dsh-ipcalc

IP & subnet math toolbox for DeepSeek Harness (dsh). Three pure-math tools — zero runtime dependencies, no network I/O — so agents stop doing subnet arithmetic in their heads (where they frequently get it wrong).

Tools

Tool	What it does
ipv4_subnet	Full subnet layout for an IPv4 CIDR: network, broadcast, netmask, wildcard, host range, address counts, integer forms and IANA classes
ipv4_summarize	Reduce a list of IPv4 addresses/ranges to the minimal covering CIDR list (merge + supernet)
ip_parse	Validate, normalize (RFC 5952) and classify any IPv4/IPv6 address, including embedded IPv4-in-IPv6 forms

Install

dsh plugin --profile <your-profile> add github:TYEclipse/dsh-ipcalc

Usage

ipv4_subnet("192.168.1.25/24")
→ network 192.168.1.0/24
  netmask 255.255.255.0  wildcard 0.0.0.255  broadcast 192.168.1.255
  host range 192.168.1.1 – 192.168.1.254  (254 usable of 256)
  classes: network=private  host=private

ipv4_subnet("10.10.10.10/255.255.255.248")   # dotted-mask input works too
→ network 10.10.10.8/29  (6 usable hosts)

ipv4_summarize(["10.0.0.0/24", "10.0.1.0/24", "10.0.2.0/24", "10.0.3.0/24"])
→ ["10.0.0.0/22"]

ip_parse("::ffff:192.168.1.1")
→ IPv6, class ipv4_mapped, normalized ::ffff:c0a8:101 (embeds 192.168.1.1)

Semantics

• Exact arithmetic — all math uses plain double arithmetic on 32-bit integers (values up to 2³² are exactly representable), so there is no bitwise-overflow risk.
• /31 follows RFC 3021 — both addresses are reported as usable (point-to-point links).
• /32 is a single host — first/last host equal the address itself.
• Bare addresses are treated as /32; dotted netmasks (/255.255.255.248) are accepted anywhere a prefix length is; non-contiguous masks are rejected.
• RFC 5952 canonicalization — IPv6 is lowercased, leading zeros stripped, and the longest (leftmost on ties) run of two or more zero hextets compressed to ::.
• Classification follows the IANA special-purpose registries: IPv4 unspecified / broadcast / loopback / private (10/8, 172.16/12, 192.168/16) / cgnat (100.64/10) / link_local (169.254/16) / documentation (192.0.2/24, 198.51.100/24, 203.0.113/24) / multicast (224/4) / reserved (240/4) / global; IPv6 unspecified / loopback / ipv4_mapped / ipv4_compatible / documentation (2001:db8::/32) / link_local (fe80::/10) / multicast (ff00::/8) / unique_local (fc00::/7) / global. Classification is best-effort for the common registry entries, not a full CIDR-overlap engine.

Development

pnpm install
pnpm build
pnpm test
pnpm lint

License

MIT

---

dsh-ipcalc（中文简介）

面向 DeepSeek Harness 的 IP 与子网数学工具箱，三个纯本地计算工具，零运行时依赖、无任何网络访问：

• ipv4_subnet：给定 CIDR（支持 a.b.c.d/前缀、点分掩码、裸地址）输出完整子网布局——网络号、广播地址、子网掩码、反掩码、可用主机范围与数量、整数形式、IANA 分类（私网/环回/链路本地/CGNAT/文档段/组播/保留段等）。
• ipv4_summarize：把一组 IPv4 地址/网段归并成最小覆盖 CIDR 列表（相邻合并 + 对齐超网）。
• ip_parse：校验、规范化（RFC 5952）并分类任意 IPv4/IPv6 地址，识别 ::ffff:a.b.c.d 内嵌 IPv4 形式。

专门解决大模型心算子网边界常出错的问题；/31 遵循 RFC 3021，/32 视为单主机。