xref: /illumos-gate/usr/src/lib/libproc/common/Pidle.c (revision 67a4bb8f9ad4c49e9aa9e21e2114a7c093c3a73a)
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  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 /*
26  * Copyright (c) 2013 by Delphix. All rights reserved.
27  */
28 
29 #include <stdlib.h>
30 #include <libelf.h>
31 #include <libgen.h>
32 #include <string.h>
33 #include <strings.h>
34 #include <errno.h>
35 #include <sys/sysmacros.h>
36 
37 #include "libproc.h"
38 #include "Pcontrol.h"
39 
40 /*ARGSUSED*/
41 static ssize_t
42 Pread_idle(struct ps_prochandle *P, void *buf, size_t n, uintptr_t addr,
43     void *data)
44 {
45 	size_t resid = n;
46 
47 	while (resid > 0) {
48 		map_info_t *mp;
49 		uintptr_t mapoff;
50 		ssize_t len;
51 		off64_t off;
52 
53 		if ((mp = Paddr2mptr(P, addr)) == NULL)
54 			break;
55 
56 		mapoff = addr - mp->map_pmap.pr_vaddr;
57 		len = MIN(resid, mp->map_pmap.pr_size - mapoff);
58 		off = mp->map_offset + mapoff;
59 
60 		if ((len = pread64(P->asfd, buf, len, off)) <= 0)
61 			break;
62 
63 		resid -= len;
64 		addr += len;
65 		buf = (char *)buf + len;
66 	}
67 
68 	return (n - resid);
69 }
70 
71 /*ARGSUSED*/
72 static ssize_t
73 Pwrite_idle(struct ps_prochandle *P, const void *buf, size_t n, uintptr_t addr,
74     void *data)
75 {
76 	errno = EIO;
77 	return (-1);
78 }
79 
80 /*ARGSUSED*/
81 static int
82 Ppriv_idle(struct ps_prochandle *P, prpriv_t **pprv, void *data)
83 {
84 	prpriv_t *pp;
85 
86 	pp = proc_get_priv(P->pid);
87 	if (pp == NULL) {
88 		return (-1);
89 	}
90 
91 	*pprv = pp;
92 	return (0);
93 }
94 
95 /* Default operations for the idl ops vector. */
96 static void *
97 Pidle_voidp()
98 {
99 	errno = ENODATA;
100 	return (NULL);
101 }
102 
103 static int
104 Pidle_int()
105 {
106 	errno = ENODATA;
107 	return (-1);
108 }
109 
110 static const ps_ops_t P_idle_ops = {
111 	.pop_pread	= Pread_idle,
112 	.pop_pwrite	= Pwrite_idle,
113 	.pop_cred	= (pop_cred_t)Pidle_int,
114 	.pop_priv	= Ppriv_idle,
115 	.pop_psinfo	= (pop_psinfo_t)Pidle_voidp,
116 	.pop_platform	= (pop_platform_t)Pidle_voidp,
117 	.pop_uname	= (pop_uname_t)Pidle_int,
118 	.pop_zonename	= (pop_zonename_t)Pidle_voidp,
119 #if defined(__i386) || defined(__amd64)
120 	.pop_ldt	= (pop_ldt_t)Pidle_int
121 #endif
122 };
123 
124 static int
125 idle_add_mapping(struct ps_prochandle *P, GElf_Phdr *php, file_info_t *fp)
126 {
127 	prmap_t pmap;
128 
129 	dprintf("mapping base %llx filesz %llu memsz %llu offset %llu\n",
130 	    (u_longlong_t)php->p_vaddr, (u_longlong_t)php->p_filesz,
131 	    (u_longlong_t)php->p_memsz, (u_longlong_t)php->p_offset);
132 
133 	pmap.pr_vaddr = (uintptr_t)php->p_vaddr;
134 	pmap.pr_size = php->p_filesz;
135 	(void) strncpy(pmap.pr_mapname, fp->file_pname,
136 	    sizeof (pmap.pr_mapname));
137 	pmap.pr_offset = php->p_offset;
138 
139 	pmap.pr_mflags = 0;
140 	if (php->p_flags & PF_R)
141 		pmap.pr_mflags |= MA_READ;
142 	if (php->p_flags & PF_W)
143 		pmap.pr_mflags |= MA_WRITE;
144 	if (php->p_flags & PF_X)
145 		pmap.pr_mflags |= MA_EXEC;
146 
147 	pmap.pr_pagesize = 0;
148 	pmap.pr_shmid = -1;
149 
150 	return (Padd_mapping(P, php->p_offset, fp, &pmap));
151 }
152 
153 struct ps_prochandle *
154 Pgrab_file(const char *fname, int *perr)
155 {
156 	struct ps_prochandle *P = NULL;
157 	char buf[PATH_MAX];
158 	GElf_Ehdr ehdr;
159 	Elf *elf = NULL;
160 	size_t phnum;
161 	file_info_t *fp = NULL;
162 	int fd;
163 	int i;
164 
165 	if ((fd = open64(fname, O_RDONLY)) < 0) {
166 		dprintf("couldn't open file");
167 		*perr = (errno == ENOENT) ? G_NOEXEC : G_STRANGE;
168 		return (NULL);
169 	}
170 
171 	if (elf_version(EV_CURRENT) == EV_NONE) {
172 		dprintf("libproc ELF version is more recent than libelf");
173 		*perr = G_ELF;
174 		goto err;
175 	}
176 
177 	if ((P = calloc(1, sizeof (struct ps_prochandle))) == NULL) {
178 		*perr = G_STRANGE;
179 		goto err;
180 	}
181 
182 	(void) mutex_init(&P->proc_lock, USYNC_THREAD, NULL);
183 	P->state = PS_IDLE;
184 	P->pid = (pid_t)-1;
185 	P->asfd = fd;
186 	P->ctlfd = -1;
187 	P->statfd = -1;
188 	P->agentctlfd = -1;
189 	P->agentstatfd = -1;
190 	P->info_valid = -1;
191 	Pinit_ops(&P->ops, &P_idle_ops);
192 	Pinitsym(P);
193 
194 	if ((elf = elf_begin(fd, ELF_C_READ, NULL)) == NULL) {
195 		*perr = G_ELF;
196 		return (NULL);
197 	}
198 
199 	/*
200 	 * Construct a file_info_t that corresponds to this file.
201 	 */
202 	if ((fp = calloc(1, sizeof (file_info_t))) == NULL) {
203 		*perr = G_STRANGE;
204 		goto err;
205 	}
206 
207 	if ((fp->file_lo = calloc(1, sizeof (rd_loadobj_t))) == NULL) {
208 		*perr = G_STRANGE;
209 		goto err;
210 	}
211 
212 	if (*fname == '/') {
213 		(void) strncpy(fp->file_pname, fname, sizeof (fp->file_pname));
214 	} else {
215 		size_t sz;
216 
217 		if (getcwd(fp->file_pname, sizeof (fp->file_pname) - 1) ==
218 		    NULL) {
219 			*perr = G_STRANGE;
220 			goto err;
221 		}
222 
223 		sz = strlen(fp->file_pname);
224 		(void) snprintf(&fp->file_pname[sz],
225 		    sizeof (fp->file_pname) - sz, "/%s", fname);
226 	}
227 
228 	fp->file_fd = fd;
229 	fp->file_lo->rl_lmident = LM_ID_BASE;
230 	if ((fp->file_lname = strdup(fp->file_pname)) == NULL) {
231 		*perr = G_STRANGE;
232 		goto err;
233 	}
234 	fp->file_lbase = basename(fp->file_lname);
235 
236 	if ((P->execname = strdup(fp->file_pname)) == NULL) {
237 		*perr = G_STRANGE;
238 		goto err;
239 	}
240 
241 	P->num_files++;
242 	list_link(fp, &P->file_head);
243 
244 	if (gelf_getehdr(elf, &ehdr) == NULL) {
245 		*perr = G_STRANGE;
246 		goto err;
247 	}
248 
249 	if (elf_getphdrnum(elf, &phnum) == -1) {
250 		*perr = G_STRANGE;
251 		goto err;
252 	}
253 
254 	dprintf("Pgrab_file: program header count = %lu\n", (ulong_t)phnum);
255 
256 	/*
257 	 * Sift through the program headers making the relevant maps.
258 	 */
259 	for (i = 0; i < phnum; i++) {
260 		GElf_Phdr phdr, *php;
261 
262 		if ((php = gelf_getphdr(elf, i, &phdr)) == NULL) {
263 			*perr = G_STRANGE;
264 			goto err;
265 		}
266 
267 		if (php->p_type != PT_LOAD)
268 			continue;
269 
270 		if (idle_add_mapping(P, php, fp) != 0) {
271 			*perr = G_STRANGE;
272 			goto err;
273 		}
274 	}
275 	Psort_mappings(P);
276 
277 	(void) elf_end(elf);
278 
279 	P->map_exec = fp->file_map;
280 
281 	P->status.pr_flags = PR_STOPPED;
282 	P->status.pr_nlwp = 0;
283 	P->status.pr_pid = (pid_t)-1;
284 	P->status.pr_ppid = (pid_t)-1;
285 	P->status.pr_pgid = (pid_t)-1;
286 	P->status.pr_sid = (pid_t)-1;
287 	P->status.pr_taskid = (taskid_t)-1;
288 	P->status.pr_projid = (projid_t)-1;
289 	P->status.pr_zoneid = (zoneid_t)-1;
290 	switch (ehdr.e_ident[EI_CLASS]) {
291 	case ELFCLASS32:
292 		P->status.pr_dmodel = PR_MODEL_ILP32;
293 		break;
294 	case ELFCLASS64:
295 		P->status.pr_dmodel = PR_MODEL_LP64;
296 		break;
297 	default:
298 		*perr = G_FORMAT;
299 		goto err;
300 	}
301 
302 	/*
303 	 * Pfindobj() checks what zone a process is associated with, so
304 	 * we call it after initializing pr_zoneid to -1.  This ensures
305 	 * we don't get associated with any zone on the system.
306 	 */
307 	if (Pfindobj(P, fp->file_lname, buf, sizeof (buf)) != NULL) {
308 		free(P->execname);
309 		P->execname = strdup(buf);
310 		if ((fp->file_rname = strdup(buf)) != NULL)
311 			fp->file_rbase = basename(fp->file_rname);
312 	}
313 
314 	/*
315 	 * The file and map lists are complete, and will never need to be
316 	 * adjusted.
317 	 */
318 	P->info_valid = 1;
319 
320 	return (P);
321 err:
322 	(void) close(fd);
323 	if (P != NULL)
324 		Pfree(P);
325 	if (elf != NULL)
326 		(void) elf_end(elf);
327 	return (NULL);
328 }
329