1  /*
2   * MD5 hash implementation and interface functions
3   * Copyright (c) 2003-2005, Jouni Malinen <j@w1.fi>
4   *
5   * This software may be distributed under the terms of the BSD license.
6   * See README for more details.
7   */
8  
9  #include "includes.h"
10  
11  #include "common.h"
12  #include "md5.h"
13  #include "md5_i.h"
14  #include "crypto.h"
15  
16  
17  static void MD5Transform(u32 buf[4], u32 const in[16]);
18  
19  
20  typedef struct MD5Context MD5_CTX;
21  
22  
23  /**
24   * md5_vector - MD5 hash for data vector
25   * @num_elem: Number of elements in the data vector
26   * @addr: Pointers to the data areas
27   * @len: Lengths of the data blocks
28   * @mac: Buffer for the hash
29   * Returns: 0 on success, -1 of failure
30   */
md5_vector(size_t num_elem,const u8 * addr[],const size_t * len,u8 * mac)31  int md5_vector(size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
32  {
33  	MD5_CTX ctx;
34  	size_t i;
35  
36  	if (TEST_FAIL())
37  		return -1;
38  
39  	MD5Init(&ctx);
40  	for (i = 0; i < num_elem; i++)
41  		MD5Update(&ctx, addr[i], len[i]);
42  	MD5Final(mac, &ctx);
43  	return 0;
44  }
45  
46  
47  /* ===== start - public domain MD5 implementation ===== */
48  /*
49   * This code implements the MD5 message-digest algorithm.
50   * The algorithm is due to Ron Rivest.  This code was
51   * written by Colin Plumb in 1993, no copyright is claimed.
52   * This code is in the public domain; do with it what you wish.
53   *
54   * Equivalent code is available from RSA Data Security, Inc.
55   * This code has been tested against that, and is equivalent,
56   * except that you don't need to include two pages of legalese
57   * with every copy.
58   *
59   * To compute the message digest of a chunk of bytes, declare an
60   * MD5Context structure, pass it to MD5Init, call MD5Update as
61   * needed on buffers full of bytes, and then call MD5Final, which
62   * will fill a supplied 16-byte array with the digest.
63   */
64  
65  #ifndef WORDS_BIGENDIAN
66  #define byteReverse(buf, len)	/* Nothing */
67  #else
68  /*
69   * Note: this code is harmless on little-endian machines.
70   */
byteReverse(unsigned char * buf,unsigned longs)71  static void byteReverse(unsigned char *buf, unsigned longs)
72  {
73      u32 t;
74      do {
75  	t = (u32) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
76  	    ((unsigned) buf[1] << 8 | buf[0]);
77  	*(u32 *) buf = t;
78  	buf += 4;
79      } while (--longs);
80  }
81  #endif
82  
83  /*
84   * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
85   * initialization constants.
86   */
MD5Init(struct MD5Context * ctx)87  void MD5Init(struct MD5Context *ctx)
88  {
89      ctx->buf[0] = 0x67452301;
90      ctx->buf[1] = 0xefcdab89;
91      ctx->buf[2] = 0x98badcfe;
92      ctx->buf[3] = 0x10325476;
93  
94      ctx->bits[0] = 0;
95      ctx->bits[1] = 0;
96  }
97  
98  /*
99   * Update context to reflect the concatenation of another buffer full
100   * of bytes.
101   */
MD5Update(struct MD5Context * ctx,unsigned char const * buf,unsigned len)102  void MD5Update(struct MD5Context *ctx, unsigned char const *buf, unsigned len)
103  {
104      u32 t;
105  
106      /* Update bitcount */
107  
108      t = ctx->bits[0];
109      if ((ctx->bits[0] = t + ((u32) len << 3)) < t)
110  	ctx->bits[1]++;		/* Carry from low to high */
111      ctx->bits[1] += len >> 29;
112  
113      t = (t >> 3) & 0x3f;	/* Bytes already in shsInfo->data */
114  
115      /* Handle any leading odd-sized chunks */
116  
117      if (t) {
118  	unsigned char *p = (unsigned char *) ctx->in + t;
119  
120  	t = 64 - t;
121  	if (len < t) {
122  	    os_memcpy(p, buf, len);
123  	    return;
124  	}
125  	os_memcpy(p, buf, t);
126  	byteReverse(ctx->in, 16);
127  	MD5Transform(ctx->buf, (u32 *) ctx->in);
128  	buf += t;
129  	len -= t;
130      }
131      /* Process data in 64-byte chunks */
132  
133      while (len >= 64) {
134  	os_memcpy(ctx->in, buf, 64);
135  	byteReverse(ctx->in, 16);
136  	MD5Transform(ctx->buf, (u32 *) ctx->in);
137  	buf += 64;
138  	len -= 64;
139      }
140  
141      /* Handle any remaining bytes of data. */
142  
143      os_memcpy(ctx->in, buf, len);
144  }
145  
146  /*
147   * Final wrapup - pad to 64-byte boundary with the bit pattern
148   * 1 0* (64-bit count of bits processed, MSB-first)
149   */
MD5Final(unsigned char digest[16],struct MD5Context * ctx)150  void MD5Final(unsigned char digest[16], struct MD5Context *ctx)
151  {
152      unsigned count;
153      unsigned char *p;
154  
155      /* Compute number of bytes mod 64 */
156      count = (ctx->bits[0] >> 3) & 0x3F;
157  
158      /* Set the first char of padding to 0x80.  This is safe since there is
159         always at least one byte free */
160      p = ctx->in + count;
161      *p++ = 0x80;
162  
163      /* Bytes of padding needed to make 64 bytes */
164      count = 64 - 1 - count;
165  
166      /* Pad out to 56 mod 64 */
167      if (count < 8) {
168  	/* Two lots of padding:  Pad the first block to 64 bytes */
169  	os_memset(p, 0, count);
170  	byteReverse(ctx->in, 16);
171  	MD5Transform(ctx->buf, (u32 *) ctx->in);
172  
173  	/* Now fill the next block with 56 bytes */
174  	os_memset(ctx->in, 0, 56);
175      } else {
176  	/* Pad block to 56 bytes */
177  	os_memset(p, 0, count - 8);
178      }
179      byteReverse(ctx->in, 14);
180  
181      /* Append length in bits and transform */
182      ((u32 *) aliasing_hide_typecast(ctx->in, u32))[14] = ctx->bits[0];
183      ((u32 *) aliasing_hide_typecast(ctx->in, u32))[15] = ctx->bits[1];
184  
185      MD5Transform(ctx->buf, (u32 *) ctx->in);
186      byteReverse((unsigned char *) ctx->buf, 4);
187      os_memcpy(digest, ctx->buf, 16);
188      os_memset(ctx, 0, sizeof(*ctx));	/* In case it's sensitive */
189  }
190  
191  /* The four core functions - F1 is optimized somewhat */
192  
193  /* #define F1(x, y, z) (x & y | ~x & z) */
194  #define F1(x, y, z) (z ^ (x & (y ^ z)))
195  #define F2(x, y, z) F1(z, x, y)
196  #define F3(x, y, z) (x ^ y ^ z)
197  #define F4(x, y, z) (y ^ (x | ~z))
198  
199  /* This is the central step in the MD5 algorithm. */
200  #define MD5STEP(f, w, x, y, z, data, s) \
201  	( w += f(x, y, z) + data,  w = w<<s | w>>(32-s),  w += x )
202  
203  /*
204   * The core of the MD5 algorithm, this alters an existing MD5 hash to
205   * reflect the addition of 16 longwords of new data.  MD5Update blocks
206   * the data and converts bytes into longwords for this routine.
207   */
MD5Transform(u32 buf[4],u32 const in[16])208  static void MD5Transform(u32 buf[4], u32 const in[16])
209  {
210      register u32 a, b, c, d;
211  
212      a = buf[0];
213      b = buf[1];
214      c = buf[2];
215      d = buf[3];
216  
217      MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
218      MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
219      MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
220      MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
221      MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
222      MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
223      MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
224      MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
225      MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
226      MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
227      MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
228      MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
229      MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
230      MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
231      MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
232      MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
233  
234      MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
235      MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
236      MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
237      MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
238      MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
239      MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
240      MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
241      MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
242      MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
243      MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
244      MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
245      MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
246      MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
247      MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
248      MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
249      MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
250  
251      MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
252      MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
253      MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
254      MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
255      MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
256      MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
257      MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
258      MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
259      MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
260      MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
261      MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
262      MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
263      MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
264      MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
265      MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
266      MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
267  
268      MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
269      MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
270      MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
271      MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
272      MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
273      MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
274      MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
275      MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
276      MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
277      MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
278      MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
279      MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
280      MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
281      MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
282      MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
283      MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
284  
285      buf[0] += a;
286      buf[1] += b;
287      buf[2] += c;
288      buf[3] += d;
289  }
290  /* ===== end - public domain MD5 implementation ===== */
291