xref: /freebsd/crypto/openssl/ssl/ssl_ciph.c (revision 1b6c76a2fe091c74f08427e6c870851025a9cf67)
1 /* ssl/ssl_ciph.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3  * All rights reserved.
4  *
5  * This package is an SSL implementation written
6  * by Eric Young (eay@cryptsoft.com).
7  * The implementation was written so as to conform with Netscapes SSL.
8  *
9  * This library is free for commercial and non-commercial use as long as
10  * the following conditions are aheared to.  The following conditions
11  * apply to all code found in this distribution, be it the RC4, RSA,
12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13  * included with this distribution is covered by the same copyright terms
14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15  *
16  * Copyright remains Eric Young's, and as such any Copyright notices in
17  * the code are not to be removed.
18  * If this package is used in a product, Eric Young should be given attribution
19  * as the author of the parts of the library used.
20  * This can be in the form of a textual message at program startup or
21  * in documentation (online or textual) provided with the package.
22  *
23  * Redistribution and use in source and binary forms, with or without
24  * modification, are permitted provided that the following conditions
25  * are met:
26  * 1. Redistributions of source code must retain the copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 3. All advertising materials mentioning features or use of this software
32  *    must display the following acknowledgement:
33  *    "This product includes cryptographic software written by
34  *     Eric Young (eay@cryptsoft.com)"
35  *    The word 'cryptographic' can be left out if the rouines from the library
36  *    being used are not cryptographic related :-).
37  * 4. If you include any Windows specific code (or a derivative thereof) from
38  *    the apps directory (application code) you must include an acknowledgement:
39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40  *
41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51  * SUCH DAMAGE.
52  *
53  * The licence and distribution terms for any publically available version or
54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
55  * copied and put under another distribution licence
56  * [including the GNU Public Licence.]
57  */
58 
59 #include <stdio.h>
60 #include <openssl/objects.h>
61 #include <openssl/comp.h>
62 #include "ssl_locl.h"
63 
64 #define SSL_ENC_DES_IDX		0
65 #define SSL_ENC_3DES_IDX	1
66 #define SSL_ENC_RC4_IDX		2
67 #define SSL_ENC_RC2_IDX		3
68 #define SSL_ENC_IDEA_IDX	4
69 #define SSL_ENC_eFZA_IDX	5
70 #define SSL_ENC_NULL_IDX	6
71 #define SSL_ENC_NUM_IDX		7
72 
73 static const EVP_CIPHER *ssl_cipher_methods[SSL_ENC_NUM_IDX]={
74 	NULL,NULL,NULL,NULL,NULL,NULL,
75 	};
76 
77 static STACK_OF(SSL_COMP) *ssl_comp_methods=NULL;
78 
79 #define SSL_MD_MD5_IDX	0
80 #define SSL_MD_SHA1_IDX	1
81 #define SSL_MD_NUM_IDX	2
82 static const EVP_MD *ssl_digest_methods[SSL_MD_NUM_IDX]={
83 	NULL,NULL,
84 	};
85 
86 #define CIPHER_ADD	1
87 #define CIPHER_KILL	2
88 #define CIPHER_DEL	3
89 #define CIPHER_ORD	4
90 #define CIPHER_SPECIAL	5
91 
92 typedef struct cipher_order_st
93 	{
94 	SSL_CIPHER *cipher;
95 	int active;
96 	int dead;
97 	struct cipher_order_st *next,*prev;
98 	} CIPHER_ORDER;
99 
100 static const SSL_CIPHER cipher_aliases[]={
101 	/* Don't include eNULL unless specifically enabled */
102 	{0,SSL_TXT_ALL, 0,SSL_ALL & ~SSL_eNULL, SSL_ALL ,0,0,0,SSL_ALL,SSL_ALL}, /* must be first */
103 	{0,SSL_TXT_kRSA,0,SSL_kRSA,  0,0,0,0,SSL_MKEY_MASK,0},
104 	{0,SSL_TXT_kDHr,0,SSL_kDHr,  0,0,0,0,SSL_MKEY_MASK,0},
105 	{0,SSL_TXT_kDHd,0,SSL_kDHd,  0,0,0,0,SSL_MKEY_MASK,0},
106 	{0,SSL_TXT_kEDH,0,SSL_kEDH,  0,0,0,0,SSL_MKEY_MASK,0},
107 	{0,SSL_TXT_kFZA,0,SSL_kFZA,  0,0,0,0,SSL_MKEY_MASK,0},
108 	{0,SSL_TXT_DH,	0,SSL_DH,    0,0,0,0,SSL_MKEY_MASK,0},
109 	{0,SSL_TXT_EDH,	0,SSL_EDH,   0,0,0,0,SSL_MKEY_MASK|SSL_AUTH_MASK,0},
110 
111 	{0,SSL_TXT_aRSA,0,SSL_aRSA,  0,0,0,0,SSL_AUTH_MASK,0},
112 	{0,SSL_TXT_aDSS,0,SSL_aDSS,  0,0,0,0,SSL_AUTH_MASK,0},
113 	{0,SSL_TXT_aFZA,0,SSL_aFZA,  0,0,0,0,SSL_AUTH_MASK,0},
114 	{0,SSL_TXT_aNULL,0,SSL_aNULL,0,0,0,0,SSL_AUTH_MASK,0},
115 	{0,SSL_TXT_aDH, 0,SSL_aDH,   0,0,0,0,SSL_AUTH_MASK,0},
116 	{0,SSL_TXT_DSS,	0,SSL_DSS,   0,0,0,0,SSL_AUTH_MASK,0},
117 
118 	{0,SSL_TXT_DES,	0,SSL_DES,   0,0,0,0,SSL_ENC_MASK,0},
119 	{0,SSL_TXT_3DES,0,SSL_3DES,  0,0,0,0,SSL_ENC_MASK,0},
120 	{0,SSL_TXT_RC4,	0,SSL_RC4,   0,0,0,0,SSL_ENC_MASK,0},
121 	{0,SSL_TXT_RC2,	0,SSL_RC2,   0,0,0,0,SSL_ENC_MASK,0},
122 	{0,SSL_TXT_IDEA,0,SSL_IDEA,  0,0,0,0,SSL_ENC_MASK,0},
123 	{0,SSL_TXT_eNULL,0,SSL_eNULL,0,0,0,0,SSL_ENC_MASK,0},
124 	{0,SSL_TXT_eFZA,0,SSL_eFZA,  0,0,0,0,SSL_ENC_MASK,0},
125 
126 	{0,SSL_TXT_MD5,	0,SSL_MD5,   0,0,0,0,SSL_MAC_MASK,0},
127 	{0,SSL_TXT_SHA1,0,SSL_SHA1,  0,0,0,0,SSL_MAC_MASK,0},
128 	{0,SSL_TXT_SHA,	0,SSL_SHA,   0,0,0,0,SSL_MAC_MASK,0},
129 
130 	{0,SSL_TXT_NULL,0,SSL_NULL,  0,0,0,0,SSL_ENC_MASK,0},
131 	{0,SSL_TXT_RSA,	0,SSL_RSA,   0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK,0},
132 	{0,SSL_TXT_ADH,	0,SSL_ADH,   0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK,0},
133 	{0,SSL_TXT_FZA,	0,SSL_FZA,   0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK|SSL_ENC_MASK,0},
134 
135 	{0,SSL_TXT_SSLV2, 0,SSL_SSLV2, 0,0,0,0,SSL_SSL_MASK,0},
136 	{0,SSL_TXT_SSLV3, 0,SSL_SSLV3, 0,0,0,0,SSL_SSL_MASK,0},
137 	{0,SSL_TXT_TLSV1, 0,SSL_TLSV1, 0,0,0,0,SSL_SSL_MASK,0},
138 
139 	{0,SSL_TXT_EXP   ,0, 0,SSL_EXPORT, 0,0,0,0,SSL_EXP_MASK},
140 	{0,SSL_TXT_EXPORT,0, 0,SSL_EXPORT, 0,0,0,0,SSL_EXP_MASK},
141 	{0,SSL_TXT_EXP40, 0, 0, SSL_EXP40, 0,0,0,0,SSL_STRONG_MASK},
142 	{0,SSL_TXT_EXP56, 0, 0, SSL_EXP56, 0,0,0,0,SSL_STRONG_MASK},
143 	{0,SSL_TXT_LOW,   0, 0,   SSL_LOW, 0,0,0,0,SSL_STRONG_MASK},
144 	{0,SSL_TXT_MEDIUM,0, 0,SSL_MEDIUM, 0,0,0,0,SSL_STRONG_MASK},
145 	{0,SSL_TXT_HIGH,  0, 0,  SSL_HIGH, 0,0,0,0,SSL_STRONG_MASK},
146 	};
147 
148 static int init_ciphers=1;
149 
150 static void load_ciphers(void)
151 	{
152 	init_ciphers=0;
153 	ssl_cipher_methods[SSL_ENC_DES_IDX]=
154 		EVP_get_cipherbyname(SN_des_cbc);
155 	ssl_cipher_methods[SSL_ENC_3DES_IDX]=
156 		EVP_get_cipherbyname(SN_des_ede3_cbc);
157 	ssl_cipher_methods[SSL_ENC_RC4_IDX]=
158 		EVP_get_cipherbyname(SN_rc4);
159 	ssl_cipher_methods[SSL_ENC_RC2_IDX]=
160 		EVP_get_cipherbyname(SN_rc2_cbc);
161 	ssl_cipher_methods[SSL_ENC_IDEA_IDX]=
162 		EVP_get_cipherbyname(SN_idea_cbc);
163 
164 	ssl_digest_methods[SSL_MD_MD5_IDX]=
165 		EVP_get_digestbyname(SN_md5);
166 	ssl_digest_methods[SSL_MD_SHA1_IDX]=
167 		EVP_get_digestbyname(SN_sha1);
168 	}
169 
170 int ssl_cipher_get_evp(SSL_SESSION *s, const EVP_CIPHER **enc,
171 	     const EVP_MD **md, SSL_COMP **comp)
172 	{
173 	int i;
174 	SSL_CIPHER *c;
175 
176 	c=s->cipher;
177 	if (c == NULL) return(0);
178 	if (comp != NULL)
179 		{
180 		SSL_COMP ctmp;
181 
182 		if (s->compress_meth == 0)
183 			*comp=NULL;
184 		else if (ssl_comp_methods == NULL)
185 			{
186 			/* bad */
187 			*comp=NULL;
188 			}
189 		else
190 			{
191 
192 			ctmp.id=s->compress_meth;
193 			i=sk_SSL_COMP_find(ssl_comp_methods,&ctmp);
194 			if (i >= 0)
195 				*comp=sk_SSL_COMP_value(ssl_comp_methods,i);
196 			else
197 				*comp=NULL;
198 			}
199 		}
200 
201 	if ((enc == NULL) || (md == NULL)) return(0);
202 
203 	switch (c->algorithms & SSL_ENC_MASK)
204 		{
205 	case SSL_DES:
206 		i=SSL_ENC_DES_IDX;
207 		break;
208 	case SSL_3DES:
209 		i=SSL_ENC_3DES_IDX;
210 		break;
211 	case SSL_RC4:
212 		i=SSL_ENC_RC4_IDX;
213 		break;
214 	case SSL_RC2:
215 		i=SSL_ENC_RC2_IDX;
216 		break;
217 	case SSL_IDEA:
218 		i=SSL_ENC_IDEA_IDX;
219 		break;
220 	case SSL_eNULL:
221 		i=SSL_ENC_NULL_IDX;
222 		break;
223 	default:
224 		i= -1;
225 		break;
226 		}
227 
228 	if ((i < 0) || (i > SSL_ENC_NUM_IDX))
229 		*enc=NULL;
230 	else
231 		{
232 		if (i == SSL_ENC_NULL_IDX)
233 			*enc=EVP_enc_null();
234 		else
235 			*enc=ssl_cipher_methods[i];
236 		}
237 
238 	switch (c->algorithms & SSL_MAC_MASK)
239 		{
240 	case SSL_MD5:
241 		i=SSL_MD_MD5_IDX;
242 		break;
243 	case SSL_SHA1:
244 		i=SSL_MD_SHA1_IDX;
245 		break;
246 	default:
247 		i= -1;
248 		break;
249 		}
250 	if ((i < 0) || (i > SSL_MD_NUM_IDX))
251 		*md=NULL;
252 	else
253 		*md=ssl_digest_methods[i];
254 
255 	if ((*enc != NULL) && (*md != NULL))
256 		return(1);
257 	else
258 		return(0);
259 	}
260 
261 #define ITEM_SEP(a) \
262 	(((a) == ':') || ((a) == ' ') || ((a) == ';') || ((a) == ','))
263 
264 static void ll_append_tail(CIPHER_ORDER **head, CIPHER_ORDER *curr,
265 	     CIPHER_ORDER **tail)
266 	{
267 	if (curr == *tail) return;
268 	if (curr == *head)
269 		*head=curr->next;
270 	if (curr->prev != NULL)
271 		curr->prev->next=curr->next;
272 	if (curr->next != NULL) /* should always be true */
273 		curr->next->prev=curr->prev;
274 	(*tail)->next=curr;
275 	curr->prev= *tail;
276 	curr->next=NULL;
277 	*tail=curr;
278 	}
279 
280 static unsigned long ssl_cipher_get_disabled(void)
281 	{
282 	unsigned long mask;
283 
284 	mask = SSL_kFZA;
285 #ifdef NO_RSA
286 	mask |= SSL_aRSA|SSL_kRSA;
287 #endif
288 #ifdef NO_DSA
289 	mask |= SSL_aDSS;
290 #endif
291 #ifdef NO_DH
292 	mask |= SSL_kDHr|SSL_kDHd|SSL_kEDH|SSL_aDH;
293 #endif
294 
295 #ifdef SSL_FORBID_ENULL
296 	mask |= SSL_eNULL;
297 #endif
298 
299 	mask |= (ssl_cipher_methods[SSL_ENC_DES_IDX ] == NULL) ? SSL_DES :0;
300 	mask |= (ssl_cipher_methods[SSL_ENC_3DES_IDX] == NULL) ? SSL_3DES:0;
301 	mask |= (ssl_cipher_methods[SSL_ENC_RC4_IDX ] == NULL) ? SSL_RC4 :0;
302 	mask |= (ssl_cipher_methods[SSL_ENC_RC2_IDX ] == NULL) ? SSL_RC2 :0;
303 	mask |= (ssl_cipher_methods[SSL_ENC_IDEA_IDX] == NULL) ? SSL_IDEA:0;
304 	mask |= (ssl_cipher_methods[SSL_ENC_eFZA_IDX] == NULL) ? SSL_eFZA:0;
305 
306 	mask |= (ssl_digest_methods[SSL_MD_MD5_IDX ] == NULL) ? SSL_MD5 :0;
307 	mask |= (ssl_digest_methods[SSL_MD_SHA1_IDX] == NULL) ? SSL_SHA1:0;
308 
309 	return(mask);
310 	}
311 
312 static void ssl_cipher_collect_ciphers(const SSL_METHOD *ssl_method,
313 		int num_of_ciphers, unsigned long mask, CIPHER_ORDER *list,
314 		CIPHER_ORDER **head_p, CIPHER_ORDER **tail_p)
315 	{
316 	int i, list_num;
317 	SSL_CIPHER *c;
318 
319 	/*
320 	 * We have num_of_ciphers descriptions compiled in, depending on the
321 	 * method selected (SSLv2 and/or SSLv3, TLSv1 etc).
322 	 * These will later be sorted in a linked list with at most num
323 	 * entries.
324 	 */
325 
326 	/* Get the initial list of ciphers */
327 	list_num = 0;	/* actual count of ciphers */
328 	for (i = 0; i < num_of_ciphers; i++)
329 		{
330 		c = ssl_method->get_cipher(i);
331 		/* drop those that use any of that is not available */
332 		if ((c != NULL) && c->valid && !(c->algorithms & mask))
333 			{
334 			list[list_num].cipher = c;
335 			list[list_num].next = NULL;
336 			list[list_num].prev = NULL;
337 			list[list_num].active = 0;
338 			list_num++;
339 			/*
340 			if (!sk_push(ca_list,(char *)c)) goto err;
341 			*/
342 			}
343 		}
344 
345 	/*
346 	 * Prepare linked list from list entries
347 	 */
348 	for (i = 1; i < list_num - 1; i++)
349 		{
350 		list[i].prev = &(list[i-1]);
351 		list[i].next = &(list[i+1]);
352 		}
353 	if (list_num > 0)
354 		{
355 		(*head_p) = &(list[0]);
356 		(*head_p)->prev = NULL;
357 		(*head_p)->next = &(list[1]);
358 		(*tail_p) = &(list[list_num - 1]);
359 		(*tail_p)->prev = &(list[list_num - 2]);
360 		(*tail_p)->next = NULL;
361 		}
362 	}
363 
364 static void ssl_cipher_collect_aliases(SSL_CIPHER **ca_list,
365 			int num_of_group_aliases, unsigned long mask,
366 			CIPHER_ORDER *head)
367 	{
368 	CIPHER_ORDER *ciph_curr;
369 	SSL_CIPHER **ca_curr;
370 	int i;
371 
372 	/*
373 	 * First, add the real ciphers as already collected
374 	 */
375 	ciph_curr = head;
376 	ca_curr = ca_list;
377 	while (ciph_curr != NULL)
378 		{
379 		*ca_curr = ciph_curr->cipher;
380 		ca_curr++;
381 		ciph_curr = ciph_curr->next;
382 		}
383 
384 	/*
385 	 * Now we add the available ones from the cipher_aliases[] table.
386 	 * They represent either an algorithm, that must be fully
387 	 * supported (not match any bit in mask) or represent a cipher
388 	 * strength value (will be added in any case because algorithms=0).
389 	 */
390 	for (i = 0; i < num_of_group_aliases; i++)
391 		{
392 		if ((i == 0) ||		/* always fetch "ALL" */
393 		    !(cipher_aliases[i].algorithms & mask))
394 			{
395 			*ca_curr = (SSL_CIPHER *)(cipher_aliases + i);
396 			ca_curr++;
397 			}
398 		}
399 
400 	*ca_curr = NULL;	/* end of list */
401 	}
402 
403 static void ssl_cipher_apply_rule(unsigned long algorithms, unsigned long mask,
404 		unsigned long algo_strength, unsigned long mask_strength,
405 		int rule, int strength_bits, CIPHER_ORDER *list,
406 		CIPHER_ORDER **head_p, CIPHER_ORDER **tail_p)
407 	{
408 	CIPHER_ORDER *head, *tail, *curr, *curr2, *tail2;
409 	SSL_CIPHER *cp;
410 	unsigned long ma, ma_s;
411 
412 #ifdef CIPHER_DEBUG
413 	printf("Applying rule %d with %08lx %08lx %08lx %08lx (%d)\n",
414 		rule, algorithms, mask, algo_strength, mask_strength,
415 		strength_bits);
416 #endif
417 
418 	curr = head = *head_p;
419 	curr2 = head;
420 	tail2 = tail = *tail_p;
421 	for (;;)
422 		{
423 		if ((curr == NULL) || (curr == tail2)) break;
424 		curr = curr2;
425 		curr2 = curr->next;
426 
427 		cp = curr->cipher;
428 
429 		/*
430 		 * Selection criteria is either the number of strength_bits
431 		 * or the algorithm used.
432 		 */
433 		if (strength_bits == -1)
434 			{
435 			ma = mask & cp->algorithms;
436 			ma_s = mask_strength & cp->algo_strength;
437 
438 #ifdef CIPHER_DEBUG
439 			printf("\nName: %s:\nAlgo = %08lx Algo_strength = %08lx\nMask = %08lx Mask_strength %08lx\n", cp->name, cp->algorithms, cp->algo_strength, mask, mask_strength);
440 			printf("ma = %08lx ma_s %08lx, ma&algo=%08lx, ma_s&algos=%08lx\n", ma, ma_s, ma&algorithms, ma_s&algo_strength);
441 #endif
442 			/*
443 			 * Select: if none of the mask bit was met from the
444 			 * cipher or not all of the bits were met, the
445 			 * selection does not apply.
446 			 */
447 			if (((ma == 0) && (ma_s == 0)) ||
448 			    ((ma & algorithms) != ma) ||
449 			    ((ma_s & algo_strength) != ma_s))
450 				continue; /* does not apply */
451 			}
452 		else if (strength_bits != cp->strength_bits)
453 			continue;	/* does not apply */
454 
455 #ifdef CIPHER_DEBUG
456 		printf("Action = %d\n", rule);
457 #endif
458 
459 		/* add the cipher if it has not been added yet. */
460 		if (rule == CIPHER_ADD)
461 			{
462 			if (!curr->active)
463 				{
464 				ll_append_tail(&head, curr, &tail);
465 				curr->active = 1;
466 				}
467 			}
468 		/* Move the added cipher to this location */
469 		else if (rule == CIPHER_ORD)
470 			{
471 			if (curr->active)
472 				{
473 				ll_append_tail(&head, curr, &tail);
474 				}
475 			}
476 		else if	(rule == CIPHER_DEL)
477 			curr->active = 0;
478 		else if (rule == CIPHER_KILL)
479 			{
480 			if (head == curr)
481 				head = curr->next;
482 			else
483 				curr->prev->next = curr->next;
484 			if (tail == curr)
485 				tail = curr->prev;
486 			curr->active = 0;
487 			if (curr->next != NULL)
488 				curr->next->prev = curr->prev;
489 			if (curr->prev != NULL)
490 				curr->prev->next = curr->next;
491 			curr->next = NULL;
492 			curr->prev = NULL;
493 			}
494 		}
495 
496 	*head_p = head;
497 	*tail_p = tail;
498 	}
499 
500 static int ssl_cipher_strength_sort(CIPHER_ORDER *list, CIPHER_ORDER **head_p,
501 				     CIPHER_ORDER **tail_p)
502 	{
503 	int max_strength_bits, i, *number_uses;
504 	CIPHER_ORDER *curr;
505 
506 	/*
507 	 * This routine sorts the ciphers with descending strength. The sorting
508 	 * must keep the pre-sorted sequence, so we apply the normal sorting
509 	 * routine as '+' movement to the end of the list.
510 	 */
511 	max_strength_bits = 0;
512 	curr = *head_p;
513 	while (curr != NULL)
514 		{
515 		if (curr->active &&
516 		    (curr->cipher->strength_bits > max_strength_bits))
517 		    max_strength_bits = curr->cipher->strength_bits;
518 		curr = curr->next;
519 		}
520 
521 	number_uses = OPENSSL_malloc((max_strength_bits + 1) * sizeof(int));
522 	if (!number_uses)
523 	{
524 		SSLerr(SSL_F_SSL_CIPHER_STRENGTH_SORT,ERR_R_MALLOC_FAILURE);
525 		return(0);
526 	}
527 	memset(number_uses, 0, (max_strength_bits + 1) * sizeof(int));
528 
529 	/*
530 	 * Now find the strength_bits values actually used
531 	 */
532 	curr = *head_p;
533 	while (curr != NULL)
534 		{
535 		if (curr->active)
536 			number_uses[curr->cipher->strength_bits]++;
537 		curr = curr->next;
538 		}
539 	/*
540 	 * Go through the list of used strength_bits values in descending
541 	 * order.
542 	 */
543 	for (i = max_strength_bits; i >= 0; i--)
544 		if (number_uses[i] > 0)
545 			ssl_cipher_apply_rule(0, 0, 0, 0, CIPHER_ORD, i,
546 					list, head_p, tail_p);
547 
548 	OPENSSL_free(number_uses);
549 	return(1);
550 	}
551 
552 static int ssl_cipher_process_rulestr(const char *rule_str,
553 		CIPHER_ORDER *list, CIPHER_ORDER **head_p,
554 		CIPHER_ORDER **tail_p, SSL_CIPHER **ca_list)
555 	{
556 	unsigned long algorithms, mask, algo_strength, mask_strength;
557 	const char *l, *start, *buf;
558 	int j, multi, found, rule, retval, ok, buflen;
559 	char ch;
560 
561 	retval = 1;
562 	l = rule_str;
563 	for (;;)
564 		{
565 		ch = *l;
566 
567 		if (ch == '\0')
568 			break;		/* done */
569 		if (ch == '-')
570 			{ rule = CIPHER_DEL; l++; }
571 		else if (ch == '+')
572 			{ rule = CIPHER_ORD; l++; }
573 		else if (ch == '!')
574 			{ rule = CIPHER_KILL; l++; }
575 		else if (ch == '@')
576 			{ rule = CIPHER_SPECIAL; l++; }
577 		else
578 			{ rule = CIPHER_ADD; }
579 
580 		if (ITEM_SEP(ch))
581 			{
582 			l++;
583 			continue;
584 			}
585 
586 		algorithms = mask = algo_strength = mask_strength = 0;
587 
588 		start=l;
589 		for (;;)
590 			{
591 			ch = *l;
592 			buf = l;
593 			buflen = 0;
594 #ifndef CHARSET_EBCDIC
595 			while (	((ch >= 'A') && (ch <= 'Z')) ||
596 				((ch >= '0') && (ch <= '9')) ||
597 				((ch >= 'a') && (ch <= 'z')) ||
598 				 (ch == '-'))
599 #else
600 			while (	isalnum(ch) || (ch == '-'))
601 #endif
602 				 {
603 				 ch = *(++l);
604 				 buflen++;
605 				 }
606 
607 			if (buflen == 0)
608 				{
609 				/*
610 				 * We hit something we cannot deal with,
611 				 * it is no command or separator nor
612 				 * alphanumeric, so we call this an error.
613 				 */
614 				SSLerr(SSL_F_SSL_CIPHER_PROCESS_RULESTR,
615 				       SSL_R_INVALID_COMMAND);
616 				retval = found = 0;
617 				l++;
618 				break;
619 				}
620 
621 			if (rule == CIPHER_SPECIAL)
622 				{
623 				found = 0; /* unused -- avoid compiler warning */
624 				break;	/* special treatment */
625 				}
626 
627 			/* check for multi-part specification */
628 			if (ch == '+')
629 				{
630 				multi=1;
631 				l++;
632 				}
633 			else
634 				multi=0;
635 
636 			/*
637 			 * Now search for the cipher alias in the ca_list. Be careful
638 			 * with the strncmp, because the "buflen" limitation
639 			 * will make the rule "ADH:SOME" and the cipher
640 			 * "ADH-MY-CIPHER" look like a match for buflen=3.
641 			 * So additionally check whether the cipher name found
642 			 * has the correct length. We can save a strlen() call:
643 			 * just checking for the '\0' at the right place is
644 			 * sufficient, we have to strncmp() anyway.
645 			 */
646 			 j = found = 0;
647 			 while (ca_list[j])
648 				{
649 				if ((ca_list[j]->name[buflen] == '\0') &&
650 				    !strncmp(buf, ca_list[j]->name, buflen))
651 					{
652 					found = 1;
653 					break;
654 					}
655 				else
656 					j++;
657 				}
658 			if (!found)
659 				break;	/* ignore this entry */
660 
661 			algorithms |= ca_list[j]->algorithms;
662 			mask |= ca_list[j]->mask;
663 			algo_strength |= ca_list[j]->algo_strength;
664 			mask_strength |= ca_list[j]->mask_strength;
665 
666 			if (!multi) break;
667 			}
668 
669 		/*
670 		 * Ok, we have the rule, now apply it
671 		 */
672 		if (rule == CIPHER_SPECIAL)
673 			{	/* special command */
674 			ok = 0;
675 			if ((buflen == 8) &&
676 				!strncmp(buf, "STRENGTH", 8))
677 				ok = ssl_cipher_strength_sort(list,
678 					head_p, tail_p);
679 			else
680 				SSLerr(SSL_F_SSL_CIPHER_PROCESS_RULESTR,
681 					SSL_R_INVALID_COMMAND);
682 			if (ok == 0)
683 				retval = 0;
684 			/*
685 			 * We do not support any "multi" options
686 			 * together with "@", so throw away the
687 			 * rest of the command, if any left, until
688 			 * end or ':' is found.
689 			 */
690 			while ((*l != '\0') && ITEM_SEP(*l))
691 				l++;
692 			}
693 		else if (found)
694 			{
695 			ssl_cipher_apply_rule(algorithms, mask,
696 				algo_strength, mask_strength, rule, -1,
697 				list, head_p, tail_p);
698 			}
699 		else
700 			{
701 			while ((*l != '\0') && ITEM_SEP(*l))
702 				l++;
703 			}
704 		if (*l == '\0') break; /* done */
705 		}
706 
707 	return(retval);
708 	}
709 
710 STACK_OF(SSL_CIPHER) *ssl_create_cipher_list(const SSL_METHOD *ssl_method,
711 		STACK_OF(SSL_CIPHER) **cipher_list,
712 		STACK_OF(SSL_CIPHER) **cipher_list_by_id,
713 		const char *rule_str)
714 	{
715 	int ok, num_of_ciphers, num_of_alias_max, num_of_group_aliases;
716 	unsigned long disabled_mask;
717 	STACK_OF(SSL_CIPHER) *cipherstack;
718 	const char *rule_p;
719 	CIPHER_ORDER *list = NULL, *head = NULL, *tail = NULL, *curr;
720 	SSL_CIPHER **ca_list = NULL;
721 
722 	/*
723 	 * Return with error if nothing to do.
724 	 */
725 	if (rule_str == NULL) return(NULL);
726 
727 	if (init_ciphers) load_ciphers();
728 
729 	/*
730 	 * To reduce the work to do we only want to process the compiled
731 	 * in algorithms, so we first get the mask of disabled ciphers.
732 	 */
733 	disabled_mask = ssl_cipher_get_disabled();
734 
735 	/*
736 	 * Now we have to collect the available ciphers from the compiled
737 	 * in ciphers. We cannot get more than the number compiled in, so
738 	 * it is used for allocation.
739 	 */
740 	num_of_ciphers = ssl_method->num_ciphers();
741 	list = (CIPHER_ORDER *)OPENSSL_malloc(sizeof(CIPHER_ORDER) * num_of_ciphers);
742 	if (list == NULL)
743 		{
744 		SSLerr(SSL_F_SSL_CREATE_CIPHER_LIST,ERR_R_MALLOC_FAILURE);
745 		return(NULL);	/* Failure */
746 		}
747 
748 	ssl_cipher_collect_ciphers(ssl_method, num_of_ciphers, disabled_mask,
749 				   list, &head, &tail);
750 
751 	/*
752 	 * We also need cipher aliases for selecting based on the rule_str.
753 	 * There might be two types of entries in the rule_str: 1) names
754 	 * of ciphers themselves 2) aliases for groups of ciphers.
755 	 * For 1) we need the available ciphers and for 2) the cipher
756 	 * groups of cipher_aliases added together in one list (otherwise
757 	 * we would be happy with just the cipher_aliases table).
758 	 */
759 	num_of_group_aliases = sizeof(cipher_aliases) / sizeof(SSL_CIPHER);
760 	num_of_alias_max = num_of_ciphers + num_of_group_aliases + 1;
761 	ca_list =
762 		(SSL_CIPHER **)OPENSSL_malloc(sizeof(SSL_CIPHER *) * num_of_alias_max);
763 	if (ca_list == NULL)
764 		{
765 		OPENSSL_free(list);
766 		SSLerr(SSL_F_SSL_CREATE_CIPHER_LIST,ERR_R_MALLOC_FAILURE);
767 		return(NULL);	/* Failure */
768 		}
769 	ssl_cipher_collect_aliases(ca_list, num_of_group_aliases, disabled_mask,
770 				   head);
771 
772 	/*
773 	 * If the rule_string begins with DEFAULT, apply the default rule
774 	 * before using the (possibly available) additional rules.
775 	 */
776 	ok = 1;
777 	rule_p = rule_str;
778 	if (strncmp(rule_str,"DEFAULT",7) == 0)
779 		{
780 		ok = ssl_cipher_process_rulestr(SSL_DEFAULT_CIPHER_LIST,
781 			list, &head, &tail, ca_list);
782 		rule_p += 7;
783 		if (*rule_p == ':')
784 			rule_p++;
785 		}
786 
787 	if (ok && (strlen(rule_p) > 0))
788 		ok = ssl_cipher_process_rulestr(rule_p, list, &head, &tail,
789 						ca_list);
790 
791 	OPENSSL_free(ca_list);	/* Not needed anymore */
792 
793 	if (!ok)
794 		{	/* Rule processing failure */
795 		OPENSSL_free(list);
796 		return(NULL);
797 		}
798 	/*
799 	 * Allocate new "cipherstack" for the result, return with error
800 	 * if we cannot get one.
801 	 */
802 	if ((cipherstack = sk_SSL_CIPHER_new_null()) == NULL)
803 		{
804 		OPENSSL_free(list);
805 		return(NULL);
806 		}
807 
808 	/*
809 	 * The cipher selection for the list is done. The ciphers are added
810 	 * to the resulting precedence to the STACK_OF(SSL_CIPHER).
811 	 */
812 	for (curr = head; curr != NULL; curr = curr->next)
813 		{
814 		if (curr->active)
815 			{
816 			sk_SSL_CIPHER_push(cipherstack, curr->cipher);
817 #ifdef CIPHER_DEBUG
818 			printf("<%s>\n",curr->cipher->name);
819 #endif
820 			}
821 		}
822 	OPENSSL_free(list);	/* Not needed any longer */
823 
824 	/*
825 	 * The following passage is a little bit odd. If pointer variables
826 	 * were supplied to hold STACK_OF(SSL_CIPHER) return information,
827 	 * the old memory pointed to is free()ed. Then, however, the
828 	 * cipher_list entry will be assigned just a copy of the returned
829 	 * cipher stack. For cipher_list_by_id a copy of the cipher stack
830 	 * will be created. See next comment...
831 	 */
832 	if (cipher_list != NULL)
833 		{
834 		if (*cipher_list != NULL)
835 			sk_SSL_CIPHER_free(*cipher_list);
836 		*cipher_list = cipherstack;
837 		}
838 
839 	if (cipher_list_by_id != NULL)
840 		{
841 		if (*cipher_list_by_id != NULL)
842 			sk_SSL_CIPHER_free(*cipher_list_by_id);
843 		*cipher_list_by_id = sk_SSL_CIPHER_dup(cipherstack);
844 		}
845 
846 	/*
847 	 * Now it is getting really strange. If something failed during
848 	 * the previous pointer assignment or if one of the pointers was
849 	 * not requested, the error condition is met. That might be
850 	 * discussable. The strange thing is however that in this case
851 	 * the memory "ret" pointed to is "free()ed" and hence the pointer
852 	 * cipher_list becomes wild. The memory reserved for
853 	 * cipher_list_by_id however is not "free()ed" and stays intact.
854 	 */
855 	if (	(cipher_list_by_id == NULL) ||
856 		(*cipher_list_by_id == NULL) ||
857 		(cipher_list == NULL) ||
858 		(*cipher_list == NULL))
859 		{
860 		sk_SSL_CIPHER_free(cipherstack);
861 		return(NULL);
862 		}
863 
864 	sk_SSL_CIPHER_set_cmp_func(*cipher_list_by_id,ssl_cipher_ptr_id_cmp);
865 
866 	return(cipherstack);
867 	}
868 
869 char *SSL_CIPHER_description(SSL_CIPHER *cipher, char *buf, int len)
870 	{
871 	int is_export,pkl,kl;
872 	char *ver,*exp;
873 	char *kx,*au,*enc,*mac;
874 	unsigned long alg,alg2,alg_s;
875 	static char *format="%-23s %s Kx=%-8s Au=%-4s Enc=%-9s Mac=%-4s%s\n";
876 
877 	alg=cipher->algorithms;
878 	alg_s=cipher->algo_strength;
879 	alg2=cipher->algorithm2;
880 
881 	is_export=SSL_C_IS_EXPORT(cipher);
882 	pkl=SSL_C_EXPORT_PKEYLENGTH(cipher);
883 	kl=SSL_C_EXPORT_KEYLENGTH(cipher);
884 	exp=is_export?" export":"";
885 
886 	if (alg & SSL_SSLV2)
887 		ver="SSLv2";
888 	else if (alg & SSL_SSLV3)
889 		ver="SSLv3";
890 	else
891 		ver="unknown";
892 
893 	switch (alg&SSL_MKEY_MASK)
894 		{
895 	case SSL_kRSA:
896 		kx=is_export?(pkl == 512 ? "RSA(512)" : "RSA(1024)"):"RSA";
897 		break;
898 	case SSL_kDHr:
899 		kx="DH/RSA";
900 		break;
901 	case SSL_kDHd:
902 		kx="DH/DSS";
903 		break;
904 	case SSL_kFZA:
905 		kx="Fortezza";
906 		break;
907 	case SSL_kEDH:
908 		kx=is_export?(pkl == 512 ? "DH(512)" : "DH(1024)"):"DH";
909 		break;
910 	default:
911 		kx="unknown";
912 		}
913 
914 	switch (alg&SSL_AUTH_MASK)
915 		{
916 	case SSL_aRSA:
917 		au="RSA";
918 		break;
919 	case SSL_aDSS:
920 		au="DSS";
921 		break;
922 	case SSL_aDH:
923 		au="DH";
924 		break;
925 	case SSL_aFZA:
926 	case SSL_aNULL:
927 		au="None";
928 		break;
929 	default:
930 		au="unknown";
931 		break;
932 		}
933 
934 	switch (alg&SSL_ENC_MASK)
935 		{
936 	case SSL_DES:
937 		enc=(is_export && kl == 5)?"DES(40)":"DES(56)";
938 		break;
939 	case SSL_3DES:
940 		enc="3DES(168)";
941 		break;
942 	case SSL_RC4:
943 		enc=is_export?(kl == 5 ? "RC4(40)" : "RC4(56)")
944 		  :((alg2&SSL2_CF_8_BYTE_ENC)?"RC4(64)":"RC4(128)");
945 		break;
946 	case SSL_RC2:
947 		enc=is_export?(kl == 5 ? "RC2(40)" : "RC2(56)"):"RC2(128)";
948 		break;
949 	case SSL_IDEA:
950 		enc="IDEA(128)";
951 		break;
952 	case SSL_eFZA:
953 		enc="Fortezza";
954 		break;
955 	case SSL_eNULL:
956 		enc="None";
957 		break;
958 	default:
959 		enc="unknown";
960 		break;
961 		}
962 
963 	switch (alg&SSL_MAC_MASK)
964 		{
965 	case SSL_MD5:
966 		mac="MD5";
967 		break;
968 	case SSL_SHA1:
969 		mac="SHA1";
970 		break;
971 	default:
972 		mac="unknown";
973 		break;
974 		}
975 
976 	if (buf == NULL)
977 		{
978 		len=128;
979 		buf=OPENSSL_malloc(len);
980 		if (buf == NULL) return("OPENSSL_malloc Error");
981 		}
982 	else if (len < 128)
983 		return("Buffer too small");
984 
985 	BIO_snprintf(buf,len,format,cipher->name,ver,kx,au,enc,mac,exp);
986 	return(buf);
987 	}
988 
989 char *SSL_CIPHER_get_version(SSL_CIPHER *c)
990 	{
991 	int i;
992 
993 	if (c == NULL) return("(NONE)");
994 	i=(int)(c->id>>24L);
995 	if (i == 3)
996 		return("TLSv1/SSLv3");
997 	else if (i == 2)
998 		return("SSLv2");
999 	else
1000 		return("unknown");
1001 	}
1002 
1003 /* return the actual cipher being used */
1004 const char *SSL_CIPHER_get_name(SSL_CIPHER *c)
1005 	{
1006 	if (c != NULL)
1007 		return(c->name);
1008 	return("(NONE)");
1009 	}
1010 
1011 /* number of bits for symmetric cipher */
1012 int SSL_CIPHER_get_bits(SSL_CIPHER *c, int *alg_bits)
1013 	{
1014 	int ret=0;
1015 
1016 	if (c != NULL)
1017 		{
1018 		if (alg_bits != NULL) *alg_bits = c->alg_bits;
1019 		ret = c->strength_bits;
1020 		}
1021 	return(ret);
1022 	}
1023 
1024 SSL_COMP *ssl3_comp_find(STACK_OF(SSL_COMP) *sk, int n)
1025 	{
1026 	SSL_COMP *ctmp;
1027 	int i,nn;
1028 
1029 	if ((n == 0) || (sk == NULL)) return(NULL);
1030 	nn=sk_SSL_COMP_num(sk);
1031 	for (i=0; i<nn; i++)
1032 		{
1033 		ctmp=sk_SSL_COMP_value(sk,i);
1034 		if (ctmp->id == n)
1035 			return(ctmp);
1036 		}
1037 	return(NULL);
1038 	}
1039 
1040 static int sk_comp_cmp(const SSL_COMP * const *a,
1041 			const SSL_COMP * const *b)
1042 	{
1043 	return((*a)->id-(*b)->id);
1044 	}
1045 
1046 STACK_OF(SSL_COMP) *SSL_COMP_get_compression_methods(void)
1047 	{
1048 	return(ssl_comp_methods);
1049 	}
1050 
1051 int SSL_COMP_add_compression_method(int id, COMP_METHOD *cm)
1052 	{
1053 	SSL_COMP *comp;
1054 	STACK_OF(SSL_COMP) *sk;
1055 
1056 	comp=(SSL_COMP *)OPENSSL_malloc(sizeof(SSL_COMP));
1057 	comp->id=id;
1058 	comp->method=cm;
1059 	if (ssl_comp_methods == NULL)
1060 		sk=ssl_comp_methods=sk_SSL_COMP_new(sk_comp_cmp);
1061 	else
1062 		sk=ssl_comp_methods;
1063 	if ((sk == NULL) || !sk_SSL_COMP_push(sk,comp))
1064 		{
1065 		SSLerr(SSL_F_SSL_COMP_ADD_COMPRESSION_METHOD,ERR_R_MALLOC_FAILURE);
1066 		return(0);
1067 		}
1068 	else
1069 		return(1);
1070 	}
1071 
1072