The Tor Browser: netwerk/srtp/src/crypto/cipher/cipher.c@6474c204b198 (annotated)

netwerk/srtp/src/crypto/cipher/cipher.c@6474c204b198 (annotated)

netwerk/srtp/src/crypto/cipher/cipher.c

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /*
  * cipher.c
  *
  * cipher meta-functions
  *
  * 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 "cipher.h"
 #include "rand_source.h"        /* used in invertibiltiy tests        */
 #include "alloc.h"              /* for crypto_alloc(), crypto_free()  */
 debug_module_t mod_cipher = {
 ,                 /* debugging is off by default */
   "cipher"           /* printable module name       */
 };
 err_status_t
 cipher_output(cipher_t *c, uint8_t *buffer, int num_octets_to_output) {
   /* zeroize the buffer */
   octet_string_set_to_zero(buffer, num_octets_to_output);
   /* exor keystream into buffer */
   return cipher_encrypt(c, buffer, (unsigned int *) &num_octets_to_output);
 }
 /* some bookkeeping functions */
 int
 cipher_get_key_length(const cipher_t *c) {
   return c->key_len;
 }
 /*
  * 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
  */
 #define SELF_TEST_BUF_OCTETS 128
 #define NUM_RAND_TESTS       128
 #define MAX_KEY_LEN          64
 err_status_t
 cipher_type_test(const cipher_type_t *ct, const cipher_test_case_t *test_data) {
   const cipher_test_case_t *test_case = test_data;
   cipher_t *c;
   err_status_t status;
   uint8_t buffer[SELF_TEST_BUF_OCTETS];
   uint8_t buffer2[SELF_TEST_BUF_OCTETS];
   unsigned int len;
   int i, j, case_num = 0;
   debug_print(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 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 = cipher_type_alloc(ct, &c, test_case->key_length_octets);
     if (status)
       return status;
     /*
      * test the encrypt function
      */
     debug_print(mod_cipher, "testing encryption", NULL);
     /* initialize cipher */
     status = cipher_init(c, test_case->key, direction_encrypt);
     if (status) {
       cipher_dealloc(c);
       return status;
     }
     /* copy plaintext into test buffer */
     if (test_case->ciphertext_length_octets > SELF_TEST_BUF_OCTETS) {
       cipher_dealloc(c);
       return err_status_bad_param;
     }
     for (i=0; i < test_case->plaintext_length_octets; i++)
       buffer[i] = test_case->plaintext[i];
     debug_print(mod_cipher, "plaintext:    %s",
 	     octet_string_hex_string(buffer,
 				     test_case->plaintext_length_octets));
     /* set the initialization vector */
     status = cipher_set_iv(c, test_case->idx);
     if (status) {
       cipher_dealloc(c);
       return status;
     }
     /* encrypt */
     len = test_case->plaintext_length_octets;
     status = cipher_encrypt(c, buffer, &len);
     if (status) {
       cipher_dealloc(c);
       return status;
     }
     debug_print(mod_cipher, "ciphertext:   %s",
 	     octet_string_hex_string(buffer,
 				     test_case->ciphertext_length_octets));
     /* compare the resulting ciphertext with that in the test case */
     if (len != (unsigned int)test_case->ciphertext_length_octets)
       return err_status_algo_fail;
     status = err_status_ok;
     for (i=0; i < test_case->ciphertext_length_octets; i++)
       if (buffer[i] != test_case->ciphertext[i]) {
 	status = err_status_algo_fail;
 	debug_print(mod_cipher, "test case %d failed", case_num);
 	debug_print(mod_cipher, "(failure at byte %d)", i);
 	break;
       }
     if (status) {
       debug_print(mod_cipher, "c computed: %s",
 	     octet_string_hex_string(buffer,
 *test_case->plaintext_length_octets));
       debug_print(mod_cipher, "c expected: %s",
 		  octet_string_hex_string(test_case->ciphertext,
 *test_case->plaintext_length_octets));
       cipher_dealloc(c);
       return err_status_algo_fail;
     }
     /*
      * test the decrypt function
      */
     debug_print(mod_cipher, "testing decryption", NULL);
     /* re-initialize cipher for decryption */
     status = cipher_init(c, test_case->key, direction_decrypt);
     if (status) {
       cipher_dealloc(c);
       return status;
     }
     /* copy ciphertext into test buffer */
     if (test_case->ciphertext_length_octets > SELF_TEST_BUF_OCTETS) {
       cipher_dealloc(c);
       return err_status_bad_param;
     }
     for (i=0; i < test_case->ciphertext_length_octets; i++)
       buffer[i] = test_case->ciphertext[i];
     debug_print(mod_cipher, "ciphertext:    %s",
 		octet_string_hex_string(buffer,
 					test_case->plaintext_length_octets));
     /* set the initialization vector */
     status = cipher_set_iv(c, test_case->idx);
     if (status) {
       cipher_dealloc(c);
       return status;
     }
     /* decrypt */
     len = test_case->ciphertext_length_octets;
     status = cipher_decrypt(c, buffer, &len);
     if (status) {
       cipher_dealloc(c);
       return status;
     }
     debug_print(mod_cipher, "plaintext:   %s",
 	     octet_string_hex_string(buffer,
 				     test_case->plaintext_length_octets));
     /* compare the resulting plaintext with that in the test case */
     if (len != (unsigned int)test_case->plaintext_length_octets)
       return err_status_algo_fail;
     status = err_status_ok;
     for (i=0; i < test_case->plaintext_length_octets; i++)
       if (buffer[i] != test_case->plaintext[i]) {
 	status = err_status_algo_fail;
 	debug_print(mod_cipher, "test case %d failed", case_num);
 	debug_print(mod_cipher, "(failure at byte %d)", i);
       }
     if (status) {
       debug_print(mod_cipher, "p computed: %s",
 	     octet_string_hex_string(buffer,
 *test_case->plaintext_length_octets));
       debug_print(mod_cipher, "p expected: %s",
 		  octet_string_hex_string(test_case->plaintext,
 *test_case->plaintext_length_octets));
       cipher_dealloc(c);
       return err_status_algo_fail;
     }
     /* deallocate the cipher */
     status = 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 = cipher_type_alloc(ct, &c, test_case->key_length_octets);
   if (status)
       return status;
   rand_source_init();
   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(mod_cipher, "random plaintext length %d\n", length);
     status = rand_source_get_octet_string(buffer, length);
     if (status) return status;
     debug_print(mod_cipher, "plaintext:    %s",
 		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 err_status_cant_check;
     status = rand_source_get_octet_string(key, test_case->key_length_octets);
     if (status) return status;
    /* chose a random initialization vector */
     status = rand_source_get_octet_string(iv, MAX_KEY_LEN);
     if (status) return status;
     /* initialize cipher */
     status = cipher_init(c, key, direction_encrypt);
     if (status) {
       cipher_dealloc(c);
       return status;
     }
     /* set initialization vector */
     status = cipher_set_iv(c, test_case->idx);
     if (status) {
       cipher_dealloc(c);
       return status;
     }
     /* encrypt buffer with cipher */
     plaintext_len = length;
     status = cipher_encrypt(c, buffer, &length);
     if (status) {
       cipher_dealloc(c);
       return status;
     }
     debug_print(mod_cipher, "ciphertext:   %s",
 		octet_string_hex_string(buffer, length));
     /*
      * re-initialize cipher for decryption, re-set the iv, then
      * decrypt the ciphertext
      */
     status = cipher_init(c, key, direction_decrypt);
     if (status) {
       cipher_dealloc(c);
       return status;
     }
     status = cipher_set_iv(c, test_case->idx);
     if (status) {
       cipher_dealloc(c);
       return status;
     }
     status = cipher_decrypt(c, buffer, &length);
     if (status) {
       cipher_dealloc(c);
       return status;
     }
     debug_print(mod_cipher, "plaintext[2]: %s",
 		octet_string_hex_string(buffer, length));
     /* compare the resulting plaintext with the original one */
     if (length != (unsigned)plaintext_len)
       return err_status_algo_fail;
     status = err_status_ok;
     for (i=0; i < plaintext_len; i++)
       if (buffer[i] != buffer2[i]) {
 	status = err_status_algo_fail;
 	debug_print(mod_cipher, "random test case %d failed", case_num);
 	debug_print(mod_cipher, "(failure at byte %d)", i);
       }
     if (status) {
       cipher_dealloc(c);
       return err_status_algo_fail;
     }
   }
   status = cipher_dealloc(c);
   if (status)
     return status;
   return err_status_ok;
 }
 /*
  * cipher_type_self_test(ct) performs cipher_type_test on ct's internal
  * list of test data.
  */
 err_status_t
 cipher_type_self_test(const cipher_type_t *ct) {
   return 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
 cipher_bits_per_second(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*) 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) {
     cipher_set_iv(c, &nonce);
     cipher_encrypt(c, enc_buf, &len);
   }
   timer = clock() - timer;
   crypto_free(enc_buf);
   if (timer == 0) {
     /* Too fast! */
     return 0;
   }
   return (uint64_t)CLOCKS_PER_SEC * num_trials * 8 * octets_in_buffer / timer;
 }

The Tor Browser / annotate

netwerk/srtp/src/crypto/cipher/cipher.c@6474c204b198 (annotated)

netwerk/srtp/src/crypto/cipher/cipher.c