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Commit 8bc998f4 by Edward Thomson
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sha1: remove generic implementation 

Remove the "generic" implementation; it should never be used; it only
existed for a no-dependencies configuration, and our bundled sha1dc
satisfies that requirement _and_ is correct.
parent fb6d0181
Showing with 4 additions and 327 deletions
CMakeLists.txt
......@@ -29,7 +29,7 @@ option(USE_NSEC "Support nanosecond precision file mtimes and cti
# Backend selection
option(USE_SSH "Link with libssh2 to enable SSH support" OFF)
option(USE_HTTPS "Enable HTTPS support. Can be set to a specific backend" ON)
option(USE_SHA1 "Enable SHA1. Can be set to CollisionDetection(ON)/HTTPS/Generic" ON)
option(USE_SHA1 "Enable SHA1. Can be set to CollisionDetection(ON)/HTTPS" ON)
option(USE_GSSAPI "Link with libgssapi for SPNEGO auth" OFF)
set(USE_HTTP_PARSER "" CACHE STRING "Specifies the HTTP Parser implementation; either system or builtin.")
set(REGEX_BACKEND "" CACHE STRING "Regular expression implementation. One of regcomp_l, pcre2, pcre, regcomp, or builtin.")
......
cmake/SelectHashes.cmake
......@@ -42,7 +42,7 @@ elseif(USE_SHA1 STREQUAL "mbedTLS")
list(APPEND LIBGIT2_PC_LIBS ${MBEDTLS_LIBRARIES})
elseif(USE_SHA1 STREQUAL "Win32")
set(GIT_SHA1_WIN32 1)
elseif(NOT (USE_SHA1 STREQUAL "Generic"))
else()
message(FATAL_ERROR "Asked for unknown SHA1 backend: ${USE_SHA1}")
endif()
......
src/util/CMakeLists.txt
......@@ -41,8 +41,6 @@ elseif(USE_SHA1 STREQUAL "mbedTLS")
file(GLOB UTIL_SRC_HASH hash/sha1/mbedtls.*)
elseif(USE_SHA1 STREQUAL "Win32")
file(GLOB UTIL_SRC_HASH hash/sha1/win32.*)
elseif(USE_SHA1 STREQUAL "Generic")
file(GLOB UTIL_SRC_HASH hash/sha1/generic.*)
else()
message(FATAL_ERROR "Asked for unknown SHA1 backend: ${USE_SHA1}")
endif()
......
src/util/hash/sha1.h
......@@ -12,9 +12,7 @@
typedef struct git_hash_sha1_ctx git_hash_sha1_ctx;
#if defined(GIT_SHA1_COLLISIONDETECT)
# include "sha1/collisiondetect.h"
#elif defined(GIT_SHA1_COMMON_CRYPTO)
#if defined(GIT_SHA1_COMMON_CRYPTO)
# include "sha1/common_crypto.h"
#elif defined(GIT_SHA1_OPENSSL)
# include "sha1/openssl.h"
......@@ -23,7 +21,7 @@ typedef struct git_hash_sha1_ctx git_hash_sha1_ctx;
#elif defined(GIT_SHA1_MBEDTLS)
# include "sha1/mbedtls.h"
#else
# include "sha1/generic.h"
# include "sha1/collisiondetect.h"
#endif
#define GIT_HASH_SHA1_SIZE 20
......
src/util/hash/sha1/generic.c deleted 100644 → 0
/*
* Copyright (C) the libgit2 contributors. All rights reserved.
*
* This file is part of libgit2, distributed under the GNU GPL v2 with
* a Linking Exception. For full terms see the included COPYING file.
*/
#include "generic.h"
#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
/*
* Force usage of rol or ror by selecting the one with the smaller constant.
* It _can_ generate slightly smaller code (a constant of 1 is special), but
* perhaps more importantly it's possibly faster on any uarch that does a
* rotate with a loop.
*/
#define SHA_ASM(op, x, n) (__extension__ ({ unsigned int __res; __asm__(op " %1,%0":"=r" (__res):"i" (n), "0" (x)); __res; }))
#define SHA_ROL(x,n) SHA_ASM("rol", x, n)
#define SHA_ROR(x,n) SHA_ASM("ror", x, n)
#else
#define SHA_ROT(X,l,r) (((X) << (l)) | ((X) >> (r)))
#define SHA_ROL(X,n) SHA_ROT(X,n,32-(n))
#define SHA_ROR(X,n) SHA_ROT(X,32-(n),n)
#endif
/*
* If you have 32 registers or more, the compiler can (and should)
* try to change the array[] accesses into registers. However, on
* machines with less than ~25 registers, that won't really work,
* and at least gcc will make an unholy mess of it.
*
* So to avoid that mess which just slows things down, we force
* the stores to memory to actually happen (we might be better off
* with a 'W(t)=(val);asm("":"+m" (W(t))' there instead, as
* suggested by Artur Skawina - that will also make gcc unable to
* try to do the silly "optimize away loads" part because it won't
* see what the value will be).
*
* Ben Herrenschmidt reports that on PPC, the C version comes close
* to the optimized asm with this (ie on PPC you don't want that
* 'volatile', since there are lots of registers).
*
* On ARM we get the best code generation by forcing a full memory barrier
* between each SHA_ROUND, otherwise gcc happily get wild with spilling and
* the stack frame size simply explode and performance goes down the drain.
*/
#if defined(__i386__) || defined(__x86_64__)
#define setW(x, val) (*(volatile unsigned int *)&W(x) = (val))
#elif defined(__GNUC__) && defined(__arm__)
#define setW(x, val) do { W(x) = (val); __asm__("":::"memory"); } while (0)
#else
#define setW(x, val) (W(x) = (val))
#endif
/*
* Performance might be improved if the CPU architecture is OK with
* unaligned 32-bit loads and a fast ntohl() is available.
* Otherwise fall back to byte loads and shifts which is portable,
* and is faster on architectures with memory alignment issues.
*/
#if defined(__i386__) || defined(__x86_64__) || \
defined(_M_IX86) || defined(_M_X64) || \
defined(__ppc__) || defined(__ppc64__) || \
defined(__powerpc__) || defined(__powerpc64__) || \
defined(__s390__) || defined(__s390x__)
#define get_be32(p) ntohl(*(const unsigned int *)(p))
#define put_be32(p, v) do { *(unsigned int *)(p) = htonl(v); } while (0)
#else
#define get_be32(p) ( \
(*((const unsigned char *)(p) + 0) << 24) | \
(*((const unsigned char *)(p) + 1) << 16) | \
(*((const unsigned char *)(p) + 2) << 8) | \
(*((const unsigned char *)(p) + 3) << 0) )
#define put_be32(p, v) do { \
unsigned int __v = (v); \
*((unsigned char *)(p) + 0) = __v >> 24; \
*((unsigned char *)(p) + 1) = __v >> 16; \
*((unsigned char *)(p) + 2) = __v >> 8; \
*((unsigned char *)(p) + 3) = __v >> 0; } while (0)
#endif
/* This "rolls" over the 512-bit array */
#define W(x) (array[(x)&15])
/*
* Where do we get the source from? The first 16 iterations get it from
* the input data, the next mix it from the 512-bit array.
*/
#define SHA_SRC(t) get_be32(data + t)
#define SHA_MIX(t) SHA_ROL(W(t+13) ^ W(t+8) ^ W(t+2) ^ W(t), 1)
#define SHA_ROUND(t, input, fn, constant, A, B, C, D, E) do { \
unsigned int TEMP = input(t); setW(t, TEMP); \
E += TEMP + SHA_ROL(A,5) + (fn) + (constant); \
B = SHA_ROR(B, 2); } while (0)
#define T_0_15(t, A, B, C, D, E) SHA_ROUND(t, SHA_SRC, (((C^D)&B)^D) , 0x5a827999, A, B, C, D, E )
#define T_16_19(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, (((C^D)&B)^D) , 0x5a827999, A, B, C, D, E )
#define T_20_39(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, (B^C^D) , 0x6ed9eba1, A, B, C, D, E )
#define T_40_59(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, ((B&C)+(D&(B^C))) , 0x8f1bbcdc, A, B, C, D, E )
#define T_60_79(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, (B^C^D) , 0xca62c1d6, A, B, C, D, E )
static void hash__block(git_hash_sha1_ctx *ctx, const unsigned int *data)
{
unsigned int A,B,C,D,E;
unsigned int array[16];
A = ctx->H[0];
B = ctx->H[1];
C = ctx->H[2];
D = ctx->H[3];
E = ctx->H[4];
/* Round 1 - iterations 0-16 take their input from 'data' */
T_0_15( 0, A, B, C, D, E);
T_0_15( 1, E, A, B, C, D);
T_0_15( 2, D, E, A, B, C);
T_0_15( 3, C, D, E, A, B);
T_0_15( 4, B, C, D, E, A);
T_0_15( 5, A, B, C, D, E);
T_0_15( 6, E, A, B, C, D);
T_0_15( 7, D, E, A, B, C);
T_0_15( 8, C, D, E, A, B);
T_0_15( 9, B, C, D, E, A);
T_0_15(10, A, B, C, D, E);
T_0_15(11, E, A, B, C, D);
T_0_15(12, D, E, A, B, C);
T_0_15(13, C, D, E, A, B);
T_0_15(14, B, C, D, E, A);
T_0_15(15, A, B, C, D, E);
/* Round 1 - tail. Input from 512-bit mixing array */
T_16_19(16, E, A, B, C, D);
T_16_19(17, D, E, A, B, C);
T_16_19(18, C, D, E, A, B);
T_16_19(19, B, C, D, E, A);
/* Round 2 */
T_20_39(20, A, B, C, D, E);
T_20_39(21, E, A, B, C, D);
T_20_39(22, D, E, A, B, C);
T_20_39(23, C, D, E, A, B);
T_20_39(24, B, C, D, E, A);
T_20_39(25, A, B, C, D, E);
T_20_39(26, E, A, B, C, D);
T_20_39(27, D, E, A, B, C);
T_20_39(28, C, D, E, A, B);
T_20_39(29, B, C, D, E, A);
T_20_39(30, A, B, C, D, E);
T_20_39(31, E, A, B, C, D);
T_20_39(32, D, E, A, B, C);
T_20_39(33, C, D, E, A, B);
T_20_39(34, B, C, D, E, A);
T_20_39(35, A, B, C, D, E);
T_20_39(36, E, A, B, C, D);
T_20_39(37, D, E, A, B, C);
T_20_39(38, C, D, E, A, B);
T_20_39(39, B, C, D, E, A);
/* Round 3 */
T_40_59(40, A, B, C, D, E);
T_40_59(41, E, A, B, C, D);
T_40_59(42, D, E, A, B, C);
T_40_59(43, C, D, E, A, B);
T_40_59(44, B, C, D, E, A);
T_40_59(45, A, B, C, D, E);
T_40_59(46, E, A, B, C, D);
T_40_59(47, D, E, A, B, C);
T_40_59(48, C, D, E, A, B);
T_40_59(49, B, C, D, E, A);
T_40_59(50, A, B, C, D, E);
T_40_59(51, E, A, B, C, D);
T_40_59(52, D, E, A, B, C);
T_40_59(53, C, D, E, A, B);
T_40_59(54, B, C, D, E, A);
T_40_59(55, A, B, C, D, E);
T_40_59(56, E, A, B, C, D);
T_40_59(57, D, E, A, B, C);
T_40_59(58, C, D, E, A, B);
T_40_59(59, B, C, D, E, A);
/* Round 4 */
T_60_79(60, A, B, C, D, E);
T_60_79(61, E, A, B, C, D);
T_60_79(62, D, E, A, B, C);
T_60_79(63, C, D, E, A, B);
T_60_79(64, B, C, D, E, A);
T_60_79(65, A, B, C, D, E);
T_60_79(66, E, A, B, C, D);
T_60_79(67, D, E, A, B, C);
T_60_79(68, C, D, E, A, B);
T_60_79(69, B, C, D, E, A);
T_60_79(70, A, B, C, D, E);
T_60_79(71, E, A, B, C, D);
T_60_79(72, D, E, A, B, C);
T_60_79(73, C, D, E, A, B);
T_60_79(74, B, C, D, E, A);
T_60_79(75, A, B, C, D, E);
T_60_79(76, E, A, B, C, D);
T_60_79(77, D, E, A, B, C);
T_60_79(78, C, D, E, A, B);
T_60_79(79, B, C, D, E, A);
ctx->H[0] += A;
ctx->H[1] += B;
ctx->H[2] += C;
ctx->H[3] += D;
ctx->H[4] += E;
}
int git_hash_sha1_global_init(void)
{
return 0;
}
int git_hash_sha1_ctx_init(git_hash_sha1_ctx *ctx)
{
return git_hash_sha1_init(ctx);
}
void git_hash_sha1_ctx_cleanup(git_hash_sha1_ctx *ctx)
{
GIT_UNUSED(ctx);
}
int git_hash_sha1_init(git_hash_sha1_ctx *ctx)
{
ctx->size = 0;
/* Initialize H with the magic constants (see FIPS180 for constants) */
ctx->H[0] = 0x67452301;
ctx->H[1] = 0xefcdab89;
ctx->H[2] = 0x98badcfe;
ctx->H[3] = 0x10325476;
ctx->H[4] = 0xc3d2e1f0;
return 0;
}
int git_hash_sha1_update(git_hash_sha1_ctx *ctx, const void *data, size_t len)
{
unsigned int lenW = ctx->size & 63;
ctx->size += len;
/* Read the data into W and process blocks as they get full */
if (lenW) {
unsigned int left = 64 - lenW;
if (len < left)
left = (unsigned int)len;
memcpy(lenW + (char *)ctx->W, data, left);
lenW = (lenW + left) & 63;
len -= left;
data = ((const char *)data + left);
if (lenW)
return 0;
hash__block(ctx, ctx->W);
}
while (len >= 64) {
hash__block(ctx, data);
data = ((const char *)data + 64);
len -= 64;
}
if (len)
memcpy(ctx->W, data, len);
return 0;
}
int git_hash_sha1_final(unsigned char *out, git_hash_sha1_ctx *ctx)
{
static const unsigned char pad[64] = { 0x80 };
unsigned int padlen[2];
int i;
/* Pad with a binary 1 (ie 0x80), then zeroes, then length */
padlen[0] = htonl((uint32_t)(ctx->size >> 29));
padlen[1] = htonl((uint32_t)(ctx->size << 3));
i = ctx->size & 63;
git_hash_sha1_update(ctx, pad, 1+ (63 & (55 - i)));
git_hash_sha1_update(ctx, padlen, 8);
/* Output hash */
for (i = 0; i < 5; i++)
put_be32(out + i*4, ctx->H[i]);
return 0;
}
src/util/hash/sha1/generic.h deleted 100644 → 0
/*
* Copyright (C) the libgit2 contributors. All rights reserved.
*
* This file is part of libgit2, distributed under the GNU GPL v2 with
* a Linking Exception. For full terms see the included COPYING file.
*/
#ifndef INCLUDE_hash_sha1_generic_h__
#define INCLUDE_hash_sha1_generic_h__
#include "hash/sha1.h"
struct git_hash_sha1_ctx {
uint64_t size;
unsigned int H[5];
unsigned int W[16];
};
#endif
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