diff options
Diffstat (limited to 'pkg/sentry/fsimpl/proc/tasks_sys.go')
| -rw-r--r-- | pkg/sentry/fsimpl/proc/tasks_sys.go | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/pkg/sentry/fsimpl/proc/tasks_sys.go b/pkg/sentry/fsimpl/proc/tasks_sys.go new file mode 100644 index 000000000..aabf2bf0c --- /dev/null +++ b/pkg/sentry/fsimpl/proc/tasks_sys.go @@ -0,0 +1,143 @@ +// Copyright 2019 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. + +package proc + +import ( + "bytes" + "fmt" + + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" +) + +// newSysDir returns the dentry corresponding to /proc/sys directory. +func newSysDir(root *auth.Credentials, inoGen InoGenerator) *kernfs.Dentry { + return kernfs.NewStaticDir(root, inoGen.NextIno(), 0555, map[string]*kernfs.Dentry{ + "kernel": kernfs.NewStaticDir(root, inoGen.NextIno(), 0555, map[string]*kernfs.Dentry{ + "hostname": newDentry(root, inoGen.NextIno(), 0444, &hostnameData{}), + "shmall": newDentry(root, inoGen.NextIno(), 0444, shmData(linux.SHMALL)), + "shmmax": newDentry(root, inoGen.NextIno(), 0444, shmData(linux.SHMMAX)), + "shmmni": newDentry(root, inoGen.NextIno(), 0444, shmData(linux.SHMMNI)), + }), + "vm": kernfs.NewStaticDir(root, inoGen.NextIno(), 0555, map[string]*kernfs.Dentry{ + "mmap_min_addr": newDentry(root, inoGen.NextIno(), 0444, &mmapMinAddrData{}), + "overcommit_memory": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("0\n")), + }), + "net": newSysNetDir(root, inoGen), + }) +} + +// newSysNetDir returns the dentry corresponding to /proc/sys/net directory. +func newSysNetDir(root *auth.Credentials, inoGen InoGenerator) *kernfs.Dentry { + return kernfs.NewStaticDir(root, inoGen.NextIno(), 0555, map[string]*kernfs.Dentry{ + "net": kernfs.NewStaticDir(root, inoGen.NextIno(), 0555, map[string]*kernfs.Dentry{ + "ipv4": kernfs.NewStaticDir(root, inoGen.NextIno(), 0555, map[string]*kernfs.Dentry{ + // Add tcp_sack. + // TODO(gvisor.dev/issue/1195): tcp_sack allows write(2) + // "tcp_sack": newTCPSackInode(ctx, msrc, s), + + // The following files are simple stubs until they are implemented in + // netstack, most of these files are configuration related. We use the + // value closest to the actual netstack behavior or any empty file, all + // of these files will have mode 0444 (read-only for all users). + "ip_local_port_range": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("16000 65535")), + "ip_local_reserved_ports": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("")), + "ipfrag_time": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("30")), + "ip_nonlocal_bind": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("0")), + "ip_no_pmtu_disc": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("1")), + + // tcp_allowed_congestion_control tell the user what they are able to + // do as an unprivledged process so we leave it empty. + "tcp_allowed_congestion_control": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("")), + "tcp_available_congestion_control": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("reno")), + "tcp_congestion_control": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("reno")), + + // Many of the following stub files are features netstack doesn't + // support. The unsupported features return "0" to indicate they are + // disabled. + "tcp_base_mss": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("1280")), + "tcp_dsack": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("0")), + "tcp_early_retrans": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("0")), + "tcp_fack": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("0")), + "tcp_fastopen": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("0")), + "tcp_fastopen_key": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("")), + "tcp_invalid_ratelimit": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("0")), + "tcp_keepalive_intvl": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("0")), + "tcp_keepalive_probes": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("0")), + "tcp_keepalive_time": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("7200")), + "tcp_mtu_probing": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("0")), + "tcp_no_metrics_save": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("1")), + "tcp_probe_interval": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("0")), + "tcp_probe_threshold": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("0")), + "tcp_retries1": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("3")), + "tcp_retries2": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("15")), + "tcp_rfc1337": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("1")), + "tcp_slow_start_after_idle": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("1")), + "tcp_synack_retries": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("5")), + "tcp_syn_retries": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("3")), + "tcp_timestamps": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("1")), + }), + "core": kernfs.NewStaticDir(root, inoGen.NextIno(), 0555, map[string]*kernfs.Dentry{ + "default_qdisc": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("pfifo_fast")), + "message_burst": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("10")), + "message_cost": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("5")), + "optmem_max": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("0")), + "rmem_default": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("212992")), + "rmem_max": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("212992")), + "somaxconn": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("128")), + "wmem_default": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("212992")), + "wmem_max": newDentry(root, inoGen.NextIno(), 0444, newStaticFile("212992")), + }), + }), + }) +} + +// mmapMinAddrData implements vfs.DynamicBytesSource for +// /proc/sys/vm/mmap_min_addr. +// +// +stateify savable +type mmapMinAddrData struct { + kernfs.DynamicBytesFile + + k *kernel.Kernel +} + +var _ dynamicInode = (*mmapMinAddrData)(nil) + +// Generate implements vfs.DynamicBytesSource.Generate. +func (d *mmapMinAddrData) Generate(ctx context.Context, buf *bytes.Buffer) error { + fmt.Fprintf(buf, "%d\n", d.k.Platform.MinUserAddress()) + return nil +} + +// hostnameData implements vfs.DynamicBytesSource for /proc/sys/kernel/hostname. +// +// +stateify savable +type hostnameData struct { + kernfs.DynamicBytesFile +} + +var _ dynamicInode = (*hostnameData)(nil) + +// Generate implements vfs.DynamicBytesSource.Generate. +func (*hostnameData) Generate(ctx context.Context, buf *bytes.Buffer) error { + utsns := kernel.UTSNamespaceFromContext(ctx) + buf.WriteString(utsns.HostName()) + buf.WriteString("\n") + return nil +} |