;; The Right-Awful Gemini Server
-;;
+;;
+;; This is a gemini server in the spirit of the
+;; scratchy gopher server. Just as for that server,
+;; rags uses runtime evaluation of embedded scheme
+;; expressions to provide dynamically generated content.
+;;
+;; See the readme for details.
(import (chicken io)
+ (chicken irregex)
(chicken port)
(chicken file)
(chicken string)
(chicken process)
(chicken process-context)
(chicken process-context posix)
- matchable srfi-13
+ matchable srfi-13 srfi-1
uri-common tcp6 openssl)
(define-record config
- root-dir host port certfile keyfile uid gid)
+ root-dir port certfile keyfile uid gid)
(define file-types
'(("gmi" "text/gemini" "charset=utf-8")
("txt" "text/plain" "charset=utf-8")
- ("xml" "text/xml" "charset=utf-8")))
+ ("csv" "text/csv" "charset=utf-8")
+ ("html" "text/html" "charset=utf-8")
+ ("xml" "text/xml" "charset=utf-8")
+ ("pdf" "application/pdf")
+ ("zip" "application/zip")
+ ("jpg" "image/jpeg")
+ ("jpeg" "image/jpeg")
+ ("png" "image/png")
+ ("mp3" "audio/mpeg")))
(define (process-request config request-line)
(let ((uri (uri-normalize-path-segments (absolute-uri request-line))))
(fail-permanent "Unsupported scheme."))
((not (uri-host uri))
(fail-permanent "URL lacks host name."))
- ((not (equal? (uri-host uri) (config-host config)))
+ ((not (valid-hostname (uri-host uri)))
+ (fail-permanent "Invalid host name."))
+ ((not (existing-host config uri))
(fail-permanent "Proxy requests forbidden."))
((uri-path-relative? uri)
(fail-permanent "Path must be absolute."))
((not (document-available? config uri))
(fail-permanent "Document not found."))
+ ((and (document-path-directory? config uri)
+ (uri-lacks-trailing-slash? uri))
+ (redirect-permanent (uri-with-trailing-slash uri)))
+ ((document-script? config uri)
+ (serve-script config uri))
(else
(serve-document config uri)))))
(define (fail-permanent reason)
(print "50 " reason "\r"))
+(define (redirect-permanent new-uri)
+ (print "30 " (uri->string new-uri) "\r"))
+
+(define (serve-query prompt)
+ (print "10 " prompt "\r"))
+
+(define (uri-lacks-trailing-slash? uri)
+ (not (string-null? (last (uri-path uri)))))
+
+(define (uri-with-trailing-slash uri)
+ (update-uri uri path: (append (uri-path uri) '(""))))
+
+(define (valid-hostname name)
+ (let*
+ ((host-label-part '(+ (or alphanumeric #\- #\_)))
+ (domain-part `(: #\. ,host-label-part))
+ (hostname-regex `(: ,host-label-part (+ ,domain-part))))
+ (irregex-match? hostname-regex name)))
+
+(define (existing-host config uri)
+ (directory-exists? (make-pathname (config-root-dir config) (uri-host uri))))
+
(define (document-available? config uri)
(file-exists? (document-path config uri)))
+(define (document-script? config uri)
+ (let ((path (document-path config uri)))
+ (and (file-exists? path)
+ (file-executable? path)
+ (equal? (pathname-extension path) "scm"))))
+
+(define (document-path-directory? config uri)
+ (directory-exists? (document-path-raw config uri)))
+
+(define (document-path-raw config uri)
+ (let* ((crumbs (reverse (cons (config-root-dir config)
+ (cons (uri-host uri) (cdr (uri-path uri)))))))
+ (make-pathname (reverse (cdr crumbs)) (car crumbs))))
+
(define (document-path config uri)
- (let* ((crumbs (reverse (cons (config-root-dir config) (cdr (uri-path uri)))))
- (path (make-pathname (reverse (cdr crumbs)) (car crumbs))))
+ (let* ((path (document-path-raw config uri)))
(if (directory-exists? path)
(make-pathname path "index.gmi")
path)))
+
+(define (ext->mime ext)
+ (let* ((mime-detected (assoc ext file-types)))
+ (cdr (if mime-detected
+ mime-detected
+ (assoc "txt" file-types)))))
+
+(define (serve-document-header mime)
+ (print "20 " (string-intersperse mime ";") "\r"))
(define (serve-document config uri)
(let* ((path (document-path config uri))
(ext (pathname-extension path))
- (mime-detected (assoc ext file-types))
- (mime (if mime-detected mime-detected (assoc "txt" file-types)))
- (mime-type (cadr mime)))
- (print "20 " (string-intersperse (cdr mime) ";") "\r")
+ (mime (ext->mime ext)))
+ (serve-document-header mime)
(cond
((file-executable? path)
(serve-text-dynamic path)) ; Binary-files can also be generated here, but the source is dynamic text
- ((string-prefix? "text/" mime-type)
+ ((string-prefix? "text/" (car mime))
(serve-text-plain path))
(else (serve-binary path)))))
(close-output-port out-port))))))
(else (error "Unknown element type."))))
+(define (serve-script config uri)
+ ;; Scripts are responsible for the entire response, including header
+ (let* ((path (document-path config uri))
+ (proc (eval (with-input-from-file path read))))
+ (with-current-working-directory
+ (pathname-directory (document-path config uri))
+ (lambda ()
+ (apply proc (list uri))))))
+
(define (with-current-working-directory directory thunk)
(let ((old-wd (current-directory))
(result 'none))
private-key: (config-keyfile config)
protocol: 'tlsv12))
- (print "Host: '" (config-host config) "'\n"
+ (print
"Port: '" (config-port config) "'\n"
"Root directory: '" (config-root-dir config) "'\n"
"Cert file: '" (config-certfile config) "'\n"
(print "Usage:\n"
progname " [-h/--help]\n"
progname " [-p/--port PORT] [-u/--user UID] [-g/--group GID]\n"
- indent-str " server-root-dir hostname certfile keyfile")))
+ indent-str " server-root-dir certfile keyfile")))
(define (main)
(let* ((progname (pathname-file (car (argv))))
- (config (make-config #f #f 1965 #f #f #f #f)))
- (if (null? (cdr (argv)))
+ (config (make-config #f 1965 #f #f #f #f)))
+ (if (null? (command-line-arguments))
(print-usage progname)
- (let loop ((args (cdr (argv))))
+ (let loop ((args (command-line-arguments)))
(let ((this-arg (car args))
(rest-args (cdr args)))
(if (string-prefix? "-" this-arg)
(else
(print-usage progname)))
(match args
- ((root-dir host certfile keyfile)
+ ((root-dir certfile keyfile)
(config-root-dir-set! config root-dir)
- (config-host-set! config host)
(config-certfile-set! config certfile)
(config-keyfile-set! config keyfile)
(run-server config))
The Lambda Lab / projects / rags.git / blobdiff