New code to spawn off GPG/PGP to do stuff. Currently only deals with

	* mail-crypto.c: New code to spawn off GPG/PGP to do stuff.
	Currently only deals with decryption. From Nathan Thompson-Amato
	<ndt@jps.net>, with bunches of changes from me.

	* session.c (mail_request_dialog): Expose the password dialog to
	the rest of the app (for use by the GPG/PGP code).

	* mail-format.c (handle_text_plain): Handle special inline data
	types. (Currently uuencoding, BinHex, and PGP encryption.) This is
	not the best way to deal with it, but it works for now.
	(try_inline_pgp): Convert an inline PGP-encrypted message into a
	multipart/encrypted part.
	(try_inline_binhex): Convert an inline BinHex attachment into an
	application/mac-binhex40 part (which we currently don't deal
	with...)
	(try_uudecoding): Convert a uuencoded attachment to an
	application/octet-stream part.
	(handle_multipart_encrypted): Deal with RFC2015 MIME-encoded PGP
	encrypted messages. (From ndt.)

	* mail-display.c (mail_text_write, mail_error_write): New utility
	functions.

	* Makefile.am (evolution_mail_SOURCES): add mail-crypto.c

svn path=/trunk/; revision=4466

1 files changed, 405 insertions, 0 deletions

diff --git a/mail/mail-crypto.c b/mail/mail-crypto.c
new file mode 100644
index 0000000000..4db4357b44
--- /dev/null
+++ b/mail/mail-crypto.c
@@ -0,0 +1,405 @@
+/* -*- 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 */