commit 814eba4586ee932e896c6de230592882c49b0f9c Author: Tomás Touceda chiiph@torproject.org Date: Wed Jul 4 21:09:09 2012 -0300

Add hmac_sha256 implementation based on tor's implementation --- src/common/crypto.cpp | 87 +++++++++++++ src/common/crypto.h | 7 + src/common/sha256.c | 331 +++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 425 insertions(+), 0 deletions(-)

diff --git a/src/common/crypto.cpp b/src/common/crypto.cpp index 223d202..5ae5295 100644 --- a/src/common/crypto.cpp +++ b/src/common/crypto.cpp @@ -187,3 +187,90 @@ crypto_secret_to_key(const QString &secret, const QByteArray &salt, quint8 c) return hash.result(); }

+/** + * Read a 32-bit value beginning at <b>cp</b>. Equivalent to + * *(uint32_t*)(cp), but will not cause segfaults on platforms that forbid + * unaligned memory access. + */ +uint32_t +get_uint32(const void *cp) +{ + uint32_t v; + memcpy(&v,cp,4); + return v; +} +/** + * Set a 32-bit value beginning at <b>cp</b> to <b>v</b>. Equivalent to + * *(uint32_t*)(cp) = v, but will not cause segfaults on platforms that forbid + * unaligned memory access. */ +void +set_uint32(void *cp, uint32_t v) +{ + memcpy(cp,&v,4); +} + +#define STMT_BEGIN do { +#define STMT_END } while(0) +#define SHA256_CTX sha256_state +#define SHA256_Init sha256_init +#define SHA256_Update sha256_process +#define LTC_ARGCHK(x) Q_ASSERT(x) +#include "sha256.c" +#define SHA256_Final(a,b) sha256_done(b,a) + +static unsigned char * +SHA256(const unsigned char *m, size_t len, unsigned char *d) +{ + SHA256_CTX ctx; + SHA256_Init(&ctx); + SHA256_Update(&ctx, m, len); + SHA256_Final(d, &ctx); + return d; +} + +/** Compute the HMAC-SHA-256 of the <b>msg_len</b> bytes in <b>msg</b>, using + * the <b>key</b> of length <b>key_len</b>. Store the DIGEST256_LEN-byte + * result in <b>hmac_out</b>. + */ +void +crypto_hmac_sha256(char *hmac_out, + const char *key, size_t key_len, + const char *msg, size_t msg_len) +{ +#define BLOCKSIZE 64 +#define DIGESTSIZE 32 + uint8_t k[BLOCKSIZE]; + uint8_t pad[BLOCKSIZE]; + uint8_t d[DIGESTSIZE]; + int i; + SHA256_CTX st; + + if (key_len <= BLOCKSIZE) { + memset(k, 0, sizeof(k)); + memcpy(k, key, key_len); /* not time invariant in key_len */ + } else { + SHA256((const uint8_t *)key, key_len, k); + memset(k+DIGESTSIZE, 0, sizeof(k)-DIGESTSIZE); + } + for (i = 0; i < BLOCKSIZE; ++i) + pad[i] = k[i] ^ 0x36; + SHA256_Init(&st); + SHA256_Update(&st, pad, BLOCKSIZE); + SHA256_Update(&st, (uint8_t*)msg, msg_len); + SHA256_Final(d, &st); + + for (i = 0; i < BLOCKSIZE; ++i) + pad[i] = k[i] ^ 0x5c; + SHA256_Init(&st); + SHA256_Update(&st, pad, BLOCKSIZE); + SHA256_Update(&st, d, DIGESTSIZE); + SHA256_Final((uint8_t*)hmac_out, &st); + + /* Now clear everything. */ + memset(k, 0, sizeof(k)); + memset(pad, 0, sizeof(pad)); + memset(d, 0, sizeof(d)); + memset(&st, 0, sizeof(st)); +#undef BLOCKSIZE +#undef DIGESTSIZE +} diff --git a/src/common/crypto.h b/src/common/crypto.h index 65582ed..cbfde62 100644 --- a/src/common/crypto.h +++ b/src/common/crypto.h @@ -73,6 +73,13 @@ QString crypto_rand_string(int len); * return a default-constructed QByteArray. */ QByteArray crypto_secret_to_key(const QString &secret, const QByteArray &salt, quint8 c); +/** Compute the HMAC-SHA-256 of the <b>msg_len</b> bytes in <b>msg</b>, using + * the <b>key</b> of length <b>key_len</b>. Store the DIGEST256_LEN-byte + * result in <b>hmac_out</b>. + */ +void +crypto_hmac_sha256(char *hmac_out, const char *key, size_t key_len, + const char *msg, size_t msg_len);

#endif

diff --git a/src/common/sha256.c b/src/common/sha256.c new file mode 100644 index 0000000..813c68d --- /dev/null +++ b/src/common/sha256.c @@ -0,0 +1,331 @@ +/* Copyright (c) 2009-2012, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ +/* This SHA256 implementation is adapted from the public domain one in + 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; + +#define CRYPT_OK 0 +#define CRYPT_NOP -1 +#define CRYPT_INVALID_ARG -2 + +#define LOAD32H(x,y) STMT_BEGIN x = ntohl(get_uint32((const char*)y)); STMT_END +#define STORE32H(x,y) STMT_BEGIN set_uint32((char*)y, htonl(x)); STMT_END +#define STORE64H(x,y) STMT_BEGIN \ + set_uint32((char*)y, htonl((uint32_t)((x)>>32))); \ + set_uint32(((char*)y)+4, htonl((uint32_t)((x)&0xffffffff))); \ + STMT_END +#define RORc(x, y) ( ((((unsigned long)(x)&0xFFFFFFFFUL)>>(unsigned long)((y)&31)) | ((unsigned long)(x)<<(unsigned long)(32-((y)&31)))) & 0xFFFFFFFFUL) +#ifndef MIN + #define MIN(x, y) ( ((x)<(y))?(x):(y) ) +#endif + + +/* LibTomCrypt, modular cryptographic library -- Tom St Denis + * + * LibTomCrypt is a library that provides various cryptographic + * algorithms in a highly modular and flexible manner. + * + * The library is free for all purposes without any express + * guarantee it works. + * + * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com + */ + +/** + @file sha256.c + 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)) +#define S(x, n) RORc((x),(n)) +#define R(x, n) (((x)&0xFFFFFFFFUL)>>(n)) +#define Sigma0(x) (S(x, 2) ^ S(x, 13) ^ S(x, 22)) +#define Sigma1(x) (S(x, 6) ^ S(x, 11) ^ S(x, 25)) +#define Gamma0(x) (S(x, 7) ^ S(x, 18) ^ R(x, 3)) +#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 */ + for (i = 0; i < 8; i++) { + S[i] = md->state[i]; + } + + /* copy the state into 512-bits into W[0..15] */ + for (i = 0; i < 16; i++) { + LOAD32H(W[i], buf + (4*i)); + } + + /* fill W[16..63] */ + for (i = 16; i < 64; i++) { + W[i] = Gamma1(W[i - 2]) + W[i - 7] + Gamma0(W[i - 15]) + W[i - 16]; + } + + /* 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); \ + d += t0; \ + h = t0 + t1; + + RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],0,0x428a2f98); + RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],1,0x71374491); + RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],2,0xb5c0fbcf); + RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],3,0xe9b5dba5); + RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],4,0x3956c25b); + RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],5,0x59f111f1); + RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],6,0x923f82a4); + RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],7,0xab1c5ed5); + RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],8,0xd807aa98); + RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],9,0x12835b01); + RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],10,0x243185be); + RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],11,0x550c7dc3); + RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],12,0x72be5d74); + RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],13,0x80deb1fe); + RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],14,0x9bdc06a7); + RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],15,0xc19bf174); + RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],16,0xe49b69c1); + RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],17,0xefbe4786); + RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],18,0x0fc19dc6); + RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],19,0x240ca1cc); + RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],20,0x2de92c6f); + RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],21,0x4a7484aa); + RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],22,0x5cb0a9dc); + RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],23,0x76f988da); + RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],24,0x983e5152); + RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],25,0xa831c66d); + RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],26,0xb00327c8); + RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],27,0xbf597fc7); + RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],28,0xc6e00bf3); + RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],29,0xd5a79147); + RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],30,0x06ca6351); + RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],31,0x14292967); + RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],32,0x27b70a85); + RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],33,0x2e1b2138); + RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],34,0x4d2c6dfc); + RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],35,0x53380d13); + RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],36,0x650a7354); + RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],37,0x766a0abb); + RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],38,0x81c2c92e); + RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],39,0x92722c85); + RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],40,0xa2bfe8a1); + RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],41,0xa81a664b); + RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],42,0xc24b8b70); + RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],43,0xc76c51a3); + RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],44,0xd192e819); + RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],45,0xd6990624); + RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],46,0xf40e3585); + RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],47,0x106aa070); + RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],48,0x19a4c116); + RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],49,0x1e376c08); + RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],50,0x2748774c); + RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],51,0x34b0bcb5); + RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],52,0x391c0cb3); + RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],53,0x4ed8aa4a); + RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],54,0x5b9cca4f); + RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],55,0x682e6ff3); + RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],56,0x748f82ee); + RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],57,0x78a5636f); + RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],58,0x84c87814); + RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],59,0x8cc70208); + RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],60,0x90befffa); + RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],61,0xa4506ceb); + RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],62,0xbef9a3f7); + RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],63,0xc67178f2); + +#undef RND + +#endif + + /* feedback */ + for (i = 0; i < 8; i++) { + md->state[i] = md->state[i] + S[i]; + } + 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) +{ + LTC_ARGCHK(md != NULL); + + md->curlen = 0; + md->length = 0; + md->state[0] = 0x6A09E667UL; + md->state[1] = 0xBB67AE85UL; + md->state[2] = 0x3C6EF372UL; + md->state[3] = 0xA54FF53AUL; + md->state[4] = 0x510E527FUL; + md->state[5] = 0x9B05688CUL; + md->state[6] = 0x1F83D9ABUL; + md->state[7] = 0x5BE0CD19UL; + return CRYPT_OK; +} + +/** + Process a block of memory though the hash + @param md The hash state + @param in The data to hash + @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) +{ + unsigned long n; + int err; + LTC_ARGCHK(md != NULL); + LTC_ARGCHK(in != NULL); + if (md->curlen > sizeof(md->buf)) { + return CRYPT_INVALID_ARG; + } + while (inlen > 0) { + if (md->curlen == 0 && inlen >= 64) { + if ((err = sha256_compress (md, (unsigned char *)in)) != CRYPT_OK) { + return err; + } + md->length += 64 * 8; + in += 64; + inlen -= 64; + } else { + n = MIN(inlen, (64 - md->curlen)); + memcpy(md->buf + md->curlen, in, (size_t)n); + md->curlen += n; + in += n; + inlen -= n; + if (md->curlen == 64) { + if ((err = sha256_compress (md, md->buf)) != CRYPT_OK) { + return err; + } + md->length += 8*64; + md->curlen = 0; + } + } + } + return CRYPT_OK; +} + +/** + Terminate the hash to get the digest + @param md The hash state + @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 i; + + LTC_ARGCHK(md != NULL); + LTC_ARGCHK(out != NULL); + + if (md->curlen >= sizeof(md->buf)) { + return CRYPT_INVALID_ARG; + } + + + /* increase the length of the message */ + md->length += md->curlen * 8; + + /* append the '1' bit */ + md->buf[md->curlen++] = (unsigned char)0x80; + + /* if the length is currently above 56 bytes we append zeros + * then compress. Then we can fall back to padding zeros and length + * encoding like normal. + */ + if (md->curlen > 56) { + while (md->curlen < 64) { + md->buf[md->curlen++] = (unsigned char)0; + } + sha256_compress(md, md->buf); + md->curlen = 0; + } + + /* pad upto 56 bytes of zeroes */ + while (md->curlen < 56) { + md->buf[md->curlen++] = (unsigned char)0; + } + + /* store length */ + STORE64H(md->length, md->buf+56); + sha256_compress(md, md->buf); + + /* copy output */ + 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; +} + +/* $Source: /cvs/libtom/libtomcrypt/src/hashes/sha2/sha256.c,v $ */ +/* $Revision: 1.9 $ */ +/* $Date: 2006/11/01 09:28:17 $ */