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lightning-bolts/03-transactions.md
2016-12-13 15:44:14 +01:00

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# BOLT #3: Bitcoin Transaction and Script Formats
This details the exact format of on-chain transactions, which both sides need to agree on to ensure signatures are valid. That is, the funding transaction output script, commitment transactions and the HTLC transactions.
## Transaction input and output ordering
Lexicographic ordering as per BIP 69.
## Use of segwit
Most transaction outputs used here are P2WSH outputs, the segwit version of P2SH. To spend such outputs, the last item on the witness stack must be the actual script that was used to generate the P2WSH output that is being spent. This last item has been omitted for brevity in the rest of this document.
## Funding Transaction Output
* The funding output script is a pay-to-witness-script-hash<sup>[BIP141](https://github.com/bitcoin/bips/blob/master/bip-0141.mediawiki#witness-program)</sup> to:
* `0 2 <key1> <key2> 2 OP_CHECKMULTISIG`
* Where `key1` is the numerically lesser of the two DER-encoded `funding-pubkey` and `key2` is the greater.
## Commitment Transaction
* version: 2
* locktime: upper 8 bits are zero, lower 24 bits are the lower 24 bits of the obscured commitment transaction number.
* txin count: 1
* `txin[0]` outpoint: `txid` and `output_index` from `funding_created` message
* `txin[0]` sequence: upper 8 bits are 0x80, lower 24 bits are upper 24 bits of the obscured commitment transaction number.
* `txin[0]` script bytes: 0
* `txin[0]` witness: `<signature-for-key1> <signature-for-key-2>`
The 48-bit commitment transaction number is obscured by `XOR` with the lower 48 bits of:
SHA256(payment-basepoint from open_channel || payment-basepoint from accept_channel)
This obscures the number of commitments made on the channel in the
case of unilateral close, yet still provides a useful index for both
nodes (who know the payment-basepoints) to quickly find a revoked
commitment transaction.
### Commitment Transaction Outputs
To allow an opportunity for penalty transactions in case of a revoked commitment transaction, all outputs which return funds to the owner of the commitment transaction (aka "local node") must be delayed for `to-self-delay` blocks. This delay is done in a second stage HTLC transaction (HTLC-success for HTLCs accepted by the local node, HTLC-timeout for HTLCs offered by the local node).
The reason for the separate transaction stage for HTLC outputs is so that HTLCs can time out or be fulfilled even though they are within the `to-self-delay` delay.
Otherwise the required minimum timeout on HTLCs is lengthened by this delay, causing longer timeouts for HTLCs traversing the network.
The amounts for each output are rounded down to whole satoshis. If this amount, minus the fees for the HTLC transaction is less than the `dust-limit-satoshis` set by the owner of the commitment transaction, the output is not produced (thus the funds add to fees).
#### To-Local Output
This output sends funds back to the owner of this commitment transaction, thus must be timelocked using `OP_CSV`. It can be claimed, without delay, by the other party if they know the revocation key. The output is a version 0 P2WSH, with a witness script:
OP_IF
# Penalty transaction
<revocation-pubkey>
OP_ELSE
`to-self-delay`
OP_CSV
OP_DROP
<local-delayedkey>
OP_ENDIF
OP_CHECKSIG
It is spent by a transaction with `nSequence` field set to `to-self-delay` (which can only be valid after that duration has passed), and witness script:
<local-delayedsig> 0
If a revoked commitment transaction is published, the other party can spend this output immediately with the following witness script:
<revocation-sig> 1
#### To-Remote Output
This output sends funds to the other peer, thus is a simple P2PKH to `remotekey`.
#### Offered HTLC Outputs
This output sends funds to a HTLC-timeout transaction after the HTLC timeout, or to the remote peer on successful payment preimage. The output is a P2WSH, with a witness script:
<remotekey> OP_SWAP
OP_SIZE 32 OP_EQUAL
OP_NOTIF
# To me via HTLC-timeout transaction (timelocked).
OP_DROP 2 OP_SWAP <localkey> 2 OP_CHECKMULTISIG
OP_ELSE
# To you with preimage.
OP_HASH160 <ripemd-of-payment-hash> OP_EQUALVERIFY
OP_CHECKSIG
OP_ENDIF
The remote node can redeem the HTLC with the scriptsig:
<remotesig> <payment-preimage>
Either node can use the HTLC-timeout transaction to time out the HTLC once the HTLC is expired, as shown below.
#### Received HTLC Outputs
This output sends funds to the remote peer after the HTLC timeout, or to an HTLC-success transaction with a successful payment preimage. The output is a P2WSH, with a witness script:
<remotekey> OP_SWAP
OP_SIZE 32 OP_EQUAL
OP_IF
# To me via HTLC-success transaction.
OP_HASH160 <ripemd-of-payment-hash> OP_EQUALVERIFY
2 OP_SWAP <localkey> 2 OP_CHECKMULTISIG
OP_ELSE
# To you after timeout.
OP_DROP <locktime> OP_CHECKLOCKTIMEVERIFY OP_DROP
OP_CHECKSIG
OP_ENDIF
To timeout the htlc, the remote node spends it with the scriptsig:
<remotesig> 0
To redeem the HTLC, the HTLC-success transaction is used as detailed below.
## HTLC-Timeout and HTLC-Success Transaction
These HTLC transactions are almost identical, except the HTLC-Timeout transaction is timelocked. This is also the transaction which can be spent by a valid penalty transaction.
* version: 2
* txin: the commitment transaction HTLC output.
* locktime: `0` for HTLC-Success, `htlc-timeout` for HTLC-Timeout.
* txin count: 1
* `txin[0]` outpoint: `txid` of the commitment transaction and `output_index` of the matching HTLC output for the HTLC transaction.
* `txin[0]` sequence: `0`
* `txin[0]` script bytes: `0`
* `txin[0]` witness stack: `0 <remotesig> <localsig> <payment-preimage>` for HTLC-Success, `0 <remotesig> <localsig> 0` for HTLC-Timeout.
* txout count: 1
* `txout[0]` amount: the HTLC amount minus fees (see [Fee Calculation](#fee-calculation)).
* `txout[0]` script: version 0 P2WSH with witness script as shown below.
The witness script for the output is:
OP_IF
# Penalty transaction
<revocation-pubkey>
OP_ELSE
`to-self-delay`
OP_CSV
OP_DROP
<local-delayedkey>
OP_ENDIF
OP_CHECKSIG
To spend this via penalty, the remote node uses a witness stack `<revocationsig> 1` and to collect the output the local node uses an input with nSequence `to-self-delay` and a witness stack `<local-delayedsig> 0`
## Fee Calculation
The fee calculation for both commitment transactions and HTLC
transactions is based on the current `feerate-per-kw` and the
*expected weight* of the transaction.
The actual and expected weight vary for several reasons:
* Bitcoin uses DER-encoded signatures which vary in size.
* Bitcoin also uses variable-length integers, so a large number of outputs will take 3 bytes to encode rather than 1.
* The `to-remote` output may be below the dust limit.
* The `to-local` output may be below the dust limit once fees are extracted.
Thus we use a simplified formula for *expected weight*, which assumes:
* Signatures are 73 bytes long (the maximum length)
* There is a small number of outputs (thus 1 byte to count them)
* There is always both a to-local output and a to-remote output.
The *expected weight* of a commitment transaction is calculated as follows:
p2wsh: 34 bytes
- OP_0: 1 byte
- OP_DATA: 1 byte (witness_script_SHA256 length)
- witness_script_SHA256: 32 bytes
p2wpkh: 22 bytes
- OP_0: 1 byte
- OP_DATA: 1 byte (public_key_HASH160 length)
- public_key_HASH160: 20 bytes
multi_sig: 71 bytes
- OP_2: 1 byte
- OP_DATA: 1 byte (pub_key_alice length)
- pub_key_alice: 33 bytes
- OP_DATA: 1 byte (pub_key_bob length)
- pub_key_bob: 33 bytes
- OP_2: 1 byte
- OP_CHECKMULTISIG: 1 byte
witness: 222 bytes
- number_of_witness_elements: 1 byte
- nil_length: 1 byte
- sig_alice_length: 1 byte
- sig_alice: 73 bytes
- sig_bob_length: 1 byte
- sig_bob: 73 bytes
- witness_script_length: 1 byte
- witness_script (multi_sig)
funding_input: 41 bytes
- previous_out_point: 36 bytes
- hash: 32 bytes
- index: 4 bytes
- var_int: 1 byte (script_sig length)
- script_sig: 0 bytes
- witness <---- we use "witness" instead of "script_sig" for
transaction validation, but "witness" is stored
separately and cost for it size is smaller. So
we separate the calculation of ordinary data
from witness data.
- sequence: 4 bytes
output_paying_to_us: 43 bytes
- value: 8 bytes
- var_int: 1 byte (pk_script length)
- pk_script (p2wsh): 34 bytes
output_paying_to_them: 31 bytes
- value: 8 bytes
- var_int: 1 byte (pk_script length)
- pk_script (p2wpkh): 22 bytes
htlc_output: 43 bytes
- value: 8 bytes
- var_int: 1 byte (pk_script length)
- pk_script (p2wsh): 34 bytes
witness_header: 2 bytes
- flag: 1 byte
- marker: 1 byte
commitment_transaction: 125 + 43 * num-htlc-outputs bytes
- version: 4 bytes
- witness_header <---- part of the witness data
- count_tx_in: 1 byte
- tx_in: 41 bytes
funding_input
- count_tx_out: 1 byte
- tx_out: 74 + 43 * num-htlc-outputs bytes
output_paying_to_them,
output_paying_to_us,
....htlc_output's...
- lock_time: 4 bytes
Multiplying non-witness data by 4, this gives a weight of:
// 500 + 172 * num-htlc-outputs weight
commitment_transaction_weight = 4 * commitment_transaction
// 224 weight
witness_weight = witness_header + witness
overall_weight = 500 + 172 * num-htlc-outputs + 224 weight
The *expected weight* of an HTLC transaction is calculated as follows:
accepted_htlc_script: 109 bytes
- OP_DATA: 1 byte (remotekey length)
- remotekey: 33 bytes
- OP_SWAP: 1 byte
- OP_SIZE: 1 byte
- 32: 1 byte
- OP_EQUAL: 1 byte
- OP_IF: 1 byte
- OP_HASH160: 1 byte
- OP_DATA: 1 byte (ripemd-of-payment-hash length)
- ripemd-of-payment-hash: 20 bytes
- OP_EQUALVERIFY: 1 byte
- 2: 1 byte
- OP_SWAP: 1 byte
- OP_DATA: 1 byte (localkey length)
- localkey: 33 bytes
- 2: 1 byte
- OP_CHECKMULTISIG: 1 byte
- OP_ELSE: 1 byte
- OP_DROP: 1 byte
- OP_PUSHDATA2: 1 byte (locktime length)
- locktime: 2 bytes
- OP_CHECKLOCKTIMEVERIFY: 1 byte
- OP_DROP: 1 byte
- OP_CHECKSIG: 1 byte
- OP_ENDIF: 1 byte
offered_htlc_script: 104 bytes
- OP_DATA: 1 byte (remotekey length)
- remotekey: 33 bytes
- OP_SWAP: 1 byte
- OP_SIZE: 1 byte
- 32: 1 byte
- OP_EQUAL: 1 byte
- OP_NOTIF: 1 byte
- OP_DROP: 1 byte
- 2: 1 byte
- OP_SWAP: 1 byte
- OP_DATA: 1 byte (localkey length)
- localkey: 33 bytes
- 2: 1 byte
- OP_CHECKMULTISIG: 1 byte
- OP_ELSE: 1 byte
- OP_HASH160: 1 byte
- OP_DATA: 1 byte (ripemd-of-payment-hash length)
- ripemd-of-payment-hash: 20 bytes
- OP_EQUALVERIFY: 1 byte
- OP_CHECKSIG: 1 byte
- OP_ENDIF: 1 byte
timeout_witness: 256 bytes
- number_of_witness_elements: 1 byte
- nil_length: 1 byte
- sig_alice_length: 1 byte
- sig_alice: 73 bytes
- sig_bob_length: 1 byte
- sig_bob: 73 bytes
- nil_length: 1 byte
- witness_script_length: 1 byte
- witness_script (offered_htlc_script)
success_witness: 293 bytes
- number_of_witness_elements: 1 byte
- nil_length: 1 byte
- sig_alice_length: 1 byte
- sig_alice: 73 bytes
- sig_bob_length: 1 byte
- sig_bob: 73 bytes
- preimage_length: 1 byte
- preimage: 32 bytes
- witness_script_length: 1 byte
- witness_script (accepted_htlc_script)
commitment_input: 41 bytes
- previous_out_point: 36 bytes
- hash: 32 bytes
- index: 4 bytes
- var_int: 1 byte (script_sig length)
- script_sig: 0 bytes
- witness (success_witness or timeout_witness)
- sequence: 4 bytes
htlc_tx_output: 43 bytes
- value: 8 bytes
- var_int: 1 byte (pk_script length)
- pk_script (p2wsh): 34 bytes
htlc_transaction:
- version: 4 bytes
- witness_header <---- part of the witness data
- count_tx_in: 1 byte
- tx_in: 41 bytes
commitment_input
- count_tx_out: 1 byte
- tx_out: 43
htlc_tx_output
- lock_time: 4 bytes
Multiplying non-witness data by 4, this gives a weight of 376. Adding
the witness data for each case (256 + 2 for HTLC-timeout, 293 + 2 for
HTLC-success) gives a weight of:
634 (HTLC-timeout)
671 (HTLC-success)
### Requirements
The fee for an HTLC-timeout transaction MUST BE calculated to match:
1. Multiply `feerate-per-kw` by 634 and divide by 1024 (rounding down).
The fee for an HTLC-success transaction MUST BE calculated to match:
1. Multiply `feerate-per-kw` by 671 and divide by 1024 (rounding down).
The fee for a commitment transaction MUST BE calculated to match:
1. Start with `weight` = 724, and `fee` = 0.
3. For every offered HTLC, if the HTLC amount plus the HTLC-timeout
transaction fee is greater or equal to the local node's
`dust-limit-satoshis`, then add 172 to `weight`, otherwise add
the HTLC amount to `fee`.
4. For every accepted HTLC, if the HTLC amount plus the HTLC-success
transaction fee is greater or equal to the local node's
`dust-limit-satoshis`, then add 172 to `weight`, otherwise add
the HTLC amount to `fee`.
5. Multiply `feerate-per-kw` by `weight`, divide by 1024 (rounding down),
and add to `fee`.
# Key Derivation
Each commitment transaction uses a unique set of keys; `localkey` and `remotekey`. The HTLC-success and HTLC-timeout transactions use `local-delayedkey` and `revocationkey`. These are changed every time depending on the
`per-commitment-point`.
Keys change because of the desire for trustless outsourcing of
watching for revoked transactions; a _watcher_ should not be able to
determine what the contents of commitment transaction is, even if
given the transaction ID to watch for and can make a resonable guess
as to what HTLCs and balances might be included. Nonetheless, to
avoid storage for every commitment transaction, it can be given the
`per-commitment-secret` values (which can be stored compactly) and the
`revocation-basepoint` and `delayed-payment-basepoint` to regnerate
the scripts required for the penalty transaction: it need only be
given (and store) the signatures for each penalty input.
Changing the `localkey` and `remotekey` every time ensures that commitment transaction id cannot be guessed: Every commitment transaction uses one of these in its output script. Splitting the `local-delayedkey` which is required for the penalty transaction allows that to be shared with the watcher without revealing `localkey`; even if both peers use the same watcher, nothing is revealed.
Finally, even in the case of normal unilateral close, the HTLC-success
and/or HTLC-timeout transactions do not reveal anything to the
watcher, as it does not know the corresponding `per-commitment-secret` and
cannot relate the `local-delayedkey` or `revocationkey` with
their bases.
For efficiency, keys are generated from a series of per-commitment secrets which are generated from a single seed, allowing the receiver to compactly store them (see [below](#efficient-per-commitment-secret-storage)).
## `localkey`, `remotekey`, `local-delayedkey` and `remote-delayedkey` Derivation
These keys are simply generated by addition from their base points:
pubkey = basepoint + SHA256(per-commitment-point || basepoint)*G
The `localkey` uses the local node's `payment-basepoint`, `remotekey`
uses the remote node's `payment-basepoint`, the `local-delayedkey`
uses the local node's `delayed-payment-basepoint`, and the
`remote-delayedkey` uses the remote node's
`delayed-payment-basepoint`.
The correspoding private keys can be derived similarly if the basepoint
secrets are known (i.e., `localkey` and `local-delayedkey` only):
secretkey = basepoint-secret + SHA256(per-commitment-point || basepoint)
## `revocationkey` Derivation
The revocationkey is a blinded key: the remote node provides the base,
and the local node provides the blinding factor which it later
reveals, so the remote node can use the secret revocationkey for a
penalty transaction.
The `per-commitment-point` is generated using EC multiplication:
per-commitment-point = per-commitment-secret * G
And this is used to derive the revocation key from the remote node's
`revocation-basepoint`:
revocationkey = revocation-basepoint * SHA256(revocation-basepoint || per-commitment-point) + per-commitment-point*SHA256(per-commitment-point || revocation-basepoint)
This construction ensures that neither the node providing the
basepoint nor the node providing the `per-commitment-point` can know the
private key without the other node's secret.
### Per-commitment Secret Requirements
A node MUST select an unguessable 256-bit seed for each connection,
and MUST NOT reveal the seed. Up to 2^48-1 per-commitment secrets can be
generated; the first secret used MUST be index 281474976710655, and
then the index decremented.
The I'th secret P MUST match the output of this algorithm:
generate_from_seed(seed, I):
P = seed
for B in 0 to 47:
if B set in I:
flip(B) in P
P = SHA256(P)
return P
Where "flip(B)" alternates the B'th least significant bit in the value P.
The receiving node MAY store all previous per-commitment secrets, or
MAY calculate it from a compact representation as described below.
### Efficient Per-commitment Secret Storage
The receiver of a series of secrets can store them compactly in an
array of 49 (value,index) pairs. This is because given a secret on a
2^X boundary, we can derive all secrets up to the next 2^X boundary,
and we always receive secrets in descending order starting at
`0xFFFFFFFFFFFF`.
In binary, it's helpful to think of any index in terms of a *prefix*,
followed by some trailing zeroes. You can derive the secret for any
index which matches this *prefix*.
For example, secret `0xFFFFFFFFFFF0` allows us to derive secrets for
`0xFFFFFFFFFFF1` through `0xFFFFFFFFFFFF` inclusive. Secret `0xFFFFFFFFFF08`
allows us to derive secrets `0xFFFFFFFFFF09` through `0xFFFFFFFFFF0F`
inclusive.
We do this using a slight generalization of `generate_from_seed` above:
# Return I'th secret given base secret whose index has bits..47 the same.
derive_secret(base, bits, I):
P = base
for B in 0 to bits:
if B set in I:
flip(B) in P
P = SHA256(P)
return P
We need only save one secret for each unique prefix; in effect we can
count the number of trailing zeros, and that determines where in our
storage array we store the secret:
# aka. count trailing zeroes
where_to_put_secret(I):
for B in 0 to 47:
if testbit(I) in B == 1:
return B
# I = 0, this is the seed.
return 48
We also need to double-check that all previous secrets derive correctly,
otherwise the secrets were not generated from the same seed:
insert_secret(secret, I):
B = where_to_put_secret(secret, I)
# This tracks the index of the secret in each bucket as we traverse.
for b in 0 to B:
if derive_secret(secret, B, known[b].index) != known[b].secret:
error The secret for I is incorrect
return
# Assuming this automatically extends known[] as required.
known[B].index = I
known[B].secret = secret
Finally, if we are asked to derive secret at index `I`, we need to
figure out which known secret we can derive it from. The simplest
method is iterating over all the known secrets, and testing if we
can derive from it:
derive_old_secret(I):
for b in 0 to len(secrets):
# Mask off the non-zero prefix of the index.
MASK = ~((1 << b)-1)
if (I & MASK) == secrets[b].index:
return derive_secret(known, i, I)
error We haven't received index I yet.
This looks complicated, but remember that the index in entry `b` has
`b` trailing zeros; the mask and compare is just seeing if the index
at each bucket is a prefix of the index we want.
# Appendix A: Per-commitment Secret Generation Test Vectors
These test the generation algorithm which all nodes use.
## Generation tests
name: generate_from_seed 0 final node
seed: 0x0000000000000000000000000000000000000000000000000000000000000000
I: 281474976710655
output: 0x02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148
name: generate_from_seed FF final node
seed: 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
I: 281474976710655
output: 0x7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc
name: generate_from_seed FF alternate bits 1
seed: 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
I: 0xaaaaaaaaaaa
output: 0x56f4008fb007ca9acf0e15b054d5c9fd12ee06cea347914ddbaed70d1c13a528
name: generate_from_seed FF alternate bits 2
seed: 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
I: 0x555555555555
output: 0x9015daaeb06dba4ccc05b91b2f73bd54405f2be9f217fbacd3c5ac2e62327d31
name: generate_from_seed 01 last nontrivial node
seed: 0x0101010101010101010101010101010101010101010101010101010101010101
I: 1
output: 0x915c75942a26bb3a433a8ce2cb0427c29ec6c1775cfc78328b57f6ba7bfeaa9c
## Storage tests
These test the optional compact storage system. In many cases, an
incorrect entry cannot be determined until its parent is revealed; we
specifically corrupt an entry and all its children (except for the
last test, which would require another 8 samples to be detected). For
these tests we use a seed of `0xFFF...FF` and incorrect entries are
seeded with `0x000...00`.
name: insert_secret correct sequence
I: 281474976710655
secret: 0x7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc
output: OK
I: 281474976710654
secret: 0xc7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964
output: OK
I: 281474976710653
secret: 0x2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8
output: OK
I: 281474976710652
secret: 0x27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116
output: OK
I: 281474976710651
secret: 0xc65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd
output: OK
I: 281474976710650
secret: 0x969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2
output: OK
I: 281474976710649
secret: 0xa5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32
output: OK
I: 281474976710648
secret: 0x05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17
output: OK
name: insert_secret #1 incorrect
I: 281474976710655
secret: 0x02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148
output: OK
I: 281474976710654
secret: 0xc7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964
output: ERROR
name: insert_secret #2 incorrect (#1 derived from incorrect)
I: 281474976710655
secret: 0x02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148
output: OK
I: 281474976710654
secret: 0xdddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3
output: OK
I: 281474976710653
secret: 0x2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8
output: OK
I: 281474976710652
secret: 0x27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116
output: ERROR
name: insert_secret #3 incorrect
I: 281474976710655
secret: 0x7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc
output: OK
I: 281474976710654
secret: 0xc7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964
output: OK
I: 281474976710653
secret: 0xc51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a
output: OK
I: 281474976710652
secret: 0x27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116
output: ERROR
name: insert_secret #4 incorrect (1,2,3 derived from incorrect)
I: 281474976710655
secret: 0x02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148
output: OK
I: 281474976710654
secret: 0xdddc3a8d14fddf2b68fa8c7fbad2748274937479dd0f8930d5ebb4ab6bd866a3
output: OK
I: 281474976710653
secret: 0xc51a18b13e8527e579ec56365482c62f180b7d5760b46e9477dae59e87ed423a
output: OK
I: 281474976710652
secret: 0xba65d7b0ef55a3ba300d4e87af29868f394f8f138d78a7011669c79b37b936f4
output: OK
I: 281474976710651
secret: 0xc65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd
output: OK
I: 281474976710650
secret: 0x969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2
output: OK
I: 281474976710649
secret: 0xa5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32
output: OK
I: 281474976710648
secret: 0x05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17
output: ERROR
name: insert_secret #5 incorrect
I: 281474976710655
secret: 0x7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc
output: OK
I: 281474976710654
secret: 0xc7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964
output: OK
I: 281474976710653
secret: 0x2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8
output: OK
I: 281474976710652
secret: 0x27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116
output: OK
I: 281474976710651
secret: 0x631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6
output: OK
I: 281474976710650
secret: 0x969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2
output: ERROR
name: insert_secret #6 incorrect (5 derived from incorrect)
I: 281474976710655
secret: 0x7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc
output: OK
I: 281474976710654
secret: 0xc7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964
output: OK
I: 281474976710653
secret: 0x2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8
output: OK
I: 281474976710652
secret: 0x27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116
output: OK
I: 281474976710651
secret: 0x631373ad5f9ef654bb3dade742d09504c567edd24320d2fcd68e3cc47e2ff6a6
output: OK
I: 281474976710650
secret: 0xb7e76a83668bde38b373970155c868a653304308f9896692f904a23731224bb1
output: OK
I: 281474976710649
secret: 0xa5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32
output: OK
I: 281474976710648
secret: 0x05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17
output: ERROR
name: insert_secret #7 incorrect
I: 281474976710655
secret: 0x7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc
output: OK
I: 281474976710654
secret: 0xc7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964
output: OK
I: 281474976710653
secret: 0x2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8
output: OK
I: 281474976710652
secret: 0x27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116
output: OK
I: 281474976710651
secret: 0xc65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd
output: OK
I: 281474976710650
secret: 0x969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2
output: OK
I: 281474976710649
secret: 0xe7971de736e01da8ed58b94c2fc216cb1dca9e326f3a96e7194fe8ea8af6c0a3
output: OK
I: 281474976710648
secret: 0x05cde6323d949933f7f7b78776bcc1ea6d9b31447732e3802e1f7ac44b650e17
output: ERROR
name: insert_secret #8 incorrect
I: 281474976710655
secret: 0x7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc
output: OK
I: 281474976710654
secret: 0xc7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964
output: OK
I: 281474976710653
secret: 0x2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8
output: OK
I: 281474976710652
secret: 0x27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116
output: OK
I: 281474976710651
secret: 0xc65716add7aa98ba7acb236352d665cab17345fe45b55fb879ff80e6bd0c41dd
output: OK
I: 281474976710650
secret: 0x969660042a28f32d9be17344e09374b379962d03db1574df5a8a5a47e19ce3f2
output: OK
I: 281474976710649
secret: 0xa5a64476122ca0925fb344bdc1854c1c0a59fc614298e50a33e331980a220f32
output: OK
I: 281474976710648
secret: 0xa7efbc61aac46d34f77778bac22c8a20c6a46ca460addc49009bda875ec88fa4
output: ERROR
# References
# Authors
FIXME
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