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 2006 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 /* 29 * Object file dependent suport for ELF objects. 30 */ 31 #include "_synonyms.h" 32 33 #include <sys/mman.h> 34 #include <stdio.h> 35 #include <unistd.h> 36 #include <libelf.h> 37 #include <string.h> 38 #include <dlfcn.h> 39 #include <debug.h> 40 #include <libld.h> 41 #include "_rtld.h" 42 #include "_audit.h" 43 #include "_elf.h" 44 45 static Rt_map *olmp = 0; 46 47 static Ehdr dehdr = { { ELFMAG0, ELFMAG1, ELFMAG2, ELFMAG3, 48 M_CLASS, M_DATA }, 0, M_MACH, EV_CURRENT }; 49 50 /* 51 * Process a relocatable object. The static object link map pointer is used as 52 * a flag to determine whether a concatenation is already in progress (ie. an 53 * LD_PRELOAD may specify a list of objects). The link map returned simply 54 * specifies an `object' flag which the caller can interpret and thus call 55 * elf_obj_fini() to complete the concatenation. 56 */ 57 static Rt_map * 58 elf_obj_init(Lm_list *lml, Aliste lmco, const char *name) 59 { 60 Ofl_desc * ofl; 61 62 /* 63 * Initialize an output file descriptor and the entrance criteria. 64 */ 65 if ((ofl = (Ofl_desc *)calloc(sizeof (Ofl_desc), 1)) == 0) 66 return (0); 67 68 ofl->ofl_dehdr = &dehdr; 69 70 ofl->ofl_flags = (FLG_OF_DYNAMIC | FLG_OF_SHAROBJ | FLG_OF_STRIP); 71 ofl->ofl_flags1 = (FLG_OF1_RELDYN | FLG_OF1_TEXTOFF | FLG_OF1_MEMORY); 72 ofl->ofl_lml = lml; 73 74 /* 75 * As ent_setup() will effectively lazy load the necessary support 76 * libraries, make sure ld.so.1 is initialized for plt relocations. 77 */ 78 if (elf_rtld_load() == 0) 79 return (0); 80 81 /* 82 * Obtain a generic set of entrance criteria (this is the first call to 83 * libld.so, which will effectively lazyload it). 84 */ 85 if (ld_ent_setup(ofl, syspagsz) == S_ERROR) 86 return (0); 87 88 /* 89 * Generate a link map place holder and use the `rt_priv' element to 90 * maintain the output file descriptor. 91 */ 92 if ((olmp = (Rt_map *)calloc(sizeof (Rt_map), 1)) == 0) 93 return (0); 94 95 DBG_CALL(Dbg_file_elf(lml, name, 0, 0, 0, 0, lml->lm_lmidstr, lmco)); 96 FLAGS(olmp) |= FLG_RT_OBJECT; 97 olmp->rt_priv = (void *)ofl; 98 99 /* 100 * Initialize string tables. 101 */ 102 if (ld_init_strings(ofl) == S_ERROR) 103 return (0); 104 105 /* 106 * Assign the output file name to be the initial object that got us 107 * here. This name is being used for diagnostic purposes only as we 108 * don't actually generate an output file unless debugging is enabled. 109 */ 110 ofl->ofl_name = name; 111 ORIGNAME(olmp) = PATHNAME(olmp) = NAME(olmp) = (char *)name; 112 LIST(olmp) = lml; 113 114 lm_append(lml, lmco, olmp); 115 return (olmp); 116 } 117 118 /* 119 * Initial processing of a relocatable object. If this is the first object 120 * encountered we need to initialize some structures, then simply call the 121 * link-edit functionality to provide the initial processing of the file (ie. 122 * reads in sections and symbols, performs symbol resolution if more that one 123 * object file have been specified, and assigns input sections to output 124 * sections). 125 */ 126 Rt_map * 127 elf_obj_file(Lm_list *lml, Aliste lmco, const char *name, int fd) 128 { 129 Rej_desc rej; 130 131 /* 132 * If this is the first relocatable object (LD_PRELOAD could provide a 133 * list of objects), initialize an input file descriptor and a link map. 134 */ 135 if (!olmp) { 136 /* 137 * Load the link-editor library. 138 */ 139 if ((olmp = elf_obj_init(lml, lmco, name)) == 0) 140 return (0); 141 } 142 143 /* 144 * Proceed to process the input file. 145 */ 146 DBG_CALL(Dbg_util_nl(lml, DBG_NL_STD)); 147 if (ld_process_open(name, name, &fd, (Ofl_desc *)olmp->rt_priv, 148 NULL, &rej) == (Ifl_desc *)S_ERROR) 149 return (0); 150 return (olmp); 151 } 152 153 /* 154 * Finish relocatable object processing. Having already initially processed one 155 * or more objects, complete the generation of a shared object image by calling 156 * the appropriate link-edit functionality (refer to sgs/ld/common/main.c). 157 */ 158 Rt_map * 159 elf_obj_fini(Lm_list *lml, Rt_map *lmp) 160 { 161 Ofl_desc *ofl = (Ofl_desc *)lmp->rt_priv; 162 Rt_map *nlmp; 163 Addr etext; 164 Ehdr *ehdr; 165 Phdr *phdr; 166 Mmap *mmaps; 167 uint_t phnum, mmapcnt; 168 Lm_cntl *lmc; 169 170 DBG_CALL(Dbg_util_nl(lml, DBG_NL_STD)); 171 172 if (ld_reloc_init(ofl) == S_ERROR) 173 return (0); 174 if (ld_sym_validate(ofl) == S_ERROR) 175 return (0); 176 if (ld_make_sections(ofl) == S_ERROR) 177 return (0); 178 if (ld_create_outfile(ofl) == S_ERROR) 179 return (0); 180 if ((etext = ld_update_outfile(ofl)) == (Addr)S_ERROR) 181 return (0); 182 if (ld_reloc_process(ofl) == S_ERROR) 183 return (0); 184 185 /* 186 * At this point we have a memory image of the shared object. The link 187 * editor would normally simply write this to the required output file. 188 * If we're debugging generate a standard temporary output file. 189 */ 190 DBG_CALL(Dbg_file_output(ofl)); 191 192 /* 193 * Allocate a mapping array to retain mapped segment information. 194 */ 195 ehdr = ofl->ofl_nehdr; 196 phdr = ofl->ofl_phdr; 197 if ((mmaps = calloc(ehdr->e_phnum, sizeof (Mmap))) == 0) 198 return (0); 199 for (mmapcnt = 0, phnum = 0; phnum < ehdr->e_phnum; phnum++) { 200 if (phdr[phnum].p_type != PT_LOAD) 201 continue; 202 203 mmaps[mmapcnt].m_vaddr = (caddr_t) 204 (phdr[phnum].p_vaddr + (ulong_t)ehdr); 205 mmaps[mmapcnt].m_msize = phdr[phnum].p_memsz; 206 mmaps[mmapcnt].m_fsize = phdr[phnum].p_filesz; 207 mmaps[mmapcnt].m_perm = (PROT_READ | PROT_WRITE | PROT_EXEC); 208 mmapcnt++; 209 } 210 211 /* 212 * Generate a new link map representing the memory image created. 213 */ 214 if ((nlmp = elf_new_lm(lml, ofl->ofl_name, ofl->ofl_name, 215 ofl->ofl_osdynamic->os_outdata->d_buf, (ulong_t)ehdr, 216 (ulong_t)ehdr + etext, CNTL(olmp), (ulong_t)ofl->ofl_size, 217 0, 0, 0, mmaps, mmapcnt)) == 0) 218 return (0); 219 220 /* 221 * Remove this link map from the end of the link map list and copy its 222 * contents into the link map originally created for this file (we copy 223 * the contents rather than manipulate the link map pointers as parts 224 * of the dlopen code have remembered the original link map address). 225 */ 226 NEXT((Rt_map *)PREV(nlmp)) = 0; 227 /* LINTED */ 228 lmc = (Lm_cntl *)((char *)lml->lm_lists + CNTL(nlmp)); 229 lmc->lc_tail = (Rt_map *)PREV(nlmp); 230 if (CNTL(nlmp) == ALO_DATA) 231 lml->lm_tail = (Rt_map *)PREV(nlmp); 232 lml->lm_obj--; 233 234 PREV(nlmp) = PREV(olmp); 235 NEXT(nlmp) = NEXT(olmp); 236 HANDLES(nlmp) = HANDLES(olmp); 237 GROUPS(nlmp) = GROUPS(olmp); 238 STDEV(nlmp) = STDEV(olmp); 239 STINO(nlmp) = STINO(olmp); 240 241 FLAGS(nlmp) |= ((FLAGS(olmp) & ~FLG_RT_OBJECT) | FLG_RT_IMGALLOC); 242 FLAGS1(nlmp) |= FLAGS1(olmp); 243 MODE(nlmp) |= MODE(olmp); 244 245 NAME(nlmp) = NAME(olmp); 246 PATHNAME(nlmp) = PATHNAME(olmp); 247 ORIGNAME(nlmp) = ORIGNAME(olmp); 248 DIRSZ(nlmp) = DIRSZ(olmp); 249 250 ld_ofl_cleanup(ofl); 251 free(olmp->rt_priv); 252 (void) memcpy(olmp, nlmp, sizeof (Rt_map)); 253 free(nlmp); 254 nlmp = olmp; 255 olmp = 0; 256 257 /* 258 * Now that we've allocated our permanent Rt_map structure, expand the 259 * PATHNAME() and insert it into the FullpathNode AVL tree 260 */ 261 if (FLAGS1(nlmp) & FL1_RT_RELATIVE) 262 (void) fullpath(nlmp, 0); 263 if (fpavl_insert(lml, nlmp, PATHNAME(nlmp), 0) == 0) 264 return (0); 265 266 /* 267 * If we're being audited tell the audit library of the file we've just 268 * opened. 269 */ 270 if ((lml->lm_tflags | FLAGS1(nlmp)) & LML_TFLG_AUD_MASK) { 271 if (audit_objopen(lmp, lmp) == 0) 272 return (0); 273 } 274 return (nlmp); 275 } 276