1/*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 1997-2000 Doug Rabson 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 * $FreeBSD$ 29 */ 30 31#ifndef _SYS_LINKER_H_ 32#define _SYS_LINKER_H_ 33 34#ifdef _KERNEL 35 36#include <machine/elf.h> 37#include <sys/kobj.h> 38 39#ifdef MALLOC_DECLARE 40MALLOC_DECLARE(M_LINKER); 41#endif 42 43struct mod_depend; 44 45/* 46 * Object representing a file which has been loaded by the linker. 47 */ 48typedef struct linker_file* linker_file_t; 49typedef TAILQ_HEAD(, linker_file) linker_file_list_t; 50 51typedef caddr_t linker_sym_t; /* opaque symbol */ 52typedef c_caddr_t c_linker_sym_t; /* const opaque symbol */ 53typedef int (*linker_function_name_callback_t)(const char *, void *); 54 55/* 56 * expanded out linker_sym_t 57 */ 58typedef struct linker_symval { 59 const char* name; 60 caddr_t value; 61 size_t size; 62} linker_symval_t; 63 64typedef int (*linker_function_nameval_callback_t)(linker_file_t, int, linker_symval_t *, void *); 65 66struct common_symbol { 67 STAILQ_ENTRY(common_symbol) link; 68 char* name; 69 caddr_t address; 70}; 71 72struct linker_file { 73 KOBJ_FIELDS; 74 int refs; /* reference count */ 75 int userrefs; /* kldload(2) count */ 76 int flags; 77#define LINKER_FILE_LINKED 0x1 /* file has been fully linked */ 78#define LINKER_FILE_MODULES 0x2 /* file has >0 modules at preload */ 79 TAILQ_ENTRY(linker_file) link; /* list of all loaded files */ 80 char* filename; /* file which was loaded */ 81 char* pathname; /* file name with full path */ 82 int id; /* unique id */ 83 caddr_t address; /* load address */ 84 size_t size; /* size of file */ 85 caddr_t ctors_addr; /* address of .ctors */ 86 size_t ctors_size; /* size of .ctors */ 87 int ndeps; /* number of dependencies */ 88 linker_file_t* deps; /* list of dependencies */ 89 STAILQ_HEAD(, common_symbol) common; /* list of common symbols */ 90 TAILQ_HEAD(, module) modules; /* modules in this file */ 91 TAILQ_ENTRY(linker_file) loaded; /* preload dependency support */ 92 int loadcnt; /* load counter value */ 93 94 /* 95 * Function Boundary Tracing (FBT) or Statically Defined Tracing (SDT) 96 * fields. 97 */ 98 int nenabled; /* number of enabled probes. */ 99 int fbt_nentries; /* number of fbt entries created. */ 100 101#ifdef __arm__ 102 caddr_t exidx_addr; /* Unwind data index table start */ 103 size_t exidx_size; /* Unwind data index table size */ 104#endif 105}; 106 107/* 108 * Object implementing a class of file (a.out, elf, etc.) 109 */ 110typedef struct linker_class *linker_class_t; 111typedef TAILQ_HEAD(, linker_class) linker_class_list_t; 112 113struct linker_class { 114 KOBJ_CLASS_FIELDS; 115 TAILQ_ENTRY(linker_class) link; /* list of all file classes */ 116}; 117 118/* 119 * Function type used when iterating over the list of linker files. 120 */ 121typedef int linker_predicate_t(linker_file_t, void *); 122 123/* 124 * The "file" for the kernel. 125 */ 126extern linker_file_t linker_kernel_file; 127 128/* 129 * Obtain a reference to a module, loading it if required. 130 */ 131int linker_reference_module(const char* _modname, struct mod_depend *_verinfo, 132 linker_file_t* _result); 133 134/* 135 * Release a reference to a module, unloading it if there are no more 136 * references. Note that one should either provide a module name and 137 * optional version info or a linker file, but not both. 138 */ 139int linker_release_module(const char *_modname, struct mod_depend *_verinfo, 140 linker_file_t _file); 141 142/* 143 * Iterate over all of the currently loaded linker files calling the 144 * predicate function while the function returns 0. Returns the value 145 * returned by the last predicate function. 146 */ 147int linker_file_foreach(linker_predicate_t *_predicate, void *_context); 148 149/* 150 * Lookup a symbol in a file. If deps is TRUE, look in dependencies 151 * if not found in file. 152 */ 153caddr_t linker_file_lookup_symbol(linker_file_t _file, const char* _name, 154 int _deps); 155 156/* 157 * Lookup a linker set in a file. Return pointers to the first entry, 158 * last + 1, and count of entries. Use: for (p = start; p < stop; p++) {} 159 * void *start is really: "struct yoursetmember ***start;" 160 */ 161int linker_file_lookup_set(linker_file_t _file, const char *_name, 162 void *_start, void *_stop, int *_count); 163 164/* 165 * List all functions in a file. 166 */ 167int linker_file_function_listall(linker_file_t, 168 linker_function_nameval_callback_t, void *); 169 170/* 171 * Functions solely for use by the linker class handlers. 172 */ 173int linker_add_class(linker_class_t _cls); 174int linker_file_unload(linker_file_t _file, int flags); 175int linker_load_dependencies(linker_file_t _lf); 176linker_file_t linker_make_file(const char* _filename, linker_class_t _cls); 177 178/* 179 * DDB Helpers, tuned specifically for ddb/db_kld.c 180 */ 181int linker_ddb_lookup(const char *_symstr, c_linker_sym_t *_sym); 182int linker_ddb_search_symbol(caddr_t _value, c_linker_sym_t *_sym, 183 long *_diffp); 184int linker_ddb_symbol_values(c_linker_sym_t _sym, linker_symval_t *_symval); 185int linker_ddb_search_symbol_name(caddr_t value, char *buf, u_int buflen, 186 long *offset); 187 188/* 189 * stack(9) helper for situations where kernel locking is required. 190 */ 191int linker_search_symbol_name(caddr_t value, char *buf, u_int buflen, 192 long *offset); 193 194 195/* HWPMC helper */ 196void *linker_hwpmc_list_objects(void); 197 198#endif /* _KERNEL */ 199 200/* 201 * Module information subtypes 202 */ 203#define MODINFO_END 0x0000 /* End of list */ 204#define MODINFO_NAME 0x0001 /* Name of module (string) */ 205#define MODINFO_TYPE 0x0002 /* Type of module (string) */ 206#define MODINFO_ADDR 0x0003 /* Loaded address */ 207#define MODINFO_SIZE 0x0004 /* Size of module */ 208#define MODINFO_EMPTY 0x0005 /* Has been deleted */ 209#define MODINFO_ARGS 0x0006 /* Parameters string */ 210#define MODINFO_METADATA 0x8000 /* Module-specfic */ 211 212#define MODINFOMD_AOUTEXEC 0x0001 /* a.out exec header */ 213#define MODINFOMD_ELFHDR 0x0002 /* ELF header */ 214#define MODINFOMD_SSYM 0x0003 /* start of symbols */ 215#define MODINFOMD_ESYM 0x0004 /* end of symbols */ 216#define MODINFOMD_DYNAMIC 0x0005 /* _DYNAMIC pointer */ 217/* These values are MD on these two platforms */ 218#if !defined(__sparc64__) && !defined(__powerpc__) 219#define MODINFOMD_ENVP 0x0006 /* envp[] */ 220#define MODINFOMD_HOWTO 0x0007 /* boothowto */ 221#define MODINFOMD_KERNEND 0x0008 /* kernend */ 222#endif 223#define MODINFOMD_SHDR 0x0009 /* section header table */ 224#define MODINFOMD_CTORS_ADDR 0x000a /* address of .ctors */ 225#define MODINFOMD_CTORS_SIZE 0x000b /* size of .ctors */ 226#define MODINFOMD_FW_HANDLE 0x000c /* Firmware dependent handle */ 227#define MODINFOMD_KEYBUF 0x000d /* Crypto key intake buffer */ 228#define MODINFOMD_NOCOPY 0x8000 /* don't copy this metadata to the kernel */ 229 230#define MODINFOMD_DEPLIST (0x4001 | MODINFOMD_NOCOPY) /* depends on */ 231 232#ifdef _KERNEL 233#define MD_FETCH(mdp, info, type) ({ \ 234 type *__p; \ 235 __p = (type *)preload_search_info((mdp), MODINFO_METADATA | (info)); \ 236 __p ? *__p : 0; \ 237}) 238#endif 239 240#define LINKER_HINTS_VERSION 1 /* linker.hints file version */ 241#define LINKER_HINTS_MAX (1 << 20) /* Allow at most 1MB for linker.hints */ 242 243#ifdef _KERNEL 244 245/* 246 * Module lookup 247 */ 248extern vm_offset_t preload_addr_relocate; 249extern caddr_t preload_metadata; 250 251extern void * preload_fetch_addr(caddr_t _mod); 252extern size_t preload_fetch_size(caddr_t _mod); 253extern caddr_t preload_search_by_name(const char *_name); 254extern caddr_t preload_search_by_type(const char *_type); 255extern caddr_t preload_search_next_name(caddr_t _base); 256extern caddr_t preload_search_info(caddr_t _mod, int _inf); 257extern void preload_delete_name(const char *_name); 258extern void preload_bootstrap_relocate(vm_offset_t _offset); 259 260#ifdef KLD_DEBUG 261 262extern int kld_debug; 263#define KLD_DEBUG_FILE 1 /* file load/unload */ 264#define KLD_DEBUG_SYM 2 /* symbol lookup */ 265 266#define KLD_DPF(cat, args) \ 267 do { \ 268 if (kld_debug & KLD_DEBUG_##cat) printf args; \ 269 } while (0) 270 271#else 272 273#define KLD_DPF(cat, args) 274 275#endif 276 277typedef int elf_lookup_fn(linker_file_t, Elf_Size, int, Elf_Addr *); 278 279/* Support functions */ 280bool elf_is_ifunc_reloc(Elf_Size r_info); 281int elf_reloc(linker_file_t _lf, Elf_Addr base, const void *_rel, 282 int _type, elf_lookup_fn _lu); 283int elf_reloc_local(linker_file_t _lf, Elf_Addr base, const void *_rel, 284 int _type, elf_lookup_fn _lu); 285Elf_Addr elf_relocaddr(linker_file_t _lf, Elf_Addr addr); 286const Elf_Sym *elf_get_sym(linker_file_t _lf, Elf_Size _symidx); 287const char *elf_get_symname(linker_file_t _lf, Elf_Size _symidx); 288void link_elf_ireloc(caddr_t kmdp); 289 290typedef struct linker_ctf { 291 const uint8_t *ctftab; /* Decompressed CTF data. */ 292 int ctfcnt; /* Number of CTF data bytes. */ 293 const Elf_Sym *symtab; /* Ptr to the symbol table. */ 294 int nsym; /* Number of symbols. */ 295 const char *strtab; /* Ptr to the string table. */ 296 int strcnt; /* Number of string bytes. */ 297 uint32_t **ctfoffp; /* Ptr to array of obj/fnc offsets. */ 298 uint32_t **typoffp; /* Ptr to array of type offsets. */ 299 long *typlenp; /* Ptr to number of type data entries. */ 300} linker_ctf_t; 301 302int linker_ctf_get(linker_file_t, linker_ctf_t *); 303 304int elf_cpu_load_file(linker_file_t); 305int elf_cpu_unload_file(linker_file_t); 306 307/* values for type */ 308#define ELF_RELOC_REL 1 309#define ELF_RELOC_RELA 2 310 311/* 312 * This is version 1 of the KLD file status structure. It is identified 313 * by its _size_ in the version field. 314 */ 315struct kld_file_stat_1 { 316 int version; /* set to sizeof(struct kld_file_stat_1) */ 317 char name[MAXPATHLEN]; 318 int refs; 319 int id; 320 caddr_t address; /* load address */ 321 size_t size; /* size in bytes */ 322}; 323#endif /* _KERNEL */ 324 325struct kld_file_stat { 326 int version; /* set to sizeof(struct kld_file_stat) */ 327 char name[MAXPATHLEN]; 328 int refs; 329 int id; 330 caddr_t address; /* load address */ 331 size_t size; /* size in bytes */ 332 char pathname[MAXPATHLEN]; 333}; 334 335struct kld_sym_lookup { 336 int version; /* set to sizeof(struct kld_sym_lookup) */ 337 char *symname; /* Symbol name we are looking up */ 338 u_long symvalue; 339 size_t symsize; 340}; 341#define KLDSYM_LOOKUP 1 342 343/* 344 * Flags for kldunloadf() and linker_file_unload() 345 */ 346#define LINKER_UNLOAD_NORMAL 0 347#define LINKER_UNLOAD_FORCE 1 348 349#ifndef _KERNEL 350 351#include <sys/cdefs.h> 352 353__BEGIN_DECLS 354int kldload(const char* _file); 355int kldunload(int _fileid); 356int kldunloadf(int _fileid, int flags); 357int kldfind(const char* _file); 358int kldnext(int _fileid); 359int kldstat(int _fileid, struct kld_file_stat* _stat); 360int kldfirstmod(int _fileid); 361int kldsym(int _fileid, int _cmd, void *_data); 362__END_DECLS 363 364#endif 365 366#endif /* !_SYS_LINKER_H_ */ 367