If both options "onion" and "proxy" are unset, no outbound Onion connections should be made #22647

bitcoind 22.0rc2

Having the following bitcoin.conf

upnp=0
debug=i2p
shrinkdebugfile=1
onlynet=i2p
listen=1
timeout=20000
server=1
maxtxfee=0.001
i2psam=127.0.0.1:7656
addnode=72l3ucjkuscrbiiepoehuwqgknyzgo7zuix5ty4puwrkyhtmnsga.b32.i2p:0
addnode=c4gfnttsuwqomiygupdqqqyy5y5emnk5c73hrfvatri67prd7vyq.b32.i2p:0
addnode=gehtac45oaghz54ypyopim64mql7oad2bqclla74l6tfeolzmodq.b32.i2p:0
addnode=h3r6bkn46qxftwja53pxiykntegfyfjqtnzbm6iv6r5mungmqgmq.b32.i2p:0
addnode=hnbbyjpxx54623l555sta7pocy3se4sdgmuebi5k6reesz5rjp6q.b32.i2p:0
addnode=pjs7or2ctvteeo5tu4bwyrtydeuhqhvdprtujn4daxr75jpebjxa.b32.i2p:0
addnode=wwbw7nqr3ahkqv62cuqfwgtneekvvpnuc4i4f6yo7tpoqjswvcwa.b32.i2p:0
addnode=zsxwyo6qcn3chqzwxnseusqgsnuw3maqnztkiypyfxtya4snkoka.b32.i2p:0

Makes bitcoind connect outgoing to Onion network. bitcoind --help says for option onlynet: "if it is used with non-onion networks and the -onion or -proxy option is set, then outbound onion connections will still be made; use -noonion or -onion=0 to disable outbound onion connections in this case."

But as you can see, neither onion nor proxy is set. proxy defaults to "disabled" (=0 ?), and onion defaults to value of proxy, so if proxy is unset=disabled, onion should be disabled(=0), too. There should be no need for setting onion=0 in this case.

The above sentence would be clearer like so: "use -noonion or -onion=0 to disable outbound onion connections if proxy is set"

Expected behavior

No outgoing connections to Onion network, only to I2P network.

Actual behavior

Outgoing connections to both Onion and I2P network.

To reproduce

Use above bitcoin.conf.

System information

Debian Buster amd_64

Opened a draft at #22648 and will look into addressing your comments.

This looks like a bug or at least some serious violation of the Principle of least astonishment.

I wonder how did bitcoind find the Tor socks5 proxy if none of -proxy or -onion is specified? Can you post the full debug.log and the output of bitcoin-cli getnetworkinfo. I could not reproduce it.

debug.log. The last line was the first outbound connection, which was of type Onion.

2021-08-06T13:27:10Z Bitcoin Core version v22.0.0-g873fbc745d037ad43570f81e58334c397bc95477 (release build)
2021-08-06T13:27:10Z Qt 5.12.11 (static), plugin=xcb (static)
2021-08-06T13:27:10Z Static plugins:
2021-08-06T13:27:10Z  QXcbIntegrationPlugin, version 330752
2021-08-06T13:27:10Z Style: fusion / QFusionStyle
2021-08-06T13:27:10Z System: Debian GNU/Linux 10 (buster), x86_64-little_endian-lp64
2021-08-06T13:27:10Z Screen: Virtual-1 1600x900, pixel ratio=1.0
2021-08-06T13:27:10Z Assuming ancestors of block 00000000000000000008a89e854d57e5667df88f1cdef6fde2fbca1de5b639ad have valid signatures.
2021-08-06T13:27:10Z Setting nMinimumChainWork=00000000000000000000000000000000000000001fa4663bbbe19f82de910280
2021-08-06T13:27:10Z Using the 'sse4(1way),sse41(4way)' SHA256 implementation
2021-08-06T13:27:10Z Using RdSeed as additional entropy source
2021-08-06T13:27:10Z Using RdRand as an additional entropy source
2021-08-06T13:27:10Z Default data directory /home/user/.bitcoin
2021-08-06T13:27:10Z Using data directory /home/user/.bitcoin
2021-08-06T13:27:10Z Config file: /home/user/.bitcoin/bitcoin.conf
2021-08-06T13:27:10Z Config file arg: addnode="72l3ucjkuscrbiiepoehuwqgknyzgo7zuix5ty4puwrkyhtmnsga.b32.i2p:0"
2021-08-06T13:27:10Z Config file arg: addnode="c4gfnttsuwqomiygupdqqqyy5y5emnk5c73hrfvatri67prd7vyq.b32.i2p:0"
2021-08-06T13:27:10Z Config file arg: addnode="gehtac45oaghz54ypyopim64mql7oad2bqclla74l6tfeolzmodq.b32.i2p:0"
2021-08-06T13:27:10Z Config file arg: addnode="h3r6bkn46qxftwja53pxiykntegfyfjqtnzbm6iv6r5mungmqgmq.b32.i2p:0"
2021-08-06T13:27:10Z Config file arg: addnode="hnbbyjpxx54623l555sta7pocy3se4sdgmuebi5k6reesz5rjp6q.b32.i2p:0"
2021-08-06T13:27:10Z Config file arg: addnode="pjs7or2ctvteeo5tu4bwyrtydeuhqhvdprtujn4daxr75jpebjxa.b32.i2p:0"
2021-08-06T13:27:10Z Config file arg: addnode="wwbw7nqr3ahkqv62cuqfwgtneekvvpnuc4i4f6yo7tpoqjswvcwa.b32.i2p:0"
2021-08-06T13:27:10Z Config file arg: addnode="zsxwyo6qcn3chqzwxnseusqgsnuw3maqnztkiypyfxtya4snkoka.b32.i2p:0"
2021-08-06T13:27:10Z Config file arg: debug="i2p"
2021-08-06T13:27:10Z Config file arg: i2psam="127.0.0.1:7656"
2021-08-06T13:27:10Z Config file arg: listen="1"
2021-08-06T13:27:10Z Config file arg: maxtxfee="0.001"
2021-08-06T13:27:10Z Config file arg: onlynet="i2p"
2021-08-06T13:27:10Z Config file arg: server="1"
2021-08-06T13:27:10Z Config file arg: shrinkdebugfile="1"
2021-08-06T13:27:10Z Config file arg: timeout="20000"
2021-08-06T13:27:10Z Config file arg: upnp="0"
2021-08-06T13:27:10Z Using at most 125 automatic connections (1024 file descriptors available)
2021-08-06T13:27:10Z Using 16 MiB out of 32/2 requested for signature cache, able to store 524288 elements
2021-08-06T13:27:10Z Using 16 MiB out of 32/2 requested for script execution cache, able to store 524288 elements
2021-08-06T13:27:10Z Script verification uses 1 additional threads
2021-08-06T13:27:10Z scheduler thread start
2021-08-06T13:27:10Z HTTP: creating work queue of depth 16
2021-08-06T13:27:10Z Using random cookie authentication.
2021-08-06T13:27:10Z Generated RPC authentication cookie /home/user/.bitcoin/.cookie
2021-08-06T13:27:10Z HTTP: starting 4 worker threads
2021-08-06T13:27:10Z Using wallet directory /home/user/.bitcoin
2021-08-06T13:27:10Z init message: Überprüfe Wallet(s)...
2021-08-06T13:27:10Z Using BerkeleyDB version Berkeley DB 4.8.30: (April  9, 2010)
2021-08-06T13:27:10Z Using wallet /home/user/.bitcoin/wallet.dat
2021-08-06T13:27:10Z BerkeleyEnvironment::Open: LogDir=/home/user/.bitcoin/database ErrorFile=/home/user/.bitcoin/db.log
2021-08-06T13:27:10Z init message: Lade Bannliste…
2021-08-06T13:27:10Z SetNetworkActive: true
2021-08-06T13:27:10Z Using /16 prefix for IP bucketing
2021-08-06T13:27:10Z Cache configuration:
2021-08-06T13:27:10Z * Using 2.0 MiB for block index database
2021-08-06T13:27:10Z * Using 8.0 MiB for chain state database
2021-08-06T13:27:10Z * Using 290.0 MiB for in-memory UTXO set (plus up to 286.1 MiB of unused mempool space)
2021-08-06T13:27:10Z init message: Lade Block-Index...
2021-08-06T13:27:10Z Switching active chainstate to Chainstate [ibd] @ height -1 (null)
2021-08-06T13:27:10Z Opening LevelDB in /home/user/.bitcoin/blocks/index
2021-08-06T13:27:10Z Opened LevelDB successfully
2021-08-06T13:27:10Z Using obfuscation key for /home/user/.bitcoin/blocks/index: 0000000000000000
2021-08-06T13:27:16Z LoadBlockIndexDB: last block file = 2679
2021-08-06T13:27:16Z LoadBlockIndexDB: last block file info: CBlockFileInfo(blocks=126, size=115009652, heights=694332...694480, time=2021-08-05...2021-08-06)
2021-08-06T13:27:16Z Checking all blk files are present...
2021-08-06T13:27:16Z Opening LevelDB in /home/user/.bitcoin/chainstate
2021-08-06T13:27:17Z Opened LevelDB successfully
2021-08-06T13:27:17Z Using obfuscation key for /home/user/.bitcoin/chainstate: 0000000000000000
2021-08-06T13:27:17Z Loaded best chain: hashBestChain=00000000000000000003bfbfaf2b79a93047a1d82b00ca70a727135956e3f11b height=694480 date=2021-08-06T13:21:10Z progress=0.999999
2021-08-06T13:27:17Z init message: Überprüfe Blöcke...
2021-08-06T13:27:17Z Verifying last 6 blocks at level 3
2021-08-06T13:27:17Z [0%]...[16%]...[33%]...[50%]...[66%]...[83%]...[99%]...[DONE].
2021-08-06T13:27:18Z No coin database inconsistencies in last 6 blocks (6887 transactions)
2021-08-06T13:27:18Z  block index            7426ms
2021-08-06T13:27:18Z init message: Lade Wallet...
2021-08-06T13:27:18Z BerkeleyEnvironment::Open: LogDir=/home/user/.bitcoin/database ErrorFile=/home/user/.bitcoin/db.log
2021-08-06T13:27:18Z [default wallet] Wallet File Version = 169900
2021-08-06T13:27:18Z [default wallet] Keys: 0 plaintext, 4012 encrypted, 4012 w/ metadata, 4012 total. Unknown wallet records: 0
2021-08-06T13:27:18Z [default wallet] Wallet completed loading in              53ms
2021-08-06T13:27:18Z [default wallet] setKeyPool.size() = 1999
2021-08-06T13:27:18Z [default wallet] mapWallet.size() = 9
2021-08-06T13:27:18Z [default wallet] m_address_book.size() = 11
2021-08-06T13:27:18Z block tree size = 694695
2021-08-06T13:27:18Z nBestHeight = 694480
2021-08-06T13:27:18Z loadblk thread start
2021-08-06T13:27:18Z torcontrol thread start
2021-08-06T13:27:18Z Bound to 127.0.0.1:8334
2021-08-06T13:27:18Z Bound to [::]:8333
2021-08-06T13:27:18Z Bound to 0.0.0.0:8333
2021-08-06T13:27:18Z init message: Lade P2P-Adressen...
2021-08-06T13:27:18Z Leaving InitialBlockDownload (latching to false)
2021-08-06T13:27:18Z tor: Got service ID ........................................................, advertising service .........................................................onion:8333
2021-08-06T13:27:18Z AddLocal(.........................................................onion:8333,4)
2021-08-06T13:27:18Z Loaded 57329 addresses from peers.dat  343ms
2021-08-06T13:27:18Z Loaded 0 addresses from "anchors.dat"
2021-08-06T13:27:18Z 0 block-relay-only anchors will be tried for connections.
2021-08-06T13:27:18Z init message: Starte Netzwerk-Threads...
2021-08-06T13:27:18Z init message: Laden abgeschlossen
2021-08-06T13:27:18Z i2paccept thread start
2021-08-06T13:27:18Z I2P: Creating SAM session with 127.0.0.1:7656
2021-08-06T13:27:18Z opencon thread start
2021-08-06T13:27:18Z dnsseed thread start
2021-08-06T13:27:18Z Waiting 300 seconds before querying DNS seeds.
2021-08-06T13:27:18Z addcon thread start
2021-08-06T13:27:18Z net thread start
2021-08-06T13:27:18Z msghand thread start
2021-08-06T13:27:18Z GUI: Platform customization: "other"
2021-08-06T13:27:19Z Imported mempool transactions from disk: 1080 succeeded, 0 failed, 0 expired, 0 already there, 0 waiting for initial broadcast
2021-08-06T13:27:19Z loadblk thread exit
2021-08-06T13:27:21Z New outbound peer connected: version: 70016, blocks=694480, peer=0 (outbound-full-relay)

Output of bitcoin-cli getnetworkinfo

{
  "version": 220000,
  "subversion": "/Satoshi:22.0.0/",
  "protocolversion": 70016,
  "localservices": "0000000000000409",
  "localservicesnames": [
    "NETWORK",
    "WITNESS",
    "NETWORK_LIMITED"
  ],
  "localrelay": true,
  "timeoffset": -3,
  "networkactive": true,
  "connections": 15,
  "connections_in": 0,
  "connections_out": 15,
  "networks": [
    {
      "name": "ipv4",
      "limited": true,
      "reachable": false,
      "proxy": "",
      "proxy_randomize_credentials": false
    },
    {
      "name": "ipv6",
      "limited": true,
      "reachable": false,
      "proxy": "",
      "proxy_randomize_credentials": false
    },
    {
      "name": "onion",
      "limited": false,
      "reachable": true,
      "proxy": "127.0.0.1:9050",
      "proxy_randomize_credentials": true
    },
    {
      "name": "i2p",
      "limited": false,
      "reachable": true,
      "proxy": "127.0.0.1:7656",
      "proxy_randomize_credentials": false
    }
  ],
  "relayfee": 0.00001000,
  "incrementalfee": 0.00001000,
  "localaddresses": [
    {
      "address": "....................................onion",
      "port": 8333,
      "score": 4
    },
    {
      "address": ".....................................b32.i2p",
      "port": 0,
      "score": 4
    }
  ],
  "warnings": ""
}

I've reproduced the issue with the 22.0rc2 binary (debian), the above config, i2pd 2.38.0 and tor 0.4.6 on mainnet.

  "networks": [
    {
      "name": "ipv4",
      "limited": true,
      "reachable": false,
      "proxy": "",
      "proxy_randomize_credentials": false
    },
    {
      "name": "ipv6",
      "limited": true,
      "reachable": false,
      "proxy": "",
      "proxy_randomize_credentials": false
    },
    {
      "name": "onion",
      "limited": false,
      "reachable": true,
      "proxy": "127.0.0.1:9050",
      "proxy_randomize_credentials": true
    },
    {
      "name": "i2p",
      "limited": false,
      "reachable": true,
      "proxy": "127.0.0.1:7656",
      "proxy_randomize_credentials": false
    }
  ],
  "relayfee": 0.00001000,
  "incrementalfee": 0.00001000,
  "localaddresses": [
    {
      "address": "xyz.onion",
      "port": 8333,
      "score": 4
    },
    {
      "address": "aw4zvb3rab7tbtfip2q2fre5eahgvthzu5hhq5rpd6llvgkvlyta.b32.i2p",
      "port": 0,
      "score": 4
    }
  ],

With added debug=tor there are those additional log lines:

2021-08-06T13:49:46Z Leaving InitialBlockDownload (latching to false)
2021-08-06T13:49:46Z torcontrol thread start
2021-08-06T13:49:46Z tor: Reading cached private key from /home/user/.bitcoin/onion_v3_private_key
2021-08-06T13:49:46Z tor: Successfully connected!
2021-08-06T13:49:46Z tor: Connected to Tor version 0.3.5.15
2021-08-06T13:49:46Z tor: Supported authentication method: COOKIE
2021-08-06T13:49:46Z tor: Supported authentication method: HASHEDPASSWORD
2021-08-06T13:49:46Z tor: Supported authentication method: SAFECOOKIE
2021-08-06T13:49:46Z tor: Using SAFECOOKIE authentication, reading cookie authentication from /run/tor/control.authcookie
2021-08-06T13:49:46Z tor: SAFECOOKIE authentication challenge successful
2021-08-06T13:49:46Z tor: AUTHCHALLENGE ServerHash ........................... ServerNonce ...............................
2021-08-06T13:49:46Z tor: Authentication successful
2021-08-06T13:49:46Z tor: ADD_ONION successful
2021-08-06T13:49:46Z tor: Got service ID ..................., advertising service ....................................onion:8333
2021-08-06T13:49:46Z tor: Cached service private key to /home/user/.bitcoin/onion_v3_private_key
2021-08-06T13:49:46Z AddLocal(...............................onion:8333,4)

Current solution is to add onion=0: this blocks outbound onion connections, I2P outbound connections only.

  "networks": [
    {
      "name": "ipv4",
      "limited": true,
      "reachable": false,
      "proxy": "",
      "proxy_randomize_credentials": false
    },
    {
      "name": "ipv6",
      "limited": true,
      "reachable": false,
      "proxy": "",
      "proxy_randomize_credentials": false
    },
    {
      "name": "onion",
      "limited": true,
      "reachable": false,
      "proxy": "",
      "proxy_randomize_credentials": false
    },
    {
      "name": "i2p",
      "limited": false,
      "reachable": true,
      "proxy": "127.0.0.1:7656",
      "proxy_randomize_credentials": false
    }
  ],
  "relayfee": 0.00001000,
  "incrementalfee": 0.00001000,
  "localaddresses": [
    {
      "address": "aw4zvb3rab7tbtfip2q2fre5eahgvthzu5hhq5rpd6llvgkvlyta.b32.i2p",
      "port": 0,
      "score": 4
    }
  ],
  "warnings": ""

Thanks for the debug info!

I wonder how did bitcoind find the Tor socks5 proxy if none of -proxy or -onion is specified?

It just defaults to 127.0.0.1:9050, disrespecting -onlynet:

https://github.com/bitcoin/bitcoin/blob/d67330d11245b11fbdd5e2dd5343ee451186931e/src/torcontrol.cpp#L378-L383

Fixed in https://github.com/bitcoin/bitcoin/pull/22651

Current solution is to add onion=0: this blocks outbound onion connections, I2P outbound connections only.

Do you really in fact get I2P outbound connections with onion=0 and onlynet=i2p ? I did not on a 3h test, see my addition to comment in #22634 (comment)

Edit: I2P only now works for me. Maybe it was a problem of too few nodes or bootstrap issue before. Now I have 10 outbound and even one inbound I2P connection right after startup. I could now also remove the I2P addnode lines from bitcoin.conf, and get I2P connections after restart, I guess the I2P peers are used now from the peer cache.

Yes.

Also, i2pd 2.23.0 (an old version currently still shipped with Debian stable), while a bit funky at first, worked for me across more than a dozen restarts and configurations today to test your reports. I'm running a production node with it now to test it over more time.

Also:

I see many log lines Error connecting to xxx.b32.i2p:0: Unexpected reply to "NAMING LOOKUP NAME=xxx.b32.i2p": "NAMING REPLY RESULT=INVALID_KEY NAME=xxx.b32.i2p"

With i2pd 2.23, this is one of the errors when a peer isn't online. It's normal when some of the addnode peers in your conf file aren't up.

Are there possible tests that could be added to catch errors like this?

Edit: I have now seen the discussion on 22651, sorry!

@jonatak On a second I2P-only test, I get now I2P connections, so pure I2P now works for me too, very nice.