From 4304132f8f8c81e49c478c777ad420b4784be517 Mon Sep 17 00:00:00 2001 From: ImagicTheCat Date: Wed, 24 May 2023 16:09:34 +0200 Subject: [PATCH] Fix/improve SHA1 hashing. --- src/modules/data/HashFunction.cpp | 26 +++++++++++--------------- 1 file changed, 11 insertions(+), 15 deletions(-) diff --git a/src/modules/data/HashFunction.cpp b/src/modules/data/HashFunction.cpp index 79f4d25ef..49c5d970c 100644 --- a/src/modules/data/HashFunction.cpp +++ b/src/modules/data/HashFunction.cpp @@ -204,29 +204,25 @@ public: 0x67452301, 0xEFCDAB89, 0x98BADCFE, 0x10325476, 0xC3D2E1F0 }; - //Do the required padding (MD5, SHA1 and SHA2 use the same padding) - uint64 paddedLength = length + 1; //Consider the appended bit - if (paddedLength % 64 < 56) - paddedLength += 56 - paddedLength % 64; - if (paddedLength % 64 > 56) - paddedLength += 120 - paddedLength % 64; + // Compute final padded length, accounting for the appended bit (byte) and size + uint64 paddedLength = extend_multiple(length + 1 + 8, 64); - uint8 *padded = new uint8[paddedLength + 8]; + uint32 *padded = new uint32[paddedLength / 4]; memcpy(padded, input, length); - memset(padded + length, 0, paddedLength - length); - padded[length] = 0x80; + memset(((uint8*)padded) + length, 0, paddedLength - length); + *(((uint8*)padded) + length) = 0x80; // append bit - // Now we need the length in bits (big endian) - length *= 8; - for (int i = 0; i < 8; ++i, ++paddedLength) - padded[paddedLength] = (length >> (56 - i * 8)) & 0xFF; + // Append length in bits (big endian) + uint64 bit_length = length * 8; + for (int i = 0; i < 8; ++i) + *(((uint8*)padded) + (paddedLength - 8 + i)) = (bit_length >> (56 - i * 8)) & 0xFF; // Allocate our extended words uint32 words[80]; - for (uint64 i = 0; i < paddedLength; i += 64) + for (uint64 i = 0; i < paddedLength/4; i += 16) { - uint32 *chunk = (uint32*) &padded[i]; + uint32 *chunk = &padded[i]; for (int j = 0; j < 16; j++) { char *c = (char*) &words[j];