54 lines
1.2 KiB
Go
54 lines
1.2 KiB
Go
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package users
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import (
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"fmt"
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"os/user"
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"sync"
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)
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// lock is used to serialize all user lookup at the process level, because
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// some NSS implementations are not concurrency safe
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var lock *sync.Mutex
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// nobody is a cached copy of the nobody user, which is going to be looked-up
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// frequently and is unlikely to be modified on the underlying system.
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var nobody user.User
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// Nobody returns User data for the "nobody" user on the system, bypassing the
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// locking / file read / NSS lookup.
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func Nobody() user.User {
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// original is immutable via copy by value
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return nobody
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}
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func init() {
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lock = new(sync.Mutex)
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u, err := Lookup("nobody")
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if err != nil {
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panic(fmt.Sprintf("unable to lookup the nobody user: %v", err))
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}
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nobody = *u
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}
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// Lookup username while holding a global process lock.
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func Lookup(username string) (*user.User, error) {
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lock.Lock()
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defer lock.Unlock()
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return user.Lookup(username)
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}
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// LookupGroupId while holding a global process lock.
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func LookupGroupId(gid string) (*user.Group, error) {
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lock.Lock()
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defer lock.Unlock()
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return user.LookupGroupId(gid)
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}
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// Current returns the current user, acquired while holding a global process
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// lock.
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func Current() (*user.User, error) {
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lock.Lock()
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defer lock.Unlock()
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return user.Current()
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}
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