#include "lfs.h"
#include <glib.h>
#include <stdbool.h>
#include <stdint.h>
#include <sys/socket.h>
#include <sys/types.h>
#include "nbd.h"

Data Structures
struct	SERVER
	Variables associated with a server. More...
struct	CLIENT
	Variables associated with a client connection. More...
struct	FILE_INFO
	Variables associated with an open file. More...
Defines
#define	NBDS_ERR g_quark_from_static_string("server-error-quark")
	Error domain common for all NBD server errors.
#define	msg(prio,...) g_log(G_LOG_DOMAIN, G_LOG_LEVEL_MESSAGE, __VA_ARGS__)
	Logging macros.
#define	MY_NAME "nbd_server"
#define	F_READONLY 1
	Per-export flags:
#define	F_MULTIFILE 2
	flag to tell us a file is exported using -m
#define	F_COPYONWRITE 4
	flag to tell us a file is exported using copyonwrite
#define	F_AUTOREADONLY 8
	flag to tell us a file is set to autoreadonly
#define	F_SPARSE 16
	flag to tell us copyronwrite should use a sparse file
#define	F_SDP 32
	flag to tell us the export should be done using the Socket Direct Protocol for RDMA
#define	F_SYNC 64
	Whether to fsync() after a write.
#define	F_FLUSH 128
	Whether server wants FLUSH to be sent by the client.
#define	F_FUA 256
	Whether server wants FUA to be sent by the client.
#define	F_ROTATIONAL 512
	Whether server wants the client to implement the elevator algorithm.
#define	F_TEMPORARY 1024
	Whether the backing file is temporary and should be created then unlinked.
#define	F_TRIM 2048
	Whether server wants TRIM (discard) to be sent by the client.
#define	F_FIXED 4096
	Client supports fixed new-style protocol (and can thus send us extra options.
#define	F_TREEFILES 8192
	flag to tell us a file is exported using -t
Enumerations
enum	VIRT_STYLE { VIRT_NONE = 0, VIRT_IPLIT, VIRT_IPHASH, VIRT_CIDR }
	Types of virtuatlization. More...
enum	NBDS_ERRS { NBDS_ERR_CFILE_NOTFOUND, NBDS_ERR_CFILE_MISSING_GENERIC, NBDS_ERR_CFILE_KEY_MISSING, NBDS_ERR_CFILE_VALUE_INVALID, NBDS_ERR_CFILE_VALUE_UNSUPPORTED, NBDS_ERR_CFILE_NO_EXPORTS, NBDS_ERR_CFILE_INCORRECT_PORT, NBDS_ERR_CFILE_DIR_UNKNOWN, NBDS_ERR_CFILE_READDIR_ERR, NBDS_ERR_SO_LINGER, NBDS_ERR_SO_REUSEADDR, NBDS_ERR_SO_KEEPALIVE, NBDS_ERR_GAI, NBDS_ERR_SOCKET, NBDS_ERR_BIND, NBDS_ERR_LISTEN, NBDS_ERR_SYS }
	NBD server error codes. More...
Functions
bool	address_matches (const char mask, const struct sockaddr addr, GError **err)
	Check whether a given address matches a given netmask.
uint8_t	getmaskbyte (int masklen) G_GNUC_PURE
	Gets a byte to allow for address masking.
int	authorized_client (CLIENT *opts)
	Check whether a client is allowed to connect.
SERVER *	dup_serve (const SERVER *const s)
	duplicate server
uint64_t	size_autodetect (int fhandle)
	Detect the size of a file.
int	exptrim (struct nbd_request req, CLIENT client)
	Punch a hole in the backend file (if supported by the current system).
void	myseek (int handle, off_t a)
	seek to a position in a file, with error handling.

Define Documentation

#define F_AUTOREADONLY 8

flag to tell us a file is set to autoreadonly

Definition at line 133 of file nbdsrv.h.

Referenced by handle_write(), mainloop(), and setupexport().

#define F_COPYONWRITE 4

flag to tell us a file is exported using copyonwrite

Definition at line 131 of file nbdsrv.h.

Referenced by cmdline(), dump_section(), expflush(), expread(), exptrim(), expwrite(), mainloop(), parse_cfile(), serveconnection(), and setupexport().

#define F_FIXED 4096

Client supports fixed new-style protocol (and can thus send us extra options.

Definition at line 142 of file nbdsrv.h.

#define F_FLUSH 128

Whether server wants FLUSH to be sent by the client.

Definition at line 137 of file nbdsrv.h.

Referenced by parse_cfile(), and send_export_info().

#define F_FUA 256

Whether server wants FUA to be sent by the client.

Definition at line 138 of file nbdsrv.h.

Referenced by parse_cfile(), and send_export_info().

#define F_MULTIFILE 2

flag to tell us a file is exported using -m

Definition at line 130 of file nbdsrv.h.

Referenced by cmdline(), dump_section(), parse_cfile(), and setupexport().

#define F_READONLY 1

Per-export flags:

flag to tell us a file is readonly

Definition at line 129 of file nbdsrv.h.

Referenced by cmdline(), dump_section(), expflush(), exptrim(), get_filepos(), handle_write(), mainloop(), parse_cfile(), send_export_info(), and setupexport().

#define F_ROTATIONAL 512

Whether server wants the client to implement the elevator algorithm.

Definition at line 139 of file nbdsrv.h.

Referenced by parse_cfile(), and send_export_info().

#define F_SDP 32

flag to tell us the export should be done using the Socket Direct Protocol for RDMA

Definition at line 135 of file nbdsrv.h.

Referenced by parse_cfile().

#define F_SPARSE 16

flag to tell us copyronwrite should use a sparse file

Definition at line 134 of file nbdsrv.h.

Referenced by expwrite(), and parse_cfile().

#define F_SYNC 64

Whether to fsync() after a write.

Definition at line 136 of file nbdsrv.h.

Referenced by expwrite(), parse_cfile(), and rawexpwrite().

#define F_TEMPORARY 1024

Whether the backing file is temporary and should be created then unlinked.

Definition at line 140 of file nbdsrv.h.

Referenced by parse_cfile(), and setupexport().

#define F_TREEFILES 8192

flag to tell us a file is exported using -t

Definition at line 143 of file nbdsrv.h.

Referenced by dump_section(), expflush(), exptrim(), get_filepos(), parse_cfile(), rawexpread(), rawexpwrite(), and setupexport().

#define F_TRIM 2048

Whether server wants TRIM (discard) to be sent by the client.

Definition at line 141 of file nbdsrv.h.

Referenced by parse_cfile(), and send_export_info().

#define msg	(	prio,
		...
	)	g_log(G_LOG_DOMAIN, G_LOG_LEVEL_MESSAGE, __VA_ARGS__)

Logging macros.

Todo:: remove this. We should use g_log in all cases, and use the logging mangler to redirect to syslog if and when necessary.

Definition at line 124 of file nbdsrv.h.

Referenced by authorized_client(), copyonwrite_prepare(), handle_modern_connection(), handle_request(), mainloop(), serveloop(), set_peername(), setup_servers(), setupexport(), and spawn_child().

#define MY_NAME "nbd_server"

Definition at line 126 of file nbdsrv.h.

#define NBDS_ERR g_quark_from_static_string("server-error-quark")

Error domain common for all NBD server errors.

Definition at line 88 of file nbdsrv.h.

Referenced by address_matches(), do_cfile_dir(), dosockopts(), main(), open_modern(), open_unix(), and parse_cfile().

Enumeration Type Documentation

enum NBDS_ERRS

NBD server error codes.

Enumerator:

NBDS_ERR_CFILE_NOTFOUND	The configuration file is not found.
NBDS_ERR_CFILE_MISSING_GENERIC	The (required) group "generic" is missing.
NBDS_ERR_CFILE_KEY_MISSING	A (required) key is missing.
NBDS_ERR_CFILE_VALUE_INVALID	A value is syntactically invalid.
NBDS_ERR_CFILE_VALUE_UNSUPPORTED	A value is not supported in this build.
NBDS_ERR_CFILE_NO_EXPORTS	A config file was specified that does not define any exports.
NBDS_ERR_CFILE_INCORRECT_PORT	The reserved port was specified for an old-style export.
NBDS_ERR_CFILE_DIR_UNKNOWN	A directory requested does not exist.
NBDS_ERR_CFILE_READDIR_ERR	Error occurred during readdir()
NBDS_ERR_SO_LINGER	Failed to set SO_LINGER to a socket.
NBDS_ERR_SO_REUSEADDR	Failed to set SO_REUSEADDR to a socket.
NBDS_ERR_SO_KEEPALIVE	Failed to set SO_KEEPALIVE to a socket.
NBDS_ERR_GAI	Failed to get address info.
NBDS_ERR_SOCKET	Failed to create a socket.
NBDS_ERR_BIND	Failed to bind an address to socket.
NBDS_ERR_LISTEN	Failed to start listening on a socket.
NBDS_ERR_SYS	Underlying system call or library error.

Definition at line 93 of file nbdsrv.h.

enum VIRT_STYLE

Types of virtuatlization.

Enumerator:

VIRT_NONE	No virtualization.
VIRT_IPLIT	Literal IP address as part of the filename.
VIRT_IPHASH	Replacing all dots in an ip address by a / before doing the same as in IPLIT.
VIRT_CIDR	Every subnet in its own directory.

Definition at line 19 of file nbdsrv.h.

Function Documentation

bool address_matches	(	const char *	mask,
		const struct sockaddr *	addr,
		GError **	err
	)

Check whether a given address matches a given netmask.

Parameters:

mask	the address or netmask to check against, in ASCII representation
addr	the address to check

Returns:: true if the address matches the mask, false otherwise; in case of failure to parse netmask, returns false with err set appropriately.

Todo:: decide what to do with v6-mapped IPv4 addresses.

Definition at line 29 of file nbdsrv.c.

References getmaskbyte(), NBDS_ERR, and NBDS_ERR_GAI.

Referenced by authorized_client().

int authorized_client ( CLIENT * opts )

Check whether a client is allowed to connect.

Works with an authorization file which contains one line per machine or network, with CIDR-style netmasks.

Parameters:

opts	The client who's trying to connect.

Returns:: 0 - authorization refused, 1 - OK

Definition at line 113 of file nbdsrv.c.

References address_matches(), SERVER::authname, CLIENT::clientaddr, LINELEN, msg, and CLIENT::server.

Referenced by handle_modern_connection().

SERVER* dup_serve ( const SERVER *const s )

duplicate server

Parameters:

s	the old server we want to duplicate

Returns:: new duplicated server

Definition at line 157 of file nbdsrv.c.

References SERVER::authname, SERVER::cidrlen, SERVER::cowdir, SERVER::expected_size, SERVER::exportname, SERVER::flags, SERVER::listenaddr, SERVER::max_connections, SERVER::postrun, SERVER::prerun, SERVER::servename, SERVER::transactionlog, and SERVER::virtstyle.

int exptrim	(	struct nbd_request *	req,
		CLIENT *	client
	)

Punch a hole in the backend file (if supported by the current system).

Parameters:

req	the request for which this is being processed
client	the client for which we're processing this request

Definition at line 240 of file nbdsrv.c.

References DEBUG, delete_treefile(), CLIENT::export, CLIENT::exportname, CLIENT::exportsize, F_COPYONWRITE, F_READONLY, F_TREEFILES, FILE_INFO::fhandle, SERVER::flags, nbd_request::from, nbd_request::len, punch_hole(), CLIENT::server, FILE_INFO::startoff, and TREEPAGESIZE.

Referenced by handle_trim(), and mainloop().

uint8_t getmaskbyte ( int masklen )

Gets a byte to allow for address masking.

Parameters:

masklen the length of the requested mask.

Returns:: if the length of the mask is 8 or longer, 0xFF. Otherwise, a byte with `masklen' number of leading bits set to 1, everything else set to 0.

Definition at line 101 of file nbdsrv.c.

Referenced by address_matches(), and set_peername().

void myseek	(	int	handle,
		off_t	a
	)

seek to a position in a file, with error handling.

Parameters:

handle	a filedescriptor
a	position to seek to

Todo:: get rid of this.

Definition at line 292 of file nbdsrv.c.

References err().

Referenced by expread(), expwrite(), and open_treefile().

uint64_t size_autodetect ( int fhandle )

Detect the size of a file.

Parameters:

fhandle An open filedescriptor

Returns:: the size of the file, or UINT64_MAX if detection was impossible.

Definition at line 199 of file nbdsrv.c.

References __attribute__, and DEBUG.

Referenced by setupexport().

nbdsrv.h File Reference

Data Structures

Defines

Enumerations

Functions

Define Documentation

Enumeration Type Documentation

Function Documentation