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 #ifdef __FBSDID 31 __FBSDID("$FreeBSD: head/lib/librtld_db/rtld_db.c 272488 2014-10-03 23:20:37Z markj $"); 32 #else 33 __RCSID("$NetBSD: rtld_db.c,v 1.3 2016/04/26 14:26:49 chs Exp $"); 34 #endif 35 36 #include <sys/types.h> 37 #include <sys/sysctl.h> 38 39 #include <inttypes.h> 40 #include <err.h> 41 #include <stdio.h> 42 #include <stdlib.h> 43 #include <string.h> 44 #include <limits.h> 45 #include <libproc.h> 46 #include <util.h> 47 48 #include "rtld_db.h" 49 50 static int _librtld_db_debug = 0; 51 #define DPRINTF(...) do { \ 52 if (_librtld_db_debug) { \ 53 fprintf(stderr, "librtld_db: DEBUG: "); \ 54 fprintf(stderr, __VA_ARGS__); \ 55 } \ 56 } while (0) 57 58 void 59 rd_delete(rd_agent_t *rdap) 60 { 61 62 free(rdap); 63 } 64 65 const char * 66 rd_errstr(rd_err_e rderr) 67 { 68 69 switch (rderr) { 70 case RD_ERR: 71 return "generic error"; 72 case RD_OK: 73 return "no error"; 74 case RD_NOCAPAB: 75 return "capability not supported"; 76 case RD_DBERR: 77 return "database error"; 78 case RD_NOBASE: 79 return "NOBASE"; 80 case RD_NOMAPS: 81 return "NOMAPS"; 82 default: 83 return "unknown error"; 84 } 85 } 86 87 rd_err_e 88 rd_event_addr(rd_agent_t *rdap, rd_event_e event, rd_notify_t *notify) 89 { 90 rd_err_e ret; 91 92 DPRINTF("%s rdap %p event %d notify %p\n", __func__, rdap, event, 93 notify); 94 95 ret = RD_OK; 96 switch (event) { 97 case RD_NONE: 98 break; 99 case RD_PREINIT: 100 notify->type = RD_NOTIFY_BPT; 101 notify->u.bptaddr = rdap->rda_preinit_addr; 102 break; 103 case RD_POSTINIT: 104 notify->type = RD_NOTIFY_BPT; 105 notify->u.bptaddr = rdap->rda_postinit_addr; 106 break; 107 case RD_DLACTIVITY: 108 notify->type = RD_NOTIFY_BPT; 109 notify->u.bptaddr = rdap->rda_dlactivity_addr; 110 break; 111 default: 112 ret = RD_ERR; 113 break; 114 } 115 return (ret); 116 } 117 118 rd_err_e 119 rd_event_enable(rd_agent_t *rdap __unused, int onoff) 120 { 121 DPRINTF("%s onoff %d\n", __func__, onoff); 122 123 return (RD_OK); 124 } 125 126 rd_err_e 127 rd_event_getmsg(rd_agent_t *rdap __unused, rd_event_msg_t *msg) 128 { 129 DPRINTF("%s\n", __func__); 130 131 msg->type = RD_POSTINIT; 132 msg->u.state = RD_CONSISTENT; 133 134 return (RD_OK); 135 } 136 137 rd_err_e 138 rd_init(int version) 139 { 140 char *debug = NULL; 141 142 if (version == RD_VERSION) { 143 debug = getenv("LIBRTLD_DB_DEBUG"); 144 _librtld_db_debug = debug ? atoi(debug) : 0; 145 return (RD_OK); 146 } else 147 return (RD_NOCAPAB); 148 } 149 150 rd_err_e 151 rd_loadobj_iter(rd_agent_t *rdap, rl_iter_f *cb, void *clnt_data) 152 { 153 size_t cnt, i, lastvn = 0; 154 rd_loadobj_t rdl; 155 struct kinfo_vmentry *kves, *kve; 156 157 DPRINTF("%s\n", __func__); 158 159 if ((kves = kinfo_getvmmap(proc_getpid(rdap->rda_php), &cnt)) == NULL) { 160 warn("ERROR: kinfo_getvmmap() failed"); 161 return (RD_ERR); 162 } 163 for (i = 0; i < cnt; i++) { 164 kve = kves + i; 165 if (kve->kve_type == KVME_TYPE_VNODE) 166 lastvn = i; 167 memset(&rdl, 0, sizeof(rdl)); 168 /* 169 * Map the kinfo_vmentry struct to the rd_loadobj structure. 170 */ 171 rdl.rdl_saddr = kve->kve_start; 172 rdl.rdl_eaddr = kve->kve_end; 173 rdl.rdl_offset = kve->kve_offset; 174 if (kve->kve_protection & KVME_PROT_READ) 175 rdl.rdl_prot |= RD_RDL_R; 176 if (kve->kve_protection & KVME_PROT_WRITE) 177 rdl.rdl_prot |= RD_RDL_W; 178 if (kve->kve_protection & KVME_PROT_EXEC) 179 rdl.rdl_prot |= RD_RDL_X; 180 strlcpy(rdl.rdl_path, kves[lastvn].kve_path, 181 sizeof(rdl.rdl_path)); 182 (*cb)(&rdl, clnt_data); 183 } 184 free(kves); 185 186 return (RD_OK); 187 } 188 189 void 190 rd_log(const int onoff) 191 { 192 DPRINTF("%s\n", __func__); 193 194 (void)onoff; 195 } 196 197 rd_agent_t * 198 rd_new(struct proc_handle *php) 199 { 200 rd_agent_t *rdap; 201 202 rdap = malloc(sizeof(rd_agent_t)); 203 if (rdap) { 204 memset(rdap, 0, sizeof(rd_agent_t)); 205 rdap->rda_php = php; 206 rd_reset(rdap); 207 } 208 209 return (rdap); 210 } 211 212 rd_err_e 213 rd_objpad_enable(rd_agent_t *rdap, size_t padsize) 214 { 215 DPRINTF("%s\n", __func__); 216 217 (void)rdap; 218 (void)padsize; 219 220 return (RD_ERR); 221 } 222 223 rd_err_e 224 rd_plt_resolution(rd_agent_t *rdap, uintptr_t pc, struct proc *proc, 225 uintptr_t plt_base, rd_plt_info_t *rpi) 226 { 227 DPRINTF("%s\n", __func__); 228 229 (void)rdap; 230 (void)pc; 231 (void)proc; 232 (void)plt_base; 233 (void)rpi; 234 235 return (RD_ERR); 236 } 237 238 rd_err_e 239 rd_reset(rd_agent_t *rdap) 240 { 241 GElf_Sym sym; 242 243 /* 244 * preinit and dlactivity events are not supported yet. 245 */ 246 247 rdap->rda_preinit_addr = (uintptr_t)-1; 248 rdap->rda_dlactivity_addr = (uintptr_t)-1; 249 250 if (proc_name2sym(rdap->rda_php, "ld.elf_so", "_rtld_debug_state", 251 &sym, NULL) < 0) 252 return (RD_ERR); 253 DPRINTF("found _rtld_debug_state at 0x%lx\n", 254 (unsigned long)sym.st_value); 255 rdap->rda_postinit_addr = sym.st_value; 256 257 return (RD_OK); 258 } 259