Use /omemo fingerprint to show contact fingerprints

Don't print fingerprints when they are received

src/command/cmd_ac.c

@@ -2153,6 +2153,11 @@ _omemo_autocomplete(ProfWin *window, const char *const input, gboolean previous)
         }
     }
 
+    found = autocomplete_param_with_func(input, "/omemo fingerprint", roster_contact_autocomplete, previous);
+    if (found) {
+        return found;
+    }
+
     found = autocomplete_param_with_ac(input, "/omemo log", omemo_log_ac, TRUE, previous);
     if (found) {
         return found;

src/command/cmd_defs.c

@@ -2350,7 +2350,7 @@ static struct cmd_t command_defs[] =
             "/omemo start [<contact>]",
             "/omemo trust [<contact>] <fingerprint>",
             "/omemo end",
-            "/omemo fingerprint")
+            "/omemo fingerprint [<contact>]")
         CMD_DESC(
             "Omemo commands to manage keys, and perform encryption during chat sessions.")
         CMD_ARGS(
@@ -2359,7 +2359,7 @@ static struct cmd_t command_defs[] =
             { "end",               "End the current OMEMO session," },
             { "log on|off",        "Enable or disable plaintext logging of OMEMO encrypted messages." },
             { "log redact",        "Log OMEMO encrypted messages, but replace the contents with [redacted]. This is the default." },
-            { "fingerprint",       "Show current device fingerprint." })
+            { "fingerprint",       "Show contact fingerprints." })
         CMD_EXAMPLES(
             "/omemo gen",
             "/omemo start buddy@buddychat.org",

src/command/cmd_funcs.c

@@ -8080,9 +8080,49 @@ cmd_omemo_fingerprint(ProfWin *window, const char *const command, gchar **args)
         return TRUE;
     }
 
-    char *fingerprint = omemo_own_fingerprint(TRUE);
-    cons_show("%s", fingerprint);
-    free(fingerprint);
+    Jid *jid;
+    if (!args[1]) {
+        if (window->type == WIN_CONSOLE) {
+            char *fingerprint = omemo_own_fingerprint(TRUE);
+            cons_show("Your OMEMO fingerprint: %s", fingerprint);
+            free(fingerprint);
+            return TRUE;
+        } else if (window->type == WIN_CHAT) {
+            ProfChatWin *chatwin = (ProfChatWin*)window;
+            jid = jid_create(chatwin->barejid);
+        } else {
+            win_println(window, THEME_DEFAULT, '-', "You must be in a regular chat window to print fingerprint without providing the contact.");
+            return TRUE;
+        }
+    } else {
+        jid = jid_create(args[1]);
+        if (!jid) {
+            cons_show("%s is not a valid jid", args[1]);
+            return TRUE;
+        }
+    }
+
+    GList *fingerprints = omemo_known_device_identities(jid->barejid);
+    GList *fingerprint;
+
+    if (!fingerprints) {
+        win_println(window, THEME_DEFAULT, '-', "There is no known fingerprints for %s", jid->barejid);
+        return TRUE;
+    }
+
+    for (fingerprint = fingerprints; fingerprint != NULL; fingerprint = fingerprint->next) {
+        char *formatted_fingerprint = omemo_format_fingerprint(fingerprint->data);
+        gboolean trusted = omemo_is_trusted_identity(jid->barejid, fingerprint->data);
+
+        win_println(window, THEME_DEFAULT, '-', "%s's OMEMO fingerprint: %s%s", jid->barejid, formatted_fingerprint, trusted ? " (trusted)" : "");
+
+        free(formatted_fingerprint);
+    }
+
+    g_list_free(fingerprints);
+
+    win_println(window, THEME_DEFAULT, '-', "You can trust it with '/omemo trust <fingerprint>'");
+    win_println(window, THEME_DEFAULT, '-', "You can untrust it with '/omemo untrust <fingerprint>'");
 
     return TRUE;
 #else

src/omemo/omemo.c

@@ -496,32 +496,6 @@ omemo_start_device_session(const char *const jid, uint32_t device_id,
 
     gboolean trusted = is_trusted_identity(&address, (uint8_t *)identity_key_raw, identity_key_len, &omemo_ctx.identity_key_store);
 
-    Jid *ownjid = jid_create(connection_get_fulljid());
-    if (g_strcmp0(jid, ownjid->barejid) == 0) {
-        char *fingerprint = omemo_fingerprint(identity_key, TRUE);
-
-        cons_show("Available device identity for %s: %s%s", ownjid->barejid, fingerprint, trusted ? " (trusted)" : "");
-        if (trusted) {
-            cons_show("You can untrust it with '/omemo untrust %s <fingerprint>'", ownjid->barejid);
-        } else {
-            cons_show("You can trust it with '/omemo trust %s <fingerprint>'", ownjid->barejid);
-        }
-        free(fingerprint);
-    }
-
-    ProfChatWin *chatwin = wins_get_chat(jid);
-    if (chatwin) {
-        char *fingerprint = omemo_fingerprint(identity_key, TRUE);
-
-        win_println((ProfWin *)chatwin, THEME_DEFAULT, '-', "Available device identity: %s%s", fingerprint, trusted ? " (trusted)" : "");
-        if (trusted) {
-            win_println((ProfWin *)chatwin, THEME_DEFAULT, '-', "You can untrust it with '/omemo untrust <fingerprint>'");
-        } else {
-            win_println((ProfWin *)chatwin, THEME_DEFAULT, '-', "You can trust it with '/omemo trust <fingerprint>'");
-        }
-        free(fingerprint);
-    }
-
     if (!trusted) {
         goto out;
     }
@@ -570,7 +544,6 @@ omemo_start_device_session(const char *const jid, uint32_t device_id,
 
 out:
     SIGNAL_UNREF(identity_key);
-    jid_destroy(ownjid);
 }
 
 char *
@@ -884,6 +857,50 @@ omemo_own_fingerprint(gboolean formatted)
     return omemo_fingerprint(identity, formatted);
 }
 
+GList *
+omemo_known_device_identities(const char *const jid)
+{
+    GHashTable *known_identities = g_hash_table_lookup(omemo_ctx.known_devices, jid);
+    if (!known_identities) {
+        return NULL;
+    }
+
+    return g_hash_table_get_keys(known_identities);
+}
+
+gboolean
+omemo_is_trusted_identity(const char *const jid, const char *const fingerprint)
+{
+    GHashTable *known_identities = g_hash_table_lookup(omemo_ctx.known_devices, jid);
+    if (!known_identities) {
+        return FALSE;
+    }
+
+    void *device_id = g_hash_table_lookup(known_identities, fingerprint);
+    if (!device_id) {
+        return FALSE;
+    }
+
+    signal_protocol_address address = {
+        .name = jid,
+        .name_len = strlen(jid),
+        .device_id = GPOINTER_TO_INT(device_id),
+    };
+
+    size_t fingerprint_len;
+    unsigned char *fingerprint_raw = omemo_fingerprint_decode(fingerprint, &fingerprint_len);
+    unsigned char djb_type[] = {'\x05'};
+    signal_buffer *buffer = signal_buffer_create(djb_type, 1);
+    buffer = signal_buffer_append(buffer, fingerprint_raw, fingerprint_len);
+
+    gboolean trusted = is_trusted_identity(&address, signal_buffer_data(buffer), signal_buffer_len(buffer), &omemo_ctx.identity_key_store);
+
+    free(fingerprint_raw);
+    signal_buffer_free(buffer);
+
+    return trusted;
+}
+
 static char *
 omemo_fingerprint(ec_public_key *identity, gboolean formatted)
 {

src/omemo/omemo.h

@@ -36,6 +36,8 @@ char *omemo_format_fingerprint(const char *const fingerprint);
 char *omemo_own_fingerprint(gboolean formatted);
 void omemo_trust(const char *const jid, const char *const fingerprint);
 void omemo_untrust(const char *const jid, const char *const fingerprint);
+GList *omemo_known_device_identities(const char *const jid);
+gboolean omemo_is_trusted_identity(const char *const jid, const char *const fingerprint);
 
 void omemo_start_session(const char *const barejid);
 void omemo_start_muc_sessions(const char *const roomjid);