/* mod_ntlm file: $Id: rfcnb-util.inc.c,v 1.2 2003/02/21 01:55:14 casz Exp $ */

/* UNIX RFCNB (RFC1001/RFC1002) NetBIOS implementation
 *
 * Version 1.0 RFCNB Utility Routines ...
 *
 * Copyright (C) Richard Sharpe 1996
 *
 */

/*
 * 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 <string.h>
#include <stdlib.h>
#include <stdint.h>

#include "std-includes.h"
#include "rfcnb-priv.h"
#include "rfcnb-util.h"
#include "rfcnb-io.h"

/* Convert name and pad to 16 chars as needed.  Name 1 is a C string
 * with null termination, name 2 may not be.  If SysName is true, then
 * put a <00> on end, else space> */
static void
RFCNB_CvtPad_Name(char *name1, char *name2)
{
    char c, c1, c2;
    int i, len;

    len = strlen(name1);
    for (i = 0; i < 16; i++) {
        if (i >= len) {
            c1 = 'C';
            c2 = 'A';           /* CA is a space */
        } else {
            c = name1[i];
            c1 = (char) ((int) c / 16 + (int) 'A');
            c2 = (char) ((int) c % 16 + (int) 'A');
        }
        name2[i * 2] = c1;
        name2[i * 2 + 1] = c2;
    }
    name2[32] = 0;              /* Put in the nll ... */
}

/* Get a packet of size n */
static struct RFCNB_Pkt *
RFCNB_Alloc_Pkt(int n)
{
    RFCNB_Pkt *pkt;

    if ((pkt = (struct RFCNB_Pkt *) malloc(
                            sizeof(struct RFCNB_Pkt))) == NULL) {
        RFCNB_errno = RFCNBE_NoSpace;
        RFCNB_saved_errno = errno;
        return NULL;
    }
    pkt->next = NULL;
    pkt->len = n;

    if (n == 0)
        return pkt;

    if ((pkt->data = (char *) malloc(n)) == NULL) {
        RFCNB_errno = RFCNBE_NoSpace;
        RFCNB_saved_errno = errno;
        free(pkt);
        return (NULL);
    }
    return pkt;
}

/* Free up a packet */
static void
RFCNB_Free_Pkt(struct RFCNB_Pkt *pkt)
{
    struct RFCNB_Pkt *pkt_next;
    char *data_ptr;

    while (pkt != NULL) {
        pkt_next = pkt->next;
        data_ptr = pkt->data;
        if (data_ptr != NULL)
            free(data_ptr);
        free(pkt);
        pkt = pkt_next;
    }
}

/* Resolve a name into an address */
static int
RFCNB_Name_To_IP(char *host, struct in_addr *Dest_IP)
{
    int addr;                   /* Assumes IP4, 32 bit network addresses */
    struct hostent *hp;

    /* Use inet_addr to try to convert the address */
    if ((addr = inet_addr(host)) == INADDR_NONE) { /* a good try :-) */
        /* Now try a name look up with gethostbyname */
        if ((hp = gethostbyname(host)) == NULL) { /* Not in DNS */
            /* Try NetBIOS name lookup, how the hell do we do that? */
            RFCNB_errno = RFCNBE_BadName;         /* Is this right? */
            RFCNB_saved_errno = errno;
            return (RFCNBE_Bad);
        } else {                /* We got a name */
            memcpy((void *) Dest_IP, (void *) hp->h_addr_list[0],
                   sizeof(struct in_addr));
        }
    } else {                    /* It was an IP address */
        memcpy((void *) Dest_IP, (void *) &addr, sizeof(struct in_addr));
    }
    return 0;
}

/* Disconnect the TCP connection to the server */
static int
RFCNB_Close(int socket)
{
    close(socket);
    /* If we want to do error recovery, here is where we put it */
    return 0;
}

/* Connect to the server specified in the IP address. Not sure how to
 * handle socket options etc.  */
static int
RFCNB_IP_Connect(struct in_addr Dest_IP, int port)
{
    struct sockaddr_in Socket;
    int fd;

    /* Create a socket */
    if ((fd = socket(PF_INET, SOCK_STREAM, 0)) < 0) { /* Handle the error */
        RFCNB_errno = RFCNBE_BadSocket;
        RFCNB_saved_errno = errno;
        return (RFCNBE_Bad);
    }
    bzero((char *) &Socket, sizeof(Socket));
    memcpy((char *) &Socket.sin_addr, (char *) &Dest_IP, sizeof(Dest_IP));

    Socket.sin_port = htons(port);
    Socket.sin_family = PF_INET;

    /* Now connect to the destination */
    if (connect(fd, (struct sockaddr *) &Socket, sizeof(Socket)) < 0) {
        /* Error */
        close(fd);
        RFCNB_errno = RFCNBE_ConnectFailed;
        RFCNB_saved_errno = errno;
        return (RFCNBE_Bad);
    }
    return fd;
}

/* handle the details of establishing the RFCNB session with remote end */
static int
RFCNB_Session_Req(struct RFCNB_Con *con,
                  char *Called_Name,
                  char *Calling_Name,
                  BOOL * redirect,
                  struct in_addr *Dest_IP,
                  int *port)
{
    char *sess_pkt;

    /* Response packet should be no more than 9 bytes, make 16 jic */
    char resp[16];
    int len;
    struct RFCNB_Pkt *pkt, res_pkt;

    /* We build and send the session request, then read the response */
    pkt = RFCNB_Alloc_Pkt(RFCNB_Pkt_Sess_Len);
    if (pkt == NULL) {
        return RFCNBE_Bad; /* Leave the error that RFCNB_Alloc_Pkt gives) */
    }
    sess_pkt = pkt->data;       /* Get pointer to packet proper */

    sess_pkt[RFCNB_Pkt_Type_Offset] = RFCNB_SESSION_REQUEST;
    RFCNB_Put_Pkt_Len(sess_pkt, RFCNB_Pkt_Sess_Len - RFCNB_Pkt_Hdr_Len);
    sess_pkt[RFCNB_Pkt_N1Len_Offset] = 32;
    sess_pkt[RFCNB_Pkt_N2Len_Offset] = 32;

    RFCNB_CvtPad_Name(Called_Name, (sess_pkt + RFCNB_Pkt_Called_Offset));
    RFCNB_CvtPad_Name(Calling_Name, (sess_pkt + RFCNB_Pkt_Calling_Offset));

    /* Now send the packet */
#ifdef RFCNB_DEBUG
    fprintf(stderr, "Sending packet: ");
#endif
    if ((len = RFCNB_Put_Pkt(con, pkt, RFCNB_Pkt_Sess_Len)) < 0)
        return RFCNBE_Bad;      /* Should be able to write that lot ... */
#ifdef RFCNB_DEBUG
    fprintf(stderr, "Getting packet.\n");
#endif

    res_pkt.data = resp;
    res_pkt.len = sizeof(resp);
    res_pkt.next = NULL;

    if ((len = RFCNB_Get_Pkt(con, &res_pkt, sizeof(resp))) < 0)
        return RFCNBE_Bad;

    /* Now analyze the packet ... */
    switch (RFCNB_Pkt_Type(resp)) {
      case RFCNB_SESSION_REJ:   /* Didnt like us ... too bad */
          /* Why did we get rejected ? */
          switch (CVAL(resp, RFCNB_Pkt_Error_Offset)) {
            case 0x80:
                RFCNB_errno = RFCNBE_CallRejNLOCN;
                break;
            case 0x81:
                RFCNB_errno = RFCNBE_CallRejNLFCN;
                break;
            case 0x82:
                RFCNB_errno = RFCNBE_CallRejCNNP;
                break;
            case 0x83:
                RFCNB_errno = RFCNBE_CallRejInfRes;
                break;
            case 0x8F:
                RFCNB_errno = RFCNBE_CallRejUnSpec;
                break;
            default:
                RFCNB_errno = RFCNBE_ProtErr;
                break;
          }
          return (RFCNBE_Bad);
          break;

      case RFCNB_SESSION_ACK:   /* Got what we wanted ...      */
          return (0);
          break;

      case RFCNB_SESSION_RETARGET:      /* Go elsewhere                */
          *redirect = TRUE;     /* Copy port and ip addr       */
          memcpy(Dest_IP, (resp + RFCNB_Pkt_IP_Offset),
                 sizeof(struct in_addr));
          *port = SVAL(resp, RFCNB_Pkt_Port_Offset);
          return 0;
          break;
      default:                  /* A protocol error */
          RFCNB_errno = RFCNBE_ProtErr;
          return (RFCNBE_Bad);
          break;
    }
}