/* SHA-1 in C By Steve Reid 100% Public Domain ----------------- Modified 7/98 By James H. Brown Still 100% Public Domain Corrected a problem which generated improper hash values on 16 bit machines Routine SHA1Update changed from void SHA1Update(SHA1_CTX* context, unsigned char* data, unsigned int len) to void SHA1Update(SHA1_CTX* context, unsigned char* data, unsigned long len) The 'len' parameter was declared an int which works fine on 32 bit machines. However, on 16 bit machines an int is too small for the shifts being done against it. This caused the hash function to generate incorrect values if len was greater than 8191 (8K - 1) due to the 'len << 3' on line 3 of SHA1Update(). Since the file IO in main() reads 16K at a time, any file 8K or larger would be guaranteed to generate the wrong hash (e.g. Test Vector #3, a million "a"s). I also changed the declaration of variables i & j in SHA1Update to unsigned long from unsigned int for the same reason. These changes should make no difference to any 32 bit implementations since an int and a long are the same size in those environments. -- I also corrected a few compiler warnings generated by Borland C. 1. Added #include for exit() prototype 2. Removed unused variable 'j' in SHA1Final 3. Changed exit(0) to return(0) at end of main. ALL changes I made can be located by searching for comments containing 'JHB' ----------------- Modified 8/98 By Steve Reid Still 100% public domain 1- Removed #include and used return() instead of exit() 2- Fixed overwriting of finalcount in SHA1Final() (discovered by Chris Hall) 3- Changed email address from steve@edmweb.com to sreid@sea-to-sky.net ----------------- Modified 4/01 By Saul Kravitz Still 100% PD Modified to run on Compaq Alpha hardware. ----------------- Modified 07/2002 By Ralph Giles Still 100% public domain modified for use with stdint types, autoconf code cleanup, removed attribution comments switched SHA1Final() argument order for consistency use SHA1_ prefix for public api move public api to sha1.h ----------------- Modified 07/2002 By Ralph Giles Still 100% public domain ----------------- Modified 12/2011 By Jonathan Worthington Still 100% public domain Strip out various test code, twiddle digest to ASCII code a bit. */ #include #include #include "sha1.h" void SHA1_Transform(unsigned int state[5], const unsigned char buffer[64]); #define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits)))) /* blk0() and blk() perform the initial expand. */ /* I got the idea of expanding during the round function from SSLeay */ /* FIXME: can we do this in an endian-proof way? */ #ifdef WORDS_BIGENDIAN #define blk0(i) block->l[i] #else #define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) \ |(rol(block->l[i],8)&0x00FF00FF)) #endif #define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \ ^block->l[(i+2)&15]^block->l[i&15],1)) /* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */ #define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30); #define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30); #define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30); #define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30); #define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30); /* Hash a single 512-bit block. This is the core of the algorithm. */ void SHA1_Transform(unsigned int state[5], const unsigned char buffer[64]) { unsigned int a, b, c, d, e; typedef union { unsigned char c[64]; unsigned int l[16]; } CHAR64LONG16; CHAR64LONG16* block; block = (CHAR64LONG16*)buffer; /* Copy context->state[] to working vars */ a = state[0]; b = state[1]; c = state[2]; d = state[3]; e = state[4]; /* 4 rounds of 20 operations each. Loop unrolled. */ R0(a,b,c,d,e, 0); R0(e,a,b,c,d, 1); R0(d,e,a,b,c, 2); R0(c,d,e,a,b, 3); R0(b,c,d,e,a, 4); R0(a,b,c,d,e, 5); R0(e,a,b,c,d, 6); R0(d,e,a,b,c, 7); R0(c,d,e,a,b, 8); R0(b,c,d,e,a, 9); R0(a,b,c,d,e,10); R0(e,a,b,c,d,11); R0(d,e,a,b,c,12); R0(c,d,e,a,b,13); R0(b,c,d,e,a,14); R0(a,b,c,d,e,15); R1(e,a,b,c,d,16); R1(d,e,a,b,c,17); R1(c,d,e,a,b,18); R1(b,c,d,e,a,19); R2(a,b,c,d,e,20); R2(e,a,b,c,d,21); R2(d,e,a,b,c,22); R2(c,d,e,a,b,23); R2(b,c,d,e,a,24); R2(a,b,c,d,e,25); R2(e,a,b,c,d,26); R2(d,e,a,b,c,27); R2(c,d,e,a,b,28); R2(b,c,d,e,a,29); R2(a,b,c,d,e,30); R2(e,a,b,c,d,31); R2(d,e,a,b,c,32); R2(c,d,e,a,b,33); R2(b,c,d,e,a,34); R2(a,b,c,d,e,35); R2(e,a,b,c,d,36); R2(d,e,a,b,c,37); R2(c,d,e,a,b,38); R2(b,c,d,e,a,39); R3(a,b,c,d,e,40); R3(e,a,b,c,d,41); R3(d,e,a,b,c,42); R3(c,d,e,a,b,43); R3(b,c,d,e,a,44); R3(a,b,c,d,e,45); R3(e,a,b,c,d,46); R3(d,e,a,b,c,47); R3(c,d,e,a,b,48); R3(b,c,d,e,a,49); R3(a,b,c,d,e,50); R3(e,a,b,c,d,51); R3(d,e,a,b,c,52); R3(c,d,e,a,b,53); R3(b,c,d,e,a,54); R3(a,b,c,d,e,55); R3(e,a,b,c,d,56); R3(d,e,a,b,c,57); R3(c,d,e,a,b,58); R3(b,c,d,e,a,59); R4(a,b,c,d,e,60); R4(e,a,b,c,d,61); R4(d,e,a,b,c,62); R4(c,d,e,a,b,63); R4(b,c,d,e,a,64); R4(a,b,c,d,e,65); R4(e,a,b,c,d,66); R4(d,e,a,b,c,67); R4(c,d,e,a,b,68); R4(b,c,d,e,a,69); R4(a,b,c,d,e,70); R4(e,a,b,c,d,71); R4(d,e,a,b,c,72); R4(c,d,e,a,b,73); R4(b,c,d,e,a,74); R4(a,b,c,d,e,75); R4(e,a,b,c,d,76); R4(d,e,a,b,c,77); R4(c,d,e,a,b,78); R4(b,c,d,e,a,79); /* Add the working vars back into context.state[] */ state[0] += a; state[1] += b; state[2] += c; state[3] += d; state[4] += e; /* Wipe variables */ a = b = c = d = e = 0; } /* SHA1Init - Initialize new context */ void SHA1Init(SHA1Context* context) { /* SHA1 initialization constants */ context->state[0] = 0x67452301; context->state[1] = 0xEFCDAB89; context->state[2] = 0x98BADCFE; context->state[3] = 0x10325476; context->state[4] = 0xC3D2E1F0; context->count[0] = context->count[1] = 0; } /* Run your data through this. */ void SHA1Update(SHA1Context* context, const unsigned char* data, const size_t len) { size_t i, j; j = (context->count[0] >> 3) & 63; if ((context->count[0] += len << 3) < (len << 3)) context->count[1]++; context->count[1] += (len >> 29); if ((j + len) > 63) { memcpy(&context->buffer[j], data, (i = 64-j)); SHA1_Transform(context->state, context->buffer); for ( ; i + 63 < len; i += 64) { SHA1_Transform(context->state, data + i); } j = 0; } else i = 0; memcpy(&context->buffer[j], &data[i], len - i); } /* Add padding and return the message digest. */ void SHA1_Digest(SHA1Context* context, unsigned char digest[SHA1_DIGEST_SIZE]) { unsigned int i; unsigned char finalcount[8]; for (i = 0; i < 8; i++) { finalcount[i] = (unsigned char)((context->count[(i >= 4 ? 0 : 1)] >> ((3-(i & 3)) * 8) ) & 255); /* Endian independent */ } SHA1Update(context, (unsigned char *)"\200", 1); while ((context->count[0] & 504) != 448) { SHA1Update(context, (unsigned char *)"\0", 1); } SHA1Update(context, finalcount, 8); /* Should cause a SHA1_Transform() */ for (i = 0; i < SHA1_DIGEST_SIZE; i++) { digest[i] = (unsigned char) ((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255); } /* Wipe variables */ i = 0; memset(context->buffer, 0, 64); memset(context->state, 0, 20); memset(context->count, 0, 8); memset(finalcount, 0, 8); /* SWR */ } /* Produces a hex output of the digest. */ void SHA1Final(SHA1Context *context, char *output) { unsigned char digest[20]; int i; char *c = output; SHA1_Digest(context, digest); unsigned char *d = digest; const char *hex = "0123456789ABCDEF"; for (i = 0; i < 20; i++) { *c++ = hex[(*d >> 4) & 0xF]; *c++ = hex[(*d++) & 0xF]; } *c = 0; }