Vendored go-sockaddr and go-sockaddr/template

vendor/github.com/hashicorp/go-sockaddr/ifaddrs.go

@@ -1,6 +1,7 @@
 package sockaddr
 
 import (
+	"encoding/binary"
 	"errors"
 	"fmt"
 	"math/big"
@@ -15,7 +16,7 @@ var (
 	// Centralize all regexps and regexp.Copy() where necessary.
 	signRE       *regexp.Regexp = regexp.MustCompile(`^[\s]*[+-]`)
 	whitespaceRE *regexp.Regexp = regexp.MustCompile(`[\s]+`)
-	ifNameRE     *regexp.Regexp = regexp.MustCompile(`^Ethernet adapter ([^\s:]+):`)
+	ifNameRE     *regexp.Regexp = regexp.MustCompile(`^Ethernet adapter ([^:]+):`)
 	ipAddrRE     *regexp.Regexp = regexp.MustCompile(`^   IPv[46] Address\. \. \. \. \. \. \. \. \. \. \. : ([^\s]+)`)
 )
 
@@ -866,6 +867,80 @@ func IfAddrMath(operation, value string, inputIfAddr IfAddr) (IfAddr, error) {
 		default:
 			return IfAddr{}, fmt.Errorf("unsupported type for operation %q: %T", operation, sockType)
 		}
+	case "mask":
+		// "mask" operates on the IP address and returns the IP address on
+		// which the given integer mask has been applied. If the applied mask
+		// corresponds to a larger network than the mask of the IP address,
+		// the latter will be replaced by the former.
+		switch sockType := inputIfAddr.SockAddr.Type(); sockType {
+		case TypeIPv4:
+			i, err := strconv.ParseUint(value, 10, 32)
+			if err != nil {
+				return IfAddr{}, fmt.Errorf("unable to convert %q to int for operation %q: %v", value, operation, err)
+			}
+
+			if i > 32 {
+				return IfAddr{}, fmt.Errorf("parameter for operation %q on ipv4 addresses must be between 0 and 32", operation)
+			}
+
+			ipv4 := *ToIPv4Addr(inputIfAddr.SockAddr)
+
+			ipv4Mask := net.CIDRMask(int(i), 32)
+			ipv4MaskUint32 := binary.BigEndian.Uint32(ipv4Mask)
+
+			maskedIpv4 := ipv4.NetIP().Mask(ipv4Mask)
+			maskedIpv4Uint32 := binary.BigEndian.Uint32(maskedIpv4)
+
+			maskedIpv4MaskUint32 := uint32(ipv4.Mask)
+
+			if ipv4MaskUint32 < maskedIpv4MaskUint32 {
+				maskedIpv4MaskUint32 = ipv4MaskUint32
+			}
+
+			return IfAddr{
+				SockAddr: IPv4Addr{
+					Address: IPv4Address(maskedIpv4Uint32),
+					Mask:    IPv4Mask(maskedIpv4MaskUint32),
+				},
+				Interface: inputIfAddr.Interface,
+			}, nil
+		case TypeIPv6:
+			i, err := strconv.ParseUint(value, 10, 32)
+			if err != nil {
+				return IfAddr{}, fmt.Errorf("unable to convert %q to int for operation %q: %v", value, operation, err)
+			}
+
+			if i > 128 {
+				return IfAddr{}, fmt.Errorf("parameter for operation %q on ipv6 addresses must be between 0 and 64", operation)
+			}
+
+			ipv6 := *ToIPv6Addr(inputIfAddr.SockAddr)
+
+			ipv6Mask := net.CIDRMask(int(i), 128)
+			ipv6MaskBigInt := new(big.Int)
+			ipv6MaskBigInt.SetBytes(ipv6Mask)
+
+			maskedIpv6 := ipv6.NetIP().Mask(ipv6Mask)
+			maskedIpv6BigInt := new(big.Int)
+			maskedIpv6BigInt.SetBytes(maskedIpv6)
+
+			maskedIpv6MaskBigInt := new(big.Int)
+			maskedIpv6MaskBigInt.Set(ipv6.Mask)
+
+			if ipv6MaskBigInt.Cmp(maskedIpv6MaskBigInt) == -1 {
+				maskedIpv6MaskBigInt = ipv6MaskBigInt
+			}
+
+			return IfAddr{
+				SockAddr: IPv6Addr{
+					Address: IPv6Address(maskedIpv6BigInt),
+					Mask:    IPv6Mask(maskedIpv6MaskBigInt),
+				},
+				Interface: inputIfAddr.Interface,
+			}, nil
+		default:
+			return IfAddr{}, fmt.Errorf("unsupported type for operation %q: %T", operation, sockType)
+		}
 	default:
 		return IfAddr{}, fmt.Errorf("unsupported math operation: %q", operation)
 	}

vendor/github.com/hashicorp/go-sockaddr/sockaddr.go

@@ -1,6 +1,7 @@
 package sockaddr
 
 import (
+	"encoding/json"
 	"fmt"
 	"strings"
 )
@@ -176,3 +177,30 @@ func sockAddrInit() {
 func SockAddrAttrs() []AttrName {
 	return sockAddrAttrs
 }
+
+// Although this is pretty trivial to do in a program, having the logic here is
+// useful all around. Note that this marshals into a *string* -- the underlying
+// string representation of the sockaddr. If you then unmarshal into this type
+// in Go, all will work as expected, but externally you can take what comes out
+// and use the string value directly.
+type SockAddrMarshaler struct {
+	SockAddr
+}
+
+func (s *SockAddrMarshaler) MarshalJSON() ([]byte, error) {
+	return json.Marshal(s.SockAddr.String())
+}
+
+func (s *SockAddrMarshaler) UnmarshalJSON(in []byte) error {
+	var str string
+	err := json.Unmarshal(in, &str)
+	if err != nil {
+		return err
+	}
+	sa, err := NewSockAddr(str)
+	if err != nil {
+		return err
+	}
+	s.SockAddr = sa
+	return nil
+}

vendor/github.com/hashicorp/go-sockaddr/template/doc.go

@@ -212,6 +212,13 @@ Supported operations include:
     from the network's broadcast address (e.g. 127.0.0.1 `"network" "-1"` will
     return "127.255.255.255").  Values that overflow the network size will
     safely wrap.
+  - `mask`: Applies the given network mask to the address. The network mask is
+  	expressed as a decimal value (e.g. network mask "24" corresponds to
+  	`255.255.255.0`). After applying the network mask, the network mask of the
+  	resulting address will be either the applied network mask or the network mask
+  	of the input address depending on which network is larger
+  	(e.g. 192.168.10.20/24 `"mask" "16"` will return "192.168.0.0/16" but
+  	192.168.10.20/24 `"mask" "28"` will return "192.168.10.16/24").
 
 Example:
 
@@ -219,6 +226,7 @@ Example:
     {{ GetPrivateInterfaces | include "type" "IP" | math "address" "-256" | attr "address" }}
     {{ GetPrivateInterfaces | include "type" "IP" | math "network" "+2" | attr "address" }}
     {{ GetPrivateInterfaces | include "type" "IP" | math "network" "-2" | attr "address" }}
+    {{ GetPrivateInterfaces | include "type" "IP" | math "mask" "24" | attr "address" }}
     {{ GetPrivateInterfaces | include "flags" "forwardable|up" | include "type" "IPv4" | math "network" "+2" | attr "address" }}