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