diff options
author | Anas Nashif <anas.nashif@intel.com> | 2013-02-22 07:24:03 -0800 |
---|---|---|
committer | Anas Nashif <anas.nashif@intel.com> | 2013-02-22 07:24:03 -0800 |
commit | 2cdd5bf0e73eff343d4ca085b315e78982e76202 (patch) | |
tree | e9082ffa48b4651e998fd9caa1dab827a9e6b7ae /libedsio/sha.c | |
download | xdelta1-upstream.tar.gz xdelta1-upstream.tar.bz2 xdelta1-upstream.zip |
Imported Upstream version 1.1.4upstream/1.1.4upstream
Diffstat (limited to 'libedsio/sha.c')
-rwxr-xr-x | libedsio/sha.c | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/libedsio/sha.c b/libedsio/sha.c new file mode 100755 index 0000000..503fe85 --- /dev/null +++ b/libedsio/sha.c @@ -0,0 +1,239 @@ +/* NIST Secure Hash Algorithm */ +/* heavily modified by Uwe Hollerbach <uh@alumni.caltech edu> */ +/* from Peter C. Gutmann's implementation as found in */ +/* Applied Cryptography by Bruce Schneier */ +/* Further modifications to include the "UNRAVEL" stuff, below */ + +/* This code is in the public domain */ + +#include "edsio.h" +#include <string.h> + +#define SHA_BLOCKSIZE 64 +#define SHA_DIGESTSIZE 20 + +/* UNRAVEL should be fastest & biggest */ +/* UNROLL_LOOPS should be just as big, but slightly slower */ +/* both undefined should be smallest and slowest */ + +#define UNRAVEL +/* #define UNROLL_LOOPS */ + +/* by default, compile for little-endian machines (Intel, Vax) */ +/* change for big-endian machines; for machines which are neither, */ +/* you will need to change the definition of maybe_byte_reverse */ + +#ifndef WORDS_BIGENDIAN /* from config.h */ +#define SHA_LITTLE_ENDIAN +#endif + +/* NIST's proposed modification to SHA of 7/11/94 may be */ +/* activated by defining USE_MODIFIED_SHA; leave it off for now */ +#undef USE_MODIFIED_SHA + +/* SHA f()-functions */ + +#define f1(x,y,z) ((x & y) | (~x & z)) +#define f2(x,y,z) (x ^ y ^ z) +#define f3(x,y,z) ((x & y) | (x & z) | (y & z)) +#define f4(x,y,z) (x ^ y ^ z) + +/* SHA constants */ + +#define CONST1 0x5a827999L +#define CONST2 0x6ed9eba1L +#define CONST3 0x8f1bbcdcL +#define CONST4 0xca62c1d6L + +/* 32-bit rotate */ + +#define ROT32(x,n) ((x << n) | (x >> (32 - n))) + +/* the generic case, for when the overall rotation is not unraveled */ + +#define FG(n) \ + T = ROT32(A,5) + f##n(B,C,D) + E + *WP++ + CONST##n; \ + E = D; D = C; C = ROT32(B,30); B = A; A = T + +/* specific cases, for when the overall rotation is unraveled */ + +#define FA(n) \ + T = ROT32(A,5) + f##n(B,C,D) + E + *WP++ + CONST##n; B = ROT32(B,30) + +#define FB(n) \ + E = ROT32(T,5) + f##n(A,B,C) + D + *WP++ + CONST##n; A = ROT32(A,30) + +#define FC(n) \ + D = ROT32(E,5) + f##n(T,A,B) + C + *WP++ + CONST##n; T = ROT32(T,30) + +#define FD(n) \ + C = ROT32(D,5) + f##n(E,T,A) + B + *WP++ + CONST##n; E = ROT32(E,30) + +#define FE(n) \ + B = ROT32(C,5) + f##n(D,E,T) + A + *WP++ + CONST##n; D = ROT32(D,30) + +#define FT(n) \ + A = ROT32(B,5) + f##n(C,D,E) + T + *WP++ + CONST##n; C = ROT32(C,30) + +/* do SHA transformation */ + +static void sha_transform(EdsioSHACtx *ctx) +{ + int i; + guint32 T, A, B, C, D, E, W[80], *WP; + + for (i = 0; i < 16; ++i) { + W[i] = ctx->data[i]; + } + for (i = 16; i < 80; ++i) { + W[i] = W[i-3] ^ W[i-8] ^ W[i-14] ^ W[i-16]; +#ifdef USE_MODIFIED_SHA + W[i] = ROT32(W[i], 1); +#endif /* USE_MODIFIED_SHA */ + } + A = ctx->digest[0]; + B = ctx->digest[1]; + C = ctx->digest[2]; + D = ctx->digest[3]; + E = ctx->digest[4]; + WP = W; +#ifdef UNRAVEL + FA(1); FB(1); FC(1); FD(1); FE(1); FT(1); FA(1); FB(1); FC(1); FD(1); + FE(1); FT(1); FA(1); FB(1); FC(1); FD(1); FE(1); FT(1); FA(1); FB(1); + FC(2); FD(2); FE(2); FT(2); FA(2); FB(2); FC(2); FD(2); FE(2); FT(2); + FA(2); FB(2); FC(2); FD(2); FE(2); FT(2); FA(2); FB(2); FC(2); FD(2); + FE(3); FT(3); FA(3); FB(3); FC(3); FD(3); FE(3); FT(3); FA(3); FB(3); + FC(3); FD(3); FE(3); FT(3); FA(3); FB(3); FC(3); FD(3); FE(3); FT(3); + FA(4); FB(4); FC(4); FD(4); FE(4); FT(4); FA(4); FB(4); FC(4); FD(4); + FE(4); FT(4); FA(4); FB(4); FC(4); FD(4); FE(4); FT(4); FA(4); FB(4); + ctx->digest[0] += E; + ctx->digest[1] += T; + ctx->digest[2] += A; + ctx->digest[3] += B; + ctx->digest[4] += C; +#else /* !UNRAVEL */ +#ifdef UNROLL_LOOPS + FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); + FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); FG(1); + FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); + FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); FG(2); + FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); + FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); FG(3); + FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); + FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); FG(4); +#else /* !UNROLL_LOOPS */ + for (i = 0; i < 20; ++i) { FG(1); } + for (i = 20; i < 40; ++i) { FG(2); } + for (i = 40; i < 60; ++i) { FG(3); } + for (i = 60; i < 80; ++i) { FG(4); } +#endif /* !UNROLL_LOOPS */ + ctx->digest[0] += A; + ctx->digest[1] += B; + ctx->digest[2] += C; + ctx->digest[3] += D; + ctx->digest[4] += E; +#endif /* !UNRAVEL */ +} + +#ifdef SHA_LITTLE_ENDIAN + +/* change endianness of data */ + +static void maybe_byte_reverse(guint32 *buffer, int count) +{ + int i; + guint32 in; + + count /= sizeof(guint32); + for (i = 0; i < count; ++i) { + in = *buffer; + *buffer++ = ((in << 24) & 0xff000000) | ((in << 8) & 0x00ff0000) | + ((in >> 8) & 0x0000ff00) | ((in >> 24) & 0x000000ff); + } +} + +#else /* !SHA_LITTLE_ENDIAN */ + +#define maybe_byte_reverse(a,b) /* do nothing */ + +#endif /* SHA_LITTLE_ENDIAN */ + +/* initialize the SHA digest */ + +void edsio_sha_init(EdsioSHACtx *ctx) +{ + ctx->digest[0] = 0x67452301L; + ctx->digest[1] = 0xefcdab89L; + ctx->digest[2] = 0x98badcfeL; + ctx->digest[3] = 0x10325476L; + ctx->digest[4] = 0xc3d2e1f0L; + ctx->count_lo = 0L; + ctx->count_hi = 0L; + ctx->local = 0; +} + +/* update the SHA digest */ + +void edsio_sha_update(EdsioSHACtx *ctx, const guint8 *buffer, guint count) +{ + int i; + + if ((ctx->count_lo + ((guint32) count << 3)) < ctx->count_lo) { + ++ctx->count_hi; + } + ctx->count_lo += (guint32) count << 3; + ctx->count_hi += (guint32) count >> 29; + if (ctx->local) { + i = SHA_BLOCKSIZE - ctx->local; + if (i > count) { + i = count; + } + memcpy(((guint8 *) ctx->data) + ctx->local, buffer, i); + count -= i; + buffer += i; + ctx->local += i; + if (ctx->local == SHA_BLOCKSIZE) { + maybe_byte_reverse(ctx->data, SHA_BLOCKSIZE); + sha_transform(ctx); + } else { + return; + } + } + while (count >= SHA_BLOCKSIZE) { + memcpy(ctx->data, buffer, SHA_BLOCKSIZE); + buffer += SHA_BLOCKSIZE; + count -= SHA_BLOCKSIZE; + maybe_byte_reverse(ctx->data, SHA_BLOCKSIZE); + sha_transform(ctx); + } + memcpy(ctx->data, buffer, count); + ctx->local = count; +} + +/* finish computing the SHA digest */ + +void edsio_sha_final(guint8* digest, EdsioSHACtx *ctx) +{ + int count; + guint32 lo_bit_count, hi_bit_count; + + lo_bit_count = ctx->count_lo; + hi_bit_count = ctx->count_hi; + count = (int) ((lo_bit_count >> 3) & 0x3f); + ((guint8 *) ctx->data)[count++] = 0x80; + if (count > SHA_BLOCKSIZE - 8) { + memset(((guint8 *) ctx->data) + count, 0, SHA_BLOCKSIZE - count); + maybe_byte_reverse(ctx->data, SHA_BLOCKSIZE); + sha_transform(ctx); + memset((guint8 *) ctx->data, 0, SHA_BLOCKSIZE - 8); + } else { + memset(((guint8 *) ctx->data) + count, 0, + SHA_BLOCKSIZE - 8 - count); + } + maybe_byte_reverse(ctx->data, SHA_BLOCKSIZE); + ctx->data[14] = hi_bit_count; + ctx->data[15] = lo_bit_count; + sha_transform(ctx); + + memcpy (digest, ctx->digest, 20); +} |