1 /* BFD backend for core files which use the ptrace_user structure
2    Copyright (C) 1993-2016 Free Software Foundation, Inc.
3    The structure of this file is based on trad-core.c written by John Gilmore
4    of Cygnus Support.
5    Modified to work with the ptrace_user structure by Kevin A. Buettner.
6    (Longterm it may be better to merge this file with trad-core.c)
7 
8    This file is part of BFD, the Binary File Descriptor library.
9 
10    This program is free software; you can redistribute it and/or modify
11    it under the terms of the GNU General Public License as published by
12    the Free Software Foundation; either version 3 of the License, or
13    (at your option) any later version.
14 
15    This program is distributed in the hope that it will be useful,
16    but WITHOUT ANY WARRANTY; without even the implied warranty of
17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18    GNU General Public License for more details.
19 
20    You should have received a copy of the GNU General Public License
21    along with this program; if not, write to the Free Software
22    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
23    MA 02110-1301, USA.  */
24 
25 #ifdef PTRACE_CORE
26 
27 #include "sysdep.h"
28 #include "bfd.h"
29 #include "libbfd.h"
30 
31 #include <sys/param.h>
32 #include <sys/dir.h>
33 #include <signal.h>
34 #include <sys/ptrace.h>
35 
36 struct trad_core_struct
37 {
38   asection *data_section;
39   asection *stack_section;
40   asection *reg_section;
41   struct ptrace_user u;
42 };
43 
44 #define core_upage(bfd)  (&((bfd)->tdata.trad_core_data->u))
45 #define core_datasec(bfd)  ((bfd)->tdata.trad_core_data->data_section)
46 #define core_stacksec(bfd) ((bfd)->tdata.trad_core_data->stack_section)
47 #define core_regsec(bfd)   ((bfd)->tdata.trad_core_data->reg_section)
48 
49 /* forward declarations */
50 
51 const bfd_target *ptrace_unix_core_file_p (bfd *abfd);
52 char * ptrace_unix_core_file_failing_command (bfd *abfd);
53 int ptrace_unix_core_file_failing_signal (bfd *abfd);
54 #define ptrace_unix_core_file_matches_executable_p generic_core_file_matches_executable_p
55 #define ptrace_unix_core_file_pid _bfd_nocore_core_file_pid
56 static void swap_abort (void);
57 
58 const bfd_target *
ptrace_unix_core_file_p(bfd * abfd)59 ptrace_unix_core_file_p (bfd *abfd)
60 {
61   int val;
62   struct ptrace_user u;
63   struct trad_core_struct *rawptr;
64   bfd_size_type amt;
65   flagword flags;
66 
67   val = bfd_bread ((void *)&u, (bfd_size_type) sizeof u, abfd);
68   if (val != sizeof u || u.pt_magic != _BCS_PTRACE_MAGIC
69       || u.pt_rev != _BCS_PTRACE_REV)
70     {
71       /* Too small to be a core file */
72       bfd_set_error (bfd_error_wrong_format);
73       return 0;
74     }
75 
76   /* OK, we believe you.  You're a core file (sure, sure).  */
77 
78   /* Allocate both the upage and the struct core_data at once, so
79      a single free() will free them both.  */
80   amt = sizeof (struct trad_core_struct);
81   rawptr = (struct trad_core_struct *) bfd_zalloc (abfd, amt);
82 
83   if (rawptr == NULL)
84     return 0;
85 
86   abfd->tdata.trad_core_data = rawptr;
87 
88   rawptr->u = u; /*Copy the uarea into the tdata part of the bfd */
89 
90   /* Create the sections.  */
91 
92   flags = SEC_ALLOC + SEC_LOAD + SEC_HAS_CONTENTS;
93   core_stacksec (abfd) = bfd_make_section_anyway_with_flags (abfd, ".stack",
94 							     flags);
95   if (core_stacksec (abfd) == NULL)
96     goto fail;
97   core_datasec (abfd) = bfd_make_section_anyway_with_flags (abfd, ".data",
98 							    flags);
99   if (core_datasec (abfd) == NULL)
100     goto fail;
101   core_regsec (abfd) = bfd_make_section_anyway_with_flags (abfd, ".reg",
102 							   SEC_HAS_CONTENTS);
103   if (core_regsec (abfd) == NULL)
104     goto fail;
105 
106   /* FIXME:  Need to worry about shared memory, library data, and library
107      text.  I don't think that any of these things are supported on the
108      system on which I am developing this for though.  */
109 
110   core_datasec (abfd)->size =  u.pt_dsize;
111   core_stacksec (abfd)->size = u.pt_ssize;
112   core_regsec (abfd)->size = sizeof (u);
113 
114   core_datasec (abfd)->vma = u.pt_o_data_start;
115   core_stacksec (abfd)->vma = USRSTACK - u.pt_ssize;
116   core_regsec (abfd)->vma = 0 - sizeof (u);	/* see trad-core.c */
117 
118   core_datasec (abfd)->filepos = (int) u.pt_dataptr;
119   core_stacksec (abfd)->filepos = (int) (u.pt_dataptr + u.pt_dsize);
120   core_regsec (abfd)->filepos = 0; /* Register segment is ptrace_user */
121 
122   /* Align to word at least */
123   core_stacksec (abfd)->alignment_power = 2;
124   core_datasec (abfd)->alignment_power = 2;
125   core_regsec (abfd)->alignment_power = 2;
126 
127   return abfd->xvec;
128 
129  fail:
130   bfd_release (abfd, abfd->tdata.any);
131   abfd->tdata.any = NULL;
132   bfd_section_list_clear (abfd);
133   return NULL;
134 }
135 
136 char *
ptrace_unix_core_file_failing_command(bfd * abfd)137 ptrace_unix_core_file_failing_command (bfd *abfd)
138 {
139   char *com = abfd->tdata.trad_core_data->u.pt_comm;
140 
141   if (*com)
142     return com;
143   else
144     return 0;
145 }
146 
147 int
ptrace_unix_core_file_failing_signal(bfd * abfd)148 ptrace_unix_core_file_failing_signal (bfd *abfd)
149 {
150   return abfd->tdata.trad_core_data->u.pt_sigframe.sig_num;
151 }
152 
153 /* If somebody calls any byte-swapping routines, shoot them.  */
154 static void
swap_abort(void)155 swap_abort (void)
156 {
157   abort (); /* This way doesn't require any declaration for ANSI to fuck up */
158 }
159 
160 #define	NO_GET ((bfd_vma (*) (const void *)) swap_abort)
161 #define	NO_PUT ((void (*) (bfd_vma, void *)) swap_abort)
162 #define	NO_GETS ((bfd_signed_vma (*) (const void *)) swap_abort)
163 #define	NO_GET64 ((bfd_uint64_t (*) (const void *)) swap_abort)
164 #define	NO_PUT64 ((void (*) (bfd_uint64_t, void *)) swap_abort)
165 #define	NO_GETS64 ((bfd_int64_t (*) (const void *)) swap_abort)
166 
167 const bfd_target core_ptrace_vec =
168   {
169     "trad-core",
170     bfd_target_unknown_flavour,
171     BFD_ENDIAN_UNKNOWN,		/* target byte order */
172     BFD_ENDIAN_UNKNOWN,		/* target headers byte order */
173     (HAS_RELOC | EXEC_P |	/* object flags */
174      HAS_LINENO | HAS_DEBUG |
175      HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
176     (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */
177     0,			                                   /* symbol prefix */
178     ' ',						   /* ar_pad_char */
179     16,							   /* ar_max_namelen */
180     NO_GET64, NO_GETS64, NO_PUT64,	/* 64 bit data */
181     NO_GET, NO_GETS, NO_PUT,		/* 32 bit data */
182     NO_GET, NO_GETS, NO_PUT,		/* 16 bit data */
183     NO_GET64, NO_GETS64, NO_PUT64,	/* 64 bit hdrs */
184     NO_GET, NO_GETS, NO_PUT,		/* 32 bit hdrs */
185     NO_GET, NO_GETS, NO_PUT,		/* 16 bit hdrs */
186 
187     {				/* bfd_check_format */
188       _bfd_dummy_target,		/* unknown format */
189       _bfd_dummy_target,		/* object file */
190       _bfd_dummy_target,		/* archive */
191       ptrace_unix_core_file_p		/* a core file */
192     },
193     {				/* bfd_set_format */
194       bfd_false, bfd_false,
195       bfd_false, bfd_false
196     },
197     {				/* bfd_write_contents */
198       bfd_false, bfd_false,
199       bfd_false, bfd_false
200     },
201 
202     BFD_JUMP_TABLE_GENERIC (_bfd_generic),
203     BFD_JUMP_TABLE_COPY (_bfd_generic),
204     BFD_JUMP_TABLE_CORE (ptrace_unix),
205     BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive),
206     BFD_JUMP_TABLE_SYMBOLS (_bfd_nosymbols),
207     BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
208     BFD_JUMP_TABLE_WRITE (_bfd_generic),
209     BFD_JUMP_TABLE_LINK (_bfd_nolink),
210     BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
211 
212     NULL,
213 
214     NULL			/* backend_data */
215   };
216 
217 #endif /* PTRACE_CORE */
218