xref: /openbsd-src/lib/libssl/ssl_ciph.c (revision ce7e0fc6a9d74d25b78fb6ad846387717f5172b6)
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 	 * Similarly, don't include AES in ALL because these ciphers are not yet official. */
105 	{0,SSL_TXT_ALL, 0,SSL_ALL & ~SSL_eNULL & ~SSL_AES, SSL_ALL ,0,0,0,SSL_ALL,SSL_ALL}, /* must be first */
106         {0,SSL_TXT_kKRB5,0,SSL_kKRB5,0,0,0,0,SSL_MKEY_MASK,0},  /* VRS Kerberos5 */
107 	{0,SSL_TXT_kRSA,0,SSL_kRSA,  0,0,0,0,SSL_MKEY_MASK,0},
108 	{0,SSL_TXT_kDHr,0,SSL_kDHr,  0,0,0,0,SSL_MKEY_MASK,0},
109 	{0,SSL_TXT_kDHd,0,SSL_kDHd,  0,0,0,0,SSL_MKEY_MASK,0},
110 	{0,SSL_TXT_kEDH,0,SSL_kEDH,  0,0,0,0,SSL_MKEY_MASK,0},
111 	{0,SSL_TXT_kFZA,0,SSL_kFZA,  0,0,0,0,SSL_MKEY_MASK,0},
112 	{0,SSL_TXT_DH,	0,SSL_DH,    0,0,0,0,SSL_MKEY_MASK,0},
113 	{0,SSL_TXT_EDH,	0,SSL_EDH,   0,0,0,0,SSL_MKEY_MASK|SSL_AUTH_MASK,0},
114 
115 	{0,SSL_TXT_aKRB5,0,SSL_aKRB5,0,0,0,0,SSL_AUTH_MASK,0},  /* VRS Kerberos5 */
116 	{0,SSL_TXT_aRSA,0,SSL_aRSA,  0,0,0,0,SSL_AUTH_MASK,0},
117 	{0,SSL_TXT_aDSS,0,SSL_aDSS,  0,0,0,0,SSL_AUTH_MASK,0},
118 	{0,SSL_TXT_aFZA,0,SSL_aFZA,  0,0,0,0,SSL_AUTH_MASK,0},
119 	{0,SSL_TXT_aNULL,0,SSL_aNULL,0,0,0,0,SSL_AUTH_MASK,0},
120 	{0,SSL_TXT_aDH, 0,SSL_aDH,   0,0,0,0,SSL_AUTH_MASK,0},
121 	{0,SSL_TXT_DSS,	0,SSL_DSS,   0,0,0,0,SSL_AUTH_MASK,0},
122 
123 	{0,SSL_TXT_DES,	0,SSL_DES,   0,0,0,0,SSL_ENC_MASK,0},
124 	{0,SSL_TXT_3DES,0,SSL_3DES,  0,0,0,0,SSL_ENC_MASK,0},
125 	{0,SSL_TXT_RC4,	0,SSL_RC4,   0,0,0,0,SSL_ENC_MASK,0},
126 	{0,SSL_TXT_RC2,	0,SSL_RC2,   0,0,0,0,SSL_ENC_MASK,0},
127 	{0,SSL_TXT_IDEA,0,SSL_IDEA,  0,0,0,0,SSL_ENC_MASK,0},
128 	{0,SSL_TXT_eNULL,0,SSL_eNULL,0,0,0,0,SSL_ENC_MASK,0},
129 	{0,SSL_TXT_eFZA,0,SSL_eFZA,  0,0,0,0,SSL_ENC_MASK,0},
130 	{0,SSL_TXT_AES,	0,SSL_AES,   0,0,0,0,SSL_ENC_MASK,0},
131 
132 	{0,SSL_TXT_MD5,	0,SSL_MD5,   0,0,0,0,SSL_MAC_MASK,0},
133 	{0,SSL_TXT_SHA1,0,SSL_SHA1,  0,0,0,0,SSL_MAC_MASK,0},
134 	{0,SSL_TXT_SHA,	0,SSL_SHA,   0,0,0,0,SSL_MAC_MASK,0},
135 
136 	{0,SSL_TXT_NULL,0,SSL_NULL,  0,0,0,0,SSL_ENC_MASK,0},
137 	{0,SSL_TXT_KRB5,0,SSL_KRB5,  0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK,0},
138 	{0,SSL_TXT_RSA,	0,SSL_RSA,   0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK,0},
139 	{0,SSL_TXT_ADH,	0,SSL_ADH,   0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK,0},
140 	{0,SSL_TXT_FZA,	0,SSL_FZA,   0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK|SSL_ENC_MASK,0},
141 
142 	{0,SSL_TXT_SSLV2, 0,SSL_SSLV2, 0,0,0,0,SSL_SSL_MASK,0},
143 	{0,SSL_TXT_SSLV3, 0,SSL_SSLV3, 0,0,0,0,SSL_SSL_MASK,0},
144 	{0,SSL_TXT_TLSV1, 0,SSL_TLSV1, 0,0,0,0,SSL_SSL_MASK,0},
145 
146 	{0,SSL_TXT_EXP   ,0, 0,SSL_EXPORT, 0,0,0,0,SSL_EXP_MASK},
147 	{0,SSL_TXT_EXPORT,0, 0,SSL_EXPORT, 0,0,0,0,SSL_EXP_MASK},
148 	{0,SSL_TXT_EXP40, 0, 0, SSL_EXP40, 0,0,0,0,SSL_STRONG_MASK},
149 	{0,SSL_TXT_EXP56, 0, 0, SSL_EXP56, 0,0,0,0,SSL_STRONG_MASK},
150 	{0,SSL_TXT_LOW,   0, 0,   SSL_LOW, 0,0,0,0,SSL_STRONG_MASK},
151 	{0,SSL_TXT_MEDIUM,0, 0,SSL_MEDIUM, 0,0,0,0,SSL_STRONG_MASK},
152 	{0,SSL_TXT_HIGH,  0, 0,  SSL_HIGH, 0,0,0,0,SSL_STRONG_MASK},
153 	};
154 
155 static int init_ciphers=1;
156 
157 static void load_ciphers(void)
158 	{
159 	init_ciphers=0;
160 	ssl_cipher_methods[SSL_ENC_DES_IDX]=
161 		EVP_get_cipherbyname(SN_des_cbc);
162 	ssl_cipher_methods[SSL_ENC_3DES_IDX]=
163 		EVP_get_cipherbyname(SN_des_ede3_cbc);
164 	ssl_cipher_methods[SSL_ENC_RC4_IDX]=
165 		EVP_get_cipherbyname(SN_rc4);
166 	ssl_cipher_methods[SSL_ENC_RC2_IDX]=
167 		EVP_get_cipherbyname(SN_rc2_cbc);
168 	ssl_cipher_methods[SSL_ENC_IDEA_IDX]=
169 		EVP_get_cipherbyname(SN_idea_cbc);
170 	ssl_cipher_methods[SSL_ENC_AES128_IDX]=
171 	  EVP_get_cipherbyname(SN_aes_128_cbc);
172 	ssl_cipher_methods[SSL_ENC_AES256_IDX]=
173 	  EVP_get_cipherbyname(SN_aes_256_cbc);
174 
175 	ssl_digest_methods[SSL_MD_MD5_IDX]=
176 		EVP_get_digestbyname(SN_md5);
177 	ssl_digest_methods[SSL_MD_SHA1_IDX]=
178 		EVP_get_digestbyname(SN_sha1);
179 	}
180 
181 int ssl_cipher_get_evp(SSL_SESSION *s, const EVP_CIPHER **enc,
182 	     const EVP_MD **md, SSL_COMP **comp)
183 	{
184 	int i;
185 	SSL_CIPHER *c;
186 
187 	c=s->cipher;
188 	if (c == NULL) return(0);
189 	if (comp != NULL)
190 		{
191 		SSL_COMP ctmp;
192 
193 		if (s->compress_meth == 0)
194 			*comp=NULL;
195 		else if (ssl_comp_methods == NULL)
196 			{
197 			/* bad */
198 			*comp=NULL;
199 			}
200 		else
201 			{
202 
203 			ctmp.id=s->compress_meth;
204 			i=sk_SSL_COMP_find(ssl_comp_methods,&ctmp);
205 			if (i >= 0)
206 				*comp=sk_SSL_COMP_value(ssl_comp_methods,i);
207 			else
208 				*comp=NULL;
209 			}
210 		}
211 
212 	if ((enc == NULL) || (md == NULL)) return(0);
213 
214 	switch (c->algorithms & SSL_ENC_MASK)
215 		{
216 	case SSL_DES:
217 		i=SSL_ENC_DES_IDX;
218 		break;
219 	case SSL_3DES:
220 		i=SSL_ENC_3DES_IDX;
221 		break;
222 	case SSL_RC4:
223 		i=SSL_ENC_RC4_IDX;
224 		break;
225 	case SSL_RC2:
226 		i=SSL_ENC_RC2_IDX;
227 		break;
228 	case SSL_IDEA:
229 		i=SSL_ENC_IDEA_IDX;
230 		break;
231 	case SSL_eNULL:
232 		i=SSL_ENC_NULL_IDX;
233 		break;
234 	case SSL_AES:
235 		switch(c->alg_bits)
236 			{
237 		case 128: i=SSL_ENC_AES128_IDX; break;
238 		case 256: i=SSL_ENC_AES256_IDX; break;
239 		default: i=-1; break;
240 			}
241 		break;
242 	default:
243 		i= -1;
244 		break;
245 		}
246 
247 	if ((i < 0) || (i > SSL_ENC_NUM_IDX))
248 		*enc=NULL;
249 	else
250 		{
251 		if (i == SSL_ENC_NULL_IDX)
252 			*enc=EVP_enc_null();
253 		else
254 			*enc=ssl_cipher_methods[i];
255 		}
256 
257 	switch (c->algorithms & SSL_MAC_MASK)
258 		{
259 	case SSL_MD5:
260 		i=SSL_MD_MD5_IDX;
261 		break;
262 	case SSL_SHA1:
263 		i=SSL_MD_SHA1_IDX;
264 		break;
265 	default:
266 		i= -1;
267 		break;
268 		}
269 	if ((i < 0) || (i > SSL_MD_NUM_IDX))
270 		*md=NULL;
271 	else
272 		*md=ssl_digest_methods[i];
273 
274 	if ((*enc != NULL) && (*md != NULL))
275 		return(1);
276 	else
277 		return(0);
278 	}
279 
280 #define ITEM_SEP(a) \
281 	(((a) == ':') || ((a) == ' ') || ((a) == ';') || ((a) == ','))
282 
283 static void ll_append_tail(CIPHER_ORDER **head, CIPHER_ORDER *curr,
284 	     CIPHER_ORDER **tail)
285 	{
286 	if (curr == *tail) return;
287 	if (curr == *head)
288 		*head=curr->next;
289 	if (curr->prev != NULL)
290 		curr->prev->next=curr->next;
291 	if (curr->next != NULL) /* should always be true */
292 		curr->next->prev=curr->prev;
293 	(*tail)->next=curr;
294 	curr->prev= *tail;
295 	curr->next=NULL;
296 	*tail=curr;
297 	}
298 
299 static unsigned long ssl_cipher_get_disabled(void)
300 	{
301 	unsigned long mask;
302 
303 	mask = SSL_kFZA;
304 #ifdef OPENSSL_NO_RSA
305 	mask |= SSL_aRSA|SSL_kRSA;
306 #endif
307 #ifdef OPENSSL_NO_DSA
308 	mask |= SSL_aDSS;
309 #endif
310 #ifdef OPENSSL_NO_DH
311 	mask |= SSL_kDHr|SSL_kDHd|SSL_kEDH|SSL_aDH;
312 #endif
313 #ifdef OPENSSL_NO_KRB5
314 	mask |= SSL_kKRB5|SSL_aKRB5;
315 #endif
316 
317 #ifdef SSL_FORBID_ENULL
318 	mask |= SSL_eNULL;
319 #endif
320 
321 	mask |= (ssl_cipher_methods[SSL_ENC_DES_IDX ] == NULL) ? SSL_DES :0;
322 	mask |= (ssl_cipher_methods[SSL_ENC_3DES_IDX] == NULL) ? SSL_3DES:0;
323 	mask |= (ssl_cipher_methods[SSL_ENC_RC4_IDX ] == NULL) ? SSL_RC4 :0;
324 	mask |= (ssl_cipher_methods[SSL_ENC_RC2_IDX ] == NULL) ? SSL_RC2 :0;
325 	mask |= (ssl_cipher_methods[SSL_ENC_IDEA_IDX] == NULL) ? SSL_IDEA:0;
326 	mask |= (ssl_cipher_methods[SSL_ENC_eFZA_IDX] == NULL) ? SSL_eFZA:0;
327 	mask |= (ssl_cipher_methods[SSL_ENC_AES128_IDX] == NULL) ? SSL_AES:0;
328 
329 	mask |= (ssl_digest_methods[SSL_MD_MD5_IDX ] == NULL) ? SSL_MD5 :0;
330 	mask |= (ssl_digest_methods[SSL_MD_SHA1_IDX] == NULL) ? SSL_SHA1:0;
331 
332 	return(mask);
333 	}
334 
335 static void ssl_cipher_collect_ciphers(const SSL_METHOD *ssl_method,
336 		int num_of_ciphers, unsigned long mask, CIPHER_ORDER *list,
337 		CIPHER_ORDER **head_p, CIPHER_ORDER **tail_p)
338 	{
339 	int i, list_num;
340 	SSL_CIPHER *c;
341 
342 	/*
343 	 * We have num_of_ciphers descriptions compiled in, depending on the
344 	 * method selected (SSLv2 and/or SSLv3, TLSv1 etc).
345 	 * These will later be sorted in a linked list with at most num
346 	 * entries.
347 	 */
348 
349 	/* Get the initial list of ciphers */
350 	list_num = 0;	/* actual count of ciphers */
351 	for (i = 0; i < num_of_ciphers; i++)
352 		{
353 		c = ssl_method->get_cipher(i);
354 		/* drop those that use any of that is not available */
355 		if ((c != NULL) && c->valid && !(c->algorithms & mask))
356 			{
357 			list[list_num].cipher = c;
358 			list[list_num].next = NULL;
359 			list[list_num].prev = NULL;
360 			list[list_num].active = 0;
361 			list_num++;
362 #ifdef KSSL_DEBUG
363 			printf("\t%d: %s %lx %lx\n",i,c->name,c->id,c->algorithms);
364 #endif	/* KSSL_DEBUG */
365 			/*
366 			if (!sk_push(ca_list,(char *)c)) goto err;
367 			*/
368 			}
369 		}
370 
371 	/*
372 	 * Prepare linked list from list entries
373 	 */
374 	for (i = 1; i < list_num - 1; i++)
375 		{
376 		list[i].prev = &(list[i-1]);
377 		list[i].next = &(list[i+1]);
378 		}
379 	if (list_num > 0)
380 		{
381 		(*head_p) = &(list[0]);
382 		(*head_p)->prev = NULL;
383 		(*head_p)->next = &(list[1]);
384 		(*tail_p) = &(list[list_num - 1]);
385 		(*tail_p)->prev = &(list[list_num - 2]);
386 		(*tail_p)->next = NULL;
387 		}
388 	}
389 
390 static void ssl_cipher_collect_aliases(SSL_CIPHER **ca_list,
391 			int num_of_group_aliases, unsigned long mask,
392 			CIPHER_ORDER *head)
393 	{
394 	CIPHER_ORDER *ciph_curr;
395 	SSL_CIPHER **ca_curr;
396 	int i;
397 
398 	/*
399 	 * First, add the real ciphers as already collected
400 	 */
401 	ciph_curr = head;
402 	ca_curr = ca_list;
403 	while (ciph_curr != NULL)
404 		{
405 		*ca_curr = ciph_curr->cipher;
406 		ca_curr++;
407 		ciph_curr = ciph_curr->next;
408 		}
409 
410 	/*
411 	 * Now we add the available ones from the cipher_aliases[] table.
412 	 * They represent either an algorithm, that must be fully
413 	 * supported (not match any bit in mask) or represent a cipher
414 	 * strength value (will be added in any case because algorithms=0).
415 	 */
416 	for (i = 0; i < num_of_group_aliases; i++)
417 		{
418 		if ((i == 0) ||		/* always fetch "ALL" */
419 		    !(cipher_aliases[i].algorithms & mask))
420 			{
421 			*ca_curr = (SSL_CIPHER *)(cipher_aliases + i);
422 			ca_curr++;
423 			}
424 		}
425 
426 	*ca_curr = NULL;	/* end of list */
427 	}
428 
429 static void ssl_cipher_apply_rule(unsigned long algorithms, unsigned long mask,
430 		unsigned long algo_strength, unsigned long mask_strength,
431 		int rule, int strength_bits, CIPHER_ORDER *list,
432 		CIPHER_ORDER **head_p, CIPHER_ORDER **tail_p)
433 	{
434 	CIPHER_ORDER *head, *tail, *curr, *curr2, *tail2;
435 	SSL_CIPHER *cp;
436 	unsigned long ma, ma_s;
437 
438 #ifdef CIPHER_DEBUG
439 	printf("Applying rule %d with %08lx %08lx %08lx %08lx (%d)\n",
440 		rule, algorithms, mask, algo_strength, mask_strength,
441 		strength_bits);
442 #endif
443 
444 	curr = head = *head_p;
445 	curr2 = head;
446 	tail2 = tail = *tail_p;
447 	for (;;)
448 		{
449 		if ((curr == NULL) || (curr == tail2)) break;
450 		curr = curr2;
451 		curr2 = curr->next;
452 
453 		cp = curr->cipher;
454 
455 		/*
456 		 * Selection criteria is either the number of strength_bits
457 		 * or the algorithm used.
458 		 */
459 		if (strength_bits == -1)
460 			{
461 			ma = mask & cp->algorithms;
462 			ma_s = mask_strength & cp->algo_strength;
463 
464 #ifdef CIPHER_DEBUG
465 			printf("\nName: %s:\nAlgo = %08lx Algo_strength = %08lx\nMask = %08lx Mask_strength %08lx\n", cp->name, cp->algorithms, cp->algo_strength, mask, mask_strength);
466 			printf("ma = %08lx ma_s %08lx, ma&algo=%08lx, ma_s&algos=%08lx\n", ma, ma_s, ma&algorithms, ma_s&algo_strength);
467 #endif
468 			/*
469 			 * Select: if none of the mask bit was met from the
470 			 * cipher or not all of the bits were met, the
471 			 * selection does not apply.
472 			 */
473 			if (((ma == 0) && (ma_s == 0)) ||
474 			    ((ma & algorithms) != ma) ||
475 			    ((ma_s & algo_strength) != ma_s))
476 				continue; /* does not apply */
477 			}
478 		else if (strength_bits != cp->strength_bits)
479 			continue;	/* does not apply */
480 
481 #ifdef CIPHER_DEBUG
482 		printf("Action = %d\n", rule);
483 #endif
484 
485 		/* add the cipher if it has not been added yet. */
486 		if (rule == CIPHER_ADD)
487 			{
488 			if (!curr->active)
489 				{
490 				ll_append_tail(&head, curr, &tail);
491 				curr->active = 1;
492 				}
493 			}
494 		/* Move the added cipher to this location */
495 		else if (rule == CIPHER_ORD)
496 			{
497 			if (curr->active)
498 				{
499 				ll_append_tail(&head, curr, &tail);
500 				}
501 			}
502 		else if	(rule == CIPHER_DEL)
503 			curr->active = 0;
504 		else if (rule == CIPHER_KILL)
505 			{
506 			if (head == curr)
507 				head = curr->next;
508 			else
509 				curr->prev->next = curr->next;
510 			if (tail == curr)
511 				tail = curr->prev;
512 			curr->active = 0;
513 			if (curr->next != NULL)
514 				curr->next->prev = curr->prev;
515 			if (curr->prev != NULL)
516 				curr->prev->next = curr->next;
517 			curr->next = NULL;
518 			curr->prev = NULL;
519 			}
520 		}
521 
522 	*head_p = head;
523 	*tail_p = tail;
524 	}
525 
526 static int ssl_cipher_strength_sort(CIPHER_ORDER *list, CIPHER_ORDER **head_p,
527 				     CIPHER_ORDER **tail_p)
528 	{
529 	int max_strength_bits, i, *number_uses;
530 	CIPHER_ORDER *curr;
531 
532 	/*
533 	 * This routine sorts the ciphers with descending strength. The sorting
534 	 * must keep the pre-sorted sequence, so we apply the normal sorting
535 	 * routine as '+' movement to the end of the list.
536 	 */
537 	max_strength_bits = 0;
538 	curr = *head_p;
539 	while (curr != NULL)
540 		{
541 		if (curr->active &&
542 		    (curr->cipher->strength_bits > max_strength_bits))
543 		    max_strength_bits = curr->cipher->strength_bits;
544 		curr = curr->next;
545 		}
546 
547 	number_uses = OPENSSL_malloc((max_strength_bits + 1) * sizeof(int));
548 	if (!number_uses)
549 	{
550 		SSLerr(SSL_F_SSL_CIPHER_STRENGTH_SORT,ERR_R_MALLOC_FAILURE);
551 		return(0);
552 	}
553 	memset(number_uses, 0, (max_strength_bits + 1) * sizeof(int));
554 
555 	/*
556 	 * Now find the strength_bits values actually used
557 	 */
558 	curr = *head_p;
559 	while (curr != NULL)
560 		{
561 		if (curr->active)
562 			number_uses[curr->cipher->strength_bits]++;
563 		curr = curr->next;
564 		}
565 	/*
566 	 * Go through the list of used strength_bits values in descending
567 	 * order.
568 	 */
569 	for (i = max_strength_bits; i >= 0; i--)
570 		if (number_uses[i] > 0)
571 			ssl_cipher_apply_rule(0, 0, 0, 0, CIPHER_ORD, i,
572 					list, head_p, tail_p);
573 
574 	OPENSSL_free(number_uses);
575 	return(1);
576 	}
577 
578 static int ssl_cipher_process_rulestr(const char *rule_str,
579 		CIPHER_ORDER *list, CIPHER_ORDER **head_p,
580 		CIPHER_ORDER **tail_p, SSL_CIPHER **ca_list)
581 	{
582 	unsigned long algorithms, mask, algo_strength, mask_strength;
583 	const char *l, *start, *buf;
584 	int j, multi, found, rule, retval, ok, buflen;
585 	char ch;
586 
587 	retval = 1;
588 	l = rule_str;
589 	for (;;)
590 		{
591 		ch = *l;
592 
593 		if (ch == '\0')
594 			break;		/* done */
595 		if (ch == '-')
596 			{ rule = CIPHER_DEL; l++; }
597 		else if (ch == '+')
598 			{ rule = CIPHER_ORD; l++; }
599 		else if (ch == '!')
600 			{ rule = CIPHER_KILL; l++; }
601 		else if (ch == '@')
602 			{ rule = CIPHER_SPECIAL; l++; }
603 		else
604 			{ rule = CIPHER_ADD; }
605 
606 		if (ITEM_SEP(ch))
607 			{
608 			l++;
609 			continue;
610 			}
611 
612 		algorithms = mask = algo_strength = mask_strength = 0;
613 
614 		start=l;
615 		for (;;)
616 			{
617 			ch = *l;
618 			buf = l;
619 			buflen = 0;
620 #ifndef CHARSET_EBCDIC
621 			while (	((ch >= 'A') && (ch <= 'Z')) ||
622 				((ch >= '0') && (ch <= '9')) ||
623 				((ch >= 'a') && (ch <= 'z')) ||
624 				 (ch == '-'))
625 #else
626 			while (	isalnum(ch) || (ch == '-'))
627 #endif
628 				 {
629 				 ch = *(++l);
630 				 buflen++;
631 				 }
632 
633 			if (buflen == 0)
634 				{
635 				/*
636 				 * We hit something we cannot deal with,
637 				 * it is no command or separator nor
638 				 * alphanumeric, so we call this an error.
639 				 */
640 				SSLerr(SSL_F_SSL_CIPHER_PROCESS_RULESTR,
641 				       SSL_R_INVALID_COMMAND);
642 				retval = found = 0;
643 				l++;
644 				break;
645 				}
646 
647 			if (rule == CIPHER_SPECIAL)
648 				{
649 				found = 0; /* unused -- avoid compiler warning */
650 				break;	/* special treatment */
651 				}
652 
653 			/* check for multi-part specification */
654 			if (ch == '+')
655 				{
656 				multi=1;
657 				l++;
658 				}
659 			else
660 				multi=0;
661 
662 			/*
663 			 * Now search for the cipher alias in the ca_list. Be careful
664 			 * with the strncmp, because the "buflen" limitation
665 			 * will make the rule "ADH:SOME" and the cipher
666 			 * "ADH-MY-CIPHER" look like a match for buflen=3.
667 			 * So additionally check whether the cipher name found
668 			 * has the correct length. We can save a strlen() call:
669 			 * just checking for the '\0' at the right place is
670 			 * sufficient, we have to strncmp() anyway.
671 			 */
672 			 j = found = 0;
673 			 while (ca_list[j])
674 				{
675 				if ((ca_list[j]->name[buflen] == '\0') &&
676 				    !strncmp(buf, ca_list[j]->name, buflen))
677 					{
678 					found = 1;
679 					break;
680 					}
681 				else
682 					j++;
683 				}
684 			if (!found)
685 				break;	/* ignore this entry */
686 
687 			algorithms |= ca_list[j]->algorithms;
688 			mask |= ca_list[j]->mask;
689 			algo_strength |= ca_list[j]->algo_strength;
690 			mask_strength |= ca_list[j]->mask_strength;
691 
692 			if (!multi) break;
693 			}
694 
695 		/*
696 		 * Ok, we have the rule, now apply it
697 		 */
698 		if (rule == CIPHER_SPECIAL)
699 			{	/* special command */
700 			ok = 0;
701 			if ((buflen == 8) &&
702 				!strncmp(buf, "STRENGTH", 8))
703 				ok = ssl_cipher_strength_sort(list,
704 					head_p, tail_p);
705 			else
706 				SSLerr(SSL_F_SSL_CIPHER_PROCESS_RULESTR,
707 					SSL_R_INVALID_COMMAND);
708 			if (ok == 0)
709 				retval = 0;
710 			/*
711 			 * We do not support any "multi" options
712 			 * together with "@", so throw away the
713 			 * rest of the command, if any left, until
714 			 * end or ':' is found.
715 			 */
716 			while ((*l != '\0') && ITEM_SEP(*l))
717 				l++;
718 			}
719 		else if (found)
720 			{
721 			ssl_cipher_apply_rule(algorithms, mask,
722 				algo_strength, mask_strength, rule, -1,
723 				list, head_p, tail_p);
724 			}
725 		else
726 			{
727 			while ((*l != '\0') && ITEM_SEP(*l))
728 				l++;
729 			}
730 		if (*l == '\0') break; /* done */
731 		}
732 
733 	return(retval);
734 	}
735 
736 STACK_OF(SSL_CIPHER) *ssl_create_cipher_list(const SSL_METHOD *ssl_method,
737 		STACK_OF(SSL_CIPHER) **cipher_list,
738 		STACK_OF(SSL_CIPHER) **cipher_list_by_id,
739 		const char *rule_str)
740 	{
741 	int ok, num_of_ciphers, num_of_alias_max, num_of_group_aliases;
742 	unsigned long disabled_mask;
743 	STACK_OF(SSL_CIPHER) *cipherstack;
744 	const char *rule_p;
745 	CIPHER_ORDER *list = NULL, *head = NULL, *tail = NULL, *curr;
746 	SSL_CIPHER **ca_list = NULL;
747 
748 	/*
749 	 * Return with error if nothing to do.
750 	 */
751 	if (rule_str == NULL) return(NULL);
752 
753 	if (init_ciphers) load_ciphers();
754 
755 	/*
756 	 * To reduce the work to do we only want to process the compiled
757 	 * in algorithms, so we first get the mask of disabled ciphers.
758 	 */
759 	disabled_mask = ssl_cipher_get_disabled();
760 
761 	/*
762 	 * Now we have to collect the available ciphers from the compiled
763 	 * in ciphers. We cannot get more than the number compiled in, so
764 	 * it is used for allocation.
765 	 */
766 	num_of_ciphers = ssl_method->num_ciphers();
767 #ifdef KSSL_DEBUG
768 	printf("ssl_create_cipher_list() for %d ciphers\n", num_of_ciphers);
769 #endif    /* KSSL_DEBUG */
770 	list = (CIPHER_ORDER *)OPENSSL_malloc(sizeof(CIPHER_ORDER) * num_of_ciphers);
771 	if (list == NULL)
772 		{
773 		SSLerr(SSL_F_SSL_CREATE_CIPHER_LIST,ERR_R_MALLOC_FAILURE);
774 		return(NULL);	/* Failure */
775 		}
776 
777 	ssl_cipher_collect_ciphers(ssl_method, num_of_ciphers, disabled_mask,
778 				   list, &head, &tail);
779 
780 	/*
781 	 * We also need cipher aliases for selecting based on the rule_str.
782 	 * There might be two types of entries in the rule_str: 1) names
783 	 * of ciphers themselves 2) aliases for groups of ciphers.
784 	 * For 1) we need the available ciphers and for 2) the cipher
785 	 * groups of cipher_aliases added together in one list (otherwise
786 	 * we would be happy with just the cipher_aliases table).
787 	 */
788 	num_of_group_aliases = sizeof(cipher_aliases) / sizeof(SSL_CIPHER);
789 	num_of_alias_max = num_of_ciphers + num_of_group_aliases + 1;
790 	ca_list =
791 		(SSL_CIPHER **)OPENSSL_malloc(sizeof(SSL_CIPHER *) * num_of_alias_max);
792 	if (ca_list == NULL)
793 		{
794 		OPENSSL_free(list);
795 		SSLerr(SSL_F_SSL_CREATE_CIPHER_LIST,ERR_R_MALLOC_FAILURE);
796 		return(NULL);	/* Failure */
797 		}
798 	ssl_cipher_collect_aliases(ca_list, num_of_group_aliases, disabled_mask,
799 				   head);
800 
801 	/*
802 	 * If the rule_string begins with DEFAULT, apply the default rule
803 	 * before using the (possibly available) additional rules.
804 	 */
805 	ok = 1;
806 	rule_p = rule_str;
807 	if (strncmp(rule_str,"DEFAULT",7) == 0)
808 		{
809 		ok = ssl_cipher_process_rulestr(SSL_DEFAULT_CIPHER_LIST,
810 			list, &head, &tail, ca_list);
811 		rule_p += 7;
812 		if (*rule_p == ':')
813 			rule_p++;
814 		}
815 
816 	if (ok && (strlen(rule_p) > 0))
817 		ok = ssl_cipher_process_rulestr(rule_p, list, &head, &tail,
818 						ca_list);
819 
820 	OPENSSL_free(ca_list);	/* Not needed anymore */
821 
822 	if (!ok)
823 		{	/* Rule processing failure */
824 		OPENSSL_free(list);
825 		return(NULL);
826 		}
827 	/*
828 	 * Allocate new "cipherstack" for the result, return with error
829 	 * if we cannot get one.
830 	 */
831 	if ((cipherstack = sk_SSL_CIPHER_new_null()) == NULL)
832 		{
833 		OPENSSL_free(list);
834 		return(NULL);
835 		}
836 
837 	/*
838 	 * The cipher selection for the list is done. The ciphers are added
839 	 * to the resulting precedence to the STACK_OF(SSL_CIPHER).
840 	 */
841 	for (curr = head; curr != NULL; curr = curr->next)
842 		{
843 		if (curr->active)
844 			{
845 			sk_SSL_CIPHER_push(cipherstack, curr->cipher);
846 #ifdef CIPHER_DEBUG
847 			printf("<%s>\n",curr->cipher->name);
848 #endif
849 			}
850 		}
851 	OPENSSL_free(list);	/* Not needed any longer */
852 
853 	/*
854 	 * The following passage is a little bit odd. If pointer variables
855 	 * were supplied to hold STACK_OF(SSL_CIPHER) return information,
856 	 * the old memory pointed to is free()ed. Then, however, the
857 	 * cipher_list entry will be assigned just a copy of the returned
858 	 * cipher stack. For cipher_list_by_id a copy of the cipher stack
859 	 * will be created. See next comment...
860 	 */
861 	if (cipher_list != NULL)
862 		{
863 		if (*cipher_list != NULL)
864 			sk_SSL_CIPHER_free(*cipher_list);
865 		*cipher_list = cipherstack;
866 		}
867 
868 	if (cipher_list_by_id != NULL)
869 		{
870 		if (*cipher_list_by_id != NULL)
871 			sk_SSL_CIPHER_free(*cipher_list_by_id);
872 		*cipher_list_by_id = sk_SSL_CIPHER_dup(cipherstack);
873 		}
874 
875 	/*
876 	 * Now it is getting really strange. If something failed during
877 	 * the previous pointer assignment or if one of the pointers was
878 	 * not requested, the error condition is met. That might be
879 	 * discussable. The strange thing is however that in this case
880 	 * the memory "ret" pointed to is "free()ed" and hence the pointer
881 	 * cipher_list becomes wild. The memory reserved for
882 	 * cipher_list_by_id however is not "free()ed" and stays intact.
883 	 */
884 	if (	(cipher_list_by_id == NULL) ||
885 		(*cipher_list_by_id == NULL) ||
886 		(cipher_list == NULL) ||
887 		(*cipher_list == NULL))
888 		{
889 		sk_SSL_CIPHER_free(cipherstack);
890 		return(NULL);
891 		}
892 
893 	sk_SSL_CIPHER_set_cmp_func(*cipher_list_by_id,ssl_cipher_ptr_id_cmp);
894 
895 	return(cipherstack);
896 	}
897 
898 char *SSL_CIPHER_description(SSL_CIPHER *cipher, char *buf, int len)
899 	{
900 	int is_export,pkl,kl;
901 	char *ver,*exp;
902 	char *kx,*au,*enc,*mac;
903 	unsigned long alg,alg2,alg_s;
904 #ifdef KSSL_DEBUG
905 	static char *format="%-23s %s Kx=%-8s Au=%-4s Enc=%-9s Mac=%-4s%s AL=%lx\n";
906 #else
907 	static char *format="%-23s %s Kx=%-8s Au=%-4s Enc=%-9s Mac=%-4s%s\n";
908 #endif /* KSSL_DEBUG */
909 
910 	alg=cipher->algorithms;
911 	alg_s=cipher->algo_strength;
912 	alg2=cipher->algorithm2;
913 
914 	is_export=SSL_C_IS_EXPORT(cipher);
915 	pkl=SSL_C_EXPORT_PKEYLENGTH(cipher);
916 	kl=SSL_C_EXPORT_KEYLENGTH(cipher);
917 	exp=is_export?" export":"";
918 
919 	if (alg & SSL_SSLV2)
920 		ver="SSLv2";
921 	else if (alg & SSL_SSLV3)
922 		ver="SSLv3";
923 	else
924 		ver="unknown";
925 
926 	switch (alg&SSL_MKEY_MASK)
927 		{
928 	case SSL_kRSA:
929 		kx=is_export?(pkl == 512 ? "RSA(512)" : "RSA(1024)"):"RSA";
930 		break;
931 	case SSL_kDHr:
932 		kx="DH/RSA";
933 		break;
934 	case SSL_kDHd:
935 		kx="DH/DSS";
936 		break;
937         case SSL_kKRB5:         /* VRS */
938         case SSL_KRB5:          /* VRS */
939             kx="KRB5";
940             break;
941 	case SSL_kFZA:
942 		kx="Fortezza";
943 		break;
944 	case SSL_kEDH:
945 		kx=is_export?(pkl == 512 ? "DH(512)" : "DH(1024)"):"DH";
946 		break;
947 	default:
948 		kx="unknown";
949 		}
950 
951 	switch (alg&SSL_AUTH_MASK)
952 		{
953 	case SSL_aRSA:
954 		au="RSA";
955 		break;
956 	case SSL_aDSS:
957 		au="DSS";
958 		break;
959 	case SSL_aDH:
960 		au="DH";
961 		break;
962         case SSL_aKRB5:         /* VRS */
963         case SSL_KRB5:          /* VRS */
964             au="KRB5";
965             break;
966 	case SSL_aFZA:
967 	case SSL_aNULL:
968 		au="None";
969 		break;
970 	default:
971 		au="unknown";
972 		break;
973 		}
974 
975 	switch (alg&SSL_ENC_MASK)
976 		{
977 	case SSL_DES:
978 		enc=(is_export && kl == 5)?"DES(40)":"DES(56)";
979 		break;
980 	case SSL_3DES:
981 		enc="3DES(168)";
982 		break;
983 	case SSL_RC4:
984 		enc=is_export?(kl == 5 ? "RC4(40)" : "RC4(56)")
985 		  :((alg2&SSL2_CF_8_BYTE_ENC)?"RC4(64)":"RC4(128)");
986 		break;
987 	case SSL_RC2:
988 		enc=is_export?(kl == 5 ? "RC2(40)" : "RC2(56)"):"RC2(128)";
989 		break;
990 	case SSL_IDEA:
991 		enc="IDEA(128)";
992 		break;
993 	case SSL_eFZA:
994 		enc="Fortezza";
995 		break;
996 	case SSL_eNULL:
997 		enc="None";
998 		break;
999 	case SSL_AES:
1000 		switch(cipher->strength_bits)
1001 			{
1002 		case 128: enc="AESdraft(128)"; break;
1003 		case 192: enc="AESdraft(192)"; break;
1004 		case 256: enc="AESdraft(256)"; break;
1005 		default: enc="AESdraft(?""?""?)"; break;
1006 			}
1007 		break;
1008 	default:
1009 		enc="unknown";
1010 		break;
1011 		}
1012 
1013 	switch (alg&SSL_MAC_MASK)
1014 		{
1015 	case SSL_MD5:
1016 		mac="MD5";
1017 		break;
1018 	case SSL_SHA1:
1019 		mac="SHA1";
1020 		break;
1021 	default:
1022 		mac="unknown";
1023 		break;
1024 		}
1025 
1026 	if (buf == NULL)
1027 		{
1028 		len=128;
1029 		buf=OPENSSL_malloc(len);
1030 		if (buf == NULL) return("OPENSSL_malloc Error");
1031 		}
1032 	else if (len < 128)
1033 		return("Buffer too small");
1034 
1035 #ifdef KSSL_DEBUG
1036 	BIO_snprintf(buf,len,format,cipher->name,ver,kx,au,enc,mac,exp,alg);
1037 #else
1038 	BIO_snprintf(buf,len,format,cipher->name,ver,kx,au,enc,mac,exp);
1039 #endif /* KSSL_DEBUG */
1040 	return(buf);
1041 	}
1042 
1043 char *SSL_CIPHER_get_version(SSL_CIPHER *c)
1044 	{
1045 	int i;
1046 
1047 	if (c == NULL) return("(NONE)");
1048 	i=(int)(c->id>>24L);
1049 	if (i == 3)
1050 		return("TLSv1/SSLv3");
1051 	else if (i == 2)
1052 		return("SSLv2");
1053 	else
1054 		return("unknown");
1055 	}
1056 
1057 /* return the actual cipher being used */
1058 const char *SSL_CIPHER_get_name(SSL_CIPHER *c)
1059 	{
1060 	if (c != NULL)
1061 		return(c->name);
1062 	return("(NONE)");
1063 	}
1064 
1065 /* number of bits for symmetric cipher */
1066 int SSL_CIPHER_get_bits(SSL_CIPHER *c, int *alg_bits)
1067 	{
1068 	int ret=0;
1069 
1070 	if (c != NULL)
1071 		{
1072 		if (alg_bits != NULL) *alg_bits = c->alg_bits;
1073 		ret = c->strength_bits;
1074 		}
1075 	return(ret);
1076 	}
1077 
1078 SSL_COMP *ssl3_comp_find(STACK_OF(SSL_COMP) *sk, int n)
1079 	{
1080 	SSL_COMP *ctmp;
1081 	int i,nn;
1082 
1083 	if ((n == 0) || (sk == NULL)) return(NULL);
1084 	nn=sk_SSL_COMP_num(sk);
1085 	for (i=0; i<nn; i++)
1086 		{
1087 		ctmp=sk_SSL_COMP_value(sk,i);
1088 		if (ctmp->id == n)
1089 			return(ctmp);
1090 		}
1091 	return(NULL);
1092 	}
1093 
1094 static int sk_comp_cmp(const SSL_COMP * const *a,
1095 			const SSL_COMP * const *b)
1096 	{
1097 	return((*a)->id-(*b)->id);
1098 	}
1099 
1100 STACK_OF(SSL_COMP) *SSL_COMP_get_compression_methods(void)
1101 	{
1102 	return(ssl_comp_methods);
1103 	}
1104 
1105 int SSL_COMP_add_compression_method(int id, COMP_METHOD *cm)
1106 	{
1107 	SSL_COMP *comp;
1108 	STACK_OF(SSL_COMP) *sk;
1109 
1110         if (cm == NULL || cm->type == NID_undef)
1111                 return 1;
1112 
1113 	MemCheck_off();
1114 	comp=(SSL_COMP *)OPENSSL_malloc(sizeof(SSL_COMP));
1115 	comp->id=id;
1116 	comp->method=cm;
1117 	if (ssl_comp_methods == NULL)
1118 		sk=ssl_comp_methods=sk_SSL_COMP_new(sk_comp_cmp);
1119 	else
1120 		sk=ssl_comp_methods;
1121 	if ((sk == NULL) || !sk_SSL_COMP_push(sk,comp))
1122 		{
1123 		MemCheck_on();
1124 		SSLerr(SSL_F_SSL_COMP_ADD_COMPRESSION_METHOD,ERR_R_MALLOC_FAILURE);
1125 		return(0);
1126 		}
1127 	else
1128 		{
1129 		MemCheck_on();
1130 		return(1);
1131 		}
1132 	}
1133