1 files changed, 151 insertions, 0 deletions
diff --git a/pkg/sentry/fs/proc/net.go b/pkg/sentry/fs/proc/net.go
new file mode 100644
index 000000000..6e464857a
--- /dev/null
+++ b/pkg/sentry/fs/proc/net.go
@@ -0,0 +1,151 @@
+// Copyright 2018 Google Inc.
+//
+// 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.
+
+package proc
+
+import (
+	"fmt"
+
+	"gvisor.googlesource.com/gvisor/pkg/abi/linux"
+	"gvisor.googlesource.com/gvisor/pkg/sentry/context"
+	"gvisor.googlesource.com/gvisor/pkg/sentry/fs"
+	"gvisor.googlesource.com/gvisor/pkg/sentry/fs/proc/seqfile"
+	"gvisor.googlesource.com/gvisor/pkg/sentry/fs/ramfs"
+	"gvisor.googlesource.com/gvisor/pkg/sentry/inet"
+)
+
+// newNet creates a new proc net entry.
+func (p *proc) newNetDir(ctx context.Context, msrc *fs.MountSource) *fs.Inode {
+	d := &ramfs.Dir{}
+	d.InitDir(ctx, nil, fs.RootOwner, fs.FilePermsFromMode(0555))
+	if s := p.k.NetworkStack(); s != nil && s.SupportsIPv6() {
+		d.AddChild(ctx, "dev", seqfile.NewSeqFileInode(ctx, &netDev{s: s}, msrc))
+		d.AddChild(ctx, "if_inet6", seqfile.NewSeqFileInode(ctx, &ifinet6{s: s}, msrc))
+	}
+	return newFile(d, msrc, fs.SpecialDirectory, nil)
+}
+
+// ifinet6 implements seqfile.SeqSource for /proc/net/if_inet6.
+type ifinet6 struct {
+	s inet.Stack `state:"nosave"` // S/R-FIXME
+}
+
+func (n *ifinet6) contents() []string {
+	var lines []string
+	nics := n.s.Interfaces()
+	for id, naddrs := range n.s.InterfaceAddrs() {
+		nic, ok := nics[id]
+		if !ok {
+			// NIC was added after NICNames was called. We'll just
+			// ignore it.
+			continue
+		}
+
+		for _, a := range naddrs {
+			// IPv6 only.
+			if a.Family != linux.AF_INET6 {
+				continue
+			}
+
+			// Fields:
+			// IPv6 address displayed in 32 hexadecimal chars without colons
+			// Netlink device number (interface index) in hexadecimal (use nic id)
+			// Prefix length in hexadecimal
+			// Scope value (use 0)
+			// Interface flags
+			// Device name
+			lines = append(lines, fmt.Sprintf("%032x %02x %02x %02x %02x %8s\n", a.Addr, id, a.PrefixLen, 0, a.Flags, nic.Name))
+		}
+	}
+	return lines
+}
+
+// NeedsUpdate implements seqfile.SeqSource.NeedsUpdate.
+func (*ifinet6) NeedsUpdate(generation int64) bool {
+	return true
+}
+
+// ReadSeqFileData implements seqfile.SeqSource.ReadSeqFileData.
+func (n *ifinet6) ReadSeqFileData(h seqfile.SeqHandle) ([]seqfile.SeqData, int64) {
+	if h != nil {
+		return nil, 0
+	}
+
+	var data []seqfile.SeqData
+	for _, l := range n.contents() {
+		data = append(data, seqfile.SeqData{Buf: []byte(l), Handle: (*ifinet6)(nil)})
+	}
+
+	return data, 0
+}
+
+// netDev implements seqfile.SeqSource for /proc/net/dev.
+type netDev struct {
+	s inet.Stack `state:"nosave"` // S/R-FIXME
+}
+
+// NeedsUpdate implements seqfile.SeqSource.NeedsUpdate.
+func (n *netDev) NeedsUpdate(generation int64) bool {
+	return true
+}
+
+// ReadSeqFileData implements seqfile.SeqSource.ReadSeqFileData. See Linux's
+// net/core/net-procfs.c:dev_seq_show.
+func (n *netDev) ReadSeqFileData(h seqfile.SeqHandle) ([]seqfile.SeqData, int64) {
+	if h != nil {
+		return nil, 0
+	}
+
+	interfaces := n.s.Interfaces()
+	contents := make([]string, 2, 2+len(interfaces))
+	// Add the table header. From net/core/net-procfs.c:dev_seq_show.
+	contents[0] = "Inter-|   Receive                                                |  Transmit\n"
+	contents[1] = " face |bytes    packets errs drop fifo frame compressed multicast|bytes    packets errs drop fifo colls carrier compressed\n"
+
+	for _, i := range interfaces {
+		// TODO: Collect stats from each inet.Stack
+		// implementation (hostinet, epsocket, and rpcinet).
+
+		// Implements the same format as
+		// net/core/net-procfs.c:dev_seq_printf_stats.
+		l := fmt.Sprintf("%6s: %7d %7d %4d %4d %4d %5d %10d %9d %8d %7d %4d %4d %4d %5d %7d %10d\n",
+			i.Name,
+			// Received
+			0, // bytes
+			0, // packets
+			0, // errors
+			0, // dropped
+			0, // fifo
+			0, // frame
+			0, // compressed
+			0, // multicast
+			// Transmitted
+			0, // bytes
+			0, // packets
+			0, // errors
+			0, // dropped
+			0, // fifo
+			0, // frame
+			0, // compressed
+			0) // multicast
+		contents = append(contents, l)
+	}
+
+	var data []seqfile.SeqData
+	for _, l := range contents {
+		data = append(data, seqfile.SeqData{Buf: []byte(l), Handle: (*ifinet6)(nil)})
+	}
+
+	return data, 0
+}