Release v0.1.0

vendor/github.com/lightninglabs/neutrino/banman/util.go

@@ -0,0 +1,48 @@
+package banman
+
+import (
+	"net"
+)
+
+var (
+	// defaultIPv4Mask is the default IPv4 mask used when parsing IP
+	// networks from an address. This ensures that the IP network only
+	// contains *one* IP address -- the one specified.
+	defaultIPv4Mask = net.CIDRMask(32, 32)
+
+	// defaultIPv6Mask is the default IPv6 mask used when parsing IP
+	// networks from an address. This ensures that the IP network only
+	// contains *one* IP address -- the one specified.
+	defaultIPv6Mask = net.CIDRMask(128, 128)
+)
+
+// ParseIPNet parses the IP network that contains the given address. An optional
+// mask can be provided, to expand the scope of the IP network, otherwise the
+// IP's default is used.
+//
+// NOTE: This assumes that the address has already been resolved.
+func ParseIPNet(addr string, mask net.IPMask) (*net.IPNet, error) {
+	// If the address includes a port, we'll remove it.
+	host, _, err := net.SplitHostPort(addr)
+	if err != nil {
+		// Address doesn't include a port.
+		host = addr
+	}
+
+	// Parse the IP from the host to ensure it is supported.
+	ip := net.ParseIP(host)
+	switch {
+	case ip.To4() != nil:
+		if mask == nil {
+			mask = defaultIPv4Mask
+		}
+	case ip.To16() != nil:
+		if mask == nil {
+			mask = defaultIPv6Mask
+		}
+	default:
+		return nil, ErrUnsupportedIP
+	}
+
+	return &net.IPNet{IP: ip.Mask(mask), Mask: mask}, nil
+}