tor/src/test/test_extorport.c

/* Copyright (c) 2013, The Tor Project, Inc. */
/* See LICENSE for licensing information */

#define CONNECTION_PRIVATE
#define EXT_ORPORT_PRIVATE
#include "or.h"
#include "buffers.h"
#include "connection.h"
#include "ext_orport.h"
#include "test.h"

/* Test connection_or_remove_from_ext_or_id_map and
 * connection_or_set_ext_or_identifier */
static void
test_ext_or_id_map(void *arg)
{
  or_connection_t *c1 = NULL, *c2 = NULL, *c3 = NULL;
  char *idp = NULL, *idp2 = NULL;
  (void)arg;

  /* pre-initialization */
  tt_ptr_op(NULL, ==, connection_or_get_by_ext_or_id("xxxxxxxxxxxxxxxxxxxx"));

  c1 = or_connection_new(CONN_TYPE_EXT_OR, AF_INET);
  c2 = or_connection_new(CONN_TYPE_EXT_OR, AF_INET);
  c3 = or_connection_new(CONN_TYPE_OR, AF_INET);

  tt_ptr_op(c1->ext_or_conn_id, !=, NULL);
  tt_ptr_op(c2->ext_or_conn_id, !=, NULL);
  tt_ptr_op(c3->ext_or_conn_id, ==, NULL);

  tt_ptr_op(c1, ==, connection_or_get_by_ext_or_id(c1->ext_or_conn_id));
  tt_ptr_op(c2, ==, connection_or_get_by_ext_or_id(c2->ext_or_conn_id));
  tt_ptr_op(NULL, ==, connection_or_get_by_ext_or_id("xxxxxxxxxxxxxxxxxxxx"));

  idp = tor_memdup(c2->ext_or_conn_id, EXT_OR_CONN_ID_LEN);

  /* Give c2 a new ID. */
  connection_or_set_ext_or_identifier(c2);
  test_mem_op(idp, !=, c2->ext_or_conn_id, EXT_OR_CONN_ID_LEN);
  idp2 = tor_memdup(c2->ext_or_conn_id, EXT_OR_CONN_ID_LEN);
  tt_assert(!tor_digest_is_zero(idp2));

  tt_ptr_op(NULL, ==, connection_or_get_by_ext_or_id(idp));
  tt_ptr_op(c2, ==, connection_or_get_by_ext_or_id(idp2));

  /* Now remove it. */
  connection_or_remove_from_ext_or_id_map(c2);
  tt_ptr_op(NULL, ==, connection_or_get_by_ext_or_id(idp));
  tt_ptr_op(NULL, ==, connection_or_get_by_ext_or_id(idp2));

 done:
  if (c1)
    connection_free_(TO_CONN(c1));
  if (c2)
    connection_free_(TO_CONN(c2));
  if (c3)
    connection_free_(TO_CONN(c3));
  tor_free(idp);
  tor_free(idp2);
  connection_or_clear_ext_or_id_map();
}

/* Simple connection_write_to_buf_impl_ replacement that unconditionally
 * writes to outbuf. */
static void
connection_write_to_buf_impl_replacement(const char *string, size_t len,
                                         connection_t *conn, int zlib)
{
  (void) zlib;

  tor_assert(string);
  tor_assert(conn);
  write_to_buf(string, len, conn->outbuf);
}

static char *
buf_get_contents(buf_t *buf, size_t *sz_out)
{
  char *out;
  *sz_out = buf_datalen(buf);
  if (*sz_out >= ULONG_MAX)
    return NULL; /* C'mon, really? */
  out = tor_malloc(*sz_out + 1);
  if (fetch_from_buf(out, (unsigned long)*sz_out, buf) != 0) {
    tor_free(out);
    return NULL;
  }
  out[*sz_out] = '\0'; /* Hopefully gratuitous. */
  return out;
}

static void
test_ext_or_write_command(void *arg)
{
  or_connection_t *c1;
  char *cp = NULL;
  char *buf = NULL;
  size_t sz;

  (void) arg;
  MOCK(connection_write_to_buf_impl_,
       connection_write_to_buf_impl_replacement);

  c1 = or_connection_new(CONN_TYPE_EXT_OR, AF_INET);
  tt_assert(c1);

  /* Length too long */
  tt_int_op(connection_write_ext_or_command(TO_CONN(c1), 100, "X", 100000),
            <, 0);

  /* Empty command */
  tt_int_op(connection_write_ext_or_command(TO_CONN(c1), 0x99, NULL, 0),
            ==, 0);
  cp = buf_get_contents(TO_CONN(c1)->outbuf, &sz);
  tt_int_op(sz, ==, 4);
  test_mem_op(cp, ==, "\x00\x99\x00\x00", 4);
  tor_free(cp);

  /* Medium command. */
  tt_int_op(connection_write_ext_or_command(TO_CONN(c1), 0x99,
                                            "Wai\0Hello", 9), ==, 0);
  cp = buf_get_contents(TO_CONN(c1)->outbuf, &sz);
  tt_int_op(sz, ==, 13);
  test_mem_op(cp, ==, "\x00\x99\x00\x09Wai\x00Hello", 13);
  tor_free(cp);

  /* Long command */
  buf = tor_malloc(65535);
  memset(buf, 'x', 65535);
  tt_int_op(connection_write_ext_or_command(TO_CONN(c1), 0xf00d,
                                            buf, 65535), ==, 0);
  cp = buf_get_contents(TO_CONN(c1)->outbuf, &sz);
  tt_int_op(sz, ==, 65539);
  test_mem_op(cp, ==, "\xf0\x0d\xff\xff", 4);
  test_mem_op(cp+4, ==, buf, 65535);
  tor_free(cp);

 done:
  if (c1)
    connection_free_(TO_CONN(c1));
  tor_free(cp);
  tor_free(buf);
  UNMOCK(connection_write_to_buf_impl_);
}

static void
test_ext_or_cookie_auth(void *arg)
{
  char *reply=NULL, *reply2=NULL, *client_hash=NULL, *client_hash2=NULL;
  size_t reply_len=0;
  char hmac1[32], hmac2[32];

  const char client_nonce[32] =
    "Who is the third who walks alway";
  char server_hash_input[] =
    "ExtORPort authentication server-to-client hash"
    "Who is the third who walks alway"
    "................................";
  char client_hash_input[] =
    "ExtORPort authentication client-to-server hash"
    "Who is the third who walks alway"
    "................................";

  (void)arg;

  tt_int_op(strlen(client_hash_input), ==, 46+32+32);
  tt_int_op(strlen(server_hash_input), ==, 46+32+32);

  memcpy(ext_or_auth_cookie, "s beside you? When I count, ther", 32);
  ext_or_auth_cookie_is_set = 1;

  /* For this authentication, the client sends 32 random bytes (ClientNonce)
   * The server replies with 32 byte ServerHash and 32 byte ServerNonce,
   * where ServerHash is:
   * HMAC-SHA256(CookieString,
   *   "ExtORPort authentication server-to-client hash" | ClientNonce |
   *    ServerNonce)"
   * The client must reply with 32-byte ClientHash, which we compute as:
   *   ClientHash is computed as:
   *        HMAC-SHA256(CookieString,
   *           "ExtORPort authentication client-to-server hash" | ClientNonce |
   *            ServerNonce)
   */

  /* Wrong length */
  tt_int_op(-1, ==,
            handle_client_auth_nonce(client_nonce, 33, &client_hash, &reply,
                                     &reply_len));
  tt_int_op(-1, ==,
            handle_client_auth_nonce(client_nonce, 31, &client_hash, &reply,
                                     &reply_len));

  /* Now let's try this for real! */
  tt_int_op(0, ==,
            handle_client_auth_nonce(client_nonce, 32, &client_hash, &reply,
                                     &reply_len));
  tt_int_op(reply_len, ==, 64);
  tt_ptr_op(reply, !=, NULL);
  tt_ptr_op(client_hash, !=, NULL);
  /* Fill in the server nonce into the hash inputs... */
  memcpy(server_hash_input+46+32, reply+32, 32);
  memcpy(client_hash_input+46+32, reply+32, 32);
  /* Check the HMACs are correct... */
  crypto_hmac_sha256(hmac1, ext_or_auth_cookie, 32, server_hash_input,
                     46+32+32);
  crypto_hmac_sha256(hmac2, ext_or_auth_cookie, 32, client_hash_input,
                     46+32+32);
  test_memeq(hmac1, reply, 32);
  test_memeq(hmac2, client_hash, 32);

  /* Now do it again and make sure that the results are *different* */
  tt_int_op(0, ==,
            handle_client_auth_nonce(client_nonce, 32, &client_hash2, &reply2,
                                     &reply_len));
  test_memneq(reply2, reply, reply_len);
  test_memneq(client_hash2, client_hash, 32);
  /* But that this one checks out too. */
  memcpy(server_hash_input+46+32, reply2+32, 32);
  memcpy(client_hash_input+46+32, reply2+32, 32);
  /* Check the HMACs are correct... */
  crypto_hmac_sha256(hmac1, ext_or_auth_cookie, 32, server_hash_input,
                     46+32+32);
  crypto_hmac_sha256(hmac2, ext_or_auth_cookie, 32, client_hash_input,
                     46+32+32);
  test_memeq(hmac1, reply2, 32);
  test_memeq(hmac2, client_hash2, 32);

 done:
  tor_free(reply);
  tor_free(client_hash);
  tor_free(reply2);
  tor_free(client_hash2);
}

static int
crypto_rand_return_tse_str(char *to, size_t n)
{
  if (n != 32) {
    TT_FAIL(("Asked for %d bytes, not 32", (int)n));
    return -1;
  }
  memcpy(to, "te road There is always another ", 32);
  return 0;
}

static void
test_ext_or_cookie_auth_testvec(void *arg)
{
  char *reply=NULL, *client_hash=NULL;
  size_t reply_len;
  char *mem_op_hex_tmp=NULL;

  const char client_nonce[] = "But when I look ahead up the whi";
  (void)arg;

  memcpy(ext_or_auth_cookie, "Gliding wrapt in a brown mantle," , 32);
  ext_or_auth_cookie_is_set = 1;

  MOCK(crypto_rand, crypto_rand_return_tse_str);

  tt_int_op(0, ==,
            handle_client_auth_nonce(client_nonce, 32, &client_hash, &reply,
                                     &reply_len));
  tt_ptr_op(reply, !=, NULL );
  tt_ptr_op(reply_len, ==, 64);
  test_memeq(reply+32, "te road There is always another ", 32);
  /* HMACSHA256("Gliding wrapt in a brown mantle,"
   *     "ExtORPort authentication server-to-client hash"
   *     "But when I look ahead up the write road There is always another ");
   */
  test_memeq_hex(reply,
                 "ec80ed6e546d3b36fdfc22fe1315416b"
                 "029f1ade7610d910878b62eeb7403821");
  /* HMACSHA256("Gliding wrapt in a brown mantle,"
   *     "ExtORPort authentication client-to-server hash"
   *     "But when I look ahead up the write road There is always another ");
   * (Both values computed using Python CLI.)
   */
  test_memeq_hex(client_hash,
                 "ab391732dd2ed968cd40c087d1b1f25b"
                 "33b3cd77ff79bd80c2074bbf438119a2");

 done:
  UNMOCK(crypto_rand);
  tor_free(reply);
  tor_free(client_hash);
  tor_free(mem_op_hex_tmp);
}

struct testcase_t extorport_tests[] = {
  { "id_map", test_ext_or_id_map, TT_FORK, NULL, NULL },
  { "write_command", test_ext_or_write_command, TT_FORK, NULL, NULL },
  { "cookie_auth", test_ext_or_cookie_auth, TT_FORK, NULL, NULL },
  { "cookie_auth_testvec", test_ext_or_cookie_auth_testvec, TT_FORK,
    NULL, NULL },
  END_OF_TESTCASES
};