mdw@git.distorted.org.uk Git - userv-utils/blob - www-cgi/ucgi.c

   1 /*
   2  * Usage: as CGI script
   3  */
   4 /*
   5  * Copyright (C) 1998-1999,2003 Ian Jackson
   6  *
   7  * This is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with userv-utils; if not, write to the Free Software
  19  * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  20  *
  21  * $Id$
  22  */
  23
  24 #include <stdio.h>
  25 #include <string.h>
  26 #include <ctype.h>
  27 #include <unistd.h>
  28 #include <sys/types.h>
  29 #include <sys/wait.h>
  30
  31 #include "ucgi.h"
  32
  33 static const char *const envok[] = {
  34   "AUTH_TYPE",
  35   "CONTENT_TYPE",
  36   "CONTENT_LENGTH",
  37   "DOCUMENT_ROOT",
  38   "GATEWAY_INTERFACE",
  39   "HTTP_*",
  40   "HTTPS",
  41   "PATH_INFO",
  42   "PATH_TRANSLATED",
  43   "QUERY_STRING",
  44   "REMOTE_*",
  45   "REQUEST_METHOD",
  46   "REQUEST_URI",
  47   "SCRIPT_*",
  48   "SERVER_*",
  49   0
  50 };
  51
  52 struct buildargs {
  53   const char **v;
  54   int n, max;
  55 };
  56
  57 static void addarg(struct buildargs *args, const char *a) {
  58   if (args->n > args->max) error("too many arguments");
  59   args->v[args->n++]= a;
  60 }
  61
  62 static void add_userv_var(const char *fulln,
  63                           const char *en, const char *ev, void *p) {
  64   struct buildargs *args= p;
  65   size_t l;
  66   char *a;
  67
  68   l= strlen(ev); if (l > MAX_ENVVAR_VALUE) error("environment variable too long");
  69   a= xmalloc(strlen(en)+l+6);
  70   sprintf(a,"-DE_%s=%s",en,ev);
  71   addarg(args, a);
  72 }
  73
  74 int main(int argc, const char **argv) {
  75   char *username;
  76   const char *slash2, *pathi, *av;
  77   size_t usernamelen, l;
  78   struct buildargs args;
  79   pid_t child, rchild;
  80   int status;
  81
  82   l= strlen(argv[0]);
  83   if (l>6 && !strcmp(argv[0]+l-6,"-debug")) debugmode= 1;
  84
  85   if (debugmode) {
  86     if (fputs("Content-Type: text/plain\n\n",stdout)==EOF || fflush(stdout))
  87       syserror("write stdout");
  88     if (dup2(1,2)<0) { perror("dup stdout to stderr"); exit(-1); }
  89     D( printf(";;; UCGI\n"); )
  90   }
  91
  92   if (argc > MAX_ARGS) error("too many arguments");
  93
  94   pathi= getenv("PATH_INFO");
  95   if (!pathi) error("PATH_INFO not found");
  96   D( if (debugmode) {
  97        printf(";; find user name...\n"
  98               ";;   initial PATH_INFO = `%s'\n",
  99               pathi);
 100   } )
 101   if (pathi[0] != '/' || pathi[1] != '~') error("PATH_INFO must start with /~");
 102   slash2= strchr(pathi+2,'/'); if (!slash2) error("PATH_INFO must have more than one /");
 103   usernamelen= slash2-(pathi+2);
 104   if (usernamelen > MAX_USERNAME_LEN) error("PATH_INFO username too long");
 105   username= xmalloc(usernamelen+1);
 106   memcpy(username,pathi+2,usernamelen); username[usernamelen]= 0;
 107   D( if (debugmode)
 108        printf(";;   user = `%s'; tail = `%s'\n", username, slash2); )
 109   if (!isalpha(username[0])) error("username 1st character is not alphabetic");
 110   xsetenv("PATH_INFO",slash2,1);
 111
 112   args.n= 0; args.max= argc + MAX_ENVVARS + 10;
 113   args.v= xmalloc(args.max * sizeof(*args.v));
 114
 115   addarg(&args, "userv");
 116   if (debugmode) addarg(&args, "-DDEBUG=1");
 117
 118   filter_environment(FILTF_WILDCARD, "", envok, add_userv_var, &args);
 119
 120   addarg(&args, username);
 121   addarg(&args, "www-cgi");
 122   while ((av= (*++argv))) addarg(&args, av);
 123   addarg(&args, 0);
 124
 125   if (debugmode) {
 126     D( fflush(stdout); )
 127     child= fork(); if (child==-1) syserror("fork");
 128     if (child) {
 129       rchild= waitpid(child,&status,0);
 130       if (rchild==-1) syserror("waitpid");
 131       printf("\nexit status %d %d\n",(status>>8)&0x0ff,status&0x0ff);
 132       exit(0);
 133     }
 134   }
 135
 136   D( if (debugmode) {
 137        int i;
 138
 139        printf(";; final command line...\n");
 140        for (i = 0; args.v[i]; i++)
 141          printf(";;   %s\n", args.v[i]);
 142        fflush(stdout);
 143   } )
 144
 145   execvp("userv",(char*const*)args.v);
 146   syserror("exec userv");
 147   return -1;
 148 }