Add current version of libSRTP from CVS.

libsrtp/crypto/hash/null_auth.c

+/*
+ * null_auth.c
+ *
+ * implements the do-nothing auth algorithm
+ *
+ * David A. McGrew
+ * Cisco Systems, Inc.
+ *
+ */
+
+/*
+ *      
+ * Copyright (c) 2001-2006, Cisco Systems, Inc.
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 
+ *   Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials provided
+ *   with the distribution.
+ * 
+ *   Neither the name of the Cisco Systems, Inc. nor the names of its
+ *   contributors may be used to endorse or promote products derived
+ *   from this software without specific prior written permission.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+
+#include "null_auth.h" 
+#include "alloc.h"
+
+/* null_auth uses the auth debug module */
+
+extern debug_module_t mod_auth;
+
+err_status_t
+null_auth_alloc(auth_t **a, int key_len, int out_len) {
+  extern auth_type_t null_auth;
+  uint8_t *pointer;
+
+  debug_print(mod_auth, "allocating auth func with key length %d", key_len);
+  debug_print(mod_auth, "                          tag length %d", out_len);
+
+  /* allocate memory for auth and null_auth_ctx_t structures */
+  pointer = (uint8_t*)crypto_alloc(sizeof(null_auth_ctx_t) + sizeof(auth_t));
+  if (pointer == NULL)
+    return err_status_alloc_fail;
+
+  /* set pointers */
+  *a = (auth_t *)pointer;
+  (*a)->type = &null_auth;
+  (*a)->state = pointer + sizeof (auth_t);  
+  (*a)->out_len = out_len;
+  (*a)->prefix_len = out_len;
+  (*a)->key_len = key_len;
+
+  /* increment global count of all null_auth uses */
+  null_auth.ref_count++;
+
+  return err_status_ok;
+}
+
+err_status_t
+null_auth_dealloc(auth_t *a) {
+  extern auth_type_t null_auth;
+  
+  /* zeroize entire state*/
+  octet_string_set_to_zero((uint8_t *)a, 
+                           sizeof(null_auth_ctx_t) + sizeof(auth_t));
+
+  /* free memory */
+  crypto_free(a);
+  
+  /* decrement global count of all null_auth uses */
+  null_auth.ref_count--;
+
+  return err_status_ok;
+}
+
+err_status_t
+null_auth_init(null_auth_ctx_t *state, const uint8_t *key, int key_len) {
+
+  /* accept any length of key, and do nothing */
+  
+  return err_status_ok;
+}
+
+err_status_t
+null_auth_compute(null_auth_ctx_t *state, uint8_t *message,
+                   int msg_octets, int tag_len, uint8_t *result) {
+
+  return err_status_ok;
+}
+
+err_status_t
+null_auth_update(null_auth_ctx_t *state, uint8_t *message,
+                   int msg_octets) {
+
+  return err_status_ok;
+}
+
+err_status_t
+null_auth_start(null_auth_ctx_t *state) {
+  return err_status_ok;
+}
+
+/*
+ * auth_type_t - defines description, test case, and null_auth
+ * metaobject
+ */
+
+/* begin test case 0 */
+
+auth_test_case_t
+null_auth_test_case_0 = {
+  0,                                       /* octets in key            */
+  NULL,                                    /* key                      */
+  0,                                       /* octets in data           */ 
+  NULL,                                    /* data                     */
+  0,                                       /* octets in tag            */
+  NULL,                                    /* tag                      */
+  NULL                                     /* pointer to next testcase */
+};
+
+/* end test case 0 */
+
+char null_auth_description[] = "null authentication function";
+
+auth_type_t
+null_auth  = {
+  (auth_alloc_func)      null_auth_alloc,
+  (auth_dealloc_func)    null_auth_dealloc,
+  (auth_init_func)       null_auth_init,
+  (auth_compute_func)    null_auth_compute,
+  (auth_update_func)     null_auth_update,
+  (auth_start_func)      null_auth_start,
+  (char *)               null_auth_description,
+  (int)                  0,  /* instance count */
+  (auth_test_case_t *)   &null_auth_test_case_0,
+  (debug_module_t *)     NULL,
+  (auth_type_id_t)       NULL_AUTH
+};
+