--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/mcabber/src/pgp.c Sun Nov 26 10:30:52 2006 +0100
@@ -0,0 +1,460 @@
+/*
+ * pgp.c -- PGP utility functions
+ *
+ * Copyright (C) 2006 Mikael Berthe <bmikael@lists.lilotux.net>
+ * Some parts inspired by centericq (impgp.cc)
+ *
+ * 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
+ */
+
+#include <config.h>
+
+#ifdef HAVE_GPGME
+
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <locale.h>
+#include <sys/mman.h>
+#include <glib.h>
+
+#include "pgp.h"
+#include "logprint.h"
+
+#define MIN_GPGME_VERSION "1.0.0"
+
+static struct gpg_struct
+{
+ int enabled;
+ char *private_key;
+ char *passphrase;
+} gpg;
+
+
+// gpg_init(priv_key, passphrase)
+// Initialize the GPG sub-systems. This function must be invoked early.
+// Note: priv_key & passphrase are optional, they can be set later.
+// This function returns 0 if gpgme is available and initialized;
+// if not it returns the gpgme error code.
+int gpg_init(const char *priv_key, const char *passphrase)
+{
+ gpgme_error_t err;
+
+ // Check for version and OpenPGP protocol support.
+ if (!gpgme_check_version(MIN_GPGME_VERSION)) {
+ scr_LogPrint(LPRINT_LOGNORM|LPRINT_NOTUTF8,
+ "GPGME initialization error: %s", gpgme_strerror(err));
+ return -1;
+ }
+
+ err = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
+ if (err) {
+ scr_LogPrint(LPRINT_LOGNORM|LPRINT_NOTUTF8,
+ "GPGME initialization error: %s", gpgme_strerror(err));
+ return err;
+ }
+
+ // Set the locale information.
+ gpgme_set_locale(NULL, LC_CTYPE, setlocale(LC_CTYPE, NULL));
+ gpgme_set_locale(NULL, LC_MESSAGES, setlocale(LC_MESSAGES, NULL));
+
+ // Store private data.
+ gpg_set_private_key(priv_key);
+ gpg_set_passphrase(passphrase);
+
+ gpg.enabled = 1;
+ return 0;
+}
+
+// gpg_terminate()
+// Destroy data and free memory.
+void gpg_terminate(void)
+{
+ gpg.enabled = 0;
+ gpg_set_passphrase(NULL);
+ gpg_set_private_key(NULL);
+}
+
+// gpg_set_passphrase(passphrase)
+// Set the current passphrase (use NULL to erase it).
+void gpg_set_passphrase(const char *passphrase)
+{
+ // Remove current passphrase
+ if (gpg.passphrase) {
+ ssize_t len = strlen(gpg.passphrase);
+ memset(gpg.passphrase, 0, len);
+ munlock(gpg.passphrase, len);
+ g_free(gpg.passphrase);
+ }
+ if (passphrase) {
+ gpg.passphrase = g_strdup(passphrase);
+ mlock(gpg.passphrase, strlen(gpg.passphrase));
+ } else {
+ gpg.passphrase = NULL;
+ }
+}
+
+// gpg_set_private_key(keyid)
+// Set the current private key id (use NULL to unset it).
+void gpg_set_private_key(const char *priv_keyid)
+{
+ g_free(gpg.private_key);
+ if (priv_keyid)
+ gpg.private_key = g_strdup(priv_keyid);
+ else
+ gpg.private_key = NULL;
+}
+
+// strip_header_footer(data)
+// Remove PGP header & footer from data.
+// Return a new string, or NULL.
+// The string must be freed by the caller with g_free() when no longer needed.
+static char *strip_header_footer(const char *data)
+{
+ char *p, *q;
+
+ if (!data)
+ return NULL;
+
+ // p: beginning of real data
+ // q: end of real data
+
+ // Strip header (to the first empty line)
+ p = strstr(data, "\n\n");
+ if (!p)
+ return g_strdup(data);
+
+ // Strip footer
+ // We want to remove the last lines, until the line beginning with a '-'
+ p += 2;
+ for (q = p ; *q; q++) ;
+ // (q is at the end of data now)
+ for (q--; q > p && (*q != '\n' || *(q+1) != '-'); q--) ;
+
+ if (q <= p)
+ return NULL; // Shouldn't happen...
+
+ return g_strndup(p, q-p);
+}
+
+// passphrase_cb()
+// GPGME passphrase callback function.
+static gpgme_error_t passphrase_cb(void *hook, const char *uid_hint,
+ const char *passphrase_info, int prev_was_bad, int fd)
+{
+ ssize_t len;
+
+ // Abort if we do not have the password.
+ if (!gpg.passphrase) {
+ write(fd, "\n", 1);
+ return gpg_error(GPG_ERR_CANCELED);
+ }
+
+ // Write the passphrase to the file descriptor.
+ len = strlen(gpg.passphrase);
+ if (write(fd, gpg.passphrase, len) != len)
+ return gpg_error(GPG_ERR_CANCELED);
+ if (write(fd, "\n", 1) != 1)
+ return gpg_error(GPG_ERR_CANCELED);
+
+ return 0; // Success
+}
+
+// gpg_verify(gpg_data, text, *sigsum)
+// Verify that gpg_data is a correct signature for text.
+// Return the key id (or fingerprint), and set *sigsum to
+// the gpgme signature summary value.
+// The returned string must be freed with g_free() after use.
+char *gpg_verify(const char *gpg_data, const char *text,
+ gpgme_sigsum_t *sigsum)
+{
+ gpgme_ctx_t ctx;
+ gpgme_data_t data_sign, data_text;
+ char *data;
+ char *verified_key = NULL;
+ gpgme_key_t key;
+ gpgme_error_t err;
+ const char prefix[] = "-----BEGIN PGP SIGNATURE-----\n\n";
+ const char suffix[] = "\n-----END PGP SIGNATURE-----\n";
+
+ // Reset the summary.
+ *sigsum = 0;
+
+ if (!gpg.enabled)
+ return NULL;
+
+ err = gpgme_new(&ctx);
+ if (err) {
+ scr_LogPrint(LPRINT_LOGNORM|LPRINT_NOTUTF8,
+ "GPGME error: %s", gpgme_strerror(err));
+ return NULL;
+ }
+
+ gpgme_set_protocol(ctx, GPGME_PROTOCOL_OpenPGP);
+
+ // Surround the given data with the prefix & suffix
+ data = g_new(char, sizeof(prefix) + sizeof(suffix) + strlen(gpg_data));
+ strcpy(data, prefix);
+ strcat(data, gpg_data);
+ strcat(data, suffix);
+
+ err = gpgme_data_new_from_mem(&data_sign, data, strlen(data), 0);
+ if (!err) {
+ err = gpgme_data_new_from_mem(&data_text, text, strlen(text), 0);
+ if (!err) {
+ err = gpgme_op_verify(ctx, data_sign, data_text, 0);
+ if (!err) {
+ gpgme_verify_result_t vr = gpgme_op_verify_result(ctx);
+ if (vr && vr->signatures) {
+ char *r = vr->signatures->fpr;
+ // Found the fingerprint. Let's try to get the key id.
+ if(!gpgme_get_key(ctx, r, &key, 0)) {
+ r = key->subkeys->keyid;
+ gpgme_key_release(key);
+ }
+ // r is a static variable, let's copy it.
+ verified_key = g_strdup(r);
+ *sigsum = vr->signatures->summary;
+ }
+ }
+ gpgme_data_release(data_text);
+ }
+ gpgme_data_release(data_sign);
+ }
+ if (err)
+ scr_LogPrint(LPRINT_LOGNORM|LPRINT_NOTUTF8,
+ "GPGME error: %s", gpgme_strerror(err));
+ gpgme_release(ctx);
+ g_free(data);
+ return verified_key;
+}
+
+// gpg_sign(gpg_data)
+// Return a signature of gpg_data (or NULL).
+// The returned string must be freed with g_free() after use.
+char *gpg_sign(const char *gpg_data)
+{
+ gpgme_ctx_t ctx;
+ gpgme_data_t in, out;
+ char *p;
+ char *signed_data = NULL;
+ size_t nread;
+ gpgme_key_t key;
+ gpgme_error_t err;
+
+ if (!gpg.enabled || !gpg.private_key)
+ return NULL;
+
+ err = gpgme_new(&ctx);
+ if (err) {
+ scr_LogPrint(LPRINT_LOGNORM|LPRINT_NOTUTF8,
+ "GPGME error: %s", gpgme_strerror(err));
+ return NULL;
+ }
+
+ gpgme_set_protocol(ctx, GPGME_PROTOCOL_OpenPGP);
+ gpgme_set_textmode(ctx, 0);
+ gpgme_set_armor(ctx, 1);
+
+ p = getenv("GPG_AGENT_INFO");
+ if (!(p && strchr(p, ':')))
+ gpgme_set_passphrase_cb(ctx, passphrase_cb, 0);
+
+ err = gpgme_get_key(ctx, gpg.private_key, &key, 1);
+ if (!err) {
+ gpgme_signers_clear(ctx);
+ gpgme_signers_add(ctx, key);
+ gpgme_key_release(key);
+ err = gpgme_data_new_from_mem(&in, gpg_data, strlen(gpg_data), 0);
+ }
+ if (!err) {
+ err = gpgme_data_new(&out);
+ if (!err) {
+ err = gpgme_op_sign(ctx, in, out, GPGME_SIG_MODE_DETACH);
+ if (!err) {
+ signed_data = gpgme_data_release_and_get_mem(out, &nread);
+ if (signed_data) {
+ // We need to add a trailing NULL
+ char *dd = g_strndup(signed_data, nread);
+ free(signed_data);
+ signed_data = strip_header_footer(dd);
+ g_free(dd);
+ }
+ } else {
+ gpgme_data_release(out);
+ }
+ }
+ gpgme_data_release(in);
+ }
+ if (err && err != GPG_ERR_CANCELED)
+ scr_LogPrint(LPRINT_LOGNORM|LPRINT_NOTUTF8,
+ "GPGME error: %s", gpgme_strerror(err));
+ gpgme_release(ctx);
+ return signed_data;
+}
+
+// gpg_decrypt(gpg_data)
+// Return decrypted gpg_data (or NULL).
+// The returned string must be freed with g_free() after use.
+char *gpg_decrypt(const char *gpg_data)
+{
+ gpgme_ctx_t ctx;
+ gpgme_data_t in, out;
+ char *p, *data;
+ char *decrypted_data = NULL;
+ size_t nread;
+ gpgme_error_t err;
+ const char prefix[] = "-----BEGIN PGP MESSAGE-----\n\n";
+ const char suffix[] = "\n-----END PGP MESSAGE-----\n";
+
+ if (!gpg.enabled)
+ return NULL;
+
+ err = gpgme_new(&ctx);
+ if (err) {
+ scr_LogPrint(LPRINT_LOGNORM|LPRINT_NOTUTF8,
+ "GPGME error: %s", gpgme_strerror(err));
+ return NULL;
+ }
+
+ gpgme_set_protocol(ctx, GPGME_PROTOCOL_OpenPGP);
+
+ p = getenv("GPG_AGENT_INFO");
+ if (!(p && strchr(p, ':')))
+ gpgme_set_passphrase_cb(ctx, passphrase_cb, 0);
+
+ // Surround the given data with the prefix & suffix
+ data = g_new(char, sizeof(prefix) + sizeof(suffix) + strlen(gpg_data));
+ strcpy(data, prefix);
+ strcat(data, gpg_data);
+ strcat(data, suffix);
+
+ err = gpgme_data_new_from_mem(&in, data, strlen(data), 0);
+ if (!err) {
+ err = gpgme_data_new(&out);
+ if (!err) {
+ err = gpgme_op_decrypt(ctx, in, out);
+ if (!err) {
+ decrypted_data = gpgme_data_release_and_get_mem(out, &nread);
+ if (decrypted_data) {
+ // We need to add a trailing NULL
+ char *dd = g_strndup(decrypted_data, nread);
+ free(decrypted_data);
+ decrypted_data = dd;
+ }
+ } else {
+ gpgme_data_release(out);
+ }
+ }
+ gpgme_data_release(in);
+ }
+ if (err && err != GPG_ERR_CANCELED)
+ scr_LogPrint(LPRINT_LOGNORM|LPRINT_NOTUTF8,
+ "GPGME error: %s", gpgme_strerror(err));
+ gpgme_release(ctx);
+ g_free(data);
+ return decrypted_data;
+}
+
+// gpg_encrypt(gpg_data, keyid)
+// Return encrypted gpg_data with the key keyid (or NULL).
+// The returned string must be freed with g_free() after use.
+char *gpg_encrypt(const char *gpg_data, const char *keyid)
+{
+ gpgme_ctx_t ctx;
+ gpgme_data_t in, out;
+ char *encrypted_data = NULL, *edata;
+ size_t nread;
+ gpgme_key_t key;
+ gpgme_error_t err;
+
+ if (!gpg.enabled)
+ return NULL;
+
+ err = gpgme_new(&ctx);
+ if (err) {
+ scr_LogPrint(LPRINT_LOGNORM|LPRINT_NOTUTF8,
+ "GPGME error: %s", gpgme_strerror(err));
+ return NULL;
+ }
+
+ gpgme_set_protocol(ctx, GPGME_PROTOCOL_OpenPGP);
+ gpgme_set_textmode(ctx, 0);
+ gpgme_set_armor(ctx, 1);
+
+ err = gpgme_get_key(ctx, keyid, &key, 0);
+ if (!err) {
+ gpgme_key_t keys[] = { key, 0 };
+ err = gpgme_data_new_from_mem(&in, gpg_data, strlen(gpg_data), 0);
+ if (!err) {
+ err = gpgme_data_new(&out);
+ if (!err) {
+ err = gpgme_op_encrypt(ctx, keys, GPGME_ENCRYPT_ALWAYS_TRUST, in, out);
+ if (!err)
+ encrypted_data = gpgme_data_release_and_get_mem(out, &nread);
+ else
+ gpgme_data_release(out);
+ }
+ gpgme_data_release(in);
+ }
+ gpgme_key_release(key);
+ }
+ if (err && err != GPG_ERR_CANCELED)
+ scr_LogPrint(LPRINT_LOGNORM|LPRINT_NOTUTF8,
+ "GPGME error: %s", gpgme_strerror(err));
+ gpgme_release(ctx);
+ edata = strip_header_footer(encrypted_data);
+ if (encrypted_data)
+ free(encrypted_data);
+ return edata;
+}
+
+// gpg_test_passphrase()
+// Test the current gpg.passphrase with gpg.private_key.
+// If the test doesn't succeed, the passphrase is cleared and a non-null
+// value is returned.
+int gpg_test_passphrase(void)
+{
+ char *s;
+
+ if (!gpg.private_key)
+ return -1; // No private key...
+
+ s = gpg_sign("test");
+ if (s) {
+ free(s);
+ return 0; // Ok, test successful
+ }
+ // The passphrase is wrong (if provided)
+ gpg_set_passphrase(NULL);
+ return -1;
+}
+
+inline int gpg_enabled(void)
+{
+ return gpg.enabled;
+}
+
+#else /* not HAVE_GPGME */
+
+inline int gpg_enabled(void)
+{
+ return 0;
+}
+
+#endif /* HAVE_GPGME */
+
+/* vim: set expandtab cindent cinoptions=>2\:2(0: For Vim users... */