From 10d8447d301d880bd2dd9ad8d76560039aff5b03 Mon Sep 17 00:00:00 2001
From: Johannes Findeisen <you@hanez.org>
Date: Sat, 17 Aug 2024 22:00:58 +0200
Subject: [PATCH] Added MAX_UID.

---
 README.md |  2 +-
 checkpw.c | 10 +++++++---
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/README.md b/README.md
index 49d5edf..b0cbede 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-# checkpw - 1.0!
+# checkpw - 1.0.1!
 
 checkpw is a program that checks the validity of a users password on a Linux/PAM-based system.
 
diff --git a/checkpw.c b/checkpw.c
index 793d989..29b0206 100644
--- a/checkpw.c
+++ b/checkpw.c
@@ -29,6 +29,10 @@
 #define MAX_USERNAME_LEN 32
 #define MAX_PASSWORD_LEN 256
 
+#ifndef MAX_UID
+#define MAX_UID 1000
+#endif
+
 #ifndef MIN_UID
 #define MIN_UID 1000
 #endif
@@ -238,9 +242,9 @@ int main(int argc, char *argv[]) {
         exit(1);
     }
 
-    // Check if the user's UID is below the minimum allowed UID
-    if (pwd->pw_uid < MIN_UID) {
-        fprintf(stderr, "Error: User '%s' has a UID less than %d and is not allowed to authenticate.\n", username, MIN_UID);
+    // Check if the user's UID is below the minimum allowed UID and not higher than maximum allowed UID
+    if (pwd->pw_uid < MIN_UID || pwd->pw_uid > MAX_UID) {
+        fprintf(stderr, "Error: User '%s' has a UID less than %d or higher than %d and is not allowed to authenticate.\n", username, MIN_UID, MAX_UID);
         exit(1);
     }