merge: sync upstream profanity-im/profanity

Sync with upstream profanity-im/profanity.

Major upstream changes incorporated:

Memory management
  - Replace malloc+memset with g_new0 throughout codebase
  - Adopt auto_gchar / auto_gcharv / auto_gerror / auto_jid cleanup macros
  - Replace free() with g_free() for GAlloc'd memory

Editor rewrite
  - Remove pthread-based async editor; use GChildWatch callback API
  - New launch_editor(initial_content, callback, user_data) interface
  - Proper signal handling (SIGINT, SIGTSTP, SIGPIPE reset in child)
  - ui_suspend()/ui_resume() integration for TTY management

OMEMO improvements
  - Dual backend support: libsignal-protocol-c and libomemo-c
  - Proper pre-key removal after use (XEP-0384 compliance)
  - Automatic pre-key regeneration when store drops below threshold
  - New functions: omemo_is_device_active(), omemo_is_jid_trusted()
  - omemo_get_jid_untrusted_fingerprints() for better error messages
  - Fingerprint notifications on new device identity discovery
  - Deterministic pre-key ID generation tracking max_pre_key_id
  - omemo_trust_changed() UI updates on trust state changes

JID validation
  - RFC 6122-compliant validation in jid_is_valid()
  - Character-level checks (RFC 6122 forbidden chars: & ' / : < > @)
  - Length limits: 1023 per component, 3071 total
  - New jid_is_valid_user_jid() for user vs. service JID distinction

Database
  - Schema migration v3: UNIQUE constraint on archive_id for deduplication
  - Triggers for corrected message tracking (replaces_db_id / replaced_by_db_id)
  - db_history_result_t return type, _truncate_datetime_suffix()

UI / console
  - win_warn_needed() / win_warn_sent() warning deduplication hash table
  - PAD_MIN_HEIGHT dynamic pad sizing with PAD_THRESHOLD auto-cleanup
  - Spellcheck integration in input field with Unicode word detection
  - cons_spellcheck_setting() for /settings ui output
  - /[command]? shortcut for command help

Account config
  - Account name sanitization for GKeyFile special chars ([ ] = # \n \r)
  - Replace popen() with g_spawn_sync() for eval_password
  - TLS policy: add "direct" option alongside legacy

Connection
  - Port validation with g_assert (0–65535)
  - SHA-256 certificate fingerprint support (XMPP_CERT_PUBKEY_FINGERPRINT_SHA256)
  - "direct" TLS policy alias for legacy SSL

Common utilities
  - str_xml_sanitize() for XML 1.0 illegal character removal
  - string_matches_one_of() with formatted error messages
  - valid_tls_policy_option() helper
  - prof_date_time_format_iso8601() utility
  - Improved strip_arg_quotes() with backslash unescaping
  - prof_occurrences() uses g_slist_prepend + reverse for performance

PGP / OX
  - Proper GPGME resource cleanup with goto-cleanup pattern
  - g_string_free(xmppuri) leak fix in _ox_key_lookup

CSV export
  - Use GString + g_file_set_contents instead of raw write() syscalls

Tests
  - Restructured into subdirectories: command/, config/, xmpp/, ui/, omemo/, otr/, pgp/
  - New test_cmd_ac.c for autocompleter unit tests
  - Updated stubs for new UI suspend/resume functions

License headers
  - Migrate to SPDX-3.0 identifiers (GPL-3.0-or-later WITH OpenSSL-exception)

────────────────────────────────────────────────────
cproof-specific preservations:

  - XEP-0308 LMC: replace_id ?: id logic in message/stanza/omemo
  - Force encryption: cmd_force_encryption, test_forced_encryption
  - CWE-134: format string protection (cons_show("%s", ...))
  - y_start_pos-based paging in window.c
  - db_history_result_t return type, _truncate_datetime_suffix()

Merge-time fixes:

  - common.c: format-security (-Werror) — cons_show(errmsg) → cons_show("%s", errmsg)
  - database.c: null-deref guard — !msg->timestamp → msg && !msg->timestamp
  - console.c: implicit size_t → int cast — (int)(maxlen + 1)
  - tlscerts.c: %d for size_t — %zu

Build system:
  - Kept autotools (Makefile.am, configure.ac); upstream uses Meson
  - Restored deleted files: bootstrap.sh, autogen.sh, ax_valgrind_check.m4, configure-debug
  - Updated Makefile.am test paths for subdirectory structure
  - Added test_cmd_ac, test_forced_encryption to test sources

Functional tests:
  - Use cproof version; upstream requires stbbr_for_xmlns from updated stabber
  - Not yet available in devs/stabber fork

Closes #64

Merge author: jabber.developer2
Commits authors:
 Michael Vetter <jubalh@iodoru.org>
& Steffen Jaeckel <s@jaeckel.eu>

src/xmpp/omemo.c

@@ -4,33 +4,7 @@
  *
  * Copyright (C) 2019 Paul Fariello <paul@fariello.eu>
  *
- * 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.
- *
+ * SPDX-License-Identifier: GPL-3.0-or-later WITH OpenSSL-exception
  */
 
 #include "config.h"
@@ -116,6 +90,11 @@ omemo_devicelist_request(const char* const jid)
 void
 omemo_bundle_publish(gboolean first)
 {
+    if (!connection_supports(XMPP_FEATURE_PUBSUB_PUBLISH_OPTIONS)) {
+        cons_show("OMEMO: Cannot publish bundle: no PUBSUB feature announced");
+        log_debug("[OMEMO] Cannot publish bundle: no PUBSUB feature announced");
+        return;
+    }
     log_debug("[OMEMO] publish own OMEMO bundle");
     xmpp_ctx_t* const ctx = connection_get_ctx();
     unsigned char* identity_key = NULL;
@@ -141,14 +120,10 @@ omemo_bundle_publish(gboolean first)
     g_list_free(lengths);
     g_list_free(ids);
 
-    if (connection_supports(XMPP_FEATURE_PUBSUB_PUBLISH_OPTIONS)) {
-        stanza_attach_publish_options_va(ctx, iq,
-                                         4, // 2 * number of key-value pairs
-                                         "pubsub#persist_items", "true",
-                                         "pubsub#access_model", "open");
-    } else {
-        log_debug("[OMEMO] Cannot publish bundle: no PUBSUB feature announced");
-    }
+    stanza_attach_publish_options_va(ctx, iq,
+                                     4, // 2 * number of key-value pairs
+                                     "pubsub#persist_items", "true",
+                                     "pubsub#access_model", "open");
 
     iq_id_handler_add(id, _omemo_bundle_publish_result, NULL, GINT_TO_POINTER(first));
 
@@ -219,7 +194,7 @@ omemo_start_device_session_handle_bundle(xmpp_stanza_t* const stanza, void* cons
         goto out;
     }
 
-    uint32_t device_id = strtoul(++device_id_str, NULL, 10);
+    uint32_t device_id = (uint32_t)strtoul(++device_id_str, NULL, 10);
     log_debug("[OMEMO] omemo_start_device_session_handle_bundle: %d", device_id);
 
     xmpp_stanza_t* item = xmpp_stanza_get_child_by_name(items, "item");
@@ -243,7 +218,7 @@ omemo_start_device_session_handle_bundle(xmpp_stanza_t* const stanza, void* cons
             continue;
         }
 
-        omemo_key_t* key = malloc(sizeof(omemo_key_t));
+        omemo_key_t* key = g_new0(omemo_key_t, 1);
         key->data = NULL;
 
         const char* prekey_id_text = xmpp_stanza_get_attribute(prekey, "preKeyId");
@@ -252,7 +227,7 @@ omemo_start_device_session_handle_bundle(xmpp_stanza_t* const stanza, void* cons
             continue;
         }
 
-        key->id = strtoul(prekey_id_text, NULL, 10);
+        key->id = (uint32_t)strtoul(prekey_id_text, NULL, 10);
         xmpp_stanza_t* prekey_text = xmpp_stanza_get_children(prekey);
 
         if (!prekey_text) {
@@ -282,7 +257,7 @@ omemo_start_device_session_handle_bundle(xmpp_stanza_t* const stanza, void* cons
         goto out;
     }
 
-    uint32_t signed_prekey_id = strtoul(signed_prekey_id_text, NULL, 10);
+    uint32_t signed_prekey_id = (uint32_t)strtoul(signed_prekey_id_text, NULL, 10);
     xmpp_stanza_t* signed_prekey_text = xmpp_stanza_get_children(signed_prekey);
     if (!signed_prekey_text) {
         goto out;
@@ -349,8 +324,12 @@ out:
 }
 
 char*
-omemo_receive_message(xmpp_stanza_t* const stanza, gboolean* trusted)
+omemo_receive_message(xmpp_stanza_t* const stanza, gboolean* trusted, omemo_error_t* error)
 {
+    if (!stanza || !trusted || !error) {
+        return NULL;
+    }
+
     char* plaintext = NULL;
     const char* type = xmpp_stanza_get_type(stanza);
     const char* from = xmpp_stanza_get_from(stanza);
@@ -359,6 +338,9 @@ omemo_receive_message(xmpp_stanza_t* const stanza, gboolean* trusted)
     unsigned char* payload_raw = NULL;
     char* iv_text = NULL;
     char* payload_text = NULL;
+    size_t payload_len = 0;
+
+    *error = OMEMO_ERR_NONE;
 
     xmpp_stanza_t* encrypted = xmpp_stanza_get_child_by_ns(stanza, STANZA_NS_OMEMO);
     if (!encrypted) {
@@ -367,41 +349,44 @@ omemo_receive_message(xmpp_stanza_t* const stanza, gboolean* trusted)
 
     xmpp_stanza_t* header = xmpp_stanza_get_child_by_name(encrypted, "header");
     if (!header) {
+        *error = OMEMO_ERR_OTHER;
         return NULL;
     }
 
     const char* sid_text = xmpp_stanza_get_attribute(header, "sid");
     if (!sid_text) {
+        *error = OMEMO_ERR_OTHER;
         return NULL;
     }
-    uint32_t sid = strtoul(sid_text, NULL, 10);
+    uint32_t sid = (uint32_t)strtoul(sid_text, NULL, 10);
 
     xmpp_stanza_t* iv = xmpp_stanza_get_child_by_name(header, "iv");
     if (!iv) {
+        *error = OMEMO_ERR_OTHER;
         return NULL;
     }
     iv_text = xmpp_stanza_get_text(iv);
     if (!iv_text) {
+        *error = OMEMO_ERR_OTHER;
         return NULL;
     }
     size_t iv_len;
     iv_raw = g_base64_decode(iv_text, &iv_len);
     if (!iv_raw) {
+        *error = OMEMO_ERR_OTHER;
         return NULL;
     }
 
     xmpp_stanza_t* payload = xmpp_stanza_get_child_by_name(encrypted, "payload");
-    if (!payload) {
-        goto quit;
-    }
-    payload_text = xmpp_stanza_get_text(payload);
-    if (!payload_text) {
-        goto quit;
-    }
-    size_t payload_len;
-    payload_raw = g_base64_decode(payload_text, &payload_len);
-    if (!payload_raw) {
-        goto quit;
+    if (payload) {
+        payload_text = xmpp_stanza_get_text(payload);
+        if (payload_text) {
+            payload_raw = g_base64_decode(payload_text, &payload_len);
+            if (!payload_raw) {
+                *error = OMEMO_ERR_OTHER;
+                goto quit;
+            }
+        }
     }
 
     xmpp_stanza_t* key_stanza;
@@ -410,7 +395,7 @@ omemo_receive_message(xmpp_stanza_t* const stanza, gboolean* trusted)
             continue;
         }
 
-        omemo_key_t* key = malloc(sizeof(omemo_key_t));
+        omemo_key_t* key = g_new0(omemo_key_t, 1);
         char* key_text = xmpp_stanza_get_text(key_stanza);
         if (!key_text) {
             free(key);
@@ -418,7 +403,7 @@ omemo_receive_message(xmpp_stanza_t* const stanza, gboolean* trusted)
         }
 
         const char* rid_text = xmpp_stanza_get_attribute(key_stanza, "rid");
-        key->device_id = strtoul(rid_text, NULL, 10);
+        key->device_id = (uint32_t)strtoul(rid_text, NULL, 10);
         if (!key->device_id) {
             free(key);
             continue;
@@ -437,7 +422,7 @@ omemo_receive_message(xmpp_stanza_t* const stanza, gboolean* trusted)
 
     plaintext = omemo_on_message_recv(from, sid, iv_raw, iv_len,
                                       keys, payload_raw, payload_len,
-                                      g_strcmp0(type, STANZA_TYPE_GROUPCHAT) == 0, trusted);
+                                      g_strcmp0(type, STANZA_TYPE_GROUPCHAT) == 0, trusted, error);
 
     if (keys) {
         g_list_free_full(keys, (GDestroyNotify)omemo_key_free);
@@ -722,3 +707,24 @@ _omemo_bundle_publish_configure_result(xmpp_stanza_t* const stanza, void* const
 
     return 0;
 }
+
+gchar*
+omemo_error_to_string(omemo_error_t error)
+{
+    switch (error) {
+    case OMEMO_ERR_NO_KEY:
+        return g_strdup("OMEMO message received but no key for this device found.");
+    case OMEMO_ERR_NOT_TRUSTED:
+        return g_strdup("OMEMO message received but sender identity is untrusted.");
+    case OMEMO_ERR_NO_SESSION:
+        return g_strdup("OMEMO message received but no session found. Try '/omemo start'.");
+    case OMEMO_ERR_DECRYPT_FAILED:
+        return g_strdup("OMEMO message received but decryption failed.");
+    case OMEMO_ERR_KEY_TRANSPORT:
+        return NULL;
+    case OMEMO_ERR_NONE:
+        return NULL;
+    default:
+        return g_strdup("OMEMO message received but could not be decrypted.");
+    }
+}