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 (((ofl->ofl_shdrsttab = st_new(0)) == 0) || 104 ((ofl->ofl_strtab = st_new(0)) == 0) || 105 ((ofl->ofl_dynstrtab = st_new(0)) == 0)) 106 return (0); 107 108 /* 109 * Assign the output file name to be the initial object that got us 110 * here. This name is being used for diagnostic purposes only as we 111 * don't actually generate an output file unless debugging is enabled. 112 */ 113 ofl->ofl_name = name; 114 ORIGNAME(olmp) = PATHNAME(olmp) = NAME(olmp) = (char *)name; 115 LIST(olmp) = lml; 116 117 lm_append(lml, lmco, olmp); 118 return (olmp); 119 } 120 121 /* 122 * Initial processing of a relocatable object. If this is the first object 123 * encountered we need to initialize some structures, then simply call the 124 * link-edit functionality to provide the initial processing of the file (ie. 125 * reads in sections and symbols, performs symbol resolution if more that one 126 * object file have been specified, and assigns input sections to output 127 * sections). 128 */ 129 Rt_map * 130 elf_obj_file(Lm_list *lml, Aliste lmco, const char *name, int fd) 131 { 132 Rej_desc rej; 133 134 /* 135 * If this is the first relocatable object (LD_PRELOAD could provide a 136 * list of objects), initialize an input file descriptor and a link map. 137 */ 138 if (!olmp) { 139 /* 140 * Load the link-editor library. 141 */ 142 if ((olmp = elf_obj_init(lml, lmco, name)) == 0) 143 return (0); 144 } 145 146 /* 147 * Proceed to process the input file. 148 */ 149 DBG_CALL(Dbg_util_nl(lml, DBG_NL_STD)); 150 if (ld_process_open(name, 0, fd, (Ofl_desc *)olmp->rt_priv, 151 NULL, &rej) == (Ifl_desc *)S_ERROR) 152 return (0); 153 return (olmp); 154 } 155 156 /* 157 * Finish relocatable object processing. Having already initially processed one 158 * or more objects, complete the generation of a shared object image by calling 159 * the appropriate link-edit functionality (refer to sgs/ld/common/main.c). 160 */ 161 Rt_map * 162 elf_obj_fini(Lm_list *lml, Rt_map *lmp) 163 { 164 Ofl_desc *ofl = (Ofl_desc *)lmp->rt_priv; 165 Rt_map *nlmp; 166 Addr etext; 167 Ehdr *ehdr; 168 Phdr *phdr; 169 Mmap *mmaps; 170 uint_t phnum, mmapcnt; 171 Lm_cntl *lmc; 172 173 DBG_CALL(Dbg_util_nl(lml, DBG_NL_STD)); 174 175 if (ld_reloc_init(ofl) == S_ERROR) 176 return (0); 177 if (ld_sym_validate(ofl) == S_ERROR) 178 return (0); 179 if (ld_make_sections(ofl) == S_ERROR) 180 return (0); 181 if (ld_create_outfile(ofl) == S_ERROR) 182 return (0); 183 if ((etext = ld_update_outfile(ofl)) == (Addr)S_ERROR) 184 return (0); 185 if (ld_reloc_process(ofl) == S_ERROR) 186 return (0); 187 188 /* 189 * At this point we have a memory image of the shared object. The link 190 * editor would normally simply write this to the required output file. 191 * If we're debugging generate a standard temporary output file. 192 */ 193 DBG_CALL(Dbg_file_output(ofl)); 194 195 /* 196 * Allocate a mapping array to retain mapped segment information. 197 */ 198 ehdr = ofl->ofl_nehdr; 199 phdr = ofl->ofl_phdr; 200 if ((mmaps = calloc(ehdr->e_phnum, sizeof (Mmap))) == 0) 201 return (0); 202 for (mmapcnt = 0, phnum = 0; phnum < ehdr->e_phnum; phnum++) { 203 if (phdr[phnum].p_type != PT_LOAD) 204 continue; 205 206 mmaps[mmapcnt].m_vaddr = (caddr_t) 207 (phdr[phnum].p_vaddr + (ulong_t)ehdr); 208 mmaps[mmapcnt].m_msize = phdr[phnum].p_memsz; 209 mmaps[mmapcnt].m_fsize = phdr[phnum].p_filesz; 210 mmaps[mmapcnt].m_perm = (PROT_READ | PROT_WRITE | PROT_EXEC); 211 mmapcnt++; 212 } 213 214 /* 215 * Generate a new link map representing the memory image created. 216 */ 217 if ((nlmp = elf_new_lm(lml, ofl->ofl_name, ofl->ofl_name, 218 ofl->ofl_osdynamic->os_outdata->d_buf, (ulong_t)ehdr, 219 (ulong_t)ehdr + etext, CNTL(olmp), (ulong_t)ofl->ofl_size, 220 0, 0, 0, mmaps, mmapcnt)) == 0) 221 return (0); 222 223 /* 224 * Remove this link map from the end of the link map list and copy its 225 * contents into the link map originally created for this file (we copy 226 * the contents rather than manipulate the link map pointers as parts 227 * of the dlopen code have remembered the original link map address). 228 */ 229 NEXT((Rt_map *)PREV(nlmp)) = 0; 230 /* LINTED */ 231 lmc = (Lm_cntl *)((char *)lml->lm_lists + CNTL(nlmp)); 232 lmc->lc_tail = (Rt_map *)PREV(nlmp); 233 if (CNTL(nlmp) == ALO_DATA) 234 lml->lm_tail = (Rt_map *)PREV(nlmp); 235 lml->lm_obj--; 236 237 PREV(nlmp) = PREV(olmp); 238 NEXT(nlmp) = NEXT(olmp); 239 HANDLES(nlmp) = HANDLES(olmp); 240 GROUPS(nlmp) = GROUPS(olmp); 241 STDEV(nlmp) = STDEV(olmp); 242 STINO(nlmp) = STINO(olmp); 243 244 FLAGS(nlmp) |= ((FLAGS(olmp) & ~FLG_RT_OBJECT) | FLG_RT_IMGALLOC); 245 FLAGS1(nlmp) |= FLAGS1(olmp); 246 MODE(nlmp) |= MODE(olmp); 247 248 NAME(nlmp) = NAME(olmp); 249 PATHNAME(nlmp) = PATHNAME(olmp); 250 ORIGNAME(nlmp) = ORIGNAME(olmp); 251 DIRSZ(nlmp) = DIRSZ(olmp); 252 253 ld_ofl_cleanup(ofl); 254 free(olmp->rt_priv); 255 (void) memcpy(olmp, nlmp, sizeof (Rt_map)); 256 free(nlmp); 257 nlmp = olmp; 258 olmp = 0; 259 260 /* 261 * Now that we've allocated our permanent Rt_map structure, expand the 262 * PATHNAME() and insert it into the FullpathNode AVL tree 263 */ 264 if (FLAGS1(nlmp) & FL1_RT_RELATIVE) 265 (void) fullpath(nlmp, 0); 266 if (fpavl_insert(lml, nlmp, PATHNAME(nlmp), 0) == 0) 267 return (0); 268 269 /* 270 * If we're being audited tell the audit library of the file we've just 271 * opened. 272 */ 273 if ((lml->lm_tflags | FLAGS1(nlmp)) & LML_TFLG_AUD_MASK) { 274 if (audit_objopen(lmp, lmp) == 0) 275 return (0); 276 } 277 return (nlmp); 278 } 279