Mercurial > dropbear
view fuzzer-kexdh.c @ 1629:258b57b208ae
Fix for issue successfull login of disabled user (#78)
This commit introduces fix for scenario:
1. Root login disabled on dropbear
2. PAM authentication model enabled
While login as root user, after prompt for password
user is being notified about login failrue, but
after second attempt of prompt for password within
same session, login becames succesfull.
Signed-off-by: Pawel Rapkiewicz <[email protected]>
author | vincentto13 <33652988+vincentto13@users.noreply.github.com> |
---|---|
date | Wed, 20 Mar 2019 15:03:40 +0100 |
parents | a57822db3eac |
children |
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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; }