1 /* 2 * null_auth.c 3 * 4 * implements the do-nothing auth algorithm 5 * 6 * David A. McGrew 7 * Cisco Systems, Inc. 8 * 9 */ 10 11 /* 12 * 13 * Copyright (c) 2001-2006, Cisco Systems, Inc. 14 * All rights reserved. 15 * 16 * Redistribution and use in source and binary forms, with or without 17 * modification, are permitted provided that the following conditions 18 * are met: 19 * 20 * Redistributions of source code must retain the above copyright 21 * notice, this list of conditions and the following disclaimer. 22 * 23 * Redistributions in binary form must reproduce the above 24 * copyright notice, this list of conditions and the following 25 * disclaimer in the documentation and/or other materials provided 26 * with the distribution. 27 * 28 * Neither the name of the Cisco Systems, Inc. nor the names of its 29 * contributors may be used to endorse or promote products derived 30 * from this software without specific prior written permission. 31 * 32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 33 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 34 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 35 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 36 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 37 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 38 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 39 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 40 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 41 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 42 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 43 * OF THE POSSIBILITY OF SUCH DAMAGE. 44 * 45 */ 46 47 48 #include "null_auth.h" 49 #include "alloc.h" 50 51 /* null_auth uses the auth debug module */ 52 53 extern debug_module_t mod_auth; 54 55 err_status_t 56 null_auth_alloc(auth_t **a, int key_len, int out_len) { 57 extern auth_type_t null_auth; 58 uint8_t *pointer; 59 60 debug_print(mod_auth, "allocating auth func with key length %d", key_len); 61 debug_print(mod_auth, " tag length %d", out_len); 62 63 /* allocate memory for auth and null_auth_ctx_t structures */ 64 pointer = (uint8_t*)crypto_alloc(sizeof(null_auth_ctx_t) + sizeof(auth_t)); 65 if (pointer == NULL) 66 return err_status_alloc_fail; 67 68 /* set pointers */ 69 *a = (auth_t *)pointer; 70 (*a)->type = &null_auth; 71 (*a)->state = pointer + sizeof (auth_t); 72 (*a)->out_len = out_len; 73 (*a)->prefix_len = out_len; 74 (*a)->key_len = key_len; 75 76 /* increment global count of all null_auth uses */ 77 null_auth.ref_count++; 78 79 return err_status_ok; 80 } 81 82 err_status_t 83 null_auth_dealloc(auth_t *a) { 84 extern auth_type_t null_auth; 85 86 /* zeroize entire state*/ 87 octet_string_set_to_zero((uint8_t *)a, 88 sizeof(null_auth_ctx_t) + sizeof(auth_t)); 89 90 /* free memory */ 91 crypto_free(a); 92 93 /* decrement global count of all null_auth uses */ 94 null_auth.ref_count--; 95 96 return err_status_ok; 97 } 98 99 err_status_t 100 null_auth_init(null_auth_ctx_t *state, const uint8_t *key, int key_len) { 101 102 /* accept any length of key, and do nothing */ 103 104 return err_status_ok; 105 } 106 107 err_status_t 108 null_auth_compute(null_auth_ctx_t *state, uint8_t *message, 109 int msg_octets, int tag_len, uint8_t *result) { 110 111 return err_status_ok; 112 } 113 114 err_status_t 115 null_auth_update(null_auth_ctx_t *state, uint8_t *message, 116 int msg_octets) { 117 118 return err_status_ok; 119 } 120 121 err_status_t 122 null_auth_start(null_auth_ctx_t *state) { 123 return err_status_ok; 124 } 125 126 /* 127 * auth_type_t - defines description, test case, and null_auth 128 * metaobject 129 */ 130 131 /* begin test case 0 */ 132 133 auth_test_case_t 134 null_auth_test_case_0 = { 135 0, /* octets in key */ 136 NULL, /* key */ 137 0, /* octets in data */ 138 NULL, /* data */ 139 0, /* octets in tag */ 140 NULL, /* tag */ 141 NULL /* pointer to next testcase */ 142 }; 143 144 /* end test case 0 */ 145 146 char null_auth_description[] = "null authentication function"; 147 148 auth_type_t 149 null_auth = { 150 (auth_alloc_func) null_auth_alloc, 151 (auth_dealloc_func) null_auth_dealloc, 152 (auth_init_func) null_auth_init, 153 (auth_compute_func) null_auth_compute, 154 (auth_update_func) null_auth_update, 155 (auth_start_func) null_auth_start, 156 (char *) null_auth_description, 157 (int) 0, /* instance count */ 158 (auth_test_case_t *) &null_auth_test_case_0, 159 (debug_module_t *) NULL, 160 (auth_type_id_t) NULL_AUTH 161 }; 162 163
