Add a fuzz test for BOLT 8 message encryption and decryption. The fuzz
test is based on the unit test at common/test/run-cryptomsg.c and uses a
static initial state with fuzzer-generated messages to encrypt or
decrypt.
This header will be used by multiple fuzz targets to fuzz Acts 1, 2, and
3 of the BOLT 8 handshake.
We could make this header into a full library, but considering its
narrow use let's try not to over-engineer things.
Now we wire in the code which gathers configvars and parses from there;
lightningd keeps the array of configuration variables for future use.
Note that lightning-cli also needs to read the config, but it has its
own options (including short ones!) and doesn't want to use this
configvar mechanism, so we have a different API for that now.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We were passing a max_output_len that was too small, so every call to
bech32_encode was failing. Now we set max_output_len to the full size of
bech32_str.
We need to check that the key is valid for two reasons:
1) towire_ext_key() aborts if the key is invalid
2) fromwire_ext_key() doesn't check the parsed key for validity
Since bip32_key_get_fingerprint() fails if the key is invalid, we can
call it first to guarantee the key is valid before serializing.
These corpora were generated with default libFuzzer flags with 30+ hours
of CPU time, and then minimized with:
./fuzz-TARGET -merge=1 -shuffle=0 -prefer_small=1 -use_value_profile=1 corpora/fuzz-TARGET UNMINIMIZED_CORPUS
pubkey_from_hexstr() was failing, which we didn't notice because we
weren't checking the return value. The problem was that we were passing
it a strlen that was half the actual length.
Relevant error:
[libsecp256k1] illegal argument: !secp256k1_fe_is_zero(&ge->x)
==417723== ERROR: libFuzzer: deadly signal
#7 0x7f5deaacc7fb in abort
#8 0x51b0b0 in secp256k1_default_illegal_callback_fn secp256k1.c
#9 0x51bd8e in secp256k1_ec_pubkey_serialize
#10 0x4e235b in pubkey_to_der bitcoin/pubkey.c:29:7
#11 0x4e2941 in pubkey_cmp bitcoin/pubkey.c:89:2
#12 0x4e333d in bitcoin_redeem_2of2 bitcoin/script.c:144:6
#13 0x4f1396 in run tests/fuzz/fuzz-close_tx.c:78:19
The issue is that common_setup() wasn't called by the fuzz target,
leaving secp256k1_ctx as NULL.
UBSan error:
$ UBSAN_OPTIONS="print_stacktrace=1:halt_on_error=1" \
./fuzz-channel_id crash-1575b41ef09e62e4c09c165e6dc037a110b113f2
INFO: Running with entropic power schedule (0xFF, 100).
INFO: Seed: 1153355603
INFO: Loaded 1 modules (25915 inline 8-bit counters): 25915 [0x563bae7ac3a8, 0x563bae7b28e3),
INFO: Loaded 1 PC tables (25915 PCs): 25915 [0x563bae7b28e8,0x563bae817c98),
./fuzz-channel_id: Running 1 inputs 1 time(s) each.
Running: crash-1575b41ef09e62e4c09c165e6dc037a110b113f2
bitcoin/pubkey.c:22:33: runtime error: null pointer passed as argument 1, which is declared to never be null
external/libwally-core/src/secp256k1/include/secp256k1.h:373:3: note: nonnull attribute specified here
#0 0x563bae41e3db in pubkey_from_der bitcoin/pubkey.c:19:7
#1 0x563bae4205e0 in fromwire_pubkey bitcoin/pubkey.c:111:7
#2 0x563bae46437c in run tests/fuzz/fuzz-channel_id.c:42:3
#3 0x563bae2f6016 in LLVMFuzzerTestOneInput tests/fuzz/libfuzz.c:23:2
#4 0x563bae20a450 in fuzzer::Fuzzer::ExecuteCallback(unsigned char const*, unsigned long)
#5 0x563bae1f4c3f in fuzzer::RunOneTest(fuzzer::Fuzzer*, char const*, unsigned long)
#6 0x563bae1fa6e6 in fuzzer::FuzzerDriver(int*, char***, int (*)(unsigned char const*, unsigned long))
#7 0x563bae223052 in main (tests/fuzz/fuzz-channel_id+0x181052) (BuildId: f7f56e14ffc06df54ab732d79ea922e773de1f25)
#8 0x7fa7fa113082 in __libc_start_main
#9 0x563bae1efbdd in _start
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior bitcoin/pubkey.c:22:33 in
No tests currently use it, and if they do we'll want to do some
per-test objects. Otherwise, we are about it introduce a dependency
on common/json_filter.o, which is a can of worms.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
And turn "" includes into full-path (which makes it easier to put
config.h first, and finds some cases check-includes.sh missed
previously).
config.h sets _GNU_SOURCE which really needs to be done before any
'#includes': we mainly got away with it with glibc, but other platforms
like Alpine may have stricter requirements.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
