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Add (guix pki).

* guix/pki.scm, tests/pki.scm: New files.
* Makefile.am (MODULES): Add 'guix/pki.scm'.
  (SCM_TESTS): Add 'tests/pki.scm'.
gn-latest-20200428
Ludovic Courtès 7 years ago
parent
commit
8b420f74e4
3 changed files with 185 additions and 0 deletions
  1. +2
    -0
      Makefile.am
  2. +132
    -0
      guix/pki.scm
  3. +51
    -0
      tests/pki.scm

+ 2
- 0
Makefile.am View File

@@ -31,6 +31,7 @@ MODULES = \
guix/records.scm \
guix/hash.scm \
guix/pk-crypto.scm \
guix/pki.scm \
guix/utils.scm \
guix/download.scm \
guix/monads.scm \
@@ -111,6 +112,7 @@ SCM_TESTS = \
tests/base32.scm \
tests/hash.scm \
tests/pk-crypto.scm \
tests/pki.scm \
tests/builders.scm \
tests/derivations.scm \
tests/ui.scm \


+ 132
- 0
guix/pki.scm View File

@@ -0,0 +1,132 @@
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2013 Ludovic Courtès <ludo@gnu.org>
;;;
;;; This file is part of GNU Guix.
;;;
;;; GNU Guix is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or (at
;;; your option) any later version.
;;;
;;; GNU Guix is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;;; GNU General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.

(define-module (guix pki)
#:use-module (guix config)
#:use-module (guix pk-crypto)
#:use-module ((guix utils) #:select (with-atomic-file-output))
#:use-module (ice-9 match)
#:use-module (rnrs io ports)
#:export (%public-key-file
current-acl
public-keys->acl
acl->public-keys
signature-sexp
authorized-key?))

;;; Commentary:
;;;
;;; Public key infrastructure for the authentication and authorization of
;;; archive imports. This is essentially a subset of SPKI for our own
;;; purposes (see <http://theworld.com/~cme/spki.txt> and
;;; <http://www.ietf.org/rfc/rfc2693.txt>.)
;;;
;;; Code:

(define (acl-entry-sexp public-key)
"Return a SPKI-style ACL entry sexp for PUBLIC-KEY, authorizing imports
signed by the corresponding secret key (see the IETF draft at
<http://theworld.com/~cme/spki.txt> for the ACL format.)"
;; Note: We always use PUBLIC-KEY to designate the subject. Someday we may
;; want to have name certificates and to use subject names instead of
;; complete keys.
(string->canonical-sexp
(format #f
"(entry ~a (tag (guix import)))"
(canonical-sexp->string public-key))))

(define (acl-sexp entries)
"Return an ACL sexp from ENTRIES, a list of 'entry' sexps."
(string->canonical-sexp
(string-append "(acl "
(string-join (map canonical-sexp->string entries))
")")))

(define (public-keys->acl keys)
"Return an ACL canonical sexp that lists all of KEYS with a '(guix import)'
tag---meaning that all of KEYS are authorized for archive imports. Each
element in KEYS must be a canonical sexp with type 'public-key'."
(acl-sexp (map acl-entry-sexp keys)))

(define %acl-file
(string-append %config-directory "/acl"))

(define %public-key-file
(string-append %config-directory "/signing-key.pub"))

(define (ensure-acl)
"Make sure the ACL file exists, and create an initialized one if needed."
(unless (file-exists? %acl-file)
;; If there's no public key file, don't attempt to create the ACL.
(when (file-exists? %public-key-file)
(let ((public-key (call-with-input-file %public-key-file
(compose string->canonical-sexp
get-string-all))))
(with-atomic-file-output %acl-file
(lambda (port)
(display (canonical-sexp->string
(public-keys->acl (list public-key)))
port)))))))

(define (current-acl)
"Return the current ACL as a canonical sexp."
(ensure-acl)
(if (file-exists? %acl-file)
(call-with-input-file %acl-file
(compose string->canonical-sexp
get-string-all))
(public-keys->acl '()))) ; the empty ACL

(define (acl->public-keys acl)
"Return the public keys (as canonical sexps) listed in ACL with the '(guix
import)' tag."
(match (canonical-sexp->sexp acl)
(('acl
('entry subject-keys
('tag ('guix 'import)))
...)
(map sexp->canonical-sexp subject-keys))
(_
(error "invalid access-control list" acl))))

(define* (authorized-key? key
#:optional (acl (current-acl)))
"Return #t if KEY (a canonical sexp) is an authorized public key for archive
imports according to ACL."
(let ((key (canonical-sexp->sexp key)))
(match (canonical-sexp->sexp acl)
(('acl
('entry subject-keys
('tag ('guix 'import)))
...)
(not (not (member key subject-keys))))
(_
(error "invalid access-control list" acl)))))

(define (signature-sexp data secret-key public-key)
"Return a SPKI-style sexp for the signature of DATA with SECRET-KEY that
includes DATA, the actual signature value (with a 'sig-val' tag), and
PUBLIC-KEY (see <http://theworld.com/~cme/spki.txt> for examples.)"
(string->canonical-sexp
(format #f
"(signature ~a ~a ~a)"
(canonical-sexp->string data)
(canonical-sexp->string (sign data secret-key))
(canonical-sexp->string public-key))))

;;; pki.scm ends here

+ 51
- 0
tests/pki.scm View File

@@ -0,0 +1,51 @@
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2013 Ludovic Courtès <ludo@gnu.org>
;;;
;;; This file is part of GNU Guix.
;;;
;;; GNU Guix is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or (at
;;; your option) any later version.
;;;
;;; GNU Guix is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;;; GNU General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.

(define-module (test-pki)
#:use-module (guix pki)
#:use-module (guix pk-crypto)
#:use-module (rnrs io ports)
#:use-module (srfi srfi-64))

;; Test the (guix pki) module.

(define %public-key
(call-with-input-file %public-key-file
(compose string->canonical-sexp
get-string-all)))

(test-begin "pki")

(test-assert "current-acl"
(not (not (member (canonical-sexp->sexp %public-key)
(map canonical-sexp->sexp
(acl->public-keys (current-acl)))))))

(test-assert "authorized-key? public-key current-acl"
(authorized-key? %public-key))

(test-assert "authorized-key? public-key empty-acl"
(not (authorized-key? %public-key (public-keys->acl '()))))

(test-assert "authorized-key? public-key singleton"
(authorized-key? %public-key (public-keys->acl (list %public-key))))

(test-end)

(exit (= (test-runner-fail-count (test-runner-current)) 0))

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