79 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			Go
		
	
	
	
			
		
		
	
	
			79 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			Go
		
	
	
	
| // +build selinux,linux
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| 
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| package selinux
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| 
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| import (
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| 	"syscall"
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| 	"unsafe"
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| )
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| 
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| var _zero uintptr
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| 
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| // Returns a []byte slice if the xattr is set and nil otherwise
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| // Requires path and its attribute as arguments
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| func lgetxattr(path string, attr string) ([]byte, error) {
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| 	var sz int
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| 	pathBytes, err := syscall.BytePtrFromString(path)
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| 	if err != nil {
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| 		return nil, err
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| 	}
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| 	attrBytes, err := syscall.BytePtrFromString(attr)
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| 	if err != nil {
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| 		return nil, err
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| 	}
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| 
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| 	// Start with a 128 length byte array
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| 	sz = 128
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| 	dest := make([]byte, sz)
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| 	destBytes := unsafe.Pointer(&dest[0])
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| 	_sz, _, errno := syscall.Syscall6(syscall.SYS_LGETXATTR, uintptr(unsafe.Pointer(pathBytes)), uintptr(unsafe.Pointer(attrBytes)), uintptr(destBytes), uintptr(len(dest)), 0, 0)
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| 
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| 	switch {
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| 	case errno == syscall.ENODATA:
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| 		return nil, errno
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| 	case errno == syscall.ENOTSUP:
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| 		return nil, errno
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| 	case errno == syscall.ERANGE:
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| 		// 128 byte array might just not be good enough,
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| 		// A dummy buffer is used ``uintptr(0)`` to get real size
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| 		// of the xattrs on disk
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| 		_sz, _, errno = syscall.Syscall6(syscall.SYS_LGETXATTR, uintptr(unsafe.Pointer(pathBytes)), uintptr(unsafe.Pointer(attrBytes)), uintptr(unsafe.Pointer(nil)), uintptr(0), 0, 0)
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| 		sz = int(_sz)
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| 		if sz < 0 {
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| 			return nil, errno
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| 		}
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| 		dest = make([]byte, sz)
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| 		destBytes := unsafe.Pointer(&dest[0])
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| 		_sz, _, errno = syscall.Syscall6(syscall.SYS_LGETXATTR, uintptr(unsafe.Pointer(pathBytes)), uintptr(unsafe.Pointer(attrBytes)), uintptr(destBytes), uintptr(len(dest)), 0, 0)
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| 		if errno != 0 {
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| 			return nil, errno
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| 		}
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| 	case errno != 0:
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| 		return nil, errno
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| 	}
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| 	sz = int(_sz)
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| 	return dest[:sz], nil
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| }
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| 
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| func lsetxattr(path string, attr string, data []byte, flags int) error {
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| 	pathBytes, err := syscall.BytePtrFromString(path)
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| 	if err != nil {
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| 		return err
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| 	}
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| 	attrBytes, err := syscall.BytePtrFromString(attr)
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| 	if err != nil {
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| 		return err
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| 	}
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| 	var dataBytes unsafe.Pointer
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| 	if len(data) > 0 {
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| 		dataBytes = unsafe.Pointer(&data[0])
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| 	} else {
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| 		dataBytes = unsafe.Pointer(&_zero)
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| 	}
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| 	_, _, errno := syscall.Syscall6(syscall.SYS_LSETXATTR, uintptr(unsafe.Pointer(pathBytes)), uintptr(unsafe.Pointer(attrBytes)), uintptr(dataBytes), uintptr(len(data)), uintptr(flags), 0)
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| 	if errno != 0 {
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| 		return errno
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| 	}
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| 	return nil
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| }
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