util_sock.c

samba-3.0.22.tar.gz 编译smb服务器的源码

/* 
   Unix SMB/CIFS implementation.
   Samba utility functions
   Copyright (C) Andrew Tridgell 1992-1998
   Copyright (C) Tim Potter      2000-2001
   Copyright (C) Jeremy Allison  1992-2005
   
   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"

/* the following 3 client_*() functions are nasty ways of allowing
   some generic functions to get info that really should be hidden in
   particular modules */
static int client_fd = -1;
/* What to print out on a client disconnect error. */
static char client_ip_string[16];

void client_setfd(int fd)
{
	client_fd = fd;
	safe_strcpy(client_ip_string, get_peer_addr(client_fd), sizeof(client_ip_string)-1);
}

static char *get_socket_addr(int fd)
{
	struct sockaddr sa;
	struct sockaddr_in *sockin = (struct sockaddr_in *) (&sa);
	socklen_t length = sizeof(sa);
	static fstring addr_buf;

	fstrcpy(addr_buf,"0.0.0.0");

	if (fd == -1) {
		return addr_buf;
	}
	
	if (getsockname(fd, &sa, &length) < 0) {
		DEBUG(0,("getsockname failed. Error was %s\n", strerror(errno) ));
		return addr_buf;
	}
	
	fstrcpy(addr_buf,(char *)inet_ntoa(sockin->sin_addr));
	
	return addr_buf;
}

static int get_socket_port(int fd)
{
	struct sockaddr sa;
	struct sockaddr_in *sockin = (struct sockaddr_in *) (&sa);
	socklen_t length = sizeof(sa);

	if (fd == -1)
		return -1;
	
	if (getsockname(fd, &sa, &length) < 0) {
		DEBUG(0,("getpeername failed. Error was %s\n", strerror(errno) ));
		return -1;
	}
	
	return ntohs(sockin->sin_port);
}

char *client_name(void)
{
	return get_peer_name(client_fd,False);
}

char *client_addr(void)
{
	return get_peer_addr(client_fd);
}

char *client_socket_addr(void)
{
	return get_socket_addr(client_fd);
}

int client_socket_port(void)
{
	return get_socket_port(client_fd);
}

struct in_addr *client_inaddr(struct sockaddr *sa)
{
	struct sockaddr_in *sockin = (struct sockaddr_in *) (sa);
	socklen_t  length = sizeof(*sa);
	
	if (getpeername(client_fd, sa, &length) < 0) {
		DEBUG(0,("getpeername failed. Error was %s\n", strerror(errno) ));
		return NULL;
	}
	
	return &sockin->sin_addr;
}

/* 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;
	socklen_t 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};

typedef struct smb_socket_option {
	const char *name;
	int level;
	int option;
	int value;
	int opttype;
} smb_socket_option;

static const smb_socket_option 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 TCP_KEEPCNT
  {"TCP_KEEPCNT",       IPPROTO_TCP,   TCP_KEEPCNT,     0,                 OPT_INT},
#endif
#ifdef TCP_KEEPIDLE
  {"TCP_KEEPIDLE",      IPPROTO_TCP,   TCP_KEEPIDLE,    0,                 OPT_INT},
#endif
#ifdef TCP_KEEPINTVL
  {"TCP_KEEPINTVL",     IPPROTO_TCP,   TCP_KEEPINTVL,   0,                 OPT_INT},
#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_REUSEPORT
  {"SO_REUSEPORT",      SOL_SOCKET,    SO_REUSEPORT,    0,                 OPT_BOOL},
#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
#ifdef TCP_FASTACK
  {"TCP_FASTACK",       IPPROTO_TCP,   TCP_FASTACK,     0,                 OPT_INT},
#endif
  {NULL,0,0,0,0}};

/****************************************************************************
 Print socket options.
****************************************************************************/

static void print_socket_options(int s)
{
	int value;
	socklen_t vlen = 4;
	const smb_socket_option *p = &socket_options[0];

	/* wrapped in if statement to prevent streams leak in SCO Openserver 5.0 */
	/* reported on samba-technical  --jerry */
	if ( DEBUGLEVEL >= 5 ) {
	for (; p->name != NULL; p++) {
		if (getsockopt(s, p->level, p->option, (void *)&value, &vlen) == -1) {
			DEBUG(5,("Could not test socket option %s.\n", p->name));
		} else {
			DEBUG(5,("socket option %s = %d\n",p->name,value));
			}
		}
	}
 }

/****************************************************************************
 Set user socket options.
****************************************************************************/

void set_socket_options(int fd, const 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_m(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 (Error %s)\n",tok, strerror(errno) ));
	}

	print_socket_options(fd);
}

/****************************************************************************
 Read from a socket.
****************************************************************************/

ssize_t read_udp_socket(int fd,char *buf,size_t len)
{
	ssize_t ret;
	struct sockaddr_in sock;
	socklen_t socklen = sizeof(sock);

	memset((char *)&sock,'\0',socklen);
	memset((char *)&lastip,'\0',sizeof(lastip));
	ret = (ssize_t)sys_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: %lu\n",
			inet_ntoa(lastip), lastport, (unsigned long)ret));

	return(ret);
}

#if 0

Socket routines from HEAD - maybe re-enable in future. JRA.

/****************************************************************************
 Work out if we've timed out.
****************************************************************************/

static BOOL timeout_until(struct timeval *timeout, const struct timeval *endtime)
{
	struct timeval now;
	SMB_BIG_INT t_dif;

	GetTimeOfDay(&now);

	t_dif = usec_time_diff(endtime, &now);
	if (t_dif <= 0) {
		return False;
	}

	timeout->tv_sec = (t_dif / (SMB_BIG_INT)1000000);
	timeout->tv_usec = (t_dif % (SMB_BIG_INT)1000000);
	return True;
}

/****************************************************************************
 Read data from the client, reading exactly N bytes, or until endtime timeout.
 Use with a non-blocking socket if endtime != NULL.
****************************************************************************/

ssize_t read_data_until(int fd,char *buffer,size_t N, const struct timeval *endtime)
{
	ssize_t ret;
	size_t total=0;

	smb_read_error = 0;

	while (total < N) {

		if (endtime != NULL) {
			fd_set r_fds;
			struct timeval timeout;
			int selrtn;

			if (!timeout_until(&timeout, endtime)) {
				DEBUG(10,("read_data_until: read timed out\n"));
				smb_read_error = READ_TIMEOUT;
				return -1;
			}

			FD_ZERO(&r_fds);
			FD_SET(fd, &r_fds);

			/* Select but ignore EINTR. */
			selrtn = sys_select_intr(fd+1, &r_fds, NULL, NULL, &timeout);
			if (selrtn == -1) {
				/* something is wrong. Maybe the socket is dead? */
				DEBUG(0,("read_data_until: select error = %s.\n", strerror(errno) ));
				smb_read_error = READ_ERROR;
				return -1;
			}

			/* Did we timeout ? */
			if (selrtn == 0) {
				DEBUG(10,("read_data_until: select timed out.\n"));
				smb_read_error = READ_TIMEOUT;
				return -1;
			}
		}

		ret = sys_read(fd,buffer + total,N - total);

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

		if (ret == -1) {
			if (errno == EAGAIN) {
				/* Non-blocking socket with no data available. Try select again. */
				continue;
			}
			DEBUG(0,("read_data_until: 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;
}
#endif

/****************************************************************************
 Read data from a socket 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_socket_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) {
			readret = sys_read(fd, buf + nread, maxcnt - nread);
			
			if (readret == 0) {
				DEBUG(5,("read_socket_with_timeout: blocking read. EOF from client.\n"));
				smb_read_error = READ_EOF;
				return -1;
			}
			
			if (readret == -1) {
				if (fd == client_fd) {
					/* Try and give an error message saying what client failed. */
					DEBUG(0,("read_socket_with_timeout: client %s read error = %s.\n",
						client_ip_string, strerror(errno) ));
				} else {
					DEBUG(0,("read_socket_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 */