xref: /illumos-gate/usr/src/lib/libproc/common/Pidle.c (revision 56f33205c9ed776c3c909e07d52e94610a675740)
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 #include <stdlib.h>
27 #include <libelf.h>
28 #include <libgen.h>
29 #include <string.h>
30 #include <strings.h>
31 #include <errno.h>
32 #include <sys/sysmacros.h>
33 
34 #include "libproc.h"
35 #include "Pcontrol.h"
36 
37 static ssize_t
38 Pread_idle(struct ps_prochandle *P, void *buf, size_t n, uintptr_t addr)
39 {
40 	size_t resid = n;
41 
42 	while (resid > 0) {
43 		map_info_t *mp;
44 		uintptr_t mapoff;
45 		ssize_t len;
46 		off64_t off;
47 
48 		if ((mp = Paddr2mptr(P, addr)) == NULL)
49 			break;
50 
51 		mapoff = addr - mp->map_pmap.pr_vaddr;
52 		len = MIN(resid, mp->map_pmap.pr_size - mapoff);
53 		off = mp->map_offset + mapoff;
54 
55 		if ((len = pread64(P->asfd, buf, len, off)) <= 0)
56 			break;
57 
58 		resid -= len;
59 		addr += len;
60 		buf = (char *)buf + len;
61 	}
62 
63 	return (n - resid);
64 }
65 
66 /*ARGSUSED*/
67 static ssize_t
68 Pwrite_idle(struct ps_prochandle *P, const void *buf, size_t n, uintptr_t addr)
69 {
70 	errno = EIO;
71 	return (-1);
72 }
73 
74 static const ps_rwops_t P_idle_ops = {
75 	Pread_idle,
76 	Pwrite_idle
77 };
78 
79 static int
80 idle_add_mapping(struct ps_prochandle *P, GElf_Phdr *php, file_info_t *fp)
81 {
82 	prmap_t pmap;
83 
84 	dprintf("mapping base %llx filesz %llu memsz %llu offset %llu\n",
85 	    (u_longlong_t)php->p_vaddr, (u_longlong_t)php->p_filesz,
86 	    (u_longlong_t)php->p_memsz, (u_longlong_t)php->p_offset);
87 
88 	pmap.pr_vaddr = (uintptr_t)php->p_vaddr;
89 	pmap.pr_size = php->p_filesz;
90 	(void) strncpy(pmap.pr_mapname, fp->file_pname,
91 	    sizeof (pmap.pr_mapname));
92 	pmap.pr_offset = php->p_offset;
93 
94 	pmap.pr_mflags = 0;
95 	if (php->p_flags & PF_R)
96 		pmap.pr_mflags |= MA_READ;
97 	if (php->p_flags & PF_W)
98 		pmap.pr_mflags |= MA_WRITE;
99 	if (php->p_flags & PF_X)
100 		pmap.pr_mflags |= MA_EXEC;
101 
102 	pmap.pr_pagesize = 0;
103 	pmap.pr_shmid = -1;
104 
105 	return (Padd_mapping(P, php->p_offset, fp, &pmap));
106 }
107 
108 struct ps_prochandle *
109 Pgrab_file(const char *fname, int *perr)
110 {
111 	struct ps_prochandle *P = NULL;
112 	char buf[PATH_MAX];
113 	GElf_Ehdr ehdr;
114 	Elf *elf = NULL;
115 	size_t phnum;
116 	file_info_t *fp = NULL;
117 	int fd;
118 	int i;
119 
120 	if ((fd = open64(fname, O_RDONLY)) < 0) {
121 		dprintf("couldn't open file");
122 		*perr = (errno == ENOENT) ? G_NOEXEC : G_STRANGE;
123 		return (NULL);
124 	}
125 
126 	if (elf_version(EV_CURRENT) == EV_NONE) {
127 		dprintf("libproc ELF version is more recent than libelf");
128 		*perr = G_ELF;
129 		goto err;
130 	}
131 
132 	if ((P = calloc(1, sizeof (struct ps_prochandle))) == NULL) {
133 		*perr = G_STRANGE;
134 		goto err;
135 	}
136 
137 	(void) mutex_init(&P->proc_lock, USYNC_THREAD, NULL);
138 	P->state = PS_IDLE;
139 	P->pid = (pid_t)-1;
140 	P->asfd = fd;
141 	P->ctlfd = -1;
142 	P->statfd = -1;
143 	P->agentctlfd = -1;
144 	P->agentstatfd = -1;
145 	P->info_valid = -1;
146 	P->ops = &P_idle_ops;
147 	Pinitsym(P);
148 
149 	if ((elf = elf_begin(fd, ELF_C_READ, NULL)) == NULL) {
150 		*perr = G_ELF;
151 		return (NULL);
152 	}
153 
154 	/*
155 	 * Construct a file_info_t that corresponds to this file.
156 	 */
157 	if ((fp = calloc(1, sizeof (file_info_t))) == NULL) {
158 		*perr = G_STRANGE;
159 		goto err;
160 	}
161 
162 	if ((fp->file_lo = calloc(1, sizeof (rd_loadobj_t))) == NULL) {
163 		*perr = G_STRANGE;
164 		goto err;
165 	}
166 
167 	if (*fname == '/') {
168 		(void) strncpy(fp->file_pname, fname, sizeof (fp->file_pname));
169 	} else {
170 		size_t sz;
171 
172 		if (getcwd(fp->file_pname, sizeof (fp->file_pname) - 1) ==
173 		    NULL) {
174 			*perr = G_STRANGE;
175 			goto err;
176 		}
177 
178 		sz = strlen(fp->file_pname);
179 		(void) snprintf(&fp->file_pname[sz],
180 		    sizeof (fp->file_pname) - sz, "/%s", fname);
181 	}
182 
183 	fp->file_fd = fd;
184 	fp->file_lo->rl_lmident = LM_ID_BASE;
185 	if ((fp->file_lname = strdup(fp->file_pname)) == NULL) {
186 		*perr = G_STRANGE;
187 		goto err;
188 	}
189 	fp->file_lbase = basename(fp->file_lname);
190 
191 	if ((P->execname = strdup(fp->file_pname)) == NULL) {
192 		*perr = G_STRANGE;
193 		goto err;
194 	}
195 
196 	P->num_files++;
197 	list_link(fp, &P->file_head);
198 
199 	if (gelf_getehdr(elf, &ehdr) == NULL) {
200 		*perr = G_STRANGE;
201 		goto err;
202 	}
203 
204 	if (elf_getphdrnum(elf, &phnum) == -1) {
205 		*perr = G_STRANGE;
206 		goto err;
207 	}
208 
209 	dprintf("Pgrab_file: program header count = %lu\n", (ulong_t)phnum);
210 
211 	/*
212 	 * Sift through the program headers making the relevant maps.
213 	 */
214 	for (i = 0; i < phnum; i++) {
215 		GElf_Phdr phdr, *php;
216 
217 		if ((php = gelf_getphdr(elf, i, &phdr)) == NULL) {
218 			*perr = G_STRANGE;
219 			goto err;
220 		}
221 
222 		if (php->p_type != PT_LOAD)
223 			continue;
224 
225 		if (idle_add_mapping(P, php, fp) != 0) {
226 			*perr = G_STRANGE;
227 			goto err;
228 		}
229 	}
230 	Psort_mappings(P);
231 
232 	(void) elf_end(elf);
233 
234 	P->map_exec = fp->file_map;
235 
236 	P->status.pr_flags = PR_STOPPED;
237 	P->status.pr_nlwp = 0;
238 	P->status.pr_pid = (pid_t)-1;
239 	P->status.pr_ppid = (pid_t)-1;
240 	P->status.pr_pgid = (pid_t)-1;
241 	P->status.pr_sid = (pid_t)-1;
242 	P->status.pr_taskid = (taskid_t)-1;
243 	P->status.pr_projid = (projid_t)-1;
244 	P->status.pr_zoneid = (zoneid_t)-1;
245 	switch (ehdr.e_ident[EI_CLASS]) {
246 	case ELFCLASS32:
247 		P->status.pr_dmodel = PR_MODEL_ILP32;
248 		break;
249 	case ELFCLASS64:
250 		P->status.pr_dmodel = PR_MODEL_LP64;
251 		break;
252 	default:
253 		*perr = G_FORMAT;
254 		goto err;
255 	}
256 
257 	/*
258 	 * Pfindobj() checks what zone a process is associated with, so
259 	 * we call it after initializing pr_zoneid to -1.  This ensures
260 	 * we don't get associated with any zone on the system.
261 	 */
262 	if (Pfindobj(P, fp->file_lname, buf, sizeof (buf)) != NULL) {
263 		free(P->execname);
264 		P->execname = strdup(buf);
265 		if ((fp->file_rname = strdup(buf)) != NULL)
266 			fp->file_rbase = basename(fp->file_rname);
267 	}
268 
269 	/*
270 	 * The file and map lists are complete, and will never need to be
271 	 * adjusted.
272 	 */
273 	P->info_valid = 1;
274 
275 	return (P);
276 err:
277 	(void) close(fd);
278 	if (P != NULL)
279 		Pfree(P);
280 	if (elf != NULL)
281 		(void) elf_end(elf);
282 	return (NULL);
283 }
284