https://bitbucket.org/hudson/magic-lantern
Tip revision: 3c8ed7d6cda1a2c21294add1866d7d3f47dc0941 authored by alex@thinkpad on 24 September 2018, 10:00:01 UTC
io_trace: fix crash with CONFIG_QEMU
io_trace: fix crash with CONFIG_QEMU
Tip revision: 3c8ed7d
patch.c
/* Memory patching */
#include <dryos.h>
#include <menu.h>
#include <lvinfo.h>
#include <cache_hacks.h>
#include <patch.h>
#include <bmp.h>
#include <console.h>
#undef PATCH_DEBUG
#ifdef PATCH_DEBUG
#define dbg_printf(fmt,...) { printf(fmt, ## __VA_ARGS__); }
#else
#define dbg_printf(fmt,...) {}
#endif
#define MAX_PATCHES 32
#define MAX_MATRIX_PATCHES 16
#define MAX_LOGGING_HOOKS 32
/* for patching a single 32-bit integer (RAM or ROM, data or code) */
struct patch
{
uint32_t* addr; /* first memory address to patch (RAM or ROM) */
uint32_t backup; /* old value (to undo the patch) */
uint32_t patched_value; /* value after patching */
const char * description; /* will be displayed in the menu as help text */
unsigned is_instruction: 1; /* if 1, we have patched an instruction (needs extra care with the instruction cache) */
};
/* for patching an array or a matrix of related memory addresses */
struct matrix_patch
{
uint32_t* addr; /* first memory address to patch (RAM data only) */
uint16_t num_columns; /* how many columns in the matrix (1 = a single column) */
uint16_t col_size; /* offset until the next memory address, in bytes */
uint16_t num_rows; /* how many rows do we have? (1 = a single row = a simple array) */
uint16_t row_size; /* if patching a matrix of values: offset until the next row, in bytes */
uint32_t* backups; /* user-supplied storage for backup (must be uint32_t backup[num_columns*num_rows]) */
uint32_t patch_mask; /* what bits are actually used (both when reading original and writing patched value) */
uint32_t patch_scaling; /* scaling factor for the old value (0x10000 = 1.0; 0 discards the old value, obviously) */
uint32_t patch_offset; /* offset added after scaling (if scaling factor is 0, this will be the new value of the patched bits) */
const char * description; /* will be displayed in the menu as help text */
uint16_t scroll_pos; /* internal, for menu navigation */
};
/* ASM code from Maqs */
/* logging hooks are always paired to a simple patch (that does the jump to this code) */
union logging_hook_code
{
struct
{
uint32_t arm_asm[11]; /* ARM ASM code for jumping to the logging function and back */
uint32_t reloc_insn; /* original instruction, relocated */
uint32_t jump_back; /* instruction to jump back to original code */
uint32_t addr; /* patched address (for identification) */
uint32_t fixup; /* for relocating instructions that do PC-relative addressing */
uint32_t logging_function; /* for long call */
};
uint32_t code[16];
};
static struct patch patches[MAX_PATCHES] = {{0}};
static int num_patches = 0;
static struct matrix_patch matrix_patches[MAX_MATRIX_PATCHES] = {{0}};
static int num_matrix_patches = 0;
/* at startup we don't have malloc, so we allocate it statically */
static union logging_hook_code logging_hooks[MAX_LOGGING_HOOKS];
/**
* Common routines
* ===============
*/
static char last_error[70];
static void check_cache_lock_still_needed();
static int patch_sync_cache(int also_data);
/* re-apply the ROM (cache) patches */
/* call this after you have flushed the caches, for example */
int _reapply_cache_patches();
/* lock or unlock the cache as needed */
static void cache_require(int lock)
{
#ifdef CONFIG_QEMU
return;
#endif
if (lock)
{
if (!cache_locked())
{
printf("Locking cache\n");
cache_lock();
}
}
else
{
printf("Unlocking cache\n");
cache_unlock();
}
}
static int patch_sync_cache(int also_data)
{
#ifdef CONFIG_QEMU
return 0;
#endif
int err = 0;
int locked = cache_locked();
if (locked)
{
/* without this, reading from ROM right away may return the value patched in the I-Cache (5D2) */
/* as a result, ROM patches may not be restored */
cache_unlock();
}
if (also_data)
{
dbg_printf("Syncing caches...\n");
sync_caches();
}
else
{
dbg_printf("Flushing ICache...\n");
flush_i_cache();
}
if (locked)
{
cache_lock();
err = _reapply_cache_patches();
}
return err;
}
/* low-level routines */
static uint32_t read_value(uint32_t* addr, int is_instruction)
{
#ifdef CONFIG_QEMU
goto read_from_ram;
#endif
uint32_t cached_value;
if (is_instruction && IS_ROM_PTR(addr) && cache_locked()
&& cache_is_patchable((uint32_t)addr, TYPE_ICACHE, &cached_value) == 2)
{
/* return the value patched in the instruction cache */
dbg_printf("Read from ICache: %x -> %x\n", addr, cached_value);
return cached_value;
}
if (is_instruction)
{
/* when patching RAM instructions, the cached value might be incorrect - get it directly from RAM */
addr = UNCACHEABLE(addr);
}
if (IS_ROM_PTR(addr))
{
dbg_printf("Read from ROM: %x -> %x\n", addr, MEM(addr));
}
#ifdef CONFIG_QEMU
read_from_ram:
#endif
/* trick required because we don't have unaligned memory access */
switch ((uintptr_t)addr & 3)
{
case 0b00:
return *(volatile uint32_t*) addr;
case 0b10:
return *(volatile uint16_t*) addr;
default:
return *(volatile uint8_t*) addr;
}
}
static int do_patch(uint32_t* addr, uint32_t value, int is_instruction)
{
dbg_printf("Patching %x from %x to %x\n", addr, read_value(addr, is_instruction), value);
#ifdef CONFIG_QEMU
goto write_to_ram;
#endif
if (IS_ROM_PTR(addr))
{
/* todo: check for conflicts (@g3gg0?) */
cache_require(1);
int cache_type = is_instruction ? TYPE_ICACHE : TYPE_DCACHE;
if (cache_is_patchable((uint32_t)addr, cache_type, 0))
{
cache_fake((uint32_t)addr, value, cache_type);
/* did it actually work? */
if (read_value(addr, is_instruction) != value)
{
return E_PATCH_CACHE_ERROR;
}
/* yes! */
return 0;
}
else
{
return E_PATCH_CACHE_COLLISION;
}
}
if (is_instruction)
{
/* when patching RAM instructions, bypass the data cache and write directly to RAM */
/* (will flush the instruction cache later) */
addr = UNCACHEABLE(addr);
}
#ifdef CONFIG_QEMU
write_to_ram:
#endif
/* trick required because we don't have unaligned memory access */
switch ((uintptr_t)addr & 3)
{
case 0b00:
*(volatile uint32_t*)addr = value;
break;
case 0b10:
*(volatile uint16_t*)addr = value;
break;
default:
*(volatile uint8_t*) addr = value;
break;
}
return 0;
}
static char * error_msg(int err)
{
static char msg[128];
/* there may be one or more error flags set */
msg[0] = 0;
if (err & E_PATCH_UNKNOWN_ERROR) STR_APPEND(msg, "UNKNOWN_ERROR,");
if (err & E_PATCH_ALREADY_PATCHED) STR_APPEND(msg, "ALREADY_PATCHED,");
if (err & E_PATCH_TOO_MANY_PATCHES) STR_APPEND(msg, "TOO_MANY_PATCHES,");
if (err & E_PATCH_OLD_VALUE_MISMATCH) STR_APPEND(msg, "OLD_VAL_MISMATCH,");
if (err & E_PATCH_CACHE_COLLISION) STR_APPEND(msg, "CACHE_COLLISION,");
if (err & E_PATCH_CACHE_ERROR) STR_APPEND(msg, "CACHE_ERROR,");
if (err & E_PATCH_REG_NOT_FOUND) STR_APPEND(msg, "REG_NOT_FOUND,");
if (err & E_UNPATCH_NOT_PATCHED) STR_APPEND(msg, "NOT_PATCHED,");
if (err & E_UNPATCH_OVERWRITTEN) STR_APPEND(msg, "OVERWRITTEN,");
if (err & E_UNPATCH_REG_NOT_FOUND) STR_APPEND(msg, "REG_NOT_FOUND,");
/* remove last comma */
int len = strlen(msg);
if (len) msg[len-1] = 0;
return msg;
}
/**
* Simple patches
* ==============
*/
static uint32_t get_patch_current_value(struct patch * p)
{
return read_value(p->addr, p->is_instruction);
}
static int patch_memory_work(
uintptr_t _addr,
uint32_t old_value,
uint32_t new_value,
uint32_t is_instruction,
const char * description
)
{
uint32_t* addr = (uint32_t*)_addr;
int err = E_PATCH_OK;
/* ensure thread safety */
uint32_t old_int = cli();
dbg_printf("patch_memory_work(%x)\n", addr);
/* is this address already patched? refuse to patch it twice */
for (int i = 0; i < num_patches; i++)
{
if (patches[i].addr == addr)
{
err = E_PATCH_ALREADY_PATCHED;
goto end;
}
}
/* do we have room for a new patch? */
if (num_patches >= COUNT(patches))
{
err = E_PATCH_TOO_MANY_PATCHES;
goto end;
}
/* fill metadata */
patches[num_patches].addr = addr;
patches[num_patches].patched_value = new_value;
patches[num_patches].is_instruction = is_instruction;
patches[num_patches].description = description;
/* are we patching the right thing? */
uint32_t old = get_patch_current_value(&patches[num_patches]);
/* safety check */
if (old != old_value)
{
err = E_PATCH_OLD_VALUE_MISMATCH;
goto end;
}
/* save backup value */
patches[num_patches].backup = old;
/* checks done, backups saved, now patch */
err = do_patch(patches[num_patches].addr, new_value, is_instruction);
if (err) goto end;
/* RAM instructions are patched in RAM (to minimize collisions and only lock down the cache when needed),
* but we need to clear the cache and re-apply any existing ROM patches */
if (is_instruction && !IS_ROM_PTR(addr))
{
err = patch_sync_cache(0);
}
num_patches++;
end:
if (err)
{
snprintf(last_error, sizeof(last_error), "Patch error at %x (%s)", addr, error_msg(err));
puts(last_error);
}
sei(old_int);
return err;
}
static int is_patch_still_applied(int p)
{
uint32_t current = get_patch_current_value(&patches[p]);
uint32_t patched = patches[p].patched_value;
return (current == patched);
}
static int reapply_cache_patch(int p)
{
uint32_t current = get_patch_current_value(&patches[p]);
uint32_t patched = patches[p].patched_value;
if (current != patched)
{
void* addr = patches[p].addr;
dbg_printf("Re-applying %x -> %x (changed to %x)\n", addr, patched, current);
cache_fake((uint32_t) addr, patched, patches[p].is_instruction ? TYPE_ICACHE : TYPE_DCACHE);
/* did it actually work? */
if (read_value(addr, patches[p].is_instruction) != patched)
{
return E_PATCH_CACHE_ERROR;
}
}
return 0;
}
int _reapply_cache_patches()
{
#ifdef CONFIG_QEMU
return 0;
#endif
int err = 0;
/* this function is also public */
uint32_t old_int = cli();
for (int i = 0; i < num_patches; i++)
{
if (IS_ROM_PTR(patches[i].addr))
{
err |= reapply_cache_patch(i);
}
}
sei(old_int);
return err;
}
static void check_cache_lock_still_needed()
{
#ifdef CONFIG_QEMU
return;
#endif
if (!cache_locked())
{
return;
}
/* do we still need the cache locked? */
int rom_patches = 0;
for (int i = 0; i < num_patches; i++)
{
if (IS_ROM_PTR(patches[i].addr))
{
rom_patches = 1;
break;
}
}
if (!rom_patches)
{
/* nope, we don't */
cache_require(0);
}
}
/* forward reference */
static int unpatch_memory_matrix(uintptr_t _addr, uint32_t old_int);
int unpatch_memory(uintptr_t _addr)
{
uint32_t* addr = (uint32_t*) _addr;
int err = E_UNPATCH_OK;
uint32_t old_int = cli();
dbg_printf("unpatch_memory(%x)\n", addr);
/* find the patch in our data structure */
int p = -1;
for (int i = 0; i < num_patches; i++)
{
if (patches[i].addr == addr)
{
p = i;
break;
}
}
if (p < 0)
{
/* patch not found, let's look it up in the matrix patches */
return unpatch_memory_matrix(_addr, old_int);
}
/* is the patch still applied? */
if (!is_patch_still_applied(p))
{
err = E_UNPATCH_OVERWRITTEN;
goto end;
}
#ifndef CONFIG_QEMU
/* not needed for ROM patches - there we will re-apply all the remaining ones from scratch */
/* (slower, but old reverted patches should no longer give collisions) */
if (!IS_ROM_PTR(addr))
#endif
{
err = do_patch(patches[p].addr, patches[p].backup, patches[p].is_instruction);
if (err) goto end;
}
/* remove from our data structure (shift the other array items) */
for (int i = p + 1; i < num_patches; i++)
{
patches[i-1] = patches[i];
}
num_patches--;
/* also look in up in the logging hooks, and zero it out if found */
for (int i = 0; i < MAX_LOGGING_HOOKS; i++)
{
if (logging_hooks[i].addr == _addr)
{
memset(&logging_hooks[i], 0, sizeof(union logging_hook_code));
}
}
if (IS_ROM_PTR(addr))
{
/* unlock and re-apply only the remaining patches */
cache_unlock();
cache_lock();
err = _reapply_cache_patches();
}
else if (patches[p].is_instruction)
{
err = patch_sync_cache(0);
}
check_cache_lock_still_needed();
end:
if (err)
{
snprintf(last_error, sizeof(last_error), "Unpatch error at %x (%s)", addr, error_msg(err));
puts(last_error);
}
sei(old_int);
return err;
}
int patch_memory(
uintptr_t addr,
uint32_t old_value,
uint32_t new_value,
const char * description
)
{
return patch_memory_work(addr, old_value, new_value, 0, description);
}
int patch_instruction(
uintptr_t addr,
uint32_t old_value,
uint32_t new_value,
const char * description
)
{
return patch_memory_work(addr, old_value, new_value, 1, description);
}
/**
* Engio register lists
* ====================
*/
int patch_engio_list(uint32_t * engio_list, uint32_t patched_register, uint32_t patched_value, const char * description)
{
while (*engio_list != 0xFFFFFFFF)
{
uint32_t reg = *engio_list;
if (reg == patched_register)
{
/* evil hack that relies on unused LSB bits on the register address */
/* this will cause Canon code to ignore this register and keep our patched value */
*(engio_list) = patched_register + 1;
return patch_memory((uintptr_t)(engio_list+1), engio_list[1], patched_value, description);
}
engio_list += 2;
}
return E_PATCH_REG_NOT_FOUND;
}
int unpatch_engio_list(uint32_t * engio_list, uint32_t patched_register)
{
while (*engio_list != 0xFFFFFFFF)
{
uint32_t reg = *engio_list;
if (reg == patched_register + 1)
{
*(engio_list) = patched_register;
return unpatch_memory((uintptr_t)(engio_list+1));
}
engio_list += 2;
}
return E_UNPATCH_REG_NOT_FOUND;
}
/**
* Matrix patches
* ==============
*/
static void* get_matrix_patch_addr(struct matrix_patch * p, int row_index, int col_index)
{
return (void*)p->addr + row_index * p->row_size + col_index * p->col_size;
}
enum masked {NOT_MASKED, MASKED};
static uint32_t get_matrix_patch_current_value(struct matrix_patch * p, int row_index, int col_index, enum masked masked)
{
void* addr = get_matrix_patch_addr(p, row_index, col_index);
uint32_t raw_value = read_value(addr, 0);
if (masked == MASKED)
{
return raw_value & p->patch_mask;
}
else
{
return raw_value;
}
}
static uint32_t get_matrix_patch_backup_value(struct matrix_patch * p, int row_index, int col_index, enum masked masked)
{
int linear_index = COERCE(row_index * p->num_columns + col_index, 0, p->num_rows * p->num_columns - 1);
uint32_t ans = p->backups[linear_index];
if (masked == MASKED)
{
ans &= p->patch_mask;
}
return ans;
}
static void set_matrix_patch_backup_value(struct matrix_patch * p, int row_index, int col_index, uint32_t value)
{
dbg_printf("Backup %x[%d][%d] = %x\n", p->addr, row_index, col_index, value);
int linear_index = COERCE(row_index * p->num_columns + col_index, 0, p->num_rows * p->num_columns - 1);
p->backups[linear_index] = value;
}
static uint32_t get_matrix_patch_new_value(struct matrix_patch * p, int row_index, int col_index)
{
if (p->patch_scaling == 0)
{
return p->patch_offset & p->patch_mask;
}
else
{
uint32_t old = get_matrix_patch_backup_value(p, row_index, col_index, MASKED);
uint32_t new = (uint64_t) old * (uint64_t) p->patch_scaling / (uint64_t) 0x10000 + p->patch_offset;
dbg_printf("Scaling %x[%x][%x] from %x to %x f=0x%x/0x10000\n", p->addr, row_index, col_index, old, new & p->patch_mask, p->patch_scaling);
return new & p->patch_mask;
}
}
int patch_memory_matrix(
uintptr_t _addr,
int num_columns,
int col_size,
int num_rows,
int row_size,
uint32_t check_mask,
uint32_t check_value,
uint32_t patch_mask,
uint32_t patch_scaling,
uint32_t patch_offset,
uint32_t* backup_storage,
const char * description
)
{
uint32_t* addr = (uint32_t*)_addr;
int err = E_PATCH_OK;
/* ensure thread safety */
uint32_t old_int = cli();
/* is this address already patched? refuse to patch it twice */
for (int i = 0; i < num_matrix_patches; i++)
{
if (matrix_patches[i].addr == addr)
{
err = E_PATCH_ALREADY_PATCHED;
goto end;
}
/* todo: check matrices too */
}
/* do we have room for a new patch? */
if (num_matrix_patches >= COUNT(matrix_patches))
{
err = E_PATCH_TOO_MANY_PATCHES;
goto end;
}
/* fill metadata */
matrix_patches[num_matrix_patches].addr = addr;
matrix_patches[num_matrix_patches].num_rows = num_rows;
matrix_patches[num_matrix_patches].row_size = row_size;
matrix_patches[num_matrix_patches].num_columns = num_columns;
matrix_patches[num_matrix_patches].col_size = col_size;
matrix_patches[num_matrix_patches].patch_mask = patch_mask;
matrix_patches[num_matrix_patches].patch_scaling = patch_scaling;
matrix_patches[num_matrix_patches].patch_offset = patch_offset;
matrix_patches[num_matrix_patches].backups = backup_storage;
matrix_patches[num_matrix_patches].description = description;
/* are we patching the right thing? */
/* and while we are at it, save backup values too */
for (int r = 0; r < num_rows; r++)
{
for (int c = 0; c < num_columns; c++)
{
uint32_t old = get_matrix_patch_current_value(&matrix_patches[num_matrix_patches], r, c, NOT_MASKED);
/* safety check */
if ((old & check_mask) != (check_value & check_mask))
{
err = E_PATCH_OLD_VALUE_MISMATCH;
goto end;
}
/* save backup value */
set_matrix_patch_backup_value(&matrix_patches[num_matrix_patches], r, c, old);
}
}
/* checks done, backups saved, now patch */
for (int r = 0; r < num_rows; r++)
{
for (int c = 0; c < num_columns; c++)
{
void* adr = get_matrix_patch_addr(&matrix_patches[num_matrix_patches], r, c);
uint32_t old = get_matrix_patch_current_value(&matrix_patches[num_matrix_patches], r, c, NOT_MASKED);
uint32_t patch_value = get_matrix_patch_new_value(&matrix_patches[num_matrix_patches], r, c);
uint32_t new = (old & ~patch_mask) | (patch_value & patch_mask);
do_patch(adr, new, 0);
}
}
num_matrix_patches++;
end:
if (err)
{
snprintf(last_error, sizeof(last_error), "Patch error at %x (%s)", addr, error_msg(err));
puts(last_error);
}
sei(old_int);
return err;
}
static int is_matrix_patch_still_applied(int p)
{
int num_rows = matrix_patches[p].num_rows;
int num_columns = matrix_patches[p].num_columns;
for (int r = 0; r < num_rows; r++)
{
for (int c = 0; c < num_columns; c++)
{
uint32_t current = get_matrix_patch_current_value(&matrix_patches[p], r, c, MASKED);
uint32_t patched = get_matrix_patch_new_value(&matrix_patches[p], r, c);
if (current != patched) return 0;
}
}
return 1;
}
/* note: this is always called with interrupts disabled */
static int unpatch_memory_matrix(uintptr_t _addr, uint32_t old_int)
{
uint32_t* addr = (uint32_t*) _addr;
int err = E_UNPATCH_OK;
int p = -1;
for (int i = 0; i < num_matrix_patches; i++)
{
if (matrix_patches[i].addr == addr)
{
p = i;
break;
}
}
if (p < 0)
{
err = E_UNPATCH_NOT_PATCHED;
goto end;
}
/* is the patch still applied? */
if (!is_matrix_patch_still_applied(p))
{
err = E_UNPATCH_OVERWRITTEN;
goto end;
}
/* undo the patch */
int num_rows = matrix_patches[p].num_rows;
int num_columns = matrix_patches[p].num_columns;
for (int r = 0; r < num_rows; r++)
{
for (int c = 0; c < num_columns; c++)
{
void* adr = get_matrix_patch_addr(&matrix_patches[p], r, c);
uint32_t old = get_matrix_patch_current_value(&matrix_patches[p], r, c, NOT_MASKED);
uint32_t backup = get_matrix_patch_backup_value(&matrix_patches[p], r, c, MASKED);
uint32_t patch_mask = matrix_patches[p].patch_mask;
uint32_t new = (old & ~patch_mask) | backup;
do_patch(adr, new, 0);
}
}
/* remove from our data structure (shift the other array items) */
for (int i = p + 1; i < num_matrix_patches; i++)
{
matrix_patches[i-1] = matrix_patches[i];
}
num_matrix_patches--;
end:
if (err)
{
snprintf(last_error, sizeof(last_error), "Unpatch error at %x (%s)", addr, error_msg(err));
puts(last_error);
}
sei(old_int);
return err;
}
int patch_memory_ex(
uintptr_t addr,
uint32_t check_mask,
uint32_t check_value,
uint32_t patch_mask,
uint32_t patch_scaling,
uint32_t patch_offset,
const char * description
)
{
return patch_memory_matrix(addr, 1, 0, 1, 0, check_mask, check_value, patch_mask, patch_scaling, patch_offset, 0, description);
}
int patch_memory_array(
uintptr_t addr,
int num_items,
int item_size,
uint32_t check_mask,
uint32_t check_value,
uint32_t patch_mask,
uint32_t patch_scaling,
uint32_t patch_offset,
uint32_t* backup_storage,
const char * description
)
{
return patch_memory_matrix(addr, num_items, item_size, 1, 0, check_mask, check_value, patch_mask, patch_scaling, patch_offset, backup_storage, description);
}
/**
* Logging hooks
* =============
*/
#define REG_PC 15
#define LOAD_MASK 0x0C000000
#define LOAD_INSTR 0x04000000
static uint32_t reloc_instr(uint32_t pc, uint32_t new_pc, uint32_t fixup)
{
uint32_t instr = MEM(pc);
uint32_t load = instr & LOAD_MASK;
// Check for load from %pc
if( load == LOAD_INSTR )
{
uint32_t reg_base = (instr >> 16) & 0xF;
int32_t offset = (instr >> 0) & 0xFFF;
if( reg_base != REG_PC )
return instr;
// Check direction bit and flip the sign
if( (instr & (1<<23)) == 0 )
offset = -offset;
// Compute the destination, including the change in pc
uint32_t dest = pc + offset + 8;
// Find the data that is being used and
// compute a new offset so that it can be
// accessed from the relocated space.
uint32_t data = MEM(dest);
int32_t new_offset = fixup - new_pc - 8;
uint32_t new_instr = 0
| ( 1<<23 ) /* our fixup is always forward */
| ( instr & ~0xFFF ) /* copy old instruction, without offset */
| ( new_offset & 0xFFF ) /* replace offset */
;
// Copy the data to the offset location
MEM(fixup) = data;
return new_instr;
}
return instr;
}
static int check_jump_range(uint32_t pc, uint32_t dest)
{
/* shift offset by 2+6 bits to handle the sign bit */
int32_t offset = (B_INSTR(pc, dest) & 0x00FFFFFF) << 8;
/* compute the destination from the jump and compare to the original */
uint32_t new_dest = ((((uint64_t)pc + 8) << 6) + offset) >> 6;
if (dest != new_dest)
{
printf("Jump range error: %x -> %x\n", pc, dest);
return 0;
}
return 1;
}
int patch_hook_function(uintptr_t addr, uint32_t orig_instr, patch_hook_function_cbr logging_function, const char * description)
{
int err = 0;
/* ensure thread safety */
uint32_t old_int = cli();
/* find a free slot in logging_hooks */
int logging_slot = -1;
for (int i = 0; i < COUNT(logging_hooks); i++)
{
if (logging_hooks[i].addr == 0)
{
logging_slot = i;
break;
}
}
if (logging_slot < 0)
{
snprintf(last_error, sizeof(last_error), "Patch error at %x (no logging slot)", addr);
puts(last_error);
err = E_PATCH_TOO_MANY_PATCHES;
goto end;
}
union logging_hook_code * hook = &logging_hooks[logging_slot];
/* check the jumps we are going to use */
/* fixme: use long jumps? */
if (!check_jump_range((uint32_t) &hook->reloc_insn, (uint32_t) addr + 4) ||
!check_jump_range((uint32_t) addr, (uint32_t) hook))
{
snprintf(last_error, sizeof(last_error), "Patch error at %x (jump out of range)", addr);
puts(last_error);
err = E_PATCH_UNKNOWN_ERROR;
goto end;
}
/* create the logging code */
*hook = (union logging_hook_code) { .code = {
0xe92d5fff, /* STMFD SP!, {R0-R12,LR} ; save all regs to stack */
0xe10f0000, /* MRS R0, CPSR ; save CPSR (flags) */
0xe92d0001, /* STMFD SP!, {R0} ; to stack */
0xe28d0004, /* ADD R0, SP, #4 ; pass them to logging function as first arg */
0xe28d103c, /* ADD R1, SP, #60 ; pass stack pointer to logging function */
0xe59f2018, /* LDR R2, [PC,#24] ; pass patched address to logging function */
0xe1a0e00f, /* MOV LR, PC ; setup return address for long call */
0xe59ff018, /* LDR PC, [PC,#24] ; long call to logging_function */
0xe8bd0001, /* LDMFD SP!, {R0} ; restore CPSR */
0xe128f000, /* MSR CPSR_f, R0 ; (flags only) from stack */
0xe8bd5fff, /* LDMFD SP!, {R0-R12,LR} ; restore regs */
reloc_instr(
addr, /* ; relocate the original instruction */
(uint32_t) &hook->reloc_insn, /* ; from the patched address */
(uint32_t) &hook->fixup /* ; (it might need a fixup) */
),
B_INSTR(&hook->jump_back, addr + 4),/* ; jump back to original code */
addr, /* ; patched address (for identification) */
hook->fixup, /* ; this is updated by reloc_instr */
(uint32_t) logging_function,
}};
/* since we have modified some code in RAM, sync the caches */
patch_sync_cache(1);
/* patch the original instruction to jump to the logging code */
err = patch_instruction(addr, orig_instr, B_INSTR(addr, hook), description);
if (err)
{
/* something went wrong? */
memset(hook, 0, sizeof(union logging_hook_code));
goto end;
}
end:
sei(old_int);
return err;
}
/**
* GUI code
* ========
**/
static MENU_UPDATE_FUNC(patch_update)
{
int p = (int) entry->priv;
if (p < 0 || p >= num_patches)
{
entry->shidden = 1;
return;
}
/* long description */
MENU_SET_HELP("%s.", patches[p].description);
/* short description: assume the long description is formatted as "module_name: it does this and that" */
/* => extract module_name and display it as short description */
char short_desc[16];
snprintf(short_desc, sizeof(short_desc), "%s", patches[p].description);
char* sep = strchr(short_desc, ':');
if (sep) *sep = 0;
MENU_SET_RINFO("%s", short_desc);
/* ROM patches are considered invasive, display them with red icon */
MENU_SET_ICON(IS_ROM_PTR(patches[p].addr) ? MNI_RECORD : MNI_ON, 0);
char name[20];
snprintf(name, sizeof(name), "%s: %X", patches[p].is_instruction ? "Code" : "Data", patches[p].addr);
MENU_SET_NAME("%s", name);
int val = get_patch_current_value(&patches[p]);
int backup = patches[p].backup;
/* patch value: do we have enough space to print before and after? */
if ((val & 0xFFFF0000) == 0 && (backup & 0xFFFF0000) == 0)
{
MENU_SET_VALUE("%X -> %X", backup, val);
}
else
{
MENU_SET_VALUE("%X", val);
}
/* some detailed info */
void* addr = patches[p].addr;
MENU_SET_WARNING(MENU_WARN_INFO, "0x%X: 0x%X -> 0x%X.", addr, backup, val);
/* was this patch overwritten by somebody else? */
if (!is_patch_still_applied(p))
{
MENU_SET_WARNING(MENU_WARN_NOT_WORKING,
"Patch %x overwritten (expected %x, got %x).",
patches[p].addr, patches[p].patched_value, get_patch_current_value(&patches[p])
);
}
}
static MENU_SELECT_FUNC(matrix_patch_scroll)
{
int p = (int) priv;
if (p < 0 || p >= num_matrix_patches)
return;
int scroll_pos = matrix_patches[p].scroll_pos;
menu_numeric_toggle(&scroll_pos, delta, 0, matrix_patches[p].num_rows * matrix_patches[p].num_columns - 1);
matrix_patches[p].scroll_pos = scroll_pos;
}
/* todo: common code with patch_update? */
static MENU_UPDATE_FUNC(matrix_patch_update)
{
int p = (int) entry->priv;
if (p < 0 || p >= num_matrix_patches)
{
entry->shidden = 1;
return;
}
/* long description */
MENU_SET_HELP("%s.", matrix_patches[p].description);
/* short description: assume the long description is formatted as "module_name: it does this and that" */
/* => extract module_name and display it as short description */
char short_desc[16];
snprintf(short_desc, sizeof(short_desc), "%s", matrix_patches[p].description);
char* sep = strchr(short_desc, ':');
if (sep) *sep = 0;
MENU_SET_RINFO("%s", short_desc);
/* ROM matrix_patches are considered invasive, display them with red icon */
MENU_SET_ICON(IS_ROM_PTR(matrix_patches[p].addr) ? MNI_RECORD : MNI_ON, 0);
char name[20];
snprintf(name, sizeof(name), "Array: %X");
int row = (matrix_patches[p].scroll_pos / matrix_patches[p].num_columns) % matrix_patches[p].num_rows;
int col = matrix_patches[p].scroll_pos % matrix_patches[p].num_columns;
if (matrix_patches[p].scroll_pos == 0)
{
if (matrix_patches[p].num_rows > 1)
{
STR_APPEND(name, " "SYM_TIMES" %d", matrix_patches[p].num_rows);
}
if (matrix_patches[p].num_columns > 1)
{
STR_APPEND(name, " "SYM_TIMES" %d", matrix_patches[p].num_columns);
}
}
else
{
if (matrix_patches[p].num_rows > 1)
{
STR_APPEND(name, " [%d]", row);
}
if (matrix_patches[p].num_columns > 1)
{
STR_APPEND(name, " [%d]", col);
}
}
MENU_SET_NAME("%s", name);
/* if 16-bit is enough, show only that */
int type_mask = 0xFFFF;
if (matrix_patches[p].patch_mask & 0xFFFF0000) type_mask = 0xFFFFFFFF;
int val = get_matrix_patch_current_value(&matrix_patches[p], row, col, NOT_MASKED) & type_mask;
int backup = get_matrix_patch_backup_value(&matrix_patches[p], row, col, NOT_MASKED) & type_mask;
/* patch value: do we have enough space to print before and after? */
if ((val & 0xFFFF0000) == 0 && (backup & 0xFFFF0000) == 0)
{
MENU_SET_VALUE("%X -> %X", backup, val);
}
else
{
MENU_SET_VALUE("%X", val);
}
/* some detailed info */
void* addr = get_matrix_patch_addr(&matrix_patches[p], row, col);
MENU_SET_WARNING(MENU_WARN_INFO, "0x%X: 0x%X -> 0x%X, mask %x.", addr, backup, val, matrix_patches[p].patch_mask);
/* was this patch overwritten by somebody else? */
if (!is_matrix_patch_still_applied(p))
{
MENU_SET_WARNING(MENU_WARN_NOT_WORKING, "This patch was overwritten, probably by Maxwell's demon.");
}
}
/* forward reference */
static struct menu_entry patch_menu[];
#define SIMPLE_PATCH_MENU_ENTRY(i) patch_menu[0].children[i]
#define MATRIX_PATCH_MENU_ENTRY(i) patch_menu[0].children[(i)+MAX_PATCHES]
static MENU_UPDATE_FUNC(patches_update)
{
int ram_patches = 0;
int rom_patches = 0;
int errors = 0;
for (int i = 0; i < MAX_PATCHES; i++)
{
if (i < num_patches)
{
if (IS_ROM_PTR(patches[i].addr))
{
rom_patches++;
}
else
{
ram_patches++;
}
SIMPLE_PATCH_MENU_ENTRY(i).shidden = 0;
if (!is_patch_still_applied(i))
{
snprintf(last_error, sizeof(last_error),
"Patch %x overwritten (expected %x, current value %x).",
patches[i].addr, patches[i].patched_value, get_patch_current_value(&patches[i])
);
puts(last_error);
errors++;
}
}
else
{
SIMPLE_PATCH_MENU_ENTRY(i).shidden = 1;
}
}
for (int i = 0; i < MAX_MATRIX_PATCHES; i++)
{
if (i < num_matrix_patches)
{
if (IS_ROM_PTR(matrix_patches[i].addr))
{
rom_patches++;
}
else
{
ram_patches++;
}
MATRIX_PATCH_MENU_ENTRY(i).shidden = 0;
if (!is_matrix_patch_still_applied(i))
{
snprintf(last_error, sizeof(last_error), "Patch %x overwritten, probably by Maxwell's demon.");
puts(last_error);
errors++;
}
}
else
{
MATRIX_PATCH_MENU_ENTRY(i).shidden = 1;
}
}
if (ram_patches == 0 && rom_patches == 0)
{
MENU_SET_RINFO("None");
MENU_SET_ENABLED(0);
}
else
{
MENU_SET_ICON(MNI_SUBMENU, 1);
if (errors) MENU_SET_RINFO("%d ERR", errors);
if (rom_patches) MENU_APPEND_RINFO("%s%d ROM", info->rinfo[0] ? ", " : "", rom_patches);
if (ram_patches) MENU_APPEND_RINFO("%s%d RAM", info->rinfo[0] ? ", " : "", ram_patches);
}
if (last_error[0])
{
MENU_SET_ICON(MNI_RECORD, 0); /* red dot */
MENU_SET_WARNING(MENU_WARN_ADVICE, last_error);
}
else if (cache_locked())
{
MENU_SET_ICON(MNI_RECORD, 0); /* red dot */
MENU_SET_WARNING(MENU_WARN_ADVICE, "Cache is locked down (not exactly clean).");
}
}
#define PATCH_ENTRY(i) \
{ \
.name = "(empty)", \
.priv = (void*)i, \
.update = patch_update, \
.shidden = 1, \
}
#define MATRIX_PATCH_ENTRY(i) \
{ \
.name = "(empty)", \
.priv = (void*)i, \
.select = matrix_patch_scroll, \
.update = matrix_patch_update, \
.shidden = 1, \
}
static struct menu_entry patch_menu[] =
{
{
.name = "Memory patches",
.update = patches_update,
.select = menu_open_submenu,
.icon_type = IT_SUBMENU,
.help = "Show memory addresses patched in Canon code or data areas.",
.submenu_width = 710,
.children = (struct menu_entry[]) {
// for i in range(128): print " PATCH_ENTRY(%d)," % i
PATCH_ENTRY(0),
PATCH_ENTRY(1),
PATCH_ENTRY(2),
PATCH_ENTRY(3),
PATCH_ENTRY(4),
PATCH_ENTRY(5),
PATCH_ENTRY(6),
PATCH_ENTRY(7),
PATCH_ENTRY(8),
PATCH_ENTRY(9),
PATCH_ENTRY(10),
PATCH_ENTRY(11),
PATCH_ENTRY(12),
PATCH_ENTRY(13),
PATCH_ENTRY(14),
PATCH_ENTRY(15),
PATCH_ENTRY(16),
PATCH_ENTRY(17),
PATCH_ENTRY(18),
PATCH_ENTRY(19),
PATCH_ENTRY(20),
PATCH_ENTRY(21),
PATCH_ENTRY(22),
PATCH_ENTRY(23),
PATCH_ENTRY(24),
PATCH_ENTRY(25),
PATCH_ENTRY(26),
PATCH_ENTRY(27),
PATCH_ENTRY(28),
PATCH_ENTRY(29),
PATCH_ENTRY(30),
PATCH_ENTRY(31),
// for i in range(128): print " MATRIX_PATCH_ENTRY(%d)," % i
MATRIX_PATCH_ENTRY(0),
MATRIX_PATCH_ENTRY(1),
MATRIX_PATCH_ENTRY(2),
MATRIX_PATCH_ENTRY(3),
MATRIX_PATCH_ENTRY(4),
MATRIX_PATCH_ENTRY(5),
MATRIX_PATCH_ENTRY(6),
MATRIX_PATCH_ENTRY(7),
MATRIX_PATCH_ENTRY(8),
MATRIX_PATCH_ENTRY(9),
MATRIX_PATCH_ENTRY(10),
MATRIX_PATCH_ENTRY(11),
MATRIX_PATCH_ENTRY(12),
MATRIX_PATCH_ENTRY(13),
MATRIX_PATCH_ENTRY(14),
MATRIX_PATCH_ENTRY(15),
MENU_EOL,
}
}
};
static void patch_simple_init()
{
menu_add("Debug", patch_menu, COUNT(patch_menu));
}
INIT_FUNC("patch", patch_simple_init);