md5.c File Reference

#include "md5.h"
#include <stdio.h>
#include <string.h>

Include dependency graph for md5.c:

Go to the source code of this file.

Data Structures
struct	MD5Context

Macros
#define	F1(x, y, z)   (z ^ (x & (y ^ z)))
#define	F2(x, y, z)   F1(z, x, y)
#define	F3(x, y, z)   (x ^ y ^ z)
#define	F4(x, y, z)   (y ^ (x | ~z))
#define	MD5STEP(f, w, x, y, z, data, s)   ( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += x )

Typedefs
typedef unsigned int	uint32
typedef struct MD5Context	MD5_CTX

Functions
void	MD5Init (struct MD5Context *)
void	MD5Update (struct MD5Context *, unsigned const char *, unsigned)
void	MD5Final (unsigned char digest[16], struct MD5Context *)
void	MD5Transform (uint32 buf[4], uint32 const in[16])
static void	byteReverse (unsigned char *buf, unsigned longs)
static void	putu32 (uint32 data, unsigned char *addr)
void	CalculateMD5 (unsigned char *buffer, int length, char *checksum)

Macro Definition Documentation

F1

#define F1	(		x,
			y,
			z
	)		(z ^ (x & (y ^ z)))

Definition at line 178 of file md5.c.

Referenced by MD5Transform().

F2

#define F2	(		x,
			y,
			z
	)		F1(z, x, y)

Definition at line 179 of file md5.c.

Referenced by MD5Transform().

F3

#define F3	(		x,
			y,
			z
	)		(x ^ y ^ z)

Definition at line 180 of file md5.c.

Referenced by MD5Transform().

F4

#define F4	(		x,
			y,
			z
	)		(y ^ (x | ~z))

Definition at line 181 of file md5.c.

Referenced by MD5Transform().

MD5STEP

#define MD5STEP	(		f,
			w,
			x,
			y,
			z,
			data,
			s
	)		( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += x )

Definition at line 184 of file md5.c.

Referenced by MD5Transform().

Typedef Documentation

MD5_CTX

typedef struct MD5Context MD5_CTX

Definition at line 41 of file md5.c.

uint32

typedef unsigned int uint32

Definition at line 24 of file md5.c.

Function Documentation

byteReverse()

static void byteReverse ( unsigned char *  buf, unsigned  longs  )

static

Definition at line 48 of file md5.c.

Referenced by MD5Final(), and MD5Update().

{
        uint32 t;
        do {
                t = (uint32) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
                    ((unsigned) buf[1] << 8 | buf[0]);
                *(uint32 *) buf = t;
                buf += 4;
        } while (--longs);
}

CalculateMD5()

void CalculateMD5	(	unsigned char *	buffer,
		int	length,
		char *	checksum
	)

Wrapper for glib checksum functionality.

Definition at line 275 of file md5.c.

References MD5Final(), MD5Init(), and MD5Update().

{
        int             i;
        struct MD5Context       m_md5;
    unsigned char signature[16];

        MD5Init(&m_md5);
        MD5Update(&m_md5, buffer, length);
        MD5Final(signature, &m_md5);

        for (i = 0; i < 16; i++) {
        sprintf(checksum + i * 2, "%02X", signature[i]);
    }
}

MD5Final()

void MD5Final	(	unsigned char	digest[16],
		struct MD5Context *	ctx
	)

Definition at line 134 of file md5.c.

References MD5Context::bits, MD5Context::buf, byteReverse(), MD5Context::in, MD5Transform(), and putu32().

Referenced by CalculateMD5().

{
        unsigned count;
        unsigned char *p;

        /* Compute number of bytes mod 64 */
        count = (ctx->bits[0] >> 3) & 0x3F;

        /* Set the first char of padding to 0x80.  This is safe since there is
           always at least one byte free */
        p = ctx->in + count;
        *p++ = 0x80;

        /* Bytes of padding needed to make 64 bytes */
        count = 64 - 1 - count;

        /* Pad out to 56 mod 64 */
        if (count < 8) {
                /* Two lots of padding:  Pad the first block to 64 bytes */
                memset(p, 0, count);
                byteReverse(ctx->in, 16);
                MD5Transform(ctx->buf, (uint32 *) ctx->in);

                /* Now fill the next block with 56 bytes */
                memset(ctx->in, 0, 56);
        } else {
                /* Pad block to 56 bytes */
                memset(p, 0, count - 8);
        }
        byteReverse(ctx->in, 14);

        /* Append length in bits and transform */
        putu32(ctx->bits[0], ctx->in + (14 * 4));
        putu32(ctx->bits[1], ctx->in + (15 * 4));

        MD5Transform(ctx->buf, (uint32 *) ctx->in);
        byteReverse((unsigned char *) ctx->buf, 4);
        memcpy(digest, ctx->buf, 16);
        memset(ctx, 0, sizeof(*ctx));   /* In case it's sensitive */
}

MD5Init()

void MD5Init

(

struct MD5Context *

ctx

)

Definition at line 71 of file md5.c.

References MD5Context::bits, and MD5Context::buf.

Referenced by CalculateMD5().

{
        ctx->buf[0] = 0x67452301U;
        ctx->buf[1] = 0xefcdab89U;
        ctx->buf[2] = 0x98badcfeU;
        ctx->buf[3] = 0x10325476U;

        ctx->bits[0] = 0;
        ctx->bits[1] = 0;
}

MD5Transform()

void MD5Transform	(	uint32	buf[4],
		uint32 const	in[16]
	)

Definition at line 192 of file md5.c.

References F1, F2, F3, F4, and MD5STEP.

Referenced by MD5Final(), and MD5Update().

{
        register uint32 a, b, c, d;

        a = buf[0];
        b = buf[1];
        c = buf[2];
        d = buf[3];

        MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478U, 7);
        MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756U, 12);
        MD5STEP(F1, c, d, a, b, in[2] + 0x242070dbU, 17);
        MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceeeU, 22);
        MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0fafU, 7);
        MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62aU, 12);
        MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613U, 17);
        MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501U, 22);
        MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8U, 7);
        MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7afU, 12);
        MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1U, 17);
        MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7beU, 22);
        MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122U, 7);
        MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193U, 12);
        MD5STEP(F1, c, d, a, b, in[14] + 0xa679438eU, 17);
        MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821U, 22);

        MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562U, 5);
        MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340U, 9);
        MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51U, 14);
        MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aaU, 20);
        MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105dU, 5);
        MD5STEP(F2, d, a, b, c, in[10] + 0x02441453U, 9);
        MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681U, 14);
        MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8U, 20);
        MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6U, 5);
        MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6U, 9);
        MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87U, 14);
        MD5STEP(F2, b, c, d, a, in[8] + 0x455a14edU, 20);
        MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905U, 5);
        MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8U, 9);
        MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9U, 14);
        MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8aU, 20);

        MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942U, 4);
        MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681U, 11);
        MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122U, 16);
        MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380cU, 23);
        MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44U, 4);
        MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9U, 11);
        MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60U, 16);
        MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70U, 23);
        MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6U, 4);
        MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127faU, 11);
        MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085U, 16);
        MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05U, 23);
        MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039U, 4);
        MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5U, 11);
        MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8U, 16);
        MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665U, 23);

        MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244U, 6);
        MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97U, 10);
        MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7U, 15);
        MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039U, 21);
        MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3U, 6);
        MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92U, 10);
        MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47dU, 15);
        MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1U, 21);
        MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4fU, 6);
        MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0U, 10);
        MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314U, 15);
        MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1U, 21);
        MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82U, 6);
        MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235U, 10);
        MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bbU, 15);
        MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391U, 21);

        buf[0] += a;
        buf[1] += b;
        buf[2] += c;
        buf[3] += d;
}

MD5Update()

void MD5Update	(	struct MD5Context *	ctx,
		unsigned const char *	buf,
		unsigned	len
	)

Definition at line 86 of file md5.c.

References MD5Context::bits, MD5Context::buf, byteReverse(), MD5Context::in, and MD5Transform().

Referenced by CalculateMD5().

{
        uint32 t;

        /* Update bitcount */

        t = ctx->bits[0];
        if ((ctx->bits[0] = t + ((uint32) len << 3)) < t)
                ctx->bits[1]++; /* Carry from low to high */
        ctx->bits[1] += len >> 29;

        t = (t >> 3) & 0x3f;    /* Bytes already in shsInfo->data */

        /* Handle any leading odd-sized chunks */

        if (t) {
                unsigned char *p = (unsigned char *) ctx->in + t;

                t = 64 - t;
                if (len < t) {
                        memcpy(p, buf, len);
                        return;
                }
                memcpy(p, buf, t);
                byteReverse(ctx->in, 16);
                MD5Transform(ctx->buf, (uint32 *) ctx->in);
                buf += t;
                len -= t;
        }
        /* Process data in 64-byte chunks */

        while (len >= 64) {
                memcpy(ctx->in, buf, 64);
                byteReverse(ctx->in, 16);
                MD5Transform(ctx->buf, (uint32 *) ctx->in);
                buf += 64;
                len -= 64;
        }

        /* Handle any remaining bytes of data. */

        memcpy(ctx->in, buf, len);
}

putu32()

static void putu32 ( uint32  data, unsigned char *  addr  )

static

Definition at line 59 of file md5.c.

Referenced by MD5Final().

{
        addr[0] = (unsigned char)data;
        addr[1] = (unsigned char)(data >> 8);
        addr[2] = (unsigned char)(data >> 16);
        addr[3] = (unsigned char)(data >> 24);
}