refactor: filter inbound strings according to type

Names have different requirements than non-names, so we
now filter them differently. Also added the colon character
to the invalid nick char list because the colon is used for
extracting nicks from logs.

src/chat.c

@@ -1578,7 +1578,7 @@ static void chat_onDraw(ToxWindow *self, Toxic *toxic)
         tox_friend_get_status_message(toxic->tox, self->num, (uint8_t *) statusmsg, NULL);
         const size_t s_len = tox_friend_get_status_message_size(toxic->tox, self->num, NULL);
 
-        filter_str(statusmsg, s_len);
+        filter_string(statusmsg, s_len, false);
         snprintf(statusbar->statusmsg, sizeof(statusbar->statusmsg), "%s", statusmsg);
         statusbar->statusmsg_len = strlen(statusbar->statusmsg);
 
@@ -1738,7 +1738,7 @@ static void chat_onInit(ToxWindow *self, Toxic *toxic)
         char statusmsg[TOX_MAX_STATUS_MESSAGE_LENGTH + 1] = {0};
         tox_friend_get_status_message(tox, self->num, (uint8_t *) statusmsg, NULL);
         statusmsg[s_len] = '\0';
-        filter_str(statusmsg, s_len);
+        filter_string(statusmsg, s_len, false);
         snprintf(statusbar->statusmsg, sizeof(statusbar->statusmsg), "%s", statusmsg);
     }
 

src/friendlist.c

@@ -1301,7 +1301,7 @@ static void friendlist_onDraw(ToxWindow *self, Toxic *toxic)
 
                     statusmsg[s_len] = '\0';
 
-                    filter_str(statusmsg, s_len);
+                    filter_string(statusmsg, s_len, false);
 
                     pthread_mutex_lock(&Winthread.lock);
                     snprintf(Friends.list[f].statusmsg, sizeof(Friends.list[f].statusmsg), "%s", statusmsg);
@@ -1796,7 +1796,7 @@ bool friend_config_set_alias(const char *public_key, const char *alias, uint16_t
 
     char tmp[TOXIC_MAX_NAME_LENGTH + 1];
     const uint16_t tmp_len = copy_tox_str(tmp, sizeof(tmp), alias, length);
-    filter_str(tmp, tmp_len);
+    filter_string(tmp, tmp_len, true);
 
     if (tmp_len == 0 || tmp_len > TOXIC_MAX_NAME_LENGTH) {
         return false;

src/groupchats.c

@@ -451,7 +451,7 @@ void groupchat_update_statusbar_topic(ToxWindow *self, const Tox *tox)
 
     tox_group_get_topic(tox, self->num, (uint8_t *)topic, NULL);
     topic[t_len] = '\0';
-    filter_str(topic, t_len);
+    filter_string(topic, t_len, false);
     snprintf(statusbar->topic, sizeof(statusbar->topic), "%s", topic);
     statusbar->topic_len = strlen(statusbar->topic);
 }

src/misc_tools.c

@@ -305,59 +305,53 @@ int qsort_ptr_char_array_helper(const void *str1, const void *str2)
     return strcasecmp(*(const char *const *)str1, *(const char *const *)str2);
 }
 
-static const char invalid_chars[] = {'/', '\n', '\t', '\v', '\r', '\0'};
+/* List of characters we don't allow in nicks. */
+static const char invalid_nick_chars[] = {':', '/', '\0', '\a', '\b', '\f', '\n', '\r', '\t', '\v'};
+
+/* List of characters we don't allow in single-line strings. */
+static const char invalid_string_chars[] = {'\0', '\a', '\b', '\f', '\n', '\r', '\t', '\v'};
 
 /*
- * Helper function for `valid_nick()`.
- *
- * Returns true if `ch` is not in the `invalid_chars` array.
+ * Returns true if the character `ch` is not in the supplied `invalid_chars` array.
  */
-static bool is_valid_char(char ch)
+static bool is_valid_char(char ch, const char *const invalid_chars, size_t list_length)
 {
-    char tmp;
-
-    for (size_t i = 0; (tmp = invalid_chars[i]); ++i) {
-        if (tmp == ch) {
+    for (size_t i = 0; i < list_length; ++i) {
+        if (invalid_chars[i] == ch) {
             return false;
         }
     }
 
     return true;
 }
 
-/* Returns true if nick is valid.
- *
- * A valid toxic nick:
- * - cannot be empty
- * - cannot start with a space
- * - must not contain a forward slash (for logfile naming purposes)
- * - must not contain contiguous spaces
- * - must not contain a newline or tab seqeunce
- */
 bool valid_nick(const char *nick)
 {
     if (!nick[0] || nick[0] == ' ') {
         return false;
     }
 
-    for (size_t i = 0; nick[i]; ++i) {
+    for (size_t i = 0; nick[i] != '\0'; ++i) {
         char ch = nick[i];
 
-        if ((ch == ' ' && nick[i + 1] == ' ') || !is_valid_char(ch)) {
+        if ((ch == ' ' && nick[i + 1] == ' ')
+                || !is_valid_char(ch, invalid_nick_chars, sizeof(invalid_nick_chars))) {
             return false;
         }
     }
 
     return true;
 }
 
-/* Converts all newline/tab chars to spaces (use for strings that should be contained to a single line) */
-void filter_str(char *str, size_t len)
+void filter_string(char *str, size_t len, bool is_nick)
 {
+    const char *const invalid_chars = is_nick ? invalid_nick_chars : invalid_string_chars;
+    const size_t list_length = is_nick ? sizeof(invalid_nick_chars) : sizeof(invalid_string_chars);
+
     for (size_t i = 0; i < len; ++i) {
         char ch = str[i];
 
-        if (!is_valid_char(ch) || str[i] == '\0') {
+        if (!is_valid_char(ch, invalid_chars, list_length)) {
             str[i] = ' ';
         }
     }
@@ -450,7 +444,7 @@ size_t get_nick_truncate(Tox *tox, char *buf, uint16_t buf_size, uint32_t friend
 
     len = MIN(len, buf_size - 1);
     buf[len] = '\0';
-    filter_str(buf, len);
+    filter_string(buf, len, false);
 
     return len;
 
@@ -475,7 +469,7 @@ int get_conference_nick_truncate(Tox *tox, char *buf, uint32_t peernum, uint32_t
 
     len = MIN(len, TOXIC_MAX_NAME_LENGTH - 1);
     buf[len] = '\0';
-    filter_str(buf, len);
+    filter_string(buf, len, true);
     return len;
 
 on_error:
@@ -507,7 +501,7 @@ size_t get_group_nick_truncate(Tox *tox, char *buf, uint32_t peer_id, uint32_t g
     len = MIN(len, TOXIC_MAX_NAME_LENGTH - 1);
     buf[len] = '\0';
 
-    filter_str(buf, len);
+    filter_string(buf, len, true);
 
     return len;
 }
@@ -531,9 +525,9 @@ size_t get_group_self_nick_truncate(Tox *tox, char *buf, uint32_t groupnum)
     }
 
     len = MIN(len, TOXIC_MAX_NAME_LENGTH - 1);
-    buf[len] = 0;
+    buf[len] = '\0';
 
-    filter_str(buf, len);
+    filter_string(buf, len, true);
 
     return len;
 }

src/misc_tools.h

@@ -162,16 +162,22 @@ int qsort_ptr_char_array_helper(const void *str1, const void *str2);
  * A valid toxic nick:
  * - cannot be empty
  * - cannot start with a space
- * - must not contain a forward slash (for logfile naming purposes)
- * - must not contain contiguous spaces
- * - must not contain a newline or tab seqeunce
+ * - cannot contain contiguous spaces
+ * - cannot contain forward slash (for log file naming purposes)
+ * - cannot contain any characters in the `invalid_nick_chars` array that
+ *   resides in misc_tools.c.
  */
 bool valid_nick(const char *nick);
 
-/* Converts all newline/tab chars to spaces
- * (use for strings that should be contained to a single line)
+/* Converts all invalid single-line string characters to spaces (newlines,
+ * tabs, nul etc.).
+ *
+ * If `is_nick` is true, additional characters specific to nicks are filtered.
+ *
+ * This function is used for strings that should be human-readable, and contained
+ * to a single line, such as status messages, nicks, and group topics.
  */
-void filter_str(char *str, size_t len);
+void filter_string(char *str, size_t len, bool is_nick);
 
 /* gets base file name from path or original file name if no path is supplied */
 size_t get_file_name(char *namebuf, size_t bufsize, const char *pathname);

src/windows.c

@@ -54,6 +54,7 @@ void on_friend_request(Tox *tox, const uint8_t *public_key, const uint8_t *data,
 
     char msg[MAX_STR_SIZE + 1];
     length = copy_tox_str(msg, sizeof(msg), (const char *) data, length);
+    filter_string(msg, length, false);
 
     for (uint16_t i = 0; i < windows->count; ++i) {
         ToxWindow *w = windows->list[i];
@@ -136,7 +137,7 @@ void on_friend_name(Tox *tox, uint32_t friendnumber, const uint8_t *string, size
 
     char nick[TOXIC_MAX_NAME_LENGTH + 1];
     length = copy_tox_str(nick, sizeof(nick), (const char *) string, length);
-    filter_str(nick, length);
+    filter_string(nick, length, true);
 
     for (uint16_t i = 0; i < windows->count; ++i) {
         ToxWindow *w = windows->list[i];
@@ -159,7 +160,7 @@ void on_friend_status_message(Tox *tox, uint32_t friendnumber, const uint8_t *st
 
     char msg[TOX_MAX_STATUS_MESSAGE_LENGTH + 1];
     length = copy_tox_str(msg, sizeof(msg), (const char *) string, length);
-    filter_str(msg, length);
+    filter_string(msg, length, false);
 
     for (uint16_t i = 0; i < windows->count; ++i) {
         ToxWindow *w = windows->list[i];
@@ -266,7 +267,7 @@ void on_conference_peer_name(Tox *tox, uint32_t conferencenumber, uint32_t peern
 
     char nick[TOXIC_MAX_NAME_LENGTH + 1];
     length = copy_tox_str(nick, sizeof(nick), (const char *) name, length);
-    filter_str(nick, length);
+    filter_string(nick, length, true);
 
     for (uint16_t i = 0; i < windows->count; ++i) {
         ToxWindow *w = windows->list[i];
@@ -286,6 +287,7 @@ void on_conference_title(Tox *tox, uint32_t conferencenumber, uint32_t peernumbe
 
     char data[MAX_STR_SIZE + 1];
     length = copy_tox_str(data, sizeof(data), (const char *) title, length);
+    filter_string(data, length, false);
 
     for (uint16_t i = 0; i < windows->count; ++i) {
         ToxWindow *w = windows->list[i];
@@ -570,12 +572,14 @@ void on_group_peer_exit(Tox *tox, uint32_t groupnumber, uint32_t peer_id, Tox_Gr
 
     char toxic_nick[TOXIC_MAX_NAME_LENGTH + 1];
     nick_len = copy_tox_str(toxic_nick, sizeof(toxic_nick), (const char *) nick, nick_len);
+    filter_string(toxic_nick, nick_len, true);
 
     char buf[MAX_STR_SIZE + 1] = {0};
     size_t buf_len = 0;
 
     if (part_message) {
         buf_len = copy_tox_str(buf, sizeof(buf), (const char *) part_message, length);
+        filter_string(buf, buf_len, false);
     }
 
     for (uint16_t i = 0; i < windows->count; ++i) {
@@ -597,6 +601,7 @@ void on_group_topic_change(Tox *tox, uint32_t groupnumber, uint32_t peer_id, con
 
     char data[MAX_STR_SIZE + 1];
     length = copy_tox_str(data, sizeof(data), (const char *) topic, length);
+    filter_string(data, length, false);
 
     for (uint16_t i = 0; i < windows->count; ++i) {
         ToxWindow *w = windows->list[i];
@@ -681,7 +686,7 @@ void on_group_nick_change(Tox *tox, uint32_t groupnumber, uint32_t peer_id, cons
 
     char name[TOXIC_MAX_NAME_LENGTH + 1];
     length = copy_tox_str(name, sizeof(name), (const char *) newname, length);
-    filter_str(name, length);
+    filter_string(name, length, true);
 
     for (uint16_t i = 0; i < windows->count; ++i) {
         ToxWindow *w = windows->list[i];