diff options
| author | Rasmus Dahlberg <rasmus@mullvad.net> | 2022-10-12 20:29:11 +0200 |
|---|---|---|
| committer | David Goulet <dgoulet@torproject.org> | 2022-11-09 15:30:43 -0500 |
| commit | 21eac1e8d8a116f2dd8dd0a7d150916646ee9120 (patch) | |
| tree | 783574117b03f82fa0238fcdac4fc0637c02c269 /src/test/test_dns.c | |
| parent | 0fe2096144104e63d403896844af121c9622a7a8 (diff) | |
| download | tor-21eac1e8d8a116f2dd8dd0a7d150916646ee9120.tar.gz tor-21eac1e8d8a116f2dd8dd0a7d150916646ee9120.zip | |
dns: Make TTLs fuzzy at exit relays
This change mitigates DNS-based website oracles by making the time that
a domain name is cached uncertain (+- 4 minutes of what's measurable).
Resolves TROVE-2021-009.
Fixes #40674
Diffstat (limited to 'src/test/test_dns.c')
| -rw-r--r-- | src/test/test_dns.c | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/src/test/test_dns.c b/src/test/test_dns.c index dc38b53e0f..6612391127 100644 --- a/src/test/test_dns.c +++ b/src/test/test_dns.c @@ -90,6 +90,36 @@ test_dns_clip_ttl(void *arg) return; } +static void +test_dns_clip_fuzzy_ttl(void *arg) +{ + (void)arg; + + /* Case 0: check that the fuzzy TTL constant is valid + */ + tt_int_op(FUZZY_DNS_TTL, OP_LE, MIN_DNS_TTL); + tt_int_op(FUZZY_DNS_TTL, OP_LE, MAX_DNS_TTL); + + /* Case 1: low clips + */ + for (int i = 0; i < 1024; i++) { + int fuzzy_ttl = clip_dns_fuzzy_ttl(MIN_DNS_TTL - 1); + tt_int_op(fuzzy_ttl, OP_GE, MIN_DNS_TTL-FUZZY_DNS_TTL); + tt_int_op(fuzzy_ttl, OP_LE, MIN_DNS_TTL+FUZZY_DNS_TTL); + } + + /* Case 2: high clips + */ + for (int i = 0; i < 1024; i++) { + int fuzzy_ttl = clip_dns_fuzzy_ttl(MIN_DNS_TTL); + tt_int_op(fuzzy_ttl, OP_GE, MAX_DNS_TTL-FUZZY_DNS_TTL); + tt_int_op(fuzzy_ttl, OP_LE, MAX_DNS_TTL+FUZZY_DNS_TTL); + } + + done: + return; +} + static int resolve_retval = 0; static int resolve_made_conn_pending = 0; static char *resolved_name = NULL; @@ -779,6 +809,7 @@ struct testcase_t dns_tests[] = { TT_FORK, NULL, NULL }, #endif { "clip_ttl", test_dns_clip_ttl, TT_FORK, NULL, NULL }, + { "clip_fuzzy_ttl", test_dns_clip_fuzzy_ttl, TT_FORK, NULL, NULL }, { "resolve", test_dns_resolve, TT_FORK, NULL, NULL }, { "impl_addr_is_ip", test_dns_impl_addr_is_ip, TT_FORK, NULL, NULL }, { "impl_non_exit", test_dns_impl_non_exit, TT_FORK, NULL, NULL }, |