Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/yhy0/chying-agent/cryptographynpx skills add yhy0/CHYing-agent --skill cryptographygit clone --depth 1 https://github.com/yhy0/CHYing-agentWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/yhy0/chying-agent/cryptography)<a href="https://agentmods.dev/skills/yhy0/chying-agent/cryptography"><img src="https://agentmods.dev/badge/skills/yhy0/chying-agent/cryptography.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00022 | $0.11145 |
| Opus 5 | $0.00011 | $0.05573 |
| Sonnet 5 | $0.00004 | $0.02229 |
| Haiku 4.5 | $0.00002 | $0.01115 |
Grade A, and why
cryptography scanned grade A with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 5d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
# r = requests.post(URL, data={'ct': payload.hex()}) How it starts
The opening of the file, as written. The whole thing — 990 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CTF Crypto Solver Skill
Core Objective
你是一个专业的 CTF Crypto 解题助手。你的目标是：
- 识别加密类型 — 从参数、代码、输出特征判断
- 查阅攻击模块 — Read 对应 module 获取完整攻击代码
- 选择最优攻击 — 按 dispatch table 优先级执行
- 生成可运行脚本 — 直接产出 exploit，不做空泛分析
关键原则：modules/ 下有 14 个文件包含完整攻击代码和真实 CTF writeup。本文件是调度入口，详细实现务必 Read 对应 module。
标准解题流程
1. 读题 → 提取参数 (n/e/c, key/iv/mode, ciphertext, source code)
2. 查 dispatch table → 匹配加密类型 + 识别漏洞模式
3. 快速尝试 "first try" 命令 (RsaCtfTool / factordb / 直接数学)
4. 若 first try 失败 → Read 对应 module 获取高级攻击
5. 编写并运行完整 exploit 脚本
6. 提取 flag → 验证格式
Dispatch Table — 密码类型识别与攻击路由
1. RSA
识别特征: 出现 n, e, c 参数；.pem 公钥文件；pow(m, e, n) 代码；大整数（通常 >256 位）
| 漏洞模式 | 识别方法 | 攻击 | 说明 |
|---|---|---|---|
| 小 n | n < 512 bit | factordb / yafu | 直接分解 |
| 小 e (e=3) | e ≤ 5 且 c 较小 | 整数开根 gmpy2.iroot(c,e) |
m^e 未超过 n 则直接开根 |
| 共模攻击 | 同 n 不同 e 加密同一 m | 扩展 GCD | gcd(e1,e2)=1 时恢复 m |
| Wiener | e 很大 (接近 n) | 连分数展开 | d < n^0.25 / 3 |
| Fermat | p, q 相近 | Fermat 分解 | |p-q| < n^(1/4) |
| Pollard p-1 | p-1 只含小因子 | Pollard p-1 | B-smooth 的 p-1 |
| Hastad 广播 | 同 m 用不同 n 加密, 小 e | CRT + 开根 | 需 e 组密文 |
| Coppersmith | 已知明文高位/部分 p | SageMath small_roots() |
最强通用攻击 |
| Batch GCD | 多个 n 共享素因子 | gcd(n1, n2) |
多密钥场景 |
| dp/dq 泄露 | 已知 dp, dq, qinv | CRT 直接解密 | 部分私钥恢复 |
| CRT 故障 | 一次正确一次错误签名 | gcd(s_bad^e - m, n) |
故障注入场景 |
| e 与 phi 不互素 | gcd(e, phi) > 1 |
CRT + nthroot_mod per prime | 需分解 n |
| p = q | n 是完全平方 | gmpy2.isqrt(n) 检测 |
phi = p*(p-1) |
First try:
# 自动化尝试所有已知攻击
rsactftool --publickey pub.pem --private --attack all
# 或指定参数
rsactftool -n $N -e $E --uncipher $C --attack all
# factordb 查询
from factordb.factordb import FactorDB
f = FactorDB(n)
f.connect()
factors = f.get_factor_list()
if len(factors) >= 2:
p, q = factors[0], factors[1]
详细攻击代码 → Read modules/rsa-attacks.md (基础攻击: small e, common modulus, Wiener, Pollard, Hastad, Coppersmith, Manger oracle)
高级技术 → Read modules/rsa-attacks-2.md (batch GCD, dp/dq 恢复, CRT fault, 同态 oracle, p=q bypass)
RSA 基础流程 → Read modules/rsa.md
What ships with it
14 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
- docs/QUICKREF.md 1.9 KB
- modules/advanced-math.md 23 KB
- modules/classic-ciphers.md 22 KB
- modules/ecc-attacks.md 11 KB
- modules/exotic-crypto.md 24 KB
- modules/historical.md 4.5 KB
- modules/modern-ciphers-2.md 35 KB
- modules/modern-ciphers.md 20 KB
- modules/prng.md 24 KB
- modules/rsa-attacks-2.md 13 KB
- modules/rsa-attacks.md 16 KB
- modules/rsa.md 6.3 KB
- modules/stream-ciphers.md 11 KB
- modules/zkp-and-advanced.md 19 KB
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 5d ago First seen · 990 lines · 22 tokens per session scan A 616aed674121
cryptography is a skill published in the GitHub repository yhy0/CHYing-agent (549 stars, last pushed 4mo ago), licensed MIT. It adds 22 tokens to every session and 11,145 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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brainstorming
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auto-perf-optimize
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chat-perf
Run chat perf benchmarks and memory leak checks against the local dev build or any published VS Code version. Use when investigating chat rendering regressions, validating perf-sensitive changes to chat UI, or checking for memory leaks in the chat response pipeline.
chat-pet-sprite-creation
Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.
cpu-profile-analysis
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