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/* memory dump utility
* -scut
*/
#include <sys/types.h>
#include <sys/ptrace.h>
#include <sys/wait.h>
#include <sys/user.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <libgen.h> /* basename */
void dr_dump (FILE *out, struct user *child);
void hexdump (unsigned char *data, unsigned int amount);
int
main (int argc, char *argv[], char *envp[])
{
pid_t fpid; /* child pid, gets ptraced */
char * argv0;
struct user regs; /* PTRACE pulled registers */
unsigned long int addr, /* segment start address */
addr_end, /* segment end address */
len; /* length of segment */
unsigned long int addr_walker, /* walker to dump memory */
eip; /* current childs eip */
/* array to temporarily store data into */
unsigned char data_saved[sizeof (unsigned long int)];
/* file to read mapping information */
FILE * map_f; /* /proc/<pid>/maps stream */
unsigned char map_line[256]; /* one line each from map */
/* data for the dump files */
FILE * dump_f; /* stream */
char dump_name[64]; /* filename buffer */
if (argc < 2) {
printf ("usage: %s <argv0 [argv1 [...]]>\n\n", argv[0]);
printf ("will run 'argv0' as program with given arguments.\n\n");
exit (EXIT_FAILURE);
}
fpid = fork ();
if (fpid < 0) {
perror ("fork");
exit (EXIT_FAILURE);
}
if (fpid == 0) { /* child */
if (ptrace (PTRACE_TRACEME, 0, NULL, NULL) != 0) {
perror ("ptrace PTRACE_TRACEME");
exit (EXIT_FAILURE);
}
fprintf (stderr, " child: TRACEME set\n");
fprintf (stderr, " child: executing: %s\n", argv[2]);
close (1);
dup2 (2, 1);
execve (argv[1], &argv[1], envp);
/* failed ? */
perror ("execve");
exit (EXIT_FAILURE);
}
wait (NULL);
memset (®s, 0, sizeof (regs));
if (ptrace (PTRACE_GETREGS, fpid, NULL, ®s) < 0) {
perror ("ptrace PTRACE_GETREGS");
exit (EXIT_FAILURE);
}
fprintf (stderr, "[0x%08lx] first stop\n", regs.regs.eip);
dr_dump (stderr, ®s);
regs.u_debugreg[0] = 0x41414141;
if (ptrace (PTRACE_SETREGS, fpid, NULL, ®s) < 0) {
perror ("ptrace PTRACE_GETREGS");
exit (EXIT_FAILURE);
}
sleep (10);
if (ptrace (PTRACE_GETREGS, fpid, NULL, ®s) < 0) {
perror ("ptrace PTRACE_GETREGS");
exit (EXIT_FAILURE);
}
fprintf (stderr, "[0x%08lx] first stop\n", regs.regs.eip);
dr_dump (stderr, ®s);
/* now single step until given eip is reached */
do {
sleep (1);
if (ptrace (PTRACE_SYSCALL, fpid, NULL, NULL) < 0) {
perror ("ptrace PTRACE_SINGLESTEP");
exit (EXIT_FAILURE);
}
wait (NULL);
memset (®s, 0, sizeof (regs));
if (ptrace (PTRACE_GETREGS, fpid, NULL, ®s) < 0) {
perror ("ptrace PTRACE_GETREGS");
exit (EXIT_FAILURE);
}
fprintf (stderr, "0x%08lx\n", regs.regs.eip);
dr_dump (stderr, ®s);
} while (1);
if (ptrace (PTRACE_DETACH, fpid, NULL, NULL) < 0) {
perror ("ptrace PTRACE_DETACH");
exit (EXIT_FAILURE);
}
fprintf (stderr, "MEMDUMP: success. terminating.\n");
exit (EXIT_SUCCESS);
}
void
hexdump (unsigned char *data, unsigned int amount)
{
unsigned int dp, p; /* data pointer */
const char trans[] =
"................................ !\"#$%&'()*+,-./0123456789"
":;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklm"
"nopqrstuvwxyz{|}~...................................."
"....................................................."
"........................................";
for (dp = 1; dp <= amount; dp++) {
printf ("%02x ", data[dp-1]);
if ((dp % 8) == 0)
printf (" ");
if ((dp % 16) == 0) {
printf ("| ");
p = dp;
for (dp -= 16; dp < p; dp++)
printf ("%c", trans[data[dp]]);
printf ("\n");
}
}
if ((amount % 16) != 0) {
p = dp = 16 - (amount % 16);
for (dp = p; dp > 0; dp--) {
printf (" ");
if (((dp % 8) == 0) && (p != 8))
printf (" ");
}
printf (" | ");
for (dp = (amount - (16 - p)); dp < amount; dp++)
printf ("%c", trans[data[dp]]);
}
printf ("\n");
return;
}
void
dr_dump (FILE *out, struct user *child)
{
char * desc[] = { "dr0 (debug address register)",
"dr1 (debug address register)",
"dr2 (debug address register)",
"dr3 (debug address register)",
"dr4 (reserved)",
"dr5 (reserved)",
"dr6 (debug status register)",
"dr7 (debug control register)" };
int n;
for (n = 0 ; n < 8 ; ++n) {
fprintf (out, "\t0x%08lx %s\n", child->u_debugreg[n],
desc[n]);
}
}
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