commit cae72e5d9fade85faa1c25ae63f324b266ed2789 Author: Zack Weinberg zackw@panix.com Date: Fri Jul 8 16:33:14 2011 -0700

Switch to building sha256.c separately with an automake conditional. Not tested on a platform that *needs* sha256.c yet. --- Makefile.am | 6 +++- configure.ac | 6 ++++ src/crypt.c | 17 +---------- src/sha256.c | 88 +++++++++++++++------------------------------------------ src/sha256.h | 18 ++++++++++++ 5 files changed, 53 insertions(+), 82 deletions(-)

diff --git a/Makefile.am b/Makefile.am index 096c0fa..a78d7d0 100644 --- a/Makefile.am +++ b/Makefile.am @@ -15,6 +15,9 @@ libobfsproxy_a_SOURCES = \ src/util.c \ src/protocols/dummy.c \ src/protocols/obfs2.c +if NEED_SHA256 +libobfsproxy_a_SOURCES += src/sha256.c +endif

obfsproxy_SOURCES = \ src/main.c @@ -30,6 +33,7 @@ noinst_HEADERS = \ src/crypt.h \ src/network.h \ src/protocol.h \ + src/sha256.h \ src/socks.h \ src/util.h \ src/protocols/dummy.h \ @@ -37,6 +41,6 @@ noinst_HEADERS = \ src/test/tinytest.h \ src/test/tinytest_macros.h

-EXTRA_DIST = doc/protocol-spec.txt src/sha256.c +EXTRA_DIST = doc/protocol-spec.txt

TESTS = unittests diff --git a/configure.ac b/configure.ac index e49ddf3..7465708 100644 --- a/configure.ac +++ b/configure.ac @@ -25,6 +25,12 @@ AS_IF([test "x$ac_cv_lib_winsock" = xyes], [ws32_LIBS=]) AC_SUBST(ws32_LIBS)

+save_LIBS="$LIBS" +LIBS="$openssl_LIBS" +AC_CHECK_FUNC(SHA256_Init, [:], [:]) +LIBS="$save_LIBS" +AM_CONDITIONAL(NEED_SHA256, [test x$ac_cv_func_SHA256_Init = xno]) + AC_CONFIG_FILES([Makefile]) AC_CONFIG_HEADERS([config.h]) AC_OUTPUT diff --git a/src/crypt.c b/src/crypt.c index 6c35f10..91868f2 100644 --- a/src/crypt.c +++ b/src/crypt.c @@ -24,22 +24,7 @@ #define USE_OPENSSL_SHA256 1 #include <openssl/sha.h> #else -#define STMT_BEGIN do { -#define STMT_END } while (0) -static void -set_uint32(void *ptr, uint32_t val) -{ - memcpy(ptr, &val, 4); -} -static uint32_t -get_uint32(const void *ptr) -{ - uint32_t val; - memcpy(&val, ptr, 4); - return val; -} -#define LTC_ARGCHK(x) assert((x)) -#include "../sha256.c" +#include "sha256.h" #endif

int diff --git a/src/sha256.c b/src/sha256.c index d28dcce..4833b99 100644 --- a/src/sha256.c +++ b/src/sha256.c @@ -4,12 +4,25 @@ LibTomCrypt, version 1.6. Tor uses it on platforms where OpenSSL doesn't have a SHA256. */

- -typedef struct sha256_state { - uint64_t length; - uint32_t state[8], curlen; - unsigned char buf[64]; -} sha256_state; +#include "sha256.h" +#include <assert.h> +#include <string.h> + +#define STMT_BEGIN do { +#define STMT_END } while (0) +static void +set_uint32(void *ptr, uint32_t val) +{ + memcpy(ptr, &val, 4); +} +static uint32_t +get_uint32(const void *ptr) +{ + uint32_t val; + memcpy(&val, ptr, 4); + return val; +} +#define LTC_ARGCHK(x) assert((x))

#define CRYPT_OK 0 #define CRYPT_NOP -1 @@ -43,26 +56,6 @@ typedef struct sha256_state { SHA256 by Tom St Denis */

- -#ifdef LTC_SMALL_CODE -/* the K array */ -static const uint32_t K[64] = { - 0x428a2f98UL, 0x71374491UL, 0xb5c0fbcfUL, 0xe9b5dba5UL, 0x3956c25bUL, - 0x59f111f1UL, 0x923f82a4UL, 0xab1c5ed5UL, 0xd807aa98UL, 0x12835b01UL, - 0x243185beUL, 0x550c7dc3UL, 0x72be5d74UL, 0x80deb1feUL, 0x9bdc06a7UL, - 0xc19bf174UL, 0xe49b69c1UL, 0xefbe4786UL, 0x0fc19dc6UL, 0x240ca1ccUL, - 0x2de92c6fUL, 0x4a7484aaUL, 0x5cb0a9dcUL, 0x76f988daUL, 0x983e5152UL, - 0xa831c66dUL, 0xb00327c8UL, 0xbf597fc7UL, 0xc6e00bf3UL, 0xd5a79147UL, - 0x06ca6351UL, 0x14292967UL, 0x27b70a85UL, 0x2e1b2138UL, 0x4d2c6dfcUL, - 0x53380d13UL, 0x650a7354UL, 0x766a0abbUL, 0x81c2c92eUL, 0x92722c85UL, - 0xa2bfe8a1UL, 0xa81a664bUL, 0xc24b8b70UL, 0xc76c51a3UL, 0xd192e819UL, - 0xd6990624UL, 0xf40e3585UL, 0x106aa070UL, 0x19a4c116UL, 0x1e376c08UL, - 0x2748774cUL, 0x34b0bcb5UL, 0x391c0cb3UL, 0x4ed8aa4aUL, 0x5b9cca4fUL, - 0x682e6ff3UL, 0x748f82eeUL, 0x78a5636fUL, 0x84c87814UL, 0x8cc70208UL, - 0x90befffaUL, 0xa4506cebUL, 0xbef9a3f7UL, 0xc67178f2UL -}; -#endif - /* Various logical functions */ #define Ch(x,y,z) (z ^ (x & (y ^ z))) #define Maj(x,y,z) (((x | y) & z) | (x & y)) @@ -74,16 +67,9 @@ static const uint32_t K[64] = { #define Gamma1(x) (S(x, 17) ^ S(x, 19) ^ R(x, 10))

/* compress 512-bits */ -#ifdef LTC_CLEAN_STACK -static int _sha256_compress(sha256_state * md, unsigned char *buf) -#else static int sha256_compress(sha256_state * md, unsigned char *buf) -#endif { uint32_t S[8], W[64], t0, t1; -#ifdef LTC_SMALL_CODE - uint32_t t; -#endif int i;

/* copy state into S */ @@ -102,19 +88,6 @@ static int sha256_compress(sha256_state * md, unsigned char *buf) }

/* Compress */ -#ifdef LTC_SMALL_CODE -#define RND(a,b,c,d,e,f,g,h,i) \ - t0 = h + Sigma1(e) + Ch(e, f, g) + K[i] + W[i]; \ - t1 = Sigma0(a) + Maj(a, b, c); \ - d += t0; \ - h = t0 + t1; - - for (i = 0; i < 64; ++i) { - RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],i); - t = S[7]; S[7] = S[6]; S[6] = S[5]; S[5] = S[4]; - S[4] = S[3]; S[3] = S[2]; S[2] = S[1]; S[1] = S[0]; S[0] = t; - } -#else #define RND(a,b,c,d,e,f,g,h,i,ki) \ t0 = h + Sigma1(e) + Ch(e, f, g) + ki + W[i]; \ t1 = Sigma0(a) + Maj(a, b, c); \ @@ -188,8 +161,6 @@ static int sha256_compress(sha256_state * md, unsigned char *buf)

#undef RND

-#endif - /* feedback */ for (i = 0; i < 8; i++) { md->state[i] = md->state[i] + S[i]; @@ -197,22 +168,12 @@ static int sha256_compress(sha256_state * md, unsigned char *buf) return CRYPT_OK; }

-#ifdef LTC_CLEAN_STACK -static int sha256_compress(sha256_state * md, unsigned char *buf) -{ - int err; - err = _sha256_compress(md, buf); - burn_stack(sizeof(uint32_t) * 74); - return err; -} -#endif - /** Initialize the hash state @param md The hash state you wish to initialize @return CRYPT_OK if successful */ -static int sha256_init(sha256_state * md) +int sha256_init(sha256_state * md) { LTC_ARGCHK(md != NULL);

@@ -236,7 +197,8 @@ static int sha256_init(sha256_state * md) @param inlen The length of the data (octets) @return CRYPT_OK if successful */ -static int sha256_process (sha256_state * md, const unsigned char *in, unsigned long inlen) +int sha256_process (sha256_state * md, const unsigned char *in, + unsigned long inlen) { unsigned long n; int err; @@ -277,7 +239,7 @@ static int sha256_process (sha256_state * md, const unsigned char *in, unsigned @param out [out] The destination of the hash (32 bytes) @return CRYPT_OK if successful */ -static int sha256_done(sha256_state * md, unsigned char *out) +int sha256_done(sha256_state * md, unsigned char *out) { int i;

@@ -288,7 +250,6 @@ static int sha256_done(sha256_state * md, unsigned char *out) return CRYPT_INVALID_ARG; }

- /* increase the length of the message */ md->length += md->curlen * 8;

@@ -320,9 +281,6 @@ static int sha256_done(sha256_state * md, unsigned char *out) for (i = 0; i < 8; i++) { STORE32H(md->state[i], out+(4*i)); } -#ifdef LTC_CLEAN_STACK - zeromem(md, sizeof(sha256_state)); -#endif return CRYPT_OK; }

diff --git a/src/sha256.h b/src/sha256.h new file mode 100644 index 0000000..b6a75be --- /dev/null +++ b/src/sha256.h @@ -0,0 +1,18 @@ +/* Header file for the fallback (libtomcrypt) implementation of SHA256. */ +#ifndef SHA256_H +#define SHA256_H + +#include <stdint.h> + +typedef struct sha256_state { + uint64_t length; + uint32_t state[8], curlen; + unsigned char buf[64]; +} sha256_state; + +int sha256_init(sha256_state * md); +int sha256_process(sha256_state * md, const unsigned char *in, + unsigned long inlen); +int sha256_done(sha256_state * md, unsigned char *out); + +#endif