xref: /netbsd-src/lib/libperfuse/subr.c (revision c5e820cae412164fcbee52f470436200af5358ea)
1 /*  $NetBSD: subr.c,v 1.16 2012/03/08 14:58:57 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_fuse_nlookup = 1;
71 	pnd->pnd_puffs_nlookup = 1;
72 	pnd->pnd_parent = parent;
73 	pnd->pnd_pn = (puffs_cookie_t)pn;
74 	(void)strlcpy(pnd->pnd_name, name, MAXPATHLEN);
75 	TAILQ_INIT(&pnd->pnd_pcq);
76 	TAILQ_INIT(&pnd->pnd_children);
77 
78 	if (parent != NULL) {
79 		struct perfuse_node_data *parent_pnd;
80 
81 		parent_pnd = PERFUSE_NODE_DATA(parent);
82 		TAILQ_INSERT_TAIL(&parent_pnd->pnd_children, pnd, pnd_next);
83 
84 		parent_pnd->pnd_childcount++;
85 	}
86 
87 	return pn;
88 }
89 
90 void
91 perfuse_destroy_pn(pn)
92 	struct puffs_node *pn;
93 {
94 	struct perfuse_node_data *pnd;
95 
96 	pnd = PERFUSE_NODE_DATA(pn);
97 
98 	if (pnd->pnd_parent != NULL) {
99 		struct perfuse_node_data *parent_pnd;
100 
101 		parent_pnd = PERFUSE_NODE_DATA(pnd->pnd_parent);
102 		TAILQ_REMOVE(&parent_pnd->pnd_children, pnd, pnd_next);
103 	}
104 
105 	if ((pnd = puffs_pn_getpriv(pn)) != NULL) {
106 		if (pnd->pnd_parent != NULL)
107 			PERFUSE_NODE_DATA(pnd->pnd_parent)->pnd_childcount--;
108 
109 		if (pnd->pnd_dirent != NULL)
110 			free(pnd->pnd_dirent);
111 
112 		if (pnd->pnd_all_fd != NULL)
113 			free(pnd->pnd_all_fd);
114 #ifdef PERFUSE_DEBUG
115 		if (pnd->pnd_flags & PND_OPEN)
116 			DERRX(EX_SOFTWARE, "%s: file open", __func__);
117 
118 		if (!TAILQ_EMPTY(&pnd->pnd_pcq))
119 			DERRX(EX_SOFTWARE, "%s: non empty pnd_pcq", __func__);
120 
121 		if (pnd == NULL)
122 			DERRX(EX_SOFTWARE, "%s: pnd == NULL ???", __func__);
123 #endif /* PERFUSE_DEBUG */
124 
125 		free(pnd);
126 	}
127 
128 	puffs_pn_put(pn);
129 
130 	return;
131 }
132 
133 
134 void
135 perfuse_new_fh(opc, fh, mode)
136 	puffs_cookie_t opc;
137 	uint64_t fh;
138 	int mode;
139 {
140 	struct perfuse_node_data *pnd;
141 
142 	pnd = PERFUSE_NODE_DATA(opc);
143 
144 	if (mode & FWRITE) {
145 		if (pnd->pnd_flags & PND_WFH)
146 			DERRX(EX_SOFTWARE, "%s: opc = %p, write fh already set",
147 			      __func__, (void *)opc);
148 		pnd->pnd_wfh = fh;
149 		pnd->pnd_flags |= PND_WFH;
150 	}
151 
152 	if (mode & FREAD) {
153 		if (pnd->pnd_flags & PND_RFH)
154 			DERRX(EX_SOFTWARE, "%s: opc = %p, read fh already set",
155 			      __func__, (void *)opc);
156 		pnd->pnd_rfh = fh;
157 		pnd->pnd_flags |= PND_RFH;
158 	}
159 
160 	return;
161 }
162 
163 void
164 perfuse_destroy_fh(opc, fh)
165 	puffs_cookie_t opc;
166 	uint64_t fh;
167 {
168 	struct perfuse_node_data *pnd;
169 
170 	pnd = PERFUSE_NODE_DATA(opc);
171 
172 	if (fh == pnd->pnd_rfh) {
173 		if (!(pnd->pnd_flags & PND_RFH) && (fh != FUSE_UNKNOWN_FH))
174 			DERRX(EX_SOFTWARE,
175 			      "%s: opc = %p, unset rfh = %"PRIx64"",
176 			      __func__, (void *)opc, fh);
177 		pnd->pnd_rfh = FUSE_UNKNOWN_FH;
178 		pnd->pnd_flags &= ~PND_RFH;
179 	}
180 
181 	if (fh == pnd->pnd_wfh) {
182 		if (!(pnd->pnd_flags & PND_WFH) && (fh != FUSE_UNKNOWN_FH))
183 			DERRX(EX_SOFTWARE,
184 			      "%s: opc = %p, unset wfh = %"PRIx64"",
185 			      __func__, (void *)opc, fh);
186 		pnd->pnd_wfh = FUSE_UNKNOWN_FH;
187 		pnd->pnd_flags &= ~PND_WFH;
188 	}
189 
190 	return;
191 }
192 
193 uint64_t
194 perfuse_get_fh(opc, mode)
195 	puffs_cookie_t opc;
196 	int mode;
197 {
198 	struct perfuse_node_data *pnd;
199 
200 	pnd = PERFUSE_NODE_DATA(opc);
201 
202 	if (mode & FWRITE) {
203 		if (pnd->pnd_flags & PND_WFH)
204 			return pnd->pnd_wfh;
205 	}
206 
207 	if (mode & FREAD) {
208 		if (pnd->pnd_flags & PND_RFH)
209 			return pnd->pnd_rfh;
210 
211 		if (pnd->pnd_flags & PND_WFH)
212 			return pnd->pnd_wfh;
213 
214 	}
215 
216 	return FUSE_UNKNOWN_FH;
217 }
218 
219 static size_t
220 node_path(opc, buf, buflen)
221 	puffs_cookie_t opc;
222 	char *buf;
223 	size_t buflen;
224 {
225 	struct perfuse_node_data *pnd;
226 	size_t written;
227 
228 	pnd = PERFUSE_NODE_DATA(opc);
229 	if (pnd->pnd_parent == opc)
230 		return 0;
231 
232 	written = node_path(pnd->pnd_parent, buf, buflen);
233 	buf += written;
234 	buflen -= written;
235 
236 	return written + snprintf(buf, buflen, "/%s", pnd->pnd_name);
237 }
238 
239 char *
240 perfuse_node_path(opc)
241 	puffs_cookie_t opc;
242 {
243 	static char buf[MAXPATHLEN + 1];
244 
245 	if (node_path(opc, buf, sizeof(buf)) == 0)
246 		sprintf(buf, "/");
247 
248 	return buf;
249 }
250 
251 const char *
252 perfuse_native_ns(attrnamespace, attrname, fuse_attrname)
253 	const int attrnamespace;
254 	const char *attrname;
255 	char *fuse_attrname;
256 {
257 	const struct perfuse_ns_map *pnm;
258 	const struct perfuse_ns_map perfuse_ns_map[] = {
259 		PERFUSE_NS_MAP("trusted", EXTATTR_NAMESPACE_SYSTEM),
260 		PERFUSE_NS_MAP("security", EXTATTR_NAMESPACE_SYSTEM),
261 		PERFUSE_NS_MAP("system", EXTATTR_NAMESPACE_SYSTEM),
262 		PERFUSE_NS_MAP("user", EXTATTR_NAMESPACE_USER),
263 		{ NULL, 0, EXTATTR_NAMESPACE_USER },
264 	};
265 
266 	/*
267 	 * If attribute has a reserved Linux namespace (e.g.: trusted.foo)
268 	 * and that namespace matches the requested native namespace
269 	 * we have nothing to do.
270 	 * Otherwise we have either:
271 	 * (system|trusted|security).* with user namespace: prepend user.
272 	 * anything else with system napespace: prepend system.
273 	 */
274 	for (pnm = perfuse_ns_map; pnm->pnm_ns; pnm++) {
275 		if (strncmp(attrname, pnm->pnm_ns, pnm->pnm_nslen) != 0)
276 			continue;
277 
278 		if (attrnamespace == pnm->pnm_native_ns)
279 			return attrname;
280 
281 	 	/* (system|trusted|security).* with user namespace */
282 		if (attrnamespace == EXTATTR_NAMESPACE_USER) {
283 			(void)snprintf(fuse_attrname, LINUX_XATTR_NAME_MAX,
284 				       "user.%s", attrname);
285 			return (const char *)fuse_attrname;
286 		}
287 	}
288 
289 	/* anything else with system napespace */
290 	if (attrnamespace == EXTATTR_NAMESPACE_SYSTEM) {
291 		(void)snprintf(fuse_attrname, LINUX_XATTR_NAME_MAX,
292 			       "system.%s", attrname);
293 		return (const char *)fuse_attrname;
294 	}
295 
296 	return (const char *)attrname;
297 }
298