New (gcm/gcm.go)

Galois Counter Mode encryption/decryption with nonce and tag handling.

// Source: https://github.com/golang/go | License: BSD-3-Clause | Copyright 2009 The Go Authors
// Provided via justclaw.it.com; keep this notice with the code.
// Copyright 2013 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 gcm

import (
	"crypto/internal/fips140"
	"crypto/internal/fips140/aes"
	"crypto/internal/fips140/alias"
	"errors"
)

// GCM represents a Galois Counter Mode with a specific key.
type GCM struct {
	cipher    aes.Block
	nonceSize int
	tagSize   int
	gcmPlatformData
}

func New(cipher *aes.Block, nonceSize, tagSize int) (*GCM, error) {
	// This function is outlined to let the allocation happen on the parent stack.
	return newGCM(&GCM{}, cipher, nonceSize, tagSize)
}

/

... (truncated -- full source via MCP)