xref: /illumos-gate/usr/src/lib/fm/libfmd_snmp/common/scheme.c (revision a07094369b21309434206d9b3601d162693466fc)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/fm/protocol.h>
30 #include <sys/types.h>
31 #include <sys/systeminfo.h>
32 #include <fm/fmd_snmp.h>
33 #include <net-snmp/net-snmp-config.h>
34 #include <net-snmp/net-snmp-includes.h>
35 #include <net-snmp/agent/net-snmp-agent-includes.h>
36 #include <libnvpair.h>
37 #include <limits.h>
38 #include <strings.h>
39 #include <stddef.h>
40 #include <unistd.h>
41 #include <dlfcn.h>
42 #include <errno.h>
43 
44 #define	SCHEMEDIR_BASE	"/usr/lib/fm/fmd/schemes"
45 
46 #if defined(__sparcv9)
47 #define	DEFAULTSCHEMEDIR	SCHEMEDIR_BASE "/sparcv9"
48 #elif defined(__amd64)
49 #define	DEFAULTSCHEMEDIR	SCHEMEDIR_BASE "/amd64"
50 #else
51 #define	DEFAULTSCHEMEDIR	SCHEMEDIR_BASE
52 #endif
53 
54 typedef struct fmd_scheme_ops {
55 	int (*sop_init)(void);
56 	void (*sop_fini)(void);
57 	ssize_t (*sop_nvl2str)(nvlist_t *, char *, size_t);
58 } fmd_scheme_ops_t;
59 
60 typedef struct fmd_scheme_opd {
61 	const char *opd_name;		/* symbol name of scheme function */
62 	size_t opd_off;			/* offset within fmd_scheme_ops_t */
63 } fmd_scheme_opd_t;
64 
65 typedef struct fmd_scheme {
66 	struct fmd_scheme *sch_next;    /* next scheme on list of schemes */
67 	char *sch_name;			/* name of this scheme (fmri prefix) */
68 	void *sch_dlp;			/* libdl(3DL) shared library handle */
69 	int sch_err;			/* if negative entry, errno to return */
70 	fmd_scheme_ops_t sch_ops;	/* scheme function pointers */
71 } fmd_scheme_t;
72 
73 static fmd_scheme_t *sch_list;		/* list of cached schemes */
74 static char *g_root;			/* fmd root dir */
75 
76 static long
77 fmd_scheme_notsup(void)
78 {
79 	errno = ENOTSUP;
80 	return (-1);
81 }
82 
83 static int
84 fmd_scheme_nop(void)
85 {
86 	return (0);
87 }
88 
89 /*
90  * Default values for the scheme ops.  If a scheme function is not defined in
91  * the module, then this operation is implemented using the default function.
92  */
93 static const fmd_scheme_ops_t _fmd_scheme_default_ops = {
94 	(int (*)())fmd_scheme_nop,		/* sop_init */
95 	(void (*)())fmd_scheme_nop,		/* sop_fini */
96 	(ssize_t (*)())fmd_scheme_notsup,	/* sop_nvl2str */
97 };
98 
99 /*
100  * Scheme ops descriptions.  These names and offsets are used by the function
101  * fmd_scheme_rtld_init(), defined below, to load up a fmd_scheme_ops_t.
102  */
103 static const fmd_scheme_opd_t _fmd_scheme_ops[] = {
104 	{ "fmd_fmri_init", offsetof(fmd_scheme_ops_t, sop_init) },
105 	{ "fmd_fmri_fini", offsetof(fmd_scheme_ops_t, sop_fini) },
106 	{ "fmd_fmri_nvl2str", offsetof(fmd_scheme_ops_t, sop_nvl2str) },
107 	{ NULL, 0 }
108 };
109 
110 static fmd_scheme_t *
111 fmd_scheme_create(const char *name)
112 {
113 	fmd_scheme_t *sp;
114 
115 	if ((sp = malloc(sizeof (fmd_scheme_t))) == NULL ||
116 	    (sp->sch_name = strdup(name)) == NULL) {
117 		free(sp);
118 		return (NULL);
119 	}
120 
121 	sp->sch_next = sch_list;
122 	sp->sch_dlp = NULL;
123 	sp->sch_err = 0;
124 	sp->sch_ops = _fmd_scheme_default_ops;
125 
126 	sch_list = sp;
127 	return (sp);
128 }
129 
130 static int
131 fmd_scheme_rtld_init(fmd_scheme_t *sp)
132 {
133 	const fmd_scheme_opd_t *opd;
134 	void *p;
135 
136 	for (opd = _fmd_scheme_ops; opd->opd_name != NULL; opd++) {
137 		if ((p = dlsym(sp->sch_dlp, opd->opd_name)) != NULL)
138 			*(void **)((uintptr_t)&sp->sch_ops + opd->opd_off) = p;
139 	}
140 
141 	return (sp->sch_ops.sop_init());
142 }
143 
144 static fmd_scheme_t *
145 fmd_scheme_lookup(const char *dir, const char *name)
146 {
147 	fmd_scheme_t *sp;
148 	char path[PATH_MAX];
149 
150 	for (sp = sch_list; sp != NULL; sp = sp->sch_next) {
151 		if (strcmp(name, sp->sch_name) == 0)
152 			return (sp);
153 	}
154 
155 	if ((sp = fmd_scheme_create(name)) == NULL)
156 		return (NULL); /* errno is set for us */
157 
158 	(void) snprintf(path, sizeof (path), "%s%s/%s.so",
159 	    g_root ? g_root : "", dir, name);
160 
161 	if (access(path, F_OK) != 0) {
162 		sp->sch_err = errno;
163 		return (sp);
164 	}
165 
166 	if ((sp->sch_dlp = dlopen(path, RTLD_LOCAL | RTLD_NOW | RTLD_PARENT)) ==
167 	    NULL) {
168 		sp->sch_err = ELIBACC;
169 		return (sp);
170 	}
171 
172 	if (fmd_scheme_rtld_init(sp) != 0) {
173 		sp->sch_err = errno;
174 		(void) dlclose(sp->sch_dlp);
175 		sp->sch_dlp = NULL;
176 	}
177 
178 	return (sp);
179 }
180 
181 char *
182 sunFm_nvl2str(nvlist_t *nvl)
183 {
184 	fmd_scheme_t *sp;
185 	char c, *name, *s = NULL;
186 	ssize_t len;
187 
188 	if (nvlist_lookup_string(nvl, FM_FMRI_SCHEME, &name) != 0) {
189 		DEBUGMSGTL((MODNAME_STR, "fmri does not contain required "
190 		    "'%s' nvpair\n", FM_FMRI_SCHEME));
191 		return (NULL);
192 	}
193 
194 	if ((sp = fmd_scheme_lookup(DEFAULTSCHEMEDIR, name)) == NULL ||
195 	    sp->sch_dlp == NULL || sp->sch_err != 0) {
196 		const char *msg =
197 		    sp->sch_err == ELIBACC ? dlerror() : strerror(sp->sch_err);
198 		DEBUGMSGTL((MODNAME_STR, "cannot init '%s' scheme library to "
199 		    "format fmri: %s\n", name, msg ? msg : "unknown error"));
200 		return (NULL);
201 	}
202 
203 	if ((len = sp->sch_ops.sop_nvl2str(nvl, &c, sizeof (c))) == -1 ||
204 	    (s = malloc(len + 1)) == NULL ||
205 	    sp->sch_ops.sop_nvl2str(nvl, s, len + 1) == -1) {
206 		DEBUGMSGTL((MODNAME_STR, "cannot format fmri using scheme '%s'",
207 		    name));
208 		free(s);
209 		return (NULL);
210 	}
211 
212 	return (s);
213 }
214 
215 void *
216 fmd_fmri_alloc(size_t size)
217 {
218 	return (malloc(size));
219 }
220 
221 void *
222 fmd_fmri_zalloc(size_t size)
223 {
224 	void *data;
225 
226 	if ((data = malloc(size)) != NULL)
227 		bzero(data, size);
228 
229 	return (data);
230 }
231 
232 /*ARGSUSED*/
233 void
234 fmd_fmri_free(void *data, size_t size)
235 {
236 	free(data);
237 }
238 
239 int
240 fmd_fmri_error(int err)
241 {
242 	errno = err;
243 	return (-1);
244 }
245 
246 char *
247 fmd_fmri_strescape(const char *s)
248 {
249 	return (strdup(s));
250 }
251 
252 char *
253 fmd_fmri_strdup(const char *s)
254 {
255 	return (strdup(s));
256 }
257 
258 void
259 fmd_fmri_strfree(char *s)
260 {
261 	free(s);
262 }
263 
264 const char *
265 fmd_fmri_get_rootdir(void)
266 {
267 	return (g_root ? g_root : "");
268 }
269 
270 const char *
271 fmd_fmri_get_platform(void)
272 {
273 	static char platform[MAXNAMELEN];
274 
275 	if (platform[0] == '\0')
276 		(void) sysinfo(SI_PLATFORM, platform, sizeof (platform));
277 
278 	return (platform);
279 }
280 
281 uint64_t
282 fmd_fmri_get_drgen(void)
283 {
284 	return (0);
285 }
286 
287 int
288 fmd_fmri_set_errno(int err)
289 {
290 	errno = err;
291 	return (-1);
292 }
293 
294 void
295 fmd_fmri_warn(const char *format, ...)
296 {
297 }
298