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dns/dns.bend fails

raw source on the hub · import 0x575208cf32f35c10d64d398769aef1bc/dns/dns.bend as Dns

2 imports
import Base
import ../wire.bend as Wire

Types

type Cur source · line 7 · raw

Data

type RR source · line 10 · raw

Data

type Try source · line 311 · raw

Data

One attempt's outcome: try again, or this answer (None: no address).

Definitions

def u8 source · line 15 · raw

@s:String -> Maybe<&2, Cur>

def u16.lo source · line 22 · raw

@hi:U32 -> @m:Maybe<&2, Cur> -> Maybe<&2, Cur>

def u16.go source · line 29 · raw

@m:Maybe<&2, Cur> -> Maybe<&2, Cur>

def u16 source · line 36 · raw

@s:String -> Maybe<&2, Cur>

def skip.if source · line 39 · raw

@+s:String -> @+n:Nat -> @short:Bool -> Maybe<&2, String>

def skip source · line 46 · raw

@+s:String -> @+n:Nat -> Maybe<&2, String>

def then source · line 49 · raw

@m:Maybe<&2, String> -> @n:Nat -> Maybe<&2, String>

def push16 source · line 56 · raw

@+n:U32 -> @acc:String -> String

def label.ok source · line 62 · raw

@+l:String -> Bool

def label.ascii source · line 66 · raw

@s:String -> Bool

def labels.ok source · line 73 · raw

@xs:List<&2, String> -> Bool

def labels.put source · line 80 · raw

@xs:List<&2, String> -> @acc:String -> String

def query.if source · line 87 · raw

@+id:U32 -> @xs:List<&2, String> -> @ok:Bool -> Maybe<&2, String>

def query.labels source · line 95 · raw

@+id:U32 -> @+xs:List<&2, String> -> Maybe<&2, String>

def strip_dot.if source · line 98 · raw

@+s:String -> @dot:Bool -> String

def strip_dot source · line 105 · raw

@+s:String -> String

def query source · line 109 · raw

@id:U32 -> @name:String -> Maybe<&2, String>

RFC 1035 §4.1: a standard query for the A record of name.

def name.skip source · line 116 · raw

@fuel:Nat -> @s:String -> Maybe<&2, String>

§4.1.4: a name is labels ending in a zero octet, or a two-octet pointer.

def name.then source · line 127 · raw

@m:Maybe<&2, String> -> @n:Nat -> Maybe<&2, String>

def dotted source · line 134 · raw

@s:String -> String

def rr.f source · line 145 · raw

@+r:String -> @+len:U32 -> @a:Bool -> RR

def rr.data source · line 152 · raw

@+r:String -> @+len:U32 -> @a:Bool -> @short:Bool -> RR

def rr.e source · line 159 · raw

@+ty:U32 -> @+cl:U32 -> @m:Maybe<&2, Cur> -> RR

def rr.d source · line 166 · raw

@ty:U32 -> @cl:U32 -> @m:Maybe<&2, String> -> RR

def rr.c source · line 173 · raw

@ty:U32 -> @m:Maybe<&2, Cur> -> RR

def rr.b source · line 180 · raw

@m:Maybe<&2, Cur> -> RR

def rr.a source · line 187 · raw

@m:Maybe<&2, String> -> RR

def rr source · line 195 · raw

@+s:String -> RR

§4.1.3: NAME, TYPE, CLASS, TTL, RDLENGTH, RDATA.

def answers.scan source · line 199 · raw

@fuel:Nat -> @r:RR -> Maybe<&2, String>

fuel = records left. The first A record wins; CNAMEs before it are skipped.

def questions source · line 212 · raw

@fuel:Nat -> @m:Maybe<&2, String> -> Maybe<&2, String>

def body.go source · line 219 · raw

@an:U32 -> @m:Maybe<&2, String> -> Maybe<&2, String>

def body.an source · line 226 · raw

@qd:U32 -> @m:Maybe<&2, Cur> -> Maybe<&2, String>

def body.qd source · line 233 · raw

@m:Maybe<&2, Cur> -> Maybe<&2, String>

def flags.ok source · line 241 · raw

@+f:U32 -> Bool

§4.1.1: QR set, opcode QUERY, not truncated, RCODE 0.

def head.flags.if source · line 244 · raw

@r:String -> @ok:Bool -> Maybe<&2, String>

def head.flags source · line 251 · raw

@m:Maybe<&2, Cur> -> Maybe<&2, String>

def head.id.if source · line 258 · raw

@r:String -> @ok:Bool -> Maybe<&2, String>

def head.id source · line 265 · raw

@id:U32 -> @m:Maybe<&2, Cur> -> Maybe<&2, String>

def answer source · line 273 · raw

@id:U32 -> @msg:String -> Maybe<&2, String>

The IPv4 address the response gives for the query with this id.

def nameserver.line source · line 279 · raw

@+line:String -> @rest:Maybe<&2, String> -> Maybe<&2, String>

def nameserver.go source · line 282 · raw

@xs:List<&2, String> -> Maybe<&2, String>

def nameserver source · line 290 · raw

@conf:String -> Maybe<&2, String>

The first nameserver line of a resolv.conf.

def none source · line 296 · raw

IO(Maybe<&2, String>)

def ipv4.go source · line 299 · raw

@s:String -> Bool

def ipv4 source · line 307 · raw

@+s:String -> Bool

Digits and dots; TCP.connect rejects anything else that is not an address.

def try.pure source · line 315 · raw

@s:Socket -> @t:Try -> IO(Pair(Socket, Try))

def try.from source · line 319 · raw

@s:Socket -> @+ns:String -> @id:U32 -> @hpd:Pair(String, Pair(U32, String)) -> IO(Pair(Socket, Try))

A datagram from anyone but the nameserver's port 53 is ignored (retried).

def try.back source · line 323 · raw

@ns:String -> @id:U32 -> @m:Pair(Socket, Result<&1, &1, Pair(U32, String), Pair(String, Pair(U32, String))>) -> IO(Pair(Socket, Try))

def try.sent source · line 332 · raw

@ns:String -> @id:U32 -> @m:Pair(Socket, Result<&1, &1, Pair(U32, String), Unit>) -> IO(Pair(Socket, Try))

§4.2.1 and resolv.conf defaults: 5 s per attempt.

def try.once source · line 342 · raw

@s:Socket -> @+ns:String -> @id:U32 -> @q:String -> IO(Pair(Socket, Try))

def try.close source · line 347 · raw

@s:Socket -> @r:Maybe<&2, String> -> IO(Maybe<&2, String>)

def tries.end source · line 352 · raw

@st:Pair(Socket, Try) -> IO(Maybe<&2, String>)

def tries source · line 361 · raw

@fuel:Nat -> @+ns:String -> @+id:U32 -> @+q:String -> @st:Pair(Socket, Try) -> IO(Maybe<&2, String>)

fuel: attempts left (resolv.conf's default is 2).

def resolve.sock source · line 375 · raw

@ns:String -> @id:U32 -> @q:String -> @r:Result<&1, &1, Pair(U32, String), Socket> -> IO(Maybe<&2, String>)

def resolve.q source · line 382 · raw

@ns:String -> @id:U32 -> @q:Maybe<&2, String> -> IO(Maybe<&2, String>)

def resolve.id source · line 392 · raw

@name:String -> @ns:String -> @r:Result<&1, &1, Pair(U32, String), U32> -> IO(Maybe<&2, String>)

§7.3: a random id makes forged answers harder to land.

def resolve.ns source · line 400 · raw

@name:String -> @ns:Maybe<&2, String> -> IO(Maybe<&2, String>)

def conf.text source · line 409 · raw

@r:Result<&1, &1, Pair(U32, String), String> -> String

def resolve.read source · line 416 · raw

@name:String -> @m:Pair(File, Result<&1, &1, Pair(U32, String), String>) -> IO(Maybe<&2, String>)

def resolve.conf source · line 422 · raw

@name:String -> @r:Result<&1, &1, Pair(U32, String), File> -> IO(Maybe<&2, String>)

def resolve.dns source · line 431 · raw

@name:String -> IO(Maybe<&2, String>)

def resolve source · line 438 · raw

@+host:String -> IO(Maybe<&2, String>)

An IPv4 address for host: literals as is, localhost (RFC 6761), else DNS. ponytail: no /etc/hosts, no AAAA, no TCP retry on TC