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[OpenStack Infra <1872737@xxxxxxxxxxxxxxxxxx>]

Reviewed:  https://review.opendev.org/724124
Committed: https://git.openstack.org/cgit/openstack/keystone/commit/?id=ab89ea749013e7f2c46260f68504f5687763e019
Submitter: Zuul
Branch:    master

commit ab89ea749013e7f2c46260f68504f5687763e019
Author: Colleen Murphy <colleen.murphy@xxxxxxxx>
Date:   Thu Apr 16 17:05:43 2020 -0700

    Check timestamp of signed EC2 token request
    
    EC2 token requests contain a signature that signs the entire request,
    including the access timestamp. While the signature is checked, the
    timestamp is not, and so these signed requests remain valid
    indefinitely, leaving the token API vulnerable to replay attacks. This
    change introduces a configurable TTL for signed token requests and
    ensures that the timestamp is actually validated against it.
    
    The check will work for either an AWS Signature v1/v2 'Timestamp'
    parameter[1] or the AWS Signature v4 'X-Aws-Date' header or
    parameter[2].
    
    Although this technically adds a new feature and the default value of
    the feature changes behavior, this change is required to protect
    credential holders and therefore must be backported to all supported
    branches.
    
    [1] https://docs.aws.amazon.com/general/latest/gr/signature-version-2.html
    [2] https://docs.aws.amazon.com/general/latest/gr/sigv4-date-handling.html
    
    Change-Id: Idb10267338b4204b435df233c636046a1ce5711f
    Closes-bug: #1872737


** Changed in: keystone
       Status: In Progress => Fix Released

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https://bugs.launchpad.net/bugs/1872737

Title:
  Keystone doesn't check signature TTL of the EC2 credential auth method

Status in OpenStack Identity (keystone):
  Fix Released
Status in OpenStack Security Advisory:
  Incomplete

Bug description:
  AWS Signature V4 has a limited TTL for a token signature, used to
  perform an authenticated request, usually it is 5 minutes. If there is
  a MITM possible, then an attacker can use a sniffed header only within
  5 minutes.

  Keystone doesn't have a signature TTL check, and if an attacker can
  sniff an auth header, this header can be used an unlimited number of
  times to reissue an openstack token.

  I have an https://github.com/kayrus/ec2auth tool to auth against
  keystone using ec2 credentials. If you set a timestamp
  (https://godoc.org/github.com/gophercloud/gophercloud/openstack/identity/v3/extensions/ec2tokens#AuthOptions)
  to "time.Time{}" here:
  https://github.com/kayrus/ec2auth/blob/master/pkg/main.go#L40,
  keystone will identify this token as a valid one and return a valid
  openstack token.

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