mirror of
				https://gitea.com/Lydanne/buildx.git
				synced 2025-11-04 01:53:42 +08:00 
			
		
		
		
	Bump github.com/gogo/googleapis to v1.3.2 Bump github.com/docker/cli to master Signed-off-by: Silvin Lubecki <silvin.lubecki@docker.com>
		
			
				
	
	
		
			90 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			90 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
// Copyright 2012 The Go Authors. All rights reserved.
 | 
						|
// Use of this source code is governed by a BSD-style
 | 
						|
// license that can be found in the LICENSE file.
 | 
						|
 | 
						|
// Package poly1305 implements Poly1305 one-time message authentication code as
 | 
						|
// specified in https://cr.yp.to/mac/poly1305-20050329.pdf.
 | 
						|
//
 | 
						|
// Poly1305 is a fast, one-time authentication function. It is infeasible for an
 | 
						|
// attacker to generate an authenticator for a message without the key. However, a
 | 
						|
// key must only be used for a single message. Authenticating two different
 | 
						|
// messages with the same key allows an attacker to forge authenticators for other
 | 
						|
// messages with the same key.
 | 
						|
//
 | 
						|
// Poly1305 was originally coupled with AES in order to make Poly1305-AES. AES was
 | 
						|
// used with a fixed key in order to generate one-time keys from an nonce.
 | 
						|
// However, in this package AES isn't used and the one-time key is specified
 | 
						|
// directly.
 | 
						|
package poly1305 // import "golang.org/x/crypto/poly1305"
 | 
						|
 | 
						|
import "crypto/subtle"
 | 
						|
 | 
						|
// TagSize is the size, in bytes, of a poly1305 authenticator.
 | 
						|
const TagSize = 16
 | 
						|
 | 
						|
// Sum generates an authenticator for msg using a one-time key and puts the
 | 
						|
// 16-byte result into out. Authenticating two different messages with the same
 | 
						|
// key allows an attacker to forge messages at will.
 | 
						|
func Sum(out *[16]byte, m []byte, key *[32]byte) {
 | 
						|
	sum(out, m, key)
 | 
						|
}
 | 
						|
 | 
						|
// Verify returns true if mac is a valid authenticator for m with the given key.
 | 
						|
func Verify(mac *[16]byte, m []byte, key *[32]byte) bool {
 | 
						|
	var tmp [16]byte
 | 
						|
	Sum(&tmp, m, key)
 | 
						|
	return subtle.ConstantTimeCompare(tmp[:], mac[:]) == 1
 | 
						|
}
 | 
						|
 | 
						|
// New returns a new MAC computing an authentication
 | 
						|
// tag of all data written to it with the given key.
 | 
						|
// This allows writing the message progressively instead
 | 
						|
// of passing it as a single slice. Common users should use
 | 
						|
// the Sum function instead.
 | 
						|
//
 | 
						|
// The key must be unique for each message, as authenticating
 | 
						|
// two different messages with the same key allows an attacker
 | 
						|
// to forge messages at will.
 | 
						|
func New(key *[32]byte) *MAC {
 | 
						|
	return &MAC{
 | 
						|
		mac:       newMAC(key),
 | 
						|
		finalized: false,
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
// MAC is an io.Writer computing an authentication tag
 | 
						|
// of the data written to it.
 | 
						|
//
 | 
						|
// MAC cannot be used like common hash.Hash implementations,
 | 
						|
// because using a poly1305 key twice breaks its security.
 | 
						|
// Therefore writing data to a running MAC after calling
 | 
						|
// Sum causes it to panic.
 | 
						|
type MAC struct {
 | 
						|
	mac // platform-dependent implementation
 | 
						|
 | 
						|
	finalized bool
 | 
						|
}
 | 
						|
 | 
						|
// Size returns the number of bytes Sum will return.
 | 
						|
func (h *MAC) Size() int { return TagSize }
 | 
						|
 | 
						|
// Write adds more data to the running message authentication code.
 | 
						|
// It never returns an error.
 | 
						|
//
 | 
						|
// It must not be called after the first call of Sum.
 | 
						|
func (h *MAC) Write(p []byte) (n int, err error) {
 | 
						|
	if h.finalized {
 | 
						|
		panic("poly1305: write to MAC after Sum")
 | 
						|
	}
 | 
						|
	return h.mac.Write(p)
 | 
						|
}
 | 
						|
 | 
						|
// Sum computes the authenticator of all data written to the
 | 
						|
// message authentication code.
 | 
						|
func (h *MAC) Sum(b []byte) []byte {
 | 
						|
	var mac [TagSize]byte
 | 
						|
	h.mac.Sum(&mac)
 | 
						|
	h.finalized = true
 | 
						|
	return append(b, mac[:]...)
 | 
						|
}
 |