add ip util to sdk

sdk/base/lib/util/ip.ts

@@ -0,0 +1,74 @@
+export class IpAddress {
+  readonly octets: number[]
+  constructor(readonly address: string) {
+    if (address.includes(":")) {
+      this.octets = new Array(16).fill(0)
+      const segs = address.split(":")
+      let idx = 0
+      let octIdx = 0
+      while (segs[idx]) {
+        const num = parseInt(segs[idx], 16)
+        this.octets[octIdx++] = num >> 8
+        this.octets[octIdx++] = num & 255
+        idx += 1
+      }
+      if (idx < 7) {
+        idx = segs.length - 1
+        octIdx = 15
+        while (segs[idx]) {
+          const num = parseInt(segs[idx], 16)
+          this.octets[octIdx--] = num & 255
+          this.octets[octIdx--] = num >> 8
+          idx -= 1
+        }
+      }
+    } else {
+      this.octets = address.split(".").map(Number)
+      if (this.octets.length !== 4) throw new Error("invalid ipv4 address")
+    }
+    if (this.octets.some((o) => o >= 256)) {
+      throw new Error("invalid ip address")
+    }
+  }
+  isIpv4(): boolean {
+    return this.octets.length === 4
+  }
+  isIpv6(): boolean {
+    return this.octets.length === 16
+  }
+  isPublic(): boolean {
+    return this.isIpv4() && !PRIVATE_IPV4_RANGES.some((r) => r.contains(this))
+  }
+}
+
+export class IpNet extends IpAddress {
+  readonly prefix
+  constructor(readonly ipnet: string) {
+    const [address, prefixStr] = ipnet.split("/", 2)
+    super(address)
+    this.prefix = Number(prefixStr)
+  }
+  contains(address: string | IpAddress): boolean {
+    if (typeof address === "string") address = new IpAddress(address)
+    if (this.octets.length !== address.octets.length) return false
+    let prefix = this.prefix
+    let idx = 0
+    while (idx < this.octets.length && prefix >= 8) {
+      if (this.octets[idx] !== address.octets[idx]) {
+        return false
+      }
+      idx += 1
+      prefix -= 8
+    }
+    if (prefix === 0 || idx >= this.octets.length) return true
+    const mask = 255 << prefix
+    return (this.octets[idx] & mask) === (address.octets[idx] & mask)
+  }
+}
+
+export const PRIVATE_IPV4_RANGES = [
+  new IpNet("127.0.0.0/8"),
+  new IpNet("10.0.0.0/8"),
+  new IpNet("172.16.0.0/12"),
+  new IpNet("192.168.0.0/16"),
+]