1 /*- 2 * Copyright (c) 1997-2000 Doug Rabson 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD$ 27 */ 28 29 #ifndef _SYS_LINKER_H_ 30 #define _SYS_LINKER_H_ 31 32 #ifdef _KERNEL 33 34 #include <machine/elf.h> 35 #include <sys/kobj.h> 36 37 #ifdef MALLOC_DECLARE 38 MALLOC_DECLARE(M_LINKER); 39 #endif 40 41 struct mod_depend; 42 43 /* 44 * Object representing a file which has been loaded by the linker. 45 */ 46 typedef struct linker_file* linker_file_t; 47 typedef TAILQ_HEAD(, linker_file) linker_file_list_t; 48 49 typedef caddr_t linker_sym_t; /* opaque symbol */ 50 typedef c_caddr_t c_linker_sym_t; /* const opaque symbol */ 51 typedef int (*linker_function_name_callback_t)(const char *, void *); 52 53 /* 54 * expanded out linker_sym_t 55 */ 56 typedef struct linker_symval { 57 const char* name; 58 caddr_t value; 59 size_t size; 60 } linker_symval_t; 61 62 typedef int (*linker_function_nameval_callback_t)(linker_file_t, int, linker_symval_t *, void *); 63 64 struct common_symbol { 65 STAILQ_ENTRY(common_symbol) link; 66 char* name; 67 caddr_t address; 68 }; 69 70 struct linker_file { 71 KOBJ_FIELDS; 72 int refs; /* reference count */ 73 int userrefs; /* kldload(2) count */ 74 int flags; 75 #define LINKER_FILE_LINKED 0x1 /* file has been fully linked */ 76 TAILQ_ENTRY(linker_file) link; /* list of all loaded files */ 77 char* filename; /* file which was loaded */ 78 char* pathname; /* file name with full path */ 79 int id; /* unique id */ 80 caddr_t address; /* load address */ 81 size_t size; /* size of file */ 82 int ndeps; /* number of dependencies */ 83 linker_file_t* deps; /* list of dependencies */ 84 STAILQ_HEAD(, common_symbol) common; /* list of common symbols */ 85 TAILQ_HEAD(, module) modules; /* modules in this file */ 86 TAILQ_ENTRY(linker_file) loaded; /* preload dependency support */ 87 int loadcnt; /* load counter value */ 88 89 /* 90 * Function Boundary Tracing (FBT) or Statically Defined Tracing (SDT) 91 * fields. 92 */ 93 int nenabled; /* number of enabled probes. */ 94 int fbt_nentries; /* number of fbt entries created. */ 95 }; 96 97 /* 98 * Object implementing a class of file (a.out, elf, etc.) 99 */ 100 typedef struct linker_class *linker_class_t; 101 typedef TAILQ_HEAD(, linker_class) linker_class_list_t; 102 103 struct linker_class { 104 KOBJ_CLASS_FIELDS; 105 TAILQ_ENTRY(linker_class) link; /* list of all file classes */ 106 }; 107 108 /* 109 * Function type used when iterating over the list of linker files. 110 */ 111 typedef int linker_predicate_t(linker_file_t, void *); 112 113 /* 114 * The "file" for the kernel. 115 */ 116 extern linker_file_t linker_kernel_file; 117 118 /* 119 * Obtain a reference to a module, loading it if required. 120 */ 121 int linker_reference_module(const char* _modname, struct mod_depend *_verinfo, 122 linker_file_t* _result); 123 124 /* 125 * Release a reference to a module, unloading it if there are no more 126 * references. Note that one should either provide a module name and 127 * optional version info or a linker file, but not both. 128 */ 129 int linker_release_module(const char *_modname, struct mod_depend *_verinfo, 130 linker_file_t _file); 131 132 /* 133 * Iterate over all of the currently loaded linker files calling the 134 * predicate function while the function returns 0. Returns the value 135 * returned by the last predicate function. 136 */ 137 int linker_file_foreach(linker_predicate_t *_predicate, void *_context); 138 139 /* 140 * Lookup a symbol in a file. If deps is TRUE, look in dependencies 141 * if not found in file. 142 */ 143 caddr_t linker_file_lookup_symbol(linker_file_t _file, const char* _name, 144 int _deps); 145 146 /* 147 * Lookup a linker set in a file. Return pointers to the first entry, 148 * last + 1, and count of entries. Use: for (p = start; p < stop; p++) {} 149 * void *start is really: "struct yoursetmember ***start;" 150 */ 151 int linker_file_lookup_set(linker_file_t _file, const char *_name, 152 void *_start, void *_stop, int *_count); 153 154 /* 155 * List all functions in a file. 156 */ 157 int linker_file_function_listall(linker_file_t, 158 linker_function_nameval_callback_t, void *); 159 160 /* 161 * Functions soley for use by the linker class handlers. 162 */ 163 int linker_add_class(linker_class_t _cls); 164 int linker_file_unload(linker_file_t _file, int flags); 165 int linker_load_dependencies(linker_file_t _lf); 166 linker_file_t linker_make_file(const char* _filename, linker_class_t _cls); 167 168 /* 169 * DDB Helpers, tuned specifically for ddb/db_kld.c 170 */ 171 int linker_ddb_lookup(const char *_symstr, c_linker_sym_t *_sym); 172 int linker_ddb_search_symbol(caddr_t _value, c_linker_sym_t *_sym, 173 long *_diffp); 174 int linker_ddb_symbol_values(c_linker_sym_t _sym, linker_symval_t *_symval); 175 int linker_ddb_search_symbol_name(caddr_t value, char *buf, u_int buflen, 176 long *offset); 177 178 /* 179 * stack(9) helper for situations where kernel locking is required. 180 */ 181 int linker_search_symbol_name(caddr_t value, char *buf, u_int buflen, 182 long *offset); 183 184 185 /* HWPMC helper */ 186 void *linker_hwpmc_list_objects(void); 187 188 #endif /* _KERNEL */ 189 190 /* 191 * Module information subtypes 192 */ 193 #define MODINFO_END 0x0000 /* End of list */ 194 #define MODINFO_NAME 0x0001 /* Name of module (string) */ 195 #define MODINFO_TYPE 0x0002 /* Type of module (string) */ 196 #define MODINFO_ADDR 0x0003 /* Loaded address */ 197 #define MODINFO_SIZE 0x0004 /* Size of module */ 198 #define MODINFO_EMPTY 0x0005 /* Has been deleted */ 199 #define MODINFO_ARGS 0x0006 /* Parameters string */ 200 #define MODINFO_METADATA 0x8000 /* Module-specfic */ 201 202 #define MODINFOMD_AOUTEXEC 0x0001 /* a.out exec header */ 203 #define MODINFOMD_ELFHDR 0x0002 /* ELF header */ 204 #define MODINFOMD_SSYM 0x0003 /* start of symbols */ 205 #define MODINFOMD_ESYM 0x0004 /* end of symbols */ 206 #define MODINFOMD_DYNAMIC 0x0005 /* _DYNAMIC pointer */ 207 /* These values are MD on these two platforms */ 208 #if !defined(__sparc64__) && !defined(__powerpc__) 209 #define MODINFOMD_ENVP 0x0006 /* envp[] */ 210 #define MODINFOMD_HOWTO 0x0007 /* boothowto */ 211 #define MODINFOMD_KERNEND 0x0008 /* kernend */ 212 #endif 213 #define MODINFOMD_SHDR 0x0009 /* section header table */ 214 #define MODINFOMD_NOCOPY 0x8000 /* don't copy this metadata to the kernel */ 215 216 #define MODINFOMD_DEPLIST (0x4001 | MODINFOMD_NOCOPY) /* depends on */ 217 218 #ifdef _KERNEL 219 #define MD_FETCH(mdp, info, type) ({ \ 220 type *__p; \ 221 __p = (type *)preload_search_info((mdp), MODINFO_METADATA | (info)); \ 222 __p ? *__p : 0; \ 223 }) 224 #endif 225 226 #define LINKER_HINTS_VERSION 1 /* linker.hints file version */ 227 228 #ifdef _KERNEL 229 230 /* 231 * Module lookup 232 */ 233 extern vm_offset_t preload_addr_relocate; 234 extern caddr_t preload_metadata; 235 236 extern void * preload_fetch_addr(caddr_t _mod); 237 extern size_t preload_fetch_size(caddr_t _mod); 238 extern caddr_t preload_search_by_name(const char *_name); 239 extern caddr_t preload_search_by_type(const char *_type); 240 extern caddr_t preload_search_next_name(caddr_t _base); 241 extern caddr_t preload_search_info(caddr_t _mod, int _inf); 242 extern void preload_delete_name(const char *_name); 243 extern void preload_bootstrap_relocate(vm_offset_t _offset); 244 245 #ifdef KLD_DEBUG 246 247 extern int kld_debug; 248 #define KLD_DEBUG_FILE 1 /* file load/unload */ 249 #define KLD_DEBUG_SYM 2 /* symbol lookup */ 250 251 #define KLD_DPF(cat, args) \ 252 do { \ 253 if (kld_debug & KLD_DEBUG_##cat) printf args; \ 254 } while (0) 255 256 #else 257 258 #define KLD_DPF(cat, args) 259 260 #endif 261 262 typedef Elf_Addr elf_lookup_fn(linker_file_t, Elf_Size, int); 263 264 /* Support functions */ 265 int elf_reloc(linker_file_t _lf, Elf_Addr base, const void *_rel, int _type, elf_lookup_fn _lu); 266 int elf_reloc_local(linker_file_t _lf, Elf_Addr base, const void *_rel, int _type, elf_lookup_fn _lu); 267 Elf_Addr elf_relocaddr(linker_file_t _lf, Elf_Addr addr); 268 const Elf_Sym *elf_get_sym(linker_file_t _lf, Elf_Size _symidx); 269 const char *elf_get_symname(linker_file_t _lf, Elf_Size _symidx); 270 271 typedef struct linker_ctf { 272 const uint8_t *ctftab; /* Decompressed CTF data. */ 273 int ctfcnt; /* Number of CTF data bytes. */ 274 const Elf_Sym *symtab; /* Ptr to the symbol table. */ 275 int nsym; /* Number of symbols. */ 276 const char *strtab; /* Ptr to the string table. */ 277 int strcnt; /* Number of string bytes. */ 278 uint32_t **ctfoffp; /* Ptr to array of obj/fnc offsets. */ 279 uint32_t **typoffp; /* Ptr to array of type offsets. */ 280 long *typlenp; /* Ptr to number of type data entries. */ 281 } linker_ctf_t; 282 283 int linker_ctf_get(linker_file_t, linker_ctf_t *); 284 285 int elf_cpu_load_file(linker_file_t); 286 int elf_cpu_unload_file(linker_file_t); 287 288 /* values for type */ 289 #define ELF_RELOC_REL 1 290 #define ELF_RELOC_RELA 2 291 292 /* 293 * This is version 1 of the KLD file status structure. It is identified 294 * by its _size_ in the version field. 295 */ 296 struct kld_file_stat_1 { 297 int version; /* set to sizeof(struct kld_file_stat_1) */ 298 char name[MAXPATHLEN]; 299 int refs; 300 int id; 301 caddr_t address; /* load address */ 302 size_t size; /* size in bytes */ 303 }; 304 #endif /* _KERNEL */ 305 306 struct kld_file_stat { 307 int version; /* set to sizeof(struct kld_file_stat) */ 308 char name[MAXPATHLEN]; 309 int refs; 310 int id; 311 caddr_t address; /* load address */ 312 size_t size; /* size in bytes */ 313 char pathname[MAXPATHLEN]; 314 }; 315 316 struct kld_sym_lookup { 317 int version; /* set to sizeof(struct kld_sym_lookup) */ 318 char *symname; /* Symbol name we are looking up */ 319 u_long symvalue; 320 size_t symsize; 321 }; 322 #define KLDSYM_LOOKUP 1 323 324 /* 325 * Flags for kldunloadf() and linker_file_unload() 326 */ 327 #define LINKER_UNLOAD_NORMAL 0 328 #define LINKER_UNLOAD_FORCE 1 329 330 #ifndef _KERNEL 331 332 #include <sys/cdefs.h> 333 334 __BEGIN_DECLS 335 int kldload(const char* _file); 336 int kldunload(int _fileid); 337 int kldunloadf(int _fileid, int flags); 338 int kldfind(const char* _file); 339 int kldnext(int _fileid); 340 int kldstat(int _fileid, struct kld_file_stat* _stat); 341 int kldfirstmod(int _fileid); 342 int kldsym(int _fileid, int _cmd, void *_data); 343 __END_DECLS 344 345 #endif 346 347 #endif /* !_SYS_LINKER_H_ */ 348