-// Generate and verify permission signatures for Keep locators.
+// Copyright (C) The Arvados Authors. All rights reserved.
//
-// See https://dev.arvados.org/projects/arvados/wiki/Keep_locator_format
+// SPDX-License-Identifier: Apache-2.0
package keepclient
-import (
- "crypto/hmac"
- "crypto/sha1"
- "errors"
- "fmt"
- "regexp"
- "strconv"
- "strings"
- "time"
-)
+import "git.arvados.org/arvados.git/sdk/go/arvados"
var (
- // ErrSignatureExpired - a signature was rejected because the
- // expiry time has passed.
- ErrSignatureExpired = errors.New("Signature expired")
- // ErrSignatureInvalid - a signature was rejected because it
- // was badly formatted or did not match the given secret key.
- ErrSignatureInvalid = errors.New("Invalid signature")
- // ErrSignatureMissing - the given locator does not have a
- // signature hint.
- ErrSignatureMissing = errors.New("Missing signature")
+ ErrSignatureExpired = arvados.ErrSignatureExpired
+ ErrSignatureInvalid = arvados.ErrSignatureInvalid
+ ErrSignatureMissing = arvados.ErrSignatureMissing
+ SignLocator = arvados.SignLocator
+ SignedLocatorRe = arvados.SignedLocatorRe
+ VerifySignature = arvados.VerifySignature
)
-
-// makePermSignature generates a SHA-1 HMAC digest for the given blob,
-// token, expiry, and site secret.
-func makePermSignature(blobHash, apiToken, expiry string, permissionSecret []byte) string {
- hmac := hmac.New(sha1.New, permissionSecret)
- hmac.Write([]byte(blobHash))
- hmac.Write([]byte("@"))
- hmac.Write([]byte(apiToken))
- hmac.Write([]byte("@"))
- hmac.Write([]byte(expiry))
- digest := hmac.Sum(nil)
- return fmt.Sprintf("%x", digest)
-}
-
-// SignLocator returns blobLocator with a permission signature
-// added. If either permissionSecret or apiToken is empty, blobLocator
-// is returned untouched.
-//
-// This function is intended to be used by system components and admin
-// utilities: userland programs do not know the permissionSecret.
-func SignLocator(blobLocator, apiToken string, expiry time.Time, permissionSecret []byte) string {
- if len(permissionSecret) == 0 || apiToken == "" {
- return blobLocator
- }
- // Strip off all hints: only the hash is used to sign.
- blobHash := strings.Split(blobLocator, "+")[0]
- timestampHex := fmt.Sprintf("%08x", expiry.Unix())
- return blobLocator +
- "+A" + makePermSignature(blobHash, apiToken, timestampHex, permissionSecret) +
- "@" + timestampHex
-}
-
-var signedLocatorRe = regexp.MustCompile(`^([[:xdigit:]]{32}).*\+A([[:xdigit:]]{40})@([[:xdigit:]]{8})`)
-
-// VerifySignature returns nil if the signature on the signedLocator
-// can be verified using the given apiToken. Otherwise it returns
-// ErrSignatureExpired (if the signature's expiry time has passed,
-// which is something the client could have figured out
-// independently), ErrSignatureMissing (if there is no signature hint
-// at all), or ErrSignatureInvalid (if the signature is present but
-// badly formatted or incorrect).
-//
-// This function is intended to be used by system components and admin
-// utilities: userland programs do not know the permissionSecret.
-func VerifySignature(signedLocator, apiToken string, permissionSecret []byte) error {
- matches := signedLocatorRe.FindStringSubmatch(signedLocator)
- if matches == nil {
- return ErrSignatureMissing
- }
- blobHash := matches[1]
- signatureHex := matches[2]
- expiryHex := matches[3]
- if expiryTime, err := parseHexTimestamp(expiryHex); err != nil {
- return ErrSignatureInvalid
- } else if expiryTime.Before(time.Now()) {
- return ErrSignatureExpired
- }
- if signatureHex != makePermSignature(blobHash, apiToken, expiryHex, permissionSecret) {
- return ErrSignatureInvalid
- }
- return nil
-}
-
-func parseHexTimestamp(timestampHex string) (ts time.Time, err error) {
- if tsInt, e := strconv.ParseInt(timestampHex, 16, 0); e == nil {
- ts = time.Unix(tsInt, 0)
- } else {
- err = e
- }
- return ts, err
-}
projects / arvados.git / blobdiff