1 /* Internal definitions for libdwfl.
2 Copyright (C) 2005, 2006, 2007, 2008 Red Hat, Inc.
3 This file is part of Red Hat elfutils.
4
5 Red Hat elfutils is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by the
7 Free Software Foundation; version 2 of the License.
8
9 Red Hat elfutils is distributed in the hope that it will be useful, but
10 WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 General Public License for more details.
13
14 You should have received a copy of the GNU General Public License along
15 with Red Hat elfutils; if not, write to the Free Software Foundation,
16 Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.
17
18 In addition, as a special exception, Red Hat, Inc. gives You the
19 additional right to link the code of Red Hat elfutils with code licensed
20 under any Open Source Initiative certified open source license
21 (http://www.opensource.org/licenses/index.php) which requires the
22 distribution of source code with any binary distribution and to
23 distribute linked combinations of the two. Non-GPL Code permitted under
24 this exception must only link to the code of Red Hat elfutils through
25 those well defined interfaces identified in the file named EXCEPTION
26 found in the source code files (the "Approved Interfaces"). The files
27 of Non-GPL Code may instantiate templates or use macros or inline
28 functions from the Approved Interfaces without causing the resulting
29 work to be covered by the GNU General Public License. Only Red Hat,
30 Inc. may make changes or additions to the list of Approved Interfaces.
31 Red Hat's grant of this exception is conditioned upon your not adding
32 any new exceptions. If you wish to add a new Approved Interface or
33 exception, please contact Red Hat. You must obey the GNU General Public
34 License in all respects for all of the Red Hat elfutils code and other
35 code used in conjunction with Red Hat elfutils except the Non-GPL Code
36 covered by this exception. If you modify this file, you may extend this
37 exception to your version of the file, but you are not obligated to do
38 so. If you do not wish to provide this exception without modification,
39 you must delete this exception statement from your version and license
40 this file solely under the GPL without exception.
41
42 Red Hat elfutils is an included package of the Open Invention Network.
43 An included package of the Open Invention Network is a package for which
44 Open Invention Network licensees cross-license their patents. No patent
45 license is granted, either expressly or impliedly, by designation as an
46 included package. Should you wish to participate in the Open Invention
47 Network licensing program, please visit www.openinventionnetwork.com
48 <http://www.openinventionnetwork.com>. */
49
50 #ifndef _LIBDWFLP_H
51 #define _LIBDWFLP_H 1
52
53 #ifndef PACKAGE_NAME
54 # include <config.h>
55 #endif
56 #include <libdwfl.h>
57 #include <libebl.h>
58 #include <assert.h>
59 #include <errno.h>
60 #include <stdbool.h>
61 #include <stdlib.h>
62 #include <string.h>
63
64 #include "../libdw/libdwP.h" /* We need its INTDECLs. */
65
66 /* gettext helper macros. */
67 #define _(Str) dgettext ("elfutils", Str)
68
69 #define DWFL_ERRORS \
70 DWFL_ERROR (NOERROR, N_("no error")) \
71 DWFL_ERROR (UNKNOWN_ERROR, N_("unknown error")) \
72 DWFL_ERROR (NOMEM, N_("out of memory")) \
73 DWFL_ERROR (ERRNO, N_("See errno")) \
74 DWFL_ERROR (LIBELF, N_("See elf_errno")) \
75 DWFL_ERROR (LIBDW, N_("See dwarf_errno")) \
76 DWFL_ERROR (LIBEBL, N_("See ebl_errno (XXX missing)")) \
77 DWFL_ERROR (UNKNOWN_MACHINE, N_("no support library found for machine")) \
78 DWFL_ERROR (NOREL, N_("Callbacks missing for ET_REL file")) \
79 DWFL_ERROR (BADRELTYPE, N_("Unsupported relocation type")) \
80 DWFL_ERROR (BADRELOFF, N_("r_offset is bogus")) \
81 DWFL_ERROR (BADSTROFF, N_("offset out of range")) \
82 DWFL_ERROR (RELUNDEF, N_("relocation refers to undefined symbol")) \
83 DWFL_ERROR (CB, N_("Callback returned failure")) \
84 DWFL_ERROR (NO_DWARF, N_("No DWARF information found")) \
85 DWFL_ERROR (NO_SYMTAB, N_("No symbol table found")) \
86 DWFL_ERROR (NO_PHDR, N_("No ELF program headers")) \
87 DWFL_ERROR (OVERLAP, N_("address range overlaps an existing module")) \
88 DWFL_ERROR (ADDR_OUTOFRANGE, N_("address out of range")) \
89 DWFL_ERROR (NO_MATCH, N_("no matching address range")) \
90 DWFL_ERROR (TRUNCATED, N_("image truncated")) \
91 DWFL_ERROR (ALREADY_ELF, N_("ELF file opened")) \
92 DWFL_ERROR (BADELF, N_("not a valid ELF file")) \
93 DWFL_ERROR (WEIRD_TYPE, N_("cannot handle DWARF type description"))
94
95 #define DWFL_ERROR(name, text) DWFL_E_##name,
96 typedef enum { DWFL_ERRORS DWFL_E_NUM } Dwfl_Error;
97 #undef DWFL_ERROR
98
99 #define OTHER_ERROR(name) ((unsigned int) DWFL_E_##name << 16)
100 #define DWFL_E(name, errno) (OTHER_ERROR (name) | (errno))
101
102 extern int __libdwfl_canon_error (Dwfl_Error) internal_function;
103 extern void __libdwfl_seterrno (Dwfl_Error) internal_function;
104
105 struct Dwfl
106 {
107 const Dwfl_Callbacks *callbacks;
108
109 Dwfl_Module *modulelist; /* List in order used by full traversals. */
110
111 GElf_Addr offline_next_address;
112
113 GElf_Addr segment_align; /* Smallest granularity of segments. */
114
115 /* Binary search table in three parallel malloc'd arrays. */
116 size_t lookup_elts; /* Elements in use. */
117 size_t lookup_alloc; /* Elements allococated. */
118 GElf_Addr *lookup_addr; /* Start address of segment. */
119 Dwfl_Module **lookup_module; /* Module associated with segment, or null. */
120 int *lookup_segndx; /* User segment index, or -1. */
121
122 /* Cache from last dwfl_report_segment call. */
123 const void *lookup_tail_ident;
124 GElf_Off lookup_tail_vaddr;
125 GElf_Off lookup_tail_offset;
126 int lookup_tail_ndx;
127 };
128
129 #define OFFLINE_REDZONE 0x10000
130
131 struct dwfl_file
132 {
133 char *name;
134 int fd;
135 bool valid; /* The build ID note has been matched. */
136 bool relocated; /* Partial relocation of all sections done. */
137
138 Elf *elf;
139 GElf_Addr bias; /* Actual load address - p_vaddr. */
140 };
141
142 struct Dwfl_Module
143 {
144 Dwfl *dwfl;
145 struct Dwfl_Module *next; /* Link on Dwfl.modulelist. */
146
147 void *userdata;
148
149 char *name; /* Iterator name for this module. */
150 GElf_Addr low_addr, high_addr;
151
152 void *build_id_bits; /* malloc'd copy of build ID bits. */
153 GElf_Addr build_id_vaddr; /* Address where they reside, 0 if unknown. */
154 int build_id_len; /* -1 for prior failure, 0 if unset. */
155
156 struct dwfl_file main, debug;
157 Ebl *ebl;
158 GElf_Half e_type; /* GElf_Ehdr.e_type cache. */
159 Dwfl_Error elferr; /* Previous failure to open main file. */
160
161 struct dwfl_relocation *reloc_info; /* Relocatable sections. */
162
163 struct dwfl_file *symfile; /* Either main or debug. */
164 Elf_Data *symdata; /* Data in the ELF symbol table section. */
165 size_t syments; /* sh_size / sh_entsize of that section. */
166 Elf_Data *symstrdata; /* Data for its string table. */
167 Elf_Data *symxndxdata; /* Data in the extended section index table. */
168 Dwfl_Error symerr; /* Previous failure to load symbols. */
169
170 Dwarf *dw; /* libdw handle for its debugging info. */
171 Dwfl_Error dwerr; /* Previous failure to load info. */
172
173 /* Known CU's in this module. */
174 struct dwfl_cu *first_cu, **cu;
175 unsigned int ncu;
176
177 void *lazy_cu_root; /* Table indexed by Dwarf_Off of CU. */
178 unsigned int lazycu; /* Possible users, deleted when none left. */
179
180 struct dwfl_arange *aranges; /* Mapping of addresses in module to CUs. */
181 unsigned int naranges;
182
183 int segment; /* Index of first segment table entry. */
184 bool gc; /* Mark/sweep flag. */
185 };
186
187
188
189 /* Information cached about each CU in Dwfl_Module.dw. */
190 struct dwfl_cu
191 {
192 /* This caches libdw information about the CU. It's also the
193 address passed back to users, so we take advantage of the
194 fact that it's placed first to cast back. */
195 Dwarf_Die die;
196
197 Dwfl_Module *mod; /* Pointer back to containing module. */
198
199 struct dwfl_cu *next; /* CU immediately following in the file. */
200
201 struct Dwfl_Lines *lines;
202 };
203
204 struct Dwfl_Lines
205 {
206 struct dwfl_cu *cu;
207
208 /* This is what the opaque Dwfl_Line * pointers we pass to users are.
209 We need to recover pointers to our struct dwfl_cu and a record in
210 libdw's Dwarf_Line table. To minimize the memory used in addition
211 to libdw's Dwarf_Lines buffer, we just point to our own index in
212 this table, and have one pointer back to the CU. The indices here
213 match those in libdw's Dwarf_CU.lines->info table. */
214 struct Dwfl_Line
215 {
216 unsigned int idx; /* My index in the dwfl_cu.lines table. */
217 } idx[0];
218 };
219
220 static inline struct dwfl_cu *
dwfl_linecu_inline(const Dwfl_Line * line)221 dwfl_linecu_inline (const Dwfl_Line *line)
222 {
223 const struct Dwfl_Lines *lines = ((const void *) line
224 - offsetof (struct Dwfl_Lines,
225 idx[line->idx]));
226 return lines->cu;
227 }
228 #define dwfl_linecu dwfl_linecu_inline
229
230 /* This describes a contiguous address range that lies in a single CU.
231 We condense runs of Dwarf_Arange entries for the same CU into this. */
232 struct dwfl_arange
233 {
234 struct dwfl_cu *cu;
235 size_t arange; /* Index in Dwarf_Aranges. */
236 };
237
238
239
240 extern void __libdwfl_module_free (Dwfl_Module *mod) internal_function;
241
242
243 /* Process relocations in debugging sections in an ET_REL file.
244 FILE must be opened with ELF_C_READ_MMAP_PRIVATE or ELF_C_READ,
245 to make it possible to relocate the data in place (or ELF_C_RDWR or
246 ELF_C_RDWR_MMAP if you intend to modify the Elf file on disk). After
247 this, dwarf_begin_elf on FILE will read the relocated data.
248
249 When DEBUG is false, apply partial relocation to all sections. */
250 extern Dwfl_Error __libdwfl_relocate (Dwfl_Module *mod, Elf *file, bool debug)
251 internal_function;
252
253 /* Process (simple) relocations in arbitrary section TSCN of an ET_REL file.
254 RELOCSCN is SHT_REL or SHT_RELA and TSCN is its sh_info target section. */
255 extern Dwfl_Error __libdwfl_relocate_section (Dwfl_Module *mod, Elf *relocated,
256 Elf_Scn *relocscn, Elf_Scn *tscn,
257 bool partial)
258 internal_function;
259
260 /* Adjust *VALUE from section-relative to absolute.
261 MOD->dwfl->callbacks->section_address is called to determine the actual
262 address of a loaded section. */
263 extern Dwfl_Error __libdwfl_relocate_value (Dwfl_Module *mod, Elf *elf,
264 size_t *shstrndx_cache,
265 Elf32_Word shndx,
266 GElf_Addr *value)
267 internal_function;
268
269
270 /* Ensure that MOD->ebl is set up. */
271 extern Dwfl_Error __libdwfl_module_getebl (Dwfl_Module *mod) internal_function;
272
273 /* Iterate through all the CU's in the module. Start by passing a null
274 LASTCU, and then pass the last *CU returned. Success return with null
275 *CU no more CUs. */
276 extern Dwfl_Error __libdwfl_nextcu (Dwfl_Module *mod, struct dwfl_cu *lastcu,
277 struct dwfl_cu **cu) internal_function;
278
279 /* Find the CU by address. */
280 extern Dwfl_Error __libdwfl_addrcu (Dwfl_Module *mod, Dwarf_Addr addr,
281 struct dwfl_cu **cu) internal_function;
282
283 /* Ensure that CU->lines (and CU->cu->lines) is set up. */
284 extern Dwfl_Error __libdwfl_cu_getsrclines (struct dwfl_cu *cu)
285 internal_function;
286
287 /* Look in ELF for an NT_GNU_BUILD_ID note. If SET is true, store it
288 in MOD and return its length. If SET is false, instead compare it
289 to that stored in MOD and return 2 if they match, 1 if they do not.
290 Returns -1 for errors, 0 if no note is found. */
291 extern int __libdwfl_find_build_id (Dwfl_Module *mod, bool set, Elf *elf)
292 internal_function;
293
294 /* Open a main or debuginfo file by its build ID, returns the fd. */
295 extern int __libdwfl_open_by_build_id (Dwfl_Module *mod, bool debug,
296 char **file_name) internal_function;
297
298 extern uint32_t __libdwfl_crc32 (uint32_t crc, unsigned char *buf, size_t len)
299 attribute_hidden;
300 extern int __libdwfl_crc32_file (int fd, uint32_t *resp) attribute_hidden;
301
302
303 /* Meat of dwfl_report_elf, given elf_begin just called.
304 Consumes ELF on success, not on failure. */
305 extern Dwfl_Module *__libdwfl_report_elf (Dwfl *dwfl, const char *name,
306 const char *file_name, int fd,
307 Elf *elf, GElf_Addr base)
308 internal_function;
309
310 /* Meat of dwfl_report_offline. */
311 extern Dwfl_Module *__libdwfl_report_offline (Dwfl *dwfl, const char *name,
312 const char *file_name,
313 int fd, bool closefd,
314 int (*predicate) (const char *,
315 const char *))
316 internal_function;
317
318
319 /* These are working nicely for --core, but are not ready to be
320 exported interfaces quite yet. */
321
322 /* Type of callback function ...
323 */
324 typedef bool Dwfl_Memory_Callback (Dwfl *dwfl, int segndx,
325 void **buffer, size_t *buffer_available,
326 GElf_Addr vaddr, size_t minread, void *arg);
327
328 /* Type of callback function ...
329 */
330 typedef bool Dwfl_Module_Callback (Dwfl_Module *mod, void **userdata,
331 const char *name, Dwarf_Addr base,
332 void **buffer, size_t *buffer_available,
333 GElf_Off cost, GElf_Off worthwhile,
334 GElf_Off whole, GElf_Off contiguous,
335 void *arg, Elf **elfp);
336
337 /* ...
338 */
339 extern int dwfl_segment_report_module (Dwfl *dwfl, int ndx, const char *name,
340 Dwfl_Memory_Callback *memory_callback,
341 void *memory_callback_arg,
342 Dwfl_Module_Callback *read_eagerly,
343 void *read_eagerly_arg);
344
345 /* Report a module for entry in the dynamic linker's struct link_map list.
346 For each link_map entry, if an existing module resides at its address,
347 this just modifies that module's name and suggested file name. If
348 no such module exists, this calls dwfl_report_elf on the l_name string.
349
350 If AUXV is not null, it points to AUXV_SIZE bytes of auxiliary vector
351 data as contained in an NT_AUXV note or read from a /proc/pid/auxv
352 file. When this is available, it guides the search. If AUXV is null
353 or the memory it points to is not accessible, then this search can
354 only find where to begin if the correct executable file was
355 previously reported and preloaded as with dwfl_report_elf.
356
357 Returns the number of modules found, or -1 for errors. */
358 extern int dwfl_link_map_report (Dwfl *dwfl, const void *auxv, size_t auxv_size,
359 Dwfl_Memory_Callback *memory_callback,
360 void *memory_callback_arg);
361
362 /* Examine an ET_CORE file and report modules based on its contents. */
363 extern int dwfl_core_file_report (Dwfl *dwfl, Elf *elf, const GElf_Ehdr *ehdr);
364
365
366 /* Avoid PLT entries. */
367 INTDECL (dwfl_begin)
368 INTDECL (dwfl_errmsg)
369 INTDECL (dwfl_addrmodule)
370 INTDECL (dwfl_addrsegment)
371 INTDECL (dwfl_addrdwarf)
372 INTDECL (dwfl_addrdie)
373 INTDECL (dwfl_core_file_report)
374 INTDECL (dwfl_getmodules)
375 INTDECL (dwfl_module_addrdie)
376 INTDECL (dwfl_module_address_section)
377 INTDECL (dwfl_module_addrsym)
378 INTDECL (dwfl_module_build_id)
379 INTDECL (dwfl_module_getdwarf)
380 INTDECL (dwfl_module_getelf)
381 INTDECL (dwfl_module_getsym)
382 INTDECL (dwfl_module_getsymtab)
383 INTDECL (dwfl_module_getsrc)
384 INTDECL (dwfl_module_report_build_id)
385 INTDECL (dwfl_report_elf)
386 INTDECL (dwfl_report_begin)
387 INTDECL (dwfl_report_begin_add)
388 INTDECL (dwfl_report_module)
389 INTDECL (dwfl_report_segment)
390 INTDECL (dwfl_report_offline)
391 INTDECL (dwfl_report_end)
392 INTDECL (dwfl_build_id_find_elf)
393 INTDECL (dwfl_build_id_find_debuginfo)
394 INTDECL (dwfl_standard_find_debuginfo)
395 INTDECL (dwfl_link_map_report)
396 INTDECL (dwfl_linux_kernel_find_elf)
397 INTDECL (dwfl_linux_kernel_module_section_address)
398 INTDECL (dwfl_linux_proc_report)
399 INTDECL (dwfl_linux_proc_maps_report)
400 INTDECL (dwfl_linux_proc_find_elf)
401 INTDECL (dwfl_linux_kernel_report_kernel)
402 INTDECL (dwfl_linux_kernel_report_modules)
403 INTDECL (dwfl_linux_kernel_report_offline)
404 INTDECL (dwfl_offline_section_address)
405 INTDECL (dwfl_module_relocate_address)
406
407 /* Leading arguments standard to callbacks passed a Dwfl_Module. */
408 #define MODCB_ARGS(mod) (mod), &(mod)->userdata, (mod)->name, (mod)->low_addr
409 #define CBFAIL (errno ? DWFL_E (ERRNO, errno) : DWFL_E_CB);
410
411
412 /* The default used by dwfl_standard_find_debuginfo. */
413 #define DEFAULT_DEBUGINFO_PATH ":.debug:/usr/lib/debug"
414
415
416 #endif /* libdwflP.h */
417