Replace the custom SHA-2 implementation in enc_sha256.

2 files changed, 13 insertions, 204 deletions

diff --git a/modules/encryption/enc_sha2.cpp b/modules/encryption/enc_sha2.cpp
index 6770abe8d..31b055c6b 100644
--- a/modules/encryption/enc_sha2.cpp
+++ b/modules/encryption/enc_sha2.cpp
@@ -1,4 +1,4 @@
-/* Module for providing bcrypt hashing
+/* Module for providing SHA-2 hashing
  *
  * (C) 2003-2024 Anope Team
  * Contact us at team@anope.org
diff --git a/modules/encryption/enc_sha256.cpp b/modules/encryption/enc_sha256.cpp
index 0b883dc50..c9c3187e0 100644
--- a/modules/encryption/enc_sha256.cpp
+++ b/modules/encryption/enc_sha256.cpp
@@ -1,212 +1,17 @@
 /* This module generates and compares password hashes using SHA256 algorithms.
  *
- * If an intruder gets access to your system or uses a brute force attack,
- * salt will not provide much value.
- * IMPORTANT: DATA HASHES CANNOT BE "DECRYPTED" BACK TO PLAIN TEXT.
- *
- * Modified for Anope.
  * (C) 2003-2024 Anope Team
  * Contact us at team@anope.org
  *
- * Taken from InspIRCd (https://www.inspircd.org/),
- * see https://wiki.inspircd.org/Credits
+ * This program is free but copyrighted software; see the file COPYING for
+ * details.
  *
- * This program is free but copyrighted software; see
- * the file COPYING for details.
  */
 
-/* FIPS 180-2 SHA-224/256/384/512 implementation
- * Last update: 05/23/2005
- * Issue date:  04/30/2005
- *
- * Copyright (C) 2005 Olivier Gay <olivier.gay@a3.epfl.ch>
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. Neither the name of the project nor the names of its contributors
- *    may be used to endorse or promote products derived from this software
- *    without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
+#include "sha2/sha2.c"
 
 #include "module.h"
 
-static const unsigned SHA256_DIGEST_SIZE = 256 / 8;
-static const unsigned SHA256_BLOCK_SIZE = 512 / 8;
-
-inline static uint32_t SHFR(uint32_t x, uint32_t n) { return x >> n; }
-inline static uint32_t ROTR(uint32_t x, uint32_t n) { return (x >> n) | (x << ((sizeof(x) << 3) - n)); }
-inline static uint32_t CH(uint32_t x, uint32_t y, uint32_t z) { return (x & y) ^ (~x & z); }
-inline static uint32_t MAJ(uint32_t x, uint32_t y, uint32_t z) { return (x & y) ^ (x & z) ^ (y & z); }
-
-inline static uint32_t SHA256_F1(uint32_t x) { return ROTR(x, 2) ^ ROTR(x, 13) ^ ROTR(x, 22); }
-inline static uint32_t SHA256_F2(uint32_t x) { return ROTR(x, 6) ^ ROTR(x, 11) ^ ROTR(x, 25); }
-inline static uint32_t SHA256_F3(uint32_t x) { return ROTR(x, 7) ^ ROTR(x, 18) ^ SHFR(x, 3); }
-inline static uint32_t SHA256_F4(uint32_t x) { return ROTR(x, 17) ^ ROTR(x, 19) ^ SHFR(x, 10); }
-
-inline static void UNPACK32(unsigned x, unsigned char *str)
-{
-	str[3] = static_cast<uint8_t>(x);
-	str[2] = static_cast<uint8_t>(x >> 8);
-	str[1] = static_cast<uint8_t>(x >> 16);
-	str[0] = static_cast<uint8_t>(x >> 24);
-}
-
-inline static void PACK32(unsigned char *str, uint32_t &x)
-{
-	x = static_cast<uint32_t>(str[3]) | static_cast<uint32_t>(str[2]) << 8 | static_cast<uint32_t>(str[1]) << 16 | static_cast<uint32_t>(str[0]) << 24;
-}
-
-/* Macros used for loops unrolling */
-
-inline static void SHA256_SCR(uint32_t w[64], int i)
-{
-	w[i] = SHA256_F4(w[i - 2]) + w[i - 7] + SHA256_F3(w[i - 15]) + w[i - 16];
-}
-
-static const uint32_t sha256_h0[8] =
-{
-	0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a,
-	0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19
-};
-
-static const uint32_t sha256_k[64] =
-{
-	0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
-	0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
-	0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
-	0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
-	0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
-	0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
-	0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
-	0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
-	0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
-	0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
-	0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
-	0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
-	0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
-	0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
-	0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
-	0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
-};
-
-/** An sha256 context
- */
-class SHA256Context final
-{
-	void Transform(unsigned char *message, unsigned block_nb)
-	{
-		uint32_t w[64], wv[8];
-		unsigned char *sub_block;
-		for (unsigned i = 1; i <= block_nb; ++i)
-		{
-			int j;
-			sub_block = message + ((i - 1) << 6);
-
-			for (j = 0; j < 16; ++j)
-				PACK32(&sub_block[j << 2], w[j]);
-			for (j = 16; j < 64; ++j)
-				SHA256_SCR(w, j);
-			for (j = 0; j < 8; ++j)
-				wv[j] = this->h[j];
-			for (j = 0; j < 64; ++j)
-			{
-				uint32_t t1 = wv[7] + SHA256_F2(wv[4]) + CH(wv[4], wv[5], wv[6]) + sha256_k[j] + w[j];
-				uint32_t t2 = SHA256_F1(wv[0]) + MAJ(wv[0], wv[1], wv[2]);
-				wv[7] = wv[6];
-				wv[6] = wv[5];
-				wv[5] = wv[4];
-				wv[4] = wv[3] + t1;
-				wv[3] = wv[2];
-				wv[2] = wv[1];
-				wv[1] = wv[0];
-				wv[0] = t1 + t2;
-			}
-			for (j = 0; j < 8; ++j)
-				this->h[j] += wv[j];
-		}
-	}
-
-	unsigned tot_len;
-	unsigned len;
-	unsigned char block[2 * SHA256_BLOCK_SIZE];
-	uint32_t h[8];
-
-public:
-	SHA256Context()
-	{
-		for (int i = 0; i < 8; ++i)
-			this->h[i] = sha256_h0[i];
-
-		this->tot_len = 0;
-		this->len = 0;
-		memset(this->block, 0, sizeof(this->block));
-	}
-
-	void SetIV(uint32_t* iv)
-	{
-		for (int i = 0; i < 8; ++i)
-			this->h[i] = iv[i];
-	}
-
-	void Update(const unsigned char *message, size_t mlen)
-	{
-		unsigned tmp_len = SHA256_BLOCK_SIZE - this->len, rem_len = mlen < tmp_len ? mlen : tmp_len;
-
-		memcpy(&this->block[this->len], message, rem_len);
-		if (this->len + mlen < SHA256_BLOCK_SIZE)
-		{
-			this->len += mlen;
-			return;
-		}
-		unsigned new_len = mlen - rem_len, block_nb = new_len / SHA256_BLOCK_SIZE;
-		unsigned char *shifted_message = new unsigned char[mlen - rem_len];
-		memcpy(shifted_message, message + rem_len, mlen - rem_len);
-		this->Transform(this->block, 1);
-		this->Transform(shifted_message, block_nb);
-		rem_len = new_len % SHA256_BLOCK_SIZE;
-		memcpy(this->block, &shifted_message[block_nb << 6], rem_len);
-		delete [] shifted_message;
-		this->len = rem_len;
-		this->tot_len += (block_nb + 1) << 6;
-	}
-
-	Anope::string Finalize()
-	{
-		unsigned block_nb = 1 + ((SHA256_BLOCK_SIZE - 9) < (this->len % SHA256_BLOCK_SIZE));
-		unsigned len_b = (this->tot_len + this->len) << 3;
-		unsigned pm_len = block_nb << 6;
-		memset(this->block + this->len, 0, pm_len - this->len);
-		this->block[this->len] = 0x80;
-		UNPACK32(len_b, this->block + pm_len - 4);
-		this->Transform(this->block, block_nb);
-		unsigned char digest[SHA256_DIGEST_SIZE];
-		memset(digest, 0, sizeof(digest));
-		for (int i = 0 ; i < 8; ++i)
-			UNPACK32(this->h[i], &digest[i << 2]);
-
-		return Anope::string(reinterpret_cast<const char *>(&digest), sizeof(digest));
-	}
-};
-
 class ESHA256 final
 	: public Module
 {
@@ -240,7 +45,7 @@ private:
 		char buf2[33];
 		Anope::Unhex(buf, buf2, sizeof(buf2));
 		for (int i = 0 ; i < 8; ++i)
-			PACK32(reinterpret_cast<unsigned char *>(&buf2[i << 2]), iv[i]);
+			PACK32(reinterpret_cast<unsigned char *>(&buf2[i << 2]), &iv[i]);
 	}
 
 public:
@@ -259,10 +64,14 @@ public:
 		else
 			use_iv = false;
 
-		SHA256Context ctx;
-		ctx.SetIV(this->iv);
-		ctx.Update(reinterpret_cast<const unsigned char *>(src.c_str()), src.length());
-		auto hash = ctx.Finalize();
+		sha256_ctx ctx;
+		sha256_init(&ctx);
+		for (size_t i = 0; i < 8; ++i)
+			ctx.h[i] = iv[i];
+		sha256_update(&ctx, reinterpret_cast<const unsigned char *>(src.data()), src.length());
+		unsigned char digest[SHA256_DIGEST_SIZE];
+		sha256_final(&ctx, digest);
+		Anope::string hash(reinterpret_cast<const char *>(&digest), sizeof(digest));
 
 		std::stringstream buf;
 		buf << "sha256:" << Anope::Hex(hash) << ":" << GetIVString();