path: root/mail/em-junk-filter.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*
 * Author:
 *  Radek Doulik <rodo@ximian.com>
 *
 * Copyright 2003 Ximian, Inc. (www.ximian.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA
 */

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <fcntl.h>
#include <errno.h>
#include <signal.h>
#include <string.h>
#include <pthread.h>

#include <camel/camel-data-wrapper.h>
#include <camel/camel-stream-fs.h>

#include "em-junk-filter.h"

#define LOCK(x) pthread_mutex_lock(&x)
#define UNLOCK(x) pthread_mutex_unlock(&x)

static pthread_mutex_t em_junk_sa_test_lock = PTHREAD_MUTEX_INITIALIZER;

static const char * em_junk_sa_get_name (void);
static gboolean em_junk_sa_check_junk (CamelMimeMessage *msg);
static void em_junk_sa_report_junk (CamelMimeMessage *msg);
static void em_junk_sa_report_notjunk (CamelMimeMessage *msg);
static void em_junk_sa_commit_reports (void);

static EMJunkPlugin spam_assassin_plugin =
{
    {
        em_junk_sa_get_name,
        1,
        em_junk_sa_check_junk,
        em_junk_sa_report_junk,
        em_junk_sa_report_notjunk,
        em_junk_sa_commit_reports,
    },
    NULL,
    NULL
};

static gboolean em_junk_sa_tested = FALSE;
static gboolean em_junk_sa_use_spamc = FALSE;
static gboolean em_junk_sa_available = FALSE;
static gint em_junk_sa_spamd_port = -1;

#define d(x) x

static const char *
em_junk_sa_get_name (void)
{
    return _("Spamassassin (built-in)");
}

static int
pipe_to_sa (CamelMimeMessage *msg, gchar *in, int argc, gchar **argv)
{
    CamelStream *stream;
    int result, status;
    int in_fds[2];
    pid_t pid;

    d(printf ("pipe_to_sa %s %s %s %s\n", argc > 0 ? argv [0] : "", argc > 1 ? argv [1] : "", argc > 2 ? argv [2] : "", argc > 3 ? argv [3] : ""));

    if (argc < 1 || argv[0] == '\0')
        return 0;
    
    if (pipe (in_fds) == -1) {
        /* camel_exception_setv (fms->ex, CAMEL_EXCEPTION_SYSTEM,
                      _("Failed to create pipe to '%s': %s"),
                      argv[0]->value.string, g_strerror (errno)); */
        return -1;
    }
    
    if (!(pid = fork ())) {
        /* child process */
        int maxfd, fd;
        
        fd = open ("/dev/null", O_WRONLY);
        
        if (dup2 (in_fds[0], STDIN_FILENO) < 0 ||
            dup2 (fd, STDOUT_FILENO) < 0 ||
            dup2 (fd, STDERR_FILENO) < 0)
            _exit (255);
        
        setsid ();
        
        maxfd = sysconf (_SC_OPEN_MAX);
        if (maxfd > 0) {
            for (fd = 0; fd < maxfd; fd++) {
                if (fd != STDIN_FILENO && fd != STDOUT_FILENO && fd != STDERR_FILENO)
                    close (fd);
            }
        }

        execvp (argv [0], argv);

        d(printf ("Could not execute %s: %s\n", argv [0], g_strerror (errno)));
        _exit (255);
    } else if (pid < 0) {
        /* camel_exception_setv (fms->ex, CAMEL_EXCEPTION_SYSTEM,
                      _("Failed to create create child process '%s': %s"),
                      argv[0]->value.string, g_strerror (errno)); */
        return -1;
    }
    
    /* parent process */
    close (in_fds[0]);
    fcntl (in_fds[1], F_SETFL, O_NONBLOCK);
    
    if (msg) {
        stream = camel_stream_fs_new_with_fd (in_fds[1]);
    
        camel_data_wrapper_write_to_stream (CAMEL_DATA_WRAPPER (msg), stream);
        camel_stream_flush (stream);
        camel_object_unref (CAMEL_OBJECT (stream));
    } else if (in) {
        write (in_fds [1], in, strlen (in));
        close (in_fds [1]);
    }

    result = waitpid (pid, &status, 0);
    
    if (result == -1 && errno == EINTR) {
        /* child process is hanging... */
        kill (pid, SIGTERM);
        sleep (1);
        result = waitpid (pid, &status, WNOHANG);
        if (result == 0) {
            /* ...still hanging, set phasers to KILL */
            kill (pid, SIGKILL);
            sleep (1);
            result = waitpid (pid, &status, WNOHANG);
        }
    }
    
    if (result != -1 && WIFEXITED (status))
        return WEXITSTATUS (status);
    else
        return -1;
}


#define NPORTS 1

static int
em_junk_sa_test_spamd_running (gint port)
{
    static gchar *sac_args [3] = {
        "/bin/sh",
        "-c",
        NULL
    };
    int retval;

    d(fprintf (stderr, "test if spamd is running (port %d)\n", port);)
    sac_args [2] = port > 0  ? g_strdup_printf ("spamc -x -p %d", port) : g_strdup_printf ("spamc -x");

    retval = pipe_to_sa (NULL, "From test@127.0.0.1", 3, sac_args) == 0;
    g_free (sac_args [2]);

    return retval;
}

static void
em_junk_sa_test_spamd ()
{
    gint i, port = 7830;
    static gchar *args [3] = {
        "/bin/sh",
        "-c",
        "spamassassin --version"
    };

    if (pipe_to_sa (NULL, NULL, 3, args))
        em_junk_sa_available = FALSE;
    else {
        em_junk_sa_available = TRUE;
        em_junk_sa_use_spamc = FALSE;

        /* if (em_junk_sa_test_spamd_running (-1)) {
        em_junk_sa_use_spamc = TRUE;
        em_junk_sa_spamd_port = -1;
        } else { */
        for (i = 0; i < NPORTS; i ++) {
            if (em_junk_sa_test_spamd_running (port)) {
                em_junk_sa_use_spamc = TRUE;
                em_junk_sa_spamd_port = port;
                break;
            }
            port ++;
        }
        /* } */

        if (!em_junk_sa_use_spamc) {
            static gchar *sad_args [3] = {
                "/bin/sh",
                "-c",
                NULL
            };
            gint i, port = 7830;

            d(fprintf (stderr, "looks like spamd is not running\n");)

                for (i = 0; i < NPORTS; i ++) {
                    d(fprintf (stderr, "trying to run spamd at port %d\n", port));

                    sad_args [2] = g_strdup_printf ("spamd --port %d --local --daemonize", port);
                    if (!pipe_to_sa (NULL, NULL, 3, sad_args)) {
                        g_free (sad_args [2]);
                        em_junk_sa_use_spamc = TRUE;
                        em_junk_sa_spamd_port = port;
                        d(fprintf (stderr, "success at port %d\n", port));
                        break;
                    }
                    g_free (sad_args [2]);
                    port ++;
                }
        }

        d(fprintf (stderr, "use spamd %d at port %d\n", em_junk_sa_use_spamc, em_junk_sa_spamd_port));
    }

    em_junk_sa_tested = TRUE;
}

static gboolean
em_junk_sa_is_available ()
{
    LOCK (em_junk_sa_test_lock);
    if (!em_junk_sa_tested)
        em_junk_sa_test_spamd ();
    UNLOCK (em_junk_sa_test_lock);

    return em_junk_sa_available;
}

static gboolean
em_junk_sa_check_junk (CamelMimeMessage *msg)
{
    static gchar *args [3] = {
        "/bin/sh",
        "-c",
        NULL
    };
    gint retval;

    d(fprintf (stderr, "em_junk_sa_check_junk\n"));

    if (!em_junk_sa_is_available ())
        return FALSE;

    args [2] = em_junk_sa_use_spamc
        ? (em_junk_sa_spamd_port == -1
           ? g_strdup ("spamc -c")         /* Exit with a non-zero exit code if the
                              tested message was junk */
           : g_strdup_printf ("spamc"
                      " -c"        /* Exit with a non-zero exit code if the
                              tested message was junk */
                      " -p %d", em_junk_sa_spamd_port))
        : g_strdup ("spamassassin"
                " --exit-code"         /* Exit with a non-zero exit code if the
                              tested message was junk */
                " --local");           /* Local tests only (no online tests) */

    retval = pipe_to_sa (msg, NULL, 3, args);

    g_free (args [2]);

    return retval;
}

static void
em_junk_sa_report_junk (CamelMimeMessage *msg)
{
    static gchar *args [3] = {
        "/bin/sh",
        "-c",
        "sa-learn"
        " --no-rebuild"        /* do not rebuild db */
        " --spam"              /* report junk */
        " --single"            /* single message */
        " --local"             /* local only */
    };

    d(fprintf (stderr, "em_junk_sa_report_junk\n"));

    if (em_junk_sa_is_available ())
        pipe_to_sa (msg, NULL, 3, args);
}

static void
em_junk_sa_report_notjunk (CamelMimeMessage *msg)
{
    static gchar *args [3] = {
        "/bin/sh",
        "-c",
        "sa-learn"
        " --no-rebuild"        /* do not rebuild db */
        " --ham"               /* report notjunk */
        " --single"            /* single message */
        " --local"             /* local only */
    };

    d(fprintf (stderr, "em_junk_sa_report_notjunk\n"));

    if (em_junk_sa_is_available ())
        pipe_to_sa (msg, NULL, 3, args);
}

static void
em_junk_sa_commit_reports (void)
{
    static gchar *args [3] = {
        "/bin/sh",
        "-c",
        "sa-learn"
        " --rebuild"           /* do not rebuild db */
        " --local"             /* local only */
    };

    d(fprintf (stderr, "em_junk_sa_commit_reports\n");)

    if (em_junk_sa_is_available ())
        pipe_to_sa (NULL, NULL, 3, args);
}

const EMJunkPlugin *
em_junk_filter_get_plugin (void)
{
    return &spam_assassin_plugin;
}