lib/pkcs11_privkey.c

   1 /*
   2  * GnuTLS PKCS#11 support
   3  * Copyright (C) 2010 Free Software Foundation
   4  *
   5  * Author: Nikos Mavrogiannopoulos
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Library General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Library General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Library General Public
  18  * License along with this library; if not, write to the Free
  19  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  20  * MA 02111-1307, USA
  21 */
  22
  23 #include <gnutls_int.h>
  24 #include <pakchois/pakchois.h>
  25 #include <gnutls/pkcs11.h>
  26 #include <stdio.h>
  27 #include <stdbool.h>
  28 #include <string.h>
  29 #include <gnutls_errors.h>
  30 #include <gnutls_datum.h>
  31 #include <pkcs11_int.h>
  32 #include <gnutls_sig.h>
  33
  34 struct gnutls_pkcs11_privkey_st
  35 {
  36   gnutls_pk_algorithm_t pk_algorithm;
  37   unsigned int flags;
  38   struct pkcs11_url_info info;
  39 };
  40
  41 /**
  42  * gnutls_pkcs11_privkey_init:
  43  * @key: The structure to be initialized
  44  *
  45  * This function will initialize an private key structure.
  46  *
  47  * Returns: On success, %GNUTLS_E_SUCCESS is returned, otherwise a
  48  *   negative error value.
  49  **/
  50 int
  51 gnutls_pkcs11_privkey_init (gnutls_pkcs11_privkey_t * key)
  52 {
  53   *key = gnutls_calloc (1, sizeof (struct gnutls_pkcs11_privkey_st));
  54   if (*key == NULL)
  55     {
  56       gnutls_assert ();
  57       return GNUTLS_E_MEMORY_ERROR;
  58     }
  59
  60   return 0;
  61 }
  62
  63 /**
  64  * gnutls_pkcs11_privkey_deinit:
  65  * @key: The structure to be initialized
  66  *
  67  * This function will deinitialize a private key structure.
  68  **/
  69 void
  70 gnutls_pkcs11_privkey_deinit (gnutls_pkcs11_privkey_t key)
  71 {
  72   gnutls_free (key);
  73 }
  74
  75 /**
  76  * gnutls_pkcs11_privkey_get_pk_algorithm:
  77  * @key: should contain a #gnutls_pkcs11_privkey_t structure
  78  *
  79  * This function will return the public key algorithm of a private
  80  * key.
  81  *
  82  * Returns: a member of the #gnutls_pk_algorithm_t enumeration on
  83  *   success, or a negative value on error.
  84  **/
  85 int
  86 gnutls_pkcs11_privkey_get_pk_algorithm (gnutls_pkcs11_privkey_t key,
  87                                         unsigned int *bits)
  88 {
  89   if (bits)
  90     *bits = 0;                  /* FIXME */
  91   return key->pk_algorithm;
  92 }
  93
  94 /**
  95  * gnutls_pkcs11_privkey_get_info:
  96  * @key: should contain a #gnutls_pkcs11_privkey_t structure
  97  * @itype: Denotes the type of information requested
  98  * @output: where output will be stored
  99  * @output_size: contains the maximum size of the output and will be overwritten with actual
 100  *
 101  * This function will return information about the PKCS 11 private key such
 102  * as the label, id as well as token information where the key is stored. When
 103  * output is text it returns null terminated string although #output_size contains
 104  * the size of the actual data only.
 105  *
 106  * Returns: zero on success or a negative value on error.
 107  **/
 108 int
 109 gnutls_pkcs11_privkey_get_info (gnutls_pkcs11_privkey_t pkey,
 110                                 gnutls_pkcs11_obj_info_t itype,
 111                                 void *output, size_t * output_size)
 112 {
 113   return pkcs11_get_info (&pkey->info, itype, output, output_size);
 114 }
 115
 116
 117 #define FIND_OBJECT(pks, obj, key) \
 118         do { \
 119                 int retries = 0; \
 120                 int rret; \
 121                 ret = pkcs11_find_object (&pks, &obj, &key->info, \
 122                         SESSION_LOGIN); \
 123                 if (ret < 0) { \
 124                         rret = token_func(token_data, key->info.token, retries++); \
 125                         if (rret == 0) continue; \
 126                         gnutls_assert(); \
 127                         return ret; \
 128                 } \
 129         } while (ret < 0);
 130
 131 /*-
 132  * _gnutls_pkcs11_privkey_sign_hash:
 133  * @key: Holds the key
 134  * @hash: holds the data to be signed (should be output of a hash)
 135  * @signature: will contain the signature allocated with gnutls_malloc()
 136  *
 137  * This function will sign the given data using a signature algorithm
 138  * supported by the private key. It is assumed that the given data
 139  * are the output of a hash function.
 140  *
 141  * Returns: On success, %GNUTLS_E_SUCCESS is returned, otherwise a
 142  *   negative error value.
 143  -*/
 144 int
 145 _gnutls_pkcs11_privkey_sign_hash (gnutls_pkcs11_privkey_t key,
 146                                   const gnutls_datum_t * hash,
 147                                   gnutls_datum_t * signature)
 148 {
 149   ck_rv_t rv;
 150   int ret;
 151   struct ck_mechanism mech;
 152   unsigned long siglen;
 153   pakchois_session_t *pks;
 154   ck_object_handle_t obj;
 155
 156   FIND_OBJECT (pks, obj, key);
 157
 158   mech.mechanism =
 159     key->pk_algorithm == GNUTLS_PK_DSA ? CKM_DSA : CKM_RSA_PKCS;
 160   mech.parameter = NULL;
 161   mech.parameter_len = 0;
 162
 163   /* Initialize signing operation; using the private key discovered
 164    * earlier. */
 165   rv = pakchois_sign_init (pks, &mech, obj);
 166   if (rv != CKR_OK)
 167     {
 168       gnutls_assert ();
 169       ret = pkcs11_rv_to_err (rv);
 170       goto cleanup;
 171     }
 172
 173   /* Work out how long the signature must be: */
 174   rv = pakchois_sign (pks, hash->data, hash->size, NULL, &siglen);
 175   if (rv != CKR_OK)
 176     {
 177       gnutls_assert ();
 178       ret = pkcs11_rv_to_err (rv);
 179       goto cleanup;
 180     }
 181
 182   signature->data = gnutls_malloc (siglen);
 183   signature->size = siglen;
 184
 185   rv = pakchois_sign (pks, hash->data, hash->size, signature->data, &siglen);
 186   if (rv != CKR_OK)
 187     {
 188       gnutls_free (signature->data);
 189       gnutls_assert ();
 190       ret = pkcs11_rv_to_err (rv);
 191       goto cleanup;
 192     }
 193
 194   signature->size = siglen;
 195
 196   ret = 0;
 197
 198 cleanup:
 199   pakchois_close_session (pks);
 200
 201   return ret;
 202 }
 203
 204 /**
 205  * gnutls_pkcs11_privkey_import_url:
 206  * @pkey: The structure to store the parsed key
 207  * @url: a PKCS 11 url identifying the key
 208  * @flags: sequence of GNUTLS_PKCS_PRIVKEY_*
 209  *
 210  * This function will "import" a PKCS 11 URL identifying a private
 211  * key to the #gnutls_pkcs11_privkey_t structure. In reality since
 212  * in most cases keys cannot be exported, the private key structure
 213  * is being associated with the available operations on the token.
 214  *
 215  * Returns: On success, %GNUTLS_E_SUCCESS is returned, otherwise a
 216  *   negative error value.
 217  **/
 218 int
 219 gnutls_pkcs11_privkey_import_url (gnutls_pkcs11_privkey_t pkey,
 220                                   const char *url, unsigned int flags)
 221 {
 222   int ret;
 223
 224   ret = pkcs11_url_to_info (url, &pkey->info);
 225   if (ret < 0)
 226     {
 227       gnutls_assert ();
 228       return ret;
 229     }
 230
 231   pkey->flags = flags;
 232
 233   if (pkey->info.type[0] != 0 && strcmp (pkey->info.type, "private") != 0)
 234     {
 235       gnutls_assert ();
 236       return GNUTLS_E_INVALID_REQUEST;
 237     }
 238
 239   if (pkey->info.id[0] == 0)
 240     {
 241       gnutls_assert ();
 242       return GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE;
 243     }
 244
 245   return 0;
 246 }
 247
 248 /*-
 249  * _gnutls_pkcs11_privkey_decrypt_data:
 250  * @key: Holds the key
 251  * @flags: should be 0 for now
 252  * @ciphertext: holds the data to be signed
 253  * @plaintext: will contain the plaintext, allocated with gnutls_malloc()
 254  *
 255  * This function will decrypt the given data using the public key algorithm
 256  * supported by the private key.
 257  *
 258  * Returns: On success, %GNUTLS_E_SUCCESS is returned, otherwise a
 259  *   negative error value.
 260  -*/
 261 int
 262 _gnutls_pkcs11_privkey_decrypt_data (gnutls_pkcs11_privkey_t key,
 263                                     unsigned int flags,
 264                                     const gnutls_datum_t * ciphertext,
 265                                     gnutls_datum_t * plaintext)
 266 {
 267   ck_rv_t rv;
 268   int ret;
 269   struct ck_mechanism mech;
 270   unsigned long siglen;
 271   pakchois_session_t *pks;
 272   ck_object_handle_t obj;
 273
 274   FIND_OBJECT (pks, obj, key);
 275
 276   mech.mechanism =
 277     key->pk_algorithm == GNUTLS_PK_DSA ? CKM_DSA : CKM_RSA_PKCS;
 278   mech.parameter = NULL;
 279   mech.parameter_len = 0;
 280
 281   /* Initialize signing operation; using the private key discovered
 282    * earlier. */
 283   rv = pakchois_decrypt_init (pks, &mech, obj);
 284   if (rv != CKR_OK)
 285     {
 286       gnutls_assert ();
 287       ret = pkcs11_rv_to_err (rv);
 288       goto cleanup;
 289     }
 290
 291   /* Work out how long the plaintext must be: */
 292   rv = pakchois_decrypt (pks, ciphertext->data, ciphertext->size,
 293                          NULL, &siglen);
 294   if (rv != CKR_OK)
 295     {
 296       gnutls_assert ();
 297       ret = pkcs11_rv_to_err (rv);
 298       goto cleanup;
 299     }
 300
 301   plaintext->data = gnutls_malloc (siglen);
 302   plaintext->size = siglen;
 303
 304   rv = pakchois_decrypt (pks, ciphertext->data, ciphertext->size,
 305                          plaintext->data, &siglen);
 306   if (rv != CKR_OK)
 307     {
 308       gnutls_free (plaintext->data);
 309       gnutls_assert ();
 310       ret = pkcs11_rv_to_err (rv);
 311       goto cleanup;
 312     }
 313
 314   plaintext->size = siglen;
 315
 316   ret = 0;
 317
 318 cleanup:
 319   pakchois_close_session (pks);
 320
 321   return ret;
 322 }
 323
 324 /**
 325  * gnutls_pkcs11_privkey_export_url:
 326  * @key: Holds the PKCS 11 key
 327  * @detailed: non zero if a detailed URL is required
 328  * @url: will contain an allocated url
 329  *
 330  * This function will export a URL identifying the given key.
 331  *
 332  * Returns: On success, %GNUTLS_E_SUCCESS is returned, otherwise a
 333  *   negative error value.
 334  **/
 335 int
 336 gnutls_pkcs11_privkey_export_url (gnutls_pkcs11_privkey_t key,
 337                                   gnutls_pkcs11_url_type_t detailed,
 338                                   char **url)
 339 {
 340   int ret;
 341
 342   ret = pkcs11_info_to_url (&key->info, detailed, url);
 343   if (ret < 0)
 344     {
 345       gnutls_assert ();
 346       return ret;
 347     }
 348
 349   return 0;
 350 }