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.

     1 /*
     2  * cipher.c
     3  *
     4  * cipher meta-functions
     5  *
     6  * David A. McGrew
     7  * Cisco Systems, Inc.
     8  * 
     9  */
    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  */
    47 #include "cipher.h"
    48 #include "rand_source.h"        /* used in invertibiltiy tests        */
    49 #include "alloc.h"              /* for crypto_alloc(), crypto_free()  */
    51 debug_module_t mod_cipher = {
    52   0,                 /* debugging is off by default */
    53   "cipher"           /* printable module name       */
    54 };
    56 err_status_t
    57 cipher_output(cipher_t *c, uint8_t *buffer, int num_octets_to_output) {
    59   /* zeroize the buffer */
    60   octet_string_set_to_zero(buffer, num_octets_to_output);
    62   /* exor keystream into buffer */
    63   return cipher_encrypt(c, buffer, (unsigned int *) &num_octets_to_output);
    64 }
    66 /* some bookkeeping functions */
    68 int
    69 cipher_get_key_length(const cipher_t *c) {
    70   return c->key_len;
    71 }
    73 /* 
    74  * cipher_type_test(ct, test_data) tests a cipher of type ct against
    75  * test cases provided in a list test_data of values of key, salt, iv,
    76  * plaintext, and ciphertext that is known to be good
    77  */
    79 #define SELF_TEST_BUF_OCTETS 128
    80 #define NUM_RAND_TESTS       128
    81 #define MAX_KEY_LEN          64
    83 err_status_t
    84 cipher_type_test(const cipher_type_t *ct, const cipher_test_case_t *test_data) {
    85   const cipher_test_case_t *test_case = test_data;
    86   cipher_t *c;
    87   err_status_t status;
    88   uint8_t buffer[SELF_TEST_BUF_OCTETS];
    89   uint8_t buffer2[SELF_TEST_BUF_OCTETS];
    90   unsigned int len;
    91   int i, j, case_num = 0;
    93   debug_print(mod_cipher, "running self-test for cipher %s", 
    94 	      ct->description);
    96   /*
    97    * check to make sure that we have at least one test case, and
    98    * return an error if we don't - we need to be paranoid here
    99    */
   100   if (test_case == NULL)
   101     return err_status_cant_check;
   103   /*
   104    * loop over all test cases, perform known-answer tests of both the
   105    * encryption and decryption functions
   106    */  
   107   while (test_case != NULL) {
   109     /* allocate cipher */
   110     status = cipher_type_alloc(ct, &c, test_case->key_length_octets);
   111     if (status)
   112       return status;
   114     /*
   115      * test the encrypt function 
   116      */
   117     debug_print(mod_cipher, "testing encryption", NULL);    
   119     /* initialize cipher */
   120     status = cipher_init(c, test_case->key, direction_encrypt);
   121     if (status) {
   122       cipher_dealloc(c);
   123       return status;
   124     }
   126     /* copy plaintext into test buffer */
   127     if (test_case->ciphertext_length_octets > SELF_TEST_BUF_OCTETS) {
   128       cipher_dealloc(c);    
   129       return err_status_bad_param;
   130     }
   131     for (i=0; i < test_case->plaintext_length_octets; i++)
   132       buffer[i] = test_case->plaintext[i];
   134     debug_print(mod_cipher, "plaintext:    %s",
   135 	     octet_string_hex_string(buffer,
   136 				     test_case->plaintext_length_octets));
   138     /* set the initialization vector */
   139     status = cipher_set_iv(c, test_case->idx);
   140     if (status) {
   141       cipher_dealloc(c);
   142       return status;
   143     } 
   145     /* encrypt */
   146     len = test_case->plaintext_length_octets;
   147     status = cipher_encrypt(c, buffer, &len);
   148     if (status) {
   149       cipher_dealloc(c);
   150       return status;
   151     }
   153     debug_print(mod_cipher, "ciphertext:   %s",
   154 	     octet_string_hex_string(buffer,
   155 				     test_case->ciphertext_length_octets));
   157     /* compare the resulting ciphertext with that in the test case */
   158     if (len != (unsigned int)test_case->ciphertext_length_octets)
   159       return err_status_algo_fail;
   160     status = err_status_ok;
   161     for (i=0; i < test_case->ciphertext_length_octets; i++)
   162       if (buffer[i] != test_case->ciphertext[i]) {
   163 	status = err_status_algo_fail;
   164 	debug_print(mod_cipher, "test case %d failed", case_num);
   165 	debug_print(mod_cipher, "(failure at byte %d)", i);
   166 	break;
   167       }
   168     if (status) {
   170       debug_print(mod_cipher, "c computed: %s",
   171 	     octet_string_hex_string(buffer,
   172 		  2*test_case->plaintext_length_octets));
   173       debug_print(mod_cipher, "c expected: %s",
   174 		  octet_string_hex_string(test_case->ciphertext,
   175 			  2*test_case->plaintext_length_octets));
   177       cipher_dealloc(c);
   178       return err_status_algo_fail;
   179     }
   181     /*
   182      * test the decrypt function
   183      */
   184     debug_print(mod_cipher, "testing decryption", NULL);    
   186     /* re-initialize cipher for decryption */
   187     status = cipher_init(c, test_case->key, direction_decrypt);
   188     if (status) {
   189       cipher_dealloc(c);
   190       return status;
   191     }
   193     /* copy ciphertext into test buffer */
   194     if (test_case->ciphertext_length_octets > SELF_TEST_BUF_OCTETS) {
   195       cipher_dealloc(c);    
   196       return err_status_bad_param;
   197     }
   198     for (i=0; i < test_case->ciphertext_length_octets; i++)
   199       buffer[i] = test_case->ciphertext[i];
   201     debug_print(mod_cipher, "ciphertext:    %s",
   202 		octet_string_hex_string(buffer,
   203 					test_case->plaintext_length_octets));
   205     /* set the initialization vector */
   206     status = cipher_set_iv(c, test_case->idx);
   207     if (status) {
   208       cipher_dealloc(c);
   209       return status;
   210     } 
   212     /* decrypt */
   213     len = test_case->ciphertext_length_octets;
   214     status = cipher_decrypt(c, buffer, &len);
   215     if (status) {
   216       cipher_dealloc(c);
   217       return status;
   218     }
   220     debug_print(mod_cipher, "plaintext:   %s",
   221 	     octet_string_hex_string(buffer,
   222 				     test_case->plaintext_length_octets));
   224     /* compare the resulting plaintext with that in the test case */
   225     if (len != (unsigned int)test_case->plaintext_length_octets)
   226       return err_status_algo_fail;
   227     status = err_status_ok;
   228     for (i=0; i < test_case->plaintext_length_octets; i++)
   229       if (buffer[i] != test_case->plaintext[i]) {
   230 	status = err_status_algo_fail;
   231 	debug_print(mod_cipher, "test case %d failed", case_num);
   232 	debug_print(mod_cipher, "(failure at byte %d)", i);
   233       }
   234     if (status) {
   236       debug_print(mod_cipher, "p computed: %s",
   237 	     octet_string_hex_string(buffer,
   238 		  2*test_case->plaintext_length_octets));
   239       debug_print(mod_cipher, "p expected: %s",
   240 		  octet_string_hex_string(test_case->plaintext,
   241 			  2*test_case->plaintext_length_octets));
   243       cipher_dealloc(c);
   244       return err_status_algo_fail;
   245     }
   247     /* deallocate the cipher */
   248     status = cipher_dealloc(c);
   249     if (status)
   250       return status;
   252     /* 
   253      * the cipher passed the test case, so move on to the next test
   254      * case in the list; if NULL, we'l proceed to the next test
   255      */   
   256     test_case = test_case->next_test_case;
   257     ++case_num;
   258   }
   260   /* now run some random invertibility tests */
   262   /* allocate cipher, using paramaters from the first test case */
   263   test_case = test_data;
   264   status = cipher_type_alloc(ct, &c, test_case->key_length_octets);
   265   if (status)
   266       return status;
   268   rand_source_init();
   270   for (j=0; j < NUM_RAND_TESTS; j++) {
   271     unsigned length;
   272     int plaintext_len;
   273     uint8_t key[MAX_KEY_LEN];
   274     uint8_t  iv[MAX_KEY_LEN];
   276     /* choose a length at random (leaving room for IV and padding) */
   277     length = rand() % (SELF_TEST_BUF_OCTETS - 64);
   278     debug_print(mod_cipher, "random plaintext length %d\n", length);
   279     status = rand_source_get_octet_string(buffer, length);
   280     if (status) return status;
   282     debug_print(mod_cipher, "plaintext:    %s",
   283 		octet_string_hex_string(buffer, length));
   285     /* copy plaintext into second buffer */
   286     for (i=0; (unsigned int)i < length; i++)
   287       buffer2[i] = buffer[i];
   289     /* choose a key at random */
   290     if (test_case->key_length_octets > MAX_KEY_LEN)
   291       return err_status_cant_check;
   292     status = rand_source_get_octet_string(key, test_case->key_length_octets);
   293     if (status) return status;
   295    /* chose a random initialization vector */
   296     status = rand_source_get_octet_string(iv, MAX_KEY_LEN);
   297     if (status) return status;
   299     /* initialize cipher */
   300     status = cipher_init(c, key, direction_encrypt);
   301     if (status) {
   302       cipher_dealloc(c);
   303       return status;
   304     }
   306     /* set initialization vector */
   307     status = cipher_set_iv(c, test_case->idx);
   308     if (status) {
   309       cipher_dealloc(c);
   310       return status;
   311     } 
   313     /* encrypt buffer with cipher */
   314     plaintext_len = length;
   315     status = cipher_encrypt(c, buffer, &length);
   316     if (status) {
   317       cipher_dealloc(c);
   318       return status;
   319     }
   320     debug_print(mod_cipher, "ciphertext:   %s",
   321 		octet_string_hex_string(buffer, length));
   323     /* 
   324      * re-initialize cipher for decryption, re-set the iv, then
   325      * decrypt the ciphertext
   326      */
   327     status = cipher_init(c, key, direction_decrypt);
   328     if (status) {
   329       cipher_dealloc(c);
   330       return status;
   331     }
   332     status = cipher_set_iv(c, test_case->idx);
   333     if (status) {
   334       cipher_dealloc(c);
   335       return status;
   336     } 
   337     status = cipher_decrypt(c, buffer, &length);
   338     if (status) {
   339       cipher_dealloc(c);
   340       return status;
   341     }    
   343     debug_print(mod_cipher, "plaintext[2]: %s",
   344 		octet_string_hex_string(buffer, length));    
   346     /* compare the resulting plaintext with the original one */
   347     if (length != (unsigned)plaintext_len)
   348       return err_status_algo_fail;
   349     status = err_status_ok;
   350     for (i=0; i < plaintext_len; i++)
   351       if (buffer[i] != buffer2[i]) {
   352 	status = err_status_algo_fail;
   353 	debug_print(mod_cipher, "random test case %d failed", case_num);
   354 	debug_print(mod_cipher, "(failure at byte %d)", i);
   355       }
   356     if (status) {
   357       cipher_dealloc(c);
   358       return err_status_algo_fail;
   359     }
   361   }
   363   status = cipher_dealloc(c);
   364   if (status)
   365     return status;
   367   return err_status_ok;
   368 }
   371 /* 
   372  * cipher_type_self_test(ct) performs cipher_type_test on ct's internal
   373  * list of test data.
   374  */
   376 err_status_t
   377 cipher_type_self_test(const cipher_type_t *ct) {
   378   return cipher_type_test(ct, ct->test_data);
   379 }
   381 /*
   382  * cipher_bits_per_second(c, l, t) computes (an estimate of) the
   383  * number of bits that a cipher implementation can encrypt in a second
   384  * 
   385  * c is a cipher (which MUST be allocated and initialized already), l
   386  * is the length in octets of the test data to be encrypted, and t is
   387  * the number of trials
   388  *
   389  * if an error is encountered, the value 0 is returned
   390  */
   392 uint64_t
   393 cipher_bits_per_second(cipher_t *c, int octets_in_buffer, int num_trials) {
   394   int i;
   395   v128_t nonce;
   396   clock_t timer;
   397   unsigned char *enc_buf;
   398   unsigned int len = octets_in_buffer;
   400   enc_buf = (unsigned char*) crypto_alloc(octets_in_buffer);
   401   if (enc_buf == NULL)
   402     return 0;  /* indicate bad parameters by returning null */
   404   /* time repeated trials */
   405   v128_set_to_zero(&nonce);
   406   timer = clock();
   407   for(i=0; i < num_trials; i++, nonce.v32[3] = i) {
   408     cipher_set_iv(c, &nonce);
   409     cipher_encrypt(c, enc_buf, &len);
   410   }
   411   timer = clock() - timer;
   413   crypto_free(enc_buf);
   415   if (timer == 0) {
   416     /* Too fast! */
   417     return 0;
   418   }
   420   return (uint64_t)CLOCKS_PER_SEC * num_trials * 8 * octets_in_buffer / timer;
   421 }

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