/* SAMHAIN file system integrity testing */ /* Copyright (C) 2013 Rainer Wichmann */ /* */ /* 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. */ /* */ /* This program 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 General Public License for more details. */ /* */ /* You should have received a copy of the GNU General Public License */ /* along with this program; if not, write to the Free Software */ /* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include "config_xor.h" #include "samhain.h" #include "sh_checksum.h" #include #undef FIL__ #define FIL__ _("sh_checksum.c") /* * sha2.c * * Version 1.0.0beta1 * * Written by Aaron D. Gifford * * Copyright 2000 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(S) 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(S) 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. * */ /* Modified for use in samhain by R. Wichmann */ #if WORDS_BIGENDIAN #define SHA2_BIG_ENDIAN 4321 #define SHA2_BYTE_ORDER SHA2_BIG_ENDIAN #else #define SHA2_LITTLE_ENDIAN 1234 #define SHA2_BYTE_ORDER SHA2_LITTLE_ENDIAN #endif #if SHA2_BYTE_ORDER == SHA2_LITTLE_ENDIAN #define REVERSE32(w,x) { \ sha2_word32 tmp = (w); \ tmp = (tmp >> 16) | (tmp << 16); \ (x) = ((tmp & 0xff00ff00UL) >> 8) | ((tmp & 0x00ff00ffUL) << 8); \ } #define REVERSE64(w,x) { \ sha2_word64 tmp = (w); \ tmp = (tmp >> 32) | (tmp << 32); \ tmp = ((tmp & 0xff00ff00ff00ff00ULL) >> 8) | \ ((tmp & 0x00ff00ff00ff00ffULL) << 8); \ (x) = ((tmp & 0xffff0000ffff0000ULL) >> 16) | \ ((tmp & 0x0000ffff0000ffffULL) << 16); \ } #endif /* * Macro for incrementally adding the unsigned 64-bit integer n to the * unsigned 128-bit integer (represented using a two-element array of * 64-bit words): */ #define ADDINC128(w,n) { \ (w)[0] += (sha2_word64)(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, SHA-384, and SHA-512): */ #define R(b,x) ((x) >> (b)) /* 32-bit Rotate-right (used in SHA-256): */ #define S32(b,x) (((x) >> (b)) | ((x) << (32 - (b)))) /* 64-bit Rotate-right (used in SHA-384 and SHA-512): */ #define S64(b,x) (((x) >> (b)) | ((x) << (64 - (b)))) /* Two of six logical functions used in SHA-256, SHA-384, and SHA-512: */ #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 SHA256_Transform(SHA256_CTX*, const sha2_word32*); /*** SHA-XYZ INITIAL HASH VALUES AND CONSTANTS ************************/ /* Hash constant words K for SHA-256: */ static const sha2_word32 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: */ static const sha2_word32 sha256_initial_hash_value[8] = { 0x6a09e667UL, 0xbb67ae85UL, 0x3c6ef372UL, 0xa54ff53aUL, 0x510e527fUL, 0x9b05688cUL, 0x1f83d9abUL, 0x5be0cd19UL }; /* * Constant used by SHA256/384/512_End() functions for converting the * digest to a readable hexadecimal character string: */ static const char *sha2_hex_digits = "0123456789abcdef"; /*** SHA-256: *********************************************************/ void SHA256_Init(SHA256_CTX* context) { if (context == (SHA256_CTX*)0) { return; } memcpy(context->state, sha256_initial_hash_value, SHA256_DIGEST_LENGTH); /* bcopy(sha256_initial_hash_value, context->state, SHA256_DIGEST_LENGTH); */ memset(context->buffer, 0, SHA256_BLOCK_LENGTH); /* bzero(context->buffer, SHA256_BLOCK_LENGTH); */ context->bitcount = 0; } #ifdef SHA2_UNROLL_TRANSFORM /* Unrolled SHA-256 round macros: */ #if SHA2_BYTE_ORDER == SHA2_LITTLE_ENDIAN #define ROUND256_0_TO_15(a,b,c,d,e,f,g,h) \ REVERSE32(*data++, W256[j]); \ T1 = (h) + Sigma1_256(e) + Ch((e), (f), (g)) + \ K256[j] + W256[j]; \ (d) += T1; \ (h) = T1 + Sigma0_256(a) + Maj((a), (b), (c)); \ j++ #else /* SHA2_BYTE_ORDER == SHA2_LITTLE_ENDIAN */ #define ROUND256_0_TO_15(a,b,c,d,e,f,g,h) \ T1 = (h) + Sigma1_256(e) + Ch((e), (f), (g)) + \ K256[j] + (W256[j] = *data++); \ (d) += T1; \ (h) = T1 + Sigma0_256(a) + Maj((a), (b), (c)); \ j++ #endif /* SHA2_BYTE_ORDER == SHA2_LITTLE_ENDIAN */ #define ROUND256(a,b,c,d,e,f,g,h) \ s0 = W256[(j+1)&0x0f]; \ s0 = sigma0_256(s0); \ s1 = W256[(j+14)&0x0f]; \ s1 = sigma1_256(s1); \ T1 = (h) + Sigma1_256(e) + Ch((e), (f), (g)) + K256[j] + \ (W256[j&0x0f] += s1 + W256[(j+9)&0x0f] + s0); \ (d) += T1; \ (h) = T1 + Sigma0_256(a) + Maj((a), (b), (c)); \ j++ void SHA256_Transform(SHA256_CTX* context, const sha2_word32* data) { sha2_word32 a, b, c, d, e, f, g, h, s0, s1; sha2_word32 T1, *W256; int j; W256 = (sha2_word32*)context->buffer; /* Initialize registers with the prev. intermediate value */ a = context->state[0]; b = context->state[1]; c = context->state[2]; d = context->state[3]; e = context->state[4]; f = context->state[5]; g = context->state[6]; h = context->state[7]; j = 0; do { /* Rounds 0 to 15 (unrolled): */ ROUND256_0_TO_15(a,b,c,d,e,f,g,h); ROUND256_0_TO_15(h,a,b,c,d,e,f,g); ROUND256_0_TO_15(g,h,a,b,c,d,e,f); ROUND256_0_TO_15(f,g,h,a,b,c,d,e); ROUND256_0_TO_15(e,f,g,h,a,b,c,d); ROUND256_0_TO_15(d,e,f,g,h,a,b,c); ROUND256_0_TO_15(c,d,e,f,g,h,a,b); ROUND256_0_TO_15(b,c,d,e,f,g,h,a); } while (j < 16); /* Now for the remaining rounds to 64: */ do { ROUND256(a,b,c,d,e,f,g,h); ROUND256(h,a,b,c,d,e,f,g); ROUND256(g,h,a,b,c,d,e,f); ROUND256(f,g,h,a,b,c,d,e); ROUND256(e,f,g,h,a,b,c,d); ROUND256(d,e,f,g,h,a,b,c); ROUND256(c,d,e,f,g,h,a,b); ROUND256(b,c,d,e,f,g,h,a); } while (j < 64); /* Compute the current intermediate hash value */ context->state[0] += a; context->state[1] += b; context->state[2] += c; context->state[3] += d; context->state[4] += e; context->state[5] += f; context->state[6] += g; context->state[7] += h; /* Clean up */ a = b = c = d = e = f = g = h = T1 = 0; } #else /* SHA2_UNROLL_TRANSFORM */ void SHA256_Transform(SHA256_CTX* context, const sha2_word32* data) { sha2_word32 a, b, c, d, e, f, g, h, s0, s1; sha2_word32 T1, T2, *W256; int j; W256 = (sha2_word32*)context->buffer; /* Initialize registers with the prev. intermediate value */ a = context->state[0]; b = context->state[1]; c = context->state[2]; d = context->state[3]; e = context->state[4]; f = context->state[5]; g = context->state[6]; h = context->state[7]; j = 0; do { #if SHA2_BYTE_ORDER == SHA2_LITTLE_ENDIAN /* Copy data while converting to host byte order */ REVERSE32(*data++,W256[j]); /* Apply the SHA-256 compression function to update a..h */ T1 = h + Sigma1_256(e) + Ch(e, f, g) + K256[j] + W256[j]; #else /* SHA2_BYTE_ORDER == SHA2_LITTLE_ENDIAN */ /* Apply the SHA-256 compression function to update a..h with copy */ T1 = h + Sigma1_256(e) + Ch(e, f, g) + K256[j] + (W256[j] = *data++); #endif /* SHA2_BYTE_ORDER == SHA2_LITTLE_ENDIAN */ 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 */ context->state[0] += a; context->state[1] += b; context->state[2] += c; context->state[3] += d; context->state[4] += e; context->state[5] += f; context->state[6] += g; context->state[7] += h; /* Clean up */ a = b = c = d = e = f = g = h = T1 = T2 = 0; } #endif /* SHA2_UNROLL_TRANSFORM */ void SHA256_Update(SHA256_CTX* context, const sha2_byte *data, size_t len) { unsigned int freespace, usedspace; if (len == 0) { /* Calling with no data is valid - we do nothing */ return; } usedspace = (context->bitcount >> 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); /* bcopy(data, &context->buffer[usedspace], freespace); */ context->bitcount += freespace << 3; len -= freespace; data += freespace; SHA256_Transform(context, (sha2_word32*)context->buffer); } else { /* The buffer is not yet full */ memcpy(&context->buffer[usedspace], data, len); /* bcopy(data, &context->buffer[usedspace], len); */ context->bitcount += len << 3; /* Clean up: */ usedspace = freespace = 0; return; } } while (len >= SHA256_BLOCK_LENGTH) { /* Process as many complete blocks as we can */ SHA256_Transform(context, (const sha2_word32*)data); 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); /* bcopy(data, context->buffer, len); */ context->bitcount += len << 3; } /* Clean up: */ usedspace = freespace = 0; } void SHA256_Final(sha2_byte digest[], SHA256_CTX* context) { sha2_word32 *d = (sha2_word32*)digest; unsigned int usedspace; union { sha2_word64 bitcount; sha2_byte buffer[sizeof(sha2_word64)]; } sha2_union; /* If no digest buffer is passed, we don't bother doing this: */ if (digest != (sha2_byte*)0) { usedspace = (context->bitcount >> 3) % SHA256_BLOCK_LENGTH; #if SHA2_BYTE_ORDER == SHA2_LITTLE_ENDIAN /* Convert FROM host byte order */ REVERSE64(context->bitcount,context->bitcount); #endif 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: */ SHA256_Transform(context, (sha2_word32*)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 (with fix for gcc type-punning warning): */ sha2_union.bitcount = context->bitcount; memcpy (&context->buffer[SHA256_SHORT_BLOCK_LENGTH], sha2_union.buffer, sizeof(sha2_word64)); /* *(sha2_word64*) &context->buffer[SHA256_SHORT_BLOCK_LENGTH] = context->bitcount; */ /* Final transform: */ SHA256_Transform(context, (sha2_word32*)context->buffer); #if SHA2_BYTE_ORDER == SHA2_LITTLE_ENDIAN { /* Convert TO host byte order */ int j; for (j = 0; j < 8; j++) { REVERSE32(context->state[j],context->state[j]); *d++ = context->state[j]; } } #else memset(d, context->state, SHA256_DIGEST_LENGTH); /* bcopy(context->state, d, SHA256_DIGEST_LENGTH); */ #endif } /* Clean up state data: */ memset(context, 0, sizeof(context)); usedspace = 0; } #include "sh_utils.h" /* If buffer is of length KEYBUF_SIZE, the digest will fit */ char *SHA256_End(SHA256_CTX* context, char buffer[]) { sha2_byte digest[SHA256_DIGEST_LENGTH]; if (buffer != (char*)0) { SHA256_Final(digest, context); sh_util_base64_enc ((unsigned char *)buffer, digest, SHA256_DIGEST_LENGTH); } else { memset(context, 0, sizeof(context)); } memset(digest, 0, SHA256_DIGEST_LENGTH); return buffer; } char* SHA256_Data(const sha2_byte* data, size_t len, char digest[KEYBUF_SIZE]) { SHA256_CTX context; SHA256_Init(&context); SHA256_Update(&context, data, len); return SHA256_End(&context, digest); } char* SHA256_Base2Hex(char * b64digest, char * hexdigest) { int i; sha2_byte data[512]; sha2_byte *d; size_t len; char * buffer; len = strlen(b64digest); sh_util_base64_dec ((unsigned char*) data, (unsigned char *)b64digest, len); d = data; buffer = hexdigest; for (i = 0; i < SHA256_DIGEST_LENGTH; i++) { *buffer++ = sha2_hex_digits[(*d & 0xf0) >> 4]; *buffer++ = sha2_hex_digits[*d & 0x0f]; d++; } *buffer = (char)0; return hexdigest; } char * SHA256_ReplaceBaseByHex(const char * str, char * before, char after) { char keybuf[KEYBUF_SIZE]; char * s = strstr(str, before); if (s) { char * p; s += strlen(before); memcpy(keybuf, s, sizeof(keybuf)); keybuf[sizeof(keybuf)-1] = '\0'; p = strchr(keybuf, after); if (p) { char hexbuf[SHA256_DIGEST_STRING_LENGTH]; char * ret = SH_ALLOC(strlen(str) + 1 + sizeof(keybuf)); char * r = ret; *p = '\0'; SHA256_Base2Hex(keybuf, hexbuf); memcpy(ret, str, (s - str)); r += (int)(s - str); *r = '\0'; strcpy(r, hexbuf); /* flawfinder: ignore */ r += strlen(hexbuf); p = strchr(s, after); strcpy(r, p); /* flawfinder: ignore */ return ret; } } return NULL; } #ifdef SH_CUTEST #include #include "CuTest.h" void Test_sha256 (CuTest *tc) { char hexdigest[SHA256_DIGEST_STRING_LENGTH]; char b64digest[KEYBUF_SIZE]; char * b64; char * buffer; size_t len; sha2_byte data[512]; sha2_byte *d; int i; data[0] = '\0'; len = 0; b64 = SHA256_Data(data, len, b64digest); CuAssertPtrNotNull(tc, b64); len = strlen((char*)b64); sh_util_base64_dec (data, (unsigned char*)b64, len); d = data; buffer = hexdigest; for (i = 0; i < SHA256_DIGEST_LENGTH; i++) { *buffer++ = sha2_hex_digits[(*d & 0xf0) >> 4]; *buffer++ = sha2_hex_digits[*d & 0x0f]; d++; } *buffer = (char)0; CuAssertStrEquals(tc, hexdigest, "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"); memset(hexdigest, 0, sizeof(hexdigest)); buffer = SHA256_Base2Hex(b64digest, hexdigest); CuAssertPtrNotNull(tc, buffer); CuAssertStrEquals(tc, hexdigest, "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"); CuAssertStrEquals(tc, buffer, "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"); strcpy((char*)data, "The quick brown fox jumps over the lazy dog"); len = strlen((char*)data); b64 = SHA256_Data(data, len, b64digest); CuAssertPtrNotNull(tc, b64); len = strlen((char*)b64); sh_util_base64_dec (data, (unsigned char*)b64, len); d = data; buffer = hexdigest; for (i = 0; i < SHA256_DIGEST_LENGTH; i++) { *buffer++ = sha2_hex_digits[(*d & 0xf0) >> 4]; *buffer++ = sha2_hex_digits[*d & 0x0f]; d++; } *buffer = (char)0; CuAssertStrEquals(tc, hexdigest, "d7a8fbb307d7809469ca9abcb0082e4f8d5651e46d3cdb762d02d0bf37c9e592"); strcpy((char*)data, "The quick brown fox jumps over the lazy dog."); len = strlen((char*)data); b64 = SHA256_Data(data, len, b64digest); CuAssertPtrNotNull(tc, b64); len = strlen((char*)b64); sh_util_base64_dec (data, (unsigned char*)b64, len); d = data; buffer = hexdigest; for (i = 0; i < SHA256_DIGEST_LENGTH; i++) { *buffer++ = sha2_hex_digits[(*d & 0xf0) >> 4]; *buffer++ = sha2_hex_digits[*d & 0x0f]; d++; } *buffer = (char)0; CuAssertStrEquals(tc, hexdigest, "ef537f25c895bfa782526529a9b63d97aa631564d5d789c2b765448c8635fb6c"); } #endif