xref: /freebsd/crypto/openssl/ssl/ssl_ciph.c (revision 4b2eaea43fec8e8792be611dea204071a10b655a)
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_AES128_IDX	7
72 #define SSL_ENC_AES256_IDX	8
73 #define SSL_ENC_NUM_IDX		9
74 
75 static const EVP_CIPHER *ssl_cipher_methods[SSL_ENC_NUM_IDX]={
76 	NULL,NULL,NULL,NULL,NULL,NULL,
77 	};
78 
79 static STACK_OF(SSL_COMP) *ssl_comp_methods=NULL;
80 
81 #define SSL_MD_MD5_IDX	0
82 #define SSL_MD_SHA1_IDX	1
83 #define SSL_MD_NUM_IDX	2
84 static const EVP_MD *ssl_digest_methods[SSL_MD_NUM_IDX]={
85 	NULL,NULL,
86 	};
87 
88 #define CIPHER_ADD	1
89 #define CIPHER_KILL	2
90 #define CIPHER_DEL	3
91 #define CIPHER_ORD	4
92 #define CIPHER_SPECIAL	5
93 
94 typedef struct cipher_order_st
95 	{
96 	SSL_CIPHER *cipher;
97 	int active;
98 	int dead;
99 	struct cipher_order_st *next,*prev;
100 	} CIPHER_ORDER;
101 
102 static const SSL_CIPHER cipher_aliases[]={
103 	/* Don't include eNULL unless specifically enabled. */
104 	{0,SSL_TXT_ALL, 0,SSL_ALL & ~SSL_eNULL, SSL_ALL ,0,0,0,SSL_ALL,SSL_ALL}, /* must be first */
105         {0,SSL_TXT_CMPALL,0,SSL_eNULL,0,0,0,0,SSL_ENC_MASK,0},  /* COMPLEMENT OF ALL */
106 	{0,SSL_TXT_CMPDEF,0,SSL_ADH, 0,0,0,0,SSL_AUTH_MASK,0},
107         {0,SSL_TXT_kKRB5,0,SSL_kKRB5,0,0,0,0,SSL_MKEY_MASK,0},  /* VRS Kerberos5 */
108 	{0,SSL_TXT_kRSA,0,SSL_kRSA,  0,0,0,0,SSL_MKEY_MASK,0},
109 	{0,SSL_TXT_kDHr,0,SSL_kDHr,  0,0,0,0,SSL_MKEY_MASK,0},
110 	{0,SSL_TXT_kDHd,0,SSL_kDHd,  0,0,0,0,SSL_MKEY_MASK,0},
111 	{0,SSL_TXT_kEDH,0,SSL_kEDH,  0,0,0,0,SSL_MKEY_MASK,0},
112 	{0,SSL_TXT_kFZA,0,SSL_kFZA,  0,0,0,0,SSL_MKEY_MASK,0},
113 	{0,SSL_TXT_DH,	0,SSL_DH,    0,0,0,0,SSL_MKEY_MASK,0},
114 	{0,SSL_TXT_EDH,	0,SSL_EDH,   0,0,0,0,SSL_MKEY_MASK|SSL_AUTH_MASK,0},
115 
116 	{0,SSL_TXT_aKRB5,0,SSL_aKRB5,0,0,0,0,SSL_AUTH_MASK,0},  /* VRS Kerberos5 */
117 	{0,SSL_TXT_aRSA,0,SSL_aRSA,  0,0,0,0,SSL_AUTH_MASK,0},
118 	{0,SSL_TXT_aDSS,0,SSL_aDSS,  0,0,0,0,SSL_AUTH_MASK,0},
119 	{0,SSL_TXT_aFZA,0,SSL_aFZA,  0,0,0,0,SSL_AUTH_MASK,0},
120 	{0,SSL_TXT_aNULL,0,SSL_aNULL,0,0,0,0,SSL_AUTH_MASK,0},
121 	{0,SSL_TXT_aDH, 0,SSL_aDH,   0,0,0,0,SSL_AUTH_MASK,0},
122 	{0,SSL_TXT_DSS,	0,SSL_DSS,   0,0,0,0,SSL_AUTH_MASK,0},
123 
124 	{0,SSL_TXT_DES,	0,SSL_DES,   0,0,0,0,SSL_ENC_MASK,0},
125 	{0,SSL_TXT_3DES,0,SSL_3DES,  0,0,0,0,SSL_ENC_MASK,0},
126 	{0,SSL_TXT_RC4,	0,SSL_RC4,   0,0,0,0,SSL_ENC_MASK,0},
127 	{0,SSL_TXT_RC2,	0,SSL_RC2,   0,0,0,0,SSL_ENC_MASK,0},
128 	{0,SSL_TXT_IDEA,0,SSL_IDEA,  0,0,0,0,SSL_ENC_MASK,0},
129 	{0,SSL_TXT_eNULL,0,SSL_eNULL,0,0,0,0,SSL_ENC_MASK,0},
130 	{0,SSL_TXT_eFZA,0,SSL_eFZA,  0,0,0,0,SSL_ENC_MASK,0},
131 	{0,SSL_TXT_AES,	0,SSL_AES,   0,0,0,0,SSL_ENC_MASK,0},
132 
133 	{0,SSL_TXT_MD5,	0,SSL_MD5,   0,0,0,0,SSL_MAC_MASK,0},
134 	{0,SSL_TXT_SHA1,0,SSL_SHA1,  0,0,0,0,SSL_MAC_MASK,0},
135 	{0,SSL_TXT_SHA,	0,SSL_SHA,   0,0,0,0,SSL_MAC_MASK,0},
136 
137 	{0,SSL_TXT_NULL,0,SSL_NULL,  0,0,0,0,SSL_ENC_MASK,0},
138 	{0,SSL_TXT_KRB5,0,SSL_KRB5,  0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK,0},
139 	{0,SSL_TXT_RSA,	0,SSL_RSA,   0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK,0},
140 	{0,SSL_TXT_ADH,	0,SSL_ADH,   0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK,0},
141 	{0,SSL_TXT_FZA,	0,SSL_FZA,   0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK|SSL_ENC_MASK,0},
142 
143 	{0,SSL_TXT_SSLV2, 0,SSL_SSLV2, 0,0,0,0,SSL_SSL_MASK,0},
144 	{0,SSL_TXT_SSLV3, 0,SSL_SSLV3, 0,0,0,0,SSL_SSL_MASK,0},
145 	{0,SSL_TXT_TLSV1, 0,SSL_TLSV1, 0,0,0,0,SSL_SSL_MASK,0},
146 
147 	{0,SSL_TXT_EXP   ,0, 0,SSL_EXPORT, 0,0,0,0,SSL_EXP_MASK},
148 	{0,SSL_TXT_EXPORT,0, 0,SSL_EXPORT, 0,0,0,0,SSL_EXP_MASK},
149 	{0,SSL_TXT_EXP40, 0, 0, SSL_EXP40, 0,0,0,0,SSL_STRONG_MASK},
150 	{0,SSL_TXT_EXP56, 0, 0, SSL_EXP56, 0,0,0,0,SSL_STRONG_MASK},
151 	{0,SSL_TXT_LOW,   0, 0,   SSL_LOW, 0,0,0,0,SSL_STRONG_MASK},
152 	{0,SSL_TXT_MEDIUM,0, 0,SSL_MEDIUM, 0,0,0,0,SSL_STRONG_MASK},
153 	{0,SSL_TXT_HIGH,  0, 0,  SSL_HIGH, 0,0,0,0,SSL_STRONG_MASK},
154 	};
155 
156 static int init_ciphers=1;
157 
158 static void load_ciphers(void)
159 	{
160 	init_ciphers=0;
161 	ssl_cipher_methods[SSL_ENC_DES_IDX]=
162 		EVP_get_cipherbyname(SN_des_cbc);
163 	ssl_cipher_methods[SSL_ENC_3DES_IDX]=
164 		EVP_get_cipherbyname(SN_des_ede3_cbc);
165 	ssl_cipher_methods[SSL_ENC_RC4_IDX]=
166 		EVP_get_cipherbyname(SN_rc4);
167 	ssl_cipher_methods[SSL_ENC_RC2_IDX]=
168 		EVP_get_cipherbyname(SN_rc2_cbc);
169 	ssl_cipher_methods[SSL_ENC_IDEA_IDX]=
170 		EVP_get_cipherbyname(SN_idea_cbc);
171 	ssl_cipher_methods[SSL_ENC_AES128_IDX]=
172 	  EVP_get_cipherbyname(SN_aes_128_cbc);
173 	ssl_cipher_methods[SSL_ENC_AES256_IDX]=
174 	  EVP_get_cipherbyname(SN_aes_256_cbc);
175 
176 	ssl_digest_methods[SSL_MD_MD5_IDX]=
177 		EVP_get_digestbyname(SN_md5);
178 	ssl_digest_methods[SSL_MD_SHA1_IDX]=
179 		EVP_get_digestbyname(SN_sha1);
180 	}
181 
182 int ssl_cipher_get_evp(SSL_SESSION *s, const EVP_CIPHER **enc,
183 	     const EVP_MD **md, SSL_COMP **comp)
184 	{
185 	int i;
186 	SSL_CIPHER *c;
187 
188 	c=s->cipher;
189 	if (c == NULL) return(0);
190 	if (comp != NULL)
191 		{
192 		SSL_COMP ctmp;
193 
194 		if (s->compress_meth == 0)
195 			*comp=NULL;
196 		else if (ssl_comp_methods == NULL)
197 			{
198 			/* bad */
199 			*comp=NULL;
200 			}
201 		else
202 			{
203 
204 			ctmp.id=s->compress_meth;
205 			i=sk_SSL_COMP_find(ssl_comp_methods,&ctmp);
206 			if (i >= 0)
207 				*comp=sk_SSL_COMP_value(ssl_comp_methods,i);
208 			else
209 				*comp=NULL;
210 			}
211 		}
212 
213 	if ((enc == NULL) || (md == NULL)) return(0);
214 
215 	switch (c->algorithms & SSL_ENC_MASK)
216 		{
217 	case SSL_DES:
218 		i=SSL_ENC_DES_IDX;
219 		break;
220 	case SSL_3DES:
221 		i=SSL_ENC_3DES_IDX;
222 		break;
223 	case SSL_RC4:
224 		i=SSL_ENC_RC4_IDX;
225 		break;
226 	case SSL_RC2:
227 		i=SSL_ENC_RC2_IDX;
228 		break;
229 	case SSL_IDEA:
230 		i=SSL_ENC_IDEA_IDX;
231 		break;
232 	case SSL_eNULL:
233 		i=SSL_ENC_NULL_IDX;
234 		break;
235 	case SSL_AES:
236 		switch(c->alg_bits)
237 			{
238 		case 128: i=SSL_ENC_AES128_IDX; break;
239 		case 256: i=SSL_ENC_AES256_IDX; break;
240 		default: i=-1; break;
241 			}
242 		break;
243 	default:
244 		i= -1;
245 		break;
246 		}
247 
248 	if ((i < 0) || (i > SSL_ENC_NUM_IDX))
249 		*enc=NULL;
250 	else
251 		{
252 		if (i == SSL_ENC_NULL_IDX)
253 			*enc=EVP_enc_null();
254 		else
255 			*enc=ssl_cipher_methods[i];
256 		}
257 
258 	switch (c->algorithms & SSL_MAC_MASK)
259 		{
260 	case SSL_MD5:
261 		i=SSL_MD_MD5_IDX;
262 		break;
263 	case SSL_SHA1:
264 		i=SSL_MD_SHA1_IDX;
265 		break;
266 	default:
267 		i= -1;
268 		break;
269 		}
270 	if ((i < 0) || (i > SSL_MD_NUM_IDX))
271 		*md=NULL;
272 	else
273 		*md=ssl_digest_methods[i];
274 
275 	if ((*enc != NULL) && (*md != NULL))
276 		return(1);
277 	else
278 		return(0);
279 	}
280 
281 #define ITEM_SEP(a) \
282 	(((a) == ':') || ((a) == ' ') || ((a) == ';') || ((a) == ','))
283 
284 static void ll_append_tail(CIPHER_ORDER **head, CIPHER_ORDER *curr,
285 	     CIPHER_ORDER **tail)
286 	{
287 	if (curr == *tail) return;
288 	if (curr == *head)
289 		*head=curr->next;
290 	if (curr->prev != NULL)
291 		curr->prev->next=curr->next;
292 	if (curr->next != NULL) /* should always be true */
293 		curr->next->prev=curr->prev;
294 	(*tail)->next=curr;
295 	curr->prev= *tail;
296 	curr->next=NULL;
297 	*tail=curr;
298 	}
299 
300 static unsigned long ssl_cipher_get_disabled(void)
301 	{
302 	unsigned long mask;
303 
304 	mask = SSL_kFZA;
305 #ifdef OPENSSL_NO_RSA
306 	mask |= SSL_aRSA|SSL_kRSA;
307 #endif
308 #ifdef OPENSSL_NO_DSA
309 	mask |= SSL_aDSS;
310 #endif
311 #ifdef OPENSSL_NO_DH
312 	mask |= SSL_kDHr|SSL_kDHd|SSL_kEDH|SSL_aDH;
313 #endif
314 #ifdef OPENSSL_NO_KRB5
315 	mask |= SSL_kKRB5|SSL_aKRB5;
316 #endif
317 
318 #ifdef SSL_FORBID_ENULL
319 	mask |= SSL_eNULL;
320 #endif
321 
322 	mask |= (ssl_cipher_methods[SSL_ENC_DES_IDX ] == NULL) ? SSL_DES :0;
323 	mask |= (ssl_cipher_methods[SSL_ENC_3DES_IDX] == NULL) ? SSL_3DES:0;
324 	mask |= (ssl_cipher_methods[SSL_ENC_RC4_IDX ] == NULL) ? SSL_RC4 :0;
325 	mask |= (ssl_cipher_methods[SSL_ENC_RC2_IDX ] == NULL) ? SSL_RC2 :0;
326 	mask |= (ssl_cipher_methods[SSL_ENC_IDEA_IDX] == NULL) ? SSL_IDEA:0;
327 	mask |= (ssl_cipher_methods[SSL_ENC_eFZA_IDX] == NULL) ? SSL_eFZA:0;
328 	mask |= (ssl_cipher_methods[SSL_ENC_AES128_IDX] == NULL) ? SSL_AES:0;
329 
330 	mask |= (ssl_digest_methods[SSL_MD_MD5_IDX ] == NULL) ? SSL_MD5 :0;
331 	mask |= (ssl_digest_methods[SSL_MD_SHA1_IDX] == NULL) ? SSL_SHA1:0;
332 
333 	return(mask);
334 	}
335 
336 static void ssl_cipher_collect_ciphers(const SSL_METHOD *ssl_method,
337 		int num_of_ciphers, unsigned long mask, CIPHER_ORDER *list,
338 		CIPHER_ORDER **head_p, CIPHER_ORDER **tail_p)
339 	{
340 	int i, list_num;
341 	SSL_CIPHER *c;
342 
343 	/*
344 	 * We have num_of_ciphers descriptions compiled in, depending on the
345 	 * method selected (SSLv2 and/or SSLv3, TLSv1 etc).
346 	 * These will later be sorted in a linked list with at most num
347 	 * entries.
348 	 */
349 
350 	/* Get the initial list of ciphers */
351 	list_num = 0;	/* actual count of ciphers */
352 	for (i = 0; i < num_of_ciphers; i++)
353 		{
354 		c = ssl_method->get_cipher(i);
355 		/* drop those that use any of that is not available */
356 		if ((c != NULL) && c->valid && !(c->algorithms & mask))
357 			{
358 			list[list_num].cipher = c;
359 			list[list_num].next = NULL;
360 			list[list_num].prev = NULL;
361 			list[list_num].active = 0;
362 			list_num++;
363 #ifdef KSSL_DEBUG
364 			printf("\t%d: %s %lx %lx\n",i,c->name,c->id,c->algorithms);
365 #endif	/* KSSL_DEBUG */
366 			/*
367 			if (!sk_push(ca_list,(char *)c)) goto err;
368 			*/
369 			}
370 		}
371 
372 	/*
373 	 * Prepare linked list from list entries
374 	 */
375 	for (i = 1; i < list_num - 1; i++)
376 		{
377 		list[i].prev = &(list[i-1]);
378 		list[i].next = &(list[i+1]);
379 		}
380 	if (list_num > 0)
381 		{
382 		(*head_p) = &(list[0]);
383 		(*head_p)->prev = NULL;
384 		(*head_p)->next = &(list[1]);
385 		(*tail_p) = &(list[list_num - 1]);
386 		(*tail_p)->prev = &(list[list_num - 2]);
387 		(*tail_p)->next = NULL;
388 		}
389 	}
390 
391 static void ssl_cipher_collect_aliases(SSL_CIPHER **ca_list,
392 			int num_of_group_aliases, unsigned long mask,
393 			CIPHER_ORDER *head)
394 	{
395 	CIPHER_ORDER *ciph_curr;
396 	SSL_CIPHER **ca_curr;
397 	int i;
398 
399 	/*
400 	 * First, add the real ciphers as already collected
401 	 */
402 	ciph_curr = head;
403 	ca_curr = ca_list;
404 	while (ciph_curr != NULL)
405 		{
406 		*ca_curr = ciph_curr->cipher;
407 		ca_curr++;
408 		ciph_curr = ciph_curr->next;
409 		}
410 
411 	/*
412 	 * Now we add the available ones from the cipher_aliases[] table.
413 	 * They represent either an algorithm, that must be fully
414 	 * supported (not match any bit in mask) or represent a cipher
415 	 * strength value (will be added in any case because algorithms=0).
416 	 */
417 	for (i = 0; i < num_of_group_aliases; i++)
418 		{
419 		if ((i == 0) ||		/* always fetch "ALL" */
420 		    !(cipher_aliases[i].algorithms & mask))
421 			{
422 			*ca_curr = (SSL_CIPHER *)(cipher_aliases + i);
423 			ca_curr++;
424 			}
425 		}
426 
427 	*ca_curr = NULL;	/* end of list */
428 	}
429 
430 static void ssl_cipher_apply_rule(unsigned long algorithms, unsigned long mask,
431 		unsigned long algo_strength, unsigned long mask_strength,
432 		int rule, int strength_bits, CIPHER_ORDER *list,
433 		CIPHER_ORDER **head_p, CIPHER_ORDER **tail_p)
434 	{
435 	CIPHER_ORDER *head, *tail, *curr, *curr2, *tail2;
436 	SSL_CIPHER *cp;
437 	unsigned long ma, ma_s;
438 
439 #ifdef CIPHER_DEBUG
440 	printf("Applying rule %d with %08lx %08lx %08lx %08lx (%d)\n",
441 		rule, algorithms, mask, algo_strength, mask_strength,
442 		strength_bits);
443 #endif
444 
445 	curr = head = *head_p;
446 	curr2 = head;
447 	tail2 = tail = *tail_p;
448 	for (;;)
449 		{
450 		if ((curr == NULL) || (curr == tail2)) break;
451 		curr = curr2;
452 		curr2 = curr->next;
453 
454 		cp = curr->cipher;
455 
456 		/*
457 		 * Selection criteria is either the number of strength_bits
458 		 * or the algorithm used.
459 		 */
460 		if (strength_bits == -1)
461 			{
462 			ma = mask & cp->algorithms;
463 			ma_s = mask_strength & cp->algo_strength;
464 
465 #ifdef CIPHER_DEBUG
466 			printf("\nName: %s:\nAlgo = %08lx Algo_strength = %08lx\nMask = %08lx Mask_strength %08lx\n", cp->name, cp->algorithms, cp->algo_strength, mask, mask_strength);
467 			printf("ma = %08lx ma_s %08lx, ma&algo=%08lx, ma_s&algos=%08lx\n", ma, ma_s, ma&algorithms, ma_s&algo_strength);
468 #endif
469 			/*
470 			 * Select: if none of the mask bit was met from the
471 			 * cipher or not all of the bits were met, the
472 			 * selection does not apply.
473 			 */
474 			if (((ma == 0) && (ma_s == 0)) ||
475 			    ((ma & algorithms) != ma) ||
476 			    ((ma_s & algo_strength) != ma_s))
477 				continue; /* does not apply */
478 			}
479 		else if (strength_bits != cp->strength_bits)
480 			continue;	/* does not apply */
481 
482 #ifdef CIPHER_DEBUG
483 		printf("Action = %d\n", rule);
484 #endif
485 
486 		/* add the cipher if it has not been added yet. */
487 		if (rule == CIPHER_ADD)
488 			{
489 			if (!curr->active)
490 				{
491 				ll_append_tail(&head, curr, &tail);
492 				curr->active = 1;
493 				}
494 			}
495 		/* Move the added cipher to this location */
496 		else if (rule == CIPHER_ORD)
497 			{
498 			if (curr->active)
499 				{
500 				ll_append_tail(&head, curr, &tail);
501 				}
502 			}
503 		else if	(rule == CIPHER_DEL)
504 			curr->active = 0;
505 		else if (rule == CIPHER_KILL)
506 			{
507 			if (head == curr)
508 				head = curr->next;
509 			else
510 				curr->prev->next = curr->next;
511 			if (tail == curr)
512 				tail = curr->prev;
513 			curr->active = 0;
514 			if (curr->next != NULL)
515 				curr->next->prev = curr->prev;
516 			if (curr->prev != NULL)
517 				curr->prev->next = curr->next;
518 			curr->next = NULL;
519 			curr->prev = NULL;
520 			}
521 		}
522 
523 	*head_p = head;
524 	*tail_p = tail;
525 	}
526 
527 static int ssl_cipher_strength_sort(CIPHER_ORDER *list, CIPHER_ORDER **head_p,
528 				     CIPHER_ORDER **tail_p)
529 	{
530 	int max_strength_bits, i, *number_uses;
531 	CIPHER_ORDER *curr;
532 
533 	/*
534 	 * This routine sorts the ciphers with descending strength. The sorting
535 	 * must keep the pre-sorted sequence, so we apply the normal sorting
536 	 * routine as '+' movement to the end of the list.
537 	 */
538 	max_strength_bits = 0;
539 	curr = *head_p;
540 	while (curr != NULL)
541 		{
542 		if (curr->active &&
543 		    (curr->cipher->strength_bits > max_strength_bits))
544 		    max_strength_bits = curr->cipher->strength_bits;
545 		curr = curr->next;
546 		}
547 
548 	number_uses = OPENSSL_malloc((max_strength_bits + 1) * sizeof(int));
549 	if (!number_uses)
550 	{
551 		SSLerr(SSL_F_SSL_CIPHER_STRENGTH_SORT,ERR_R_MALLOC_FAILURE);
552 		return(0);
553 	}
554 	memset(number_uses, 0, (max_strength_bits + 1) * sizeof(int));
555 
556 	/*
557 	 * Now find the strength_bits values actually used
558 	 */
559 	curr = *head_p;
560 	while (curr != NULL)
561 		{
562 		if (curr->active)
563 			number_uses[curr->cipher->strength_bits]++;
564 		curr = curr->next;
565 		}
566 	/*
567 	 * Go through the list of used strength_bits values in descending
568 	 * order.
569 	 */
570 	for (i = max_strength_bits; i >= 0; i--)
571 		if (number_uses[i] > 0)
572 			ssl_cipher_apply_rule(0, 0, 0, 0, CIPHER_ORD, i,
573 					list, head_p, tail_p);
574 
575 	OPENSSL_free(number_uses);
576 	return(1);
577 	}
578 
579 static int ssl_cipher_process_rulestr(const char *rule_str,
580 		CIPHER_ORDER *list, CIPHER_ORDER **head_p,
581 		CIPHER_ORDER **tail_p, SSL_CIPHER **ca_list)
582 	{
583 	unsigned long algorithms, mask, algo_strength, mask_strength;
584 	const char *l, *start, *buf;
585 	int j, multi, found, rule, retval, ok, buflen;
586 	char ch;
587 
588 	retval = 1;
589 	l = rule_str;
590 	for (;;)
591 		{
592 		ch = *l;
593 
594 		if (ch == '\0')
595 			break;		/* done */
596 		if (ch == '-')
597 			{ rule = CIPHER_DEL; l++; }
598 		else if (ch == '+')
599 			{ rule = CIPHER_ORD; l++; }
600 		else if (ch == '!')
601 			{ rule = CIPHER_KILL; l++; }
602 		else if (ch == '@')
603 			{ rule = CIPHER_SPECIAL; l++; }
604 		else
605 			{ rule = CIPHER_ADD; }
606 
607 		if (ITEM_SEP(ch))
608 			{
609 			l++;
610 			continue;
611 			}
612 
613 		algorithms = mask = algo_strength = mask_strength = 0;
614 
615 		start=l;
616 		for (;;)
617 			{
618 			ch = *l;
619 			buf = l;
620 			buflen = 0;
621 #ifndef CHARSET_EBCDIC
622 			while (	((ch >= 'A') && (ch <= 'Z')) ||
623 				((ch >= '0') && (ch <= '9')) ||
624 				((ch >= 'a') && (ch <= 'z')) ||
625 				 (ch == '-'))
626 #else
627 			while (	isalnum(ch) || (ch == '-'))
628 #endif
629 				 {
630 				 ch = *(++l);
631 				 buflen++;
632 				 }
633 
634 			if (buflen == 0)
635 				{
636 				/*
637 				 * We hit something we cannot deal with,
638 				 * it is no command or separator nor
639 				 * alphanumeric, so we call this an error.
640 				 */
641 				SSLerr(SSL_F_SSL_CIPHER_PROCESS_RULESTR,
642 				       SSL_R_INVALID_COMMAND);
643 				retval = found = 0;
644 				l++;
645 				break;
646 				}
647 
648 			if (rule == CIPHER_SPECIAL)
649 				{
650 				found = 0; /* unused -- avoid compiler warning */
651 				break;	/* special treatment */
652 				}
653 
654 			/* check for multi-part specification */
655 			if (ch == '+')
656 				{
657 				multi=1;
658 				l++;
659 				}
660 			else
661 				multi=0;
662 
663 			/*
664 			 * Now search for the cipher alias in the ca_list. Be careful
665 			 * with the strncmp, because the "buflen" limitation
666 			 * will make the rule "ADH:SOME" and the cipher
667 			 * "ADH-MY-CIPHER" look like a match for buflen=3.
668 			 * So additionally check whether the cipher name found
669 			 * has the correct length. We can save a strlen() call:
670 			 * just checking for the '\0' at the right place is
671 			 * sufficient, we have to strncmp() anyway.
672 			 */
673 			 j = found = 0;
674 			 while (ca_list[j])
675 				{
676 				if ((ca_list[j]->name[buflen] == '\0') &&
677 				    !strncmp(buf, ca_list[j]->name, buflen))
678 					{
679 					found = 1;
680 					break;
681 					}
682 				else
683 					j++;
684 				}
685 			if (!found)
686 				break;	/* ignore this entry */
687 
688 			algorithms |= ca_list[j]->algorithms;
689 			mask |= ca_list[j]->mask;
690 			algo_strength |= ca_list[j]->algo_strength;
691 			mask_strength |= ca_list[j]->mask_strength;
692 
693 			if (!multi) break;
694 			}
695 
696 		/*
697 		 * Ok, we have the rule, now apply it
698 		 */
699 		if (rule == CIPHER_SPECIAL)
700 			{	/* special command */
701 			ok = 0;
702 			if ((buflen == 8) &&
703 				!strncmp(buf, "STRENGTH", 8))
704 				ok = ssl_cipher_strength_sort(list,
705 					head_p, tail_p);
706 			else
707 				SSLerr(SSL_F_SSL_CIPHER_PROCESS_RULESTR,
708 					SSL_R_INVALID_COMMAND);
709 			if (ok == 0)
710 				retval = 0;
711 			/*
712 			 * We do not support any "multi" options
713 			 * together with "@", so throw away the
714 			 * rest of the command, if any left, until
715 			 * end or ':' is found.
716 			 */
717 			while ((*l != '\0') && ITEM_SEP(*l))
718 				l++;
719 			}
720 		else if (found)
721 			{
722 			ssl_cipher_apply_rule(algorithms, mask,
723 				algo_strength, mask_strength, rule, -1,
724 				list, head_p, tail_p);
725 			}
726 		else
727 			{
728 			while ((*l != '\0') && ITEM_SEP(*l))
729 				l++;
730 			}
731 		if (*l == '\0') break; /* done */
732 		}
733 
734 	return(retval);
735 	}
736 
737 STACK_OF(SSL_CIPHER) *ssl_create_cipher_list(const SSL_METHOD *ssl_method,
738 		STACK_OF(SSL_CIPHER) **cipher_list,
739 		STACK_OF(SSL_CIPHER) **cipher_list_by_id,
740 		const char *rule_str)
741 	{
742 	int ok, num_of_ciphers, num_of_alias_max, num_of_group_aliases;
743 	unsigned long disabled_mask;
744 	STACK_OF(SSL_CIPHER) *cipherstack;
745 	const char *rule_p;
746 	CIPHER_ORDER *list = NULL, *head = NULL, *tail = NULL, *curr;
747 	SSL_CIPHER **ca_list = NULL;
748 
749 	/*
750 	 * Return with error if nothing to do.
751 	 */
752 	if (rule_str == NULL) return(NULL);
753 
754 	if (init_ciphers)
755 		{
756 		CRYPTO_w_lock(CRYPTO_LOCK_SSL);
757 		if (init_ciphers) load_ciphers();
758 		CRYPTO_w_unlock(CRYPTO_LOCK_SSL);
759 		}
760 
761 	/*
762 	 * To reduce the work to do we only want to process the compiled
763 	 * in algorithms, so we first get the mask of disabled ciphers.
764 	 */
765 	disabled_mask = ssl_cipher_get_disabled();
766 
767 	/*
768 	 * Now we have to collect the available ciphers from the compiled
769 	 * in ciphers. We cannot get more than the number compiled in, so
770 	 * it is used for allocation.
771 	 */
772 	num_of_ciphers = ssl_method->num_ciphers();
773 #ifdef KSSL_DEBUG
774 	printf("ssl_create_cipher_list() for %d ciphers\n", num_of_ciphers);
775 #endif    /* KSSL_DEBUG */
776 	list = (CIPHER_ORDER *)OPENSSL_malloc(sizeof(CIPHER_ORDER) * num_of_ciphers);
777 	if (list == NULL)
778 		{
779 		SSLerr(SSL_F_SSL_CREATE_CIPHER_LIST,ERR_R_MALLOC_FAILURE);
780 		return(NULL);	/* Failure */
781 		}
782 
783 	ssl_cipher_collect_ciphers(ssl_method, num_of_ciphers, disabled_mask,
784 				   list, &head, &tail);
785 
786 	/*
787 	 * We also need cipher aliases for selecting based on the rule_str.
788 	 * There might be two types of entries in the rule_str: 1) names
789 	 * of ciphers themselves 2) aliases for groups of ciphers.
790 	 * For 1) we need the available ciphers and for 2) the cipher
791 	 * groups of cipher_aliases added together in one list (otherwise
792 	 * we would be happy with just the cipher_aliases table).
793 	 */
794 	num_of_group_aliases = sizeof(cipher_aliases) / sizeof(SSL_CIPHER);
795 	num_of_alias_max = num_of_ciphers + num_of_group_aliases + 1;
796 	ca_list =
797 		(SSL_CIPHER **)OPENSSL_malloc(sizeof(SSL_CIPHER *) * num_of_alias_max);
798 	if (ca_list == NULL)
799 		{
800 		OPENSSL_free(list);
801 		SSLerr(SSL_F_SSL_CREATE_CIPHER_LIST,ERR_R_MALLOC_FAILURE);
802 		return(NULL);	/* Failure */
803 		}
804 	ssl_cipher_collect_aliases(ca_list, num_of_group_aliases, disabled_mask,
805 				   head);
806 
807 	/*
808 	 * If the rule_string begins with DEFAULT, apply the default rule
809 	 * before using the (possibly available) additional rules.
810 	 */
811 	ok = 1;
812 	rule_p = rule_str;
813 	if (strncmp(rule_str,"DEFAULT",7) == 0)
814 		{
815 		ok = ssl_cipher_process_rulestr(SSL_DEFAULT_CIPHER_LIST,
816 			list, &head, &tail, ca_list);
817 		rule_p += 7;
818 		if (*rule_p == ':')
819 			rule_p++;
820 		}
821 
822 	if (ok && (strlen(rule_p) > 0))
823 		ok = ssl_cipher_process_rulestr(rule_p, list, &head, &tail,
824 						ca_list);
825 
826 	OPENSSL_free(ca_list);	/* Not needed anymore */
827 
828 	if (!ok)
829 		{	/* Rule processing failure */
830 		OPENSSL_free(list);
831 		return(NULL);
832 		}
833 	/*
834 	 * Allocate new "cipherstack" for the result, return with error
835 	 * if we cannot get one.
836 	 */
837 	if ((cipherstack = sk_SSL_CIPHER_new_null()) == NULL)
838 		{
839 		OPENSSL_free(list);
840 		return(NULL);
841 		}
842 
843 	/*
844 	 * The cipher selection for the list is done. The ciphers are added
845 	 * to the resulting precedence to the STACK_OF(SSL_CIPHER).
846 	 */
847 	for (curr = head; curr != NULL; curr = curr->next)
848 		{
849 		if (curr->active)
850 			{
851 			sk_SSL_CIPHER_push(cipherstack, curr->cipher);
852 #ifdef CIPHER_DEBUG
853 			printf("<%s>\n",curr->cipher->name);
854 #endif
855 			}
856 		}
857 	OPENSSL_free(list);	/* Not needed any longer */
858 
859 	/*
860 	 * The following passage is a little bit odd. If pointer variables
861 	 * were supplied to hold STACK_OF(SSL_CIPHER) return information,
862 	 * the old memory pointed to is free()ed. Then, however, the
863 	 * cipher_list entry will be assigned just a copy of the returned
864 	 * cipher stack. For cipher_list_by_id a copy of the cipher stack
865 	 * will be created. See next comment...
866 	 */
867 	if (cipher_list != NULL)
868 		{
869 		if (*cipher_list != NULL)
870 			sk_SSL_CIPHER_free(*cipher_list);
871 		*cipher_list = cipherstack;
872 		}
873 
874 	if (cipher_list_by_id != NULL)
875 		{
876 		if (*cipher_list_by_id != NULL)
877 			sk_SSL_CIPHER_free(*cipher_list_by_id);
878 		*cipher_list_by_id = sk_SSL_CIPHER_dup(cipherstack);
879 		}
880 
881 	/*
882 	 * Now it is getting really strange. If something failed during
883 	 * the previous pointer assignment or if one of the pointers was
884 	 * not requested, the error condition is met. That might be
885 	 * discussable. The strange thing is however that in this case
886 	 * the memory "ret" pointed to is "free()ed" and hence the pointer
887 	 * cipher_list becomes wild. The memory reserved for
888 	 * cipher_list_by_id however is not "free()ed" and stays intact.
889 	 */
890 	if (	(cipher_list_by_id == NULL) ||
891 		(*cipher_list_by_id == NULL) ||
892 		(cipher_list == NULL) ||
893 		(*cipher_list == NULL))
894 		{
895 		sk_SSL_CIPHER_free(cipherstack);
896 		return(NULL);
897 		}
898 
899 	sk_SSL_CIPHER_set_cmp_func(*cipher_list_by_id,ssl_cipher_ptr_id_cmp);
900 
901 	return(cipherstack);
902 	}
903 
904 char *SSL_CIPHER_description(SSL_CIPHER *cipher, char *buf, int len)
905 	{
906 	int is_export,pkl,kl;
907 	char *ver,*exp;
908 	char *kx,*au,*enc,*mac;
909 	unsigned long alg,alg2,alg_s;
910 #ifdef KSSL_DEBUG
911 	static char *format="%-23s %s Kx=%-8s Au=%-4s Enc=%-9s Mac=%-4s%s AL=%lx\n";
912 #else
913 	static char *format="%-23s %s Kx=%-8s Au=%-4s Enc=%-9s Mac=%-4s%s\n";
914 #endif /* KSSL_DEBUG */
915 
916 	alg=cipher->algorithms;
917 	alg_s=cipher->algo_strength;
918 	alg2=cipher->algorithm2;
919 
920 	is_export=SSL_C_IS_EXPORT(cipher);
921 	pkl=SSL_C_EXPORT_PKEYLENGTH(cipher);
922 	kl=SSL_C_EXPORT_KEYLENGTH(cipher);
923 	exp=is_export?" export":"";
924 
925 	if (alg & SSL_SSLV2)
926 		ver="SSLv2";
927 	else if (alg & SSL_SSLV3)
928 		ver="SSLv3";
929 	else
930 		ver="unknown";
931 
932 	switch (alg&SSL_MKEY_MASK)
933 		{
934 	case SSL_kRSA:
935 		kx=is_export?(pkl == 512 ? "RSA(512)" : "RSA(1024)"):"RSA";
936 		break;
937 	case SSL_kDHr:
938 		kx="DH/RSA";
939 		break;
940 	case SSL_kDHd:
941 		kx="DH/DSS";
942 		break;
943         case SSL_kKRB5:         /* VRS */
944         case SSL_KRB5:          /* VRS */
945             kx="KRB5";
946             break;
947 	case SSL_kFZA:
948 		kx="Fortezza";
949 		break;
950 	case SSL_kEDH:
951 		kx=is_export?(pkl == 512 ? "DH(512)" : "DH(1024)"):"DH";
952 		break;
953 	default:
954 		kx="unknown";
955 		}
956 
957 	switch (alg&SSL_AUTH_MASK)
958 		{
959 	case SSL_aRSA:
960 		au="RSA";
961 		break;
962 	case SSL_aDSS:
963 		au="DSS";
964 		break;
965 	case SSL_aDH:
966 		au="DH";
967 		break;
968         case SSL_aKRB5:         /* VRS */
969         case SSL_KRB5:          /* VRS */
970             au="KRB5";
971             break;
972 	case SSL_aFZA:
973 	case SSL_aNULL:
974 		au="None";
975 		break;
976 	default:
977 		au="unknown";
978 		break;
979 		}
980 
981 	switch (alg&SSL_ENC_MASK)
982 		{
983 	case SSL_DES:
984 		enc=(is_export && kl == 5)?"DES(40)":"DES(56)";
985 		break;
986 	case SSL_3DES:
987 		enc="3DES(168)";
988 		break;
989 	case SSL_RC4:
990 		enc=is_export?(kl == 5 ? "RC4(40)" : "RC4(56)")
991 		  :((alg2&SSL2_CF_8_BYTE_ENC)?"RC4(64)":"RC4(128)");
992 		break;
993 	case SSL_RC2:
994 		enc=is_export?(kl == 5 ? "RC2(40)" : "RC2(56)"):"RC2(128)";
995 		break;
996 	case SSL_IDEA:
997 		enc="IDEA(128)";
998 		break;
999 	case SSL_eFZA:
1000 		enc="Fortezza";
1001 		break;
1002 	case SSL_eNULL:
1003 		enc="None";
1004 		break;
1005 	case SSL_AES:
1006 		switch(cipher->strength_bits)
1007 			{
1008 		case 128: enc="AES(128)"; break;
1009 		case 192: enc="AES(192)"; break;
1010 		case 256: enc="AES(256)"; break;
1011 		default: enc="AES(?""?""?)"; break;
1012 			}
1013 		break;
1014 	default:
1015 		enc="unknown";
1016 		break;
1017 		}
1018 
1019 	switch (alg&SSL_MAC_MASK)
1020 		{
1021 	case SSL_MD5:
1022 		mac="MD5";
1023 		break;
1024 	case SSL_SHA1:
1025 		mac="SHA1";
1026 		break;
1027 	default:
1028 		mac="unknown";
1029 		break;
1030 		}
1031 
1032 	if (buf == NULL)
1033 		{
1034 		len=128;
1035 		buf=OPENSSL_malloc(len);
1036 		if (buf == NULL) return("OPENSSL_malloc Error");
1037 		}
1038 	else if (len < 128)
1039 		return("Buffer too small");
1040 
1041 #ifdef KSSL_DEBUG
1042 	BIO_snprintf(buf,len,format,cipher->name,ver,kx,au,enc,mac,exp,alg);
1043 #else
1044 	BIO_snprintf(buf,len,format,cipher->name,ver,kx,au,enc,mac,exp);
1045 #endif /* KSSL_DEBUG */
1046 	return(buf);
1047 	}
1048 
1049 char *SSL_CIPHER_get_version(SSL_CIPHER *c)
1050 	{
1051 	int i;
1052 
1053 	if (c == NULL) return("(NONE)");
1054 	i=(int)(c->id>>24L);
1055 	if (i == 3)
1056 		return("TLSv1/SSLv3");
1057 	else if (i == 2)
1058 		return("SSLv2");
1059 	else
1060 		return("unknown");
1061 	}
1062 
1063 /* return the actual cipher being used */
1064 const char *SSL_CIPHER_get_name(SSL_CIPHER *c)
1065 	{
1066 	if (c != NULL)
1067 		return(c->name);
1068 	return("(NONE)");
1069 	}
1070 
1071 /* number of bits for symmetric cipher */
1072 int SSL_CIPHER_get_bits(SSL_CIPHER *c, int *alg_bits)
1073 	{
1074 	int ret=0;
1075 
1076 	if (c != NULL)
1077 		{
1078 		if (alg_bits != NULL) *alg_bits = c->alg_bits;
1079 		ret = c->strength_bits;
1080 		}
1081 	return(ret);
1082 	}
1083 
1084 SSL_COMP *ssl3_comp_find(STACK_OF(SSL_COMP) *sk, int n)
1085 	{
1086 	SSL_COMP *ctmp;
1087 	int i,nn;
1088 
1089 	if ((n == 0) || (sk == NULL)) return(NULL);
1090 	nn=sk_SSL_COMP_num(sk);
1091 	for (i=0; i<nn; i++)
1092 		{
1093 		ctmp=sk_SSL_COMP_value(sk,i);
1094 		if (ctmp->id == n)
1095 			return(ctmp);
1096 		}
1097 	return(NULL);
1098 	}
1099 
1100 static int sk_comp_cmp(const SSL_COMP * const *a,
1101 			const SSL_COMP * const *b)
1102 	{
1103 	return((*a)->id-(*b)->id);
1104 	}
1105 
1106 STACK_OF(SSL_COMP) *SSL_COMP_get_compression_methods(void)
1107 	{
1108 	return(ssl_comp_methods);
1109 	}
1110 
1111 int SSL_COMP_add_compression_method(int id, COMP_METHOD *cm)
1112 	{
1113 	SSL_COMP *comp;
1114 	STACK_OF(SSL_COMP) *sk;
1115 
1116         if (cm == NULL || cm->type == NID_undef)
1117                 return 1;
1118 
1119 	MemCheck_off();
1120 	comp=(SSL_COMP *)OPENSSL_malloc(sizeof(SSL_COMP));
1121 	comp->id=id;
1122 	comp->method=cm;
1123 	if (ssl_comp_methods == NULL)
1124 		sk=ssl_comp_methods=sk_SSL_COMP_new(sk_comp_cmp);
1125 	else
1126 		sk=ssl_comp_methods;
1127 	if ((sk == NULL) || !sk_SSL_COMP_push(sk,comp))
1128 		{
1129 		MemCheck_on();
1130 		SSLerr(SSL_F_SSL_COMP_ADD_COMPRESSION_METHOD,ERR_R_MALLOC_FAILURE);
1131 		return(0);
1132 		}
1133 	else
1134 		{
1135 		MemCheck_on();
1136 		return(1);
1137 		}
1138 	}
1139