ssl/ssl_ciph.c

   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  * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
  60  * ECC cipher suite support in OpenSSL originally developed by
  61  * SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project.
  62  */
  63 #include <stdio.h>
  64 #include <openssl/objects.h>
  65 #include <openssl/comp.h>
  66 #include "ssl_locl.h"
  67
  68 #define SSL_ENC_DES_IDX         0
  69 #define SSL_ENC_3DES_IDX        1
  70 #define SSL_ENC_RC4_IDX         2
  71 #define SSL_ENC_RC2_IDX         3
  72 #define SSL_ENC_IDEA_IDX        4
  73 #define SSL_ENC_eFZA_IDX        5
  74 #define SSL_ENC_NULL_IDX        6
  75 #define SSL_ENC_AES128_IDX      7
  76 #define SSL_ENC_AES256_IDX      8
  77 #define SSL_ENC_NUM_IDX         9
  78
  79 static const EVP_CIPHER *ssl_cipher_methods[SSL_ENC_NUM_IDX]={
  80         NULL,NULL,NULL,NULL,NULL,NULL,
  81         };
  82
  83 #define SSL_COMP_NULL_IDX       0
  84 #define SSL_COMP_ZLIB_IDX       1
  85 #define SSL_COMP_NUM_IDX        2
  86
  87 static STACK_OF(SSL_COMP) *ssl_comp_methods=NULL;
  88
  89 #define SSL_MD_MD5_IDX  0
  90 #define SSL_MD_SHA1_IDX 1
  91 #define SSL_MD_NUM_IDX  2
  92 static const EVP_MD *ssl_digest_methods[SSL_MD_NUM_IDX]={
  93         NULL,NULL,
  94         };
  95
  96 #define CIPHER_ADD      1
  97 #define CIPHER_KILL     2
  98 #define CIPHER_DEL      3
  99 #define CIPHER_ORD      4
 100 #define CIPHER_SPECIAL  5
 101
 102 typedef struct cipher_order_st
 103         {
 104         SSL_CIPHER *cipher;
 105         int active;
 106         int dead;
 107         struct cipher_order_st *next,*prev;
 108         } CIPHER_ORDER;
 109
 110 static const SSL_CIPHER cipher_aliases[]={
 111         /* Don't include eNULL unless specifically enabled. */
 112         /* Don't include ECC in ALL because these ciphers are not yet official. */
 113         {0,SSL_TXT_ALL, 0,SSL_ALL & ~SSL_eNULL & ~SSL_kECDH & ~SSL_kECDHE, SSL_ALL ,0,0,0,SSL_ALL,SSL_ALL}, /* must be first */
 114         /* TODO: COMPLEMENT OF ALL and COMPLEMENT OF DEFAULT do not have ECC cipher suites handled properly. */
 115         {0,SSL_TXT_CMPALL,0,SSL_eNULL,0,0,0,0,SSL_ENC_MASK,0},  /* COMPLEMENT OF ALL */
 116         {0,SSL_TXT_CMPDEF,0,SSL_ADH, 0,0,0,0,SSL_AUTH_MASK,0},
 117         {0,SSL_TXT_kKRB5,0,SSL_kKRB5,0,0,0,0,SSL_MKEY_MASK,0},  /* VRS Kerberos5 */
 118         {0,SSL_TXT_kRSA,0,SSL_kRSA,  0,0,0,0,SSL_MKEY_MASK,0},
 119         {0,SSL_TXT_kDHr,0,SSL_kDHr,  0,0,0,0,SSL_MKEY_MASK,0},
 120         {0,SSL_TXT_kDHd,0,SSL_kDHd,  0,0,0,0,SSL_MKEY_MASK,0},
 121         {0,SSL_TXT_kEDH,0,SSL_kEDH,  0,0,0,0,SSL_MKEY_MASK,0},
 122         {0,SSL_TXT_kFZA,0,SSL_kFZA,  0,0,0,0,SSL_MKEY_MASK,0},
 123         {0,SSL_TXT_DH,  0,SSL_DH,    0,0,0,0,SSL_MKEY_MASK,0},
 124         {0,SSL_TXT_ECC, 0,(SSL_kECDH|SSL_kECDHE), 0,0,0,0,SSL_MKEY_MASK,0},
 125         {0,SSL_TXT_EDH, 0,SSL_EDH,   0,0,0,0,SSL_MKEY_MASK|SSL_AUTH_MASK,0},
 126         {0,SSL_TXT_aKRB5,0,SSL_aKRB5,0,0,0,0,SSL_AUTH_MASK,0},  /* VRS Kerberos5 */
 127         {0,SSL_TXT_aRSA,0,SSL_aRSA,  0,0,0,0,SSL_AUTH_MASK,0},
 128         {0,SSL_TXT_aDSS,0,SSL_aDSS,  0,0,0,0,SSL_AUTH_MASK,0},
 129         {0,SSL_TXT_aFZA,0,SSL_aFZA,  0,0,0,0,SSL_AUTH_MASK,0},
 130         {0,SSL_TXT_aNULL,0,SSL_aNULL,0,0,0,0,SSL_AUTH_MASK,0},
 131         {0,SSL_TXT_aDH, 0,SSL_aDH,   0,0,0,0,SSL_AUTH_MASK,0},
 132         {0,SSL_TXT_DSS, 0,SSL_DSS,   0,0,0,0,SSL_AUTH_MASK,0},
 133
 134         {0,SSL_TXT_DES, 0,SSL_DES,   0,0,0,0,SSL_ENC_MASK,0},
 135         {0,SSL_TXT_3DES,0,SSL_3DES,  0,0,0,0,SSL_ENC_MASK,0},
 136         {0,SSL_TXT_RC4, 0,SSL_RC4,   0,0,0,0,SSL_ENC_MASK,0},
 137         {0,SSL_TXT_RC2, 0,SSL_RC2,   0,0,0,0,SSL_ENC_MASK,0},
 138 #ifndef OPENSSL_NO_IDEA
 139         {0,SSL_TXT_IDEA,0,SSL_IDEA,  0,0,0,0,SSL_ENC_MASK,0},
 140 #endif
 141         {0,SSL_TXT_eNULL,0,SSL_eNULL,0,0,0,0,SSL_ENC_MASK,0},
 142         {0,SSL_TXT_eFZA,0,SSL_eFZA,  0,0,0,0,SSL_ENC_MASK,0},
 143         {0,SSL_TXT_AES, 0,SSL_AES,   0,0,0,0,SSL_ENC_MASK,0},
 144
 145         {0,SSL_TXT_MD5, 0,SSL_MD5,   0,0,0,0,SSL_MAC_MASK,0},
 146         {0,SSL_TXT_SHA1,0,SSL_SHA1,  0,0,0,0,SSL_MAC_MASK,0},
 147         {0,SSL_TXT_SHA, 0,SSL_SHA,   0,0,0,0,SSL_MAC_MASK,0},
 148
 149         {0,SSL_TXT_NULL,0,SSL_NULL,  0,0,0,0,SSL_ENC_MASK,0},
 150         {0,SSL_TXT_KRB5,0,SSL_KRB5,  0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK,0},
 151         {0,SSL_TXT_RSA, 0,SSL_RSA,   0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK,0},
 152         {0,SSL_TXT_ADH, 0,SSL_ADH,   0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK,0},
 153         {0,SSL_TXT_FZA, 0,SSL_FZA,   0,0,0,0,SSL_AUTH_MASK|SSL_MKEY_MASK|SSL_ENC_MASK,0},
 154
 155         {0,SSL_TXT_SSLV2, 0,SSL_SSLV2, 0,0,0,0,SSL_SSL_MASK,0},
 156         {0,SSL_TXT_SSLV3, 0,SSL_SSLV3, 0,0,0,0,SSL_SSL_MASK,0},
 157         {0,SSL_TXT_TLSV1, 0,SSL_TLSV1, 0,0,0,0,SSL_SSL_MASK,0},
 158
 159         {0,SSL_TXT_EXP   ,0, 0,SSL_EXPORT, 0,0,0,0,SSL_EXP_MASK},
 160         {0,SSL_TXT_EXPORT,0, 0,SSL_EXPORT, 0,0,0,0,SSL_EXP_MASK},
 161         {0,SSL_TXT_EXP40, 0, 0, SSL_EXP40, 0,0,0,0,SSL_STRONG_MASK},
 162         {0,SSL_TXT_EXP56, 0, 0, SSL_EXP56, 0,0,0,0,SSL_STRONG_MASK},
 163         {0,SSL_TXT_LOW,   0, 0,   SSL_LOW, 0,0,0,0,SSL_STRONG_MASK},
 164         {0,SSL_TXT_MEDIUM,0, 0,SSL_MEDIUM, 0,0,0,0,SSL_STRONG_MASK},
 165         {0,SSL_TXT_HIGH,  0, 0,  SSL_HIGH, 0,0,0,0,SSL_STRONG_MASK},
 166         };
 167
 168 void ssl_load_ciphers(void)
 169         {
 170         ssl_cipher_methods[SSL_ENC_DES_IDX]=
 171                 EVP_get_cipherbyname(SN_des_cbc);
 172         ssl_cipher_methods[SSL_ENC_3DES_IDX]=
 173                 EVP_get_cipherbyname(SN_des_ede3_cbc);
 174         ssl_cipher_methods[SSL_ENC_RC4_IDX]=
 175                 EVP_get_cipherbyname(SN_rc4);
 176         ssl_cipher_methods[SSL_ENC_RC2_IDX]=
 177                 EVP_get_cipherbyname(SN_rc2_cbc);
 178 #ifndef OPENSSL_NO_IDEA
 179         ssl_cipher_methods[SSL_ENC_IDEA_IDX]=
 180                 EVP_get_cipherbyname(SN_idea_cbc);
 181 #else
 182         ssl_cipher_methods[SSL_ENC_IDEA_IDX]= NULL;
 183 #endif
 184         ssl_cipher_methods[SSL_ENC_AES128_IDX]=
 185           EVP_get_cipherbyname(SN_aes_128_cbc);
 186         ssl_cipher_methods[SSL_ENC_AES256_IDX]=
 187           EVP_get_cipherbyname(SN_aes_256_cbc);
 188
 189         ssl_digest_methods[SSL_MD_MD5_IDX]=
 190                 EVP_get_digestbyname(SN_md5);
 191         ssl_digest_methods[SSL_MD_SHA1_IDX]=
 192                 EVP_get_digestbyname(SN_sha1);
 193         }
 194
 195 static int sk_comp_cmp(const SSL_COMP * const *a,
 196                         const SSL_COMP * const *b)
 197         {
 198         return((*a)->id-(*b)->id);
 199         }
 200
 201 static void load_builtin_compressions(void)
 202         {
 203         if (ssl_comp_methods != NULL)
 204                 return;
 205
 206         CRYPTO_w_lock(CRYPTO_LOCK_SSL);
 207         if (ssl_comp_methods == NULL)
 208                 {
 209                 SSL_COMP *comp = NULL;
 210
 211                 MemCheck_off();
 212                 ssl_comp_methods=sk_SSL_COMP_new(sk_comp_cmp);
 213                 if (ssl_comp_methods != NULL)
 214                         {
 215                         comp=(SSL_COMP *)OPENSSL_malloc(sizeof(SSL_COMP));
 216                         if (comp != NULL)
 217                                 {
 218                                 comp->method=COMP_zlib();
 219                                 if (comp->method
 220                                         && comp->method->type == NID_undef)
 221                                         OPENSSL_free(comp);
 222                                 else
 223                                         {
 224                                         comp->id=SSL_COMP_ZLIB_IDX;
 225                                         comp->name=comp->method->name;
 226                                         sk_SSL_COMP_push(ssl_comp_methods,comp);
 227                                         }
 228                                 }
 229                         }
 230                 MemCheck_on();
 231                 }
 232         CRYPTO_w_unlock(CRYPTO_LOCK_SSL);
 233         }
 234
 235 int ssl_cipher_get_evp(const SSL_SESSION *s, const EVP_CIPHER **enc,
 236              const EVP_MD **md, SSL_COMP **comp)
 237         {
 238         int i;
 239         SSL_CIPHER *c;
 240
 241         c=s->cipher;
 242         if (c == NULL) return(0);
 243         if (comp != NULL)
 244                 {
 245                 SSL_COMP ctmp;
 246
 247                 load_builtin_compressions();
 248
 249                 *comp=NULL;
 250                 ctmp.id=s->compress_meth;
 251                 if (ssl_comp_methods != NULL)
 252                         {
 253                         i=sk_SSL_COMP_find(ssl_comp_methods,&ctmp);
 254                         if (i >= 0)
 255                                 *comp=sk_SSL_COMP_value(ssl_comp_methods,i);
 256                         else
 257                                 *comp=NULL;
 258                         }
 259                 }
 260
 261         if ((enc == NULL) || (md == NULL)) return(0);
 262
 263         switch (c->algorithms & SSL_ENC_MASK)
 264                 {
 265         case SSL_DES:
 266                 i=SSL_ENC_DES_IDX;
 267                 break;
 268         case SSL_3DES:
 269                 i=SSL_ENC_3DES_IDX;
 270                 break;
 271         case SSL_RC4:
 272                 i=SSL_ENC_RC4_IDX;
 273                 break;
 274         case SSL_RC2:
 275                 i=SSL_ENC_RC2_IDX;
 276                 break;
 277         case SSL_IDEA:
 278                 i=SSL_ENC_IDEA_IDX;
 279                 break;
 280         case SSL_eNULL:
 281                 i=SSL_ENC_NULL_IDX;
 282                 break;
 283         case SSL_AES:
 284                 switch(c->alg_bits)
 285                         {
 286                 case 128: i=SSL_ENC_AES128_IDX; break;
 287                 case 256: i=SSL_ENC_AES256_IDX; break;
 288                 default: i=-1; break;
 289                         }
 290                 break;
 291         default:
 292                 i= -1;
 293                 break;
 294                 }
 295
 296         if ((i < 0) || (i > SSL_ENC_NUM_IDX))
 297                 *enc=NULL;
 298         else
 299                 {
 300                 if (i == SSL_ENC_NULL_IDX)
 301                         *enc=EVP_enc_null();
 302                 else
 303                         *enc=ssl_cipher_methods[i];
 304                 }
 305
 306         switch (c->algorithms & SSL_MAC_MASK)
 307                 {
 308         case SSL_MD5:
 309                 i=SSL_MD_MD5_IDX;
 310                 break;
 311         case SSL_SHA1:
 312                 i=SSL_MD_SHA1_IDX;
 313                 break;
 314         default:
 315                 i= -1;
 316                 break;
 317                 }
 318         if ((i < 0) || (i > SSL_MD_NUM_IDX))
 319                 *md=NULL;
 320         else
 321                 *md=ssl_digest_methods[i];
 322
 323         if ((*enc != NULL) && (*md != NULL))
 324                 return(1);
 325         else
 326                 return(0);
 327         }
 328
 329 #define ITEM_SEP(a) \
 330         (((a) == ':') || ((a) == ' ') || ((a) == ';') || ((a) == ','))
 331
 332 static void ll_append_tail(CIPHER_ORDER **head, CIPHER_ORDER *curr,
 333              CIPHER_ORDER **tail)
 334         {
 335         if (curr == *tail) return;
 336         if (curr == *head)
 337                 *head=curr->next;
 338         if (curr->prev != NULL)
 339                 curr->prev->next=curr->next;
 340         if (curr->next != NULL) /* should always be true */
 341                 curr->next->prev=curr->prev;
 342         (*tail)->next=curr;
 343         curr->prev= *tail;
 344         curr->next=NULL;
 345         *tail=curr;
 346         }
 347
 348 static unsigned long ssl_cipher_get_disabled(void)
 349         {
 350         unsigned long mask;
 351
 352         mask = SSL_kFZA;
 353 #ifdef OPENSSL_NO_RSA
 354         mask |= SSL_aRSA|SSL_kRSA;
 355 #endif
 356 #ifdef OPENSSL_NO_DSA
 357         mask |= SSL_aDSS;
 358 #endif
 359 #ifdef OPENSSL_NO_DH
 360         mask |= SSL_kDHr|SSL_kDHd|SSL_kEDH|SSL_aDH;
 361 #endif
 362 #ifdef OPENSSL_NO_KRB5
 363         mask |= SSL_kKRB5|SSL_aKRB5;
 364 #endif
 365 #ifdef OPENSSL_NO_ECDH
 366         mask |= SSL_kECDH|SSL_kECDHE;
 367 #endif
 368 #ifdef SSL_FORBID_ENULL
 369         mask |= SSL_eNULL;
 370 #endif
 371
 372         mask |= (ssl_cipher_methods[SSL_ENC_DES_IDX ] == NULL) ? SSL_DES :0;
 373         mask |= (ssl_cipher_methods[SSL_ENC_3DES_IDX] == NULL) ? SSL_3DES:0;
 374         mask |= (ssl_cipher_methods[SSL_ENC_RC4_IDX ] == NULL) ? SSL_RC4 :0;
 375         mask |= (ssl_cipher_methods[SSL_ENC_RC2_IDX ] == NULL) ? SSL_RC2 :0;
 376         mask |= (ssl_cipher_methods[SSL_ENC_IDEA_IDX] == NULL) ? SSL_IDEA:0;
 377         mask |= (ssl_cipher_methods[SSL_ENC_eFZA_IDX] == NULL) ? SSL_eFZA:0;
 378         mask |= (ssl_cipher_methods[SSL_ENC_AES128_IDX] == NULL) ? SSL_AES:0;
 379
 380         mask |= (ssl_digest_methods[SSL_MD_MD5_IDX ] == NULL) ? SSL_MD5 :0;
 381         mask |= (ssl_digest_methods[SSL_MD_SHA1_IDX] == NULL) ? SSL_SHA1:0;
 382
 383         return(mask);
 384         }
 385
 386 static void ssl_cipher_collect_ciphers(const SSL_METHOD *ssl_method,
 387                 int num_of_ciphers, unsigned long mask, CIPHER_ORDER *co_list,
 388                 CIPHER_ORDER **head_p, CIPHER_ORDER **tail_p)
 389         {
 390         int i, co_list_num;
 391         SSL_CIPHER *c;
 392
 393         /*
 394          * We have num_of_ciphers descriptions compiled in, depending on the
 395          * method selected (SSLv2 and/or SSLv3, TLSv1 etc).
 396          * These will later be sorted in a linked list with at most num
 397          * entries.
 398          */
 399
 400         /* Get the initial list of ciphers */
 401         co_list_num = 0;        /* actual count of ciphers */
 402         for (i = 0; i < num_of_ciphers; i++)
 403                 {
 404                 c = ssl_method->get_cipher(i);
 405                 /* drop those that use any of that is not available */
 406                 if ((c != NULL) && c->valid && !(c->algorithms & mask))
 407                         {
 408                         co_list[co_list_num].cipher = c;
 409                         co_list[co_list_num].next = NULL;
 410                         co_list[co_list_num].prev = NULL;
 411                         co_list[co_list_num].active = 0;
 412                         co_list_num++;
 413 #ifdef KSSL_DEBUG
 414                         printf("\t%d: %s %lx %lx\n",i,c->name,c->id,c->algorithms);
 415 #endif  /* KSSL_DEBUG */
 416                         /*
 417                         if (!sk_push(ca_list,(char *)c)) goto err;
 418                         */
 419                         }
 420                 }
 421
 422         /*
 423          * Prepare linked list from list entries
 424          */
 425         for (i = 1; i < co_list_num - 1; i++)
 426                 {
 427                 co_list[i].prev = &(co_list[i-1]);
 428                 co_list[i].next = &(co_list[i+1]);
 429                 }
 430         if (co_list_num > 0)
 431                 {
 432                 (*head_p) = &(co_list[0]);
 433                 (*head_p)->prev = NULL;
 434                 (*head_p)->next = &(co_list[1]);
 435                 (*tail_p) = &(co_list[co_list_num - 1]);
 436                 (*tail_p)->prev = &(co_list[co_list_num - 2]);
 437                 (*tail_p)->next = NULL;
 438                 }
 439         }
 440
 441 static void ssl_cipher_collect_aliases(SSL_CIPHER **ca_list,
 442                         int num_of_group_aliases, unsigned long mask,
 443                         CIPHER_ORDER *head)
 444         {
 445         CIPHER_ORDER *ciph_curr;
 446         SSL_CIPHER **ca_curr;
 447         int i;
 448
 449         /*
 450          * First, add the real ciphers as already collected
 451          */
 452         ciph_curr = head;
 453         ca_curr = ca_list;
 454         while (ciph_curr != NULL)
 455                 {
 456                 *ca_curr = ciph_curr->cipher;
 457                 ca_curr++;
 458                 ciph_curr = ciph_curr->next;
 459                 }
 460
 461         /*
 462          * Now we add the available ones from the cipher_aliases[] table.
 463          * They represent either an algorithm, that must be fully
 464          * supported (not match any bit in mask) or represent a cipher
 465          * strength value (will be added in any case because algorithms=0).
 466          */
 467         for (i = 0; i < num_of_group_aliases; i++)
 468                 {
 469                 if ((i == 0) ||         /* always fetch "ALL" */
 470                     !(cipher_aliases[i].algorithms & mask))
 471                         {
 472                         *ca_curr = (SSL_CIPHER *)(cipher_aliases + i);
 473                         ca_curr++;
 474                         }
 475                 }
 476
 477         *ca_curr = NULL;        /* end of list */
 478         }
 479
 480 static void ssl_cipher_apply_rule(unsigned long algorithms, unsigned long mask,
 481                 unsigned long algo_strength, unsigned long mask_strength,
 482                 int rule, int strength_bits, CIPHER_ORDER *co_list,
 483                 CIPHER_ORDER **head_p, CIPHER_ORDER **tail_p)
 484         {
 485         CIPHER_ORDER *head, *tail, *curr, *curr2, *tail2;
 486         SSL_CIPHER *cp;
 487         unsigned long ma, ma_s;
 488
 489 #ifdef CIPHER_DEBUG
 490         printf("Applying rule %d with %08lx %08lx %08lx %08lx (%d)\n",
 491                 rule, algorithms, mask, algo_strength, mask_strength,
 492                 strength_bits);
 493 #endif
 494
 495         curr = head = *head_p;
 496         curr2 = head;
 497         tail2 = tail = *tail_p;
 498         for (;;)
 499                 {
 500                 if ((curr == NULL) || (curr == tail2)) break;
 501                 curr = curr2;
 502                 curr2 = curr->next;
 503
 504                 cp = curr->cipher;
 505
 506                 /*
 507                  * Selection criteria is either the number of strength_bits
 508                  * or the algorithm used.
 509                  */
 510                 if (strength_bits == -1)
 511                         {
 512                         ma = mask & cp->algorithms;
 513                         ma_s = mask_strength & cp->algo_strength;
 514
 515 #ifdef CIPHER_DEBUG
 516                         printf("\nName: %s:\nAlgo = %08lx Algo_strength = %08lx\nMask = %08lx Mask_strength %08lx\n", cp->name, cp->algorithms, cp->algo_strength, mask, mask_strength);
 517                         printf("ma = %08lx ma_s %08lx, ma&algo=%08lx, ma_s&algos=%08lx\n", ma, ma_s, ma&algorithms, ma_s&algo_strength);
 518 #endif
 519                         /*
 520                          * Select: if none of the mask bit was met from the
 521                          * cipher or not all of the bits were met, the
 522                          * selection does not apply.
 523                          */
 524                         if (((ma == 0) && (ma_s == 0)) ||
 525                             ((ma & algorithms) != ma) ||
 526                             ((ma_s & algo_strength) != ma_s))
 527                                 continue; /* does not apply */
 528                         }
 529                 else if (strength_bits != cp->strength_bits)
 530                         continue;       /* does not apply */
 531
 532 #ifdef CIPHER_DEBUG
 533                 printf("Action = %d\n", rule);
 534 #endif
 535
 536                 /* add the cipher if it has not been added yet. */
 537                 if (rule == CIPHER_ADD)
 538                         {
 539                         if (!curr->active)
 540                                 {
 541                                 ll_append_tail(&head, curr, &tail);
 542                                 curr->active = 1;
 543                                 }
 544                         }
 545                 /* Move the added cipher to this location */
 546                 else if (rule == CIPHER_ORD)
 547                         {
 548                         if (curr->active)
 549                                 {
 550                                 ll_append_tail(&head, curr, &tail);
 551                                 }
 552                         }
 553                 else if (rule == CIPHER_DEL)
 554                         curr->active = 0;
 555                 else if (rule == CIPHER_KILL)
 556                         {
 557                         if (head == curr)
 558                                 head = curr->next;
 559                         else
 560                                 curr->prev->next = curr->next;
 561                         if (tail == curr)
 562                                 tail = curr->prev;
 563                         curr->active = 0;
 564                         if (curr->next != NULL)
 565                                 curr->next->prev = curr->prev;
 566                         if (curr->prev != NULL)
 567                                 curr->prev->next = curr->next;
 568                         curr->next = NULL;
 569                         curr->prev = NULL;
 570                         }
 571                 }
 572
 573         *head_p = head;
 574         *tail_p = tail;
 575         }
 576
 577 static int ssl_cipher_strength_sort(CIPHER_ORDER *co_list,
 578                                     CIPHER_ORDER **head_p,
 579                                     CIPHER_ORDER **tail_p)
 580         {
 581         int max_strength_bits, i, *number_uses;
 582         CIPHER_ORDER *curr;
 583
 584         /*
 585          * This routine sorts the ciphers with descending strength. The sorting
 586          * must keep the pre-sorted sequence, so we apply the normal sorting
 587          * routine as '+' movement to the end of the list.
 588          */
 589         max_strength_bits = 0;
 590         curr = *head_p;
 591         while (curr != NULL)
 592                 {
 593                 if (curr->active &&
 594                     (curr->cipher->strength_bits > max_strength_bits))
 595                     max_strength_bits = curr->cipher->strength_bits;
 596                 curr = curr->next;
 597                 }
 598
 599         number_uses = OPENSSL_malloc((max_strength_bits + 1) * sizeof(int));
 600         if (!number_uses)
 601         {
 602                 SSLerr(SSL_F_SSL_CIPHER_STRENGTH_SORT,ERR_R_MALLOC_FAILURE);
 603                 return(0);
 604         }
 605         memset(number_uses, 0, (max_strength_bits + 1) * sizeof(int));
 606
 607         /*
 608          * Now find the strength_bits values actually used
 609          */
 610         curr = *head_p;
 611         while (curr != NULL)
 612                 {
 613                 if (curr->active)
 614                         number_uses[curr->cipher->strength_bits]++;
 615                 curr = curr->next;
 616                 }
 617         /*
 618          * Go through the list of used strength_bits values in descending
 619          * order.
 620          */
 621         for (i = max_strength_bits; i >= 0; i--)
 622                 if (number_uses[i] > 0)
 623                         ssl_cipher_apply_rule(0, 0, 0, 0, CIPHER_ORD, i,
 624                                         co_list, head_p, tail_p);
 625
 626         OPENSSL_free(number_uses);
 627         return(1);
 628         }
 629
 630 static int ssl_cipher_process_rulestr(const char *rule_str,
 631                 CIPHER_ORDER *co_list, CIPHER_ORDER **head_p,
 632                 CIPHER_ORDER **tail_p, SSL_CIPHER **ca_list)
 633         {
 634         unsigned long algorithms, mask, algo_strength, mask_strength;
 635         const char *l, *start, *buf;
 636         int j, multi, found, rule, retval, ok, buflen;
 637         char ch;
 638
 639         retval = 1;
 640         l = rule_str;
 641         for (;;)
 642                 {
 643                 ch = *l;
 644
 645                 if (ch == '\0')
 646                         break;          /* done */
 647                 if (ch == '-')
 648                         { rule = CIPHER_DEL; l++; }
 649                 else if (ch == '+')
 650                         { rule = CIPHER_ORD; l++; }
 651                 else if (ch == '!')
 652                         { rule = CIPHER_KILL; l++; }
 653                 else if (ch == '@')
 654                         { rule = CIPHER_SPECIAL; l++; }
 655                 else
 656                         { rule = CIPHER_ADD; }
 657
 658                 if (ITEM_SEP(ch))
 659                         {
 660                         l++;
 661                         continue;
 662                         }
 663
 664                 algorithms = mask = algo_strength = mask_strength = 0;
 665
 666                 start=l;
 667                 for (;;)
 668                         {
 669                         ch = *l;
 670                         buf = l;
 671                         buflen = 0;
 672 #ifndef CHARSET_EBCDIC
 673                         while ( ((ch >= 'A') && (ch <= 'Z')) ||
 674                                 ((ch >= '0') && (ch <= '9')) ||
 675                                 ((ch >= 'a') && (ch <= 'z')) ||
 676                                  (ch == '-'))
 677 #else
 678                         while ( isalnum(ch) || (ch == '-'))
 679 #endif
 680                                  {
 681                                  ch = *(++l);
 682                                  buflen++;
 683                                  }
 684
 685                         if (buflen == 0)
 686                                 {
 687                                 /*
 688                                  * We hit something we cannot deal with,
 689                                  * it is no command or separator nor
 690                                  * alphanumeric, so we call this an error.
 691                                  */
 692                                 SSLerr(SSL_F_SSL_CIPHER_PROCESS_RULESTR,
 693                                        SSL_R_INVALID_COMMAND);
 694                                 retval = found = 0;
 695                                 l++;
 696                                 break;
 697                                 }
 698
 699                         if (rule == CIPHER_SPECIAL)
 700                                 {
 701                                 found = 0; /* unused -- avoid compiler warning */
 702                                 break;  /* special treatment */
 703                                 }
 704
 705                         /* check for multi-part specification */
 706                         if (ch == '+')
 707                                 {
 708                                 multi=1;
 709                                 l++;
 710                                 }
 711                         else
 712                                 multi=0;
 713
 714                         /*
 715                          * Now search for the cipher alias in the ca_list. Be careful
 716                          * with the strncmp, because the "buflen" limitation
 717                          * will make the rule "ADH:SOME" and the cipher
 718                          * "ADH-MY-CIPHER" look like a match for buflen=3.
 719                          * So additionally check whether the cipher name found
 720                          * has the correct length. We can save a strlen() call:
 721                          * just checking for the '\0' at the right place is
 722                          * sufficient, we have to strncmp() anyway. (We cannot
 723                          * use strcmp(), because buf is not '\0' terminated.)
 724                          */
 725                          j = found = 0;
 726                          while (ca_list[j])
 727                                 {
 728                                 if (!strncmp(buf, ca_list[j]->name, buflen) &&
 729                                     (ca_list[j]->name[buflen] == '\0'))
 730                                         {
 731                                         found = 1;
 732                                         break;
 733                                         }
 734                                 else
 735                                         j++;
 736                                 }
 737                         if (!found)
 738                                 break;  /* ignore this entry */
 739
 740                         /* New algorithms:
 741                          *  1 - any old restrictions apply outside new mask
 742                          *  2 - any new restrictions apply outside old mask
 743                          *  3 - enforce old & new where masks intersect
 744                          */
 745                         algorithms = (algorithms & ~ca_list[j]->mask) |         /* 1 */
 746                                      (ca_list[j]->algorithms & ~mask) |         /* 2 */
 747                                      (algorithms & ca_list[j]->algorithms);     /* 3 */
 748                         mask |= ca_list[j]->mask;
 749                         algo_strength = (algo_strength & ~ca_list[j]->mask_strength) |
 750                                         (ca_list[j]->algo_strength & ~mask_strength) |
 751                                         (algo_strength & ca_list[j]->algo_strength);
 752                         mask_strength |= ca_list[j]->mask_strength;
 753
 754                         if (!multi) break;
 755                         }
 756
 757                 /*
 758                  * Ok, we have the rule, now apply it
 759                  */
 760                 if (rule == CIPHER_SPECIAL)
 761                         {       /* special command */
 762                         ok = 0;
 763                         if ((buflen == 8) &&
 764                                 !strncmp(buf, "STRENGTH", 8))
 765                                 ok = ssl_cipher_strength_sort(co_list,
 766                                         head_p, tail_p);
 767                         else
 768                                 SSLerr(SSL_F_SSL_CIPHER_PROCESS_RULESTR,
 769                                         SSL_R_INVALID_COMMAND);
 770                         if (ok == 0)
 771                                 retval = 0;
 772                         /*
 773                          * We do not support any "multi" options
 774                          * together with "@", so throw away the
 775                          * rest of the command, if any left, until
 776                          * end or ':' is found.
 777                          */
 778                         while ((*l != '\0') && ITEM_SEP(*l))
 779                                 l++;
 780                         }
 781                 else if (found)
 782                         {
 783                         ssl_cipher_apply_rule(algorithms, mask,
 784                                 algo_strength, mask_strength, rule, -1,
 785                                 co_list, head_p, tail_p);
 786                         }
 787                 else
 788                         {
 789                         while ((*l != '\0') && ITEM_SEP(*l))
 790                                 l++;
 791                         }
 792                 if (*l == '\0') break; /* done */
 793                 }
 794
 795         return(retval);
 796         }
 797
 798 STACK_OF(SSL_CIPHER) *ssl_create_cipher_list(const SSL_METHOD *ssl_method,
 799                 STACK_OF(SSL_CIPHER) **cipher_list,
 800                 STACK_OF(SSL_CIPHER) **cipher_list_by_id,
 801                 const char *rule_str)
 802         {
 803         int ok, num_of_ciphers, num_of_alias_max, num_of_group_aliases;
 804         unsigned long disabled_mask;
 805         STACK_OF(SSL_CIPHER) *cipherstack, *tmp_cipher_list;
 806         const char *rule_p;
 807         CIPHER_ORDER *co_list = NULL, *head = NULL, *tail = NULL, *curr;
 808         SSL_CIPHER **ca_list = NULL;
 809
 810         /*
 811          * Return with error if nothing to do.
 812          */
 813         if (rule_str == NULL || cipher_list == NULL || cipher_list_by_id == NULL)
 814                 return NULL;
 815
 816         /*
 817          * To reduce the work to do we only want to process the compiled
 818          * in algorithms, so we first get the mask of disabled ciphers.
 819          */
 820         disabled_mask = ssl_cipher_get_disabled();
 821
 822         /*
 823          * Now we have to collect the available ciphers from the compiled
 824          * in ciphers. We cannot get more than the number compiled in, so
 825          * it is used for allocation.
 826          */
 827         num_of_ciphers = ssl_method->num_ciphers();
 828 #ifdef KSSL_DEBUG
 829         printf("ssl_create_cipher_list() for %d ciphers\n", num_of_ciphers);
 830 #endif    /* KSSL_DEBUG */
 831         co_list = (CIPHER_ORDER *)OPENSSL_malloc(sizeof(CIPHER_ORDER) * num_of_ciphers);
 832         if (co_list == NULL)
 833                 {
 834                 SSLerr(SSL_F_SSL_CREATE_CIPHER_LIST,ERR_R_MALLOC_FAILURE);
 835                 return(NULL);   /* Failure */
 836                 }
 837
 838         ssl_cipher_collect_ciphers(ssl_method, num_of_ciphers, disabled_mask,
 839                                    co_list, &head, &tail);
 840
 841         /*
 842          * We also need cipher aliases for selecting based on the rule_str.
 843          * There might be two types of entries in the rule_str: 1) names
 844          * of ciphers themselves 2) aliases for groups of ciphers.
 845          * For 1) we need the available ciphers and for 2) the cipher
 846          * groups of cipher_aliases added together in one list (otherwise
 847          * we would be happy with just the cipher_aliases table).
 848          */
 849         num_of_group_aliases = sizeof(cipher_aliases) / sizeof(SSL_CIPHER);
 850         num_of_alias_max = num_of_ciphers + num_of_group_aliases + 1;
 851         ca_list =
 852                 (SSL_CIPHER **)OPENSSL_malloc(sizeof(SSL_CIPHER *) * num_of_alias_max);
 853         if (ca_list == NULL)
 854                 {
 855                 OPENSSL_free(co_list);
 856                 SSLerr(SSL_F_SSL_CREATE_CIPHER_LIST,ERR_R_MALLOC_FAILURE);
 857                 return(NULL);   /* Failure */
 858                 }
 859         ssl_cipher_collect_aliases(ca_list, num_of_group_aliases, disabled_mask,
 860                                    head);
 861
 862         /*
 863          * If the rule_string begins with DEFAULT, apply the default rule
 864          * before using the (possibly available) additional rules.
 865          */
 866         ok = 1;
 867         rule_p = rule_str;
 868         if (strncmp(rule_str,"DEFAULT",7) == 0)
 869                 {
 870                 ok = ssl_cipher_process_rulestr(SSL_DEFAULT_CIPHER_LIST,
 871                         co_list, &head, &tail, ca_list);
 872                 rule_p += 7;
 873                 if (*rule_p == ':')
 874                         rule_p++;
 875                 }
 876
 877         if (ok && (strlen(rule_p) > 0))
 878                 ok = ssl_cipher_process_rulestr(rule_p, co_list, &head, &tail,
 879                                                 ca_list);
 880
 881         OPENSSL_free(ca_list);  /* Not needed anymore */
 882
 883         if (!ok)
 884                 {       /* Rule processing failure */
 885                 OPENSSL_free(co_list);
 886                 return(NULL);
 887                 }
 888         /*
 889          * Allocate new "cipherstack" for the result, return with error
 890          * if we cannot get one.
 891          */
 892         if ((cipherstack = sk_SSL_CIPHER_new_null()) == NULL)
 893                 {
 894                 OPENSSL_free(co_list);
 895                 return(NULL);
 896                 }
 897
 898         /*
 899          * The cipher selection for the list is done. The ciphers are added
 900          * to the resulting precedence to the STACK_OF(SSL_CIPHER).
 901          */
 902         for (curr = head; curr != NULL; curr = curr->next)
 903                 {
 904                 if (curr->active)
 905                         {
 906                         sk_SSL_CIPHER_push(cipherstack, curr->cipher);
 907 #ifdef CIPHER_DEBUG
 908                         printf("<%s>\n",curr->cipher->name);
 909 #endif
 910                         }
 911                 }
 912         OPENSSL_free(co_list);  /* Not needed any longer */
 913
 914         tmp_cipher_list = sk_SSL_CIPHER_dup(cipherstack);
 915         if (tmp_cipher_list == NULL)
 916                 {
 917                 sk_SSL_CIPHER_free(cipherstack);
 918                 return NULL;
 919                 }
 920         if (*cipher_list != NULL)
 921                 sk_SSL_CIPHER_free(*cipher_list);
 922         *cipher_list = cipherstack;
 923         if (*cipher_list_by_id != NULL)
 924                 sk_SSL_CIPHER_free(*cipher_list_by_id);
 925         *cipher_list_by_id = tmp_cipher_list;
 926         sk_SSL_CIPHER_set_cmp_func(*cipher_list_by_id,ssl_cipher_ptr_id_cmp);
 927
 928         return(cipherstack);
 929         }
 930
 931 char *SSL_CIPHER_description(SSL_CIPHER *cipher, char *buf, int len)
 932         {
 933         int is_export,pkl,kl;
 934         const char *ver,*exp_str;
 935         const char *kx,*au,*enc,*mac;
 936         unsigned long alg,alg2,alg_s;
 937 #ifdef KSSL_DEBUG
 938         static const char *format="%-23s %s Kx=%-8s Au=%-4s Enc=%-9s Mac=%-4s%s AL=%lx\n";
 939 #else
 940         static const char *format="%-23s %s Kx=%-8s Au=%-4s Enc=%-9s Mac=%-4s%s\n";
 941 #endif /* KSSL_DEBUG */
 942
 943         alg=cipher->algorithms;
 944         alg_s=cipher->algo_strength;
 945         alg2=cipher->algorithm2;
 946
 947         is_export=SSL_C_IS_EXPORT(cipher);
 948         pkl=SSL_C_EXPORT_PKEYLENGTH(cipher);
 949         kl=SSL_C_EXPORT_KEYLENGTH(cipher);
 950         exp_str=is_export?" export":"";
 951
 952         if (alg & SSL_SSLV2)
 953                 ver="SSLv2";
 954         else if (alg & SSL_SSLV3)
 955                 ver="SSLv3";
 956         else
 957                 ver="unknown";
 958
 959         switch (alg&SSL_MKEY_MASK)
 960                 {
 961         case SSL_kRSA:
 962                 kx=is_export?(pkl == 512 ? "RSA(512)" : "RSA(1024)"):"RSA";
 963                 break;
 964         case SSL_kDHr:
 965                 kx="DH/RSA";
 966                 break;
 967         case SSL_kDHd:
 968                 kx="DH/DSS";
 969                 break;
 970         case SSL_kKRB5:         /* VRS */
 971         case SSL_KRB5:          /* VRS */
 972             kx="KRB5";
 973             break;
 974         case SSL_kFZA:
 975                 kx="Fortezza";
 976                 break;
 977         case SSL_kEDH:
 978                 kx=is_export?(pkl == 512 ? "DH(512)" : "DH(1024)"):"DH";
 979                 break;
 980         case SSL_kECDH:
 981         case SSL_kECDHE:
 982                 kx=is_export?"ECDH(<=163)":"ECDH";
 983                 break;
 984         default:
 985                 kx="unknown";
 986                 }
 987
 988         switch (alg&SSL_AUTH_MASK)
 989                 {
 990         case SSL_aRSA:
 991                 au="RSA";
 992                 break;
 993         case SSL_aDSS:
 994                 au="DSS";
 995                 break;
 996         case SSL_aDH:
 997                 au="DH";
 998                 break;
 999         case SSL_aKRB5:         /* VRS */
1000         case SSL_KRB5:          /* VRS */
1001             au="KRB5";
1002             break;
1003         case SSL_aFZA:
1004         case SSL_aNULL:
1005                 au="None";
1006                 break;
1007         case SSL_aECDSA:
1008                 au="ECDSA";
1009                 break;
1010         default:
1011                 au="unknown";
1012                 break;
1013                 }
1014
1015         switch (alg&SSL_ENC_MASK)
1016                 {
1017         case SSL_DES:
1018                 enc=(is_export && kl == 5)?"DES(40)":"DES(56)";
1019                 break;
1020         case SSL_3DES:
1021                 enc="3DES(168)";
1022                 break;
1023         case SSL_RC4:
1024                 enc=is_export?(kl == 5 ? "RC4(40)" : "RC4(56)")
1025                   :((alg2&SSL2_CF_8_BYTE_ENC)?"RC4(64)":"RC4(128)");
1026                 break;
1027         case SSL_RC2:
1028                 enc=is_export?(kl == 5 ? "RC2(40)" : "RC2(56)"):"RC2(128)";
1029                 break;
1030         case SSL_IDEA:
1031                 enc="IDEA(128)";
1032                 break;
1033         case SSL_eFZA:
1034                 enc="Fortezza";
1035                 break;
1036         case SSL_eNULL:
1037                 enc="None";
1038                 break;
1039         case SSL_AES:
1040                 switch(cipher->strength_bits)
1041                         {
1042                 case 128: enc="AES(128)"; break;
1043                 case 192: enc="AES(192)"; break;
1044                 case 256: enc="AES(256)"; break;
1045                 default: enc="AES(?""?""?)"; break;
1046                         }
1047                 break;
1048         default:
1049                 enc="unknown";
1050                 break;
1051                 }
1052
1053         switch (alg&SSL_MAC_MASK)
1054                 {
1055         case SSL_MD5:
1056                 mac="MD5";
1057                 break;
1058         case SSL_SHA1:
1059                 mac="SHA1";
1060                 break;
1061         default:
1062                 mac="unknown";
1063                 break;
1064                 }
1065
1066         if (buf == NULL)
1067                 {
1068                 len=128;
1069                 buf=OPENSSL_malloc(len);
1070                 if (buf == NULL) return("OPENSSL_malloc Error");
1071                 }
1072         else if (len < 128)
1073                 return("Buffer too small");
1074
1075 #ifdef KSSL_DEBUG
1076         BIO_snprintf(buf,len,format,cipher->name,ver,kx,au,enc,mac,exp_str,alg);
1077 #else
1078         BIO_snprintf(buf,len,format,cipher->name,ver,kx,au,enc,mac,exp_str);
1079 #endif /* KSSL_DEBUG */
1080         return(buf);
1081         }
1082
1083 char *SSL_CIPHER_get_version(const SSL_CIPHER *c)
1084         {
1085         int i;
1086
1087         if (c == NULL) return("(NONE)");
1088         i=(int)(c->id>>24L);
1089         if (i == 3)
1090                 return("TLSv1/SSLv3");
1091         else if (i == 2)
1092                 return("SSLv2");
1093         else
1094                 return("unknown");
1095         }
1096
1097 /* return the actual cipher being used */
1098 const char *SSL_CIPHER_get_name(const SSL_CIPHER *c)
1099         {
1100         if (c != NULL)
1101                 return(c->name);
1102         return("(NONE)");
1103         }
1104
1105 /* number of bits for symmetric cipher */
1106 int SSL_CIPHER_get_bits(const SSL_CIPHER *c, int *alg_bits)
1107         {
1108         int ret=0;
1109
1110         if (c != NULL)
1111                 {
1112                 if (alg_bits != NULL) *alg_bits = c->alg_bits;
1113                 ret = c->strength_bits;
1114                 }
1115         return(ret);
1116         }
1117
1118 SSL_COMP *ssl3_comp_find(STACK_OF(SSL_COMP) *sk, int n)
1119         {
1120         SSL_COMP *ctmp;
1121         int i,nn;
1122
1123         if ((n == 0) || (sk == NULL)) return(NULL);
1124         nn=sk_SSL_COMP_num(sk);
1125         for (i=0; i<nn; i++)
1126                 {
1127                 ctmp=sk_SSL_COMP_value(sk,i);
1128                 if (ctmp->id == n)
1129                         return(ctmp);
1130                 }
1131         return(NULL);
1132         }
1133
1134 STACK_OF(SSL_COMP) *SSL_COMP_get_compression_methods(void)
1135         {
1136         load_builtin_compressions();
1137         return(ssl_comp_methods);
1138         }
1139
1140 int SSL_COMP_add_compression_method(int id, COMP_METHOD *cm)
1141         {
1142         SSL_COMP *comp;
1143
1144         if (cm == NULL || cm->type == NID_undef)
1145                 return 1;
1146
1147         /* According to draft-ietf-tls-compression-04.txt, the
1148            compression number ranges should be the following:
1149
1150            0 to 63:    methods defined by the IETF
1151            64 to 192:  external party methods assigned by IANA
1152            193 to 255: reserved for private use */
1153         if (id < 193 || id > 255)
1154                 {
1155                 SSLerr(SSL_F_SSL_COMP_ADD_COMPRESSION_METHOD,SSL_R_COMPRESSION_ID_NOT_WITHIN_PRIVATE_RANGE);
1156                 return 0;
1157                 }
1158
1159         MemCheck_off();
1160         comp=(SSL_COMP *)OPENSSL_malloc(sizeof(SSL_COMP));
1161         comp->id=id;
1162         comp->method=cm;
1163         load_builtin_compressions();
1164         if (ssl_comp_methods
1165                 && !sk_SSL_COMP_find(ssl_comp_methods,comp))
1166                 {
1167                 OPENSSL_free(comp);
1168                 MemCheck_on();
1169                 SSLerr(SSL_F_SSL_COMP_ADD_COMPRESSION_METHOD,SSL_R_DUPLICATE_COMPRESSION_ID);
1170                 return(1);
1171                 }
1172         else if ((ssl_comp_methods == NULL)
1173                 || !sk_SSL_COMP_push(ssl_comp_methods,comp))
1174                 {
1175                 OPENSSL_free(comp);
1176                 MemCheck_on();
1177                 SSLerr(SSL_F_SSL_COMP_ADD_COMPRESSION_METHOD,ERR_R_MALLOC_FAILURE);
1178                 return(1);
1179                 }
1180         else
1181                 {
1182                 MemCheck_on();
1183                 return(0);
1184                 }
1185         }
1186
1187 const char *SSL_COMP_get_name(const COMP_METHOD *comp)
1188         {
1189         if (comp)
1190                 return comp->name;
1191         return NULL;
1192         }
1193