radare2/libr/main/ragg2.c
phakeobj 3f0cfff3d5
Fix incorrect ragg2 empty string check (#17202)
* Check for empty path string only if |file| actually exists
* Add a test that would have spot this bug in first place
2020-07-03 21:09:42 +02:00

626 lines
14 KiB
C

/* radare - LGPL - Copyright 2011-2020 - pancake */
#include <r_egg.h>
#include <r_bin.h>
#include <r_main.h>
#include <r_util/r_print.h>
#include <r_util.h>
static int usage(int v) {
printf ("Usage: ragg2 [-FOLsrxhvz] [-a arch] [-b bits] [-k os] [-o file] [-I path]\n"
" [-i sc] [-e enc] [-B hex] [-c k=v] [-C file] [-p pad] [-q off]\n"
" [-S string] [-f fmt] [-nN dword] [-dDw off:hex] file|f.asm|-\n");
if (v) {
printf (
" -a [arch] select architecture (x86, mips, arm)\n"
" -b [bits] register size (32, 64, ..)\n"
" -B [hexpairs] append some hexpair bytes\n"
" -c [k=v] set configuration options\n"
" -C [file] append contents of file\n"
" -d [off:dword] patch dword (4 bytes) at given offset\n"
" -D [off:qword] patch qword (8 bytes) at given offset\n"
" -e [encoder] use specific encoder. see -L\n"
" -f [format] output format (raw, c, pe, elf, mach0, python, javascript)\n"
" -F output native format (osx=mach0, linux=elf, ..)\n"
" -h show this help\n"
" -i [shellcode] include shellcode plugin, uses options. see -L\n"
" -I [path] add include path\n"
" -k [os] operating system's kernel (linux,bsd,osx,w32)\n"
" -L list all plugins (shellcodes and encoders)\n"
" -n [dword] append 32bit number (4 bytes)\n"
" -N [dword] append 64bit number (8 bytes)\n"
" -o [file] output file\n"
" -O use default output file (filename without extension or a.out)\n"
" -p [padding] add padding after compilation (padding=n10s32)\n"
" ntas : begin nop, trap, 'a', sequence\n"
" NTAS : same as above, but at the end\n"
" -P [size] prepend debruijn pattern\n"
" -q [fragment] debruijn pattern offset\n"
" -r show raw bytes instead of hexpairs\n"
" -s show assembler\n"
" -S [string] append a string\n"
" -v show version\n"
" -w [off:hex] patch hexpairs at given offset\n"
" -x execute\n"
" -X [hexpairs] execute rop chain, using the stack provided\n"
" -z output in C string syntax\n");
}
return 1;
}
static void list(REgg *egg) {
RListIter *iter;
REggPlugin *p;
printf ("shellcodes:\n");
r_list_foreach (egg->plugins, iter, p) {
if (p->type == R_EGG_PLUGIN_SHELLCODE) {
printf ("%10s : %s\n", p->name, p->desc);
}
}
printf ("encoders:\n");
r_list_foreach (egg->plugins, iter, p) {
if (p->type == R_EGG_PLUGIN_ENCODER) {
printf ("%10s : %s\n", p->name, p->desc);
}
}
}
static int create(const char *format, const char *arch, int bits, const ut8 *code, int codelen) {
RBin *bin = r_bin_new ();
RBinArchOptions opts;
RBuffer *b;
r_bin_arch_options_init (&opts, arch, bits);
b = r_bin_create (bin, format, code, codelen, NULL, 0, &opts);
if (b) {
ut64 blen;
const ut8 *tmp = r_buf_data (b, &blen);
if (write (1, tmp, blen) != blen) {
eprintf ("Failed to write buffer\n");
}
r_buf_free (b);
} else {
eprintf ("Cannot create binary for this format '%s'.\n", format);
}
r_bin_free (bin);
return 0;
}
static int openfile(const char *f, int x) {
int fd = open (f, O_RDWR | O_CREAT, 0644);
if (fd == -1) {
fd = open (f, O_RDWR);
if (fd == -1) {
return -1;
}
}
#if __UNIX__
if (x) {
fchmod (fd, 0755);
}
#endif
#if _MSC_VER
int r = _chsize (fd, 0);
#else
int r = ftruncate (fd, 0);
#endif
if (r != 0) {
eprintf ("Could not resize\n");
}
close (1);
dup2 (fd, 1);
return fd;
}
#define ISEXEC (fmt!='r')
R_API int r_main_ragg2(int argc, const char **argv) {
const char *file = NULL;
const char *padding = NULL;
const char *pattern = NULL;
const char *str = NULL;
char *bytes = NULL;
const char *contents = NULL;
const char *arch = R_SYS_ARCH;
const char *os = R_EGG_OS_NAME;
const char *format = "raw";
bool show_execute = false;
bool show_execute_rop = false;
int show_hex = 1;
int show_asm = 0;
int show_raw = 0;
int append = 0;
int show_str = 0;
ut64 get_offset = 0;
const char *shellcode = NULL;
const char *encoder = NULL;
char *sequence = NULL;
int bits = (R_SYS_BITS & R_SYS_BITS_64)? 64: 32;
int fmt = 0;
const char *ofile = NULL;
int ofileauto = 0;
RBuffer *b;
int c, i, fd = -1;
REgg *egg = r_egg_new ();
RGetopt opt;
r_getopt_init (&opt, argc, argv, "n:N:he:a:b:f:o:sxXrk:FOI:Li:c:p:P:B:C:vd:D:w:zq:S:");
while ((c = r_getopt_next (&opt)) != -1) {
switch (c) {
case 'a':
arch = opt.arg;
if (!strcmp (arch, "trace")) {
show_asm = 1;
show_hex = 0;
}
break;
case 'e':
encoder = opt.arg;
break;
case 'b':
bits = atoi (opt.arg);
break;
case 'B':
bytes = r_str_append (bytes, opt.arg);
break;
case 'C':
if (R_STR_ISEMPTY (opt.arg)) {
eprintf ("Cannot open empty contents path\n");
free (sequence);
r_egg_free (egg);
return 1;
}
contents = opt.arg;
break;
case 'w':
{
char *arg = strdup (opt.arg);
char *p = strchr (arg, ':');
if (p) {
int len, off;
ut8 *b;
*p++ = 0;
off = r_num_math (NULL, arg);
b = malloc (strlen (opt.arg) + 1);
len = r_hex_str2bin (p, b);
if (len > 0) {
r_egg_patch (egg, off, (const ut8*)b, len);
} else {
eprintf ("Invalid hexstr for -w\n");
}
free (b);
} else {
eprintf ("Missing colon in -w\n");
}
free (arg);
}
break;
case 'n':
{
ut32 n = r_num_math (NULL, opt.arg);
append = 1;
r_egg_patch (egg, -1, (const ut8*)&n, 4);
}
break;
case 'N':
{
ut64 n = r_num_math (NULL, opt.arg);
r_egg_patch (egg, -1, (const ut8*)&n, 8);
append = 1;
}
break;
case 'd':
{
ut32 off, n;
char *p = strchr (opt.arg, ':');
if (p) {
*p = 0;
off = r_num_math (NULL, opt.arg);
n = r_num_math (NULL, p + 1);
*p = ':';
// TODO: honor endianness here
r_egg_patch (egg, off, (const ut8*)&n, 4);
} else {
eprintf ("Missing colon in -d\n");
}
}
break;
case 'D':
{
char *p = strchr (opt.arg, ':');
if (p) {
ut64 n, off = r_num_math (NULL, opt.arg);
n = r_num_math (NULL, p + 1);
// TODO: honor endianness here
r_egg_patch (egg, off, (const ut8*)&n, 8);
} else {
eprintf ("Missing colon in -d\n");
}
}
break;
case 'S':
str = opt.arg;
break;
case 'o':
ofile = opt.arg;
break;
case 'O':
ofileauto = 1;
break;
case 'I':
if (R_STR_ISEMPTY (opt.arg)) {
eprintf ("Cannot open empty include path\n");
free (sequence);
r_egg_free (egg);
return 1;
}
r_egg_lang_include_path (egg, opt.arg);
break;
case 'i':
shellcode = opt.arg;
break;
case 'p':
padding = opt.arg;
break;
case 'P':
pattern = opt.arg;
break;
case 'c':
{
char *p = strchr (opt.arg, '=');
if (p) {
*p++ = 0;
r_egg_option_set (egg, opt.arg, p);
} else {
r_egg_option_set (egg, opt.arg, "true");
}
}
break;
case 'F':
#if __APPLE__
format = "mach0";
#elif __WINDOWS__
format = "pe";
#else
format = "elf";
#endif
show_asm = 0;
break;
case 'f':
format = opt.arg;
show_asm = 0;
break;
case 's':
show_asm = 1;
show_hex = 0;
break;
case 'k':
os = opt.arg;
break;
case 'r':
show_raw = 1;
break;
case 'x':
// execute
show_execute = true;
break;
case 'X':
// execute rop chain
show_execute = 1;
show_execute_rop = 1;
break;
case 'L':
list (egg);
r_egg_free (egg);
free (sequence);
return 0;
case 'h':
r_egg_free (egg);
free (sequence);
return usage (1);
case 'v':
free (sequence);
r_egg_free (egg);
return r_main_version_print ("ragg2");
case 'z':
show_str = 1;
break;
case 'q':
get_offset = 1;
sequence = strdup (opt.arg);
break;
default:
free (sequence);
r_egg_free (egg);
return 1;
}
}
if (opt.ind == argc && !shellcode && !bytes && !contents && !encoder && !padding && !pattern && !append && !get_offset && !str) {
free (sequence);
r_egg_free (egg);
return usage (0);
} else {
file = argv[opt.ind];
}
if (bits == 64) {
if (!strcmp (format, "mach0")) {
format = "mach064";
} else if (!strcmp (format, "elf")) {
format = "elf64";
}
}
// catch this first
if (get_offset) {
if (strncmp (sequence, "0x", 2)) {
eprintf ("Need hex value with `0x' prefix e.g. 0x41414142\n");
free (sequence);
r_egg_free (egg);
return 1;
}
get_offset = r_num_math (0, sequence);
printf ("Little endian: %d\n", r_debruijn_offset (get_offset, false));
printf ("Big endian: %d\n", r_debruijn_offset (get_offset, true));
free (sequence);
r_egg_free (egg);
return 0;
}
// initialize egg
r_egg_setup (egg, arch, bits, 0, os);
if (file) {
if (R_STR_ISEMPTY (file)) {
eprintf ("Cannot open empty path\n");
goto fail;
}
if (!strcmp (file, "-")) {
char buf[1024];
for (;;) {
if (!fgets (buf, sizeof (buf), stdin)) {
break;
}
if (feof (stdin)) {
break;
}
r_egg_load (egg, buf, 0);
}
} else if (strstr (file, ".c")) {
char *fileSanitized = strdup (file);
r_str_sanitize (fileSanitized);
char *textFile = r_egg_Cfile_parser (fileSanitized, arch, os, bits);
if (!textFile) {
eprintf ("Failure while parsing '%s'\n", fileSanitized);
goto fail;
}
size_t l;
char *buf = r_file_slurp (textFile, &l);
if (buf && l > 0) {
r_egg_raw (egg, (const ut8*)buf, (int)l);
} else {
eprintf ("Error loading '%s'\n", textFile);
}
r_file_rm (textFile);
free (fileSanitized);
free (textFile);
free (buf);
} else {
if (strstr (file, ".s") || strstr (file, ".asm")) {
fmt = 'a';
} else {
fmt = 0;
}
if (!r_egg_include (egg, file, fmt)) {
eprintf ("Cannot open '%s'\n", file);
goto fail;
}
}
}
// compile source code to assembly
if (!r_egg_compile (egg)) {
if (!fmt) {
eprintf ("r_egg_compile: fail\n");
free (sequence);
r_egg_free (egg);
return 1;
}
}
// append the provided string
if (str) {
int l = strlen (str);
if (l > 0) {
r_egg_raw (egg, (const ut8*)str, l);
}
}
// add raw file
if (contents) {
size_t l;
char *buf = r_file_slurp (contents, &l);
if (buf && l > 0) {
r_egg_raw (egg, (const ut8*)buf, (int)l);
} else {
eprintf ("Error loading '%s'\n", contents);
}
free (buf);
}
// add shellcode
if (shellcode) {
if (!r_egg_shellcode (egg, shellcode)) {
eprintf ("Unknown shellcode '%s'\n", shellcode);
goto fail;
}
}
// add raw bytes
if (bytes) {
ut8 *b = malloc (strlen (bytes) + 1);
int len = r_hex_str2bin (bytes, b);
if (len > 0) {
if (!r_egg_raw (egg, b, len)) {
eprintf ("Unknown '%s'\n", shellcode);
free (b);
goto fail;
}
} else {
eprintf ("Invalid hexpair string for -B\n");
}
free (b);
free (bytes);
bytes = NULL;
}
/* set output (create output file if needed) */
if (ofileauto) {
if (file) {
char *o, *q, *p = strdup (file);
if ((o = strchr (p, '.'))) {
while ( (q = strchr (o + 1, '.')) ) {
o = q;
}
*o = 0;
fd = openfile (p, ISEXEC);
} else {
fd = openfile ("a.out", ISEXEC);
}
free (p);
} else {
fd = openfile ("a.out", ISEXEC);
}
if (fd == -1) {
eprintf ("cannot open file '%s'\n", opt.arg);
goto fail;
}
close (fd);
}
if (ofile) {
fd = openfile (ofile, ISEXEC);
if (fd == -1) {
eprintf ("cannot open file '%s'\n", ofile);
goto fail;
}
}
// assemble to binary
if (!r_egg_assemble (egg)) {
eprintf ("r_egg_assemble: invalid assembly\n");
goto fail;
}
if (encoder) {
if (!r_egg_encode (egg, encoder)) {
eprintf ("Invalid encoder '%s'\n", encoder);
goto fail;
}
}
// add padding
if (padding) {
r_egg_padding (egg, padding);
}
// add pattern
if (pattern) {
r_egg_pattern (egg, r_num_math (NULL, pattern));
}
// apply patches
if (!egg->bin) {
egg->bin = r_buf_new ();
}
if (!(b = r_egg_get_bin (egg))) {
eprintf ("r_egg_get_bin: invalid egg :(\n");
goto fail;
}
r_egg_finalize (egg);
if (show_asm) {
printf ("%s\n", r_egg_get_assembly (egg));
}
if (show_raw || show_hex || show_execute) {
if (show_execute) {
int r;
if (show_execute_rop) {
r = r_egg_run_rop (egg);
} else {
r = r_egg_run (egg);
}
r_egg_free (egg);
return r;
}
b = r_egg_get_bin (egg);
if (show_raw) {
ut64 blen;
const ut8 *tmp = r_buf_data (b, &blen);
if (write (1, tmp, blen) != blen) {
eprintf ("Failed to write buffer\n");
goto fail;
}
} else {
if (!format) {
eprintf ("No format specified wtf\n");
goto fail;
}
RPrint *p = r_print_new ();
ut64 tmpsz;
const ut8 *tmp = r_buf_data (b, &tmpsz);
switch (*format) {
case 'c':
r_print_code (p, 0, tmp, tmpsz, 'c');
break;
case 'j': // JavaScript
r_print_code (p, 0, tmp, tmpsz, 'j');
break;
case 'r':
if (show_str) {
printf ("\"");
for (i = 0; i < tmpsz; i++) {
printf ("\\x%02x", tmp[i]);
}
printf ("\"\n");
} else if (show_hex) {
r_buf_seek (b, 0, R_BUF_SET);
for (i = 0; i < tmpsz; i++) {
printf ("%02x", tmp[i]);
}
printf ("\n");
} // else show_raw is_above()
break;
case 'p': // PE
if (strlen(format) >= 2 && format[1] == 'y') { // Python
r_print_code (p, 0, tmp, tmpsz, 'p');
}
break;
case 'e': // ELF
case 'm': // MACH0
create (format, arch, bits, tmp, tmpsz);
break;
default:
eprintf ("unknown executable format (%s)\n", format);
goto fail;
}
r_print_free (p);
}
}
if (fd != -1) {
close (fd);
}
free (sequence);
r_egg_free (egg);
return 0;
fail:
if (fd != -1) {
close (fd);
}
free (sequence);
r_egg_free (egg);
return 1;
}