nfsmount.c

linux mount的源代码

/* vi: set sw=4 ts=4: */
/*
 * nfsmount.c -- Linux NFS mount
 * Copyright (C) 1993 Rick Sladkey <[e-mail]>
 *
 * 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, 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.
 *
 * Wed Feb  8 12:51:48 1995, [e-mail] (Ross Biro): allow all port
 * numbers to be specified on the command line.
 *
 * Fri, 8 Mar 1996 18:01:39, Swen Thuemmler <[e-mail]>:
 * Omit the call to connect() for Linux version 1.3.11 or later.
 *
 * Wed Oct  1 23:55:28 1997: Dick Streefland <[e-mail]>
 * Implemented the "bg", "fg" and "retry" mount options for NFS.
 *
 * 1999-02-22 Arkadiusz Mi秌iewicz <[e-mail]>
 * - added Native Language Support
 * 
 * Modified by Olaf Kirch and Trond Myklebust for new NFS code,
 * plus NFSv3 stuff.
 */

/*
 * nfsmount.c,v 1.1.1.1 1993/11/18 08:40:51 jrs Exp
 */

#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <netdb.h>
#include <sys/socket.h>
#include <time.h>
#include <sys/utsname.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdlib.h>
#include <sys/stat.h>
#undef TRUE
#undef FALSE
#include <rpc/rpc.h>
#include <rpc/pmap_prot.h>
#include <rpc/pmap_clnt.h>
#include <linux/nfs.h>  /* For the kernels nfs stuff */
#include "nfsmount.h"

#define error_msg(arg...)	fprintf(stderr, arg)

#ifndef NFS_FHSIZE
static const int NFS_FHSIZE = 32;
#endif
#ifndef NFS_PORT
static const int NFS_PORT = 2049;
#endif

/* the bug of tool chain */
#define  TOOL_CHAIN
#ifdef   TOOL_CHAIN
#include <rpc/types.h>
#include <rpc/xdr.h>
/*
 * constants specific to the xdr "protocol"
 */
#define XDR_FALSE       ((long) 0)
#define XDR_TRUE        ((long) 1)
#define LASTUNSIGNED    ((u_int) 0-1)
/*
 * These are the "generic" xdr routines.
 */
bool_t   _xdr_int();
#endif     /*TOOL_CHAIN*/

/* Disable the nls stuff */
# undef bindtextdomain
# define bindtextdomain(Domain, Directory) /* empty */
# undef textdomain
# define textdomain(Domain) /* empty */
# define _(Text) (Text)
# define N_(Text) (Text)

static const int MS_MGC_VAL = 0xc0ed0000; /* Magic number indicatng "new" flags */
static const int MS_RDONLY = 1;      /* Mount read-only */
static const int MS_NOSUID = 2;      /* Ignore suid and sgid bits */
static const int MS_NODEV = 4;      /* Disallow access to device special files */
static const int MS_NOEXEC = 8;      /* Disallow program execution */
static const int MS_SYNCHRONOUS = 16;      /* Writes are synced at once */
static const int MS_REMOUNT = 32;      /* Alter flags of a mounted FS */
static const int MS_MANDLOCK = 64;      /* Allow mandatory locks on an FS */
static const int S_QUOTA = 128;     /* Quota initialized for file/directory/symlink */
static const int S_APPEND = 256;     /* Append-only file */
static const int S_IMMUTABLE = 512;     /* Immutable file */
static const int MS_NOATIME = 1024;    /* Do not update access times. */
static const int MS_NODIRATIME = 2048;    /* Do not update directory access times */


/*
 * We want to be able to compile mount on old kernels in such a way
 * that the binary will work well on more recent kernels.
 * Thus, if necessary we teach nfsmount.c the structure of new fields
 * that will come later.
 *
 * Moreover, the new kernel includes conflict with glibc includes
 * so it is easiest to ignore the kernel altogether (at compile time).
 */

/* NOTE: Do not make this into a 'static const int' because the pre-processor
 * needs to test this value in some #if statements. */
#define NFS_MOUNT_VERSION 4

struct nfs2_fh {
        char                    data[32];
};
struct nfs3_fh {
        unsigned short          size;
        unsigned char           data[64];
};

struct nfs_mount_data {
	int		version;		/* 1 */
	int		fd;			/* 1 */
	struct nfs2_fh	old_root;		/* 1 */
	int		flags;			/* 1 */
	int		rsize;			/* 1 */
	int		wsize;			/* 1 */
	int		timeo;			/* 1 */
	int		retrans;		/* 1 */
	int		acregmin;		/* 1 */
	int		acregmax;		/* 1 */
	int		acdirmin;		/* 1 */
	int		acdirmax;		/* 1 */
	struct sockaddr_in addr;		/* 1 */
	char		hostname[256];		/* 1 */
	int		namlen;			/* 2 */
	unsigned int	bsize;			/* 3 */
	struct nfs3_fh	root;			/* 4 */
};

/* bits in the flags field */

static const int NFS_MOUNT_SOFT = 0x0001;	/* 1 */
static const int NFS_MOUNT_INTR = 0x0002;	/* 1 */
static const int NFS_MOUNT_SECURE = 0x0004;	/* 1 */
static const int NFS_MOUNT_POSIX = 0x0008;	/* 1 */
static const int NFS_MOUNT_NOCTO = 0x0010;	/* 1 */
static const int NFS_MOUNT_NOAC = 0x0020;	/* 1 */
static const int NFS_MOUNT_TCP = 0x0040;	/* 2 */
static const int NFS_MOUNT_VER3 = 0x0080;	/* 3 */
static const int NFS_MOUNT_KERBEROS = 0x0100;	/* 3 */
static const int NFS_MOUNT_NONLM = 0x0200;	/* 3 */


#define UTIL_LINUX_VERSION "2.10m"
#define util_linux_version "util-linux-2.10m"

#define HAVE_inet_aton
#define HAVE_scsi_h
#define HAVE_blkpg_h
#define HAVE_kd_h
#define HAVE_termcap
#define HAVE_locale_h
#define HAVE_libintl_h
#define ENABLE_NLS
#define HAVE_langinfo_h
#define HAVE_progname
#define HAVE_openpty
#define HAVE_nanosleep
#define HAVE_personality
#define HAVE_tm_gmtoff

static char *nfs_strerror(int status);

#define MAKE_VERSION(p,q,r)	(65536*(p) + 256*(q) + (r))
#define MAX_NFSPROT ((nfs_mount_version >= 4) ? 3 : 2)

static const int EX_FAIL = 32;       /* mount failure */
static const int EX_BG = 256;       /* retry in background (internal only) */

char *xstrdup (const char *s);
char *xstrndup (const char *s, int n);

#define MAKE_VERSION(p,q,r)	(65536*(p) + 256*(q) + (r))

static int
get_kernel_revision(void) {
	struct utsname my_utsname;
	int p, q, r;

	if (uname(&my_utsname) == 0) {
		p = atoi(strtok(my_utsname.release, "."));
		q = atoi(strtok(NULL, "."));
		r = atoi(strtok(NULL, "."));
		return MAKE_VERSION(p,q,r);
	}
	return 0;
}

/*
 * nfs_mount_version according to the sources seen at compile time.
 */
static int nfs_mount_version;

/*
 * Unfortunately, the kernel prints annoying console messages
 * in case of an unexpected nfs mount version (instead of
 * just returning some error).  Therefore we'll have to try
 * and figure out what version the kernel expects.
 *
 * Variables:
 *	KERNEL_NFS_MOUNT_VERSION: kernel sources at compile time
 *	NFS_MOUNT_VERSION: these nfsmount sources at compile time
 *	nfs_mount_version: version this source and running kernel can handle
 */
static void
find_kernel_nfs_mount_version(void)
{
	static int kernel_version = 0;

	if (kernel_version)
		return;

	nfs_mount_version = NFS_MOUNT_VERSION; /* default */

	kernel_version = get_kernel_revision();
	if (kernel_version) {
		if (kernel_version < MAKE_VERSION(2,1,32))
			nfs_mount_version = 1;
		else if (kernel_version < MAKE_VERSION(2,2,18) ||
				(kernel_version >=   MAKE_VERSION(2,3,0) &&
				 kernel_version < MAKE_VERSION(2,3,99)))
			nfs_mount_version = 3;
		else
			nfs_mount_version = 4; /* since 2.3.99pre4 */
	}
	if (nfs_mount_version > NFS_MOUNT_VERSION)
		nfs_mount_version = NFS_MOUNT_VERSION;
}

static struct pmap *
get_mountport(struct sockaddr_in *server_addr,
      long unsigned prog,
      long unsigned version,
      long unsigned proto,
      long unsigned port)
{
struct pmaplist *pmap;
static struct pmap p = {0, 0, 0, 0};

server_addr->sin_port = PMAPPORT;
pmap = pmap_getmaps(server_addr);

if (version > MAX_NFSPROT)
	version = MAX_NFSPROT;
if (!prog)
	prog = MOUNTPROG;
p.pm_prog = prog;
p.pm_vers = version;
p.pm_prot = proto;
p.pm_port = port;

while (pmap) {
	if (pmap->pml_map.pm_prog != prog)
		goto next;
	if (!version && p.pm_vers > pmap->pml_map.pm_vers)
		goto next;
	if (version > 2 && pmap->pml_map.pm_vers != version)
		goto next;
	if (version && version <= 2 && pmap->pml_map.pm_vers > 2)
		goto next;
	if (pmap->pml_map.pm_vers > MAX_NFSPROT ||
	    (proto && p.pm_prot && pmap->pml_map.pm_prot != proto) ||
	    (port && pmap->pml_map.pm_port != port))
		goto next;
	memcpy(&p, &pmap->pml_map, sizeof(p));
next:
	pmap = pmap->pml_next;
}
if (!p.pm_vers)
	p.pm_vers = MOUNTVERS;
if (!p.pm_port)
	p.pm_port = MOUNTPORT;
if (!p.pm_prot)
	p.pm_prot = IPPROTO_TCP;
return &p;
}

int nfsmount(const char *spec, const char *node, int *flags,
	     char **extra_opts, char **mount_opts, int running_bg)
{
	static char *prev_bg_host;
	char hostdir[1024];
	CLIENT *mclient;
	char *hostname;
	char *dirname;
	char *old_opts;
	char *mounthost=NULL;
	char new_opts[1024];
	struct timeval total_timeout;
	enum clnt_stat clnt_stat;
	static struct nfs_mount_data data;
	char *opt, *opteq;
	int val;
	struct hostent *hp;
	struct sockaddr_in server_addr;
	struct sockaddr_in mount_server_addr;
	struct pmap* pm_mnt;
	int msock, fsock;
	struct timeval retry_timeout;
	union {
		struct fhstatus nfsv2;
		struct mountres3 nfsv3;
	} status;
	struct stat statbuf;
	char *s;
	int port;
	int mountport;
	int proto;
	int bg;
	int soft;
	int intr;
	int posix;
	int nocto;
	int noac;
	int nolock;
	int retry;
	int tcp;
	int mountprog;
	int mountvers;
	int nfsprog;
	int nfsvers;
	int retval;
	time_t t;
	time_t prevt;
	time_t timeout;

	find_kernel_nfs_mount_version();

	retval = EX_FAIL;
	msock = fsock = -1;
	mclient = NULL;
	if (strlen(spec) >= sizeof(hostdir)) {
		error_msg("excessively long host:dir argument");
		goto fail;
	}
	strcpy(hostdir, spec);
	if ((s = strchr(hostdir, ':'))) {
		hostname = hostdir;
		dirname = s + 1;
		*s = '\0';
		/* Ignore all but first hostname in replicated mounts
		   until they can be fully supported. ([e-mail]) */
		if ((s = strchr(hostdir, ','))) {
			*s = '\0';
			error_msg("warning: multiple hostnames not supported");
		}
	} else {
		error_msg("directory to mount not in host:dir format");
		goto fail;
	}

	server_addr.sin_family = AF_INET;
#ifdef HAVE_inet_aton
	if (!inet_aton(hostname, &server_addr.sin_addr))
#endif
	{
#ifdef NO_GETHOSTBYNAME
		fprintf(stderr, "ERROR (%d): no gethostbyname()\n", __LINE__);
#else
		if ((hp = gethostbyname(hostname)) == NULL) {
			error_msg("can't get address for %s", hostname);
			goto fail;
		} else {
			if (hp->h_length > sizeof(struct in_addr)) {
				error_msg("got bad hp->h_length");
				hp->h_length = sizeof(struct in_addr);
			}
			memcpy(&server_addr.sin_addr,
			       hp->h_addr, hp->h_length);
		}
#endif
	}

	memcpy (&mount_server_addr, &server_addr, sizeof (mount_server_addr));

	/* add IP address to mtab options for use when unmounting */

	s = inet_ntoa(server_addr.sin_addr);
	old_opts = *extra_opts;
	if (!old_opts)
		old_opts = "";
	if (strlen(old_opts) + strlen(s) + 10 >= sizeof(new_opts)) {
		error_msg("excessively long option argument");
		goto fail;
	}
	sprintf(new_opts, "%s%saddr=%s",
		old_opts, *old_opts ? "," : "", s);
	*extra_opts = xstrdup(new_opts);

	/* Set default options.
	 * rsize/wsize (and bsize, for ver >= 3) are left 0 in order to
	 * let the kernel decide.
	 * timeo is filled in after we know whether it'll be TCP or UDP. */
	memset(&data, 0, sizeof(data));
	data.retrans	= 3;
	data.acregmin	= 3;
	data.acregmax	= 60;
	data.acdirmin	= 30;
	data.acdirmax	= 60;
#if NFS_MOUNT_VERSION >= 2
	data.namlen	= NAME_MAX;
#endif

	bg = 0;
	soft = 0;
	intr = 0;
	posix = 0;
	nocto = 0;
	nolock = 0;
	noac = 0;
	retry = 10000;		/* 10000 minutes ~ 1 week */
	tcp = 0;

	mountprog = MOUNTPROG;
	mountvers = 0;
	port = 0;
	mountport = 0;
	nfsprog = NFS_PROGRAM;
	nfsvers = 0;

	/* parse options */

	for (opt = strtok(old_opts, ","); opt; opt = strtok(NULL, ",")) {
		if ((opteq = strchr(opt, '='))) {
			val = atoi(opteq + 1);	
			*opteq = '\0';
			if (!strcmp(opt, "rsize"))
				data.rsize = val;
			else if (!strcmp(opt, "wsize"))
				data.wsize = val;
			else if (!strcmp(opt, "timeo"))
				data.timeo = val;
			else if (!strcmp(opt, "retrans"))
				data.retrans = val;
			else if (!strcmp(opt, "acregmin"))
				data.acregmin = val;
			else if (!strcmp(opt, "acregmax"))
				data.acregmax = val;
			else if (!strcmp(opt, "acdirmin"))
				data.acdirmin = val;
			else if (!strcmp(opt, "acdirmax"))
				data.acdirmax = val;
			else if (!strcmp(opt, "actimeo")) {
				data.acregmin = val;
				data.acregmax = val;
				data.acdirmin = val;
				data.acdirmax = val;
			}
			else if (!strcmp(opt, "retry"))
				retry = val;
			else if (!strcmp(opt, "port"))
				port = val;
			else if (!strcmp(opt, "mountport"))
			        mountport = val;
			else if (!strcmp(opt, "mounthost"))
			        mounthost=xstrndup(opteq+1,
						  strcspn(opteq+1," \t\n\r,"));
			else if (!strcmp(opt, "mountprog"))
				mountprog = val;
			else if (!strcmp(opt, "mountvers"))
				mountvers = val;
			else if (!strcmp(opt, "nfsprog"))
				nfsprog = val;
			else if (!strcmp(opt, "nfsvers") ||
				 !strcmp(opt, "vers"))
				nfsvers = val;
			else if (!strcmp(opt, "proto")) {
				if (!strncmp(opteq+1, "tcp", 3))
					tcp = 1;
				else if (!strncmp(opteq+1, "udp", 3))
					tcp = 0;
				else
					printf(_("Warning: Unrecognized proto= option.\n"));
			} else if (!strcmp(opt, "namlen")) {
#if NFS_MOUNT_VERSION >= 2
				if (nfs_mount_version >= 2)
					data.namlen = val;
				else
#endif
				printf(_("Warning: Option namlen is not supported.\n"));
			} else if (!strcmp(opt, "addr"))
				/* ignore */;
			else {
				printf(_("unknown nfs mount parameter: "
				       "%s=%d\n"), opt, val);
				goto fail;
			}
		}
		else {
			val = 1;
			if (!strncmp(opt, "no", 2)) {
				val = 0;
				opt += 2;
			}
			if (!strcmp(opt, "bg")) 
				bg = val;
			else if (!strcmp(opt, "fg")) 
				bg = !val;
			else if (!strcmp(opt, "soft"))
				soft = val;
			else if (!strcmp(opt, "hard"))
				soft = !val;
			else if (!strcmp(opt, "intr"))
				intr = val;
			else if (!strcmp(opt, "posix"))
				posix = val;
			else if (!strcmp(opt, "cto"))