Subversion Repositories wimsdev

/*    Copyright (C) 1998-2003 XIAO, Gang of Universite de Nice - Sophia Antipolis

 *

 *  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., 675 Mass Ave, Cambridge, MA 02139, USA.

 */

 /* This is a small program used simply to fetch web pages.

  * No fancy functionalities such as link redirection or site sucking is

  * present.

  * Page fetched can only be sent to stdout. */

#include <netdb.h>

#include <sys/socket.h>

#include <netinet/in.h>

#include <assert.h>

#include "../includes.h"

#include "../wimsdef.h"

char *cheater1="User-Agent: WIMS-webget";

char *cheater2="Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, image/png, */*\r\n\

Accept-Encoding: gzip\r\n\

Accept-Language: en, fr, it, de, es\r\n\

Accept-Charset: iso-8859-1,*,utf-8";

char pbuf[4096], tbuf[4096];

char tfname[1024];

char *tmpdir="/tmp";

int soc, port, https;

int charcnt;

FILE *outf;

void errorquit(char *msg)

{

    fprintf(stderr,"%s: %s\n",msg,strerror(errno)); exit(1);

}

/* Points to the end of the word */

char *find_word_end(char *p)

{

    int i;

    for(i=0;!isspace(*p) && *p!=0 && i<MAX_LINELEN; p++,i++);

    return p;

}

/* Strips leading spaces */

char *find_word_start(char *p)

{

    int i;

    for(i=0; isspace(*p) && i<MAX_LINELEN; p++,i++);

    return p;

}

/* Secured execution */

void secure(char *host)

{

    char *p1, *p2, *p3, buf[MAX_LINELEN+1];

    long int l;

    FILE *f;

    p1=getenv("w_module"); if(p1==NULL || *p1==0) return;

    p1=getenv("untrust"); if(p1==NULL || *p1==0) return;

    f=fopen("webget.sites","r"); if(f==NULL) return;

    l=fread(buf,1,MAX_LINELEN,f); fclose(f);

    if(l<=0 || l>MAX_LINELEN) return;

    buf[l]=0;

    for(p1=find_word_start(buf);*p1;p1=find_word_start(p2)) {

      p2=find_word_end(p1); if(*p2) *p2++=0;

      p3=strstr(host,p1); if(p3==NULL) continue;

      if((p3==host || *(p3-1)=='.') && *(p3+strlen(p1))==0) return;

    }

    exit(1);  /* unauthorized sites refused. */

}

/* open a TCP/IP socket with host/port

 * returns the file descriptor for the socket */

int net_connect(char *host)

{

    struct hostent *hp;

    struct sockaddr_in sin;

    int soc;

    secure(host);

    if(!(hp = gethostbyname(host))) errorquit("unknown host.");

    if((soc = socket(hp->h_addrtype,SOCK_STREAM,0))<0)

      errorquit("socket() error");

    memmove(&sin.sin_addr,hp->h_addr,hp->h_length);

    sin.sin_port=htons(port);

    sin.sin_family = hp->h_addrtype;

    if(connect(soc,(struct sockaddr *)&sin,sizeof(sin))<0) {

      close(soc); errorquit("connect() error");

    }

    return soc;

}

int gethttps(char *host)

{

    char buf[65536];

    char *tp;

    tp=getenv("tmp_dir"); if(tp!=NULL && *tp!=0) tmpdir=tp;

    snprintf(tfname,sizeof(tfname),"%s/https.tmp",tmpdir);

    snprintf(buf,sizeof(buf),"\

mkdir -p %s\n\

openssl s_client -connect %s:%d -quiet 2>/dev/null >%s <<@\n\

%s\n\

@\n", tmpdir,host,port,tfname,tbuf);

    if (system(buf))

      errorquit("system() error");

    return open(tfname,O_RDONLY);

}

int main(int argc, char *argv[])

{

    char *parm, *pt, *p1, *p2, *p3, *p4, *dp, *pre;

    char nbuf[4096], *pp1, *pp2;

    char c;

    parm=getenv("wims_exec_parm");

    if(parm==NULL || *parm==0) errorquit("no_parameter");

    snprintf(pbuf,sizeof(pbuf),"%s",parm);

    p1=find_word_start(pbuf); p2=find_word_end(p1);

    if(*p2!=0) *p2++=0;

    https=0;

    outf=stdout; pp1=getenv("w_webget_output");

    pp2=getenv("session_dir");

    if(pp1!=NULL && strstr(pp1,"..")==NULL && isalnum(*pp1) && pp2!=NULL) {

      snprintf(nbuf,sizeof(nbuf),"%s/%s",pp2,pp1);

      outf=fopen(nbuf,"w"); if(outf==NULL) outf=stdout;

    }

    dp=getenv("w_webget_option");

    if(dp!=NULL && strstr(dp,"direct")!=NULL) { /* direct get */

      p1=getenv("w_webget_host");

      p2=getenv("w_webget_port");

      if(p1==NULL || p2==NULL) errorquit("incomplete_request");

      port=atoi(p2);

      soc=net_connect(p1); if(soc==-1) return 1;

      c=' '; for(p3=parm; *p3; p3++) {

        if(*p3=='\n' && c!='\r') assert(write(soc,"\r",1)==1);

        assert(write(soc,p3,1)==1);

        c=*p3;

      }

      assert(write(soc,"\r\n\r\n",4)==4);

      pt=getenv("w_module");

      if(pt==NULL || *pt==0 || strncmp(pt,"adm/",4)==0 ) {  /* File to post? */

          pt=getenv("w_webget_post"); if(pt!=NULL && *pt!=0) {

            FILE *f;

            char buf[4096];

            size_t l;

            f=fopen(pt,"r"); if(f!=NULL) {

                do {

                  l=fread(buf,1,sizeof(buf),f);

                  if(l>0 && l<=sizeof(buf)) assert(write(soc,buf,l)==l);

                } while(l==sizeof(buf));

                fclose(f);

            }

          }

      }

      if(strstr(dp,"normalread")!=NULL) goto read;

      charcnt=0;

      while(read(soc,pbuf,1)>0 && charcnt<10240) {

          fputc(pbuf[0],outf); charcnt++;

      }

      close(soc);

      return 0;

    }

    if(strncasecmp(p1,"http://",strlen("http://"))==0) p1+=strlen("http://");

    else if(strncasecmp(p1,"https://",strlen("https://"))==0) {

      https=1; p1+=strlen("https://");

    }

    p3=strchr(p1,'/'); if(p3==NULL) p3="";

    else {*p3++=0; while(*p3=='/') p3++;}

    if(strncasecmp(p3,"http://",strlen("http://"))==0 ||

       strncasecmp(p3,"https://",strlen("https://"))==0) pre="";

    else pre="/";

    snprintf(tbuf,sizeof(tbuf),"GET %s%s HTTP/1.0\r\n%s\r\n\

Host: %s\r\n\

%s\r\n\r\n",

           pre,p3,cheater1,p1,cheater2);

    p4=strchr(p1,':'); if(p4==NULL) {

      if(https) port=443; else port=80;

    }

    else {*p4++=0; port=atoi(p4);}

    if(https) {

      soc=gethttps(p1); goto read;

    }

    soc=net_connect(p1);

    assert(write(soc,tbuf,strlen(tbuf))==strlen(tbuf));

/* header */

    read: if(soc==-1) return 1;

    c=-1;

    while(read(soc,pbuf,1)>0) {

      if(pbuf[0]=='\r') continue;

      fputc(pbuf[0],stderr);

      if((c=='\n') && (pbuf[0]=='\n')) break; else c=pbuf[0];

    }

/* body */

    charcnt=0;

    while(read(soc,pbuf,1)>0 && charcnt<MAX_WEBGETFLEN) {

      fputc(pbuf[0],outf); charcnt++;

    }

    close(soc);

    if(outf!=stdout) fclose(outf);

    if(https) unlink(tfname);

    return 0;

}