68 lines
1.5 KiB
Go
68 lines
1.5 KiB
Go
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// +build linux
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package libcontainer
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import (
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"fmt"
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"os"
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"strings"
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"github.com/syndtr/gocapability/capability"
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)
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var capabilityMap map[string]capability.Cap
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func init() {
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capabilityMap = make(map[string]capability.Cap)
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last := capability.CAP_LAST_CAP
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// workaround for RHEL6 which has no /proc/sys/kernel/cap_last_cap
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if last == capability.Cap(63) {
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last = capability.CAP_BLOCK_SUSPEND
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}
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for _, cap := range capability.List() {
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if cap > last {
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continue
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}
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capKey := fmt.Sprintf("CAP_%s", strings.ToUpper(cap.String()))
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capabilityMap[capKey] = cap
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}
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}
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func newCapWhitelist(caps []string) (*whitelist, error) {
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l := []capability.Cap{}
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for _, c := range caps {
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v, ok := capabilityMap[c]
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if !ok {
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return nil, fmt.Errorf("unknown capability %q", c)
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}
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l = append(l, v)
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}
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pid, err := capability.NewPid(os.Getpid())
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if err != nil {
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return nil, err
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}
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return &whitelist{
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keep: l,
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pid: pid,
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}, nil
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}
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type whitelist struct {
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pid capability.Capabilities
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keep []capability.Cap
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}
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// dropBoundingSet drops the capability bounding set to those specified in the whitelist.
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func (w *whitelist) dropBoundingSet() error {
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w.pid.Clear(capability.BOUNDS)
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w.pid.Set(capability.BOUNDS, w.keep...)
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return w.pid.Apply(capability.BOUNDS)
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}
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// drop drops all capabilities for the current process except those specified in the whitelist.
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func (w *whitelist) drop() error {
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w.pid.Clear(allCapabilityTypes)
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w.pid.Set(allCapabilityTypes, w.keep...)
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return w.pid.Apply(allCapabilityTypes)
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}
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