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Diffstat (limited to 'util/md5-utils.c')
| -rw-r--r-- | util/md5-utils.c | 355 |
1 files changed, 355 insertions, 0 deletions
diff --git a/util/md5-utils.c b/util/md5-utils.c new file mode 100644 index 0000000..2b95af1 --- /dev/null +++ b/util/md5-utils.c @@ -0,0 +1,355 @@ +/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */ +/* + * This code implements the MD5 message-digest algorithm. + * The algorithm is due to Ron Rivest. This code was + * written by Colin Plumb in 1993, no copyright is claimed. + * This code is in the public domain; do with it what you wish. + * + * Equivalent code is available from RSA Data Security, Inc. + * This code has been tested against that, and is equivalent, + * except that you don't need to include two pages of legalese + * with every copy. + * + * To compute the message digest of a chunk of bytes, declare an + * MD5Context structure, pass it to md5_init, call md5_update as + * needed on buffers full of bytes, and then call md5_Final, which + * will fill a supplied 16-byte array with the digest. + */ + +/* parts of this file are: + * Written March 1993 by Branko Lankester + * Modified June 1993 by Colin Plumb for altered md5.c. + * Modified October 1995 by Erik Troan for RPM + */ + + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include <stdio.h> +#include <string.h> +#include <sys/types.h> +#include "md5-utils.h" + +#define d(x) + +static void md5_transform (guint32 buf[4], const guint32 in[16]); + +static int _ie = 0x44332211; +static union _endian { int i; char b[4]; } *_endian = (union _endian *) &_ie; +#define IS_BIG_ENDIAN() (_endian->b[0] == '\x44') +#define IS_LITTLE_ENDIAN() (_endian->b[0] == '\x11') + + +/* + * Note: this code is harmless on little-endian machines. + */ +static void +_byte_reverse (unsigned char *buf, guint32 longs) +{ + guint32 t; + + do { + t = (guint32) ((guint32) buf[3] << 8 | buf[2]) << 16 | + ((guint32) buf[1] << 8 | buf[0]); + *(guint32 *) buf = t; + buf += 4; + } while (--longs); +} + + +/** + * md5_init: Initialise an md5 context object + * @ctx: md5 context + * + * Initialise an md5 buffer. + * + **/ +void +md5_init (MD5Context *ctx) +{ + ctx->buf[0] = 0x67452301; + ctx->buf[1] = 0xefcdab89; + ctx->buf[2] = 0x98badcfe; + ctx->buf[3] = 0x10325476; + + ctx->bits[0] = 0; + ctx->bits[1] = 0; + + if (IS_BIG_ENDIAN ()) + ctx->doByteReverse = 1; + else + ctx->doByteReverse = 0; +} + + +/** + * md5_update: add a buffer to md5 hash computation + * @ctx: conetxt object used for md5 computaion + * @buf: buffer to add + * @len: buffer length + * + * Update context to reflect the concatenation of another buffer full + * of bytes. Use this to progressively construct an md5 hash. + **/ +void +md5_update (MD5Context *ctx, const unsigned char *buf, guint32 len) +{ + guint32 t; + + /* Update bitcount */ + t = ctx->bits[0]; + if ((ctx->bits[0] = t + ((guint32) 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); + if (ctx->doByteReverse) + _byte_reverse (ctx->in, 16); + md5_transform (ctx->buf, (guint32 *) ctx->in); + buf += t; + len -= t; + } + + /* Process data in 64-byte chunks */ + while (len >= 64) { + memcpy (ctx->in, buf, 64); + if (ctx->doByteReverse) + _byte_reverse (ctx->in, 16); + md5_transform (ctx->buf, (guint32 *) ctx->in); + buf += 64; + len -= 64; + } + + /* Handle any remaining bytes of data. */ + memcpy (ctx->in, buf, len); +} + + +/* + * Final wrapup - pad to 64-byte boundary with the bit pattern + * 1 0* (64-bit count of bits processed, MSB-first) + */ +/** + * md5_final: copy the final md5 hash to a bufer + * @digest: 16 bytes buffer + * @ctx: context containing the calculated md5 + * + * copy the final md5 hash to a bufer + **/ +void +md5_final (MD5Context *ctx, unsigned char digest[16]) +{ + guint32 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); + if (ctx->doByteReverse) + _byte_reverse (ctx->in, 16); + md5_transform (ctx->buf, (guint32 *) 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); + } + + if (ctx->doByteReverse) + _byte_reverse (ctx->in, 14); + + /* Append length in bits and transform */ + ((guint32 *) ctx->in)[14] = ctx->bits[0]; + ((guint32 *) ctx->in)[15] = ctx->bits[1]; + + md5_transform (ctx->buf, (guint32 *) ctx->in); + if (ctx->doByteReverse) + _byte_reverse ((unsigned char *) ctx->buf, 4); + memcpy (digest, ctx->buf, 16); +} + + +/* The four core functions - F1 is optimized somewhat */ + +/* #define F1(x, y, z) (x & y | ~x & z) */ +#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)) + +/* This is the central step in the MD5 algorithm. */ +#define MD5STEP(f, w, x, y, z, data, s) \ + ( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += x ) + +/* + * The core of the MD5 algorithm, this alters an existing MD5 hash to + * reflect the addition of 16 longwords of new data. md5_Update blocks + * the data and converts bytes into longwords for this routine. + */ +static void +md5_transform (guint32 buf[4], const guint32 in[16]) +{ + register guint32 a, b, c, d; + + a = buf[0]; + b = buf[1]; + c = buf[2]; + d = buf[3]; + + MD5STEP (F1, a, b, c, d, in[0] + 0xd76aa478, 7); + MD5STEP (F1, d, a, b, c, in[1] + 0xe8c7b756, 12); + MD5STEP (F1, c, d, a, b, in[2] + 0x242070db, 17); + MD5STEP (F1, b, c, d, a, in[3] + 0xc1bdceee, 22); + MD5STEP (F1, a, b, c, d, in[4] + 0xf57c0faf, 7); + MD5STEP (F1, d, a, b, c, in[5] + 0x4787c62a, 12); + MD5STEP (F1, c, d, a, b, in[6] + 0xa8304613, 17); + MD5STEP (F1, b, c, d, a, in[7] + 0xfd469501, 22); + MD5STEP (F1, a, b, c, d, in[8] + 0x698098d8, 7); + MD5STEP (F1, d, a, b, c, in[9] + 0x8b44f7af, 12); + MD5STEP (F1, c, d, a, b, in[10] + 0xffff5bb1, 17); + MD5STEP (F1, b, c, d, a, in[11] + 0x895cd7be, 22); + MD5STEP (F1, a, b, c, d, in[12] + 0x6b901122, 7); + MD5STEP (F1, d, a, b, c, in[13] + 0xfd987193, 12); + MD5STEP (F1, c, d, a, b, in[14] + 0xa679438e, 17); + MD5STEP (F1, b, c, d, a, in[15] + 0x49b40821, 22); + + MD5STEP (F2, a, b, c, d, in[1] + 0xf61e2562, 5); + MD5STEP (F2, d, a, b, c, in[6] + 0xc040b340, 9); + MD5STEP (F2, c, d, a, b, in[11] + 0x265e5a51, 14); + MD5STEP (F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20); + MD5STEP (F2, a, b, c, d, in[5] + 0xd62f105d, 5); + MD5STEP (F2, d, a, b, c, in[10] + 0x02441453, 9); + MD5STEP (F2, c, d, a, b, in[15] + 0xd8a1e681, 14); + MD5STEP (F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20); + MD5STEP (F2, a, b, c, d, in[9] + 0x21e1cde6, 5); + MD5STEP (F2, d, a, b, c, in[14] + 0xc33707d6, 9); + MD5STEP (F2, c, d, a, b, in[3] + 0xf4d50d87, 14); + MD5STEP (F2, b, c, d, a, in[8] + 0x455a14ed, 20); + MD5STEP (F2, a, b, c, d, in[13] + 0xa9e3e905, 5); + MD5STEP (F2, d, a, b, c, in[2] + 0xfcefa3f8, 9); + MD5STEP (F2, c, d, a, b, in[7] + 0x676f02d9, 14); + MD5STEP (F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20); + + MD5STEP (F3, a, b, c, d, in[5] + 0xfffa3942, 4); + MD5STEP (F3, d, a, b, c, in[8] + 0x8771f681, 11); + MD5STEP (F3, c, d, a, b, in[11] + 0x6d9d6122, 16); + MD5STEP (F3, b, c, d, a, in[14] + 0xfde5380c, 23); + MD5STEP (F3, a, b, c, d, in[1] + 0xa4beea44, 4); + MD5STEP (F3, d, a, b, c, in[4] + 0x4bdecfa9, 11); + MD5STEP (F3, c, d, a, b, in[7] + 0xf6bb4b60, 16); + MD5STEP (F3, b, c, d, a, in[10] + 0xbebfbc70, 23); + MD5STEP (F3, a, b, c, d, in[13] + 0x289b7ec6, 4); + MD5STEP (F3, d, a, b, c, in[0] + 0xeaa127fa, 11); + MD5STEP (F3, c, d, a, b, in[3] + 0xd4ef3085, 16); + MD5STEP (F3, b, c, d, a, in[6] + 0x04881d05, 23); + MD5STEP (F3, a, b, c, d, in[9] + 0xd9d4d039, 4); + MD5STEP (F3, d, a, b, c, in[12] + 0xe6db99e5, 11); + MD5STEP (F3, c, d, a, b, in[15] + 0x1fa27cf8, 16); + MD5STEP (F3, b, c, d, a, in[2] + 0xc4ac5665, 23); + + MD5STEP (F4, a, b, c, d, in[0] + 0xf4292244, 6); + MD5STEP (F4, d, a, b, c, in[7] + 0x432aff97, 10); + MD5STEP (F4, c, d, a, b, in[14] + 0xab9423a7, 15); + MD5STEP (F4, b, c, d, a, in[5] + 0xfc93a039, 21); + MD5STEP (F4, a, b, c, d, in[12] + 0x655b59c3, 6); + MD5STEP (F4, d, a, b, c, in[3] + 0x8f0ccc92, 10); + MD5STEP (F4, c, d, a, b, in[10] + 0xffeff47d, 15); + MD5STEP (F4, b, c, d, a, in[1] + 0x85845dd1, 21); + MD5STEP (F4, a, b, c, d, in[8] + 0x6fa87e4f, 6); + MD5STEP (F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10); + MD5STEP (F4, c, d, a, b, in[6] + 0xa3014314, 15); + MD5STEP (F4, b, c, d, a, in[13] + 0x4e0811a1, 21); + MD5STEP (F4, a, b, c, d, in[4] + 0xf7537e82, 6); + MD5STEP (F4, d, a, b, c, in[11] + 0xbd3af235, 10); + MD5STEP (F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15); + MD5STEP (F4, b, c, d, a, in[9] + 0xeb86d391, 21); + + buf[0] += a; + buf[1] += b; + buf[2] += c; + buf[3] += d; +} + + +/** + * md5_get_digest: get the md5 hash of a buffer + * @buffer: byte buffer + * @buffer_size: buffer size (in bytes) + * @digest: 16 bytes buffer receiving the hash code. + * + * Get the md5 hash of a buffer. The result is put in + * the 16 bytes buffer @digest . + **/ +void +md5_get_digest (const char *buffer, unsigned int buffer_size, unsigned char digest[16]) +{ + MD5Context ctx; + + md5_init (&ctx); + md5_update (&ctx, (unsigned char *) buffer, buffer_size); + md5_final (&ctx, digest); +} + + +/** + * md5_get_digest_from_file: get the md5 hash of a file + * @filename: file name + * @digest: 16 bytes buffer receiving the hash code. + * + * Get the md5 hash of a file. The result is put in + * the 16 bytes buffer @digest . + **/ +void +md5_get_digest_from_file (const char *filename, unsigned char digest[16]) +{ + MD5Context ctx; + unsigned char buf[1024]; + size_t nread; + FILE *fp; + + d(fprintf (stderr, "generating checksum\n")); + + if (!(fp = fopen (filename, "rb"))) + return; + + md5_init (&ctx); + + while ((nread = fread (buf, 1, 1024, fp)) > 0) + md5_update (&ctx, buf, nread); + + if (ferror (fp)) { + fclose (fp); + return; + } + + md5_final (&ctx, digest); + + fclose (fp); + d(fprintf (stderr, "checksum done\n")); +} |