radare2/libr/bp/parser.c
pancake 91ad40d663 * Major unfinished refactoring for r_debug and r_bp
- radare2 debugger is now broken
  - r_reg has grown a bit more
  - Better separation of debugger elements
* r_bp now has r_bp_add_hw and r_bp_add_sw() calls
  - Added minimal support for breakpoint handlers
  - Import th0rpe's watchpoint expression parser engine
* iob moved from r_debug to r_bp
* Arch types has been moved into r_asm
  - Soft compile time dependency
* Update pkg-config .pc files
2009-09-14 00:37:28 +02:00

695 lines
12 KiB
C

/* Copyright (C) 2007, 2008, 2009 - th0rpe <nopcode.org> */
#include "parser.h"
#if 0
extern struct regs_off roff[];
extern unsigned long get_reg(char *reg);
struct regs_off roff[] = {
{"eax", R_EAX_OFF},
{"ebx", R_EBX_OFF},
{"ecx", R_ECX_OFF},
{"edx", R_EDX_OFF},
{"esi", R_ESI_OFF},
{"edi", R_EDI_OFF},
{"esp", R_ESP_OFF},
{"ebp", R_EBP_OFF},
{"eip", R_EIP_OFF},
{"eflags", R_EFLAGS_OFF},
#if __WINDOWS__
{"dr0", R_DR0_OFF},
{"dr1", R_DR1_OFF},
{"dr2", R_DR2_OFF},
{"dr3", R_DR3_OFF},
{"dr6", R_DR6_OFF},
{"dr7", R_DR7_OFF},
#endif
{0, 0}
};
#endif
#define ishexa(c) ((c >='0' && c <= '9') || \
(tolower(c) >='a' && tolower(c) <= 'f'))
/* skip \s\t and space characters */
char skip_chars(const char **c)
{
for(;**c == ' ' || **c == '\t'; *c = *c + 1)
;
return **c;
}
int get_tok_op(const char **c, struct tok *t)
{
t->op = -1;
if(**c == '>') {
if(*(*c + 1) != '=') {
t->op = _OP_GT;
*c = *c + 1;
} else {
t->op = _OP_GE;
*c = *c + 2;
}
} else if(**c == '=') {
t->op = _OP_EQ;
*c = *c + 1;
} else if(**c == '<') {
if(*(*c + 1) == '=') {
t->op = _OP_LE;
*c = *c + 1;
} else if(*(*c + 1) == '>'){
t->op = _OP_NE;
*c = *c + 2;
} else {
t->op = _OP_LT;
*c = *c + 2;
}
}
if(t->type == MEM_TOK && t->op != _OP_EQ && t->op != _OP_NE)
return -1;
return t->op;
}
int get_tok_value(const char **c, struct tok *t)
{
char aux[512];
char *val = *c;
int len;
t->val = 0;
/* hexadecimal value */
if(**c == '0' && *(*c + 1) == 'x') {
for(*c = *c + 2; ishexa(**c); *c = *c + 1) ;
len = *c - val - 2;
if( len <= 0 || (t->type == REG_TOK &&
(len >> 1) > sizeof(unsigned long)) ||
len + 2 >= sizeof(aux)) {
eprintf(":error token value too large,"
" near %s\n", val);
return -1;
}
/* copy hexadecimal string */
memcpy(aux, val, len + 2);
aux[len + 2] = 0;
if(t->type == REG_TOK) {
t->val = malloc(sizeof(unsigned long));
if(!t->val) {
perror(":error malloc tok value");
return -1;
}
*((unsigned long *)t->val) = get_math(aux);
t->len = sizeof(unsigned long);
} else {
t-> val = malloc(len);
if(!t->val) {
perror(":error malloc tok value");
return -1;
}
t->len = hexstr2binstr((const char *)aux + 2,
(unsigned char *)(aux + 2));
memcpy(t->val, aux + 2, t->len);
/*
for(i = 0; i < t->len; i++) {
printf("\\x%.2x\n", (unsigned char)t->val[i]);
}
*/
}
/* decimal value */
} else if(**c >= '0' && **c <= '9') {
for(*c = *c + 1; **c >= '0' && **c <= '9'; *c = *c + 1)
;
len = *c - val;
/* copy decimal string */
memcpy(aux, val, len);
aux[len] = 0;
t->val = malloc(sizeof(unsigned long));
if(!t->val) {
eprintf(":error malloc tok value");
return -1;
}
*((unsigned long *)t->val) = get_math(aux);
t->len = sizeof(unsigned long);
} else {
/* TODO: get value from an external script */
return -1;
}
return 0;
}
struct tok* get_tok(const char **c)
{
struct tok *t = NULL;
char aux[60];
const char *val;
int ret;
skip_chars((const char**)c);
/* register */
if(**c == '%') {
ret = get_reg(*c + 1);
if(ret < 0) {
eprintf(":error invalid register near ' %s '\n",
*c);
return NULL;
}
*c = *c + strlen(roff[ret].reg) + 1;
t = (struct tok *)malloc(sizeof(*t));
if(!t) {
perror(":error malloc parse register");
return NULL;
}
t->off = roff[ret].off;
skip_chars((const char**)c);
/* get operation */
if(get_tok_op(c, t) == -1) {
eprintf(":missing or invalid operation "
"on register ' r%s '"
"\n", roff[ret].reg);
goto err_get_tok;
}
skip_chars((const char**)c);
t->type = REG_TOK;
/* get value */
if(get_tok_value(c, t) == -1) {
eprintf(":missing or invalid value "
"on register ' r%s '"
"\n", roff[ret].reg);
goto err_get_tok;
}
/* memory */
} if(**c == '[') {
*c = *c + 1;
skip_chars((const char **)c);
val = *c;
/* hexadecimal address */
if(*val != '0' || *(val + 1) != 'x') {
eprintf(":error invalid address near ' %s '\n",
val);
return NULL;
}
*c = *c + 2;
for(; ishexa(**c) ; *c = *c + 1)
;
ret = *c - val - 2;
if((ret >> 1) > sizeof(unsigned long)) {
eprintf(":error invalid address near ' %s '\n",
val);
return NULL;
}
skip_chars((const char **)c);
if(**c != ']') {
eprintf(":error invalid sintax near ' %s '\n",
*c);
return NULL;
}
memcpy(aux, val, ret + 2);
aux[ret + 2] = 0;
t = (struct tok *)malloc(sizeof(*t));
if(!t) {
perror(":error malloc parse memory");
return NULL;
}
*c = *c + 1;
skip_chars((const char**)c);
/* get operation */
if(get_tok_op(c, t) == -1) {
eprintf(":missing or invalid operation "
"near ' %s '\n"
, *c);
goto err_get_tok;
}
skip_chars((const char**)c);
t->off = get_math(aux);
t->type = MEM_TOK;
/* get value */
if(get_tok_value(c, t) == -1) {
fprintf(stderr, ":missing or invalid value "
"near ' %s '\n"
, *c);
goto err_get_tok;
}
}
return t;
err_get_tok:
if(t)
free(t);
return NULL;
}
int get_log_op(const char **c, struct tok *t, int f)
{
if(strncmp(*c, "and", 3) == 0) {
if(!f)
return -1;
t->log_op = LOG_AND;
*c = *c + 3;
} else if(strncmp(*c, "or", 2) == 0) {
if(!f)
return -1;
t->log_op = LOG_OR;
*c = *c + 2;
}
return 0;
}
void free_cond(struct tok *group)
{
struct list_head *pos, *aux, *group_list;
struct tok *t;
assert(group->type == GROUP_TOK);
group_list = &group->list;
pos = group_list->next;
while(pos && pos != group_list)
{
t = (struct tok *)((char *)pos + \
sizeof(struct list_head) - \
sizeof(struct tok));
aux = pos->next;
if(t->type == GROUP_TOK)
free_cond(t);
list_del(&(t->next));
if(t->val)
free(t->val);
free(t);
pos = aux;
}
free(group);
}
/* TODO: free list when error */
struct tok* process_cond(const char **c, int top)
{
struct tok *t = NULL;
struct tok *group;
char *val;
int f = 0;
val = *c;
/*printf("enter condition: %s\n", val); */
group = (struct tok *)malloc(sizeof(*group));
if(!group) {
perror(":error malloc group token");
return NULL;
}
/* initialize list group */
INIT_LIST_HEAD(&group->list);
group->type = GROUP_TOK;
group->log_op = 0;
for(;**c;) {
skip_chars((const char **)c);
if(get_log_op(c, t, f) < 0) {
eprintf(":error missing token or "
" operator not valid near ' %s '\n", val);
goto err_cond;
}
skip_chars((const char **)c);
/* enter condition */
if(**c == '(') {
*c = *c + 1;
t = process_cond(c, 0);
if(!t)
goto err_cond;
list_add(&t->next, &group->list);
if(**c != ')') {
fprintf(stderr, ":error not closed condition "
" near ' %s '\n",
val);
goto err_cond;
}
*c = *c + 1;
f = 1;
/* exit condition */
} else if(**c == ')') {
if(top != 0) {
fprintf(stderr, ":error not opened "
"condition near ' %s '\n",
val);
goto err_cond;
}
break;
/* get token */
} else {
t = get_tok(c);
if(!t)
goto err_cond;
t->log_op = 0;
/* add token at group list */
list_add(&t->next, &group->list);
f = 2;
}
}
/* printf("exit condition group\n"); */
return group;
err_cond:
free_cond(group);
return NULL;
}
int eval_token_reg(struct tok *t)
{
unsigned long reg_val;
unsigned long val;
int op, ret;
if (!config.debug)
return 0;
op = t->op;
reg_val = debug_get_regoff(&WS(regs), t->off);
val = *(unsigned long *)(t->val);
switch(op) {
case _OP_LE:
ret = (reg_val <= val);
break;
case _OP_LT:
ret = (reg_val < val);
break;
case _OP_EQ:
ret = (reg_val == val);
break;
case _OP_NE:
ret = (reg_val != val);
break;
case _OP_GE:
ret = (reg_val >= val);
break;
case _OP_GT:
default:
ret = (reg_val >= val);
break;
}
return ret;
}
int eval_token_mem(struct tok *t)
{
unsigned char rvalue[512];
int op = t->op;
int ret;
if (!config.debug)
return 0;
/* printf("read_at: 0x%x %d\n", t->off, t->len); */
if(debug_read_at(ps.tid, rvalue, t->len, t->off) <= 0)
return 0;
/*
printf("val: %x %x %x %x %x %x\n", rvalue[0], rvalue[1], rvalue[2],
t->val[0], t->val[1], t->val[2]);
printf("memcmp: %x\n", memcmp(t->val, rvalue, t->len));
*/
switch(op) {
case _OP_EQ:
ret = (memcmp(t->val, rvalue, t->len) == 0);
break;
case _OP_NE:
default:
ret = (memcmp(t->val, rvalue, t->len) != 0);
}
return ret;
}
int eval_token(struct tok *t)
{
int type = t->type;
int ret;
switch(type) {
/* token register */
case REG_TOK:
ret = eval_token_reg(t);
break;
/* token memory */
case MEM_TOK:
default:
ret = eval_token_mem(t);
break;
}
return ret;
}
int eval_cond(struct tok *group)
{
struct list_head *pos;
int log_op = 0, val_cond = 1;
assert(group->type == GROUP_TOK);
/* printf("EVAL enter group\n"); */
list_for_each_prev(pos, &group->list) {
struct tok *t = (struct tok *)((char *)pos + \
sizeof(struct list_head) - \
sizeof(struct tok));
/* not evalue next 'or' conditions
when the condition is true yet or
the condition is false and exist next 'and'
conditions
*/
if( (val_cond && log_op == LOG_OR) ||
(!val_cond && log_op == LOG_AND))
continue;
if(t->log_op)
log_op = t->log_op;
switch(t->type) {
case GROUP_TOK:
val_cond = eval_cond(t);
break;
default:
val_cond = eval_token(t);
}
}
/* printf("EVAL exit group\n"); */
return val_cond;
}
void print_token(struct tok *t)
{
char *op;
char *log_op;
switch(t->op) {
case _OP_LE:
op = "<=";
break;
case _OP_LT:
op = "<";
break;
case _OP_EQ:
op = "=";
break;
case _OP_NE:
op = "<>";
break;
case _OP_GE:
op = ">=";
break;
case _OP_GT:
op = ">";
break;
default:
op = "none";
}
if(t->log_op == LOG_OR)
log_op = "or";
else if(t->log_op == LOG_AND)
log_op = "and";
else
log_op = "";
if(t->type == REG_TOK) {
printf( "register off %i\n"
"logical op %s\n"
"operator %s\n"
"value %x\n"
,(unsigned int)t->off
,log_op
,op
,(unsigned int)*((unsigned long *)t->val)
);
} else if(t->type == MEM_TOK) {
printf( "memory %x\n"
"logical op %s\n"
"operator %s\n"
"val %x\n"
"len %d\n"
,(unsigned int)t->off
,log_op
,op
,(unsigned int)*((unsigned long *)t->val)
,(unsigned int)t->len
);
} else {
printf(" operator group %s\n", log_op);
}
}
void print_expr(struct tok *group)
{
struct list_head *pos;
assert(group->type == GROUP_TOK);
printf("enter group\n");
list_for_each_prev(pos, &group->list) {
struct tok *t = (struct tok *)((char *)pos + \
sizeof(struct list_head) - \
sizeof(struct tok));
switch(t->type) {
case GROUP_TOK:
print_token(t);
print_expr(t);
break;
default:
print_token(t);
}
}
printf("exit group\n");
}
struct tok* parse_cond(const char *cond)
{
return process_cond(&cond, 1);
}
#if 0
void test_parser()
{
struct tok *gr;
char *v;
char *p = "reip >= 0x01020304 and rebx = 15 "
"and ([0x80456] = 10 or reip = 5) "
"and ([0xff456] = 1 and reip = 2) or "
"(reax <> 10 and recx = 4)"
;
v = p;
gr = process_cond(&p, 1);
if(gr) {
print_expr(gr);
printf("cond: %s\n", v);
printf("eval cond: %d\n", eval_cond(gr));
}
}
#endif