* guix/nar.scm (restore-file-set)[assert-valid-signature]: Rewrite in
terms of 'signature-case'.
* guix/scripts/substitute-binary.scm (narinfo-signature->canonical-sexp):
Call 'leave' instead of 'raise' when SIGNATURE is invalid.
(&nar-signature-error, &nar-invalid-hash-error): Remove.
(assert-valid-signature): Add 'narinfo' parameter; remove 'port'.
Rewrite in terms of 'signature-case' and 'leave'. Mention NARINFO's
URI in error messages. Adjust caller.
(narinfo-sha256): New procedure.
(assert-valid-narinfo): Use it.
(valid-narinfo?): Rewrite using 'narinfo-sha256' and
'signature-case'.
* tests/substitute-binary.scm (assert-valid-signature,
test-error-condition): Remove.
("corrupt signature data", "unauthorized public key", "invalid
signature"): Remove.
e4687a5e68