commit d827902cb1107593473552974be5fcbb1fbb4abe Author: rl1987 rl1987@sdf.lonestar.org Date: Sat Oct 20 20:15:06 2018 +0300

Unit test for DNS fallback in configure_nameservers --- src/feature/relay/dns.c | 30 ++++++++++++++++++++++++ src/feature/relay/dns.h | 3 +++ src/test/test_dns.c | 61 +++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 94 insertions(+)

diff --git a/src/feature/relay/dns.c b/src/feature/relay/dns.c index f056629b8..1b4914b49 100644 --- a/src/feature/relay/dns.c +++ b/src/feature/relay/dns.c @@ -1357,6 +1357,36 @@ evdns_err_is_transient(int err) } }

+/** + * Return number of configured nameservers in <b>the_evdns_base</b>. + */ +size_t +number_of_configured_nameservers(void) +{ + return evdns_base_count_nameservers(the_evdns_base); +} + +/** + * Return address of configured nameserver in <b>the_evdns_base</b> + * at index <b>idx</b>. + */ +tor_addr_t * +configured_nameserver_address(const size_t idx) +{ + struct sockaddr_storage sa; + ev_socklen_t sa_len = sizeof(sa); + + if (evdns_base_get_nameserver_addr(the_evdns_base, (int)idx, + (struct sockaddr *)&sa, + sa_len) > 0) { + tor_addr_t *tor_addr = tor_malloc(sizeof(tor_addr_t)); + tor_addr_from_sockaddr(tor_addr, (const struct sockaddr *)&sa, NULL); + return tor_addr; + } + + return NULL; +} + /** Configure eventdns nameservers if force is true, or if the configuration * has changed since the last time we called this function, or if we failed on * our last attempt. On Unix, this reads from /etc/resolv.conf or diff --git a/src/feature/relay/dns.h b/src/feature/relay/dns.h index 1dd6f903d..3a17ea7b3 100644 --- a/src/feature/relay/dns.h +++ b/src/feature/relay/dns.h @@ -45,6 +45,9 @@ size_t dns_cache_handle_oom(time_t now, size_t min_remove_bytes); #ifdef DNS_PRIVATE #include "feature/relay/dns_structs.h"

+size_t number_of_configured_nameservers(void); +tor_addr_t *configured_nameserver_address(const size_t idx); + MOCK_DECL(STATIC int,dns_resolve_impl,(edge_connection_t *exitconn, int is_resolve,or_circuit_t *oncirc, char **hostname_out, int *made_connection_pending_out, cached_resolve_t **resolve_out)); diff --git a/src/test/test_dns.c b/src/test/test_dns.c index 8369f844f..ea59a49b5 100644 --- a/src/test/test_dns.c +++ b/src/test/test_dns.c @@ -13,9 +13,69 @@

#include "core/or/edge_connection_st.h" #include "core/or/or_circuit_st.h" +#include "app/config/or_options_st.h" +#include "app/config/config.h" + +#include <event2/event.h> +#include <event2/dns.h>

#define NS_MODULE dns

+#define NS_SUBMODULE configure_nameservers_fallback + +static or_options_t options = { + .ORPort_set = 1, +}; + +static const or_options_t * +mock_get_options(void) +{ + return &options; +} + +static void +NS(test_main)(void *arg) +{ + (void)arg; + tor_addr_t *nameserver_addr = NULL; + + MOCK(get_options, mock_get_options); + + options.ServerDNSResolvConfFile = (char *)"no_such_file!!!"; + + dns_init(); // calls configure_nameservers() + + tt_int_op(number_of_configured_nameservers(), OP_EQ, 1); + + nameserver_addr = configured_nameserver_address(0); + + tt_assert(tor_addr_family(nameserver_addr) == AF_INET); + tt_assert(tor_addr_eq_ipv4h(nameserver_addr, 0x7f000001)); + +#ifndef _WIN32 + tor_free(nameserver_addr); + + options.ServerDNSResolvConfFile = (char *)"/dev/null"; + + dns_init(); + + tt_int_op(number_of_configured_nameservers(), OP_EQ, 1); + + nameserver_addr = configured_nameserver_address(0); + + tt_assert(tor_addr_family(nameserver_addr) == AF_INET); + tt_assert(tor_addr_eq_ipv4h(nameserver_addr, 0x7f000001)); +#endif + + UNMOCK(get_options); + + done: + tor_free(nameserver_addr); + return; +} + +#undef NS_SUBMODULE + #define NS_SUBMODULE clip_ttl

static void @@ -736,6 +796,7 @@ NS(test_main)(void *arg) #undef NS_SUBMODULE

struct testcase_t dns_tests[] = { + TEST_CASE(configure_nameservers_fallback), TEST_CASE(clip_ttl), TEST_CASE(resolve), TEST_CASE_ASPECT(resolve_impl, addr_is_ip_no_need_to_resolve),