LibCrypto: Adjust DER length encoding to follow the spec

It says to always use the smallest possible length representation
Author: https://github.com/stelar7 Commit: 1be411cc73 Pull-request: https://github.com/SerenityOS/serenity/pull/23674 Issue: https://github.com/SerenityOS/serenity/issues/23657 Reviewed-by: https://github.com/ADKaster ✅
2025-06-10 01:51:03 +09:00 · 2024-03-22 10:10:41 +01:00 · 2024-03-22 10:10:41 +01:00 · 1be411cc73 · 2024-07-17 09:56:35 +09:00
commit 1be411cc73
parent 2e142105c9
1 changed files with 2 additions and 1 deletions
--- a/Userland/Libraries/LibCrypto/ASN1/DER.cpp
+++ b/Userland/Libraries/LibCrypto/ASN1/DER.cpp
@ -262,7 +262,8 @@ ErrorOr<void> Encoder::write_length(size_t value)
    if (value < 0x80)
        return write_byte(value);

-    size_t size = ceil_div(AK::ceil_log2(value), 3ul);
+    size_t size_in_bits = AK::ceil_log2(value);
+    size_t size = ceil_div(size_in_bits, 8ul);
    TRY(write_byte(0x80 | size));

    for (size_t i = 0; i < size; i++) {