From 450403883b2c70bda931cfaeffd02b400517d1cb Mon Sep 17 00:00:00 2001
From: Geoffrey White <40627776+geoffw0@users.noreply.github.com>
Date: Mon, 1 Dec 2025 11:55:18 +0000
Subject: [PATCH] Rust: Add test cases for a small number of FPs we see.

---
 .../HardcodedCryptographicValue.expected      | 71 ++++++++++++-------
 .../security/CWE-798/test_heuristic.rs        | 11 ++-
 2 files changed, 54 insertions(+), 28 deletions(-)

diff --git a/rust/ql/test/query-tests/security/CWE-798/HardcodedCryptographicValue.expected b/rust/ql/test/query-tests/security/CWE-798/HardcodedCryptographicValue.expected
index 6aa266fd48a..f0e75e6a51a 100644
--- a/rust/ql/test/query-tests/security/CWE-798/HardcodedCryptographicValue.expected
+++ b/rust/ql/test/query-tests/security/CWE-798/HardcodedCryptographicValue.expected
@@ -10,41 +10,45 @@
 | test_cookie.rs:21:28:21:34 | [0; 64] | test_cookie.rs:21:28:21:34 | [0; 64] | test_cookie.rs:22:16:22:24 | ...::from | This hard-coded value is used as $@. | test_cookie.rs:22:16:22:24 | ...::from | a key |
 | test_cookie.rs:38:28:38:36 | [0u8; 64] | test_cookie.rs:38:28:38:36 | [0u8; 64] | test_cookie.rs:42:14:42:32 | ...::from | This hard-coded value is used as $@. | test_cookie.rs:42:14:42:32 | ...::from | a key |
 | test_cookie.rs:49:23:49:25 | 0u8 | test_cookie.rs:49:23:49:25 | 0u8 | test_cookie.rs:53:14:53:32 | ...::from | This hard-coded value is used as $@. | test_cookie.rs:53:14:53:32 | ...::from | a key |
-| test_heuristic.rs:40:31:40:38 | [0u8; 16] | test_heuristic.rs:40:31:40:38 | [0u8; 16] | test_heuristic.rs:41:41:41:48 | const_iv | This hard-coded value is used as $@. | test_heuristic.rs:41:41:41:48 | const_iv | an initialization vector |
-| test_heuristic.rs:59:30:59:37 | "secret" | test_heuristic.rs:59:30:59:37 | "secret" | test_heuristic.rs:59:30:59:37 | "secret" | This hard-coded value is used as $@. | test_heuristic.rs:59:30:59:37 | "secret" | a password |
-| test_heuristic.rs:60:20:60:27 | [0u8; 16] | test_heuristic.rs:60:20:60:27 | [0u8; 16] | test_heuristic.rs:60:19:60:27 | &... | This hard-coded value is used as $@. | test_heuristic.rs:60:19:60:27 | &... | a nonce |
-| test_heuristic.rs:61:31:61:38 | [0u8; 16] | test_heuristic.rs:61:31:61:38 | [0u8; 16] | test_heuristic.rs:61:30:61:38 | &... | This hard-coded value is used as $@. | test_heuristic.rs:61:30:61:38 | &... | a salt |
+| test_heuristic.rs:44:31:44:38 | [0u8; 16] | test_heuristic.rs:44:31:44:38 | [0u8; 16] | test_heuristic.rs:45:41:45:48 | const_iv | This hard-coded value is used as $@. | test_heuristic.rs:45:41:45:48 | const_iv | an initialization vector |
+| test_heuristic.rs:63:30:63:37 | "secret" | test_heuristic.rs:63:30:63:37 | "secret" | test_heuristic.rs:63:30:63:37 | "secret" | This hard-coded value is used as $@. | test_heuristic.rs:63:30:63:37 | "secret" | a password |
+| test_heuristic.rs:64:20:64:27 | [0u8; 16] | test_heuristic.rs:64:20:64:27 | [0u8; 16] | test_heuristic.rs:64:19:64:27 | &... | This hard-coded value is used as $@. | test_heuristic.rs:64:19:64:27 | &... | a nonce |
+| test_heuristic.rs:65:31:65:38 | [0u8; 16] | test_heuristic.rs:65:31:65:38 | [0u8; 16] | test_heuristic.rs:65:30:65:38 | &... | This hard-coded value is used as $@. | test_heuristic.rs:65:30:65:38 | &... | a salt |
+| test_heuristic.rs:67:22:67:22 | 0 | test_heuristic.rs:67:22:67:22 | 0 | test_heuristic.rs:67:22:67:22 | 0 | This hard-coded value is used as $@. | test_heuristic.rs:67:22:67:22 | 0 | a salt |
+| test_heuristic.rs:69:32:69:32 | 1 | test_heuristic.rs:69:32:69:32 | 1 | test_heuristic.rs:69:22:69:32 | ... + ... | This hard-coded value is used as $@. | test_heuristic.rs:69:22:69:32 | ... + ... | a salt |
+| test_heuristic.rs:70:34:70:35 | 32 | test_heuristic.rs:70:34:70:35 | 32 | test_heuristic.rs:70:22:70:62 | ... ^ ... | This hard-coded value is used as $@. | test_heuristic.rs:70:22:70:62 | ... ^ ... | a salt |
+| test_heuristic.rs:70:52:70:61 | 0xFFFFFFFF | test_heuristic.rs:70:52:70:61 | 0xFFFFFFFF | test_heuristic.rs:70:22:70:62 | ... ^ ... | This hard-coded value is used as $@. | test_heuristic.rs:70:22:70:62 | ... ^ ... | a salt |
 edges
 | test_cipher.rs:18:9:18:14 | const1 [&ref] | test_cipher.rs:19:73:19:78 | const1 [&ref] | provenance |  |
 | test_cipher.rs:18:28:18:36 | &... [&ref] | test_cipher.rs:18:9:18:14 | const1 [&ref] | provenance |  |
 | test_cipher.rs:18:29:18:36 | [0u8; 16] | test_cipher.rs:18:28:18:36 | &... [&ref] | provenance |  |
 | test_cipher.rs:19:49:19:79 | ...::from_slice(...) [&ref] | test_cipher.rs:19:30:19:47 | ...::new | provenance | MaD:3 Sink:MaD:3 |
-| test_cipher.rs:19:73:19:78 | const1 [&ref] | test_cipher.rs:19:49:19:79 | ...::from_slice(...) [&ref] | provenance | MaD:9 |
+| test_cipher.rs:19:73:19:78 | const1 [&ref] | test_cipher.rs:19:49:19:79 | ...::from_slice(...) [&ref] | provenance | MaD:10 |
 | test_cipher.rs:25:9:25:14 | const4 [&ref] | test_cipher.rs:26:66:26:71 | const4 [&ref] | provenance |  |
 | test_cipher.rs:25:28:25:36 | &... [&ref] | test_cipher.rs:25:9:25:14 | const4 [&ref] | provenance |  |
 | test_cipher.rs:25:29:25:36 | [0u8; 16] | test_cipher.rs:25:28:25:36 | &... [&ref] | provenance |  |
 | test_cipher.rs:26:42:26:72 | ...::from_slice(...) [&ref] | test_cipher.rs:26:30:26:40 | ...::new | provenance | MaD:4 Sink:MaD:4 |
-| test_cipher.rs:26:66:26:71 | const4 [&ref] | test_cipher.rs:26:42:26:72 | ...::from_slice(...) [&ref] | provenance | MaD:9 |
+| test_cipher.rs:26:66:26:71 | const4 [&ref] | test_cipher.rs:26:42:26:72 | ...::from_slice(...) [&ref] | provenance | MaD:10 |
 | test_cipher.rs:29:9:29:14 | const5 [&ref] | test_cipher.rs:30:95:30:100 | const5 [&ref] | provenance |  |
 | test_cipher.rs:29:28:29:36 | &... [&ref] | test_cipher.rs:29:9:29:14 | const5 [&ref] | provenance |  |
 | test_cipher.rs:29:29:29:36 | [0u8; 16] | test_cipher.rs:29:28:29:36 | &... [&ref] | provenance |  |
 | test_cipher.rs:30:72:30:101 | ...::from_slice(...) [&ref] | test_cipher.rs:30:30:30:40 | ...::new | provenance | MaD:5 Sink:MaD:5 |
-| test_cipher.rs:30:95:30:100 | const5 [&ref] | test_cipher.rs:30:72:30:101 | ...::from_slice(...) [&ref] | provenance | MaD:9 |
+| test_cipher.rs:30:95:30:100 | const5 [&ref] | test_cipher.rs:30:72:30:101 | ...::from_slice(...) [&ref] | provenance | MaD:10 |
 | test_cipher.rs:37:9:37:14 | const7 | test_cipher.rs:38:74:38:79 | const7 | provenance |  |
 | test_cipher.rs:37:27:37:74 | [...] | test_cipher.rs:37:9:37:14 | const7 | provenance |  |
 | test_cipher.rs:38:49:38:80 | ...::from_slice(...) [&ref] | test_cipher.rs:38:30:38:47 | ...::new | provenance | MaD:3 Sink:MaD:3 |
-| test_cipher.rs:38:73:38:79 | &const7 [&ref] | test_cipher.rs:38:49:38:80 | ...::from_slice(...) [&ref] | provenance | MaD:9 |
+| test_cipher.rs:38:73:38:79 | &const7 [&ref] | test_cipher.rs:38:49:38:80 | ...::from_slice(...) [&ref] | provenance | MaD:10 |
 | test_cipher.rs:38:74:38:79 | const7 | test_cipher.rs:38:73:38:79 | &const7 [&ref] | provenance |  |
 | test_cipher.rs:41:9:41:14 | const8 [&ref] | test_cipher.rs:42:73:42:78 | const8 [&ref] | provenance |  |
 | test_cipher.rs:41:28:41:76 | &... [&ref] | test_cipher.rs:41:9:41:14 | const8 [&ref] | provenance |  |
 | test_cipher.rs:41:29:41:76 | [...] | test_cipher.rs:41:28:41:76 | &... [&ref] | provenance |  |
 | test_cipher.rs:42:49:42:79 | ...::from_slice(...) [&ref] | test_cipher.rs:42:30:42:47 | ...::new | provenance | MaD:3 Sink:MaD:3 |
-| test_cipher.rs:42:73:42:78 | const8 [&ref] | test_cipher.rs:42:49:42:79 | ...::from_slice(...) [&ref] | provenance | MaD:9 |
+| test_cipher.rs:42:73:42:78 | const8 [&ref] | test_cipher.rs:42:49:42:79 | ...::from_slice(...) [&ref] | provenance | MaD:10 |
 | test_cipher.rs:50:9:50:15 | const10 [element] | test_cipher.rs:51:75:51:81 | const10 [element] | provenance |  |
 | test_cipher.rs:50:37:50:52 | ...::zeroed | test_cipher.rs:50:37:50:54 | ...::zeroed(...) [element] | provenance | Src:MaD:7  |
 | test_cipher.rs:50:37:50:54 | ...::zeroed(...) [element] | test_cipher.rs:50:9:50:15 | const10 [element] | provenance |  |
 | test_cipher.rs:51:50:51:82 | ...::from_slice(...) [&ref, element] | test_cipher.rs:51:31:51:48 | ...::new | provenance | MaD:3 Sink:MaD:3 Sink:MaD:3 |
-| test_cipher.rs:51:74:51:81 | &const10 [&ref, element] | test_cipher.rs:51:50:51:82 | ...::from_slice(...) [&ref, element] | provenance | MaD:9 |
+| test_cipher.rs:51:74:51:81 | &const10 [&ref, element] | test_cipher.rs:51:50:51:82 | ...::from_slice(...) [&ref, element] | provenance | MaD:10 |
 | test_cipher.rs:51:75:51:81 | const10 [element] | test_cipher.rs:51:74:51:81 | &const10 [&ref, element] | provenance |  |
 | test_cipher.rs:73:9:73:14 | const2 [&ref] | test_cipher.rs:74:46:74:51 | const2 [&ref] | provenance |  |
 | test_cipher.rs:73:18:73:26 | &... [&ref] | test_cipher.rs:73:9:73:14 | const2 [&ref] | provenance |  |
@@ -63,14 +67,19 @@ edges
 | test_cookie.rs:38:28:38:36 | [0u8; 64] | test_cookie.rs:38:18:38:37 | ...::from(...) | provenance | MaD:8 |
 | test_cookie.rs:42:34:42:39 | array2 | test_cookie.rs:42:14:42:32 | ...::from | provenance | MaD:2 Sink:MaD:2 |
 | test_cookie.rs:49:9:49:14 | array3 [element] | test_cookie.rs:53:34:53:39 | array3 [element] | provenance |  |
-| test_cookie.rs:49:23:49:25 | 0u8 | test_cookie.rs:49:23:49:29 | ...::from_elem(...) [element] | provenance | MaD:10 |
+| test_cookie.rs:49:23:49:25 | 0u8 | test_cookie.rs:49:23:49:29 | ...::from_elem(...) [element] | provenance | MaD:11 |
 | test_cookie.rs:49:23:49:29 | ...::from_elem(...) [element] | test_cookie.rs:49:9:49:14 | array3 [element] | provenance |  |
 | test_cookie.rs:53:34:53:39 | array3 [element] | test_cookie.rs:53:14:53:32 | ...::from | provenance | MaD:2 Sink:MaD:2 |
-| test_heuristic.rs:40:9:40:16 | const_iv [&ref] | test_heuristic.rs:41:41:41:48 | const_iv | provenance |  |
-| test_heuristic.rs:40:30:40:38 | &... [&ref] | test_heuristic.rs:40:9:40:16 | const_iv [&ref] | provenance |  |
-| test_heuristic.rs:40:31:40:38 | [0u8; 16] | test_heuristic.rs:40:30:40:38 | &... [&ref] | provenance |  |
-| test_heuristic.rs:60:20:60:27 | [0u8; 16] | test_heuristic.rs:60:19:60:27 | &... | provenance |  |
-| test_heuristic.rs:61:31:61:38 | [0u8; 16] | test_heuristic.rs:61:30:61:38 | &... | provenance |  |
+| test_heuristic.rs:44:9:44:16 | const_iv [&ref] | test_heuristic.rs:45:41:45:48 | const_iv | provenance |  |
+| test_heuristic.rs:44:30:44:38 | &... [&ref] | test_heuristic.rs:44:9:44:16 | const_iv [&ref] | provenance |  |
+| test_heuristic.rs:44:31:44:38 | [0u8; 16] | test_heuristic.rs:44:30:44:38 | &... [&ref] | provenance |  |
+| test_heuristic.rs:64:20:64:27 | [0u8; 16] | test_heuristic.rs:64:19:64:27 | &... | provenance |  |
+| test_heuristic.rs:65:31:65:38 | [0u8; 16] | test_heuristic.rs:65:30:65:38 | &... | provenance |  |
+| test_heuristic.rs:69:32:69:32 | 1 | test_heuristic.rs:69:22:69:32 | ... + ... | provenance |  |
+| test_heuristic.rs:70:23:70:35 | ... << ... | test_heuristic.rs:70:22:70:62 | ... ^ ... | provenance |  |
+| test_heuristic.rs:70:34:70:35 | 32 | test_heuristic.rs:70:22:70:62 | ... ^ ... | provenance |  |
+| test_heuristic.rs:70:34:70:35 | 32 | test_heuristic.rs:70:23:70:35 | ... << ... | provenance | MaD:9 |
+| test_heuristic.rs:70:52:70:61 | 0xFFFFFFFF | test_heuristic.rs:70:22:70:62 | ... ^ ... | provenance |  |
 models
 | 1 | Sink: <_ as crypto_common::KeyInit>::new_from_slice; Argument[0]; credentials-key |
 | 2 | Sink: <biscotti::crypto::master::Key>::from; Argument[0]; credentials-key |
@@ -80,8 +89,9 @@ models
 | 6 | Sink: <cookie::secure::key::Key>::from; Argument[0].Reference; credentials-key |
 | 7 | Source: core::mem::zeroed; ReturnValue.Element; constant-source |
 | 8 | Summary: <_ as core::convert::From>::from; Argument[0]; ReturnValue; taint |
-| 9 | Summary: <generic_array::GenericArray>::from_slice; Argument[0].Reference; ReturnValue.Reference; value |
-| 10 | Summary: alloc::vec::from_elem; Argument[0]; ReturnValue.Element; value |
+| 9 | Summary: <core::u64 as core::ops::bit::Shl>::shl; Argument[0]; ReturnValue; taint |
+| 10 | Summary: <generic_array::GenericArray>::from_slice; Argument[0].Reference; ReturnValue.Reference; value |
+| 11 | Summary: alloc::vec::from_elem; Argument[0]; ReturnValue.Element; value |
 nodes
 | test_cipher.rs:18:9:18:14 | const1 [&ref] | semmle.label | const1 [&ref] |
 | test_cipher.rs:18:28:18:36 | &... [&ref] | semmle.label | &... [&ref] |
@@ -145,13 +155,20 @@ nodes
 | test_cookie.rs:49:23:49:29 | ...::from_elem(...) [element] | semmle.label | ...::from_elem(...) [element] |
 | test_cookie.rs:53:14:53:32 | ...::from | semmle.label | ...::from |
 | test_cookie.rs:53:34:53:39 | array3 [element] | semmle.label | array3 [element] |
-| test_heuristic.rs:40:9:40:16 | const_iv [&ref] | semmle.label | const_iv [&ref] |
-| test_heuristic.rs:40:30:40:38 | &... [&ref] | semmle.label | &... [&ref] |
-| test_heuristic.rs:40:31:40:38 | [0u8; 16] | semmle.label | [0u8; 16] |
-| test_heuristic.rs:41:41:41:48 | const_iv | semmle.label | const_iv |
-| test_heuristic.rs:59:30:59:37 | "secret" | semmle.label | "secret" |
-| test_heuristic.rs:60:19:60:27 | &... | semmle.label | &... |
-| test_heuristic.rs:60:20:60:27 | [0u8; 16] | semmle.label | [0u8; 16] |
-| test_heuristic.rs:61:30:61:38 | &... | semmle.label | &... |
-| test_heuristic.rs:61:31:61:38 | [0u8; 16] | semmle.label | [0u8; 16] |
+| test_heuristic.rs:44:9:44:16 | const_iv [&ref] | semmle.label | const_iv [&ref] |
+| test_heuristic.rs:44:30:44:38 | &... [&ref] | semmle.label | &... [&ref] |
+| test_heuristic.rs:44:31:44:38 | [0u8; 16] | semmle.label | [0u8; 16] |
+| test_heuristic.rs:45:41:45:48 | const_iv | semmle.label | const_iv |
+| test_heuristic.rs:63:30:63:37 | "secret" | semmle.label | "secret" |
+| test_heuristic.rs:64:19:64:27 | &... | semmle.label | &... |
+| test_heuristic.rs:64:20:64:27 | [0u8; 16] | semmle.label | [0u8; 16] |
+| test_heuristic.rs:65:30:65:38 | &... | semmle.label | &... |
+| test_heuristic.rs:65:31:65:38 | [0u8; 16] | semmle.label | [0u8; 16] |
+| test_heuristic.rs:67:22:67:22 | 0 | semmle.label | 0 |
+| test_heuristic.rs:69:22:69:32 | ... + ... | semmle.label | ... + ... |
+| test_heuristic.rs:69:32:69:32 | 1 | semmle.label | 1 |
+| test_heuristic.rs:70:22:70:62 | ... ^ ... | semmle.label | ... ^ ... |
+| test_heuristic.rs:70:23:70:35 | ... << ... | semmle.label | ... << ... |
+| test_heuristic.rs:70:34:70:35 | 32 | semmle.label | 32 |
+| test_heuristic.rs:70:52:70:61 | 0xFFFFFFFF | semmle.label | 0xFFFFFFFF |
 subpaths
diff --git a/rust/ql/test/query-tests/security/CWE-798/test_heuristic.rs b/rust/ql/test/query-tests/security/CWE-798/test_heuristic.rs
index 851e90dd6e0..f8f16a16d12 100644
--- a/rust/ql/test/query-tests/security/CWE-798/test_heuristic.rs
+++ b/rust/ql/test/query-tests/security/CWE-798/test_heuristic.rs
@@ -29,9 +29,13 @@ impl MyCryptor {
     fn encrypt(&self, plaintext: &str, salt: &[u8;16]) {
         // ...
     }
+
+    fn set_salt_u64(&self, salt: u64) {
+        // ...
+    }
 }
 
-fn test(var_string: &str, var_data: &[u8;16]) {
+fn test(var_string: &str, var_data: &[u8;16], var_u64: u64) {
     encrypt_with("plaintext", var_data, var_data);
 
     let const_key: &[u8;16] = &[0u8;16]; // $ MISSING: Alert[rust/hard-coded-cryptographic-value]
@@ -59,4 +63,9 @@ fn test(var_string: &str, var_data: &[u8;16]) {
     let mc2 = MyCryptor::new("secret"); // $ Alert[rust/hard-coded-cryptographic-value]
     mc2.set_nonce(&[0u8;16]); // $ Alert[rust/hard-coded-cryptographic-value]
     mc2.encrypt("plaintext", &[0u8;16]); // $ Alert[rust/hard-coded-cryptographic-value]
+
+    mc2.set_salt_u64(0); // $ Alert[rust/hard-coded-cryptographic-value]
+    mc2.set_salt_u64(var_u64);
+    mc2.set_salt_u64(var_u64 + 1); // $ SPURIOUS: Alert[rust/hard-coded-cryptographic-value]
+    mc2.set_salt_u64((var_u64 << 32) ^ (var_u64  & 0xFFFFFFFF)); // $ SPURIOUS: Alert[rust/hard-coded-cryptographic-value]
 }