packages/shasum: Add a sha256sum utility with little dependencies

    To avoid weird requirements add a sha256sum tool to OpenEmbedded
    directly. This will be part of the OE manifest and be guarded
    by the monotone OE trust chain.

4 files changed, 446 insertions, 0 deletions

diff --git a/packages/shasum/files/.mtn2git_empty b/packages/shasum/files/.mtn2git_empty
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/packages/shasum/files/.mtn2git_empty
diff --git a/packages/shasum/files/main.c b/packages/shasum/files/main.c
new file mode 100644
index 0000000000..0748a94f3a
--- /dev/null
+++ b/packages/shasum/files/main.c
@@ -0,0 +1,60 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "mhash_sha256.h"
+
+/*
+ * from driver.c of mhash
+ */
+static const char hexconvtab[] = "0123456789abcdef";
+
+static char *
+bin2hex(const unsigned char *old, const size_t oldlen, size_t * newlen)
+{
+    unsigned char *new = NULL;
+    int i, j;
+
+    new = (char *) malloc(oldlen * 2 * sizeof(char) + 1);
+    if (!new)
+        return (new);
+
+    for (i = j = 0; i < oldlen; i++) {
+        new[j++] = hexconvtab[old[i] >> 4];
+        new[j++] = hexconvtab[old[i] & 15];
+    }
+    new[j] = '\0';
+
+    if (newlen)
+        *newlen = oldlen * 2 * sizeof(char);
+
+    return (new);
+}
+
+
+int main(int argc, char** argv)
+{
+    FILE *file;
+    size_t n;
+    SHA256_CTX ctx;
+    unsigned char buf[1024];
+    byte output[33];
+
+    if ( argc <= 1 ) {
+        return EXIT_FAILURE;
+    }
+
+    if ( (file=fopen(argv[1], "rb")) == NULL ) {
+        return EXIT_FAILURE;
+    }
+
+    sha256_init(&ctx);
+
+    while ( (n=fread( buf, 1, sizeof(buf), file)) > 0 )
+        sha256_update(&ctx, buf, n );
+
+    sha256_final(&ctx);
+    sha256_digest(&ctx, output);
+
+    printf("%s ?%s\n", bin2hex(output, 32, &n), argv[1]);
+    return EXIT_SUCCESS;
+}
diff --git a/packages/shasum/files/mhash_sha256.h b/packages/shasum/files/mhash_sha256.h
new file mode 100644
index 0000000000..46090c5f3e
--- /dev/null
+++ b/packages/shasum/files/mhash_sha256.h
@@ -0,0 +1,64 @@
+/* sha.h
+ *
+ * The sha1 and sha256 hash functions.
+ */
+
+/* nettle, low-level cryptographics library
+ *
+ * Copyright (C) 2001 Niels Möller
+ *  
+ * The nettle library is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or (at your
+ * option) any later version.
+ * 
+ * The nettle library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+ * License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with the nettle library; see the file COPYING.LIB.  If not, write to
+ * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+ 
+#ifndef NETTLE_SHA_H_INCLUDED
+#define NETTLE_SHA_H_INCLUDED
+
+#include <inttypes.h>
+
+typedef uint32_t word32;
+typedef unsigned char byte;
+
+
+/* SHA256 */
+
+#define SHA256_DIGEST_SIZE 32
+#define SHA256_DATA_SIZE 64
+
+/* Digest is kept internally as 8 32-bit words. */
+#define _SHA256_DIGEST_LENGTH 8
+
+typedef struct sha256_ctx
+{
+  word32 state[_SHA256_DIGEST_LENGTH];    /* State variables */
+  word32 count_low, count_high;           /* 64-bit block count */
+  byte block[SHA256_DATA_SIZE];          /* SHA256 data buffer */
+  unsigned int index;                       /* index into buffer */
+} SHA256_CTX;
+
+void
+sha256_init(struct sha256_ctx *ctx);
+
+void
+sha256_update(struct sha256_ctx *ctx, const byte *data, unsigned length);
+
+void
+sha256_final(struct sha256_ctx *ctx);
+
+void
+sha256_digest(const struct sha256_ctx *ctx, byte *digest);
+
+
+#endif /* NETTLE_SHA_H_INCLUDED */
diff --git a/packages/shasum/files/sha256.c b/packages/shasum/files/sha256.c
new file mode 100644
index 0000000000..e2ee2c6b4e
--- /dev/null
+++ b/packages/shasum/files/sha256.c
@@ -0,0 +1,322 @@
+/* sha256.h
+ *
+ * The sha256 hash function.
+ */
+
+/* nettle, low-level cryptographics library
+ *
+ * Copyright (C) 2001 Niels Möller
+ *  
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * The nettle library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+ * License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with the nettle library; see the file COPYING.LIB.  If not, write to
+ * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+/* Modelled after the sha1.c code by Peter Gutmann. */
+
+#include "mhash_sha256.h"
+#include <stdlib.h>
+#include <string.h>
+
+
+#ifndef EXTRACT_UCHAR
+#define EXTRACT_UCHAR(p)  (*(unsigned char *)(p))
+#endif
+
+#define STRING2INT(s) ((((((EXTRACT_UCHAR(s) << 8)    \
+			 | EXTRACT_UCHAR(s+1)) << 8)  \
+			 | EXTRACT_UCHAR(s+2)) << 8)  \
+			 | EXTRACT_UCHAR(s+3))
+
+/* This has been modified in order to fit in mhash.
+ * --nmav.
+ */
+
+/* A block, treated as a sequence of 32-bit words. */
+#define SHA256_DATA_LENGTH 16
+
+#define ROTR(n,x) ((x)>>(n) | ((x)<<(32-(n))))
+#define SHR(n,x) ((x)>>(n))
+
+/* The SHA256 functions. The Choice function is the same as the SHA1
+   function f1, and the majority function is the same as the SHA1 f3
+   function. They can be optimized to save one boolean operation each
+   - thanks to Rich Schroeppel, rcs@cs.arizona.edu for discovering
+   this */
+
+/* #define Choice(x,y,z) ( ( (x) & (y) ) | ( ~(x) & (z) ) ) */
+#define Choice(x,y,z)   ( (z) ^ ( (x) & ( (y) ^ (z) ) ) )
+/* #define Majority(x,y,z) ( ((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)) ) */
+#define Majority(x,y,z) ( ((x) & (y)) ^ ((z) & ((x) ^ (y))) )
+
+#define S0(x) (ROTR(2,(x)) ^ ROTR(13,(x)) ^ ROTR(22,(x)))
+#define S1(x) (ROTR(6,(x)) ^ ROTR(11,(x)) ^ ROTR(25,(x)))
+
+#define s0(x) (ROTR(7,(x)) ^ ROTR(18,(x)) ^ SHR(3,(x)))
+#define s1(x) (ROTR(17,(x)) ^ ROTR(19,(x)) ^ SHR(10,(x)))
+
+/* Generated by the shadata program. */
+static const word32 K[64] = {
+	0x428a2f98UL, 0x71374491UL, 0xb5c0fbcfUL, 0xe9b5dba5UL,
+	0x3956c25bUL, 0x59f111f1UL, 0x923f82a4UL, 0xab1c5ed5UL,
+	0xd807aa98UL, 0x12835b01UL, 0x243185beUL, 0x550c7dc3UL,
+	0x72be5d74UL, 0x80deb1feUL, 0x9bdc06a7UL, 0xc19bf174UL,
+	0xe49b69c1UL, 0xefbe4786UL, 0xfc19dc6UL, 0x240ca1ccUL,
+	0x2de92c6fUL, 0x4a7484aaUL, 0x5cb0a9dcUL, 0x76f988daUL,
+	0x983e5152UL, 0xa831c66dUL, 0xb00327c8UL, 0xbf597fc7UL,
+	0xc6e00bf3UL, 0xd5a79147UL, 0x6ca6351UL, 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,
+};
+
+/* The initial expanding function.  The hash function is defined over an
+   64-word expanded input array W, where the first 16 are copies of the input
+   data, and the remaining 64 are defined by
+
+        W[ t ] = s1(W[t-2] + W[t-7] + s0(W[i-15] + W[i-16]
+
+   This implementation generates these values on the fly in a circular
+   buffer - thanks to Colin Plumb, colin@nyx10.cs.du.edu for this
+   optimization.
+*/
+
+#define EXPAND(W,i) \
+( W[(i) & 15 ] += (s1(W[((i)-2) & 15]) + W[((i)-7) & 15] + s0(W[((i)-15) & 15])) )
+
+/* The prototype SHA sub-round.  The fundamental sub-round is:
+
+        T1 = h + S1(e) + Choice(e,f,g) + K[t] + W[t]
+	T2 = S0(a) + Majority(a,b,c)
+	a' = T1+T2
+	b' = a
+	c' = b
+	d' = c
+	e' = d + T1
+	f' = e
+	g' = f
+	h' = g
+
+   but this is implemented by unrolling the loop 8 times and renaming
+   the variables
+   ( h, a, b, c, d, e, f, g ) = ( a, b, c, d, e, f, g, h ) each
+   iteration. This code is then replicated 8, using the next 8 values
+   from the W[] array each time */
+
+/* FIXME: We can probably reorder this to optimize away at least one
+ * of T1 and T2. It's crucial that DATA is only used once, as that
+ * argument will have side effects. */
+#define ROUND(a,b,c,d,e,f,g,h,k,data) do {		\
+  word32 T1 = h + S1(e) + Choice(e,f,g) + k + data;	\
+  word32 T2 = S0(a) + Majority(a,b,c);		\
+  d += T1;						\
+  h = T1 + T2;						\
+} while (0)
+
+/* Initialize the SHA values */
+
+void sha256_init(struct sha256_ctx *ctx)
+{
+	/* Initial values, also generated by the shadata program. */
+	static const word32 H0[_SHA256_DIGEST_LENGTH] = {
+		0x6a09e667UL, 0xbb67ae85UL, 0x3c6ef372UL, 0xa54ff53aUL,
+		0x510e527fUL, 0x9b05688cUL, 0x1f83d9abUL, 0x5be0cd19UL,
+	};
+
+	memcpy(ctx->state, H0, sizeof(H0));
+
+	/* Initialize bit count */
+	ctx->count_low = ctx->count_high = 0;
+
+	/* Initialize buffer */
+	ctx->index = 0;
+}
+
+/* Perform the SHA transformation.  Note that this code, like MD5, seems to
+   break some optimizing compilers due to the complexity of the expressions
+   and the size of the basic block.  It may be necessary to split it into
+   sections, e.g. based on the four subrounds
+
+   Note that this function destroys the data area */
+
+static void sha256_transform(word32 * state, word32 * data)
+{
+	word32 A, B, C, D, E, F, G, H;	/* Local vars */
+	unsigned i;
+	const word32 *k;
+	word32 *d;
+
+	/* Set up first buffer and local data buffer */
+	A = state[0];
+	B = state[1];
+	C = state[2];
+	D = state[3];
+	E = state[4];
+	F = state[5];
+	G = state[6];
+	H = state[7];
+
+	/* Heavy mangling */
+	/* First 16 subrounds that act on the original data */
+
+	for (i = 0, k = K, d = data; i < 16; i += 8, k += 8, d += 8) {
+		ROUND(A, B, C, D, E, F, G, H, k[0], d[0]);
+		ROUND(H, A, B, C, D, E, F, G, k[1], d[1]);
+		ROUND(G, H, A, B, C, D, E, F, k[2], d[2]);
+		ROUND(F, G, H, A, B, C, D, E, k[3], d[3]);
+		ROUND(E, F, G, H, A, B, C, D, k[4], d[4]);
+		ROUND(D, E, F, G, H, A, B, C, k[5], d[5]);
+		ROUND(C, D, E, F, G, H, A, B, k[6], d[6]);
+		ROUND(B, C, D, E, F, G, H, A, k[7], d[7]);
+	}
+
+	for (; i < 64; i += 16, k += 16) {
+		ROUND(A, B, C, D, E, F, G, H, k[0], EXPAND(data, 0));
+		ROUND(H, A, B, C, D, E, F, G, k[1], EXPAND(data, 1));
+		ROUND(G, H, A, B, C, D, E, F, k[2], EXPAND(data, 2));
+		ROUND(F, G, H, A, B, C, D, E, k[3], EXPAND(data, 3));
+		ROUND(E, F, G, H, A, B, C, D, k[4], EXPAND(data, 4));
+		ROUND(D, E, F, G, H, A, B, C, k[5], EXPAND(data, 5));
+		ROUND(C, D, E, F, G, H, A, B, k[6], EXPAND(data, 6));
+		ROUND(B, C, D, E, F, G, H, A, k[7], EXPAND(data, 7));
+		ROUND(A, B, C, D, E, F, G, H, k[8], EXPAND(data, 8));
+		ROUND(H, A, B, C, D, E, F, G, k[9], EXPAND(data, 9));
+		ROUND(G, H, A, B, C, D, E, F, k[10], EXPAND(data, 10));
+		ROUND(F, G, H, A, B, C, D, E, k[11], EXPAND(data, 11));
+		ROUND(E, F, G, H, A, B, C, D, k[12], EXPAND(data, 12));
+		ROUND(D, E, F, G, H, A, B, C, k[13], EXPAND(data, 13));
+		ROUND(C, D, E, F, G, H, A, B, k[14], EXPAND(data, 14));
+		ROUND(B, C, D, E, F, G, H, A, k[15], EXPAND(data, 15));
+	}
+
+	/* Update state */
+	state[0] += A;
+	state[1] += B;
+	state[2] += C;
+	state[3] += D;
+	state[4] += E;
+	state[5] += F;
+	state[6] += G;
+	state[7] += H;
+}
+
+static void sha256_block(struct sha256_ctx *ctx, const byte * block)
+{
+	word32 data[SHA256_DATA_LENGTH];
+	int i;
+
+	/* Update block count */
+	if (!++ctx->count_low)
+		++ctx->count_high;
+
+	/* Endian independent conversion */
+	for (i = 0; i < SHA256_DATA_LENGTH; i++, block += 4)
+		data[i] = STRING2INT(block);
+
+	sha256_transform(ctx->state, data);
+}
+
+void
+sha256_update(struct sha256_ctx *ctx, const byte * buffer, unsigned length)
+{
+	if (ctx->index) {	/* Try to fill partial block */
+		unsigned left = SHA256_DATA_SIZE - ctx->index;
+		if (length < left) {
+			memcpy(ctx->block + ctx->index, buffer, length);
+			ctx->index += length;
+			return;	/* Finished */
+		} else {
+			memcpy(ctx->block + ctx->index, buffer, left);
+			sha256_block(ctx, ctx->block);
+			buffer += left;
+			length -= left;
+		}
+	}
+	while (length >= SHA256_DATA_SIZE) {
+		sha256_block(ctx, buffer);
+		buffer += SHA256_DATA_SIZE;
+		length -= SHA256_DATA_SIZE;
+	}
+	/* Buffer leftovers */
+	/* NOTE: The corresponding sha1 code checks for the special case length == 0.
+	 * That seems supoptimal, as I suspect it increases the number of branches. */
+
+	memcpy(ctx->block, buffer, length);
+	ctx->index = length;
+}
+
+/* Final wrapup - pad to SHA1_DATA_SIZE-byte boundary with the bit pattern
+   1 0* (64-bit count of bits processed, MSB-first) */
+
+void sha256_final(struct sha256_ctx *ctx)
+{
+	word32 data[SHA256_DATA_LENGTH];
+	int i;
+	int words;
+
+	i = ctx->index;
+
+	/* Set the first char of padding to 0x80.  This is safe since there is
+	   always at least one byte free */
+
+/*  assert(i < SHA256_DATA_SIZE);
+ */
+	ctx->block[i++] = 0x80;
+
+	/* Fill rest of word */
+	for (; i & 3; i++)
+		ctx->block[i] = 0;
+
+	/* i is now a multiple of the word size 4 */
+	words = i >> 2;
+	for (i = 0; i < words; i++)
+		data[i] = STRING2INT(ctx->block + 4 * i);
+
+	if (words > (SHA256_DATA_LENGTH - 2)) {	/* No room for length in this block. Process it and
+						 * pad with another one */
+		for (i = words; i < SHA256_DATA_LENGTH; i++)
+			data[i] = 0;
+		sha256_transform(ctx->state, data);
+		for (i = 0; i < (SHA256_DATA_LENGTH - 2); i++)
+			data[i] = 0;
+	} else
+		for (i = words; i < SHA256_DATA_LENGTH - 2; i++)
+			data[i] = 0;
+
+	/* There are 512 = 2^9 bits in one block */
+	data[SHA256_DATA_LENGTH - 2] =
+	    (ctx->count_high << 9) | (ctx->count_low >> 23);
+	data[SHA256_DATA_LENGTH - 1] =
+	    (ctx->count_low << 9) | (ctx->index << 3);
+	sha256_transform(ctx->state, data);
+}
+
+void sha256_digest(const struct sha256_ctx *ctx, byte * s)
+{
+	int i;
+
+	if (s!=NULL)
+		for (i = 0; i < _SHA256_DIGEST_LENGTH; i++) {
+			*s++ = ctx->state[i] >> 24;
+			*s++ = 0xff & (ctx->state[i] >> 16);
+			*s++ = 0xff & (ctx->state[i] >> 8);
+			*s++ = 0xff & ctx->state[i];
+		}
+}
+