Add onion failed; error code 513 #21147

Add onion failed; error code 513

Details mentioned in debug.log:

2021-02-10T20:01:58Z tor: Successfully connected!
2021-02-10T20:01:58Z tor: Connected to Tor version 0.3.2.10
2021-02-10T20:01:58Z tor: Supported authentication method: COOKIE
2021-02-10T20:01:58Z tor: Supported authentication method: HASHEDPASSWORD
2021-02-10T20:01:58Z tor: Supported authentication method: SAFECOOKIE
2021-02-10T20:01:58Z tor: Using SAFECOOKIE authentication, reading cookie authentication from /var/run/tor/control.authcookie
2021-02-10T20:01:58Z tor: SAFECOOKIE authentication challenge successful
2021-02-10T20:01:58Z tor: AUTHCHALLENGE ServerHash fec05d578a7f60d426bc9fbee942102f458f3921db4585c5020d3295b58c56d1 ServerNonce eb57b69b846cfa0984905079b964b0662d71c134cc0afd816cb297d24d37dc10
2021-02-10T20:01:58Z tor: Authentication successful
2021-02-10T20:01:58Z tor: Add onion failed; error code 513
2021-02-10T20:01:58Z Loaded 19221 addresses from peers.dat  209ms
2021-02-10T20:01:58Z Loaded 2 addresses from "anchors.dat"
2021-02-10T20:01:58Z 2 block-relay-only anchors will be tried for connections.
2021-02-10T20:01:58Z init message: Starting network threads...
2021-02-10T20:01:58Z init message: Done loading
2021-02-10T20:01:58Z msghand thread start
2021-02-10T20:01:58Z opencon thread start
2021-02-10T20:01:58Z addcon thread start
2021-02-10T20:01:58Z dnsseed thread start

Not sure why it connects to Tor version 0.3.2.10 because I have a recent version on this machine:

prayank@ubuntu:~/.bitcoin$ tor --version
Tor version 0.4.4.6.

What can be the possible reason for this error?

bitcoin.conf file:

testnet=1
listen=1
torcontrol=127.0.0.1:9051
onlynet=onion
debug=tor
prune=555

/etc/tor/torrc

ControlPort 9051
CookieAuthentication 1
CookieAuthFileGroupReadable 1
HashedControlPassword 16:07XXXXXXXXXXXXXXXXXXXXXXXXXXXX$

The issue is with Tor version being used imo because similar setup on new machine with Tor 0.4.2.7 works fine

2021-02-11T17:21:56Z addcon thread start
2021-02-11T17:21:56Z net thread start
2021-02-11T17:21:56Z tor: ADD_ONION successful
2021-02-11T17:21:56Z tor: Got service ID omy7kj7zwvfg5luayideh73uqb2latkoyyy5h65y4atv3fymnlxlzwqd, advertising service omy7kj7zwvfg5luayideh73uqb2latkoyyy5h65y4atv3fymnlxlzwqd.onion:18333
2021-02-11T17:21:56Z tor: Cached service private key to /home/satoshi/.bitcoin/testnet3/onion_v3_private_key
2021-02-11T17:21:56Z AddLocal(omy7kj7zwvfg5luayideh73uqb2latkoyyy5h65y4atv3fymnlxlzwqd.onion:18333,4)

One reason why torcontrol may return 513 is if the target is unreachable.

Target ip is set to 127.0.0.1

This assumes that the tor proxy is running on the same machine. That might not be the case in a LAN setup. A better approach would be to use the bind address value if specified. If not, then fallback on 127.0.0.1

I gave my idea a shot and it didn't fix the problem. I did tweak a little bit the logs to have more info. I printed the torcontrol reply first line instead of the error code. Here is what I got:

2021-08-29T14:19:06Z tor: Add onion cmd: ADD_ONION NEW:RSA1024 Port=9999,192.168.1.179:9999
2021-08-29T14:19:06Z tor: Add onion failed; error Invalid key type

I found something interesting. With tor 0.4.6.7, the algorithm RSA1024 is not accepted anymore. The only choices are:

BEST or ED25519-V3

fixed by: https://github.com/bitcoin/bitcoin/pull/19954/commits/dcf0cb477699d11afd0ff37c8bfb2b1b4f7f1ee5