/* 
   Unix SMB/Netbios implementation.
   Version 3.0
   MSDfs services for Samba
   Copyright (C) Shirish Kalele 2000

   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.
*/

#include "includes.h"

extern int DEBUGLEVEL;
extern pstring global_myname;
extern global_client_caps;

#ifdef MS_DFS

#define VERSION2_REFERRAL_SIZE 0x16
#define VERSION3_REFERRAL_SIZE 0x22
#define REFERRAL_HEADER_SIZE 0x08

struct dfs_path
{
  pstring hostname;
  pstring servicename;
  pstring volumename;
  pstring restofthepath;
};

void create_nondfs_path(char* pathname, struct dfs_path* pdp)
{
  pstrcpy(pathname,pdp->volumename); 
  pstrcat(pathname,"\\"); 
  pstrcat(pathname,pdp->restofthepath); 
}

/* Parse the pathname  of the form \hostname\service\volume\restofthepath
   into the dfs_path structure */
BOOL parse_dfs_path(char* pathname, struct dfs_path* pdp)
{
  pstring pathname_local;
  char* p,*temp;

  pstrcpy(pathname_local,pathname);
  p = temp = pathname_local;

  ZERO_STRUCTP(pdp);

  /* strip off all \'s from the beginning */
  /* while(*temp=='\\') temp++;
  
  DEBUG(10,("temp in parse_dfs_path : .%s.\n",temp));

   remove any trailing \'s 
  if(temp[strlen(temp)-1] == '\\') temp[strlen(temp)-1]='\0';
*/

  trim_string(temp,"\\","\\");
  DEBUG(10,("temp in parse_dfs_path: .%s. after trimming \'s\n",temp));

  /* now tokenize */
  /* parse out hostname */
  p = strchr(temp,'\\');
  if(p == NULL)
    return False;
  *p = '\0';
  pstrcpy(pdp->hostname,temp);
  DEBUG(10,("hostname: %s\n",pdp->hostname));

  /* parse out servicename */
  temp = p+1;
  p = strchr(temp,'\\');
  if(p == NULL)
    {
      pstrcpy(pdp->servicename,temp);
      return True;
    }
  *p = '\0';
  pstrcpy(pdp->servicename,temp);
  DEBUG(10,("servicename: %s\n",pdp->servicename));

  /* parse out volumename */
  temp = p+1;
  p = strchr(temp,'\\');
  if(p == NULL)
    {
      pstrcpy(pdp->volumename,temp);
      return True;
    }
  *p = '\0';
  pstrcpy(pdp->volumename,temp);
  DEBUG(10,("volumename: %s\n",pdp->volumename));

  /* remaining path .. */
  pstrcpy(pdp->restofthepath,p+1);
  DEBUG(10,("rest of the path: %s\n",pdp->restofthepath));
  return True;
}


/**************************************************************
Decides if given pathname is Dfs and if it should be redirected
Converts pathname to non-dfs format if Dfs redirection not required 
**************************************************************/
BOOL dfs_redirect(char* pathname, connection_struct* conn)
{
  struct dfs_path dp;
  pstring temp;

  pstrcpy(temp,pathname);

  if(lp_dfsmap(SNUM(conn))==NULL || *lp_dfsmap(SNUM(conn))=='\0')
    return False;

  parse_dfs_path(pathname,&dp);

  if(global_myname && (strcasecmp(global_myname,dp.hostname)!=0))
     return False;

  /* check if need to redirect */
  if(isDfsShare(dp.servicename,dp.volumename))
    {
      DEBUG(4,("dfs_redirect: Redirecting %s\n",temp));
      return True;
    }
  else
    {
      create_nondfs_path(pathname,&dp);
      DEBUG(4,("dfs_redirect: Not redirecting %s. Converted to non-dfs pathname \'%s\'\n",
	       temp,pathname));
      return False;
    }
}

/*
  Special DFS redirect call for findfirst's. 
  If the findfirst is for the dfs junction, then no redirection,
  if it is for the underlying directory contents, redirect.
  */
BOOL dfs_findfirst_redirect(char* pathname, connection_struct* conn)
{
  struct dfs_path dp;
  
  pstring temp;

  pstrcpy(temp,pathname);

  /* Is the path Dfs-redirectable? */
  if(!dfs_redirect(temp,conn))
    {
      pstrcpy(pathname,temp);
      return False;
    }

  parse_dfs_path(pathname,&dp);
  DEBUG(8,("dfs_findfirst_redirect: path %s is in Dfs. dp.restofthepath=.%s.\n",pathname,dp.restofthepath));
  if(*(dp.restofthepath))
    return True;
  else
    {
      create_nondfs_path(pathname,&dp);
      return False;
    }
}

/******************************************************************
 * Set up the Dfs referral for the dfs pathname
 ******************************************************************/
int setup_dfs_referral(char* pathname, int max_referral_level, 
			char** ppdata)
{
  struct dfs_path dp;
  
  struct junction_map junction;

  BOOL self_referral;

  char* pdata = *ppdata;
  int reply_size = 0;

  ZERO_STRUCT(junction);

  parse_dfs_path(pathname,&dp);

  /* check if path is dfs : check hostname is the first token */
  if(global_myname && (strcasecmp(global_myname,dp.hostname)!=0))
     {
       DEBUG(4,("Invalid DFS referral request for %s\n",pathname));
       return -1;
     }

  /* Check for a non-DFS share */
  {
    char* map = lp_dfsmap(lp_servicenumber(dp.servicename));
    DEBUG(10,("lp_dfsmap in setup dfs referral: .%s.\n",map ));
    
    if(map == NULL | *map == '\0')
      return -1;
  }

  pstrcpy(junction.service_name,dp.servicename);
  pstrcpy(junction.volume_name,dp.volumename);

  /* get the junction entry */
  if(!get_junction_entry(&junction))
    {
      
      /* refer the same pathname, create a standard referral struct */
      struct referral* ref;
      self_referral = True;
      junction.referral_count = 1;
      if((ref = (struct referral*) malloc(sizeof(struct referral))) == NULL)
	{
	  DEBUG(0,("malloc failed for referral\n"));
	  return -1;
	}
      
      pstrcpy(ref->alternate_path,pathname);
      ref->proximity = 0;
      ref->ttl = REFERRAL_TTL;
      junction.referral_list = ref;
    }
  else
    {
      self_referral = False;
      if( DEBUGLVL( 3 ) )
	{
	  int i=0;
	  dbgtext("setup_dfs_referral: Referring client request for %s to alternate path(s):",pathname);
	  for(i=0;i<junction.referral_count;i++)
	    dbgtext(" %s",junction.referral_list[i].alternate_path);
	  dbgtext(".\n");
	}
    }
      
  /* create the referral depeding on version */
  DEBUG(10,("MAX_REFERRAL_LEVEL :%d\n",max_referral_level));
  if(max_referral_level<2 || max_referral_level>3) max_referral_level = 2;

  switch(max_referral_level)
    {
    case 2:
      {
	unsigned char uni_requestedpath[1024];
	unsigned char uni_altpath[1024];
	int uni_reqpathoffset1,uni_reqpathoffset2;
	int uni_curroffset;
	int requestedpathlen=0;
	int offset;
	int i=0;

	DEBUG(10,("setting up version2 referral\nRequested path:\n"));

	requestedpathlen = (dos_struni2(uni_requestedpath,pathname,512)+1)*2;

	dump_data(10,uni_requestedpath,requestedpathlen);

	DEBUG(10,("ref count = %u\n",junction.referral_count));

	uni_reqpathoffset1 = REFERRAL_HEADER_SIZE + 
	  VERSION2_REFERRAL_SIZE * junction.referral_count;

	uni_reqpathoffset2 = uni_reqpathoffset1 + requestedpathlen;

	uni_curroffset = uni_reqpathoffset2 + requestedpathlen;

	reply_size = REFERRAL_HEADER_SIZE + VERSION2_REFERRAL_SIZE*junction.referral_count +
	  2 * requestedpathlen;
	DEBUG(10,("reply_size: %u\n",reply_size));

	/* add up the unicode lengths of all the referral paths */
	for(i=0;i<junction.referral_count;i++)
	  {
	    DEBUG(10,("referral %u : %s\n",i,junction.referral_list[i].alternate_path));
	    reply_size += (strlen(junction.referral_list[i].alternate_path)+1)*2;
	  }

	DEBUG(10,("reply_size = %u\n",reply_size));
	/* add the unexplained 0x16 bytes */
	reply_size += 0x16;

	pdata = *ppdata = Realloc(pdata,reply_size);
	if(pdata == NULL)
	  {
	    DEBUG(0,("malloc failed for Realloc!\n"));
	    return -1;
	  }

	/* copy in the dfs requested paths.. required for offset calculations */
	memcpy(pdata+uni_reqpathoffset1,uni_requestedpath,requestedpathlen);
	memcpy(pdata+uni_reqpathoffset2,uni_requestedpath,requestedpathlen);


	/* create the header */
	SSVAL(pdata,0,requestedpathlen-2); /* path consumed */
	SSVAL(pdata,2,junction.referral_count); /* number of referral in this pkt */
	if(self_referral)
	  SIVAL(pdata,4,DFSREF_REFERRAL_SERVER | DFSREF_STORAGE_SERVER); 
	else
	  SIVAL(pdata,4,DFSREF_STORAGE_SERVER);

	offset = 8;
	/* add the referral elements */
	for(i=0;i<junction.referral_count;i++)
	  {
	    struct referral* ref = &(junction.referral_list[i]);
	    int unilen;

	    SSVAL(pdata,offset,2); /* version 2 */
	    SSVAL(pdata,offset+2,VERSION2_REFERRAL_SIZE);
	    if(self_referral)
	      SSVAL(pdata,offset+4,1);
	    else
	      SSVAL(pdata,offset+4,0);
	    SSVAL(pdata,offset+6,0); /* ref_flags :use path_consumed bytes? */
	    SIVAL(pdata,offset+8,ref->proximity);
	    SIVAL(pdata,offset+12,ref->ttl);
	    
	    SSVAL(pdata,offset+16,uni_reqpathoffset1-offset);
	    SSVAL(pdata,offset+18,uni_reqpathoffset2-offset);
	    /* copy referred path into current offset */
	    unilen = (dos_struni2(pdata+uni_curroffset,ref->alternate_path,512)
		      +1)*2;
	    SSVAL(pdata,offset+20,uni_curroffset-offset);
	    
	    uni_curroffset += unilen;
	    offset += VERSION2_REFERRAL_SIZE;
	  }
	/* add in the unexplained 22 (0x16) bytes at the end */
	memset(pdata+uni_curroffset,'\0',0x16);
	free(junction.referral_list);
	break;
      }

    case 3:
      {
	unsigned char uni_reqpath[1024];
	unsigned char uni_altpath[1024];
	int uni_reqpathoffset1, uni_reqpathoffset2;
	int uni_curroffset;

	int reqpathlen = 0;
	int offset,i=0;
	
	DEBUG(10,("setting up version3 referral\n"));

	reqpathlen = (dos_struni2(uni_reqpath,pathname,512)+1)*2;
	
	dump_data(10,uni_reqpath,reqpathlen);

	uni_reqpathoffset1 = REFERRAL_HEADER_SIZE + VERSION3_REFERRAL_SIZE *
	  junction.referral_count;
	uni_reqpathoffset2 = uni_reqpathoffset1 + reqpathlen;
	reply_size = uni_curroffset = uni_reqpathoffset2 + reqpathlen;

	for(i=0;i<junction.referral_count;i++)
	  {
	    DEBUG(10,("referral %u : %s\n",i,junction.referral_list[i].alternate_path));
	    reply_size += (strlen(junction.referral_list[i].alternate_path)+1)*2;
	  }

	pdata = *ppdata = Realloc(pdata,reply_size);
	if(pdata == NULL)
	  {
	    DEBUG(0,("version3 referral setup: malloc failed for Realloc!\n"));
	    return -1;
	  }
	
	/* create the header */
	SSVAL(pdata,0,reqpathlen-2); /* path consumed */
	SSVAL(pdata,2,junction.referral_count); /* number of referral in this pkt */
	if(self_referral)
	  SIVAL(pdata,4,DFSREF_REFERRAL_SERVER | DFSREF_STORAGE_SERVER); 
	else
	  SIVAL(pdata,4,DFSREF_STORAGE_SERVER);
	
	/* copy in the reqpaths */
	memcpy(pdata+uni_reqpathoffset1,uni_reqpath,reqpathlen);
	memcpy(pdata+uni_reqpathoffset2,uni_reqpath,reqpathlen);
	
	offset = 8;
	for(i=0;i<junction.referral_count;i++)
	  {
	    struct referral* ref = &(junction.referral_list[i]);
	    int unilen;

	    SSVAL(pdata,offset,3); /* version 3 */
	    SSVAL(pdata,offset+2,VERSION3_REFERRAL_SIZE);
	    if(self_referral)
	      SSVAL(pdata,offset+4,1);
	    else
	      SSVAL(pdata,offset+4,0);

	    SSVAL(pdata,offset+6,0); /* ref_flags :use path_consumed bytes? */
	    SIVAL(pdata,offset+8,ref->ttl);
	    
	    SSVAL(pdata,offset+12,uni_reqpathoffset1-offset);
	    SSVAL(pdata,offset+14,uni_reqpathoffset2-offset);
	    /* copy referred path into current offset */
	    unilen = (dos_struni2(pdata+uni_curroffset,ref->alternate_path,512)
		      +1)*2;
	    SSVAL(pdata,offset+16,uni_curroffset-offset);
	    /* copy 0x10 bytes of 00's in the ServiceSite GUID */
	    memset(pdata+offset+18,'\0',16);

	    uni_curroffset += unilen;
	    offset += VERSION3_REFERRAL_SIZE;
	  }
	free(junction.referral_list);
	break;
      }
    }
  DEBUG(10,("DFS Referral pdata:\n"));
  dump_data(10,pdata,reply_size);
  return reply_size;
}

int dfs_path_error(char* inbuf, char* outbuf)
{
  enum remote_arch_types ra_type = get_remote_arch();
  BOOL NT_arch = ((ra_type==RA_WINNT) || (ra_type == RA_WIN2K));
  if(NT_arch && (global_client_caps & (CAP_NT_SMBS | CAP_STATUS32)) )
    {
      SSVAL(outbuf,smb_flg2,SVAL(outbuf,smb_flg2) | FLAGS2_32_BIT_ERROR_CODES);
      return(ERROR(0,0xc0000000|NT_STATUS_PATH_NOT_COVERED));
    }
  return(ERROR(ERRSRV,ERRbadpath)); 
}

#else
/* Stub functions if MS_DFS not defined */
int setup_dfs_referral(char* pathname, int max_referral_level, 
		       char** ppdata)
{
  return -1;
}

#endif

/* Trivial fn that chops off upper bytes to convert unicode to dos */
int unistr_to_dos(char* dst,uint16* src)	       
{
  pstring s;
  int i=0;

  for(i=0;SVAL(src,i*2) && i<1024;i++)
    {
      s[i]= SVAL(src,i*2) & 0xff;
    }
  s[i]=0;

  safe_strcpy(dst,s,1024);
  DEBUG(10,("converted unistring to %s\n",s));
}