Commit c1eff72c4a

Frank Denis <124872+jedisct1@users.noreply.github.com>
2025-08-15 15:09:06
crypto/aes_ocb.zig: actually check against test vectors (#24835)
And use the correct bit endianness for padding
1 parent e9eee8d
Changed files (1)
lib
std
lib/std/crypto/aes_ocb.zig
@@ -76,7 +76,7 @@ fn AesOcb(comptime Aes: anytype) type {
                 xorWith(&offset, lx.star);
                 var padded = [_]u8{0} ** 16;
                 @memcpy(padded[0..leftover], a[i * 16 ..][0..leftover]);
-                padded[leftover] = 1;
+                padded[leftover] = 0x80;
                 var e = xorBlocks(offset, padded);
                 aes_enc_ctx.encrypt(&e, &e);
                 xorWith(&sum, e);
@@ -259,6 +259,7 @@ fn xorWith(x: *Block, y: Block) void {
 }
 
 const hexToBytes = std.fmt.hexToBytes;
+const testing = std.testing;
 
 test "AesOcb test vector 1" {
     if (builtin.zig_backend == .stage2_c) return error.SkipZigTest;
@@ -296,6 +297,7 @@ test "AesOcb test vector 2" {
     var expected_tag: [tag.len]u8 = undefined;
     _ = try hexToBytes(&expected_tag, "C5CD9D1850C141E358649994EE701B68");
 
+    try testing.expectEqualSlices(u8, &expected_tag, &tag);
     var m: [0]u8 = undefined;
     try Aes128Ocb.decrypt(&m, &c, tag, &ad, nonce, k);
 }
@@ -319,6 +321,8 @@ test "AesOcb test vector 3" {
     _ = try hexToBytes(&expected_tag, "479AD363AC366B95A98CA5F3000B1479");
     _ = try hexToBytes(&expected_c, "4412923493C57D5DE0D700F753CCE0D1D2D95060122E9F15A5DDBFC5787E50B5CC55EE507BCB084E");
 
+    try testing.expectEqualSlices(u8, &expected_tag, &tag);
+    try testing.expectEqualSlices(u8, &expected_c, &c);
     var m2: [m.len]u8 = undefined;
     try Aes128Ocb.decrypt(&m2, &c, tag, "", nonce, k);
     assert(mem.eql(u8, &m, &m2));
@@ -331,19 +335,21 @@ test "AesOcb test vector 4" {
     var nonce: [Aes128Ocb.nonce_length]u8 = undefined;
     var tag: [Aes128Ocb.tag_length]u8 = undefined;
     var m: [40]u8 = undefined;
-    var ad = m;
     var c: [m.len]u8 = undefined;
     _ = try hexToBytes(&k, "000102030405060708090A0B0C0D0E0F");
     _ = try hexToBytes(&m, "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F2021222324252627");
-    _ = try hexToBytes(&nonce, "BBAA99887766554433221104");
+    _ = try hexToBytes(&nonce, "BBAA9988776655443322110D");
+    const ad = m;
 
     Aes128Ocb.encrypt(&c, &tag, &m, &ad, nonce, k);
 
     var expected_c: [c.len]u8 = undefined;
     var expected_tag: [tag.len]u8 = undefined;
-    _ = try hexToBytes(&expected_tag, "3AD7A4FF3835B8C5701C1CCEC8FC3358");
-    _ = try hexToBytes(&expected_c, "571D535B60B277188BE5147170A9A22C");
+    _ = try hexToBytes(&expected_tag, "ED07BA06A4A69483A7035490C5769E60");
+    _ = try hexToBytes(&expected_c, "D5CA91748410C1751FF8A2F618255B68A0A12E093FF454606E59F9C1D0DDC54B65E8628E568BAD7A");
 
+    try testing.expectEqualSlices(u8, &expected_tag, &tag);
+    try testing.expectEqualSlices(u8, &expected_c, &c);
     var m2: [m.len]u8 = undefined;
     try Aes128Ocb.decrypt(&m2, &c, tag, &ad, nonce, k);
     assert(mem.eql(u8, &m, &m2));