go-judge/env/env_linux.go

149 lines
3.4 KiB
Go

package env
import (
"fmt"
"io/ioutil"
"os"
"sync/atomic"
"syscall"
"github.com/criyle/go-judge/env/linuxcontainer"
"github.com/criyle/go-judge/env/pool"
"github.com/criyle/go-sandbox/container"
"github.com/criyle/go-sandbox/pkg/cgroup"
"github.com/criyle/go-sandbox/pkg/forkexec"
"github.com/criyle/go-sandbox/pkg/mount"
)
const (
containerName = "executor_server"
defaultWorkDir = "/w"
containerCredStart = 10000
containerCred = 1000
)
// NewBuilder build a environment builder
func NewBuilder(c Config) (pool.EnvBuilder, error) {
root, err := ioutil.TempDir("", "executorserver")
if err != nil {
return nil, err
}
c.Info("Created tmp dir for container root at:", root)
var mb *mount.Builder
mc, err := readMountConfig(c.MountConf)
if err != nil {
if !os.IsNotExist(err) {
return nil, err
}
c.Info("Mount.yaml(", c.MountConf, ") does not exists, use the default container mount")
mb = getDefaultMount(c.TmpFsParam)
} else {
mb, err = parseMountConfig(mc)
if err != nil {
return nil, err
}
}
m := mb.FilterNotExist().Mounts
c.Info("Created container mount at:", mb)
seccomp, err := readSeccompConf(c.SeccompConf)
if err != nil {
return nil, fmt.Errorf("failed to load seccomp config: %v", err)
}
if seccomp != nil {
c.Info("Load seccomp filter: ", c.SeccompConf)
}
unshareFlags := uintptr(forkexec.UnshareFlags)
if c.NetShare {
unshareFlags ^= syscall.CLONE_NEWNET
}
// use setuid container only if running in root privilege
var credGen container.CredGenerator
if os.Getuid() == 0 {
cred := c.ContainerCredStart
if cred == 0 {
cred = containerCredStart
}
credGen = newCredGen(uint32(cred))
}
hostName := containerName
domainName := containerName
workDir := defaultWorkDir
cUID := containerCred
cGID := containerCred
if mc != nil {
hostName = mc.HostName
domainName = mc.DomainName
workDir = mc.WorkDir
cUID = mc.UID
cGID = mc.GID
}
c.Info("Creating container builder: hostName=", hostName, ", domainName=", domainName, ", workDir=", workDir)
b := &container.Builder{
Root: root,
Mounts: m,
CredGenerator: credGen,
Stderr: os.Stderr,
CloneFlags: unshareFlags,
ExecFile: c.ContainerInitPath,
HostName: hostName,
DomainName: domainName,
WorkDir: workDir,
ContainerUID: cUID,
ContainerGID: cGID,
}
cgb := cgroup.NewBuilder(c.CgroupPrefix).WithCPUAcct().WithMemory().WithPids()
if c.Cpuset != "" {
cgb = cgb.WithCPUSet()
}
if c.EnableCPURate {
cgb = cgb.WithCPU()
}
cgb, err = cgb.FilterByEnv()
if err != nil {
return nil, err
}
c.Info("Test created cgroup builder with:", cgb)
if cg, err := cgb.Build(); err != nil {
c.Warn("Tested created cgroup with error", err)
c.Warn("Failed back to rlimit / rusage mode")
cgb = nil
} else {
cg.Destroy()
}
var cgroupPool linuxcontainer.CgroupPool
if cgb != nil {
cgroupPool = linuxcontainer.NewFakeCgroupPool(cgb, c.CPUCfsPeriod)
}
return linuxcontainer.NewEnvBuilder(linuxcontainer.Config{
Builder: b,
CgroupPool: cgroupPool,
WorkDir: workDir,
Cpuset: c.Cpuset,
CPURate: c.EnableCPURate,
Seccomp: seccomp,
}), nil
}
type credGen struct {
cur uint32
}
func newCredGen(start uint32) *credGen {
return &credGen{cur: start}
}
func (c *credGen) Get() syscall.Credential {
n := atomic.AddUint32(&c.cur, 1)
return syscall.Credential{
Uid: n,
Gid: n,
}
}