lisp/net/dig.el

   1 ;;; dig.el --- Domain Name System dig interface
   2
   3 ;; Copyright (C) 2000, 2001, 2002, 2003, 2004,
   4 ;;   2005, 2006, 2007, 2008 Free Software Foundation, Inc.
   5
   6 ;; Author: Simon Josefsson <simon@josefsson.org>
   7 ;; Keywords: DNS BIND dig
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software; you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published
  13 ;; by the Free Software Foundation; either version 3, or (at your
  14 ;; option) any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful, but
  17 ;; WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19 ;; General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  23 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  24 ;; Boston, MA 02110-1301, USA.
  25
  26 ;;; Commentary:
  27
  28 ;; This provide an interface for "dig".
  29 ;;
  30 ;; For interactive use, try M-x dig and type a hostname.  Use `q' to quit
  31 ;; dig buffer.
  32 ;;
  33 ;; For use in elisp programs, call `dig-invoke' and use
  34 ;; `dig-extract-rr' to extract resource records.
  35
  36 ;;; Release history:
  37
  38 ;; 2000-10-28  posted on gnu.emacs.sources
  39
  40 ;;; Code:
  41
  42 (eval-when-compile (require 'cl))
  43
  44 (defgroup dig nil
  45   "Dig configuration."
  46   :group 'comm)
  47
  48 (defcustom dig-program "dig"
  49   "Name of dig (domain information groper) binary."
  50   :type 'file
  51   :group 'dig)
  52
  53 (defcustom dig-dns-server nil
  54   "DNS server to query.
  55 If nil, use system defaults."
  56   :type '(choice (const :tag "System defaults")
  57                  string)
  58   :group 'dig)
  59
  60 (defcustom dig-font-lock-keywords
  61   '(("^;; [A-Z]+ SECTION:" 0 font-lock-keyword-face)
  62     ("^;;.*" 0 font-lock-comment-face)
  63     ("^; <<>>.*" 0 font-lock-type-face)
  64     ("^;.*" 0 font-lock-function-name-face))
  65   "Default expressions to highlight in dig mode."
  66   :type 'sexp
  67   :group 'dig)
  68
  69 (defun dig-invoke (domain &optional
  70                           query-type query-class query-option
  71                           dig-option server)
  72   "Call dig with given arguments and return buffer containing output.
  73 DOMAIN is a string with a DNS domain. QUERY-TYPE is an optional string
  74 with a DNS type. QUERY-CLASS is an optional string with a DNS class.
  75 QUERY-OPTION is an optional string with dig \"query options\".
  76 DIG-OPTIONS is an optional string with parameters for the dig program.
  77 SERVER is an optional string with a domain name server to query.
  78
  79 Dig is an external program found in the BIND name server distribution,
  80 and is a commonly available debugging tool."
  81   (let (buf cmdline)
  82     (setq buf (generate-new-buffer "*dig output*"))
  83     (if dig-option (push dig-option cmdline))
  84     (if query-option (push query-option cmdline))
  85     (if query-class (push query-class cmdline))
  86     (if query-type (push query-type cmdline))
  87     (push domain cmdline)
  88     (if server (push (concat "@" server) cmdline)
  89       (if dig-dns-server (push (concat "@" dig-dns-server) cmdline)))
  90     (apply 'call-process dig-program nil buf nil cmdline)
  91     buf))
  92
  93 (defun dig-extract-rr (domain &optional type class)
  94   "Extract resource records for DOMAIN, TYPE and CLASS from buffer.
  95 Buffer should contain output generated by `dig-invoke'."
  96   (save-excursion
  97     (goto-char (point-min))
  98     (if (re-search-forward
  99          (concat domain "\\.?[\t ]+[0-9wWdDhHmMsS]+[\t ]+"
 100                  (upcase (or class "IN")) "[\t ]+" (upcase (or type "A")))
 101          nil t)
 102         (let (b e)
 103           (end-of-line)
 104           (setq e (point))
 105           (beginning-of-line)
 106           (setq b (point))
 107           (when (search-forward " (" e t)
 108             (search-forward " )"))
 109           (end-of-line)
 110           (setq e (point))
 111           (buffer-substring b e))
 112       (and (re-search-forward (concat domain "\\.?[\t ]+[0-9wWdDhHmMsS]+[\t ]+"
 113                                       (upcase (or class "IN"))
 114                                       "[\t ]+CNAME[\t ]+\\(.*\\)$") nil t)
 115            (dig-extract-rr (match-string 1) type class)))))
 116
 117 (defun dig-rr-get-pkix-cert (rr)
 118   (let (b e str)
 119     (string-match "[^\t ]+[\t ]+[0-9wWdDhHmMsS]+[\t ]+IN[\t ]+CERT[\t ]+\\(1\\|PKIX\\)[\t ]+[0-9]+[\t ]+[0-9]+[\t ]+(?" rr)
 120     (setq b (match-end 0))
 121     (string-match ")" rr)
 122     (setq e (match-beginning 0))
 123     (setq str (substring rr b e))
 124     (while (string-match "[\t \n\r]" str)
 125       (setq str (replace-match "" nil nil str)))
 126     str))
 127
 128 ;; XEmacs does it like this.  For Emacs, we have to set the
 129 ;; `font-lock-defaults' buffer-local variable.
 130 (put 'dig-mode 'font-lock-defaults '(dig-font-lock-keywords t))
 131
 132 (put 'dig-mode 'mode-class 'special)
 133
 134 (defvar dig-mode-map nil)
 135 (unless dig-mode-map
 136   (setq dig-mode-map (make-sparse-keymap))
 137   (suppress-keymap dig-mode-map)
 138
 139   (define-key dig-mode-map "q" 'dig-exit))
 140
 141 (defun dig-mode ()
 142   "Major mode for displaying dig output."
 143   (interactive)
 144   (kill-all-local-variables)
 145   (setq mode-name "dig")
 146   (setq major-mode 'dig-mode)
 147   (use-local-map dig-mode-map)
 148   (buffer-disable-undo)
 149   (unless (featurep 'xemacs)
 150     (set (make-local-variable 'font-lock-defaults)
 151          '(dig-font-lock-keywords t)))
 152   (when (featurep 'font-lock)
 153     (font-lock-set-defaults))
 154   (save-current-buffer
 155     (if (fboundp 'run-mode-hooks)
 156         (run-mode-hooks 'dig-mode-hook)
 157       (run-hooks 'dig-mode-hook))))
 158
 159 (defun dig-exit ()
 160   "Quit dig output buffer."
 161   (interactive)
 162   (kill-buffer (current-buffer)))
 163
 164 (defun dig (domain &optional
 165                    query-type query-class query-option dig-option server)
 166   "Query addresses of a DOMAIN using dig, by calling `dig-invoke'.
 167 Optional arguments are passed to `dig-invoke'."
 168   (interactive "sHost: ")
 169   (switch-to-buffer
 170    (dig-invoke domain query-type query-class query-option dig-option server))
 171   (goto-char (point-min))
 172   (and (search-forward ";; ANSWER SECTION:" nil t)
 173        (forward-line))
 174   (dig-mode)
 175   (setq buffer-read-only t)
 176   (set-buffer-modified-p nil))
 177
 178 ;; named for consistency with query-dns in dns.el
 179 (defun query-dig (domain &optional
 180                          query-type query-class query-option dig-option server)
 181   "Query addresses of a DOMAIN using dig.
 182 It works by calling `dig-invoke' and `dig-extract-rr'.  Optional
 183 arguments are passed to `dig-invoke' and `dig-extract-rr'.  Returns
 184 nil for domain/class/type queries that results in no data."
 185 (let ((buffer (dig-invoke domain query-type query-class
 186                           query-option dig-option server)))
 187   (when buffer
 188     (switch-to-buffer buffer)
 189     (let ((digger (dig-extract-rr domain query-type query-class)))
 190       (kill-buffer buffer)
 191       digger))))
 192
 193 (provide 'dig)
 194
 195 ;; arch-tag: 1d61726e-9400-4013-9ae7-4035e0c7f7d6
 196 ;;; dig.el ends here