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     e = _krb5_find_enctype (etype);
  47     if (e == NULL) {
  48         krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
  49                                "encryption type %d not supported",
  50                                etype);
  51         return KRB5_PROG_ETYPE_NOSUPP;
  52     }
  53     for (st = e->keytype->string_to_key; st && st->type; st++) {
  54         if (st->type == stype) {
  55             *string = strdup (st->name);
  56             if (*string == NULL) {
  57                 krb5_set_error_message (context, ENOMEM,
  58                                         N_("malloc: out of memory", ""));
  59                 return ENOMEM;
  60             }
  61             return 0;
  62         }
  63     }
  64     krb5_set_error_message (context, HEIM_ERR_SALTTYPE_NOSUPP,
  65                             "salttype %d not supported", stype);
  66     return HEIM_ERR_SALTTYPE_NOSUPP;
  67 }
  68
  69 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
  70 krb5_string_to_salttype (krb5_context context,
  71                          krb5_enctype etype,
  72                          const char *string,
  73                          krb5_salttype *salttype)
  74 {
  75     struct _krb5_encryption_type *e;
  76     struct salt_type *st;
  77
  78     e = _krb5_find_enctype (etype);
  79     if (e == NULL) {
  80         krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
  81                                N_("encryption type %d not supported", ""),
  82                                etype);
  83         return KRB5_PROG_ETYPE_NOSUPP;
  84     }
  85     for (st = e->keytype->string_to_key; st && st->type; st++) {
  86         if (strcasecmp (st->name, string) == 0) {
  87             *salttype = st->type;
  88             return 0;
  89         }
  90     }
  91     krb5_set_error_message(context, HEIM_ERR_SALTTYPE_NOSUPP,
  92                            N_("salttype %s not supported", ""), string);
  93     return HEIM_ERR_SALTTYPE_NOSUPP;
  94 }
  95
  96 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
  97 krb5_get_pw_salt(krb5_context context,
  98                  krb5_const_principal principal,
  99                  krb5_salt *salt)
 100 {
 101     size_t len;
 102     size_t i;
 103     krb5_error_code ret;
 104     char *p;
 105
 106     salt->salttype = KRB5_PW_SALT;
 107     len = strlen(principal->realm);
 108     for (i = 0; i < principal->name.name_string.len; ++i)
 109         len += strlen(principal->name.name_string.val[i]);
 110     ret = krb5_data_alloc (&salt->saltvalue, len);
 111     if (ret)
 112         return ret;
 113     p = salt->saltvalue.data;
 114     memcpy (p, principal->realm, strlen(principal->realm));
 115     p += strlen(principal->realm);
 116     for (i = 0; i < principal->name.name_string.len; ++i) {
 117         memcpy (p,
 118                 principal->name.name_string.val[i],
 119                 strlen(principal->name.name_string.val[i]));
 120         p += strlen(principal->name.name_string.val[i]);
 121     }
 122     return 0;
 123 }
 124
 125 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 126 krb5_free_salt(krb5_context context,
 127                krb5_salt salt)
 128 {
 129     krb5_data_free(&salt.saltvalue);
 130     return 0;
 131 }
 132
 133 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 134 krb5_string_to_key_data (krb5_context context,
 135                          krb5_enctype enctype,
 136                          krb5_data password,
 137                          krb5_principal principal,
 138                          krb5_keyblock *key)
 139 {
 140     krb5_error_code ret;
 141     krb5_salt salt;
 142
 143     ret = krb5_get_pw_salt(context, principal, &salt);
 144     if(ret)
 145         return ret;
 146     ret = krb5_string_to_key_data_salt(context, enctype, password, salt, key);
 147     krb5_free_salt(context, salt);
 148     return ret;
 149 }
 150
 151 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 152 krb5_string_to_key (krb5_context context,
 153                     krb5_enctype enctype,
 154                     const char *password,
 155                     krb5_principal principal,
 156                     krb5_keyblock *key)
 157 {
 158     krb5_data pw;
 159     pw.data = rk_UNCONST(password);
 160     pw.length = strlen(password);
 161     return krb5_string_to_key_data(context, enctype, pw, principal, key);
 162 }
 163
 164 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 165 krb5_string_to_key_data_salt (krb5_context context,
 166                               krb5_enctype enctype,
 167                               krb5_data password,
 168                               krb5_salt salt,
 169                               krb5_keyblock *key)
 170 {
 171     krb5_data opaque;
 172     krb5_data_zero(&opaque);
 173     return krb5_string_to_key_data_salt_opaque(context, enctype, password,
 174                                                salt, opaque, key);
 175 }
 176
 177 /*
 178  * Do a string -> key for encryption type `enctype' operation on
 179  * `password' (with salt `salt' and the enctype specific data string
 180  * `opaque'), returning the resulting key in `key'
 181  */
 182
 183 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 184 krb5_string_to_key_data_salt_opaque (krb5_context context,
 185                                      krb5_enctype enctype,
 186                                      krb5_data password,
 187                                      krb5_salt salt,
 188                                      krb5_data opaque,
 189                                      krb5_keyblock *key)
 190 {
 191     struct _krb5_encryption_type *et =_krb5_find_enctype(enctype);
 192     struct salt_type *st;
 193     if(et == NULL) {
 194         krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP,
 195                                N_("encryption type %d not supported", ""),
 196                                enctype);
 197         return KRB5_PROG_ETYPE_NOSUPP;
 198     }
 199     for(st = et->keytype->string_to_key; st && st->type; st++)
 200         if(st->type == salt.salttype)
 201             return (*st->string_to_key)(context, enctype, password,
 202                                         salt, opaque, key);
 203     krb5_set_error_message(context, HEIM_ERR_SALTTYPE_NOSUPP,
 204                            N_("salt type %d not supported", ""),
 205                            salt.salttype);
 206     return HEIM_ERR_SALTTYPE_NOSUPP;
 207 }
 208
 209 /*
 210  * Do a string -> key for encryption type `enctype' operation on the
 211  * string `password' (with salt `salt'), returning the resulting key
 212  * in `key'
 213  */
 214
 215 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 216 krb5_string_to_key_salt (krb5_context context,
 217                          krb5_enctype enctype,
 218                          const char *password,
 219                          krb5_salt salt,
 220                          krb5_keyblock *key)
 221 {
 222     krb5_data pw;
 223     pw.data = rk_UNCONST(password);
 224     pw.length = strlen(password);
 225     return krb5_string_to_key_data_salt(context, enctype, pw, salt, key);
 226 }
 227
 228 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 229 krb5_string_to_key_salt_opaque (krb5_context context,
 230                                 krb5_enctype enctype,
 231                                 const char *password,
 232                                 krb5_salt salt,
 233                                 krb5_data opaque,
 234                                 krb5_keyblock *key)
 235 {
 236     krb5_data pw;
 237     pw.data = rk_UNCONST(password);
 238     pw.length = strlen(password);
 239     return krb5_string_to_key_data_salt_opaque(context, enctype,
 240                                                pw, salt, opaque, key);
 241 }
 242
 243
 244 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 245 krb5_string_to_key_derived(krb5_context context,
 246                            const void *str,
 247                            size_t len,
 248                            krb5_enctype etype,
 249                            krb5_keyblock *key)
 250 {
 251     struct _krb5_encryption_type *et = _krb5_find_enctype(etype);
 252     krb5_error_code ret;
 253     struct _krb5_key_data kd;
 254     size_t keylen;
 255     u_char *tmp;
 256
 257     if(et == NULL) {
 258         krb5_set_error_message (context, KRB5_PROG_ETYPE_NOSUPP,
 259                                 N_("encryption type %d not supported", ""),
 260                                 etype);
 261         return KRB5_PROG_ETYPE_NOSUPP;
 262     }
 263     keylen = et->keytype->bits / 8;
 264
 265     ALLOC(kd.key, 1);
 266     if(kd.key == NULL) {
 267         krb5_set_error_message (context, ENOMEM,
 268                                 N_("malloc: out of memory", ""));
 269         return ENOMEM;
 270     }
 271     ret = krb5_data_alloc(&kd.key->keyvalue, et->keytype->size);
 272     if(ret) {
 273         free(kd.key);
 274         return ret;
 275     }
 276     kd.key->keytype = etype;
 277     tmp = malloc (keylen);
 278     if(tmp == NULL) {
 279         krb5_free_keyblock(context, kd.key);
 280         krb5_set_error_message (context, ENOMEM, N_("malloc: out of memory", ""));
 281         return ENOMEM;
 282     }
 283     ret = _krb5_n_fold(str, len, tmp, keylen);
 284     if (ret) {
 285         free(tmp);
 286         krb5_set_error_message (context, ENOMEM, N_("malloc: out of memory", ""));
 287         return ret;
 288     }
 289     kd.schedule = NULL;
 290     _krb5_DES3_random_to_key(context, kd.key, tmp, keylen);
 291     memset(tmp, 0, keylen);
 292     free(tmp);
 293     ret = _krb5_derive_key(context,
 294                            et,
 295                            &kd,
 296                            "kerberos", /* XXX well known constant */
 297                            strlen("kerberos"));
 298     if (ret) {
 299         _krb5_free_key_data(context, &kd, et);
 300         return ret;
 301     }
 302     ret = krb5_copy_keyblock_contents(context, kd.key, key);
 303     _krb5_free_key_data(context, &kd, et);
 304     return ret;
 305 }