And now I do now feel a bit more "legendary".
Topic: What exactly is "signed" for each UTXO in a Bitcoin tx? (Read 1029 times)
My badge of honor: https://blockchain.info/tx/9615d019abcb8ad4aa1361deeb6972c3afbecf97841ab07afbc6eaac5608813b
And now I do now feel a bit more "legendary".
And now I do now feel a bit more "legendary".
My suggestion is (not for you, but for everyone):
Do not waste blockchain space with your test transactions!
Use testnet instead!
(And send main-net coins directly to my adderss)
Do not waste blockchain space with your test transactions!
Use testnet instead!
(And send main-net coins directly to my adderss)
Damn - stupid coding mistakes. 
Those "sizeof( hash )" should have been c_num_hash_bytes instead. Doh!
Anyway here is my first self-created "signed Bitcoin tx" is as follows:
01000000013c9eab4935d1b8fe2bad3af1c443c2c61ab8212c3f45c2ba59ff4a2e93c481e200000 0006b483045022100d06e7cf940032fdbba04a35b07bfec4359c79936e00c2b31c78b0ec6d1fe79 960220269065708cec6c3436dc4a65b7841e09eaf9d1eec98a52930ee747290cb7b22b012103bd6 f03d746e0127a45c6f8ba39326da9d7a00efce7a74828e2e5bef85e37f8feffffffff01204e0000 000000001976a91406c1991c6466a550b66931ea48970cfd17ff51b388ac00000000
Quite a feeling of achievement (it did take me a whole day).
Thanks a lot for the help @amaclin (if nothing else you helped me to "keep trying until I conquered it").
Those "sizeof( hash )" should have been c_num_hash_bytes instead. Doh!
Anyway here is my first self-created "signed Bitcoin tx" is as follows:
01000000013c9eab4935d1b8fe2bad3af1c443c2c61ab8212c3f45c2ba59ff4a2e93c481e200000 0006b483045022100d06e7cf940032fdbba04a35b07bfec4359c79936e00c2b31c78b0ec6d1fe79 960220269065708cec6c3436dc4a65b7841e09eaf9d1eec98a52930ee747290cb7b22b012103bd6 f03d746e0127a45c6f8ba39326da9d7a00efce7a74828e2e5bef85e37f8feffffffff01204e0000 000000001976a91406c1991c6466a550b66931ea48970cfd17ff51b388ac00000000
Code:
01000000013c9eab4935d1b8fe2bad3af1c443c2c61ab8212c3f45c2ba59ff4a2e93c481e2000000006b483045022100d06e7cf940032fdbba04a35b07bfec4359c79936e00c2b31c78b0ec6d1fe79960220269065708cec6c3436dc4a65b7841e09eaf9d1eec98a52930ee747290cb7b22b012103bd6f03d746e0127a45c6f8ba39326da9d7a00efce7a74828e2e5bef85e37f8feffffffff01204e0000000000001976a91406c1991c6466a550b66931ea48970cfd17ff51b388ac00000000
Quite a feeling of achievement (it did take me a whole day).
Thanks a lot for the help @amaclin (if nothing else you helped me to "keep trying until I conquered it").
My code for generating the sig is as follows:
I have then checked whether the sig should be valid with this function:
It tells me it should be okay (so again I can only think I have got something wrong with "what I signed").
Code:
const int c_num_hash_bytes = 32;
void sign_message( const unsigned char hash[ c_num_hash_bytes ], vector< unsigned char >& signature )
{
ECDSA_SIG* p_sig = ECDSA_do_sign( &hash[ 0 ], sizeof( hash ), p_key );
if( !p_sig )
throw runtime_error( "unexpected failure for ECDSA_do_sign in sign_message" );
signature.clear( );
unsigned int size = ECDSA_size( p_key );
signature.resize( size );
unsigned char* p = &signature[ 0 ];
size = i2d_ECDSA_SIG( p_sig, &p );
signature.resize( size );
ECDSA_SIG_free( p_sig );
}
void sign_message( const unsigned char hash[ c_num_hash_bytes ], vector< unsigned char >& signature )
{
ECDSA_SIG* p_sig = ECDSA_do_sign( &hash[ 0 ], sizeof( hash ), p_key );
if( !p_sig )
throw runtime_error( "unexpected failure for ECDSA_do_sign in sign_message" );
signature.clear( );
unsigned int size = ECDSA_size( p_key );
signature.resize( size );
unsigned char* p = &signature[ 0 ];
size = i2d_ECDSA_SIG( p_sig, &p );
signature.resize( size );
ECDSA_SIG_free( p_sig );
}
I have then checked whether the sig should be valid with this function:
Code:
bool verify_signature( const unsigned char hash[ c_num_hash_bytes ], vector< unsigned char >& signature )
{
bool okay = false;
if( ECDSA_verify( 0, &hash[ 0 ], sizeof( hash ), &signature[ 0 ], signature.size( ), p_key ) == 1 )
okay = true;
return okay;
}
{
bool okay = false;
if( ECDSA_verify( 0, &hash[ 0 ], sizeof( hash ), &signature[ 0 ], signature.size( ), p_key ) == 1 )
okay = true;
return okay;
}
It tells me it should be okay (so again I can only think I have got something wrong with "what I signed").
So I worked out I had screwed up with the signature generation.
The latest version I've tried is now this:
But it still doesn't like the sig.
The latest version I've tried is now this:
Code:
01000000013c9eab4935d1b8fe2bad3af1c443c2c61ab8212c3f45c2ba59ff4a2e93c481e2000000006b483045022100dba294c0766ff7d2eb9e308c13ec22da1ec8398ecb20111ead35c3776796983402207feaef74dbefeffe840a570ce7045d5e5e3f2c7dbd63ef16e7da841f2c8eda24012103bd6f03d746e0127a45c6f8ba39326da9d7a00efce7a74828e2e5bef85e37f8feffffffff01204e0000000000001976a91406c1991c6466a550b66931ea48970cfd17ff51b388ac00000000
But it still doesn't like the sig.
ok, data looks correct
And I got the same hash as yours but in different byte order "c279b67fa34c6aa2062bb2668dd45b43f8112208b5454f89b90538be907e853f"
(ok, my bytes are reversed (as all in bitcoin), yours are fine)
Code:
version 01000000
inputs 01
hash 3c9e ab49 35d1 b8fe-2bad 3af1 c443 c2c6-1ab8 212c 3f45 c2ba-59ff 4a2e 93c4 81e2
index 00000000
len 19
script 76a914 3a89c372f5308cb58828979bb624f7e8822672ed88ac
seq ffff ffff
outs 01
value 204e000000000000
output 1976a91406c1991c6466a550b66931ea48970cfd17ff51b388ac
lock 00000000
type 01000000
inputs 01
hash 3c9e ab49 35d1 b8fe-2bad 3af1 c443 c2c6-1ab8 212c 3f45 c2ba-59ff 4a2e 93c4 81e2
index 00000000
len 19
script 76a914 3a89c372f5308cb58828979bb624f7e8822672ed88ac
seq ffff ffff
outs 01
value 204e000000000000
output 1976a91406c1991c6466a550b66931ea48970cfd17ff51b388ac
lock 00000000
type 01000000
And I got the same hash as yours but in different byte order "c279b67fa34c6aa2062bb2668dd45b43f8112208b5454f89b90538be907e853f"
(ok, my bytes are reversed (as all in bitcoin), yours are fine)
sorry, i am wrong
wait please
wait please
No worries at all - am very glad for your help.
Okay so I now have this being signed:
01000000013c9eab4935d1b8fe2bad3af1c443c2c61ab8212c3f45c2ba59ff4a2e93c481e200000 00000ffffffff01204e0000000000001976a91406c1991c6466a5
50b66931ea48970cfd17ff51b388ac0000000001000000
with the final hash as: 6ad11c524c8ffa782800d4ff8c98a174ceff1f1004a497a8f8f836a7ed15aacf
It is still failing with an invalid sig.
01000000013c9eab4935d1b8fe2bad3af1c443c2c61ab8212c3f45c2ba59ff4a2e93c481e200000 00000ffffffff01204e0000000000001976a91406c1991c6466a5
50b66931ea48970cfd17ff51b388ac0000000001000000
Code:
01000000013c9eab4935d1b8fe2bad3af1c443c2c61ab8212c3f45c2ba59ff4a2e93c481e20000000000ffffffff01204e0000000000001976a91406c1991c6466a550b66931ea48970cfd17ff51b388ac0000000001000000
with the final hash as: 6ad11c524c8ffa782800d4ff8c98a174ceff1f1004a497a8f8f836a7ed15aacf
It is still failing with an invalid sig.
sorry, i am wrong
wait please
wait please
I do see three lines and I do not understand where are they from.
Please post the data, which you pass to sha256d method
...
Post them here.
Please post the data, which you pass to sha256d method
...
Post them here.
These were the bytes I signed (repeated in a "code" if that might make it easier for copy and paste):
01000000013c9eab4935d1b8fe2bad3af1c443c2c61ab8212c3f45c2ba59ff4a2e93c481e200000 0001976a9143a89c372f5308cb58828
979bb624f7e8822672ed88acffffffff01204e0000000000001976a91406c1991c6466a550b6693 1ea48970cfd17ff51b388ac0000000001000000
Code:
01000000013c9eab4935d1b8fe2bad3af1c443c2c61ab8212c3f45c2ba59ff4a2e93c481e2000000001976a9143a89c372f5308cb58828979bb624f7e8822672ed88acffffffff01204e0000000000001976a91406c1991c6466a550b66931ea48970cfd17ff51b388ac0000000001000000
The final hash I got for this is: 3f857e90be3805b9894f45b5082211f8435bd48d66b22b06a26a4ca37fb679c2
I guess that the bytes that I signed were somehow incorrect
Post them here.
Hmm... so it would appear that my sig is invalid so somehow I guess that the bytes that I signed were somehow incorrect - anyone see what I missed?
Thanks for that (it was helpful) and I think I am "very close" with this attempt:
01000000013c9eab4935d1b8fe2bad3af1c443c2c61ab8212c3f45c2ba59ff4a2e93c481e200000 0006c4930460221008acf9a9426220a6447d4e7062e796813b39208d242e4ae467d69b5804a25db 150221008b3d68c9b64517c4c011d3074c4cc04196f51f686178d59f11ae022a84b3574e012103b d6f03d746e0127a45c6f8ba39326da9d7a00efce7a74828e2e5bef85e37f8feffffffff01204e00 00000000001976a91406c1991c6466a550b66931ea48970cfd17ff51b388ac00000000
Code:
01000000013c9eab4935d1b8fe2bad3af1c443c2c61ab8212c3f45c2ba59ff4a2e93c481e2000000006c4930460221008acf9a9426220a6447d4e7062e796813b39208d242e4ae467d69b5804a25db150221008b3d68c9b64517c4c011d3074c4cc04196f51f686178d59f11ae022a84b3574e012103bd6f03d746e0127a45c6f8ba39326da9d7a00efce7a74828e2e5bef85e37f8feffffffff01204e0000000000001976a91406c1991c6466a550b66931ea48970cfd17ff51b388ac00000000
But alas it is rejected (-22).
It appears to decode fine so am wondering whether it is the sig that I've got wrong or if it is something else?
Code:
{
"lock_time":0,
"inputs":[
{
"prev_out":{
"index":0,
"hash":"e281c4932e4aff59bac2453f2c21b81ac6c243c4f13aad2bfeb8d13549ab9e3c"
},
"script":"4930460221008acf9a9426220a6447d4e7062e796813b39208d242e4ae467d69b5804a25db150221008b3d68c9b64517c4c011d3074c4cc04196f51f686178d59f11ae022a84b3574e012103bd6f03d746e0127a45c6f8ba39326da9d7a00efce7a74828e2e5bef85e37f8fe"
}
],
"vout_sz":1,
"hash":"62d03bf1444455ce2ff343a8f0e56b705b9ed4558768854f6e700e8a7451b787",
"vin_sz":1,
"out":[
{
"address":"1ciyam3htJit1feGa26p2wQ4aw6KFTejU",
"script_string":"OP_DUP OP_HASH160 06c1991c6466a550b66931ea48970cfd17ff51b3 OP_EQUALVERIFY OP_CHECKSIG",
"value":20000,
"script":"76a91406c1991c6466a550b66931ea48970cfd17ff51b388ac"
}
],
"size":193,
"version":1
}
"lock_time":0,
"inputs":[
{
"prev_out":{
"index":0,
"hash":"e281c4932e4aff59bac2453f2c21b81ac6c243c4f13aad2bfeb8d13549ab9e3c"
},
"script":"4930460221008acf9a9426220a6447d4e7062e796813b39208d242e4ae467d69b5804a25db150221008b3d68c9b64517c4c011d3074c4cc04196f51f686178d59f11ae022a84b3574e012103bd6f03d746e0127a45c6f8ba39326da9d7a00efce7a74828e2e5bef85e37f8fe"
}
],
"vout_sz":1,
"hash":"62d03bf1444455ce2ff343a8f0e56b705b9ed4558768854f6e700e8a7451b787",
"vin_sz":1,
"out":[
{
"address":"1ciyam3htJit1feGa26p2wQ4aw6KFTejU",
"script_string":"OP_DUP OP_HASH160 06c1991c6466a550b66931ea48970cfd17ff51b3 OP_EQUALVERIFY OP_CHECKSIG",
"value":20000,
"script":"76a91406c1991c6466a550b66931ea48970cfd17ff51b388ac"
}
],
"size":193,
"version":1
}
The sig is applied to two SHA256s of the following:
01000000013c9eab4935d1b8fe2bad3af1c443c2c61ab8212c3f45c2ba59ff4a2e93c481e200000 0001976a9143a89c372f5308cb58828979bb624f7e8822672ed88acffffffff01204e0000000000 001976a91406c1991c6466a550b66931ea48970cfd17ff51b388ac0000000001000000
Code:
01000000013c9eab4935d1b8fe2bad3af1c443c2c61ab8212c3f45c2ba59ff4a2e93c481e2000000001976a9143a89c372f5308cb58828979bb624f7e8822672ed88acffffffff01204e0000000000001976a91406c1991c6466a550b66931ea48970cfd17ff51b388ac0000000001000000
With the final hash being: 3f857e90be3805b9894f45b5082211f8435bd48d66b22b06a26a4ca37fb679c2
I am sure this has been asked before but my poor search skills have still not found the answer so I am hoping someone could save me a bit of time.
I have now written code to create raw transactions (of the "standard" variety) and one such example is the following:
I want to now be able to "sign" the raw transactions (without using Bitcoin to do so - just doing it with my own code). I have all the source code needed to do this (in terms of the crypto stuff) but what I can't work out is "what is the actual message that is signed"?
(i.e. exactly what binary input do I pass to the ECDSA_do_sign function for each UTXO?)
I have now written code to create raw transactions (of the "standard" variety) and one such example is the following:
Code:
0100000002bad39efeeb23cc53077749d728a048092a767d552109ba35a3ded464a81636960000000000ffffffff8a048092a767d552109ba35a3ded464a8163696bad39efeeb23cc53077749d726400000000ffffffff02e8030000000000001976a914f54a5851e9372b87810a8e60cdd2e7cfd80b6e3188ac400d0300000000001976a914f54a5851e9372b87810a8e60cdd2e7cfd80b6e3188ac00000000
I want to now be able to "sign" the raw transactions (without using Bitcoin to do so - just doing it with my own code). I have all the source code needed to do this (in terms of the crypto stuff) but what I can't work out is "what is the actual message that is signed"?
(i.e. exactly what binary input do I pass to the ECDSA_do_sign function for each UTXO?)
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