secrets

Documentation

Overview

Package secrets provides an easy and portable way to encrypt and decrypt messages. Subpackages contain driver implementations of secrets for supported services.

See https://gocloud.dev/howto/secrets/ for a detailed how-to guide.

OpenCensus Integration

OpenCensus supports tracing and metric collection for multiple languages and backend providers. See https://opencensus.io.

This API collects OpenCensus traces and metrics for the following methods:

• Encrypt
• Decrypt

All trace and metric names begin with the package import path. The traces add the method name. For example, "gocloud.dev/secrets/Encrypt". The metrics are "completed_calls", a count of completed method calls by driver, method and status (error code); and "latency", a distribution of method latency by driver and method. For example, "gocloud.dev/secrets/latency".

To enable trace collection in your application, see "Configure Exporter" at https://opencensus.io/quickstart/go/tracing. To enable metric collection in your application, see "Exporting stats" at https://opencensus.io/quickstart/go/metrics.

Example

package main

import (
	"context"
	"fmt"
	"log"

	_ "gocloud.dev/secrets/gcpkms"
	"gocloud.dev/secrets/localsecrets"
)

func main() {
	ctx := context.Background()

	// Construct a *secrets.Keeper from one of the secrets subpackages.
	// This example uses localsecrets.
	sk, err := localsecrets.NewRandomKey()
	if err != nil {
		log.Fatal(err)
	}
	keeper := localsecrets.NewKeeper(sk)
	defer keeper.Close()

	// Now we can use keeper to Encrypt.
	plaintext := []byte("Go CDK Secrets")
	ciphertext, err := keeper.Encrypt(ctx, plaintext)
	if err != nil {
		log.Fatal(err)
	}

	// And/or Decrypt.
	decrypted, err := keeper.Decrypt(ctx, ciphertext)
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(string(decrypted))

}

Output:

Go CDK Secrets

Example (ErrorAs)

package main

import (
	"context"
	"fmt"
	"log"

	"gocloud.dev/secrets"
	_ "gocloud.dev/secrets/gcpkms"
	"google.golang.org/grpc/status"
)

func main() {
	// This example is specific to the gcpkms implementation; it
	// demonstrates access to the underlying google.golang.org/grpc/status.Status
	// type.
	// The types exposed for As by gcpkms are documented in
	// https://godoc.org/gocloud.dev/secrets/gcpkms#hdr-As
	ctx := context.Background()

	const url = "gcpkms://projects/proj/locations/global/keyRings/test/ring/wrongkey"
	keeper, err := secrets.OpenKeeper(ctx, url)
	if err != nil {
		log.Fatal(err)
	}
	defer keeper.Close()

	plaintext := []byte("Go CDK secrets")
	_, err = keeper.Encrypt(ctx, plaintext)
	if err != nil {
		var s *status.Status
		if keeper.ErrorAs(err, &s) {
			fmt.Println(s.Code())
		}
	}
}

Example (OpenFromURL)

package main

import (
	"context"
	"fmt"
	"log"

	"gocloud.dev/secrets"
	_ "gocloud.dev/secrets/localsecrets"
)

func main() {
	ctx := context.Background()

	// Create a Keeper using a URL.
	// This example uses "localsecrets", the in-memory implementation.
	// We need to add a blank import line to register the localsecrets driver's
	// URLOpener, which implements secrets.KeeperURLOpener:
	// import _ "gocloud.dev/secrets/localsecrets"
	// localsecrets registers for the "base64key" scheme.
	// All secrets.OpenKeeper URLs also work with "secrets+" or "secrets+keeper+" prefixes,
	// e.g., "secrets+base64key://..." or "secrets+variable+base64key://...".
	// All secrets URLs also work with the "secrets+" prefix, e.g., "secrets+base64key://".
	k, err := secrets.OpenKeeper(ctx, "base64key://smGbjm71Nxd1Ig5FS0wj9SlbzAIrnolCz9bQQ6uAhl4=")
	if err != nil {
		log.Fatal(err)
	}
	defer k.Close()

	// Now we can use k to encrypt/decrypt.
	plaintext := []byte("Go CDK Secrets")
	ciphertext, err := k.Encrypt(ctx, plaintext)
	if err != nil {
		log.Fatal(err)
	}
	decrypted, err := k.Decrypt(ctx, ciphertext)
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(string(decrypted))

}

Output:

Go CDK Secrets

Index

• Variables
• type Keeper
  • func OpenKeeper(ctx context.Context, urlstr string) (*Keeper, error)
  • func (k *Keeper) Close() error
  • func (k *Keeper) Decrypt(ctx context.Context, ciphertext []byte) (plaintext []byte, err error)
  • func (k *Keeper) Encrypt(ctx context.Context, plaintext []byte) (ciphertext []byte, err error)
  • func (k *Keeper) ErrorAs(err error, i interface{}) bool
• type KeeperURLOpener
• type URLMux
  • func DefaultURLMux() *URLMux
  • func (mux *URLMux) KeeperSchemes() []string
  • func (mux *URLMux) OpenKeeper(ctx context.Context, urlstr string) (*Keeper, error)
  • func (mux *URLMux) OpenKeeperURL(ctx context.Context, u *url.URL) (*Keeper, error)
  • func (mux *URLMux) RegisterKeeper(scheme string, opener KeeperURLOpener)
  • func (mux *URLMux) ValidKeeperScheme(scheme string) bool

Examples

• Package
• Package (ErrorAs)
• Package (OpenFromURL)
• Keeper.Decrypt
• Keeper.Encrypt

Variables

var NewKeeper = newKeeper

NewKeeper is intended for use by drivers only. Do not use in application code.

var (

	// OpenCensusViews are predefined views for OpenCensus metrics.
	// The views include counts and latency distributions for API method calls.
	// See the example at https://godoc.org/go.opencensus.io/stats/view for usage.
	OpenCensusViews = oc.Views(pkgName, latencyMeasure)
)

Types

type Keeper

type Keeper struct {
	// contains filtered or unexported fields
}

Keeper does encryption and decryption. To create a Keeper, use constructors found in driver subpackages.

func OpenKeeper

func OpenKeeper(ctx context.Context, urlstr string) (*Keeper, error)

OpenKeeper opens the Keeper identified by the URL given. See the URLOpener documentation in driver subpackages for details on supported URL formats, and https://gocloud.dev/concepts/urls for more information.

func (*Keeper) Close

func (k *Keeper) Close() error

Close releases any resources used for the Keeper.

func (*Keeper) Decrypt

func (k *Keeper) Decrypt(ctx context.Context, ciphertext []byte) (plaintext []byte, err error)

Decrypt decrypts the ciphertext and returns the plaintext.

Example

package main

import (
	"context"
	"log"

	"gocloud.dev/secrets"
	_ "gocloud.dev/secrets/gcpkms"
)

func main() {
	// PRAGMA: This example is used on gocloud.dev; PRAGMA comments adjust how it is shown and can be ignored.
	// PRAGMA: On gocloud.dev, hide lines until the next blank line.
	ctx := context.Background()
	var keeper *secrets.Keeper

	var cipherText []byte // obtained from elsewhere and random-looking
	plainText, err := keeper.Decrypt(ctx, cipherText)
	if err != nil {
		log.Fatal(err)
	}

	// PRAGMA: On gocloud.dev, hide the rest of the function.
	_ = plainText
}

func (*Keeper) Encrypt

func (k *Keeper) Encrypt(ctx context.Context, plaintext []byte) (ciphertext []byte, err error)

Encrypt encrypts the plaintext and returns the cipher message.

Example

package main

import (
	"context"
	"log"

	"gocloud.dev/secrets"
	_ "gocloud.dev/secrets/gcpkms"
)

func main() {
	// PRAGMA: This example is used on gocloud.dev; PRAGMA comments adjust how it is shown and can be ignored.
	// PRAGMA: On gocloud.dev, hide lines until the next blank line.
	ctx := context.Background()
	var keeper *secrets.Keeper

	plainText := []byte("Secrets secrets...")
	cipherText, err := keeper.Encrypt(ctx, plainText)
	if err != nil {
		log.Fatal(err)
	}

	// PRAGMA: On gocloud.dev, hide the rest of the function.
	_ = cipherText
}

func (*Keeper) ErrorAs

func (k *Keeper) ErrorAs(err error, i interface{}) bool

ErrorAs converts i to driver-specific types. See https://gocloud.dev/concepts/as/ for background information and the driver package documentation for the specific types supported for that driver.

ErrorAs panics if i is nil or not a pointer. ErrorAs returns false if err == nil.

type KeeperURLOpener

type KeeperURLOpener interface {
	OpenKeeperURL(ctx context.Context, u *url.URL) (*Keeper, error)
}

KeeperURLOpener represents types that can open Keepers based on a URL. The opener must not modify the URL argument. OpenKeeperURL must be safe to call from multiple goroutines.

This interface is generally implemented by types in driver packages.

type URLMux

type URLMux struct {
	// contains filtered or unexported fields
}

URLMux is a URL opener multiplexer. It matches the scheme of the URLs against a set of registered schemes and calls the opener that matches the URL's scheme. See https://gocloud.dev/concepts/urls/ for more information.

The zero value is a multiplexer with no registered schemes.

func DefaultURLMux

func DefaultURLMux() *URLMux

DefaultURLMux returns the URLMux used by OpenKeeper.

Driver packages can use this to register their KeeperURLOpener on the mux.

func (*URLMux) KeeperSchemes

func (mux *URLMux) KeeperSchemes() []string

KeeperSchemes returns a sorted slice of the registered Keeper schemes.

func (*URLMux) OpenKeeper

func (mux *URLMux) OpenKeeper(ctx context.Context, urlstr string) (*Keeper, error)

OpenKeeper calls OpenKeeperURL with the URL parsed from urlstr. OpenKeeper is safe to call from multiple goroutines.

func (*URLMux) OpenKeeperURL

func (mux *URLMux) OpenKeeperURL(ctx context.Context, u *url.URL) (*Keeper, error)

OpenKeeperURL dispatches the URL to the opener that is registered with the URL's scheme. OpenKeeperURL is safe to call from multiple goroutines.

func (*URLMux) RegisterKeeper

func (mux *URLMux) RegisterKeeper(scheme string, opener KeeperURLOpener)

RegisterKeeper registers the opener with the given scheme. If an opener already exists for the scheme, RegisterKeeper panics.

func (*URLMux) ValidKeeperScheme

func (mux *URLMux) ValidKeeperScheme(scheme string) bool

ValidKeeperScheme returns true iff scheme has been registered for Keepers.