mountd.c

早期freebsd实现

			fprintf(stderr,"Got line %s\n",line);
		cp = line;
		nextfield(&cp, &endcp);
		if (*cp == '#')
			goto nextline;

		/*
		 * Set defaults.
		 */
		has_host = FALSE;
		anon = def_anon;
		exflags = MNT_EXPORTED;
		got_nondir = 0;
		opt_flags = 0;
		ep = (struct exportlist *)NULL;

		/*
		 * Create new exports list entry
		 */
		len = endcp-cp;
		tgrp = grp = get_grp();
		while (len > 0) {
			if (len > RPCMNT_NAMELEN) {
			    getexp_err(ep, tgrp);
			    goto nextline;
			}
			if (*cp == '-') {
			    if (ep == (struct exportlist *)NULL) {
				getexp_err(ep, tgrp);
				goto nextline;
			    }
			    if (debug)
				fprintf(stderr, "doing opt %s\n", cp);
			    got_nondir = 1;
			    if (do_opt(&cp, &endcp, ep, grp, &has_host,
				&exflags, &anon)) {
				getexp_err(ep, tgrp);
				goto nextline;
			    }
			} else if (*cp == '/') {
			    savedc = *endcp;
			    *endcp = '\0';
			    if (check_dirpath(cp) &&
				statfs(cp, &fsb) >= 0) {
				if (got_nondir) {
				    syslog(LOG_ERR, "Dirs must be first");
				    getexp_err(ep, tgrp);
				    goto nextline;
				}
				if (ep) {
				    if (ep->ex_fs.val[0] != fsb.f_fsid.val[0] ||
					ep->ex_fs.val[1] != fsb.f_fsid.val[1]) {
					getexp_err(ep, tgrp);
					goto nextline;
				    }
				} else {
				    /*
				     * See if this directory is already
				     * in the list.
				     */
				    ep = ex_search(&fsb.f_fsid);
				    if (ep == (struct exportlist *)NULL) {
					ep = get_exp();
					ep->ex_fs = fsb.f_fsid;
					ep->ex_fsdir = (char *)
					    malloc(strlen(fsb.f_mntonname) + 1);
					if (ep->ex_fsdir)
					    strcpy(ep->ex_fsdir,
						fsb.f_mntonname);
					else
					    out_of_mem();
					if (debug)
					  fprintf(stderr,
					      "Making new ep fs=0x%x,0x%x\n",
					      fsb.f_fsid.val[0],
					      fsb.f_fsid.val[1]);
				    } else if (debug)
					fprintf(stderr,
					    "Found ep fs=0x%x,0x%x\n",
					    fsb.f_fsid.val[0],
					    fsb.f_fsid.val[1]);
				}

				/*
				 * Add dirpath to export mount point.
				 */
				dirp = add_expdir(&dirhead, cp, len);
				dirplen = len;
			    } else {
				getexp_err(ep, tgrp);
				goto nextline;
			    }
			    *endcp = savedc;
			} else {
			    savedc = *endcp;
			    *endcp = '\0';
			    got_nondir = 1;
			    if (ep == (struct exportlist *)NULL) {
				getexp_err(ep, tgrp);
				goto nextline;
			    }

			    /*
			     * Get the host or netgroup.
			     */
			    setnetgrent(cp);
			    netgrp = getnetgrent(&hst, &usr, &dom);
			    do {
				if (has_host) {
				    grp->gr_next = get_grp();
				    grp = grp->gr_next;
				}
				if (netgrp) {
				    if (get_host(hst, grp)) {
					syslog(LOG_ERR, "Bad netgroup %s", cp);
					getexp_err(ep, tgrp);
					goto nextline;
				    }
				} else if (get_host(cp, grp)) {
				    getexp_err(ep, tgrp);
				    goto nextline;
				}
				has_host = TRUE;
			    } while (netgrp && getnetgrent(&hst, &usr, &dom));
			    endnetgrent();
			    *endcp = savedc;
			}
			cp = endcp;
			nextfield(&cp, &endcp);
			len = endcp - cp;
		}
		if (check_options(dirhead)) {
			getexp_err(ep, tgrp);
			goto nextline;
		}
		if (!has_host) {
			grp->gr_type = GT_HOST;
			if (debug)
				fprintf(stderr,"Adding a default entry\n");
			/* add a default group and make the grp list NULL */
			hpe = (struct hostent *)malloc(sizeof(struct hostent));
			if (hpe == (struct hostent *)NULL)
				out_of_mem();
			hpe->h_name = "Default";
			hpe->h_addrtype = AF_INET;
			hpe->h_length = sizeof (u_long);
			hpe->h_addr_list = (char **)NULL;
			grp->gr_ptr.gt_hostent = hpe;

		/*
		 * Don't allow a network export coincide with a list of
		 * host(s) on the same line.
		 */
		} else if ((opt_flags & OP_NET) && tgrp->gr_next) {
			getexp_err(ep, tgrp);
			goto nextline;
		}

		/*
		 * Loop through hosts, pushing the exports into the kernel.
		 * After loop, tgrp points to the start of the list and
		 * grp points to the last entry in the list.
		 */
		grp = tgrp;
		do {
		    if (do_mount(ep, grp, exflags, &anon, dirp,
			dirplen, &fsb)) {
			getexp_err(ep, tgrp);
			goto nextline;
		    }
		} while (grp->gr_next && (grp = grp->gr_next));

		/*
		 * Success. Update the data structures.
		 */
		if (has_host) {
			hang_dirp(dirhead, tgrp, ep, (opt_flags & OP_ALLDIRS));
			grp->gr_next = grphead;
			grphead = tgrp;
		} else {
			hang_dirp(dirhead, (struct grouplist *)NULL, ep,
			(opt_flags & OP_ALLDIRS));
			free_grp(grp);
		}
		dirhead = (struct dirlist *)NULL;
		if ((ep->ex_flag & EX_LINKED) == 0) {
			ep2 = exphead;
			epp = &exphead;

			/*
			 * Insert in the list in alphabetical order.
			 */
			while (ep2 && strcmp(ep2->ex_fsdir, ep->ex_fsdir) < 0) {
				epp = &ep2->ex_next;
				ep2 = ep2->ex_next;
			}
			if (ep2)
				ep->ex_next = ep2;
			*epp = ep;
			ep->ex_flag |= EX_LINKED;
		}
nextline:
		if (dirhead) {
			free_dir(dirhead);
			dirhead = (struct dirlist *)NULL;
		}
	}
	fclose(exp_file);
}

/*
 * Allocate an export list element
 */
struct exportlist *
get_exp()
{
	struct exportlist *ep;

	ep = (struct exportlist *)malloc(sizeof (struct exportlist));
	if (ep == (struct exportlist *)NULL)
		out_of_mem();
	bzero((caddr_t)ep, sizeof (struct exportlist));
	return (ep);
}

/*
 * Allocate a group list element
 */
struct grouplist *
get_grp()
{
	struct grouplist *gp;

	gp = (struct grouplist *)malloc(sizeof (struct grouplist));
	if (gp == (struct grouplist *)NULL)
		out_of_mem();
	bzero((caddr_t)gp, sizeof (struct grouplist));
	return (gp);
}

/*
 * Clean up upon an error in get_exportlist().
 */
void
getexp_err(ep, grp)
	struct exportlist *ep;
	struct grouplist *grp;
{
	struct grouplist *tgrp;

	syslog(LOG_ERR, "Bad exports list line %s", line);
	if (ep && (ep->ex_flag & EX_LINKED) == 0)
		free_exp(ep);
	while (grp) {
		tgrp = grp;
		grp = grp->gr_next;
		free_grp(tgrp);
	}
}

/*
 * Search the export list for a matching fs.
 */
struct exportlist *
ex_search(fsid)
	fsid_t *fsid;
{
	struct exportlist *ep;

	ep = exphead;
	while (ep) {
		if (ep->ex_fs.val[0] == fsid->val[0] &&
		    ep->ex_fs.val[1] == fsid->val[1])
			return (ep);
		ep = ep->ex_next;
	}
	return (ep);
}

/*
 * Add a directory path to the list.
 */
char *
add_expdir(dpp, cp, len)
	struct dirlist **dpp;
	char *cp;
	int len;
{
	struct dirlist *dp;

	dp = (struct dirlist *)malloc(sizeof (struct dirlist) + len);
	dp->dp_left = *dpp;
	dp->dp_right = (struct dirlist *)NULL;
	dp->dp_flag = 0;
	dp->dp_hosts = (struct hostlist *)NULL;
	strcpy(dp->dp_dirp, cp);
	*dpp = dp;
	return (dp->dp_dirp);
}

/*
 * Hang the dir list element off the dirpath binary tree as required
 * and update the entry for host.
 */
void
hang_dirp(dp, grp, ep, alldirs)
	struct dirlist *dp;
	struct grouplist *grp;
	struct exportlist *ep;
	int alldirs;
{
	struct hostlist *hp;
	struct dirlist *dp2;

	if (alldirs) {
		if (ep->ex_defdir)
			free((caddr_t)dp);
		else
			ep->ex_defdir = dp;
		if (grp == (struct grouplist *)NULL)
			ep->ex_defdir->dp_flag |= DP_DEFSET;
		else while (grp) {
			hp = get_ht();
			hp->ht_grp = grp;
			hp->ht_next = ep->ex_defdir->dp_hosts;
			ep->ex_defdir->dp_hosts = hp;
			grp = grp->gr_next;
		}
	} else {

		/*
		 * Loop throught the directories adding them to the tree.
		 */
		while (dp) {
			dp2 = dp->dp_left;
			add_dlist(&ep->ex_dirl, dp, grp);
			dp = dp2;
		}
	}
}

/*
 * Traverse the binary tree either updating a node that is already there
 * for the new directory or adding the new node.
 */
void
add_dlist(dpp, newdp, grp)
	struct dirlist **dpp;
	struct dirlist *newdp;
	struct grouplist *grp;
{
	struct dirlist *dp;
	struct hostlist *hp;
	int cmp;

	dp = *dpp;
	if (dp) {
		cmp = strcmp(dp->dp_dirp, newdp->dp_dirp);
		if (cmp > 0) {
			add_dlist(&dp->dp_left, newdp, grp);
			return;
		} else if (cmp < 0) {
			add_dlist(&dp->dp_right, newdp, grp);
			return;
		} else
			free((caddr_t)newdp);
	} else {
		dp = newdp;
		dp->dp_left = (struct dirlist *)NULL;
		*dpp = dp;
	}
	if (grp) {

		/*
		 * Hang all of the host(s) off of the directory point.
		 */
		do {
			hp = get_ht();
			hp->ht_grp = grp;
			hp->ht_next = dp->dp_hosts;
			dp->dp_hosts = hp;
			grp = grp->gr_next;
		} while (grp);
	} else
		dp->dp_flag |= DP_DEFSET;
}

/*
 * Search for a dirpath on the export point.
 */
struct dirlist *
dirp_search(dp, dirpath)
	struct dirlist *dp;
	char *dirpath;
{
	int cmp;

	if (dp) {
		cmp = strcmp(dp->dp_dirp, dirpath);
		if (cmp > 0)
			return (dirp_search(dp->dp_left, dirpath));
		else if (cmp < 0)
			return (dirp_search(dp->dp_right, dirpath));
		else
			return (dp);
	}
	return (dp);
}

/*
 * Scan for a host match in a directory tree.
 */
int
chk_host(dp, saddr, defsetp)
	struct dirlist *dp;
	u_long saddr;
	int *defsetp;
{
	struct hostlist *hp;
	struct grouplist *grp;
	u_long **addrp;

	if (dp) {
		if (dp->dp_flag & DP_DEFSET)
			*defsetp = 1;
		hp = dp->dp_hosts;
		while (hp) {
			grp = hp->ht_grp;
			switch (grp->gr_type) {
			case GT_HOST:
			    addrp = (u_long **)
				grp->gr_ptr.gt_hostent->h_addr_list;
			    while (*addrp) {
				if (**addrp == saddr)
				    return (1);
				addrp++;
			    }
			    break;
			case GT_NET:
			    if ((saddr & grp->gr_ptr.gt_net.nt_mask) ==
				grp->gr_ptr.gt_net.nt_net)
				return (1);
			    break;
			};
			hp = hp->ht_next;
		}
	}
	return (0);
}

/*
 * Scan tree for a host that matches the address.
 */
int
scan_tree(dp, saddr)
	struct dirlist *dp;
	u_long saddr;
{
	int defset;

	if (dp) {
		if (scan_tree(dp->dp_left, saddr))
			return (1);
		if (chk_host(dp, saddr, &defset))
			return (1);
		if (scan_tree(dp->dp_right, saddr))
			return (1);
	}
	return (0);
}

/*
 * Traverse the dirlist tree and free it up.
 */
void
free_dir(dp)
	struct dirlist *dp;
{

	if (dp) {
		free_dir(dp->dp_left);
		free_dir(dp->dp_right);
		free_host(dp->dp_hosts);
		free((caddr_t)dp);
	}
}

/*
 * Parse the option string and update fields.
 * Option arguments may either be -<option>=<value> or
 * -<option> <value>
 */
int
do_opt(cpp, endcpp, ep, grp, has_hostp, exflagsp, cr)
	char **cpp, **endcpp;
	struct exportlist *ep;
	struct grouplist *grp;
	int *has_hostp;
	int *exflagsp;
	struct ucred *cr;
{
	char *cpoptarg, *cpoptend;
	char *cp, *endcp, *cpopt, savedc, savedc2;
	int allflag, usedarg;

	cpopt = *cpp;
	cpopt++;
	cp = *endcpp;
	savedc = *cp;
	*cp = '\0';
	while (cpopt && *cpopt) {
		allflag = 1;
		usedarg = -2;
		if (cpoptend = index(cpopt, ',')) {
			*cpoptend++ = '\0';
			if (cpoptarg = index(cpopt, '='))
				*cpoptarg++ = '\0';
		} else {
			if (cpoptarg = index(cpopt, '='))
				*cpoptarg++ = '\0';
			else {
				*cp = savedc;
				nextfield(&cp, &endcp);
				**endcpp = '\0';
				if (endcp > cp && *cp != '-') {
					cpoptarg = cp;
					savedc2 = *endcp;
					*endcp = '\0';
					usedarg = 0;
				}
			}
		}
		if (!strcmp(cpopt, "ro") || !strcmp(cpopt, "o")) {
			*exflagsp |= MNT_EXRDONLY;
		} else if (cpoptarg && (!strcmp(cpopt, "maproot") ||
		    !(allflag = strcmp(cpopt, "mapall")) ||
		    !strcmp(cpopt, "root") || !strcmp(cpopt, "r"))) {
			usedarg++;
			parsecred(cpoptarg, cr);
			if (allflag == 0) {
				*exflagsp |= MNT_EXPORTANON;
				opt_flags |= OP_MAPALL;
			} else
				opt_flags |= OP_MAPROOT;
		} else if (!strcmp(cpopt, "kerb") || !strcmp(cpopt, "k")) {
			*exflagsp |= MNT_EXKERB;
			opt_flags |= OP_KERB;
		} else if (cpoptarg && (!strcmp(cpopt, "mask") ||
			!strcmp(cpopt, "m"))) {
			if (get_net(cpoptarg, &grp->gr_ptr.gt_net, 1)) {
				syslog(LOG_ERR, "Bad mask: %s", cpoptarg);
				return (1);
			}
			usedarg++;
			opt_flags |= OP_MASK;
		} else if (cpoptarg && (!strcmp(cpopt, "network") ||
			!strcmp(cpopt, "n"))) {
			if (grp->gr_type != GT_NULL) {
				syslog(LOG_ERR, "Network/host conflict");
				return (1);
			} else if (get_net(cpoptarg, &grp->gr_ptr.gt_net, 0)) {
				syslog(LOG_ERR, "Bad net: %s", cpoptarg);
				return (1);
			}
			grp->gr_type = GT_NET;
			*has_hostp = 1;
			usedarg++;
			opt_flags |= OP_NET;
		} else if (!strcmp(cpopt, "alldirs")) {
			opt_flags |= OP_ALLDIRS;
#ifdef ISO
		} else if (cpoptarg && !strcmp(cpopt, "iso")) {
			if (get_isoaddr(cpoptarg, grp)) {
				syslog(LOG_ERR, "Bad iso addr: %s", cpoptarg);
				return (1);
			}
			*has_hostp = 1;
			usedarg++;
			opt_flags |= OP_ISO;
#endif /* ISO */
		} else {
			syslog(LOG_ERR, "Bad opt %s", cpopt);
			return (1);
		}
		if (usedarg >= 0) {
			*endcp = savedc2;
			**endcpp = savedc;
			if (usedarg > 0) {
				*cpp = cp;
				*endcpp = endcp;
			}
			return (0);
		}
		cpopt = cpoptend;
	}
	**endcpp = savedc;
	return (0);
}

/*
 * Translate a character string to the corresponding list of network
 * addresses for a hostname.
 */
int
get_host(cp, grp)
	char *cp;
	struct grouplist *grp;
{
	struct hostent *hp, *nhp;
	char **addrp, **naddrp;
	struct hostent t_host;
	int i;
	u_long saddr;
	char *aptr[2];

	if (grp->gr_type != GT_NULL)
		return (1);
	if ((hp = gethostbyname(cp)) == NULL) {
		if (isdigit(*cp)) {
			saddr = inet_addr(cp);
			if (saddr == -1) {
				syslog(LOG_ERR, "Inet_addr failed");
				return (1);
			}
			if ((hp = gethostbyaddr((caddr_t)&saddr, sizeof (saddr),
				AF_INET)) == NULL) {
				hp = &t_host;
				hp->h_name = cp;
				hp->h_addrtype = AF_INET;
				hp->h_length = sizeof (u_long);
				hp->h_addr_list = aptr;
				aptr[0] = (char *)&saddr;
				aptr[1] = (char *)NULL;
			}
		} else {
			syslog(LOG_ERR, "Gethostbyname failed");
			return (1);
		}
	}
	grp->gr_type = GT_HOST;
	nhp = grp->gr_ptr.gt_hostent = (struct hostent *)
		malloc(sizeof(struct hostent));
	if (nhp == (struct hostent *)NULL)
		out_of_mem();
	bcopy((caddr_t)hp, (caddr_t)nhp,
		sizeof(struct hostent));
	i = strlen(hp->h_name)+1;
	nhp->h_name = (char *)malloc(i);
	if (nhp->h_name == (char *)NULL)
		out_of_mem();
	bcopy(hp->h_name, nhp->h_name, i);
	addrp = hp->h_addr_list;
	i = 1;
	while (*addrp++)
		i++;
	naddrp = nhp->h_addr_list = (char **)
		malloc(i*sizeof(char *));
	if (naddrp == (char **)NULL)
		out_of_mem();
	addrp = hp->h_addr_list;
	while (*addrp) {
		*naddrp = (char *)
		    malloc(hp->h_length);
		if (*naddrp == (char *)NULL)
		    out_of_mem();
		bcopy(*addrp, *naddrp,
			hp->h_length);
		addrp++;
		naddrp++;