timestamp.scm

#|
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|#

;; Trusted timestamps
(include "shasum.scm")
(include "query.scm")
(include "reply.scm")
(include "submit.scm")
(include "verify.scm")

;; perform timestamp and return (shasum tsr) list
(define (timestamp-data filename)
  (if (and (file-exists? filename) (eq? (file-type filename) 'regular)
           (fx> (file-info-size (file-info filename)) 0))
    (let* ((csum (sha512sum filename))
           (tsq (timestamp-tsq-generate-sha512sum csum))
           (tsr (timestamp-tsr-request tsq)))
      (if (and tsq tsr (timestamp-tsr-granted? tsr)
            (fx= (timestamp-tsq-getnonce tsq) (timestamp-tsr-getnonce tsr))
            (equal? (timestamp-tsq-getmessage tsq) (timestamp-tsr-getmessage tsr)))
        (list csum tsr) #f)) #f))

;; perform timestamp and save+return tsr
(define (timestamp-gettimestamp filename)
  (let ((res (timestamp-data filename)))
    (if res (if (timestamp-tsr-save filename (cadr res)) (cadr res) #f) #f)))

;; Unit tests
(unit-test "timestamp-gettimestamp" "Requesting a trusted timestamp"
  (lambda () (let* ((filename "LNtest_timestamp")
                    (datalen (random-integer 100000))
                    (data (random-u8vector datalen)))
    (u8vector->file data filename)
    (if (and (timestamp-gettimestamp filename) (file-exists? (string-append filename ".tsr")))
      (begin
        (delete-file filename)
        (delete-file (string-append filename ".tsr"))
        #t
      )
      #f
    )
  )))

(unit-test "timestamp-verify" "Verifying a trusted timestamp"
  (lambda () (let* ((filename "LNtest_timestamp2")
                    (file (u8vector->file (u8vector 76 97 109 98 100 97 78 97 116 105 118 101) filename))
                    (tsr (timestamp-gettimestamp filename))
                    (cafile "cacert.pem"))
    (if (timestamp-verify (sha512sum filename) tsr cafile)
      (begin
        (delete-file filename)
        (delete-file (string-append filename ".tsr"))
        #t
      )
      #f
    )
  )))

;; eof