jcs
/subtext
/amendments
/7
sha2: Import SHA256 code from OpenBSD
Little-endian support was removed, along with SHA384/SHA512 support
jcs made amendment 7 over 2 years ago
--- sha2.c Fri Dec 3 16:54:42 2021
+++ sha2.c Fri Dec 3 16:54:42 2021
@@ -0,0 +1,363 @@
+/* $OpenBSD: sha2.c,v 1.19 2021/03/12 10:22:46 jsg Exp $ */
+
+/*
+ * FILE: sha2.c
+ * AUTHOR: Aaron D. Gifford <me@aarongifford.com>
+ *
+ * Copyright (c) 2000-2001, Aaron D. Gifford
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the copyright holder nor the names of contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTOR(S) ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTOR(S) BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $From: sha2.c,v 1.1 2001/11/08 00:01:51 adg Exp adg $
+ */
+
+#include <string.h>
+#include "sha2.h"
+
+char *SHA256End(SHA2_CTX *ctx, char *buf);
+
+/*** SHA-256/384/512 Machine Architecture Definitions *****************/
+/*
+ * BYTE_ORDER NOTE:
+ *
+ * Please make sure that your system defines BYTE_ORDER. If your
+ * architecture is little-endian, make sure it also defines
+ * LITTLE_ENDIAN and that the two (BYTE_ORDER and LITTLE_ENDIAN) are
+ * equivalent.
+ *
+ * If your system does not define the above, then you can do so by
+ * hand like this:
+ *
+ * #define LITTLE_ENDIAN 1234
+ * #define BIG_ENDIAN 4321
+ *
+ * And for little-endian machines, add:
+ *
+ * #define BYTE_ORDER LITTLE_ENDIAN
+ *
+ * Or for big-endian machines:
+ *
+ * #define BYTE_ORDER BIG_ENDIAN
+ *
+ * The FreeBSD machine this was written on defines BYTE_ORDER
+ * appropriately by including <sys/types.h> (which in turn includes
+ * <machine/endian.h> where the appropriate definitions are actually
+ * made).
+ */
+#if !defined(BYTE_ORDER) || (BYTE_ORDER != BIG_ENDIAN)
+#error little-endian support was removed
+#endif
+
+
+/*** SHA-256 Various Length Definitions ***********************/
+/* NOTE: Most of these are in sha2.h */
+#define SHA256_SHORT_BLOCK_LENGTH (SHA256_BLOCK_LENGTH - 8)
+
+/*
+ * Macro for incrementally adding the unsigned 32-bit integer n to the
+ * unsigned 64-bit integer (represented using a two-element array of
+ * 32-bit words):
+ */
+#define ADDINC64(w,n) { \
+ (w)[0] += (u_int32_t)(n); \
+ if ((w)[0] < (n)) { \
+ (w)[1]++; \
+ } \
+}
+
+/*** THE SIX LOGICAL FUNCTIONS ****************************************/
+/*
+ * Bit shifting and rotation (used by the six SHA-XYZ logical functions:
+ *
+ * NOTE: The naming of R and S appears backwards here (R is a SHIFT and
+ * S is a ROTATION) because the SHA-256/384/512 description document
+ * (see http://csrc.nist.gov/cryptval/shs/sha256-384-512.pdf) uses this
+ * same "backwards" definition.
+ */
+/* Shift-right (used in SHA-256: */
+#define R(b,x) ((x) >> (b))
+/* 32-bit Rotate-right (used in SHA-256): */
+#define S32(b,x) (((x) >> (b)) | ((x) << (32 - (b))))
+
+/* Two of six logical functions used in SHA-256: */
+#define Ch(x,y,z) (((x) & (y)) ^ ((~(x)) & (z)))
+#define Maj(x,y,z) (((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)))
+
+/* Four of six logical functions used in SHA-256: */
+#define Sigma0_256(x) (S32(2, (x)) ^ S32(13, (x)) ^ S32(22, (x)))
+#define Sigma1_256(x) (S32(6, (x)) ^ S32(11, (x)) ^ S32(25, (x)))
+#define sigma0_256(x) (S32(7, (x)) ^ S32(18, (x)) ^ R(3 , (x)))
+#define sigma1_256(x) (S32(17, (x)) ^ S32(19, (x)) ^ R(10, (x)))
+
+/*** INTERNAL FUNCTION PROTOTYPES *************************************/
+/* NOTE: These should not be accessed directly from outside this
+ * library -- they are intended for private internal visibility/use
+ * only.
+ */
+void SHA256Transform(u_int32_t *, const u_int8_t *);
+
+
+/*** SHA-XYZ INITIAL HASH VALUES AND CONSTANTS ************************/
+/* Hash constant words K for SHA-256: */
+const static u_int32_t K256[64] = {
+ 0x428a2f98UL, 0x71374491UL, 0xb5c0fbcfUL, 0xe9b5dba5UL,
+ 0x3956c25bUL, 0x59f111f1UL, 0x923f82a4UL, 0xab1c5ed5UL,
+ 0xd807aa98UL, 0x12835b01UL, 0x243185beUL, 0x550c7dc3UL,
+ 0x72be5d74UL, 0x80deb1feUL, 0x9bdc06a7UL, 0xc19bf174UL,
+ 0xe49b69c1UL, 0xefbe4786UL, 0x0fc19dc6UL, 0x240ca1ccUL,
+ 0x2de92c6fUL, 0x4a7484aaUL, 0x5cb0a9dcUL, 0x76f988daUL,
+ 0x983e5152UL, 0xa831c66dUL, 0xb00327c8UL, 0xbf597fc7UL,
+ 0xc6e00bf3UL, 0xd5a79147UL, 0x06ca6351UL, 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
+};
+
+/* Initial hash value H for SHA-256: */
+const static u_int32_t sha256_initial_hash_value[8] = {
+ 0x6a09e667UL,
+ 0xbb67ae85UL,
+ 0x3c6ef372UL,
+ 0xa54ff53aUL,
+ 0x510e527fUL,
+ 0x9b05688cUL,
+ 0x1f83d9abUL,
+ 0x5be0cd19UL
+};
+
+
+/*** SHA-256: *********************************************************/
+void
+SHA256Init(SHA2_CTX *context)
+{
+ memcpy(context->state.st32, sha256_initial_hash_value,
+ SHA256_DIGEST_LENGTH);
+ memset(context->buffer, 0, SHA256_BLOCK_LENGTH);
+ context->bitcount[0] = 0;
+ context->bitcount[1] = 0;
+}
+
+void
+SHA256Transform(u_int32_t *state, const u_int8_t *data)
+{
+ u_int32_t a, b, c, d, e, f, g, h, s0, s1;
+ u_int32_t T1, T2, W256[16];
+ int j;
+
+ /* Initialize registers with the prev. intermediate value */
+ a = state[0];
+ b = state[1];
+ c = state[2];
+ d = state[3];
+ e = state[4];
+ f = state[5];
+ g = state[6];
+ h = state[7];
+
+ j = 0;
+ do {
+ W256[j] = (u_int32_t)data[3] | ((u_int32_t)data[2] << 8) |
+ ((u_int32_t)data[1] << 16) | ((u_int32_t)data[0] << 24);
+ data += 4;
+ /* Apply the SHA-256 compression function to update a..h */
+ T1 = h + Sigma1_256(e) + Ch(e, f, g) + K256[j] + W256[j];
+ T2 = Sigma0_256(a) + Maj(a, b, c);
+ h = g;
+ g = f;
+ f = e;
+ e = d + T1;
+ d = c;
+ c = b;
+ b = a;
+ a = T1 + T2;
+
+ j++;
+ } while (j < 16);
+
+ do {
+ /* Part of the message block expansion: */
+ s0 = W256[(j+1)&0x0f];
+ s0 = sigma0_256(s0);
+ s1 = W256[(j+14)&0x0f];
+ s1 = sigma1_256(s1);
+
+ /* Apply the SHA-256 compression function to update a..h */
+ T1 = h + Sigma1_256(e) + Ch(e, f, g) + K256[j] +
+ (W256[j&0x0f] += s1 + W256[(j+9)&0x0f] + s0);
+ T2 = Sigma0_256(a) + Maj(a, b, c);
+ h = g;
+ g = f;
+ f = e;
+ e = d + T1;
+ d = c;
+ c = b;
+ b = a;
+ a = T1 + T2;
+
+ j++;
+ } while (j < 64);
+
+ /* Compute the current intermediate hash value */
+ state[0] += a;
+ state[1] += b;
+ state[2] += c;
+ state[3] += d;
+ state[4] += e;
+ state[5] += f;
+ state[6] += g;
+ state[7] += h;
+
+ /* Clean up */
+ a = b = c = d = e = f = g = h = T1 = T2 = 0;
+}
+
+void
+SHA256Update(SHA2_CTX *context, const void *dataptr, size_t len)
+{
+ const uint8_t *data = dataptr;
+ size_t freespace, usedspace;
+
+ /* Calling with no data is valid (we do nothing) */
+ if (len == 0)
+ return;
+
+ usedspace = (context->bitcount[0] >> 3) % SHA256_BLOCK_LENGTH;
+ if (usedspace > 0) {
+ /* Calculate how much free space is available in the buffer */
+ freespace = SHA256_BLOCK_LENGTH - usedspace;
+
+ if (len >= freespace) {
+ /* Fill the buffer completely and process it */
+ memcpy(&context->buffer[usedspace], data, freespace);
+ ADDINC64(context->bitcount, freespace << 3);
+ len -= freespace;
+ data += freespace;
+ SHA256Transform(context->state.st32, context->buffer);
+ } else {
+ /* The buffer is not yet full */
+ memcpy(&context->buffer[usedspace], data, len);
+ ADDINC64(context->bitcount, len << 3);
+ /* Clean up: */
+ usedspace = freespace = 0;
+ return;
+ }
+ }
+ while (len >= SHA256_BLOCK_LENGTH) {
+ /* Process as many complete blocks as we can */
+ SHA256Transform(context->state.st32, data);
+ ADDINC64(context->bitcount, SHA256_BLOCK_LENGTH << 3);
+ len -= SHA256_BLOCK_LENGTH;
+ data += SHA256_BLOCK_LENGTH;
+ }
+ if (len > 0) {
+ /* There's left-overs, so save 'em */
+ memcpy(context->buffer, data, len);
+ ADDINC64(context->bitcount, len << 3);
+ }
+ /* Clean up: */
+ usedspace = freespace = 0;
+}
+
+void
+SHA256Final(u_int8_t digest[], SHA2_CTX *context)
+{
+ unsigned int usedspace;
+
+ usedspace = (context->bitcount[0] >> 3) % SHA256_BLOCK_LENGTH;
+ if (usedspace > 0) {
+ /* Begin padding with a 1 bit: */
+ context->buffer[usedspace++] = 0x80;
+
+ if (usedspace <= SHA256_SHORT_BLOCK_LENGTH) {
+ /* Set-up for the last transform: */
+ memset(&context->buffer[usedspace], 0,
+ SHA256_SHORT_BLOCK_LENGTH - usedspace);
+ } else {
+ if (usedspace < SHA256_BLOCK_LENGTH) {
+ memset(&context->buffer[usedspace], 0,
+ SHA256_BLOCK_LENGTH - usedspace);
+ }
+ /* Do second-to-last transform: */
+ SHA256Transform(context->state.st32, context->buffer);
+
+ /* And set-up for the last transform: */
+ memset(context->buffer, 0,
+ SHA256_SHORT_BLOCK_LENGTH);
+ }
+ } else {
+ /* Set-up for the last transform: */
+ memset(context->buffer, 0, SHA256_SHORT_BLOCK_LENGTH);
+
+ /* Begin padding with a 1 bit: */
+ *context->buffer = 0x80;
+ }
+ /* Set the bit count: */
+ *(u_int32_t *)&context->buffer[SHA256_SHORT_BLOCK_LENGTH] = context->bitcount[1];
+ *(u_int32_t *)&context->buffer[SHA256_SHORT_BLOCK_LENGTH + 4] = context->bitcount[0];
+
+ /* Final transform: */
+ SHA256Transform(context->state.st32, context->buffer);
+ memcpy(digest, context->state.st32, SHA256_DIGEST_LENGTH);
+
+ /* Clean up state data: */
+ memset(context, 0, sizeof(*context));
+ usedspace = 0;
+}
+
+char *
+SHA256End(SHA2_CTX *ctx, char *buf)
+{
+ short i;
+ u_int8_t digest[SHA256_DIGEST_LENGTH];
+ static const char hex[] = "0123456789abcdef";
+
+ if (buf == NULL)
+ return NULL;
+
+ SHA256Final(digest, ctx);
+ for (i = 0; i < SHA256_DIGEST_LENGTH; i++) {
+ buf[i + i] = hex[digest[i] >> 4];
+ buf[i + i + 1] = hex[digest[i] & 0x0f];
+ }
+ buf[i + i] = '\0';
+ memset(digest, 0, sizeof(digest));
+ return (buf);
+}
+
+char *
+SHA256Data(const u_int8_t *data, size_t len, char *buf)
+{
+ SHA2_CTX ctx;
+
+ SHA256Init(&ctx);
+ SHA256Update(&ctx, data, len);
+ return SHA256End(&ctx, buf);
+}
--- sha2.h Fri Dec 3 16:39:49 2021
+++ sha2.h Fri Dec 3 16:39:49 2021
@@ -0,0 +1,68 @@
+/* $OpenBSD: sha2.h,v 1.5 2014/11/16 17:39:09 tedu Exp $ */
+
+/*
+ * FILE: sha2.h
+ * AUTHOR: Aaron D. Gifford <me@aarongifford.com>
+ *
+ * Copyright (c) 2000-2001, Aaron D. Gifford
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the copyright holder nor the names of contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTOR(S) ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTOR(S) BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $From: sha2.h,v 1.1 2001/11/08 00:02:01 adg Exp adg $
+ */
+
+#ifndef _SHA2_H
+#define _SHA2_H
+
+#include <stddef.h>
+
+typedef unsigned long u_int32_t;
+typedef unsigned char u_int8_t;
+typedef unsigned char uint8_t;
+#define BYTE_ORDER BIG_ENDIAN
+
+/*** SHA-256/384/512 Various Length Definitions ***********************/
+#define SHA256_BLOCK_LENGTH 64
+#define SHA256_DIGEST_LENGTH 32
+#define SHA256_DIGEST_STRING_LENGTH (SHA256_DIGEST_LENGTH * 2 + 1)
+#define SHA512_BLOCK_LENGTH 128
+
+/*** SHA-256/384/512 Context Structure *******************************/
+typedef struct _SHA2_CTX {
+ union {
+ u_int32_t st32[8];
+ } state;
+ /* u_int64_t bitcount[2]; */
+ u_int32_t bitcount[4];
+ u_int8_t buffer[SHA512_BLOCK_LENGTH];
+} SHA2_CTX;
+
+void SHA256Init(SHA2_CTX *);
+void SHA256Update(SHA2_CTX *, const void *, size_t);
+void SHA256Final(u_int8_t[SHA256_DIGEST_LENGTH], SHA2_CTX *);
+char *SHA256Data(const u_int8_t *data, size_t len, char *buf);
+
+#endif /* _SHA2_H */