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-rwxr-xr-xlibedsio/sha.c239
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diff --git a/libedsio/sha.c b/libedsio/sha.c
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+/* 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);
+}
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