1 files changed, 24 insertions, 0 deletions

diff --git a/util/ip.go b/util/ip.go
new file mode 100644
index 0000000..f86d5b5
--- /dev/null
+++ b/util/ip.go
@@ -0,0 +1,24 @@
+package util
+
+import (
+        "net"
+        "regexp"
+)
+
+// Parses an IPv4 or IPv6 address with an optional port on the end. Returns
+// match groups for the addresses. The first match is the IPv6 address and the
+// second the IPv4 address.
+var ipRegexp = regexp.MustCompile(`(?:\[([0-9a-f:]+)\]|(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}))(?::\d+)?`)
+
+func ParseIP(s string) net.IP {
+        ips := ipRegexp.FindStringSubmatch(s)
+        if ips == nil {
+                return nil
+        }
+
+        if v6, v4 := ips[1], ips[2]; v6 != "" {
+                return net.ParseIP(v6)
+        } else {
+                return net.ParseIP(v4)
+        }
+}