xref: /illumos-gate/usr/src/cmd/sgs/link_audit/common/who.c (revision 0250c53ad267726f2438e3c6556199a0bbf588a2)
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 (c) 1989, 2010, Oracle and/or its affiliates. All rights reserved.
24  */
25 #include <stdio.h>
26 #include <fcntl.h>
27 #include <link.h>
28 #include <stdlib.h>
29 #include <unistd.h>
30 #include <strings.h>
31 #include <sys/regset.h>
32 #include <sys/frame.h>
33 #include <sys/stack.h>
34 #include <signal.h>
35 
36 #include "env.h"
37 #include "mach.h"
38 #include "who.h"
39 
40 
41 static int	detail_syms = 0;	/* display detail symbol information */
42 static Objinfo	*objhead = NULL;	/* head of object list */
43 static Elist	*funclist = NULL;
44 static sigset_t	iset;
45 
46 static void
47 add_object(Objinfo **objlist, Link_map *lmp)
48 {
49 	Objinfo		*op, *cur, *prev;
50 	Elf_Ehdr	*ehdr;
51 	Elf_Phdr	*phdr;
52 	caddr_t		lpc, hpc;
53 	int		i;
54 
55 	if ((op = calloc(1, sizeof (Objinfo))) == NULL) {
56 		(void) fprintf(stderr, "who.so.1: calloc failed\n");
57 		exit(1);
58 	}
59 
60 	lpc = hpc = (caddr_t)lmp->l_addr;
61 	/* LINTED */
62 	ehdr = (Elf_Ehdr *)lpc;
63 
64 	/* LINTED */
65 	for (i = 0, phdr = (Elf_Phdr *)(ehdr->e_phoff + lpc);
66 	    i < ehdr->e_phnum; i++, phdr++) {
67 		caddr_t		_hpc;
68 		if ((phdr->p_type == PT_LOAD) &&
69 		    ((_hpc = phdr->p_vaddr + phdr->p_memsz + lpc) > hpc))
70 			hpc = _hpc;
71 	}
72 	op->o_lpc = lpc;
73 	op->o_hpc = hpc;
74 	op->o_lmp = lmp;
75 
76 	if (ehdr->e_type == ET_EXEC)
77 		op->o_flags |= FLG_OB_FIXED;
78 
79 	if (*objlist == NULL) {
80 		*objlist = op;
81 		return;
82 	}
83 	/*
84 	 * Do an insertion sort to maintain the list
85 	 * in order.
86 	 */
87 	if ((*objlist)->o_lmp->l_addr > lmp->l_addr) {
88 		op->o_next = *objlist;
89 		*objlist = op;
90 		return;
91 	}
92 
93 	for (prev = NULL, cur = *objlist; cur; prev = cur, cur = cur->o_next) {
94 		if (lpc < cur->o_lpc)
95 			break;
96 	}
97 	if (prev == NULL) {
98 		op->o_next = *objlist;
99 		*objlist = op;
100 		return;
101 	}
102 	prev->o_next = op;
103 	op->o_next = cur;
104 }
105 
106 static void
107 remove_object(Objinfo **objlist, Link_map *lmp)
108 {
109 	Objinfo	*cur, *prev;
110 
111 	for (prev = NULL, cur = *objlist; cur; prev = cur, cur = cur->o_next) {
112 		if (cur->o_lmp == lmp)
113 			break;
114 	}
115 
116 	/*
117 	 * Did we find it?
118 	 */
119 	if (!cur)
120 		return;
121 
122 	if (!prev)
123 		*objlist = cur->o_next;
124 	else
125 		prev->o_next = cur->o_next;
126 
127 	if (cur->o_elf) {
128 		(void) elf_end(cur->o_elf);
129 		(void) close(cur->o_fd);
130 	}
131 	free(cur);
132 }
133 
134 static void
135 print_simple_address(void *pc)
136 {
137 	Dl_info		info;
138 
139 	if (dladdr(pc, &info) == 0) {
140 		(void) fprintf(stderr,
141 		    "\t<unknown>: 0x%lx\n", (unsigned long)pc);
142 		return;
143 	}
144 
145 	(void) fprintf(stderr, "\t%s:%s+0x%lx\n", info.dli_fname,
146 	    info.dli_sname,
147 	    (ulong_t)((uintptr_t)pc - (uintptr_t)info.dli_saddr));
148 }
149 
150 static void
151 load_syms(Objinfo *op)
152 {
153 	int	fd;
154 	Elf	*elf;
155 	Elf_Scn	*scn;
156 
157 	if (elf_version(EV_CURRENT) == EV_NONE) {
158 		op->o_flags |= FLG_OB_NOSYMS;
159 		return;
160 	}
161 
162 	if ((fd = open(op->o_lmp->l_name, O_RDONLY)) == -1) {
163 		op->o_flags |= FLG_OB_NOSYMS;
164 		return;
165 	}
166 
167 	if ((elf = elf_begin(fd, ELF_C_READ, 0)) == NULL) {
168 		op->o_flags |= FLG_OB_NOSYMS;
169 		(void) close(fd);
170 		return;
171 	}
172 	scn = NULL;
173 	while ((scn = elf_nextscn(elf, scn)) != NULL) {
174 		Elf_Shdr	*shdr;
175 		Elf_Data	*data;
176 
177 		shdr = elf_getshdr(scn);
178 		if (shdr->sh_type != SHT_SYMTAB)
179 			continue;
180 		data = elf_getdata(scn, 0);
181 		op->o_syms = (Elf_Sym *)data->d_buf;
182 		/* LINTED */
183 		op->o_symcnt = (uint_t)(shdr->sh_size / shdr->sh_entsize);
184 		scn = elf_getscn(elf, shdr->sh_link);
185 		data = elf_getdata(scn, 0);
186 		op->o_strs = (const char *)data->d_buf;
187 	}
188 	if (!op->o_syms) {
189 		(void) elf_end(elf);
190 		(void) close(fd);
191 		op->o_flags |= FLG_OB_NOSYMS;
192 	}
193 }
194 
195 
196 static void
197 print_address(caddr_t pc)
198 {
199 	Elf_Sym	*sym, *_sym;
200 	Objinfo	*op;
201 	int	i;
202 
203 	if (!detail_syms) {
204 		print_simple_address(pc);
205 		return;
206 	}
207 	for (op = objhead; op; op = op->o_next) {
208 		if ((pc >= op->o_lpc) && (pc <= op->o_hpc))
209 			break;
210 	}
211 	if (op && (op->o_syms == NULL))
212 		load_syms(op);
213 
214 	if (!op || (op->o_flags & FLG_OB_NOSYMS)) {
215 		print_simple_address(pc);
216 		return;
217 	}
218 
219 	sym = op->o_syms;
220 	if ((op->o_flags & FLG_OB_FIXED) == 0)
221 		pc = (caddr_t)((uintptr_t)pc - (uintptr_t)op->o_lpc);
222 	for (i = 0, _sym = op->o_syms; i < op->o_symcnt; i++, _sym++) {
223 		if (((uintptr_t)_sym->st_value < (uintptr_t)pc) &&
224 		    (_sym->st_value > sym->st_value))
225 			sym = _sym;
226 	}
227 	(void) fprintf(stderr, "\t%s:%s+0x%lx\n", op->o_lmp->l_name,
228 	    sym->st_name + op->o_strs,
229 	    (ulong_t)((uintptr_t)pc - (uintptr_t)sym->st_value));
230 }
231 
232 static void
233 print_stack(struct frame *sp)
234 {
235 	FLUSHWIN();
236 
237 	while (sp && sp->fr_savpc) {
238 		print_address((caddr_t)sp->fr_savpc);
239 		sp = (struct frame *)((ulong_t)sp->fr_savfp + STACK_BIAS);
240 	}
241 }
242 
243 uint_t
244 la_version(uint_t version)
245 {
246 	if (version > LAV_CURRENT)
247 		(void) fprintf(stderr, "who.so: unexpected version: %d\n",
248 		    version);
249 
250 	if (checkenv((const char *)"WHO_DETAIL"))
251 		detail_syms++;
252 
253 	build_env_list(&funclist, (const char *)"WHOCALLS");
254 
255 	/*
256 	 * Initalize iset to the full set of signals to be masked durring
257 	 * pltenter/pltexit
258 	 */
259 	(void) sigfillset(&iset);
260 
261 	return (LAV_CURRENT);
262 }
263 
264 /* ARGSUSED1 */
265 uint_t
266 la_objopen(Link_map *lmp, Lmid_t lmid, uintptr_t *cookie)
267 {
268 	add_object(&objhead, lmp);
269 	return (LA_FLG_BINDTO | LA_FLG_BINDFROM);
270 }
271 
272 uint_t
273 la_objclose(uintptr_t *cookie)
274 {
275 	remove_object(&objhead, (Link_map *)(*cookie));
276 	return (1);
277 }
278 
279 /* ARGSUSED1 */
280 #if	defined(__sparcv9)
281 uintptr_t
282 la_sparcv9_pltenter(Elf64_Sym *symp, uint_t symndx, uintptr_t *refcookie,
283 	uintptr_t *defcookie, La_sparcv9_regs *regset, uint_t *sb_flags,
284 	const char *sym_name)
285 #elif	defined(__sparc)
286 uintptr_t
287 la_sparcv8_pltenter(Elf32_Sym *symp, uint_t symndx, uintptr_t *refcookie,
288 	uintptr_t *defcookie, La_sparcv8_regs *regset, uint_t *sb_flags)
289 #elif   defined(__amd64)
290 uintptr_t
291 la_amd64_pltenter(Elf64_Sym *symp, uint_t symndx, uintptr_t *refcookie,
292 	uintptr_t *defcookie, La_amd64_regs *regset, uint_t *sb_flags,
293 	const char *sym_name)
294 #elif   defined(__i386)
295 uintptr_t
296 la_i86_pltenter(Elf32_Sym *symp, uint_t symndx, uintptr_t *refcooke,
297 	uintptr_t *defcook, La_i86_regs *regset, uint_t *sb_flags)
298 #endif
299 {
300 	sigset_t	oset;
301 #if	!defined(_LP64)
302 	const char	*sym_name = (const char *)symp->st_name;
303 #endif
304 
305 	(void) sigprocmask(SIG_BLOCK, &iset, &oset);
306 	if (check_list(funclist, sym_name)) {
307 		struct frame	*frame_p;
308 
309 		(void) fprintf(stderr, "%s(0x%lx, 0x%lx, 0x%lx)\n", sym_name,
310 		    (long)GETARG0(regset), (long)GETARG1(regset),
311 		    (long)GETARG2(regset));
312 
313 		print_address((caddr_t)GETPREVPC(regset));
314 
315 		frame_p = (struct frame *)((ulong_t)GETFRAME(regset)
316 		    + STACK_BIAS);
317 
318 		print_stack(frame_p);
319 		(void) fflush(stdout);
320 	}
321 	(void) sigprocmask(SIG_SETMASK, &oset, NULL);
322 	return (symp->st_value);
323 }
324