github.com/EagleQL/Xray-core@v1.4.3/app/dns/hosts.go (about)

     1  package dns
     2  
     3  import (
     4  	"github.com/xtls/xray-core/common"
     5  	"github.com/xtls/xray-core/common/net"
     6  	"github.com/xtls/xray-core/common/strmatcher"
     7  	"github.com/xtls/xray-core/features"
     8  	"github.com/xtls/xray-core/features/dns"
     9  )
    10  
    11  // StaticHosts represents static domain-ip mapping in DNS server.
    12  type StaticHosts struct {
    13  	ips      [][]net.Address
    14  	matchers *strmatcher.MatcherGroup
    15  }
    16  
    17  var typeMap = map[DomainMatchingType]strmatcher.Type{
    18  	DomainMatchingType_Full:      strmatcher.Full,
    19  	DomainMatchingType_Subdomain: strmatcher.Domain,
    20  	DomainMatchingType_Keyword:   strmatcher.Substr,
    21  	DomainMatchingType_Regex:     strmatcher.Regex,
    22  }
    23  
    24  func toStrMatcher(t DomainMatchingType, domain string) (strmatcher.Matcher, error) {
    25  	strMType, f := typeMap[t]
    26  	if !f {
    27  		return nil, newError("unknown mapping type", t).AtWarning()
    28  	}
    29  	matcher, err := strMType.New(domain)
    30  	if err != nil {
    31  		return nil, newError("failed to create str matcher").Base(err)
    32  	}
    33  	return matcher, nil
    34  }
    35  
    36  // NewStaticHosts creates a new StaticHosts instance.
    37  func NewStaticHosts(hosts []*Config_HostMapping, legacy map[string]*net.IPOrDomain) (*StaticHosts, error) {
    38  	g := new(strmatcher.MatcherGroup)
    39  	sh := &StaticHosts{
    40  		ips:      make([][]net.Address, len(hosts)+len(legacy)+16),
    41  		matchers: g,
    42  	}
    43  
    44  	if legacy != nil {
    45  		features.PrintDeprecatedFeatureWarning("simple host mapping")
    46  
    47  		for domain, ip := range legacy {
    48  			matcher, err := strmatcher.Full.New(domain)
    49  			common.Must(err)
    50  			id := g.Add(matcher)
    51  
    52  			address := ip.AsAddress()
    53  			if address.Family().IsDomain() {
    54  				return nil, newError("invalid domain address in static hosts: ", address.Domain()).AtWarning()
    55  			}
    56  
    57  			sh.ips[id] = []net.Address{address}
    58  		}
    59  	}
    60  
    61  	for _, mapping := range hosts {
    62  		matcher, err := toStrMatcher(mapping.Type, mapping.Domain)
    63  		if err != nil {
    64  			return nil, newError("failed to create domain matcher").Base(err)
    65  		}
    66  		id := g.Add(matcher)
    67  		ips := make([]net.Address, 0, len(mapping.Ip)+1)
    68  		switch {
    69  		case len(mapping.Ip) > 0:
    70  			for _, ip := range mapping.Ip {
    71  				addr := net.IPAddress(ip)
    72  				if addr == nil {
    73  					return nil, newError("invalid IP address in static hosts: ", ip).AtWarning()
    74  				}
    75  				ips = append(ips, addr)
    76  			}
    77  
    78  		case len(mapping.ProxiedDomain) > 0:
    79  			ips = append(ips, net.DomainAddress(mapping.ProxiedDomain))
    80  
    81  		default:
    82  			return nil, newError("neither IP address nor proxied domain specified for domain: ", mapping.Domain).AtWarning()
    83  		}
    84  
    85  		// Special handling for localhost IPv6. This is a dirty workaround as JSON config supports only single IP mapping.
    86  		if len(ips) == 1 && ips[0] == net.LocalHostIP {
    87  			ips = append(ips, net.LocalHostIPv6)
    88  		}
    89  
    90  		sh.ips[id] = ips
    91  	}
    92  
    93  	return sh, nil
    94  }
    95  
    96  func filterIP(ips []net.Address, option dns.IPOption) []net.Address {
    97  	filtered := make([]net.Address, 0, len(ips))
    98  	for _, ip := range ips {
    99  		if (ip.Family().IsIPv4() && option.IPv4Enable) || (ip.Family().IsIPv6() && option.IPv6Enable) {
   100  			filtered = append(filtered, ip)
   101  		}
   102  	}
   103  	if len(filtered) == 0 {
   104  		return nil
   105  	}
   106  	return filtered
   107  }
   108  
   109  // LookupIP returns IP address for the given domain, if exists in this StaticHosts.
   110  func (h *StaticHosts) LookupIP(domain string, option dns.IPOption) []net.Address {
   111  	indices := h.matchers.Match(domain)
   112  	if len(indices) == 0 {
   113  		return nil
   114  	}
   115  	ips := []net.Address{}
   116  	for _, id := range indices {
   117  		ips = append(ips, h.ips[id]...)
   118  	}
   119  	if len(ips) == 1 && ips[0].Family().IsDomain() {
   120  		return ips
   121  	}
   122  	return filterIP(ips, option)
   123  }