| Index: crypto/cipher/cipher.c
|
| diff --git a/crypto/cipher/cipher.c b/crypto/cipher/cipher.c
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..a64337efd095297aba7dc43e6d8bbd3b732c9d00
|
| --- /dev/null
|
| +++ b/crypto/cipher/cipher.c
|
| @@ -0,0 +1,636 @@
|
| +/*
|
| + * cipher.c
|
| + *
|
| + * cipher meta-functions
|
| + *
|
| + * David A. McGrew
|
| + * Cisco Systems, Inc.
|
| + *
|
| + */
|
| +
|
| +/*
|
| + *
|
| + * Copyright (c) 2001-2006,2013 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.
|
| + *
|
| + */
|
| +
|
| +#ifdef HAVE_CONFIG_H
|
| + #include <config.h>
|
| +#endif
|
| +
|
| +#include "cipher.h"
|
| +#include "crypto_types.h"
|
| +#include "err.h" /* for srtp_debug */
|
| +#include "alloc.h" /* for crypto_alloc(), crypto_free() */
|
| +
|
| +srtp_debug_module_t srtp_mod_cipher = {
|
| + 0, /* debugging is off by default */
|
| + "cipher" /* printable module name */
|
| +};
|
| +
|
| +srtp_err_status_t srtp_cipher_type_alloc (const srtp_cipher_type_t *ct, srtp_cipher_t **c, int key_len, int tlen)
|
| +{
|
| + if (!ct || !ct->alloc) {
|
| + return (srtp_err_status_bad_param);
|
| + }
|
| + return ((ct)->alloc((c), (key_len), (tlen)));
|
| +}
|
| +
|
| +srtp_err_status_t srtp_cipher_dealloc (srtp_cipher_t *c)
|
| +{
|
| + if (!c || !c->type) {
|
| + return (srtp_err_status_bad_param);
|
| + }
|
| + return (((c)->type)->dealloc(c));
|
| +}
|
| +
|
| +srtp_err_status_t srtp_cipher_init (srtp_cipher_t *c, const uint8_t *key)
|
| +{
|
| + if (!c || !c->type || !c->state) {
|
| + return (srtp_err_status_bad_param);
|
| + }
|
| + return (((c)->type)->init(((c)->state), (key)));
|
| +}
|
| +
|
| +
|
| +srtp_err_status_t srtp_cipher_set_iv (srtp_cipher_t *c, uint8_t *iv, int direction)
|
| +{
|
| + if (!c || !c->type || !c->state) {
|
| + return (srtp_err_status_bad_param);
|
| + }
|
| +
|
| + return (((c)->type)->set_iv(((c)->state), iv, direction));
|
| +}
|
| +
|
| +srtp_err_status_t srtp_cipher_output (srtp_cipher_t *c, uint8_t *buffer, uint32_t *num_octets_to_output)
|
| +{
|
| +
|
| + /* zeroize the buffer */
|
| + octet_string_set_to_zero(buffer, *num_octets_to_output);
|
| +
|
| + /* exor keystream into buffer */
|
| + return (((c)->type)->encrypt(((c)->state), buffer, num_octets_to_output));
|
| +}
|
| +
|
| +srtp_err_status_t srtp_cipher_encrypt (srtp_cipher_t *c, uint8_t *buffer, uint32_t *num_octets_to_output)
|
| +{
|
| + if (!c || !c->type || !c->state) {
|
| + return (srtp_err_status_bad_param);
|
| + }
|
| +
|
| + return (((c)->type)->encrypt(((c)->state), buffer, num_octets_to_output));
|
| +}
|
| +
|
| +srtp_err_status_t srtp_cipher_decrypt (srtp_cipher_t *c, uint8_t *buffer, uint32_t *num_octets_to_output)
|
| +{
|
| + if (!c || !c->type || !c->state) {
|
| + return (srtp_err_status_bad_param);
|
| + }
|
| +
|
| + return (((c)->type)->decrypt(((c)->state), buffer, num_octets_to_output));
|
| +}
|
| +
|
| +srtp_err_status_t srtp_cipher_get_tag (srtp_cipher_t *c, uint8_t *buffer, uint32_t *tag_len)
|
| +{
|
| + if (!c || !c->type || !c->state) {
|
| + return (srtp_err_status_bad_param);
|
| + }
|
| + if (!((c)->type)->get_tag) {
|
| + return (srtp_err_status_no_such_op);
|
| + }
|
| +
|
| + return (((c)->type)->get_tag(((c)->state), buffer, tag_len));
|
| +}
|
| +
|
| +srtp_err_status_t srtp_cipher_set_aad (srtp_cipher_t *c, const uint8_t *aad, uint32_t aad_len)
|
| +{
|
| + if (!c || !c->type || !c->state) {
|
| + return (srtp_err_status_bad_param);
|
| + }
|
| + if (!((c)->type)->set_aad) {
|
| + return (srtp_err_status_no_such_op);
|
| + }
|
| +
|
| + return (((c)->type)->set_aad(((c)->state), aad, aad_len));
|
| +}
|
| +
|
| +/* some bookkeeping functions */
|
| +
|
| +int srtp_cipher_get_key_length (const srtp_cipher_t *c)
|
| +{
|
| + return c->key_len;
|
| +}
|
| +
|
| +
|
| +/*
|
| + * A trivial platform independent random source. The random
|
| + * data is used for some of the cipher self-tests.
|
| + */
|
| +static srtp_err_status_t srtp_cipher_rand (void *dest, uint32_t len)
|
| +{
|
| +#if defined(HAVE_RAND_S)
|
| + uint8_t *dst = (uint8_t *)dest;
|
| + while (len)
|
| + {
|
| + unsigned int val;
|
| + errno_t err = rand_s(&val);
|
| +
|
| + if (err != 0)
|
| + return srtp_err_status_fail;
|
| +
|
| + *dst++ = val & 0xff;
|
| + len--;
|
| + }
|
| +#else
|
| + /* Generic C-library (rand()) version */
|
| + /* This is a random source of last resort */
|
| + uint8_t *dst = (uint8_t *)dest;
|
| + while (len)
|
| + {
|
| + int val = rand();
|
| + /* rand() returns 0-32767 (ugh) */
|
| + /* Is this a good enough way to get random bytes?
|
| + It is if it passes FIPS-140... */
|
| + *dst++ = val & 0xff;
|
| + len--;
|
| + }
|
| +#endif
|
| + return srtp_err_status_ok;
|
| +}
|
| +
|
| +#define SELF_TEST_BUF_OCTETS 128
|
| +#define NUM_RAND_TESTS 128
|
| +#define MAX_KEY_LEN 64
|
| +/*
|
| + * srtp_cipher_type_test(ct, test_data) tests a cipher of type ct against
|
| + * test cases provided in a list test_data of values of key, salt, iv,
|
| + * plaintext, and ciphertext that is known to be good
|
| + */
|
| +srtp_err_status_t srtp_cipher_type_test (const srtp_cipher_type_t *ct, const srtp_cipher_test_case_t *test_data)
|
| +{
|
| + const srtp_cipher_test_case_t *test_case = test_data;
|
| + srtp_cipher_t *c;
|
| + srtp_err_status_t status;
|
| + uint8_t buffer[SELF_TEST_BUF_OCTETS];
|
| + uint8_t buffer2[SELF_TEST_BUF_OCTETS];
|
| + uint32_t tag_len;
|
| + unsigned int len;
|
| + int i, j, case_num = 0;
|
| +
|
| + debug_print(srtp_mod_cipher, "running self-test for cipher %s",
|
| + ct->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 srtp_err_status_cant_check;
|
| + }
|
| +
|
| + /*
|
| + * loop over all test cases, perform known-answer tests of both the
|
| + * encryption and decryption functions
|
| + */
|
| + while (test_case != NULL) {
|
| + /* allocate cipher */
|
| + status = srtp_cipher_type_alloc(ct, &c, test_case->key_length_octets, test_case->tag_length_octets);
|
| + if (status) {
|
| + return status;
|
| + }
|
| +
|
| + /*
|
| + * test the encrypt function
|
| + */
|
| + debug_print(srtp_mod_cipher, "testing encryption", NULL);
|
| +
|
| + /* initialize cipher */
|
| + status = srtp_cipher_init(c, test_case->key);
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return status;
|
| + }
|
| +
|
| + /* copy plaintext into test buffer */
|
| + if (test_case->ciphertext_length_octets > SELF_TEST_BUF_OCTETS) {
|
| + srtp_cipher_dealloc(c);
|
| + return srtp_err_status_bad_param;
|
| + }
|
| + for (i = 0; i < test_case->plaintext_length_octets; i++) {
|
| + buffer[i] = test_case->plaintext[i];
|
| + }
|
| +
|
| + debug_print(srtp_mod_cipher, "plaintext: %s",
|
| + srtp_octet_string_hex_string(buffer,
|
| + test_case->plaintext_length_octets));
|
| +
|
| + /* set the initialization vector */
|
| + status = srtp_cipher_set_iv(c, (uint8_t*)test_case->idx, srtp_direction_encrypt);
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return status;
|
| + }
|
| +
|
| + if (c->algorithm == SRTP_AES_128_GCM || c->algorithm == SRTP_AES_256_GCM) {
|
| + debug_print(srtp_mod_cipher, "IV: %s",
|
| + srtp_octet_string_hex_string(test_case->idx, 12));
|
| +
|
| + /*
|
| + * Set the AAD
|
| + */
|
| + status = srtp_cipher_set_aad(c, test_case->aad, test_case->aad_length_octets);
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return status;
|
| + }
|
| + debug_print(srtp_mod_cipher, "AAD: %s",
|
| + srtp_octet_string_hex_string(test_case->aad,
|
| + test_case->aad_length_octets));
|
| + }
|
| +
|
| + /* encrypt */
|
| + len = test_case->plaintext_length_octets;
|
| + status = srtp_cipher_encrypt(c, buffer, &len);
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return status;
|
| + }
|
| +
|
| + if (c->algorithm == SRTP_AES_128_GCM || c->algorithm == SRTP_AES_256_GCM) {
|
| + /*
|
| + * Get the GCM tag
|
| + */
|
| + status = srtp_cipher_get_tag(c, buffer + len, &tag_len);
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return status;
|
| + }
|
| + len += tag_len;
|
| + }
|
| +
|
| + debug_print(srtp_mod_cipher, "ciphertext: %s",
|
| + srtp_octet_string_hex_string(buffer,
|
| + test_case->ciphertext_length_octets));
|
| +
|
| + /* compare the resulting ciphertext with that in the test case */
|
| + if (len != test_case->ciphertext_length_octets) {
|
| + return srtp_err_status_algo_fail;
|
| + }
|
| + status = srtp_err_status_ok;
|
| + for (i = 0; i < test_case->ciphertext_length_octets; i++) {
|
| + if (buffer[i] != test_case->ciphertext[i]) {
|
| + status = srtp_err_status_algo_fail;
|
| + debug_print(srtp_mod_cipher, "test case %d failed", case_num);
|
| + debug_print(srtp_mod_cipher, "(failure at byte %d)", i);
|
| + break;
|
| + }
|
| + }
|
| + if (status) {
|
| +
|
| + debug_print(srtp_mod_cipher, "c computed: %s",
|
| + srtp_octet_string_hex_string(buffer,
|
| + 2 * test_case->plaintext_length_octets));
|
| + debug_print(srtp_mod_cipher, "c expected: %s",
|
| + srtp_octet_string_hex_string(test_case->ciphertext,
|
| + 2 * test_case->plaintext_length_octets));
|
| +
|
| + srtp_cipher_dealloc(c);
|
| + return srtp_err_status_algo_fail;
|
| + }
|
| +
|
| + /*
|
| + * test the decrypt function
|
| + */
|
| + debug_print(srtp_mod_cipher, "testing decryption", NULL);
|
| +
|
| + /* re-initialize cipher for decryption */
|
| + status = srtp_cipher_init(c, test_case->key);
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return status;
|
| + }
|
| +
|
| + /* copy ciphertext into test buffer */
|
| + if (test_case->ciphertext_length_octets > SELF_TEST_BUF_OCTETS) {
|
| + srtp_cipher_dealloc(c);
|
| + return srtp_err_status_bad_param;
|
| + }
|
| + for (i = 0; i < test_case->ciphertext_length_octets; i++) {
|
| + buffer[i] = test_case->ciphertext[i];
|
| + }
|
| +
|
| + debug_print(srtp_mod_cipher, "ciphertext: %s",
|
| + srtp_octet_string_hex_string(buffer,
|
| + test_case->plaintext_length_octets));
|
| +
|
| + /* set the initialization vector */
|
| + status = srtp_cipher_set_iv(c, (uint8_t*)test_case->idx, srtp_direction_decrypt);
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return status;
|
| + }
|
| +
|
| + if (c->algorithm == SRTP_AES_128_GCM || c->algorithm == SRTP_AES_256_GCM) {
|
| + /*
|
| + * Set the AAD
|
| + */
|
| + status = srtp_cipher_set_aad(c, test_case->aad, test_case->aad_length_octets);
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return status;
|
| + }
|
| + debug_print(srtp_mod_cipher, "AAD: %s",
|
| + srtp_octet_string_hex_string(test_case->aad,
|
| + test_case->aad_length_octets));
|
| + }
|
| +
|
| + /* decrypt */
|
| + len = test_case->ciphertext_length_octets;
|
| + status = srtp_cipher_decrypt(c, buffer, &len);
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return status;
|
| + }
|
| +
|
| + debug_print(srtp_mod_cipher, "plaintext: %s",
|
| + srtp_octet_string_hex_string(buffer,
|
| + test_case->plaintext_length_octets));
|
| +
|
| + /* compare the resulting plaintext with that in the test case */
|
| + if (len != test_case->plaintext_length_octets) {
|
| + return srtp_err_status_algo_fail;
|
| + }
|
| + status = srtp_err_status_ok;
|
| + for (i = 0; i < test_case->plaintext_length_octets; i++) {
|
| + if (buffer[i] != test_case->plaintext[i]) {
|
| + status = srtp_err_status_algo_fail;
|
| + debug_print(srtp_mod_cipher, "test case %d failed", case_num);
|
| + debug_print(srtp_mod_cipher, "(failure at byte %d)", i);
|
| + }
|
| + }
|
| + if (status) {
|
| +
|
| + debug_print(srtp_mod_cipher, "p computed: %s",
|
| + srtp_octet_string_hex_string(buffer,
|
| + 2 * test_case->plaintext_length_octets));
|
| + debug_print(srtp_mod_cipher, "p expected: %s",
|
| + srtp_octet_string_hex_string(test_case->plaintext,
|
| + 2 * test_case->plaintext_length_octets));
|
| +
|
| + srtp_cipher_dealloc(c);
|
| + return srtp_err_status_algo_fail;
|
| + }
|
| +
|
| + /* deallocate the cipher */
|
| + status = srtp_cipher_dealloc(c);
|
| + if (status) {
|
| + return status;
|
| + }
|
| +
|
| + /*
|
| + * the cipher passed the test case, so move on to the next test
|
| + * case in the list; if NULL, we'l proceed to the next test
|
| + */
|
| + test_case = test_case->next_test_case;
|
| + ++case_num;
|
| + }
|
| +
|
| + /* now run some random invertibility tests */
|
| +
|
| + /* allocate cipher, using paramaters from the first test case */
|
| + test_case = test_data;
|
| + status = srtp_cipher_type_alloc(ct, &c, test_case->key_length_octets, test_case->tag_length_octets);
|
| + if (status) {
|
| + return status;
|
| + }
|
| +
|
| + for (j = 0; j < NUM_RAND_TESTS; j++) {
|
| + unsigned length;
|
| + int plaintext_len;
|
| + uint8_t key[MAX_KEY_LEN];
|
| + uint8_t iv[MAX_KEY_LEN];
|
| +
|
| + /* choose a length at random (leaving room for IV and padding) */
|
| + length = rand() % (SELF_TEST_BUF_OCTETS - 64);
|
| + debug_print(srtp_mod_cipher, "random plaintext length %d\n", length);
|
| + status = srtp_cipher_rand(buffer, length);
|
| + if (status) {
|
| + return status;
|
| + }
|
| +
|
| + debug_print(srtp_mod_cipher, "plaintext: %s",
|
| + srtp_octet_string_hex_string(buffer, length));
|
| +
|
| + /* copy plaintext into second buffer */
|
| + for (i = 0; (unsigned int)i < length; i++) {
|
| + buffer2[i] = buffer[i];
|
| + }
|
| +
|
| + /* choose a key at random */
|
| + if (test_case->key_length_octets > MAX_KEY_LEN) {
|
| + return srtp_err_status_cant_check;
|
| + }
|
| + status = srtp_cipher_rand(key, test_case->key_length_octets);
|
| + if (status) {
|
| + return status;
|
| + }
|
| +
|
| + /* chose a random initialization vector */
|
| + status = srtp_cipher_rand(iv, MAX_KEY_LEN);
|
| + if (status) {
|
| + return status;
|
| + }
|
| +
|
| + /* initialize cipher */
|
| + status = srtp_cipher_init(c, key);
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return status;
|
| + }
|
| +
|
| + /* set initialization vector */
|
| + status = srtp_cipher_set_iv(c, (uint8_t*)test_case->idx, srtp_direction_encrypt);
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return status;
|
| + }
|
| +
|
| + if (c->algorithm == SRTP_AES_128_GCM || c->algorithm == SRTP_AES_256_GCM) {
|
| + /*
|
| + * Set the AAD
|
| + */
|
| + status = srtp_cipher_set_aad(c, test_case->aad, test_case->aad_length_octets);
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return status;
|
| + }
|
| + debug_print(srtp_mod_cipher, "AAD: %s",
|
| + srtp_octet_string_hex_string(test_case->aad,
|
| + test_case->aad_length_octets));
|
| + }
|
| +
|
| + /* encrypt buffer with cipher */
|
| + plaintext_len = length;
|
| + status = srtp_cipher_encrypt(c, buffer, &length);
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return status;
|
| + }
|
| + if (c->algorithm == SRTP_AES_128_GCM || c->algorithm == SRTP_AES_256_GCM) {
|
| + /*
|
| + * Get the GCM tag
|
| + */
|
| + status = srtp_cipher_get_tag(c, buffer + length, &tag_len);
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return status;
|
| + }
|
| + length += tag_len;
|
| + }
|
| + debug_print(srtp_mod_cipher, "ciphertext: %s",
|
| + srtp_octet_string_hex_string(buffer, length));
|
| +
|
| + /*
|
| + * re-initialize cipher for decryption, re-set the iv, then
|
| + * decrypt the ciphertext
|
| + */
|
| + status = srtp_cipher_init(c, key);
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return status;
|
| + }
|
| + status = srtp_cipher_set_iv(c, (uint8_t*)test_case->idx, srtp_direction_decrypt);
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return status;
|
| + }
|
| + if (c->algorithm == SRTP_AES_128_GCM || c->algorithm == SRTP_AES_256_GCM) {
|
| + /*
|
| + * Set the AAD
|
| + */
|
| + status = srtp_cipher_set_aad(c, test_case->aad, test_case->aad_length_octets);
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return status;
|
| + }
|
| + debug_print(srtp_mod_cipher, "AAD: %s",
|
| + srtp_octet_string_hex_string(test_case->aad,
|
| + test_case->aad_length_octets));
|
| + }
|
| + status = srtp_cipher_decrypt(c, buffer, &length);
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return status;
|
| + }
|
| +
|
| + debug_print(srtp_mod_cipher, "plaintext[2]: %s",
|
| + srtp_octet_string_hex_string(buffer, length));
|
| +
|
| + /* compare the resulting plaintext with the original one */
|
| + if (length != plaintext_len) {
|
| + return srtp_err_status_algo_fail;
|
| + }
|
| + status = srtp_err_status_ok;
|
| + for (i = 0; i < plaintext_len; i++) {
|
| + if (buffer[i] != buffer2[i]) {
|
| + status = srtp_err_status_algo_fail;
|
| + debug_print(srtp_mod_cipher, "random test case %d failed", case_num);
|
| + debug_print(srtp_mod_cipher, "(failure at byte %d)", i);
|
| + }
|
| + }
|
| + if (status) {
|
| + srtp_cipher_dealloc(c);
|
| + return srtp_err_status_algo_fail;
|
| + }
|
| +
|
| + }
|
| +
|
| + status = srtp_cipher_dealloc(c);
|
| + if (status) {
|
| + return status;
|
| + }
|
| +
|
| + return srtp_err_status_ok;
|
| +}
|
| +
|
| +
|
| +/*
|
| + * srtp_cipher_type_self_test(ct) performs srtp_cipher_type_test on ct's internal
|
| + * list of test data.
|
| + */
|
| +srtp_err_status_t srtp_cipher_type_self_test (const srtp_cipher_type_t *ct)
|
| +{
|
| + return srtp_cipher_type_test(ct, ct->test_data);
|
| +}
|
| +
|
| +/*
|
| + * cipher_bits_per_second(c, l, t) computes (an estimate of) the
|
| + * number of bits that a cipher implementation can encrypt in a second
|
| + *
|
| + * c is a cipher (which MUST be allocated and initialized already), l
|
| + * is the length in octets of the test data to be encrypted, and t is
|
| + * the number of trials
|
| + *
|
| + * if an error is encountered, the value 0 is returned
|
| + */
|
| +uint64_t srtp_cipher_bits_per_second (srtp_cipher_t *c, int octets_in_buffer, int num_trials)
|
| +{
|
| + int i;
|
| + v128_t nonce;
|
| + clock_t timer;
|
| + unsigned char *enc_buf;
|
| + unsigned int len = octets_in_buffer;
|
| +
|
| + enc_buf = (unsigned char*)srtp_crypto_alloc(octets_in_buffer);
|
| + if (enc_buf == NULL) {
|
| + return 0; /* indicate bad parameters by returning null */
|
| +
|
| + }
|
| + /* time repeated trials */
|
| + v128_set_to_zero(&nonce);
|
| + timer = clock();
|
| + for (i = 0; i < num_trials; i++, nonce.v32[3] = i) {
|
| + srtp_cipher_set_iv(c, (uint8_t*)&nonce, srtp_direction_encrypt);
|
| + srtp_cipher_encrypt(c, enc_buf, &len);
|
| + }
|
| + timer = clock() - timer;
|
| +
|
| + srtp_crypto_free(enc_buf);
|
| +
|
| + if (timer == 0) {
|
| + /* Too fast! */
|
| + return 0;
|
| + }
|
| +
|
| + return (uint64_t)CLOCKS_PER_SEC * num_trials * 8 * octets_in_buffer / timer;
|
| +}
|
|
|