ooni-probe-cli/internal/engine/netx/resolver/bogon.go
Simone Basso 83440cf110
refactor: split errorsx in good and legacy (#477)
The legacy part for now is internal/errorsx. It will stay there until
I figure out whether it also needs some extra bug fixing.

The good part is now in internal/netxlite/errorsx and contains all the
logic for mapping errors. We need to further improve upon this logic
by writing more thorough integration tests for QUIC.

We also need to copy the various dialer, conn, etc adapters that set
errors. We will put them inside netxlite and we will generate errors in
a way that is less crazy with respect to the major operation. (The
idea is to always wrap, given that now we measure in an incremental way
and we don't measure every operation together.)

Part of https://github.com/ooni/probe/issues/1591
2021-09-07 17:09:30 +02:00

75 lines
1.9 KiB
Go

package resolver
import (
"context"
"net"
"github.com/ooni/probe-cli/v3/internal/netxlite/errorsx"
"github.com/ooni/probe-cli/v3/internal/runtimex"
)
var privateIPBlocks []*net.IPNet
func init() {
for _, cidr := range []string{
"0.0.0.0/8", // "This" network (however, Linux...)
"10.0.0.0/8", // RFC1918
"100.64.0.0/10", // Carrier grade NAT
"127.0.0.0/8", // IPv4 loopback
"169.254.0.0/16", // RFC3927 link-local
"172.16.0.0/12", // RFC1918
"192.168.0.0/16", // RFC1918
"224.0.0.0/4", // Multicast
"::1/128", // IPv6 loopback
"fe80::/10", // IPv6 link-local
"fc00::/7", // IPv6 unique local addr
} {
_, block, err := net.ParseCIDR(cidr)
runtimex.PanicOnError(err, "net.ParseCIDR failed")
privateIPBlocks = append(privateIPBlocks, block)
}
}
func isPrivate(ip net.IP) bool {
if ip.IsLoopback() || ip.IsLinkLocalUnicast() || ip.IsLinkLocalMulticast() {
return true
}
for _, block := range privateIPBlocks {
if block.Contains(ip) {
return true
}
}
return false
}
// IsBogon returns whether if an IP address is bogon. Passing to this
// function a non-IP address causes it to return bogon.
func IsBogon(address string) bool {
ip := net.ParseIP(address)
return ip == nil || isPrivate(ip)
}
// BogonResolver is a bogon aware resolver. When a bogon is encountered in
// a reply, this resolver will return an error.
//
// Deprecation warning
//
// This resolver is deprecated. The right thing to do would be to check
// for bogons right after a domain name resolution in the nettest.
type BogonResolver struct {
Resolver
}
// LookupHost implements Resolver.LookupHost
func (r BogonResolver) LookupHost(ctx context.Context, hostname string) ([]string, error) {
addrs, err := r.Resolver.LookupHost(ctx, hostname)
for _, addr := range addrs {
if IsBogon(addr) {
return nil, errorsx.ErrDNSBogon
}
}
return addrs, err
}
var _ Resolver = BogonResolver{}