xref: /openbsd/lib/libssl/ssl_ciph.c (revision db3296cf)
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 #ifndef OPENSSL_NO_IDEA
129 	{0,SSL_TXT_IDEA,0,SSL_IDEA,  0,0,0,0,SSL_ENC_MASK,0},
130 #endif
131 	{0,SSL_TXT_eNULL,0,SSL_eNULL,0,0,0,0,SSL_ENC_MASK,0},
132 	{0,SSL_TXT_eFZA,0,SSL_eFZA,  0,0,0,0,SSL_ENC_MASK,0},
133 	{0,SSL_TXT_AES,	0,SSL_AES,   0,0,0,0,SSL_ENC_MASK,0},
134 
135 	{0,SSL_TXT_MD5,	0,SSL_MD5,   0,0,0,0,SSL_MAC_MASK,0},
136 	{0,SSL_TXT_SHA1,0,SSL_SHA1,  0,0,0,0,SSL_MAC_MASK,0},
137 	{0,SSL_TXT_SHA,	0,SSL_SHA,   0,0,0,0,SSL_MAC_MASK,0},
138 
139 	{0,SSL_TXT_NULL,0,SSL_NULL,  0,0,0,0,SSL_ENC_MASK,0},
140 	{0,SSL_TXT_KRB5,0,SSL_KRB5,  0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK,0},
141 	{0,SSL_TXT_RSA,	0,SSL_RSA,   0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK,0},
142 	{0,SSL_TXT_ADH,	0,SSL_ADH,   0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK,0},
143 	{0,SSL_TXT_FZA,	0,SSL_FZA,   0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK|SSL_ENC_MASK,0},
144 
145 	{0,SSL_TXT_SSLV2, 0,SSL_SSLV2, 0,0,0,0,SSL_SSL_MASK,0},
146 	{0,SSL_TXT_SSLV3, 0,SSL_SSLV3, 0,0,0,0,SSL_SSL_MASK,0},
147 	{0,SSL_TXT_TLSV1, 0,SSL_TLSV1, 0,0,0,0,SSL_SSL_MASK,0},
148 
149 	{0,SSL_TXT_EXP   ,0, 0,SSL_EXPORT, 0,0,0,0,SSL_EXP_MASK},
150 	{0,SSL_TXT_EXPORT,0, 0,SSL_EXPORT, 0,0,0,0,SSL_EXP_MASK},
151 	{0,SSL_TXT_EXP40, 0, 0, SSL_EXP40, 0,0,0,0,SSL_STRONG_MASK},
152 	{0,SSL_TXT_EXP56, 0, 0, SSL_EXP56, 0,0,0,0,SSL_STRONG_MASK},
153 	{0,SSL_TXT_LOW,   0, 0,   SSL_LOW, 0,0,0,0,SSL_STRONG_MASK},
154 	{0,SSL_TXT_MEDIUM,0, 0,SSL_MEDIUM, 0,0,0,0,SSL_STRONG_MASK},
155 	{0,SSL_TXT_HIGH,  0, 0,  SSL_HIGH, 0,0,0,0,SSL_STRONG_MASK},
156 	};
157 
158 static int init_ciphers=1;
159 
160 static void load_ciphers(void)
161 	{
162 	init_ciphers=0;
163 	ssl_cipher_methods[SSL_ENC_DES_IDX]=
164 		EVP_get_cipherbyname(SN_des_cbc);
165 	ssl_cipher_methods[SSL_ENC_3DES_IDX]=
166 		EVP_get_cipherbyname(SN_des_ede3_cbc);
167 	ssl_cipher_methods[SSL_ENC_RC4_IDX]=
168 		EVP_get_cipherbyname(SN_rc4);
169 	ssl_cipher_methods[SSL_ENC_RC2_IDX]=
170 		EVP_get_cipherbyname(SN_rc2_cbc);
171 #ifndef OPENSSL_NO_IDEA
172 	ssl_cipher_methods[SSL_ENC_IDEA_IDX]=
173 		EVP_get_cipherbyname(SN_idea_cbc);
174 #else
175 	ssl_cipher_methods[SSL_ENC_IDEA_IDX]= NULL;
176 #endif
177 	ssl_cipher_methods[SSL_ENC_AES128_IDX]=
178 	  EVP_get_cipherbyname(SN_aes_128_cbc);
179 	ssl_cipher_methods[SSL_ENC_AES256_IDX]=
180 	  EVP_get_cipherbyname(SN_aes_256_cbc);
181 
182 	ssl_digest_methods[SSL_MD_MD5_IDX]=
183 		EVP_get_digestbyname(SN_md5);
184 	ssl_digest_methods[SSL_MD_SHA1_IDX]=
185 		EVP_get_digestbyname(SN_sha1);
186 	}
187 
188 int ssl_cipher_get_evp(SSL_SESSION *s, const EVP_CIPHER **enc,
189 	     const EVP_MD **md, SSL_COMP **comp)
190 	{
191 	int i;
192 	SSL_CIPHER *c;
193 
194 	c=s->cipher;
195 	if (c == NULL) return(0);
196 	if (comp != NULL)
197 		{
198 		SSL_COMP ctmp;
199 
200 		if (s->compress_meth == 0)
201 			*comp=NULL;
202 		else if (ssl_comp_methods == NULL)
203 			{
204 			/* bad */
205 			*comp=NULL;
206 			}
207 		else
208 			{
209 
210 			ctmp.id=s->compress_meth;
211 			i=sk_SSL_COMP_find(ssl_comp_methods,&ctmp);
212 			if (i >= 0)
213 				*comp=sk_SSL_COMP_value(ssl_comp_methods,i);
214 			else
215 				*comp=NULL;
216 			}
217 		}
218 
219 	if ((enc == NULL) || (md == NULL)) return(0);
220 
221 	switch (c->algorithms & SSL_ENC_MASK)
222 		{
223 	case SSL_DES:
224 		i=SSL_ENC_DES_IDX;
225 		break;
226 	case SSL_3DES:
227 		i=SSL_ENC_3DES_IDX;
228 		break;
229 	case SSL_RC4:
230 		i=SSL_ENC_RC4_IDX;
231 		break;
232 	case SSL_RC2:
233 		i=SSL_ENC_RC2_IDX;
234 		break;
235 	case SSL_IDEA:
236 		i=SSL_ENC_IDEA_IDX;
237 		break;
238 	case SSL_eNULL:
239 		i=SSL_ENC_NULL_IDX;
240 		break;
241 	case SSL_AES:
242 		switch(c->alg_bits)
243 			{
244 		case 128: i=SSL_ENC_AES128_IDX; break;
245 		case 256: i=SSL_ENC_AES256_IDX; break;
246 		default: i=-1; break;
247 			}
248 		break;
249 	default:
250 		i= -1;
251 		break;
252 		}
253 
254 	if ((i < 0) || (i > SSL_ENC_NUM_IDX))
255 		*enc=NULL;
256 	else
257 		{
258 		if (i == SSL_ENC_NULL_IDX)
259 			*enc=EVP_enc_null();
260 		else
261 			*enc=ssl_cipher_methods[i];
262 		}
263 
264 	switch (c->algorithms & SSL_MAC_MASK)
265 		{
266 	case SSL_MD5:
267 		i=SSL_MD_MD5_IDX;
268 		break;
269 	case SSL_SHA1:
270 		i=SSL_MD_SHA1_IDX;
271 		break;
272 	default:
273 		i= -1;
274 		break;
275 		}
276 	if ((i < 0) || (i > SSL_MD_NUM_IDX))
277 		*md=NULL;
278 	else
279 		*md=ssl_digest_methods[i];
280 
281 	if ((*enc != NULL) && (*md != NULL))
282 		return(1);
283 	else
284 		return(0);
285 	}
286 
287 #define ITEM_SEP(a) \
288 	(((a) == ':') || ((a) == ' ') || ((a) == ';') || ((a) == ','))
289 
290 static void ll_append_tail(CIPHER_ORDER **head, CIPHER_ORDER *curr,
291 	     CIPHER_ORDER **tail)
292 	{
293 	if (curr == *tail) return;
294 	if (curr == *head)
295 		*head=curr->next;
296 	if (curr->prev != NULL)
297 		curr->prev->next=curr->next;
298 	if (curr->next != NULL) /* should always be true */
299 		curr->next->prev=curr->prev;
300 	(*tail)->next=curr;
301 	curr->prev= *tail;
302 	curr->next=NULL;
303 	*tail=curr;
304 	}
305 
306 static unsigned long ssl_cipher_get_disabled(void)
307 	{
308 	unsigned long mask;
309 
310 	mask = SSL_kFZA;
311 #ifdef OPENSSL_NO_RSA
312 	mask |= SSL_aRSA|SSL_kRSA;
313 #endif
314 #ifdef OPENSSL_NO_DSA
315 	mask |= SSL_aDSS;
316 #endif
317 #ifdef OPENSSL_NO_DH
318 	mask |= SSL_kDHr|SSL_kDHd|SSL_kEDH|SSL_aDH;
319 #endif
320 #ifdef OPENSSL_NO_KRB5
321 	mask |= SSL_kKRB5|SSL_aKRB5;
322 #endif
323 
324 #ifdef SSL_FORBID_ENULL
325 	mask |= SSL_eNULL;
326 #endif
327 
328 	mask |= (ssl_cipher_methods[SSL_ENC_DES_IDX ] == NULL) ? SSL_DES :0;
329 	mask |= (ssl_cipher_methods[SSL_ENC_3DES_IDX] == NULL) ? SSL_3DES:0;
330 	mask |= (ssl_cipher_methods[SSL_ENC_RC4_IDX ] == NULL) ? SSL_RC4 :0;
331 	mask |= (ssl_cipher_methods[SSL_ENC_RC2_IDX ] == NULL) ? SSL_RC2 :0;
332 	mask |= (ssl_cipher_methods[SSL_ENC_IDEA_IDX] == NULL) ? SSL_IDEA:0;
333 	mask |= (ssl_cipher_methods[SSL_ENC_eFZA_IDX] == NULL) ? SSL_eFZA:0;
334 	mask |= (ssl_cipher_methods[SSL_ENC_AES128_IDX] == NULL) ? SSL_AES:0;
335 
336 	mask |= (ssl_digest_methods[SSL_MD_MD5_IDX ] == NULL) ? SSL_MD5 :0;
337 	mask |= (ssl_digest_methods[SSL_MD_SHA1_IDX] == NULL) ? SSL_SHA1:0;
338 
339 	return(mask);
340 	}
341 
342 static void ssl_cipher_collect_ciphers(const SSL_METHOD *ssl_method,
343 		int num_of_ciphers, unsigned long mask, CIPHER_ORDER *list,
344 		CIPHER_ORDER **head_p, CIPHER_ORDER **tail_p)
345 	{
346 	int i, list_num;
347 	SSL_CIPHER *c;
348 
349 	/*
350 	 * We have num_of_ciphers descriptions compiled in, depending on the
351 	 * method selected (SSLv2 and/or SSLv3, TLSv1 etc).
352 	 * These will later be sorted in a linked list with at most num
353 	 * entries.
354 	 */
355 
356 	/* Get the initial list of ciphers */
357 	list_num = 0;	/* actual count of ciphers */
358 	for (i = 0; i < num_of_ciphers; i++)
359 		{
360 		c = ssl_method->get_cipher(i);
361 		/* drop those that use any of that is not available */
362 		if ((c != NULL) && c->valid && !(c->algorithms & mask))
363 			{
364 			list[list_num].cipher = c;
365 			list[list_num].next = NULL;
366 			list[list_num].prev = NULL;
367 			list[list_num].active = 0;
368 			list_num++;
369 #ifdef KSSL_DEBUG
370 			printf("\t%d: %s %lx %lx\n",i,c->name,c->id,c->algorithms);
371 #endif	/* KSSL_DEBUG */
372 			/*
373 			if (!sk_push(ca_list,(char *)c)) goto err;
374 			*/
375 			}
376 		}
377 
378 	/*
379 	 * Prepare linked list from list entries
380 	 */
381 	for (i = 1; i < list_num - 1; i++)
382 		{
383 		list[i].prev = &(list[i-1]);
384 		list[i].next = &(list[i+1]);
385 		}
386 	if (list_num > 0)
387 		{
388 		(*head_p) = &(list[0]);
389 		(*head_p)->prev = NULL;
390 		(*head_p)->next = &(list[1]);
391 		(*tail_p) = &(list[list_num - 1]);
392 		(*tail_p)->prev = &(list[list_num - 2]);
393 		(*tail_p)->next = NULL;
394 		}
395 	}
396 
397 static void ssl_cipher_collect_aliases(SSL_CIPHER **ca_list,
398 			int num_of_group_aliases, unsigned long mask,
399 			CIPHER_ORDER *head)
400 	{
401 	CIPHER_ORDER *ciph_curr;
402 	SSL_CIPHER **ca_curr;
403 	int i;
404 
405 	/*
406 	 * First, add the real ciphers as already collected
407 	 */
408 	ciph_curr = head;
409 	ca_curr = ca_list;
410 	while (ciph_curr != NULL)
411 		{
412 		*ca_curr = ciph_curr->cipher;
413 		ca_curr++;
414 		ciph_curr = ciph_curr->next;
415 		}
416 
417 	/*
418 	 * Now we add the available ones from the cipher_aliases[] table.
419 	 * They represent either an algorithm, that must be fully
420 	 * supported (not match any bit in mask) or represent a cipher
421 	 * strength value (will be added in any case because algorithms=0).
422 	 */
423 	for (i = 0; i < num_of_group_aliases; i++)
424 		{
425 		if ((i == 0) ||		/* always fetch "ALL" */
426 		    !(cipher_aliases[i].algorithms & mask))
427 			{
428 			*ca_curr = (SSL_CIPHER *)(cipher_aliases + i);
429 			ca_curr++;
430 			}
431 		}
432 
433 	*ca_curr = NULL;	/* end of list */
434 	}
435 
436 static void ssl_cipher_apply_rule(unsigned long algorithms, unsigned long mask,
437 		unsigned long algo_strength, unsigned long mask_strength,
438 		int rule, int strength_bits, CIPHER_ORDER *list,
439 		CIPHER_ORDER **head_p, CIPHER_ORDER **tail_p)
440 	{
441 	CIPHER_ORDER *head, *tail, *curr, *curr2, *tail2;
442 	SSL_CIPHER *cp;
443 	unsigned long ma, ma_s;
444 
445 #ifdef CIPHER_DEBUG
446 	printf("Applying rule %d with %08lx %08lx %08lx %08lx (%d)\n",
447 		rule, algorithms, mask, algo_strength, mask_strength,
448 		strength_bits);
449 #endif
450 
451 	curr = head = *head_p;
452 	curr2 = head;
453 	tail2 = tail = *tail_p;
454 	for (;;)
455 		{
456 		if ((curr == NULL) || (curr == tail2)) break;
457 		curr = curr2;
458 		curr2 = curr->next;
459 
460 		cp = curr->cipher;
461 
462 		/*
463 		 * Selection criteria is either the number of strength_bits
464 		 * or the algorithm used.
465 		 */
466 		if (strength_bits == -1)
467 			{
468 			ma = mask & cp->algorithms;
469 			ma_s = mask_strength & cp->algo_strength;
470 
471 #ifdef CIPHER_DEBUG
472 			printf("\nName: %s:\nAlgo = %08lx Algo_strength = %08lx\nMask = %08lx Mask_strength %08lx\n", cp->name, cp->algorithms, cp->algo_strength, mask, mask_strength);
473 			printf("ma = %08lx ma_s %08lx, ma&algo=%08lx, ma_s&algos=%08lx\n", ma, ma_s, ma&algorithms, ma_s&algo_strength);
474 #endif
475 			/*
476 			 * Select: if none of the mask bit was met from the
477 			 * cipher or not all of the bits were met, the
478 			 * selection does not apply.
479 			 */
480 			if (((ma == 0) && (ma_s == 0)) ||
481 			    ((ma & algorithms) != ma) ||
482 			    ((ma_s & algo_strength) != ma_s))
483 				continue; /* does not apply */
484 			}
485 		else if (strength_bits != cp->strength_bits)
486 			continue;	/* does not apply */
487 
488 #ifdef CIPHER_DEBUG
489 		printf("Action = %d\n", rule);
490 #endif
491 
492 		/* add the cipher if it has not been added yet. */
493 		if (rule == CIPHER_ADD)
494 			{
495 			if (!curr->active)
496 				{
497 				ll_append_tail(&head, curr, &tail);
498 				curr->active = 1;
499 				}
500 			}
501 		/* Move the added cipher to this location */
502 		else if (rule == CIPHER_ORD)
503 			{
504 			if (curr->active)
505 				{
506 				ll_append_tail(&head, curr, &tail);
507 				}
508 			}
509 		else if	(rule == CIPHER_DEL)
510 			curr->active = 0;
511 		else if (rule == CIPHER_KILL)
512 			{
513 			if (head == curr)
514 				head = curr->next;
515 			else
516 				curr->prev->next = curr->next;
517 			if (tail == curr)
518 				tail = curr->prev;
519 			curr->active = 0;
520 			if (curr->next != NULL)
521 				curr->next->prev = curr->prev;
522 			if (curr->prev != NULL)
523 				curr->prev->next = curr->next;
524 			curr->next = NULL;
525 			curr->prev = NULL;
526 			}
527 		}
528 
529 	*head_p = head;
530 	*tail_p = tail;
531 	}
532 
533 static int ssl_cipher_strength_sort(CIPHER_ORDER *list, CIPHER_ORDER **head_p,
534 				     CIPHER_ORDER **tail_p)
535 	{
536 	int max_strength_bits, i, *number_uses;
537 	CIPHER_ORDER *curr;
538 
539 	/*
540 	 * This routine sorts the ciphers with descending strength. The sorting
541 	 * must keep the pre-sorted sequence, so we apply the normal sorting
542 	 * routine as '+' movement to the end of the list.
543 	 */
544 	max_strength_bits = 0;
545 	curr = *head_p;
546 	while (curr != NULL)
547 		{
548 		if (curr->active &&
549 		    (curr->cipher->strength_bits > max_strength_bits))
550 		    max_strength_bits = curr->cipher->strength_bits;
551 		curr = curr->next;
552 		}
553 
554 	number_uses = OPENSSL_malloc((max_strength_bits + 1) * sizeof(int));
555 	if (!number_uses)
556 	{
557 		SSLerr(SSL_F_SSL_CIPHER_STRENGTH_SORT,ERR_R_MALLOC_FAILURE);
558 		return(0);
559 	}
560 	memset(number_uses, 0, (max_strength_bits + 1) * sizeof(int));
561 
562 	/*
563 	 * Now find the strength_bits values actually used
564 	 */
565 	curr = *head_p;
566 	while (curr != NULL)
567 		{
568 		if (curr->active)
569 			number_uses[curr->cipher->strength_bits]++;
570 		curr = curr->next;
571 		}
572 	/*
573 	 * Go through the list of used strength_bits values in descending
574 	 * order.
575 	 */
576 	for (i = max_strength_bits; i >= 0; i--)
577 		if (number_uses[i] > 0)
578 			ssl_cipher_apply_rule(0, 0, 0, 0, CIPHER_ORD, i,
579 					list, head_p, tail_p);
580 
581 	OPENSSL_free(number_uses);
582 	return(1);
583 	}
584 
585 static int ssl_cipher_process_rulestr(const char *rule_str,
586 		CIPHER_ORDER *list, CIPHER_ORDER **head_p,
587 		CIPHER_ORDER **tail_p, SSL_CIPHER **ca_list)
588 	{
589 	unsigned long algorithms, mask, algo_strength, mask_strength;
590 	const char *l, *start, *buf;
591 	int j, multi, found, rule, retval, ok, buflen;
592 	char ch;
593 
594 	retval = 1;
595 	l = rule_str;
596 	for (;;)
597 		{
598 		ch = *l;
599 
600 		if (ch == '\0')
601 			break;		/* done */
602 		if (ch == '-')
603 			{ rule = CIPHER_DEL; l++; }
604 		else if (ch == '+')
605 			{ rule = CIPHER_ORD; l++; }
606 		else if (ch == '!')
607 			{ rule = CIPHER_KILL; l++; }
608 		else if (ch == '@')
609 			{ rule = CIPHER_SPECIAL; l++; }
610 		else
611 			{ rule = CIPHER_ADD; }
612 
613 		if (ITEM_SEP(ch))
614 			{
615 			l++;
616 			continue;
617 			}
618 
619 		algorithms = mask = algo_strength = mask_strength = 0;
620 
621 		start=l;
622 		for (;;)
623 			{
624 			ch = *l;
625 			buf = l;
626 			buflen = 0;
627 #ifndef CHARSET_EBCDIC
628 			while (	((ch >= 'A') && (ch <= 'Z')) ||
629 				((ch >= '0') && (ch <= '9')) ||
630 				((ch >= 'a') && (ch <= 'z')) ||
631 				 (ch == '-'))
632 #else
633 			while (	isalnum(ch) || (ch == '-'))
634 #endif
635 				 {
636 				 ch = *(++l);
637 				 buflen++;
638 				 }
639 
640 			if (buflen == 0)
641 				{
642 				/*
643 				 * We hit something we cannot deal with,
644 				 * it is no command or separator nor
645 				 * alphanumeric, so we call this an error.
646 				 */
647 				SSLerr(SSL_F_SSL_CIPHER_PROCESS_RULESTR,
648 				       SSL_R_INVALID_COMMAND);
649 				retval = found = 0;
650 				l++;
651 				break;
652 				}
653 
654 			if (rule == CIPHER_SPECIAL)
655 				{
656 				found = 0; /* unused -- avoid compiler warning */
657 				break;	/* special treatment */
658 				}
659 
660 			/* check for multi-part specification */
661 			if (ch == '+')
662 				{
663 				multi=1;
664 				l++;
665 				}
666 			else
667 				multi=0;
668 
669 			/*
670 			 * Now search for the cipher alias in the ca_list. Be careful
671 			 * with the strncmp, because the "buflen" limitation
672 			 * will make the rule "ADH:SOME" and the cipher
673 			 * "ADH-MY-CIPHER" look like a match for buflen=3.
674 			 * So additionally check whether the cipher name found
675 			 * has the correct length. We can save a strlen() call:
676 			 * just checking for the '\0' at the right place is
677 			 * sufficient, we have to strncmp() anyway. (We cannot
678 			 * use strcmp(), because buf is not '\0' terminated.)
679 			 */
680 			 j = found = 0;
681 			 while (ca_list[j])
682 				{
683 				if (!strncmp(buf, ca_list[j]->name, buflen) &&
684 				    (ca_list[j]->name[buflen] == '\0'))
685 					{
686 					found = 1;
687 					break;
688 					}
689 				else
690 					j++;
691 				}
692 			if (!found)
693 				break;	/* ignore this entry */
694 
695 			algorithms |= ca_list[j]->algorithms;
696 			mask |= ca_list[j]->mask;
697 			algo_strength |= ca_list[j]->algo_strength;
698 			mask_strength |= ca_list[j]->mask_strength;
699 
700 			if (!multi) break;
701 			}
702 
703 		/*
704 		 * Ok, we have the rule, now apply it
705 		 */
706 		if (rule == CIPHER_SPECIAL)
707 			{	/* special command */
708 			ok = 0;
709 			if ((buflen == 8) &&
710 				!strncmp(buf, "STRENGTH", 8))
711 				ok = ssl_cipher_strength_sort(list,
712 					head_p, tail_p);
713 			else
714 				SSLerr(SSL_F_SSL_CIPHER_PROCESS_RULESTR,
715 					SSL_R_INVALID_COMMAND);
716 			if (ok == 0)
717 				retval = 0;
718 			/*
719 			 * We do not support any "multi" options
720 			 * together with "@", so throw away the
721 			 * rest of the command, if any left, until
722 			 * end or ':' is found.
723 			 */
724 			while ((*l != '\0') && ITEM_SEP(*l))
725 				l++;
726 			}
727 		else if (found)
728 			{
729 			ssl_cipher_apply_rule(algorithms, mask,
730 				algo_strength, mask_strength, rule, -1,
731 				list, head_p, tail_p);
732 			}
733 		else
734 			{
735 			while ((*l != '\0') && ITEM_SEP(*l))
736 				l++;
737 			}
738 		if (*l == '\0') break; /* done */
739 		}
740 
741 	return(retval);
742 	}
743 
744 STACK_OF(SSL_CIPHER) *ssl_create_cipher_list(const SSL_METHOD *ssl_method,
745 		STACK_OF(SSL_CIPHER) **cipher_list,
746 		STACK_OF(SSL_CIPHER) **cipher_list_by_id,
747 		const char *rule_str)
748 	{
749 	int ok, num_of_ciphers, num_of_alias_max, num_of_group_aliases;
750 	unsigned long disabled_mask;
751 	STACK_OF(SSL_CIPHER) *cipherstack;
752 	const char *rule_p;
753 	CIPHER_ORDER *list = NULL, *head = NULL, *tail = NULL, *curr;
754 	SSL_CIPHER **ca_list = NULL;
755 
756 	/*
757 	 * Return with error if nothing to do.
758 	 */
759 	if (rule_str == NULL) return(NULL);
760 
761 	if (init_ciphers)
762 		{
763 		CRYPTO_w_lock(CRYPTO_LOCK_SSL);
764 		if (init_ciphers) load_ciphers();
765 		CRYPTO_w_unlock(CRYPTO_LOCK_SSL);
766 		}
767 
768 	/*
769 	 * To reduce the work to do we only want to process the compiled
770 	 * in algorithms, so we first get the mask of disabled ciphers.
771 	 */
772 	disabled_mask = ssl_cipher_get_disabled();
773 
774 	/*
775 	 * Now we have to collect the available ciphers from the compiled
776 	 * in ciphers. We cannot get more than the number compiled in, so
777 	 * it is used for allocation.
778 	 */
779 	num_of_ciphers = ssl_method->num_ciphers();
780 #ifdef KSSL_DEBUG
781 	printf("ssl_create_cipher_list() for %d ciphers\n", num_of_ciphers);
782 #endif    /* KSSL_DEBUG */
783 	list = (CIPHER_ORDER *)OPENSSL_malloc(sizeof(CIPHER_ORDER) * num_of_ciphers);
784 	if (list == NULL)
785 		{
786 		SSLerr(SSL_F_SSL_CREATE_CIPHER_LIST,ERR_R_MALLOC_FAILURE);
787 		return(NULL);	/* Failure */
788 		}
789 
790 	ssl_cipher_collect_ciphers(ssl_method, num_of_ciphers, disabled_mask,
791 				   list, &head, &tail);
792 
793 	/*
794 	 * We also need cipher aliases for selecting based on the rule_str.
795 	 * There might be two types of entries in the rule_str: 1) names
796 	 * of ciphers themselves 2) aliases for groups of ciphers.
797 	 * For 1) we need the available ciphers and for 2) the cipher
798 	 * groups of cipher_aliases added together in one list (otherwise
799 	 * we would be happy with just the cipher_aliases table).
800 	 */
801 	num_of_group_aliases = sizeof(cipher_aliases) / sizeof(SSL_CIPHER);
802 	num_of_alias_max = num_of_ciphers + num_of_group_aliases + 1;
803 	ca_list =
804 		(SSL_CIPHER **)OPENSSL_malloc(sizeof(SSL_CIPHER *) * num_of_alias_max);
805 	if (ca_list == NULL)
806 		{
807 		OPENSSL_free(list);
808 		SSLerr(SSL_F_SSL_CREATE_CIPHER_LIST,ERR_R_MALLOC_FAILURE);
809 		return(NULL);	/* Failure */
810 		}
811 	ssl_cipher_collect_aliases(ca_list, num_of_group_aliases, disabled_mask,
812 				   head);
813 
814 	/*
815 	 * If the rule_string begins with DEFAULT, apply the default rule
816 	 * before using the (possibly available) additional rules.
817 	 */
818 	ok = 1;
819 	rule_p = rule_str;
820 	if (strncmp(rule_str,"DEFAULT",7) == 0)
821 		{
822 		ok = ssl_cipher_process_rulestr(SSL_DEFAULT_CIPHER_LIST,
823 			list, &head, &tail, ca_list);
824 		rule_p += 7;
825 		if (*rule_p == ':')
826 			rule_p++;
827 		}
828 
829 	if (ok && (strlen(rule_p) > 0))
830 		ok = ssl_cipher_process_rulestr(rule_p, list, &head, &tail,
831 						ca_list);
832 
833 	OPENSSL_free(ca_list);	/* Not needed anymore */
834 
835 	if (!ok)
836 		{	/* Rule processing failure */
837 		OPENSSL_free(list);
838 		return(NULL);
839 		}
840 	/*
841 	 * Allocate new "cipherstack" for the result, return with error
842 	 * if we cannot get one.
843 	 */
844 	if ((cipherstack = sk_SSL_CIPHER_new_null()) == NULL)
845 		{
846 		OPENSSL_free(list);
847 		return(NULL);
848 		}
849 
850 	/*
851 	 * The cipher selection for the list is done. The ciphers are added
852 	 * to the resulting precedence to the STACK_OF(SSL_CIPHER).
853 	 */
854 	for (curr = head; curr != NULL; curr = curr->next)
855 		{
856 		if (curr->active)
857 			{
858 			sk_SSL_CIPHER_push(cipherstack, curr->cipher);
859 #ifdef CIPHER_DEBUG
860 			printf("<%s>\n",curr->cipher->name);
861 #endif
862 			}
863 		}
864 	OPENSSL_free(list);	/* Not needed any longer */
865 
866 	/*
867 	 * The following passage is a little bit odd. If pointer variables
868 	 * were supplied to hold STACK_OF(SSL_CIPHER) return information,
869 	 * the old memory pointed to is free()ed. Then, however, the
870 	 * cipher_list entry will be assigned just a copy of the returned
871 	 * cipher stack. For cipher_list_by_id a copy of the cipher stack
872 	 * will be created. See next comment...
873 	 */
874 	if (cipher_list != NULL)
875 		{
876 		if (*cipher_list != NULL)
877 			sk_SSL_CIPHER_free(*cipher_list);
878 		*cipher_list = cipherstack;
879 		}
880 
881 	if (cipher_list_by_id != NULL)
882 		{
883 		if (*cipher_list_by_id != NULL)
884 			sk_SSL_CIPHER_free(*cipher_list_by_id);
885 		*cipher_list_by_id = sk_SSL_CIPHER_dup(cipherstack);
886 		}
887 
888 	/*
889 	 * Now it is getting really strange. If something failed during
890 	 * the previous pointer assignment or if one of the pointers was
891 	 * not requested, the error condition is met. That might be
892 	 * discussable. The strange thing is however that in this case
893 	 * the memory "ret" pointed to is "free()ed" and hence the pointer
894 	 * cipher_list becomes wild. The memory reserved for
895 	 * cipher_list_by_id however is not "free()ed" and stays intact.
896 	 */
897 	if (	(cipher_list_by_id == NULL) ||
898 		(*cipher_list_by_id == NULL) ||
899 		(cipher_list == NULL) ||
900 		(*cipher_list == NULL))
901 		{
902 		sk_SSL_CIPHER_free(cipherstack);
903 		return(NULL);
904 		}
905 
906 	sk_SSL_CIPHER_set_cmp_func(*cipher_list_by_id,ssl_cipher_ptr_id_cmp);
907 
908 	return(cipherstack);
909 	}
910 
911 char *SSL_CIPHER_description(SSL_CIPHER *cipher, char *buf, int len)
912 	{
913 	int is_export,pkl,kl;
914 	char *ver,*exp;
915 	char *kx,*au,*enc,*mac;
916 	unsigned long alg,alg2,alg_s;
917 #ifdef KSSL_DEBUG
918 	static char *format="%-23s %s Kx=%-8s Au=%-4s Enc=%-9s Mac=%-4s%s AL=%lx\n";
919 #else
920 	static char *format="%-23s %s Kx=%-8s Au=%-4s Enc=%-9s Mac=%-4s%s\n";
921 #endif /* KSSL_DEBUG */
922 
923 	alg=cipher->algorithms;
924 	alg_s=cipher->algo_strength;
925 	alg2=cipher->algorithm2;
926 
927 	is_export=SSL_C_IS_EXPORT(cipher);
928 	pkl=SSL_C_EXPORT_PKEYLENGTH(cipher);
929 	kl=SSL_C_EXPORT_KEYLENGTH(cipher);
930 	exp=is_export?" export":"";
931 
932 	if (alg & SSL_SSLV2)
933 		ver="SSLv2";
934 	else if (alg & SSL_SSLV3)
935 		ver="SSLv3";
936 	else
937 		ver="unknown";
938 
939 	switch (alg&SSL_MKEY_MASK)
940 		{
941 	case SSL_kRSA:
942 		kx=is_export?(pkl == 512 ? "RSA(512)" : "RSA(1024)"):"RSA";
943 		break;
944 	case SSL_kDHr:
945 		kx="DH/RSA";
946 		break;
947 	case SSL_kDHd:
948 		kx="DH/DSS";
949 		break;
950         case SSL_kKRB5:         /* VRS */
951         case SSL_KRB5:          /* VRS */
952             kx="KRB5";
953             break;
954 	case SSL_kFZA:
955 		kx="Fortezza";
956 		break;
957 	case SSL_kEDH:
958 		kx=is_export?(pkl == 512 ? "DH(512)" : "DH(1024)"):"DH";
959 		break;
960 	default:
961 		kx="unknown";
962 		}
963 
964 	switch (alg&SSL_AUTH_MASK)
965 		{
966 	case SSL_aRSA:
967 		au="RSA";
968 		break;
969 	case SSL_aDSS:
970 		au="DSS";
971 		break;
972 	case SSL_aDH:
973 		au="DH";
974 		break;
975         case SSL_aKRB5:         /* VRS */
976         case SSL_KRB5:          /* VRS */
977             au="KRB5";
978             break;
979 	case SSL_aFZA:
980 	case SSL_aNULL:
981 		au="None";
982 		break;
983 	default:
984 		au="unknown";
985 		break;
986 		}
987 
988 	switch (alg&SSL_ENC_MASK)
989 		{
990 	case SSL_DES:
991 		enc=(is_export && kl == 5)?"DES(40)":"DES(56)";
992 		break;
993 	case SSL_3DES:
994 		enc="3DES(168)";
995 		break;
996 	case SSL_RC4:
997 		enc=is_export?(kl == 5 ? "RC4(40)" : "RC4(56)")
998 		  :((alg2&SSL2_CF_8_BYTE_ENC)?"RC4(64)":"RC4(128)");
999 		break;
1000 	case SSL_RC2:
1001 		enc=is_export?(kl == 5 ? "RC2(40)" : "RC2(56)"):"RC2(128)";
1002 		break;
1003 	case SSL_IDEA:
1004 		enc="IDEA(128)";
1005 		break;
1006 	case SSL_eFZA:
1007 		enc="Fortezza";
1008 		break;
1009 	case SSL_eNULL:
1010 		enc="None";
1011 		break;
1012 	case SSL_AES:
1013 		switch(cipher->strength_bits)
1014 			{
1015 		case 128: enc="AES(128)"; break;
1016 		case 192: enc="AES(192)"; break;
1017 		case 256: enc="AES(256)"; break;
1018 		default: enc="AES(?""?""?)"; break;
1019 			}
1020 		break;
1021 	default:
1022 		enc="unknown";
1023 		break;
1024 		}
1025 
1026 	switch (alg&SSL_MAC_MASK)
1027 		{
1028 	case SSL_MD5:
1029 		mac="MD5";
1030 		break;
1031 	case SSL_SHA1:
1032 		mac="SHA1";
1033 		break;
1034 	default:
1035 		mac="unknown";
1036 		break;
1037 		}
1038 
1039 	if (buf == NULL)
1040 		{
1041 		len=128;
1042 		buf=OPENSSL_malloc(len);
1043 		if (buf == NULL) return("OPENSSL_malloc Error");
1044 		}
1045 	else if (len < 128)
1046 		return("Buffer too small");
1047 
1048 #ifdef KSSL_DEBUG
1049 	BIO_snprintf(buf,len,format,cipher->name,ver,kx,au,enc,mac,exp,alg);
1050 #else
1051 	BIO_snprintf(buf,len,format,cipher->name,ver,kx,au,enc,mac,exp);
1052 #endif /* KSSL_DEBUG */
1053 	return(buf);
1054 	}
1055 
1056 char *SSL_CIPHER_get_version(SSL_CIPHER *c)
1057 	{
1058 	int i;
1059 
1060 	if (c == NULL) return("(NONE)");
1061 	i=(int)(c->id>>24L);
1062 	if (i == 3)
1063 		return("TLSv1/SSLv3");
1064 	else if (i == 2)
1065 		return("SSLv2");
1066 	else
1067 		return("unknown");
1068 	}
1069 
1070 /* return the actual cipher being used */
1071 const char *SSL_CIPHER_get_name(SSL_CIPHER *c)
1072 	{
1073 	if (c != NULL)
1074 		return(c->name);
1075 	return("(NONE)");
1076 	}
1077 
1078 /* number of bits for symmetric cipher */
1079 int SSL_CIPHER_get_bits(SSL_CIPHER *c, int *alg_bits)
1080 	{
1081 	int ret=0;
1082 
1083 	if (c != NULL)
1084 		{
1085 		if (alg_bits != NULL) *alg_bits = c->alg_bits;
1086 		ret = c->strength_bits;
1087 		}
1088 	return(ret);
1089 	}
1090 
1091 SSL_COMP *ssl3_comp_find(STACK_OF(SSL_COMP) *sk, int n)
1092 	{
1093 	SSL_COMP *ctmp;
1094 	int i,nn;
1095 
1096 	if ((n == 0) || (sk == NULL)) return(NULL);
1097 	nn=sk_SSL_COMP_num(sk);
1098 	for (i=0; i<nn; i++)
1099 		{
1100 		ctmp=sk_SSL_COMP_value(sk,i);
1101 		if (ctmp->id == n)
1102 			return(ctmp);
1103 		}
1104 	return(NULL);
1105 	}
1106 
1107 static int sk_comp_cmp(const SSL_COMP * const *a,
1108 			const SSL_COMP * const *b)
1109 	{
1110 	return((*a)->id-(*b)->id);
1111 	}
1112 
1113 STACK_OF(SSL_COMP) *SSL_COMP_get_compression_methods(void)
1114 	{
1115 	return(ssl_comp_methods);
1116 	}
1117 
1118 int SSL_COMP_add_compression_method(int id, COMP_METHOD *cm)
1119 	{
1120 	SSL_COMP *comp;
1121 	STACK_OF(SSL_COMP) *sk;
1122 
1123         if (cm == NULL || cm->type == NID_undef)
1124                 return 1;
1125 
1126 	MemCheck_off();
1127 	comp=(SSL_COMP *)OPENSSL_malloc(sizeof(SSL_COMP));
1128 	comp->id=id;
1129 	comp->method=cm;
1130 	if (ssl_comp_methods == NULL)
1131 		sk=ssl_comp_methods=sk_SSL_COMP_new(sk_comp_cmp);
1132 	else
1133 		sk=ssl_comp_methods;
1134 	if ((sk == NULL) || !sk_SSL_COMP_push(sk,comp))
1135 		{
1136 		MemCheck_on();
1137 		SSLerr(SSL_F_SSL_COMP_ADD_COMPRESSION_METHOD,ERR_R_MALLOC_FAILURE);
1138 		return(0);
1139 		}
1140 	else
1141 		{
1142 		MemCheck_on();
1143 		return(1);
1144 		}
1145 	}
1146