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Diffstat (limited to 'src/pgp/ox.c')
| -rw-r--r-- | src/pgp/ox.c | 574 |
1 files changed, 574 insertions, 0 deletions
diff --git a/src/pgp/ox.c b/src/pgp/ox.c new file mode 100644 index 00000000..a7cdfabb --- /dev/null +++ b/src/pgp/ox.c @@ -0,0 +1,574 @@ +/* + * ox.c + * vim: expandtab:ts=4:sts=4:sw=4 + * + * Copyright (C) 2020 Stefan Kropp <stefan@debxwoody.de> + * Copyright (C) 2020 - 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/ox.h" +#include "config/files.h" +#include "ui/ui.h" + +static gpgme_key_t _ox_key_lookup(const char* const barejid, gboolean secret_only); +static gboolean _ox_key_is_usable(gpgme_key_t key, const char* const barejid, gboolean secret); + +/*! + * \brief Public keys with XMPP-URI. + * + * This function will look for all public key with a XMPP-URI as UID. + * + * @returns GHashTable* with GString* xmpp-uri and ProfPGPKey* value. Empty + * hash, if there is no key. NULL in case of error. + * + */ +GHashTable* +ox_gpg_public_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("OX: Failed to create gpgme context. %s %s", gpgme_strsource(error), gpgme_strerror(error)); + return NULL; + } + + error = gpgme_op_keylist_start(ctx, NULL, 0); // all public keys + if (error == GPG_ERR_NO_ERROR) { + gpgme_key_t key; + error = gpgme_op_keylist_next(ctx, &key); + if (error != GPG_ERR_EOF && error != GPG_ERR_NO_ERROR) { + log_error("OX: gpgme_op_keylist_next %s %s", gpgme_strsource(error), gpgme_strerror(error)); + g_hash_table_destroy(result); + return NULL; + } + while (!error) { + // Looking for XMPP URI UID + gpgme_user_id_t uid = key->uids; + gpgme_user_id_t xmppid = NULL; + while (!xmppid && uid) { + if (uid->name && strlen(uid->name) >= 10) { + if (strstr(uid->name, "xmpp:") == uid->name) { + xmppid = uid; + } + } + uid = uid->next; + } + + if (xmppid) { + // Build Key information about all subkey + gpgme_subkey_t sub = key->subkeys; + + ProfPGPKey* p_pgpkey = p_gpg_key_new(); + p_pgpkey->id = strdup(sub->keyid); + p_pgpkey->name = strdup(xmppid->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); + } + } + gpgme_release(ctx); + + return result; +} + +char* +p_ox_gpg_signcrypt(const char* const sender_barejid, const char* const recipient_barejid, const char* const message) +{ + setlocale(LC_ALL, ""); + gpgme_check_version(NULL); + gpgme_set_locale(NULL, LC_CTYPE, setlocale(LC_CTYPE, NULL)); + gpgme_ctx_t ctx; + + gpgme_error_t error = gpgme_new(&ctx); + if (GPG_ERR_NO_ERROR != error) { + log_error("OX: Failed to create gpgme context. %s %s", gpgme_strsource(error), gpgme_strerror(error)); + return NULL; + } + + error = gpgme_set_protocol(ctx, GPGME_PROTOCOL_OPENPGP); + if (error != 0) { + log_error("OX: Signcrypt error: %s", gpgme_strerror(error)); + } + + gpgme_set_armor(ctx, 0); + gpgme_set_textmode(ctx, 0); + gpgme_set_offline(ctx, 1); + gpgme_set_keylist_mode(ctx, GPGME_KEYLIST_MODE_LOCAL); + if (error != 0) { + log_error("OX: Signcrypt error: %s", gpgme_strerror(error)); + } + + gpgme_key_t recp[3]; + recp[0] = NULL, + recp[1] = NULL; + + char* xmpp_jid_me = alloca((strlen(sender_barejid) + 6) * sizeof(char)); + char* xmpp_jid_recipient = alloca((strlen(recipient_barejid) + 6) * sizeof(char)); + + strcpy(xmpp_jid_me, "xmpp:"); + strcpy(xmpp_jid_recipient, "xmpp:"); + strcat(xmpp_jid_me, sender_barejid); + strcat(xmpp_jid_recipient, recipient_barejid); + + gpgme_signers_clear(ctx); + + // lookup own key + recp[0] = _ox_key_lookup(sender_barejid, TRUE); + if (error != 0) { + cons_show_error("Can't find OX key for %s", xmpp_jid_me); + log_error("OX: Key not found for %s. Error: %s", xmpp_jid_me, gpgme_strerror(error)); + return NULL; + } + + error = gpgme_signers_add(ctx, recp[0]); + if (error != 0) { + log_error("OX: gpgme_signers_add %s. Error: %s", xmpp_jid_me, gpgme_strerror(error)); + return NULL; + } + + // lookup key of recipient + recp[1] = _ox_key_lookup(recipient_barejid, FALSE); + if (error != 0) { + cons_show_error("Can't find OX key for %s", xmpp_jid_recipient); + log_error("OX: Key not found for %s. Error: %s", xmpp_jid_recipient, gpgme_strerror(error)); + return NULL; + } + + recp[2] = NULL; + log_debug("OX: %s <%s>", recp[0]->uids->name, recp[0]->uids->email); + log_debug("OX: %s <%s>", recp[1]->uids->name, recp[1]->uids->email); + + gpgme_encrypt_flags_t flags = 0; + + gpgme_data_t plain; + gpgme_data_t cipher; + + error = gpgme_data_new(&plain); + if (error != 0) { + log_error("OX: %s", gpgme_strerror(error)); + return NULL; + } + + error = gpgme_data_new_from_mem(&plain, message, strlen(message), 0); + if (error != 0) { + log_error("OX: %s", gpgme_strerror(error)); + return NULL; + } + error = gpgme_data_new(&cipher); + if (error != 0) { + log_error("OX: %s", gpgme_strerror(error)); + return NULL; + } + + error = gpgme_op_encrypt_sign(ctx, recp, flags, plain, cipher); + if (error != 0) { + log_error("OX: %s", gpgme_strerror(error)); + return NULL; + } + + size_t len; + char* cipher_str = gpgme_data_release_and_get_mem(cipher, &len); + char* result = g_base64_encode((unsigned char*)cipher_str, len); + gpgme_key_release(recp[0]); + gpgme_key_release(recp[1]); + gpgme_release(ctx); + return result; +} + +gboolean +ox_is_private_key_available(const char* const barejid) +{ + g_assert(barejid); + gboolean result = FALSE; + + gpgme_key_t key = _ox_key_lookup(barejid, TRUE); + if (key) { + if (_ox_key_is_usable(key, barejid, TRUE)) { + result = TRUE; + } + gpgme_key_unref(key); + } + + return result; +} + +gboolean +ox_is_public_key_available(const char* const barejid) +{ + g_assert(barejid); + gboolean result = FALSE; + gpgme_key_t key = _ox_key_lookup(barejid, FALSE); + if (key) { + if (_ox_key_is_usable(key, barejid, FALSE)) { + result = TRUE; + } + gpgme_key_unref(key); + } + return result; +} + +static gpgme_key_t +_ox_key_lookup(const char* const barejid, gboolean secret_only) +{ + g_assert(barejid); + log_debug("OX: Looking for %s key: %s", secret_only == TRUE ? "Private" : "Public", barejid); + gpgme_key_t key = NULL; + gpgme_error_t error; + + gpgme_ctx_t ctx; + error = gpgme_new(&ctx); + + if (error) { + log_error("OX: gpgme_new failed: %s %s", gpgme_strsource(error), gpgme_strerror(error)); + return NULL; + } + + error = gpgme_op_keylist_start(ctx, NULL, secret_only); + if (error == GPG_ERR_NO_ERROR) { + error = gpgme_op_keylist_next(ctx, &key); + if (error != GPG_ERR_EOF && error != GPG_ERR_NO_ERROR) { + log_error("OX: gpgme_op_keylist_next %s %s", gpgme_strsource(error), gpgme_strerror(error)); + return NULL; + } + + GString* xmppuri = g_string_new("xmpp:"); + g_string_append(xmppuri, barejid); + + while (!error) { + // Looking for XMPP URI UID + gpgme_user_id_t uid = key->uids; + + while (uid) { + if (uid->name && strlen(uid->name) >= 10) { + if (g_strcmp0(uid->name, xmppuri->str) == 0) { + gpgme_release(ctx); + return key; + } + } + uid = uid->next; + } + gpgme_key_unref(key); + error = gpgme_op_keylist_next(ctx, &key); + } + } + gpgme_release(ctx); + + return key; +} + +static gboolean +_ox_key_is_usable(gpgme_key_t key, const char* const barejid, gboolean secret) +{ + gboolean result = TRUE; + + if (key->revoked || key->expired || key->disabled) { + cons_show_error("%s's key is revoked, expired or disabled", barejid); + log_info("OX: %s's key is revoked, expired or disabled", barejid); + result = FALSE; + } + + // This might be a nice features but AFAIK is not defined in the XEP. + // If we add this we need to expand our documentation on how to set the + // trust leven in gpg. I'll add an example to this commit body. + /* + if (key->owner_trust < GPGME_VALIDITY_MARGINAL) { + cons_show_error(" %s's key is has a trust level lower than marginal", barejid); + log_info("OX: Owner trust of %s's key is < GPGME_VALIDITY_MARGINAL", barejid); + result = FALSE; + } + */ + + return result; +} + +/*! + * @brief XMPP-OX: Decrypt OX Message. + * + * @param base64 base64_encode OpenPGP message. + * + * @result decrypt XMPP OX Message NULL terminated C-String + */ +char* +p_ox_gpg_decrypt(char* base64) +{ + // if there is no private key avaibale, + // we don't try do decrypt + if (!ox_is_private_key_available(connection_get_barejid())) { + return NULL; + } + setlocale(LC_ALL, ""); + gpgme_check_version(NULL); + gpgme_set_locale(NULL, LC_CTYPE, setlocale(LC_CTYPE, NULL)); + gpgme_ctx_t ctx; + gpgme_error_t error = gpgme_new(&ctx); + + if (GPG_ERR_NO_ERROR != error) { + log_error("OX: gpgme_new failed: %s %s", gpgme_strsource(error), gpgme_strerror(error)); + return NULL; + } + + error = gpgme_set_protocol(ctx, GPGME_PROTOCOL_OPENPGP); + if (error != 0) { + log_error("OX: %s", gpgme_strerror(error)); + } + + gpgme_set_armor(ctx, 0); + gpgme_set_textmode(ctx, 0); + gpgme_set_offline(ctx, 1); + gpgme_set_keylist_mode(ctx, GPGME_KEYLIST_MODE_LOCAL); + if (error != 0) { + log_error("OX: %s", gpgme_strerror(error)); + } + + gpgme_data_t plain = NULL; + gpgme_data_t cipher = NULL; + + gsize s; + guchar* encrypted = g_base64_decode(base64, &s); + error = gpgme_data_new_from_mem(&cipher, (char*)encrypted, s, 0); + if (error != 0) { + log_error("OX: gpgme_data_new_from_mem: %s", gpgme_strerror(error)); + return NULL; + } + + error = gpgme_data_new(&plain); + if (error != 0) { + log_error("OX: %s", gpgme_strerror(error)); + return NULL; + } + + error = gpgme_op_decrypt_verify(ctx, cipher, plain); + if (error != 0) { + log_error("OX: gpgme_op_decrypt: %s", gpgme_strerror(error)); + error = gpgme_op_decrypt(ctx, cipher, plain); + if (error != 0) { + return NULL; + } + } + + size_t len; + char* plain_str = gpgme_data_release_and_get_mem(plain, &len); + char* result = malloc(len + 1); + memcpy(result, plain_str, len); + result[len] = '\0'; + gpgme_free(plain_str); + return result; +} + +/*! + * \brief Read public key from file. + * + * This function is used the read a public key from a file. + * + * This function is used to read a key and push it on PEP. There are some checks + * in this function: + * + * Key is not + * - gkey->revoked + * - gkey->expired + * - gkey->disabled + * - gkey->invalid + * - gkey->secret + * + * Only one key in the file. + * + * \param filename filename to read the file. + * \param key result with base64 encode key or NULL + * \param fp result with the fingerprint or NULL + * + */ +void +p_ox_gpg_readkey(const char* const filename, char** key, char** fp) +{ + log_info("PX: Read OpenPGP Key from file %s", filename); + + GError* error = NULL; + gchar* data = NULL; + gsize size = -1; + + gboolean success = g_file_get_contents(filename, + &data, + &size, + &error); + if (success) { + setlocale(LC_ALL, ""); + gpgme_check_version(NULL); + gpgme_set_locale(NULL, LC_CTYPE, setlocale(LC_CTYPE, NULL)); + gpgme_ctx_t ctx; + gpgme_error_t error = gpgme_new(&ctx); + + if (GPG_ERR_NO_ERROR != error) { + log_error("OX: Read OpenPGP key from file: gpgme_new failed: %s", gpgme_strerror(error)); + return; + } + + error = gpgme_set_protocol(ctx, GPGME_PROTOCOL_OPENPGP); + if (error != GPG_ERR_NO_ERROR) { + log_error("OX: Read OpenPGP key from file: set GPGME_PROTOCOL_OPENPGP: %s", gpgme_strerror(error)); + return; + } + + gpgme_set_armor(ctx, 0); + gpgme_set_textmode(ctx, 0); + gpgme_set_offline(ctx, 1); + gpgme_set_keylist_mode(ctx, GPGME_KEYLIST_MODE_LOCAL); + + gpgme_data_t gpgme_data = NULL; + error = gpgme_data_new(&gpgme_data); + if (error != GPG_ERR_NO_ERROR) { + log_error("OX: Read OpenPGP key from file: gpgme_data_new %s", gpgme_strerror(error)); + return; + } + + error = gpgme_data_new_from_mem(&gpgme_data, (char*)data, size, 0); + if (error != GPG_ERR_NO_ERROR) { + log_error("OX: Read OpenPGP key from file: gpgme_data_new_from_mem %s", gpgme_strerror(error)); + return; + } + error = gpgme_op_keylist_from_data_start(ctx, gpgme_data, 0); + if (error != GPG_ERR_NO_ERROR) { + log_error("OX: Read OpenPGP key from file: gpgme_op_keylist_from_data_start %s", gpgme_strerror(error)); + return; + } + gpgme_key_t gkey; + error = gpgme_op_keylist_next(ctx, &gkey); + if (error != GPG_ERR_NO_ERROR) { + log_error("OX: Read OpenPGP key from file: gpgme_op_keylist_next %s", gpgme_strerror(error)); + return; + } + + gpgme_key_t end; + error = gpgme_op_keylist_next(ctx, &end); + if (error == GPG_ERR_NO_ERROR) { + log_error("OX: Read OpenPGP key from file: ambiguous key"); + return; + } + + if (gkey->revoked || gkey->expired || gkey->disabled || gkey->invalid || gkey->secret) { + log_error("OX: Read OpenPGP key from file: Key is not valid"); + return; + } + + gchar* keybase64 = g_base64_encode((const guchar*)data, size); + + *key = strdup(keybase64); + *fp = strdup(gkey->fpr); + } else { + log_error("OX: Read OpenPGP key from file: Unable to read file: %s", error->message); + } +} + +gboolean +p_ox_gpg_import(char* base64_public_key) +{ + gsize size = -1; + guchar* key = g_base64_decode(base64_public_key, &size); + + setlocale(LC_ALL, ""); + gpgme_check_version(NULL); + gpgme_set_locale(NULL, LC_CTYPE, setlocale(LC_CTYPE, NULL)); + gpgme_ctx_t ctx; + gpgme_error_t error = gpgme_new(&ctx); + + if (GPG_ERR_NO_ERROR != error) { + log_error("OX: Read OpenPGP key from file: gpgme_new failed: %s", gpgme_strerror(error)); + return FALSE; + } + + error = gpgme_set_protocol(ctx, GPGME_PROTOCOL_OPENPGP); + if (error != GPG_ERR_NO_ERROR) { + log_error("OX: Read OpenPGP key from file: set GPGME_PROTOCOL_OPENPGP: %s", gpgme_strerror(error)); + return FALSE; + } + + gpgme_set_armor(ctx, 0); + gpgme_set_textmode(ctx, 0); + gpgme_set_offline(ctx, 1); + gpgme_set_keylist_mode(ctx, GPGME_KEYLIST_MODE_LOCAL); + + gpgme_data_t gpgme_data = NULL; + error = gpgme_data_new(&gpgme_data); + if (error != GPG_ERR_NO_ERROR) { + log_error("OX: Read OpenPGP key from file: gpgme_data_new %s", gpgme_strerror(error)); + return FALSE; + } + + gpgme_data_new_from_mem(&gpgme_data, (gchar*)key, size, 0); + error = gpgme_op_import(ctx, gpgme_data); + if (error != GPG_ERR_NO_ERROR) { + log_error("OX: Failed to import key"); + } + + return TRUE; +} |