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#include "includes.h"
#include "includes.h"
#include "fuzz.h"
#include "dbutil.h"
#include "runopts.h"
#include "crypto_desc.h"
#include "session.h"
#include "dbrandom.h"
#include "fuzz-wrapfd.h"
struct dropbear_fuzz_options fuzz;
static void load_fixed_hostkeys(void);
static void common_setup_fuzzer(void) {
fuzz.fuzzing = 1;
fuzz.wrapfds = 1;
fuzz.input = m_malloc(sizeof(buffer));
crypto_init();
}
int fuzzer_set_input(const uint8_t *Data, size_t Size) {
fuzz.input->data = (unsigned char*)Data;
fuzz.input->size = Size;
fuzz.input->len = Size;
fuzz.input->pos = 0;
// get prefix. input format is
// string prefix
// uint32 wrapfd seed
// ... to be extended later
// [bytes] ssh input stream
// be careful to avoid triggering buffer.c assertions
if (fuzz.input->len < 8) {
return DROPBEAR_FAILURE;
}
size_t prefix_size = buf_getint(fuzz.input);
if (prefix_size != 4) {
return DROPBEAR_FAILURE;
}
uint32_t wrapseed = buf_getint(fuzz.input);
wrapfd_setup(wrapseed);
seedrandom();
return DROPBEAR_SUCCESS;
}
void svr_setup_fuzzer(void) {
struct passwd *pw;
common_setup_fuzzer();
_dropbear_exit = svr_dropbear_exit;
_dropbear_log = svr_dropbear_log;
char *argv[] = {
"-E",
};
int argc = sizeof(argv) / sizeof(*argv);
svr_getopts(argc, argv);
/* user lookups might be slow, cache it */
pw = getpwuid(getuid());
dropbear_assert(pw);
fuzz.pw_name = m_strdup(pw->pw_name);
fuzz.pw_dir = m_strdup(pw->pw_dir);
fuzz.pw_shell = m_strdup(pw->pw_shell);
fuzz.pw_passwd = m_strdup("!!zzznope");
load_fixed_hostkeys();
}
static void load_fixed_hostkeys(void) {
#include "fuzz-hostkeys.c"
buffer *b = buf_new(3000);
enum signkey_type type;
TRACE(("load fixed hostkeys"))
svr_opts.hostkey = new_sign_key();
buf_setlen(b, 0);
buf_putbytes(b, keyr, keyr_len);
buf_setpos(b, 0);
type = DROPBEAR_SIGNKEY_RSA;
if (buf_get_priv_key(b, svr_opts.hostkey, &type) == DROPBEAR_FAILURE) {
dropbear_exit("failed fixed rsa hostkey");
}
buf_setlen(b, 0);
buf_putbytes(b, keyd, keyd_len);
buf_setpos(b, 0);
type = DROPBEAR_SIGNKEY_DSS;
if (buf_get_priv_key(b, svr_opts.hostkey, &type) == DROPBEAR_FAILURE) {
dropbear_exit("failed fixed dss hostkey");
}
buf_setlen(b, 0);
buf_putbytes(b, keye, keye_len);
buf_setpos(b, 0);
type = DROPBEAR_SIGNKEY_ECDSA_NISTP256;
if (buf_get_priv_key(b, svr_opts.hostkey, &type) == DROPBEAR_FAILURE) {
dropbear_exit("failed fixed ecdsa hostkey");
}
buf_free(b);
}
void fuzz_kex_fakealgos(void) {
ses.newkeys->recv.crypt_mode = &dropbear_mode_none;
}
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