telebit/vendor/github.com/mholt/acmez/acme/account.go

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2020-11-03 07:56:35 +00:00
// Copyright 2020 Matthew Holt
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package acme
import (
"context"
"crypto"
"encoding/base64"
"encoding/json"
"fmt"
)
// Account represents a set of metadata associated with an account
// as defined by the ACME spec §7.1.2:
// https://tools.ietf.org/html/rfc8555#section-7.1.2
type Account struct {
// status (required, string): The status of this account. Possible
// values are "valid", "deactivated", and "revoked". The value
// "deactivated" should be used to indicate client-initiated
// deactivation whereas "revoked" should be used to indicate server-
// initiated deactivation. See Section 7.1.6.
Status string `json:"status"`
// contact (optional, array of string): An array of URLs that the
// server can use to contact the client for issues related to this
// account. For example, the server may wish to notify the client
// about server-initiated revocation or certificate expiration. For
// information on supported URL schemes, see Section 7.3.
Contact []string `json:"contact,omitempty"`
// termsOfServiceAgreed (optional, boolean): Including this field in a
// newAccount request, with a value of true, indicates the client's
// agreement with the terms of service. This field cannot be updated
// by the client.
TermsOfServiceAgreed bool `json:"termsOfServiceAgreed,omitempty"`
// externalAccountBinding (optional, object): Including this field in a
// newAccount request indicates approval by the holder of an existing
// non-ACME account to bind that account to this ACME account. This
// field is not updateable by the client (see Section 7.3.4).
//
// Use SetExternalAccountBinding() to set this field's value properly.
ExternalAccountBinding json.RawMessage `json:"externalAccountBinding,omitempty"`
// orders (required, string): A URL from which a list of orders
// submitted by this account can be fetched via a POST-as-GET
// request, as described in Section 7.1.2.1.
Orders string `json:"orders"`
// In response to new-account, "the server returns this account
// object in a 201 (Created) response, with the account URL
// in a Location header field." §7.3
//
// We transfer the value from the header to this field for
// storage and recall purposes.
Location string `json:"location,omitempty"`
// The private key to the account. Because it is secret, it is
// not serialized as JSON and must be stored separately (usually
// a PEM-encoded file).
PrivateKey crypto.Signer `json:"-"`
}
// SetExternalAccountBinding sets the ExternalAccountBinding field of the account.
// It only sets the field value; it does not register the account with the CA. (The
// client parameter is necessary because the EAB encoding depends on the directory.)
func (a *Account) SetExternalAccountBinding(ctx context.Context, client *Client, eab EAB) error {
if err := client.provision(ctx); err != nil {
return err
}
macKey, err := base64.RawURLEncoding.DecodeString(eab.MACKey)
if err != nil {
return fmt.Errorf("base64-decoding MAC key: %w", err)
}
eabJWS, err := jwsEncodeEAB(a.PrivateKey.Public(), macKey, keyID(eab.KeyID), client.dir.NewAccount)
if err != nil {
return fmt.Errorf("signing EAB content: %w", err)
}
a.ExternalAccountBinding = eabJWS
return nil
}
// NewAccount creates a new account on the ACME server.
//
// "A client creates a new account with the server by sending a POST
// request to the server's newAccount URL." §7.3
func (c *Client) NewAccount(ctx context.Context, account Account) (Account, error) {
if err := c.provision(ctx); err != nil {
return account, err
}
return c.postAccount(ctx, c.dir.NewAccount, accountObject{Account: account})
}
// GetAccount looks up an account on the ACME server.
//
// "If a client wishes to find the URL for an existing account and does
// not want an account to be created if one does not already exist, then
// it SHOULD do so by sending a POST request to the newAccount URL with
// a JWS whose payload has an 'onlyReturnExisting' field set to 'true'."
// §7.3.1
func (c *Client) GetAccount(ctx context.Context, account Account) (Account, error) {
if err := c.provision(ctx); err != nil {
return account, err
}
return c.postAccount(ctx, c.dir.NewAccount, accountObject{
Account: account,
OnlyReturnExisting: true,
})
}
// UpdateAccount updates account information on the ACME server.
//
// "If the client wishes to update this information in the future, it
// sends a POST request with updated information to the account URL.
// The server MUST ignore any updates to the 'orders' field,
// 'termsOfServiceAgreed' field (see Section 7.3.3), the 'status' field
// (except as allowed by Section 7.3.6), or any other fields it does not
// recognize." §7.3.2
//
// This method uses the account.Location value as the account URL.
func (c *Client) UpdateAccount(ctx context.Context, account Account) (Account, error) {
return c.postAccount(ctx, account.Location, accountObject{Account: account})
}
type keyChangeRequest struct {
Account string `json:"account"`
OldKey json.RawMessage `json:"oldKey"`
}
// AccountKeyRollover changes an account's associated key.
//
// "To change the key associated with an account, the client sends a
// request to the server containing signatures by both the old and new
// keys." §7.3.5
func (c *Client) AccountKeyRollover(ctx context.Context, account Account, newPrivateKey crypto.Signer) (Account, error) {
if err := c.provision(ctx); err != nil {
return account, err
}
oldPublicKeyJWK, err := jwkEncode(account.PrivateKey.Public())
if err != nil {
return account, fmt.Errorf("encoding old private key: %v", err)
}
keyChangeReq := keyChangeRequest{
Account: account.Location,
OldKey: []byte(oldPublicKeyJWK),
}
innerJWS, err := jwsEncodeJSON(keyChangeReq, newPrivateKey, "", "", c.dir.KeyChange)
if err != nil {
return account, fmt.Errorf("encoding inner JWS: %v", err)
}
_, err = c.httpPostJWS(ctx, account.PrivateKey, account.Location, c.dir.KeyChange, json.RawMessage(innerJWS), nil)
if err != nil {
return account, fmt.Errorf("rolling key on server: %w", err)
}
account.PrivateKey = newPrivateKey
return account, nil
}
func (c *Client) postAccount(ctx context.Context, endpoint string, account accountObject) (Account, error) {
// Normally, the account URL is the key ID ("kid")... except when the user
// is trying to get the correct account URL. In that case, we must ignore
// any existing URL we may have and not set the kid field on the request.
// Arguably, this is a user error (spec says "If client wishes to find the
// URL for an existing account", so why would the URL already be filled
// out?) but it's easy enough to infer their intent and make it work.
kid := account.Location
if account.OnlyReturnExisting {
kid = ""
}
resp, err := c.httpPostJWS(ctx, account.PrivateKey, kid, endpoint, account, &account.Account)
if err != nil {
return account.Account, err
}
account.Location = resp.Header.Get("Location")
return account.Account, nil
}
type accountObject struct {
Account
// If true, newAccount will be read-only, and Account.Location
// (which holds the account URL) must be empty.
OnlyReturnExisting bool `json:"onlyReturnExisting,omitempty"`
}
// EAB (External Account Binding) contains information
// necessary to bind or map an ACME account to some
// other account known by the CA.
//
// External account bindings are "used to associate an
// ACME account with an existing account in a non-ACME
// system, such as a CA customer database."
//
// "To enable ACME account binding, the CA operating the
// ACME server needs to provide the ACME client with a
// MAC key and a key identifier, using some mechanism
// outside of ACME." §7.3.4
type EAB struct {
// "The key identifier MUST be an ASCII string." §7.3.4
KeyID string `json:"key_id"`
// "The MAC key SHOULD be provided in base64url-encoded
// form, to maximize compatibility between non-ACME
// provisioning systems and ACME clients." §7.3.4
MACKey string `json:"mac_key"`
}
// Possible status values. From several spec sections:
// - Account §7.1.2 (valid, deactivated, revoked)
// - Order §7.1.3 (pending, ready, processing, valid, invalid)
// - Authorization §7.1.4 (pending, valid, invalid, deactivated, expired, revoked)
// - Challenge §7.1.5 (pending, processing, valid, invalid)
// - Status changes §7.1.6
const (
StatusPending = "pending"
StatusProcessing = "processing"
StatusValid = "valid"
StatusInvalid = "invalid"
StatusDeactivated = "deactivated"
StatusExpired = "expired"
StatusRevoked = "revoked"
StatusReady = "ready"
)