bfd/elfxx-aarch64.h

   1 /* AArch64-specific backend routines.
   2    Copyright (C) 2009-2025 Free Software Foundation, Inc.
   3    Contributed by ARM Ltd.
   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; see the file COPYING3. If not,
  19    see <http://www.gnu.org/licenses/>.  */
  20
  21 extern void bfd_elf64_aarch64_init_maps
  22   (bfd *);
  23
  24 extern void bfd_elf32_aarch64_init_maps
  25   (bfd *);
  26
  27 /* Types of PLTs based on the level of security.  This would be a
  28    bit-mask to denote which of the combinations of security features
  29    are enabled:
  30    - No security feature PLTs
  31    - PLTs with BTI instruction
  32    - PLTs with PAC instruction
  33 */
  34 typedef enum
  35 {
  36   PLT_NORMAL    = 0x0,  /* Normal plts.  */
  37   PLT_BTI       = 0x1,  /* plts with BTI.  */
  38   PLT_PAC       = 0x2,  /* plts with pointer authentication.  */
  39   PLT_BTI_PAC   = PLT_BTI | PLT_PAC
  40 } aarch64_plt_type;
  41
  42 /* Indicates whether the linker should generate warnings, errors, or nothing
  43    when input objects are missing GNU feature property markings and the output
  44    has the markings.  */
  45 typedef enum
  46 {
  47   MARKING_NONE  = 0,  /* Does not emit any warning/error messages.  */
  48   MARKING_WARN  = 1,  /* Emit warning when the input objects are missing GNU
  49                          feature property markings, and the output has the
  50                          markings.  */
  51   MARKING_ERROR = 2,  /* Emit error when the input objects are missing GNU
  52                          feature property markings, and the output has the
  53                          markings.  */
  54   MARKING_UNSET = 3,  /* The only purpose of this value is to simulate an
  55                          optional to detect when the value was not initialized
  56                          from the command line.  */
  57 } aarch64_feature_marking_report;
  58
  59 /* To indicate whether GNU_PROPERTY_AARCH64_FEATURE_1_GCS bit is
  60    enabled/disabled on the output when -z gcs linker
  61    command line option is passed.  */
  62 typedef enum
  63 {
  64   GCS_NEVER     = 0,  /* gcs is disabled on output.  */
  65   GCS_IMPLICIT  = 1,  /* gcs is deduced from input object.  */
  66   GCS_ALWAYS    = 2,  /* gsc is enabled on output.  */
  67 } aarch64_gcs_type;
  68
  69 /* A structure to encompass all information about software protections coming
  70    from BTI, PAC and GCS related command line options.  */
  71 struct aarch64_protection_opts
  72 {
  73   /* PLT type to use depending on the selected software proctections.  */
  74   aarch64_plt_type plt_type;
  75
  76   /* Report level for BTI issues.  */
  77   aarch64_feature_marking_report bti_report;
  78
  79   /* Look-up mode for GCS property.  */
  80   aarch64_gcs_type gcs_type;
  81
  82   /* Report level for GCS issues.  */
  83   aarch64_feature_marking_report gcs_report;
  84
  85   /* Report level for GCS issues with dynamic inputs.  */
  86   aarch64_feature_marking_report gcs_report_dynamic;
  87 };
  88 typedef struct aarch64_protection_opts aarch64_protection_opts;
  89
  90 struct elf_aarch64_local_symbol;
  91 struct elf_aarch64_obj_tdata
  92 {
  93   struct elf_obj_tdata root;
  94
  95   /* local symbol descriptors */
  96   struct elf_aarch64_local_symbol *locals;
  97
  98   /* Zero to warn when linking objects with incompatible enum sizes.  */
  99   int no_enum_size_warning;
 100
 101   /* Zero to warn when linking objects with incompatible wchar_t sizes.  */
 102   int no_wchar_size_warning;
 103
 104   /* All GNU_PROPERTY_AARCH64_FEATURE_1_AND properties.  */
 105   uint32_t gnu_property_aarch64_feature_1_and;
 106
 107   /* Software protections options.  */
 108   struct aarch64_protection_opts sw_protections;
 109
 110   /* Number of reported BTI issues.  */
 111   int n_bti_issues;
 112
 113   /* Number of reported GCS issues for non-dynamic objects.  */
 114   int n_gcs_issues;
 115
 116   /* Number of reported GCS issues for dynamic objects.  */
 117   int n_gcs_dynamic_issues;
 118 };
 119
 120 #define elf_aarch64_tdata(bfd)                          \
 121   ((struct elf_aarch64_obj_tdata *) (bfd)->tdata.any)
 122
 123 /* An enum to define what kind of erratum fixes we should apply.  This gives the
 124    user a bit more control over the sequences we generate.  */
 125 typedef enum
 126 {
 127   ERRAT_NONE  = (1 << 0),  /* No erratum workarounds allowed.  */
 128   ERRAT_ADR   = (1 << 1),  /* Erratum workarounds using ADR allowed.  */
 129   ERRAT_ADRP  = (1 << 2),  /* Erratum workarounds using ADRP are allowed.  */
 130 } erratum_84319_opts;
 131
 132 extern void bfd_elf64_aarch64_set_options
 133   (bfd *, struct bfd_link_info *, int, int, int, int, erratum_84319_opts, int,
 134    const aarch64_protection_opts *);
 135
 136 extern void bfd_elf32_aarch64_set_options
 137   (bfd *, struct bfd_link_info *, int, int, int, int, erratum_84319_opts, int,
 138    const aarch64_protection_opts *);
 139
 140 /* AArch64 stub generation support for ELF64.  Called from the linker.  */
 141 extern int elf64_aarch64_setup_section_lists
 142   (bfd *, struct bfd_link_info *);
 143 extern void elf64_aarch64_next_input_section
 144   (struct bfd_link_info *, struct bfd_section *);
 145 extern bool elf64_aarch64_size_stubs
 146   (bfd *, bfd *, struct bfd_link_info *, bfd_signed_vma,
 147    struct bfd_section * (*) (const char *, struct bfd_section *),
 148    void (*) (void));
 149 extern bool elf64_aarch64_build_stubs
 150   (struct bfd_link_info *);
 151 /* AArch64 stub generation support for ELF32.  Called from the linker.  */
 152 extern int elf32_aarch64_setup_section_lists
 153   (bfd *, struct bfd_link_info *);
 154 extern void elf32_aarch64_next_input_section
 155   (struct bfd_link_info *, struct bfd_section *);
 156 extern bool elf32_aarch64_size_stubs
 157   (bfd *, bfd *, struct bfd_link_info *, bfd_signed_vma,
 158    struct bfd_section * (*) (const char *, struct bfd_section *),
 159    void (*) (void));
 160 extern bool elf32_aarch64_build_stubs
 161   (struct bfd_link_info *);
 162
 163 /* AArch64 relative relocation packing support for ELF64.  */
 164 extern bool elf64_aarch64_size_relative_relocs
 165   (struct bfd_link_info *, bool *);
 166 extern bool elf64_aarch64_finish_relative_relocs
 167   (struct bfd_link_info *);
 168 /* AArch64 relative relocation packing support for ELF32.  */
 169 extern bool elf32_aarch64_size_relative_relocs
 170   (struct bfd_link_info *, bool *);
 171 extern bool elf32_aarch64_finish_relative_relocs
 172   (struct bfd_link_info *);
 173
 174 /* Take the PAGE component of an address or offset.  */
 175 #define PG(x)        ((x) & ~ (bfd_vma) 0xfff)
 176 #define PG_OFFSET(x) ((x) &   (bfd_vma) 0xfff)
 177
 178 #define AARCH64_ADR_OP          0x10000000
 179 #define AARCH64_ADRP_OP         0x90000000
 180 #define AARCH64_ADRP_OP_MASK    0x9F000000
 181
 182 extern bfd_signed_vma
 183 _bfd_aarch64_sign_extend (bfd_vma, int);
 184
 185 extern uint32_t
 186 _bfd_aarch64_decode_adrp_imm (uint32_t);
 187
 188 extern uint32_t
 189 _bfd_aarch64_reencode_adr_imm (uint32_t, uint32_t);
 190
 191 extern bfd_reloc_status_type
 192 _bfd_aarch64_elf_put_addend (bfd *, bfd_byte *, bfd_reloc_code_real_type,
 193                              reloc_howto_type *, bfd_signed_vma);
 194
 195 extern bfd_vma
 196 _bfd_aarch64_elf_resolve_relocation (bfd *, bfd_reloc_code_real_type, bfd_vma,
 197                                      bfd_vma, bfd_vma, bool);
 198
 199 extern bool
 200 _bfd_aarch64_elf_grok_prstatus (bfd *, Elf_Internal_Note *);
 201
 202 extern bool
 203 _bfd_aarch64_elf_grok_psinfo (bfd *, Elf_Internal_Note *);
 204
 205 extern char *
 206 _bfd_aarch64_elf_write_core_note (bfd *, char *, int *, int, ...);
 207
 208 #define elf_backend_grok_prstatus       _bfd_aarch64_elf_grok_prstatus
 209 #define elf_backend_grok_psinfo         _bfd_aarch64_elf_grok_psinfo
 210 #define elf_backend_write_core_note     _bfd_aarch64_elf_write_core_note
 211
 212 extern bfd *
 213 _bfd_aarch64_elf_link_setup_gnu_properties (struct bfd_link_info *);
 214
 215 extern enum elf_property_kind
 216 _bfd_aarch64_elf_parse_gnu_properties (bfd *, unsigned int,
 217                                        bfd_byte *, unsigned int);
 218
 219 extern bool
 220 _bfd_aarch64_elf_merge_gnu_properties (struct bfd_link_info *, bfd *,
 221                                        elf_property *, elf_property *,
 222                                        uint32_t);
 223
 224 extern void
 225 _bfd_aarch64_elf_check_bti_report (struct bfd_link_info *, bfd *);
 226
 227 extern void
 228 _bfd_aarch64_elf_check_gcs_report (struct bfd_link_info *, bfd *);
 229
 230 extern void
 231 _bfd_aarch64_elf_link_fixup_gnu_properties (struct bfd_link_info *,
 232                                             elf_property_list **);
 233
 234 #define elf_backend_parse_gnu_properties        \
 235   _bfd_aarch64_elf_parse_gnu_properties
 236
 237 #define elf_backend_fixup_gnu_properties        \
 238   _bfd_aarch64_elf_link_fixup_gnu_properties