#include "lfs.h"
#include <assert.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/select.h>
#include <sys/wait.h>
#include <sys/ioctl.h>
#include <sys/param.h>
#include <sys/mount.h>
#include <signal.h>
#include <errno.h>
#include <netinet/tcp.h>
#include <netinet/in.h>
#include <netdb.h>
#include <syslog.h>
#include <unistd.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <linux/falloc.h>
#include <arpa/inet.h>
#include <strings.h>
#include <dirent.h>
#include <getopt.h>
#include <pwd.h>
#include <grp.h>
#include <glib.h>
#include "cliserv.h"

Data Structures
struct	SERVER
	Variables associated with a server. More...

struct	FILE_INFO
	Variables associated with a client socket. More...

struct	CLIENT

struct	PARAM
	Configuration file values. More...

Macros
#define	MY_NAME "nbd_server"

#define	SYSCONFDIR "/etc"
	Default position of the config file.

#define	CFILE SYSCONFDIR "/nbd-server/config"

#define	msg2(a, b) g_message((char*)b)
	Logging macros, now nothing goes to syslog unless you say ISSERVER.

#define	msg3(a, b, c) g_message((char*)b,c)

#define	msg4(a, b, c, d) g_message((char*)b,c,d)

#define	DEBUG(...)

#define	OFFT_MAX ~((off_t)1<<(sizeof(off_t)*8-1))
	The highest value a variable of type off_t can reach.

#define	LINELEN 256
	Size of static buffer used to read the authorization file (yuck)

#define	BUFSIZE ((1024*1024)+sizeof(struct nbd_reply))
	Size of buffer that can hold requests.

#define	DIFFPAGESIZE 4096
	diff file uses those chunks

#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_OLDSTYLE 1
	Global flags:

#define	F_LIST 2
	Allow clients to list the exports on a server.

#define	NEG_INIT (1 << 0)

#define	NEG_OLD (1 << 1)

#define	NEG_MODERN (1 << 2)

#define	SEND(net, reply)
	sending macro.

#define	ERROR(client, reply, errcode) { reply.error = htonl(errcode); SEND(client->net,reply); reply.error = 0; }
	error macro.

Enumerations
enum	VIRT_STYLE { VIRT_NONE =0, VIRT_IPLIT, VIRT_IPHASH, VIRT_CIDR }
	Types of virtuatlization. More...

enum	PARAM_TYPE { PARAM_INT, PARAM_INT64, PARAM_STRING, PARAM_BOOL }
	Type of configuration file values. More...

enum	CFILE_ERRORS { CFILE_NOTFOUND, CFILE_MISSING_GENERIC, CFILE_KEY_MISSING, CFILE_VALUE_INVALID, CFILE_VALUE_UNSUPPORTED, CFILE_PROGERR, CFILE_NO_EXPORTS, CFILE_INCORRECT_PORT, CFILE_DIR_UNKNOWN, CFILE_READDIR_ERR }
	Error codes for config file parsing. More...

Functions
static const char *	getcommandname (uint64_t command)
	Translate a command name into human readable form.

int	authorized_client (CLIENT *opts)
	Check whether a client is allowed to connect.

static void	readit (int f, void *buf, size_t len)
	Read data from a file descriptor into a buffer.

static void	consume (int f, void *buf, size_t len, size_t bufsiz)
	Consume data from an FD that we don't want.

static void	writeit (int f, void *buf, size_t len)
	Write data from a buffer into a filedescriptor.

void	usage ()
	Print out a message about how to use nbd-server.

void	dump_section (SERVER serve, gchar section_header)

SERVER *	cmdline (int argc, char *argv[])
	Parse the command line.

void	remove_server (gpointer s)
	Remove a SERVER from memory.

SERVER *	dup_serve (SERVER *s)
	duplicate server

int	append_serve (SERVER s, GArray a)
	append new server to array

GArray *	parse_cfile (gchar f, bool have_global, GError *e)
	Parse the config file.

GArray *	do_cfile_dir (gchar dir, GError *e)
	Parse config file snippets in a directory.

void	sigchld_handler (int s)
	Signal handler for SIGCHLD.

void	killchild (gpointer key, gpointer value, gpointer user_data)
	Kill a child.

void	sigterm_handler (int s)
	Handle SIGTERM and dispatch it to our children.

off_t	size_autodetect (int fhandle)
	Detect the size of a file.

int	get_filepos (GArray export, off_t a, int fhandle, off_t foffset, size_t maxbytes)
	Get the file handle and offset, given an export offset.

void	myseek (int handle, off_t a)
	seek to a position in a file, with error handling.

ssize_t	rawexpwrite (off_t a, char buf, size_t len, CLIENT client, int fua)
	Write an amount of bytes at a given offset to the right file.

int	rawexpwrite_fully (off_t a, char buf, size_t len, CLIENT client, int fua)
	Call rawexpwrite repeatedly until all data has been written.

ssize_t	rawexpread (off_t a, char buf, size_t len, CLIENT client)
	Read an amount of bytes at a given offset from the right file.

int	rawexpread_fully (off_t a, char buf, size_t len, CLIENT client)
	Call rawexpread repeatedly until all data has been read.

int	expread (off_t a, char buf, size_t len, CLIENT client)
	Read an amount of bytes at a given offset from the right file.

int	expwrite (off_t a, char buf, size_t len, CLIENT client, int fua)
	Write an amount of bytes at a given offset to the right file.

int	expflush (CLIENT *client)
	Flush data to a client.

int	exptrim (struct nbd_request req, CLIENT client)

static void	send_reply (uint32_t opt, int net, uint32_t reply_type, size_t datasize, void *data)

static CLIENT *	handle_export_name (uint32_t opt, int net, GArray *servers, uint32_t cflags)

static void	handle_list (uint32_t opt, int net, GArray *servers, uint32_t cflags)

CLIENT *	negotiate (int net, CLIENT client, GArray servers, int phase)
	Do the initial negotiation.

int	mainloop (CLIENT *client)
	Serve a file to a single client.

void	setupexport (CLIENT *client)
	Set up client export array, which is an array of FILE_INFO.

int	copyonwrite_prepare (CLIENT *client)

int	do_run (gchar command, gchar file)
	Run a command.

void	serveconnection (CLIENT *client)
	Serve a connection.

void	set_peername (int net, CLIENT *client)
	Find the name of the file we have to serve.

void	destroy_pid_t (gpointer data)
	Destroy a pid_t*.

int	serveloop (GArray *servers)
	Loop through the available servers, and serve them.

void	dosockopts (int socket)

int	setup_serve (SERVER *serve)
	Connect a server's socket.

void	open_modern (void)

void	setup_servers (GArray *servers)
	Connect our servers.

void	daemonize (SERVER *serve)
	Go daemon (unless we specified at compile time that we didn't want this)

void	serve_err (SERVER serve, const char msg) G_GNUC_NORETURN

void	dousers (void)
	Set up user-ID and/or group-ID.

void	glib_message_syslog_redirect (const gchar log_domain, GLogLevelFlags log_level, const gchar message, gpointer user_data)

int	main (int argc, char *argv[])
	Main entry point...

Variables
gchar *	config_file_pos
	Where our config file actually is.

gchar *	runuser =NULL
	What user we're running as.

gchar *	rungroup =NULL
	What group we're running as.

int	glob_flags =0
	global flags

int	dontfork = 0

GHashTable *	children

char	pidfname [256]
	name of our PID file

char	pidftemplate [256]
	template to be used for the filename of the PID file

char	default_authname [] = SYSCONFDIR "/nbd-server/allow"
	default name of allow file

int	modernsock =0
	Socket for the modern handler.

char *	modern_listen
	listenaddr value for modernsock

char *	modernport =NBD_DEFAULT_PORT
	Port number on which to listen for new-style nbd-client connections.

bool	logged_oversized =false
	whether we logged oversized requests already

Macro Definition Documentation

#define BUFSIZE ((1024*1024)+sizeof(struct nbd_reply))

Size of buffer that can hold requests.

Definition at line 156 of file nbd-server.c.

Referenced by mainloop().

#define CFILE SYSCONFDIR "/nbd-server/config"

Definition at line 113 of file nbd-server.c.

Referenced by main(), and usage().

#define DEBUG ( ... )

Definition at line 144 of file nbd-server.c.

Referenced by expread(), exptrim(), expwrite(), mainloop(), rawexpread(), rawexpwrite(), readit(), serveloop(), setup_serve(), setupexport(), sigchld_handler(), size_autodetect(), and writeit().

#define DIFFPAGESIZE 4096

diff file uses those chunks

Definition at line 157 of file nbd-server.c.

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

#define ERROR	(	client,
		reply,
		errcode
	)	{ reply.error = htonl(errcode); SEND(client->net,reply); reply.error = 0; }

error macro.

Definition at line 1704 of file nbd-server.c.

Referenced by mainloop().

#define F_AUTOREADONLY 8

flag to tell us a file is set to autoreadonly

Definition at line 164 of file nbd-server.c.

Referenced by mainloop(), and setupexport().

#define F_COPYONWRITE 4

flag to tell us a file is exported using copyonwrite

Definition at line 162 of file nbd-server.c.

Referenced by cmdline(), dump_section(), expflush(), expread(), 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 173 of file nbd-server.c.

#define F_FLUSH 128

Whether server wants FLUSH to be sent by the client.

Definition at line 168 of file nbd-server.c.

Referenced by negotiate(), and parse_cfile().

#define F_FUA 256

Whether server wants FUA to be sent by the client.

Definition at line 169 of file nbd-server.c.

Referenced by negotiate(), and parse_cfile().

#define F_LIST 2

Allow clients to list the exports on a server.

Definition at line 177 of file nbd-server.c.

Referenced by handle_list(), and parse_cfile().

#define F_MULTIFILE 2

flag to tell us a file is exported using -m

Definition at line 161 of file nbd-server.c.

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

#define F_OLDSTYLE 1

Global flags:

Allow oldstyle (port-based) exports

Definition at line 176 of file nbd-server.c.

Referenced by cmdline(), parse_cfile(), and setup_serve().

#define F_READONLY 1

Per-export flags:

flag to tell us a file is readonly

Definition at line 160 of file nbd-server.c.

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

#define F_ROTATIONAL 512

Whether server wants the client to implement the elevator algorithm.

Definition at line 170 of file nbd-server.c.

Referenced by negotiate(), and parse_cfile().

#define F_SDP 32

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

Definition at line 166 of file nbd-server.c.

Referenced by parse_cfile(), and setup_serve().

#define F_SPARSE 16

flag to tell us copyronwrite should use a sparse file

Definition at line 165 of file nbd-server.c.

Referenced by expwrite(), and parse_cfile().

#define F_SYNC 64

Whether to fsync() after a write.

Definition at line 167 of file nbd-server.c.

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 171 of file nbd-server.c.

Referenced by parse_cfile(), and setupexport().

#define F_TRIM 2048

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

Definition at line 172 of file nbd-server.c.

Referenced by negotiate(), and parse_cfile().

#define LINELEN 256

Size of static buffer used to read the authorization file (yuck)

Definition at line 154 of file nbd-server.c.

Referenced by authorized_client().

#define msg2	(	a,
		b
	)	g_message((char*)b)

Logging macros, now nothing goes to syslog unless you say ISSERVER.

Definition at line 134 of file nbd-server.c.

Referenced by mainloop(), and serveloop().

#define msg3	(	a,
		b,
		c
	)	g_message((char*)b,c)

Definition at line 135 of file nbd-server.c.

Referenced by copyonwrite_prepare(), serveloop(), set_peername(), setupexport(), and sigchld_handler().

#define msg4	(	a,
		b,
		c,
		d
	)	g_message((char*)b,c,d)

Definition at line 136 of file nbd-server.c.

Referenced by authorized_client(), and set_peername().

#define MY_NAME "nbd_server"

Definition at line 102 of file nbd-server.c.

#define NEG_INIT (1 << 0)

Definition at line 183 of file nbd-server.c.

Referenced by mainloop(), negotiate(), and serveloop().

#define NEG_MODERN (1 << 2)

Definition at line 185 of file nbd-server.c.

Referenced by mainloop(), negotiate(), and serveloop().

#define NEG_OLD (1 << 1)

Definition at line 184 of file nbd-server.c.

Referenced by mainloop(), and negotiate().

#define OFFT_MAX ~((off_t)1<<(sizeof(off_t)*8-1))

The highest value a variable of type off_t can reach.

This is a signed integer, so set all bits except for the leftmost one.

Definition at line 153 of file nbd-server.c.

Referenced by handle_export_name(), main(), mainloop(), serveloop(), and size_autodetect().

#define SEND	(	net,
		reply
	)

Value:

{ writeit( net, &reply, sizeof( reply )); \
        if (client->transactionlogfd != -1) \
                writeit(client->transactionlogfd, &reply, sizeof(reply)); }

sending macro.

Definition at line 1700 of file nbd-server.c.

Referenced by mainloop().

#define SYSCONFDIR "/etc"

Default position of the config file.

Definition at line 111 of file nbd-server.c.

Enumeration Type Documentation

enum CFILE_ERRORS

Error codes for config file parsing.

Enumerator:

CFILE_NOTFOUND	The configuration file is not found.
CFILE_MISSING_GENERIC	The (required) group "generic" is missing.
CFILE_KEY_MISSING	A (required) key is missing.
CFILE_VALUE_INVALID	A value is syntactically invalid.
CFILE_VALUE_UNSUPPORTED	A value is not supported in this build.
CFILE_PROGERR	Programmer error.
CFILE_NO_EXPORTS	A config file was specified that does not define any exports.
CFILE_INCORRECT_PORT	The reserved port was specified for an old-style export.
CFILE_DIR_UNKNOWN	A directory requested does not exist.
CFILE_READDIR_ERR	Error occurred during readdir()

Definition at line 615 of file nbd-server.c.

enum PARAM_TYPE

Type of configuration file values.

Enumerator:

PARAM_INT	This parameter is an integer.
PARAM_INT64	This parameter is an integer.
PARAM_STRING	This parameter is a string.
PARAM_BOOL	This parameter is a boolean.

Definition at line 265 of file nbd-server.c.

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 201 of file nbd-server.c.

Function Documentation

int append_serve	(	SERVER *	s,
		GArray *	a
	)

append new server to array

Parameters

s	server
a	server array

Returns: 0 success, -1 error

Definition at line 705 of file nbd-server.c.

References dup_serve(), err(), SERVER::listenaddr, SERVER::port, and SERVER::socket_family.

Referenced by main(), and parse_cfile().

int authorized_client ( CLIENT * opts )

Check whether a client is allowed to connect.

Works with an authorization file which contains one line per machine, no wildcards.

Parameters

opts	The client who's trying to connect.

Returns: 0 - authorization refused, 1 - OK

Definition at line 318 of file nbd-server.c.

References SERVER::authname, CLIENT::clientname, len, LINELEN, msg4, and CLIENT::server.

Referenced by serveloop().

SERVER* cmdline	(	int	argc,
		char *	argv[]
	)

Parse the command line.

Parameters

argc	the argc argument to main()
argv	the argv argument to main()

Definition at line 475 of file nbd-server.c.

References SERVER::authname, config_file_pos, default_authname, dontfork, dump_section(), SERVER::expected_size, SERVER::exportname, F_COPYONWRITE, F_MULTIFILE, F_OLDSTYLE, F_READONLY, SERVER::flags, glob_flags, SERVER::listenaddr, SERVER::max_connections, pidftemplate, SERVER::port, usage(), VIRT_IPLIT, and SERVER::virtstyle.

Referenced by main().

static void consume	(	int	f,
		void *	buf,
		size_t	len,
		size_t	bufsiz
	)

inlinestatic

Consume data from an FD that we don't want.

Parameters

f	a file descriptor
buf	a buffer
len	the number of bytes to consume
bufsiz	the size of the buffer

Definition at line 395 of file nbd-server.c.

References readit().

Referenced by mainloop().

int copyonwrite_prepare ( CLIENT * client )

Definition at line 1979 of file nbd-server.c.

References CLIENT::clientname, CLIENT::difffile, CLIENT::difffilename, DIFFPAGESIZE, CLIENT::difmap, err(), CLIENT::exportname, CLIENT::exportsize, and msg3.

Referenced by serveconnection().

void daemonize ( SERVER * serve )

Go daemon (unless we specified at compile time that we didn't want this)

Parameters

serve the first server of our configuration. If its port is zero, then do not daemonize, because we're doing inetd then. This parameter is only used to create a PID file of the form /var/run/nbd-server.<port>.pid; it's not modified in any way.

Definition at line 2452 of file nbd-server.c.

References err(), pidfname, pidftemplate, and SERVER::port.

Referenced by main().

void destroy_pid_t ( gpointer data )

Destroy a pid_t*.

Parameters

data	a pointer to pid_t which should be freed

Definition at line 2156 of file nbd-server.c.

Referenced by setup_servers().

GArray* do_cfile_dir	(	gchar *	dir,
		GError **	e
	)

Parse config file snippets in a directory.

Uses readdir() and friends to find files and open them, then passes them on to parse_cfile with have_global set false

Definition at line 773 of file nbd-server.c.

References CFILE_DIR_UNKNOWN, CFILE_READDIR_ERR, and parse_cfile().

Referenced by parse_cfile().

int do_run	(	gchar *	command,
		gchar *	file
	)

Run a command.

This is used for the prerun'' andpostrun'' config file options

Parameters

command	the command to be ran. Read from the config file
file	the file name we're about to export

Definition at line 2003 of file nbd-server.c.

Referenced by serveconnection().

void dosockopts ( int socket )

Definition at line 2285 of file nbd-server.c.

References err().

Referenced by open_modern(), and setup_serve().

void dousers ( void )

Set up user-ID and/or group-ID.

Definition at line 2498 of file nbd-server.c.

References err(), rungroup, and runuser.

Referenced by main().

void dump_section	(	SERVER *	serve,
		gchar *	section_header
	)

Definition at line 446 of file nbd-server.c.

References SERVER::authname, SERVER::expected_size, SERVER::exportname, F_COPYONWRITE, F_MULTIFILE, F_READONLY, SERVER::flags, SERVER::listenaddr, and SERVER::port.

Referenced by cmdline().

SERVER* dup_serve ( SERVER * s )

duplicate server

Parameters

s	the old server we want to duplicate

Returns: new duplicated server

Definition at line 656 of file nbd-server.c.

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

Referenced by append_serve().

int expflush ( CLIENT * client )

Flush data to a client.

Parameters

client The client we're going to write for.

Returns: 0 on success, nonzero on failure

Definition at line 1466 of file nbd-server.c.

References CLIENT::difffile, CLIENT::export, F_COPYONWRITE, FILE_INFO::fhandle, SERVER::flags, and CLIENT::server.

Referenced by mainloop().

int expread	(	off_t	a,
		char *	buf,
		size_t	len,
		CLIENT *	client
	)

Read an amount of bytes at a given offset from the right file.

This abstracts the read-side of the copyonwrite stuff, and calls rawexpread() with the right parameters to do the actual work.

Parameters

a	The offset where the read should start
buf	A buffer to read into
len	The size of buf
client	The client we're going to read for

Returns: 0 on success, nonzero on failure

Definition at line 1366 of file nbd-server.c.

References DEBUG, CLIENT::difffile, DIFFPAGESIZE, CLIENT::difmap, F_COPYONWRITE, SERVER::flags, myseek(), rawexpread_fully(), and CLIENT::server.

Referenced by mainloop().

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

Definition at line 1486 of file nbd-server.c.

References DEBUG, CLIENT::export, FILE_INFO::fhandle, nbd_request::from, nbd_request::len, and FILE_INFO::startoff.

Referenced by mainloop().

int expwrite	(	off_t	a,
		char *	buf,
		size_t	len,
		CLIENT *	client,
		int	fua
	)

Write an amount of bytes at a given offset to the right file.

This abstracts the write-side of the copyonwrite option, and calls rawexpwrite() with the right parameters to do the actual work.

Parameters

a	The offset where the write should start
buf	The buffer to write from
len	The length of buf
client	The client we're going to write for.
fua	Flag to indicate 'Force Unit Access'

Returns: 0 on success, nonzero on failure

Definition at line 1408 of file nbd-server.c.

References DEBUG, CLIENT::difffile, CLIENT::difffilelen, DIFFPAGESIZE, CLIENT::difmap, F_COPYONWRITE, F_SPARSE, F_SYNC, fdatasync, SERVER::flags, myseek(), rawexpread_fully(), rawexpwrite_fully(), and CLIENT::server.

Referenced by mainloop().

int get_filepos	(	GArray *	export,
		off_t	a,
		int *	fhandle,
		off_t *	foffset,
		size_t *	maxbytes
	)

Get the file handle and offset, given an export offset.

Parameters

export	An array of export files
a	The offset to get corresponding file/offset for
fhandle	[out] File descriptor
foffset	[out] Offset into fhandle
maxbytes	[out] Tells how many bytes can be read/written from fhandle starting at foffset (0 if there is no limit)

Returns: 0 on success, -1 on failure

Definition at line 1171 of file nbd-server.c.

References FILE_INFO::fhandle, and FILE_INFO::startoff.

Referenced by rawexpread(), and rawexpwrite().

static const char* getcommandname ( uint64_t command )

inlinestatic

Translate a command name into human readable form.

Parameters

command The command number (after applying NBD_CMD_MASK_COMMAND)

Returns: pointer to the command name

Definition at line 295 of file nbd-server.c.

References NBD_CMD_DISC, NBD_CMD_FLUSH, NBD_CMD_READ, and NBD_CMD_WRITE.

Referenced by mainloop().

void glib_message_syslog_redirect	(	const gchar *	log_domain,
		GLogLevelFlags	log_level,
		const gchar *	message,
		gpointer	user_data
	)

Definition at line 2525 of file nbd-server.c.

Referenced by main().

static CLIENT* handle_export_name	(	uint32_t	opt,
		int	net,
		GArray *	servers,
		uint32_t	cflags
	)

static

Definition at line 1525 of file nbd-server.c.

References CLIENT::clientfeats, err(), CLIENT::exportsize, CLIENT::modern, CLIENT::net, OFFT_MAX, SERVER::servename, CLIENT::server, and CLIENT::transactionlogfd.

Referenced by negotiate().

static void handle_list	(	uint32_t	opt,
		int	net,
		GArray *	servers,
		uint32_t	cflags
	)

static

Definition at line 1555 of file nbd-server.c.

References err(), err_nonfatal(), F_LIST, glob_flags, len, NBD_REP_ACK, NBD_REP_ERR_INVALID, NBD_REP_ERR_POLICY, NBD_REP_SERVER, send_reply(), and SERVER::servename.

Referenced by negotiate().

void killchild	(	gpointer	key,
		gpointer	value,
		gpointer	user_data
	)

Kill a child.

Called from sigterm_handler::g_hash_table_foreach.

Parameters

key	the key
value	the value corresponding to the above key
user_data	a pointer which we always set to 1, so that we know what will happen next.

Definition at line 1087 of file nbd-server.c.

Referenced by sigterm_handler().

int main	(	int	argc,
		char *	argv[]
	)

Main entry point...

Definition at line 2559 of file nbd-server.c.

References append_serve(), CFILE, CFILE_NOTFOUND, cmdline(), config_file_pos, daemonize(), dontfork, dousers(), err(), CLIENT::exportsize, glib_message_syslog_redirect(), logging(), CLIENT::net, OFFT_MAX, parse_cfile(), pidftemplate, SERVER::port, serveconnection(), serveloop(), CLIENT::server, set_peername(), setup_servers(), and SERVER::socket_family.

int mainloop ( CLIENT * client )

Serve a file to a single client.

Todo:: This beast needs to be split up in many tiny little manageable pieces. Preferably with a chainsaw.

Parameters

client The client we're going to serve to.

Returns: when the client disconnects

Definition at line 1714 of file nbd-server.c.

References BUFSIZE, consume(), DEBUG, CLIENT::difffile, CLIENT::difffilename, CLIENT::difmap, err(), nbd_reply::error, ERROR, expflush(), CLIENT::exportsize, expread(), exptrim(), expwrite(), F_AUTOREADONLY, F_COPYONWRITE, F_READONLY, SERVER::flags, nbd_request::from, getcommandname(), nbd_request::handle, nbd_reply::handle, nbd_request::len, len, logged_oversized, nbd_request::magic, nbd_reply::magic, CLIENT::modern, msg2, NBD_CMD_DISC, NBD_CMD_FLAG_FUA, NBD_CMD_FLUSH, NBD_CMD_MASK_COMMAND, NBD_CMD_READ, NBD_CMD_TRIM, NBD_CMD_WRITE, NBD_REPLY_MAGIC, NBD_REQUEST_MAGIC, NEG_INIT, NEG_MODERN, NEG_OLD, negotiate(), CLIENT::net, ntohll(), OFFT_MAX, readit(), SEND, CLIENT::server, CLIENT::transactionlogfd, nbd_request::type, and writeit().

Referenced by serveconnection().

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; lastpoint is a global variable right now, but it shouldn't be. If we pass it on as a parameter, that makes things a lot easier.

Definition at line 1216 of file nbd-server.c.

References err().

Referenced by expread(), expwrite(), rawexpread(), and rawexpwrite().

CLIENT* negotiate	(	int	net,
		CLIENT *	client,
		GArray *	servers,
		int	phase
	)

Do the initial negotiation.

Parameters

client The client we're negotiating with.

Definition at line 1587 of file nbd-server.c.

References cliserv_magic, err(), err_nonfatal(), CLIENT::exportsize, F_FLUSH, F_FUA, F_READONLY, F_ROTATIONAL, F_TRIM, SERVER::flags, handle_export_name(), handle_list(), htonll, INIT_PASSWD, magic, NBD_FLAG_FIXED_NEWSTYLE, NBD_FLAG_HAS_FLAGS, NBD_FLAG_READ_ONLY, NBD_FLAG_ROTATIONAL, NBD_FLAG_SEND_FLUSH, NBD_FLAG_SEND_FUA, NBD_FLAG_SEND_TRIM, NBD_OPT_ABORT, NBD_OPT_EXPORT_NAME, NBD_OPT_LIST, NBD_REP_ERR_UNSUP, NEG_INIT, NEG_MODERN, NEG_OLD, CLIENT::net, ntohll(), opts_magic, send_reply(), and CLIENT::server.

void open_modern ( void )

Definition at line 2384 of file nbd-server.c.

References dosockopts(), err(), modern_listen, modernport, and modernsock.

Referenced by setup_servers().

GArray * parse_cfile	(	gchar *	f,
		bool	have_global,
		GError **	e
	)

Parse the config file.

Parameters

f	the name of the config file
e	a GError.

See Also: CFILE_ERRORS for what error values this function can return.

Returns: a Array of SERVER* pointers, If the config file is empty or does not exist, returns an empty GHashTable; if the config file contains an error, returns NULL, and e is set appropriately

Definition at line 842 of file nbd-server.c.

References append_serve(), SERVER::authname, CFILE_MISSING_GENERIC, CFILE_NO_EXPORTS, CFILE_NOTFOUND, CFILE_VALUE_INVALID, CFILE_VALUE_UNSUPPORTED, SERVER::cidrlen, do_cfile_dir(), err(), SERVER::expected_size, SERVER::exportname, F_COPYONWRITE, F_FLUSH, F_FUA, F_LIST, F_MULTIFILE, F_OLDSTYLE, F_READONLY, F_ROTATIONAL, F_SDP, F_SPARSE, F_SYNC, F_TEMPORARY, F_TRIM, SERVER::flags, PARAM::flagval, glob_flags, SERVER::listenaddr, SERVER::max_connections, modern_listen, modernport, PARAM_BOOL, PARAM_INT, PARAM_INT64, PARAM_OFFT, PARAM_STRING, SERVER::port, SERVER::postrun, SERVER::prerun, PARAM::required, rungroup, runuser, SERVER::servename, SERVER::socket_family, SERVER::transactionlog, VIRT_CIDR, VIRT_IPHASH, VIRT_IPLIT, VIRT_NONE, and SERVER::virtstyle.

Referenced by do_cfile_dir(), and main().

ssize_t rawexpread	(	off_t	a,
		char *	buf,
		size_t	len,
		CLIENT *	client
	)

Read an amount of bytes at a given offset from the right file.

This abstracts the read-side of the multiple files option.

Parameters

a	The offset where the read should start
buf	A buffer to read into
len	The size of buf
client	The client we're serving for

Returns: The number of bytes actually read, or -1 in case of an error.

Definition at line 1325 of file nbd-server.c.

References DEBUG, CLIENT::export, get_filepos(), and myseek().

Referenced by rawexpread_fully().

int rawexpread_fully	(	off_t	a,
		char *	buf,
		size_t	len,
		CLIENT *	client
	)

Call rawexpread repeatedly until all data has been read.

Returns: 0 on success, nonzero on failure

Definition at line 1345 of file nbd-server.c.

References rawexpread().

Referenced by expread(), and expwrite().

ssize_t rawexpwrite	(	off_t	a,
		char *	buf,
		size_t	len,
		CLIENT *	client,
		int	fua
	)

Write an amount of bytes at a given offset to the right file.

This abstracts the write-side of the multiple file option.

Parameters

a	The offset where the write should start
buf	The buffer to write from
len	The length of buf
client	The client we're serving for
fua	Flag to indicate 'Force Unit Access'

Returns: The number of bytes actually written, or -1 in case of an error

Definition at line 1233 of file nbd-server.c.

References DEBUG, CLIENT::export, F_SYNC, fdatasync, SERVER::flags, get_filepos(), myseek(), and CLIENT::server.

Referenced by rawexpwrite_fully().

int rawexpwrite_fully	(	off_t	a,
		char *	buf,
		size_t	len,
		CLIENT *	client,
		int	fua
	)

Call rawexpwrite repeatedly until all data has been written.

Parameters

a	The offset where the write should start
buf	The buffer to write from
len	The length of buf
client	The client we're serving for
fua	Flag to indicate 'Force Unit Access'

Returns: 0 on success, nonzero on failure

Definition at line 1303 of file nbd-server.c.

References rawexpwrite().

Referenced by expwrite().

static void readit	(	int	f,
		void *	buf,
		size_t	len
	)

inlinestatic

Read data from a file descriptor into a buffer.

Parameters

f	a file descriptor
buf	a buffer
len	the number of bytes to be read

Definition at line 372 of file nbd-server.c.

References DEBUG, and err().

Referenced by consume(), and mainloop().

void remove_server ( gpointer s )

Remove a SERVER from memory.

Used from the hash table

Definition at line 633 of file nbd-server.c.

References SERVER::authname, SERVER::exportname, SERVER::listenaddr, SERVER::postrun, SERVER::prerun, and SERVER::transactionlog.

static void send_reply	(	uint32_t	opt,
		int	net,
		uint32_t	reply_type,
		size_t	datasize,
		void *	data
	)

static

Definition at line 1511 of file nbd-server.c.

References htonll, and magic.

Referenced by handle_list(), and negotiate().

void serve_err	(	SERVER *	serve,
		const char *	msg
	)

Definition at line 2489 of file nbd-server.c.

References err(), SERVER::exportname, and SERVER::port.

void serveconnection ( CLIENT * client )

Serve a connection.

Todo:: allow for multithreading, perhaps use libevent. Not just yet, though; follow the road map.

Parameters

client a connected client

Definition at line 2023 of file nbd-server.c.

References copyonwrite_prepare(), do_run(), CLIENT::exportname, F_COPYONWRITE, SERVER::flags, mainloop(), CLIENT::net, SERVER::postrun, SERVER::prerun, CLIENT::server, setmysockopt(), setupexport(), SERVER::transactionlog, and CLIENT::transactionlogfd.

Referenced by main(), and serveloop().

int serveloop ( GArray * servers )

Loop through the available servers, and serve them.

Never returns.

Definition at line 2163 of file nbd-server.c.

References authorized_client(), children, DEBUG, dontfork, err(), err_nonfatal(), CLIENT::exportsize, SERVER::max_connections, modernsock, msg2, msg3, NEG_INIT, NEG_MODERN, negotiate(), CLIENT::net, OFFT_MAX, serveconnection(), CLIENT::server, set_peername(), SERVER::socket, and CLIENT::transactionlogfd.

Referenced by main().

void set_peername	(	int	net,
		CLIENT *	client
	)

Find the name of the file we have to serve.

This will use g_strdup_printf to put the IP address of the client inside a filename containing "%s" (in the form as specified by the "virtstyle" option). That name is then written to client->exportname.

Parameters

net	A socket connected to an nbd client
client	information about the client. The IP address in human-readable format will be written to a new char* buffer, the address of which will be stored in client->clientname.

Definition at line 2065 of file nbd-server.c.

References SERVER::cidrlen, CLIENT::clientname, err(), SERVER::exportname, CLIENT::exportname, msg3, msg4, CLIENT::server, VIRT_CIDR, VIRT_IPHASH, VIRT_IPLIT, VIRT_NONE, and SERVER::virtstyle.

Referenced by main(), and serveloop().

int setup_serve ( SERVER * serve )

Connect a server's socket.

Parameters

serve the server we want to connect.

Definition at line 2323 of file nbd-server.c.

References DEBUG, dosockopts(), err(), F_OLDSTYLE, F_SDP, SERVER::flags, glob_flags, SERVER::listenaddr, SERVER::port, SERVER::servename, SERVER::socket, and SERVER::socket_family.

Referenced by setup_servers().

void setup_servers ( GArray * servers )

Connect our servers.

Definition at line 2419 of file nbd-server.c.

References children, destroy_pid_t(), err(), open_modern(), setup_serve(), sigchld_handler(), and sigterm_handler().

Referenced by main().

void setupexport ( CLIENT * client )

Set up client export array, which is an array of FILE_INFO.

Also, split a single exportfile into multiple ones, if that was asked.

Parameters

client information on the client which we want to setup export for

Definition at line 1877 of file nbd-server.c.

References DEBUG, err(), SERVER::expected_size, CLIENT::export, CLIENT::exportname, CLIENT::exportsize, F_AUTOREADONLY, F_COPYONWRITE, F_MULTIFILE, F_READONLY, F_TEMPORARY, FILE_INFO::fhandle, SERVER::flags, msg3, CLIENT::server, size_autodetect(), and FILE_INFO::startoff.

Referenced by serveconnection().

void sigchld_handler ( int s )

Signal handler for SIGCHLD.

Parameters

s	the signal we're handling (must be SIGCHLD, or something is severely wrong)

Definition at line 1060 of file nbd-server.c.

References children, DEBUG, and msg3.

Referenced by setup_servers().

void sigterm_handler ( int s )

Handle SIGTERM and dispatch it to our children.

Parameters

s	the signal we're handling (must be SIGTERM, or something is severely wrong).

Definition at line 1100 of file nbd-server.c.

References children, killchild(), and pidfname.

Referenced by setup_servers().

off_t size_autodetect ( int fhandle )

Detect the size of a file.

Parameters

fhandle An open filedescriptor

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

Definition at line 1119 of file nbd-server.c.

References __attribute__, DEBUG, err(), and OFFT_MAX.

Referenced by setupexport().

void usage ( )

Print out a message about how to use nbd-server.

Split out to a separate function so that we can call it from multiple places

Definition at line 427 of file nbd-server.c.

References CFILE, and VERSION.

static void writeit	(	int	f,
		void *	buf,
		size_t	len
	)

inlinestatic

Write data from a buffer into a filedescriptor.

Parameters

f	a file descriptor
buf	a buffer containing data
len	the number of bytes to be written

Definition at line 412 of file nbd-server.c.

References DEBUG, and err().

Referenced by mainloop().

Variable Documentation

GHashTable* children

Definition at line 178 of file nbd-server.c.

Referenced by serveloop(), setup_servers(), sigchld_handler(), and sigterm_handler().

gchar* config_file_pos

Where our config file actually is.

Definition at line 116 of file nbd-server.c.

Referenced by cmdline(), and main().

char default_authname[] = SYSCONFDIR "/nbd-server/allow"

default name of allow file

Definition at line 181 of file nbd-server.c.

Referenced by cmdline().

int dontfork = 0

Definition at line 126 of file nbd-server.c.

Referenced by cmdline(), main(), and serveloop().

int glob_flags =0

global flags

Definition at line 123 of file nbd-server.c.

Referenced by cmdline(), handle_list(), parse_cfile(), and setup_serve().

bool logged_oversized =false

whether we logged oversized requests already

Definition at line 196 of file nbd-server.c.

Referenced by mainloop().

char* modern_listen

listenaddr value for modernsock

Definition at line 192 of file nbd-server.c.

Referenced by open_modern(), and parse_cfile().

char* modernport =NBD_DEFAULT_PORT

Port number on which to listen for new-style nbd-client connections.

Definition at line 193 of file nbd-server.c.

Referenced by open_modern(), and parse_cfile().

int modernsock =0

Socket for the modern handler.

Not used if a client was only specified on the command line; only port used if oldstyle is set to false (and then the command-line client isn't used, gna gna)

Definition at line 187 of file nbd-server.c.

Referenced by open_modern(), and serveloop().

char pidfname[256]

name of our PID file

Definition at line 179 of file nbd-server.c.

Referenced by daemonize(), and sigterm_handler().

char pidftemplate[256]

template to be used for the filename of the PID file

Definition at line 180 of file nbd-server.c.

Referenced by cmdline(), daemonize(), and main().

gchar* rungroup =NULL

What group we're running as.