/*
* ** **************************************************************************
* ** md5.c -- Implementation of MD5 Message Digest Algorithm **
* ** Updated: 2/16/90 by Ronald L. Rivest **
* ** (C) 1990 RSA Data Security, Inc. **
* ** **************************************************************************
*/
/*
* ** To use MD5:
* ** -- Include md5.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)
*/
/*
* Implementation notes:
* ** This implementation assumes that ints are 32-bit quantities.
* ** If the machine stores the least-significant byte of an int in the
* ** least-addressed byte (eg., VAX and 8086), then LOWBYTEFIRST should be
* ** set to TRUE. Otherwise (eg., SUNS), LOWBYTEFIRST should be set to
* ** FALSE. Note that on machines with LOWBYTEFIRST FALSE the routine
* ** MDupdate modifies has a side-effect on its input array (the order of bytes
* ** in each word are reversed). If this is undesired a call to MDreverse(X) can
* ** reverse the bytes of X back into order after each call to MDupdate.
*/
/*
* code uses WORDS_BIGENDIAN defined by configure now -- WH 9/27/95
*/
/*
* Compile-time includes
*/
#include <net-snmp/net-snmp-config.h>
#ifndef NETSNMP_DISABLE_MD5
#include <stdio.h>
#include <sys/types.h>
#if HAVE_STRING_H
#include <string.h>
#else
#include <strings.h>
#endif
#if HAVE_STDLIB_H
#include <stdlib.h>
#endif
#include <net-snmp/net-snmp-includes.h>
#include <net-snmp/utilities.h>
#include <net-snmp/library/md5.h>
/*
* Compile-time declarations of MD5 ``magic constants''.
*/
#define I0 0x67452301 /* Initial values for MD buffer */
#define I1 0xefcdab89
#define I2 0x98badcfe
#define I3 0x10325476
#define fs1 7 /* round 1 shift amounts */
#define fs2 12
#define fs3 17
#define fs4 22
#define gs1 5 /* round 2 shift amounts */
#define gs2 9
#define gs3 14
#define gs4 20
#define hs1 4 /* round 3 shift amounts */
#define hs2 11
#define hs3 16
#define hs4 23
#define is1 6 /* round 4 shift amounts */
#define is2 10
#define is3 15
#define is4 21
/*
* Compile-time macro declarations for MD5.
* ** 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&Z) | (Y&(~Z)))
#define h(X,Y,Z) (X^Y^Z)
#define i_(X,Y,Z) (Y ^ ((X) | (~Z)))
#define rot(X,S) (tmp=X,(tmp<<S) | (tmp>>(32-S)))
#define ff(A,B,C,D,i,s,lp) A = rot((A + f(B,C,D) + X[i] + lp),s) + B
#define gg(A,B,C,D,i,s,lp) A = rot((A + g(B,C,D) + X[i] + lp),s) + B
#define hh(A,B,C,D,i,s,lp) A = rot((A + h(B,C,D) + X[i] + lp),s) + B
#define ii(A,B,C,D,i,s,lp) A = rot((A + i_(B,C,D) + X[i] + lp),s) + B
#ifdef STDC_HEADERS
#define Uns(num) num##U
#else
#define Uns(num) num
#endif /* STDC_HEADERS */
void MDreverse(unsigned int *);
static void MDblock(MDptr, const unsigned int *);
#ifdef NETSNMP_ENABLE_TESTING_CODE
/*
* MDprint(MDp)
* ** Print message digest buffer MDp as 32 hexadecimal digits.
* ** Order is from low-order byte of buffer[0] to high-order byte of buffer[3].
* ** Each byte is printed with high-order hexadecimal digit first.
* ** This is a user-callable routine.
*/
void
MDprint(MDptr MDp)
{
int i, j;
for (i = 0; i < 4; i++)
for (j = 0; j < 32; j = j + 8)
printf("%02x", (MDp->buffer[i] >> j) & 0xFF);
printf("\n");
fflush(stdout);
}
#endif /* NETSNMP_ENABLE_TESTING_CODE */
/*
* MDbegin(MDp)
* ** Initialize message digest buffer MDp.
* ** This is a user-callable routine.
*/
void
MDbegin(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.
*/
#define revx { t = (*X << 16) | (*X >> 16); \
*X++ = ((t & 0xFF00FF00) >> 8) | ((t & 0x00FF00FF) << 8); }
void
MDreverse(unsigned int *X)
{
register unsigned int t;
revx;
revx;
revx;
revx;
revx;
revx;
revx;
revx;
revx;
revx;
revx;
revx;
revx;
revx;
revx;
revx;
}
/*
* 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(MDptr MDp, const unsigned int *X)
{
register unsigned int tmp, A, B, C, D; /* hpux sysv sun */
#ifdef WORDS_BIGENDIAN
MDreverse(X);
#endif
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, Uns(3614090360)); /* Round 1 */
ff(D, A, B, C, 1, fs2, Uns(3905402710));
ff(C, D, A, B, 2, fs3, Uns(606105819));
ff(B, C, D, A, 3, fs4, Uns(3250441966));
ff(A, B, C, D, 4, fs1, Uns(4118548399));
ff(D, A, B, C, 5, fs2, Uns(1200080426));
ff(C, D, A, B, 6, fs3, Uns(2821735955));
ff(B, C, D, A, 7, fs4, Uns(4249261313));
ff(A, B, C, D, 8, fs1, Uns(1770035416));
ff(D, A, B, C, 9, fs2, Uns(2336552879));
ff(C, D, A, B, 10, fs3, Uns(4294925233));
ff(B, C, D, A, 11, fs4, Uns(2304563134));
ff(A, B, C, D, 12, fs1, Uns(1804603682));
ff(D, A, B, C, 13, fs2, Uns(4254626195));
ff(C, D, A, B, 14, fs3, Uns(2792965006));
ff(B, C, D, A, 15, fs4, Uns(1236535329));
gg(A, B, C, D, 1, gs1, Uns(4129170786)); /* Round 2 */
gg(D, A, B, C, 6, gs2, Uns(3225465664));
gg(C, D, A, B, 11, gs3, Uns(643717713));
gg(B, C, D, A, 0, gs4, Uns(3921069994));
gg(A, B, C, D, 5, gs1, Uns(3593408605));
gg(D, A, B, C, 10, gs2, Uns(38016083));
gg(C, D, A, B, 15, gs3, Uns(3634488961));
gg(B, C, D, A, 4, gs4, Uns(3889429448));
gg(A, B, C, D, 9, gs1, Uns(568446438));
gg(D, A, B, C, 14, gs2, Uns(3275163606));
gg(C, D, A, B, 3, gs3, Uns(4107603335));
gg(B, C, D, A, 8, gs4, Uns(1163531501));
gg(A, B, C, D, 13, gs1, Uns(2850285829));
gg(D, A, B, C, 2, gs2, Uns(4243563512));
gg(C, D, A, B, 7, gs3, Uns(1735328473));
gg(B, C, D, A, 12, gs4, Uns(2368359562));
hh(A, B, C, D, 5, hs1, Uns(4294588738)); /* Round 3 */
hh(D, A, B, C, 8, hs2, Uns(2272392833));
hh(C, D, A, B, 11, hs3, Uns(1839030562));
hh(B, C, D, A, 14, hs4, Uns(4259657740));
hh(A, B, C, D, 1, hs1, Uns(2763975236));
hh(D, A, B, C, 4, hs2, Uns(1272893353));
hh(C, D, A, B, 7, hs3, Uns(4139469664));
hh(B, C, D, A, 10, hs4, Uns(3200236656));
hh(A, B, C, D, 13, hs1, Uns(681279174));
hh(D, A, B, C, 0, hs2, Uns(3936430074));
hh(C, D, A, B, 3, hs3, Uns(3572445317));
hh(B, C, D, A, 6, hs4, Uns(76029189));
hh(A, B, C, D, 9, hs1, Uns(3654602809));
hh(D, A, B, C, 12, hs2, Uns(3873151461));
hh(C, D, A, B, 15, hs3, Uns(530742520));
hh(B, C, D, A, 2, hs4, Uns(3299628645));
ii(A, B, C, D, 0, is1, Uns(4096336452)); /* Round 4 */
ii(D, A, B, C, 7, is2, Uns(1126891415));
ii(C, D, A, B, 14, is3, Uns(2878612391));
ii(B, C, D, A, 5, is4, Uns(4237533241));
ii(A, B, C, D, 12, is1, Uns(1700485571));
ii(D, A, B, C, 3, is2, Uns(2399980690));
ii(C, D, A, B, 10, is3, Uns(4293915773));
ii(B, C, D, A, 1, is4, Uns(2240044497));
ii(A, B, C, D, 8, is1, Uns(1873313359));
ii(D, A, B, C, 15, is2, Uns(4264355552));
ii(C, D, A, B, 6, is3, Uns(2734768916));
ii(B, C, D, A, 13, is4, Uns(1309151649));
ii(A, B, C, D, 4, is1, Uns(4149444226));
ii(D, A, B, C, 11, is2, Uns(3174756917));
ii(C, D, A, B, 2, is3, Uns(718787259));
ii(B, C, D, A, 9, is4, Uns(3951481745));
MDp->buffer[0] += A;
MDp->buffer[1] += B;
MDp->buffer[2] += C;
MDp->buffer[3] += D;
#ifdef WORDS_BIGENDIAN
MDreverse(X);
#endif
}
/*
* 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 MD5 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.
* ** Returns : 0 if processing succeeds or was already done;
* ** -1 if processing was already done
* ** -2 if count was too large
*/
int
MDupdate(MDptr MDp, const unsigned char *X, unsigned int count)
{
unsigned int 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 0;
/*
* check to see if MD is already done and report error
*/
if (MDp->done) {
return -1;
}
/*
* if (MDp->done) { fprintf(stderr,"\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, (const unsigned int *) X);
} else if (count > 512) /* Check for count too large */
return -2;
/*
* { fprintf(stderr,"\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
*/
int copycount;
byte = count >> 3;
bit = count & 7;
copycount = byte;
if (bit)
copycount++;
/*
* Copy X into XX since we need to modify it
*/
memset(XX, 0, sizeof(XX));
memcpy(XX, X, copycount);
/*
* Add padding '1' bit and low-order zeros in last byte
*/
mask = ((unsigned long) 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 int *) XX);
} else { /* need to do two blocks to finish up */
MDblock(MDp, (unsigned int *) 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 int *) XX);
}
/*
* Set flag saying we're done with MD computation
*/
MDp->done = 1;
}
return 0;
}
/*
* MDchecksum(data, len, MD5): do a checksum on an arbirtrary amount of data
*/
int
MDchecksum(const u_char * data, size_t len, u_char * mac, size_t maclen)
{
MDstruct md;
MDstruct *MD = &md;
int rc = 0;
MDbegin(MD);
while (len >= 64) {
rc = MDupdate(MD, data, 64 * 8);
if (rc)
goto check_end;
data += 64;
len -= 64;
}
rc = MDupdate(MD, data, len * 8);
if (rc)
goto check_end;
/*
* copy the checksum to the outgoing data (all of it that is requested).
*/
MDget(MD, mac, maclen);
check_end:
memset(&md, 0, sizeof(md));
return rc;
}
/*
* MDsign(data, len, MD5): do a checksum on an arbirtrary amount
* of data, and prepended with a secret in the standard fashion
*/
int
MDsign(const u_char * data, size_t len, u_char * mac, size_t maclen,
const u_char * secret, size_t secretlen)
{
#define HASHKEYLEN 64
MDstruct MD;
u_char K1[HASHKEYLEN];
u_char K2[HASHKEYLEN];
u_char extendedAuthKey[HASHKEYLEN];
u_char buf[HASHKEYLEN];
size_t i;
const u_char *cp;
u_char *newdata = NULL;
int rc = 0;
/*
* memset(K1,0,HASHKEYLEN);
* memset(K2,0,HASHKEYLEN);
* memset(buf,0,HASHKEYLEN);
* memset(extendedAuthKey,0,HASHKEYLEN);
*/
if (secretlen != 16 || secret == NULL || mac == NULL || data == NULL ||
len <= 0 || maclen <= 0) {
/*
* DEBUGMSGTL(("md5","MD5 signing not properly initialized"));
*/
return -1;
}
memset(extendedAuthKey, 0, HASHKEYLEN);
memcpy(extendedAuthKey, secret, secretlen);
for (i = 0; i < HASHKEYLEN; i++) {
K1[i] = extendedAuthKey[i] ^ 0x36;
K2[i] = extendedAuthKey[i] ^ 0x5c;
}
MDbegin(&MD);
rc = MDupdate(&MD, K1, HASHKEYLEN * 8);
if (rc)
goto update_end;
i = len;
if (((uintptr_t) data) % sizeof(long) != 0) {
/*
* this relies on the ability to use integer math and thus we
* must rely on data that aligns on 32-bit-word-boundries
*/
newdata = netsnmp_memdup(data, len);
cp = newdata;
} else {
cp = data;
}
while (i >= 64) {
rc = MDupdate(&MD, cp, 64 * 8);
if (rc)
goto update_end;
cp += 64;
i -= 64;
}
rc = MDupdate(&MD, cp, i * 8);
if (rc)
goto update_end;
memset(buf, 0, HASHKEYLEN);
MDget(&MD, buf, HASHKEYLEN);
MDbegin(&MD);
rc = MDupdate(&MD, K2, HASHKEYLEN * 8);
if (rc)
goto update_end;
rc = MDupdate(&MD, buf, 16 * 8);
if (rc)
goto update_end;
/*
* copy the sign checksum to the outgoing pointer
*/
MDget(&MD, mac, maclen);
update_end:
memset(buf, 0, HASHKEYLEN);
memset(K1, 0, HASHKEYLEN);
memset(K2, 0, HASHKEYLEN);
memset(extendedAuthKey, 0, HASHKEYLEN);
memset(&MD, 0, sizeof(MD));
if (newdata)
free(newdata);
return rc;
}
void
MDget(MDstruct * MD, u_char * buf, size_t buflen)
{
int i, j;
/*
* copy the checksum to the outgoing data (all of it that is requested).
*/
for (i = 0; i < 4 && i * 4 < (int) buflen; i++)
for (j = 0; j < 4 && i * 4 + j < (int) buflen; j++)
buf[i * 4 + j] = (MD->buffer[i] >> j * 8) & 0xff;
}
/*
* ** End of md5.c
* ****************************(cut)****************************************
*/
#endif /* NETSNMP_DISABLE_MD5 */