platform_bionic/tests/ifaddrs_test.cpp
Elliott Hughes 5d84373c69 Add a getifaddrs(3) debugging tool.
...disguised as a test, because that's the easiest way to keep an eye on it.

Change-Id: Iec2531183790d12aec561d27645e5d400f69efbf
2016-01-12 08:45:16 -08:00

126 lines
4.4 KiB
C++

/*
* Copyright (C) 2015 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <gtest/gtest.h>
#include <ifaddrs.h>
#include <linux/if_packet.h>
#include <net/ethernet.h>
#include <net/if.h>
#include <netdb.h>
#include <netinet/in.h>
TEST(ifaddrs, freeifaddrs_null) {
freeifaddrs(nullptr);
}
TEST(ifaddrs, getifaddrs_smoke) {
ifaddrs* addrs = nullptr;
ASSERT_EQ(0, getifaddrs(&addrs));
ASSERT_TRUE(addrs != nullptr);
// We can't say much about what network interfaces are available, but we can be pretty
// sure there's a loopback interface, and that it has IPv4, IPv6, and AF_PACKET entries.
ifaddrs* lo_inet4 = nullptr;
ifaddrs* lo_inet6 = nullptr;
ifaddrs* lo_packet = nullptr;
for (ifaddrs* addr = addrs; addr != nullptr; addr = addr->ifa_next) {
if (addr->ifa_name && strcmp(addr->ifa_name, "lo") == 0) {
if (addr->ifa_addr && addr->ifa_addr->sa_family == AF_INET) lo_inet4 = addr;
else if (addr->ifa_addr && addr->ifa_addr->sa_family == AF_INET6) lo_inet6 = addr;
else if (addr->ifa_addr && addr->ifa_addr->sa_family == AF_PACKET) lo_packet = addr;
}
}
// Does the IPv4 entry look right?
ASSERT_TRUE(lo_inet4 != nullptr);
const sockaddr_in* sa_inet4 = reinterpret_cast<const sockaddr_in*>(lo_inet4->ifa_addr);
ASSERT_TRUE(ntohl(sa_inet4->sin_addr.s_addr) == INADDR_LOOPBACK);
// Does the IPv6 entry look right?
ASSERT_TRUE(lo_inet6 != nullptr);
const sockaddr_in6* sa_inet6 = reinterpret_cast<const sockaddr_in6*>(lo_inet6->ifa_addr);
ASSERT_TRUE(IN6_IS_ADDR_LOOPBACK(&sa_inet6->sin6_addr));
// Does the AF_PACKET entry look right?
ASSERT_TRUE(lo_packet != nullptr);
const sockaddr_ll* sa_ll = reinterpret_cast<const sockaddr_ll*>(lo_packet->ifa_addr);
ASSERT_EQ(6, sa_ll->sll_halen);
freeifaddrs(addrs);
}
static void print_sockaddr_ll(const char* what, const sockaddr* p) {
const sockaddr_ll* s = reinterpret_cast<const sockaddr_ll*>(p);
printf("\t%s\t", what);
for (int i = 0; i < s->sll_halen; ++i) {
if (i > 0) printf(":");
printf("%02X", s->sll_addr[i]);
}
printf(" (%d bytes)\n", s->sll_halen);
}
static void print_sockaddr_inet(const char* what, const sockaddr* addr) {
char host[NI_MAXHOST];
int family = addr->sa_family;
int error = getnameinfo(addr,
(family == AF_INET) ? sizeof(sockaddr_in) : sizeof(sockaddr_in6),
host, NI_MAXHOST, nullptr, 0, NI_NUMERICHOST);
if (error != 0) {
printf("%d getnameinfo() failed: %s\n", family, gai_strerror(error));
strcpy(host, "???");
}
printf("\t%s: <%s>\n", what, host);
}
static const char* family_to_name(int family) {
if (family == AF_INET) return "AF_INET";
if (family == AF_INET6) return "AF_INET6";
if (family == AF_PACKET) return "AF_PACKET";
if (family == AF_UNSPEC) return "AF_UNSPEC";
return "?";
}
// Not really a test, but a useful debugging tool.
TEST(ifaddrs, dump) {
ifaddrs* addrs;
ASSERT_EQ(0, getifaddrs(&addrs));
for (ifaddrs* ifa = addrs; ifa != nullptr; ifa = ifa->ifa_next) {
int family = ifa->ifa_addr ? ifa->ifa_addr->sa_family :
ifa->ifa_broadaddr ? ifa->ifa_broadaddr->sa_family : AF_UNSPEC;
printf("%s\n\t%s (%d) flags=%#x\n",
ifa->ifa_name, family_to_name(family), family, ifa->ifa_flags);
if (family == AF_PACKET) {
if (ifa->ifa_addr) print_sockaddr_ll("hwaddr", ifa->ifa_addr);
if (ifa->ifa_broadaddr) print_sockaddr_ll("hwbroad", ifa->ifa_addr);
} else if (family == AF_INET || family == AF_INET6) {
if (ifa->ifa_addr) print_sockaddr_inet("address", ifa->ifa_addr);
if (ifa->ifa_broadaddr && (ifa->ifa_flags & (IFF_BROADCAST | IFF_POINTOPOINT)) != 0) {
print_sockaddr_inet((ifa->ifa_flags & IFF_BROADCAST) ? "broadcast" : "destination",
ifa->ifa_broadaddr);
}
}
fflush(stdout);
}
freeifaddrs(addrs);
}