actually, it probably was an attack. the 64-bit node is the one that didn't accept the block, and my 32-bit node did. it could be this same signature attack:
https://talk.peercoin.net/t/invalid-checkpoint/3691/17I don't know what to do about it, unless there are enough of us left to want to bother saving it. I could probably figure out how to make that same patch into the AMC code if there's enough interest.
I have some more info on this:
from ns003 (64-bit):
received block f0cc4ed95c7072b6962a
Trying to connect block...
SetBestChain: new best=f0cc4ed95c7072b6962a height=291964 work=393693310144107
0 date=12/20/17 16:08:47
ProcessBlock: ACCEPTED
received block 1928b86bad1213da5a18
Trying to connect block...
trying connection 69.172.201.153:9056 lastseen=75.0hrs
ERROR: FetchInputs() : be93debdd9 prev tx 6cd5e6a343 index entry not found
InvalidChainFound: invalid block=1928b86bad1213da5a18 height=291965 work=39369
33180568620 date=12/20/17 16:14:27
InvalidChainFound: current best=f0cc4ed95c7072b6962a height=291964 work=39369
33101441070 date=12/20/17 16:08:47
ERROR: SetBestChain() : SetBestChainInner failed
ERROR: AcceptBlock() : AddToBlockIndex failed
ERROR: ProcessBlock() : AcceptBlock FAILED
received block 14e4ce12ad6ee099e8c8
Postponing 1 reconnects
REORGANIZE
REORGANIZE: Disconnect 0 blocks; f0cc4ed95c7072b6962a..f0cc4ed95c7072b6962a
REORGANIZE: Connect 1 blocks; f0cc4ed95c7072b6962a..1928b86bad1213da5a18
Trying to connect block...
ERROR: FetchInputs() : be93debdd9 prev tx 6cd5e6a343 index entry not found
ERROR: Reorganize() : ConnectBlock 1928b86bad1213da5a18 failed
from aspire (32-bit), running parser.py, I found 6cd5e6a343 at block 404340,
which equates to block 291702 in debug.log, since the actual block numbers
in blk0001.dat are 112638 higher (counting genesis block as block 0). there
is only one transaction in this block, the coinbase transaction, so the Merkle
root of the block is the same as the transaction hash.
INFO:root:height: 404340
INFO:root:block type: americancoin
INFO:root:block size: 190
INFO:root:block header: b'\x01\x00\x00\x00\xd5z\xa2\x9b`#z\xf4X\xb0Qzo\xd0\x8a\xbb\xe5\xf6\r\xa0\x04\t\x8fpA\xd36\x08w\xf9\x96\n\x04ak\x94\x9d\x03\xb5\x95\xf5\xef\x9a;q\xf9\xe1\xab\x91\x9a\xc2\xd5f\xdcD\x151\xb3\xa7C\xa3\xe6\xd5li\xfb9Z")3\x1d\x00.\x0fk'
INFO:root:block version: 1
INFO:root:previous block hash: b'0a96f9770836d341708f0904a00df6e5bb8ad06f7a51b058f47a23609ba27ad5'
INFO:root:merkle root: b'6cd5e6a343a7b3311544dc66d5c29a91abe1f9713b9aeff595b5039d946b6104'
INFO:root:unix time: 2017-12-20 05:55:53
INFO:root:target_nbits: b'2229331d'
INFO:root:nonce: b'002e0f6b'
INFO:root:transactions (partial): b'\x01\x01\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff\xff\xff\x0e\x04i\xfb9Z\x013\x06/P2SH/\xff\xff\xff\xff\x01\x00\xe4\x0bT\x02\x00\x00\x00#!\x02\xda\xd5Z\x1e87j'
INFO:root:transaction version: 0x00000001 (1)
INFO:root:number of transaction inputs: 1
INFO:root:txin previous txout hash: b'0000000000000000000000000000000000000000000000000000000000000000'
INFO:root:txin previous txout index: 0xffffffff (4294967295)
INFO:root:txin script: b'\x04i\xfb9Z\x013\x06/P2SH/'
INFO:root:txin sequence number: 0xffffffff (4294967295)
INFO:root:number of transaction outputs: 1
INFO:root:txout value: 100.00000000
INFO:root:txout script: b'!\x02\xda\xd5Z\x1e87jUW\xfe\x08\x98\x9b\x86\x1d\xc5\xd7t\xfd\xe1-\x9b\xd1\xb2\xe7_\xb0\xf9J\xb5U\x84\xac'
INFO:root:lock time: b'00000000'
INFO:root:transaction hash: b'6cd5e6a343a7b3311544dc66d5c29a91abe1f9713b9aeff595b5039d946b6104'
INFO:root:transaction count: 1
that same transaction was referenced in block 404603 (291965), as one of the
inputs to the 2nd of 2 transactions (the first, of course, being the coinbase
transaction):
INFO:root:txin previous txout hash: b'6cd5e6a343a7b3311544dc66d5c29a91abe1f9713b9aeff595b5039d946b6104'
INFO:root:txin previous txout index: 0x00000000 (0)
INFO:root:txin script: b'G0D\x02 d\xc1m^\x15\xa9\n\xbd/h\xa8a\xfaI\xd2.\x14\x00\xb4\xcf\xc6|\xfa=\xc4\xd9\xe9,O\xe94\x1f\x02 S\x1c\xa0\xe9#\x8c\xbeq\x17z[x0\x06E\xa0\xefXe\xc3\xb9\x03\t\xb9\x0c\x01\xc8\x88\xf4\x96\xcf7\x01'
INFO:root:txin sequence number: 0xffffffff (4294967295)
this transaction has as its hash the above-referenced be93debdd9:
INFO:root:number of transaction outputs: 2
INFO:root:txout value: 0.01500016
INFO:root:txout script: b'v\xa9\x14^\x99\xe9\xb9\xa2\xe4\x82u\xed\xba\xe8\x9c\x9e7j\xe1\x02&\x92\xea\x88\xac'
INFO:root:txout value: 51300.00000000
INFO:root:txout script: b'v\xa9\x14\xe2B\x8d\xf0u}\xdf\x17o\xe8\xc1c\xf1\xbf\xde\xe5\xd3h%n\x88\xac'
INFO:root:lock time: b'00000000'
INFO:root:transaction hash: b'be93debdd9ca768317221575e832f0cd8d0936b97be8b3bdc309a0b62f1b89c6'
INFO:root:transaction count: 2
so now to figure out why the index entry was not found. perhaps a corrupted blk0001.dat file on the affected machine. but if not, then I've got to dig into the script for that transaction and debug how the 64-bit daemon processes it differently than the 32-bit.
[later...]
there's a difference in the files. the blockchain forked.
$ diff <(head -n2000000 /tmp/aspire.blk0001.xxd) <(head -n2000000 /tmp/ns003.blk0001.xxd) | head
1597237,1597240c1597237,1597240
< 185f340: 4181 d47a e821 b6c4 416a 2909 0462 f600 A..z.!..Aj)..b..
< 185f350: 86cc 6fe2 c5eb 83e2 8a32 e75e a9c4 2054 ..o......2.^.. T
< 185f360: b679 773b e647 bc71 ab52 cdca 511c 001a .yw;.G.q.R..Q...
< 185f370: a71a 0101 0000 0001 0000 0000 0000 0000 ................
---
> 185f340: 4181 d47a e821 0653 86c6 0e24 a358 58cb A..z.!.S...$.XX.
> 185f350: 4143 8a6a 865d 23ec b99f f43c 78f5 4db9 AC.j.]#....<x.M.
> 185f360: 04ed 172c b146 bd71 ab52 cdca 511c 00da ...,.F.q.R..Q...
> 185f370: 9839 0101 0000 0001 0000 0000 0000 0000 .9..............
