Mercurial > dropbear
annotate fuzzer-kexdh.c @ 1665:7c17995bcdfb
Improve address logging on early exit messages (#83)
Change 'Early exit' and 'Exit before auth' messages to include the IP
address & port as part of the message.
This allows log scanning utilities such as 'fail2ban' to obtain the
offending IP address as part of the failure event instead of extracting
the PID from the message and then scanning the log again for match
'child connection from' messages
Signed-off-by: Kevin Darbyshire-Bryant <[email protected]>
author | Kevin Darbyshire-Bryant <6500011+ldir-EDB0@users.noreply.github.com> |
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date | Wed, 18 Mar 2020 15:28:56 +0000 |
parents | a57822db3eac |
children |
rev | line source |
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1589 | 1 #include "fuzz.h" |
2 #include "session.h" | |
3 #include "fuzz-wrapfd.h" | |
4 #include "debug.h" | |
5 #include "runopts.h" | |
6 #include "algo.h" | |
7 #include "bignum.h" | |
8 | |
9 int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) { | |
10 static int once = 0; | |
11 static struct key_context* keep_newkeys = NULL; | |
1601
b711a8256919
reduce fuzzer-kexdh params count again, still hitting timeout
Matt Johnston <matt@ucc.asn.au>
parents:
1595
diff
changeset
|
12 /* number of generated parameters is limited by the timeout for the first run. |
b711a8256919
reduce fuzzer-kexdh params count again, still hitting timeout
Matt Johnston <matt@ucc.asn.au>
parents:
1595
diff
changeset
|
13 TODO move this to the libfuzzer initialiser function instead if the timeout |
b711a8256919
reduce fuzzer-kexdh params count again, still hitting timeout
Matt Johnston <matt@ucc.asn.au>
parents:
1595
diff
changeset
|
14 doesn't apply there */ |
b711a8256919
reduce fuzzer-kexdh params count again, still hitting timeout
Matt Johnston <matt@ucc.asn.au>
parents:
1595
diff
changeset
|
15 #define NUM_PARAMS 20 |
1589 | 16 static struct kex_dh_param *dh_params[NUM_PARAMS]; |
17 | |
18 if (!once) { | |
19 fuzz_common_setup(); | |
20 fuzz_svr_setup(); | |
21 | |
22 keep_newkeys = (struct key_context*)m_malloc(sizeof(struct key_context)); | |
23 keep_newkeys->algo_kex = fuzz_get_algo(sshkex, "diffie-hellman-group14-sha256"); | |
24 keep_newkeys->algo_hostkey = DROPBEAR_SIGNKEY_ECDSA_NISTP256; | |
25 ses.newkeys = keep_newkeys; | |
26 | |
27 /* Pre-generate parameters */ | |
28 int i; | |
29 for (i = 0; i < NUM_PARAMS; i++) { | |
30 dh_params[i] = gen_kexdh_param(); | |
31 } | |
32 | |
33 once = 1; | |
34 } | |
35 | |
36 if (fuzz_set_input(Data, Size) == DROPBEAR_FAILURE) { | |
37 return 0; | |
38 } | |
39 | |
40 m_malloc_set_epoch(1); | |
41 | |
42 if (setjmp(fuzz.jmp) == 0) { | |
43 /* Based on recv_msg_kexdh_init()/send_msg_kexdh_reply() | |
44 with DROPBEAR_KEX_NORMAL_DH */ | |
45 ses.newkeys = keep_newkeys; | |
46 | |
47 /* Choose from the collection of ecdh params */ | |
48 unsigned int e = buf_getint(fuzz.input); | |
49 struct kex_dh_param * dh_param = dh_params[e % NUM_PARAMS]; | |
50 | |
51 DEF_MP_INT(dh_e); | |
52 m_mp_init(&dh_e); | |
53 if (buf_getmpint(fuzz.input, &dh_e) != DROPBEAR_SUCCESS) { | |
54 dropbear_exit("Bad kex value"); | |
55 } | |
56 | |
1606
98d2b125eb89
kexhashbuf was much to small in kex fuzzers
Matt Johnston <matt@ucc.asn.au>
parents:
1601
diff
changeset
|
57 ses.kexhashbuf = buf_new(KEXHASHBUF_MAX_INTS); |
1589 | 58 kexdh_comb_key(dh_param, &dh_e, svr_opts.hostkey); |
59 | |
1609 | 60 mp_clear(ses.dh_K); |
1589 | 61 m_free(ses.dh_K); |
62 mp_clear(&dh_e); | |
63 | |
1609 | 64 buf_free(ses.hash); |
65 buf_free(ses.session_id); | |
66 /* kexhashbuf is freed in kexdh_comb_key */ | |
67 | |
1589 | 68 m_malloc_free_epoch(1, 0); |
69 } else { | |
70 m_malloc_free_epoch(1, 1); | |
71 TRACE(("dropbear_exit longjmped")) | |
72 /* dropbear_exit jumped here */ | |
73 } | |
74 | |
75 return 0; | |
76 } |