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 /* 42 * Object representing a file which has been loaded by the linker. 43 */ 44 typedef struct linker_file* linker_file_t; 45 typedef TAILQ_HEAD(, linker_file) linker_file_list_t; 46 47 typedef caddr_t linker_sym_t; /* opaque symbol */ 48 typedef c_caddr_t c_linker_sym_t; /* const opaque symbol */ 49 typedef int (*linker_function_name_callback_t)(const char *, void *); 50 51 /* 52 * expanded out linker_sym_t 53 */ 54 typedef struct linker_symval { 55 const char* name; 56 caddr_t value; 57 size_t size; 58 } linker_symval_t; 59 60 struct common_symbol { 61 STAILQ_ENTRY(common_symbol) link; 62 char* name; 63 caddr_t address; 64 }; 65 66 struct linker_file { 67 KOBJ_FIELDS; 68 int refs; /* reference count */ 69 int userrefs; /* kldload(2) count */ 70 int flags; 71 #define LINKER_FILE_LINKED 0x1 /* file has been fully linked */ 72 TAILQ_ENTRY(linker_file) link; /* list of all loaded files */ 73 char* filename; /* file which was loaded */ 74 int id; /* unique id */ 75 caddr_t address; /* load address */ 76 size_t size; /* size of file */ 77 int ndeps; /* number of dependancies */ 78 linker_file_t* deps; /* list of dependancies */ 79 STAILQ_HEAD(, common_symbol) common; /* list of common symbols */ 80 TAILQ_HEAD(, module) modules; /* modules in this file */ 81 TAILQ_ENTRY(linker_file) loaded; /* preload dependency support */ 82 }; 83 84 /* 85 * Object implementing a class of file (a.out, elf, etc.) 86 */ 87 typedef struct linker_class *linker_class_t; 88 typedef TAILQ_HEAD(, linker_class) linker_class_list_t; 89 90 struct linker_class { 91 KOBJ_CLASS_FIELDS; 92 TAILQ_ENTRY(linker_class) link; /* list of all file classes */ 93 }; 94 95 /* 96 * The "file" for the kernel. 97 */ 98 extern linker_file_t linker_kernel_file; 99 100 /* 101 * Add a new file class to the linker. 102 */ 103 int linker_add_class(linker_class_t _cls); 104 105 /* 106 * Load a file, trying each file class until one succeeds. 107 */ 108 int linker_load_file(const char* _filename, linker_file_t* _result); 109 110 /* 111 * Obtain a reference to a module, loading it if required. 112 */ 113 int linker_reference_module(const char* _modname, linker_file_t* _result); 114 115 /* 116 * Find a currently loaded file given its filename. 117 */ 118 linker_file_t linker_find_file_by_name(const char* _filename); 119 120 /* 121 * Find a currently loaded file given its file id. 122 */ 123 linker_file_t linker_find_file_by_id(int _fileid); 124 125 /* 126 * Called from a class handler when a file is laoded. 127 */ 128 linker_file_t linker_make_file(const char* _filename, linker_class_t _cls); 129 130 /* 131 * Unload a file, freeing up memory. 132 */ 133 int linker_file_unload(linker_file_t _file); 134 135 /* 136 * Add a dependancy to a file. 137 */ 138 int linker_file_add_dependancy(linker_file_t _file, linker_file_t _dep); 139 140 /* 141 * Lookup a symbol in a file. If deps is TRUE, look in dependancies 142 * if not found in file. 143 */ 144 caddr_t linker_file_lookup_symbol(linker_file_t _file, const char* _name, 145 int _deps); 146 147 /* 148 * Lookup a linker set in a file. Return pointers to the first entry, 149 * last + 1, and count of entries. Use: for (p = start; p < stop; p++) {} 150 * void *start is really: "struct yoursetmember ***start;" 151 */ 152 int linker_file_lookup_set(linker_file_t _file, const char *_name, 153 void *_start, void *_stop, int *_count); 154 155 /* 156 * This routine is responsible for finding dependencies of userland 157 * initiated kldload(2)'s of files. 158 */ 159 int linker_load_dependancies(linker_file_t _lf); 160 161 /* 162 * DDB Helpers, tuned specifically for ddb/db_kld.c 163 */ 164 int linker_ddb_lookup(const char *_symstr, c_linker_sym_t *_sym); 165 int linker_ddb_search_symbol(caddr_t _value, c_linker_sym_t *_sym, 166 long *_diffp); 167 int linker_ddb_symbol_values(c_linker_sym_t _sym, linker_symval_t *_symval); 168 169 170 #endif /* _KERNEL */ 171 172 /* 173 * Module information subtypes 174 */ 175 #define MODINFO_END 0x0000 /* End of list */ 176 #define MODINFO_NAME 0x0001 /* Name of module (string) */ 177 #define MODINFO_TYPE 0x0002 /* Type of module (string) */ 178 #define MODINFO_ADDR 0x0003 /* Loaded address */ 179 #define MODINFO_SIZE 0x0004 /* Size of module */ 180 #define MODINFO_EMPTY 0x0005 /* Has been deleted */ 181 #define MODINFO_ARGS 0x0006 /* Parameters string */ 182 #define MODINFO_METADATA 0x8000 /* Module-specfic */ 183 184 #define MODINFOMD_AOUTEXEC 0x0001 /* a.out exec header */ 185 #define MODINFOMD_ELFHDR 0x0002 /* ELF header */ 186 #define MODINFOMD_SSYM 0x0003 /* start of symbols */ 187 #define MODINFOMD_ESYM 0x0004 /* end of symbols */ 188 #define MODINFOMD_DYNAMIC 0x0005 /* _DYNAMIC pointer */ 189 #define MODINFOMD_NOCOPY 0x8000 /* don't copy this metadata to the kernel */ 190 191 #define MODINFOMD_DEPLIST (0x4001 | MODINFOMD_NOCOPY) /* depends on */ 192 193 #define LINKER_HINTS_VERSION 1 /* linker.hints file version */ 194 195 #ifdef _KERNEL 196 197 /* 198 * Module lookup 199 */ 200 extern caddr_t preload_metadata; 201 extern caddr_t preload_search_by_name(const char *_name); 202 extern caddr_t preload_search_by_type(const char *_type); 203 extern caddr_t preload_search_next_name(caddr_t _base); 204 extern caddr_t preload_search_info(caddr_t _mod, int _inf); 205 extern void preload_delete_name(const char *_name); 206 extern void preload_bootstrap_relocate(vm_offset_t _offset); 207 208 #ifdef KLD_DEBUG 209 210 extern int kld_debug; 211 #define KLD_DEBUG_FILE 1 /* file load/unload */ 212 #define KLD_DEBUG_SYM 2 /* symbol lookup */ 213 214 #define KLD_DPF(cat, args) \ 215 do { \ 216 if (kld_debug & KLD_DEBUG_##cat) printf args; \ 217 } while (0) 218 219 #else 220 221 #define KLD_DPF(cat, args) 222 223 #endif 224 225 /* Support functions */ 226 int elf_reloc(linker_file_t _lf, const void *_rel, int _type, 227 const char *_sym); 228 /* values for type */ 229 #define ELF_RELOC_REL 1 230 #define ELF_RELOC_RELA 2 231 232 #endif /* _KERNEL */ 233 234 struct kld_file_stat { 235 int version; /* set to sizeof(linker_file_stat) */ 236 char name[MAXPATHLEN]; 237 int refs; 238 int id; 239 caddr_t address; /* load address */ 240 size_t size; /* size in bytes */ 241 }; 242 243 struct kld_sym_lookup { 244 int version; /* set to sizeof(struct kld_sym_lookup) */ 245 char *symname; /* Symbol name we are looking up */ 246 u_long symvalue; 247 size_t symsize; 248 }; 249 #define KLDSYM_LOOKUP 1 250 251 #ifndef _KERNEL 252 253 #include <sys/cdefs.h> 254 255 __BEGIN_DECLS 256 int kldload(const char* _file); 257 int kldunload(int _fileid); 258 int kldfind(const char* _file); 259 int kldnext(int _fileid); 260 int kldstat(int _fileid, struct kld_file_stat* _stat); 261 int kldfirstmod(int _fileid); 262 int kldsym(int _fileid, int _cmd, void *_data); 263 __END_DECLS 264 265 #endif 266 267 #endif /* !_SYS_LINKER_H_ */ 268