bug#31337: Unable to use gnuk usb smartcard token on GuixSD

[Nils Gillmann <gillmann@infotropique.org>]

Vagrant Cascadian transcribed 3.3K bytes:
> I've been unable to use my gnuk usb smartcard token with gnupg on
> GuixSD, and it appears this is because scdaemon is built without libusb
> support:
> 
>       $ gpg --card-status
>       gpg: selecting openpgp failed: No such device
>       gpg: OpenPGP card not available: No such device
> 
> Attached is a patch that gets scdaemon working for me and a gnuk...
> 
> Unfortunately, enabling libusb causes one of the tets to hang
> indefinitely:
> 
>       PASS: tests/openpgp/decrypt-session-key.scm
>       Checking unwrapping the encryption.
>           > encsig-2-keys-3 encsig-2-keys-4 <
>       PASS: tests/openpgp/decrypt-unwrap-verify.scm
>       Checking signing with the default hash algorithm
>           >

There should be a test-suite.log in some location in the build chroot,
have you checked that? You might need to build with -K.

> So far, I've only been able to get it to work by disabling the
> tests... so it's obviously not a good idea to enable without further
> troubleshooting.
> 
> Another option might be to use pcsc-lite and ccid, but I had even less
> luck getting that to work.
> 
> 
> live well,
>   vagrant
> 
> 
> diff --git a/gnu/packages/gnupg.scm b/gnu/packages/gnupg.scm
> index f397482ab..0e9e72784 100644
> --- a/gnu/packages/gnupg.scm
> +++ b/gnu/packages/gnupg.scm
> @@ -39,6 +39,7 @@
>    #:use-module (gnu packages curl)
>    #:use-module (gnu packages crypto)
>    #:use-module (gnu packages emacs)
> +  #:use-module (gnu packages libusb)
>    #:use-module (gnu packages openldap)
>    #:use-module (gnu packages perl)
>    #:use-module (gnu packages perl-check)
> @@ -232,6 +233,7 @@ compatible to GNU Pth.")
>         ("libgcrypt" ,libgcrypt)
>         ("libgpg-error" ,libgpg-error)
>         ("libksba" ,libksba)
> +       ("libusb" ,libusb)
>         ("npth" ,npth)
>         ("openldap" ,openldap)
>         ("pcsc-lite" ,pcsc-lite)
> @@ -246,12 +248,17 @@ compatible to GNU Pth.")
>                            "--enable-all-tests")
>        #:phases
>        (modify-phases %standard-phases
> +	;; (delete 'check)
>          (add-before 'configure 'patch-paths
>            (lambda* (#:key inputs #:allow-other-keys)
>              (substitute* "scd/scdaemon.c"
>                (("\"(libpcsclite\\.so[^\"]*)\"" _ name)
>                 (string-append "\"" (assoc-ref inputs "pcsc-lite")
>                                "/lib/" name "\"")))
> +            (substitute* "configure"
> +              (("/usr/include/libusb-1.0")
> +               (string-append (assoc-ref inputs "libusb")
> +                              "/include/libusb-1.0")))
>              #t))
>          (add-after 'build 'patch-scheme-tests
>            (lambda _