[PATCH 03/16] Add sha1 implementation
Stefan Berger
stefanb at linux.vnet.ibm.com
Sat Aug 8 11:54:52 AEST 2015
The following patch adds a SHA1 implementation based on the algorithm
description in NIST FIPS PUB 180-4.
Signed-off-by: Stefan Berger <stefanb at linux.vnet.ibm.com>
---
lib/libtpm/Makefile | 2 +-
lib/libtpm/sha1.c | 197 ++++++++++++++++++++++++++++++++++++++++++++++++++++
lib/libtpm/sha1.h | 20 ++++++
3 files changed, 218 insertions(+), 1 deletion(-)
create mode 100644 lib/libtpm/sha1.c
create mode 100644 lib/libtpm/sha1.h
diff --git a/lib/libtpm/Makefile b/lib/libtpm/Makefile
index 53d3abb..f8ad468 100644
--- a/lib/libtpm/Makefile
+++ b/lib/libtpm/Makefile
@@ -24,7 +24,7 @@ TARGET = ../libtpm.a
all: $(TARGET)
-SRCS = tpm_drivers.c tcgbios.c
+SRCS = tpm_drivers.c tcgbios.c sha1.c
OBJS = $(SRCS:%.c=%.o)
diff --git a/lib/libtpm/sha1.c b/lib/libtpm/sha1.c
new file mode 100644
index 0000000..2454b8f
--- /dev/null
+++ b/lib/libtpm/sha1.c
@@ -0,0 +1,197 @@
+/*****************************************************************************
+ * Copyright (c) 2015 IBM Corporation
+ * All rights reserved.
+ * This program and the accompanying materials
+ * are made available under the terms of the BSD License
+ * which accompanies this distribution, and is available at
+ * http://www.opensource.org/licenses/bsd-license.php
+ *
+ * Contributors:
+ * IBM Corporation - initial implementation
+ *****************************************************************************/
+
+/*
+ * See: NIST standard for SHA-1 in FIPS PUB 180-4
+ */
+
+#include "byteorder.h"
+#include "sha1.h"
+#include "string.h"
+
+typedef struct _sha1_ctx {
+ uint32_t h[5];
+} sha1_ctx;
+
+static uint32_t rol(uint32_t data, uint8_t n)
+{
+ if (!n)
+ return data;
+ return (data << n) | (data >> (32 - n));
+}
+
+static void sha1_block(uint32_t *w, sha1_ctx *ctx)
+{
+ uint32_t i;
+ uint32_t a,b,c,d,e,f;
+ uint32_t tmp;
+ uint32_t idx;
+
+ /*
+ * FIPS 180-4 4.2.1: SHA1 Constants
+ */
+ static const uint32_t sha_ko[4] = {
+ 0x5a827999, 0x6ed9eba1, 0x8f1bbcdc, 0xca62c1d6
+ };
+
+ /*
+ * FIPS 180-4 6.1.2: step 1
+ *
+ * 0 <= i <= 15:
+ * W(t) = M(t)
+ * 16 <= i <= 79:
+ * W(t) = ROTL(W(t-3) XOR W(t-8) XOR W(t-14) XOR W(t-16), 1)
+ */
+
+ /* w(0)..(w15) already in big endian format */
+
+ for (i = 16; i <= 79; i++) {
+ tmp = w[i-3] ^ w[i-8] ^ w[i-14] ^ w[i-16];
+ w[i] = rol(tmp, 1);
+ }
+
+ /*
+ * step 2: a = H0, b = H1, c = H2, d = H3, e = H4.
+ */
+ a = ctx->h[0];
+ b = ctx->h[1];
+ c = ctx->h[2];
+ d = ctx->h[3];
+ e = ctx->h[4];
+
+ /*
+ * step 3: For i = 0 to 79:
+ * T = ROTL(a, 5) + f(i; b,c,d) + e + W(t) + K(t);
+ */
+ for (i = 0; i <= 79; i++) {
+ /*
+ * FIPS 180-4: 4.1.1 : definition of f(i; b,c,d)
+ */
+ if (i <= 19) {
+ /*
+ * 0 <= i <= 19:
+ * f(i; b,c,d) = (b AND c) OR ((NOT b) AND d)
+ */
+ f = (b & c) | ((b ^ 0xffffffff) & d);
+ idx = 0;
+ } else if (i <= 39) {
+ /*
+ * 20 <= i <= 39:
+ * f(i; b,c,d) = b XOR c XOR d
+ */
+ f = b ^ c ^ d;
+ idx = 1;
+ } else if (i <= 59) {
+ /*
+ * 40 <= i <= 59:
+ * f(i; b,c,d) = (b AND c) OR (b AND d) OR (c AND d)
+ */
+ f = (b & c) | (b & d) | (c & d);
+ idx = 2;
+ } else {
+ /*
+ * 60 <= i <= 79:
+ * f(i; b,c,d) = b XOR c XOR d
+ */
+ f = b ^ c ^ d;
+ idx = 3;
+ }
+
+ /*
+ * step 3:
+ * t = ROTL(a, 5) + f(t;b,c,d) + e + K(t) + W(t);
+ * e = d; d = c; c = ROTL(b, 30); b = a; a = t;
+ */
+ tmp = rol(a, 5) +
+ f +
+ e +
+ sha_ko[idx] +
+ w[i];
+ e = d;
+ d = c;
+ c = rol(b, 30);
+ b = a;
+ a = tmp;
+ }
+
+ /*
+ * step 4:
+ * H0 = a + H0, H1 = b + H1, H2 = c + H2, H3 = d + H3, H4 = e + H4
+ */
+ ctx->h[0] += a;
+ ctx->h[1] += b;
+ ctx->h[2] += c;
+ ctx->h[3] += d;
+ ctx->h[4] += e;
+}
+
+static void sha1_do(sha1_ctx *ctx, const uint8_t*data32, uint32_t length)
+{
+ uint32_t offset;
+ uint16_t num;
+ uint32_t bits = 0;
+ uint32_t w[80];
+ uint64_t tmp;
+
+ /* treat data in 64-byte chunks */
+ for (offset = 0; length - offset >= 64; offset += 64) {
+ memcpy(w, data32 + offset, 64);
+ sha1_block((uint32_t *)w, ctx);
+ bits += (64 * 8);
+ }
+
+ /* last block with less than 64 bytes */
+ num = length - offset;
+ bits += (num << 3);
+
+ memcpy(w, data32 + offset, num);
+ /*
+ * FIPS 180-4 5.1: Padding the Message
+ */
+ ((uint8_t *)w)[num] = 0x80;
+ if (64 - (num + 1) > 0)
+ memset( &((uint8_t *)w)[num + 1], 0, 64 - (num + 1));
+
+ if (num >= 56) {
+ /* cannot append number of bits here */
+ sha1_block((uint32_t *)w, ctx);
+ memset(w, 0, 60);
+ }
+
+ /* write number of bits to end of block */
+ tmp = bits;
+ memcpy(&w[14], &tmp, 8);
+
+ sha1_block(w, ctx);
+}
+
+uint32_t sha1(const uint8_t *data, uint32_t length, uint8_t *hash)
+{
+ sha1_ctx ctx = {
+ .h = {
+ /*
+ * FIPS 180-4: 6.1.1
+ * -> 5.3.1: initial hash value
+ */
+ 0x67452301,
+ 0xefcdab89,
+ 0x98badcfe,
+ 0x10325476,
+ 0xc3d2e1f0,
+ }
+ };
+
+ sha1_do(&ctx, data, length);
+ memcpy(hash, &ctx.h[0], 20);
+
+ return 0;
+}
diff --git a/lib/libtpm/sha1.h b/lib/libtpm/sha1.h
new file mode 100644
index 0000000..7fa3e03
--- /dev/null
+++ b/lib/libtpm/sha1.h
@@ -0,0 +1,20 @@
+/*****************************************************************************
+ * Copyright (c) 2015 IBM Corporation
+ * All rights reserved.
+ * This program and the accompanying materials
+ * are made available under the terms of the BSD License
+ * which accompanies this distribution, and is available at
+ * http://www.opensource.org/licenses/bsd-license.php
+ *
+ * Contributors:
+ * IBM Corporation - initial implementation
+ *****************************************************************************/
+
+#ifndef __SHA1_H
+#define __SHA1_H
+
+#include "types.h"
+
+uint32_t sha1(const uint8_t *data, uint32_t length, uint8_t *hash);
+
+#endif /* __SHA1_H */
--
1.9.3
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