xref: /netbsd-src/lib/libperfuse/subr.c (revision ead2c0eee3abe6bcf08c63bfc78eb8a93a579b2b)
1 /*  $NetBSD: subr.c,v 1.15 2012/01/29 06:22:02 manu Exp $ */
2 
3 /*-
4  *  Copyright (c) 2010-2011 Emmanuel Dreyfus. All rights reserved.
5  *
6  *  Redistribution and use in source and binary forms, with or without
7  *  modification, are permitted provided that the following conditions
8  *  are met:
9  *  1. Redistributions of source code must retain the above copyright
10  *     notice, this list of conditions and the following disclaimer.
11  *  2. Redistributions in binary form must reproduce the above copyright
12  *     notice, this list of conditions and the following disclaimer in the
13  *     documentation and/or other materials provided with the distribution.
14  *
15  *  THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
16  *  ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
17  *  TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
18  *  PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
19  *  BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
20  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
21  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22  *  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23  *  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
24  *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25  *  POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <err.h>
31 #include <errno.h>
32 #include <sysexits.h>
33 #include <syslog.h>
34 #include <puffs.h>
35 #include <paths.h>
36 #include <sys/extattr.h>
37 
38 #include "perfuse_priv.h"
39 
40 struct perfuse_ns_map {
41 	const char *pnm_ns;
42 	const size_t pnm_nslen;
43 	const int pnm_native_ns;
44 };
45 
46 #define PERFUSE_NS_MAP(ns, native_ns)	\
47 	{ ns ".", sizeof(ns), native_ns }
48 
49 static size_t node_path(puffs_cookie_t, char *, size_t);
50 
51 struct puffs_node *
52 perfuse_new_pn(pu, name, parent)
53 	struct puffs_usermount *pu;
54 	const char *name;
55 	struct puffs_node *parent;
56 {
57 	struct puffs_node *pn;
58 	struct perfuse_node_data *pnd;
59 
60 	if ((pnd = malloc(sizeof(*pnd))) == NULL)
61 		DERR(EX_OSERR, "%s: malloc failed", __func__);
62 
63 	if ((pn = puffs_pn_new(pu, pnd)) == NULL)
64 		DERR(EX_SOFTWARE, "%s: puffs_pn_new failed", __func__);
65 
66 	(void)memset(pnd, 0, sizeof(*pnd));
67 	pnd->pnd_rfh = FUSE_UNKNOWN_FH;
68 	pnd->pnd_wfh = FUSE_UNKNOWN_FH;
69 	pnd->pnd_nodeid = PERFUSE_UNKNOWN_NODEID;
70 	pnd->pnd_nlookup = 1;
71 	pnd->pnd_parent = parent;
72 	pnd->pnd_pn = (puffs_cookie_t)pn;
73 	(void)strlcpy(pnd->pnd_name, name, MAXPATHLEN);
74 	TAILQ_INIT(&pnd->pnd_pcq);
75 	TAILQ_INIT(&pnd->pnd_children);
76 
77 	if (parent != NULL) {
78 		struct perfuse_node_data *parent_pnd;
79 
80 		parent_pnd = PERFUSE_NODE_DATA(parent);
81 		TAILQ_INSERT_TAIL(&parent_pnd->pnd_children, pnd, pnd_next);
82 
83 		parent_pnd->pnd_childcount++;
84 	}
85 
86 	return pn;
87 }
88 
89 void
90 perfuse_destroy_pn(pn)
91 	struct puffs_node *pn;
92 {
93 	struct perfuse_node_data *pnd;
94 
95 	pnd = PERFUSE_NODE_DATA(pn);
96 
97 	if (pnd->pnd_parent != NULL) {
98 		struct perfuse_node_data *parent_pnd;
99 
100 		parent_pnd = PERFUSE_NODE_DATA(pnd->pnd_parent);
101 		TAILQ_REMOVE(&parent_pnd->pnd_children, pnd, pnd_next);
102 	}
103 
104 	if ((pnd = puffs_pn_getpriv(pn)) != NULL) {
105 		if (pnd->pnd_parent != NULL)
106 			PERFUSE_NODE_DATA(pnd->pnd_parent)->pnd_childcount--;
107 
108 		if (pnd->pnd_dirent != NULL)
109 			free(pnd->pnd_dirent);
110 
111 		if (pnd->pnd_all_fd != NULL)
112 			free(pnd->pnd_all_fd);
113 #ifdef PERFUSE_DEBUG
114 		if (pnd->pnd_flags & PND_OPEN)
115 			DERRX(EX_SOFTWARE, "%s: file open", __func__);
116 
117 		if (!TAILQ_EMPTY(&pnd->pnd_pcq))
118 			DERRX(EX_SOFTWARE, "%s: non empty pnd_pcq", __func__);
119 
120 		if (pnd == NULL)
121 			DERRX(EX_SOFTWARE, "%s: pnd == NULL ???", __func__);
122 #endif /* PERFUSE_DEBUG */
123 
124 		free(pnd);
125 	}
126 
127 	puffs_pn_put(pn);
128 
129 	return;
130 }
131 
132 
133 void
134 perfuse_new_fh(opc, fh, mode)
135 	puffs_cookie_t opc;
136 	uint64_t fh;
137 	int mode;
138 {
139 	struct perfuse_node_data *pnd;
140 
141 	pnd = PERFUSE_NODE_DATA(opc);
142 
143 	if (mode & FWRITE) {
144 		if (pnd->pnd_flags & PND_WFH)
145 			DERRX(EX_SOFTWARE, "%s: opc = %p, write fh already set",
146 			      __func__, (void *)opc);
147 		pnd->pnd_wfh = fh;
148 		pnd->pnd_flags |= PND_WFH;
149 	}
150 
151 	if (mode & FREAD) {
152 		if (pnd->pnd_flags & PND_RFH)
153 			DERRX(EX_SOFTWARE, "%s: opc = %p, read fh already set",
154 			      __func__, (void *)opc);
155 		pnd->pnd_rfh = fh;
156 		pnd->pnd_flags |= PND_RFH;
157 	}
158 
159 	return;
160 }
161 
162 void
163 perfuse_destroy_fh(opc, fh)
164 	puffs_cookie_t opc;
165 	uint64_t fh;
166 {
167 	struct perfuse_node_data *pnd;
168 
169 	pnd = PERFUSE_NODE_DATA(opc);
170 
171 	if (fh == pnd->pnd_rfh) {
172 		if (!(pnd->pnd_flags & PND_RFH) && (fh != FUSE_UNKNOWN_FH))
173 			DERRX(EX_SOFTWARE,
174 			      "%s: opc = %p, unset rfh = %"PRIx64"",
175 			      __func__, (void *)opc, fh);
176 		pnd->pnd_rfh = FUSE_UNKNOWN_FH;
177 		pnd->pnd_flags &= ~PND_RFH;
178 	}
179 
180 	if (fh == pnd->pnd_wfh) {
181 		if (!(pnd->pnd_flags & PND_WFH) && (fh != FUSE_UNKNOWN_FH))
182 			DERRX(EX_SOFTWARE,
183 			      "%s: opc = %p, unset wfh = %"PRIx64"",
184 			      __func__, (void *)opc, fh);
185 		pnd->pnd_wfh = FUSE_UNKNOWN_FH;
186 		pnd->pnd_flags &= ~PND_WFH;
187 	}
188 
189 	return;
190 }
191 
192 uint64_t
193 perfuse_get_fh(opc, mode)
194 	puffs_cookie_t opc;
195 	int mode;
196 {
197 	struct perfuse_node_data *pnd;
198 
199 	pnd = PERFUSE_NODE_DATA(opc);
200 
201 	if (mode & FWRITE) {
202 		if (pnd->pnd_flags & PND_WFH)
203 			return pnd->pnd_wfh;
204 	}
205 
206 	if (mode & FREAD) {
207 		if (pnd->pnd_flags & PND_RFH)
208 			return pnd->pnd_rfh;
209 
210 		if (pnd->pnd_flags & PND_WFH)
211 			return pnd->pnd_wfh;
212 
213 	}
214 
215 	return FUSE_UNKNOWN_FH;
216 }
217 
218 static size_t
219 node_path(opc, buf, buflen)
220 	puffs_cookie_t opc;
221 	char *buf;
222 	size_t buflen;
223 {
224 	struct perfuse_node_data *pnd;
225 	size_t written;
226 
227 	pnd = PERFUSE_NODE_DATA(opc);
228 	if (pnd->pnd_parent == opc)
229 		return 0;
230 
231 	written = node_path(pnd->pnd_parent, buf, buflen);
232 	buf += written;
233 	buflen -= written;
234 
235 	return written + snprintf(buf, buflen, "/%s", pnd->pnd_name);
236 }
237 
238 char *
239 perfuse_node_path(opc)
240 	puffs_cookie_t opc;
241 {
242 	static char buf[MAXPATHLEN + 1];
243 
244 	if (node_path(opc, buf, sizeof(buf)) == 0)
245 		sprintf(buf, "/");
246 
247 	return buf;
248 }
249 
250 const char *
251 perfuse_native_ns(attrnamespace, attrname, fuse_attrname)
252 	const int attrnamespace;
253 	const char *attrname;
254 	char *fuse_attrname;
255 {
256 	const struct perfuse_ns_map *pnm;
257 	const struct perfuse_ns_map perfuse_ns_map[] = {
258 		PERFUSE_NS_MAP("trusted", EXTATTR_NAMESPACE_SYSTEM),
259 		PERFUSE_NS_MAP("security", EXTATTR_NAMESPACE_SYSTEM),
260 		PERFUSE_NS_MAP("system", EXTATTR_NAMESPACE_SYSTEM),
261 		PERFUSE_NS_MAP("user", EXTATTR_NAMESPACE_USER),
262 		{ NULL, 0, EXTATTR_NAMESPACE_USER },
263 	};
264 
265 	/*
266 	 * If attribute has a reserved Linux namespace (e.g.: trusted.foo)
267 	 * and that namespace matches the requested native namespace
268 	 * we have nothing to do.
269 	 * Otherwise we have either:
270 	 * (system|trusted|security).* with user namespace: prepend user.
271 	 * anything else with system napespace: prepend system.
272 	 */
273 	for (pnm = perfuse_ns_map; pnm->pnm_ns; pnm++) {
274 		if (strncmp(attrname, pnm->pnm_ns, pnm->pnm_nslen) != 0)
275 			continue;
276 
277 		if (attrnamespace == pnm->pnm_native_ns)
278 			return attrname;
279 
280 	 	/* (system|trusted|security).* with user namespace */
281 		if (attrnamespace == EXTATTR_NAMESPACE_USER) {
282 			(void)snprintf(fuse_attrname, LINUX_XATTR_NAME_MAX,
283 				       "user.%s", attrname);
284 			return (const char *)fuse_attrname;
285 		}
286 	}
287 
288 	/* anything else with system napespace */
289 	if (attrnamespace == EXTATTR_NAMESPACE_SYSTEM) {
290 		(void)snprintf(fuse_attrname, LINUX_XATTR_NAME_MAX,
291 			       "system.%s", attrname);
292 		return (const char *)fuse_attrname;
293 	}
294 
295 	return (const char *)attrname;
296 }
297