Tweak scrypt_fuzzer

RustCrypto · Oct 23, 2024 · 930fb04 · 930fb04
1 parent 6ff6fc4
commit 930fb04
Showing 1 changed file with 33 additions and 49 deletions.
diff --git a/fuzz/fuzz_targets/scrypt_fuzzer.rs b/fuzz/fuzz_targets/scrypt_fuzzer.rs
@@ -18,8 +18,8 @@ use libfuzzer_sys::fuzz_target;
 use scrypt::{scrypt, Params, Scrypt};
 use scrypt::password_hash::{Ident, PasswordHash, PasswordHasher, PasswordVerifier, SaltString};
 
-const SAMPLE_HASH: &str =
-    "$scrypt$ln=16,r=8,p=1$aM15713r3Xsvxbi31lqr1Q$nFNh2CVHVjNldFVKDHDlm4CbdRSCdEBsjjJxD+iCs5E";
+const SAMPLE_HASH: &str = "$scrypt$ln=16,r=8,p=1$\
+    aM15713r3Xsvxbi31lqr1Q$nFNh2CVHVjNldFVKDHDlm4CbdRSCdEBsjjJxD+iCs5E";
 
 // Generate random params
 fn fuzzed_params(data: &[u8]) -> Option<Params> {
@@ -89,53 +89,37 @@ fuzz_target!(|data: &[u8]| {
     let splits = split_fuzz_data(data, &[32, 32, 32]);
     let password = splits.first().unwrap_or(&data);
     let salt = splits.get(1).unwrap_or(&data);
-    let mut result = vec![0u8; 256];
-
-    if let Some(salt_string) = fuzzed_salt(salt) {
-        if !validate_salt(salt_string.as_str()) {
-            return;
-        }
-
-        let salt_value = salt_string.as_salt(); // Safe to use now
-
-        let formatted_hash = format!("$scrypt$ln=16,r=8,p=1${}$invalid$", base16ct::lower::encode_string(password));
-
-        if let Ok(hash) =
-            PasswordHash::new(SAMPLE_HASH).or_else(|_| PasswordHash::new(formatted_hash.as_str()))
-        {
-            // Randomly choose the fuzz target function
-            let target_selector = if !data.is_empty() { data[0] % 5 } else { 0 };
-            match target_selector {
-                0 => {
-                    let _ = scrypt(password, salt, &params, &mut result);
-                }
-                1 => {
-                    let _ = Scrypt.verify_password(password, &hash).is_err();
-                }
-                2 => {
-                    let _ = Scrypt.hash_password_customized(
-                        password,
-                        Some(Ident::new_unwrap("scrypt")),
-                        None,
-                        params,
-                        salt_value,
-                    );
-                }
-                3 => {
-                    if let Some(random_params) = fuzzed_params(password) {
-                        let _ = scrypt(password, salt, &random_params, &mut result);
-                    }
-                }
-                4 => {
-                    let _ = PasswordHash::new(SAMPLE_HASH).is_ok();
-                }
-                _ => {
-                    let _ = scrypt(password, salt, &params, &mut result);
-                }
+    let mut result = [0u8; 256];
+
+    let salt_value = match fuzzed_salt(salt) {
+        Some(s) if validate_salt(s) => s.as_salt(),
+        _ => return,
+    };
+
+    let hash = PasswordHash::new(SAMPLE_HASH).expect("SAMPLE_HASH is valid");
+
+    // Randomly choose the fuzz target function
+    let target_selector = if !data.is_empty() { data[0] % 4 } else { 0 };
+    let res = match target_selector {
+        0 => scrypt(password, salt, &params, &mut result).is_ok(),
+        1 => Scrypt.verify_password(password, &hash).is_err(),
+        2 => Scrypt
+            .hash_password_customized(
+                password,
+                Some(Ident::new_unwrap("scrypt")),
+                None,
+                params,
+                salt_value,
+            )
+            .is_ok(),
+        3 => {
+            if let Some(random_params) = fuzzed_params(password) {
+                scrypt(password, salt, &random_params, &mut result).is_ok()
+            } else {
+                true
             }
         }
-    } else {
-        // Skip this iteration if the salt is invalid
-        return;
-    }
+        _ => unreachable!(),
+    };
+    assert!(res);
 });