process.c

来自「samba-3.0.22.tar.gz 编译smb服务器的源码」· C语言 代码 · 共 1,793 行 · 第 1/4 页

static BOOL receive_message_or_smb(char *buffer, int buffer_len, int timeout)
{
	fd_set fds;
	int selrtn;
	struct timeval to = timeval_set(SMBD_SELECT_TIMEOUT, 0);
	int maxfd;

	smb_read_error = 0;

 again:

	if (timeout >= 0) {
		to.tv_sec = timeout / 1000;
		to.tv_usec = (timeout % 1000) * 1000;
	}

	/*
	 * Note that this call must be before processing any SMB
	 * messages as we need to synchronously process any messages
	 * we may have sent to ourselves from the previous SMB.
	 */
	message_dispatch();

	/*
	 * Check to see if we already have a message on the deferred open queue
	 * and it's time to schedule.
	 */
  	if(deferred_open_queue != NULL) {
		BOOL pop_message = False;
		struct pending_message_list *msg = deferred_open_queue;

		if (timeval_is_zero(&msg->end_time)) {
			pop_message = True;
		} else {
			struct timeval tv;
			SMB_BIG_INT tdif;

			GetTimeOfDay(&tv);
			tdif = usec_time_diff(&msg->end_time, &tv);
			if (tdif <= 0) {
				/* Timed out. Schedule...*/
				pop_message = True;
				DEBUG(10,("receive_message_or_smb: queued message timed out.\n"));
			} else {
				/* Make a more accurate select timeout. */
				to.tv_sec = tdif / 1000000;
				to.tv_usec = tdif % 1000000;
				DEBUG(10,("receive_message_or_smb: select with timeout of [%u.%06u]\n",
					(unsigned int)to.tv_sec, (unsigned int)to.tv_usec ));
			}
		}

		if (pop_message) {
			memcpy(buffer, msg->buf.data, MIN(buffer_len, msg->buf.length));
  
			/* We leave this message on the queue so the open code can
			   know this is a retry. */
			DEBUG(5,("receive_message_or_smb: returning deferred open smb message.\n"));
			return True;
		}
	}

	/*
	 * Setup the select read fd set.
	 */

	FD_ZERO(&fds);

	/*
	 * Ensure we process oplock break messages by preference.
	 * We have to do this before the select, after the select
	 * and if the select returns EINTR. This is due to the fact
	 * that the selects called from async_processing can eat an EINTR
	 * caused by a signal (we can't take the break message there).
	 * This is hideously complex - *MUST* be simplified for 3.0 ! JRA.
	 */

	if (oplock_message_waiting(&fds)) {
		DEBUG(10,("receive_message_or_smb: oplock_message is waiting.\n"));
		async_processing(&fds);
		/*
		 * After async processing we must go and do the select again, as
		 * the state of the flag in fds for the server file descriptor is
		 * indeterminate - we may have done I/O on it in the oplock processing. JRA.
		 */
		goto again;
	}

	{
		struct timeval tmp = timed_events_timeout();
		to = timeval_min(&to, &tmp);
		if (timeval_is_zero(&to)) {
			return True;
		}
	}
	
	FD_SET(smbd_server_fd(),&fds);
	maxfd = setup_oplock_select_set(&fds);

	selrtn = sys_select(MAX(maxfd,smbd_server_fd())+1,&fds,NULL,NULL,&to);

	/* if we get EINTR then maybe we have received an oplock
	   signal - treat this as select returning 1. This is ugly, but
	   is the best we can do until the oplock code knows more about
	   signals */
	if (selrtn == -1 && errno == EINTR) {
		async_processing(&fds);
		/*
		 * After async processing we must go and do the select again, as
		 * the state of the flag in fds for the server file descriptor is
		 * indeterminate - we may have done I/O on it in the oplock processing. JRA.
		 */
		goto again;
	}

	/* Check if error */
	if (selrtn == -1) {
		/* something is wrong. Maybe the socket is dead? */
		smb_read_error = READ_ERROR;
		return False;
	} 
    
	/* Did we timeout ? */
	if (selrtn == 0) {
		smb_read_error = READ_TIMEOUT;
		return False;
	}

	/*
	 * Ensure we process oplock break messages by preference.
	 * This is IMPORTANT ! Otherwise we can starve other processes
	 * sending us an oplock break message. JRA.
	 */

	if (oplock_message_waiting(&fds)) {
		async_processing(&fds);
		/*
		 * After async processing we must go and do the select again, as
		 * the state of the flag in fds for the server file descriptor is
		 * indeterminate - we may have done I/O on it in the oplock processing. JRA.
		 */
		goto again;
	}
	
	return receive_smb(smbd_server_fd(), buffer, 0);
}

/****************************************************************************
Get the next SMB packet, doing the local message processing automatically.
****************************************************************************/

BOOL receive_next_smb(char *inbuf, int bufsize, int timeout)
{
	BOOL got_keepalive;
	BOOL ret;

	do {
		ret = receive_message_or_smb(inbuf,bufsize,timeout);
		
		got_keepalive = (ret && (CVAL(inbuf,0) == SMBkeepalive));
	} while (ret && got_keepalive);

	return ret;
}

/****************************************************************************
 We're terminating and have closed all our files/connections etc.
 If there are any pending local messages we need to respond to them
 before termination so that other smbds don't think we just died whilst
 holding oplocks.
****************************************************************************/

void respond_to_all_remaining_local_messages(void)
{
	/*
	 * Assert we have no exclusive open oplocks.
	 */

	if(get_number_of_exclusive_open_oplocks()) {
		DEBUG(0,("respond_to_all_remaining_local_messages: PANIC : we have %d exclusive oplocks.\n",
			get_number_of_exclusive_open_oplocks() ));
		return;
	}

	process_kernel_oplocks(NULL);

	return;
}


/*
These flags determine some of the permissions required to do an operation 

Note that I don't set NEED_WRITE on some write operations because they
are used by some brain-dead clients when printing, and I don't want to
force write permissions on print services.
*/
#define AS_USER (1<<0)
#define NEED_WRITE (1<<1)
#define TIME_INIT (1<<2)
#define CAN_IPC (1<<3)
#define AS_GUEST (1<<5)
#define DO_CHDIR (1<<6)

/* 
   define a list of possible SMB messages and their corresponding
   functions. Any message that has a NULL function is unimplemented -
   please feel free to contribute implementations!
*/
static const struct smb_message_struct {
	const char *name;
	int (*fn)(connection_struct *conn, char *, char *, int, int);
	int flags;
} smb_messages[256] = {

/* 0x00 */ { "SMBmkdir",reply_mkdir,AS_USER | NEED_WRITE},
/* 0x01 */ { "SMBrmdir",reply_rmdir,AS_USER | NEED_WRITE},
/* 0x02 */ { "SMBopen",reply_open,AS_USER },
/* 0x03 */ { "SMBcreate",reply_mknew,AS_USER},
/* 0x04 */ { "SMBclose",reply_close,AS_USER | CAN_IPC },
/* 0x05 */ { "SMBflush",reply_flush,AS_USER},
/* 0x06 */ { "SMBunlink",reply_unlink,AS_USER | NEED_WRITE }, 
/* 0x07 */ { "SMBmv",reply_mv,AS_USER | NEED_WRITE },
/* 0x08 */ { "SMBgetatr",reply_getatr,AS_USER},
/* 0x09 */ { "SMBsetatr",reply_setatr,AS_USER | NEED_WRITE},
/* 0x0a */ { "SMBread",reply_read,AS_USER},
/* 0x0b */ { "SMBwrite",reply_write,AS_USER | CAN_IPC },
/* 0x0c */ { "SMBlock",reply_lock,AS_USER},
/* 0x0d */ { "SMBunlock",reply_unlock,AS_USER},
/* 0x0e */ { "SMBctemp",reply_ctemp,AS_USER },
/* 0x0f */ { "SMBmknew",reply_mknew,AS_USER}, 
/* 0x10 */ { "SMBchkpth",reply_chkpth,AS_USER},
/* 0x11 */ { "SMBexit",reply_exit,DO_CHDIR},
/* 0x12 */ { "SMBlseek",reply_lseek,AS_USER},
/* 0x13 */ { "SMBlockread",reply_lockread,AS_USER},
/* 0x14 */ { "SMBwriteunlock",reply_writeunlock,AS_USER},
/* 0x15 */ { NULL, NULL, 0 },
/* 0x16 */ { NULL, NULL, 0 },
/* 0x17 */ { NULL, NULL, 0 },
/* 0x18 */ { NULL, NULL, 0 },
/* 0x19 */ { NULL, NULL, 0 },
/* 0x1a */ { "SMBreadbraw",reply_readbraw,AS_USER},
/* 0x1b */ { "SMBreadBmpx",reply_readbmpx,AS_USER},
/* 0x1c */ { "SMBreadBs",NULL,0 },
/* 0x1d */ { "SMBwritebraw",reply_writebraw,AS_USER},
/* 0x1e */ { "SMBwriteBmpx",reply_writebmpx,AS_USER},
/* 0x1f */ { "SMBwriteBs",reply_writebs,AS_USER},
/* 0x20 */ { "SMBwritec",NULL,0},
/* 0x21 */ { NULL, NULL, 0 },
/* 0x22 */ { "SMBsetattrE",reply_setattrE,AS_USER | NEED_WRITE },
/* 0x23 */ { "SMBgetattrE",reply_getattrE,AS_USER },
/* 0x24 */ { "SMBlockingX",reply_lockingX,AS_USER },
/* 0x25 */ { "SMBtrans",reply_trans,AS_USER | CAN_IPC },
/* 0x26 */ { "SMBtranss",NULL,AS_USER | CAN_IPC},
/* 0x27 */ { "SMBioctl",reply_ioctl,0},
/* 0x28 */ { "SMBioctls",NULL,AS_USER},
/* 0x29 */ { "SMBcopy",reply_copy,AS_USER | NEED_WRITE },
/* 0x2a */ { "SMBmove",NULL,AS_USER | NEED_WRITE },
/* 0x2b */ { "SMBecho",reply_echo,0},
/* 0x2c */ { "SMBwriteclose",reply_writeclose,AS_USER},
/* 0x2d */ { "SMBopenX",reply_open_and_X,AS_USER | CAN_IPC },
/* 0x2e */ { "SMBreadX",reply_read_and_X,AS_USER | CAN_IPC },
/* 0x2f */ { "SMBwriteX",reply_write_and_X,AS_USER | CAN_IPC },
/* 0x30 */ { NULL, NULL, 0 },
/* 0x31 */ { NULL, NULL, 0 },
/* 0x32 */ { "SMBtrans2", reply_trans2, AS_USER | CAN_IPC },
/* 0x33 */ { "SMBtranss2", reply_transs2, AS_USER},
/* 0x34 */ { "SMBfindclose", reply_findclose,AS_USER},
/* 0x35 */ { "SMBfindnclose", reply_findnclose, AS_USER},
/* 0x36 */ { NULL, NULL, 0 },
/* 0x37 */ { NULL, NULL, 0 },
/* 0x38 */ { NULL, NULL, 0 },
/* 0x39 */ { NULL, NULL, 0 },
/* 0x3a */ { NULL, NULL, 0 },
/* 0x3b */ { NULL, NULL, 0 },
/* 0x3c */ { NULL, NULL, 0 },
/* 0x3d */ { NULL, NULL, 0 },
/* 0x3e */ { NULL, NULL, 0 },
/* 0x3f */ { NULL, NULL, 0 },
/* 0x40 */ { NULL, NULL, 0 },
/* 0x41 */ { NULL, NULL, 0 },
/* 0x42 */ { NULL, NULL, 0 },
/* 0x43 */ { NULL, NULL, 0 },
/* 0x44 */ { NULL, NULL, 0 },
/* 0x45 */ { NULL, NULL, 0 },
/* 0x46 */ { NULL, NULL, 0 },
/* 0x47 */ { NULL, NULL, 0 },
/* 0x48 */ { NULL, NULL, 0 },
/* 0x49 */ { NULL, NULL, 0 },
/* 0x4a */ { NULL, NULL, 0 },
/* 0x4b */ { NULL, NULL, 0 },
/* 0x4c */ { NULL, NULL, 0 },
/* 0x4d */ { NULL, NULL, 0 },
/* 0x4e */ { NULL, NULL, 0 },
/* 0x4f */ { NULL, NULL, 0 },
/* 0x50 */ { NULL, NULL, 0 },
/* 0x51 */ { NULL, NULL, 0 },
/* 0x52 */ { NULL, NULL, 0 },
/* 0x53 */ { NULL, NULL, 0 },
/* 0x54 */ { NULL, NULL, 0 },
/* 0x55 */ { NULL, NULL, 0 },
/* 0x56 */ { NULL, NULL, 0 },
/* 0x57 */ { NULL, NULL, 0 },
/* 0x58 */ { NULL, NULL, 0 },
/* 0x59 */ { NULL, NULL, 0 },
/* 0x5a */ { NULL, NULL, 0 },
/* 0x5b */ { NULL, NULL, 0 },
/* 0x5c */ { NULL, NULL, 0 },
/* 0x5d */ { NULL, NULL, 0 },
/* 0x5e */ { NULL, NULL, 0 },
/* 0x5f */ { NULL, NULL, 0 },
/* 0x60 */ { NULL, NULL, 0 },
/* 0x61 */ { NULL, NULL, 0 },
/* 0x62 */ { NULL, NULL, 0 },
/* 0x63 */ { NULL, NULL, 0 },
/* 0x64 */ { NULL, NULL, 0 },
/* 0x65 */ { NULL, NULL, 0 },
/* 0x66 */ { NULL, NULL, 0 },
/* 0x67 */ { NULL, NULL, 0 },
/* 0x68 */ { NULL, NULL, 0 },
/* 0x69 */ { NULL, NULL, 0 },
/* 0x6a */ { NULL, NULL, 0 },
/* 0x6b */ { NULL, NULL, 0 },
/* 0x6c */ { NULL, NULL, 0 },
/* 0x6d */ { NULL, NULL, 0 },
/* 0x6e */ { NULL, NULL, 0 },
/* 0x6f */ { NULL, NULL, 0 },
/* 0x70 */ { "SMBtcon",reply_tcon,0},
/* 0x71 */ { "SMBtdis",reply_tdis,DO_CHDIR},
/* 0x72 */ { "SMBnegprot",reply_negprot,0},
/* 0x73 */ { "SMBsesssetupX",reply_sesssetup_and_X,0},
/* 0x74 */ { "SMBulogoffX", reply_ulogoffX, 0}, /* ulogoff doesn't give a valid TID */
/* 0x75 */ { "SMBtconX",reply_tcon_and_X,0},
/* 0x76 */ { NULL, NULL, 0 },
/* 0x77 */ { NULL, NULL, 0 },
/* 0x78 */ { NULL, NULL, 0 },
/* 0x79 */ { NULL, NULL, 0 },
/* 0x7a */ { NULL, NULL, 0 },
/* 0x7b */ { NULL, NULL, 0 },
/* 0x7c */ { NULL, NULL, 0 },
/* 0x7d */ { NULL, NULL, 0 },
/* 0x7e */ { NULL, NULL, 0 },
/* 0x7f */ { NULL, NULL, 0 },
/* 0x80 */ { "SMBdskattr",reply_dskattr,AS_USER},
/* 0x81 */ { "SMBsearch",reply_search,AS_USER},
/* 0x82 */ { "SMBffirst",reply_search,AS_USER},
/* 0x83 */ { "SMBfunique",reply_search,AS_USER},
/* 0x84 */ { "SMBfclose",reply_fclose,AS_USER},
/* 0x85 */ { NULL, NULL, 0 },
/* 0x86 */ { NULL, NULL, 0 },
/* 0x87 */ { NULL, NULL, 0 },
/* 0x88 */ { NULL, NULL, 0 },
/* 0x89 */ { NULL, NULL, 0 },
/* 0x8a */ { NULL, NULL, 0 },
/* 0x8b */ { NULL, NULL, 0 },
/* 0x8c */ { NULL, NULL, 0 },
/* 0x8d */ { NULL, NULL, 0 },
/* 0x8e */ { NULL, NULL, 0 },
/* 0x8f */ { NULL, NULL, 0 },
/* 0x90 */ { NULL, NULL, 0 },
/* 0x91 */ { NULL, NULL, 0 },
/* 0x92 */ { NULL, NULL, 0 },
/* 0x93 */ { NULL, NULL, 0 },
/* 0x94 */ { NULL, NULL, 0 },
/* 0x95 */ { NULL, NULL, 0 },
/* 0x96 */ { NULL, NULL, 0 },
/* 0x97 */ { NULL, NULL, 0 },
/* 0x98 */ { NULL, NULL, 0 },
/* 0x99 */ { NULL, NULL, 0 },
/* 0x9a */ { NULL, NULL, 0 },
/* 0x9b */ { NULL, NULL, 0 },
/* 0x9c */ { NULL, NULL, 0 },
/* 0x9d */ { NULL, NULL, 0 },
/* 0x9e */ { NULL, NULL, 0 },
/* 0x9f */ { NULL, NULL, 0 },
/* 0xa0 */ { "SMBnttrans", reply_nttrans, AS_USER | CAN_IPC },
/* 0xa1 */ { "SMBnttranss", reply_nttranss, AS_USER | CAN_IPC },
/* 0xa2 */ { "SMBntcreateX", reply_ntcreate_and_X, AS_USER | CAN_IPC },
/* 0xa3 */ { NULL, NULL, 0 },
/* 0xa4 */ { "SMBntcancel", reply_ntcancel, 0 },
/* 0xa5 */ { "SMBntrename", reply_ntrename, AS_USER | NEED_WRITE },
/* 0xa6 */ { NULL, NULL, 0 },
/* 0xa7 */ { NULL, NULL, 0 },
/* 0xa8 */ { NULL, NULL, 0 },
/* 0xa9 */ { NULL, NULL, 0 },
/* 0xaa */ { NULL, NULL, 0 },
/* 0xab */ { NULL, NULL, 0 },
/* 0xac */ { NULL, NULL, 0 },
/* 0xad */ { NULL, NULL, 0 },
/* 0xae */ { NULL, NULL, 0 },
/* 0xaf */ { NULL, NULL, 0 },
/* 0xb0 */ { NULL, NULL, 0 },
/* 0xb1 */ { NULL, NULL, 0 },
/* 0xb2 */ { NULL, NULL, 0 },
/* 0xb3 */ { NULL, NULL, 0 },
/* 0xb4 */ { NULL, NULL, 0 },
/* 0xb5 */ { NULL, NULL, 0 },
/* 0xb6 */ { NULL, NULL, 0 },
/* 0xb7 */ { NULL, NULL, 0 },
/* 0xb8 */ { NULL, NULL, 0 },
/* 0xb9 */ { NULL, NULL, 0 },
/* 0xba */ { NULL, NULL, 0 },
/* 0xbb */ { NULL, NULL, 0 },
/* 0xbc */ { NULL, NULL, 0 },
/* 0xbd */ { NULL, NULL, 0 },
/* 0xbe */ { NULL, NULL, 0 },
/* 0xbf */ { NULL, NULL, 0 },
/* 0xc0 */ { "SMBsplopen",reply_printopen,AS_USER},
/* 0xc1 */ { "SMBsplwr",reply_printwrite,AS_USER},
/* 0xc2 */ { "SMBsplclose",reply_printclose,AS_USER},
/* 0xc3 */ { "SMBsplretq",reply_printqueue,AS_USER},
/* 0xc4 */ { NULL, NULL, 0 },
/* 0xc5 */ { NULL, NULL, 0 },
/* 0xc6 */ { NULL, NULL, 0 },
/* 0xc7 */ { NULL, NULL, 0 },
/* 0xc8 */ { NULL, NULL, 0 },
/* 0xc9 */ { NULL, NULL, 0 },
/* 0xca */ { NULL, NULL, 0 },
/* 0xcb */ { NULL, NULL, 0 },
/* 0xcc */ { NULL, NULL, 0 },
/* 0xcd */ { NULL, NULL, 0 },
/* 0xce */ { NULL, NULL, 0 },
/* 0xcf */ { NULL, NULL, 0 },
/* 0xd0 */ { "SMBsends",reply_sends,AS_GUEST},
/* 0xd1 */ { "SMBsendb",NULL,AS_GUEST},
/* 0xd2 */ { "SMBfwdname",NULL,AS_GUEST},
/* 0xd3 */ { "SMBcancelf",NULL,AS_GUEST},
/* 0xd4 */ { "SMBgetmac",NULL,AS_GUEST},
/* 0xd5 */ { "SMBsendstrt",reply_sendstrt,AS_GUEST},
/* 0xd6 */ { "SMBsendend",reply_sendend,AS_GUEST},
/* 0xd7 */ { "SMBsendtxt",reply_sendtxt,AS_GUEST},
/* 0xd8 */ { NULL, NULL, 0 },
/* 0xd9 */ { NULL, NULL, 0 },
/* 0xda */ { NULL, NULL, 0 },
/* 0xdb */ { NULL, NULL, 0 },
/* 0xdc */ { NULL, NULL, 0 },
/* 0xdd */ { NULL, NULL, 0 },
/* 0xde */ { NULL, NULL, 0 },
/* 0xdf */ { NULL, NULL, 0 },
/* 0xe0 */ { NULL, NULL, 0 },
/* 0xe1 */ { NULL, NULL, 0 },
/* 0xe2 */ { NULL, NULL, 0 },
/* 0xe3 */ { NULL, NULL, 0 },
/* 0xe4 */ { NULL, NULL, 0 },
/* 0xe5 */ { NULL, NULL, 0 },
/* 0xe6 */ { NULL, NULL, 0 },
/* 0xe7 */ { NULL, NULL, 0 },
/* 0xe8 */ { NULL, NULL, 0 },