Index: xz/src/liblzma/check/sha256.c |
=================================================================== |
--- xz/src/liblzma/check/sha256.c (revision 0) |
+++ xz/src/liblzma/check/sha256.c (revision 0) |
@@ -0,0 +1,201 @@ |
+/////////////////////////////////////////////////////////////////////////////// |
+// |
+/// \file sha256.c |
+/// \brief SHA-256 |
+/// |
+/// \todo Crypto++ has x86 ASM optimizations. They use SSE so if they |
+/// are imported to liblzma, SSE instructions need to be used |
+/// conditionally to keep the code working on older boxes. |
+/// We could also support using some external libary for SHA-256. |
+// |
+// This code is based on the code found from 7-Zip, which has a modified |
+// version of the SHA-256 found from Crypto++ <http://www.cryptopp.com/>. |
+// The code was modified a little to fit into liblzma. |
+// |
+// Authors: Kevin Springle |
+// Wei Dai |
+// Igor Pavlov |
+// Lasse Collin |
+// |
+// This file has been put into the public domain. |
+// You can do whatever you want with this file. |
+// |
+/////////////////////////////////////////////////////////////////////////////// |
+ |
+// Avoid bogus warnings in transform(). |
+#if (__GNUC__ == 4 && __GNUC_MINOR__ >= 2) || __GNUC__ > 4 |
+# pragma GCC diagnostic ignored "-Wuninitialized" |
+#endif |
+ |
+#include "check.h" |
+ |
+// At least on x86, GCC is able to optimize this to a rotate instruction. |
+#define rotr_32(num, amount) ((num) >> (amount) | (num) << (32 - (amount))) |
+ |
+#define blk0(i) (W[i] = data[i]) |
+#define blk2(i) (W[i & 15] += s1(W[(i - 2) & 15]) + W[(i - 7) & 15] \ |
+ + s0(W[(i - 15) & 15])) |
+ |
+#define Ch(x, y, z) (z ^ (x & (y ^ z))) |
+#define Maj(x, y, z) ((x & y) | (z & (x | y))) |
+ |
+#define a(i) T[(0 - i) & 7] |
+#define b(i) T[(1 - i) & 7] |
+#define c(i) T[(2 - i) & 7] |
+#define d(i) T[(3 - i) & 7] |
+#define e(i) T[(4 - i) & 7] |
+#define f(i) T[(5 - i) & 7] |
+#define g(i) T[(6 - i) & 7] |
+#define h(i) T[(7 - i) & 7] |
+ |
+#define R(i) \ |
+ h(i) += S1(e(i)) + Ch(e(i), f(i), g(i)) + SHA256_K[i + j] \ |
+ + (j ? blk2(i) : blk0(i)); \ |
+ d(i) += h(i); \ |
+ h(i) += S0(a(i)) + Maj(a(i), b(i), c(i)) |
+ |
+#define S0(x) (rotr_32(x, 2) ^ rotr_32(x, 13) ^ rotr_32(x, 22)) |
+#define S1(x) (rotr_32(x, 6) ^ rotr_32(x, 11) ^ rotr_32(x, 25)) |
+#define s0(x) (rotr_32(x, 7) ^ rotr_32(x, 18) ^ (x >> 3)) |
+#define s1(x) (rotr_32(x, 17) ^ rotr_32(x, 19) ^ (x >> 10)) |
+ |
+ |
+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, |
+}; |
+ |
+ |
+static void |
+transform(uint32_t state[static 8], const uint32_t data[static 16]) |
+{ |
+ uint32_t W[16]; |
+ uint32_t T[8]; |
+ |
+ // Copy state[] to working vars. |
+ memcpy(T, state, sizeof(T)); |
+ |
+ // 64 operations, partially loop unrolled |
+ for (unsigned int j = 0; j < 64; j += 16) { |
+ R( 0); R( 1); R( 2); R( 3); |
+ R( 4); R( 5); R( 6); R( 7); |
+ R( 8); R( 9); R(10); R(11); |
+ R(12); R(13); R(14); R(15); |
+ } |
+ |
+ // Add the working vars back into state[]. |
+ state[0] += a(0); |
+ state[1] += b(0); |
+ state[2] += c(0); |
+ state[3] += d(0); |
+ state[4] += e(0); |
+ state[5] += f(0); |
+ state[6] += g(0); |
+ state[7] += h(0); |
+} |
+ |
+ |
+static void |
+process(lzma_check_state *check) |
+{ |
+#ifdef WORDS_BIGENDIAN |
+ transform(check->state.sha256.state, check->buffer.u32); |
+ |
+#else |
+ uint32_t data[16]; |
+ |
+ for (size_t i = 0; i < 16; ++i) |
+ data[i] = bswap32(check->buffer.u32[i]); |
+ |
+ transform(check->state.sha256.state, data); |
+#endif |
+ |
+ return; |
+} |
+ |
+ |
+extern void |
+lzma_sha256_init(lzma_check_state *check) |
+{ |
+ static const uint32_t s[8] = { |
+ 0x6A09E667, 0xBB67AE85, 0x3C6EF372, 0xA54FF53A, |
+ 0x510E527F, 0x9B05688C, 0x1F83D9AB, 0x5BE0CD19, |
+ }; |
+ |
+ memcpy(check->state.sha256.state, s, sizeof(s)); |
+ check->state.sha256.size = 0; |
+ |
+ return; |
+} |
+ |
+ |
+extern void |
+lzma_sha256_update(const uint8_t *buf, size_t size, lzma_check_state *check) |
+{ |
+ // Copy the input data into a properly aligned temporary buffer. |
+ // This way we can be called with arbitrarily sized buffers |
+ // (no need to be multiple of 64 bytes), and the code works also |
+ // on architectures that don't allow unaligned memory access. |
+ while (size > 0) { |
+ const size_t copy_start = check->state.sha256.size & 0x3F; |
+ size_t copy_size = 64 - copy_start; |
+ if (copy_size > size) |
+ copy_size = size; |
+ |
+ memcpy(check->buffer.u8 + copy_start, buf, copy_size); |
+ |
+ buf += copy_size; |
+ size -= copy_size; |
+ check->state.sha256.size += copy_size; |
+ |
+ if ((check->state.sha256.size & 0x3F) == 0) |
+ process(check); |
+ } |
+ |
+ return; |
+} |
+ |
+ |
+extern void |
+lzma_sha256_finish(lzma_check_state *check) |
+{ |
+ // Add padding as described in RFC 3174 (it describes SHA-1 but |
+ // the same padding style is used for SHA-256 too). |
+ size_t pos = check->state.sha256.size & 0x3F; |
+ check->buffer.u8[pos++] = 0x80; |
+ |
+ while (pos != 64 - 8) { |
+ if (pos == 64) { |
+ process(check); |
+ pos = 0; |
+ } |
+ |
+ check->buffer.u8[pos++] = 0x00; |
+ } |
+ |
+ // Convert the message size from bytes to bits. |
+ check->state.sha256.size *= 8; |
+ |
+ check->buffer.u64[(64 - 8) / 8] = conv64be(check->state.sha256.size); |
+ |
+ process(check); |
+ |
+ for (size_t i = 0; i < 8; ++i) |
+ check->buffer.u32[i] = conv32be(check->state.sha256.state[i]); |
+ |
+ return; |
+} |
Property changes on: xz/src/liblzma/check/sha256.c |
___________________________________________________________________ |
Added: svn:eol-style |
+ LF |