xref: /netbsd-src/lib/libperfuse/subr.c (revision ac7134332d74254110ff169261cae2e58eb02efd)
1 /*  $NetBSD: subr.c,v 1.20 2014/08/10 03:22:33 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/hash.h>
37 #include <sys/extattr.h>
38 
39 #include "perfuse_priv.h"
40 
41 struct perfuse_ns_map {
42 	const char *pnm_ns;
43 	const size_t pnm_nslen;
44 	const int pnm_native_ns;
45 };
46 
47 #define PERFUSE_NS_MAP(ns, native_ns)	\
48 	{ ns ".", sizeof(ns), native_ns }
49 
50 static __inline struct perfuse_node_hashlist *perfuse_nidhash(struct
51     perfuse_state *, uint64_t);
52 
53 struct puffs_node *
perfuse_new_pn(struct puffs_usermount * pu,const char * name,struct puffs_node * parent)54 perfuse_new_pn(struct puffs_usermount *pu, const char *name,
55 	struct puffs_node *parent)
56 {
57 	struct perfuse_state *ps = puffs_getspecific(pu);
58 	struct puffs_node *pn;
59 	struct perfuse_node_data *pnd;
60 
61 	if ((pnd = malloc(sizeof(*pnd))) == NULL)
62 		DERR(EX_OSERR, "%s: malloc failed", __func__);
63 
64 	if ((pn = puffs_pn_new(pu, pnd)) == NULL)
65 		DERR(EX_SOFTWARE, "%s: puffs_pn_new failed", __func__);
66 
67 	(void)memset(pnd, 0, sizeof(*pnd));
68 	pnd->pnd_rfh = FUSE_UNKNOWN_FH;
69 	pnd->pnd_wfh = FUSE_UNKNOWN_FH;
70 	pnd->pnd_nodeid = PERFUSE_UNKNOWN_NODEID;
71 	if (parent != NULL) {
72 		pnd->pnd_parent_nodeid = PERFUSE_NODE_DATA(parent)->pnd_nodeid;
73 	} else {
74 		pnd->pnd_parent_nodeid = FUSE_ROOT_ID;
75 	}
76 	pnd->pnd_fuse_nlookup = 0;
77 	pnd->pnd_puffs_nlookup = 0;
78 	pnd->pnd_pn = (puffs_cookie_t)pn;
79 	if (strcmp(name, "..") != 0)
80 		(void)strlcpy(pnd->pnd_name, name, MAXPATHLEN);
81 	else
82 		pnd->pnd_name[0] = 0; /* anonymous for now */
83 	TAILQ_INIT(&pnd->pnd_pcq);
84 
85 	puffs_pn_setpriv(pn, pnd);
86 
87 	ps->ps_nodecount++;
88 
89 	return pn;
90 }
91 
92 void
perfuse_destroy_pn(struct puffs_usermount * pu,struct puffs_node * pn)93 perfuse_destroy_pn(struct puffs_usermount *pu, struct puffs_node *pn)
94 {
95 	struct perfuse_state *ps = puffs_getspecific(pu);
96 	struct perfuse_node_data *pnd;
97 
98 	if ((pnd = puffs_pn_getpriv(pn)) != NULL) {
99 		if (pnd->pnd_all_fd != NULL)
100 			free(pnd->pnd_all_fd);
101 
102 		if (pnd->pnd_dirent != NULL)
103 			free(pnd->pnd_dirent);
104 
105 #ifdef PERFUSE_DEBUG
106 		if (pnd->pnd_flags & PND_OPEN)
107 			DERRX(EX_SOFTWARE, "%s: file open", __func__);
108 
109 		if (!TAILQ_EMPTY(&pnd->pnd_pcq))
110 			DERRX(EX_SOFTWARE, "%s: non empty pnd_pcq", __func__);
111 
112 		pnd->pnd_flags |= PND_INVALID;
113 #endif /* PERFUSE_DEBUG */
114 
115 		free(pnd);
116 	}
117 
118 	puffs_pn_put(pn);
119 
120 	ps->ps_nodecount--;
121 
122 	return;
123 }
124 
125 void
perfuse_new_fh(puffs_cookie_t opc,uint64_t fh,int mode)126 perfuse_new_fh(puffs_cookie_t opc, uint64_t fh, int mode)
127 {
128 	struct perfuse_node_data *pnd;
129 
130 	pnd = PERFUSE_NODE_DATA(opc);
131 
132 	if (mode & FWRITE) {
133 		if (pnd->pnd_flags & PND_WFH)
134 			DERRX(EX_SOFTWARE, "%s: opc = %p, write fh already set",
135 			      __func__, (void *)opc);
136 		pnd->pnd_wfh = fh;
137 		pnd->pnd_flags |= PND_WFH;
138 	}
139 
140 	if (mode & FREAD) {
141 		if (pnd->pnd_flags & PND_RFH)
142 			DERRX(EX_SOFTWARE, "%s: opc = %p, read fh already set",
143 			      __func__, (void *)opc);
144 		pnd->pnd_rfh = fh;
145 		pnd->pnd_flags |= PND_RFH;
146 	}
147 
148 	return;
149 }
150 
151 void
perfuse_destroy_fh(puffs_cookie_t opc,uint64_t fh)152 perfuse_destroy_fh(puffs_cookie_t opc, uint64_t fh)
153 {
154 	struct perfuse_node_data *pnd;
155 
156 	pnd = PERFUSE_NODE_DATA(opc);
157 
158 	if (fh == pnd->pnd_rfh) {
159 		if (!(pnd->pnd_flags & PND_RFH) && (fh != FUSE_UNKNOWN_FH))
160 			DERRX(EX_SOFTWARE,
161 			      "%s: opc = %p, unset rfh = %"PRIx64"",
162 			      __func__, (void *)opc, fh);
163 		pnd->pnd_rfh = FUSE_UNKNOWN_FH;
164 		pnd->pnd_flags &= ~PND_RFH;
165 	}
166 
167 	if (fh == pnd->pnd_wfh) {
168 		if (!(pnd->pnd_flags & PND_WFH) && (fh != FUSE_UNKNOWN_FH))
169 			DERRX(EX_SOFTWARE,
170 			      "%s: opc = %p, unset wfh = %"PRIx64"",
171 			      __func__, (void *)opc, fh);
172 		pnd->pnd_wfh = FUSE_UNKNOWN_FH;
173 		pnd->pnd_flags &= ~PND_WFH;
174 	}
175 
176 	return;
177 }
178 
179 uint64_t
perfuse_get_fh(puffs_cookie_t opc,int mode)180 perfuse_get_fh(puffs_cookie_t opc, int mode)
181 {
182 	struct perfuse_node_data *pnd;
183 
184 	pnd = PERFUSE_NODE_DATA(opc);
185 
186 	if (mode & FWRITE) {
187 		if (pnd->pnd_flags & PND_WFH)
188 			return pnd->pnd_wfh;
189 	}
190 
191 	if (mode & FREAD) {
192 		if (pnd->pnd_flags & PND_RFH)
193 			return pnd->pnd_rfh;
194 
195 		if (pnd->pnd_flags & PND_WFH)
196 			return pnd->pnd_wfh;
197 
198 	}
199 
200 	return FUSE_UNKNOWN_FH;
201 }
202 
203 /* ARGSUSED0 */
204 char *
perfuse_node_path(struct perfuse_state * ps,puffs_cookie_t opc)205 perfuse_node_path(struct perfuse_state *ps, puffs_cookie_t opc)
206 {
207 	static char buf[MAXPATHLEN + 1];
208 
209 #if 0
210 	if (node_path(ps, opc, buf, sizeof(buf)) == 0)
211 		sprintf(buf, "/");
212 #endif
213 	sprintf(buf, "%s", PERFUSE_NODE_DATA(opc)->pnd_name);
214 
215 	return buf;
216 }
217 
218 int
perfuse_ns_match(const int attrnamespace,const char * attrname)219 perfuse_ns_match(const int attrnamespace, const char *attrname)
220 {
221 	const char *system_ns[] = { "system.", "trusted.", "security", NULL };
222 	int i;
223 
224         for (i = 0; system_ns[i]; i++) {
225                 if (strncmp(attrname, system_ns[i], strlen(system_ns[i])) == 0)
226 			return (attrnamespace == EXTATTR_NAMESPACE_SYSTEM);
227         }
228 
229 	return (attrnamespace == EXTATTR_NAMESPACE_USER);
230 }
231 
232 const char *
perfuse_native_ns(const int attrnamespace,const char * attrname,char * fuse_attrname)233 perfuse_native_ns(const int attrnamespace, const char *attrname,
234 	char *fuse_attrname)
235 {
236 	const struct perfuse_ns_map *pnm;
237 	const struct perfuse_ns_map perfuse_ns_map[] = {
238 		PERFUSE_NS_MAP("trusted", EXTATTR_NAMESPACE_SYSTEM),
239 		PERFUSE_NS_MAP("security", EXTATTR_NAMESPACE_SYSTEM),
240 		PERFUSE_NS_MAP("system", EXTATTR_NAMESPACE_SYSTEM),
241 		PERFUSE_NS_MAP("user", EXTATTR_NAMESPACE_USER),
242 		{ NULL, 0, EXTATTR_NAMESPACE_USER },
243 	};
244 
245 	/*
246 	 * If attribute has a reserved Linux namespace (e.g.: trusted.foo)
247 	 * and that namespace matches the requested native namespace
248 	 * we have nothing to do.
249 	 * Otherwise we have either:
250 	 * (system|trusted|security).* with user namespace: prepend user.
251 	 * anything else with system napespace: prepend system.
252 	 */
253 	for (pnm = perfuse_ns_map; pnm->pnm_ns; pnm++) {
254 		if (strncmp(attrname, pnm->pnm_ns, pnm->pnm_nslen) != 0)
255 			continue;
256 
257 		if (attrnamespace == pnm->pnm_native_ns)
258 			return attrname;
259 
260 	 	/* (system|trusted|security).* with user namespace */
261 		if (attrnamespace == EXTATTR_NAMESPACE_USER) {
262 			(void)snprintf(fuse_attrname, LINUX_XATTR_NAME_MAX,
263 				       "user.%s", attrname);
264 			return (const char *)fuse_attrname;
265 		}
266 	}
267 
268 	/* anything else with system napespace */
269 	if (attrnamespace == EXTATTR_NAMESPACE_SYSTEM) {
270 		(void)snprintf(fuse_attrname, LINUX_XATTR_NAME_MAX,
271 			       "system.%s", attrname);
272 		return (const char *)fuse_attrname;
273 	}
274 
275 	return (const char *)attrname;
276 }
277 
278 static __inline struct perfuse_node_hashlist *
perfuse_nidhash(struct perfuse_state * ps,uint64_t nodeid)279 perfuse_nidhash(struct perfuse_state *ps, uint64_t nodeid)
280 {
281         uint32_t hash;
282 
283         hash = hash32_buf(&nodeid, sizeof(nodeid), HASH32_BUF_INIT);
284 
285 	return &ps->ps_nidhash[hash % ps->ps_nnidhash];
286 }
287 
288 struct perfuse_node_data *
perfuse_node_bynodeid(struct perfuse_state * ps,uint64_t nodeid)289 perfuse_node_bynodeid(struct perfuse_state *ps, uint64_t nodeid)
290 {
291 	struct perfuse_node_hashlist *plist;
292 	struct perfuse_node_data *pnd;
293 
294 	plist = perfuse_nidhash(ps, nodeid);
295 
296 	LIST_FOREACH(pnd, plist, pnd_nident)
297 		if (pnd->pnd_nodeid == nodeid)
298 			break;
299 
300 	return pnd;
301 }
302 
303 void
perfuse_node_cache(struct perfuse_state * ps,puffs_cookie_t opc)304 perfuse_node_cache(struct perfuse_state *ps, puffs_cookie_t opc)
305 {
306 	struct perfuse_node_data *pnd = PERFUSE_NODE_DATA(opc);
307 	struct perfuse_node_hashlist *nidlist;
308 
309 	if (pnd->pnd_flags & PND_REMOVED)
310 		DERRX(EX_SOFTWARE, "%s: \"%s\" already removed",
311 		      __func__, pnd->pnd_name);
312 
313 	nidlist = perfuse_nidhash(ps, pnd->pnd_nodeid);
314 	LIST_INSERT_HEAD(nidlist, pnd, pnd_nident);
315 
316 	return;
317 }
318 
319 void
perfuse_cache_flush(puffs_cookie_t opc)320 perfuse_cache_flush(puffs_cookie_t opc)
321 {
322 	struct perfuse_node_data *pnd = PERFUSE_NODE_DATA(opc);
323 
324 	if (pnd->pnd_flags & PND_REMOVED)
325 		DERRX(EX_SOFTWARE, "%s: \"%s\" already removed",
326 		      __func__, pnd->pnd_name);
327 
328 	LIST_REMOVE(pnd, pnd_nident);
329 
330 	return;
331 }
332