xref: /netbsd-src/lib/libperfuse/subr.c (revision 88fcb00c0357f2d7c1774f86a352637bfda96184)
1 /*  $NetBSD: subr.c,v 1.12 2011/06/28 16:19:16 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, "malloc failed");
62 
63 	if ((pn = puffs_pn_new(pu, pnd)) == NULL)
64 		DERR(EX_SOFTWARE, "puffs_pn_new failed");
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_ino = PERFUSE_UNKNOWN_INO;
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 #endif /* PERFUSE_DEBUG */
120 
121 		free(pnd);
122 	}
123 
124 	puffs_pn_put(pn);
125 
126 	return;
127 }
128 
129 
130 void
131 perfuse_new_fh(opc, fh, mode)
132 	puffs_cookie_t opc;
133 	uint64_t fh;
134 	int mode;
135 {
136 	struct perfuse_node_data *pnd;
137 
138 	pnd = PERFUSE_NODE_DATA(opc);
139 
140 	if (mode & FWRITE) {
141 		if (pnd->pnd_flags & PND_WFH)
142 			DERRX(EX_SOFTWARE, "%s: opc = %p, write fh already set",
143 			      __func__, (void *)opc);
144 		pnd->pnd_wfh = fh;
145 		pnd->pnd_flags |= PND_WFH;
146 	}
147 
148 	if (mode & FREAD) {
149 		if (pnd->pnd_flags & PND_RFH)
150 			DERRX(EX_SOFTWARE, "%s: opc = %p, read fh already set",
151 			      __func__, (void *)opc);
152 		pnd->pnd_rfh = fh;
153 		pnd->pnd_flags |= PND_RFH;
154 	}
155 
156 	return;
157 }
158 
159 void
160 perfuse_destroy_fh(opc, fh)
161 	puffs_cookie_t opc;
162 	uint64_t fh;
163 {
164 	struct perfuse_node_data *pnd;
165 
166 	pnd = PERFUSE_NODE_DATA(opc);
167 
168 	if (fh == pnd->pnd_rfh) {
169 		if (!(pnd->pnd_flags & PND_RFH) && (fh != FUSE_UNKNOWN_FH))
170 			DERRX(EX_SOFTWARE,
171 			      "%s: opc = %p, unset rfh = %"PRIx64"",
172 			      __func__, (void *)opc, fh);
173 		pnd->pnd_rfh = FUSE_UNKNOWN_FH;
174 		pnd->pnd_flags &= ~PND_RFH;
175 	}
176 
177 	if (fh == pnd->pnd_wfh) {
178 		if (!(pnd->pnd_flags & PND_WFH) && (fh != FUSE_UNKNOWN_FH))
179 			DERRX(EX_SOFTWARE,
180 			      "%s: opc = %p, unset wfh = %"PRIx64"",
181 			      __func__, (void *)opc, fh);
182 		pnd->pnd_wfh = FUSE_UNKNOWN_FH;
183 		pnd->pnd_flags &= ~PND_WFH;
184 	}
185 
186 	return;
187 }
188 
189 uint64_t
190 perfuse_get_fh(opc, mode)
191 	puffs_cookie_t opc;
192 	int mode;
193 {
194 	struct perfuse_node_data *pnd;
195 
196 	pnd = PERFUSE_NODE_DATA(opc);
197 
198 	if (mode & FWRITE) {
199 		if (pnd->pnd_flags & PND_WFH)
200 			return pnd->pnd_wfh;
201 	}
202 
203 	if (mode & FREAD) {
204 		if (pnd->pnd_flags & PND_RFH)
205 			return pnd->pnd_rfh;
206 
207 		if (pnd->pnd_flags & PND_WFH)
208 			return pnd->pnd_wfh;
209 
210 	}
211 
212 	return FUSE_UNKNOWN_FH;
213 }
214 
215 static size_t
216 node_path(opc, buf, buflen)
217 	puffs_cookie_t opc;
218 	char *buf;
219 	size_t buflen;
220 {
221 	struct perfuse_node_data *pnd;
222 	size_t written;
223 
224 	pnd = PERFUSE_NODE_DATA(opc);
225 	if (pnd->pnd_parent == opc)
226 		return 0;
227 
228 	written = node_path(pnd->pnd_parent, buf, buflen);
229 	buf += written;
230 	buflen -= written;
231 
232 	return written + snprintf(buf, buflen, "/%s", pnd->pnd_name);
233 }
234 
235 char *
236 perfuse_node_path(opc)
237 	puffs_cookie_t opc;
238 {
239 	static char buf[MAXPATHLEN + 1];
240 
241 	if (node_path(opc, buf, sizeof(buf)) == 0)
242 		sprintf(buf, "/");
243 
244 	return buf;
245 }
246 
247 const char *
248 perfuse_native_ns(attrnamespace, attrname, fuse_attrname)
249 	const int attrnamespace;
250 	const char *attrname;
251 	char *fuse_attrname;
252 {
253 	const struct perfuse_ns_map *pnm;
254 	const struct perfuse_ns_map perfuse_ns_map[] = {
255 		PERFUSE_NS_MAP("trusted", EXTATTR_NAMESPACE_SYSTEM),
256 		PERFUSE_NS_MAP("security", EXTATTR_NAMESPACE_SYSTEM),
257 		PERFUSE_NS_MAP("system", EXTATTR_NAMESPACE_SYSTEM),
258 		PERFUSE_NS_MAP("user", EXTATTR_NAMESPACE_USER),
259 		{ NULL, 0, EXTATTR_NAMESPACE_USER },
260 	};
261 
262 	/*
263 	 * If attribute has a reserved Linux namespace (e.g.: trusted.foo)
264 	 * and that namespace matches the requested native namespace
265 	 * we have nothing to do.
266 	 * Otherwise we have either:
267 	 * (system|trusted|security).* with user namespace: prepend user.
268 	 * anything else with system napespace: prepend system.
269 	 */
270 	for (pnm = perfuse_ns_map; pnm->pnm_ns; pnm++) {
271 		if (strncmp(attrname, pnm->pnm_ns, pnm->pnm_nslen) != 0)
272 			continue;
273 
274 		if (attrnamespace == pnm->pnm_native_ns)
275 			return attrname;
276 
277 	 	/* (system|trusted|security).* with user namespace */
278 		if (attrnamespace == EXTATTR_NAMESPACE_USER) {
279 			(void)snprintf(fuse_attrname, LINUX_XATTR_NAME_MAX,
280 				       "user.%s", attrname);
281 			return (const char *)fuse_attrname;
282 		}
283 	}
284 
285 	/* anything else with system napespace */
286 	if (attrnamespace == EXTATTR_NAMESPACE_SYSTEM) {
287 		(void)snprintf(fuse_attrname, LINUX_XATTR_NAME_MAX,
288 			       "system.%s", attrname);
289 		return (const char *)fuse_attrname;
290 	}
291 
292 	return (const char *)attrname;
293 }
294