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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 const struct dropbear_kex *ecdh[3]; /* 256, 384, 521 */
static struct key_context* keep_newkeys = NULL;
/* number of generated parameters is limited by the timeout for the first run */
#define NUM_PARAMS 300
static struct kex_ecdh_param *ecdh_params[NUM_PARAMS];
if (!once) {
fuzz_common_setup();
fuzz_svr_setup();
/* ses gets zeroed by fuzz_set_input */
keep_newkeys = (struct key_context*)m_malloc(sizeof(struct key_context));
ecdh[0] = fuzz_get_algo(sshkex, "ecdh-sha2-nistp256");
ecdh[1] = fuzz_get_algo(sshkex, "ecdh-sha2-nistp384");
ecdh[2] = fuzz_get_algo(sshkex, "ecdh-sha2-nistp521");
assert(ecdh[0]);
assert(ecdh[1]);
assert(ecdh[2]);
keep_newkeys->algo_hostkey = DROPBEAR_SIGNKEY_ECDSA_NISTP256;
ses.newkeys = keep_newkeys;
/* Pre-generate parameters */
int i;
for (i = 0; i < NUM_PARAMS; i++) {
ses.newkeys->algo_kex = ecdh[i % 3];
ecdh_params[i] = gen_kexecdh_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_ECDH */
ses.newkeys = keep_newkeys;
/* random choice of ecdh 256, 384, 521 */
unsigned char b = buf_getbyte(fuzz.input);
ses.newkeys->algo_kex = ecdh[b % 3];
/* Choose from the collection of ecdh params */
unsigned int e = buf_getint(fuzz.input);
struct kex_ecdh_param *ecdh_param = ecdh_params[e % NUM_PARAMS];
buffer * ecdh_qs = buf_getstringbuf(fuzz.input);
ses.kexhashbuf = buf_new(4);
buf_putint(ses.kexhashbuf, 12345);
kexecdh_comb_key(ecdh_param, ecdh_qs, svr_opts.hostkey);
/* kexhashbuf is freed in kexdh_comb_key */
m_free(ses.dh_K);
buf_free(ecdh_qs);
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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