Description

In remotes/docker/auth/parse.go#L136-L139, empty value of auth-param is treated as error and returned. Rest params are not parsed. However, empty values are valid as defined by

• RFC 7235 section 2.1: auth-param = token BWS "=" BWS ( token / quoted-string )
• RFC 7230 section 3.2.6: quoted-string = DQUOTE *( qdtext / quoted-pair ) DQUOTE

Steps to reproduce the issue

No response

Describe the results you received and expected

Given the Www-Authenticate challenge below

Bearer realm="https://auth.example.io/token",empty="",service="registry.example.io",scope="repository:library/hello-world:pull,push"

Actual:

• realm: https://auth.example.io/token

Expected:

• realm: https://auth.example.io/token
• empty: empty string
• service: registry.example.io
• scope: repository:library/hello-world:pull,push

What version of containerd are you using?

v1.6.0-beta.3

Any other relevant information

No response

Show configuration if it is related to CRI plugin.

No response