1 files changed, 163 insertions, 0 deletions
diff --git a/test/syscalls/linux/socket_netlink_route_util.cc b/test/syscalls/linux/socket_netlink_route_util.cc
new file mode 100644
index 000000000..53eb3b6b2
--- /dev/null
+++ b/test/syscalls/linux/socket_netlink_route_util.cc
@@ -0,0 +1,163 @@
+// Copyright 2020 The gVisor Authors.
+//
+// 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 "test/syscalls/linux/socket_netlink_route_util.h"
+
+#include <linux/if.h>
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
+
+#include "absl/types/optional.h"
+#include "test/syscalls/linux/socket_netlink_util.h"
+
+namespace gvisor {
+namespace testing {
+namespace {
+
+constexpr uint32_t kSeq = 12345;
+
+}  // namespace
+
+PosixError DumpLinks(
+    const FileDescriptor& fd, uint32_t seq,
+    const std::function<void(const struct nlmsghdr* hdr)>& fn) {
+  struct request {
+    struct nlmsghdr hdr;
+    struct ifinfomsg ifm;
+  };
+
+  struct request req = {};
+  req.hdr.nlmsg_len = sizeof(req);
+  req.hdr.nlmsg_type = RTM_GETLINK;
+  req.hdr.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP;
+  req.hdr.nlmsg_seq = seq;
+  req.ifm.ifi_family = AF_UNSPEC;
+
+  return NetlinkRequestResponse(fd, &req, sizeof(req), fn, false);
+}
+
+PosixErrorOr<std::vector<Link>> DumpLinks() {
+  ASSIGN_OR_RETURN_ERRNO(FileDescriptor fd, NetlinkBoundSocket(NETLINK_ROUTE));
+
+  std::vector<Link> links;
+  RETURN_IF_ERRNO(DumpLinks(fd, kSeq, [&](const struct nlmsghdr* hdr) {
+    if (hdr->nlmsg_type != RTM_NEWLINK ||
+        hdr->nlmsg_len < NLMSG_SPACE(sizeof(struct ifinfomsg))) {
+      return;
+    }
+    const struct ifinfomsg* msg =
+        reinterpret_cast<const struct ifinfomsg*>(NLMSG_DATA(hdr));
+    const auto* rta = FindRtAttr(hdr, msg, IFLA_IFNAME);
+    if (rta == nullptr) {
+      // Ignore links that do not have a name.
+      return;
+    }
+
+    links.emplace_back();
+    links.back().index = msg->ifi_index;
+    links.back().type = msg->ifi_type;
+    links.back().name =
+        std::string(reinterpret_cast<const char*>(RTA_DATA(rta)));
+  }));
+  return links;
+}
+
+PosixErrorOr<absl::optional<Link>> FindLoopbackLink() {
+  ASSIGN_OR_RETURN_ERRNO(auto links, DumpLinks());
+  for (const auto& link : links) {
+    if (link.type == ARPHRD_LOOPBACK) {
+      return absl::optional<Link>(link);
+    }
+  }
+  return absl::optional<Link>();
+}
+
+PosixError LinkAddLocalAddr(int index, int family, int prefixlen,
+                            const void* addr, int addrlen) {
+  ASSIGN_OR_RETURN_ERRNO(FileDescriptor fd, NetlinkBoundSocket(NETLINK_ROUTE));
+
+  struct request {
+    struct nlmsghdr hdr;
+    struct ifaddrmsg ifaddr;
+    char attrbuf[512];
+  };
+
+  struct request req = {};
+  req.hdr.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifaddr));
+  req.hdr.nlmsg_type = RTM_NEWADDR;
+  req.hdr.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
+  req.hdr.nlmsg_seq = kSeq;
+  req.ifaddr.ifa_index = index;
+  req.ifaddr.ifa_family = family;
+  req.ifaddr.ifa_prefixlen = prefixlen;
+
+  struct rtattr* rta = reinterpret_cast<struct rtattr*>(
+      reinterpret_cast<int8_t*>(&req) + NLMSG_ALIGN(req.hdr.nlmsg_len));
+  rta->rta_type = IFA_LOCAL;
+  rta->rta_len = RTA_LENGTH(addrlen);
+  req.hdr.nlmsg_len = NLMSG_ALIGN(req.hdr.nlmsg_len) + RTA_LENGTH(addrlen);
+  memcpy(RTA_DATA(rta), addr, addrlen);
+
+  return NetlinkRequestAckOrError(fd, kSeq, &req, req.hdr.nlmsg_len);
+}
+
+PosixError LinkChangeFlags(int index, unsigned int flags, unsigned int change) {
+  ASSIGN_OR_RETURN_ERRNO(FileDescriptor fd, NetlinkBoundSocket(NETLINK_ROUTE));
+
+  struct request {
+    struct nlmsghdr hdr;
+    struct ifinfomsg ifinfo;
+    char pad[NLMSG_ALIGNTO];
+  };
+
+  struct request req = {};
+  req.hdr.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifinfo));
+  req.hdr.nlmsg_type = RTM_NEWLINK;
+  req.hdr.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
+  req.hdr.nlmsg_seq = kSeq;
+  req.ifinfo.ifi_index = index;
+  req.ifinfo.ifi_flags = flags;
+  req.ifinfo.ifi_change = change;
+
+  return NetlinkRequestAckOrError(fd, kSeq, &req, req.hdr.nlmsg_len);
+}
+
+PosixError LinkSetMacAddr(int index, const void* addr, int addrlen) {
+  ASSIGN_OR_RETURN_ERRNO(FileDescriptor fd, NetlinkBoundSocket(NETLINK_ROUTE));
+
+  struct request {
+    struct nlmsghdr hdr;
+    struct ifinfomsg ifinfo;
+    char attrbuf[512];
+  };
+
+  struct request req = {};
+  req.hdr.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifinfo));
+  req.hdr.nlmsg_type = RTM_NEWLINK;
+  req.hdr.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
+  req.hdr.nlmsg_seq = kSeq;
+  req.ifinfo.ifi_index = index;
+
+  struct rtattr* rta = reinterpret_cast<struct rtattr*>(
+      reinterpret_cast<int8_t*>(&req) + NLMSG_ALIGN(req.hdr.nlmsg_len));
+  rta->rta_type = IFLA_ADDRESS;
+  rta->rta_len = RTA_LENGTH(addrlen);
+  req.hdr.nlmsg_len = NLMSG_ALIGN(req.hdr.nlmsg_len) + RTA_LENGTH(addrlen);
+  memcpy(RTA_DATA(rta), addr, addrlen);
+
+  return NetlinkRequestAckOrError(fd, kSeq, &req, req.hdr.nlmsg_len);
+}
+
+}  // namespace testing
+}  // namespace gvisor