1 /* BFD back-end for PPCbug boot records.
2    Copyright (C) 1996-2014 Free Software Foundation, Inc.
3    Written by Michael Meissner, Cygnus Support, <meissner@cygnus.com>
4 
5    This file is part of BFD, the Binary File Descriptor library.
6 
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 3 of the License, or
10    (at your option) any later version.
11 
12    This program is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16 
17    You should have received a copy of the GNU General Public License
18    along with this program; if not, write to the Free Software
19    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
20    MA 02110-1301, USA.  */
21 
22 
23 /* This is a BFD backend which may be used to write PowerPCBug boot objects.
24    It may only be used for output, not input.  The intention is that this may
25    be used as an output format for objcopy in order to generate raw binary
26    data.
27 
28    This is very simple.  The only complication is that the real data
29    will start at some address X, and in some cases we will not want to
30    include X zeroes just to get to that point.  Since the start
31    address is not meaningful for this object file format, we use it
32    instead to indicate the number of zeroes to skip at the start of
33    the file.  objcopy cooperates by specially setting the start
34    address to zero by default.  */
35 
36 #include "sysdep.h"
37 #include "safe-ctype.h"
38 #include "bfd.h"
39 #include "libbfd.h"
40 
41 /* PPCbug location structure */
42 typedef struct ppcboot_location
43 {
44   bfd_byte	ind;
45   bfd_byte	head;
46   bfd_byte	sector;
47   bfd_byte	cylinder;
48 } ppcboot_location_t;
49 
50 /* PPCbug partition table layout */
51 typedef struct ppcboot_partition
52 {
53   ppcboot_location_t	partition_begin;	/* partition begin */
54   ppcboot_location_t	partition_end;		/* partition end */
55   bfd_byte		sector_begin[4];	/* 32-bit start RBA (zero-based), little endian */
56   bfd_byte		sector_length[4];	/* 32-bit RBA count (one-based), little endian */
57 } ppcboot_partition_t;
58 
59 /* PPCbug boot layout.  */
60 typedef struct ppcboot_hdr
61 {
62   bfd_byte		pc_compatibility[446];	/* x86 instruction field */
63   ppcboot_partition_t	partition[4];		/* partition information */
64   bfd_byte		signature[2];		/* 0x55 and 0xaa */
65   bfd_byte		entry_offset[4];	/* entry point offset, little endian */
66   bfd_byte		length[4];		/* load image length, little endian */
67   bfd_byte		flags;			/* flag field */
68   bfd_byte		os_id;			/* OS_ID */
69   char			partition_name[32];	/* partition name */
70   bfd_byte		reserved1[470];		/* reserved */
71 }
72 #ifdef __GNUC__
73   __attribute__ ((packed))
74 #endif
75 ppcboot_hdr_t;
76 
77 /* Signature bytes for last 2 bytes of the 512 byte record */
78 #define SIGNATURE0 0x55
79 #define SIGNATURE1 0xaa
80 
81 /* PowerPC boot type */
82 #define PPC_IND 0x41
83 
84 /* Information needed for ppcboot header */
85 typedef struct ppcboot_data
86 {
87   ppcboot_hdr_t	header;				/* raw header */
88   asection *sec;				/* single section */
89 } ppcboot_data_t;
90 
91 /* Any bfd we create by reading a ppcboot file has three symbols:
92    a start symbol, an end symbol, and an absolute length symbol.  */
93 #define PPCBOOT_SYMS 3
94 
95 #define ppcboot_set_tdata(abfd, ptr) ((abfd)->tdata.any = (ptr))
96 #define ppcboot_get_tdata(abfd) ((ppcboot_data_t *) ((abfd)->tdata.any))
97 
98 /* Create a ppcboot object.  Invoked via bfd_set_format.  */
99 
100 static bfd_boolean
ppcboot_mkobject(bfd * abfd)101 ppcboot_mkobject (bfd *abfd)
102 {
103   if (!ppcboot_get_tdata (abfd))
104     {
105       bfd_size_type amt = sizeof (ppcboot_data_t);
106       ppcboot_set_tdata (abfd, bfd_zalloc (abfd, amt));
107     }
108 
109   return TRUE;
110 }
111 
112 
113 /* Set the architecture to PowerPC */
114 static bfd_boolean
ppcboot_set_arch_mach(bfd * abfd,enum bfd_architecture arch,unsigned long machine)115 ppcboot_set_arch_mach (bfd *abfd,
116 		       enum bfd_architecture arch,
117 		       unsigned long machine)
118 {
119   if (arch == bfd_arch_unknown)
120     arch = bfd_arch_powerpc;
121 
122   else if (arch != bfd_arch_powerpc)
123     return FALSE;
124 
125   return bfd_default_set_arch_mach (abfd, arch, machine);
126 }
127 
128 
129 /* Any file may be considered to be a ppcboot file, provided the target
130    was not defaulted.  That is, it must be explicitly specified as
131    being ppcboot.  */
132 
133 static const bfd_target *
ppcboot_object_p(bfd * abfd)134 ppcboot_object_p (bfd *abfd)
135 {
136   struct stat statbuf;
137   asection *sec;
138   ppcboot_hdr_t hdr;
139   size_t i;
140   ppcboot_data_t *tdata;
141   flagword flags;
142 
143   BFD_ASSERT (sizeof (ppcboot_hdr_t) == 1024);
144 
145   if (abfd->target_defaulted)
146     {
147       bfd_set_error (bfd_error_wrong_format);
148       return NULL;
149     }
150 
151   /* Find the file size.  */
152   if (bfd_stat (abfd, &statbuf) < 0)
153     {
154       bfd_set_error (bfd_error_system_call);
155       return NULL;
156     }
157 
158   if ((size_t) statbuf.st_size < sizeof (ppcboot_hdr_t))
159     {
160       bfd_set_error (bfd_error_wrong_format);
161       return NULL;
162     }
163 
164   if (bfd_bread (&hdr, (bfd_size_type) sizeof (hdr), abfd)
165       != sizeof (hdr))
166     {
167       if (bfd_get_error () != bfd_error_system_call)
168 	bfd_set_error (bfd_error_wrong_format);
169 
170       return NULL;
171     }
172 
173   /* Now do some basic checks.  */
174   for (i = 0; i < sizeof (hdr.pc_compatibility); i++)
175     if (hdr.pc_compatibility[i])
176       {
177 	bfd_set_error (bfd_error_wrong_format);
178 	return NULL;
179       }
180 
181   if (hdr.signature[0] != SIGNATURE0 || hdr.signature[1] != SIGNATURE1)
182     {
183       bfd_set_error (bfd_error_wrong_format);
184       return NULL;
185     }
186 
187   if (hdr.partition[0].partition_end.ind != PPC_IND)
188     {
189       bfd_set_error (bfd_error_wrong_format);
190       return NULL;
191     }
192 
193   abfd->symcount = PPCBOOT_SYMS;
194 
195   /* One data section.  */
196   flags = SEC_ALLOC | SEC_LOAD | SEC_DATA | SEC_CODE | SEC_HAS_CONTENTS;
197   sec = bfd_make_section_with_flags (abfd, ".data", flags);
198   if (sec == NULL)
199     return NULL;
200   sec->vma = 0;
201   sec->size = statbuf.st_size - sizeof (ppcboot_hdr_t);
202   sec->filepos = sizeof (ppcboot_hdr_t);
203 
204   ppcboot_mkobject (abfd);
205   tdata = ppcboot_get_tdata (abfd);
206   tdata->sec = sec;
207   memcpy (&tdata->header, &hdr, sizeof (ppcboot_hdr_t));
208 
209   ppcboot_set_arch_mach (abfd, bfd_arch_powerpc, 0L);
210   return abfd->xvec;
211 }
212 
213 #define ppcboot_close_and_cleanup _bfd_generic_close_and_cleanup
214 #define ppcboot_bfd_free_cached_info _bfd_generic_bfd_free_cached_info
215 #define ppcboot_new_section_hook _bfd_generic_new_section_hook
216 
217 
218 /* Get contents of the only section.  */
219 
220 static bfd_boolean
ppcboot_get_section_contents(bfd * abfd,asection * section ATTRIBUTE_UNUSED,void * location,file_ptr offset,bfd_size_type count)221 ppcboot_get_section_contents (bfd *abfd,
222 			      asection *section ATTRIBUTE_UNUSED,
223 			      void * location,
224 			      file_ptr offset,
225 			      bfd_size_type count)
226 {
227   if (bfd_seek (abfd, offset + (file_ptr) sizeof (ppcboot_hdr_t), SEEK_SET) != 0
228       || bfd_bread (location, count, abfd) != count)
229     return FALSE;
230   return TRUE;
231 }
232 
233 
234 /* Return the amount of memory needed to read the symbol table.  */
235 
236 static long
ppcboot_get_symtab_upper_bound(bfd * abfd ATTRIBUTE_UNUSED)237 ppcboot_get_symtab_upper_bound (bfd *abfd ATTRIBUTE_UNUSED)
238 {
239   return (PPCBOOT_SYMS + 1) * sizeof (asymbol *);
240 }
241 
242 
243 /* Create a symbol name based on the bfd's filename.  */
244 
245 static char *
mangle_name(bfd * abfd,char * suffix)246 mangle_name (bfd *abfd, char *suffix)
247 {
248   bfd_size_type size;
249   char *buf;
250   char *p;
251 
252   size = (strlen (bfd_get_filename (abfd))
253 	  + strlen (suffix)
254 	  + sizeof "_ppcboot__");
255 
256   buf = (char *) bfd_alloc (abfd, size);
257   if (buf == NULL)
258     return "";
259 
260   sprintf (buf, "_ppcboot_%s_%s", bfd_get_filename (abfd), suffix);
261 
262   /* Change any non-alphanumeric characters to underscores.  */
263   for (p = buf; *p; p++)
264     if (! ISALNUM (*p))
265       *p = '_';
266 
267   return buf;
268 }
269 
270 
271 /* Return the symbol table.  */
272 
273 static long
ppcboot_canonicalize_symtab(bfd * abfd,asymbol ** alocation)274 ppcboot_canonicalize_symtab (bfd *abfd, asymbol **alocation)
275 {
276   asection *sec = ppcboot_get_tdata (abfd)->sec;
277   asymbol *syms;
278   unsigned int i;
279   bfd_size_type amt = PPCBOOT_SYMS * sizeof (asymbol);
280 
281   syms = (asymbol *) bfd_alloc (abfd, amt);
282   if (syms == NULL)
283     return FALSE;
284 
285   /* Start symbol.  */
286   syms[0].the_bfd = abfd;
287   syms[0].name = mangle_name (abfd, "start");
288   syms[0].value = 0;
289   syms[0].flags = BSF_GLOBAL;
290   syms[0].section = sec;
291   syms[0].udata.p = NULL;
292 
293   /* End symbol.  */
294   syms[1].the_bfd = abfd;
295   syms[1].name = mangle_name (abfd, "end");
296   syms[1].value = sec->size;
297   syms[1].flags = BSF_GLOBAL;
298   syms[1].section = sec;
299   syms[1].udata.p = NULL;
300 
301   /* Size symbol.  */
302   syms[2].the_bfd = abfd;
303   syms[2].name = mangle_name (abfd, "size");
304   syms[2].value = sec->size;
305   syms[2].flags = BSF_GLOBAL;
306   syms[2].section = bfd_abs_section_ptr;
307   syms[2].udata.p = NULL;
308 
309   for (i = 0; i < PPCBOOT_SYMS; i++)
310     *alocation++ = syms++;
311   *alocation = NULL;
312 
313   return PPCBOOT_SYMS;
314 }
315 
316 #define ppcboot_make_empty_symbol _bfd_generic_make_empty_symbol
317 #define ppcboot_print_symbol _bfd_nosymbols_print_symbol
318 
319 /* Get information about a symbol.  */
320 
321 static void
ppcboot_get_symbol_info(bfd * ignore_abfd ATTRIBUTE_UNUSED,asymbol * symbol,symbol_info * ret)322 ppcboot_get_symbol_info (bfd *ignore_abfd ATTRIBUTE_UNUSED,
323 			 asymbol *symbol,
324 			 symbol_info *ret)
325 {
326   bfd_symbol_info (symbol, ret);
327 }
328 
329 #define ppcboot_bfd_is_target_special_symbol \
330   ((bfd_boolean (*) (bfd *, asymbol *)) bfd_false)
331 #define ppcboot_bfd_is_local_label_name bfd_generic_is_local_label_name
332 #define ppcboot_get_lineno _bfd_nosymbols_get_lineno
333 #define ppcboot_find_nearest_line _bfd_nosymbols_find_nearest_line
334 #define ppcboot_find_line _bfd_nosymbols_find_line
335 #define ppcboot_find_inliner_info _bfd_nosymbols_find_inliner_info
336 #define ppcboot_bfd_make_debug_symbol _bfd_nosymbols_bfd_make_debug_symbol
337 #define ppcboot_read_minisymbols _bfd_generic_read_minisymbols
338 #define ppcboot_minisymbol_to_symbol _bfd_generic_minisymbol_to_symbol
339 
340 /* Write section contents of a ppcboot file.  */
341 
342 static bfd_boolean
ppcboot_set_section_contents(bfd * abfd,asection * sec,const void * data,file_ptr offset,bfd_size_type size)343 ppcboot_set_section_contents (bfd *abfd,
344 			      asection *sec,
345 			      const void * data,
346 			      file_ptr offset,
347 			      bfd_size_type size)
348 {
349   if (! abfd->output_has_begun)
350     {
351       bfd_vma low;
352       asection *s;
353 
354       /* The lowest section VMA sets the virtual address of the start
355          of the file.  We use the set the file position of all the
356          sections.  */
357       low = abfd->sections->vma;
358       for (s = abfd->sections->next; s != NULL; s = s->next)
359 	if (s->vma < low)
360 	  low = s->vma;
361 
362       for (s = abfd->sections; s != NULL; s = s->next)
363 	s->filepos = s->vma - low;
364 
365       abfd->output_has_begun = TRUE;
366     }
367 
368   return _bfd_generic_set_section_contents (abfd, sec, data, offset, size);
369 }
370 
371 
372 static int
ppcboot_sizeof_headers(bfd * abfd ATTRIBUTE_UNUSED,struct bfd_link_info * info ATTRIBUTE_UNUSED)373 ppcboot_sizeof_headers (bfd *abfd ATTRIBUTE_UNUSED,
374 			struct bfd_link_info *info ATTRIBUTE_UNUSED)
375 {
376   return sizeof (ppcboot_hdr_t);
377 }
378 
379 
380 /* Print out the program headers.  */
381 
382 static bfd_boolean
ppcboot_bfd_print_private_bfd_data(bfd * abfd,void * farg)383 ppcboot_bfd_print_private_bfd_data (bfd *abfd, void * farg)
384 {
385   FILE *f = (FILE *)farg;
386   ppcboot_data_t *tdata = ppcboot_get_tdata (abfd);
387   long entry_offset = bfd_getl_signed_32 (tdata->header.entry_offset);
388   long length = bfd_getl_signed_32 (tdata->header.length);
389   int i;
390 
391   fprintf (f, _("\nppcboot header:\n"));
392   fprintf (f, _("Entry offset        = 0x%.8lx (%ld)\n"),
393 	   (unsigned long) entry_offset, entry_offset);
394   fprintf (f, _("Length              = 0x%.8lx (%ld)\n"),
395 	   (unsigned long) length, length);
396 
397   if (tdata->header.flags)
398     fprintf (f, _("Flag field          = 0x%.2x\n"), tdata->header.flags);
399 
400   if (tdata->header.os_id)
401     fprintf (f, "OS_ID               = 0x%.2x\n", tdata->header.os_id);
402 
403   if (tdata->header.partition_name)
404     fprintf (f, _("Partition name      = \"%s\"\n"), tdata->header.partition_name);
405 
406   for (i = 0; i < 4; i++)
407     {
408       long sector_begin  = bfd_getl_signed_32 (tdata->header.partition[i].sector_begin);
409       long sector_length = bfd_getl_signed_32 (tdata->header.partition[i].sector_length);
410 
411       /* Skip all 0 entries */
412       if (!tdata->header.partition[i].partition_begin.ind
413 	  && !tdata->header.partition[i].partition_begin.head
414 	  && !tdata->header.partition[i].partition_begin.sector
415 	  && !tdata->header.partition[i].partition_begin.cylinder
416 	  && !tdata->header.partition[i].partition_end.ind
417 	  && !tdata->header.partition[i].partition_end.head
418 	  && !tdata->header.partition[i].partition_end.sector
419 	  && !tdata->header.partition[i].partition_end.cylinder
420 	  && !sector_begin && !sector_length)
421 	continue;
422 
423       fprintf (f, _("\nPartition[%d] start  = { 0x%.2x, 0x%.2x, 0x%.2x, 0x%.2x }\n"), i,
424 	       tdata->header.partition[i].partition_begin.ind,
425 	       tdata->header.partition[i].partition_begin.head,
426 	       tdata->header.partition[i].partition_begin.sector,
427 	       tdata->header.partition[i].partition_begin.cylinder);
428 
429       fprintf (f, _("Partition[%d] end    = { 0x%.2x, 0x%.2x, 0x%.2x, 0x%.2x }\n"), i,
430 	       tdata->header.partition[i].partition_end.ind,
431 	       tdata->header.partition[i].partition_end.head,
432 	       tdata->header.partition[i].partition_end.sector,
433 	       tdata->header.partition[i].partition_end.cylinder);
434 
435       fprintf (f, _("Partition[%d] sector = 0x%.8lx (%ld)\n"),
436 	       i, (unsigned long) sector_begin, sector_begin);
437       fprintf (f, _("Partition[%d] length = 0x%.8lx (%ld)\n"),
438 	       i, (unsigned long) sector_length, sector_length);
439     }
440 
441   fprintf (f, "\n");
442   return TRUE;
443 }
444 
445 
446 #define ppcboot_bfd_get_relocated_section_contents \
447   bfd_generic_get_relocated_section_contents
448 #define ppcboot_bfd_relax_section bfd_generic_relax_section
449 #define ppcboot_bfd_gc_sections bfd_generic_gc_sections
450 #define ppcboot_bfd_lookup_section_flags bfd_generic_lookup_section_flags
451 #define ppcboot_bfd_merge_sections bfd_generic_merge_sections
452 #define ppcboot_bfd_is_group_section bfd_generic_is_group_section
453 #define ppcboot_bfd_discard_group bfd_generic_discard_group
454 #define ppcboot_section_already_linked \
455   _bfd_generic_section_already_linked
456 #define ppcboot_bfd_define_common_symbol bfd_generic_define_common_symbol
457 #define ppcboot_bfd_link_hash_table_create _bfd_generic_link_hash_table_create
458 #define ppcboot_bfd_link_add_symbols _bfd_generic_link_add_symbols
459 #define ppcboot_bfd_link_just_syms _bfd_generic_link_just_syms
460 #define ppcboot_bfd_copy_link_hash_symbol_type \
461   _bfd_generic_copy_link_hash_symbol_type
462 #define ppcboot_bfd_final_link _bfd_generic_final_link
463 #define ppcboot_bfd_link_split_section _bfd_generic_link_split_section
464 #define ppcboot_get_section_contents_in_window \
465   _bfd_generic_get_section_contents_in_window
466 
467 #define ppcboot_bfd_copy_private_bfd_data _bfd_generic_bfd_copy_private_bfd_data
468 #define ppcboot_bfd_merge_private_bfd_data _bfd_generic_bfd_merge_private_bfd_data
469 #define ppcboot_bfd_copy_private_section_data _bfd_generic_bfd_copy_private_section_data
470 #define ppcboot_bfd_copy_private_symbol_data _bfd_generic_bfd_copy_private_symbol_data
471 #define ppcboot_bfd_copy_private_header_data _bfd_generic_bfd_copy_private_header_data
472 #define ppcboot_bfd_set_private_flags _bfd_generic_bfd_set_private_flags
473 #define ppcboot_bfd_print_private_bfd_dat ppcboot_bfd_print_private_bfd_data
474 
475 const bfd_target powerpc_boot_vec =
476 {
477   "ppcboot",			/* name */
478   bfd_target_unknown_flavour,	/* flavour */
479   BFD_ENDIAN_BIG,		/* byteorder is big endian for code */
480   BFD_ENDIAN_LITTLE,		/* header_byteorder */
481   EXEC_P,			/* object_flags */
482   (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE | SEC_DATA
483    | SEC_ROM | SEC_HAS_CONTENTS), /* section_flags */
484   0,				/* symbol_leading_char */
485   ' ',				/* ar_pad_char */
486   16,				/* ar_max_namelen */
487   0,				/* match priority.  */
488   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
489   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
490   bfd_getb16, bfd_getb_signed_16, bfd_putb16,	/* data */
491   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
492   bfd_getl32, bfd_getl_signed_32, bfd_putl32,
493   bfd_getl16, bfd_getl_signed_16, bfd_putl16,	/* hdrs */
494   {				/* bfd_check_format */
495     _bfd_dummy_target,
496     ppcboot_object_p,		/* bfd_check_format */
497     _bfd_dummy_target,
498     _bfd_dummy_target,
499   },
500   {				/* bfd_set_format */
501     bfd_false,
502     ppcboot_mkobject,
503     bfd_false,
504     bfd_false,
505   },
506   {				/* bfd_write_contents */
507     bfd_false,
508     bfd_true,
509     bfd_false,
510     bfd_false,
511   },
512 
513   BFD_JUMP_TABLE_GENERIC (ppcboot),
514   BFD_JUMP_TABLE_COPY (ppcboot),
515   BFD_JUMP_TABLE_CORE (_bfd_nocore),
516   BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive),
517   BFD_JUMP_TABLE_SYMBOLS (ppcboot),
518   BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
519   BFD_JUMP_TABLE_WRITE (ppcboot),
520   BFD_JUMP_TABLE_LINK (ppcboot),
521   BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
522 
523   NULL,
524 
525   NULL
526 };
527