/***************************************************************************/
/*  Module:      $Id: readconfig.c,v 1.3 1999/05/07 04:15:26 maf Exp $
/*  Description: readconfiguration file.
/*  Author:      maf
/*  Notes:
/***************************************************************************/

/*
$Log:
*/

/*
# KarlBridge remote authentication configuration file.

# lines with the first non white space character a # are ignored
# \ can be used as a continuation character.
# \H can be used to represent the client host in the src IP or dst IP fields

# authorization record format:
# lrange, hrange, src IP, dst IP, dst IP mask, timeout, bridge IP,  \
#  bridge community, service name 
#
# example:
#
# Hagerty Hall Public Labs  (KarlBridge @ 128.146.109.252)
# 128.146.81.2,128.146.81.250, \H, 0.0.0.0, 0.0.0.0, 30, 128.146.109.252, \
#   public, Off Campus Access
#
# Osu Campus Only CD-ROM server (128.146.4.99) (KarlBridge @ 128.146.4.252)
# 128.146.0.0,128.146.255.255, 128.146.4.99, \H, 255.255.255.255, 30, \
#   128.146.4.252, public, Current Publications CD-ROM Database
#
*/

#include <stdio.h>
#include "kbauth.h"
#include <sys/types.h>
#include <ctype.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

ReadConfigFile(db, fname)
struct KbRemAuthDatabase *db;
char *fname;
{

  FILE *FP;
  char buf[MAXCONFIGLINE], tmpBuf[MAXCONFIGLINE];
  char *p, *bufPtr;
  int err, recNo, lineNo, eolFlag, contFlag, longLineFlag, x;

  err = 0;
  FP = NULL;
  recNo = 0;
  contFlag = 0;
  lineNo = 0;

  if (!(FP = fopen(fname, "r"))) {
    perror(fname);
    err = 1;
    goto ReadConfigFileout;
  }

  while (!feof(FP)) {

    if (contFlag) {
      if (!fgets(tmpBuf, MAXCONFIGLINE, FP))
        goto cont1; /* \ on prev line, this line was blank */
      bufPtr = tmpBuf;
    } else {
      if (!fgets(buf, MAXCONFIGLINE, FP))
        continue; /* implicit exit from loop */
      bufPtr = buf;
      ++lineNo;
    }


    /* make sure this line ended in eol */
    eolFlag = 0;
    for (p = bufPtr; *p; ++p)
      if ((*p == '\n') || (*p == '\r')) {
        *p = 0;
        eolFlag = 1;
        break;
      }

    /* ignore all leading white space, note this is after the eol check
      so it will work */
    for (; isspace((int)*bufPtr); ++bufPtr);

    /* short circuit for blank lines */
    if (eolFlag && (!contFlag) && (!bufPtr[0]))
      continue;
      

    /* if this is a continuation line, add it on the end */
    if (contFlag) {
      if ((strlen(buf) + strlen(bufPtr) + 1) > MAXCONFIGLINE) 
        longLineFlag = 1;
      else {
        strcat(buf, tmpBuf);
        longLineFlag = 0;
      }
    }

    /* check for lines too long */
    if ((!eolFlag && !feof(FP)) || (contFlag && longLineFlag)) {
      fprintf(stderr, "%s, line %d too long\n", fname, lineNo);
      err = 1;
      goto ReadConfigFileout;
    }

    /* ignore comment lines (note, must be after too long check) */
    if (buf[0] == '#')
      continue;

cont1:
    /* lines that end with a \ need to be joined with the next line */
    x = strlen(buf);
    if (!x)
      x = 1;
    --x;
    if (buf[x] == '\\') {
      contFlag = 1;
      buf[x] = 0;
      continue;
    } else
      contFlag = 0;

    /* final check for blank line */
    if (!buf[0])
      continue;

    /* Parse the line */
    p = buf;

    /* make sure there are records left to be filled */
    if (recNo >= MAXAUTHRECORDS) {
      fprintf(stderr, "Maximum authentication records (%d) exceeded.\n", 
        (int)MAXAUTHRECORDS);
      err = 1;
      goto ReadConfigFileout;
    }

    /* lrange */
    if (GetField(&p, tmpBuf, "lrange", lineNo)) {
      err = 1;
      goto ReadConfigFileout;
    }

    db[recNo].ipLow = htonl((u_long)inet_addr(tmpBuf));
    
    /* hrange */
    if (GetField(&p, tmpBuf, "hrange", lineNo)) {
      err = 1;
      goto ReadConfigFileout;
    }

    db[recNo].ipHigh = htonl((u_long)inet_addr(tmpBuf));

    /* srcIP */
    if (GetField(&p, tmpBuf, "srcIP", lineNo)) {
      err = 1;
      goto ReadConfigFileout;
    }

    if (!strcmp(tmpBuf, "\\H"))
      db[recNo].srcIP = 0xFFFFFFFF;
    else 
      db[recNo].srcIP = htonl((u_long)inet_addr(tmpBuf));

    /* dstIP */
    if (GetField(&p, tmpBuf, "dstIP", lineNo)) {
      err = 1;
      goto ReadConfigFileout;
    }

    if (!strcmp(tmpBuf, "\\H"))
      db[recNo].dstIP = 0xFFFFFFFF;
    else
      db[recNo].dstIP = htonl((u_long)inet_addr(tmpBuf));
    
    /* dstIPMask */
    if (GetField(&p, tmpBuf, "dstIPMask", lineNo)) {
      err = 1;
      goto ReadConfigFileout;
    }

    db[recNo].dstIPMask = htonl((u_long)inet_addr(tmpBuf));

    /* timeout */
    if (GetField(&p, tmpBuf, "timeout", lineNo)) {
      err = 1;
      goto ReadConfigFileout;
    }

    db[recNo].timeOut = (u_long)atol(tmpBuf);

    /* bridgeIP */
    if (GetField(&p, tmpBuf, "bridgeIP", lineNo)) {
      err = 1;
      goto ReadConfigFileout;
    }

    db[recNo].bridgeIP = htonl((u_long)inet_addr(tmpBuf));

    /* bridgeCommunity */
    if (GetField(&p, tmpBuf, "bridgeCommunity", lineNo)) {
      err = 1;
      goto ReadConfigFileout;
    }

    if (strlen(tmpBuf) > MAXCOMMUNITYNAME) {
      fprintf(stderr, "Community name (line %d) is too long\n", lineNo);
      err = 1;
      goto ReadConfigFileout;
    }
    strcpy(db[recNo].bridgeCommunity, tmpBuf);


    /* serviceName is rest of line */
    for (; isspace((int)*p); ++p);
    if (strlen(p) > MAXSERVICENAME) {
      fprintf(stderr, "Field serviceName (line %d) is too long\n",
        lineNo);
      err = 1;
      goto ReadConfigFileout;
    }
    strcpy(db[recNo].serviceName, p);

    ++recNo;

  } /* while !feof() */

  err = 0; /* good */

ReadConfigFileout:

  if (FP)
    fclose(FP);

  if (err)
    return err;
  else {
    db[recNo].ipLow = 0xFFFFFFFF; /* mark end */
    return 0; /* good */
  }
}

int GetField(c, buf, msg, lineNo)
char **c, *buf, *msg;
int lineNo;
{
  char *p;
  int x;

  
  p = (char*)*c; /* easy deref */
  buf[0] = 0;

  /* skip whitespace */
  for (; isspace((int)*p); ++p);

  for (x = 0; *p && (*p != ','); ++x, ++p)
    buf[x] = *p;

  if (!buf[0]) {
    fprintf(stderr, "Field %s (line %d) is missing\n", msg, lineNo);
    return 1;
  }

  buf[x] = 0;
  *c = ++p;

  return 0;

} /* GetField */