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Diffstat (limited to 'srtp/crypto/hash/null_auth.c')
| -rw-r--r-- | srtp/crypto/hash/null_auth.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/srtp/crypto/hash/null_auth.c b/srtp/crypto/hash/null_auth.c new file mode 100644 index 0000000..301348b --- /dev/null +++ b/srtp/crypto/hash/null_auth.c @@ -0,0 +1,160 @@ +/* + * 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 +}; + |