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 = 71 (FLG_OF_DYNAMIC | FLG_OF_SHAROBJ | FLG_OF_STRIP | FLG_OF_MEMORY); 72 ofl->ofl_flags1 = FLG_OF1_RELDYN | FLG_OF1_TEXTOFF; 73 ofl->ofl_lml = lml; 74 75 /* 76 * As ent_setup() will effectively lazy load the necessary support 77 * libraries, make sure ld.so.1 is initialized for plt relocations. 78 */ 79 if (elf_rtld_load() == 0) 80 return (0); 81 82 /* 83 * Obtain a generic set of entrance criteria (this is the first call to 84 * libld.so, which will effectively lazyload it). 85 */ 86 if (ld_ent_setup(ofl, syspagsz) == S_ERROR) 87 return (0); 88 89 /* 90 * Generate a link map place holder and use the `rt_priv' element to 91 * maintain the output file descriptor. 92 */ 93 if ((olmp = (Rt_map *)calloc(sizeof (Rt_map), 1)) == 0) 94 return (0); 95 96 DBG_CALL(Dbg_file_elf(lml, name, 0, 0, 0, 0, lml->lm_lmidstr, lmco)); 97 FLAGS(olmp) |= FLG_RT_OBJECT; 98 olmp->rt_priv = (void *)ofl; 99 100 /* 101 * Initialize string tables. 102 */ 103 if (ld_init_strings(ofl) == S_ERROR) 104 return (0); 105 106 /* 107 * Assign the output file name to be the initial object that got us 108 * here. This name is being used for diagnostic purposes only as we 109 * don't actually generate an output file unless debugging is enabled. 110 */ 111 ofl->ofl_name = name; 112 ORIGNAME(olmp) = PATHNAME(olmp) = NAME(olmp) = (char *)name; 113 LIST(olmp) = lml; 114 115 lm_append(lml, lmco, olmp); 116 return (olmp); 117 } 118 119 /* 120 * Initial processing of a relocatable object. If this is the first object 121 * encountered we need to initialize some structures, then simply call the 122 * link-edit functionality to provide the initial processing of the file (ie. 123 * reads in sections and symbols, performs symbol resolution if more that one 124 * object file have been specified, and assigns input sections to output 125 * sections). 126 */ 127 Rt_map * 128 elf_obj_file(Lm_list *lml, Aliste lmco, const char *name, int fd) 129 { 130 Rej_desc rej; 131 132 /* 133 * If this is the first relocatable object (LD_PRELOAD could provide a 134 * list of objects), initialize an input file descriptor and a link map. 135 */ 136 if (!olmp) { 137 /* 138 * Load the link-editor library. 139 */ 140 if ((olmp = elf_obj_init(lml, lmco, name)) == 0) 141 return (0); 142 } 143 144 /* 145 * Proceed to process the input file. 146 */ 147 DBG_CALL(Dbg_util_nl(lml, DBG_NL_STD)); 148 if (ld_process_open(name, 0, fd, (Ofl_desc *)olmp->rt_priv, 149 NULL, &rej) == (Ifl_desc *)S_ERROR) 150 return (0); 151 return (olmp); 152 } 153 154 /* 155 * Finish relocatable object processing. Having already initially processed one 156 * or more objects, complete the generation of a shared object image by calling 157 * the appropriate link-edit functionality (refer to sgs/ld/common/main.c). 158 */ 159 Rt_map * 160 elf_obj_fini(Lm_list *lml, Rt_map *lmp) 161 { 162 Ofl_desc *ofl = (Ofl_desc *)lmp->rt_priv; 163 Rt_map *nlmp; 164 Addr etext; 165 Ehdr *ehdr; 166 Phdr *phdr; 167 Mmap *mmaps; 168 uint_t phnum, mmapcnt; 169 Lm_cntl *lmc; 170 171 DBG_CALL(Dbg_util_nl(lml, DBG_NL_STD)); 172 173 if (ld_reloc_init(ofl) == S_ERROR) 174 return (0); 175 if (ld_sym_validate(ofl) == S_ERROR) 176 return (0); 177 if (ld_make_sections(ofl) == S_ERROR) 178 return (0); 179 if (ld_create_outfile(ofl) == S_ERROR) 180 return (0); 181 if ((etext = ld_update_outfile(ofl)) == (Addr)S_ERROR) 182 return (0); 183 if (ld_reloc_process(ofl) == S_ERROR) 184 return (0); 185 186 /* 187 * At this point we have a memory image of the shared object. The link 188 * editor would normally simply write this to the required output file. 189 * If we're debugging generate a standard temporary output file. 190 */ 191 DBG_CALL(Dbg_file_output(ofl)); 192 193 /* 194 * Allocate a mapping array to retain mapped segment information. 195 */ 196 ehdr = ofl->ofl_nehdr; 197 phdr = ofl->ofl_phdr; 198 if ((mmaps = calloc(ehdr->e_phnum, sizeof (Mmap))) == 0) 199 return (0); 200 for (mmapcnt = 0, phnum = 0; phnum < ehdr->e_phnum; phnum++) { 201 if (phdr[phnum].p_type != PT_LOAD) 202 continue; 203 204 mmaps[mmapcnt].m_vaddr = (caddr_t) 205 (phdr[phnum].p_vaddr + (ulong_t)ehdr); 206 mmaps[mmapcnt].m_msize = phdr[phnum].p_memsz; 207 mmaps[mmapcnt].m_fsize = phdr[phnum].p_filesz; 208 mmaps[mmapcnt].m_perm = (PROT_READ | PROT_WRITE | PROT_EXEC); 209 mmapcnt++; 210 } 211 212 /* 213 * Generate a new link map representing the memory image created. 214 */ 215 if ((nlmp = elf_new_lm(lml, ofl->ofl_name, ofl->ofl_name, 216 ofl->ofl_osdynamic->os_outdata->d_buf, (ulong_t)ehdr, 217 (ulong_t)ehdr + etext, CNTL(olmp), (ulong_t)ofl->ofl_size, 218 0, 0, 0, mmaps, mmapcnt)) == 0) 219 return (0); 220 221 /* 222 * Remove this link map from the end of the link map list and copy its 223 * contents into the link map originally created for this file (we copy 224 * the contents rather than manipulate the link map pointers as parts 225 * of the dlopen code have remembered the original link map address). 226 */ 227 NEXT((Rt_map *)PREV(nlmp)) = 0; 228 /* LINTED */ 229 lmc = (Lm_cntl *)((char *)lml->lm_lists + CNTL(nlmp)); 230 lmc->lc_tail = (Rt_map *)PREV(nlmp); 231 if (CNTL(nlmp) == ALO_DATA) 232 lml->lm_tail = (Rt_map *)PREV(nlmp); 233 lml->lm_obj--; 234 235 PREV(nlmp) = PREV(olmp); 236 NEXT(nlmp) = NEXT(olmp); 237 HANDLES(nlmp) = HANDLES(olmp); 238 GROUPS(nlmp) = GROUPS(olmp); 239 STDEV(nlmp) = STDEV(olmp); 240 STINO(nlmp) = STINO(olmp); 241 242 FLAGS(nlmp) |= ((FLAGS(olmp) & ~FLG_RT_OBJECT) | FLG_RT_IMGALLOC); 243 FLAGS1(nlmp) |= FLAGS1(olmp); 244 MODE(nlmp) |= MODE(olmp); 245 246 NAME(nlmp) = NAME(olmp); 247 PATHNAME(nlmp) = PATHNAME(olmp); 248 ORIGNAME(nlmp) = ORIGNAME(olmp); 249 DIRSZ(nlmp) = DIRSZ(olmp); 250 251 ld_ofl_cleanup(ofl); 252 free(olmp->rt_priv); 253 (void) memcpy(olmp, nlmp, sizeof (Rt_map)); 254 free(nlmp); 255 nlmp = olmp; 256 olmp = 0; 257 258 /* 259 * Now that we've allocated our permanent Rt_map structure, expand the 260 * PATHNAME() and insert it into the FullpathNode AVL tree 261 */ 262 if (FLAGS1(nlmp) & FL1_RT_RELATIVE) 263 (void) fullpath(nlmp, 0); 264 if (fpavl_insert(lml, nlmp, PATHNAME(nlmp), 0) == 0) 265 return (0); 266 267 /* 268 * If we're being audited tell the audit library of the file we've just 269 * opened. 270 */ 271 if ((lml->lm_tflags | FLAGS1(nlmp)) & LML_TFLG_AUD_MASK) { 272 if (audit_objopen(lmp, lmp) == 0) 273 return (0); 274 } 275 return (nlmp); 276 } 277