lib/krb5/salt.c

   1 /*
   2  * Copyright (c) 1997 - 2008 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include "krb5_locl.h"
  35
  36 /* coverity[+alloc : arg-*3] */
  37 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
  38 krb5_salttype_to_string (krb5_context context,
  39                          krb5_enctype etype,
  40                          krb5_salttype stype,
  41                          char **string)
  42 {
  43     struct _krb5_encryption_type *e;
  44     struct salt_type *st;
  45
  46     *string = NULL;
  47     e = _krb5_find_enctype (etype);
  48     if (e == NULL) {
  49         krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
  50                                "encryption type %d not supported",
  51                                etype);
  52         return KRB5_PROG_ETYPE_NOSUPP;
  53     }
  54     for (st = e->keytype->string_to_key; st && st->type; st++) {
  55         if (st->type == stype) {
  56             *string = strdup (st->name);
  57             if (*string == NULL)
  58                 return krb5_enomem(context);
  59             return 0;
  60         }
  61     }
  62     krb5_set_error_message (context, HEIM_ERR_SALTTYPE_NOSUPP,
  63                             "salttype %d not supported", stype);
  64     return HEIM_ERR_SALTTYPE_NOSUPP;
  65 }
  66
  67 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
  68 krb5_string_to_salttype (krb5_context context,
  69                          krb5_enctype etype,
  70                          const char *string,
  71                          krb5_salttype *salttype)
  72 {
  73     struct _krb5_encryption_type *e;
  74     struct salt_type *st;
  75
  76     e = _krb5_find_enctype (etype);
  77     if (e == NULL) {
  78         krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
  79                                N_("encryption type %d not supported", ""),
  80                                etype);
  81         return KRB5_PROG_ETYPE_NOSUPP;
  82     }
  83     for (st = e->keytype->string_to_key; st && st->type; st++) {
  84         if (strcasecmp (st->name, string) == 0) {
  85             *salttype = st->type;
  86             return 0;
  87         }
  88     }
  89     krb5_set_error_message(context, HEIM_ERR_SALTTYPE_NOSUPP,
  90                            N_("salttype %s not supported", ""), string);
  91     return HEIM_ERR_SALTTYPE_NOSUPP;
  92 }
  93
  94 /*
  95  * Like MIT's krb5_string_to_keysalts(), but simpler and with a context
  96  * argument.
  97  */
  98 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
  99 krb5_string_to_keysalts2(krb5_context context, const char *string,
 100                          size_t *nksaltp, krb5_key_salt_tuple **ksaltp)
 101 {
 102     /* deleted: tupleseps, ksaltseps, dups */
 103     krb5_key_salt_tuple *tmp = NULL;
 104     krb5_error_code ret = 0;
 105     char *copy, *token, *stype_str;
 106     char *lasts = NULL;
 107     krb5_enctype etype;
 108     krb5_salttype stype;
 109     size_t i;
 110
 111     *ksaltp = NULL;
 112     *nksaltp = 0;
 113     if ((copy = strdup(string)) == NULL)
 114         return krb5_enomem(context);
 115     for (token = strtok_r(copy, ", \t", &lasts), ret = 0;
 116          token != NULL;
 117          token = strtok_r(NULL, ", \t", &lasts)) {
 118         if ((stype_str = strchr(token, ':')) != NULL)
 119             *(stype_str++) = '\0';
 120         if ((ret = krb5_string_to_enctype(context, token, &etype)))
 121             continue;
 122         if (stype_str == NULL)
 123             stype = KRB5_PW_SALT;
 124         else if ((ret = krb5_string_to_salttype(context, etype, stype_str, &stype)))
 125             continue;
 126         for (i = 0; i < *nksaltp; i++) {
 127             if ((*ksaltp)[i].ks_enctype == etype &&
 128                 (*ksaltp)[i].ks_salttype == stype)
 129                 goto skip;
 130         }
 131         tmp = realloc(*ksaltp, ((*nksaltp) + 1) * sizeof(**ksaltp));
 132         if (tmp == NULL) {
 133             ret = krb5_enomem(context);
 134             break;
 135         }
 136         *ksaltp = tmp;
 137         (*ksaltp)[*nksaltp].ks_enctype = etype;
 138         (*ksaltp)[*nksaltp].ks_salttype = stype;
 139         (*nksaltp)++;
 140 skip:
 141         (void)1;
 142     }
 143     free(copy);
 144     if (ret == ENOMEM) {
 145         free(*ksaltp);
 146         *nksaltp = 0;
 147         *ksaltp = NULL;
 148     } else if (*nksaltp) {
 149         return 0;
 150     } else if (ret == 0) {
 151         return KRB5_PROG_ETYPE_NOSUPP;
 152     }
 153     return ret;
 154 }
 155
 156
 157 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 158 krb5_get_pw_salt(krb5_context context,
 159                  krb5_const_principal principal,
 160                  krb5_salt *salt)
 161 {
 162     size_t len;
 163     size_t i;
 164     krb5_error_code ret;
 165     char *p;
 166
 167     salt->salttype = KRB5_PW_SALT;
 168     len = strlen(principal->realm);
 169     for (i = 0; i < principal->name.name_string.len; ++i)
 170         len += strlen(principal->name.name_string.val[i]);
 171     ret = krb5_data_alloc (&salt->saltvalue, len);
 172     if (ret)
 173         return ret;
 174     p = salt->saltvalue.data;
 175     memcpy (p, principal->realm, strlen(principal->realm));
 176     p += strlen(principal->realm);
 177     for (i = 0; i < principal->name.name_string.len; ++i) {
 178         memcpy (p,
 179                 principal->name.name_string.val[i],
 180                 strlen(principal->name.name_string.val[i]));
 181         p += strlen(principal->name.name_string.val[i]);
 182     }
 183     return 0;
 184 }
 185
 186 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 187 krb5_free_salt(krb5_context context,
 188                krb5_salt salt)
 189 {
 190     krb5_data_free(&salt.saltvalue);
 191     return 0;
 192 }
 193
 194 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 195 krb5_string_to_key_data (krb5_context context,
 196                          krb5_enctype enctype,
 197                          krb5_data password,
 198                          krb5_const_principal principal,
 199                          krb5_keyblock *key)
 200 {
 201     krb5_error_code ret;
 202     krb5_salt salt;
 203
 204     ret = krb5_get_pw_salt(context, principal, &salt);
 205     if(ret)
 206         return ret;
 207     ret = krb5_string_to_key_data_salt(context, enctype, password, salt, key);
 208     krb5_free_salt(context, salt);
 209     return ret;
 210 }
 211
 212 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 213 krb5_string_to_key (krb5_context context,
 214                     krb5_enctype enctype,
 215                     const char *password,
 216                     krb5_const_principal principal,
 217                     krb5_keyblock *key)
 218 {
 219     krb5_data pw;
 220     pw.data = rk_UNCONST(password);
 221     pw.length = strlen(password);
 222     return krb5_string_to_key_data(context, enctype, pw, principal, key);
 223 }
 224
 225 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 226 krb5_string_to_key_data_salt (krb5_context context,
 227                               krb5_enctype enctype,
 228                               krb5_data password,
 229                               krb5_salt salt,
 230                               krb5_keyblock *key)
 231 {
 232     krb5_data opaque;
 233     krb5_data_zero(&opaque);
 234     return krb5_string_to_key_data_salt_opaque(context, enctype, password,
 235                                                salt, opaque, key);
 236 }
 237
 238 /*
 239  * Do a string -> key for encryption type `enctype' operation on
 240  * `password' (with salt `salt' and the enctype specific data string
 241  * `opaque'), returning the resulting key in `key'
 242  */
 243
 244 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 245 krb5_string_to_key_data_salt_opaque (krb5_context context,
 246                                      krb5_enctype enctype,
 247                                      krb5_data password,
 248                                      krb5_salt salt,
 249                                      krb5_data opaque,
 250                                      krb5_keyblock *key)
 251 {
 252     struct _krb5_encryption_type *et =_krb5_find_enctype(enctype);
 253     struct salt_type *st;
 254     if(et == NULL) {
 255         krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
 256                                N_("encryption type %d not supported", ""),
 257                                enctype);
 258         return KRB5_PROG_ETYPE_NOSUPP;
 259     }
 260     for(st = et->keytype->string_to_key; st && st->type; st++)
 261         if(st->type == salt.salttype)
 262             return (*st->string_to_key)(context, enctype, password,
 263                                         salt, opaque, key);
 264     krb5_set_error_message(context, HEIM_ERR_SALTTYPE_NOSUPP,
 265                            N_("salt type %d not supported", ""),
 266                            salt.salttype);
 267     return HEIM_ERR_SALTTYPE_NOSUPP;
 268 }
 269
 270 /*
 271  * Do a string -> key for encryption type `enctype' operation on the
 272  * string `password' (with salt `salt'), returning the resulting key
 273  * in `key'
 274  */
 275
 276 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 277 krb5_string_to_key_salt (krb5_context context,
 278                          krb5_enctype enctype,
 279                          const char *password,
 280                          krb5_salt salt,
 281                          krb5_keyblock *key)
 282 {
 283     krb5_data pw;
 284     pw.data = rk_UNCONST(password);
 285     pw.length = strlen(password);
 286     return krb5_string_to_key_data_salt(context, enctype, pw, salt, key);
 287 }
 288
 289 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 290 krb5_string_to_key_salt_opaque (krb5_context context,
 291                                 krb5_enctype enctype,
 292                                 const char *password,
 293                                 krb5_salt salt,
 294                                 krb5_data opaque,
 295                                 krb5_keyblock *key)
 296 {
 297     krb5_data pw;
 298     pw.data = rk_UNCONST(password);
 299     pw.length = strlen(password);
 300     return krb5_string_to_key_data_salt_opaque(context, enctype,
 301                                                pw, salt, opaque, key);
 302 }
 303
 304
 305 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 306 krb5_string_to_key_derived(krb5_context context,
 307                            const void *str,
 308                            size_t len,
 309                            krb5_enctype etype,
 310                            krb5_keyblock *key)
 311 {
 312     struct _krb5_encryption_type *et = _krb5_find_enctype(etype);
 313     krb5_error_code ret;
 314     struct _krb5_key_data kd;
 315     size_t keylen;
 316     u_char *tmp;
 317
 318     if(et == NULL) {
 319         krb5_set_error_message (context, KRB5_PROG_ETYPE_NOSUPP,
 320                                 N_("encryption type %d not supported", ""),
 321                                 etype);
 322         return KRB5_PROG_ETYPE_NOSUPP;
 323     }
 324     keylen = et->keytype->bits / 8;
 325
 326     ALLOC(kd.key, 1);
 327     if (kd.key == NULL)
 328         return krb5_enomem(context);
 329     ret = krb5_data_alloc(&kd.key->keyvalue, et->keytype->size);
 330     if(ret) {
 331         free(kd.key);
 332         return ret;
 333     }
 334     kd.key->keytype = etype;
 335     tmp = malloc (keylen);
 336     if(tmp == NULL) {
 337         krb5_free_keyblock(context, kd.key);
 338         return krb5_enomem(context);
 339     }
 340     ret = _krb5_n_fold(str, len, tmp, keylen);
 341     if (ret) {
 342         free(tmp);
 343         krb5_enomem(context);
 344         return ret;
 345     }
 346     kd.schedule = NULL;
 347     _krb5_DES3_random_to_key(context, kd.key, tmp, keylen);
 348     memset(tmp, 0, keylen);
 349     free(tmp);
 350     ret = _krb5_derive_key(context,
 351                            et,
 352                            &kd,
 353                            "kerberos", /* XXX well known constant */
 354                            strlen("kerberos"));
 355     if (ret) {
 356         _krb5_free_key_data(context, &kd, et);
 357         return ret;
 358     }
 359     ret = krb5_copy_keyblock_contents(context, kd.key, key);
 360     _krb5_free_key_data(context, &kd, et);
 361     return ret;
 362 }