- Thu Feb 8 20:12:39 UTC 2001

[libfaim.git] / aim_ft.c

/*
 * File transfer (OFT) and DirectIM.
 */

#define FAIM_INTERNAL_FT
#define FAIM_INTERNAL
#include <faim/aim.h>

#ifndef _WIN32
#include <netdb.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <sys/utsname.h> /* for aim_directim_initiate */

#include <arpa/inet.h> /* for inet_ntoa */

#endif

/* TODO: 
   o fix misspelling of receive 
   o double-check mutex states on error returns 
   o look for memory leaks.. there's going to be shitloads, i'm sure. 
   o change listing FILE to listing filesend callback 
   o change send_file and send_chunk over to buffers.
*/

static struct aim_fileheader_t *aim_oft_getfh(unsigned char *hdr);
 
/**
 * aim_handlerendconnect - call this to accept OFT connections and set up the requisite structures
 * @sess: the session
 * @cur: the conn the incoming connection is on
 *
 * call this when you get an outstanding read on a conn with subtype
 * AIM_CONN_SUBTYPE_RENDEZVOUS_OUT, it will close the current fd and
 * call a callback with the new, accept'd fd to the other person. then we
 * get to start the fun that is OFT!
 */
faim_export int aim_handlerendconnect(struct aim_session_t *sess, struct aim_conn_t *cur)
{ 
  int acceptfd = 0;
  rxcallback_t userfunc;
  struct sockaddr cliaddr;
  socklen_t clilen = sizeof(cliaddr);
  int ret = 0;
  struct aim_conn_t *newconn;

  if( (acceptfd = accept(cur->fd, &cliaddr, &clilen)) == -1)
    return -1;
  if (cliaddr.sa_family != AF_INET) { /* just in case IPv6 really is happening */
    close(acceptfd);
    aim_conn_close(cur);
    return -1;
  } 

  /* clone it and then close the original */
  /* XXX safe? maybe cur->priv should be NULLed after this */
  if (!(newconn = aim_cloneconn(sess, cur))) {
    close(acceptfd);
    aim_conn_close(cur);
    return -1;
  }
  aim_conn_close(cur);

  newconn->type = AIM_CONN_TYPE_RENDEZVOUS;
  newconn->fd = acceptfd;

  switch(newconn->subtype) { 
  case AIM_CONN_SUBTYPE_OFT_DIRECTIM: { 
    struct aim_directim_priv *priv;

    if(!newconn->priv)
      newconn->priv = (struct aim_directim_priv *)calloc(1, sizeof(struct aim_directim_priv));
    priv = (struct aim_directim_priv *)newconn->priv;

    snprintf(priv->ip, sizeof(priv->ip), "%s:%u", 
	     inet_ntoa(((struct sockaddr_in *)&cliaddr)->sin_addr), 
	     ntohs(((struct sockaddr_in *)&cliaddr)->sin_port));

    /* should we really do this? seems like the client should decide. maybe clone the connection and keep the listener open. -- mid */
    if ( (userfunc = aim_callhandler(newconn, AIM_CB_FAM_OFT, AIM_CB_OFT_DIRECTIMINITIATE)))
      ret = userfunc(sess, NULL, newconn);

    break;
  } 
  case AIM_CONN_SUBTYPE_OFT_GETFILE: { 
    struct aim_filetransfer_priv *priv;

    if(!newconn->priv)
      newconn->priv = (struct aim_filetransfer_priv *)calloc(1, sizeof(struct aim_filetransfer_priv));
    priv = (struct aim_filetransfer_priv *)newconn->priv;

    snprintf(priv->ip, sizeof(priv->ip), "%s:%u", inet_ntoa(((struct sockaddr_in *)&cliaddr)->sin_addr), ntohs(((struct sockaddr_in *)&cliaddr)->sin_port));

    if ( (userfunc = aim_callhandler(newconn, AIM_CB_FAM_OFT, AIM_CB_OFT_GETFILEINITIATE)))
      ret = userfunc(sess, NULL, newconn);

    break;
  } 
  default: { 
    faimdprintf(1,"Got a Connection on a listener that's not Rendezvous(??!) Killing conn.\n");
    aim_conn_close(newconn);
    break;
  }
  }

  return ret;
}
 
/*
 * aim_send_im_direct - send IM client-to-client over established connection
 * @sess: session to conn
 * @conn: directim connection
 * @msg: null-terminated string to send; if this is NULL, it will send a "typing" notice. 
 *
 */
faim_export int aim_send_im_direct(struct aim_session_t *sess, struct aim_conn_t *conn, char *msg)
{ 

  struct command_tx_struct *newpacket;
  struct aim_directim_priv *priv = NULL;
  int i;
  if (!sess || !conn || (conn->type != AIM_CONN_TYPE_RENDEZVOUS) || !conn->priv) { 
    faimdprintf(2,"faim: directim: invalid arguments\n");
    return -1;
  }

  priv = (struct aim_directim_priv *)conn->priv;

  if (!(newpacket = aim_tx_new(AIM_FRAMETYPE_OFT, 0x0001, conn, strlen(msg)))) { 
    faimdprintf(2,"faim: directim: tx_new failed\n");
    return -1;
  } 

  newpacket->lock = 1;

  /* if msg is non-null, we'resending an IM, else a "typing" notice */
  if(msg) { 
    if (strlen(msg) >= MAXMSGLEN)
      return -1;
    newpacket->hdr.oft.hdr2len = 0x54;
    if (!(newpacket->hdr.oft.hdr2 = calloc(1,newpacket->hdr.oft.hdr2len))) { 
      newpacket->lock = 0;
      aim_tx_destroy(newpacket);
      return -1;
    } 
  } else { 
    newpacket->hdr.oft.hdr2len = 0x44;
    if (!(newpacket->hdr.oft.hdr2 = calloc(1,newpacket->hdr.oft.hdr2len))) { 
      newpacket->lock = 0;
      aim_tx_destroy(newpacket);
      return -1;
    } 
  } 

  memcpy(newpacket->hdr.oft.magic, "ODC2", 4);
  newpacket->data = NULL;

  i = 0;
  i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0006);
  i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);
  i += aimutil_putstr(newpacket->hdr.oft.hdr2+i, (char *)priv->cookie, 8);
  i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);
  i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);
  i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);
  i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);
  i += aimutil_put32(newpacket->hdr.oft.hdr2+i, 0x00000000);
  i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);
  i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);
  i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);

  /* flags -- 0x000e for "typing", 0x0000 for message */
  if(msg)
    i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);
  else 
    i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x000e);

  i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);
  i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);
  i += aimutil_putstr(newpacket->hdr.oft.hdr2+i, sess->sn, strlen(sess->sn));
  i = 52;

  i += aimutil_put8(newpacket->hdr.oft.hdr2+i, 0x00);
  i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);
  i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);
  i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);
  i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);
  i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);
  i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);
  i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);

  /* end of hdr2 */

  if(msg) { 
    /* values grabbed from a dump */
    i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0008);
    i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x000c);
    i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0000);
    i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x1466);
    i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x0001);
    i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x2e0f);
    i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0x393e);
    i += aimutil_put16(newpacket->hdr.oft.hdr2+i, 0xcac8);
    memcpy(newpacket->data, msg, strlen(msg));
  } 
  newpacket->lock = 0;
  aim_tx_enqueue(sess, newpacket);
  return 0;
} 

/*
 * aim_directim_intitiate - For those times when we want to open up the directim channel ourselves.
 * @sess: your session,
 * @conn: the BOS conn,
 * @priv: a dummy priv value (we'll let it get filled in later) (if you pass a NULL, we alloc one)
 * @destsn: the SN to connect to.
 *
 */
faim_export struct aim_conn_t *aim_directim_initiate(struct aim_session_t *sess, 
						     struct aim_conn_t *conn, 
						     struct aim_directim_priv *priv, 
						     char *destsn)
{ 

  struct command_tx_struct *newpacket;
  struct aim_conn_t *newconn;
  struct aim_msgcookie_t *cookie;
  int curbyte, i, listenfd;
  short port = 4443;
  struct hostent *hptr;
  char localhost[129];
  unsigned char cap[16];
  char d[4]; /* IPv6 is a bit bigger... */

  /* XXX: TLVlist-ize this */
 
  /* Open our socket */

  if( (listenfd = aim_listenestablish(port)) == -1)
    return NULL;

  /* get our local IP */
  /* XXX if available, use getaddrinfo() */
  /* XXX allow client to specify which IP to use for multihomed boxes */
  if(gethostname(localhost, 128) < 0)
    return NULL;
  if( (hptr = gethostbyname(localhost)) == NULL)
    return NULL;
  memcpy(&d, hptr->h_addr_list[0], 4);

  /* XXX: this probably isn't quite kosher, but it works */
  aim_putcap(cap, 16, AIM_CAPS_IMIMAGE);

  /* create the OSCAR packet */

  if (!(newpacket = aim_tx_new(AIM_FRAMETYPE_OSCAR, 0x0002, conn, 10+8+2+1+strlen(destsn)+4+4+0x32)))
    return NULL;
  newpacket->lock = 1;

  curbyte = 0;
  curbyte += aim_putsnac(newpacket->data+curbyte, 0x0004, 0x0006, 0x0000, sess->snac_nextid);

  /* Generate a random message cookie */
  /* This cookie needs to be alphanumeric and NULL-terminated to be TOC-compatible. */
  for (i=0; i<7; i++) 
    curbyte += aimutil_put8(newpacket->data+curbyte, 0x30 + ((u_char) rand() % 20));

  curbyte += aimutil_put8(newpacket->data+curbyte, 0x00);

  /* grab all the data for cookie caching */
  cookie = (struct aim_msgcookie_t *)calloc(1, sizeof(struct aim_msgcookie_t));
  memcpy(cookie->cookie, newpacket->data+curbyte-8, 8);
  cookie->type = AIM_COOKIETYPE_OFTIM;
  priv = cookie->data;

  if(!priv)
    priv = (struct aim_directim_priv *)calloc(1, sizeof(struct aim_directim_priv));
 
  memcpy(priv->cookie, cookie, 8);
  memcpy(priv->sn, destsn, sizeof(priv->sn));
  cookie->data = priv;
  aim_cachecookie(sess, cookie);

  /* Channel ID */
  curbyte += aimutil_put16(newpacket->data+curbyte,0x0002);

  /* Destination SN (prepended with byte length)*/
  curbyte += aimutil_put8(newpacket->data+curbyte,strlen(destsn));
  curbyte += aimutil_putstr(newpacket->data+curbyte, destsn, strlen(destsn));
  curbyte += aimutil_put16(newpacket->data+curbyte, 0x0003);
  curbyte += aimutil_put16(newpacket->data+curbyte, 0x0000);

  /* enTLV start */
  curbyte += aimutil_put16(newpacket->data+curbyte, 0x0005);
  curbyte += aimutil_put16(newpacket->data+curbyte, 0x0032);

  /* Flag data / ICBM Parameters  */
  curbyte += aimutil_put8(newpacket->data+curbyte, 0x00);
  curbyte += aimutil_put8(newpacket->data+curbyte, 0x00);

  /* Cookie  */
  curbyte += aimutil_putstr(newpacket->data+curbyte, (char *)cookie, 8);

  /*Capability String  */
  curbyte += aimutil_putstr(newpacket->data+curbyte, (char *)cap, 0x10);

  /* 000a/0002 : 0001  */
  curbyte += aimutil_put16(newpacket->data+curbyte, 0x000a);
  curbyte += aimutil_put16(newpacket->data+curbyte, 0x0002);
  curbyte += aimutil_put16(newpacket->data+curbyte, 0x0001);

  /* 0003/0004: IP address  */
  curbyte += aimutil_put16(newpacket->data+curbyte, 0x0003);
  curbyte += aimutil_put16(newpacket->data+curbyte, 0x0004);
  for(i = 0;i < 4; i++) 
    curbyte += aimutil_put8(newpacket->data+curbyte, d[i]);
 
  /* 0005/0002: Port */
  curbyte += aimutil_put16(newpacket->data+curbyte, 0x0005);
  curbyte += aimutil_put16(newpacket->data+curbyte, 0x0002);
  curbyte += aimutil_put16(newpacket->data+curbyte, port);

  /* 000f/0000: ?? */
  curbyte += aimutil_put16(newpacket->data+curbyte, 0x000f);
  curbyte += aimutil_put16(newpacket->data+curbyte, 0x0000);
  newpacket->commandlen = curbyte;
  newpacket->lock = 0;
  aim_tx_enqueue(sess, newpacket);


  /* XXX switch to aim_cloneconn()? */
  if (!(newconn = aim_newconn(sess, AIM_CONN_TYPE_RENDEZVOUS_OUT, NULL)))
    return NULL;

  newconn->fd = listenfd;
  newconn->subtype = AIM_CONN_SUBTYPE_OFT_DIRECTIM;
  newconn->priv = priv;
  newconn->lastactivity = time(NULL);

  faimdprintf(2,"faim: listening (fd = %d, unconnected)\n", newconn->fd);

  return newconn;
} 

/*
 * unsigned long aim_oft_listener_clean - close up old listeners
 * @sess: session to clean up in
 * @age: maximum age in seconds 
 *
 * returns number closed, -1 on error.
 */
faim_export unsigned int aim_oft_listener_clean(struct aim_session_t *sess, time_t age) 
{ 
  struct aim_conn_t *cur;
  time_t now;
  unsigned int hit = 0;
  
  if(!sess)
    return -1;
  now = time(NULL);
  faim_mutex_lock(&sess->connlistlock);
  for(cur = sess->connlist;cur; cur = cur->next)
    if(cur->type == AIM_CONN_TYPE_RENDEZVOUS_OUT) { 
      faim_mutex_lock(&cur->active);
      if (cur->lastactivity < (now - age) ) { 
	faim_mutex_unlock(&cur->active);
	aim_conn_close(cur);
	hit++;
      } else 
	faim_mutex_unlock(&cur->active);
    } 
  faim_mutex_unlock(&sess->connlistlock);
  return hit;
} 

/*
 * aim_directim_connect - connect to buddy for directim
 * @sess: the session to append the conn to,
 * @conn: the BOS connection,
 * @priv: the filled-in priv data structure for the connection 
 *
 * returns conn if connected, %NULL on error
 */
faim_export struct aim_conn_t *aim_directim_connect(struct aim_session_t *sess, struct aim_conn_t *conn, struct aim_directim_priv *priv)
{ 
  struct aim_conn_t *newconn = NULL;

  if(!sess || !conn || !priv)
    return NULL;
  
  /* XXX verify that non-blocking connects actually work */
  newconn = aim_newconn(sess, AIM_CONN_TYPE_RENDEZVOUS, priv->ip);
  if (!newconn || (newconn->fd == -1)) { 
    faimdprintf(2, "could not connect to %s\n", priv->ip);
    perror("aim_newconn");
    /* Its safe to call conn_kill here since we created the connection */
    if (newconn)
      aim_conn_kill(sess, &newconn);
    return NULL;
  }

  newconn->subtype = AIM_CONN_SUBTYPE_OFT_DIRECTIM;
  newconn->priv = priv;
  faimdprintf(2, "faim: connected to peer (fd = %d)\n", newconn->fd);

  return newconn;
} 

/*
 * aim_directim_getconn - find a directim conn for buddy name
 * @sess: your session,
 * @name: the name to get,  
 *
 * returns conn for directim with name, %NULL if none found. 
 *
 */
faim_export struct aim_conn_t *aim_directim_getconn(struct aim_session_t *sess, const char *name)
{
  struct aim_conn_t *cur;
  struct aim_directim_priv *priv;

  if(!sess || !name)
    return NULL;

  faim_mutex_lock(&sess->connlistlock);

  for (cur = sess->connlist; cur; cur = cur->next) {
    if (cur->type != AIM_CONN_TYPE_RENDEZVOUS || cur->subtype != AIM_CONN_SUBTYPE_OFT_DIRECTIM)
      continue;
    priv = cur->priv;
    if (aim_sncmp(priv->sn, name) == 0)
      break;
  } faim_mutex_unlock(&sess->connlistlock);
  return cur;
} 

/*
 * aim_accepttransfer - accept a file transfer request
 * @sess: the session,
 * @conn: the BOS conn for the CAP reply
 * @sn: the screenname to send it to,
 * @cookie: the cookie used
 * @ip: the ip to connect to
 * @listingfiles: number of files to share
 * @listingtotsize: total size of shared files
 * @listingsize: length of the listing file(buffer)
 * @listingchecksum: checksum of the listing
 * @rendid: capability type (%AIM_CAPS_GETFILE or %AIM_CAPS_SENDFILE)  
 *
 * returns connection or %NULL on error.
 */
faim_export struct aim_conn_t *aim_accepttransfer(struct aim_session_t *sess, 
						  struct aim_conn_t *conn, 
						  char *sn, char *cookie, 
						  char *ip, 
						  unsigned short listingfiles, 
						  unsigned short listingtotsize, 
						  unsigned short listingsize, 
						  unsigned int listingchecksum, 
						  unsigned short rendid)
{ 
  struct command_tx_struct *newpacket, *newoft;
  struct aim_conn_t *newconn;
  struct aim_fileheader_t *fh;
  struct aim_filetransfer_priv *priv;
  struct aim_msgcookie_t *cachedcook;
  int curbyte, i;

  if(!sess || !conn || !sn || !cookie || !ip)
    return NULL;

  if(rendid == AIM_CAPS_GETFILE)  {
    newconn = aim_newconn(sess, AIM_CONN_TYPE_RENDEZVOUS, ip);
    newconn->subtype = AIM_CONN_SUBTYPE_OFT_GETFILE;

    if (!newconn || (newconn->fd == -1)) {
      perror("aim_newconn");
      faimdprintf(2, "could not connect to %s (fd: %i)\n", ip, newconn?newconn->fd:0);
      /* Its safe to call conn_kill here since we created the connection */
      if (newconn)
	aim_conn_kill(sess, &newconn);
      return NULL;
    } else {
      priv = (struct aim_filetransfer_priv *)calloc(1, sizeof(struct aim_filetransfer_priv));

      memcpy(priv->cookie, cookie, 8);
      priv->state = 0;
      strncpy(priv->sn, sn, MAXSNLEN);
      strncpy(priv->ip, ip, sizeof(priv->ip));
      newconn->priv = (void *)priv;

      faimdprintf(2, "faim: connected to peer (fd = %d)\n", newconn->fd);
    }

    if(rendid == AIM_CAPS_GETFILE) { 
      faimdprintf(2, "faim: getfile request accept\n");

      if(!(newoft = aim_tx_new(AIM_FRAMETYPE_OFT, 0x1108, newconn, 0))) { 
	faimdprintf(2, "faim: aim_accepttransfer: tx_new OFT failed\n");
	/* Its safe to call conn_kill here since we created the connection */
	aim_conn_kill(sess, &newconn);
	return NULL;
      } 

      newoft->lock = 1;
      memcpy(newoft->hdr.oft.magic, "OFT2", 4);
      newoft->hdr.oft.hdr2len = 0x100 - 8;

      if(!(fh = (struct aim_fileheader_t*)calloc(1, sizeof(struct aim_fileheader_t))))
	return NULL;

      fh->encrypt = 0x0000;
      fh->compress = 0x0000;
      fh->totfiles = listingfiles;
      fh->filesleft = listingfiles;      /* is this right -- total parts and parts left?*/
      fh->totparts = 0x0001;
      fh->partsleft = 0x0001;
      fh->totsize = listingtotsize;
      fh->size = listingsize;      /* ls -l listing.txt */
      fh->modtime = (int)time(NULL); /* we'll go with current time for now */
      fh->checksum = listingchecksum;
      fh->rfcsum = 0x00000000;
      fh->rfsize = 0x00000000;
      fh->cretime = 0x00000000;
      fh->rfcsum = 0x00000000;
      fh->nrecvd = 0x00000000;
      fh->recvcsum = 0x00000000;
      memset(fh->idstring, 0, sizeof(fh->idstring));
      memcpy(fh->idstring, "OFT_Windows ICBMFT V1.1 32", sizeof(fh->idstring));
      fh->flags = 0x02;
      fh->lnameoffset = 0x1a;
      fh->lsizeoffset = 0x10;
      memset(fh->dummy, 0, sizeof(fh->dummy));
      memset(fh->macfileinfo, 0, sizeof(fh->macfileinfo));

      /* we need to figure out these encodings for filenames */
      fh->nencode = 0x0000;
      fh->nlanguage = 0x0000;
      memset(fh->name, 0, sizeof(fh->name));
      memcpy(fh->name, "listing.txt", sizeof(fh->name));

      if (!(newoft->hdr.oft.hdr2 = (char *)calloc(1,newoft->hdr.oft.hdr2len))) { 
	newoft->lock = 0;
	aim_tx_destroy(newoft);
	return NULL;
      } 

      memcpy(fh->bcookie, cookie, 8);

      if(!(aim_oft_buildheader((unsigned char *)newoft->hdr.oft.hdr2, fh)))
	printf("eek, bh fail!\n");

      newoft->lock = 0;
      aim_tx_enqueue(sess, newoft);
   
      if(!(cachedcook = (struct aim_msgcookie_t *)calloc(1, sizeof(struct aim_msgcookie_t)))) { 
	faimdprintf(1, "faim: accepttransfer: couldn't calloc cachedcook. yeep!\n");
	/* more cleanup */
	return NULL;
      }

      memcpy(&(priv->fh), fh, sizeof(struct aim_fileheader_t));
      memcpy(cachedcook->cookie, cookie, 8);

      cachedcook->type = AIM_COOKIETYPE_OFTGET;
      cachedcook->data = (void *)priv;

      if (aim_cachecookie(sess, cachedcook) != 0)
	faimdprintf(1, "faim: ERROR caching message cookie\n");

      free(fh);
    } 
 
    /* OSCAR CAP accept packet */
    
    if(!(newpacket = aim_tx_new(AIM_FRAMETYPE_OSCAR, 0x0002, conn, 10+8+2+1+strlen(sn)+4+2+8+16)))
      return NULL;

    newpacket->lock = 1;
    curbyte = aim_putsnac(newpacket->data, 0x0004, 0x0006, 0x0000, sess->snac_nextid);

    for (i = 0;	 i < 8;	 i++)
      curbyte += aimutil_put8(newpacket->data+curbyte, cookie[i]);

    curbyte += aimutil_put16(newpacket->data+curbyte, 0x0002);
    curbyte += aimutil_put8(newpacket->data+curbyte, strlen(sn));
    curbyte += aimutil_putstr(newpacket->data+curbyte, sn, strlen(sn));
    curbyte += aimutil_put16(newpacket->data+curbyte, 0x0005);
    curbyte += aimutil_put16(newpacket->data+curbyte, 0x001a);
    curbyte += aimutil_put16(newpacket->data+curbyte, 0x0002 /* accept*/);

    for (i = 0;i < 8; i++) 
      curbyte += aimutil_put8(newpacket->data+curbyte, cookie[i]);

    curbyte += aim_putcap(newpacket->data+curbyte, 0x10, rendid);
    newpacket->lock = 0;
    aim_tx_enqueue(sess, newpacket);

    return newconn;
  } return NULL;
}

/*
 * aim_getlisting(FILE *file) -- get an aim_fileheader_t for a given FILE*
 *  @file is an opened listing file
 * 
 * returns a pointer to the filled-in fileheader_t
 *
 * currently omits checksum. we'll fix this when AOL breaks us, i
 * guess.
 *
 */

faim_export struct aim_fileheader_t *aim_getlisting(FILE *file) 
{
  struct aim_fileheader_t *fh;
  u_long totsize = 0, size = 0, checksum = 0xffff0000;
  short totfiles = 0;
  char *linebuf, sizebuf[9];
  
  int linelength = 1024;

  /* XXX: if we have a line longer than 1024chars, God help us. */
  if( (linebuf = (char *)calloc(1, linelength)) == NULL ) {
    faimdprintf(2, "linebuf calloc failed\n");
    return NULL;
  }  

  if(fseek(file, 0, SEEK_END) == -1) { /* use this for sanity check */
    perror("getlisting END1 fseek:");
    faimdprintf(2, "getlising fseek END1 error\n");
  }

  if(fgetpos(file, &size) == -1) {
    perror("getlisting END1 getpos:");
    faimdprintf(2, "getlising getpos END1 error\n");
  }

  if(fseek(file, 0, SEEK_SET) != 0) {
    perror("getlesting fseek(SET):");
    faimdprintf(2, "faim: getlisting: couldn't seek to beginning of listing file\n");
  }

  memset(linebuf, 0, linelength);

  size = 0;

  while(fgets(linebuf,  linelength, file)) {
    totfiles++;
    memset(sizebuf, 0, 9);

    size += strlen(linebuf);
    
    if(strlen(linebuf) < 23) {
      faimdprintf(2, "line \"%s\" too short. skipping\n", linebuf);
      continue;
    }
    if(linebuf[strlen(linebuf)-1] != '\n') {
      faimdprintf(2, "faim: OFT: getlisting -- hit EOF or line too long!\n");
    }

    memcpy(sizebuf, linebuf+17, 8);

    totsize += strtol(sizebuf, NULL, 10);
    memset(linebuf, 0, linelength);
  }   

  if(fseek(file, 0, SEEK_SET) == -1) {
    perror("getlisting END2 fseek:");
    faimdprintf(2, "getlising fseek END2 error\n");
  }  

  free(linebuf);

  /* we're going to ignore checksumming the data for now -- that
   * requires walking the whole listing.txt. it should probably be
   * done at register time and cached, but, eh. */  

  if(!(fh = (struct aim_fileheader_t*)calloc(1, sizeof(struct aim_fileheader_t))))
    return NULL;

  printf( "faim: OFT: getlisting: totfiles: %u, totsize: %lu, size: %lu\n", totfiles, totsize, size);

  fh->encrypt     = 0x0000;
  fh->compress    = 0x0000; 
  fh->totfiles    = totfiles;
  fh->filesleft   = totfiles; /* is this right ?*/
  fh->totparts    = 0x0001;
  fh->partsleft   = 0x0001;
  fh->totsize     = totsize;
  fh->size        = size; /* ls -l listing.txt */
  fh->modtime     = (int)time(NULL); /* we'll go with current time for now */
  fh->checksum    = checksum; /* XXX: checksum ! */
  fh->rfcsum      = 0x00000000;
  fh->rfsize      = 0x00000000;
  fh->cretime     = 0x00000000;
  fh->rfcsum      = 0x00000000;
  fh->nrecvd      = 0x00000000;
  fh->recvcsum    = 0x00000000;

  /*  memset(fh->idstring, 0, sizeof(fh->idstring)); */
  memcpy(fh->idstring, "OFT_Windows ICBMFT V1.1 32", sizeof(fh->idstring));
  memset(fh->idstring+strlen(fh->idstring), 0, sizeof(fh->idstring)-strlen(fh->idstring));

  fh->flags       = 0x02;
  fh->lnameoffset = 0x1a;
  fh->lsizeoffset = 0x10;

  /*  memset(fh->dummy, 0, sizeof(fh->dummy)); */
  memset(fh->macfileinfo, 0, sizeof(fh->macfileinfo));

  fh->nencode     = 0x0000; /* we need to figure out these encodings for filenames */
  fh->nlanguage   = 0x0000;

  /*  memset(fh->name, 0, sizeof(fh->name)); */
  memcpy(fh->name, "listing.txt", sizeof(fh->name));
  memset(fh->name+strlen(fh->name), 0, 64-strlen(fh->name));

  faimdprintf(2, "faim: OFT: listing fh name %s / %s\n", fh->name, (fh->name+(strlen(fh->name))));
  return fh;
}

/*
 * aim_listenestablish - create a listening socket on a port.
 * @portnum: the port number to bind to.  
 *
 * you need to call accept() when it's connected. returns your fd 
 *
 */
faim_internal int aim_listenestablish(u_short portnum)
{
#if defined(__linux__)
  /* XXX what other OS's support getaddrinfo? */
  int listenfd;
  const int on = 1;
  struct addrinfo hints, *res, *ressave;
  char serv[5];
  sprintf(serv, "%d", portnum);
  memset(&hints, 0, sizeof(struct addrinfo));
  hints.ai_flags = AI_PASSIVE;
  hints.ai_family = AF_UNSPEC;
  hints.ai_socktype = SOCK_STREAM;
  if (getaddrinfo(NULL /*any IP*/, serv, &hints, &res) != 0) {
    perror("getaddrinfo");
    return -1;
  } 
  ressave = res;
  do { 
    listenfd = socket(res->ai_family, res->ai_socktype, res->ai_protocol);    
    if (listenfd < 0)
      continue;
    setsockopt(listenfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
    if (bind(listenfd, res->ai_addr, res->ai_addrlen) == 0)
      break;
    /* success */
    close(listenfd);
  } while ( (res = res->ai_next) );

  if (!res)
    return -1;
  
  if (listen(listenfd, 1024)!=0) { 
    perror("listen");
    return -1;
  } 

  freeaddrinfo(ressave);
  return listenfd;
#else
  int listenfd;
  const int on = 1;
  struct sockaddr_in sockin;
  if ((listenfd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
    perror("socket(listenfd)");
    return -1;
  }

  if (setsockopt(listenfd, SOL_SOCKET, SO_REUSEADDR, (char *)&on, sizeof(on) != 0)) {
    perror("setsockopt(listenfd)");
    close(listenfd);
    return -1;
  } 
  
  memset(&sockin, 0, sizeof(struct sockaddr_in));
  sockin.sin_family = AF_INET;
  sockin.sin_port = htons(portnum);

  if (bind(listenfd, (struct sockaddr *)&sockin, sizeof(struct sockaddr_in)) != 0) {
    perror("bind(listenfd)");
    close(listenfd);
    return -1;
  }
  if (listen(listenfd, 4) != 0) {
    perror("listen(listenfd)");
    close(listenfd);
    return -1;
  }
  return listenfd;
#endif
} 
/*
 * aim_get_command_rendezvous - OFT equivalent of aim_get_command
 * @sess: session to work on
 * @conn: conn to pull data from 
 *
 * this reads and handles data from conn->fd. currently a little rough
 * around the edges
 */
faim_internal int aim_get_command_rendezvous(struct aim_session_t *sess, struct aim_conn_t *conn)
{
  unsigned char hdrbuf1[6];
  unsigned char *hdr = NULL;
  int hdrlen, hdrtype;
  int flags = 0;
  rxcallback_t userfunc = NULL;
  
  memset(hdrbuf1, 0, sizeof(hdrbuf1));
  faim_mutex_lock(&conn->active);
  
 /* gets locked down for the entirety */

  if(conn->subtype == AIM_CONN_SUBTYPE_OFT_GETFILE ) { 
    struct aim_filetransfer_priv *ft;
    ft = conn->priv;
    if(ft->state == 2) { 
      /* waiting on listing data */
      int ret = 0;
      char *listing;
      struct command_tx_struct *newoft;
      if(!(listing = malloc(ft->fh.size))) {
	faim_mutex_unlock(&conn->active);
	return -1;
      }

     ft->state = 0;
     if(aim_recv(conn->fd, listing, ft->fh.size) != ft->fh.size)	
       faimdprintf(2, "OFT get: file %s was short. (0x%lx)\n", ft->fh.name, ft->fh.size);

     if(!(newoft = aim_tx_new(AIM_FRAMETYPE_OFT, 0x120b, conn, 0))) {
       faimdprintf(2, "faim: aim_get_command_rendezvous: getfile listing: tx_new OFT failed\n");
       faim_mutex_unlock(&conn->active);
       free(listing);
       aim_conn_close(conn);
       return -1;
     }

     newoft->lock = 1;

     memcpy(newoft->hdr.oft.magic, "OFT2", 4);
     newoft->hdr.oft.hdr2len = 0x100 - 8;
     
     /* this is icky. */
     ft->fh.nrecvd = ft->fh.size;
     ft->fh.recvcsum = ft->fh.checksum;
     ft->fh.flags = 0;
     
     if (!(newoft->hdr.oft.hdr2 = (char *)calloc(1,newoft->hdr.oft.hdr2len))) {
       newoft->lock = 0;
       aim_tx_destroy(newoft);
       free(listing);
       faim_mutex_unlock(&conn->active);
       return -1;
     }
     
     if(!(aim_oft_buildheader((unsigned char *)newoft->hdr.oft.hdr2, &(ft->fh))))
       printf("eek! bh fail listing\n");

     /* send the 120b	*/
     newoft->lock = 0;
     aim_tx_enqueue(sess, newoft);
     if( (userfunc = aim_callhandler(conn, AIM_CB_FAM_OFT, AIM_CB_OFT_GETFILELISTING)) )
       ret = userfunc(sess, NULL, conn, ft, listing);
     
     faim_mutex_unlock(&conn->active);
     free(listing);
     return ret;
   }
   if(ft->state == 3) { 
     /* waiting on file data */
     if( (userfunc = aim_callhandler(conn, AIM_CB_FAM_OFT, AIM_CB_OFT_GETFILERECIEVE)) )  {
       faim_mutex_unlock(&conn->active);
       return userfunc(sess, NULL, conn, ft);
     }
     faim_mutex_unlock(&conn->active);
     return 0;
   }
 }
 
 if ( (hdrlen = aim_recv(conn->fd, hdrbuf1, 6)) < 6) {
   faimdprintf(2, "faim: rend: read error (fd: %i) %02x%02x%02x%02x%02x%02x (%i)\n", 
	       conn->fd, hdrbuf1[0],hdrbuf1[1],hdrbuf1[2],hdrbuf1[3],hdrbuf1[4],hdrbuf1[5],hdrlen);
   faim_mutex_unlock(&conn->active);
   if(hdrlen < 0)
     perror("read");
   else { /* disconnected */
     switch(conn->subtype) { 
     case AIM_CONN_SUBTYPE_OFT_DIRECTIM: { 
       /* XXX: clean up cookies here ? */
       struct aim_directim_priv *priv = NULL;
       if(!(priv = (struct aim_directim_priv *)conn->priv) )
	 return -1;
       
       aim_uncachecookie(sess, priv->cookie, AIM_COOKIETYPE_OFTIM);
       if ( (userfunc = aim_callhandler(conn, AIM_CB_FAM_OFT, AIM_CB_OFT_DIRECTIMDISCONNECT)) ) {
	 aim_conn_close(conn);
	 return userfunc(sess, NULL, conn, priv->sn);
       }
       break;
     } 
     case AIM_CONN_SUBTYPE_OFT_GETFILE: {
       struct aim_filetransfer_priv *priv;
       if(!(priv = (struct aim_filetransfer_priv *)conn->priv))
	 return -1;
       aim_uncachecookie(sess, priv->cookie, AIM_COOKIETYPE_OFTGET);
       if ( (userfunc = aim_callhandler(conn, AIM_CB_FAM_OFT, AIM_CB_OFT_GETFILEDISCONNECT)) ) {
	 aim_conn_close(conn);
	 return userfunc(sess, NULL, conn, priv->sn);
       }
       break;
     }
     case AIM_CONN_SUBTYPE_OFT_SENDFILE: {
       struct aim_filetransfer_priv *priv;
       if(!(priv = (struct aim_filetransfer_priv *)conn->priv))
	 return -1;
       aim_uncachecookie(sess, priv->cookie, AIM_COOKIETYPE_OFTSEND);
       if ( (userfunc = aim_callhandler(conn, AIM_CB_FAM_OFT, AIM_CB_OFT_SENDFILEDISCONNECT)) ) { 
	 aim_conn_close(conn);
	 return userfunc(sess, NULL, conn, priv->sn);
       }
       break;
     } 
     }

     aim_conn_close(conn);
     return -1;
   }
 }

 hdrlen = aimutil_get16(hdrbuf1+4);
 hdrlen -= 6;

 if (!(hdr = malloc(hdrlen))) { 
   faim_mutex_unlock(&conn->active);
   return -1;
 }

 if (aim_recv(conn->fd, hdr, hdrlen) < hdrlen) {
   perror("read");
   faimdprintf(2,"faim: rend: read2 error on %d (%d)\n", conn->fd, hdrlen);
   free(hdr);
   faim_mutex_unlock(&conn->active);
   aim_conn_close(conn);
   return -1;
   }
 hdrtype = aimutil_get16(hdr);
 printf("\tgot 0x%04x", hdrtype);
 switch (hdrtype) {
 case 0x0001: {    /* directim */
   int payloadlength = 0;
   char *snptr = NULL;
   struct aim_directim_priv *priv;
   int i;

   if(!(priv = (struct aim_directim_priv *)calloc(1, sizeof(struct aim_directim_priv)))) {
     faim_mutex_unlock(&conn->active);
     return -1;
   }
   
   payloadlength = aimutil_get32(hdr+22);
   flags = aimutil_get16(hdr+32);
   snptr = (char *)hdr+38;
   strncpy(priv->sn, snptr, MAXSNLEN);

   faimdprintf(2, "faim: OFT frame: %04x / %04x / %04x / %s\n", hdrtype, payloadlength, flags, snptr);

   if (flags == 0x000e) { 
     faim_mutex_unlock(&conn->active);
     if ( (userfunc = aim_callhandler(conn, AIM_CB_FAM_OFT, AIM_CB_OFT_DIRECTIMTYPING)) )
       return userfunc(sess, NULL, snptr);
   } else
     if ((flags == 0x0000) && payloadlength) { 
       unsigned char *msg;
       if(! (msg = calloc(1, payloadlength+1)) ) {
	 faim_mutex_unlock(&conn->active);
	 return -1;
       }
       if (aim_recv(conn->fd, msg, payloadlength) < payloadlength) {
	 perror("read");
	 printf("faim: rend: read3 error\n");
	 free(msg);
	 faim_mutex_unlock(&conn->active);
	 aim_conn_close(conn);
	 return -1;
       }
       faim_mutex_unlock(&conn->active);
       msg[payloadlength] = 0x00;
       faimdprintf(2, "faim: directim: %s/%04x/%04x/%s\n", snptr, payloadlength, flags, msg);
       if ( (userfunc = aim_callhandler(conn, AIM_CB_FAM_OFT, AIM_CB_OFT_DIRECTIMINCOMING)) )
	 i = userfunc(sess, NULL, conn, snptr, msg);
       free(msg);
       return i;
     }
   break;
 }
 case 0x1108: { /* getfile listing.txt incoming tx->rx */
   struct aim_filetransfer_priv *ft;
   struct aim_fileheader_t *fh;
   struct aim_msgcookie_t *cook;
   struct command_tx_struct *newoft;
   faimdprintf(2,"faim: rend: fileget 0x1108\n");
   fh = aim_oft_getfh(hdr);
   faim_mutex_unlock(&conn->active);
   if(!(cook = aim_checkcookie(sess, fh->bcookie, AIM_COOKIETYPE_OFTGET))) {
     faim_mutex_unlock(&conn->active);
     free(fh);
     return -1;
   }
   ft = cook->data;
   ft->state = 2;

   /* we're waaaaiiiting.. for listing.txt */

   memcpy(&(ft->fh), fh, sizeof(struct aim_fileheader_t));
   aim_cachecookie(sess, cook);
   free(fh);

   if(!(newoft = aim_tx_new(AIM_FRAMETYPE_OFT, 0x1209, conn, 0))) {
     aim_conn_close(conn);
     return -1;
   }

   memcpy(newoft->hdr.oft.magic, "OFT2", 4);
   newoft->hdr.oft.hdr2len = 0x100 - 8;

   if (!(newoft->hdr.oft.hdr2 = (char *)calloc(1,newoft->hdr.oft.hdr2len))) {
     newoft->lock = 0;
     aim_tx_destroy(newoft);
     return -1;
   }

   if(!(aim_oft_buildheader((unsigned char *)newoft->hdr.oft.hdr2, &(ft->fh)))) {
     newoft->lock = 0;
     aim_tx_destroy(newoft);
     return -1;
   }

   newoft->lock = 0;
   aim_tx_enqueue(sess, newoft);
   break;
   
 } 
 case 0x1209: { /* get file listing ack rx->tx */
   struct aim_filetransfer_priv *ft;
   struct aim_fileheader_t *fh;
   struct aim_msgcookie_t *cook;
   int ret;

   fh = aim_oft_getfh(hdr);
   faim_mutex_unlock(&conn->active);

   if(!(cook = aim_checkcookie(sess, fh->bcookie, AIM_COOKIETYPE_OFTGET)))
     faimdprintf(2, "shit, no cookie in 0x1209. (%i/%s)going to crash..\n", 
		 AIM_COOKIETYPE_OFTGET, fh->bcookie);

   ft = cook->data;   

   if(ft->fh.size != fh->size)
     faimdprintf(2, "hrm. ft->fh.size (%ld) != fh->size (%ld). um. using ft->fh.size\n", 
		 ft->fh.size, fh->size);

   
   if ( (userfunc = aim_callhandler(conn, AIM_CB_FAM_OFT, AIM_CB_OFT_GETFILELISTINGREQ)))
     ret = userfunc(sess, NULL, conn, fh);   

   faimdprintf(2, "faim: get_command_rendezvous: hit end of 1209\n");

   free(fh);

   return ret;

   break;
 }
 case 0x120b: {    /* getfile listing.txt rx confirm */
   struct aim_filetransfer_priv *ft;
   struct aim_msgcookie_t *cook;
   struct aim_fileheader_t *fh;

   fh = aim_oft_getfh(hdr);
   faim_mutex_unlock(&conn->active);

   if(!(cook = aim_checkcookie(sess, fh->bcookie, AIM_COOKIETYPE_OFTGET)))     {
     free(fh);
     return -1;
   }

   ft = cook->data;
   aim_cachecookie(sess, cook);
   free(fh);

   /* XXX: call listing.txt rx confirm */
   break;
 }
 case 0x120c: { /* getfile file request */
   struct aim_filetransfer_priv *ft;
   struct aim_msgcookie_t *cook;
   struct aim_fileheader_t *fh;
   struct command_tx_struct *newoft;
   int i;

   fh = aim_oft_getfh(hdr);
   faim_mutex_unlock(&conn->active);

   if(!(cook = aim_checkcookie(sess, fh->bcookie, AIM_COOKIETYPE_OFTGET)))
     return -1;

   ft = cook->data;
   memcpy(&(ft->fh), fh, sizeof(struct aim_fileheader_t));
   free(fh);

   aim_cachecookie(sess, cook);

   faimdprintf(2, "faim: fileget: %s seems to want %s\n", ft->sn, ft->fh.name);

   if( (userfunc = aim_callhandler(conn, AIM_CB_FAM_OFT, AIM_CB_OFT_GETFILEFILEREQ)) )
     i = userfunc(sess, NULL, conn, &(ft->fh), cook->cookie);

   if(i < 0)
     return -1;

   if(!(newoft = aim_tx_new(AIM_FRAMETYPE_OFT, 0x0101, conn, 0))) {
     faimdprintf(2, "faim: send_final_transfer: tx_new OFT failed\n");
     return -1;
   }

   newoft->lock = 1;
   memcpy(newoft->hdr.oft.magic, "OFT2", 4);
   newoft->hdr.oft.hdr2len = 0x100 - 8;

   if (!(newoft->hdr.oft.hdr2 = calloc(1,newoft->hdr.oft.hdr2len))) {
     newoft->lock = 0;
     aim_tx_destroy(newoft);
     return -1;
   } 

   /* protocol BS: nrecvd, recvcsum to 0, flags to 0x20. */
   ft->fh.nrecvd = 0;
   ft->fh.recvcsum = 0;
   ft->fh.flags = 0x20;

   aim_oft_buildheader((unsigned char *)newoft->hdr.oft.hdr2, &(ft->fh));

   newoft->lock = 0;
   aim_tx_enqueue(sess, newoft);

   faimdprintf(2, "faim: OFT: OFT file header enqueued.\n");

   return i;

   break;
 }
 case 0x0101: {    /* getfile: sending data  */
   struct aim_fileheader_t *fh;
   struct aim_filetransfer_priv *ft;
   struct aim_msgcookie_t *cook;
   struct command_tx_struct *newoft;

   fh = aim_oft_getfh(hdr);
   faim_mutex_unlock(&conn->active);

   if(!(cook = aim_checkcookie(sess, fh->bcookie, AIM_COOKIETYPE_OFTGET))) {
     printf("fucking no cookie\n");
     free(fh);
     return -1;
   }
   free(fh);

   ft = cook->data;

   ft->state = 3;
   aim_cachecookie(sess, cook);

   faimdprintf(2, "faim: fileget: %s seems to want to send %s\n", ft->sn, ft->fh.name);

   if(!(newoft = aim_tx_new(AIM_FRAMETYPE_OFT, 0x0202, conn, 0))) {
     aim_conn_close(conn);
     faimdprintf(2, "faim: send_final_transfer: tx_new OFT failed\n");
     return -1;
   }

   newoft->lock = 1;
   memcpy(newoft->hdr.oft.magic, "OFT2", 4);

   newoft->hdr.oft.hdr2len = 0x100 - 8;

   if (!(newoft->hdr.oft.hdr2 = calloc(1,newoft->hdr.oft.hdr2len))) {
     newoft->lock = 0;
     aim_tx_destroy(newoft);
     return -1;
   }

   aim_oft_buildheader((unsigned char *)newoft->hdr.oft.hdr2, &(ft->fh));

   newoft->lock = 0;
   aim_tx_enqueue(sess, newoft);

   faimdprintf(2, "faim: OFT: OFT 0x0202 enqueued.\n");

   if( (userfunc = aim_callhandler(conn, AIM_CB_FAM_OFT, AIM_CB_OFT_GETFILEFILEREQ)) == NULL)
     return 1;

   break;
 }
 case 0x0202: {    /* get file: ready to recieve data */
   struct aim_fileheader_t *fh;
   struct aim_filetransfer_priv *ft;
   struct aim_msgcookie_t *cook;
   int ret = 1;

   fh = aim_oft_getfh(hdr);
   faim_mutex_unlock(&conn->active);

   if(!(cook = aim_checkcookie(sess, fh->bcookie, AIM_COOKIETYPE_OFTGET))) {
     free(fh);
     return -1;
   }
   
   ft = cook->data;

   faimdprintf(2, "faim: get_rend: looks like we're ready to send data.(oft 0x0202)\n");

   if ( (userfunc = aim_callhandler(conn, AIM_CB_FAM_OFT, AIM_CB_OFT_GETFILEFILESEND)) )
     ret = userfunc(sess, NULL, conn, fh);

   free(fh);

   return ret;
   break;
 }
 case 0x0204: {    /* get file: finished. close it up */
   int i;
   struct aim_fileheader_t *fh;

   fh = aim_oft_getfh(hdr);
   faim_mutex_unlock(&conn->active);

   faimdprintf(2, "faim: get_rend: looks like we're done with a transfer (oft 0x0204)\n");

   if ( (userfunc = aim_callhandler(conn, AIM_CB_FAM_OFT, AIM_CB_OFT_GETFILECOMPLETE)) )
     i = userfunc(sess, NULL, conn, fh);
   else 
     i = 1;

   if(conn)
     aim_conn_close(conn);

   free(fh);

   return i;
   break;
 }
 default: { 
	faimdprintf(2,"faim: OFT frame: uknown type %04x\n", hdrtype);
	faim_mutex_unlock(&conn->active);
	break;
 } 
 } /* switch */
 free(hdr);
 return 0;
}
 
/*
 * aim_oft_getfh - extracts a aim_fileheader_t from buffer hdr.
 * @hdr: buffer to extract header from  
 *
 * returns pointer to struct on success; %NULL on error.  
 *
 */
static struct aim_fileheader_t *aim_oft_getfh(unsigned char *hdr) 
{
  struct aim_fileheader_t *fh;
  int i, j;
  if(!(fh = calloc(1, sizeof(struct aim_fileheader_t))))
    return NULL;
  
  /* [0] and [1] are the type. we can ignore those here. */
  i = 2;
  for(j = 0; j < 8; j++, i++)
    fh->bcookie[j] = hdr[i];
  fh->encrypt = aimutil_get16(hdr+i);
  i += 2;
  fh->compress = aimutil_get16(hdr+i);
  i += 2;
  fh->totfiles = aimutil_get16(hdr+i);
  i += 2;
  fh->filesleft = aimutil_get16(hdr+i);
  i += 2;
  fh->totparts = aimutil_get16(hdr+i);
  i += 2;
  fh->partsleft = aimutil_get16(hdr+i);
  i += 2;
  fh->totsize = aimutil_get32(hdr+i);
  i += 4;
  fh->size = aimutil_get32(hdr+i);
  i += 4;
  fh->modtime = aimutil_get32(hdr+i);
  i += 4;
  fh->checksum = aimutil_get32(hdr+i);
  i += 4;
  fh->rfrcsum = aimutil_get32(hdr+i);
  i += 4;
  fh->rfsize = aimutil_get32(hdr+i);
  i += 4;
  fh->cretime = aimutil_get32(hdr+i);
  i += 4;
  fh->rfcsum = aimutil_get32(hdr+i);
  i += 4;
  fh->nrecvd = aimutil_get32(hdr+i);
  i += 4;
  fh->recvcsum = aimutil_get32(hdr+i);
  i += 4;
  memcpy(fh->idstring, hdr+i, 32);
  i += 32;
  fh->flags = aimutil_get8(hdr+i);
  i += 1;
  fh->lnameoffset = aimutil_get8(hdr+i);
  i += 1;
  fh->lsizeoffset = aimutil_get8(hdr+i);
  i += 1;
  memcpy(fh->dummy, hdr+i, 69);
  i += 69;
  memcpy(fh->macfileinfo, hdr+i, 16);
  i += 16;
  fh->nencode = aimutil_get16(hdr+i);
  i += 2;
  fh->nlanguage = aimutil_get16(hdr+i);
  i += 2;
  memcpy(fh->name, hdr+i, 64);
  i += 64;
  return fh;
} 

/*
 * aim_oft_checksum - calculate oft checksum of buffer
 * @buffer: buffer of data to checksum
 * @bufsize: size of buffer
 * @checksum: pointer to integer to place result in (pointer!) 
 
 *
 * note that checksum is a pointer. checksum should be filled with
 * 0xFFFF0000 for each new file; you can have this checksum chunks of
 * files in series if you just call it repeatedly in a for(; ; ) loop
 * and don't reset the checksum between each call. and you thought we
 * didn't care about you and your pathetic client's meomry footprint
 * ;^) 
 *
 */
faim_export int aim_oft_checksum(char *buffer, int bufsize, int *checksum){ short check0, check1;
 int i;
 check0 = ((*checksum & 0xFF000000) >> 16);
 check1 = ((*checksum & 0x00ff0000) >> 16);
 for(i = 0; i < bufsize; i++) {
   if(i % 2) { /* use check1 -- second byte */
     if ( (short)buffer[i] > check1 ) { /* wrapping */
       check1 += 0x100;  /* this is a cheap way to wrap */

       /* if we're wrapping, decrement the other one */
       /* XXX: check this corner case */
       if(check0 == 0) 
	 check0 = 0x00ff;
       else 
	 check0--;
     } 
     check1 -= buffer[i];
   } else { /* use check0 -- first byte  */
     if ( (short)buffer[i] > check0 ) { /* wrapping */
       check0 += 0x100;       /* this is a cheap way to wrap */
  
       /* if we're wrapping, decrement the other one */
	 /* XXX: check this corner case */
       if(check1 == 0) 
	 check1 = 0x00ff;
       else 
	 check1--;
     } 
     check0 -= buffer[i];
     } 
 }

 if(check0 > 0xff || check1 > 0xff)  { 
     /* they shouldn't be able to do this. error! */
   faimdprintf(2, "check0 or check1 is too high: 0x%04x, 0x%04x\n", check0, check1);
     return -1;
 } 

 /* grab just the lowest byte; this should be clean, but just in
    case */
 check0 &= 0xff;
 check1 &= 0xff;

 *checksum = ((check0 * 0x1000000) + (check1 * 0x10000));
 return *checksum;
} 

/*
 * aim_oft_buildheader - fills a buffer with network-order fh data
 * @dest: buffer to fill -- pre-alloced
 * @fh: fh to get data from  
 *
 * returns length written; -1 on error.
 * DOES NOT DO BOUNDS CHECKING!
 *
 */
faim_internal int aim_oft_buildheader(unsigned char *dest,struct aim_fileheader_t *fh) 
{ 
  int i, curbyte;
  if(!dest || !fh)
    return -1;
  curbyte = 0;
  for(i = 0; i < 8; i++) 
    curbyte += aimutil_put8(dest+curbyte, fh->bcookie[i]);
  curbyte += aimutil_put16(dest+curbyte, fh->encrypt);
  curbyte += aimutil_put16(dest+curbyte, fh->compress);
  curbyte += aimutil_put16(dest+curbyte, fh->totfiles);
  curbyte += aimutil_put16(dest+curbyte, fh->filesleft);
  curbyte += aimutil_put16(dest+curbyte, fh->totparts);
  curbyte += aimutil_put16(dest+curbyte, fh->partsleft);
  curbyte += aimutil_put32(dest+curbyte, fh->totsize);
  curbyte += aimutil_put32(dest+curbyte, fh->size);
  curbyte += aimutil_put32(dest+curbyte, fh->modtime);
  curbyte += aimutil_put32(dest+curbyte, fh->checksum);
  curbyte += aimutil_put32(dest+curbyte, fh->rfrcsum);
  curbyte += aimutil_put32(dest+curbyte, fh->rfsize);
  curbyte += aimutil_put32(dest+curbyte, fh->cretime);
  curbyte += aimutil_put32(dest+curbyte, fh->rfcsum);
  curbyte += aimutil_put32(dest+curbyte, fh->nrecvd);
  curbyte += aimutil_put32(dest+curbyte, fh->recvcsum);
  memcpy(dest+curbyte, fh->idstring, 32);
  curbyte += 32;
  curbyte += aimutil_put8(dest+curbyte, fh->flags);
  curbyte += aimutil_put8(dest+curbyte, fh->lnameoffset);
  curbyte += aimutil_put8(dest+curbyte, fh->lsizeoffset);
  memcpy(dest+curbyte, fh->dummy, 69);
  curbyte += 69;
  memcpy(dest+curbyte, fh->macfileinfo, 16);
  curbyte += 16;
  curbyte += aimutil_put16(dest+curbyte, fh->nencode);
  curbyte += aimutil_put16(dest+curbyte, fh->nlanguage);
  memset(dest+curbyte, 0x00, 64);
  memcpy(dest+curbyte, fh->name, 64);

  /* XXX: Filenames longer than 64B  */
  curbyte += 64;
  return curbyte;
}
#if 0 
/*
* aim_getfile_send - send a FULL file down (ie: blocking; that is: DON'T USE IT, use send_chunk below.)
* @conn: the OFT connection to shove the data down,
* @tosend: is the FILE
* for the file to send
* @fh: the filled-in fh value 

*
* returns -1 on error, 1 on success. This sends the whold file and
* blocks, so it will totally mess you up if you use it. use the
* send_chunk below and work out a schduling setup or some such. 

*
*/
faim_export int aim_getfile_send(struct aim_conn_t *conn, FILE *tosend, struct aim_fileheader_t *fh)
{ 
  int pos, bufpos, i;
  const int bufsize = 4096;
  char *buf;
  
 /* sanity checks
  */

 if(conn->type != AIM_CONN_TYPE_RENDEZVOUS || conn->subtype != AIM_CONN_SUBTYPE_OFT_GETFILE)
   { faimdprintf(1, "getfile_send: conn->type(0x%04x) != RENDEZVOUS or conn->subtype(0x%04x) != GETFILE\n", conn->type, conn->subtype);
   return -1;
   }
 if(!tosend)
   { faimdprintf(1, "getfile_send: file pointer isn't valid\n");
   return -1;
   }
 if(!fh)
   { faimdprintf(1, "getfile_send: fh isn't valid\n");
   return -1;
   } 
 /* real code
  */

 if(!(buf = (char *)calloc(1, bufsize)))
   { perror("faim: getfile_send: calloc:");
   faimdprintf(2, "getfile_send calloc error\n");
   return -1;
   } pos = 0;
 if( fseek(tosend, 0, SEEK_SET) == -1)
   { perror("faim: getfile_send: fseek:");
   faimdprintf(2, "getfile_send fseek error\n");
   } faimdprintf(2, "faim: getfile_send: using %i byte blocks\n", bufsize);
 for(pos = 0;
     pos < fh->size;
     pos++) { bufpos = pos % bufsize;
     if(bufpos == 0 && pos > 0)
       { 
	 /* filled our buffer. spit it across the wire
	  */

	 if ( (i = send(conn->fd, buf, bufsize, 0)) != bufsize )
	   { perror("faim: getfile_send: write1: ");
	   faimdprintf(1, "faim: getfile_send: whoopsy, didn't write it all...\n");
	   free(buf);
	   return -1;
	   } }
     if( (buf[bufpos] = fgetc(tosend)) == EOF)
       {
	 if(pos != fh->size)
	   { printf("faim: getfile_send: hrm... apparent early EOF at pos 0x%x of 0x%lx\n", pos, fh->size);
	   faimdprintf(1, "faim: getfile_send: hrm... apparent early EOF at pos 0x%lx of 0x%lx\n", pos, fh->size);
	   free(buf);
	   return -1;
	   } } }
 if( (i = send(conn->fd, buf, bufpos+1, 0)) != (bufpos+1))
   { perror("faim: getfile_send: write2: ");
   faimdprintf(1, "faim: getfile_send cleanup: whoopsy, didn't write it all...\n");
   free(buf);
   return -1;
   } free(buf);
 fclose(tosend);
 return 1;
}
 
/*
* aim_getfile_send_chunk - send a chunk of a file down a conn
* @conn: the OFT connection to shove the data down,
* @tosend: the buffer to send
* @fh: the filled-in fh value
* @pos: the position to start at (see below)
* @bufsize: the size of the chunk to send 

*
* returns -1 on error, new pos on success.
* Notes on usage:
* You don't really have to keep track of pos if you don't want
* to. just always call with -1 for pos, and it'll use the one
* contained within the FILE
*. 

*
* if (pos + chunksize > fh->size), we only send as much data as we
* can get (ie: up to fh->size. 

*
* the value of pos: at beginning should be 0, after 5 bytes are sent
* should be 5); -1 for "don't seek" 

*
* GOING TO BE CHANGED TO USE unsigned char
* BUFFERS!!!
*/
faim_export int aim_getfile_send_chunk(struct aim_conn_t *conn, FILE *tosend, struct aim_fileheader_t *fh, int pos, int bufsize)
{
 int bufpos;
 char *buf;

 /* sanity checks
  */

 if(conn->type != AIM_CONN_TYPE_RENDEZVOUS || conn->type != AIM_CONN_SUBTYPE_OFT_GETFILE)
   { faimdprintf(1, "faim: getfile_send_chunk: conn->type(0x%04x) != RENDEZVOUS or conn->subtype(0x%04x) != GETFILE\n", conn->type, conn->subtype);
   return -1;
   }
 if(!tosend)
   { faimdprintf(1, "faim: getfile_send_chunk: file pointer isn't valid\n");
   return -1;
   }
 if(!fh)
   { faimdprintf(1, "faim: getfile_send_chunk: fh isn't valid\n");
   return -1;
   } 
 /* real code
  */

 if(!(buf = (char *)calloc(1, bufsize)))
   { perror("faim: getfile_send_chunk: calloc:");
   faimdprintf(2, "faim: getfile_send_chunk calloc error\n");
   return -1;
   }
 if(pos != -1)
   {
     if( fseek(tosend, pos, SEEK_SET) == -1)
       { perror("faim: getfile_send_chunk: fseek:");
       faimdprintf(2, "faim: getfile_send_chunk fseek error\n");
       } } faimdprintf(2, "faim: getfile_send_chunk: using %i byte blocks\n", bufsize);
 for(bufpos = 0;
     pos < fh->size;
     bufpos++, pos++) {
   if( (buf[bufpos] = fgetc(tosend)) == EOF)
     {
       if(pos != fh->size)
	 { faimdprintf(1, "faim: getfile_send_chunk: hrm... apparent early EOF at pos 0x%x of 0x%x\n", pos, fh->size);
	 free(buf);
	 return -1;
	 } } }
 if( send(conn->fd, buf, bufpos+1, 0) != (bufpos+1))
   { faimdprintf(1, "faim: getfile_send_chunk cleanup: whoopsy, didn't write it all...\n");
   free(buf);
   return -1;
   } free(buf);
 return (pos + bufpos);
}
#endif 
/*
* aim_tx_destroy - free's tx_command_t's
* @command: the command to free 

*
* if command is locked, doesn't free.
* returns -1 on error (locked struct); 0 on success. 

*
*/
faim_internal int aim_tx_destroy(struct command_tx_struct *command){
  if(command->lock)
    return -1;
  if(command->data)
    free(command->data);
  if (command->hdrtype == AIM_FRAMETYPE_OFT && command->hdr.oft.hdr2)
    free(command->hdr.oft.hdr2);
  free(command);
  return 0;
} 

/*
 * aim_getfile_intitiate - For those times when we want to open up the getfile dialog ourselves.
 * @sess: your session,
 * @conn: the BOS conn,
 * @destsn is the SN to connect to.
 */
faim_export struct aim_conn_t *aim_getfile_initiate(struct aim_session_t *sess, struct aim_conn_t *conn, char *destsn)
{ 
  struct command_tx_struct *newpacket;
 struct aim_conn_t *newconn;
 struct aim_filetransfer_priv *priv;
 struct aim_msgcookie_t *cookie;
 int curbyte, i, listenfd;
 short port = 4443;
 struct hostent *hptr;
 struct utsname myname;
 char cap[16];
 char d[4];
 
 /* Open our socket */

 if( (listenfd = aim_listenestablish(port)) == -1)
   return NULL;

 /* get our local IP */

 if(uname(&myname) < 0)
   return NULL;
 if( (hptr = gethostbyname(myname.nodename)) == NULL)
   return NULL;
 memcpy(&d, hptr->h_addr_list[0], 4);

 /* XXX: this probably isn't quite kosher, but it works */
 aim_putcap(cap, 16, AIM_CAPS_GETFILE);

 /* create the OSCAR packet */

 if (!(newpacket = aim_tx_new(AIM_FRAMETYPE_OSCAR, 0x0002, conn, 10+8+2+1+strlen(destsn)+4+4+0x42)))
   return NULL;
 newpacket->lock = 1;

 /* lock struct */
 curbyte = 0;
 curbyte += aim_putsnac(newpacket->data+curbyte, 0x0004, 0x0006, 0x0000, sess->snac_nextid);

 /* XXX: check the cookie before commiting to using it */

 /* Generate a random message cookie
  * This cookie needs to be alphanumeric and NULL-terminated to be TOC-compatible. */
 for (i=0; i<7; i++) 
   curbyte += aimutil_put8(newpacket->data+curbyte, 0x30 + ((u_char) random() % 10));

 curbyte += aimutil_put8(newpacket->data+curbyte, 0x00);

 /* grab all the data for cookie caching. */

 cookie = (struct aim_msgcookie_t *)calloc(1, sizeof(struct aim_msgcookie_t));
 memcpy(cookie->cookie, newpacket->data+curbyte-8, 8);
 cookie->type = AIM_COOKIETYPE_OFTGET;

 priv = (struct aim_filetransfer_priv *)calloc(1, sizeof(struct aim_filetransfer_priv));
 memcpy(priv->cookie, cookie, 8);
 memcpy(priv->sn, destsn, sizeof(priv->sn));
 memcpy(priv->fh.name, "listing.txt", strlen("listing.txt"));
 priv->state = 1;
 cookie->data = priv;
 conn->priv = priv;
 aim_cachecookie(sess, cookie);

 /* cache da cookie */
 
 /* Channel ID */
 curbyte += aimutil_put16(newpacket->data+curbyte,0x0002);

 /* Destination SN (prepended with byte length) */
 curbyte += aimutil_put8(newpacket->data+curbyte,strlen(destsn));
 curbyte += aimutil_putstr(newpacket->data+curbyte, destsn, strlen(destsn));
 curbyte += aimutil_put16(newpacket->data+curbyte, 0x0003);
 curbyte += aimutil_put16(newpacket->data+curbyte, 0x0000);

 /* enTLV start */
 curbyte += aimutil_put16(newpacket->data+curbyte, 0x0005);
 curbyte += aimutil_put16(newpacket->data+curbyte, 0x0042);

 /* Flag data / ICBM Parameters? */
 curbyte += aimutil_put8(newpacket->data+curbyte, 0x00);
 curbyte += aimutil_put8(newpacket->data+curbyte, 0x00);

 /* Cookie */
 curbyte += aimutil_putstr(newpacket->data+curbyte, (char *)cookie, 8);

 /* Capability String */
 curbyte += aimutil_putstr(newpacket->data+curbyte, (char *)cap, 0x10);

 /* 000a/0002 : 0001 */
 curbyte += aimutil_put16(newpacket->data+curbyte, 0x000a);
 curbyte += aimutil_put16(newpacket->data+curbyte, 0x0002);
 curbyte += aimutil_put16(newpacket->data+curbyte, 0x0001);

 /* 0003/0004: IP address */
 curbyte += aimutil_put16(newpacket->data+curbyte, 0x0003);
 curbyte += aimutil_put16(newpacket->data+curbyte, 0x0004);
 for(i = 0; i < 4; i++)
   curbyte += aimutil_put8(newpacket->data+curbyte, d[i]);

 /* already in network byte order  */
 
 /* 0005/0002: Port */
 curbyte += aimutil_put16(newpacket->data+curbyte, 0x0005);
 curbyte += aimutil_put16(newpacket->data+curbyte, 0x0002);
 curbyte += aimutil_put16(newpacket->data+curbyte, port);

 /* 000f/0000: ?? */
 curbyte += aimutil_put16(newpacket->data+curbyte, 0x000f);
 curbyte += aimutil_put16(newpacket->data+curbyte, 0x0000);

 /* 2711/000c: ?? */
 curbyte += aimutil_put16(newpacket->data+curbyte, 0x2711);
 curbyte += aimutil_put16(newpacket->data+curbyte, 0x000c);
 curbyte += aimutil_put32(newpacket->data+curbyte, 0x00120001);

 for(i = 0; i < 0x000c - 4; i++)
   curbyte += aimutil_put8(newpacket->data+curbyte, 0x00);

 newpacket->commandlen = curbyte;
 newpacket->lock = 0;
 aim_tx_enqueue(sess, newpacket);

 /* allocate and set up our connection */

 i = fcntl(listenfd, F_GETFL, 0);
 fcntl(listenfd, F_SETFL, i | O_NONBLOCK);
 newconn = aim_newconn(sess, AIM_CONN_TYPE_RENDEZVOUS_OUT, NULL);

 if (!newconn){ 
   perror("aim_newconn");
   return NULL;
 }

 newconn->fd = listenfd;
 newconn->subtype = AIM_CONN_SUBTYPE_OFT_GETFILE;
 newconn->priv = priv;
 faimdprintf(2,"faim: listening (fd = %d, unconnected)\n", newconn->fd);

 return newconn;
}
 
/*
 * aim_oft_getfile_request - request a particular file over an established getfile connection
 * @sess: your session
 * @conn: the established OFT getfile connection
 * @name: filename to request
 * @size: size of the file 
 *
 */
faim_export int aim_oft_getfile_request(struct aim_session_t *sess, struct aim_conn_t *conn, const unsigned char *name, const int size)
{
  struct command_tx_struct *newoft;
  struct aim_filetransfer_priv *ft;
  if(!sess || !conn || !conn->priv || !name)
    return 0;

 if(!(newoft = aim_tx_new(AIM_FRAMETYPE_OFT, 0x120c, conn, 0))) {
   faimdprintf(2, "faim: aim_accepttransfer: tx_new OFT failed\n");
   return -1;
 }

 newoft->lock = 1;

 memcpy(newoft->hdr.oft.magic, "OFT2", 4);
 newoft->hdr.oft.hdr2len = 0x100 - 8;

 ft = (struct aim_filetransfer_priv *)conn->priv;
 ft->fh.filesleft = 1;
 ft->fh.totfiles = 1;
 ft->fh.totparts = 1;
 ft->fh.partsleft = 1;
 ft->fh.totsize = size;
 ft->fh.size = size;
 ft->fh.checksum = 0;
 memcpy(ft->fh.name, name, strlen(name));
 memset(ft->fh.name+strlen(name), 0, 1);

 if (!(newoft->hdr.oft.hdr2 = (char *)calloc(1,newoft->hdr.oft.hdr2len))) {
   newoft->lock = 0;
   aim_tx_destroy(newoft);
   return -1;
 }

 if(!(aim_oft_buildheader((unsigned char *)newoft->hdr.oft.hdr2, &(ft->fh)))) {
   newoft->lock = 0;
   aim_tx_destroy(newoft);
   return -1;
 }

 newoft->lock = 0;

 aim_tx_enqueue(sess, newoft);
 return 0;
}
 
/*
 * aim_oft_getfile_ack - acknowledge a getfile download as complete
 * @sess: your session
 * @conn: the getfile conn to send the ack over 
 *
 * call this function after you have read all the data in a particular
 * filetransfer 
 *
 */
faim_export int aim_oft_getfile_ack(struct aim_session_t *sess, struct aim_conn_t *conn) {
  struct command_tx_struct *newoft;
  struct aim_filetransfer_priv *ft;

  if(!sess || !conn || !conn->priv)
    return -1;

  if(!(newoft = aim_tx_new(AIM_FRAMETYPE_OFT, 0x0202, conn, 0))) {
    faimdprintf(2, "faim: aim_accepttransfer: tx_new OFT failed\n");
    return -1;
  } 

  newoft->lock = 1;

  memcpy(newoft->hdr.oft.magic, "OFT2", 4);
  newoft->hdr.oft.hdr2len = 0x100-8;

 if (!(newoft->hdr.oft.hdr2 = (char *)calloc(1,newoft->hdr.oft.hdr2len))) { 
   newoft->lock = 0;
   aim_tx_destroy(newoft);
   return -1;
 }

 ft = (struct aim_filetransfer_priv *)conn->priv;

 if(!(aim_oft_buildheader((unsigned char *)newoft->hdr.oft.hdr2, &(ft->fh)))) {
   newoft->lock = 0;
   aim_tx_destroy(newoft);
   return -1;
 }

 newoft->lock = 0;
 aim_tx_enqueue(sess, newoft);
 return 0;
}
 
/*
 * aim_oft_getfile_end - end a getfile.
 * @sess: your session
 * @conn: the getfile connection 
 *
 * call this before you close the getfile connection if you're on the
 * receiving/requesting end.
 */
faim_export int aim_oft_getfile_end(struct aim_session_t *sess, struct aim_conn_t *conn)
{
  struct command_tx_struct *newoft;
  struct aim_filetransfer_priv *ft;
  
  if(!sess || !conn || !conn->priv)
    return -1;

  if(!(newoft = aim_tx_new(AIM_FRAMETYPE_OFT, 0x0204, conn, 0))) {
    faimdprintf(2, "faim: aim_accepttransfer: tx_new OFT failed\n");
    return -1;
  }
  
  newoft->lock = 1;
  
  memcpy(newoft->hdr.oft.magic, "OFT2", 4);
  newoft->hdr.oft.hdr2len = 0x100 - 8;
  
  if (!(newoft->hdr.oft.hdr2 = (char *)calloc(1,newoft->hdr.oft.hdr2len))) {
    newoft->lock = 0;
    aim_tx_destroy(newoft);
    return -1;
  }
  
  ft = (struct aim_filetransfer_priv *)conn->priv;
  ft->state = 4; /* no longer wanting data */
  ft->fh.nrecvd = ft->fh.size;
  ft->fh.recvcsum = ft->fh.checksum;
  ft->fh.flags = 0x21;
  
  if(!(aim_oft_buildheader((unsigned char *)newoft->hdr.oft.hdr2, &(ft->fh)))) {
    newoft->lock = 0;
    aim_tx_destroy(newoft);
    return -1;
  }
  
  newoft->lock = 0;
  aim_tx_enqueue(sess, newoft);
  
  return 0;
}