Commit 3647751c authored by Nick Mathewson's avatar Nick Mathewson 🤹
Browse files

prop140: Use sha3-256, not sha2-256 

This is a protocol update from recent prop140 changes.

Also, per #21673, we need to check the entire document, including
signatures.
parent d6594bfa

src/or/consdiff.c

+24 −14
Original line number Diff line number Diff line
@@ -39,6 +39,15 @@ 
static const char* ns_diff_version = "network-status-diff-version 1";

static const char* hash_token = "hash";



STATIC int

consensus_compute_digest(const char *cons,

                         consensus_digest_t *digest_out)

{

  int r = crypto_digest256((char*)digest_out->sha3_256,

                           cons, strlen(cons), DIGEST_SHA3_256);

  return r;

}



/** Create (allocate) a new slice from a smartlist. Assumes that the start

 * and the end indexes are within the bounds of the initial smartlist. The end

 * element is not part of the resulting slice. If end is -1, the slice is to
@@ -790,7 +799,7 @@ apply_ed_diff(smartlist_t *cons1, smartlist_t *diff) 
 */

smartlist_t *

consdiff_gen_diff(smartlist_t *cons1, smartlist_t *cons2,

                  common_digests_t *digests1, common_digests_t *digests2)

                  consensus_digest_t *digests1, consensus_digest_t *digests2)

{

  smartlist_t *ed_diff = gen_ed_diff(cons1, cons2);

  /* ed diff could not be generated - reason already logged by gen_ed_diff. */
@@ -824,9 +833,9 @@ consdiff_gen_diff(smartlist_t *cons1, smartlist_t *cons2, 
  char cons1_hash_hex[HEX_DIGEST256_LEN+1];

  char cons2_hash_hex[HEX_DIGEST256_LEN+1];

  base16_encode(cons1_hash_hex, HEX_DIGEST256_LEN+1,

      digests1->d[DIGEST_SHA256], DIGEST256_LEN);

                (const char*)digests1->sha3_256, DIGEST256_LEN);

  base16_encode(cons2_hash_hex, HEX_DIGEST256_LEN+1,

      digests2->d[DIGEST_SHA256], DIGEST256_LEN);

                (const char*)digests2->sha3_256, DIGEST256_LEN);



  /* Create the resulting consensus diff. */

  smartlist_t *result = smartlist_new();
@@ -874,7 +883,7 @@ consdiff_get_digests(smartlist_t *diff, 
    goto error_cleanup;

  }



  /* Grab the SHA256 base16 hashes. */

  /* Grab the base16 digests. */

  hash_words = smartlist_new();

  smartlist_split_string(hash_words, smartlist_get(diff, 1), " ", 0, 0);
@@ -889,7 +898,7 @@ consdiff_get_digests(smartlist_t *diff, 
  /* Expected hashes as found in the consensus diff header. They must be of

   * length HEX_DIGEST256_LEN, normally 64 hexadecimal characters.

   * If any of the decodings fail, error to make sure that the hashes are

   * proper base16-encoded SHA256 digests.

   * proper base16-encoded digests.

   */

  cons1_hash_hex = smartlist_get(hash_words, 1);

  cons2_hash_hex = smartlist_get(hash_words, 2);
@@ -936,7 +945,7 @@ consdiff_get_digests(smartlist_t *diff, 
 */

char *

consdiff_apply_diff(smartlist_t *cons1, smartlist_t *diff,

                    common_digests_t *digests1)

                    consensus_digest_t *digests1)

{

  smartlist_t *cons2 = NULL;

  char *cons2_str = NULL;
@@ -948,7 +957,7 @@ consdiff_apply_diff(smartlist_t *cons1, smartlist_t *diff, 
  }



  /* See that the consensus that was given to us matches its hash. */

  if (fast_memneq(digests1->d[DIGEST_SHA256], e_cons1_hash,

  if (fast_memneq(digests1->sha3_256, e_cons1_hash,

                  DIGEST256_LEN)) {

    char hex_digest1[HEX_DIGEST256_LEN+1];

    char e_hex_digest1[HEX_DIGEST256_LEN+1];
@@ -956,7 +965,7 @@ consdiff_apply_diff(smartlist_t *cons1, smartlist_t *diff, 
        "the base consensus doesn't match the digest as found in "

        "the consensus diff header.");

    base16_encode(hex_digest1, HEX_DIGEST256_LEN+1,

        digests1->d[DIGEST_SHA256], DIGEST256_LEN);

                  (const char *)digests1->sha3_256, DIGEST256_LEN);

    base16_encode(e_hex_digest1, HEX_DIGEST256_LEN+1,

                  e_cons1_hash, DIGEST256_LEN);

    log_warn(LD_CONSDIFF, "Expected: %s; found: %s",
@@ -983,16 +992,17 @@ consdiff_apply_diff(smartlist_t *cons1, smartlist_t *diff, 


  cons2_str = smartlist_join_strings(cons2, "\n", 1, NULL);



  common_digests_t cons2_digests;

  if (router_get_networkstatus_v3_hashes(cons2_str,

                                         &cons2_digests)<0) {

  consensus_digest_t cons2_digests;

  if (consensus_compute_digest(cons2_str, &cons2_digests) < 0) {

    /* LCOV_EXCL_START -- digest can't fail */

    log_warn(LD_CONSDIFF, "Could not compute digests of the consensus "

        "resulting from applying a consensus diff.");

    goto error_cleanup;

    /* LCOV_EXCL_STOP */

  }



  /* See that the resulting consensus matches its hash. */

  if (fast_memneq(cons2_digests.d[DIGEST_SHA256], e_cons2_hash,

  if (fast_memneq(cons2_digests.sha3_256, e_cons2_hash,

                  DIGEST256_LEN)) {

    log_warn(LD_CONSDIFF, "Refusing to apply consensus diff because "

        "the resulting consensus doesn't match the digest as found in "
@@ -1000,7 +1010,7 @@ consdiff_apply_diff(smartlist_t *cons1, smartlist_t *diff, 
    char hex_digest2[HEX_DIGEST256_LEN+1];

    char e_hex_digest2[HEX_DIGEST256_LEN+1];

    base16_encode(hex_digest2, HEX_DIGEST256_LEN+1,

        cons2_digests.d[DIGEST_SHA256], DIGEST256_LEN);

        (const char *)cons2_digests.sha3_256, DIGEST256_LEN);

    base16_encode(e_hex_digest2, HEX_DIGEST256_LEN+1,

        e_cons2_hash, DIGEST256_LEN);

    log_warn(LD_CONSDIFF, "Expected: %s; found: %s",

src/or/consdiff.h

+8 −2
Original line number Diff line number Diff line
@@ -7,10 +7,14 @@ 


#include "or.h"



typedef struct consensus_digest_t {

  uint8_t sha3_256[DIGEST256_LEN];

} consensus_digest_t;



smartlist_t *consdiff_gen_diff(smartlist_t *cons1, smartlist_t *cons2,

                  common_digests_t *digests1, common_digests_t *digests2);

                  consensus_digest_t *digests1, consensus_digest_t *digests2);

char *consdiff_apply_diff(smartlist_t *cons1, smartlist_t *diff,

                    common_digests_t *digests1);

                    consensus_digest_t *digests1);

int consdiff_get_digests(smartlist_t *diff,

                         char *digest1_out,

                         char *digest2_out);
@@ -45,6 +49,8 @@ STATIC int smartlist_slice_string_pos(smartlist_slice_t *slice, 
                                      const char *string);

STATIC void set_changed(bitarray_t *changed1, bitarray_t *changed2,

                        smartlist_slice_t *slice1, smartlist_slice_t *slice2);

STATIC int consensus_compute_digest(const char *cons,

                                    consensus_digest_t *digest_out);

#endif



#endif

src/test/test_consdiff.c

+39 −37
Original line number Diff line number Diff line
@@ -8,7 +8,6 @@ 
#include "test.h"



#include "consdiff.h"

#include "routerparse.h"

#include "log_test_helpers.h"



static void
@@ -808,7 +807,7 @@ test_consdiff_gen_diff(void *arg) 
{

  char *cons1_str=NULL, *cons2_str=NULL;

  smartlist_t *cons1=NULL, *cons2=NULL, *diff=NULL;

  common_digests_t digests1, digests2;

  consensus_digest_t digests1, digests2;

  (void)arg;

  cons1 = smartlist_new();

  cons2 = smartlist_new();
@@ -817,22 +816,22 @@ test_consdiff_gen_diff(void *arg) 
   * Already tested in gen_ed_diff, but see that a NULL ed diff also makes

   * gen_diff return NULL. */

  cons1_str = tor_strdup(

      "header\nnetwork-status-version foo\n"

      "network-status-version foo\n"

      "r name bbbbbbbbbbbbbbbbb etc\nfoo\n"

      "r name aaaaaaaaaaaaaaaaa etc\nbar\n"

      "directory-signature foo bar\nbar\n"

      );

  cons2_str = tor_strdup(

      "header\nnetwork-status-version foo\n"

      "network-status-version foo\n"

      "r name aaaaaaaaaaaaaaaaa etc\nfoo\n"

      "r name ccccccccccccccccc etc\nbar\n"

      "directory-signature foo bar\nbar\n"

      );



  tt_int_op(0, OP_EQ,

      router_get_networkstatus_v3_hashes(cons1_str, &digests1));

      consensus_compute_digest(cons1_str, &digests1));

  tt_int_op(0, OP_EQ,

      router_get_networkstatus_v3_hashes(cons2_str, &digests2));

      consensus_compute_digest(cons2_str, &digests2));



  tor_split_lines(cons1, cons1_str, (int)strlen(cons1_str));

  tor_split_lines(cons2, cons2_str, (int)strlen(cons2_str));
@@ -843,13 +842,13 @@ test_consdiff_gen_diff(void *arg) 
  /* Check that the headers are done properly. */

  tor_free(cons1_str);

  cons1_str = tor_strdup(

      "header\nnetwork-status-version foo\n"

      "network-status-version foo\n"

      "r name ccccccccccccccccc etc\nfoo\n"

      "r name eeeeeeeeeeeeeeeee etc\nbar\n"

      "directory-signature foo bar\nbar\n"

      );

  tt_int_op(0, OP_EQ,

      router_get_networkstatus_v3_hashes(cons1_str, &digests1));

      consensus_compute_digest(cons1_str, &digests1));

  smartlist_clear(cons1);

  tor_split_lines(cons1, cons1_str, (int)strlen(cons1_str));

  diff = consdiff_gen_diff(cons1, cons2, &digests1, &digests2);
@@ -857,11 +856,11 @@ test_consdiff_gen_diff(void *arg) 
  tt_int_op(7, OP_EQ, smartlist_len(diff));

  tt_str_op("network-status-diff-version 1", OP_EQ, smartlist_get(diff, 0));

  tt_str_op("hash "

      "C2199B6827514F39ED9B3F2E2E73735C6C5468FD636240BB454C526220DE702A "

      "B193E5FBFE5C009AEDE56F9218E6421A1AE5C19F43E091786A73F43F60409B60",

      "06646D6CF563A41869D3B02E73254372AE3140046C5E7D83C9F71E54976AF9B4 "

      "7AFECEFA4599BA33D603653E3D2368F648DF4AC4723929B0F7CF39281596B0C1",

      OP_EQ, smartlist_get(diff, 1));

  tt_str_op("4,5d", OP_EQ, smartlist_get(diff, 2));

  tt_str_op("2a", OP_EQ, smartlist_get(diff, 3));

  tt_str_op("3,4d", OP_EQ, smartlist_get(diff, 2));

  tt_str_op("1a", OP_EQ, smartlist_get(diff, 3));

  tt_str_op("r name aaaaaaaaaaaaaaaaa etc", OP_EQ, smartlist_get(diff, 4));

  tt_str_op("foo", OP_EQ, smartlist_get(diff, 5));

  tt_str_op(".", OP_EQ, smartlist_get(diff, 6));
@@ -882,20 +881,20 @@ test_consdiff_apply_diff(void *arg) 
{

  smartlist_t *cons1=NULL, *diff=NULL;

  char *cons1_str=NULL, *cons2 = NULL;

  common_digests_t digests1;

  consensus_digest_t digests1;

  (void)arg;

  cons1 = smartlist_new();

  diff = smartlist_new();

  setup_capture_of_logs(LOG_INFO);



  cons1_str = tor_strdup(

      "header\nnetwork-status-version foo\n"

      "network-status-version foo\n"

      "r name ccccccccccccccccc etc\nfoo\n"

      "r name eeeeeeeeeeeeeeeee etc\nbar\n"

      "directory-signature foo bar\nbar\n"

      );

  tt_int_op(0, OP_EQ,

      router_get_networkstatus_v3_hashes(cons1_str, &digests1));

      consensus_compute_digest(cons1_str, &digests1));

  tor_split_lines(cons1, cons1_str, (int)strlen(cons1_str));



  /* diff doesn't have enough lines. */
@@ -930,7 +929,7 @@ test_consdiff_apply_diff(void *arg) 
  tt_ptr_op(NULL, OP_EQ, cons2);

  expect_single_log_msg_containing("does not include the necessary digests")



  /* base16 sha256 digests do not have the expected length. */

  /* base16 digests do not have the expected length. */

  smartlist_clear(diff);

  smartlist_add(diff, (char*)"network-status-diff-version 1");

  smartlist_add(diff, (char*)"hash aaa bbb");
@@ -940,7 +939,7 @@ test_consdiff_apply_diff(void *arg) 
  expect_single_log_msg_containing("includes base16-encoded digests of "

                                   "incorrect size")



  /* base16 sha256 digests contain non-base16 characters. */

  /* base16 digests contain non-base16 characters. */

  smartlist_clear(diff);

  smartlist_add(diff, (char*)"network-status-diff-version 1");

  smartlist_add(diff, (char*)"hash"
@@ -957,8 +956,8 @@ test_consdiff_apply_diff(void *arg) 
  smartlist_clear(diff);

  smartlist_add(diff, (char*)"network-status-diff-version 1");

  smartlist_add(diff, (char*)"hash"

      /* sha256 of cons1. */

      " C2199B6827514F39ED9B3F2E2E73735C6C5468FD636240BB454C526220DE702A"

      /* sha3 of cons1. */

      " 06646D6CF563A41869D3B02E73254372AE3140046C5E7D83C9F71E54976AF9B4"

      /* sha256 of cons2. */

      " 635D34593020C08E5ECD865F9986E29D50028EFA62843766A8197AD228A7F6AA");

  smartlist_add(diff, (char*)"foobar");
@@ -986,9 +985,9 @@ test_consdiff_apply_diff(void *arg) 
  smartlist_clear(diff);

  smartlist_add(diff, (char*)"network-status-diff-version 1");

  smartlist_add(diff, (char*)"hash"

      /* sha256 of cons1. */

      " C2199B6827514F39ED9B3F2E2E73735C6C5468FD636240BB454C526220DE702A"

      /* bogus sha256. */

      /* sha3 of cons1. */

      " 06646D6CF563A41869D3B02E73254372AE3140046C5E7D83C9F71E54976AF9B4"

      /* bogus sha3. */

      " 3333333333333333333333333333333333333333333333333333333333333333");

  mock_clean_saved_logs();

  cons2 = consdiff_apply_diff(cons1, diff, &digests1);
@@ -996,13 +995,15 @@ test_consdiff_apply_diff(void *arg) 
  expect_log_msg_containing("resulting consensus doesn't match the "

                            "digest as found");



#if 0

  /* XXXX No longer possible, since we aren't using the other algorithm. */

  /* Resulting consensus digest cannot be computed */

  smartlist_clear(diff);

  smartlist_add(diff, (char*)"network-status-diff-version 1");

  smartlist_add(diff, (char*)"hash"

      /* sha256 of cons1. */

      " C2199B6827514F39ED9B3F2E2E73735C6C5468FD636240BB454C526220DE702A"

      /* bogus sha256. */

      /* sha3 of cons1. */

      " 06646D6CF563A41869D3B02E73254372AE3140046C5E7D83C9F71E54976AF9B4"

      /* bogus sha3. */

      " 3333333333333333333333333333333333333333333333333333333333333333");

  smartlist_add(diff, (char*)"1,2d"); // remove starting line

  mock_clean_saved_logs();
@@ -1010,22 +1011,23 @@ test_consdiff_apply_diff(void *arg) 
  tt_ptr_op(NULL, OP_EQ, cons2);

  expect_log_msg_containing("Could not compute digests of the consensus "

                            "resulting from applying a consensus diff.");

#endif



  /* Very simple test, only to see that nothing errors. */

  smartlist_clear(diff);

  smartlist_add(diff, (char*)"network-status-diff-version 1");

  smartlist_add(diff, (char*)"hash"

      /* sha256 of cons1. */

      " C2199B6827514F39ED9B3F2E2E73735C6C5468FD636240BB454C526220DE702A"

      /* sha256 of cons2. */

      " 635D34593020C08E5ECD865F9986E29D50028EFA62843766A8197AD228A7F6AA");

  smartlist_add(diff, (char*)"4c");

      /* sha3 of cons1. */

      " 06646D6CF563A41869D3B02E73254372AE3140046C5E7D83C9F71E54976AF9B4"

      /* sha3 of cons2. */

      " 90A418881B2FCAB3D9E60EE02E4D666D56CFA38F8A3B7AA3E0ADBA530DDA9353");

  smartlist_add(diff, (char*)"3c");

  smartlist_add(diff, (char*)"sample");

  smartlist_add(diff, (char*)".");

  cons2 = consdiff_apply_diff(cons1, diff, &digests1);

  tt_ptr_op(NULL, OP_NE, cons2);

  tt_str_op(

      "header\nnetwork-status-version foo\n"

      "network-status-version foo\n"

      "r name ccccccccccccccccc etc\nsample\n"

      "r name eeeeeeeeeeeeeeeee etc\nbar\n"

      "directory-signature foo bar\nbar\n", OP_EQ,
@@ -1036,17 +1038,17 @@ test_consdiff_apply_diff(void *arg) 
  smartlist_clear(diff);

  smartlist_add(diff, (char*)"network-status-diff-version 1");

  smartlist_add(diff, (char*)"hash"

      /* sha256 of cons1. */

      " c2199b6827514f39ed9b3f2e2e73735c6c5468fd636240bb454c526220de702a"

      /* sha256 of cons2. */

      " 635d34593020c08e5ecd865f9986e29d50028efa62843766a8197ad228a7f6aa");

  smartlist_add(diff, (char*)"4c");

      /* sha3 of cons1. */

      " 06646d6cf563a41869d3b02e73254372ae3140046c5e7d83c9f71e54976af9b4"

      /* sha3 of cons2. */

      " 90a418881b2fcab3d9e60ee02e4d666d56cfa38f8a3b7aa3e0adba530dda9353");

  smartlist_add(diff, (char*)"3c");

  smartlist_add(diff, (char*)"sample");

  smartlist_add(diff, (char*)".");

  cons2 = consdiff_apply_diff(cons1, diff, &digests1);

  tt_ptr_op(NULL, OP_NE, cons2);

  tt_str_op(

      "header\nnetwork-status-version foo\n"

      "network-status-version foo\n"

      "r name ccccccccccccccccc etc\nsample\n"

      "r name eeeeeeeeeeeeeeeee etc\nbar\n"

      "directory-signature foo bar\nbar\n", OP_EQ,