rtld_db.c revision 269720
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: stable/10/lib/librtld_db/rtld_db.c 269720 2014-08-08 14:53:01Z markj $"); 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 46static 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 54void 55rd_delete(rd_agent_t *rdap) 56{ 57 58 free(rdap); 59} 60 61const char * 62rd_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 83rd_err_e 84rd_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 114rd_err_e 115rd_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 122rd_err_e 123rd_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 133rd_err_e 134rd_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 146rd_err_e 147rd_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 185void 186rd_log(const int onoff) 187{ 188 DPRINTF("%s\n", __func__); 189 190 (void)onoff; 191} 192 193rd_agent_t * 194rd_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 208rd_err_e 209rd_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 219rd_err_e 220rd_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 234rd_err_e 235rd_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