[pgmoneta#983]admin: guard strtok() results when parsing users file

Signed-off-by: Amr-Shams <amr.shams2015.as@gmail.com>

Author: Amr-Shams

src/admin.c

@@ -665,6 +665,11 @@ add_user(char* users_path, char* username, char* password, bool generate_pwd, in
    while (fgets(line, sizeof(line), users_file))
    {
       ptr = strtok(line, ":");
+      if (ptr == NULL)
+      {
+         warnx("invalid users file line while adding user");
+         goto error;
+      }
       if (!strcmp(username, ptr))
       {
          warnx("Existing user: %s", username);
@@ -994,6 +999,11 @@ update_user(char* users_path, char* username, char* password, bool generate_pwd,
       memcpy(&line_copy, &line, strlen(line));
 
       ptr = strtok(line, ":");
+      if (ptr == NULL)
+      {
+         warnx("invalid users file line while updating user");
+         goto error;
+      }
       if (!strcmp(username, ptr))
       {
          /* Password */
@@ -1317,6 +1327,11 @@ remove_user(char* users_path, char* username, int32_t output_format)
       memcpy(&line_copy, &line, strlen(line));
 
       ptr = strtok(line, ":");
+      if (ptr == NULL)
+      {
+         warnx("invalid users file line while removing user");
+         goto error;
+      }
       if (!strcmp(username, ptr))
       {
          found = true;
@@ -1439,6 +1454,11 @@ list_users(char* users_path, int32_t output_format)
    while (fgets(line, sizeof(line), users_file))
    {
       ptr = strtok(line, ":");
+      if (ptr == NULL)
+      {
+         warnx("skipping malformed users file line while listing users");
+         continue;
+      }
       if (strchr(ptr, '\n'))
       {
          continue;
@@ -1573,6 +1593,11 @@ create_response(char* users_path, struct json* json, struct json** response)
    while (fgets(line, sizeof(line), users_file))
    {
       ptr = strtok(line, ":");
+      if (ptr == NULL)
+      {
+         warnx("skipping malformed users file line while creating response");
+         continue;
+      }
       if (strchr(ptr, '\n'))
       {
          continue;
@@ -1591,4 +1616,4 @@ create_response(char* users_path, struct json* json, struct json** response)
    pgmoneta_json_destroy(r);
 
    return 1;
-}
+}