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/*
Declaration for Linux kernel compatibility
*/
#include <assert.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/ptrace.h>
#include "extra.h"
pid_t victim_pid= -1;
char *victim_exe= NULL;
#define TRAP_BIT (0x80000000)
static struct nlist *exe_nlist;
static int exe_nlist_n;
void printk(char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
}
int kallsyms_address_to_symbol(db_expr_t off,
const char * *mod_name, unsigned long *mod_start, unsigned long *mod_end,
const char * *sec_name, unsigned long *sec_start, unsigned long *sec_end,
const char * *sym_name, unsigned long *sym_start, unsigned long *sym_end)
{
static char name[64];
int i;
unsigned long btext, etext;
struct nlist *below, *above;
off &= ~TRAP_BIT;
load_nlist(victim_exe, &btext, &etext);
below= above= NULL;
for (i= 0; i<exe_nlist_n; i++)
{
if (exe_nlist[i].n_type != N_TEXT)
continue;
if (exe_nlist[i].n_value <= off)
{
if (!below || exe_nlist[i].n_value > below->n_value)
below= &exe_nlist[i];
}
if (exe_nlist[i].n_value > off)
{
if (!above || exe_nlist[i].n_value < above->n_value)
above= &exe_nlist[i];
}
}
btext |= TRAP_BIT;
etext |= TRAP_BIT;
*mod_name = victim_exe;
*mod_start = btext;
*mod_end = etext;
*sec_name = ".text";
*sec_start = btext;
*sec_end = etext;
assert(below && above);
strncpy(name, below->n_name, sizeof(name)-1);
name[sizeof(name)-1]= '\0';
*sym_name= name;
*sym_start= below->n_value | TRAP_BIT;
*sym_end= above->n_value | TRAP_BIT;
return 1;
}
unsigned long text_read_ul(void *addr)
{
int i;
unsigned long value;
for (i= 0; i<sizeof(value); i++)
{
((unsigned char *)&value)[i]= text_read_ub((char *)addr+i);
}
return value;
}
unsigned char text_read_ub(void *addr)
{
int v;
unsigned long vaddr;
vaddr= (unsigned long)addr;
vaddr &= ~TRAP_BIT;
v= ptrace(T_READB_INS, victim_pid, (void *)vaddr, 0);
if (v < 0)
{
fprintf(stderr,
"text_read_ub: trace T_READB_INS failed on pid %d, addr 0x%lx: %s\n",
victim_pid, vaddr, strerror(errno));
exit(1);
}
return v;
}
void text_write_ul(void *addr, unsigned long value)
{
int i;
for (i= 0; i<sizeof(value); i++)
{
text_write_ub((char *)addr+i, ((unsigned char *)&value)[i]);
}
}
void text_write_ub(void *addr, unsigned char value)
{
int v;
unsigned long vaddr;
vaddr= (unsigned long)addr;
vaddr &= ~TRAP_BIT;
v= ptrace(T_WRITEB_INS, victim_pid, (void *)vaddr, value);
if (v < 0)
{
fprintf(stderr,
"text_read_ub: trace T_WRITEB_INS failed on pid %d, addr 0x%lx: %s\n",
victim_pid, vaddr, strerror(errno));
exit(1);
}
}
void load_nlist(exe_name, btextp, etextp)
char *exe_name;
unsigned long *btextp;
unsigned long *etextp;
{
int i;
unsigned long btext, etext;
if (!exe_nlist)
{
exe_nlist_n= read_nlist(exe_name, &exe_nlist);
if (exe_nlist_n <= 0)
{
if (exe_nlist_n == -1)
{
fprintf(stderr,
"error reading name list from '%s': %s\n",
exe_name, strerror(errno));
}
else
fprintf(stderr, "no name list in '%s'\n",
exe_name);
exit(1);
}
}
if (!btextp && !etextp)
return;
etext= 0;
btext= (unsigned long)-1;
for (i= 0; i<exe_nlist_n; i++)
{
if (exe_nlist[i].n_type != N_TEXT)
continue;
if (exe_nlist[i].n_value < btext)
btext= exe_nlist[i].n_value;
if (exe_nlist[i].n_value > etext)
etext= exe_nlist[i].n_value;
}
if (btext >= etext)
{
fprintf(stderr, "Bad btext (0x%lx) or etext (0x%lx) in %s\n",
btext, etext, exe_name);
exit(1);
}
btext |= TRAP_BIT;
etext |= TRAP_BIT;
if (btextp)
*btextp= btext;
if (etextp)
*etextp= etext;
}
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