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macho: Support sections
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@dd86k
dd86k committed Jun 23, 2024
1 parent be4817c commit e13f4bd
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Showing 2 changed files with 221 additions and 17 deletions.
59 changes: 55 additions & 4 deletions dumper/format/macho.d
View file
Original file line number Diff line number Diff line change
Expand Up @@ -9,13 +9,16 @@ import adbg.disassembler;
import adbg.object.server;
import adbg.object.format.macho;
import dumper;
import common.error;

int dump_macho(adbg_object_t *o) {
if (SELECTED(Select.headers))
adbg_object_macho_is_fat(o) ?
dump_macho_header_fat(o) : dump_macho_header_regular(o);
if (SELECTED(Select.segments))
dump_macho_segments(o);
if (SELECTED(Select.sections))
dump_macho_sections(o);

return 0;
}
Expand Down Expand Up @@ -94,12 +97,12 @@ void dump_macho_segments(adbg_object_t *o) {

size_t i;
macho_load_command_t *command = void;
while ((command = adbg_object_macho_load_command(o, i++)) != null) with (command) {
for (; (command = adbg_object_macho_load_command(o, i)) != null; ++i) {
print_section(cast(uint)i);
print_x32("cmd", cmd, SAFEVAL(adbg_object_macho_command_string(cmd)));
print_x32("cmdsize", cmdsize);
print_x32("cmd", command.cmd, SAFEVAL(adbg_object_macho_command_string(command.cmd)));
print_x32("cmdsize", command.cmdsize);

switch (cmd) {
switch (command.cmd) {
case MACHO_LC_SEGMENT:
macho_segment_command_t *seg = cast(macho_segment_command_t*)command;
print_stringl("segname", seg.segname.ptr, cast(uint)seg.segname.sizeof);
Expand Down Expand Up @@ -127,4 +130,52 @@ void dump_macho_segments(adbg_object_t *o) {
default: continue;
}
}
if (i == 0)
panic_adbg();
}

void dump_macho_sections(adbg_object_t *o) {
print_header("Sections");

int i64 = adbg_object_macho_is_64bit(o);
size_t i;
macho_load_command_t *command = void;
for (; (command = adbg_object_macho_load_command(o, i)) != null; ++i) {
size_t si;
void *section = void;
for (; (section = adbg_object_macho_segment_section(o, command, si)) != null; ++si) {
print_section(cast(uint)i);
i64 ?
dump_macho_section32(cast(macho_section_t*)section) :
dump_macho_section64(cast(macho_section64_t*)section);
}
}
}
void dump_macho_section32(macho_section_t *section) {
print_stringl("sectname", section.sectname.ptr, section.sectname.sizeof);
print_stringl("sectname", section.segname.ptr, section.segname.sizeof);
print_x32("addr", section.addr);
print_x32("size", section.size);
print_x32("offset", section.offset);
print_x32("align", section.align_);
print_x32("reloff", section.reloff);
print_x32("nrelocs", section.nrelocs);
print_x32("flags", section.flags);
print_x32("reserved1", section.reserved1);
print_x32("reserved2", section.reserved2);
}
void dump_macho_section64(macho_section64_t *section) {
print_stringl("sectname", section.sectname.ptr, section.sectname.sizeof);
print_stringl("sectname", section.segname.ptr, section.segname.sizeof);
print_x64("addr", section.addr);
print_x64("size", section.size);
print_x32("offset", section.offset);
print_x32("align", section.align_);
print_x32("reloff", section.reloff);
print_x32("nrelocs", section.nrelocs);
print_x32("flags", section.flags);
print_x32("reserved1", section.reserved1);
print_x32("reserved2", section.reserved2);
print_x32("reserved3", section.reserved3);

}
179 changes: 166 additions & 13 deletions src/adbg/object/format/macho.d
View file
Original file line number Diff line number Diff line change
Expand Up @@ -399,6 +399,102 @@ struct macho_segment_command_64_t { /* for 64-bit architectures */
uint flags; /// flags
}

enum MACHO_SECTION_TYPE = 0x000000ff; /// Section flags type mask
enum MACHO_SECTION_ATTR = 0xffffff00; /// Section flags attributes mask

// Constants for the section attributes part of the flags field of a section
// structure.

/// User setable attributes
enum MACHO_SECTION_ATTRIBUTES_USR = 0xff000000;
/// section contains only true machine instructions
enum MACHO_S_ATTR_PURE_INSTRUCTIONS = 0x80000000;
/// section contains coalesced symbols that are not to be in a ranlib table of contents
enum MACHO_S_ATTR_NO_TOC = 0x40000000;
/// ok to strip static symbols in this section in files with the MH_DYLDLINK flag
enum MACHO_S_ATTR_STRIP_STATIC_SYMS = 0x20000000;
/// no dead stripping
enum MACHO_S_ATTR_NO_DEAD_STRIP = 0x10000000;
/// blocks are live if they reference live blocks
enum MACHO_S_ATTR_LIVE_SUPPORT = 0x08000000;
/// Used with i386 code stubs written on by dyld
enum MACHO_S_ATTR_SELF_MODIFYING_CODE = 0x04000000;

// Constants for the type of a section

/// regular section
enum MACHO_S_REGULAR = 0x0;
/// zero fill on demand section
enum MACHO_S_ZEROFILL = 0x1;
/// section with only literal C strings
enum MACHO_S_CSTRING_LITERALS = 0x2;
/// section with only 4 byte literals
enum MACHO_S_4BYTE_LITERALS = 0x3;
/// section with only 8 byte literals
enum MACHO_S_8BYTE_LITERALS = 0x4;
/// section with only pointers to literals
enum MACHO_S_LITERAL_POINTERS = 0x5;
/// section with only non-lazy symbol pointers
enum MACHO_S_NON_LAZY_SYMBOL_POINTERS = 0x6;
/// section with only lazy symbol pointers
enum MACHO_S_LAZY_SYMBOL_POINTERS = 0x7;
/// section with only symbol stubs, byte size of stub in the reserved2 field
enum MACHO_S_SYMBOL_STUBS = 0x8;
/// section with only function pointers for initialization
enum MACHO_S_MOD_INIT_FUNC_POINTERS = 0x9;
/// section with only function pointers for termination
enum MACHO_S_MOD_TERM_FUNC_POINTERS = 0xa;
/// section contains symbols that are to be coalesced
enum MACHO_S_COALESCED = 0xb;
/// zero fill on demand section (that can be larger than 4 gigabytes
enum MACHO_S_GB_ZEROFILL = 0xc;
/// section with only pairs of function pointers for interposing
enum MACHO_S_INTERPOSING = 0xd;
/// section with only 16 byte literals
enum MACHO_S_16BYTE_LITERALS = 0xe;
/// section contains DTrace Object Format
enum MACHO_S_DTRACE_DOF = 0xf;
/// section with only lazy symbol pointers to lazy loaded dylibs
enum MACHO_S_LAZY_DYLIB_SYMBOL_POINTERS = 0x10;
/// TLS: template of initial values for TLVs
enum MACHO_S_THREAD_LOCAL_REGULAR = 0x11;
/// TLS: template of initial values for TLVs
enum MACHO_S_THREAD_LOCAL_ZEROFILL = 0x12;
/// TLS: TLV descriptors
enum MACHO_S_THREAD_LOCAL_VARIABLES = 0x13;
/// TLS: pointers to TLV descriptors
enum MACHO_S_THREAD_LOCAL_VARIABLE_POINTERS = 0x14;
/// TLS: functions to call to initialize TLV values
enum MACHO_S_THREAD_LOCAL_INIT_FUNCTION_POINTERS = 0x15;

struct macho_section_t {
char[16] sectname; /// Section name
char[16] segname; /// Name of parent segment
uint addr; /// Memory address
uint size; /// Size of section
uint offset; /// File offset to this section
uint align_; /// Section alignment, power of 2
uint reloff; /// File offset to relocation entries
uint nrelocs; /// Number of relocation entries
uint flags; /// Flags
uint reserved1; ///
uint reserved2; ///
}
struct macho_section64_t {
char[16] sectname; /// Section name
char[16] segname; /// Name of parent segment
ulong addr; /// Memory address
ulong size; /// Size of section
uint offset; /// File offset to this section
uint align_; /// Section alignment, power of 2
uint reloff; /// File offset to relocation entries
uint nrelocs; /// Number of relocation entries
uint flags; /// Flags
uint reserved1; ///
uint reserved2; ///
uint reserved3; ///
}

private
struct internal_macho_t {
union {
Expand All @@ -413,10 +509,11 @@ struct internal_macho_t {
bool *r_commands;
bool *r_fat_entries;
}
bool *r_sections;
}
private enum {
MACHO_S_64 = 1 << 16,
MACHO_S_FAT = 1 << 17,
MACHO_IS_64 = 1 << 16,
MACHO_IS_FAT = 1 << 17,
}

int adbg_object_macho_load(adbg_object_t *o, uint magic) {
Expand All @@ -434,23 +531,23 @@ int adbg_object_macho_load(adbg_object_t *o, uint magic) {
break;
case MACHO_MAGIC64: // 64-bit LE
size = macho_header_t.sizeof;
o.status |= MACHO_S_64;
o.status |= MACHO_IS_64;
break;
case MACHO_CIGAM: // 32-bit BE
size = macho_header_t.sizeof;
o.status |= AdbgObjectInternalFlags.reversed;
break;
case MACHO_CIGAM64: // 64-bit BE
size = macho_header_t.sizeof;
o.status |= AdbgObjectInternalFlags.reversed | MACHO_S_64;
o.status |= AdbgObjectInternalFlags.reversed | MACHO_IS_64;
break;
case MACHO_FATMAGIC: // Fat LE
size = macho_fat_header_t.sizeof;
o.status |= MACHO_S_FAT;
o.status |= MACHO_IS_FAT;
break;
case MACHO_FATCIGAM: // Fat BE
size = macho_fat_header_t.sizeof;
o.status |= AdbgObjectInternalFlags.reversed | MACHO_S_FAT;
o.status |= AdbgObjectInternalFlags.reversed | MACHO_IS_FAT;
break;
default: // Unless loader gave a new signature?
return adbg_oops(AdbgError.objectMalformed);
Expand All @@ -462,9 +559,8 @@ int adbg_object_macho_load(adbg_object_t *o, uint magic) {

// If fields need to be swapped
with (cast(internal_macho_t*)o.internal)
if (o.status & (AdbgObjectInternalFlags.reversed | MACHO_S_FAT)) {
if (o.status & (AdbgObjectInternalFlags.reversed | MACHO_IS_FAT)) {
fat_header.nfat_arch = adbg_bswap32(fat_header.nfat_arch);

} else if (o.status & AdbgObjectInternalFlags.reversed) {
header.cputype = adbg_bswap32(header.cputype);
header.subtype = adbg_bswap32(header.subtype);
Expand All @@ -485,12 +581,16 @@ void adbg_object_macho_unload(adbg_object_t *o) {
free(o.internal);
}

int adbg_object_macho_is_64bit(adbg_object_t *o) {
return o.status & MACHO_IS_64;
}

//
// Fat Mach-O util functions
//

int adbg_object_macho_is_fat(adbg_object_t *o) {
return o ? o.status & MACHO_S_FAT : 0;
return o.status & MACHO_IS_FAT;
}

macho_fat_header_t* adbg_object_macho_fat_header(adbg_object_t *o) {
Expand All @@ -514,7 +614,7 @@ macho_fat_arch_entry_t* adbg_object_macho_fat_arch(adbg_object_t *o, size_t inde
adbg_oops(AdbgError.uninitiated);
return null;
}
if ((o.status & MACHO_S_FAT) == 0) {
if ((o.status & MACHO_IS_FAT) == 0) {
adbg_oops(AdbgError.unavailable);
return null;
}
Expand Down Expand Up @@ -586,7 +686,7 @@ macho_load_command_t* adbg_object_macho_load_command(adbg_object_t *o, size_t in
adbg_oops(AdbgError.uninitiated);
return null;
}
if (o.status & MACHO_S_FAT) {
if (o.status & MACHO_IS_FAT) {
adbg_oops(AdbgError.unavailable);
return null;
}
Expand All @@ -609,7 +709,7 @@ macho_load_command_t* adbg_object_macho_load_command(adbg_object_t *o, size_t in
adbg_oops(AdbgError.crt);
return null;
}
size_t cmdoff = o.status & MACHO_S_64 ? macho_header_t.sizeof + 4 : macho_header_t.sizeof;
size_t cmdoff = o.status & MACHO_IS_64 ? macho_header_t.sizeof + 4 : macho_header_t.sizeof;
if (adbg_object_read_at(o, cmdoff, commands, header.sizeofcmds))
return null;

Expand Down Expand Up @@ -641,6 +741,59 @@ macho_load_command_t* adbg_object_macho_load_command(adbg_object_t *o, size_t in
return command;
}

void* adbg_object_macho_segment_section(adbg_object_t *o, macho_load_command_t *c, size_t index) {
if (o == null || c == null) {
adbg_oops(AdbgError.invalidArgument);
return null;
}
if (o.internal == null) {
adbg_oops(AdbgError.uninitiated);
return null;
}
if (o.status & MACHO_IS_FAT) {
adbg_oops(AdbgError.unavailable);
return null;
}

//TODO: Swap fields

switch (c.cmd) {
case MACHO_LC_SEGMENT:
macho_segment_command_t *seg = cast(macho_segment_command_t*)c;

if (index > seg.nsects) {
adbg_oops(AdbgError.indexBounds);
return null;
}

macho_section_t *section = cast(macho_section_t*)
(cast(void*)seg + macho_segment_command_t.sizeof) + index;
if (adbg_bits_ptr_outside(section, c, c.cmdsize)) {
adbg_oops(AdbgError.offsetBounds);
return null;
}
return section;
case MACHO_LC_SEGMENT_64:
macho_segment_command_64_t *seg64 = cast(macho_segment_command_64_t*)c;

if (index > seg64.nsects) {
adbg_oops(AdbgError.indexBounds);
return null;
}

macho_section64_t *section64 = cast(macho_section64_t*)
(cast(void*)seg64 + macho_segment_command_64_t.sizeof) + index;
if (adbg_bits_ptr_outside(section64, c, c.cmdsize)) {
adbg_oops(AdbgError.offsetBounds);
return null;
}
return section64;
default:
adbg_oops(AdbgError.unavailable);
return null;
}
}

const(char) *adbg_object_macho_magic_string(uint signature) {
switch (signature) {
case MACHO_MAGIC: return "MACHO_MAGIC";
Expand Down Expand Up @@ -909,6 +1062,6 @@ const(char)* adbg_object_macho_kind_string(adbg_object_t *o) {

internal_macho_t *internal = cast(internal_macho_t*)o.internal;

if (o.status & MACHO_S_FAT) return `Fat Executable`;
if (o.status & MACHO_IS_FAT) return `Fat Executable`;
return adbg_object_macho_filetype_string(internal.header.filetype);
}

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