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fix: names are case insensitive

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This commit is contained in:
Richard Schneider
2018-09-13 12:44:19 +12:00
parent 2e0219a819
commit 8cc12972d2
1 changed files with 11 additions and 16 deletions
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27
discovery/mdns.md
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@@ -14,12 +14,11 @@ As responses come in, the peer adds the other peers information into is local da
`service-name` is the DNS-SD service name for all peers. It is defined as `_p2p._udp.local`.
`host-name` is the name of the peer. It is derived from the peer's ID and `p2p.local`, for example
`Qmid.p2p.local`.
`host-name` is the fully qualified name of the peer. It is derived from the peer's name and `p2p.local`.
`peer-id` is the ID of the peer. It normally is the base-58 enconding of the hash of the peer's public key.
`peer-name` is the case-insenstive ID of the peer and less than 64 characters. It is normally is the base-32 encoding of peer's ID.
`port` is a port that the peer listens on. Normally 4001.
Note that all names are case insensitive.
## Peer Discovery
@@ -28,22 +27,22 @@ As responses come in, the peer adds the other peers information into is local da
To find all peers, a DNS message is sent with the question `_p2p._udp.local PTR`.
Peers will then start responding with their details.
Note that a peer must respond to it's own query. Thus allows other peers to passively discover it.
Note that a peer must respond to it's own query. This allows other peers to passively discover it.
### Response
On receipt of a `find all peers` query, a peer sends a DNS response message (QR = 1) that contains
the **answer**
<service-name> PTR <peer-id>.<service-name>
<service-name> PTR <peer-name>.<service-name>
The **additional records** of the response contain the peer's discovery details
<peer-id>.<service-name> TXT "dnsaddr=..."
<peer-name>.<service-name> TXT "dnsaddr=..."
The TXT record contains the multiaddresses that the peer is listening on. Each multiaddress
is a TXT attribute with the form `dnsaddr=/ip4/.../tcp/.../p2p/QmId`. Multiple `dnsaddr` attributes
are expected.
is a TXT attribute with the form `dnsaddr=.../p2p/QmId`. Multiple `dnsaddr` attributes
and/or TXT records are allowed.
## DNS Service Discovery
@@ -63,26 +62,22 @@ A peer responds with the answer
On receipt of a `find all peers` query, the following **additional records** should be included
<peer-id>.<service-name> SRV ... <port> <host-name>
<peer-name>.<service-name> SRV ... <host-name>
<host-name> A <ipv4 address>
<host-name> AAAA <ipv6 address>
If a peer is listening on multiple ports, it should respond with multiple `SRV` records for each
port it is listening on.
### Gotchas
Many existing tools ignore the Additional Records and always send individual queries for the
peer's discovery details. To accomodate this, a peer should respond to the following queries:
- `<peer-id>.<service-name> SRV`
- `<peer-id>.<service-name> TXT`
- `<peer-name>.<service-name> SRV`
- `<peer-name>.<service-name> TXT`
- `<host-name> A`
- `<host-name> AAAA`
## Issues
- like urls, dns names are case insensitive. A `peer-id` is base58btc encoded and is case sensitive.
- MDNS requires link local addresses. Loopback and "nat busting" addresses should not sent and must
be ignored on receipt?