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 struct common_symbol { 63 STAILQ_ENTRY(common_symbol) link; 64 char* name; 65 caddr_t address; 66 }; 67 68 struct linker_file { 69 KOBJ_FIELDS; 70 int refs; /* reference count */ 71 int userrefs; /* kldload(2) count */ 72 int flags; 73 #define LINKER_FILE_LINKED 0x1 /* file has been fully linked */ 74 TAILQ_ENTRY(linker_file) link; /* list of all loaded files */ 75 char* filename; /* file which was loaded */ 76 int id; /* unique id */ 77 caddr_t address; /* load address */ 78 size_t size; /* size of file */ 79 int ndeps; /* number of dependencies */ 80 linker_file_t* deps; /* list of dependencies */ 81 STAILQ_HEAD(, common_symbol) common; /* list of common symbols */ 82 TAILQ_HEAD(, module) modules; /* modules in this file */ 83 TAILQ_ENTRY(linker_file) loaded; /* preload dependency support */ 84 }; 85 86 /* 87 * Object implementing a class of file (a.out, elf, etc.) 88 */ 89 typedef struct linker_class *linker_class_t; 90 typedef TAILQ_HEAD(, linker_class) linker_class_list_t; 91 92 struct linker_class { 93 KOBJ_CLASS_FIELDS; 94 TAILQ_ENTRY(linker_class) link; /* list of all file classes */ 95 }; 96 97 /* 98 * The "file" for the kernel. 99 */ 100 extern linker_file_t linker_kernel_file; 101 102 /* 103 * Add a new file class to the linker. 104 */ 105 int linker_add_class(linker_class_t _cls); 106 107 /* 108 * Load a file, trying each file class until one succeeds. 109 */ 110 int linker_load_file(const char* _filename, linker_file_t* _result); 111 112 /* 113 * Obtain a reference to a module, loading it if required. 114 */ 115 int linker_reference_module(const char* _modname, struct mod_depend *_verinfo, 116 linker_file_t* _result); 117 118 /* 119 * Find a currently loaded file given its filename. 120 */ 121 linker_file_t linker_find_file_by_name(const char* _filename); 122 123 /* 124 * Find a currently loaded file given its file id. 125 */ 126 linker_file_t linker_find_file_by_id(int _fileid); 127 128 /* 129 * Called from a class handler when a file is laoded. 130 */ 131 linker_file_t linker_make_file(const char* _filename, linker_class_t _cls); 132 133 /* 134 * Unload a file, freeing up memory. 135 */ 136 int linker_file_unload(linker_file_t _file); 137 138 /* 139 * Add a dependency to a file. 140 */ 141 int linker_file_add_dependency(linker_file_t _file, linker_file_t _dep); 142 143 /* 144 * Lookup a symbol in a file. If deps is TRUE, look in dependencies 145 * if not found in file. 146 */ 147 caddr_t linker_file_lookup_symbol(linker_file_t _file, const char* _name, 148 int _deps); 149 150 /* 151 * Lookup a linker set in a file. Return pointers to the first entry, 152 * last + 1, and count of entries. Use: for (p = start; p < stop; p++) {} 153 * void *start is really: "struct yoursetmember ***start;" 154 */ 155 int linker_file_lookup_set(linker_file_t _file, const char *_name, 156 void *_start, void *_stop, int *_count); 157 158 /* 159 * This routine is responsible for finding dependencies of userland 160 * initiated kldload(2)'s of files. 161 */ 162 int linker_load_dependencies(linker_file_t _lf); 163 164 /* 165 * DDB Helpers, tuned specifically for ddb/db_kld.c 166 */ 167 int linker_ddb_lookup(const char *_symstr, c_linker_sym_t *_sym); 168 int linker_ddb_search_symbol(caddr_t _value, c_linker_sym_t *_sym, 169 long *_diffp); 170 int linker_ddb_symbol_values(c_linker_sym_t _sym, linker_symval_t *_symval); 171 172 173 #endif /* _KERNEL */ 174 175 /* 176 * Module information subtypes 177 */ 178 #define MODINFO_END 0x0000 /* End of list */ 179 #define MODINFO_NAME 0x0001 /* Name of module (string) */ 180 #define MODINFO_TYPE 0x0002 /* Type of module (string) */ 181 #define MODINFO_ADDR 0x0003 /* Loaded address */ 182 #define MODINFO_SIZE 0x0004 /* Size of module */ 183 #define MODINFO_EMPTY 0x0005 /* Has been deleted */ 184 #define MODINFO_ARGS 0x0006 /* Parameters string */ 185 #define MODINFO_METADATA 0x8000 /* Module-specfic */ 186 187 #define MODINFOMD_AOUTEXEC 0x0001 /* a.out exec header */ 188 #define MODINFOMD_ELFHDR 0x0002 /* ELF header */ 189 #define MODINFOMD_SSYM 0x0003 /* start of symbols */ 190 #define MODINFOMD_ESYM 0x0004 /* end of symbols */ 191 #define MODINFOMD_DYNAMIC 0x0005 /* _DYNAMIC pointer */ 192 #define MODINFOMD_NOCOPY 0x8000 /* don't copy this metadata to the kernel */ 193 194 #define MODINFOMD_DEPLIST (0x4001 | MODINFOMD_NOCOPY) /* depends on */ 195 196 #define LINKER_HINTS_VERSION 1 /* linker.hints file version */ 197 198 #ifdef _KERNEL 199 200 /* 201 * Module lookup 202 */ 203 extern caddr_t preload_metadata; 204 extern caddr_t preload_search_by_name(const char *_name); 205 extern caddr_t preload_search_by_type(const char *_type); 206 extern caddr_t preload_search_next_name(caddr_t _base); 207 extern caddr_t preload_search_info(caddr_t _mod, int _inf); 208 extern void preload_delete_name(const char *_name); 209 extern void preload_bootstrap_relocate(vm_offset_t _offset); 210 211 #ifdef KLD_DEBUG 212 213 extern int kld_debug; 214 #define KLD_DEBUG_FILE 1 /* file load/unload */ 215 #define KLD_DEBUG_SYM 2 /* symbol lookup */ 216 217 #define KLD_DPF(cat, args) \ 218 do { \ 219 if (kld_debug & KLD_DEBUG_##cat) printf args; \ 220 } while (0) 221 222 #else 223 224 #define KLD_DPF(cat, args) 225 226 #endif 227 228 /* Support functions */ 229 int elf_reloc(linker_file_t _lf, const void *_rel, int _type); 230 Elf_Addr elf_lookup(linker_file_t, Elf_Word, int); 231 232 /* values for type */ 233 #define ELF_RELOC_REL 1 234 #define ELF_RELOC_RELA 2 235 236 #endif /* _KERNEL */ 237 238 struct kld_file_stat { 239 int version; /* set to sizeof(linker_file_stat) */ 240 char name[MAXPATHLEN]; 241 int refs; 242 int id; 243 caddr_t address; /* load address */ 244 size_t size; /* size in bytes */ 245 }; 246 247 struct kld_sym_lookup { 248 int version; /* set to sizeof(struct kld_sym_lookup) */ 249 char *symname; /* Symbol name we are looking up */ 250 u_long symvalue; 251 size_t symsize; 252 }; 253 #define KLDSYM_LOOKUP 1 254 255 #ifndef _KERNEL 256 257 #include <sys/cdefs.h> 258 259 __BEGIN_DECLS 260 int kldload(const char* _file); 261 int kldunload(int _fileid); 262 int kldfind(const char* _file); 263 int kldnext(int _fileid); 264 int kldstat(int _fileid, struct kld_file_stat* _stat); 265 int kldfirstmod(int _fileid); 266 int kldsym(int _fileid, int _cmd, void *_data); 267 __END_DECLS 268 269 #endif 270 271 #endif /* !_SYS_LINKER_H_ */ 272