]>
Commit | Line | Data |
---|---|---|
7389debf ILT |
1 | /* Support for 32-bit i386 NLM (NetWare Loadable Module) |
2 | Copyright (C) 1993 Free Software Foundation, Inc. | |
3 | ||
4 | This file is part of BFD, the Binary File Descriptor library. | |
5 | ||
6 | This program is free software; you can redistribute it and/or modify | |
7 | it under the terms of the GNU General Public License as published by | |
8 | the Free Software Foundation; either version 2 of the License, or | |
9 | (at your option) any later version. | |
10 | ||
11 | This program is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
17 | along with this program; if not, write to the Free Software | |
18 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ | |
19 | ||
20 | #include "bfd.h" | |
21 | #include "sysdep.h" | |
22 | #include "libbfd.h" | |
23 | ||
24 | #define ARCH_SIZE 32 | |
cdbfad1c ILT |
25 | |
26 | #include "nlm/i386-ext.h" | |
27 | #define Nlm_External_Fixed_Header Nlm32_i386_External_Fixed_Header | |
28 | ||
7389debf ILT |
29 | #include "libnlm.h" |
30 | ||
31 | static boolean nlm_i386_read_reloc | |
32 | PARAMS ((bfd *, nlmNAME(symbol_type) *, asection **, arelent *)); | |
cdbfad1c | 33 | static boolean nlm_i386_write_import |
7389debf ILT |
34 | PARAMS ((bfd *, asection *, arelent *)); |
35 | static boolean nlm_i386_mangle_relocs | |
36 | PARAMS ((bfd *, asection *, PTR, bfd_vma, bfd_size_type)); | |
cdbfad1c ILT |
37 | static boolean nlm_i386_read_import |
38 | PARAMS ((bfd *, nlmNAME(symbol_type) *)); | |
39 | static boolean nlm_i386_write_external | |
40 | PARAMS ((bfd *, bfd_size_type, asymbol *, struct reloc_and_sec *)); | |
7389debf ILT |
41 | |
42 | /* Adjust the reloc location by an absolute value. */ | |
43 | ||
44 | static reloc_howto_type nlm_i386_abs_howto = | |
45 | HOWTO (0, /* type */ | |
46 | 0, /* rightshift */ | |
47 | 2, /* size (0 = byte, 1 = short, 2 = long) */ | |
48 | 32, /* bitsize */ | |
49 | false, /* pc_relative */ | |
50 | 0, /* bitpos */ | |
51 | complain_overflow_bitfield, /* complain_on_overflow */ | |
52 | 0, /* special_function */ | |
53 | "32", /* name */ | |
54 | true, /* partial_inplace */ | |
55 | 0xffffffff, /* src_mask */ | |
56 | 0xffffffff, /* dst_mask */ | |
57 | false); /* pcrel_offset */ | |
58 | ||
59 | /* Adjust the reloc location by a PC relative displacement. */ | |
60 | ||
61 | static reloc_howto_type nlm_i386_pcrel_howto = | |
62 | HOWTO (1, /* type */ | |
63 | 0, /* rightshift */ | |
64 | 2, /* size (0 = byte, 1 = short, 2 = long) */ | |
65 | 32, /* bitsize */ | |
66 | true, /* pc_relative */ | |
67 | 0, /* bitpos */ | |
68 | complain_overflow_signed, /* complain_on_overflow */ | |
69 | 0, /* special_function */ | |
70 | "DISP32", /* name */ | |
71 | true, /* partial_inplace */ | |
72 | 0xffffffff, /* src_mask */ | |
73 | 0xffffffff, /* dst_mask */ | |
74 | true); /* pcrel_offset */ | |
75 | ||
76 | /* Read a NetWare i386 reloc. */ | |
77 | ||
78 | static boolean | |
79 | nlm_i386_read_reloc (abfd, sym, secp, rel) | |
80 | bfd *abfd; | |
81 | nlmNAME(symbol_type) *sym; | |
82 | asection **secp; | |
83 | arelent *rel; | |
84 | { | |
85 | bfd_byte temp[4]; | |
86 | bfd_vma val; | |
87 | const char *name; | |
88 | ||
89 | if (bfd_read (temp, sizeof (temp), 1, abfd) != sizeof (temp)) | |
90 | { | |
91 | bfd_error = system_call_error; | |
92 | return false; | |
93 | } | |
94 | ||
95 | val = bfd_get_32 (abfd, temp); | |
96 | ||
97 | /* The value is an offset into either the code or data segment. | |
98 | This is the location which needs to be adjusted. | |
99 | ||
100 | If this is a relocation fixup rather than an imported symbol (the | |
101 | sym argument is NULL) then the high bit is 0 if the location | |
102 | needs to be adjusted by the address of the data segment, or 1 if | |
103 | the location needs to be adjusted by the address of the code | |
104 | segment. If this is an imported symbol, then the high bit is 0 | |
105 | if the location is 0 if the location should be adjusted by the | |
106 | offset to the symbol, or 1 if the location should adjusted by the | |
107 | absolute value of the symbol. | |
108 | ||
109 | The second most significant bit is 0 if the value is an offset | |
110 | into the data segment, or 1 if the value is an offset into the | |
111 | code segment. | |
112 | ||
113 | All this translates fairly easily into a BFD reloc. */ | |
114 | ||
115 | if (sym == NULL) | |
116 | { | |
117 | if ((val & NLM_HIBIT) == 0) | |
118 | name = NLM_INITIALIZED_DATA_NAME; | |
119 | else | |
120 | { | |
121 | name = NLM_CODE_NAME; | |
122 | val &=~ NLM_HIBIT; | |
123 | } | |
124 | rel->sym_ptr_ptr = bfd_get_section_by_name (abfd, name)->symbol_ptr_ptr; | |
125 | rel->howto = &nlm_i386_abs_howto; | |
126 | } | |
127 | else | |
128 | { | |
129 | /* In this case we do not need to set the sym_ptr_ptr field. */ | |
130 | rel->sym_ptr_ptr = NULL; | |
131 | if ((val & NLM_HIBIT) == 0) | |
132 | rel->howto = &nlm_i386_pcrel_howto; | |
133 | else | |
134 | { | |
135 | rel->howto = &nlm_i386_abs_howto; | |
136 | val &=~ NLM_HIBIT; | |
137 | } | |
138 | } | |
139 | ||
140 | if ((val & (NLM_HIBIT >> 1)) == 0) | |
141 | *secp = bfd_get_section_by_name (abfd, NLM_INITIALIZED_DATA_NAME); | |
142 | else | |
143 | { | |
144 | *secp = bfd_get_section_by_name (abfd, NLM_CODE_NAME); | |
145 | val &=~ (NLM_HIBIT >> 1); | |
146 | } | |
147 | ||
148 | rel->address = val; | |
149 | rel->addend = 0; | |
150 | ||
151 | return true; | |
152 | } | |
153 | ||
154 | /* Write a NetWare i386 reloc. */ | |
155 | ||
156 | static boolean | |
cdbfad1c | 157 | nlm_i386_write_import (abfd, sec, rel) |
7389debf ILT |
158 | bfd *abfd; |
159 | asection *sec; | |
160 | arelent *rel; | |
161 | { | |
162 | asymbol *sym; | |
163 | bfd_vma val; | |
164 | bfd_byte temp[4]; | |
165 | ||
166 | /* NetWare only supports two kinds of relocs. We should check | |
167 | special_function here, as well, but at the moment coff-i386 | |
168 | relocs uses a special_function which does not affect what we do | |
169 | here. */ | |
170 | if (rel->addend != 0 | |
171 | || rel->howto == NULL | |
172 | || rel->howto->rightshift != 0 | |
173 | || rel->howto->size != 2 | |
174 | || rel->howto->bitsize != 32 | |
175 | || rel->howto->bitpos != 0 | |
7389debf ILT |
176 | || rel->howto->src_mask != 0xffffffff |
177 | || rel->howto->dst_mask != 0xffffffff) | |
178 | { | |
179 | bfd_error = invalid_operation; | |
180 | return false; | |
181 | } | |
182 | ||
183 | sym = *rel->sym_ptr_ptr; | |
184 | ||
185 | /* The value we write out is the offset into the appropriate | |
186 | segment. This offset is the section vma, adjusted by the vma of | |
187 | the lowest section in that segment, plus the address of the | |
188 | relocation. */ | |
189 | val = bfd_get_section_vma (abfd, sec) + rel->address; | |
190 | ||
191 | /* The second most significant bit is 0 if the value is an offset | |
192 | into the data segment, or 1 if the value is an offset into the | |
193 | code segment. */ | |
194 | if (bfd_get_section_flags (abfd, sec) & SEC_CODE) | |
195 | { | |
196 | val -= nlm_get_text_low (abfd); | |
197 | val |= NLM_HIBIT >> 1; | |
198 | } | |
199 | else | |
200 | val -= nlm_get_data_low (abfd); | |
201 | ||
202 | if (bfd_get_section (sym) != &bfd_und_section) | |
203 | { | |
204 | /* NetWare only supports absolute internal relocs. */ | |
205 | if (rel->howto->pc_relative) | |
206 | { | |
207 | bfd_error = invalid_operation; | |
208 | return false; | |
209 | } | |
210 | ||
211 | /* The high bit is 1 if the reloc is against the code section, 0 | |
212 | if against the data section. */ | |
213 | if (bfd_get_section_flags (abfd, bfd_get_section (sym)) & SEC_CODE) | |
214 | val |= NLM_HIBIT; | |
215 | } | |
216 | else | |
217 | { | |
218 | /* The high bit is 1 if this is an absolute reloc, 0 if it is PC | |
219 | relative. */ | |
220 | if (! rel->howto->pc_relative) | |
221 | val |= NLM_HIBIT; | |
222 | else | |
223 | { | |
224 | /* PC relative relocs on NetWare must be pcrel_offset. */ | |
225 | if (! rel->howto->pcrel_offset) | |
226 | { | |
227 | bfd_error = invalid_operation; | |
228 | return false; | |
229 | } | |
230 | } | |
231 | } | |
232 | ||
233 | bfd_put_32 (abfd, val, temp); | |
234 | if (bfd_write (temp, sizeof (temp), 1, abfd) != sizeof (temp)) | |
235 | { | |
236 | bfd_error = system_call_error; | |
237 | return false; | |
238 | } | |
239 | ||
240 | return true; | |
241 | } | |
242 | ||
243 | /* I want to be able to use objcopy to turn a i386 a.out or COFF file | |
244 | into a NetWare i386 module. That means that the relocs from the | |
245 | source file have to be mapped into relocs that apply to the target | |
246 | file. This function is called by nlm_set_section_contents to give | |
247 | it a chance to rework the relocs. | |
248 | ||
249 | This is actually a fairly general concept. However, this is not a | |
250 | general implementation. */ | |
251 | ||
252 | static boolean | |
253 | nlm_i386_mangle_relocs (abfd, sec, data, offset, count) | |
254 | bfd *abfd; | |
255 | asection *sec; | |
256 | PTR data; | |
257 | bfd_vma offset; | |
258 | bfd_size_type count; | |
259 | { | |
260 | arelent **rel_ptr_ptr, **rel_end; | |
261 | ||
262 | rel_ptr_ptr = sec->orelocation; | |
263 | rel_end = rel_ptr_ptr + sec->reloc_count; | |
264 | for (; rel_ptr_ptr < rel_end; rel_ptr_ptr++) | |
265 | { | |
266 | arelent *rel; | |
267 | asymbol *sym; | |
268 | bfd_vma addend; | |
269 | ||
270 | rel = *rel_ptr_ptr; | |
271 | sym = *rel->sym_ptr_ptr; | |
272 | ||
273 | /* Note that no serious harm will ensue if we fail to change a | |
cdbfad1c | 274 | reloc. We will wind up failing in nlm_i386_write_import. */ |
7389debf ILT |
275 | |
276 | /* Make sure this reloc is within the data we have. We only 4 | |
277 | byte relocs here, so we insist on having 4 bytes. */ | |
278 | if (rel->address < offset | |
279 | || rel->address + 4 > offset + count) | |
280 | continue; | |
281 | ||
282 | /* NetWare doesn't support reloc addends, so we get rid of them | |
283 | here by simply adding them into the object data. We handle | |
284 | the symbol value, if any, the same way. */ | |
285 | addend = rel->addend + sym->value; | |
286 | ||
287 | /* The value of a symbol is the offset into the section. If the | |
288 | symbol is in the .bss segment, we need to include the size of | |
289 | the data segment in the offset as well. Fortunately, we know | |
290 | that at this point the size of the data section is in the NLM | |
291 | header. */ | |
292 | if (((bfd_get_section_flags (abfd, bfd_get_section (sym)) | |
cdbfad1c | 293 | & SEC_LOAD) == 0) |
7389debf ILT |
294 | && ((bfd_get_section_flags (abfd, bfd_get_section (sym)) |
295 | & SEC_ALLOC) != 0)) | |
296 | addend += nlm_fixed_header (abfd)->dataImageSize; | |
297 | ||
298 | if (addend != 0 | |
299 | && rel->howto != NULL | |
300 | && rel->howto->rightshift == 0 | |
301 | && rel->howto->size == 2 | |
302 | && rel->howto->bitsize == 32 | |
303 | && rel->howto->bitpos == 0 | |
7389debf ILT |
304 | && rel->howto->src_mask == 0xffffffff |
305 | && rel->howto->dst_mask == 0xffffffff) | |
306 | { | |
307 | bfd_vma val; | |
308 | ||
cdbfad1c | 309 | val = bfd_get_32 (abfd, (bfd_byte *) data + rel->address - offset); |
7389debf | 310 | val += addend; |
cdbfad1c | 311 | bfd_put_32 (abfd, val, (bfd_byte *) data + rel->address - offset); |
7389debf ILT |
312 | rel->addend = 0; |
313 | } | |
314 | ||
315 | /* NetWare uses a reloc with pcrel_offset set. We adjust | |
316 | pc_relative relocs accordingly. We are going to change the | |
317 | howto field, so we can only do this if the current one is | |
318 | compatible. We should check special_function here, but at | |
319 | the moment coff-i386 uses a special_function which does not | |
320 | affect what we are doing here. */ | |
321 | if (rel->howto != NULL | |
322 | && rel->howto->pc_relative | |
323 | && ! rel->howto->pcrel_offset | |
324 | && rel->howto->rightshift == 0 | |
325 | && rel->howto->size == 2 | |
326 | && rel->howto->bitsize == 32 | |
327 | && rel->howto->bitpos == 0 | |
7389debf ILT |
328 | && rel->howto->src_mask == 0xffffffff |
329 | && rel->howto->dst_mask == 0xffffffff) | |
330 | { | |
331 | bfd_vma val; | |
332 | ||
333 | /* When pcrel_offset is not set, it means that the negative | |
334 | of the address of the memory location is stored in the | |
335 | memory location. We must add it back in. */ | |
cdbfad1c | 336 | val = bfd_get_32 (abfd, (bfd_byte *) data + rel->address - offset); |
7389debf | 337 | val += rel->address; |
cdbfad1c | 338 | bfd_put_32 (abfd, val, (bfd_byte *) data + rel->address - offset); |
7389debf ILT |
339 | |
340 | rel->howto = &nlm_i386_pcrel_howto; | |
341 | } | |
342 | } | |
343 | ||
344 | return true; | |
345 | } | |
346 | ||
cdbfad1c ILT |
347 | /* Read a NetWare i386 import record */ |
348 | static boolean | |
349 | nlm_i386_read_import (abfd, sym) | |
350 | bfd *abfd; | |
351 | nlmNAME(symbol_type) *sym; | |
352 | { | |
353 | struct nlm_relent *nlm_relocs; /* relocation records for symbol */ | |
354 | bfd_size_type rcount; /* number of relocs */ | |
355 | bfd_byte temp[NLM_TARGET_LONG_SIZE]; /* temporary 32-bit value */ | |
356 | unsigned char symlength; /* length of symbol name */ | |
357 | ||
358 | if (bfd_read ((PTR) &symlength, sizeof (symlength), 1, abfd) | |
359 | != sizeof (symlength)) | |
360 | { | |
361 | bfd_error = system_call_error; | |
362 | return (false); | |
363 | } | |
364 | sym -> symbol.the_bfd = abfd; | |
365 | sym -> symbol.name = bfd_alloc (abfd, symlength + 1); | |
366 | if (bfd_read ((PTR) sym -> symbol.name, symlength, 1, abfd) | |
367 | != symlength) | |
368 | { | |
369 | bfd_error = system_call_error; | |
370 | return (false); | |
371 | } | |
372 | sym -> symbol.flags = 0; | |
373 | sym -> symbol.value = 0; | |
374 | sym -> symbol.section = &bfd_und_section; | |
375 | if (bfd_read ((PTR) temp, sizeof (temp), 1, abfd) != sizeof (temp)) | |
376 | { | |
377 | bfd_error = system_call_error; | |
378 | return (false); | |
379 | } | |
380 | rcount = bfd_h_get_32 (abfd, temp); | |
381 | nlm_relocs = ((struct nlm_relent *) | |
382 | bfd_alloc (abfd, rcount * sizeof (struct nlm_relent))); | |
383 | sym -> relocs = nlm_relocs; | |
384 | sym -> rcnt = 0; | |
385 | while (sym -> rcnt < rcount) | |
386 | { | |
387 | asection *section; | |
388 | ||
389 | if (nlm_i386_read_reloc (abfd, sym, §ion, | |
390 | &nlm_relocs -> reloc) | |
391 | == false) | |
392 | return false; | |
393 | nlm_relocs -> section = section; | |
394 | nlm_relocs++; | |
395 | sym -> rcnt++; | |
396 | } | |
397 | return true; | |
398 | } | |
399 | ||
400 | /* Write out an external reference. */ | |
401 | ||
402 | static boolean | |
403 | nlm_i386_write_external (abfd, count, sym, relocs) | |
404 | bfd *abfd; | |
405 | bfd_size_type count; | |
406 | asymbol *sym; | |
407 | struct reloc_and_sec *relocs; | |
408 | { | |
409 | int i; | |
410 | bfd_byte len; | |
411 | unsigned char temp[NLM_TARGET_LONG_SIZE]; | |
412 | ||
413 | len = strlen (sym->name); | |
414 | if ((bfd_write (&len, sizeof (bfd_byte), 1, abfd) != sizeof(bfd_byte)) | |
415 | || bfd_write (sym->name, len, 1, abfd) != len) | |
416 | { | |
417 | bfd_error = system_call_error; | |
418 | return false; | |
419 | } | |
420 | ||
421 | bfd_put_32 (abfd, count, temp); | |
422 | if (bfd_write (temp, sizeof(temp), 1, abfd) != sizeof (temp)) | |
423 | { | |
424 | bfd_error = system_call_error; | |
425 | return false; | |
426 | } | |
427 | ||
428 | for (i = 0; i < count; i++) | |
429 | { | |
430 | if (nlm_i386_write_import (abfd, relocs[i].sec, | |
431 | relocs[i].rel) == false) | |
432 | return false; | |
433 | } | |
434 | ||
435 | return true; | |
436 | } | |
437 | ||
438 | #include "nlmswap.h" | |
439 | ||
7389debf ILT |
440 | static const struct nlm_backend_data nlm32_i386_backend = |
441 | { | |
cdbfad1c ILT |
442 | "NetWare Loadable Module\032", |
443 | sizeof (Nlm32_i386_External_Fixed_Header), | |
444 | 0, /* optional_prefix_size */ | |
7389debf | 445 | bfd_arch_i386, |
cdbfad1c ILT |
446 | 0, |
447 | 0, /* backend_object_p */ | |
448 | 0, /* write_prefix_func */ | |
7389debf | 449 | nlm_i386_read_reloc, |
cdbfad1c ILT |
450 | nlm_i386_mangle_relocs, |
451 | nlm_i386_read_import, | |
452 | nlm_i386_write_import, | |
453 | 0, /* set_public_section */ | |
454 | 0, /* get_public_offset */ | |
455 | nlm_swap_fixed_header_in, | |
456 | nlm_swap_fixed_header_out, | |
457 | nlm_i386_write_external, | |
7389debf ILT |
458 | }; |
459 | ||
460 | #define TARGET_LITTLE_NAME "nlm32-i386" | |
461 | #define TARGET_LITTLE_SYM nlmNAME(i386_vec) | |
462 | #define TARGET_BACKEND_DATA &nlm32_i386_backend | |
463 | ||
464 | #include "nlm-target.h" |