/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*
* mail-crypto.h: OpenPGP en/decryption & signature code
*
* FIXME FIXME FIXME: This should be in its own library or component
*/
/*
* Authors:
* Nathan Thompson-Amato <ndt@jps.net>
* Dan Winship <danw@helixcode.com>
*
* Copyright 2000, Helix Code, Inc. (http://www.helixcode.com)
* Copyright 2000, Nathan Thompson-Amato
* Copyright 1999, 2000, Anthony Mulcahy
*
* 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 Street #330, Boston, MA 02111-1307, USA.
*
*/
#include "config.h"
#ifdef PGP_PROGRAM
#include <stdlib.h>
#include <string.h>
#include <glib.h>
#include <gnome.h>
#include "mail.h"
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <signal.h>
#include <stdio.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>
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 (char *path, char *argv[], const char *input,
int passwd_fds[], const char *passphrase,
char **output, 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;
long tmp;
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_PROGRAM,
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 = strlen (passphrase);
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 = strlen (input);
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;
*diagnostics = diag_buf;
return cleanup_child (child);
}
/*----------------------------------------------------------------------*
* Public crypto functions
*----------------------------------------------------------------------*/
char *
mail_crypto_openpgp_decrypt (const char *ciphertext, const char *passphrase,
CamelException *ex)
{
int retval;
char *path, *argv[12];
int i;
char *plaintext = NULL;
char *diagnostics = NULL;
int passwd_fds[2];
char passwd_fd[32];
#ifndef PGP_PROGRAM
camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
"No GPG/PGP program available.");
return NULL;
#endif
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;
}
i = 0;
#if defined(GPG_PATH)
path = GPG_PATH;
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;
#elif defined(PGP5_PATH)
path = PGP5_PATH;
argv[i++] = "pgpv";
argv[i++] = "-f";
argv[i++] = "+batchmode=1";
sprintf (passwd_fd, "PGPPASSFD=%d", passwd_fds[0]);
putenv (passwd_fd);
#else
path = PGP_PATH;
argv[i++] = "pgp";
argv[i++] = "-f";
sprintf (passwd_fd, "PGPPASSFD=%d", passwd_fds[0]);
putenv (passwd_fd);
#endif
argv[i++] = NULL;
retval = crypto_exec_with_passwd (path, argv, ciphertext, passwd_fds,
passphrase, &plaintext,
&diagnostics);
if (retval != 0 || !*plaintext) {
camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
"%s", diagnostics);
g_free (plaintext);
g_free (diagnostics);
return NULL;
}
g_free (diagnostics);
return plaintext;
}
#endif /* PGP_PROGRAM */
