X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?p=userv-utils.git;a=blobdiff_plain;f=www-cgi%2Fucgi.c;h=fc9888b0637529e37696e80fa01f8ffe52b534b4;hp=374fea5c0f1f03eef014f12f2ca649337ba23506;hb=2cbcd670c5dfcda374720737fa5a5cd0be93e338;hpb=6a3086f1860a27894942124c1ecd62502bb4b670

diff --git a/www-cgi/ucgi.c b/www-cgi/ucgi.c
index 374fea5..fc9888b 100644
--- a/www-cgi/ucgi.c
+++ b/www-cgi/ucgi.c
@@ -2,11 +2,16 @@
  * Usage: as CGI script
  */
 /*
- * Copyright (C) 1998-1999,2003 Ian Jackson
+ * Copyright 1996-2013,2016 Ian Jackson <ijackson@chiark.greenend.org.uk>
+ * Copyright 1998 David Damerell <damerell@chiark.greenend.org.uk>
+ * Copyright 1999,2003
+ *    Chancellor Masters and Scholars of the University of Cambridge
+ * Copyright 2010 Tony Finch <fanf@dotat.at>
+ * Copyright 2013,2016 Mark Wooding <mdw@distorted.org.uk>
  *
  * This 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
+ * the Free Software Foundation; either version 3 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful, but
@@ -15,10 +20,7 @@
  * General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
- * along with userv-utils; if not, write to the Free Software
- * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
- * $Id$
+ * along with userv-utils; if not, see http://www.gnu.org/licenses/.
  */
 
 #include <stdio.h>
@@ -30,14 +32,58 @@
 
 #include "ucgi.h"
 
+static const char *const default_envok[] = {
+  "AUTH_TYPE",
+  "CONTENT_TYPE",
+  "CONTENT_LENGTH",
+  "DOCUMENT_ROOT",
+  "GATEWAY_INTERFACE",
+  "HTTP_*",
+  "HTTPS",
+  "PATH_INFO",
+  "PATH_TRANSLATED",
+  "QUERY_STRING",
+  "REDIRECT_*",
+  "REMOTE_*",
+  "REQUEST_METHOD",
+  "REQUEST_URI",
+  "SCRIPT_*",
+  "SERVER_*",
+  "SSL_*",
+  0
+};
+
+struct buildargs {
+  const char **v;
+  int n, max;
+};
+
+static void addarg(struct buildargs *args, const char *a) {
+  if (args->n > args->max) error("too many arguments", 500);
+  args->v[args->n++]= a;
+}
+
+static void add_userv_var(const char *fulln,
+			  const char *en, const char *ev, void *p) {
+  struct buildargs *args= p;
+  size_t l;
+  char *a;
+
+  l= strlen(ev);
+  if (l > MAX_ENVVAR_VALUE) error("environment variable too long", 500);
+  a= xmalloc(strlen(en)+l+6);
+  sprintf(a,"-DE_%s=%s",en,ev);
+  addarg(args, a);
+}
+
 int main(int argc, const char **argv) {
-  char *defarg, *username;
-  const char *slash2, *pathi, *ev, *en, *av;
-  const char *const *ep;
-  const char **arguments;
+  char *username;
+  const char *slash2, *pathi, *ev, *av;
+  const char *const *envok = 0;
   size_t usernamelen, l;
+  struct buildargs args;
   pid_t child, rchild;
-  int nargs, status;
+  int status;
 
   l= strlen(argv[0]);
   if (l>6 && !strcmp(argv[0]+l-6,"-debug")) debugmode= 1;
@@ -49,44 +95,48 @@ int main(int argc, const char **argv) {
     D( printf(";;; UCGI\n"); )
   }
   
-  if (argc > MAX_ARGS) error("too many arguments");
+  if (argc > MAX_ARGS) error("too many arguments", 500);
+
+  ev= getenv("UCGI_ENV_FILTER");
+  if (ev)
+    envok= load_filters(LOADF_MUST, ev, LF_END);
+  else
+    envok= load_filters(0, "/etc/userv/ucgi.env-filter", LF_END);
 
   pathi= getenv("PATH_INFO");
-  if (!pathi) error("PATH_INFO not found");
+  if (!pathi) error("PATH_INFO not found", 500);
   D( if (debugmode) {
        printf(";; find user name...\n"
 	      ";;   initial PATH_INFO = `%s'\n",
 	      pathi);
   } )
-  if (pathi[0] != '/' || pathi[1] != '~') error("PATH_INFO must start with /~");
-  slash2= strchr(pathi+2,'/'); if (!slash2) error("PATH_INFO must have more than one /");
+  if (pathi[0] != '/' || pathi[1] != '~')
+    error("PATH_INFO must start with /~", 400);
+  slash2= strchr(pathi+2,'/');
+  if (!slash2) error("PATH_INFO must have more than one /", 400);
   usernamelen= slash2-(pathi+2);
-  if (usernamelen > MAX_USERNAME_LEN) error("PATH_INFO username too long");
+  if (usernamelen > MAX_USERNAME_LEN) error("PATH_INFO username too long", 400);
   username= xmalloc(usernamelen+1);
   memcpy(username,pathi+2,usernamelen); username[usernamelen]= 0;
   D( if (debugmode)
        printf(";;   user = `%s'; tail = `%s'\n", username, slash2); )
-  if (!isalpha(username[0])) error("username 1st character is not alphabetic");
+  if (!isalpha(username[0]))
+    error("username 1st character is not alphabetic", 400);
   xsetenv("PATH_INFO",slash2,1);
+
+  args.n= 0; args.max= argc + MAX_ENVVARS + 10;
+  args.v= xmalloc(args.max * sizeof(*args.v));
   
-  arguments= xmalloc(sizeof(const char*)*(nenvok+argc+10));
-  nargs= 0;
-  
-  arguments[nargs++]= "userv";
-  if (debugmode) arguments[nargs++]= "-DDEBUG=1";
-  
-  for (ep= envok; (en= *ep); ep++) {
-    ev= getenv(en); if (!ev) continue;
-    l= strlen(ev); if (l > MAX_ENVVAR_VALUE) error("environment variable too long");
-    defarg= xmalloc(strlen(en)+l+6);
-    sprintf(defarg,"-DE_%s=%s",en,ev);
-    arguments[nargs++]= defarg;
-  }
+  addarg(&args, "userv");
+  if (debugmode) addarg(&args, "-DDEBUG=1");
+
+  filter_environment(FILTF_WILDCARD, "", envok, default_envok,
+		     add_userv_var, &args);
 
-  arguments[nargs++]= username;
-  arguments[nargs++]= "www-cgi";
-  while ((av= (*++argv))) arguments[nargs++]= av;
-  arguments[nargs++]= 0;
+  addarg(&args, username);
+  addarg(&args, "www-cgi");
+  while ((av= (*++argv))) addarg(&args, av);
+  addarg(&args, 0);
 
   if (debugmode) {
     D( fflush(stdout); )
@@ -103,12 +153,12 @@ int main(int argc, const char **argv) {
        int i;
 
        printf(";; final command line...\n");
-       for (i = 0; arguments[i]; i++)
-	 printf(";;   %s\n", arguments[i]);
+       for (i = 0; args.v[i]; i++)
+	 printf(";;   %s\n", args.v[i]);
        fflush(stdout);
   } )
 
-  execvp("userv",(char*const*)arguments);
+  execvp("userv",(char*const*)args.v);
   syserror("exec userv");
   return -1;
 }