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#include "fuzz.h"
#include "session.h"
#include "fuzz-wrapfd.h"
#include "debug.h"
#include "runopts.h"
#include "algo.h"
#include "bignum.h"
int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
static int once = 0;
static struct key_context* keep_newkeys = NULL;
/* number of generated parameters is limited by the timeout for the first run.
TODO move this to the libfuzzer initialiser function instead if the timeout
doesn't apply there */
#define NUM_PARAMS 20
static struct kex_dh_param *dh_params[NUM_PARAMS];
if (!once) {
fuzz_common_setup();
fuzz_svr_setup();
keep_newkeys = (struct key_context*)m_malloc(sizeof(struct key_context));
keep_newkeys->algo_kex = fuzz_get_algo(sshkex, "diffie-hellman-group14-sha256");
keep_newkeys->algo_hostkey = DROPBEAR_SIGNKEY_ECDSA_NISTP256;
ses.newkeys = keep_newkeys;
/* Pre-generate parameters */
int i;
for (i = 0; i < NUM_PARAMS; i++) {
dh_params[i] = gen_kexdh_param();
}
once = 1;
}
if (fuzz_set_input(Data, Size) == DROPBEAR_FAILURE) {
return 0;
}
m_malloc_set_epoch(1);
if (setjmp(fuzz.jmp) == 0) {
/* Based on recv_msg_kexdh_init()/send_msg_kexdh_reply()
with DROPBEAR_KEX_NORMAL_DH */
ses.newkeys = keep_newkeys;
/* Choose from the collection of ecdh params */
unsigned int e = buf_getint(fuzz.input);
struct kex_dh_param * dh_param = dh_params[e % NUM_PARAMS];
DEF_MP_INT(dh_e);
m_mp_init(&dh_e);
if (buf_getmpint(fuzz.input, &dh_e) != DROPBEAR_SUCCESS) {
dropbear_exit("Bad kex value");
}
ses.kexhashbuf = buf_new(KEXHASHBUF_MAX_INTS);
kexdh_comb_key(dh_param, &dh_e, svr_opts.hostkey);
mp_clear(ses.dh_K);
m_free(ses.dh_K);
mp_clear(&dh_e);
buf_free(ses.hash);
buf_free(ses.session_id);
/* kexhashbuf is freed in kexdh_comb_key */
m_malloc_free_epoch(1, 0);
} else {
m_malloc_free_epoch(1, 1);
TRACE(("dropbear_exit longjmped"))
/* dropbear_exit jumped here */
}
return 0;
}
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