awl/pkg/query/query.go
Sam Therapy e782c9cb23
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feat: change import URL
Signed-off-by: Sam Therapy <sam@samtherapy.net>
2023-02-17 19:18:58 +01:00

145 lines
3.3 KiB
Go

// SPDX-License-Identifier: BSD-3-Clause
package query
import (
"fmt"
"strconv"
"dns.froth.zone/awl/pkg/resolvers"
"dns.froth.zone/awl/pkg/util"
"github.com/dchest/uniuri"
"github.com/miekg/dns"
)
// CreateQuery creates a DNS query from the options given.
// It sets query flags and EDNS flags from the respective options.
func CreateQuery(opts *util.Options) (util.Response, error) {
req := new(dns.Msg)
req.SetQuestion(opts.Request.Name, opts.Request.Type)
req.Question[0].Qclass = opts.Request.Class
// Set standard flags
req.MsgHdr.Response = opts.QR
req.MsgHdr.Authoritative = opts.AA
req.MsgHdr.Truncated = opts.TC
req.MsgHdr.RecursionDesired = opts.RD
req.MsgHdr.RecursionAvailable = opts.RA
req.MsgHdr.Zero = opts.Z
req.MsgHdr.AuthenticatedData = opts.AD
req.MsgHdr.CheckingDisabled = opts.CD
// EDNS time :)
if opts.EDNS.EnableEDNS {
edns := new(dns.OPT)
edns.Hdr.Name = "."
edns.Hdr.Rrtype = dns.TypeOPT
edns.SetVersion(opts.EDNS.Version)
if opts.EDNS.Cookie {
cookie := new(dns.EDNS0_COOKIE)
cookie.Code = dns.EDNS0COOKIE
cookie.Cookie = uniuri.NewLenChars(16, []byte("1234567890abcdef"))
edns.Option = append(edns.Option, cookie)
opts.Logger.Info("Setting EDNS cookie to", cookie.Cookie)
}
if opts.EDNS.Expire {
edns.Option = append(edns.Option, new(dns.EDNS0_EXPIRE))
opts.Logger.Info("Setting EDNS Expire option")
}
if opts.EDNS.KeepOpen {
edns.Option = append(edns.Option, new(dns.EDNS0_TCP_KEEPALIVE))
opts.Logger.Info("Setting EDNS TCP Keepalive option")
}
if opts.EDNS.Nsid {
edns.Option = append(edns.Option, new(dns.EDNS0_NSID))
opts.Logger.Info("Setting EDNS NSID option")
}
if opts.EDNS.Padding {
edns.Option = append(edns.Option, new(dns.EDNS0_PADDING))
opts.Logger.Info("Setting EDNS padding")
}
edns.SetUDPSize(opts.EDNS.BufSize)
opts.Logger.Info("EDNS UDP buffer set to", opts.EDNS.BufSize)
edns.SetZ(opts.EDNS.ZFlag)
opts.Logger.Info("EDNS Z flag set to", opts.EDNS.ZFlag)
if opts.EDNS.DNSSEC {
edns.SetDo()
opts.Logger.Info("EDNS DNSSEC OK set")
}
if opts.EDNS.Subnet.Address != nil {
edns.Option = append(edns.Option, &opts.EDNS.Subnet)
}
req.Extra = append(req.Extra, edns)
} else if opts.EDNS.DNSSEC {
req.SetEdns0(1232, true)
opts.Logger.Warn("DNSSEC implies EDNS, EDNS enabled")
opts.Logger.Info("DNSSEC enabled, UDP buffer set to 1232")
}
opts.Logger.Debug(req)
if !opts.Short {
if opts.Display.ShowQuery {
opts.Logger.Info("Printing constructed query")
var (
str string
err error
)
if opts.JSON || opts.XML || opts.YAML {
str, err = PrintSpecial(util.Response{DNS: req}, opts)
if err != nil {
return util.Response{}, err
}
} else {
temp := opts.Display.Statistics
opts.Display.Statistics = false
str, err = ToString(
util.Response{
DNS: req,
RTT: 0,
}, opts)
if err != nil {
return util.Response{}, err
}
opts.Display.Statistics = temp
str += "\n;; QUERY SIZE: " + strconv.Itoa(req.Len()) + "\n"
}
fmt.Println(str)
opts.Display.ShowQuery = false
}
}
resolver, err := resolvers.LoadResolver(opts)
if err != nil {
return util.Response{}, fmt.Errorf("unable to load resolvers: %w", err)
}
opts.Logger.Info("Query successfully loaded")
//nolint:wrapcheck // Error wrapping not needed here
return resolver.LookUp(req)
}