(* OCaml HTTP - do it yourself (fully OCaml) HTTP daemon Copyright (C) <2002-2004> Stefano Zacchiroli This program 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 2 of the License, or (at your option) any later version. This program 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 this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA *) open Printf;; open Http_common;; open Http_types;; open Http_constants;; open Http_parser;; (** send raw data on outchan, flushing it afterwards *) let send_raw ~data outchan = output_string outchan data; flush outchan let send_CRLF = send_raw ~data:crlf let send_header ~header ~value = Http_parser_sanity.heal_header (header, value); send_raw ~data:(header ^ ": " ^ value ^ crlf) let send_headers ~headers outchan = List.iter (fun (header, value) -> send_header ~header ~value outchan) headers (** internal: low level for send_status_line *) let send_status_line' ~version code = let status_line = String.concat " " [ string_of_version version; string_of_int code; Http_misc.reason_phrase_of_code code ] in send_raw ~data:(status_line ^ crlf) let int_of_code = function | `Code code -> code | `Status status -> code_of_status status let send_status_line ?(version = http_version) ~(code: status_code) outchan = send_status_line' ~version (int_of_code code) outchan (* FIXME duplication of code between this and response#addBasicHeaders *) let send_basic_headers ?(version = http_version) ~(code: status_code) outchan = send_status_line' ~version (int_of_code code) outchan; send_headers ~headers:["Date", Http_misc.date_822 (); "Server", server_string] outchan (** internal: given a status code and an additional body return a string representing an HTML document that explains the meaning of given status code. Additional data can be added to the body via 'body' argument *) let foo_body code body = let reason_phrase = Http_misc.reason_phrase_of_code code in sprintf " %d %s

%d - %s

%s " code reason_phrase code reason_phrase body (** internal: send a fooish body explaining in HTML form the 'reason phrase' of an HTTP response; body, if given, will be appended to the body *) let send_foo_body code body = send_raw ~data:(foo_body code body) (* Warning: keep default values in sync with Http_response.response class *) let respond ?(body = "") ?(headers = []) ?version ?(code = `Code 200) outchan = send_basic_headers ?version ~code outchan; send_headers ~headers outchan; send_header "Content-Length" (string_of_int (String.length body)) outchan; send_CRLF outchan; send_raw ~data:body outchan (** internal: low level for respond_redirect, respond_error, ... This function send a status line corresponding to a given code, some basic headers, the additional headers (if given) and an HTML page containing the reason phrase; if body is given it will be included in the body of the HTML page *) let send_empty_response func_name ?(is_valid_status = fun _ -> true) ?(headers=[]) ?(body="") () = fun ?version code outchan -> if not (is_valid_status (int_of_code code)) then failwith (sprintf "'%d' isn't a valid status code for %s" (int_of_code code) func_name) else begin (* status code suitable for answering *) let headers = [ "Connection", "close"; "Content-Type", "text/html; charset=iso-8859-1" ] @ headers in let body = (foo_body (int_of_code code) body) ^ body in respond ?version ~code ~headers ~body outchan end let respond_redirect ~location ?body ?version ?(code = `Code 301) outchan = send_empty_response "Daemon.respond_redirect" ~is_valid_status:is_redirection ~headers:["Location", location] ?body () ?version code outchan let respond_error ?body ?version ?(code = `Code 400) outchan = send_empty_response "Daemon.respond_error" ~is_valid_status:is_error ?body () ?version code outchan let respond_not_found ~url ?version outchan = send_empty_response "Daemon.respond_not_found" () ?version (`Code 404) outchan let respond_forbidden ~url ?version outchan = send_empty_response "Daemon.respond_permission_denied" () ?version (`Code 403) outchan let respond_unauthorized ?version ?(realm = server_string) outchan = respond ~headers:["WWW-Authenticate", sprintf "Basic realm=\"%s\"" realm] ~code:(`Code 401) outchan let send_file ~src outchan = let buflen = 1024 in let buf = String.make buflen ' ' in let (file, cleanup) = match src with | FileSrc fname -> (* if we open the file, we close it before returning *) let f = open_in fname in f, (fun () -> close_in f) | InChanSrc inchan -> inchan, ignore in try while true do let bytes = input file buf 0 buflen in if bytes = 0 then raise End_of_file else output outchan buf 0 bytes done; assert false with End_of_file -> begin flush outchan; cleanup () end (* TODO interface is too ugly to advertise this function in .mli *) (** create a minimal HTML directory listing of a given directory and send it over an out_channel, directory is passed as a dir_handle; name is the directory name, used for pretty printing purposes; path is the opened dir path, used to test its contents with stat *) let send_dir_listing ~dir ~name ~path outchan = fprintf outchan "\n%s\n\n" name; let (dirs, files) = List.partition (fun e -> Http_misc.is_directory (path ^ e)) (Http_misc.ls dir) in List.iter (fun d -> fprintf outchan "%s/
\n" d d) (List.sort compare dirs); List.iter (fun f -> fprintf outchan "%s
\n" f f) (List.sort compare files); fprintf outchan "\n"; flush outchan let respond_file ~fname ?(version = http_version) outchan = (** ASSUMPTION: 'fname' doesn't begin with a "/"; it's relative to the current document root (usually the daemon's cwd) *) let droot = Sys.getcwd () in (* document root *) let path = droot ^ "/" ^ fname in (* full path to the desired file *) if not (Sys.file_exists path) then (* file not found *) respond_not_found ~url:fname outchan else begin try if Http_misc.is_directory path then begin (* file found, is a dir *) let dir = Unix.opendir path in send_basic_headers ~version ~code:(`Code 200) outchan; send_header "Content-Type" "text/html" outchan; send_CRLF outchan; send_dir_listing ~dir ~name:fname ~path outchan; Unix.closedir dir end else begin (* file found, is something else *) let file = open_in fname in send_basic_headers ~version ~code:(`Code 200) outchan; send_header ~header:"Content-Length" ~value:(string_of_int (Http_misc.filesize fname)) outchan; send_CRLF outchan; send_file ~src:(InChanSrc file) outchan; close_in file end with | Unix.Unix_error (Unix.EACCES, s, _) when (s = fname) -> respond_forbidden ~url:fname ~version outchan | Sys_error s when (Pcre.pmatch ~rex:(Pcre.regexp (fname ^ ": Permission denied")) s) -> respond_forbidden ~url:fname ~version outchan end let respond_with (res: Http_types.response) outchan = res#serialize outchan; flush outchan (** internal: this exception is raised after a malformed request has been read by a serving process to signal main server (or itself if mode = `Single) to skip to next request *) exception Again;; let pp_parse_exc e = sprintf "HTTP request parse error: %s" (Printexc.to_string e) (* given a Http_parser.parse_request like function, wrap it in a function that do the same and additionally catch parsing exception sending HTTP error messages back to client as needed. Returned function raises Again when it encounter a parse error (name 'Again' is intended for future versions that will support http keep alive signaling that a new request has to be parsed from client) *) let rec wrap_parse_request_w_safety parse_function inchan outchan = (* try *) (try parse_function inchan with | (End_of_file) as e -> debug_print (pp_parse_exc e); respond_error ~code:(`Code 400) ~body:"Unexpected End Of File" outchan; raise Again | (Malformed_request req) as e -> debug_print (pp_parse_exc e); respond_error ~code:(`Code 400) ~body:("request 1st line format should be: ' '" ^ "
\nwhile received request 1st line was:
\n" ^ req) outchan; raise Again | (Invalid_HTTP_method meth) as e -> debug_print (pp_parse_exc e); respond_error ~code:(`Code 501) ~body:("Method '" ^ meth ^ "' isn't supported (yet)") outchan; raise Again | (Malformed_request_URI uri) as e -> debug_print (pp_parse_exc e); respond_error ~code:(`Code 400) ~body:("Malformed URL: '" ^ uri ^ "'") outchan; raise Again | (Invalid_HTTP_version version) as e -> debug_print (pp_parse_exc e); respond_error ~code:(`Code 505) ~body:("HTTP version '" ^ version ^ "' isn't supported (yet)") outchan; raise Again | (Malformed_query query) as e -> debug_print (pp_parse_exc e); respond_error ~code:(`Code 400) ~body:(sprintf "Malformed query string '%s'" query) outchan; raise Again | (Malformed_query_part (binding, query)) as e -> debug_print (pp_parse_exc e); respond_error ~code:(`Code 400) ~body:(sprintf "Malformed query part '%s' in query '%s'" binding query) outchan; raise Again) (* (* preliminary support for HTTP keep alive connections ... *) with Again -> wrap_parse_request_w_safety parse_function inchan outchan *) (* wrapper around Http_parser.parse_request which catch parsing exceptions and return error messages to client as needed @param inchan in_channel from which read incoming requests @param outchan out_channl on which respond with error messages if needed *) let safe_parse_request = wrap_parse_request_w_safety parse_request (* as above but for OO version (Http_parser.parse_request') *) let safe_parse_request' = wrap_parse_request_w_safety (new Http_request.request) let chdir_to_document_root = function (* chdir to document root *) | Some dir -> Sys.chdir dir | None -> () let server_of_mode = function | `Single -> Http_tcp_server.simple | `Fork -> Http_tcp_server.fork | `Thread -> Http_tcp_server.thread (* TODO what happens when a Quit exception is raised by a callback? Do other callbacks keep on living until the end or are them all killed immediatly? The right semantics should obviously be the first one *) (* TODO support also chroot to 'root', not only chdir *) (* curried request *) let start ?(addr = default_addr) ?(port = default_port) ?(timeout = Some default_timeout) ?(mode = default_mode) ?root callback = chdir_to_document_root root; let sockaddr = Http_misc.build_sockaddr (addr, port) in let daemon_callback inchan outchan = try let (path, parameters) = safe_parse_request inchan outchan in callback path parameters outchan; flush outchan with | Unauthorized realm -> respond_unauthorized ~realm outchan | Again -> () in try (server_of_mode mode) ~sockaddr ~timeout daemon_callback with Quit -> () (* OO request *) let start' ?(addr = default_addr) ?(port = default_port) ?(timeout = Some default_timeout) ?(mode = default_mode) ?root callback = chdir_to_document_root root; let sockaddr = Http_misc.build_sockaddr (addr, port) in let daemon_callback inchan outchan = try let req = safe_parse_request' inchan outchan in callback req outchan; flush outchan with | Unauthorized realm -> respond_unauthorized ~realm outchan | Again -> () in try (server_of_mode mode) ~sockaddr ~timeout daemon_callback with Quit -> () module Trivial = struct let callback path _ outchan = if not (Pcre.pmatch ~rex:(Pcre.regexp "^/") path) then respond_error ~code:(`Code 400) outchan else respond_file ~fname:(Http_misc.strip_heading_slash path) outchan let start ?(addr = default_addr) ?(port = default_port) () = start ~addr ~port callback end (* @param inchan input channel connected to client @param outchan output channel connected to client @param sockaddr client socket address *) class connection inchan outchan sockaddr = (* ASSUMPTION: inchan and outchan are channels built on top of the same Unix.file_descr thus closing one of them will close also the other *) let close' o = o#close in object (self) initializer Gc.finalise close' self val mutable closed = false method private assertNotClosed = if closed then failwith "Http_daemon.connection: connection is closed" method getRequest = self#assertNotClosed; try Some (safe_parse_request' inchan outchan) with Again -> None method respond_with res = self#assertNotClosed; respond_with res outchan method close = self#assertNotClosed; close_in inchan; (* this close also outchan *) closed <- true end class daemon ?(addr = "0.0.0.0") ?(port = 80) () = object (self) val suck = Http_tcp_server.init_socket (Http_misc.build_sockaddr (addr, port)) method accept = let (cli_suck, cli_sockaddr) = Unix.accept suck in (* may block *) let (inchan, outchan) = (Unix.in_channel_of_descr cli_suck, Unix.out_channel_of_descr cli_suck) in new connection inchan outchan cli_sockaddr method getRequest = let conn = self#accept in match conn#getRequest with | None -> conn#close; self#getRequest | Some req -> (req, conn) end