michael@0: /*
michael@0:  * sha1.c
michael@0:  *
michael@0:  * an implementation of the Secure Hash Algorithm v.1 (SHA-1),
michael@0:  * specified in FIPS 180-1
michael@0:  *
michael@0:  * David A. McGrew
michael@0:  * Cisco Systems, Inc.
michael@0:  */
michael@0: 
michael@0: /*
michael@0:  *	
michael@0:  * Copyright (c) 2001-2006, Cisco Systems, Inc.
michael@0:  * All rights reserved.
michael@0:  * 
michael@0:  * Redistribution and use in source and binary forms, with or without
michael@0:  * modification, are permitted provided that the following conditions
michael@0:  * are met:
michael@0:  * 
michael@0:  *   Redistributions of source code must retain the above copyright
michael@0:  *   notice, this list of conditions and the following disclaimer.
michael@0:  * 
michael@0:  *   Redistributions in binary form must reproduce the above
michael@0:  *   copyright notice, this list of conditions and the following
michael@0:  *   disclaimer in the documentation and/or other materials provided
michael@0:  *   with the distribution.
michael@0:  * 
michael@0:  *   Neither the name of the Cisco Systems, Inc. nor the names of its
michael@0:  *   contributors may be used to endorse or promote products derived
michael@0:  *   from this software without specific prior written permission.
michael@0:  * 
michael@0:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
michael@0:  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
michael@0:  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
michael@0:  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
michael@0:  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
michael@0:  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
michael@0:  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
michael@0:  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
michael@0:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
michael@0:  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
michael@0:  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
michael@0:  * OF THE POSSIBILITY OF SUCH DAMAGE.
michael@0:  *
michael@0:  */
michael@0: 
michael@0: 
michael@0: #include "sha1.h"
michael@0: 
michael@0: debug_module_t mod_sha1 = {
michael@0:   0,                 /* debugging is off by default */
michael@0:   "sha-1"            /* printable module name       */
michael@0: };
michael@0: 
michael@0: /* SN == Rotate left N bits */
michael@0: #define S1(X)  ((X << 1)  | (X >> 31))
michael@0: #define S5(X)  ((X << 5)  | (X >> 27))
michael@0: #define S30(X) ((X << 30) | (X >> 2))
michael@0: 
michael@0: #define f0(B,C,D) ((B & C) | (~B & D))              
michael@0: #define f1(B,C,D) (B ^ C ^ D)
michael@0: #define f2(B,C,D) ((B & C) | (B & D) | (C & D))
michael@0: #define f3(B,C,D) (B ^ C ^ D)
michael@0: 
michael@0: /* 
michael@0:  * nota bene: the variable K0 appears in the curses library, so we 
michael@0:  * give longer names to these variables to avoid spurious warnings 
michael@0:  * on systems that uses curses
michael@0:  */
michael@0: 
michael@0: uint32_t SHA_K0 = 0x5A827999;   /* Kt for 0  <= t <= 19 */
michael@0: uint32_t SHA_K1 = 0x6ED9EBA1;   /* Kt for 20 <= t <= 39 */
michael@0: uint32_t SHA_K2 = 0x8F1BBCDC;   /* Kt for 40 <= t <= 59 */
michael@0: uint32_t SHA_K3 = 0xCA62C1D6;   /* Kt for 60 <= t <= 79 */
michael@0: 
michael@0: void
michael@0: sha1(const uint8_t *msg,  int octets_in_msg, uint32_t hash_value[5]) {
michael@0:   sha1_ctx_t ctx;
michael@0: 
michael@0:   sha1_init(&ctx);
michael@0:   sha1_update(&ctx, msg, octets_in_msg);
michael@0:   sha1_final(&ctx, hash_value);
michael@0: 
michael@0: }
michael@0: 
michael@0: /*
michael@0:  *  sha1_core(M, H) computes the core compression function, where M is
michael@0:  *  the next part of the message (in network byte order) and H is the
michael@0:  *  intermediate state { H0, H1, ...} (in host byte order)
michael@0:  *
michael@0:  *  this function does not do any of the padding required in the
michael@0:  *  complete SHA1 function
michael@0:  *
michael@0:  *  this function is used in the SEAL 3.0 key setup routines
michael@0:  *  (crypto/cipher/seal.c)
michael@0:  */
michael@0: 
michael@0: void
michael@0: sha1_core(const uint32_t M[16], uint32_t hash_value[5]) {
michael@0:   uint32_t H0;
michael@0:   uint32_t H1;
michael@0:   uint32_t H2;
michael@0:   uint32_t H3;
michael@0:   uint32_t H4;
michael@0:   uint32_t W[80];
michael@0:   uint32_t A, B, C, D, E, TEMP;
michael@0:   int t;
michael@0: 
michael@0:   /* copy hash_value into H0, H1, H2, H3, H4 */
michael@0:   H0 = hash_value[0];
michael@0:   H1 = hash_value[1];
michael@0:   H2 = hash_value[2];
michael@0:   H3 = hash_value[3];
michael@0:   H4 = hash_value[4];
michael@0: 
michael@0:   /* copy/xor message into array */
michael@0: 
michael@0:   W[0]  = be32_to_cpu(M[0]);
michael@0:   W[1]  = be32_to_cpu(M[1]);
michael@0:   W[2]  = be32_to_cpu(M[2]);
michael@0:   W[3]  = be32_to_cpu(M[3]);
michael@0:   W[4]  = be32_to_cpu(M[4]);
michael@0:   W[5]  = be32_to_cpu(M[5]);
michael@0:   W[6]  = be32_to_cpu(M[6]);
michael@0:   W[7]  = be32_to_cpu(M[7]);
michael@0:   W[8]  = be32_to_cpu(M[8]);
michael@0:   W[9]  = be32_to_cpu(M[9]);
michael@0:   W[10] = be32_to_cpu(M[10]);
michael@0:   W[11] = be32_to_cpu(M[11]);
michael@0:   W[12] = be32_to_cpu(M[12]);
michael@0:   W[13] = be32_to_cpu(M[13]);
michael@0:   W[14] = be32_to_cpu(M[14]);
michael@0:   W[15] = be32_to_cpu(M[15]);
michael@0:   TEMP = W[13] ^ W[8]  ^ W[2]  ^ W[0];  W[16] = S1(TEMP);
michael@0:   TEMP = W[14] ^ W[9]  ^ W[3]  ^ W[1];  W[17] = S1(TEMP);
michael@0:   TEMP = W[15] ^ W[10] ^ W[4]  ^ W[2];  W[18] = S1(TEMP);
michael@0:   TEMP = W[16] ^ W[11] ^ W[5]  ^ W[3];  W[19] = S1(TEMP);
michael@0:   TEMP = W[17] ^ W[12] ^ W[6]  ^ W[4];  W[20] = S1(TEMP);
michael@0:   TEMP = W[18] ^ W[13] ^ W[7]  ^ W[5];  W[21] = S1(TEMP);
michael@0:   TEMP = W[19] ^ W[14] ^ W[8]  ^ W[6];  W[22] = S1(TEMP);
michael@0:   TEMP = W[20] ^ W[15] ^ W[9]  ^ W[7];  W[23] = S1(TEMP);
michael@0:   TEMP = W[21] ^ W[16] ^ W[10] ^ W[8];  W[24] = S1(TEMP);
michael@0:   TEMP = W[22] ^ W[17] ^ W[11] ^ W[9];  W[25] = S1(TEMP);
michael@0:   TEMP = W[23] ^ W[18] ^ W[12] ^ W[10]; W[26] = S1(TEMP);
michael@0:   TEMP = W[24] ^ W[19] ^ W[13] ^ W[11]; W[27] = S1(TEMP);
michael@0:   TEMP = W[25] ^ W[20] ^ W[14] ^ W[12]; W[28] = S1(TEMP);
michael@0:   TEMP = W[26] ^ W[21] ^ W[15] ^ W[13]; W[29] = S1(TEMP);
michael@0:   TEMP = W[27] ^ W[22] ^ W[16] ^ W[14]; W[30] = S1(TEMP);
michael@0:   TEMP = W[28] ^ W[23] ^ W[17] ^ W[15]; W[31] = S1(TEMP);
michael@0: 
michael@0:   /* process the remainder of the array */
michael@0:   for (t=32; t < 80; t++) {
michael@0:     TEMP = W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16];
michael@0:     W[t] = S1(TEMP);      
michael@0:   }
michael@0: 
michael@0:   A = H0; B = H1; C = H2; D = H3; E = H4;
michael@0: 
michael@0:   for (t=0; t < 20; t++) {
michael@0:     TEMP = S5(A) + f0(B,C,D) + E + W[t] + SHA_K0;
michael@0:     E = D; D = C; C = S30(B); B = A; A = TEMP;
michael@0:   }
michael@0:   for (   ; t < 40; t++) {
michael@0:     TEMP = S5(A) + f1(B,C,D) + E + W[t] + SHA_K1;
michael@0:     E = D; D = C; C = S30(B); B = A; A = TEMP;
michael@0:   }
michael@0:   for (   ; t < 60; t++) {
michael@0:     TEMP = S5(A) + f2(B,C,D) + E + W[t] + SHA_K2;
michael@0:     E = D; D = C; C = S30(B); B = A; A = TEMP;
michael@0:   }
michael@0:   for (   ; t < 80; t++) {
michael@0:     TEMP = S5(A) + f3(B,C,D) + E + W[t] + SHA_K3;
michael@0:     E = D; D = C; C = S30(B); B = A; A = TEMP;
michael@0:   }
michael@0: 
michael@0:   hash_value[0] = H0 + A;
michael@0:   hash_value[1] = H1 + B;
michael@0:   hash_value[2] = H2 + C;
michael@0:   hash_value[3] = H3 + D;
michael@0:   hash_value[4] = H4 + E;
michael@0: 
michael@0:   return;
michael@0: }
michael@0: 
michael@0: void
michael@0: sha1_init(sha1_ctx_t *ctx) {
michael@0: 
michael@0:   /* initialize state vector */
michael@0:   ctx->H[0] = 0x67452301;
michael@0:   ctx->H[1] = 0xefcdab89;
michael@0:   ctx->H[2] = 0x98badcfe;
michael@0:   ctx->H[3] = 0x10325476;
michael@0:   ctx->H[4] = 0xc3d2e1f0;
michael@0: 
michael@0:   /* indicate that message buffer is empty */
michael@0:   ctx->octets_in_buffer = 0;
michael@0: 
michael@0:   /* reset message bit-count to zero */
michael@0:   ctx->num_bits_in_msg = 0;
michael@0: 
michael@0: }
michael@0: 
michael@0: void
michael@0: sha1_update(sha1_ctx_t *ctx, const uint8_t *msg, int octets_in_msg) {
michael@0:   int i;
michael@0:   uint8_t *buf = (uint8_t *)ctx->M;
michael@0: 
michael@0:   /* update message bit-count */
michael@0:   ctx->num_bits_in_msg += octets_in_msg * 8;
michael@0: 
michael@0:   /* loop over 16-word blocks of M */
michael@0:   while (octets_in_msg > 0) {
michael@0: 
michael@0:     if (octets_in_msg + ctx->octets_in_buffer >= 64) {
michael@0: 
michael@0:       /* 
michael@0:        * copy words of M into msg buffer until that buffer is full,
michael@0:        * converting them into host byte order as needed
michael@0:        */
michael@0:       octets_in_msg -= (64 - ctx->octets_in_buffer);
michael@0:       for (i=ctx->octets_in_buffer; i < 64; i++) 
michael@0: 	buf[i] = *msg++;
michael@0:       ctx->octets_in_buffer = 0;
michael@0: 
michael@0:       /* process a whole block */
michael@0: 
michael@0:       debug_print(mod_sha1, "(update) running sha1_core()", NULL);
michael@0: 
michael@0:       sha1_core(ctx->M, ctx->H);
michael@0: 
michael@0:     } else {
michael@0: 
michael@0:       debug_print(mod_sha1, "(update) not running sha1_core()", NULL);
michael@0: 
michael@0:       for (i=ctx->octets_in_buffer; 
michael@0: 	   i < (ctx->octets_in_buffer + octets_in_msg); i++)
michael@0: 	buf[i] = *msg++;
michael@0:       ctx->octets_in_buffer += octets_in_msg;
michael@0:       octets_in_msg = 0;
michael@0:     }
michael@0: 
michael@0:   }
michael@0: 
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * sha1_final(ctx, output) computes the result for ctx and copies it
michael@0:  * into the twenty octets located at *output
michael@0:  */
michael@0: 
michael@0: void
michael@0: sha1_final(sha1_ctx_t *ctx, uint32_t *output) {
michael@0:   uint32_t A, B, C, D, E, TEMP;
michael@0:   uint32_t W[80];  
michael@0:   int i, t;
michael@0: 
michael@0:   /*
michael@0:    * process the remaining octets_in_buffer, padding and terminating as
michael@0:    * necessary
michael@0:    */
michael@0:   {
michael@0:     int tail = ctx->octets_in_buffer % 4;
michael@0: 
michael@0:     /* copy/xor message into array */
michael@0:     for (i=0; i < (ctx->octets_in_buffer+3)/4; i++) 
michael@0:       W[i]  = be32_to_cpu(ctx->M[i]);
michael@0: 
michael@0:     /* set the high bit of the octet immediately following the message */
michael@0:     switch (tail) {
michael@0:     case (3):
michael@0:       W[i-1] = (be32_to_cpu(ctx->M[i-1]) & 0xffffff00) | 0x80;
michael@0:       W[i] = 0x0;
michael@0:       break;
michael@0:     case (2):      
michael@0:       W[i-1] = (be32_to_cpu(ctx->M[i-1]) & 0xffff0000) | 0x8000;
michael@0:       W[i] = 0x0;
michael@0:       break;
michael@0:     case (1):
michael@0:       W[i-1] = (be32_to_cpu(ctx->M[i-1]) & 0xff000000) | 0x800000;
michael@0:       W[i] = 0x0;
michael@0:       break;
michael@0:     case (0):
michael@0:       W[i] = 0x80000000;
michael@0:       break;
michael@0:     }
michael@0: 
michael@0:     /* zeroize remaining words */
michael@0:     for (i++   ; i < 15; i++)
michael@0:       W[i] = 0x0;
michael@0: 
michael@0:     /* 
michael@0:      * if there is room at the end of the word array, then set the
michael@0:      * last word to the bit-length of the message; otherwise, set that
michael@0:      * word to zero and then we need to do one more run of the
michael@0:      * compression algo.
michael@0:      */
michael@0:     if (ctx->octets_in_buffer < 56) 
michael@0:       W[15] = ctx->num_bits_in_msg;
michael@0:     else if (ctx->octets_in_buffer < 60)
michael@0:       W[15] = 0x0;
michael@0: 
michael@0:     /* process the word array */
michael@0:     for (t=16; t < 80; t++) {
michael@0:       TEMP = W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16];
michael@0:       W[t] = S1(TEMP);
michael@0:     }
michael@0: 
michael@0:     A = ctx->H[0]; 
michael@0:     B = ctx->H[1]; 
michael@0:     C = ctx->H[2]; 
michael@0:     D = ctx->H[3]; 
michael@0:     E = ctx->H[4];
michael@0: 
michael@0:     for (t=0; t < 20; t++) {
michael@0:       TEMP = S5(A) + f0(B,C,D) + E + W[t] + SHA_K0;
michael@0:       E = D; D = C; C = S30(B); B = A; A = TEMP;
michael@0:     }
michael@0:     for (   ; t < 40; t++) {
michael@0:       TEMP = S5(A) + f1(B,C,D) + E + W[t] + SHA_K1;
michael@0:       E = D; D = C; C = S30(B); B = A; A = TEMP;
michael@0:     }
michael@0:     for (   ; t < 60; t++) {
michael@0:       TEMP = S5(A) + f2(B,C,D) + E + W[t] + SHA_K2;
michael@0:       E = D; D = C; C = S30(B); B = A; A = TEMP;
michael@0:     }
michael@0:     for (   ; t < 80; t++) {
michael@0:       TEMP = S5(A) + f3(B,C,D) + E + W[t] + SHA_K3;
michael@0:       E = D; D = C; C = S30(B); B = A; A = TEMP;
michael@0:     }
michael@0: 
michael@0:     ctx->H[0] += A;
michael@0:     ctx->H[1] += B;
michael@0:     ctx->H[2] += C;
michael@0:     ctx->H[3] += D;
michael@0:     ctx->H[4] += E;
michael@0: 
michael@0:   }
michael@0: 
michael@0:   debug_print(mod_sha1, "(final) running sha1_core()", NULL);
michael@0: 
michael@0:   if (ctx->octets_in_buffer >= 56) {
michael@0: 
michael@0:     debug_print(mod_sha1, "(final) running sha1_core() again", NULL);
michael@0: 
michael@0:     /* we need to do one final run of the compression algo */
michael@0: 
michael@0:     /* 
michael@0:      * set initial part of word array to zeros, and set the 
michael@0:      * final part to the number of bits in the message
michael@0:      */
michael@0:     for (i=0; i < 15; i++)
michael@0:       W[i] = 0x0;
michael@0:     W[15] = ctx->num_bits_in_msg;
michael@0: 
michael@0:     /* process the word array */
michael@0:     for (t=16; t < 80; t++) {
michael@0:       TEMP = W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16];
michael@0:       W[t] = S1(TEMP);
michael@0:     }
michael@0: 
michael@0:     A = ctx->H[0]; 
michael@0:     B = ctx->H[1]; 
michael@0:     C = ctx->H[2]; 
michael@0:     D = ctx->H[3]; 
michael@0:     E = ctx->H[4];
michael@0: 
michael@0:     for (t=0; t < 20; t++) {
michael@0:       TEMP = S5(A) + f0(B,C,D) + E + W[t] + SHA_K0;
michael@0:       E = D; D = C; C = S30(B); B = A; A = TEMP;
michael@0:     }
michael@0:     for (   ; t < 40; t++) {
michael@0:       TEMP = S5(A) + f1(B,C,D) + E + W[t] + SHA_K1;
michael@0:       E = D; D = C; C = S30(B); B = A; A = TEMP;
michael@0:     }
michael@0:     for (   ; t < 60; t++) {
michael@0:       TEMP = S5(A) + f2(B,C,D) + E + W[t] + SHA_K2;
michael@0:       E = D; D = C; C = S30(B); B = A; A = TEMP;
michael@0:     }
michael@0:     for (   ; t < 80; t++) {
michael@0:       TEMP = S5(A) + f3(B,C,D) + E + W[t] + SHA_K3;
michael@0:       E = D; D = C; C = S30(B); B = A; A = TEMP;
michael@0:     }
michael@0: 
michael@0:     ctx->H[0] += A;
michael@0:     ctx->H[1] += B;
michael@0:     ctx->H[2] += C;
michael@0:     ctx->H[3] += D;
michael@0:     ctx->H[4] += E;
michael@0:   }
michael@0: 
michael@0:   /* copy result into output buffer */
michael@0:   output[0] = be32_to_cpu(ctx->H[0]);
michael@0:   output[1] = be32_to_cpu(ctx->H[1]);
michael@0:   output[2] = be32_to_cpu(ctx->H[2]);
michael@0:   output[3] = be32_to_cpu(ctx->H[3]);
michael@0:   output[4] = be32_to_cpu(ctx->H[4]);
michael@0: 
michael@0:   /* indicate that message buffer in context is empty */
michael@0:   ctx->octets_in_buffer = 0;
michael@0: 
michael@0:   return;
michael@0: }
michael@0: 
michael@0: 
michael@0: