlf = (strcmp(CRLF, ctx->client.line + (r - KL(CRLF))) == 0);
*data = ctx->client.line;
return r;
}
int sp_write_data(spctx_t* ctx, const char* buf, int len)
{
int r = 0;
ASSERT(ctx);
/* When a null buffer close the cache file */
if(!buf)
{
if(ctx->cachefile)
{
if(fclose(ctx->cachefile) == EOF)
{
sp_message(ctx, LOG_ERR, "couldn't write to cache file: %s", ctx->cachename);
r = -1;
}
ctx->cachefile = NULL;
}
return r;
}
/* Make sure we have a file open */
if(!ctx->cachefile)
{
int tfd;
/* Make sure afore mentioned file is gone */
if(ctx->cachename[0])
unlink(ctx->cachename);
snprintf(ctx->cachename, MAXPATHLEN, "%s/%s.XXXXXX",
g_state.directory, g_state.name);
if((tfd = mkstemp(ctx->cachename)) == -1 ||
(ctx->cachefile = fdopen(tfd, "w")) == NULL)
{
if(tfd != -1)
close(tfd);
sp_message(ctx, LOG_ERR, "couldn't open cache file");
return -1;
}
fcntl(tfd, F_SETFD, fcntl(tfd, F_GETFD, 0) | FD_CLOEXEC);
sp_messagex(ctx, LOG_DEBUG, "created cache file: %s", ctx->cachename);
}
fwrite(buf, 1, len, ctx->cachefile);
if(ferror(ctx->cachefile))
{
sp_message(ctx, LOG_ERR, "couldn't write to cache file: %s", ctx->cachename);
return -1;
}
return len;
}
int sp_cache_data(spctx_t* ctx)
{
int r, count = 0;
const char* data;
while((r = sp_read_data(ctx, &data)) != 0)
{
if(r < 0)
return -1; /* Message already printed */
count += r;
if((r = sp_write_data(ctx, data, r)) < 0)
return -1; /* Message already printed */
}
/* End the caching */
if(sp_write_data(ctx, NULL, 0) < 0)
return -1;
sp_messagex(ctx, LOG_DEBUG, "wrote %d bytes to cache", count);
return count;
}
/* Important: |date| should be at least MAX_DATE_LENGTH long */
static void make_date(spctx_t* ctx, char* date)
{
size_t date_len;
struct tm t2;
time_t t;
/* Get a basic date like: 'Wed Jun 30 21:49:08 1993' */
if(time(&t) == (time_t)-1 ||
!localtime_r(&t, &t2) ||
!asctime_r(&t2, date))
{
sp_message(ctx, LOG_WARNING, "unable to get date for header");
date[0] = 0;
return;
}
trim_end(date);
date_len = strlen(date);
{
#ifdef HAVE_TM_GMTOFF
time_t timezone = t2.tm_gmtoff;
const char *tzname[2] = { t2.tm_zone, t2.tm_zone };
snprintf(date + date_len, MAX_DATE_LENGTH - date_len, " %+03d%02d (%s)",
(int)(timezone / 3600), (int)(timezone % 3600),
tzname[t2.tm_isdst ? 1 : 0]);
#else
/* Apparently Solaris needs this nasty hack.... */
#define DAY_MIN (24 * HOUR_MIN)
#define HOUR_MIN 60
#define MIN_SEC 60
struct tm gmt;
struct tm *lt;
int off;
gmt = *gmtime(&t);
lt = localtime(&t);
off = (lt->tm_hour - gmt.tm_hour) * HOUR_MIN + lt->tm_min - gmt.tm_min;
if (lt->tm_year < gmt.tm_year)
off -= DAY_MIN;
else if (lt->tm_year > gmt.tm_year)
off += DAY_MIN;
else if (lt->tm_yday < gmt.tm_yday)
off -= DAY_MIN;
else if (lt->tm_yday > gmt.tm_yday)
off += DAY_MIN;
if (lt->tm_sec <= gmt.tm_sec - MIN_SEC)
off -= 1;
else if (lt->tm_sec >= gmt.tm_sec + MIN_SEC)
off += 1;
snprintf(date + date_len, MAX_DATE_LENGTH - date_len,
" %+03d%02d (%s)", (int)(off / HOUR_MIN), (int)(abs(off) % HOUR_MIN),
tzname[lt->tm_isdst ? 1 : 0]);
#endif
}
/* Break it off just in case */
date[MAX_DATE_LENGTH - 1] = 0;
}
/* Important: |header| should be a buffer of MAX_HEADER_LENGTH */
static int make_header(spctx_t* ctx, const char* format_str, char* header)
{
char date[MAX_DATE_LENGTH];
int remaining, l;
const char* f;
char* p;
date[0] = 0;
remaining = MAX_HEADER_LENGTH - 1;
p = header;
/* Parse the format string and replace special characters with our data */
for(f = format_str; *f && remaining > 0; f++)
{
/* A backslash escapes certain characters */
if(f[0] == '\\' && f[1] != 0)
{
switch(*(++f))
{
case 'r':
*p = '\r';
break;
case 'n':
*p = '\n';
break;
case 't':
*p = '\t';
break;
default:
*p = *f;
break;
}
++p;
--remaining;
}
/*
* Special symbols:
* %i: client's IP
* %l: server's IP
* %d: date
*/
else if(f[0] == '%' && f[1] != 0)
{
switch(*(++f))
{
case 'i':
l = strlen(ctx->client.peername);
strncpy(p, ctx->client.peername, remaining);
remaining -= l;
p += l;
break;
case 'l':
l = strlen(ctx->client.localname);
strncpy(p, ctx->client.localname, remaining);
remaining -= l;
p += l;
break;
case 'd':
if(date[0] == 0)
make_date(ctx, date);
l = strlen(date);
strncpy(p, date, remaining);
remaining -= l;
p += l;
break;
case '%':
*p = '%';
++p;
break;
default:
sp_messagex(ctx, LOG_WARNING, "invalid header symbol: %%%c", *f);
break;
};
}
else
{
*(p++) = *f;
remaining--;
}
}
if((p + 1) < (header + MAX_HEADER_LENGTH))
p[1] = 0;
header[MAX_HEADER_LENGTH - 1] = 0;
l = p - header;
return l >= MAX_HEADER_LENGTH ? MAX_HEADER_LENGTH - 1 : l;
}
int sp_done_data(spctx_t* ctx, const char *headertmpl)
{
FILE* file = 0;
int ret = 0;
char *line;
char header[MAX_HEADER_LENGTH] = "";
size_t header_len, line_len;
int header_prepend = 0;
ssize_t rc;
ASSERT(ctx->cachename[0]); /* Must still be around */
ASSERT(!ctx->cachefile); /* File must be closed */
memset(header, 0, sizeof(header));
/* Alloc line buffer */
line_len = SP_LINE_LENGTH;
if((line = (char *)malloc(line_len)) == NULL)
RETURN(-1);
/* Open the file */
file = fopen(ctx->cachename, "r");
if(file == NULL)
{
sp_message(ctx, LOG_ERR, "couldn't open cache file: %s", ctx->cachename);
RETURN(-1);
}
/* Ask the server for permission to send data */
if(spio_write_data(ctx, &(ctx->server), SMTP_DATA) == -1)
RETURN(-1);
if(read_server_response(ctx) == -1)
RETURN(-1);
/* If server returns an error then tell the client */
if(!is_first_word(ctx->server.line, DATA_RSP, KL(DATA_RSP)))
{
if(spio_write_data(ctx, &(ctx->client), ctx->server.line) == -1)
RETURN(-1);
sp_messagex(ctx, LOG_DEBUG, "server refused data transfer");
RETURN(0);
}
sp_messagex(ctx, LOG_DEBUG, "sending from cache file: %s", ctx->cachename);
if(headertmpl)
{
header_len = make_header(ctx, headertmpl, header);
if(is_first_word(RCVD_HEADER, header, KL(RCVD_HEADER)))
header_prepend = 1;
}
/* If we have to prepend the header, do it */
if(header[0] != '\0' && header_prepend)
{
if(spio_write_data_raw(ctx, &(ctx->server), (unsigned char*)header, header_len) == -1 ||
spio_write_data_raw(ctx, &(ctx->server), (unsigned char*)CRLF, KL(CRLF)) == -1)
RETURN(-1);
header[0] = '\0';
}
/* Transfer actual file data */
while((rc = getline(&line, &line_len, file)) != -1)
{
/*
* If the line is <CRLF>.<CRLF> we need to change it so that
* it doesn't end the email. We do this by adding a space.
* This won't occur much in clamsmtpd, but proxsmtpd might
* have filters that accidentally put this in.
*/
if(strcmp(line, "." CRLF) == 0)
strncpy(line, ". " CRLF, SP_LINE_LENGTH);
if(header[0] != '\0')
{
/*
* The first blank line we see means the headers are done.
* At this point we add in our virus checked header.
*/
if(is_blank_line(line))
{
if(spio_write_data_raw(ctx, &(ctx->server), (unsigned char*)header, header_len) == -1 ||
spio_write_data_raw(ctx, &(ctx->server), (unsigned char*)CRLF, KL(CRLF)) == -1)
RETURN(-1);
header[0] = '\0';
}
}
if(spio_write_data_raw(ctx, &(ctx->server), (unsigned char*)line, rc) == -1)
RETURN(-1);
}
if(ferror(file))
sp_message(ctx, LOG_ERR, "error reading cache file: %s", ctx->cachename);
if(ferror(file) || spio_write_data(ctx, &(ctx->server), DATA_END_SIG) == -1)
{
/* Tell the client it went wrong */
spio_write_data(ctx, &(ctx->client), SMTP_FAILED);
RETURN(-1);
}
sp_messagex(ctx, LOG_DEBUG, "sent email data");
/* Okay read the response from the server and echo it to the client */
if(read_server_response(ctx) == -1)
RETURN(-1);
if(spio_write_data(ctx, &(ctx->client), ctx->server.line) == -1)
RETURN(-1);
cleanup:
if(line)
free(line);
if(file)
fclose(file); /* read-only so no error check */
return ret;
}
int sp_fail_data(spctx_t* ctx, const char* smtp_status)
{
char buf[256 + KL(SMTP_REJPREFIX) + KL(CRLF) + 1];
char* t = NULL;
int len, x;
int pref = 0;
int crlf = 0;
if(smtp_status == NULL)
smtp_status = SMTP_FAILED;
x = strtol(smtp_status, &t, 10);
len = strlen(smtp_status);
/* We need 3 digits and CRLF at the end for a premade SMTP message */
if(x == 0 || t != smtp_status + 3)
pref = 1;
/* We need a CRLF at the end */
if(strcmp(smtp_status + (len - KL(CRLF)), CRLF) != 0)
crlf = 1;
if(pref || crlf)
{
/* Note that we truncate long lines */
snprintf(buf, sizeof(buf), "%s%.256s%s", pref ? SMTP_REJPREFIX : "",
smtp_status, crlf ? CRLF : "");
buf[sizeof(buf) - 1] = 0;
smtp_status = buf;
}
if(spio_write_data(ctx, &(ctx->client), smtp_status) == -1)
return -1;
/* Tell the server to forget about the current message */
if(spio_write_data(ctx, &(ctx->server), SMTP_RSET) == -1 ||
read_server_response(ctx) == -1)
return -1;
return 0;
}
static int read_server_response(spctx_t* ctx)
{
int r;
/* Read response line from the server */
if((r = spio_read_line(ctx, &(ctx->server), SPIO_DISCARD)) == -1)
return -1;
if(r == 0)
{
sp_messagex(ctx, LOG_ERR, "server disconnected unexpectedly");
/* Tell the client it went wrong */
spio_write_data(ctx, &(ctx->client), SMTP_FAILED);
return 0;
}
if(LINE_TOO_LONG(r))
sp_messagex(ctx, LOG_WARNING, "SMTP response line too long. discarded extra");
return 0;
}
static void do_server_noop(spctx_t* ctx)
{
if(spio_valid(&(ctx->server)))
{
if(spio_write_data(ctx, &(ctx->server), SMTP_NOOP) != -1)
spio_read_line(ctx, &(ctx->server), SPIO_DISCARD);
}
}
void sp_setup_forked(spctx_t* ctx, int file)
{
/* Signals we've messed with */
signal(SIGPIPE, SIG_DFL);
signal(SIGHUP, SIG_DFL);
signal(SIGINT, SIG_DFL);
signal(SIGTERM, SIG_DFL);
siginterrupt(SIGINT, 0);
siginterrupt(SIGTERM, 0);
if(ctx->sender)
setenv("SENDER", ctx->sender, 1);
if(ctx->recipients)
setenv("RECIPIENTS", ctx->recipients, 1);
if(file && ctx->cachename[0])
setenv("EMAIL", ctx->cachename, 1);
if(spio_valid(&(ctx->client)))
setenv("CLIENT", ctx->client.peername, 1);
if(ctx->xforwardaddr)
setenv("REMOTE", ctx->xforwardaddr, 1);
if(ctx->xforwardhelo)
setenv("REMOTE_HELO", ctx->xforwardhelo, 1);
if(spio_valid(&(ctx->server)))
setenv("SERVER", ctx->server.peername, 1);
setenv("TMPDIR", g_state.directory, 1);
}
/* ----------------------------------------------------------------------------------
* LOGGING
*/
const char kMsgDelimiter[] = ": ";
#define MAX_MSGLEN 1024
static void vmessage(spctx_t* ctx, int level, int err,
const char* msg, va_list ap)
{
char buf[MAX_MSGLEN];
int e = errno;
if(g_state.daemonized)
{
if(level >= LOG_DEBUG)
return;
}
else
{
if(g_state.debug_level < level)
return;
}
ASSERT(msg);
if(ctx)
snprintf(buf, MAX_MSGLEN, "%06X: %s%s", ctx->id, msg, err ? ": " : "");
else
snprintf(buf, MAX_MSGLEN, "%s%s", msg, err ? ": " : "");
if(err)
{
/* strerror_r doesn't want to work for us for some reason
len = strlen(buf);
strerror_r(e, buf + len, MAX_MSGLEN - len); */
sp_lock();
strncat(buf, strerror(e), MAX_MSGLEN);
sp_unlock();
}
/* As a precaution */
buf[MAX_MSGLEN - 1] = 0;
/* Either to syslog or stderr */
if(g_state.daemonized)
vsyslog(level, buf, ap);
else
vwarnx(buf, ap);
}
void sp_messagex(spctx_t* ctx, int level, const char* msg, ...)
{
va_list ap;
va_start(ap, msg);
vmessage(ctx, level, 0, msg, ap);
va_end(ap);
}
void sp_message(spctx_t* ctx, int level, const char* msg, ...)
{
va_list ap;
va_start(ap, msg);
vmessage(ctx, level, 1, msg, ap);
va_end(ap);
}
/* -----------------------------------------------------------------------
* LOCKING
*/
void sp_lock()
{
int r;
#ifdef _DEBUG
int wait = 0;
#endif
#ifdef _DEBUG
r = pthread_mutex_trylock(&g_mutex);
if(r == EBUSY)
{
wait = 1;
sp_message(NULL, LOG_DEBUG, "thread will block: %d", pthread_self());
r = pthread_mutex_lock(&g_mutex);
}
#else
r = pthread_mutex_lock(&g_mutex);
#endif
if(r != 0)
{
errno = r;
sp_message(NULL, LOG_CRIT, "threading problem. couldn't lock mutex");
}
#ifdef _DEBUG
else if(wait)
{
sp_message(NULL, LOG_DEBUG, "thread unblocked: %d", pthread_self());
}
#endif
}
void sp_unlock()
{
int r = pthread_mutex_unlock(&g_mutex);
if(r != 0)
{
errno = r;
sp_message(NULL, LOG_CRIT, "threading problem. couldn't unlock mutex");
}
}
/* -----------------------------------------------------------------------------
* CONFIG FILE
*/
int sp_parse_option(const char* name, const char* value)
{
char* t;
int ret = 0;
if(strcasecmp(CFG_MAXTHREADS, name) == 0)
{
g_state.max_threads = strtol(value, &t, 10);
if(*t || g_state.max_threads <= 1 || g_state.max_threads >= 1024)
errx(2, "invalid setting: " CFG_MAXTHREADS " (must be between 1 and 1024)");
ret = 1;
}
else if(strcasecmp(CFG_TIMEOUT, name) == 0)
{
g_state.timeout.tv_sec = strtol(value, &t, 10);
if(*t || g_state.timeout.tv_sec <= 0)
errx(2, "invalid setting: " CFG_TIMEOUT);
ret = 1;
}
else if(strcasecmp(CFG_KEEPALIVES, name) == 0)
{
g_state.keepalives = strtol(value, &t, 10);
if(*t || g_state.keepalives < 0)
errx(2, "invalid setting: " CFG_KEEPALIVES);
ret = 1;
}
else if(strcasecmp(CFG_XCLIENT, name) == 0)
{
if((g_state.xclient = strtob(value)) == -1)
errx(2, "invalid value for " CFG_XCLIENT);
ret = 1;
}
else if(strcasecmp(CFG_OUTADDR, name) == 0)
{
if(sock_any_pton(value, &(g_state.outaddr), SANY_OPT_DEFPORT(25)) == -1)
errx(2, "invalid " CFG_OUTADDR " socket name or ip: %s", value);
g_state.outname = value;
ret = 1;
}
else if(strcasecmp(CFG_LISTENADDR, name) == 0)
{
if(sock_any_pton(value, &(g_state.listenaddr), SANY_OPT_DEFANY | SANY_OPT_DEFPORT(DEFAULT_PORT)) == -1)
errx(2, "invalid " CFG_LISTENADDR " socket name or ip: %s", value);
g_state.listenname = value;
ret = 1;
}
else if(strcasecmp(CFG_TRANSPARENT, name) == 0)
{
if((g_state.transparent = strtob(value)) == -1)
errx(2, "invalid value for " CFG_TRANSPARENT);
ret = 1;
}
else if(strcasecmp(CFG_DIRECTORY, name) == 0)
{
if(strlen(value) == 0)
errx(2, "invalid setting: " CFG_DIRECTORY);
g_state.directory = value;
ret = 1;
}
else if(strcasecmp(CFG_USER, name) == 0)
{
if(strlen(value) == 0)
errx(2, "invalid setting: " CFG_USER);
g_state.user = value;
ret = 1;
}
else if(strcasecmp(CFG_PIDFILE, name) == 0)
{
if(g_state.pidfile != NULL)
sp_messagex(NULL, LOG_WARNING, "ignoring pid file specified on the command line. ");
if(strlen(value) == 0)
g_state.pidfile = NULL;
else
g_state.pidfile = value;
ret = 1;
}
/* Always pass through to program */
if(cb_parse_option(name, value) == 1)
ret = 1;
return ret;
}
static int parse_config_file(const char* configfile)
{
FILE* f = NULL;
long len;
char* p;
char* t;
char* n;
ASSERT(configfile);
ASSERT(!g_state._p);
f = fopen(configfile, "r");
if(f == NULL)
{
/* Soft errors when default config file and not found */
if((errno == ENOENT || errno == ENOTDIR))
return -1;
else
err(1, "couldn't open config file: %s", configfile);
}
/* Figure out size */
if(fseek(f, 0, SEEK_END) == -1 || (len = ftell(f)) == -1 || fseek(f, 0, SEEK_SET) == -1)
err(1, "couldn't seek config file: %s", configfile);
if((g_state._p = (char*)malloc(len + 2)) == NULL)
errx(1, "out of memory");
/* And read in one block */
if(fread(g_state._p, 1, len, f) != len)
err(1, "couldn't read config file: %s", configfile);
fclose(f);
sp_messagex(NULL, LOG_DEBUG, "read config file: %s", configfile);
/* Double null terminate the data */
p = g_state._p;
p[len] = '\n';
p[len + 1] = 0;
n = g_state._p;
/* Go through lines and process them */
while((t = strchr(n, '\n')) != NULL)
{
*t = 0;
p = n; /* Do this before cleaning below */
n = t + 1;
p = trim_start(p);
/* Comments and empty lines */
if(*p == 0 || *p == '#')
continue;
/* Look for the break between name: value */
t = strchr(p, ':');
if(t == NULL)
errx(2, "invalid config line: %s", p);
/* Null terminate and split value part */
*t = 0;
t++;
t = trim_space(t);
p = trim_space(p);
/* Pass it through our options parsers */
if(sp_parse_option(p, t) == 0)
/* If not recognized then it's invalid */
errx(2, "invalid config line: %s", p);
sp_messagex(NULL, LOG_DEBUG, "parsed option: %s: %s", p, t);
}
return 0;
}
|