misc-progs: Add functions to sanitise input arguments

[ipfire-2.x.git] / src / misc-progs / setuid.c

diff --git a/src/misc-progs/setuid.c b/src/misc-progs/setuid.c
index 6637d3e6fcba82bc40acd27a62160d57e2c0544e..efd181ad8c51beb0e709dc4da0a5ac3a0a482436 100644 (file)
--- a/src/misc-progs/setuid.c
+++ b/src/misc-progs/setuid.c
@@ -199,3 +199,42 @@ int initsetuid(void) {
 
        return 1;
 }
+
+/* Checks if a string only contains alphanumerical characters, dash or underscore */
+int is_valid_argument_alnum(const char* arg) {
+       size_t l = strlen(arg);
+
+       for (unsigned int i = 0; i < l; i++) {
+               char c = arg[i];
+
+               // Dash or underscore
+               if (c == '-' || c == '_')
+                       continue;
+
+               // Any alphanumerical character
+               if (isalnum(c))
+                       continue;
+
+               // Invalid
+               return 0;
+       }
+
+       return 1;
+}
+
+int is_valid_argument_num(const char* arg) {
+       size_t l = strlen(arg);
+
+       for (unsigned int i = 0; i < l; i++) {
+               char c = arg[i];
+
+               // Any digit
+               if (isdigit(c))
+                       continue;
+
+               // Invalid
+               return 0;
+       }
+
+       return 1;
+}