add srtp

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@1086 d0543943-73ff-0310-b7d9-9358b9ac24b2

libs/srtp/crypto/hash/auth.c

@@ -0,0 +1,173 @@
+/*
+ * auth.c
+ *
+ * some bookkeeping functions for authentication functions
+ *
+ * David A. McGrew
+ * Cisco Systems, Inc.
+ */
+
+/*
+ *	
+ * Copyright (c) 2001-2005, 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 "auth.h"
+
+/* the debug module for authentiation */
+
+debug_module_t mod_auth = {
+  0,                  /* debugging is off by default */
+  "auth func"         /* printable name for module   */
+};
+
+
+int
+auth_get_key_length(const auth_t *a) {
+  return a->key_len;
+}
+
+int
+auth_get_tag_length(const auth_t *a) {
+  return a->out_len;
+}
+
+int
+auth_get_prefix_length(const auth_t *a) {
+  return a->prefix_len;
+}
+
+int
+auth_type_get_ref_count(const auth_type_t *at) {
+  return at->ref_count;
+}
+
+/*
+ * auth_type_self_test() tests an auth function of type ct against
+ * test cases provided in an array of values of key, data, and tag
+ * that is known to be good
+ */
+
+/* should be big enough for most occasions */
+#define SELF_TEST_TAG_BUF_OCTETS 32
+
+err_status_t
+auth_type_self_test(const auth_type_t *at) {
+  auth_test_case_t *test_case = at->test_data;
+  auth_t *a;
+  err_status_t status;
+  uint8_t tag[SELF_TEST_TAG_BUF_OCTETS];
+  int i, case_num = 0;
+
+  debug_print(mod_auth, "running self-test for auth function %s", 
+	      at->description);
+  
+  /*
+   * check to make sure that we have at least one test case, and
+   * return an error if we don't - we need to be paranoid here
+   */
+  if (test_case == NULL)
+    return err_status_cant_check;
+
+  /* loop over all test cases */  
+  while (test_case != NULL) {
+
+    /* check test case parameters */
+    if (test_case->tag_length_octets > SELF_TEST_TAG_BUF_OCTETS)
+      return err_status_bad_param;
+    
+    /* allocate auth */
+    status = auth_type_alloc(at, &a, test_case->key_length_octets,
+			     test_case->tag_length_octets);
+    if (status)
+      return status;
+    
+    /* initialize auth */
+    status = auth_init(a, test_case->key);
+    if (status) {
+      auth_dealloc(a);
+      return status;
+    }
+
+    /* zeroize tag then compute */
+    octet_string_set_to_zero(tag, test_case->tag_length_octets);
+    status = auth_compute(a, test_case->data,
+			  test_case->data_length_octets, tag);
+    if (status) {
+      auth_dealloc(a);
+      return status;
+    }
+    
+    debug_print(mod_auth, "key: %s",
+		octet_string_hex_string(test_case->key,
+					test_case->key_length_octets));
+    debug_print(mod_auth, "data: %s",
+		octet_string_hex_string(test_case->data,
+				   test_case->data_length_octets));
+    debug_print(mod_auth, "tag computed: %s",
+	   octet_string_hex_string(tag, test_case->tag_length_octets));
+    debug_print(mod_auth, "tag expected: %s",
+	   octet_string_hex_string(test_case->tag,
+				   test_case->tag_length_octets));
+
+    /* check the result */
+    status = err_status_ok;
+    for (i=0; i < test_case->tag_length_octets; i++)
+      if (tag[i] != test_case->tag[i]) {
+	status = err_status_algo_fail;
+	debug_print(mod_auth, "test case %d failed", case_num);
+	debug_print(mod_auth, "  (mismatch at octet %d)", i);
+      }
+    if (status) {
+      auth_dealloc(a);
+      return err_status_algo_fail;
+    }
+    
+    /* deallocate the auth function */
+    status = auth_dealloc(a);
+    if (status)
+      return status;
+    
+    /* 
+     * the auth function passed the test case, so move on to the next test
+     * case in the list; if NULL, we'll quit and return an OK
+     */   
+    test_case = test_case->next_test_case;
+    ++case_num;
+  }
+  
+  return err_status_ok;
+}
+
+