crypto: import crypto layer from barebox

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

1 files changed, 306 insertions, 0 deletions

diff --git a/src/crypto/sha1.c b/src/crypto/sha1.c
new file mode 100644
index 0000000..cbde4d2
--- /dev/null
+++ b/src/crypto/sha1.c
@@ -0,0 +1,306 @@
+/*
+ * Cryptographic API.
+ *
+ * SHA1 Secure Hash Algorithm.
+ *
+ * Derived from cryptoapi implementation, adapted for in-place
+ * scatterlist interface.
+ *
+ * Copyright (c) Alan Smithee.
+ * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
+ * Copyright (c) Jean-Francois Dive <jef@linuxbe.org>
+ *
+ * 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.
+ *
+ */
+
+#include <common.h>
+#include <digest.h>
+#include <init.h>
+#include <linux/string.h>
+#include <asm/unaligned.h>
+#include <asm/byteorder.h>
+
+#include <crypto/sha.h>
+#include <crypto/internal.h>
+
+#define SHA_WORKSPACE_WORDS 16
+
+static int sha1_init(struct digest *desc)
+{
+	struct sha1_state *ctx = digest_ctx(desc);
+
+	ctx->count = 0;
+
+	ctx->state[0] = SHA1_H0;
+	ctx->state[1] = SHA1_H1;
+	ctx->state[2] = SHA1_H2;
+	ctx->state[3] = SHA1_H3;
+	ctx->state[4] = SHA1_H4;
+
+	return 0;
+}
+
+/*
+ * If you have 32 registers or more, the compiler can (and should)
+ * try to change the array[] accesses into registers. However, on
+ * machines with less than ~25 registers, that won't really work,
+ * and at least gcc will make an unholy mess of it.
+ *
+ * So to avoid that mess which just slows things down, we force
+ * the stores to memory to actually happen (we might be better off
+ * with a 'W(t)=(val);asm("":"+m" (W(t))' there instead, as
+ * suggested by Artur Skawina - that will also make gcc unable to
+ * try to do the silly "optimize away loads" part because it won't
+ * see what the value will be).
+ *
+ * Ben Herrenschmidt reports that on PPC, the C version comes close
+ * to the optimized asm with this (ie on PPC you don't want that
+ * 'volatile', since there are lots of registers).
+ *
+ * On ARM we get the best code generation by forcing a full memory barrier
+ * between each SHA_ROUND, otherwise gcc happily get wild with spilling and
+ * the stack frame size simply explode and performance goes down the drain.
+ */
+
+#ifdef CONFIG_X86
+  #define setW(x, val) (*(volatile __u32 *)&W(x) = (val))
+#elif defined(CONFIG_ARM)
+  #define setW(x, val) do { W(x) = (val); __asm__("":::"memory"); } while (0)
+#else
+  #define setW(x, val) (W(x) = (val))
+#endif
+
+/* This "rolls" over the 512-bit array */
+#define W(x) (array[(x)&15])
+
+/*
+ * Where do we get the source from? The first 16 iterations get it from
+ * the input data, the next mix it from the 512-bit array.
+ */
+#define SHA_SRC(t) get_unaligned_be32((__u32 *)data + t)
+#define SHA_MIX(t) rol32(W(t+13) ^ W(t+8) ^ W(t+2) ^ W(t), 1)
+
+#define SHA_ROUND(t, input, fn, constant, A, B, C, D, E) do { \
+	__u32 TEMP = input(t); setW(t, TEMP); \
+	E += TEMP + rol32(A,5) + (fn) + (constant); \
+	B = ror32(B, 2); } while (0)
+
+#define T_0_15(t, A, B, C, D, E)  SHA_ROUND(t, SHA_SRC, (((C^D)&B)^D) , 0x5a827999, A, B, C, D, E )
+#define T_16_19(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, (((C^D)&B)^D) , 0x5a827999, A, B, C, D, E )
+#define T_20_39(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, (B^C^D) , 0x6ed9eba1, A, B, C, D, E )
+#define T_40_59(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, ((B&C)+(D&(B^C))) , 0x8f1bbcdc, A, B, C, D, E )
+#define T_60_79(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, (B^C^D) ,  0xca62c1d6, A, B, C, D, E )
+
+/**
+ * sha_transform - single block SHA1 transform
+ *
+ * @digest: 160 bit digest to update
+ * @data:   512 bits of data to hash
+ * @array:  16 words of workspace (see note)
+ *
+ * This function generates a SHA1 digest for a single 512-bit block.
+ * Be warned, it does not handle padding and message digest, do not
+ * confuse it with the full FIPS 180-1 digest algorithm for variable
+ * length messages.
+ *
+ * Note: If the hash is security sensitive, the caller should be sure
+ * to clear the workspace. This is left to the caller to avoid
+ * unnecessary clears between chained hashing operations.
+ */
+static void sha_transform(__u32 *digest, const char *data, __u32 *array)
+{
+	__u32 A, B, C, D, E;
+
+	A = digest[0];
+	B = digest[1];
+	C = digest[2];
+	D = digest[3];
+	E = digest[4];
+
+	/* Round 1 - iterations 0-16 take their input from 'data' */
+	T_0_15( 0, A, B, C, D, E);
+	T_0_15( 1, E, A, B, C, D);
+	T_0_15( 2, D, E, A, B, C);
+	T_0_15( 3, C, D, E, A, B);
+	T_0_15( 4, B, C, D, E, A);
+	T_0_15( 5, A, B, C, D, E);
+	T_0_15( 6, E, A, B, C, D);
+	T_0_15( 7, D, E, A, B, C);
+	T_0_15( 8, C, D, E, A, B);
+	T_0_15( 9, B, C, D, E, A);
+	T_0_15(10, A, B, C, D, E);
+	T_0_15(11, E, A, B, C, D);
+	T_0_15(12, D, E, A, B, C);
+	T_0_15(13, C, D, E, A, B);
+	T_0_15(14, B, C, D, E, A);
+	T_0_15(15, A, B, C, D, E);
+
+	/* Round 1 - tail. Input from 512-bit mixing array */
+	T_16_19(16, E, A, B, C, D);
+	T_16_19(17, D, E, A, B, C);
+	T_16_19(18, C, D, E, A, B);
+	T_16_19(19, B, C, D, E, A);
+
+	/* Round 2 */
+	T_20_39(20, A, B, C, D, E);
+	T_20_39(21, E, A, B, C, D);
+	T_20_39(22, D, E, A, B, C);
+	T_20_39(23, C, D, E, A, B);
+	T_20_39(24, B, C, D, E, A);
+	T_20_39(25, A, B, C, D, E);
+	T_20_39(26, E, A, B, C, D);
+	T_20_39(27, D, E, A, B, C);
+	T_20_39(28, C, D, E, A, B);
+	T_20_39(29, B, C, D, E, A);
+	T_20_39(30, A, B, C, D, E);
+	T_20_39(31, E, A, B, C, D);
+	T_20_39(32, D, E, A, B, C);
+	T_20_39(33, C, D, E, A, B);
+	T_20_39(34, B, C, D, E, A);
+	T_20_39(35, A, B, C, D, E);
+	T_20_39(36, E, A, B, C, D);
+	T_20_39(37, D, E, A, B, C);
+	T_20_39(38, C, D, E, A, B);
+	T_20_39(39, B, C, D, E, A);
+
+	/* Round 3 */
+	T_40_59(40, A, B, C, D, E);
+	T_40_59(41, E, A, B, C, D);
+	T_40_59(42, D, E, A, B, C);
+	T_40_59(43, C, D, E, A, B);
+	T_40_59(44, B, C, D, E, A);
+	T_40_59(45, A, B, C, D, E);
+	T_40_59(46, E, A, B, C, D);
+	T_40_59(47, D, E, A, B, C);
+	T_40_59(48, C, D, E, A, B);
+	T_40_59(49, B, C, D, E, A);
+	T_40_59(50, A, B, C, D, E);
+	T_40_59(51, E, A, B, C, D);
+	T_40_59(52, D, E, A, B, C);
+	T_40_59(53, C, D, E, A, B);
+	T_40_59(54, B, C, D, E, A);
+	T_40_59(55, A, B, C, D, E);
+	T_40_59(56, E, A, B, C, D);
+	T_40_59(57, D, E, A, B, C);
+	T_40_59(58, C, D, E, A, B);
+	T_40_59(59, B, C, D, E, A);
+
+	/* Round 4 */
+	T_60_79(60, A, B, C, D, E);
+	T_60_79(61, E, A, B, C, D);
+	T_60_79(62, D, E, A, B, C);
+	T_60_79(63, C, D, E, A, B);
+	T_60_79(64, B, C, D, E, A);
+	T_60_79(65, A, B, C, D, E);
+	T_60_79(66, E, A, B, C, D);
+	T_60_79(67, D, E, A, B, C);
+	T_60_79(68, C, D, E, A, B);
+	T_60_79(69, B, C, D, E, A);
+	T_60_79(70, A, B, C, D, E);
+	T_60_79(71, E, A, B, C, D);
+	T_60_79(72, D, E, A, B, C);
+	T_60_79(73, C, D, E, A, B);
+	T_60_79(74, B, C, D, E, A);
+	T_60_79(75, A, B, C, D, E);
+	T_60_79(76, E, A, B, C, D);
+	T_60_79(77, D, E, A, B, C);
+	T_60_79(78, C, D, E, A, B);
+	T_60_79(79, B, C, D, E, A);
+
+	digest[0] += A;
+	digest[1] += B;
+	digest[2] += C;
+	digest[3] += D;
+	digest[4] += E;
+}
+
+static int sha1_update(struct digest *desc, const void *data,
+			     unsigned long len)
+{
+	struct sha1_state *sctx = digest_ctx(desc);
+	unsigned int partial, done;
+	const u8 *src;
+
+	partial = sctx->count % SHA1_BLOCK_SIZE;
+	sctx->count += len;
+	done = 0;
+	src = data;
+
+	if ((partial + len) >= SHA1_BLOCK_SIZE) {
+		u32 temp[SHA_WORKSPACE_WORDS];
+
+		if (partial) {
+			done = -partial;
+			memcpy(sctx->buffer + partial, data,
+			       done + SHA1_BLOCK_SIZE);
+			src = sctx->buffer;
+		}
+
+		do {
+			sha_transform(sctx->state, src, temp);
+			done += SHA1_BLOCK_SIZE;
+			src = data + done;
+		} while (done + SHA1_BLOCK_SIZE <= len);
+
+		memset(temp, 0, sizeof(temp));
+		partial = 0;
+	}
+	memcpy(sctx->buffer + partial, src, len - done);
+
+	return 0;
+}
+
+static int sha1_final(struct digest *desc, unsigned char *md)
+{
+	struct sha1_state *sctx = digest_ctx(desc);
+	__be32 *dst = (__be32 *)md;
+	u32 i, index, padlen;
+	__be64 bits;
+	static const u8 padding[64] = { 0x80, };
+
+	bits = cpu_to_be64(sctx->count << 3);
+
+	/* Pad out to 56 mod 64 */
+	index = sctx->count & 0x3f;
+	padlen = (index < 56) ? (56 - index) : ((64+56) - index);
+	sha1_update(desc, padding, padlen);
+
+	/* Append length */
+	sha1_update(desc, (const u8 *)&bits, sizeof(bits));
+
+	/* Store state in digest */
+	for (i = 0; i < 5; i++)
+		dst[i] = cpu_to_be32(sctx->state[i]);
+
+	/* Wipe context */
+	memset(sctx, 0, sizeof *sctx);
+
+	return 0;
+}
+
+static struct digest_algo m = {
+	.base = {
+		.name		=	"sha1",
+		.driver_name	=	"sha1-generic",
+		.priority	=	0,
+		.algo		=	HASH_ALGO_SHA1,
+	},
+
+	.init		= sha1_init,
+	.update		= sha1_update,
+	.final		= sha1_final,
+	.digest		= digest_generic_digest,
+	.verify		= digest_generic_verify,
+	.length		= SHA1_DIGEST_SIZE,
+	.ctx_length = sizeof(struct sha1_state),
+};
+
+static int sha1_digest_register(void)
+{
+	return digest_algo_register(&m);
+}
+device_initcall(sha1_digest_register);