1 /*
2 * Copyright (c) 2010 The FreeBSD Foundation
3 * All rights reserved.
4 *
5 * This software was developed by Rui Paulo under sponsorship from the
6 * FreeBSD Foundation.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31
32 #include <machine/_inttypes.h>
33 #include <sys/types.h>
34 #include <sys/user.h>
35
36 #include <err.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <string.h>
40 #include <limits.h>
41 #include <libproc.h>
42 #include <libutil.h>
43
44 #include "rtld_db.h"
45
46 static int _librtld_db_debug = 0;
47 #define DPRINTF(...) do { \
48 if (_librtld_db_debug) { \
49 fprintf(stderr, "librtld_db: DEBUG: "); \
50 fprintf(stderr, __VA_ARGS__); \
51 } \
52 } while (0)
53
54 void
rd_delete(rd_agent_t * rdap)55 rd_delete(rd_agent_t *rdap)
56 {
57
58 free(rdap);
59 }
60
61 const char *
rd_errstr(rd_err_e rderr)62 rd_errstr(rd_err_e rderr)
63 {
64
65 switch (rderr) {
66 case RD_ERR:
67 return "generic error";
68 case RD_OK:
69 return "no error";
70 case RD_NOCAPAB:
71 return "capability not supported";
72 case RD_DBERR:
73 return "database error";
74 case RD_NOBASE:
75 return "NOBASE";
76 case RD_NOMAPS:
77 return "NOMAPS";
78 default:
79 return "unknown error";
80 }
81 }
82
83 rd_err_e
rd_event_addr(rd_agent_t * rdap,rd_event_e event,rd_notify_t * notify)84 rd_event_addr(rd_agent_t *rdap, rd_event_e event, rd_notify_t *notify)
85 {
86 rd_err_e ret;
87
88 DPRINTF("%s rdap %p event %d notify %p\n", __func__, rdap, event,
89 notify);
90
91 ret = RD_OK;
92 switch (event) {
93 case RD_NONE:
94 break;
95 case RD_PREINIT:
96 notify->type = RD_NOTIFY_BPT;
97 notify->u.bptaddr = rdap->rda_preinit_addr;
98 break;
99 case RD_POSTINIT:
100 notify->type = RD_NOTIFY_BPT;
101 notify->u.bptaddr = rdap->rda_postinit_addr;
102 break;
103 case RD_DLACTIVITY:
104 notify->type = RD_NOTIFY_BPT;
105 notify->u.bptaddr = rdap->rda_dlactivity_addr;
106 break;
107 default:
108 ret = RD_ERR;
109 break;
110 }
111 return (ret);
112 }
113
114 rd_err_e
rd_event_enable(rd_agent_t * rdap __unused,int onoff)115 rd_event_enable(rd_agent_t *rdap __unused, int onoff)
116 {
117 DPRINTF("%s onoff %d\n", __func__, onoff);
118
119 return (RD_OK);
120 }
121
122 rd_err_e
rd_event_getmsg(rd_agent_t * rdap __unused,rd_event_msg_t * msg)123 rd_event_getmsg(rd_agent_t *rdap __unused, rd_event_msg_t *msg)
124 {
125 DPRINTF("%s\n", __func__);
126
127 msg->type = RD_POSTINIT;
128 msg->u.state = RD_CONSISTENT;
129
130 return (RD_OK);
131 }
132
133 rd_err_e
rd_init(int version)134 rd_init(int version)
135 {
136 char *debug = NULL;
137
138 if (version == RD_VERSION) {
139 debug = getenv("LIBRTLD_DB_DEBUG");
140 _librtld_db_debug = debug ? atoi(debug) : 0;
141 return (RD_OK);
142 } else
143 return (RD_NOCAPAB);
144 }
145
146 rd_err_e
rd_loadobj_iter(rd_agent_t * rdap,rl_iter_f * cb,void * clnt_data)147 rd_loadobj_iter(rd_agent_t *rdap, rl_iter_f *cb, void *clnt_data)
148 {
149 int cnt, i, lastvn = 0;
150 rd_loadobj_t rdl;
151 struct kinfo_vmentry *kves, *kve;
152
153 DPRINTF("%s\n", __func__);
154
155 if ((kves = kinfo_getvmmap(proc_getpid(rdap->rda_php), &cnt)) == NULL) {
156 warn("ERROR: kinfo_getvmmap() failed");
157 return (RD_ERR);
158 }
159 for (i = 0; i < cnt; i++) {
160 kve = kves + i;
161 if (kve->kve_type == KVME_TYPE_VNODE)
162 lastvn = i;
163 memset(&rdl, 0, sizeof(rdl));
164 /*
165 * Map the kinfo_vmentry struct to the rd_loadobj structure.
166 */
167 rdl.rdl_saddr = kve->kve_start;
168 rdl.rdl_eaddr = kve->kve_end;
169 rdl.rdl_offset = kve->kve_offset;
170 if (kve->kve_protection & KVME_PROT_READ)
171 rdl.rdl_prot |= RD_RDL_R;
172 if (kve->kve_protection & KVME_PROT_WRITE)
173 rdl.rdl_prot |= RD_RDL_W;
174 if (kve->kve_protection & KVME_PROT_EXEC)
175 rdl.rdl_prot |= RD_RDL_X;
176 strlcpy(rdl.rdl_path, kves[lastvn].kve_path,
177 sizeof(rdl.rdl_path));
178 (*cb)(&rdl, clnt_data);
179 }
180 free(kves);
181
182 return (RD_OK);
183 }
184
185 void
rd_log(const int onoff)186 rd_log(const int onoff)
187 {
188 DPRINTF("%s\n", __func__);
189
190 (void)onoff;
191 }
192
193 rd_agent_t *
rd_new(struct proc_handle * php)194 rd_new(struct proc_handle *php)
195 {
196 rd_agent_t *rdap;
197
198 rdap = malloc(sizeof(rd_agent_t));
199 if (rdap) {
200 memset(rdap, 0, sizeof(rd_agent_t));
201 rdap->rda_php = php;
202 rd_reset(rdap);
203 }
204
205 return (rdap);
206 }
207
208 rd_err_e
rd_objpad_enable(rd_agent_t * rdap,size_t padsize)209 rd_objpad_enable(rd_agent_t *rdap, size_t padsize)
210 {
211 DPRINTF("%s\n", __func__);
212
213 (void)rdap;
214 (void)padsize;
215
216 return (RD_ERR);
217 }
218
219 rd_err_e
rd_plt_resolution(rd_agent_t * rdap,uintptr_t pc,struct proc * proc,uintptr_t plt_base,rd_plt_info_t * rpi)220 rd_plt_resolution(rd_agent_t *rdap, uintptr_t pc, struct proc *proc,
221 uintptr_t plt_base, rd_plt_info_t *rpi)
222 {
223 DPRINTF("%s\n", __func__);
224
225 (void)rdap;
226 (void)pc;
227 (void)proc;
228 (void)plt_base;
229 (void)rpi;
230
231 return (RD_ERR);
232 }
233
234 rd_err_e
rd_reset(rd_agent_t * rdap)235 rd_reset(rd_agent_t *rdap)
236 {
237 GElf_Sym sym;
238
239 if (proc_name2sym(rdap->rda_php, "ld-elf.so.1", "r_debug_state",
240 &sym) < 0)
241 return (RD_ERR);
242 DPRINTF("found r_debug_state at 0x%lx\n", (unsigned long)sym.st_value);
243 rdap->rda_preinit_addr = sym.st_value;
244 rdap->rda_dlactivity_addr = sym.st_value;
245
246 if (proc_name2sym(rdap->rda_php, "ld-elf.so.1", "_r_debug_postinit",
247 &sym) < 0)
248 return (RD_ERR);
249 DPRINTF("found _r_debug_postinit at 0x%lx\n",
250 (unsigned long)sym.st_value);
251 rdap->rda_postinit_addr = sym.st_value;
252
253 return (RD_OK);
254 }
255