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Wed Oct 28 13:31:19 2009 UTC (14 years, 7 months ago) by niro
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tagged 'mkinitrd-6_1_11'
1 niro 816 /*
2     * MD5C.C - RSA Data Security, Inc., MD5 message-digest algorithm
3     *
4     * Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
5     * rights reserved.
6     *
7     * License to copy and use this software is granted provided that it
8     * is identified as the "RSA Data Security, Inc. MD5 Message-Digest
9     * Algorithm" in all material mentioning or referencing this software
10     * or this function.
11     *
12     * License is also granted to make and use derivative works provided
13     * that such works are identified as "derived from the RSA Data
14     * Security, Inc. MD5 Message-Digest Algorithm" in all material
15     * mentioning or referencing the derived work.
16     *
17     * RSA Data Security, Inc. makes no representations concerning either
18     * the merchantability of this software or the suitability of this
19     * software for any particular purpose. It is provided "as is"
20     * without express or implied warranty of any kind.
21     *
22     * These notices must be retained in any copies of any part of this
23     * documentation and/or software.
24     *
25     * $FreeBSD: src/lib/libmd/md5c.c,v 1.9.2.1 1999/08/29 14:57:12 peter Exp $
26     *
27     * This code is the same as the code published by RSA Inc. It has been
28     * edited for clarity and style only.
29     *
30     * ----------------------------------------------------------------------------
31     * The md5_crypt() function was taken from freeBSD's libcrypt and contains
32     * this license:
33     * "THE BEER-WARE LICENSE" (Revision 42):
34     * <phk@login.dknet.dk> wrote this file. As long as you retain this notice you
35     * can do whatever you want with this stuff. If we meet some day, and you think
36     * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
37     *
38     * $FreeBSD: src/lib/libcrypt/crypt.c,v 1.7.2.1 1999/08/29 14:56:33 peter Exp $
39     *
40     * ----------------------------------------------------------------------------
41     * On April 19th, 2001 md5_crypt() was modified to make it reentrant
42     * by Erik Andersen <andersen@uclibc.org>
43     *
44     *
45     * June 28, 2001 Manuel Novoa III
46     *
47     * "Un-inlined" code using loops and static const tables in order to
48     * reduce generated code size (on i386 from approx 4k to approx 2.5k).
49     *
50     * June 29, 2001 Manuel Novoa III
51     *
52     * Completely removed static PADDING array.
53     *
54     * Reintroduced the loop unrolling in MD5_Transform and added the
55     * MD5_SIZE_OVER_SPEED option for configurability. Define below as:
56     * 0 fully unrolled loops
57     * 1 partially unrolled (4 ops per loop)
58     * 2 no unrolling -- introduces the need to swap 4 variables (slow)
59     * 3 no unrolling and all 4 loops merged into one with switch
60     * in each loop (glacial)
61     * On i386, sizes are roughly (-Os -fno-builtin):
62     * 0: 3k 1: 2.5k 2: 2.2k 3: 2k
63     *
64     *
65     * Since SuSv3 does not require crypt_r, modified again August 7, 2002
66     * by Erik Andersen to remove reentrance stuff...
67     */
68    
69     /*
70     * Valid values are 1 (fastest/largest) to 3 (smallest/slowest).
71     */
72     #define MD5_SIZE_OVER_SPEED 3
73    
74     /**********************************************************************/
75    
76     /* MD5 context. */
77     struct MD5Context {
78     uint32_t state[4]; /* state (ABCD) */
79     uint32_t count[2]; /* number of bits, modulo 2^64 (lsb first) */
80     unsigned char buffer[64]; /* input buffer */
81     };
82    
83     static void __md5_Init(struct MD5Context *);
84     static void __md5_Update(struct MD5Context *, const unsigned char *, unsigned int);
85     static void __md5_Pad(struct MD5Context *);
86     static void __md5_Final(unsigned char [16], struct MD5Context *);
87     static void __md5_Transform(uint32_t [4], const unsigned char [64]);
88    
89    
90     #define MD5_MAGIC_STR "$1$"
91     #define MD5_MAGIC_LEN (sizeof(MD5_MAGIC_STR) - 1)
92     static const unsigned char __md5__magic[] = MD5_MAGIC_STR;
93    
94    
95     #ifdef i386
96     #define __md5_Encode memcpy
97     #define __md5_Decode memcpy
98     #else /* i386 */
99    
100     /*
101     * __md5_Encodes input (uint32_t) into output (unsigned char). Assumes len is
102     * a multiple of 4.
103     */
104     static void
105     __md5_Encode(unsigned char *output, uint32_t *input, unsigned int len)
106     {
107     unsigned int i, j;
108    
109     for (i = 0, j = 0; j < len; i++, j += 4) {
110     output[j] = input[i];
111     output[j+1] = (input[i] >> 8);
112     output[j+2] = (input[i] >> 16);
113     output[j+3] = (input[i] >> 24);
114     }
115     }
116    
117     /*
118     * __md5_Decodes input (unsigned char) into output (uint32_t). Assumes len is
119     * a multiple of 4.
120     */
121     static void
122     __md5_Decode(uint32_t *output, const unsigned char *input, unsigned int len)
123     {
124     unsigned int i, j;
125    
126     for (i = 0, j = 0; j < len; i++, j += 4)
127     output[i] = ((uint32_t)input[j]) | (((uint32_t)input[j+1]) << 8) |
128     (((uint32_t)input[j+2]) << 16) | (((uint32_t)input[j+3]) << 24);
129     }
130     #endif /* i386 */
131    
132     /* F, G, H and I are basic MD5 functions. */
133     #define F(x, y, z) (((x) & (y)) | (~(x) & (z)))
134     #define G(x, y, z) (((x) & (z)) | ((y) & ~(z)))
135     #define H(x, y, z) ((x) ^ (y) ^ (z))
136     #define I(x, y, z) ((y) ^ ((x) | ~(z)))
137    
138     /* ROTATE_LEFT rotates x left n bits. */
139     #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
140    
141     /*
142     * FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
143     * Rotation is separate from addition to prevent recomputation.
144     */
145     #define FF(a, b, c, d, x, s, ac) { \
146     (a) += F ((b), (c), (d)) + (x) + (uint32_t)(ac); \
147     (a) = ROTATE_LEFT((a), (s)); \
148     (a) += (b); \
149     }
150     #define GG(a, b, c, d, x, s, ac) { \
151     (a) += G ((b), (c), (d)) + (x) + (uint32_t)(ac); \
152     (a) = ROTATE_LEFT((a), (s)); \
153     (a) += (b); \
154     }
155     #define HH(a, b, c, d, x, s, ac) { \
156     (a) += H ((b), (c), (d)) + (x) + (uint32_t)(ac); \
157     (a) = ROTATE_LEFT((a), (s)); \
158     (a) += (b); \
159     }
160     #define II(a, b, c, d, x, s, ac) { \
161     (a) += I ((b), (c), (d)) + (x) + (uint32_t)(ac); \
162     (a) = ROTATE_LEFT((a), (s)); \
163     (a) += (b); \
164     }
165    
166     /* MD5 initialization. Begins an MD5 operation, writing a new context. */
167     static void __md5_Init(struct MD5Context *context)
168     {
169     context->count[0] = context->count[1] = 0;
170    
171     /* Load magic initialization constants. */
172     context->state[0] = 0x67452301;
173     context->state[1] = 0xefcdab89;
174     context->state[2] = 0x98badcfe;
175     context->state[3] = 0x10325476;
176     }
177    
178     /*
179     * MD5 block update operation. Continues an MD5 message-digest
180     * operation, processing another message block, and updating the
181     * context.
182     */
183     static void __md5_Update(struct MD5Context *context, const unsigned char *input, unsigned int inputLen)
184     {
185     unsigned int i, idx, partLen;
186    
187     /* Compute number of bytes mod 64 */
188     idx = (context->count[0] >> 3) & 0x3F;
189    
190     /* Update number of bits */
191     context->count[0] += (inputLen << 3);
192     if (context->count[0] < (inputLen << 3))
193     context->count[1]++;
194     context->count[1] += (inputLen >> 29);
195    
196     partLen = 64 - idx;
197    
198     /* Transform as many times as possible. */
199     if (inputLen >= partLen) {
200     memcpy(&context->buffer[idx], input, partLen);
201     __md5_Transform(context->state, context->buffer);
202    
203     for (i = partLen; i + 63 < inputLen; i += 64)
204     __md5_Transform(context->state, &input[i]);
205    
206     idx = 0;
207     } else
208     i = 0;
209    
210     /* Buffer remaining input */
211     memcpy(&context->buffer[idx], &input[i], inputLen - i);
212     }
213    
214     /*
215     * MD5 padding. Adds padding followed by original length.
216     */
217     static void __md5_Pad(struct MD5Context *context)
218     {
219     unsigned char bits[8];
220     unsigned int idx, padLen;
221     unsigned char PADDING[64];
222    
223     memset(PADDING, 0, sizeof(PADDING));
224     PADDING[0] = 0x80;
225    
226     /* Save number of bits */
227     __md5_Encode(bits, context->count, 8);
228    
229     /* Pad out to 56 mod 64. */
230     idx = (context->count[0] >> 3) & 0x3f;
231     padLen = (idx < 56) ? (56 - idx) : (120 - idx);
232     __md5_Update(context, PADDING, padLen);
233    
234     /* Append length (before padding) */
235     __md5_Update(context, bits, 8);
236     }
237    
238     /*
239     * MD5 finalization. Ends an MD5 message-digest operation, writing the
240     * the message digest and zeroizing the context.
241     */
242     static void __md5_Final(unsigned char digest[16], struct MD5Context *context)
243     {
244     /* Do padding. */
245     __md5_Pad(context);
246    
247     /* Store state in digest */
248     __md5_Encode(digest, context->state, 16);
249    
250     /* Zeroize sensitive information. */
251     memset(context, 0, sizeof(*context));
252     }
253    
254     /* MD5 basic transformation. Transforms state based on block. */
255     static void __md5_Transform(uint32_t state[4], const unsigned char block[64])
256     {
257     uint32_t a, b, c, d, x[16];
258     #if MD5_SIZE_OVER_SPEED > 1
259     uint32_t temp;
260     const unsigned char *ps;
261    
262     static const unsigned char S[] = {
263     7, 12, 17, 22,
264     5, 9, 14, 20,
265     4, 11, 16, 23,
266     6, 10, 15, 21
267     };
268     #endif /* MD5_SIZE_OVER_SPEED > 1 */
269    
270     #if MD5_SIZE_OVER_SPEED > 0
271     const uint32_t *pc;
272     const unsigned char *pp;
273     int i;
274    
275     static const uint32_t C[] = {
276     /* round 1 */
277     0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee,
278     0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
279     0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be,
280     0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,
281     /* round 2 */
282     0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa,
283     0xd62f105d, 0x2441453, 0xd8a1e681, 0xe7d3fbc8,
284     0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed,
285     0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,
286     /* round 3 */
287     0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c,
288     0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
289     0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x4881d05,
290     0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,
291     /* round 4 */
292     0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039,
293     0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
294     0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1,
295     0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391
296     };
297    
298     static const unsigned char P[] = {
299     0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, /* 1 */
300     1, 6, 11, 0, 5, 10, 15, 4, 9, 14, 3, 8, 13, 2, 7, 12, /* 2 */
301     5, 8, 11, 14, 1, 4, 7, 10, 13, 0, 3, 6, 9, 12, 15, 2, /* 3 */
302     0, 7, 14, 5, 12, 3, 10, 1, 8, 15, 6, 13, 4, 11, 2, 9 /* 4 */
303     };
304    
305     #endif /* MD5_SIZE_OVER_SPEED > 0 */
306    
307     __md5_Decode(x, block, 64);
308    
309     a = state[0]; b = state[1]; c = state[2]; d = state[3];
310    
311     #if MD5_SIZE_OVER_SPEED > 2
312     pc = C; pp = P; ps = S - 4;
313    
314     for (i = 0; i < 64; i++) {
315     if ((i & 0x0f) == 0) ps += 4;
316     temp = a;
317     switch (i>>4) {
318     case 0:
319     temp += F(b, c, d);
320     break;
321     case 1:
322     temp += G(b, c, d);
323     break;
324     case 2:
325     temp += H(b, c, d);
326     break;
327     case 3:
328     temp += I(b, c, d);
329     break;
330     }
331     temp += x[*pp++] + *pc++;
332     temp = ROTATE_LEFT(temp, ps[i & 3]);
333     temp += b;
334     a = d; d = c; c = b; b = temp;
335     }
336     #elif MD5_SIZE_OVER_SPEED > 1
337     pc = C; pp = P; ps = S;
338    
339     /* Round 1 */
340     for (i = 0; i < 16; i++) {
341     FF(a, b, c, d, x[*pp], ps[i & 0x3], *pc); pp++; pc++;
342     temp = d; d = c; c = b; b = a; a = temp;
343     }
344    
345     /* Round 2 */
346     ps += 4;
347     for (; i < 32; i++) {
348     GG(a, b, c, d, x[*pp], ps[i & 0x3], *pc); pp++; pc++;
349     temp = d; d = c; c = b; b = a; a = temp;
350     }
351     /* Round 3 */
352     ps += 4;
353     for (; i < 48; i++) {
354     HH(a, b, c, d, x[*pp], ps[i & 0x3], *pc); pp++; pc++;
355     temp = d; d = c; c = b; b = a; a = temp;
356     }
357    
358     /* Round 4 */
359     ps += 4;
360     for (; i < 64; i++) {
361     II(a, b, c, d, x[*pp], ps[i & 0x3], *pc); pp++; pc++;
362     temp = d; d = c; c = b; b = a; a = temp;
363     }
364     #elif MD5_SIZE_OVER_SPEED > 0
365     pc = C; pp = P;
366    
367     /* Round 1 */
368     for (i = 0; i < 4; i++) {
369     FF(a, b, c, d, x[*pp], 7, *pc); pp++; pc++;
370     FF(d, a, b, c, x[*pp], 12, *pc); pp++; pc++;
371     FF(c, d, a, b, x[*pp], 17, *pc); pp++; pc++;
372     FF(b, c, d, a, x[*pp], 22, *pc); pp++; pc++;
373     }
374    
375     /* Round 2 */
376     for (i = 0; i < 4; i++) {
377     GG(a, b, c, d, x[*pp], 5, *pc); pp++; pc++;
378     GG(d, a, b, c, x[*pp], 9, *pc); pp++; pc++;
379     GG(c, d, a, b, x[*pp], 14, *pc); pp++; pc++;
380     GG(b, c, d, a, x[*pp], 20, *pc); pp++; pc++;
381     }
382     /* Round 3 */
383     for (i = 0; i < 4; i++) {
384     HH(a, b, c, d, x[*pp], 4, *pc); pp++; pc++;
385     HH(d, a, b, c, x[*pp], 11, *pc); pp++; pc++;
386     HH(c, d, a, b, x[*pp], 16, *pc); pp++; pc++;
387     HH(b, c, d, a, x[*pp], 23, *pc); pp++; pc++;
388     }
389    
390     /* Round 4 */
391     for (i = 0; i < 4; i++) {
392     II(a, b, c, d, x[*pp], 6, *pc); pp++; pc++;
393     II(d, a, b, c, x[*pp], 10, *pc); pp++; pc++;
394     II(c, d, a, b, x[*pp], 15, *pc); pp++; pc++;
395     II(b, c, d, a, x[*pp], 21, *pc); pp++; pc++;
396     }
397     #else
398     /* Round 1 */
399     #define S11 7
400     #define S12 12
401     #define S13 17
402     #define S14 22
403     FF(a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
404     FF(d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
405     FF(c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
406     FF(b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
407     FF(a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
408     FF(d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
409     FF(c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
410     FF(b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
411     FF(a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
412     FF(d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
413     FF(c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
414     FF(b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
415     FF(a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
416     FF(d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
417     FF(c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
418     FF(b, c, d, a, x[15], S14, 0x49b40821); /* 16 */
419    
420     /* Round 2 */
421     #define S21 5
422     #define S22 9
423     #define S23 14
424     #define S24 20
425     GG(a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
426     GG(d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
427     GG(c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
428     GG(b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
429     GG(a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
430     GG(d, a, b, c, x[10], S22, 0x2441453); /* 22 */
431     GG(c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
432     GG(b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
433     GG(a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
434     GG(d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
435     GG(c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
436     GG(b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
437     GG(a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
438     GG(d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
439     GG(c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
440     GG(b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */
441    
442     /* Round 3 */
443     #define S31 4
444     #define S32 11
445     #define S33 16
446     #define S34 23
447     HH(a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
448     HH(d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
449     HH(c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
450     HH(b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
451     HH(a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
452     HH(d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
453     HH(c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
454     HH(b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
455     HH(a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
456     HH(d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
457     HH(c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
458     HH(b, c, d, a, x[ 6], S34, 0x4881d05); /* 44 */
459     HH(a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
460     HH(d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
461     HH(c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
462     HH(b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */
463    
464     /* Round 4 */
465     #define S41 6
466     #define S42 10
467     #define S43 15
468     #define S44 21
469     II(a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
470     II(d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
471     II(c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
472     II(b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
473     II(a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
474     II(d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
475     II(c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
476     II(b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
477     II(a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
478     II(d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
479     II(c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
480     II(b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
481     II(a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
482     II(d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
483     II(c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
484     II(b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
485     #endif
486    
487     state[0] += a;
488     state[1] += b;
489     state[2] += c;
490     state[3] += d;
491    
492     /* Zeroize sensitive information. */
493     memset(x, 0, sizeof(x));
494     }
495    
496    
497     static char*
498     __md5_to64(char *s, unsigned v, int n)
499     {
500     while (--n >= 0) {
501     *s++ = ascii64[v & 0x3f];
502     v >>= 6;
503     }
504     return s;
505     }
506    
507     /*
508     * UNIX password
509     *
510     * Use MD5 for what it is best at...
511     */
512     #define MD5_OUT_BUFSIZE 36
513     static char *
514     NOINLINE
515     md5_crypt(char passwd[MD5_OUT_BUFSIZE], const unsigned char *pw, const unsigned char *salt)
516     {
517     const unsigned char *sp, *ep;
518     char *p;
519     unsigned char final[17]; /* final[16] exists only to aid in looping */
520     int sl, pl, i, pw_len;
521     struct MD5Context ctx, ctx1;
522    
523     /* Refine the Salt first */
524     sp = salt;
525    
526     // always true for bbox
527     // /* If it starts with the magic string, then skip that */
528     // if (!strncmp(sp, __md5__magic, MD5_MAGIC_LEN))
529     sp += MD5_MAGIC_LEN;
530    
531     /* It stops at the first '$', max 8 chars */
532     for (ep = sp; *ep && *ep != '$' && ep < (sp+8); ep++)
533     continue;
534    
535     /* get the length of the true salt */
536     sl = ep - sp;
537    
538     __md5_Init(&ctx);
539    
540     /* The password first, since that is what is most unknown */
541     pw_len = strlen((char*)pw);
542     __md5_Update(&ctx, pw, pw_len);
543    
544     /* Then our magic string */
545     __md5_Update(&ctx, __md5__magic, MD5_MAGIC_LEN);
546    
547     /* Then the raw salt */
548     __md5_Update(&ctx, sp, sl);
549    
550     /* Then just as many characters of the MD5(pw, salt, pw) */
551     __md5_Init(&ctx1);
552     __md5_Update(&ctx1, pw, pw_len);
553     __md5_Update(&ctx1, sp, sl);
554     __md5_Update(&ctx1, pw, pw_len);
555     __md5_Final(final, &ctx1);
556     for (pl = pw_len; pl > 0; pl -= 16)
557     __md5_Update(&ctx, final, pl > 16 ? 16 : pl);
558    
559     /* Don't leave anything around in vm they could use. */
560     //TODO: the above comment seems to be wrong. final is used later.
561     memset(final, 0, sizeof(final));
562    
563     /* Then something really weird... */
564     for (i = pw_len; i; i >>= 1) {
565     __md5_Update(&ctx, ((i & 1) ? final : (const unsigned char *) pw), 1);
566     }
567    
568     /* Now make the output string */
569     passwd[0] = '$';
570     passwd[1] = '1';
571     passwd[2] = '$';
572     strncpy(passwd + 3, (char*)sp, sl);
573     passwd[sl + 3] = '$';
574    
575     __md5_Final(final, &ctx);
576    
577     /*
578     * and now, just to make sure things don't run too fast
579     * On a 60 Mhz Pentium this takes 34 msec, so you would
580     * need 30 seconds to build a 1000 entry dictionary...
581     */
582     for (i = 0; i < 1000; i++) {
583     __md5_Init(&ctx1);
584     if (i & 1)
585     __md5_Update(&ctx1, pw, pw_len);
586     else
587     __md5_Update(&ctx1, final, 16);
588    
589     if (i % 3)
590     __md5_Update(&ctx1, sp, sl);
591    
592     if (i % 7)
593     __md5_Update(&ctx1, pw, pw_len);
594    
595     if (i & 1)
596     __md5_Update(&ctx1, final, 16);
597     else
598     __md5_Update(&ctx1, pw, pw_len);
599     __md5_Final(final, &ctx1);
600     }
601    
602     p = passwd + sl + 4; /* 12 bytes max (sl is up to 8 bytes) */
603    
604     /* Add 5*4+2 = 22 bytes of hash, + NUL byte. */
605     final[16] = final[5];
606     for (i = 0; i < 5; i++) {
607     unsigned l = (final[i] << 16) | (final[i+6] << 8) | final[i+12];
608     p = __md5_to64(p, l, 4);
609     }
610     p = __md5_to64(p, final[11], 2);
611     *p = '\0';
612    
613     /* Don't leave anything around in vm they could use. */
614     memset(final, 0, sizeof(final));
615    
616     return passwd;
617     }
618    
619     #undef MD5_SIZE_OVER_SPEED
620     #undef MD5_MAGIC_STR
621     #undef MD5_MAGIC_LEN
622     #undef __md5_Encode
623     #undef __md5_Decode
624     #undef F
625     #undef G
626     #undef H
627     #undef I
628     #undef ROTATE_LEFT
629     #undef FF
630     #undef GG
631     #undef HH
632     #undef II
633     #undef S11
634     #undef S12
635     #undef S13
636     #undef S14
637     #undef S21
638     #undef S22
639     #undef S23
640     #undef S24
641     #undef S31
642     #undef S32
643     #undef S33
644     #undef S34
645     #undef S41
646     #undef S42
647     #undef S43
648     #undef S44