mirror of
https://git.in.rschanz.org/ryan77627/guix.git
synced 2024-12-25 13:58:15 -05:00
cve: Use 'http-fetch/cached' instead of having custom caching.
That way CVE fetching benefits from 'If-Modified-Since' handling. * guix/http-client.scm (http-fetch/cached): Add #:write-cache and #:cache-miss parameters and honor them. * guix/cve.scm (%current-year-ttl, %past-year-ttl): Reduce. (call-with-cve-port): Remove. (write-cache): New procedure. (fetch-vulnerabilities): Rewrite in terms of 'http-fetch/cached'.
This commit is contained in:
parent
866f37fb7e
commit
7482b98120
2 changed files with 42 additions and 65 deletions
94
guix/cve.scm
94
guix/cve.scm
|
@ -19,7 +19,6 @@
|
|||
(define-module (guix cve)
|
||||
#:use-module (guix utils)
|
||||
#:use-module (guix http-client)
|
||||
#:use-module ((guix build utils) #:select (mkdir-p))
|
||||
#:use-module (sxml ssax)
|
||||
#:use-module (web uri)
|
||||
#:use-module (srfi srfi-1)
|
||||
|
@ -68,24 +67,11 @@ (define (yearly-feed-uri year)
|
|||
(define %current-year-ttl
|
||||
;; According to <https://nvd.nist.gov/download.cfm#CVE_FEED>, feeds are
|
||||
;; updated "approximately every two hours."
|
||||
(* 3600 3))
|
||||
(* 60 30))
|
||||
|
||||
(define %past-year-ttl
|
||||
;; Update the previous year's database more and more infrequently.
|
||||
(* 3600 24 2 (date-month %now)))
|
||||
|
||||
(define (call-with-cve-port uri ttl proc)
|
||||
"Pass PROC an input port from which to read the CVE stream."
|
||||
(let ((port (http-fetch uri)))
|
||||
(dynamic-wind
|
||||
(const #t)
|
||||
(lambda ()
|
||||
(call-with-decompressed-port 'gzip port
|
||||
(lambda (port)
|
||||
(setvbuf port _IOFBF 65536)
|
||||
(proc port))))
|
||||
(lambda ()
|
||||
(close-port port)))))
|
||||
(* 3600 24 (date-month %now)))
|
||||
|
||||
(define %cpe-package-rx
|
||||
;; For applications: "cpe:/a:VENDOR:PACKAGE:VERSION", or sometimes
|
||||
|
@ -194,40 +180,27 @@ (define sexp->vulnerability
|
|||
(('v id (packages ...))
|
||||
(vulnerability id packages))))
|
||||
|
||||
(define (write-cache input cache)
|
||||
"Read vulnerabilities as gzipped XML from INPUT, and write it as a compact
|
||||
sexp to CACHE."
|
||||
(call-with-decompressed-port 'gzip input
|
||||
(lambda (input)
|
||||
;; XXX: The SSAX "error port" is used to send pointless warnings such as
|
||||
;; "warning: Skipping PI". Turn that off.
|
||||
(define vulns
|
||||
(parameterize ((current-ssax-error-port (%make-void-port "w")))
|
||||
(xml->vulnerabilities input)))
|
||||
|
||||
(write `(vulnerabilities
|
||||
1 ;format version
|
||||
,(map vulnerability->sexp vulns))
|
||||
cache))))
|
||||
|
||||
(define (fetch-vulnerabilities year ttl)
|
||||
"Return the list of <vulnerability> for YEAR, assuming the on-disk cache has
|
||||
the given TTL (fetch from the NIST web site when TTL has expired)."
|
||||
;; Note: We used to keep the original XML files in cache but parsing it
|
||||
;; would take typically ~15s for a year of data. Thus, we instead store a
|
||||
;; summarized version thereof as an sexp, which can be parsed in 1s or so.
|
||||
(define cache
|
||||
(string-append (cache-directory) "/cve/" (number->string year)))
|
||||
|
||||
(define (do-fetch)
|
||||
(call-with-cve-port (yearly-feed-uri year) ttl
|
||||
(lambda (port)
|
||||
;; XXX: The SSAX "error port" is used to send pointless warnings such as
|
||||
;; "warning: Skipping PI". Turn that off.
|
||||
(format (current-error-port) "fetching CVE database for ~a...~%" year)
|
||||
(parameterize ((current-ssax-error-port (%make-void-port "w")))
|
||||
(xml->vulnerabilities port)))))
|
||||
|
||||
(define (update-cache)
|
||||
(mkdir-p (dirname cache))
|
||||
(let ((vulns (do-fetch)))
|
||||
(with-atomic-file-output cache
|
||||
(lambda (port)
|
||||
(write `(vulnerabilities
|
||||
1 ;format version
|
||||
,(map vulnerability->sexp vulns))
|
||||
port)))
|
||||
vulns))
|
||||
|
||||
(define (old? file)
|
||||
;; Return true if PORT has passed TTL.
|
||||
(let* ((s (stat file))
|
||||
(now (current-time time-utc)))
|
||||
(< (+ (stat:mtime s) ttl) (time-second now))))
|
||||
(define (cache-miss uri)
|
||||
(format (current-error-port) "fetching CVE database for ~a...~%" year))
|
||||
|
||||
(define (read* port)
|
||||
;; Disable read options to avoid populating the source property weak
|
||||
|
@ -242,17 +215,18 @@ (define (read* port)
|
|||
(lambda ()
|
||||
(read-options options)))))
|
||||
|
||||
(catch 'system-error
|
||||
(lambda ()
|
||||
(if (old? cache)
|
||||
(update-cache)
|
||||
(match (call-with-input-file cache read*)
|
||||
(('vulnerabilities 1 vulns)
|
||||
(map sexp->vulnerability vulns))
|
||||
(x
|
||||
(update-cache)))))
|
||||
(lambda args
|
||||
(update-cache))))
|
||||
;; Note: We used to keep the original XML files in cache but parsing it
|
||||
;; would take typically ~15s for a year of data. Thus, we instead store a
|
||||
;; summarized version thereof as an sexp, which can be parsed in 1s or so.
|
||||
(let* ((port (http-fetch/cached (yearly-feed-uri year)
|
||||
#:ttl ttl
|
||||
#:write-cache write-cache
|
||||
#:cache-miss cache-miss))
|
||||
(sexp (read* port)))
|
||||
(close-port port)
|
||||
(match sexp
|
||||
(('vulnerabilities 1 vulns)
|
||||
(map sexp->vulnerability vulns)))))
|
||||
|
||||
(define (current-vulnerabilities)
|
||||
"Return the current list of Common Vulnerabilities and Exposures (CVE) as
|
||||
|
@ -307,8 +281,4 @@ (define table
|
|||
package table)))
|
||||
|
||||
|
||||
;;; Local Variables:
|
||||
;;; eval: (put 'call-with-cve-port 'scheme-indent-function 2)
|
||||
;;; End:
|
||||
|
||||
;;; cve.scm ends here
|
||||
|
|
|
@ -302,9 +302,15 @@ (define (cache-file-for-uri uri)
|
|||
(base64-encode digest 0 (bytevector-length digest)
|
||||
#f #f base64url-alphabet))))
|
||||
|
||||
(define* (http-fetch/cached uri #:key (ttl (%http-cache-ttl)) text?)
|
||||
(define* (http-fetch/cached uri #:key (ttl (%http-cache-ttl)) text?
|
||||
(write-cache dump-port)
|
||||
(cache-miss (const #t)))
|
||||
"Like 'http-fetch', return an input port, but cache its contents in
|
||||
~/.cache/guix. The cache remains valid for TTL seconds."
|
||||
~/.cache/guix. The cache remains valid for TTL seconds.
|
||||
|
||||
Call WRITE-CACHE with the HTTP input port and the cache output port to write
|
||||
the data to cache. Call CACHE-MISS with URI just before fetching data from
|
||||
URI."
|
||||
(let ((file (cache-file-for-uri uri)))
|
||||
(define (update-cache cache-port)
|
||||
(define cache-time
|
||||
|
@ -327,11 +333,12 @@ (define headers
|
|||
(raise c))))
|
||||
(let ((port (http-fetch uri #:text? text?
|
||||
#:headers headers)))
|
||||
(cache-miss uri)
|
||||
(mkdir-p (dirname file))
|
||||
(when cache-port
|
||||
(close-port cache-port))
|
||||
(with-atomic-file-output file
|
||||
(cut dump-port port <>))
|
||||
(cut write-cache port <>))
|
||||
(close-port port)
|
||||
(open-input-file file))))
|
||||
|
||||
|
|
Loading…
Reference in a new issue