/* This code is from rfc1186. It has been modified to use the SIVAL() macro to make it byte order and length independent, so we don't need the LOWBYTEFIRST define */ /* ** ******************************************************************** ** md4.c -- Implementation of MD4 Message Digest Algorithm ** ** Updated: 2/16/90 by Ronald L. Rivest ** ** (C) 1990 RSA Data Security, Inc. ** ** ******************************************************************** */ /* ** To use MD4: ** -- Include md4.h in your program ** -- Declare an MDstruct MD to hold the state of the digest ** computation. ** -- Initialize MD using MDbegin(&MD) ** -- For each full block (64 bytes) X you wish to process, call ** MDupdate(&MD,X,512) ** (512 is the number of bits in a full block.) ** -- For the last block (less than 64 bytes) you wish to process, ** MDupdate(&MD,X,n) ** where n is the number of bits in the partial block. A partial ** block terminates the computation, so every MD computation ** should terminate by processing a partial block, even if it ** has n = 0. ** -- The message digest is available in MD.buffer[0] ... ** MD.buffer[3]. (Least-significant byte of each word ** should be output first.) ** -- You can print out the digest using MDprint(&MD) */ #define TRUE 1 #define FALSE 0 /* Compile-time includes */ #include "rsync.h" /* Compile-time declarations of MD4 "magic constants". */ #define I0 0x67452301 /* Initial values for MD buffer */ #define I1 0xefcdab89 #define I2 0x98badcfe #define I3 0x10325476 #define C2 013240474631 /* round 2 constant = sqrt(2) in octal */ #define C3 015666365641 /* round 3 constant = sqrt(3) in octal */ /* C2 and C3 are from Knuth, The Art of Programming, Volume 2 ** (Seminumerical Algorithms), Second Edition (1981), Addison-Wesley. ** Table 2, page 660. */ #define fs1 3 /* round 1 shift amounts */ #define fs2 7 #define fs3 11 #define fs4 19 #define gs1 3 /* round 2 shift amounts */ #define gs2 5 #define gs3 9 #define gs4 13 #define hs1 3 /* round 3 shift amounts */ #define hs2 9 #define hs3 11 #define hs4 15 /* Compile-time macro declarations for MD4. ** Note: The "rot" operator uses the variable "tmp". ** It assumes tmp is declared as unsigned int, so that the >> ** operator will shift in zeros rather than extending the sign bit. */ #define f(X,Y,Z) ((X&Y) | ((~X)&Z)) #define g(X,Y,Z) ((X&Y) | (X&Z) | (Y&Z)) #define h(X,Y,Z) (X^Y^Z) #define rot(X,S) (tmp=X,(tmp<>(32-S))) #define ff(A,B,C,D,i,s) A = rot((A + f(B,C,D) + X[i]),s) #define gg(A,B,C,D,i,s) A = rot((A + g(B,C,D) + X[i] + C2),s) #define hh(A,B,C,D,i,s) A = rot((A + h(B,C,D) + X[i] + C3),s) /* MDbegin(MDp) ** Initialize message digest buffer MDp. ** This is a user-callable routine. */ void MDbegin(MDp) MDptr MDp; { int i; MDp->buffer[0] = I0; MDp->buffer[1] = I1; MDp->buffer[2] = I2; MDp->buffer[3] = I3; for (i=0;i<8;i++) MDp->count[i] = 0; MDp->done = 0; } /* MDreverse(X) ** Reverse the byte-ordering of every int in X. ** Assumes X is an array of 16 ints. ** The macro revx reverses the byte-ordering of the next word of X. */ void MDreverse(X) unsigned int32 *X; { register unsigned int32 t; register unsigned int i; for(i = 0; i < 16; i++) { t = X[i]; SIVAL(X,i*4,t); } } /* MDblock(MDp,X) ** Update message digest buffer MDp->buffer using 16-word data block X. ** Assumes all 16 words of X are full of data. ** Does not update MDp->count. ** This routine is not user-callable. */ static void MDblock(MDp,X) MDptr MDp; unsigned int32 *X; { register unsigned int32 tmp, A, B, C, D; MDreverse(X); A = MDp->buffer[0]; B = MDp->buffer[1]; C = MDp->buffer[2]; D = MDp->buffer[3]; /* Update the message digest buffer */ ff(A , B , C , D , 0 , fs1); /* Round 1 */ ff(D , A , B , C , 1 , fs2); ff(C , D , A , B , 2 , fs3); ff(B , C , D , A , 3 , fs4); ff(A , B , C , D , 4 , fs1); ff(D , A , B , C , 5 , fs2); ff(C , D , A , B , 6 , fs3); ff(B , C , D , A , 7 , fs4); ff(A , B , C , D , 8 , fs1); ff(D , A , B , C , 9 , fs2); ff(C , D , A , B , 10 , fs3); ff(B , C , D , A , 11 , fs4); ff(A , B , C , D , 12 , fs1); ff(D , A , B , C , 13 , fs2); ff(C , D , A , B , 14 , fs3); ff(B , C , D , A , 15 , fs4); gg(A , B , C , D , 0 , gs1); /* Round 2 */ gg(D , A , B , C , 4 , gs2); gg(C , D , A , B , 8 , gs3); gg(B , C , D , A , 12 , gs4); gg(A , B , C , D , 1 , gs1); gg(D , A , B , C , 5 , gs2); gg(C , D , A , B , 9 , gs3); gg(B , C , D , A , 13 , gs4); gg(A , B , C , D , 2 , gs1); gg(D , A , B , C , 6 , gs2); gg(C , D , A , B , 10 , gs3); gg(B , C , D , A , 14 , gs4); gg(A , B , C , D , 3 , gs1); gg(D , A , B , C , 7 , gs2); gg(C , D , A , B , 11 , gs3); gg(B , C , D , A , 15 , gs4); hh(A , B , C , D , 0 , hs1); /* Round 3 */ hh(D , A , B , C , 8 , hs2); hh(C , D , A , B , 4 , hs3); hh(B , C , D , A , 12 , hs4); hh(A , B , C , D , 2 , hs1); hh(D , A , B , C , 10 , hs2); hh(C , D , A , B , 6 , hs3); hh(B , C , D , A , 14 , hs4); hh(A , B , C , D , 1 , hs1); hh(D , A , B , C , 9 , hs2); hh(C , D , A , B , 5 , hs3); hh(B , C , D , A , 13 , hs4); hh(A , B , C , D , 3 , hs1); hh(D , A , B , C , 11 , hs2); hh(C , D , A , B , 7 , hs3); hh(B , C , D , A , 15 , hs4); MDp->buffer[0] += A; MDp->buffer[1] += B; MDp->buffer[2] += C; MDp->buffer[3] += D; } /* MDupdate(MDp,X,count) ** Input: MDp -- an MDptr ** X -- a pointer to an array of unsigned characters. ** count -- the number of bits of X to use. ** (if not a multiple of 8, uses high bits of last byte.) ** Update MDp using the number of bits of X given by count. ** This is the basic input routine for an MD4 user. ** The routine completes the MD computation when count < 512, so ** every MD computation should end with one call to MDupdate with a ** count less than 512. A call with count 0 will be ignored if the ** MD has already been terminated (done != 0), so an extra call with ** count 0 can be given as a "courtesy close" to force termination ** if desired. */ void MDupdate(MDp,X,count) MDptr MDp; unsigned char *X; unsigned int count; { unsigned int32 i, tmp, bit, byte, mask; unsigned char XX[64]; unsigned char *p; /* return with no error if this is a courtesy close with count ** zero and MDp->done is true. */ if (count == 0 && MDp->done) return; /* check to see if MD is already done and report error */ if (MDp->done) { rprintf(FERROR,"\nError: MDupdate MD already done."); return; } /* Add count to MDp->count */ tmp = count; p = MDp->count; while (tmp) { tmp += *p; *p++ = tmp; tmp = tmp >> 8; } /* Process data */ if (count == 512) { /* Full block of data to handle */ MDblock(MDp,(unsigned int *)X); } else if (count > 512) /* Check for count too large */ { rprintf(FERROR,"\nError: MDupdate called with illegal count value %d." ,count); return; } else /* partial block -- must be last block so finish up */ { /* Find out how many bytes and residual bits there are */ byte = count >> 3; bit = count & 7; /* Copy X into XX since we need to modify it */ for (i=0;i<=byte;i++) XX[i] = X[i]; for (i=byte+1;i<64;i++) XX[i] = 0; /* Add padding '1' bit and low-order zeros in last byte */ mask = 1 << (7 - bit); XX[byte] = (XX[byte] | mask) & ~( mask - 1); /* If room for bit count, finish up with this block */ if (byte <= 55) { for (i=0;i<8;i++) XX[56+i] = MDp->count[i]; MDblock(MDp,(unsigned int32 *)XX); } else /* need to do two blocks to finish up */ { MDblock(MDp,(unsigned int32 *)XX); for (i=0;i<56;i++) XX[i] = 0; for (i=0;i<8;i++) XX[56+i] = MDp->count[i]; MDblock(MDp,(unsigned int32 *)XX); } /* Set flag saying we're done with MD computation */ MDp->done = 1; } } /* ** End of md4.c */