Capability Matrix

能力账本

已实现 / 已验证能力

HTTP/1.1（RFC 9110/9112）

• 请求体支持 Content-Length、库生成 chunked 与真流式上传：高层 BodyCreateStream / 底层 KhHttpRequestSetBodySource 按块读取；用户手设 Transfer-Encoding/TE 仍安全拒绝；Trailer 头仅在 chunked 请求 trailer 场景允许。
• 请求 trailer：KhHttpRequestAddTrailer / khttp::RequestAddTrailer 在 Chunked body 模式下发送终止块后的 trailer 字段，并拒绝禁止字段与 CRLF 注入。
• 响应解析：状态行仅接受 HTTP/1.0、1.1；头行 ≤8 KiB、头段 ≤64 KiB、头数 ≤200；拒绝 obs-fold 折行；多个 Content-Length、TE+CL 冲突 → STATUS_INVALID_NETWORK_RESPONSE。
• body 框定：Content-Length / chunked / close-delimited；无 body 状态：1xx、204、205、304，及 HEAD 响应。
• chunked：块数 ≤8192、chunk-size 行 ≤32、严格 chunk 扩展语法校验；trailer 校验并拒绝禁止字段（Content-Length/Transfer-Encoding/Host/Authorization/Proxy-Authorization/Cookie/Set-Cookie）。
• 206 Partial Content / Content-Range 提供只读解析（HttpResponse::IsPartialContent / GetContentRange），请求侧 Range 与条件请求仍按普通额外头透传。
• Content-Encoding 解码：gzip（校验 CRC32+ISIZE+头 CRC16）、deflate（自动识别 zlib 包装并校验 Adler-32，底层用内核 RtlDecompressBufferEx，带运行时探测）、br（内置 Brotli）、compress（完整 LZW .Z）、identity；最多 2 级链，反序解码。
• 解压炸弹防护：decoded aggregate 跟随响应/调用方容量，单级膨胀比 ≤64（MaxDecodeExpansionRatio）。
• 中间 1xx（除 101）静默吞掉重解析；SendFlagExpectContinue 显式开启 Expect: 100-continue，覆盖 100 后发送 body、final/417 不发送 body、超时后发送 body 与断连错误；自动 redirect、keep-alive 连接池复用。
• HTTP proxy：HTTPS 走 CONNECT 隧道；明文 HTTP over proxy 使用 absolute-form request target，Proxy-Authorization 只来自显式代理配置。

HTTP/2（RFC 9113 + HPACK RFC 7541）

• 连接前导 + SETTINGS 交换；客户端发 7 项 SETTINGS（含 ENABLE_CONNECT_PROTOCOL）、立即发 ACK 不阻塞等服务端 ACK。
• SETTINGS 校验：ENABLE_PUSH != 0 拒绝、ENABLE_CONNECT_PROTOCOL 仅接受 0/1、窗口/帧大小越界拒绝；缺 ACK 且后续读超时 → GOAWAY SETTINGS_TIMEOUT。
• 完整帧矩阵；伪头/流控/连接专属头校验；:status 必须先于普通头。
• CONTINUATION 洪泛防护：≤64 帧、≤4 空帧（CVE-2024-27316 类）。
• 活动 stream 表 + BeginRequest / ReceiveResponse(streamId) 两阶段接口；HEADERS/DATA/WINDOW_UPDATE/RST_STREAM 按 streamId 交错分发。
• 高层 khttp 连接池接入 HTTP/2 stream 租约，同源 H2 连接可按本地/peer 并发上限承载多个活动请求；连接级错误广播给活动流。
• DATA 流控：连接级 + per-stream 窗口；连接级 WINDOW_UPDATE 阈值为初始窗口一半（32767）；初始窗口 SETTINGS 更新会同步调整活动 stream；越界 GOAWAY FLOW_CONTROL_ERROR。
• 1xx interim 处理（拒绝 :status 101 与 interim+END_STREAM）；PUSH_PROMISE 一律协议错误。
• RFC 8441 extended CONNECT：CONNECT + :protocol: websocket 需对端 SETTINGS_ENABLE_CONNECT_PROTOCOL=1；低层 SendStreamData / ReceiveStreamData 可承载 WebSocket frame bytes，高层 kws 可在显式 opt-in 后走该路径。
• 三模式：TLS-ALPN h2、显式 h2c prior knowledge、显式 h2c Upgrade（Upgrade 模式禁请求体、重放 101 后残留字节、用 stream 1）；高层通过 SendOptions.Http2CleartextMode opt-in，默认 HTTP/1.1。
• HTTP/2 请求 body 由 body source 驱动，按连接/stream 流控和 peer MAX_FRAME_SIZE 切 DATA；请求 trailers 以 final HEADERS + END_STREAM 发送并拒绝 trailer 伪头。
• GOAWAY/RST 高层重试语义：clean GOAWAY 或 REFUSED_STREAM 表示未处理 stream 时返回 STATUS_RETRY，高层只对安全方法 fresh retry 一次，非幂等请求不自动重放。

HPACK：整数续字节 ≤5、Huffman（拒绝 >30 bit 码/EOS/非法 padding）、动态表大小更新仅限块首且 ≤协商值、header-list 大小按 name+value+32 计；编码端对 authorization/cookie/proxy-authorization 强制 Never-Indexed。

WebSocket（RFC 6455）

• ws/wss 握手；Sec-WebSocket-Accept 常量时间比对；拒绝任何 Sec-WebSocket-Extensions；子协议协商。
• 支持调用方提供 opening-handshake headers（如 Origin、Authorization、Cookie），拒绝库受控头（Host、Connection、Upgrade、Sec-WebSocket-* 等）和非法头文本。
• HTTP/1.1 Upgrade 路径客户端帧始终掩码（每帧新随机键）；RFC 8441 over HTTP/2 路径按规范发送无掩码帧；收到被掩码的服务端帧→协议错误 1002。
• wss 可通过 AllowWebSocketOverHttp2 显式 opt-in RFC 8441；默认仍保持 HTTP/1.1 Upgrade，ws:// 不隐式走 h2c。
• 分片发送：kws::SendContinuation + SendOptions{FinalFragment}，自动按帧缓冲分块；跨片增量 UTF-8 校验。
• 接收分片回调：默认聚合完整消息；显式 ReceiveOptions.DeliverFragments=true 时，ReceiveOptions.OnMessage 或返回式按 wire fragment 交付并暴露真实 finalFragment。
• 控制帧：自动 Pong（可关）、单次接收控制帧 ≤100（超限 close 1008）；文本/close payload UTF-8 校验（非法 1007）；超 MaxMessageBytes close 1009。
• close 握手：主动（发 close 后等 peer close，3s 超时）与被动（echo 后关）。

TLS 1.2（RFC 5246）/ 1.3（RFC 8446）

• 客户端只走单版本路径（1.3 在范围内优先）；无握手内自动降级——失败时分类为 VersionNegotiation 由上层显式重连 1.2。
• 下游 cipher/group/sig 分「默认启用 / 可选 / 兼容(Legacy)」三档（详见 TLS 与证书）。默认套件为 ECDHE-RSA/ECDSA 的 AES-GCM 与 ChaCha20-Poly1305 + TLS1.3 三件套；默认群 X25519/P-256/P-384/P-521；默认签名 RSA-PSS/ECDSA/Ed25519/Ed448。
• TLS1.2 强制 Extended Master Secret、安全重协商指示、CBC 必须 Encrypt-then-MAC，否则失败。
• TLS1.3：HelloRetryRequest（binder 重算）、KeyUpdate（仅在服务端请求时被动 rekey）、NewSessionTicket、record padding、signature_algorithms_cert、OCSP stapling 解析。
• 会话恢复绑定 policy 身份 + SNI + ALPN + cipher + 版本（1.2/1.3 各最多 4 条缓存）。
• 记录层：AES-GCM(1.2/1.3)、AES-CBC EtM（MAC 常量时间先验后解）、ChaCha20-Poly1305；序列号溢出保护；多项抗洪泛记录上限。

证书校验（在扩展内核栈上运行）

• 链 ≤8；有界候选路径搜索按 subject/issuer、AKI/SKI 与签名可验证性选择链，覆盖多中间与交叉签名；逐链签名验证、有效期、basic constraints/pathLen、KU（keyCertSign）、EKU serverAuth（可选）、Name Constraints、certificatePolicies、信任锚。
• 解析期拒绝重复扩展与未知 critical 扩展。
• 主机名：SAN dNSName 通配仅限单个最左标签；IP literal 只匹配 iPAddress SAN；从不回退 CN（CN 仅用于 name-constraint）；IDNA/punycode。
• 撤销：纯离线、表驱动（OCSP stapling 由调用方解析入表 + OCSP/CRL 缓存）；OnlineRequired 下查不到 → fail-closed（STATUS_TRUST_FAILURE）。
• SPKI pin：对已配置 pin 的主机强校验叶证书 SPKI；未配置 pin 的主机 fail-open。
• mTLS：私钥不入库，经 TlsClientCredential.Sign 回调签名。

密码学：SHA-1/256/384/512、HMAC、HKDF；AES-GCM（CNG）、ChaCha20-Poly1305 / AES-CCM / X25519 / X448 / FFDHE2048-8192 为内核内软件实现；NIST 曲线走 CNG ECDH；签名验证 RSA-PKCS1/RSA-PSS(salt=摘要长)/ECDSA；最小 RSA 模数 2048 位；FFDHE 公钥范围校验；密钥材料统一 RtlSecureZeroMemory 清零。

默认关闭、需显式开启

能力	开启方式 / 说明
Expect: 100-continue	SendFlagExpectContinue 显式开启
h2c prior knowledge / Upgrade	SendOptions.Http2CleartextMode 显式开启；默认不走明文 HTTP/2
WebSocket over HTTP/2	AllowWebSocketOverHttp2=true 显式开启；默认 HTTP/1.1 Upgrade
TLS1.2 RSA kx / CBC / SHA-1	TlsPolicy.Profile=CompatibilityExplicit 后分别开启 EnableTls12RsaKeyExchange、EnableTls12Cbc、EnableTls12Sha1Signatures
TLS1.3 0-RTT	连接选项 EnableEarlyData + EarlyDataReplaySafe，且 ticket 通告 max_early_data_size
TLS1.3 post-handshake client auth	EnablePostHandshakeClientAuth；开启后经 mTLS 回调签名，私钥不进入库
强撤销要求	RequireRevocationCheck；查不到调用方提供的 OCSP/CRL 数据时 fail-closed

安全拒绝 / 策略约束

这些是有意的安全或协议策略，不表示缺少实现。

行为	处理
用户手写请求 Transfer-Encoding / TE	拒绝；请求 framing 由库生成和校验
HTTP/1.1 request trailer	仅允许 chunked 请求路径
HTTP br Transfer-Encoding	拒绝；br 仅作为 Content-Encoding 支持
HTTP/2 PUSH_PROMISE	server push 禁用，收到后视为协议错误
WebSocket 服务端返回未请求扩展	拒绝，避免隐式启用 permessage-deflate 等扩展
WebSocket 握手 redirect / 401 / 407	不自动跟随或认证，返回 STATUS_NOT_SUPPORTED
TLS 1.3 到 TLS 1.2	不做握手内自动降级；只有可验证的版本协商证据才允许上层显式重连 1.2
证书主机名	IP literal 只匹配 iPAddress SAN；域名不回退 CN
HTTPS redirect 到 HTTP	默认拒绝降级

明确未实现 / 非目标

这些能力当前不提供；其中部分是明确非目标，部分只是没有做成公共能力。

能力	当前结论
HTTP 入站 request parser / server role	非目标；当前项目定位为客户端协议栈
TRACE / HTTP 管线化	非目标
RFC 9111 cache	不提供内核缓存 API
Range / 条件请求语义处理	仅普通 header 透传；不合并、不验证语义；响应 Content-Range 只读解析
完整 Accept-Encoding qvalue/content negotiation	不提供完整协商语义；默认 header 仅表达已实现 decoder 子集，调用方可覆盖
HTTP/2 priority 公共调度能力	不作为公共能力
HTTP/2 后台自动 PING 保活	不提供；调用方可显式 SendPing
WebSocket extensions（如 permessage-deflate）	非目标；不协商
WebSocket over HTTP/2 默认自动选择	当前不做；必须显式 opt-in
TLS 1.2 真重协商	非目标；兼容档仅处理安全重协商信令，不执行 renegotiation
在线 OCSP/CRL 抓取	非目标；调用方通过外部 trust/cert/revocation 数据或已缓存条目驱动强撤销判定
HTTP/3 / QUIC	非目标

实现策略和信任模型

• 传输层主路径使用 WSK；TLS、HTTP、证书校验按内核自实现路线推进。
• 密码学优先使用内核态 CNG/BCrypt；ChaCha20-Poly1305、AES-CCM、X25519、X448、FFDHE、Ed25519/Ed448 验签等由内核内软件实现补齐。
• 不把 WinHTTP、WinINet、SChannel 作为内核主路径。
• 库层不硬编码系统 CA；信任锚、CA 包、撤销缓存和 pin 由调用方显式提供。

关键默认行为

• Redirect：301/302 仅 POST→GET；303 除 HEAD 外→GET；307/308 保留方法和 body；跨源清理 Authorization/Cookie/Proxy-Authorization；拒绝 HTTPS→HTTP 降级。达到最大跳数（默认 10）时不报错，直接返回该 3xx 响应。
• Stale 重试：仅 GET/HEAD/OPTIONS，且复用连接、ReuseOrCreate、失败状态属连接关闭族/STATUS_RETRY/STATUS_IO_TIMEOUT 时，以 ForceNew 重试恰好一次。
• 连接池：close-delimited 与 101 响应不回池；NoPool 从不挤掉活跃连接，ForceNew/ReuseOrCreate 会驱逐空闲槽。
• IRQL：同步 HTTP/WS/TLS/证书路径要求 PASSIVE_LEVEL，否则 STATUS_INVALID_DEVICE_REQUEST/STATUS_INVALID_DEVICE_STATE。

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English

Capability Matrix

This page is grounded in the actual src/KernelHttpLib/ implementation.

HTTP/1.1: Content-Length, builder-generated chunked, and true streaming request bodies (BodyCreateStream / KhHttpRequestSetBodySource; caller Transfer-Encoding/TE are rejected; Trailer is allowed only with chunked request trailers); request trailers via KhHttpRequestAddTrailer / khttp::RequestAddTrailer; explicit Expect: 100-continue via SendFlagExpectContinue with 100/final/417/timeout/disconnect branches covered; HTTPS proxy uses CONNECT and plaintext HTTP over proxy uses absolute-form targets; response parsing accepts only HTTP/1.0–1.1, header line ≤8 KiB, section ≤64 KiB, ≤200 headers, rejects obs-fold, rejects duplicate Content-Length and TE+CL conflict; no-body for 1xx/204/205/304 and HEAD; chunked ≤8192 chunks with strict extension grammar and forbidden-trailer rejection; read-only 206 / Content-Range parsing; Content-Encoding gzip (CRC32/ISIZE verified), deflate (zlib autodetect + Adler-32, via kernel RtlDecompressBufferEx with runtime probe), br (bundled Brotli), compress (full LZW), identity, up to 2 codings reverse-decoded; decompression-bomb guard 64× per-step; 1xx skipping; redirects; keep-alive pooling.

HTTP/2: preface + SETTINGS (7 settings including ENABLE_CONNECT_PROTOCOL, ACK sent immediately, not awaited), SETTINGS validation (ENABLE_PUSH!=0 rejected, ENABLE_CONNECT_PROTOCOL must be 0/1, window/frame bounds), CONTINUATION flood guards (64 / 4 empty), active-stream table with two-stage BeginRequest / ReceiveResponse(streamId), interleaved frame dispatch by stream id, high-level khttp pooled multi-stream reuse, connection + per-stream flow control with half-window WINDOW_UPDATE threshold, streaming request DATA from body sources, request trailers as final HEADERS + END_STREAM, GOAWAY/RST retry semantics surfaced as STATUS_RETRY for unprocessed safe-method retries, 1xx interim handling, PUSH_PROMISE always a protocol error, RFC 8441 extended CONNECT tunnel primitives, three modes (TLS-ALPN h2 / explicit h2c prior-knowledge / explicit h2c upgrade via SendOptions.Http2CleartextMode — upgrade forbids a body, replays post-101 bytes, uses stream 1). HPACK: continuation-byte ≤5, Huffman (rejects >30-bit codes/EOS/bad padding), table-size-update only at block start, never-indexed forced for authorization/cookie/proxy-authorization.

WebSocket: handshake with constant-time accept comparison, caller-supplied opening headers with controlled-header rejection, rejects any Sec-WebSocket-Extensions, subprotocol negotiation; HTTP/1.1 client frames are masked, RFC 8441 over HTTP/2 frames are unmasked as required (masked server frame → 1002); explicit opt-in high-level wss over HTTP/2 via AllowWebSocketOverHttp2; fragment send (kws::SendContinuation + FinalFragment) with incremental cross-fragment UTF-8 validation; default aggregated whole-message receive or explicit wire-fragment delivery via ReceiveOptions.DeliverFragments=true and ReceiveOptions.OnMessage; auto-Pong (toggleable), ≤100 control frames per receive (1008), UTF-8 validation (1007), max-message (1009); active and passive close handshakes; opening-handshake 3xx/401/407 returns STATUS_NOT_SUPPORTED rather than following redirect/auth challenges.

TLS 1.2/1.3: single-version path (no in-handshake fallback — failures classified as VersionNegotiation for an explicit caller retry at 1.2); cipher/group/sig split into default / optional / legacy; TLS1.2 enforces EMS + secure-reneg indication + Encrypt-then-MAC for CBC; TLS1.3 HelloRetryRequest, reactive-only KeyUpdate, NewSessionTicket, record padding, signature_algorithms_cert, OCSP stapling parse; resumption bound to policy identity + SNI + ALPN + cipher + version. Certificate validation (on an expanded kernel stack): chain ≤8 with bounded candidate path search, subject/issuer plus AKI/SKI matching, cross-signed intermediates, signature/validity/basic-constraints/pathLen/KU/EKU/name-constraints/cert-policies/trust-anchor; rejects duplicate and unknown-critical extensions; hostname match with single-label wildcard, IP literals match iPAddress SAN only, never falls back to CN; revocation offline + table-driven, fail-closed when required-but-absent; SPKI pinning (fail-open for un-pinned hosts); mTLS via caller Sign callback (private key never enters the library). Crypto: ChaCha20-Poly1305/AES-CCM/X25519/X448/FFDHE/Ed25519/Ed448 verification are in-kernel software; min RSA modulus 2048.

Default-Off Opt-Ins

Capability	How it is enabled
Expect: 100-continue	SendFlagExpectContinue
h2c prior knowledge / Upgrade	SendOptions.Http2CleartextMode
WebSocket over HTTP/2	AllowWebSocketOverHttp2=true
TLS 1.2 RSA-kx / CBC / SHA-1	TlsPolicy.Profile=CompatibilityExplicit plus the matching compatibility switch
TLS 1.3 0-RTT	EnableEarlyData + EarlyDataReplaySafe, with a ticket that advertises max_early_data_size
TLS 1.3 post-handshake client auth	EnablePostHandshakeClientAuth; signatures use the mTLS callback and private keys never enter the library

Security Refusals / Policy Constraints

These are deliberate security or protocol choices, not missing implementation.

Behavior	Handling
Caller-supplied request Transfer-Encoding / TE	Rejected; request framing is generated and validated by the library
HTTP/1.1 request trailers	Allowed only on the chunked request path
HTTP br Transfer-Encoding	Rejected; br is supported only as Content-Encoding
HTTP/2 PUSH_PROMISE	Server push is disabled and treated as a protocol error
Unexpected WebSocket extensions	Rejected to avoid implicitly enabling extensions such as permessage-deflate
WebSocket handshake redirect / 401 / 407	Not followed automatically; returns STATUS_NOT_SUPPORTED
TLS 1.3 to TLS 1.2	No in-handshake automatic fallback; only verified version-negotiation evidence allows an explicit caller retry at 1.2
Certificate hostname matching	IP literals match iPAddress SAN only; DNS names never fall back to CN
HTTPS redirect to HTTP	Rejected by default

Missing / Explicit Non-Goals

These capabilities are not provided today; some are explicit non-goals, while others are simply not public capabilities.

Capability	Current conclusion
HTTP inbound request parser / server role	Non-goal; this project is a client protocol stack
TRACE / HTTP pipelining	Non-goal
RFC 9111 cache	No kernel cache API is provided
Range / conditional request semantics	Pass-through headers only; no semantic merge or validation; response Content-Range is read-only
Full Accept-Encoding qvalue/content negotiation	Not provided; default header only describes the implemented decoder subset and callers may override it
HTTP/2 priority as public scheduling	Not exposed as a public capability
HTTP/2 background automatic PING keepalive	Not provided; callers can use explicit SendPing
WebSocket extensions such as permessage-deflate	Non-goal; not negotiated
Automatic default WebSocket over HTTP/2 selection	Not done today; explicit opt-in is required
TLS 1.2 true renegotiation	Non-goal; compatibility profile handles secure renegotiation signaling but does not perform renegotiation
Online OCSP/CRL fetching	Non-goal; callers provide external trust/certificate/revocation data or cached entries
HTTP/3 / QUIC	Non-goal

Implementation Strategy and Trust Model

• The transport main path uses WSK; TLS, HTTP, and certificate validation are implemented in the kernel path.
• Cryptography uses kernel-mode CNG/BCrypt first. ChaCha20-Poly1305, AES-CCM, X25519, X448, FFDHE, and Ed25519/Ed448 verification are filled in by in-kernel software implementations.
• WinHTTP, WinINet, and SChannel are not used as the kernel main path.
• The library does not hard-code system CAs; callers explicitly provide trust anchors, CA bundles, revocation cache entries, and pins.

See Roadmap.