/* This file is part of libextractor. (C) 2004, 2005 Vidyut Samanta and Christian Grothoff Copyright (C) 1995, 1996, 1999, 2000, 2003 Free Software Foundation, Inc. NOTE: The canonical source of the MD5 code from this file is maintained with the GNU C Library. Bugs can be reported to bug-glibc@prep.ai.mit.edu. libextractor 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, or (at your option) any later version. libextractor 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 libextractor; see the file COPYING. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include "platform.h" #include "extractor.h" #include #include #ifdef _LIBC #include typedef uint32_t md5_uint32; typedef uintptr_t md5_uintptr; #else # define UINT_MAX_32_BITS 4294967295U # if UINT_MAX == UINT_MAX_32_BITS typedef unsigned int md5_uint32; # else # if USHRT_MAX == UINT_MAX_32_BITS typedef unsigned short md5_uint32; # else # if ULONG_MAX == UINT_MAX_32_BITS typedef unsigned long md5_uint32; # else /* The following line is intended to evoke an error. Using #error is not portable enough. */ "Cannot determine unsigned 32-bit data type." # endif # endif # endif /* We have to make a guess about the integer type equivalent in size to pointers which should always be correct. */ typedef unsigned long int md5_uintptr; #endif /* Structure to save state of computation between the single steps. */ struct md5_ctx { md5_uint32 A; md5_uint32 B; md5_uint32 C; md5_uint32 D; md5_uint32 total[2]; md5_uint32 buflen; char buffer[128]; }; #define rol(x,n) ( ((x) << (n)) | ((x) >> (32-(n))) ) #if __BYTE_ORDER == __BIG_ENDIAN #define WORDS_BIGENDIAN 1 #endif #ifdef WORDS_BIGENDIAN # define SWAP(n) \ (((n) << 24) | (((n) & 0xff00) << 8) | (((n) >> 8) & 0xff00) | ((n) >> 24)) #else # define SWAP(n) (n) #endif #define BLOCKSIZE 4096 /* Ensure that BLOCKSIZE is a multiple of 64. */ #if BLOCKSIZE % 64 != 0 #error "invalid BLOCKSIZE" #endif /* This array contains the bytes used to pad the buffer to the next 64-byte boundary. (RFC 1321, 3.1: Step 1) */ static const unsigned char fillbuf[64] = { 0x80, 0 /* , 0, 0, ... */ }; /* These are the four functions used in the four steps of the MD5 algorithm and defined in the RFC 1321. The first function is a little bit optimized (as found in Colin Plumbs public domain implementation). */ /* #define FF(b, c, d) ((b & c) | (~b & d)) */ #define FF(b, c, d) (d ^ (b & (c ^ d))) #define FG(b, c, d) FF (d, b, c) #define FH(b, c, d) (b ^ c ^ d) #define FI(b, c, d) (c ^ (b | ~d)) /* Process LEN bytes of BUFFER, accumulating context into CTX. It is assumed that LEN % 64 == 0. */ static void md5_process_block (const void *buffer, size_t len, struct md5_ctx *ctx) { md5_uint32 correct_words[16]; const md5_uint32 *words = buffer; size_t nwords = len / sizeof (md5_uint32); const md5_uint32 *endp = words + nwords; md5_uint32 A = ctx->A; md5_uint32 B = ctx->B; md5_uint32 C = ctx->C; md5_uint32 D = ctx->D; /* First increment the byte count. RFC 1321 specifies the possible length of the file up to 2^64 bits. Here we only compute the number of bytes. Do a double word increment. */ ctx->total[0] += len; if (ctx->total[0] < len) ++ctx->total[1]; /* Process all bytes in the buffer with 64 bytes in each round of the loop. */ while (words < endp) { md5_uint32 *cwp = correct_words; md5_uint32 A_save = A; md5_uint32 B_save = B; md5_uint32 C_save = C; md5_uint32 D_save = D; /* First round: using the given function, the context and a constant the next context is computed. Because the algorithms processing unit is a 32-bit word and it is determined to work on words in little endian byte order we perhaps have to change the byte order before the computation. To reduce the work for the next steps we store the swapped words in the array CORRECT_WORDS. */ #define OP(a, b, c, d, s, T) \ do \ { \ a += FF (b, c, d) + (*cwp++ = SWAP (*words)) + T; \ ++words; \ a = rol (a, s); \ a += b; \ } \ while (0) /* Before we start, one word to the strange constants. They are defined in RFC 1321 as T[i] = (int) (4294967296.0 * fabs (sin (i))), i=1..64, or perl -e 'foreach(1..64){printf "0x%08x\n", int (4294967296 * abs (sin $_))}' */ /* Round 1. */ OP (A, B, C, D, 7, 0xd76aa478); OP (D, A, B, C, 12, 0xe8c7b756); OP (C, D, A, B, 17, 0x242070db); OP (B, C, D, A, 22, 0xc1bdceee); OP (A, B, C, D, 7, 0xf57c0faf); OP (D, A, B, C, 12, 0x4787c62a); OP (C, D, A, B, 17, 0xa8304613); OP (B, C, D, A, 22, 0xfd469501); OP (A, B, C, D, 7, 0x698098d8); OP (D, A, B, C, 12, 0x8b44f7af); OP (C, D, A, B, 17, 0xffff5bb1); OP (B, C, D, A, 22, 0x895cd7be); OP (A, B, C, D, 7, 0x6b901122); OP (D, A, B, C, 12, 0xfd987193); OP (C, D, A, B, 17, 0xa679438e); OP (B, C, D, A, 22, 0x49b40821); /* For the second to fourth round we have the possibly swapped words in CORRECT_WORDS. Redefine the macro to take an additional first argument specifying the function to use. */ #undef OP #define OP(f, a, b, c, d, k, s, T) \ do \ { \ a += f (b, c, d) + correct_words[k] + T; \ a = rol (a, s); \ a += b; \ } \ while (0) /* Round 2. */ OP (FG, A, B, C, D, 1, 5, 0xf61e2562); OP (FG, D, A, B, C, 6, 9, 0xc040b340); OP (FG, C, D, A, B, 11, 14, 0x265e5a51); OP (FG, B, C, D, A, 0, 20, 0xe9b6c7aa); OP (FG, A, B, C, D, 5, 5, 0xd62f105d); OP (FG, D, A, B, C, 10, 9, 0x02441453); OP (FG, C, D, A, B, 15, 14, 0xd8a1e681); OP (FG, B, C, D, A, 4, 20, 0xe7d3fbc8); OP (FG, A, B, C, D, 9, 5, 0x21e1cde6); OP (FG, D, A, B, C, 14, 9, 0xc33707d6); OP (FG, C, D, A, B, 3, 14, 0xf4d50d87); OP (FG, B, C, D, A, 8, 20, 0x455a14ed); OP (FG, A, B, C, D, 13, 5, 0xa9e3e905); OP (FG, D, A, B, C, 2, 9, 0xfcefa3f8); OP (FG, C, D, A, B, 7, 14, 0x676f02d9); OP (FG, B, C, D, A, 12, 20, 0x8d2a4c8a); /* Round 3. */ OP (FH, A, B, C, D, 5, 4, 0xfffa3942); OP (FH, D, A, B, C, 8, 11, 0x8771f681); OP (FH, C, D, A, B, 11, 16, 0x6d9d6122); OP (FH, B, C, D, A, 14, 23, 0xfde5380c); OP (FH, A, B, C, D, 1, 4, 0xa4beea44); OP (FH, D, A, B, C, 4, 11, 0x4bdecfa9); OP (FH, C, D, A, B, 7, 16, 0xf6bb4b60); OP (FH, B, C, D, A, 10, 23, 0xbebfbc70); OP (FH, A, B, C, D, 13, 4, 0x289b7ec6); OP (FH, D, A, B, C, 0, 11, 0xeaa127fa); OP (FH, C, D, A, B, 3, 16, 0xd4ef3085); OP (FH, B, C, D, A, 6, 23, 0x04881d05); OP (FH, A, B, C, D, 9, 4, 0xd9d4d039); OP (FH, D, A, B, C, 12, 11, 0xe6db99e5); OP (FH, C, D, A, B, 15, 16, 0x1fa27cf8); OP (FH, B, C, D, A, 2, 23, 0xc4ac5665); /* Round 4. */ OP (FI, A, B, C, D, 0, 6, 0xf4292244); OP (FI, D, A, B, C, 7, 10, 0x432aff97); OP (FI, C, D, A, B, 14, 15, 0xab9423a7); OP (FI, B, C, D, A, 5, 21, 0xfc93a039); OP (FI, A, B, C, D, 12, 6, 0x655b59c3); OP (FI, D, A, B, C, 3, 10, 0x8f0ccc92); OP (FI, C, D, A, B, 10, 15, 0xffeff47d); OP (FI, B, C, D, A, 1, 21, 0x85845dd1); OP (FI, A, B, C, D, 8, 6, 0x6fa87e4f); OP (FI, D, A, B, C, 15, 10, 0xfe2ce6e0); OP (FI, C, D, A, B, 6, 15, 0xa3014314); OP (FI, B, C, D, A, 13, 21, 0x4e0811a1); OP (FI, A, B, C, D, 4, 6, 0xf7537e82); OP (FI, D, A, B, C, 11, 10, 0xbd3af235); OP (FI, C, D, A, B, 2, 15, 0x2ad7d2bb); OP (FI, B, C, D, A, 9, 21, 0xeb86d391); /* Add the starting values of the context. */ A += A_save; B += B_save; C += C_save; D += D_save; } /* Put checksum in context given as argument. */ ctx->A = A; ctx->B = B; ctx->C = C; ctx->D = D; } static void md5_process_bytes (const void *buffer, size_t len, struct md5_ctx *ctx) { /* When we already have some bits in our internal buffer concatenate both inputs first. */ if (ctx->buflen != 0) { size_t left_over = ctx->buflen; size_t add = 128 - left_over > len ? len : 128 - left_over; memcpy (&ctx->buffer[left_over], buffer, add); ctx->buflen += add; if (ctx->buflen > 64) { md5_process_block (ctx->buffer, ctx->buflen & ~63, ctx); ctx->buflen &= 63; /* The regions in the following copy operation cannot overlap. */ memcpy (ctx->buffer, &ctx->buffer[(left_over + add) & ~63], ctx->buflen); } buffer = (const char *) buffer + add; len -= add; } /* Process available complete blocks. */ if (len >= 64) { #if !_STRING_ARCH_unaligned /* To check alignment gcc has an appropriate operator. Other compilers don't. */ # if __GNUC__ >= 2 # define UNALIGNED_P(p) (((md5_uintptr) p) % __alignof__ (md5_uint32) != 0) # else # define UNALIGNED_P(p) (((md5_uintptr) p) % sizeof (md5_uint32) != 0) # endif if (UNALIGNED_P (buffer)) while (len > 64) { md5_process_block (memcpy (ctx->buffer, buffer, 64), 64, ctx); buffer = (const char *) buffer + 64; len -= 64; } else #endif { md5_process_block (buffer, len & ~63, ctx); buffer = (const char *) buffer + (len & ~63); len &= 63; } } /* Move remaining bytes in internal buffer. */ if (len > 0) { size_t left_over = ctx->buflen; memcpy (&ctx->buffer[left_over], buffer, len); left_over += len; if (left_over >= 64) { md5_process_block (ctx->buffer, 64, ctx); left_over -= 64; memcpy (ctx->buffer, &ctx->buffer[64], left_over); } ctx->buflen = left_over; } } /* Initialize structure containing state of computation. (RFC 1321, 3.3: Step 3) */ static void md5_init_ctx (struct md5_ctx *ctx) { ctx->A = 0x67452301; ctx->B = 0xefcdab89; ctx->C = 0x98badcfe; ctx->D = 0x10325476; ctx->total[0] = ctx->total[1] = 0; ctx->buflen = 0; } /* Put result from CTX in first 16 bytes following RESBUF. The result must be in little endian byte order. IMPORTANT: On some systems it is required that RESBUF is correctly aligned for a 32 bits value. */ static void * md5_read_ctx (const struct md5_ctx *ctx, void *resbuf) { ((md5_uint32 *) resbuf)[0] = SWAP (ctx->A); ((md5_uint32 *) resbuf)[1] = SWAP (ctx->B); ((md5_uint32 *) resbuf)[2] = SWAP (ctx->C); ((md5_uint32 *) resbuf)[3] = SWAP (ctx->D); return resbuf; } /* Process the remaining bytes in the internal buffer and the usual prolog according to the standard and write the result to RESBUF. IMPORTANT: On some systems it is required that RESBUF is correctly aligned for a 32 bits value. */ static void * md5_finish_ctx (struct md5_ctx *ctx, void *resbuf) { /* Take yet unprocessed bytes into account. */ md5_uint32 bytes = ctx->buflen; size_t pad; /* Now count remaining bytes. */ ctx->total[0] += bytes; if (ctx->total[0] < bytes) ++ctx->total[1]; pad = bytes >= 56 ? 64 + 56 - bytes : 56 - bytes; memcpy (&ctx->buffer[bytes], fillbuf, pad); /* Put the 64-bit file length in *bits* at the end of the buffer. */ *(md5_uint32 *) &ctx->buffer[bytes + pad] = SWAP (ctx->total[0] << 3); *(md5_uint32 *) &ctx->buffer[bytes + pad + 4] = SWAP ((ctx->total[1] << 3) | (ctx->total[0] >> 29)); /* Process last bytes. */ md5_process_block (ctx->buffer, bytes + pad + 8, ctx); return md5_read_ctx (ctx, resbuf); } /* Compute MD5 message digest for LEN bytes beginning at BUFFER. The result is always in little endian byte order, so that a byte-wise output yields to the wanted ASCII representation of the message digest. */ static void * md5_buffer (const char *buffer, size_t len, void *resblock) { struct md5_ctx ctx; /* Initialize the computation context. */ md5_init_ctx (&ctx); /* Process whole buffer but last len % 64 bytes. */ md5_process_bytes (buffer, len, &ctx); /* Put result in desired memory area. */ return md5_finish_ctx (&ctx, resblock); } static struct EXTRACTOR_Keywords * addKeyword(EXTRACTOR_KeywordList *oldhead, const char *phrase, EXTRACTOR_KeywordType type) { EXTRACTOR_KeywordList * keyword; keyword = (EXTRACTOR_KeywordList*) malloc(sizeof(EXTRACTOR_KeywordList)); keyword->next = oldhead; keyword->keyword = strdup(phrase); keyword->keywordType = type; return keyword; } #define DIGEST_BITS 128 #define DIGEST_HEX_BYTES (DIGEST_BITS / 4) #define DIGEST_BIN_BYTES (DIGEST_BITS / 8) #define MAX_DIGEST_BIN_BYTES DIGEST_BIN_BYTES struct EXTRACTOR_Keywords * libextractor_hash_md5_extract(const char * filename, const char * data, size_t size, struct EXTRACTOR_Keywords * prev) { unsigned char bin_buffer[MAX_DIGEST_BIN_BYTES]; char hash[8 * MAX_DIGEST_BIN_BYTES]; char buf[16]; int i; md5_buffer(data, size, bin_buffer); hash[0] = '\0'; for (i=0;i