smallstep-certificates/kms/azurekms/utils.go
Mariano Cano edd475b81b Allow to configure azurekms using the URI
With an URI, azurekms can be configured with client credentials,
and it can define a default vault and protection level.
2021-10-12 18:24:58 -07:00

99 lines
2.6 KiB
Go

package azurekms
import (
"context"
"crypto"
"encoding/json"
"net/url"
"time"
"github.com/Azure/azure-sdk-for-go/services/keyvault/v7.1/keyvault"
"github.com/pkg/errors"
"github.com/smallstep/certificates/kms/apiv1"
"github.com/smallstep/certificates/kms/uri"
"go.step.sm/crypto/jose"
)
// defaultContext returns the default context used in requests to azure.
func defaultContext() (context.Context, context.CancelFunc) {
return context.WithTimeout(context.Background(), 15*time.Second)
}
// getKeyName returns the uri of the key vault key.
func getKeyName(vault, name string, bundle keyvault.KeyBundle) string {
if bundle.Key != nil && bundle.Key.Kid != nil {
sm := keyIDRegexp.FindAllStringSubmatch(*bundle.Key.Kid, 1)
if len(sm) == 1 && len(sm[0]) == 4 {
m := sm[0]
u := uri.New(Scheme, url.Values{
"vault": []string{m[1]},
"name": []string{m[2]},
})
u.RawQuery = url.Values{"version": []string{m[3]}}.Encode()
return u.String()
}
}
// Fallback to URI without id.
return uri.New(Scheme, url.Values{
"vault": []string{vault},
"name": []string{name},
}).String()
}
// parseKeyName returns the key vault, name and version from URIs like:
//
// - azurekms:vault=key-vault;name=key-name
// - azurekms:vault=key-vault;name=key-name?version=key-id
// - azurekms:vault=key-vault;name=key-name?version=key-id&hsm=true
//
// The key-id defines the version of the key, if it is not passed the latest
// version will be used.
//
// HSM can also be passed to define the protection level if this is not given in
// CreateQuery.
func parseKeyName(rawURI string, defaults DefaultOptions) (vault, name, version string, hsm bool, err error) {
var u *uri.URI
u, err = uri.ParseWithScheme(Scheme, rawURI)
if err != nil {
return
}
if name = u.Get("name"); name == "" {
err = errors.Errorf("key uri %s is not valid: name is missing", rawURI)
return
}
if vault = u.Get("vault"); vault == "" {
if defaults.Vault == "" {
name = ""
err = errors.Errorf("key uri %s is not valid: vault is missing", rawURI)
return
}
vault = defaults.Vault
}
if u.Get("hsm") == "" {
hsm = (defaults.ProtectionLevel == apiv1.HSM)
} else {
hsm = u.GetBool("hsm")
}
version = u.Get("version")
return
}
func vaultBaseURL(vault string) string {
return "https://" + vault + ".vault.azure.net/"
}
func convertKey(key *keyvault.JSONWebKey) (crypto.PublicKey, error) {
b, err := json.Marshal(key)
if err != nil {
return nil, errors.Wrap(err, "error marshaling key")
}
var jwk jose.JSONWebKey
if err := jwk.UnmarshalJSON(b); err != nil {
return nil, errors.Wrap(err, "error unmarshaling key")
}
return jwk.Key, nil
}