From b4d45306b2ae338ea621b7cacd9701e801abb392 Mon Sep 17 00:00:00 2001
From: Matt Layher <mlayher@digitalocean.com>
Date: Fri, 9 Oct 2015 10:52:05 -0400
Subject: [PATCH] datasource, network: add support for DigitalOcean floating
 IPs

---
 datasource/metadata/digitalocean/metadata.go |  9 ++-
 network/digitalocean.go                      | 26 +++++++
 network/digitalocean_test.go                 | 79 ++++++++++++++++++++
 3 files changed, 110 insertions(+), 4 deletions(-)

diff --git a/datasource/metadata/digitalocean/metadata.go b/datasource/metadata/digitalocean/metadata.go
index d8b71ae..fa6c605 100644
--- a/datasource/metadata/digitalocean/metadata.go
+++ b/datasource/metadata/digitalocean/metadata.go
@@ -38,10 +38,11 @@ type Address struct {
 }
 
 type Interface struct {
-	IPv4 *Address `json:"ipv4"`
-	IPv6 *Address `json:"ipv6"`
-	MAC  string   `json:"mac"`
-	Type string   `json:"type"`
+	IPv4       *Address `json:"ipv4"`
+	IPv6       *Address `json:"ipv6"`
+	AnchorIPv4 *Address `json:"anchor_ipv4"`
+	MAC        string   `json:"mac"`
+	Type       string   `json:"type"`
 }
 
 type Interfaces struct {
diff --git a/network/digitalocean.go b/network/digitalocean.go
index f31f989..c3d5daa 100644
--- a/network/digitalocean.go
+++ b/network/digitalocean.go
@@ -126,6 +126,32 @@ func parseInterface(iface digitalocean.Interface, nameservers []net.IP, useRoute
 			})
 		}
 	}
+	if iface.AnchorIPv4 != nil {
+		var ip, mask, gateway net.IP
+		if ip = net.ParseIP(iface.AnchorIPv4.IPAddress); ip == nil {
+			return nil, fmt.Errorf("could not parse %q as anchor IPv4 address", iface.AnchorIPv4.IPAddress)
+		}
+		if mask = net.ParseIP(iface.AnchorIPv4.Netmask); mask == nil {
+			return nil, fmt.Errorf("could not parse %q as anchor IPv4 mask", iface.AnchorIPv4.Netmask)
+		}
+		addresses = append(addresses, net.IPNet{
+			IP:   ip,
+			Mask: net.IPMask(mask),
+		})
+
+		if useRoute {
+			if gateway = net.ParseIP(iface.AnchorIPv4.Gateway); gateway == nil {
+				return nil, fmt.Errorf("could not parse %q as anchor IPv4 gateway", iface.AnchorIPv4.Gateway)
+			}
+			routes = append(routes, route{
+				destination: net.IPNet{
+					IP:   net.IPv4zero,
+					Mask: net.IPMask(net.IPv4zero),
+				},
+				gateway: gateway,
+			})
+		}
+	}
 
 	hwaddr, err := net.ParseMAC(iface.MAC)
 	if err != nil {
diff --git a/network/digitalocean_test.go b/network/digitalocean_test.go
index ec07c9b..78aca54 100644
--- a/network/digitalocean_test.go
+++ b/network/digitalocean_test.go
@@ -258,6 +258,85 @@ func TestParseInterface(t *testing.T) {
 				},
 			},
 		},
+
+		{
+			cfg: digitalocean.Interface{
+				MAC: "01:23:45:67:89:AB",
+				AnchorIPv4: &digitalocean.Address{
+					IPAddress: "bad",
+					Netmask:   "255.255.0.0",
+				},
+			},
+			nss: []net.IP{},
+			err: errors.New("could not parse \"bad\" as anchor IPv4 address"),
+		},
+		{
+			cfg: digitalocean.Interface{
+				MAC: "01:23:45:67:89:AB",
+				AnchorIPv4: &digitalocean.Address{
+					IPAddress: "1.2.3.4",
+					Netmask:   "bad",
+				},
+			},
+			nss: []net.IP{},
+			err: errors.New("could not parse \"bad\" as anchor IPv4 mask"),
+		},
+		{
+			cfg: digitalocean.Interface{
+				MAC: "01:23:45:67:89:AB",
+				AnchorIPv4: &digitalocean.Address{
+					IPAddress: "1.2.3.4",
+					Netmask:   "255.255.0.0",
+					Gateway:   "bad",
+				},
+			},
+			useRoute: true,
+			nss:      []net.IP{},
+			err:      errors.New("could not parse \"bad\" as anchor IPv4 gateway"),
+		},
+		{
+			cfg: digitalocean.Interface{
+				MAC: "01:23:45:67:89:AB",
+				IPv4: &digitalocean.Address{
+					IPAddress: "1.2.3.4",
+					Netmask:   "255.255.0.0",
+					Gateway:   "5.6.7.8",
+				},
+				AnchorIPv4: &digitalocean.Address{
+					IPAddress: "7.8.9.10",
+					Netmask:   "255.255.0.0",
+					Gateway:   "11.12.13.14",
+				},
+			},
+			useRoute: true,
+			nss:      []net.IP{},
+			iface: &logicalInterface{
+				hwaddr: net.HardwareAddr([]byte{0x01, 0x23, 0x45, 0x67, 0x89, 0xab}),
+				config: configMethodStatic{
+					addresses: []net.IPNet{
+						{
+							IP:   net.ParseIP("1.2.3.4"),
+							Mask: net.IPMask(net.ParseIP("255.255.0.0")),
+						},
+						{
+							IP:   net.ParseIP("7.8.9.10"),
+							Mask: net.IPMask(net.ParseIP("255.255.0.0")),
+						},
+					},
+					nameservers: []net.IP{},
+					routes: []route{
+						{
+							net.IPNet{IP: net.IPv4zero, Mask: net.IPMask(net.IPv4zero)},
+							net.ParseIP("5.6.7.8"),
+						},
+						{
+							net.IPNet{IP: net.IPv4zero, Mask: net.IPMask(net.IPv4zero)},
+							net.ParseIP("11.12.13.14"),
+						},
+					},
+				},
+			},
+		},
 	} {
 		iface, err := parseInterface(tt.cfg, tt.nss, tt.useRoute)
 		if !errorsEqual(tt.err, err) {