Handle AF_PACKET in getifaddr(3).
Also fix a bug where we were mutating the address/broadcast address
of an existing entry rather than the new entry, and use 'const' to
ensure we don't make that mistake again.
Change-Id: I31c127a5d21879b52c85cd0f7ed2e66554a21e39
diff --git a/libc/bionic/ifaddrs.cpp b/libc/bionic/ifaddrs.cpp
index c869420..b66883e 100644
--- a/libc/bionic/ifaddrs.cpp
+++ b/libc/bionic/ifaddrs.cpp
@@ -29,6 +29,7 @@
#include <ifaddrs.h>
#include <errno.h>
+#include <linux/if_packet.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <net/if.h>
@@ -93,6 +94,13 @@
ifa.ifa_netmask = reinterpret_cast<sockaddr*>(&netmask);
}
+ void SetPacketAttributes(int ifindex, unsigned short hatype, unsigned char halen) {
+ sockaddr_ll* sll = reinterpret_cast<sockaddr_ll*>(&addr);
+ sll->sll_ifindex = ifindex;
+ sll->sll_hatype = hatype;
+ sll->sll_halen = halen;
+ }
+
private:
// Returns a pointer to the first byte in the address data (which is
// stored in network byte order).
@@ -103,6 +111,9 @@
} else if (family == AF_INET6) {
sockaddr_in6* ss6 = reinterpret_cast<sockaddr_in6*>(ss);
return reinterpret_cast<uint8_t*>(&ss6->sin6_addr);
+ } else if (family == AF_PACKET) {
+ sockaddr_ll* sll = reinterpret_cast<sockaddr_ll*>(ss);
+ return reinterpret_cast<uint8_t*>(&sll->sll_addr);
}
return nullptr;
}
@@ -127,11 +138,21 @@
rtattr* rta = IFLA_RTA(ifi);
size_t rta_len = IFLA_PAYLOAD(hdr);
while (RTA_OK(rta, rta_len)) {
- if (rta->rta_type == IFLA_IFNAME) {
- if (RTA_PAYLOAD(rta) < sizeof(new_addr->name)) {
- memcpy(new_addr->name, RTA_DATA(rta), RTA_PAYLOAD(rta));
- new_addr->ifa.ifa_name = new_addr->name;
- }
+ if (rta->rta_type == IFLA_ADDRESS) {
+ if (RTA_PAYLOAD(rta) < sizeof(new_addr->addr)) {
+ new_addr->SetAddress(AF_PACKET, RTA_DATA(rta), RTA_PAYLOAD(rta));
+ new_addr->SetPacketAttributes(ifi->ifi_index, ifi->ifi_type, RTA_PAYLOAD(rta));
+ }
+ } else if (rta->rta_type == IFLA_BROADCAST) {
+ if (RTA_PAYLOAD(rta) < sizeof(new_addr->ifa_ifu)) {
+ new_addr->SetBroadcastAddress(AF_PACKET, RTA_DATA(rta), RTA_PAYLOAD(rta));
+ new_addr->SetPacketAttributes(ifi->ifi_index, ifi->ifi_type, RTA_PAYLOAD(rta));
+ }
+ } else if (rta->rta_type == IFLA_IFNAME) {
+ if (RTA_PAYLOAD(rta) < sizeof(new_addr->name)) {
+ memcpy(new_addr->name, RTA_DATA(rta), RTA_PAYLOAD(rta));
+ new_addr->ifa.ifa_name = new_addr->name;
+ }
}
rta = RTA_NEXT(rta, rta_len);
}
@@ -139,9 +160,9 @@
ifaddrmsg* msg = reinterpret_cast<ifaddrmsg*>(NLMSG_DATA(hdr));
// We should already know about this from an RTM_NEWLINK message.
- ifaddrs_storage* addr = reinterpret_cast<ifaddrs_storage*>(*out);
+ const ifaddrs_storage* addr = reinterpret_cast<const ifaddrs_storage*>(*out);
while (addr != nullptr && addr->interface_index != static_cast<int>(msg->ifa_index)) {
- addr = reinterpret_cast<ifaddrs_storage*>(addr->ifa.ifa_next);
+ addr = reinterpret_cast<const ifaddrs_storage*>(addr->ifa.ifa_next);
}
// If this is an unknown interface, ignore whatever we're being told about it.
if (addr == nullptr) return;
@@ -161,12 +182,12 @@
while (RTA_OK(rta, rta_len)) {
if (rta->rta_type == IFA_ADDRESS) {
if (msg->ifa_family == AF_INET || msg->ifa_family == AF_INET6) {
- addr->SetAddress(msg->ifa_family, RTA_DATA(rta), RTA_PAYLOAD(rta));
- addr->SetNetmask(msg->ifa_family, msg->ifa_prefixlen);
+ new_addr->SetAddress(msg->ifa_family, RTA_DATA(rta), RTA_PAYLOAD(rta));
+ new_addr->SetNetmask(msg->ifa_family, msg->ifa_prefixlen);
}
} else if (rta->rta_type == IFA_BROADCAST) {
if (msg->ifa_family == AF_INET || msg->ifa_family == AF_INET6) {
- addr->SetBroadcastAddress(msg->ifa_family, RTA_DATA(rta), RTA_PAYLOAD(rta));
+ new_addr->SetBroadcastAddress(msg->ifa_family, RTA_DATA(rta), RTA_PAYLOAD(rta));
}
}
rta = RTA_NEXT(rta, rta_len);
diff --git a/tests/ifaddrs_test.cpp b/tests/ifaddrs_test.cpp
index 67857cb..bbaaec3 100644
--- a/tests/ifaddrs_test.cpp
+++ b/tests/ifaddrs_test.cpp
@@ -18,6 +18,9 @@
#include <ifaddrs.h>
+#include <linux/if_packet.h>
+#include <netinet/in.h>
+
TEST(ifaddrs, freeifaddrs_null) {
freeifaddrs(nullptr);
}
@@ -28,11 +31,33 @@
ASSERT_EQ(0, getifaddrs(&addrs));
ASSERT_TRUE(addrs != nullptr);
- bool saw_loopback = false;
+ // 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) saw_loopback = true;
+ 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;
+ }
}
- ASSERT_TRUE(saw_loopback);
+
+ // 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);
}
