Atmosphere/libraries/libvapours/source/crypto/impl/crypto_sha256_impl.arch.generic.cpp

261 lines
9.2 KiB
C++

/*
* Copyright (c) Atmosphère-NX
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <vapours.hpp>
namespace ams::crypto::impl {
namespace {
alignas(Sha256Impl::BlockSize) constexpr const u32 RoundConstants[0x40] = {
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,
};
constexpr ALWAYS_INLINE u32 Choose(u32 x, u32 y, u32 z) {
return (x & y) ^ ((~x) & z);
}
constexpr ALWAYS_INLINE u32 Majority(u32 x, u32 y, u32 z) {
return (x & y) ^ (x & z) ^ (y & z);
}
constexpr ALWAYS_INLINE u32 LargeSigma0(u32 x) {
return util::RotateRight<u32>(x, 2) ^ util::RotateRight<u32>(x, 13) ^ util::RotateRight<u32>(x, 22);
}
constexpr ALWAYS_INLINE u32 LargeSigma1(u32 x) {
return util::RotateRight<u32>(x, 6) ^ util::RotateRight<u32>(x, 11) ^ util::RotateRight<u32>(x, 25);
}
constexpr ALWAYS_INLINE u32 SmallSigma0(u32 x) {
return util::RotateRight<u32>(x, 7) ^ util::RotateRight<u32>(x, 18) ^ (x >> 3);
}
constexpr ALWAYS_INLINE u32 SmallSigma1(u32 x) {
return util::RotateRight<u32>(x, 17) ^ util::RotateRight<u32>(x, 19) ^ (x >> 10);
}
}
void Sha256Impl::Initialize() {
/* Reset buffered bytes/bits. */
m_buffered_bytes = 0;
m_bits_consumed = 0;
/* Set intermediate hash. */
m_intermediate_hash[0] = 0x6A09E667;
m_intermediate_hash[1] = 0xBB67AE85;
m_intermediate_hash[2] = 0x3C6EF372;
m_intermediate_hash[3] = 0xA54FF53A;
m_intermediate_hash[4] = 0x510E527F;
m_intermediate_hash[5] = 0x9B05688C;
m_intermediate_hash[6] = 0x1F83D9AB;
m_intermediate_hash[7] = 0x5BE0CD19;
/* Set state. */
m_state = State_Initialized;
}
void Sha256Impl::Update(const void *data, size_t size) {
/* Verify we're in a state to update. */
AMS_ASSERT(m_state == State_Initialized);
/* Advance our input bit count. */
m_bits_consumed += BITSIZEOF(u8) * (((m_buffered_bytes + size) / BlockSize) * BlockSize);
/* Process anything we have buffered. */
const u8 *data8 = static_cast<const u8 *>(data);
size_t remaining = size;
if (m_buffered_bytes > 0) {
const size_t copy_size = std::min(BlockSize - m_buffered_bytes, remaining);
std::memcpy(m_buffer + m_buffered_bytes, data8, copy_size);
data8 += copy_size;
remaining -= copy_size;
m_buffered_bytes += copy_size;
/* Process a block, if we filled one. */
if (m_buffered_bytes == BlockSize) {
this->ProcessBlock(m_buffer);
m_buffered_bytes = 0;
}
}
/* Process blocks, if we have any. */
while (remaining >= BlockSize) {
this->ProcessBlock(data8);
data8 += BlockSize;
remaining -= BlockSize;
}
/* Copy any leftover data to our buffer. */
if (remaining > 0) {
m_buffered_bytes = remaining;
std::memcpy(m_buffer, data8, remaining);
}
}
void Sha256Impl::GetHash(void *dst, size_t size) {
/* Verify we're in a state to get hash. */
AMS_ASSERT(m_state == State_Initialized || m_state == State_Done);
AMS_ASSERT(size >= HashSize);
AMS_UNUSED(size);
/* If we need to, process the last block. */
if (m_state == State_Initialized) {
this->ProcessLastBlock();
m_state = State_Done;
}
/* Copy the output hash. */
if constexpr (util::IsLittleEndian()) {
static_assert(HashSize % sizeof(u32) == 0);
u32 *dst_32 = static_cast<u32 *>(dst);
for (size_t i = 0; i < HashSize / sizeof(u32); ++i) {
dst_32[i] = util::LoadBigEndian<u32>(m_intermediate_hash + i);
}
} else {
std::memcpy(dst, m_intermediate_hash, HashSize);
}
}
void Sha256Impl::InitializeWithContext(const Sha256Context *context) {
/* Copy state in from the context. */
std::memcpy(m_intermediate_hash, context->intermediate_hash, sizeof(m_intermediate_hash));
m_bits_consumed = context->bits_consumed;
/* Reset other fields. */
m_buffered_bytes = 0;
m_state = State_Initialized;
}
size_t Sha256Impl::GetContext(Sha256Context *context) const {
/* Check our state. */
AMS_ASSERT(m_state == State_Initialized);
/* Copy out the context. */
std::memcpy(context->intermediate_hash, m_intermediate_hash, sizeof(context->intermediate_hash));
context->bits_consumed = m_bits_consumed;
return m_buffered_bytes;
}
void Sha256Impl::ProcessBlock(const void *data) {
/* Load work variables. */
u32 a = m_intermediate_hash[0];
u32 b = m_intermediate_hash[1];
u32 c = m_intermediate_hash[2];
u32 d = m_intermediate_hash[3];
u32 e = m_intermediate_hash[4];
u32 f = m_intermediate_hash[5];
u32 g = m_intermediate_hash[6];
u32 h = m_intermediate_hash[7];
u32 tmp[2];
size_t i;
/* Copy the input. */
u32 w[64];
if constexpr (util::IsLittleEndian()) {
static_assert(BlockSize % sizeof(u32) == 0);
const u32 *src_32 = static_cast<const u32 *>(data);
for (size_t i = 0; i < BlockSize / sizeof(u32); ++i) {
w[i] = util::LoadBigEndian<u32>(src_32 + i);
}
} else {
std::memcpy(w, data, BlockSize);
}
/* Initialize the rest of w. */
for (i = BlockSize / sizeof(u32); i < util::size(w); ++i) {
const u32 *prev = w + (i - BlockSize / sizeof(u32));
w[i] = prev[0] + SmallSigma0(prev[1]) + prev[9] + SmallSigma1(prev[14]);
}
/* Perform rounds. */
for (i = 0; i < 64; ++i) {
tmp[0] = h + LargeSigma1(e) + Choose(e, f, g) + RoundConstants[i] + w[i];
tmp[1] = LargeSigma0(a) + Majority(a, b, c);
h = g;
g = f;
f = e;
e = d + tmp[0];
d = c;
c = b;
b = a;
a = tmp[0] + tmp[1];
}
/* Update intermediate hash. */
m_intermediate_hash[0] += a;
m_intermediate_hash[1] += b;
m_intermediate_hash[2] += c;
m_intermediate_hash[3] += d;
m_intermediate_hash[4] += e;
m_intermediate_hash[5] += f;
m_intermediate_hash[6] += g;
m_intermediate_hash[7] += h;
}
void Sha256Impl::ProcessLastBlock() {
/* Setup the final block. */
constexpr const auto BlockSizeWithoutSizeField = BlockSize - sizeof(u64);
/* Increment our bits consumed. */
m_bits_consumed += BITSIZEOF(u8) * m_buffered_bytes;
/* Add 0x80 terminator. */
m_buffer[m_buffered_bytes++] = 0x80;
/* If we can process the size field directly, do so, otherwise set up to process it. */
if (m_buffered_bytes <= BlockSizeWithoutSizeField) {
/* Clear up to size field. */
std::memset(m_buffer + m_buffered_bytes, 0, BlockSizeWithoutSizeField - m_buffered_bytes);
} else {
/* Consume full block */
std::memset(m_buffer + m_buffered_bytes, 0, BlockSize - m_buffered_bytes);
this->ProcessBlock(m_buffer);
/* Clear up to size field. */
std::memset(m_buffer, 0, BlockSizeWithoutSizeField);
}
/* Store the size field. */
util::StoreBigEndian<u64>(reinterpret_cast<u64 *>(m_buffer + BlockSizeWithoutSizeField), m_bits_consumed);
/* Process the final block. */
this->ProcessBlock(m_buffer);
}
}