util_sock.c

MC Linux/Unix 终端下文件管理器

/* 
   Unix SMB/Netbios implementation.
   Version 1.9.
   Samba utility functions
   Copyright (C) Andrew Tridgell 1992-1998
   
   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"

#ifdef WITH_SSL
#include <ssl.h>
#undef Realloc  /* SSLeay defines this and samba has a function of this name */
extern SSL  *ssl;
extern int  sslFd;
#endif  /* WITH_SSL */

extern int DEBUGLEVEL;

BOOL passive = False;

/* the client file descriptor */
int Client = -1;

/* the last IP received from */
struct in_addr lastip;

/* the last port received from */
int lastport=0;


int smb_read_error = 0;


/****************************************************************************
determine if a file descriptor is in fact a socket
****************************************************************************/
BOOL is_a_socket(int fd)
{
  int v,l;
  l = sizeof(int);
  return(getsockopt(fd, SOL_SOCKET, SO_TYPE, (char *)&v, &l) == 0);
}


enum SOCK_OPT_TYPES {OPT_BOOL,OPT_INT,OPT_ON};

static const struct
{
  char *name;
  int level;
  int option;
  int value;
  int opttype;
} socket_options[] = {
  {"SO_KEEPALIVE",      SOL_SOCKET,    SO_KEEPALIVE,    0,                 OPT_BOOL},
  {"SO_REUSEADDR",      SOL_SOCKET,    SO_REUSEADDR,    0,                 OPT_BOOL},
  {"SO_BROADCAST",      SOL_SOCKET,    SO_BROADCAST,    0,                 OPT_BOOL},
#ifdef TCP_NODELAY
  {"TCP_NODELAY",       IPPROTO_TCP,   TCP_NODELAY,     0,                 OPT_BOOL},
#endif
#ifdef IPTOS_LOWDELAY
  {"IPTOS_LOWDELAY",    IPPROTO_IP,    IP_TOS,          IPTOS_LOWDELAY,    OPT_ON},
#endif
#ifdef IPTOS_THROUGHPUT
  {"IPTOS_THROUGHPUT",  IPPROTO_IP,    IP_TOS,          IPTOS_THROUGHPUT,  OPT_ON},
#endif
#ifdef SO_SNDBUF
  {"SO_SNDBUF",         SOL_SOCKET,    SO_SNDBUF,       0,                 OPT_INT},
#endif
#ifdef SO_RCVBUF
  {"SO_RCVBUF",         SOL_SOCKET,    SO_RCVBUF,       0,                 OPT_INT},
#endif
#ifdef SO_SNDLOWAT
  {"SO_SNDLOWAT",       SOL_SOCKET,    SO_SNDLOWAT,     0,                 OPT_INT},
#endif
#ifdef SO_RCVLOWAT
  {"SO_RCVLOWAT",       SOL_SOCKET,    SO_RCVLOWAT,     0,                 OPT_INT},
#endif
#ifdef SO_SNDTIMEO
  {"SO_SNDTIMEO",       SOL_SOCKET,    SO_SNDTIMEO,     0,                 OPT_INT},
#endif
#ifdef SO_RCVTIMEO
  {"SO_RCVTIMEO",       SOL_SOCKET,    SO_RCVTIMEO,     0,                 OPT_INT},
#endif
  {NULL,0,0,0,0}};

	

/****************************************************************************
set user socket options
****************************************************************************/
void set_socket_options(int fd, char *options)
{
  fstring tok;

  while (next_token(&options,tok," \t,", sizeof(tok)))
    {
      int ret=0,i;
      int value = 1;
      char *p;
      BOOL got_value = False;

      if ((p = strchr(tok,'=')))
	{
	  *p = 0;
	  value = atoi(p+1);
	  got_value = True;
	}

      for (i=0;socket_options[i].name;i++)
	if (strequal(socket_options[i].name,tok))
	  break;

      if (!socket_options[i].name)
	{
	  DEBUG(0,("Unknown socket option %s\n",tok));
	  continue;
	}

      switch (socket_options[i].opttype)
	{
	case OPT_BOOL:
	case OPT_INT:
	  ret = setsockopt(fd,socket_options[i].level,
			   socket_options[i].option,(char *)&value,sizeof(int));
	  break;

	case OPT_ON:
	  if (got_value)
	    DEBUG(0,("syntax error - %s does not take a value\n",tok));

	  {
	    int on = socket_options[i].value;
	    ret = setsockopt(fd,socket_options[i].level,
			     socket_options[i].option,(char *)&on,sizeof(int));
	  }
	  break;	  
	}
      
      if (ret != 0)
	DEBUG(0,("Failed to set socket option %s\n",tok));
    }
}



/****************************************************************************
  close the socket communication
****************************************************************************/
void close_sockets(void )
{
#ifdef WITH_SSL
  sslutil_disconnect(Client);
#endif /* WITH_SSL */

  close(Client);
  Client = -1;
}



/****************************************************************************
write to a socket
****************************************************************************/
ssize_t write_socket(int fd,char *buf,size_t len)
{
  ssize_t ret=0;

  if (passive)
    return(len);
  DEBUG(6,("write_socket(%d,%d)\n",fd,(int)len));
  ret = write_data(fd,buf,len);
      
  DEBUG(6,("write_socket(%d,%d) wrote %d\n",fd,(int)len,(int)ret));
  if(ret <= 0)
    DEBUG(1,("write_socket: Error writing %d bytes to socket %d: ERRNO = %s\n", 
       (int)len, fd, strerror(errno) ));

  return(ret);
}

/****************************************************************************
read from a socket
****************************************************************************/
ssize_t read_udp_socket(int fd,char *buf,size_t len)
{
  ssize_t ret;
  struct sockaddr_in sock;
  int socklen;
  
  socklen = sizeof(sock);
  memset((char *)&sock,'\0',socklen);
  memset((char *)&lastip,'\0',sizeof(lastip));
  ret = (ssize_t)recvfrom(fd,buf,len,0,(struct sockaddr *)&sock,&socklen);
  if (ret <= 0) {
    DEBUG(2,("read socket failed. ERRNO=%s\n",strerror(errno)));
    return(0);
  }

  lastip = sock.sin_addr;
  lastport = ntohs(sock.sin_port);

  DEBUG(10,("read_udp_socket: lastip %s lastport %d read: %d\n",
             inet_ntoa(lastip), lastport, ret));

  return(ret);
}


/****************************************************************************
read data from a device with a timout in msec.
mincount = if timeout, minimum to read before returning
maxcount = number to be read.
time_out = timeout in milliseconds
****************************************************************************/

ssize_t read_with_timeout(int fd,char *buf,size_t mincnt,size_t maxcnt,unsigned int time_out)
{
  fd_set fds;
  int selrtn;
  ssize_t readret;
  size_t nread = 0;
  struct timeval timeout;

  /* just checking .... */
  if (maxcnt <= 0) return(0);

  smb_read_error = 0;

  /* Blocking read */
  if (time_out <= 0) {
    if (mincnt == 0) mincnt = maxcnt;

    while (nread < mincnt) {
#ifdef WITH_SSL
      if(fd == sslFd){
        readret = SSL_read(ssl, buf + nread, maxcnt - nread);
      }else{
        readret = read(fd, buf + nread, maxcnt - nread);
      }
#else /* WITH_SSL */
      readret = read(fd, buf + nread, maxcnt - nread);
#endif /* WITH_SSL */

      if (readret == 0) {
        DEBUG(5,("read_with_timeout: blocking read. EOF from client.\n"));
        smb_read_error = READ_EOF;
        return -1;
      }

      if (readret == -1) {
        DEBUG(0,("read_with_timeout: read error = %s.\n", strerror(errno) ));
        smb_read_error = READ_ERROR;
        return -1;
      }
      nread += readret;
    }
    return((ssize_t)nread);
  }
  
  /* Most difficult - timeout read */
  /* If this is ever called on a disk file and 
     mincnt is greater then the filesize then
     system performance will suffer severely as 
     select always returns true on disk files */

  /* Set initial timeout */
  timeout.tv_sec = (time_t)(time_out / 1000);
  timeout.tv_usec = (long)(1000 * (time_out % 1000));

  for (nread=0; nread < mincnt; ) 
  {      
    FD_ZERO(&fds);
    FD_SET(fd,&fds);
      
    selrtn = sys_select(fd+1,&fds,&timeout);

    /* Check if error */
    if(selrtn == -1) {
      /* something is wrong. Maybe the socket is dead? */
      DEBUG(0,("read_with_timeout: timeout read. select error = %s.\n", strerror(errno) ));
      smb_read_error = READ_ERROR;
      return -1;
    }

    /* Did we timeout ? */
    if (selrtn == 0) {
      DEBUG(10,("read_with_timeout: timeout read. select timed out.\n"));
      smb_read_error = READ_TIMEOUT;
      return -1;
    }
      
#ifdef WITH_SSL
    if(fd == sslFd){
      readret = SSL_read(ssl, buf + nread, maxcnt - nread);
    }else{
      readret = read(fd, buf + nread, maxcnt - nread);
    }
#else /* WITH_SSL */
    readret = read(fd, buf+nread, maxcnt-nread);
#endif /* WITH_SSL */

    if (readret == 0) {
      /* we got EOF on the file descriptor */
      DEBUG(5,("read_with_timeout: timeout read. EOF from client.\n"));
      smb_read_error = READ_EOF;
      return -1;
    }

    if (readret == -1) {
      /* the descriptor is probably dead */
      DEBUG(0,("read_with_timeout: timeout read. read error = %s.\n", strerror(errno) ));
      smb_read_error = READ_ERROR;
      return -1;
    }
      
    nread += readret;
  }

  /* Return the number we got */
  return((ssize_t)nread);
}


/****************************************************************************
send a keepalive packet (rfc1002)
****************************************************************************/
BOOL send_keepalive(int client)
{
  unsigned char buf[4];

  buf[0] = 0x85;
  buf[1] = buf[2] = buf[3] = 0;

  return(write_data(client,(char *)buf,4) == 4);
}



/****************************************************************************
  read data from the client, reading exactly N bytes. 
****************************************************************************/
ssize_t read_data(int fd,char *buffer,size_t N)
{
  ssize_t  ret;
  size_t total=0;  
 
  smb_read_error = 0;

  while (total < N)
  {
#ifdef WITH_SSL
    if(fd == sslFd){
      ret = SSL_read(ssl, buffer + total, N - total);
    }else{
      ret = read(fd,buffer + total,N - total);
    }
#else /* WITH_SSL */
    ret = read(fd,buffer + total,N - total);
#endif /* WITH_SSL */

    if (ret == 0)
    {
      DEBUG(10,("read_data: read of %d returned 0. Error = %s\n", (int)(N - total), strerror(errno) ));
      smb_read_error = READ_EOF;
      return 0;
    }
    if (ret == -1)
    {
      DEBUG(0,("read_data: read failure for %d. Error = %s\n", (int)(N - total), strerror(errno) ));
      smb_read_error = READ_ERROR;
      return -1;
    }
    total += ret;
  }
  return (ssize_t)total;
}


/****************************************************************************
  write data to a fd 
****************************************************************************/
ssize_t write_data(int fd,char *buffer,size_t N)
{
  size_t total=0;
  ssize_t ret;

  while (total < N)
  {
#ifdef WITH_SSL
    if(fd == sslFd){
      ret = SSL_write(ssl,buffer + total,N - total);
    }else{
      ret = write(fd,buffer + total,N - total);
    }
#else /* WITH_SSL */
    ret = write(fd,buffer + total,N - total);
#endif /* WITH_SSL */

    if (ret == -1) {
      DEBUG(1,("write_data: write failure. Error = %s\n", strerror(errno) ));
      return -1;
    }
    if (ret == 0) return total;

    total += ret;
  }
  return (ssize_t)total;
}



/****************************************************************************
read 4 bytes of a smb packet and return the smb length of the packet
store the result in the buffer
This version of the function will return a length of zero on receiving
a keepalive packet.
timeout is in milliseconds.
****************************************************************************/
static ssize_t read_smb_length_return_keepalive(int fd,char *inbuf,unsigned int timeout)
{
  ssize_t len=0;
  int msg_type;
  BOOL ok = False;

  while (!ok)
  {
    if (timeout > 0)
      ok = (read_with_timeout(fd,inbuf,4,4,timeout) == 4);
    else 
      ok = (read_data(fd,inbuf,4) == 4);

    if (!ok)
      return(-1);