path: root/mail/openpgp-utils.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*
 *  Authors: Nathan Thompson-Amato <ndt@jps.net>
 *           Dan Winship <danw@helixcode.com>
 *           Jeffrey Stedfast <fejj@helixcode.com>
 *
 *  Copyright (C) Helix Code, Inc. (www.helixcode.com)
 *  
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *  
 *  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.
*/


#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <errno.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <dirent.h>

#include <signal.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <termios.h>
#include <unistd.h>
#include <signal.h>

#include <iconv.h>

#include <glib.h>
#include <libgnome/gnome-defs.h>
#include <libgnome/gnome-i18n.h> /* for _() macro */
#include "openpgp-utils.h"
#include "mail-session.h"

#define d(x)

struct _PgpValidity {
    gboolean valid;
    gchar *description;
};

static const gchar *pgp_path = NULL;
static PgpType pgp_type = PGP_TYPE_NONE;


static const gchar *
pgp_get_type_as_string (PgpType type)
{
    switch (type) {
    case PGP_TYPE_GPG:
        return "GnuPG";
    case PGP_TYPE_PGP5:
        return "PGP5";
    case PGP_TYPE_PGP2:
        return "PGP2.x";
    default:
        g_assert_not_reached ();
        return NULL;
    }
}

static gchar *
pgp_get_passphrase (const gchar *userid)
{
    gchar *passphrase, *prompt;
    const char *type;
    
    type = pgp_get_type_as_string (pgp_type);
    
    if (userid)
        prompt = g_strdup_printf (_("Please enter your %s passphrase for %s"),
                      type, userid);
    else
        prompt = g_strdup_printf (_("Please enter your %s passphrase"),
                      type);
    
    /* Use the userid as a key if possible, else be generic and use the type */
    passphrase = mail_session_request_dialog (prompt, TRUE, userid ? userid : type, FALSE);
    g_free (prompt);
    
    return passphrase;
}

static void
pgp_forget_passphrase (const char *key)
{
    if (!key)
        key = pgp_get_type_as_string (pgp_type);
    
    mail_session_forget_password (key);
}


/**
 * openpgp_init:
 * @path: path to pgp
 * @type: pgp program type
 *
 * Initializes pgp variables
 **/
void
openpgp_init (const gchar *path, PgpType type)
{
    pgp_path = path;
    pgp_type = type;
}


/**
 * openpgp_detect:
 * @text: input text
 *
 * Returns TRUE if it is found that the text contains a PGP encrypted
 * block otherwise returns FALSE.
 **/
gboolean
openpgp_detect (const gchar *text)
{
    if (strstr (text, "-----BEGIN PGP MESSAGE-----"))
        return TRUE;
    return FALSE;
}


/**
 * openpgp_sign_detect:
 * @text: input text
 *
 * Returns TRUE if it is found that the text contains a PGP signed
 * block otherwise returns FALSE.
 **/
gboolean
openpgp_sign_detect (const gchar *text)
{
    if (strstr (text, "-----BEGIN PGP SIGNED MESSAGE-----"))
        return TRUE;
    return FALSE;
}

static int
cleanup_child (pid_t child)
{
    int status;
    pid_t wait_result;
    sigset_t mask, omask;
    
    /* PGP5 closes fds before exiting, meaning this might be called
     * too early. So wait a bit for the result.
     */
    sigemptyset (&mask);
    sigaddset (&mask, SIGALRM);
    sigprocmask (SIG_BLOCK, &mask, &omask);
    alarm (1);
    wait_result = waitpid (child, &status, 0);
    alarm (0);
    sigprocmask (SIG_SETMASK, &omask, NULL);
    
    if (wait_result == -1 && errno == EINTR) {
        /* The child is hanging: send a friendly reminder. */
        kill (child, SIGTERM);
        sleep (1);
        wait_result = waitpid (child, &status, WNOHANG);
        if (wait_result == 0) {
            /* Still hanging; use brute force. */
            kill (child, SIGKILL);
            sleep (1);
            wait_result = waitpid (child, &status, WNOHANG);
        }
    }
    
    if (wait_result != -1 && WIFEXITED (status))
        return WEXITSTATUS (status);
    else
        return -1;
}

static void
cleanup_before_exec (int fd)
{
    int maxfd, i;
    
    maxfd = sysconf (_SC_OPEN_MAX);
    if (maxfd < 0)
        return;
    
    /* Loop over all fds. */
    for (i = 0; i < maxfd; i++) {
        if ((STDIN_FILENO != i) &&
            (STDOUT_FILENO != i) &&
            (STDERR_FILENO != i) &&
            (fd != i))
            close (i);
    }
}

static int
crypto_exec_with_passwd (const char *path, char *argv[], const char *input, int inlen,
             int passwd_fds[], const char *passphrase,
             char **output, int *outlen, char **diagnostics)
{
    fd_set fdset, write_fdset;
    int ip_fds[2], op_fds[2], diag_fds[2];
    int select_result, read_len, write_len;
    size_t tmp_len;
    pid_t child;
    char *buf, *diag_buf;
    const char *passwd_next, *input_next;
    size_t size, alloc_size, diag_size, diag_alloc_size;
    gboolean eof_seen, diag_eof_seen, passwd_eof_seen, input_eof_seen;
    size_t passwd_remaining, passwd_incr, input_remaining, input_incr;
    struct timeval timeout;
    
    
    if ((pipe (ip_fds) < 0 ) ||
        (pipe (op_fds) < 0 ) ||
        (pipe (diag_fds) < 0 )) {
        *diagnostics = g_strdup_printf ("Couldn't create pipe to %s: "
                        "%s", pgp_path,
                        g_strerror (errno));
        return 0;
    }
    
    if (!(child = fork ())) {
        /* In child */
        
        if ((dup2 (ip_fds[0], STDIN_FILENO) < 0 ) ||
            (dup2 (op_fds[1], STDOUT_FILENO) < 0 ) ||
            (dup2 (diag_fds[1], STDERR_FILENO) < 0 )) {
            _exit (255);
        }
        
        /* Dissociate from evolution-mail's controlling
         * terminal so that pgp/gpg won't be able to read from
         * it: PGP 2 will fall back to asking for the password
         * on /dev/tty if the passed-in password is incorrect.
         * This will make that fail rather than hanging.
         */
        setsid ();
        
        /* Close excess fds */
        cleanup_before_exec (passwd_fds[0]);
        
        execvp (path, argv);
        fprintf (stderr, "Could not execute %s: %s\n", argv[0],
             g_strerror (errno));
        _exit (255);
    } else if (child < 0) {
        *diagnostics = g_strdup_printf ("Cannot fork %s: %s",
                        argv[0], g_strerror (errno));
        return 0;
    }
    
    /* Parent */
    close (ip_fds[0]);
    close (op_fds[1]);
    close (diag_fds[1]);
    close (passwd_fds[0]);
    
    timeout.tv_sec = 10; /* timeout in seconds */
    timeout.tv_usec = 0;
    
    size = diag_size = 0;
    alloc_size = 4096;
    diag_alloc_size = 1024;
    eof_seen = diag_eof_seen = FALSE;
    
    buf = g_malloc (alloc_size);
    diag_buf = g_malloc (diag_alloc_size);
    
    passwd_next = passphrase;
    passwd_remaining = passphrase ? strlen (passphrase) : 0;
    passwd_incr = fpathconf (passwd_fds[1], _PC_PIPE_BUF);
    /* Use a reasonable default value on error. */
    if (passwd_incr <= 0)
        passwd_incr = 1024;
    passwd_eof_seen = FALSE;
    
    input_next = input;
    input_remaining = inlen;
    input_incr = fpathconf (ip_fds[1], _PC_PIPE_BUF);
    if (input_incr <= 0)
        input_incr = 1024;
    input_eof_seen = FALSE;
    
    while (!(eof_seen && diag_eof_seen)) {
        FD_ZERO (&fdset);
        if (!eof_seen)
            FD_SET (op_fds[0], &fdset);
        if (!diag_eof_seen)
            FD_SET (diag_fds[0], &fdset);
        
        FD_ZERO (&write_fdset);
        if (!passwd_eof_seen)
            FD_SET (passwd_fds[1], &write_fdset);
        if (!input_eof_seen)
            FD_SET (ip_fds[1], &write_fdset);
        
        select_result = select (FD_SETSIZE, &fdset, &write_fdset,
                    NULL, &timeout);
        if (select_result < 0) {
            if (errno == EINTR)
                continue;
            break;
        }
        if (select_result == 0) {
            /* timeout */
            break;
        }
        
        if (FD_ISSET (op_fds[0], &fdset)) {
            /* More output is available. */
            
            if (size + 4096 > alloc_size) {
                alloc_size += 4096;
                buf = g_realloc (buf , alloc_size);
            }
            read_len = read (op_fds[0], &buf[size],
                     alloc_size - size - 1);
            if (read_len < 0) {
                if (errno == EINTR)
                    continue;
                break;
            }
            if (read_len == 0)
                eof_seen = TRUE;
            size += read_len;
        }
        
        if (FD_ISSET(diag_fds[0], &fdset) ) {
            /* More stderr is available. */
            
            if (diag_size + 1024 > diag_alloc_size) {
                diag_alloc_size += 1024;
                diag_buf = g_realloc (diag_buf,
                              diag_alloc_size);
            }
            
            read_len = read (diag_fds[0], &diag_buf[diag_size],
                     diag_alloc_size - diag_size - 1);
            if (read_len < 0) {
                if (errno == EINTR)
                    continue;
                break;
            }
            if (read_len == 0)
                diag_eof_seen = TRUE;
            diag_size += read_len;
        }
        
        if (FD_ISSET(passwd_fds[1], &write_fdset)) {
            /* Ready for more password input. */
            
            tmp_len = passwd_incr;
            if (tmp_len > passwd_remaining)
                tmp_len = passwd_remaining;
            write_len = write (passwd_fds[1], passwd_next,
                       tmp_len);
            if (write_len < 0) {
                if (errno == EINTR)
                    continue;
                break;
            }
            passwd_next += write_len;
            passwd_remaining -= write_len;
            if (passwd_remaining == 0) {
                close (passwd_fds[1]);
                passwd_eof_seen = TRUE;
            }
        }
        
        if (FD_ISSET(ip_fds[1], &write_fdset)) {
            /* Ready for more ciphertext input. */
            
            tmp_len = input_incr;
            if (tmp_len > input_remaining)
                tmp_len = input_remaining;
            write_len = write (ip_fds[1], input_next, tmp_len);
            if (write_len < 0) {
                if (errno == EINTR)
                    continue;
                break;
            }
            input_next += write_len;
            input_remaining -= write_len;
            if (input_remaining == 0 ) {
                close (ip_fds[1]);
                input_eof_seen = TRUE;
            }
        }
    }
    
    buf[size] = 0;
    diag_buf[diag_size] = 0;
    close (op_fds[0]);
    close (diag_fds[0]);
    
    *output = buf;
    if (outlen)
        *outlen = size;
    *diagnostics = diag_buf;
    
    return cleanup_child (child);
}

/*----------------------------------------------------------------------*
 *                     Public crypto functions
 *----------------------------------------------------------------------*/

/**
 * openpgp_decrypt:
 * @ciphertext: ciphertext to decrypt
 * @cipherlen: ciphertext length
 * @outlen: output length of the decrypted data (to be set by #openpgp_decrypt)
 * @ex: exception
 *
 * Returns an allocated buffer containing the decrypted ciphertext. If
 * the cleartext is plain text then you may treat it like a normal
 * string as it will be NUL terminated, however #outlen is also set in
 * the case that the cleartext is a binary stream.
 **/
gchar *
openpgp_decrypt (const gchar *ciphertext, gint cipherlen, gint *outlen, CamelException *ex)
{
    char *argv[15];
    char *plaintext = NULL;
    char *diagnostics = NULL;
    char *passphrase;
    int passwd_fds[2];
    char passwd_fd[32];
    int retval, i;
    
    if (pgp_type == PGP_TYPE_NONE) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      _("No GPG/PGP program available."));
        return NULL;
    }
    
    passphrase = pgp_get_passphrase (NULL);
    if (!passphrase) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      _("No password provided."));
        return NULL;
    }
    
    if (pipe (passwd_fds) < 0) {
        g_free (passphrase);
        pgp_forget_passphrase (NULL);
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      _("Couldn't create pipe to GPG/PGP: %s"),
                      g_strerror (errno));
        return NULL;
    }
    
    i = 0;
    switch (pgp_type) {
    case PGP_TYPE_GPG:
        argv[i++] = "gpg";
        argv[i++] = "--verbose";
        argv[i++] = "--yes";
        argv[i++] = "--batch";
        
        argv[i++] = "--output";
        argv[i++] = "-";            /* output to stdout */
        
        argv[i++] = "--decrypt";
        
        argv[i++] = "--passphrase-fd";
        sprintf (passwd_fd, "%d", passwd_fds[0]);
        argv[i++] = passwd_fd;
        break;
    case PGP_TYPE_PGP5:
        argv[i++] = "pgpv";
        argv[i++] = "-f";
        argv[i++] = "+batchmode=1";
        
        sprintf (passwd_fd, "PGPPASSFD=%d", passwd_fds[0]);
        putenv (passwd_fd);
        break;
    case PGP_TYPE_PGP2:
        argv[i++] = "pgp";
        argv[i++] = "-f";
        
        sprintf (passwd_fd, "PGPPASSFD=%d", passwd_fds[0]);
        putenv (passwd_fd);
        break;
    default:
        g_assert_not_reached ();
        break;
    }
    
    argv[i++] = NULL;
    
    retval = crypto_exec_with_passwd (pgp_path, argv,
                      ciphertext, cipherlen,
                      passwd_fds, passphrase,
                      &plaintext, outlen,
                      &diagnostics);
    g_free (passphrase);
    
    if (retval != 0 || !*plaintext) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      "%s", diagnostics);
        g_free (plaintext);
        g_free (diagnostics);
        pgp_forget_passphrase (NULL);
        return NULL;
    }
    
    g_free (diagnostics);
    
    return plaintext;
}


/**
 * openpgp_encrypt:
 * @in: data to encrypt
 * @inlen: input length of input data
 * @recipients: An array of recipient ids
 * @sign: TRUE if you want to sign as well as encrypt
 * @userid: userid to use when signing (assuming #sign is TRUE)
 * @ex: exception
 *
 * Returns an allocated string containing the ciphertext.
 **/
gchar *
openpgp_encrypt (const gchar *in, gint inlen, const GPtrArray *recipients,
         gboolean sign, const gchar *userid, CamelException *ex)
{
    GPtrArray *recipient_list = NULL;
    GPtrArray *argv = NULL;
    int retval, r;
    char *ciphertext = NULL;
    char *diagnostics = NULL;
    int passwd_fds[2];
    char passwd_fd[32];
    char *passphrase = NULL;
    
    if (pgp_type == PGP_TYPE_NONE) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      _("No GPG/PGP program available."));
        return NULL;
    }
    
    if (sign) {
        /* we only need a passphrase if we intend on signing */
        passphrase = pgp_get_passphrase (NULL);
        if (!passphrase) {
            camel_exception_set (ex, CAMEL_EXCEPTION_SYSTEM,
                         _("No password provided."));
            return NULL;
        }
    }
    
    if (pipe (passwd_fds) < 0) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      _("Couldn't create pipe to GPG/PGP: %s"),
                      g_strerror (errno));
        
        if (sign) {
            g_free (passphrase);
            pgp_forget_passphrase (NULL);
        }
        
        return NULL;
    }
    
    /* check to make sure we have recipients */
    if (recipients->len == 0) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      _("No recipients specified"));
        
        if (sign) {
            g_free (passphrase);
            pgp_forget_passphrase (NULL);
        }
        
        return NULL;
    }
    
    argv = g_ptr_array_new ();
    recipient_list = g_ptr_array_new ();
    
    switch (pgp_type) {
    case PGP_TYPE_GPG:
        for (r = 0; r < recipients->len; r++) {
            char *buf, *recipient;
            
            recipient = recipients->pdata[r];
            buf = g_strdup_printf ("-r %s", recipient);
            g_ptr_array_add (recipient_list, buf);
            g_free (recipient);
        }
        
        g_ptr_array_add (argv, "gpg");
        
        g_ptr_array_add (argv, "--verbose");
        g_ptr_array_add (argv, "--yes");
        g_ptr_array_add (argv, "--batch");
        g_ptr_array_add (argv, "--no-tty");
        
        g_ptr_array_add (argv, "--armor");
        
        for (r = 0; r < recipient_list->len; r++)
            g_ptr_array_add (argv, recipient_list->pdata[r]);
        
        g_ptr_array_add (argv, "--output");
        g_ptr_array_add (argv, "-");            /* output to stdout */
        
        g_ptr_array_add (argv, "--encrypt");
        
        if (sign) {
            g_ptr_array_add (argv, "--sign");
            
            g_ptr_array_add (argv, "-u");
            g_ptr_array_add (argv, (gchar *) userid);
            
            g_ptr_array_add (argv, "--passphrase-fd");
            sprintf (passwd_fd, "%d", passwd_fds[0]);
            g_ptr_array_add (argv, passwd_fd);
        }
        break;
    case PGP_TYPE_PGP5:
        for (r = 0; r < recipients->len; r++) {
            char *buf, *recipient;
            
            recipient = recipients->pdata[r];
            buf = g_strdup_printf ("-r %s", recipient);
            g_ptr_array_add (recipient_list, buf);
            g_free (recipient);
        }
        
        g_ptr_array_add (argv, "pgpe");
        
        for (r = 0; r < recipient_list->len; r++)
            g_ptr_array_add (argv, recipient_list->pdata[r]);
        
        g_ptr_array_add (argv, "-f");
        g_ptr_array_add (argv, "-z");
        g_ptr_array_add (argv, "-a");
        g_ptr_array_add (argv, "-o");
        g_ptr_array_add (argv, "-");        /* output to stdout */
        
        if (sign) {
            g_ptr_array_add (argv, "-s");
            
            g_ptr_array_add (argv, "-u");
            g_ptr_array_add (argv, (gchar *) userid);
            
            sprintf (passwd_fd, "PGPPASSFD=%d", passwd_fds[0]);
            putenv (passwd_fd);
        }
        break;
    case PGP_TYPE_PGP2:
        for (r = 0; r < recipients->len; r++) {
            char *buf, *recipient;
            
            recipient = recipients->pdata[r];
            buf = g_strdup (recipient);
            g_ptr_array_add (recipient_list, buf);
            g_free (recipient);
        }
        
        g_ptr_array_add (argv, "pgp");
        g_ptr_array_add (argv, "-f");
        g_ptr_array_add (argv, "-e");
        g_ptr_array_add (argv, "-a");
        g_ptr_array_add (argv, "-o");
        g_ptr_array_add (argv, "-");
        
        for (r = 0; r < recipient_list->len; r++)
            g_ptr_array_add (argv, recipient_list->pdata[r]);
        
        if (sign) {
            g_ptr_array_add (argv, "-s");
            
            g_ptr_array_add (argv, "-u");
            g_ptr_array_add (argv, (gchar *) userid);
            
            sprintf (passwd_fd, "PGPPASSFD=%d", passwd_fds[0]);
            putenv (passwd_fd);
        }
        break;
    default:
        g_assert_not_reached ();
        break;
    }
    
    g_ptr_array_add (argv, NULL);
    
    retval = crypto_exec_with_passwd (pgp_path, (char **) argv->pdata,
                      in, inlen, passwd_fds,
                      passphrase, &ciphertext, NULL,
                      &diagnostics);
    
    g_free (passphrase);
    g_ptr_array_free (argv, TRUE);
    
    if (retval != 0 || !*ciphertext) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      "%s", diagnostics);
        g_free (ciphertext);
        ciphertext = NULL;
        if (sign)
            pgp_forget_passphrase (NULL);
    }
    
    if (recipient_list) {
        for (r = 0; r < recipient_list->len; r++)
            g_free (recipient_list->pdata[r]);
        g_ptr_array_free (recipient_list, TRUE);
    }
    
    g_free (diagnostics);
    
    return ciphertext;
}


/**
 * openpgp_clearsign:
 * @plaintext: plain readable text to clearsign
 * @userid: userid to sign with
 * @hash: Preferred hash function (md5 or sha1)
 * @ex: exception
 *
 * Returns an allocated string containing the clearsigned plaintext
 * using the preferred hash.
 **/
gchar *
openpgp_clearsign (const gchar *plaintext, const gchar *userid,
           PgpHashType hash, CamelException *ex)
{
    char *argv[15];
    char *ciphertext = NULL;
    char *diagnostics = NULL;
    char *passphrase = NULL;
    char *hash_str = NULL;
    int passwd_fds[2];
    char passwd_fd[32];
    int retval, i;
    
    if (pgp_type == PGP_TYPE_NONE) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      _("No GPG/PGP program available."));
        return NULL;
    }
    
    passphrase = pgp_get_passphrase (userid);
    if (!passphrase) {
        camel_exception_set (ex, CAMEL_EXCEPTION_SYSTEM,
                     _("No password provided."));
        return NULL;
    }
    
    if (pipe (passwd_fds) < 0) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      _("Couldn't create pipe to GPG/PGP: %s"),
                      g_strerror (errno));
        
        g_free (passphrase);
        pgp_forget_passphrase (userid);
        
        return NULL;
    }
    
    switch (hash) {
    case PGP_HASH_TYPE_MD5:
        hash_str = "MD5";
        break;
    case PGP_HASH_TYPE_SHA1:
        hash_str = "SHA1";
        break;
    default:
        break;
    }
    
    i = 0;
    switch (pgp_type) {
    case PGP_TYPE_GPG:
        argv[i++] = "gpg";
        
        argv[i++] = "--clearsign";
        
        if (hash_str) {
            argv[i++] = "--digest-algo";
            argv[i++] = hash_str;
        }
        
        if (userid) {
            argv[i++] = "-u";
            argv[i++] = (char *) userid;
        }
        
        argv[i++] = "--verbose";
        argv[i++] = "--yes";
        argv[i++] = "--batch";
        
        argv[i++] = "--armor";
        
        argv[i++] = "--output";
        argv[i++] = "-";            /* output to stdout */
        
        argv[i++] = "--passphrase-fd";
        sprintf (passwd_fd, "%d", passwd_fds[0]);
        argv[i++] = passwd_fd;
        break;
    case PGP_TYPE_PGP5:
        /* FIXME: modify to respect hash */
        argv[i++] = "pgps";
        
        if (userid) {
            argv[i++] = "-u";
            argv[i++] = (char *) userid;
        }
        
        argv[i++] = "-f";
        argv[i++] = "-z";
        argv[i++] = "-a";
        argv[i++] = "-o";
        argv[i++] = "-";        /* output to stdout */
        
        sprintf (passwd_fd, "PGPPASSFD=%d", passwd_fds[0]);
        putenv (passwd_fd);
        break;
    case PGP_TYPE_PGP2:
        /* FIXME: modify to respect hash */
        argv[i++] = "pgp";
        
        if (userid) {
            argv[i++] = "-u";
            argv[i++] = (char *) userid;
        }
        
        argv[i++] = "-f";
        argv[i++] = "-a";
        argv[i++] = "-o";
        argv[i++] = "-";
        
        argv[i++] = "-st";
        sprintf (passwd_fd, "PGPPASSFD=%d", passwd_fds[0]);
        putenv (passwd_fd);
        break;
    default:
        g_assert_not_reached ();
        break;
    }
    
    argv[i++] = NULL;
    
    retval = crypto_exec_with_passwd (pgp_path, argv,
                      plaintext, strlen (plaintext),
                      passwd_fds, passphrase,
                      &ciphertext, NULL,
                      &diagnostics);
    
    g_free (passphrase);
    
    if (retval != 0 || !*ciphertext) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      "%s", diagnostics);
        g_free (ciphertext);
        ciphertext = NULL;
        pgp_forget_passphrase (userid);
    }
    
    g_free (diagnostics);
    
    return ciphertext;
}


/**
 * openpgp_sign:
 * @in: input data to sign
 * @inlen: length of input data
 * @userid: userid to sign with
 * @hash: preferred hash type (md5 or sha1)
 * @ex: exception
 *
 * Returns an allocated string containing the detached signature using
 * the preferred hash.
 **/
gchar *
openpgp_sign (const gchar *in, gint inlen, const gchar *userid,
          PgpHashType hash, CamelException *ex)
{
    char *argv[20];
    char *ciphertext = NULL;
    char *diagnostics = NULL;
    char *passphrase = NULL;
    char *hash_str = NULL;
    int passwd_fds[2];
    char passwd_fd[32];
    int retval, i;
    
    if (pgp_type == PGP_TYPE_NONE) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      _("No GPG/PGP program available."));
        return NULL;
    }
    
    passphrase = pgp_get_passphrase (userid);
    if (!passphrase) {
        camel_exception_set (ex, CAMEL_EXCEPTION_SYSTEM,
                     _("No password provided."));
        return NULL;
    }
    
    if (pipe (passwd_fds) < 0) {
        g_free (passphrase);
        pgp_forget_passphrase (userid);
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      _("Couldn't create pipe to GPG/PGP: %s"),
                      g_strerror (errno));
        return NULL;
    }
    
    switch (hash) {
    case PGP_HASH_TYPE_MD5:
        hash_str = "MD5";
        break;
    case PGP_HASH_TYPE_SHA1:
        hash_str = "SHA1";
        break;
    default:
        break;
    }
    
    i = 0;
    switch (pgp_type) {
    case PGP_TYPE_GPG:
        argv[i++] = "gpg";
        
        argv[i++] = "--sign";
        argv[i++] = "-b";
        if (hash_str) {
            argv[i++] = "--digest-algo";
            argv[i++] = hash_str;
        }
        
        if (userid) {
            argv[i++] = "-u";
            argv[i++] = (char *) userid;
        }
        
        argv[i++] = "--verbose";
        argv[i++] = "--yes";
        argv[i++] = "--batch";
        
        argv[i++] = "--armor";
        
        argv[i++] = "--output";
        argv[i++] = "-";            /* output to stdout */
        
        argv[i++] = "--passphrase-fd";
        sprintf (passwd_fd, "%d", passwd_fds[0]);
        argv[i++] = passwd_fd;
        break;
    case PGP_TYPE_PGP5:
        /* FIXME: respect hash */
        argv[i++] = "pgps";
        
        if (userid) {
            argv[i++] = "-u";
            argv[i++] = (char *) userid;
        }
        
        argv[i++] = "-b";
        argv[i++] = "-f";
        argv[i++] = "-z";
        argv[i++] = "-a";
        argv[i++] = "-o";
        argv[i++] = "-";        /* output to stdout */
        
        sprintf (passwd_fd, "PGPPASSFD=%d", passwd_fds[0]);
        putenv (passwd_fd);
        break;
    case PGP_TYPE_PGP2:
        /* FIXME: respect hash */
        argv[i++] = "pgp";
        
        if (userid) {
            argv[i++] = "-u";
            argv[i++] = (char *) userid;
        }
        
        argv[i++] = "-f";
        argv[i++] = "-a";
        argv[i++] = "-o";
        argv[i++] = "-";
        
        argv[i++] = "-sb"; /* create a detached signature */
        sprintf (passwd_fd, "PGPPASSFD=%d", passwd_fds[0]);
        putenv (passwd_fd);
        break;
    default:
        g_assert_not_reached ();
        break;
    }
    
    argv[i++] = NULL;
    
    retval = crypto_exec_with_passwd (pgp_path, argv,
                      in, inlen,
                      passwd_fds, passphrase,
                      &ciphertext, NULL,
                      &diagnostics);
    
    g_free (passphrase);
    
    if (retval != 0 || !*ciphertext) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      "%s", diagnostics);
        g_free (ciphertext);
        ciphertext = NULL;
        pgp_forget_passphrase (userid);
    }
    
    g_free (diagnostics);
    
    return ciphertext;
}

static char *
swrite (const char *data, int len)
{
    char *template;
    int fd;
    
    template = g_strdup ("/tmp/evolution-pgp.XXXXXX");
    fd = mkstemp (template);
    if (fd == -1) {
        g_free (template);
        return NULL;
    }
    
    write (fd, data, len);
    close (fd);
    
    return template;
}

PgpValidity *
openpgp_verify (const gchar *in, gint inlen, const gchar *sigin, gint siglen, CamelException *ex)
{
    char *argv[20];
    char *cleartext = NULL;
    char *diagnostics = NULL;
    int passwd_fds[2];
    char *sigfile = NULL;
    int retval, i, clearlen;
    PgpValidity *valid = NULL;
    
    
    if (pgp_type == PGP_TYPE_NONE) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      _("No GPG/PGP program available."));
        return NULL;
    }
    
    if (pipe (passwd_fds) < 0) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      _("Couldn't create pipe to GPG/PGP: %s"),
                      g_strerror (errno));
        return NULL;
    }
    
    if (sigin != NULL && siglen) {
        /* We are going to verify a detached signature so save
           the signature to a temp file. */
        sigfile = swrite (sigin, siglen);
        if (!sigfile) {
            camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                          _("Couldn't create temp file: %s"),
                          g_strerror (errno));
            return NULL;
        }
    }
    
    i = 0;
    switch (pgp_type) {
    case PGP_TYPE_GPG:
        argv[i++] = "gpg";
        
        argv[i++] = "--verify";
        
        argv[i++] = "--no-tty";
        /*argv[i++] = "--verbose";*/
        /*argv[i++] = "--yes";*/
        /*argv[i++] = "--batch";*/
        
        if (sigin != NULL && siglen)
            argv[i++] = sigfile;
        
        argv[i++] = "-";
        break;
    case PGP_TYPE_PGP5:
        argv[i++] = "pgpv";
        
        argv[i++] = "-z";
        
        if (sigin != NULL && siglen)
            argv[i++] = sigfile;
        
        argv[i++] = "-f";
        
        break;
    case PGP_TYPE_PGP2:
        argv[i++] = "pgp";
        
        if (sigin != NULL && siglen)
            argv[i++] = sigfile;
        
        argv[i++] = "-f";
        
        break;
    default:
        g_assert_not_reached ();
        break;
    }
    
    argv[i++] = NULL;
    
    clearlen = 0;
    retval = crypto_exec_with_passwd (pgp_path, argv,
                      in, inlen,
                      passwd_fds, NULL,
                      &cleartext, &clearlen,
                      &diagnostics);
    
    /* cleanup */
    if (sigfile) {
        unlink (sigfile);
        g_free (sigfile);
    }
    
    valid = openpgp_validity_new ();
    
    if (retval != 0) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      "%s", diagnostics);
        
        openpgp_validity_set_valid (valid, FALSE);
    } else {
        openpgp_validity_set_valid (valid, TRUE);
    }
    
    if (diagnostics) {
        char *charset;
        const char *buf;
        char *desc, *outbuf;
        iconv_t cd;
        size_t len, outlen;
        
        charset = getenv ("CHARSET");
        if (!charset)
            charset = "ISO-8859-1";
        
        cd = iconv_open ("UTF-8", charset);
        
        len = strlen (diagnostics);
        outlen = 2 * len;
        
        outbuf = desc = g_malloc0 (outlen + 1);
        buf = diagnostics;
        if (cd == (iconv_t) -1 || iconv (cd, &buf, &len, &outbuf, &outlen) == -1) {
            g_free (desc);
            desc = g_strdup (diagnostics);
        }
        
        if (cd != (iconv_t) -1)
            iconv_close (cd);
        
        openpgp_validity_set_description (valid, desc);
        g_free (desc);
    }
    
    g_free (diagnostics);
    g_free (cleartext);
    
    return valid;
}


/* PGP Validity */

PgpValidity *
openpgp_validity_new (void)
{
    PgpValidity *validity;
    
    validity = g_new (PgpValidity, 1);
    validity->valid = FALSE;
    validity->description = NULL;
    
    return validity;
}

void
openpgp_validity_init (PgpValidity *validity)
{
    g_assert (validity != NULL);
    
    validity->valid = FALSE;
    validity->description = NULL;
}

gboolean
openpgp_validity_get_valid (PgpValidity *validity)
{
    if (validity == NULL)
        return FALSE;
    
    return validity->valid;
}

void
openpgp_validity_set_valid (PgpValidity *validity, gboolean valid)
{
    g_assert (validity != NULL);
    
    validity->valid = valid;
}

gchar *
openpgp_validity_get_description (PgpValidity *validity)
{
    if (validity == NULL)
        return NULL;
    
    return validity->description;
}

void
openpgp_validity_set_description (PgpValidity *validity, const gchar *description)
{
    g_assert (validity != NULL);
    
    g_free (validity->description);
    validity->description = g_strdup (description);
}

void
openpgp_validity_clear (PgpValidity *validity)
{
    g_assert (validity != NULL);
    
    validity->valid = FALSE;
    g_free (validity->description);
    validity->description = NULL;
}

void
openpgp_validity_free (PgpValidity *validity)
{
    if (validity == NULL)
        return;
    
    g_free (validity->description);
    g_free (validity);
}