Mercurial > dropbear
annotate fuzzer-kexdh.c @ 1653:76189c9ffea2
External Public-Key Authentication API (#72)
* Implemented dynamic loading of an external plug-in shared library to delegate public key authentication
* Moved conditional compilation of the plugin infrastructure into the configure.ac script to be able to add -ldl to dropbear build only when the flag is enabled
* Added tags file to the ignore list
* Updated API to have the constructor to return function pointers in the pliugin instance. Added support for passing user name to the checkpubkey function. Added options to the session returned by the plugin and have dropbear to parse and process them
* Added -rdynamic to the linker flags when EPKA is enabled
* Changed the API to pass a previously created session to the checkPubKey function (created during preauth)
* Added documentation to the API
* Added parameter addrstring to plugin creation function
* Modified the API to retrieve the auth options. Instead of having them as field of the EPKASession struct, they are stored internally (plugin-dependent) in the plugin/session and retrieved through a pointer to a function (in the session)
* Changed option string to be a simple char * instead of unsigned char *
| author | fabriziobertocci <fabriziobertocci@gmail.com> |
|---|---|
| date | Wed, 15 May 2019 09:43:57 -0400 |
| parents | a57822db3eac |
| children |
| rev | line source |
|---|---|
| 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 } |