mountd.c

早期freebsd实现

	}
	*naddrp = (char *)NULL;
	if (debug)
		fprintf(stderr, "got host %s\n", hp->h_name);
	return (0);
}

/*
 * Free up an exports list component
 */
void
free_exp(ep)
	struct exportlist *ep;
{

	if (ep->ex_defdir) {
		free_host(ep->ex_defdir->dp_hosts);
		free((caddr_t)ep->ex_defdir);
	}
	if (ep->ex_fsdir)
		free(ep->ex_fsdir);
	free_dir(ep->ex_dirl);
	free((caddr_t)ep);
}

/*
 * Free hosts.
 */
void
free_host(hp)
	struct hostlist *hp;
{
	struct hostlist *hp2;

	while (hp) {
		hp2 = hp;
		hp = hp->ht_next;
		free((caddr_t)hp2);
	}
}

struct hostlist *
get_ht()
{
	struct hostlist *hp;

	hp = (struct hostlist *)malloc(sizeof (struct hostlist));
	if (hp == (struct hostlist *)NULL)
		out_of_mem();
	hp->ht_next = (struct hostlist *)NULL;
	return (hp);
}

#ifdef ISO
/*
 * Translate an iso address.
 */
get_isoaddr(cp, grp)
	char *cp;
	struct grouplist *grp;
{
	struct iso_addr *isop;
	struct sockaddr_iso *isoaddr;

	if (grp->gr_type != GT_NULL)
		return (1);
	if ((isop = iso_addr(cp)) == NULL) {
		syslog(LOG_ERR,
		    "iso_addr failed, ignored");
		return (1);
	}
	isoaddr = (struct sockaddr_iso *)
	    malloc(sizeof (struct sockaddr_iso));
	if (isoaddr == (struct sockaddr_iso *)NULL)
		out_of_mem();
	bzero((caddr_t)isoaddr, sizeof (struct sockaddr_iso));
	bcopy((caddr_t)isop, (caddr_t)&isoaddr->siso_addr,
		sizeof (struct iso_addr));
	isoaddr->siso_len = sizeof (struct sockaddr_iso);
	isoaddr->siso_family = AF_ISO;
	grp->gr_type = GT_ISO;
	grp->gr_ptr.gt_isoaddr = isoaddr;
	return (0);
}
#endif	/* ISO */

/*
 * Out of memory, fatal
 */
void
out_of_mem()
{

	syslog(LOG_ERR, "Out of memory");
	exit(2);
}

/*
 * Do the mount syscall with the update flag to push the export info into
 * the kernel.
 */
int
do_mount(ep, grp, exflags, anoncrp, dirp, dirplen, fsb)
	struct exportlist *ep;
	struct grouplist *grp;
	int exflags;
	struct ucred *anoncrp;
	char *dirp;
	int dirplen;
	struct statfs *fsb;
{
	char *cp = (char *)NULL;
	u_long **addrp;
	int done;
	char savedc = '\0';
	struct sockaddr_in sin, imask;
	union {
		struct ufs_args ua;
		struct iso_args ia;
		struct mfs_args ma;
	} args;
	u_long net;

	args.ua.fspec = 0;
	args.ua.export.ex_flags = exflags;
	args.ua.export.ex_anon = *anoncrp;
	bzero((char *)&sin, sizeof(sin));
	bzero((char *)&imask, sizeof(imask));
	sin.sin_family = AF_INET;
	sin.sin_len = sizeof(sin);
	imask.sin_family = AF_INET;
	imask.sin_len = sizeof(sin);
	if (grp->gr_type == GT_HOST)
		addrp = (u_long **)grp->gr_ptr.gt_hostent->h_addr_list;
	else
		addrp = (u_long **)NULL;
	done = FALSE;
	while (!done) {
		switch (grp->gr_type) {
		case GT_HOST:
			if (addrp) {
				sin.sin_addr.s_addr = **addrp;
				args.ua.export.ex_addrlen = sizeof(sin);
			} else
				args.ua.export.ex_addrlen = 0;
			args.ua.export.ex_addr = (struct sockaddr *)&sin;
			args.ua.export.ex_masklen = 0;
			break;
		case GT_NET:
			if (grp->gr_ptr.gt_net.nt_mask)
			    imask.sin_addr.s_addr = grp->gr_ptr.gt_net.nt_mask;
			else {
			    net = ntohl(grp->gr_ptr.gt_net.nt_net);
			    if (IN_CLASSA(net))
				imask.sin_addr.s_addr = inet_addr("255.0.0.0");
			    else if (IN_CLASSB(net))
				imask.sin_addr.s_addr =
				    inet_addr("255.255.0.0");
			    else
				imask.sin_addr.s_addr =
				    inet_addr("255.255.255.0");
			    grp->gr_ptr.gt_net.nt_mask = imask.sin_addr.s_addr;
			}
			sin.sin_addr.s_addr = grp->gr_ptr.gt_net.nt_net;
			args.ua.export.ex_addr = (struct sockaddr *)&sin;
			args.ua.export.ex_addrlen = sizeof (sin);
			args.ua.export.ex_mask = (struct sockaddr *)&imask;
			args.ua.export.ex_masklen = sizeof (imask);
			break;
#ifdef ISO
		case GT_ISO:
			args.ua.export.ex_addr =
				(struct sockaddr *)grp->gr_ptr.gt_isoaddr;
			args.ua.export.ex_addrlen =
				sizeof(struct sockaddr_iso);
			args.ua.export.ex_masklen = 0;
			break;
#endif	/* ISO */
		default:
			syslog(LOG_ERR, "Bad grouptype");
			if (cp)
				*cp = savedc;
			return (1);
		};

		/*
		 * XXX:
		 * Maybe I should just use the fsb->f_mntonname path instead
		 * of looping back up the dirp to the mount point??
		 * Also, needs to know how to export all types of local
		 * exportable file systems and not just MOUNT_UFS.
		 */
		while (mount(fsb->f_type, dirp,
		       fsb->f_flags | MNT_UPDATE, (caddr_t)&args) < 0) {
			if (cp)
				*cp-- = savedc;
			else
				cp = dirp + dirplen - 1;
			if (errno == EPERM) {
				syslog(LOG_ERR,
				   "Can't change attributes for %s.\n", dirp);
				return (1);
			}
			if (opt_flags & OP_ALLDIRS) {
				syslog(LOG_ERR, "Not root dir");
				return (1);
			}
			/* back up over the last component */
			while (*cp == '/' && cp > dirp)
				cp--;
			while (*(cp - 1) != '/' && cp > dirp)
				cp--;
			if (cp == dirp) {
				if (debug)
					fprintf(stderr,"mnt unsucc\n");
				syslog(LOG_ERR, "Can't export %s", dirp);
				return (1);
			}
			savedc = *cp;
			*cp = '\0';
		}
		if (addrp) {
			++addrp;
			if (*addrp == (u_long *)NULL)
				done = TRUE;
		} else
			done = TRUE;
	}
	if (cp)
		*cp = savedc;
	return (0);
}

/*
 * Translate a net address.
 */
int
get_net(cp, net, maskflg)
	char *cp;
	struct netmsk *net;
	int maskflg;
{
	struct netent *np;
	long netaddr;
	struct in_addr inetaddr, inetaddr2;
	char *name;

	if (np = getnetbyname(cp))
		inetaddr = inet_makeaddr(np->n_net, 0);
	else if (isdigit(*cp)) {
		if ((netaddr = inet_network(cp)) == -1)
			return (1);
		inetaddr = inet_makeaddr(netaddr, 0);
		/*
		 * Due to arbritrary subnet masks, you don't know how many
		 * bits to shift the address to make it into a network,
		 * however you do know how to make a network address into
		 * a host with host == 0 and then compare them.
		 * (What a pest)
		 */
		if (!maskflg) {
			setnetent(0);
			while (np = getnetent()) {
				inetaddr2 = inet_makeaddr(np->n_net, 0);
				if (inetaddr2.s_addr == inetaddr.s_addr)
					break;
			}
			endnetent();
		}
	} else
		return (1);
	if (maskflg)
		net->nt_mask = inetaddr.s_addr;
	else {
		if (np)
			name = np->n_name;
		else
			name = inet_ntoa(inetaddr);
		net->nt_name = (char *)malloc(strlen(name) + 1);
		if (net->nt_name == (char *)NULL)
			out_of_mem();
		strcpy(net->nt_name, name);
		net->nt_net = inetaddr.s_addr;
	}
	return (0);
}

/*
 * Parse out the next white space separated field
 */
void
nextfield(cp, endcp)
	char **cp;
	char **endcp;
{
	char *p;

	p = *cp;
	while (*p == ' ' || *p == '\t')
		p++;
	if (*p == '\n' || *p == '\0')
		*cp = *endcp = p;
	else {
		*cp = p++;
		while (*p != ' ' && *p != '\t' && *p != '\n' && *p != '\0')
			p++;
		*endcp = p;
	}
}

/*
 * Get an exports file line. Skip over blank lines and handle line
 * continuations.
 */
int
get_line()
{
	char *p, *cp;
	int len;
	int totlen, cont_line;

	/*
	 * Loop around ignoring blank lines and getting all continuation lines.
	 */
	p = line;
	totlen = 0;
	do {
		if (fgets(p, LINESIZ - totlen, exp_file) == NULL)
			return (0);
		len = strlen(p);
		cp = p + len - 1;
		cont_line = 0;
		while (cp >= p &&
		    (*cp == ' ' || *cp == '\t' || *cp == '\n' || *cp == '\\')) {
			if (*cp == '\\')
				cont_line = 1;
			cp--;
			len--;
		}
		*++cp = '\0';
		if (len > 0) {
			totlen += len;
			if (totlen >= LINESIZ) {
				syslog(LOG_ERR, "Exports line too long");
				exit(2);
			}
			p = cp;
		}
	} while (totlen == 0 || cont_line);
	return (1);
}

/*
 * Parse a description of a credential.
 */
void
parsecred(namelist, cr)
	char *namelist;
	struct ucred *cr;
{
	char *name;
	int cnt;
	char *names;
	struct passwd *pw;
	struct group *gr;
	int ngroups, groups[NGROUPS + 1];

	/*
	 * Set up the unpriviledged user.
	 */
	cr->cr_ref = 1;
	cr->cr_uid = -2;
	cr->cr_groups[0] = -2;
	cr->cr_ngroups = 1;
	/*
	 * Get the user's password table entry.
	 */
	names = strsep(&namelist, " \t\n");
	name = strsep(&names, ":");
	if (isdigit(*name) || *name == '-')
		pw = getpwuid(atoi(name));
	else
		pw = getpwnam(name);
	/*
	 * Credentials specified as those of a user.
	 */
	if (names == NULL) {
		if (pw == NULL) {
			syslog(LOG_ERR, "Unknown user: %s", name);
			return;
		}
		cr->cr_uid = pw->pw_uid;
		ngroups = NGROUPS + 1;
		if (getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups))
			syslog(LOG_ERR, "Too many groups");
		/*
		 * Convert from int's to gid_t's and compress out duplicate
		 */
		cr->cr_ngroups = ngroups - 1;
		cr->cr_groups[0] = groups[0];
		for (cnt = 2; cnt < ngroups; cnt++)
			cr->cr_groups[cnt - 1] = groups[cnt];
		return;
	}
	/*
	 * Explicit credential specified as a colon separated list:
	 *	uid:gid:gid:...
	 */
	if (pw != NULL)
		cr->cr_uid = pw->pw_uid;
	else if (isdigit(*name) || *name == '-')
		cr->cr_uid = atoi(name);
	else {
		syslog(LOG_ERR, "Unknown user: %s", name);
		return;
	}
	cr->cr_ngroups = 0;
	while (names != NULL && *names != '\0' && cr->cr_ngroups < NGROUPS) {
		name = strsep(&names, ":");
		if (isdigit(*name) || *name == '-') {
			cr->cr_groups[cr->cr_ngroups++] = atoi(name);
		} else {
			if ((gr = getgrnam(name)) == NULL) {
				syslog(LOG_ERR, "Unknown group: %s", name);
				continue;
			}
			cr->cr_groups[cr->cr_ngroups++] = gr->gr_gid;
		}
	}
	if (names != NULL && *names != '\0' && cr->cr_ngroups == NGROUPS)
		syslog(LOG_ERR, "Too many groups");
}

#define	STRSIZ	(RPCMNT_NAMELEN+RPCMNT_PATHLEN+50)
/*
 * Routines that maintain the remote mounttab
 */
void
get_mountlist()
{
	struct mountlist *mlp, **mlpp;
	char *eos, *dirp;
	int len;
	char str[STRSIZ];
	FILE *mlfile;

	if ((mlfile = fopen(_PATH_RMOUNTLIST, "r")) == NULL) {
		syslog(LOG_ERR, "Can't open %s", _PATH_RMOUNTLIST);
		return;
	}
	mlpp = &mlhead;
	while (fgets(str, STRSIZ, mlfile) != NULL) {
		if ((dirp = index(str, '\t')) == NULL &&
		    (dirp = index(str, ' ')) == NULL)
			continue;
		mlp = (struct mountlist *)malloc(sizeof (*mlp));
		len = dirp-str;
		if (len > RPCMNT_NAMELEN)
			len = RPCMNT_NAMELEN;
		bcopy(str, mlp->ml_host, len);
		mlp->ml_host[len] = '\0';
		while (*dirp == '\t' || *dirp == ' ')
			dirp++;
		if ((eos = index(dirp, '\t')) == NULL &&
		    (eos = index(dirp, ' ')) == NULL &&
		    (eos = index(dirp, '\n')) == NULL)
			len = strlen(dirp);
		else
			len = eos-dirp;
		if (len > RPCMNT_PATHLEN)
			len = RPCMNT_PATHLEN;
		bcopy(dirp, mlp->ml_dirp, len);
		mlp->ml_dirp[len] = '\0';
		mlp->ml_next = (struct mountlist *)NULL;
		*mlpp = mlp;
		mlpp = &mlp->ml_next;
	}
	fclose(mlfile);
}

void
del_mlist(hostp, dirp)
	char *hostp, *dirp;
{
	struct mountlist *mlp, **mlpp;
	struct mountlist *mlp2;
	FILE *mlfile;
	int fnd = 0;

	mlpp = &mlhead;
	mlp = mlhead;
	while (mlp) {
		if (!strcmp(mlp->ml_host, hostp) &&
		    (!dirp || !strcmp(mlp->ml_dirp, dirp))) {
			fnd = 1;
			mlp2 = mlp;
			*mlpp = mlp = mlp->ml_next;
			free((caddr_t)mlp2);
		} else {
			mlpp = &mlp->ml_next;
			mlp = mlp->ml_next;
		}
	}
	if (fnd) {
		if ((mlfile = fopen(_PATH_RMOUNTLIST, "w")) == NULL) {
			syslog(LOG_ERR,"Can't update %s", _PATH_RMOUNTLIST);
			return;
		}
		mlp = mlhead;
		while (mlp) {
			fprintf(mlfile, "%s %s\n", mlp->ml_host, mlp->ml_dirp);
			mlp = mlp->ml_next;
		}
		fclose(mlfile);
	}
}

void
add_mlist(hostp, dirp)
	char *hostp, *dirp;
{
	struct mountlist *mlp, **mlpp;
	FILE *mlfile;

	mlpp = &mlhead;
	mlp = mlhead;
	while (mlp) {
		if (!strcmp(mlp->ml_host, hostp) && !strcmp(mlp->ml_dirp, dirp))
			return;
		mlpp = &mlp->ml_next;
		mlp = mlp->ml_next;
	}
	mlp = (struct mountlist *)malloc(sizeof (*mlp));
	strncpy(mlp->ml_host, hostp, RPCMNT_NAMELEN);
	mlp->ml_host[RPCMNT_NAMELEN] = '\0';
	strncpy(mlp->ml_dirp, dirp, RPCMNT_PATHLEN);
	mlp->ml_dirp[RPCMNT_PATHLEN] = '\0';
	mlp->ml_next = (struct mountlist *)NULL;
	*mlpp = mlp;
	if ((mlfile = fopen(_PATH_RMOUNTLIST, "a")) == NULL) {
		syslog(LOG_ERR, "Can't update %s", _PATH_RMOUNTLIST);
		return;
	}
	fprintf(mlfile, "%s %s\n", mlp->ml_host, mlp->ml_dirp);
	fclose(mlfile);
}

/*
 * This function is called via. SIGTERM when the system is going down.
 * It sends a broadcast RPCMNT_UMNTALL.
 */
void
send_umntall()
{
	(void) clnt_broadcast(RPCPROG_MNT, RPCMNT_VER1, RPCMNT_UMNTALL,
		xdr_void, (caddr_t)0, xdr_void, (caddr_t)0, umntall_each);
	exit(0);
}

int
umntall_each(resultsp, raddr)
	caddr_t resultsp;
	struct sockaddr_in *raddr;
{
	return (1);
}

/*
 * Free up a group list.
 */
void
free_grp(grp)
	struct grouplist *grp;
{
	char **addrp;

	if (grp->gr_type == GT_HOST) {
		if (grp->gr_ptr.gt_hostent->h_name) {
			addrp = grp->gr_ptr.gt_hostent->h_addr_list;
			while (addrp && *addrp)
				free(*addrp++);
			free((caddr_t)grp->gr_ptr.gt_hostent->h_addr_list);
			free(grp->gr_ptr.gt_hostent->h_name);
		}
		free((caddr_t)grp->gr_ptr.gt_hostent);
	} else if (grp->gr_type == GT_NET) {
		if (grp->gr_ptr.gt_net.nt_name)
			free(grp->gr_ptr.gt_net.nt_name);
	}
#ifdef ISO
	else if (grp->gr_type == GT_ISO)
		free((caddr_t)grp->gr_ptr.gt_isoaddr);
#endif
	free((caddr_t)grp);
}

#ifdef DEBUG
void
SYSLOG(int pri, const char *fmt, ...)
{
	va_list ap;

	va_start(ap, fmt);
	vfprintf(stderr, fmt, ap);
	va_end(ap);
}
#endif /* DEBUG */

/*
 * Check options for consistency.
 */
int
check_options(dp)
	struct dirlist *dp;
{

	if (dp == (struct dirlist *)NULL)
	    return (1);
	if ((opt_flags & (OP_MAPROOT | OP_MAPALL)) == (OP_MAPROOT | OP_MAPALL) ||
	    (opt_flags & (OP_MAPROOT | OP_KERB)) == (OP_MAPROOT | OP_KERB) ||
	    (opt_flags & (OP_MAPALL | OP_KERB)) == (OP_MAPALL | OP_KERB)) {
	    syslog(LOG_ERR, "-mapall, -maproot and -kerb mutually exclusive");
	    return (1);
	}
	if ((opt_flags & OP_MASK) && (opt_flags & OP_NET) == 0) {
	    syslog(LOG_ERR, "-mask requires -net");
	    return (1);
	}
	if ((opt_flags & (OP_NET | OP_ISO)) == (OP_NET | OP_ISO)) {
	    syslog(LOG_ERR, "-net and -iso mutually exclusive");
	    return (1);
	}
	if ((opt_flags & OP_ALLDIRS) && dp->dp_left) {
	    syslog(LOG_ERR, "-alldir has multiple directories");
	    return (1);
	}
	return (0);
}

/*
 * Check an absolute directory path for any symbolic links. Return true
 * if no symbolic links are found.
 */
int
check_dirpath(dirp)
	char *dirp;
{
	char *cp;
	int ret = 1;
	struct stat sb;

	cp = dirp + 1;
	while (*cp && ret) {
		if (*cp == '/') {
			*cp = '\0';
			if (lstat(dirp, &sb) < 0 ||
				(sb.st_mode & S_IFMT) != S_IFDIR)
				ret = 0;
			*cp = '/';
		}
		cp++;
	}
	if (lstat(dirp, &sb) < 0 ||
		(sb.st_mode & S_IFMT) != S_IFDIR)
		ret = 0;
	return (ret);
}