/* Capstone Disassembler Engine */
/* By David Hogarty, 2014 */
// the following must precede stdio (woo, thanks msft)
#if defined(_MSC_VER) && _MSC_VER < 1900
#define _CRT_SECURE_NO_WARNINGS
#define snprintf _snprintf
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <platform.h>
#include <capstone.h>
static csh handle;
struct platform {
cs_arch arch;
cs_mode mode;
unsigned char *code;
size_t size;
char *comment;
int syntax;
};
static char *hex_string(unsigned char *str, size_t len)
{
// returns a malloced string that has the hex version of the string in it
// null if failed to malloc
char *hex_out;
size_t i;
hex_out = (char *) malloc(len*2 + 1); // two ascii characters per input character, plus trailing null
if (!hex_out) { goto Exit; }
for (i = 0; i < len; ++i) {
snprintf(hex_out + (i*2), 2, "%02x", str[i]);
}
hex_out[len*2] = 0; // trailing null
Exit:
return hex_out;
}
static void snprint_insn_detail(char * buf, size_t * cur, size_t * left, cs_insn *ins)
{
size_t used = 0;
#define _this_printf(...) \
{ \
size_t used = 0; \
used = snprintf(buf + *cur, *left, __VA_ARGS__); \
*left -= used; \
*cur += used; \
}
cs_arm *arm;
int i;
// detail can be NULL on "data" instruction if SKIPDATA option is turned ON
if (ins->detail == NULL)
return;
arm = &(ins->detail->arm);
if (arm->op_count)
_this_printf("\top_count: %u\n", arm->op_count);
for (i = 0; i < arm->op_count; i++) {
cs_arm_op *op = &(arm->operands[i]);
switch((int)op->type) {
default:
break;
case ARM_OP_REG:
_this_printf("\t\toperands[%u].type: REG = %s\n", i, cs_reg_name(handle, op->reg));
break;
case ARM_OP_IMM:
_this_printf("\t\toperands[%u].type: IMM = 0x%x\n", i, op->imm);
break;
case ARM_OP_FP:
_this_printf("\t\toperands[%u].type: FP = %f\n", i, op->fp);
break;
case ARM_OP_MEM:
_this_printf("\t\toperands[%u].type: MEM\n", i);
if (op->mem.base != X86_REG_INVALID)
_this_printf("\t\t\toperands[%u].mem.base: REG = %s\n",
i, cs_reg_name(handle, op->mem.base));
if (op->mem.index != X86_REG_INVALID)
_this_printf("\t\t\toperands[%u].mem.index: REG = %s\n",
i, cs_reg_name(handle, op->mem.index));
if (op->mem.scale != 1)
_this_printf("\t\t\toperands[%u].mem.scale: %u\n", i, op->mem.scale);
if (op->mem.disp != 0)
_this_printf("\t\t\toperands[%u].mem.disp: 0x%x\n", i, op->mem.disp);
break;
case ARM_OP_PIMM:
_this_printf("\t\toperands[%u].type: P-IMM = %u\n", i, op->imm);
break;
case ARM_OP_CIMM:
_this_printf("\t\toperands[%u].type: C-IMM = %u\n", i, op->imm);
break;
}
if (op->shift.type != ARM_SFT_INVALID && op->shift.value) {
if (op->shift.type < ARM_SFT_ASR_REG) {
// shift with constant value
_this_printf("\t\t\tShift: %u = %u\n", op->shift.type, op->shift.value);
} else {
// shift with register
_this_printf("\t\t\tShift: %u = %s\n", op->shift.type,
cs_reg_name(handle, op->shift.value));
}
}
}
if (arm->cc != ARM_CC_AL && arm->cc != ARM_CC_INVALID) {
_this_printf("\tCode condition: %u\n", arm->cc);
}
if (arm->update_flags) {
_this_printf("\tUpdate-flags: True\n");
}
if (arm->writeback) {
_this_printf("\tWrite-back: True\n");
}
#undef _this_printf
}
static void print_insn_detail(cs_insn *ins)
{
char a_buf[2048];
size_t cur=0, left=2048;
snprint_insn_detail(a_buf, &cur, &left, ins);
printf("%s\n", a_buf);
}
struct invalid_code {
unsigned char *code;
size_t size;
char *comment;
};
#define MAX_INVALID_CODES 16
struct invalid_instructions {
cs_arch arch;
cs_mode mode;
char *platform_comment;
int num_invalid_codes;
struct invalid_code invalid_codes[MAX_INVALID_CODES];
};
static void test_invalids()
{
struct invalid_instructions invalids[] = {{
CS_ARCH_ARM,
CS_MODE_THUMB,
"Thumb",
1,
{{
(unsigned char *)"\xbd\xe8\x1e\xff",
4,
"invalid thumb2 pop because sp used and because both pc and lr are "
"present at the same time"
}},
}};
struct invalid_instructions * invalid = NULL;
uint64_t address = 0x1000;
cs_insn *insn;
int i;
int j;
size_t count;
printf("\nShould be invalid\n"
"-----------------\n");
for (i = 0; i < sizeof(invalids)/sizeof(invalids[0]); i++) {
cs_err err;
invalid = invalids + i;
err = cs_open(invalid->arch, invalid->mode, &handle);
if (err) {
printf("Failed on cs_open() with error returned: %u\n", err);
continue;
}
cs_option(handle, CS_OPT_DETAIL, CS_OPT_ON);
cs_option(handle, CS_OPT_SYNTAX, CS_OPT_SYNTAX_NOREGNAME);
for (j = 0; j < invalid->num_invalid_codes; ++j) {
struct invalid_code *invalid_code = NULL;
char *hex_str = NULL;
invalid_code = invalid->invalid_codes + j;
hex_str = hex_string(invalid_code->code, invalid_code->size);
printf("%s %s: %s\n", invalid->platform_comment, hex_str, invalid_code->comment);
free(hex_str);
count = cs_disasm(handle,
invalid_code->code, invalid_code->size, address, 0, &insn
);
if (count) {
size_t k;
printf(" ERROR:\n");
for (k = 0; k < count; k++) {
printf(" 0x%"PRIx64":\t%s\t%s\n",
insn[k].address, insn[k].mnemonic, insn[k].op_str);
print_insn_detail(&insn[k]);
}
cs_free(insn, count);
} else {
printf(" SUCCESS: invalid\n");
}
}
cs_close(&handle);
}
}
struct valid_code {
unsigned char *code;
size_t size;
uint32_t start_addr;
char *expected_out;
char *comment;
};
#define MAX_VALID_CODES 16
struct valid_instructions {
cs_arch arch;
cs_mode mode;
char *platform_comment;
int num_valid_codes;
struct valid_code valid_codes[MAX_VALID_CODES];
};
static void test_valids()
{
struct valid_instructions valids[] = {{
CS_ARCH_ARM,
CS_MODE_THUMB,
"Thumb",
3,
{{ (unsigned char *)"\x00\xf0\x26\xe8", 4, 0x352,
"0x352:\tblx\t#0x3a0\n"
"\top_count: 1\n"
"\t\toperands[0].type: IMM = 0x3a0\n",
"thumb2 blx with misaligned immediate"
}, { (unsigned char *)"\x05\xdd", 2, 0x1f0,
"0x1f0:\tble\t#0x1fe\n"
"\top_count: 1\n"
"\t\toperands[0].type: IMM = 0x1fe\n"
"\tCode condition: 14\n",
"thumb b cc with thumb-aligned target"
}, { (unsigned char *)"\xbd\xe8\xf0\x8f", 4, 0,
"0x0:\tpop.w\t{r4, r5, r6, r7, r8, r9, r10, r11, pc}\n"
"\top_count: 9\n"
"\t\toperands[0].type: REG = r4\n"
"\t\toperands[1].type: REG = r5\n"
"\t\toperands[2].type: REG = r6\n"
"\t\toperands[3].type: REG = r7\n"
"\t\toperands[4].type: REG = r8\n"
"\t\toperands[5].type: REG = r9\n"
"\t\toperands[6].type: REG = r10\n"
"\t\toperands[7].type: REG = r11\n"
"\t\toperands[8].type: REG = pc\n",
"thumb2 pop that should be valid"
},
}
}};
struct valid_instructions * valid = NULL;
uint64_t address = 0x1000;
cs_insn *insn;
int i;
int j;
size_t count;
for (i = 0; i < sizeof(valids)/sizeof(valids[0]); i++) {
cs_err err;
valid = valids + i;
err = cs_open(valid->arch, valid->mode, &handle);
if (err) {
printf("Failed on cs_open() with error returned: %u\n", err);
continue;
}
cs_option(handle, CS_OPT_DETAIL, CS_OPT_ON);
cs_option(handle, CS_OPT_SYNTAX, CS_OPT_SYNTAX_NOREGNAME);
#define _this_printf(...) \
{ \
size_t used = 0; \
used = snprintf(tmp_buf + cur, left, __VA_ARGS__); \
left -= used; \
cur += used; \
}
printf("\nShould be valid\n"
"---------------\n");
for (j = 0; j < valid->num_valid_codes; ++j) {
char tmp_buf[2048];
size_t left = 2048;
size_t cur = 0;
size_t used = 0;
int success = 0;
char * hex_str = NULL;
struct valid_code * valid_code = NULL;
valid_code = valid->valid_codes + j;
hex_str = hex_string(valid_code->code, valid_code->size);
printf("%s %s @ 0x%04x: %s\n %s",
valid->platform_comment, hex_str, valid_code->start_addr,
valid_code->comment, valid_code->expected_out);
count = cs_disasm(handle,
valid_code->code, valid_code->size,
valid_code->start_addr, 0, &insn
);
if (count) {
size_t k;
size_t max_len = 0;
size_t tmp_len = 0;
for (k = 0; k < count; k++) {
_this_printf(
"0x%"PRIx64":\t%s\t%s\n",
insn[k].address, insn[k].mnemonic,
insn[k].op_str
);
snprint_insn_detail(tmp_buf, &cur, &left, &insn[k]);
}
max_len = strlen(tmp_buf);
tmp_len = strlen(valid_code->expected_out);
if (tmp_len > max_len) {
max_len = tmp_len;
}
if (memcmp(tmp_buf, valid_code->expected_out, max_len)) {
printf(
" ERROR: '''\n%s''' does not match"
" expected '''\n%s'''\n",
tmp_buf, valid_code->expected_out
);
} else {
printf(" SUCCESS: valid\n");
}
cs_free(insn, count);
} else {
printf("ERROR: invalid\n");
}
}
cs_close(&handle);
}
#undef _this_prinf
}
int main()
{
test_invalids();
test_valids();
return 0;
}