/*
* gpg.c
* vim: expandtab:ts=4:sts=4:sw=4
*
* Copyright (C) 2012 - 2019 James Booth <boothj5@gmail.com>
* Copyright (C) 2018 - 2022 Michael Vetter <jubalh@iodoru.org>
*
* This file is part of Profanity.
*
* Profanity 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 3 of the License, or
* (at your option) any later version.
*
* Profanity 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 Profanity. If not, see <https://www.gnu.org/licenses/>.
*
* In addition, as a special exception, the copyright holders give permission to
* link the code of portions of this program with the OpenSSL library under
* certain conditions as described in each individual source file, and
* distribute linked combinations including the two.
*
* You must obey the GNU General Public License in all respects for all of the
* code used other than OpenSSL. If you modify file(s) with this exception, you
* may extend this exception to your version of the file(s), but you are not
* obligated to do so. If you do not wish to do so, delete this exception
* statement from your version. If you delete this exception statement from all
* source files in the program, then also delete it here.
*
*/
#include "config.h"
#include <locale.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <sys/stat.h>
#include <glib.h>
#include <glib/gstdio.h>
#include <gpgme.h>
#include "log.h"
#include "common.h"
#include "pgp/gpg.h"
#include "config/files.h"
#include "tools/autocomplete.h"
#include "ui/ui.h"
#define PGP_SIGNATURE_HEADER "-----BEGIN PGP SIGNATURE-----"
#define PGP_SIGNATURE_FOOTER "-----END PGP SIGNATURE-----"
#define PGP_MESSAGE_HEADER "-----BEGIN PGP MESSAGE-----"
#define PGP_MESSAGE_FOOTER "-----END PGP MESSAGE-----"
static const char* libversion = NULL;
static GHashTable* pubkeys;
static gchar* pubsloc;
static GKeyFile* pubkeyfile;
static char* passphrase;
static char* passphrase_attempt;
static Autocomplete key_ac;
static char* _remove_header_footer(char* str, const char* const footer);
static char* _add_header_footer(const char* const str, const char* const header, const char* const footer);
static void _save_pubkeys(void);
void
_p_gpg_free_pubkeyid(ProfPGPPubKeyId* pubkeyid)
{
if (pubkeyid) {
free(pubkeyid->id);
}
free(pubkeyid);
}
static gpgme_error_t*
_p_gpg_passphrase_cb(void* hook, const char* uid_hint, const char* passphrase_info, int prev_was_bad, int fd)
{
if (passphrase) {
gpgme_io_write(fd, passphrase, strlen(passphrase));
} else {
GString* pass_term = g_string_new("");
char* password = ui_ask_pgp_passphrase(uid_hint, prev_was_bad);
if (password) {
g_string_append(pass_term, password);
free(password);
}
g_string_append(pass_term, "\n");
if (passphrase_attempt) {
free(passphrase_attempt);
}
passphrase_attempt = pass_term->str;
g_string_free(pass_term, FALSE);
gpgme_io_write(fd, passphrase_attempt, strlen(passphrase_attempt));
}
return 0;
}
void
p_gpg_init(void)
{
libversion = gpgme_check_version(NULL);
log_debug("GPG: Found gpgme version: %s", libversion);
gpgme_set_locale(NULL, LC_CTYPE, setlocale(LC_CTYPE, NULL));
pubkeys = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, (GDestroyNotify)_p_gpg_free_pubkeyid);
key_ac = autocomplete_new();
GHashTable* keys = p_gpg_list_keys();
p_gpg_free_keys(keys);
passphrase = NULL;
passphrase_attempt = NULL;
}
void
p_gpg_close(void)
{
if (pubkeys) {
g_hash_table_destroy(pubkeys);
pubkeys = NULL;
}
if (pubkeyfile) {
g_key_file_free(pubkeyfile);
pubkeyfile = NULL;
}
free(pubsloc);
pubsloc = NULL;
autocomplete_free(key_ac);
key_ac = NULL;
if (passphrase) {
free(passphrase);
passphrase = NULL;
}
if (passphrase_attempt) {
free(passphrase_attempt);
passphrase_attempt = NULL;
}
}
void
p_gpg_on_connect(const char* const barejid)
{
pubsloc = files_file_in_account_data_path(DIR_PGP, barejid, "pubkeys");
if (!pubsloc) {
log_error("Could not create directory for account %s.", barejid);
cons_show_error("Could not create directory for account %s.", barejid);
return;
}
if (g_file_test(pubsloc, G_FILE_TEST_EXISTS)) {
g_chmod(pubsloc, S_IRUSR | S_IWUSR);
}
pubkeyfile = g_key_file_new();
g_key_file_load_from_file(pubkeyfile, pubsloc, G_KEY_FILE_KEEP_COMMENTS, NULL);
// load each keyid
gsize len = 0;
gchar** jids = g_key_file_get_groups(pubkeyfile, &len);
gpgme_ctx_t ctx;
gpgme_error_t error = gpgme_new(&ctx);
if (error) {
log_error("GPG: Failed to create gpgme context. %s %s", gpgme_strsource(error), gpgme_strerror(error));
g_strfreev(jids);
return;
}
for (int i = 0; i < len; i++) {
GError* gerr = NULL;
gchar* jid = jids[i];
gchar* keyid = g_key_file_get_string(pubkeyfile, jid, "keyid", &gerr);
if (gerr) {
log_error("Error loading PGP key id for %s", jid);
g_error_free(gerr);
g_free(keyid);
} else {
gpgme_key_t key = NULL;
error = gpgme_get_key(ctx, keyid, &key, 0);
if (error || key == NULL) {
log_warning("GPG: Failed to get key for %s: %s %s", jid, gpgme_strsource(error), gpgme_strerror(error));
continue;
}
ProfPGPPubKeyId* pubkeyid = malloc(sizeof(ProfPGPPubKeyId));
pubkeyid->id = strdup(keyid);
pubkeyid->received = FALSE;
g_hash_table_replace(pubkeys, strdup(jid), pubkeyid);
g_free(keyid);
gpgme_key_unref(key);
}
}
gpgme_release(ctx);
g_strfreev(jids);
_save_pubkeys();
}
void
p_gpg_on_disconnect(void)
{
if (pubkeys) {
g_hash_table_destroy(pubkeys);
pubkeys = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, (GDestroyNotify)_p_gpg_free_pubkeyid);
}
if (pubkeyfile) {
g_key_file_free(pubkeyfile);
pubkeyfile = NULL;
}
free(pubsloc);
pubsloc = NULL;
if (passphrase) {
free(passphrase);
passphrase = NULL;
}
if (passphrase_attempt) {
free(passphrase_attempt);
passphrase_attempt = NULL;
}
}
gboolean
p_gpg_addkey(const char* const jid, const char* const keyid)
{
gpgme_ctx_t ctx;
gpgme_error_t error = gpgme_new(&ctx);
if (error) {
log_error("GPG: Failed to create gpgme context. %s %s", gpgme_strsource(error), gpgme_strerror(error));
return FALSE;
}
gpgme_key_t key = NULL;
error = gpgme_get_key(ctx, keyid, &key, 0);
gpgme_release(ctx);
if (error || key == NULL) {
log_error("GPG: Failed to get key. %s %s", gpgme_strsource(error), gpgme_strerror(error));
return FALSE;
}
// save to public key file
g_key_file_set_string(pubkeyfile, jid, "keyid", keyid);
_save_pubkeys();
// update in memory pubkeys list
ProfPGPPubKeyId* pubkeyid = malloc(sizeof(ProfPGPPubKeyId));
pubkeyid->id = strdup(keyid);
pubkeyid->received = FALSE;
g_hash_table_replace(pubkeys, strdup(jid), pubkeyid);
gpgme_key_unref(key);
return TRUE;
}
ProfPGPKey*
p_gpg_key_new(void)
{
ProfPGPKey* p_pgpkey = malloc(sizeof(ProfPGPKey));
p_pgpkey->id = NULL;
p_pgpkey->name = NULL;
p_pgpkey->fp = NULL;
p_pgpkey->encrypt = FALSE;
p_pgpkey->sign = FALSE;
p_pgpkey->certify = FALSE;
p_pgpkey->authenticate = FALSE;
p_pgpkey->secret = FALSE;
return p_pgpkey;
}
void
p_gpg_free_key(ProfPGPKey* key)
{
if (key) {
free(key->id);
free(key->name);
free(key->fp);
free(key);
}
}
GHashTable*
p_gpg_list_keys(void)
{
gpgme_error_t error;
GHashTable* result = g_hash_table_new_full(g_str_hash, g_str_equal, free, (GDestroyNotify)p_gpg_free_key);
gpgme_ctx_t ctx;
error = gpgme_new(&ctx);
if (error) {
log_error("GPG: Could not list keys. %s %s", gpgme_strsource(error), gpgme_strerror(error));
return NULL;
}
error = gpgme_op_keylist_start(ctx, NULL, 0);
if (error == GPG_ERR_NO_ERROR) {
gpgme_key_t key;
error = gpgme_op_keylist_next(ctx, &key);
while (!error) {
gpgme_subkey_t sub = key->subkeys;
ProfPGPKey* p_pgpkey = p_gpg_key_new();
p_pgpkey->id = strdup(sub->keyid);
p_pgpkey->name = strdup(key->uids->uid);
p_pgpkey->fp = strdup(sub->fpr);
if (sub->can_encrypt)
p_pgpkey->encrypt = TRUE;
if (sub->can_authenticate)
p_pgpkey->authenticate = TRUE;
if (sub->can_certify)
p_pgpkey->certify = TRUE;
if (sub->can_sign)
p_pgpkey->sign = TRUE;
sub = sub->next;
while (sub) {
if (sub->can_encrypt)
p_pgpkey->encrypt = TRUE;
if (sub->can_authenticate)
p_pgpkey->authenticate = TRUE;
if (sub->can_certify)
p_pgpkey->certify = TRUE;
if (sub->can_sign)
p_pgpkey->sign = TRUE;
sub = sub->next;
}
g_hash_table_insert(result, strdup(p_pgpkey->name), p_pgpkey);
gpgme_key_unref(key);
error = gpgme_op_keylist_next(ctx, &key);
}
}
error = gpgme_op_keylist_start(ctx, NULL, 1);
if (error == GPG_ERR_NO_ERROR) {
gpgme_key_t key;
error = gpgme_op_keylist_next(ctx, &key);
while (!error) {
gpgme_subkey_t sub = key->subkeys;
while (sub) {
if (sub->secret) {
ProfPGPKey* p_pgpkey = g_hash_table_lookup(result, key->uids->uid);
if (p_pgpkey) {
p_pgpkey->secret = TRUE;
}
}
sub = sub->next;
}
gpgme_key_unref(key);
error = gpgme_op_keylist_next(ctx, &key);
}
}
gpgme_release(ctx);
autocomplete_clear(key_ac);
GList* ids = g_hash_table_get_keys(result);
GList* curr = ids;
while (curr) {
ProfPGPKey* key = g_hash_table_lookup(result, curr->data);
autocomplete_add(key_ac, key->id);
curr = curr->next;
}
g_list_free(ids);
return result;
}
void
p_gpg_free_keys(GHashTable* keys)
{
g_hash_table_destroy(keys);
}
GHashTable*
p_gpg_pubkeys(void)
{
return pubkeys;
}
const char*
p_gpg_libver(void)
{
if (libversion == NULL) {
libversion = gpgme_check_version(NULL);
}
return libversion;
}
gboolean
p_gpg_valid_key(const char* const keyid, char** err_str)
{
gpgme_ctx_t ctx;
gpgme_error_t error = gpgme_new(&ctx);
if (error) {
log_error("GPG: Failed to create gpgme context. %s %s", gpgme_strsource(error), gpgme_strerror(error));
*err_str = strdup(gpgme_strerror(error));
return FALSE;
}
gpgme_key_t key = NULL;
error = gpgme_get_key(ctx, keyid, &key, 1);
if (error || key == NULL) {
log_error("GPG: Failed to get key. %s %s", gpgme_strsource(error), gpgme_strerror(error));
*err_str = strdup(gpgme_strerror(error));
gpgme_release(ctx);
return FALSE;
}
if (key == NULL) {
*err_str = strdup("Unknown error");
gpgme_release(ctx);
return FALSE;
}
gpgme_release(ctx);
gpgme_key_unref(key);
return TRUE;
}
gboolean
p_gpg_available(const char* const barejid)
{
char* pubkey = g_hash_table_lookup(pubkeys, barejid);
return (pubkey != NULL);
}
void
p_gpg_verify(const char* const barejid, const char* const sign)
{
if (!sign) {
return;
}
gpgme_ctx_t ctx;
gpgme_error_t error = gpgme_new(&ctx);
if (error) {
log_error("GPG: Failed to create gpgme context. %s %s", gpgme_strsource(error), gpgme_strerror(error));
return;
}
char* sign_with_header_footer = _add_header_footer(sign, PGP_SIGNATURE_HEADER, PGP_SIGNATURE_FOOTER);
gpgme_data_t sign_data;
gpgme_data_new_from_mem(&sign_data, sign_with_header_footer, strlen(sign_with_header_footer), 1);
free(sign_with_header_footer);
gpgme_data_t plain_data;
gpgme_data_new(&plain_data);
error = gpgme_op_verify(ctx, sign_data, NULL, plain_data);
gpgme_data_release(sign_data);
gpgme_data_release(plain_data);
if (error) {
log_error("GPG: Failed to verify. %s %s", gpgme_strsource(error), gpgme_strerror(error));
gpgme_release(ctx);
return;
}
gpgme_verify_result_t result = gpgme_op_verify_result(ctx);
if (result) {
if (result->signatures) {
gpgme_key_t key = NULL;
error = gpgme_get_key(ctx, result->signatures->fpr, &key, 0);
if (error) {
log_debug("Could not find PGP key with ID %s for %s", result->signatures->fpr, barejid);
} else {
log_debug("Fingerprint found for %s: %s ", barejid, key->subkeys->fpr);
ProfPGPPubKeyId* pubkeyid = malloc(sizeof(ProfPGPPubKeyId));
pubkeyid->id = strdup(key->subkeys->keyid);
pubkeyid->received = TRUE;
g_hash_table_replace(pubkeys, strdup(barejid), pubkeyid);
}
gpgme_key_unref(key);
}
}
gpgme_release(ctx);
}
char*
p_gpg_sign(const char* const str, const char* const fp)
{
gpgme_ctx_t ctx;
gpgme_error_t error = gpgme_new(&ctx);
if (error) {
log_error("GPG: Failed to create gpgme context. %s %s", gpgme_strsource(error), gpgme_strerror(error));
return NULL;
}
gpgme_set_passphrase_cb(ctx, (gpgme_passphrase_cb_t)_p_gpg_passphrase_cb, NULL);
gpgme_key_t key = NULL;
error = gpgme_get_key(ctx, fp, &key, 1);
if (error || key == NULL) {
log_error("GPG: Failed to get key. %s %s", gpgme_strsource(error), gpgme_strerror(error));
gpgme_release(ctx);
return NULL;
}
gpgme_signers_clear(ctx);
error = gpgme_signers_add(ctx, key);
gpgme_key_unref(key);
if (error) {
log_error("GPG: Failed to load signer. %s %s", gpgme_strsource(error), gpgme_strerror(error));
gpgme_release(ctx);
return NULL;
}
char* str_or_empty = NULL;
if (str) {
str_or_empty = strdup(str);
} else {
str_or_empty = strdup("");
}
gpgme_data_t str_data;
gpgme_data_new_from_mem(&str_data, str_or_empty, strlen(str_or_empty), 1);
free(str_or_empty);
gpgme_data_t signed_data;
gpgme_data_new(&signed_data);
gpgme_set_armor(ctx, 1);
error = gpgme_op_sign(ctx, str_data, signed_data, GPGME_SIG_MODE_DETACH);
gpgme_data_release(str_data);
gpgme_release(ctx);
if (error) {
log_error("GPG: Failed to sign string. %s %s", gpgme_strsource(error), gpgme_strerror(error));
gpgme_data_release(signed_data);
return NULL;
}
char* result = NULL;
size_t len = 0;
char* signed_str = gpgme_data_release_and_get_mem(signed_data, &len);
if (signed_str) {
GString* signed_gstr = g_string_new("");
g_string_append_len(signed_gstr, signed_str, len);
result = _remove_header_footer(signed_gstr->str, PGP_SIGNATURE_FOOTER);
g_string_free(signed_gstr, TRUE);
gpgme_free(signed_str);
}
if (passphrase_attempt) {
passphrase = strdup(passphrase_attempt);
}
return result;
}
char*
p_gpg_encrypt(const char* const barejid, const char* const message, const char* const fp)
{
ProfPGPPubKeyId* pubkeyid = g_hash_table_lookup(pubkeys, barejid);
if (!pubkeyid) {
return NULL;
}
if (!pubkeyid->id) {
return NULL;
}
gpgme_key_t keys[3];
keys[0] = NULL;
keys[1] = NULL;
keys[2] = NULL;
gpgme_ctx_t ctx;
gpgme_error_t error = gpgme_new(&ctx);
if (error) {
log_error("GPG: Failed to create gpgme context. %s %s", gpgme_strsource(error), gpgme_strerror(error));
return NULL;
}
gpgme_key_t receiver_key;
error = gpgme_get_key(ctx, pubkeyid->id, &receiver_key, 0);
if (error || receiver_key == NULL) {
log_error("GPG: Failed to get receiver_key. %s %s", gpgme_strsource(error), gpgme_strerror(error));
gpgme_release(ctx);
return NULL;
}
keys[0] = receiver_key;
gpgme_key_t sender_key = NULL;
error = gpgme_get_key(ctx, fp, &sender_key, 0);
if (error || sender_key == NULL) {
log_error("GPG: Failed to get sender_key. %s %s", gpgme_strsource(error), gpgme_strerror(error));
gpgme_release(ctx);
return NULL;
}
keys[1] = sender_key;
gpgme_data_t plain;
gpgme_data_new_from_mem(&plain, message, strlen(message), 1);
gpgme_data_t cipher;
gpgme_data_new(&cipher);
gpgme_set_armor(ctx, 1);
error = gpgme_op_encrypt(ctx, keys, GPGME_ENCRYPT_ALWAYS_TRUST, plain, cipher);
gpgme_data_release(plain);
gpgme_release(ctx);
gpgme_key_unref(receiver_key);
gpgme_key_unref(sender_key);
if (error) {
log_error("GPG: Failed to encrypt message. %s %s", gpgme_strsource(error), gpgme_strerror(error));
return NULL;
}
size_t len;
char* cipher_str = gpgme_data_release_and_get_mem(cipher, &len);
char* result = NULL;
if (cipher_str) {
GString* cipher_gstr = g_string_new("");
g_string_append_len(cipher_gstr, cipher_str, len);
result = _remove_header_footer(cipher_gstr->str, PGP_MESSAGE_FOOTER);
g_string_free(cipher_gstr, TRUE);
gpgme_free(cipher_str);
}
return result;
}
char*
p_gpg_decrypt(const char* const cipher)
{
gpgme_ctx_t ctx;
gpgme_error_t error = gpgme_new(&ctx);
if (error) {
log_error("GPG: Failed to create gpgme context. %s %s", gpgme_strsource(error), gpgme_strerror(error));
return NULL;
}
gpgme_set_passphrase_cb(ctx, (gpgme_passphrase_cb_t)_p_gpg_passphrase_cb, NULL);
char* cipher_with_headers = _add_header_footer(cipher, PGP_MESSAGE_HEADER, PGP_MESSAGE_FOOTER);
gpgme_data_t cipher_data;
gpgme_data_new_from_mem(&cipher_data, cipher_with_headers, strlen(cipher_with_headers), 1);
free(cipher_with_headers);
gpgme_data_t plain_data;
gpgme_data_new(&plain_data);
error = gpgme_op_decrypt(ctx, cipher_data, plain_data);
gpgme_data_release(cipher_data);
if (error) {
log_error("GPG: Failed to encrypt message. %s %s", gpgme_strsource(error), gpgme_strerror(error));
gpgme_data_release(plain_data);
gpgme_release(ctx);
return NULL;
}
gpgme_decrypt_result_t res = gpgme_op_decrypt_result(ctx);
if (res) {
GString* recipients_str = g_string_new("");
gpgme_recipient_t recipient = res->recipients;
while (recipient) {
gpgme_key_t key;
error = gpgme_get_key(ctx, recipient->keyid, &key, 1);
if (!error && key) {
const char* addr = gpgme_key_get_string_attr(key, GPGME_ATTR_EMAIL, NULL, 0);
if (addr) {
g_string_append(recipients_str, addr);
}
gpgme_key_unref(key);
}
if (recipient->next) {
g_string_append(recipients_str, ", ");
}
recipient = recipient->next;
}
log_debug("GPG: Decrypted message for recipients: %s", recipients_str->str);
g_string_free(recipients_str, TRUE);
}
gpgme_release(ctx);
size_t len = 0;
char* plain_str = gpgme_data_release_and_get_mem(plain_data, &len);
char* result = NULL;
if (plain_str) {
plain_str[len] = 0;
result = g_strdup(plain_str);
}
gpgme_free(plain_str);
if (passphrase_attempt) {
passphrase = strdup(passphrase_attempt);
}
return result;
}
void
p_gpg_free_decrypted(char* decrypted)
{
g_free(decrypted);
}
char*
p_gpg_autocomplete_key(const char* const search_str, gboolean previous, void* context)
{
return autocomplete_complete(key_ac, search_str, TRUE, previous);
}
void
p_gpg_autocomplete_key_reset(void)
{
autocomplete_reset(key_ac);
}
char*
p_gpg_format_fp_str(char* fp)
{
if (!fp) {
return NULL;
}
GString* format = g_string_new("");
int len = strlen(fp);
for (int i = 0; i < len; i++) {
g_string_append_c(format, fp[i]);
if (((i + 1) % 4 == 0) && (i + 1 < len)) {
g_string_append_c(format, ' ');
}
}
char* result = format->str;
g_string_free(format, FALSE);
return result;
}
static char*
_remove_header_footer(char* str, const char* const footer)
{
int pos = 0;
int newlines = 0;
while (newlines < 2) {
if (str[pos] == '\n') {
newlines++;
}
pos++;
if (str[pos] == '\0') {
return NULL;
}
}
char* stripped = strdup(&str[pos]);
char* footer_start = g_strrstr(stripped, footer);
footer_start[0] = '\0';
return stripped;
}
static char*
_add_header_footer(const char* const str, const char* const header, const char* const footer)
{
GString* result_str = g_string_new("");
g_string_append(result_str, header);
g_string_append(result_str, "\n\n");
g_string_append(result_str, str);
g_string_append(result_str, "\n");
g_string_append(result_str, footer);
char* result = result_str->str;
g_string_free(result_str, FALSE);
return result;
}
static void
_save_pubkeys(void)
{
gsize g_data_size;
gchar* g_pubkeys_data = g_key_file_to_data(pubkeyfile, &g_data_size, NULL);
g_file_set_contents(pubsloc, g_pubkeys_data, g_data_size, NULL);
g_chmod(pubsloc, S_IRUSR | S_IWUSR);
g_free(g_pubkeys_data);
}