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-rw-r--r--third_party/libsrtp/src/crypto/cipher/cipher.c664
1 files changed, 664 insertions, 0 deletions
diff --git a/third_party/libsrtp/src/crypto/cipher/cipher.c b/third_party/libsrtp/src/crypto/cipher/cipher.c
new file mode 100644
index 0000000000..de93bc90d8
--- /dev/null
+++ b/third_party/libsrtp/src/crypto/cipher/cipher.c
@@ -0,0 +1,664 @@
+/*
+ * cipher.c
+ *
+ * cipher meta-functions
+ *
+ * David A. McGrew
+ * Cisco Systems, Inc.
+ *
+ */
+
+/*
+ *
+ * Copyright (c) 2001-2017 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 "cipher_priv.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.
+ * For use in test only.
+ */
+void srtp_cipher_rand_for_tests(void *dest, uint32_t len)
+{
+ /* 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--;
+ }
+}
+
+/*
+ * A trivial platform independent 32 bit random number.
+ * For use in test only.
+ */
+uint32_t srtp_cipher_rand_u32_for_tests(void)
+{
+ uint32_t r;
+ srtp_cipher_rand_for_tests(&r, sizeof(r));
+ return r;
+}
+
+#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;
+ unsigned k = 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_print0(srtp_mod_cipher, "testing encryption");
+
+ /* 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 (k = 0; k < test_case->plaintext_length_octets; k++) {
+ buffer[k] = test_case->plaintext[k];
+ }
+
+ 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_GCM_128 ||
+ c->algorithm == SRTP_AES_GCM_256) {
+ 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_GCM_128 ||
+ c->algorithm == SRTP_AES_GCM_256) {
+ /*
+ * 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) {
+ srtp_cipher_dealloc(c);
+ return srtp_err_status_algo_fail;
+ }
+ status = srtp_err_status_ok;
+ for (k = 0; k < test_case->ciphertext_length_octets; k++) {
+ if (buffer[k] != test_case->ciphertext[k]) {
+ 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 %u)", k);
+ 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_print0(srtp_mod_cipher, "testing decryption");
+
+ /* 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 (k = 0; k < test_case->ciphertext_length_octets; k++) {
+ buffer[k] = test_case->ciphertext[k];
+ }
+
+ 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_GCM_128 ||
+ c->algorithm == SRTP_AES_GCM_256) {
+ /*
+ * 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) {
+ srtp_cipher_dealloc(c);
+ return srtp_err_status_algo_fail;
+ }
+ status = srtp_err_status_ok;
+ for (k = 0; k < test_case->plaintext_length_octets; k++) {
+ if (buffer[k] != test_case->plaintext[k]) {
+ 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 %u)", k);
+ }
+ }
+ 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 int length;
+ unsigned 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 = srtp_cipher_rand_u32_for_tests() % (SELF_TEST_BUF_OCTETS - 64);
+ debug_print(srtp_mod_cipher, "random plaintext length %d\n", length);
+ srtp_cipher_rand_for_tests(buffer, length);
+
+ 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) {
+ srtp_cipher_dealloc(c);
+ return srtp_err_status_cant_check;
+ }
+ srtp_cipher_rand_for_tests(key, test_case->key_length_octets);
+
+ /* chose a random initialization vector */
+ srtp_cipher_rand_for_tests(iv, MAX_KEY_LEN);
+
+ /* 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_GCM_128 ||
+ c->algorithm == SRTP_AES_GCM_256) {
+ /*
+ * 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_GCM_128 ||
+ c->algorithm == SRTP_AES_GCM_256) {
+ /*
+ * 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_GCM_128 ||
+ c->algorithm == SRTP_AES_GCM_256) {
+ /*
+ * 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) {
+ srtp_cipher_dealloc(c);
+ return srtp_err_status_algo_fail;
+ }
+ status = srtp_err_status_ok;
+ for (k = 0; k < plaintext_len; k++) {
+ if (buffer[k] != buffer2[k]) {
+ 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 %u)", k);
+ }
+ }
+ 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) {
+ if (srtp_cipher_set_iv(c, (uint8_t *)&nonce, srtp_direction_encrypt) !=
+ srtp_err_status_ok) {
+ srtp_crypto_free(enc_buf);
+ return 0;
+ }
+ if (srtp_cipher_encrypt(c, enc_buf, &len) != srtp_err_status_ok) {
+ srtp_crypto_free(enc_buf);
+ return 0;
+ }
+ }
+ 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;
+}
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