feat(storage): support signed read options and local byte ranges

2026-09-30 22:44:54 +08:00
parent 01a03149f9
commit f0c62152d7
29 changed files with 1395 additions and 30 deletions
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,10 @@
+# v0.29.0-preview
+
+- 新增可选 `storage.ReadPresigner` / `ReadOptions` / `ReadLink`，签名读取可选择 inline/attachment、显示文件名、MIME 类型，返回签名内的实际到期时间。原 Store/Presigner 和旧下载链接兼容，TTL 上限仍为一小时。
+- Local、S3/R2、OSS 均实现；全部选项参与本地 HMAC 或云端原生 SDK 签名，标准编码中文文件名并拒绝非法响应头。
+- 本地读取支持 GET/HEAD、单段与多段 Range、206/416、条件请求，按文件内容真实长度处理，流式读取不暴露本地元数据。顺序读取的第三方 Store 保持完整 200 回退。
+- 补充通用 PDF 运行示例、篡改与到期回归、OSS V1/V4 签名校验、真实隔离 MinIO 验证和远程安装检查；不引入业务模型或第三方依赖。
+
 # v0.28.2-preview

 - 修复响应 DTO 的自引用/相互引用生成，支持 slice、pointer、map；OpenAPI 使用命名组件与循环引用，保留约束、描述、示例及 scalar 输出 schema。
--- a/DEVELOPMENT.md
+++ b/DEVELOPMENT.md
@@ -1,4 +1,4 @@
-# 通用业务开发指南（v0.28.2-preview）
+# 通用业务开发指南（v0.29.0-preview）

 从 [README](README.md) 创建服务后，业务主要维护 `.api`、配置、`svc.Init`、Logic、Repository 和项目中间件。本页说明通用接入能力；字段、错误码、权限、表结构和事务边界都由项目定义。

@@ -225,7 +225,7 @@ go-omni workspace check --file omni.workspace.json

 ### 混合 API 与通用工程

-v0.28.2-preview 起，workspace 支持在同一份清单中管理 API、通用工程，也支持仅包含通用工程的工作区：
+v0.29.0-preview 起，workspace 支持在同一份清单中管理 API、通用工程，也支持仅包含通用工程的工作区：

 ```json
 {
--- a/PROGRAM.md
+++ b/PROGRAM.md
@@ -5,7 +5,7 @@
 ## 创建与运行

 ```sh
-go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.28.2-preview
+go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.29.0-preview
 go-omni project new demo --module example.com/demo
 cd demo
 go mod tidy
@@ -78,4 +78,4 @@ go test ./...

 check 检查模板漂移和必要文件，不检查业务正确性，也不能替代 Go 编译与测试。新的模板版本会重新生成受管文件；不自动合并项目所有文件或更新 go.mod。未知的新清单版本会要求使用兼容 CLI。

-原有 `new` / `api new` 及 API 工程行为保留。通用工程使用自己的清单和命令，不能交给 `api generate` 或 `add` 转换；新增业务包直接写普通 Go。从 v0.28.2-preview 起，`workspace generate/check` 可以同时处理 API 与通用工程。清单可填写 `kind: api | project`，省略时按生成清单识别；format 对通用工程显示 SKIP。见 [完整混合示例](examples/mixedWorkspace/README.md)。各 module 仍独立，workspace 命令不维护 go.work 或模块依赖。
+原有 `new` / `api new` 及 API 工程行为保留。通用工程使用自己的清单和命令，不能交给 `api generate` 或 `add` 转换；新增业务包直接写普通 Go。从 v0.29.0-preview 起，`workspace generate/check` 可以同时处理 API 与通用工程。清单可填写 `kind: api | project`，省略时按生成清单识别；format 对通用工程显示 SKIP。见 [完整混合示例](examples/mixedWorkspace/README.md)。各 module 仍独立，workspace 命令不维护 go.work 或模块依赖。
--- a/README.md
+++ b/README.md
@@ -2,6 +2,8 @@

 GoOmni 是面向多个项目复用的 Go 基础框架。通用工程使用 `project new` 生成配置、日志、依赖装配、生命周期和普通 Go 运行入口；需要 HTTP 接口时可选择 `.api` 工程生成，也可以在已有项目中按需引入独立模块。运行方式、业务类型和外部依赖由项目决定。

+**v0.29 改动**：通用签名读取新增 inline/attachment、中文显示文件名、可选 Content-Type 与实际到期时间；Local、S3/R2、OSS 使用同一接口，原下载接口兼容。本地支持 HEAD、Range、206/416，所有响应选项参与签名。见 [存储说明](storage/README.md#签名预览与下载)及[可运行 PDF 示例](examples/signedRead/README.md)。
+
 **v0.28.2 改动**：API 响应 DTO 支持 `Children []Node`、`Next *Node`、递归 map 和相互引用，生成强类型 Go 字段及有限的 OpenAPI `$ref` 图。字段约束、示例校验、生成与漂移检查继续有效；请求递归和非法值递归仍会报错。见 [可运行示例](examples/recursiveResponse/README.md)与[接入说明](DEVELOPMENT.md#递归响应-dto)。

 **v0.28.1 改动**：`workspace generate/check` 支持 API 与通用工程混合处理，可选 `kind: api | project`，省略时按生成清单识别。`format` 对通用工程显示跳过；检查只读，生成前统一预检。见 [混合工作区示例](examples/mixedWorkspace/README.md)。
@@ -10,9 +12,9 @@ GoOmni 是面向多个项目复用的 Go 基础框架。通用工程使用 `proj

 **v0.27 改动**：统一三种内置服务实现的默认/路由/硬请求体限额，配置冲突在启动前报错；停机以处理函数实际退出为资源清理前提，超时仍有请求时保留共享依赖。见 [HTTP 策略](transport/README.md#统一请求体限额)、[停机规则](lifecycle/README.md#http-请求与依赖的关闭屏障)和[可运行示例](examples/httpSafety/README.md)。

-**v0.26 改动**：通用 [i18n](i18n/README.md)，提供独立词典、语言匹配、回退、命名参数/条件/复数、可选 HTTP 与错误适配、检查/导出 CLI 及前端运行时。文案由项目维护；[完整示例](examples/i18n/README.md)可直接运行。CLI 与框架使用同版 v0.28.2-preview。同时修复 Go 1.22 下请求体限额错误的识别。
+**v0.26 改动**：通用 [i18n](i18n/README.md)，提供独立词典、语言匹配、回退、命名参数/条件/复数、可选 HTTP 与错误适配、检查/导出 CLI 及前端运行时。文案由项目维护；[完整示例](examples/i18n/README.md)可直接运行。CLI 与框架使用同版 v0.29.0-preview。同时修复 Go 1.22 下请求体限额错误的识别。

-**从这份 README 开始接入。** 当前版本 **`v0.28.2-preview`**，通用工程采用根目录入口和 `config / svc / run`；API 工程使用 `config / svc / logic / handler`。可以固定版本开展业务接入；文件维护边界和已有服务迁移步骤见 [项目指南](PROJECT.md)，版本变化与验收见 [发布说明](RELEASE.md)。
+**从这份 README 开始接入。** 当前版本 **`v0.29.0-preview`**，通用工程采用根目录入口和 `config / svc / run`；API 工程使用 `config / svc / logic / handler`。可以固定版本开展业务接入；文件维护边界和已有服务迁移步骤见 [项目指南](PROJECT.md)，版本变化与验收见 [发布说明](RELEASE.md)。

 **v0.25 改动**：`database.InTx` 返回可识别的事务阶段与结果，保留业务/驱动及回滚错误链；提交报错保守标记为结果不确定，不等同于已回滚。[使用规则](database/README.md#事务阶段与结果)、[可运行故障示例](examples/transactions/README.md)。

@@ -68,7 +70,7 @@ Go **1.22+**。框架不依赖 Gin，默认使用标准库网络层，提供可
 | 请求追踪、访问日志、恢复、限流、幂等、超时 | `app.Use(...)` 按需组合 middleware；跨副本选择 Redis 实现 | [模块说明与限制](MODULES.md#请求追踪与基础指标)、[分布式实现](ADVANCED.md#分布式限流与幂等) |
 | 本地后台任务与调度 | `task.New`、Submit、Every；有界队列、排空关闭 | [task 示例与生命周期](MODULES.md#后台执行task) |
 | 持久队列 | 业务使用 Publisher / Consumer；Redis Streams 提供至少一次交付 | [队列初始化/消费示例](ADVANCED.md#可靠队列) |
-| 文件存储、直传、云端分片 | Store 的 Put/Get/Delete；Local、S3/R2、OSS 按配置装配；扩展接口提供分片续传 | [存储接口与完整例子](storage/README.md)、[本地存储服务](examples/platform/README.md) |
+| 文件存储、签名预览/下载、直传与云端分片 | Store 的 Put/Get/Delete；ReadPresigner 签名响应选项；Local、S3/R2、OSS 按配置装配 | [存储接口与完整例子](storage/README.md)、[本地存储服务](examples/platform/README.md) |
 | 日志关联、指标与链路 | `metrics.New().Middleware()`；telemetry 注入 OTel exporter/reader | [基础指标](MODULES.md#请求追踪与基础指标)、[OTel 用法](ADVANCED.md#熔断与观测)、[完整接入](examples/platform/main.go) |
 | 审计与分页 | `audit.New` 注入 Sink/白名单；`pagination.Parse` / `NewResult` | [解释与调用例子](ADVANCED.md#迁移审计与分页) |
 | 可选结构转换与深拷贝 | `copyx.Copy` / `Clone` / `New`；`Check[S,T]` 预检类型，Go converter 处理差异 | [下方示例](#可选结构转换与深拷贝)、[完整 copyx 指南](COPY.md)、[可运行代码](examples/copying) |
@@ -77,7 +79,7 @@ Go **1.22+**。框架不依赖 Gin，默认使用标准库网络层，提供可
 ## 通用工程快速开始

 ```sh
-go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.28.2-preview
+go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.29.0-preview
 go-omni project new demo --module example.com/demo
 cd demo
 go mod tidy
@@ -182,7 +184,7 @@ module 地址是 `git.yuntuo.hk/k2safe/go-omni`。先确保本机 Go 和 Git 可

 ```sh
 export GOPRIVATE="$(go env GOPRIVATE),git.yuntuo.hk"
-go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.28.2-preview
+go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.29.0-preview
 export PATH="$(go env GOPATH)/bin:$PATH"
 go-omni --help
 ```
@@ -339,7 +341,7 @@ go-omni new --api catalog.api \
 在业务项目的 **go.mod 所在目录**执行：

 ```sh
-go get git.yuntuo.hk/k2safe/go-omni@v0.28.2-preview
+go get git.yuntuo.hk/k2safe/go-omni@v0.29.0-preview
 ```

 已有项目可直接复用现有目录、Service、Repository 和数据库连接，先选择一个接口接入。也可以只用 `logx`、`storage` 等包，暂时保留原来的 HTTP 框架。希望入口和 HTTP 接入都交给生成器的项目，按 [已有服务接入步骤](PROJECT.md#已有服务接入步骤) 在新目录生成后迁入业务代码。
@@ -670,7 +672,7 @@ go test ./...

 `main.go`、`Gen.go`、`docs/openapi.json` 和 manifest 由生成器管理，手动修改会报告冲突。Logic、Repository、中间件实现、配置和依赖装配属于项目，重复生成保留手写内容。契约变化会提示受影响的 Logic 文件和 DTO 字段，明确的签名错误会给出原签名与期望签名；生成后 `--check` 仍能检出未修复的问题。将 `.api`、`omni.gen.json`、生成文件和 `.goOmni/apiManifest.json` 一起提交，CI 同时运行 `generate --check` 与 `go test ./...`。详见 [契约变更提示与检查边界](PROJECT.md#契约变更提示)。

-CLI 与业务 module 固定使用 `v0.28.2-preview`。v0.21 及更早项目先按 [配置迁移](CONFIG.md#v022-迁移旧模式已移除) 整理旧标签、文件与 Load，再升级依赖与 CLI 并重新生成，框架维护的 main/runtimeGen 自动更新；v0.13 及更早项目按 [升级预览](DEVELOPMENT.md#v013-项目升级) 处理，不直接覆盖手写入口或业务文件。使用过旧 mapping 的项目必须先完成 [移除迁移](COPY.md#从旧-mapping-迁移)，旧配置或旧生成文件会阻止生成。升级后执行生成检查与业务回归。版本变化、迁移边界和验收记录见 [发布说明](RELEASE.md)。
+CLI 与业务 module 固定使用 `v0.29.0-preview`。v0.21 及更早项目先按 [配置迁移](CONFIG.md#v022-迁移旧模式已移除) 整理旧标签、文件与 Load，再升级依赖与 CLI 并重新生成，框架维护的 main/runtimeGen 自动更新；v0.13 及更早项目按 [升级预览](DEVELOPMENT.md#v013-项目升级) 处理，不直接覆盖手写入口或业务文件。使用过旧 mapping 的项目必须先完成 [移除迁移](COPY.md#从旧-mapping-迁移)，旧配置或旧生成文件会阻止生成。升级后执行生成检查与业务回归。版本变化、迁移边界和验收记录见 [发布说明](RELEASE.md)。

 ## 按需深入

--- a/RELEASE.md
+++ b/RELEASE.md
@@ -1,3 +1,19 @@
+# v0.29.0-preview
+
+新增通用签名读取选项：预览或下载、显示文件名和 MIME 类型，由调用方选择。`PresignGetWithOptions` 返回 URL 与签名内的到期时间；原 `PresignGet` 默认下载、第三方原有接口和旧本地链接继续兼容。有效期仍是 1 秒到 1 小时，不增加撤销或业务分享机制。
+
+Local、S3/R2、OSS 使用同一接口，所有选项参与签名。中文文件名采用标准编码，拒绝 CR/LF 等非法头内容。本地支持 HEAD、单段/多段 Range、206/416 与条件请求，按真实内容范围流式输出；过期与篡改在读取文件之前拒绝。
+
+```sh
+go get git.yuntuo.hk/k2safe/go-omni@v0.29.0-preview
+go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.29.0-preview
+go test ./...
+```
+
+[接口与接入边界](storage/README.md#签名预览与下载)、[完整示例](examples/signedRead/README.md)、[验收记录](reports/signedReadAcceptance.md)。生成模板最低运行时版本不变；使用新读取接口需要升级框架依赖。OSS 默认域名可能强制下载，应在 SDK 签名前配置所需域名；OSS/R2 云账号尚未实测，部署方须按实际桶、域名和浏览器验收。
+
+---
+
 # v0.28.2-preview

 修复 `.api` 响应 DTO 自引用与相互引用的生成限制。`Children []Node`、`Next *Node`、`map[string]Node` 保留强类型，响应文档使用有限的命名组件与 `$ref`；可空引用、字段描述、示例、约束和 scalar 输出类型保持准确。框架不引入业务模型。
--- a/cmd/go-omni/README.md
+++ b/cmd/go-omni/README.md
@@ -20,7 +20,7 @@ API 新项目采用根目录 `main.go` 与 `internal/config、svc、logic、hand

 ```sh
 # 仓库读取权限与 PATH 配置见根目录 README
-go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.28.2-preview
+go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.29.0-preview
 go-omni new --module example.com/hello ./hello

 # 从自己的契约生成；service.api 及其相对 import 文件需要在本地存在
@@ -57,14 +57,14 @@ main、Gen.go、OpenAPI 和 manifest 由生成器维护；业务文件按字节

 ## 版本与迁移

-CLI 与框架依赖固定使用 v0.28.2-preview。远程安装的 CLI 默认把自身版本写入 go.mod，不添加本地 replace；`--framework-version` 可显式指定已发布的兼容版本。仅在开发框架源码时使用本地替换：
+CLI 与框架依赖固定使用 v0.29.0-preview。远程安装的 CLI 默认把自身版本写入 go.mod，不添加本地 replace；`--framework-version` 可显式指定已发布的兼容版本。仅在开发框架源码时使用本地替换：

 ```sh
 # 在 go-omni 源码仓库中执行
 go run ./cmd/go-omni new --module example.com/hello --framework-dir . ../hello
 ```

-当前模板与依赖以 v0.28.2-preview 为基线，继续使用 manifest v2；GORM 可选适配器从 v0.14.1-preview 提供。已有项目使用 [定点升级与预览](../../DEVELOPMENT.md#v013-项目升级)：原始模板可自动替换，含业务修改的基础文件按预览合并；通用清理由 Runtime 负责。独立工具命令不会被删除。受管理项目通过 `.api` 模块导入增加业务，不使用旧 `add` 命令的手动路由装配。
+当前模板与依赖以 v0.29.0-preview 为基线，继续使用 manifest v2；GORM 可选适配器从 v0.14.1-preview 提供。已有项目使用 [定点升级与预览](../../DEVELOPMENT.md#v013-项目升级)：原始模板可自动替换，含业务修改的基础文件按预览合并；通用清理由 Runtime 负责。独立工具命令不会被删除。受管理项目通过 `.api` 模块导入增加业务，不使用旧 `add` 命令的手动路由装配。

 ## 数据库迁移命令

--- a/cmd/go-omni/apigen/generate.go
+++ b/cmd/go-omni/apigen/generate.go
@@ -23,7 +23,7 @@ const frameworkModule = "git.yuntuo.hk/k2safe/go-omni"

 // Runtime-only releases need not raise the managed template compatibility floor.
 const minimumVersion = "v0.22.0-preview"
-const currentVersion = "v0.28.2-preview"
+const currentVersion = "v0.29.0-preview"
 const generatedHeader = "// Code generated by go-omni api. DO NOT EDIT.\n"

 type Options struct {
--- a/cmd/go-omni/projectgen/generate.go
+++ b/cmd/go-omni/projectgen/generate.go
@@ -25,7 +25,7 @@ import (
 )

 const frameworkModule = "git.yuntuo.hk/k2safe/go-omni"
-const currentVersion = "v0.28.2-preview"
+const currentVersion = "v0.29.0-preview"
 const minimumVersion = "v0.28.0-preview"
 const manifestPath = ".goOmni/projectManifest.json"
 const lockPath = ".goOmni/project.lock"
--- a/cmd/go-omni/scaffold/version.go
+++ b/cmd/go-omni/scaffold/version.go
@@ -10,7 +10,7 @@ const frameworkModule = "git.yuntuo.hk/k2safe/go-omni"
 // Source builds can carry an unpublished VCS version (including +dirty).
 // Keep this fallback in sync with the next release; installed CLIs use their
 // downloaded module version, which also has a module checksum.
-const defaultFrameworkVersion = "v0.28.2-preview"
+const defaultFrameworkVersion = "v0.29.0-preview"

 // This target is not a claim that the release already exists. Source users
 // select a local framework checkout until the module templates are published.
--- a/examples/mixedWorkspace/README.md
+++ b/examples/mixedWorkspace/README.md
@@ -1,11 +1,11 @@
 # API 与通用工程混合工作区

-本例只定义生成工程的类型与目录，不包含业务模型、外部服务或特定调度方式。使用 v0.28.2-preview 或更新版本 CLI。
+本例只定义生成工程的类型与目录，不包含业务模型、外部服务或特定调度方式。使用 v0.29.0-preview 或更新版本 CLI。

 下面从一个空目录创建两个独立 Go module；API 工程来自 API 模板，通用工程默认不监听端口。

 ```sh
-go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.28.2-preview
+go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.29.0-preview
 mkdir mixed-demo
 cd mixed-demo
 go-omni api new apps/interface --module example.com/interface
--- a/examples/recursiveResponse/README.md
+++ b/examples/recursiveResponse/README.md
@@ -5,7 +5,7 @@
 在 go-omni 仓库根目录执行（新建独立临时目录）：

 ```sh
-go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.28.2-preview
+go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.29.0-preview
 example_dir="$(mktemp -d)/recursive"
 go-omni api generate --api examples/recursiveResponse/service.api --dir "$example_dir" --module example.com/recursive
 # 以下文件仅是本次新生成示例的占位实现，替换为示例自身维护的逻辑。
--- a/examples/signedRead/README.md
+++ b/examples/signedRead/README.md
@@ -0,0 +1,15 @@
+# 通用签名读取
+
+```sh
+go run ./examples/signedRead
+# 或执行真实 HTTP 检查并退出
+go run ./examples/signedRead -check
+```
+
+示例自动创建临时私有存储、一页 PDF 和随机签名密钥，监听随机 loopback 端口。打开终端显示的首页，可预览或下载带中文文件名的 PDF；两条链接从签发起 30 分钟有效。首页显示签名内的实际到期时间，不会通过刷新延长链接；重启会生成新的文件和密钥。Ctrl+C 清理临时目录。
+
+示例使用 `storage.ReadPresigner` 对应的 `PresignGetWithOptions` 能力，本地 `Signer` 与 S3/R2、OSS 适配器采用同一组 `ReadOptions`。省略 Disposition 默认 attachment，inline 请求浏览器内联展示；实际展示仍由浏览器设置和文件格式支持决定。原 `PresignGet` 接口与既有下载链接保持兼容。
+
+本地支持 GET、HEAD、Range、206/416，响应范围只包含文件内容。云端由原生存储地址响应，GET 签名不通用于 HEAD；OSS 默认域名可能强制下载，应在 SDK 签名前配置自己的域名。详见 [存储接入说明](../../storage/README.md#签名预览与下载)。
+
+这只是回环地址上的固定测试文件演示。实际项目先检查权限，再签发指定对象的链接；配置公开签名入口，不能从请求 Host 或转发头猜测。文件路径、权限、审计和页面状态由项目维护。不要记录 URL 查询参数，不公开存储目录。链接到期仅阻止后续读取，不收回已获得的内容；重新签发不会撤销旧链接。
--- a/examples/signedRead/main.go
+++ b/examples/signedRead/main.go
@@ -0,0 +1,183 @@
+// signedRead is an offline, loopback-only preview/download demonstration.
+package main
+
+import (
+	"bytes"
+	"context"
+	"crypto/rand"
+	"errors"
+	"flag"
+	"fmt"
+	"html/template"
+	"io"
+	"mime"
+	"net"
+	"net/http"
+	"os"
+	"os/signal"
+	"strconv"
+	"time"
+
+	"git.yuntuo.hk/k2safe/go-omni/storage"
+	"git.yuntuo.hk/k2safe/go-omni/storage/local"
+)
+
+func main() {
+	check := flag.Bool("check", false, "run HTTP checks and exit")
+	flag.Parse()
+	if err := run(*check); err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+}
+
+func run(check bool) error {
+	root, err := os.MkdirTemp("", "go-omni-signed-read-")
+	if err != nil {
+		return err
+	}
+	defer os.RemoveAll(root)
+	files, err := local.New(root, 1<<20)
+	if err != nil {
+		return err
+	}
+	content := samplePDF()
+	if _, err = files.Put(context.Background(), "sample.pdf", bytes.NewReader(content), int64(len(content)), "application/pdf"); err != nil {
+		return err
+	}
+	listener, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		return err
+	}
+	defer listener.Close()
+	baseURL := "http://" + listener.Addr().String()
+	secret := make([]byte, 32)
+	if _, err = rand.Read(secret); err != nil {
+		return err
+	}
+	signer, err := storage.NewSigner(files, baseURL+"/file", secret)
+	if err != nil {
+		return err
+	}
+	// Production applications authorize the caller before this operation. The
+	// sample intentionally exposes only a generated fixture on loopback.
+	preview, err := signer.PresignGetWithOptions(context.Background(), "sample.pdf", 30*time.Minute, storage.ReadOptions{
+		Disposition: storage.DispositionInline, FileName: "示例报告.pdf", ContentType: "application/pdf",
+	})
+	if err != nil {
+		return err
+	}
+	download, err := signer.PresignGetWithOptions(context.Background(), "sample.pdf", 30*time.Minute, storage.ReadOptions{FileName: "示例报告.pdf"})
+	if err != nil {
+		return err
+	}
+	page := template.Must(template.New("page").Parse(`<!doctype html><html lang="zh-CN"><meta charset="utf-8"><title>Signed read example</title>
+<body><h1>文件预览与下载</h1><p><a href="{{.Preview.URL}}">打开示例 PDF</a> · <a href="{{.Download.URL}}">下载示例 PDF</a></p>
+<p>链接到期时间：{{.Preview.ExpiresAt}}</p><p>只读演示：无数据库、业务身份或公开磁盘目录。</p></body></html>`))
+	mux := http.NewServeMux()
+	mux.Handle("/file", signer)
+	mux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path != "/" || r.Method != http.MethodGet {
+			http.NotFound(w, r)
+			return
+		}
+		w.Header().Set("Content-Type", "text/html; charset=utf-8")
+		w.Header().Set("Cache-Control", "private, no-store")
+		w.Header().Set("Referrer-Policy", "no-referrer")
+		_ = page.Execute(w, struct{ Preview, Download storage.ReadLink }{preview, download})
+	})
+	server := &http.Server{Handler: mux, ReadHeaderTimeout: 5 * time.Second, IdleTimeout: 30 * time.Second}
+	done := make(chan error, 1)
+	go func() { done <- server.Serve(listener) }()
+	defer server.Close()
+	if check {
+		if err := checkHTTP(preview, download, content); err != nil {
+			return err
+		}
+		fmt.Println("signed read: PDF preview, Chinese filename, download, HEAD and Range passed")
+		return nil
+	}
+	// Never print signed URLs or enable request logging containing query strings.
+	fmt.Println("Open " + baseURL + " (Ctrl+C to stop)")
+	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt)
+	defer stop()
+	select {
+	case err := <-done:
+		if errors.Is(err, http.ErrServerClosed) {
+			return nil
+		}
+		return err
+	case <-ctx.Done():
+		shutdown, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+		defer cancel()
+		return server.Shutdown(shutdown)
+	}
+}
+
+func checkHTTP(preview, download storage.ReadLink, content []byte) error {
+	client := &http.Client{Timeout: 5 * time.Second}
+	for _, tc := range []struct {
+		link                      storage.ReadLink
+		method, span, disposition string
+		status                    int
+		body                      []byte
+	}{
+		{preview, "GET", "", "inline", 200, content},
+		{preview, "HEAD", "", "inline", 200, nil},
+		{preview, "GET", "bytes=0-7", "inline", 206, content[:8]},
+		{download, "GET", "", "attachment", 200, content},
+	} {
+		req, err := http.NewRequest(tc.method, tc.link.URL, nil)
+		if err != nil {
+			return errors.New("invalid example link")
+		}
+		if tc.span != "" {
+			req.Header.Set("Range", tc.span)
+		}
+		response, err := client.Do(req)
+		if err != nil {
+			return errors.New("example request failed")
+		}
+		body, err := io.ReadAll(response.Body)
+		response.Body.Close()
+		kind, params, headerErr := mime.ParseMediaType(response.Header.Get("Content-Disposition"))
+		if err != nil || headerErr != nil || response.StatusCode != tc.status || !bytes.Equal(body, tc.body) || kind != tc.disposition || params["filename"] != "示例报告.pdf" || response.Header.Get("Content-Type") != "application/pdf" {
+			return errors.New("example response did not match signed options")
+		}
+		size := len(tc.body)
+		if tc.method == "HEAD" {
+			size = len(content)
+		}
+		if response.Header.Get("Content-Length") != strconv.Itoa(size) || response.Header.Get("Cache-Control") != "private, no-store" {
+			return errors.New("example size or cache policy mismatch")
+		}
+	}
+	return nil
+}
+
+// A complete, single-page PDF with a real cross-reference table. No generator
+// dependency or business document is needed for this example.
+func samplePDF() []byte {
+	stream := "BT /F1 24 Tf 72 720 Td (go-omni signed read) Tj ET\n"
+	objects := []string{
+		"<< /Type /Catalog /Pages 2 0 R >>",
+		"<< /Type /Pages /Kids [3 0 R] /Count 1 >>",
+		"<< /Type /Page /Parent 2 0 R /MediaBox [0 0 612 792] /Resources << /Font << /F1 4 0 R >> >> /Contents 5 0 R >>",
+		"<< /Type /Font /Subtype /Type1 /BaseFont /Helvetica >>",
+		fmt.Sprintf("<< /Length %d >>\nstream\n%sendstream", len(stream), stream),
+	}
+	var pdf bytes.Buffer
+	pdf.WriteString("%PDF-1.4\n")
+	offsets := []int{0}
+	for i, object := range objects {
+		offsets = append(offsets, pdf.Len())
+		fmt.Fprintf(&pdf, "%d 0 obj\n%s\nendobj\n", i+1, object)
+	}
+	xref := pdf.Len()
+	fmt.Fprintf(&pdf, "xref\n0 %d\n0000000000 65535 f \n", len(offsets))
+	for _, offset := range offsets[1:] {
+		fmt.Fprintf(&pdf, "%010d 00000 n \n", offset)
+	}
+	fmt.Fprintf(&pdf, "trailer\n<< /Size %d /Root 1 0 R >>\nstartxref\n%d\n%%%%EOF\n", len(offsets), xref)
+	return pdf.Bytes()
+}
--- a/examples/signedRead/main_test.go
+++ b/examples/signedRead/main_test.go
@@ -0,0 +1,9 @@
+package main
+
+import "testing"
+
+func TestSignedReadHTTP(t *testing.T) {
+	if err := run(true); err != nil {
+		t.Fatal(err)
+	}
+}
--- a/reports/signedReadAcceptance.md
+++ b/reports/signedReadAcceptance.md
@@ -0,0 +1,33 @@
+# v0.29.0 通用签名读取验收
+
+范围：Local、S3/R2、OSS 的签名读取选项和本地范围读取。接口不包含业务身份、租户、分享记录、数据库、撤销或固定有效期。旧 Presigner、旧本地链接和默认下载行为兼容。
+
+## 本地回归
+
+2026-09-30，macOS arm64，Go 1.27.1：
+
+- `GO_OMNI_SCAFFOLD_INTEGRATION=1 go test -race -count=1 ./...`：57 个测试包通过，apigen 集成包 123.143 秒。
+- `GOTOOLCHAIN=go1.22.12 GO_OMNI_SCAFFOLD_INTEGRATION=1 go test -count=1 ./...`：57 个测试包通过，apigen 集成包 113.212 秒。
+- `go vet ./...`、`go build ./...`、`git diff --check`：通过。
+- `go run ./examples/signedRead -check`：真实回环 HTTP 预览、中文文件名、下载、HEAD、Range 通过。
+- `python3 scripts/verifyUploads.py --output reports/signedReadMinio.json`：真实隔离 MinIO 的新读取选项、原上传/分片与存储契约通过，见 [报告](signedReadMinio.json)和[日志](signedReadMinio.txt)。独立容器无外部网络、不映射端口，已清理，原有容器保持运行。
+
+首次 MinIO 回归中，原有契约故意发送错误长度触发 SDK 重试退避，耗尽契约的 10 秒预算。测试专用 client 改为 MaxRetries=1，与现有协议测试一致；生产 client 配置未变，修正后通过。
+
+## 覆盖内容
+
+- 默认 attachment、inline、可选 MIME、ASCII/中文/特殊字符文件名，拒绝 CR/LF、控制字符、路径、过长参数、非法 MIME 和 disposition。
+- 本地签名绑定版本、key、有效期、全部响应选项，重复参数、未知参数、签名篡改、版本剥离和旧下载 URL 注入 inline 均拒绝，拒绝前不读存储。
+- 30 分钟实际签名到期时间、TTL 上下限、精确到期边界、取消 context；过期 Range/HEAD/条件请求不得读取文件或返回缓存命中。
+- 本地真实文件 GET/HEAD 内容长度、前缀/后缀/开放区间/截断/多段范围、206/416，Seek 不暴露元数据，按范围读取而非全文件缓冲；顺序读取 Store 回退完整 200。
+- 错误及条件响应保持 private/no-store，HEAD 成功与失败均无响应体。
+- OSS SDK V1/V4 独立重新计算签名，验证响应头在签名前加入，中文文件名、配置域名、到期时间及选项篡改；拒绝未签名配置。S3/R2 验证原生 SDK 查询参数与实际到期时间。
+- MinIO 实际 GET/Range 的响应头、字节和状态正确，篡改 disposition/type/cache/expiry 被服务端拒绝。
+
+## 验证边界
+
+OSS/R2 未使用云账号实测；SDK/MinIO 验证不能代替实际桶和域名验收。OSS 默认域名可能强制下载，其响应头覆盖受平台规则限制，需部署方检查实际 200/206。
+
+浏览器控制工具不可用，隔离 Chrome/Chromium 截图尝试未获得成功渲染证据，因此不计为浏览器预览通过。真实 PDF 的 HTTP 响应已检查，浏览器视觉预览与实际云域名接入仍需项目侧回归。
+
+远程固定版本空缓存验收结果在发布后记录；不移动已发布标签。
--- a/reports/signedReadMinio.json
+++ b/reports/signedReadMinio.json
@@ -0,0 +1,111 @@
+{
+  "status": "passed",
+  "startedAt": "2026-09-30T14:35:32.113432+00:00",
+  "architecture": "arm64",
+  "goVersion": "go version go1.27.1 darwin/arm64",
+  "image": "quay.io/minio/minio:RELEASE.2025-09-07T16-13-09Z",
+  "imageId": "sha256:8f08aee614800a237906bd48114d733e5ac5bfac4ccdf731f141b0e880d7a253",
+  "sourceSha256": {
+    "go.mod": "e3877788b18b605a007530f80b684f06a7ae308844c2959a8750ed55ae8037a3",
+    "go.sum": "53c136b153ec7c91731f7c927dfda540fbd683037f3fbd1f3d067b1ec7aabc15",
+    "internal/storagefixture/multipart.go": "da9ec938b3bdb872e10e4f874b6a0224121c14a631dcf4e86d7ebbc1cd34a770",
+    "internal/storagefixture/server.go": "defacc905246a643faf5371e437f9ce458f05461e0a922766034d1f9ffdaf003",
+    "storage/local/local.go": "5d1ca75d0d2ca87981eef84a60bf98d0feefa2a9594940d6bd231877f4f8ec02",
+    "storage/local/local_test.go": "3a2241840968df8e37fd67169c3ef708228449e81f65aff908c8b60d49434dc0",
+    "storage/local/read_test.go": "ef1f7feb0887ea4b1f30304dfaf542fe9788b6e17856c942f1cd98448656194f",
+    "storage/multipart.go": "3b718ebe6da681c89a3f797892c88e7acb15c295df2376d64ac35da0976ed69d",
+    "storage/multipart_test.go": "4053f680f7795db2a6b4aa23590b3669eec7a609dd92c4a1e20891a5299274ee",
+    "storage/oss/oss.go": "4216ce9f3fe3ac5418a5b809db3cef7e99dcca72a25a2a12301f5897cda85dd5",
+    "storage/oss/oss_test.go": "555a954010b1218804dc7951fc75e42eae24eba9a99c0871f5ba787f3fc87d45",
+    "storage/oss/read.go": "429a9a9f6c586a885d7cccb76c9d572d53a79df637ff128caacb2eac35b8d862",
+    "storage/oss/read_test.go": "a1c273cfedd2f3ee31ce407a7ddd6fd5ad02c65ad632a91bc7f3ead3712b5bbd",
+    "storage/oss/upload.go": "556129611f9e5549cac8a36b4026bfb19c112a295b55192579f9ac116e20626f",
+    "storage/oss/upload_test.go": "08eb0ed157f3743288d781f61d4d2b7bfe77852a8259c5e598c719d35889409e",
+    "storage/read.go": "92787c74ae024822f82b5b84bffc9f8a355f1f2565b99ca7fbefe49157ef4851",
+    "storage/read_test.go": "9b11ab9640e98c1c9fa7ce1e2587df217e874e3a6a6e27a0dd0ade6fbf3d5e1a",
+    "storage/s3/config.go": "626ec6a2c0b06c95ee7eb7aa0832b190cfcdeb8a127b6b89e99204040bc3b041",
+    "storage/s3/read.go": "319b57f2ecf435b71085c7cdcafd50a1e30caa5f357f83d4db3cdcef085792b6",
+    "storage/s3/read_test.go": "9b64fda5c83ba41508ec23cf41aeeb9826b677caaa851dcbeb04abe1f43eed65",
+    "storage/s3/s3.go": "016bef5948e97f3d043d2e858716f1c02d9f27c4e02802bdc1be3860116f4b6c",
+    "storage/s3/s3_test.go": "9ef284926ec9936ddfec8c52a9bf04fc7b4be55c43a535f6c5a428d1535f6fec",
+    "storage/s3/upload.go": "3ce0b3626249ffe7a041606d6a9481743af8a0d4868fadea20ed3ed44ee0c765",
+    "storage/s3/upload_test.go": "a41fdbd100d9c79a3606c5942f98017afe26d841b251d96e979df87d0af93867",
+    "storage/signed.go": "ae4b144137627be35718c40743ebc2f063ec667c24b6d8984ccfcca034a73787",
+    "storage/signedUpload.go": "a8d31bcbbad64796f04611e69271e94d917c9bcd5aeabd7a97ea155b0093c814",
+    "storage/signed_test.go": "eaffd40894018814e976477f96cf0fbaecfa1987caad78830d9fc8e96995882f",
+    "storage/storage.go": "cb670872f01cf1d7b4ebf21cec9fc6f52ad93bfdf523b2f28bbb8d9c7fe39a6c",
+    "storage/storagetest/contract.go": "e7ad7242102437882269d4066462059d7974586b36a82d18639eca10fd932be9",
+    "storage/storagetest/uploads.go": "9b66f86dd94ccdf30c7d603d432bc2a55956608898e46c1274fa27d16fa1a969",
+    "storage/upload.go": "9ff2930ba389163acc8063b51107c09a60290609ba384de8004c498ce09f20a1",
+    "storage/upload_test.go": "12b60419807ed64b89e30861674e19abee7b0b7bb0e8ec9ac5b3aa2e0710a1da"
+  },
+  "commands": [
+    [
+      "go",
+      "test",
+      "-p=2",
+      "-c",
+      "-o",
+      "/var/folders/wm/1sg73x8n7879sp3t6m4jpnrr0000gn/T/goOmniUpload3cba6ibp/s3.test",
+      "./storage/s3"
+    ],
+    [
+      "docker",
+      "run",
+      "--rm",
+      "--name",
+      "go-omni-upload-c388755df4ec",
+      "--platform",
+      "linux/arm64",
+      "--cpus",
+      "2",
+      "--memory",
+      "2048m",
+      "--memory-swap",
+      "2048m",
+      "--pids-limit",
+      "256",
+      "--network",
+      "none",
+      "--read-only",
+      "--cap-drop",
+      "ALL",
+      "--security-opt",
+      "no-new-privileges",
+      "--user",
+      "1000:1000",
+      "--tmpfs",
+      "/tmp:rw,nosuid,noexec,size=64m,mode=1777",
+      "--tmpfs",
+      "/data:rw,nosuid,noexec,size=128m,mode=1777",
+      "-v",
+      "/var/folders/wm/1sg73x8n7879sp3t6m4jpnrr0000gn/T/goOmniUpload3cba6ibp:/test:ro",
+      "-e",
+      "GOMAXPROCS=2",
+      "-e",
+      "MINIO_ROOT_USER=goOmniTest",
+      "-e",
+      "MINIO_ROOT_PASSWORD=goOmniTestSecret",
+      "-e",
+      "GO_OMNI_S3_TEST_ADDR=127.0.0.1:9000",
+      "--entrypoint",
+      "sh",
+      "quay.io/minio/minio:RELEASE.2025-09-07T16-13-09Z",
+      "-c",
+      "set -eu\nminio --version\nminio server /data --address 127.0.0.1:9000 --console-address 127.0.0.1:9001 >/tmp/minio.log 2>&1 &\nserver=$!\ntrap 'kill \"$server\" 2>/dev/null || true; wait \"$server\" 2>/dev/null || true' EXIT\n/test/s3.test -test.v -test.run '^TestS3Integration$' -test.count=1 -test.timeout=60s || { cat /tmp/minio.log; exit 1; }\n"
+    ]
+  ],
+  "containerLimits": {
+    "cpus": 2,
+    "memoryBytes": 2147483648,
+    "pids": 256,
+    "network": "none"
+  },
+  "notes": [
+    "MinIO verifies S3 signatures; OSS/R2 real cloud accounts are not exercised."
+  ],
+  "preExistingContainersStillRunning": true,
+  "cleanedContainer": "go-omni-upload-c388755df4ec",
+  "finishedAt": "2026-09-30T14:35:34.723540+00:00",
+  "logSha256": "c25db6c44baee149c1e3d6d3b7f81faac9483eb79709bed25f61b03d7b9b3133"
+}
--- a/reports/signedReadMinio.txt
+++ b/reports/signedReadMinio.txt
@@ -0,0 +1,7 @@
+minio version RELEASE.2025-09-07T16-13-09Z (commit-id=07c3a429bfed433e49018cb0f78a52145d4bedeb)
+Runtime: go1.24.6 linux/arm64
+License: GNU AGPLv3 - https://www.gnu.org/licenses/agpl-3.0.html
+Copyright: 2015-2025 MinIO, Inc.
+=== RUN   TestS3Integration
+--- PASS: TestS3Integration (0.63s)
+PASS
--- a/scripts/verifyManagedRelease.py
+++ b/scripts/verifyManagedRelease.py
@@ -162,6 +162,11 @@ def main():
                   "remoteCheckConfigBeforeDependencies", "removedImplicitEnvironmentRules"]

        for package, expected in {
+            "storage": {"TestReadOptions", "TestReadSignatureAndExpiry", "TestReadRangeStreamingAndCache"},
+            "storage/local": {"TestSignedPayloadRanges"},
+            "storage/oss": {"TestReadOptionsNativeSignatures"},
+            "storage/s3": {"TestReadOptionsS3AndR2"},
+            "examples/signedRead": {"TestSignedReadHTTP"},
            "copyx": {"TestCheckTypesAndEmptyCollections", "TestCheckRulesAndConverterBoundaries", "TestCopierCheckConcurrentAndOptionsIsolation"},
            "logx": {"TestLoggerTimeZoneIsolation", "TestLoggerTimeZoneValidationAndDST", "TestLoggerTimeZoneConcurrentChildren"},
            "cors": {"TestPolicyPreflightAndActual", "TestPolicyValidation", "TestPolicyCredentialsWildcardAndDuplicates", "TestPolicyPreservesHTTPAndSnapshot"},
@@ -181,6 +186,11 @@ def main():
            events = [json.loads(line) for line in output.splitlines() if line.startswith("{")]
            passed = {event.get("Test") for event in events if event.get("Action") == "pass"}
            assert expected <= passed
+        signed_read_output = run(["go", "run", MODULE + "/examples/signedRead", "-check"], starter, env)
+        assert "PDF preview, Chinese filename, download, HEAD and Range passed" in signed_read_output
+        checks += ["remoteSignedReadOptionsAndLegacyLinks", "remoteReadSignatureTamperingAndExpiry",
+                   "remoteLocalPayloadRangesAndHEAD", "remoteOSSNativeV1V4Signatures",
+                   "remoteS3R2ReadOptions", "remoteSignedReadHTTPExample"]
        checks += ["remotePreciseModuleDiagnostics", "remoteJSONSuccessStatuses", "remoteRejectedStatusBodyCleanup",
                   "remoteCopyTypePreflight", "remoteEmptyCollectionTypeRejection", "remoteLoggerTimeZoneIsolation",
                   "remoteCORSPolicyRace", "remoteCORSErrorResponses", "remoteCORSTransports", "generatedCORSConfigOnly"]
@@ -247,6 +257,8 @@ def main():
    sources += ["app/body.go", "app/router.go", "app/requests.go", "app/bodyPolicy_test.go", "app/requests_test.go", "app/transport_test.go",
                "httpx/context.go", "internal/httplimits/limits.go", "lifecycle/runtime_test.go", "transport/http2/server.go", "transport/http2/lifecycle_test.go",
                "transport/native/server.go", "transport/native/earlyReject_test.go", "examples/httpSafety/main.go"]
+    sources += [str(p.relative_to(ROOT)) for p in (ROOT / "storage").rglob("*.go")]
+    sources += [str(p.relative_to(ROOT)) for p in (ROOT / "examples/signedRead").glob("*.go")]
    report = {"passed": True, "frameworkVersion": args.version, "frameworkSum": dependency["Sum"],
              "freshModuleCache": True, "noLocalReplace": True,
              "durationSeconds": round(time.monotonic() - started, 2), "checks": checks,
--- a/storage/README.md
+++ b/storage/README.md
@@ -6,12 +6,42 @@
 | --- | --- | --- | --- | --- |
 | 读写删除 | Store | 支持 | 支持 | 支持 |
 | 临时下载 | Presigner | NewSigner | 支持 | 支持 |
+| 带选项的预览/下载 | ReadPresigner | NewSigner | 支持 | 支持 |
 | 限定大小/类型的直传 | UploadPresigner | NewUploadSigner | 支持 | 支持，需要配置签名 Header |
 | 创建、上传、查询、完成、取消分片 | MultipartStore | 当前不提供 | 支持 | 支持 |
 | 分片直传签名 | PartPresigner | 当前不提供 | 支持 | 支持，需要配置签名 Header |

 没有固定业务字段、目录规则或身份模型。鉴权、对象归属、业务配额由应用定义。SDK 客户端和连接池由应用持有；适配器不会在一次调用后关闭客户端。

+## 签名预览与下载
+
+`v0.29.0-preview` 新增独立的可选接口 `ReadPresigner`，不扩充原 Store/Presigner，不要求第三方适配器修改代码。原 `PresignGet(ctx, key, ttl)` 和既有本地下载链接继续有效、默认 attachment。
+
+```go
+// signer 可以是 storage.NewSigner 返回的本地 Handler，或 S3/R2、OSS Store。
+link, err := signer.PresignGetWithOptions(ctx, key, 30*time.Minute, storage.ReadOptions{
+    Disposition: storage.DispositionInline,
+    FileName: "示例报告.pdf",
+    ContentType: "application/pdf",
+})
+if err != nil { return err }
+// 把 link.URL 和 link.ExpiresAt 返回给已授权的调用方。
+```
+
+TTL 仍为 1 秒到 1 小时，30 分钟无需改配置。`ReadLink` 包含 `url` 和 `expiresAt`，到期时间取自实际签名，精确到秒（不足一秒的部分舍弃）；临时云凭据可能更早失效。无需额外请求 Header，客户端直接打开 URL。可通过 `storage.ReadPresigner` 做能力判断；不支持时由调用方明确处理，不应静默降级成公开地址。
+
+`Disposition` 只接受 inline/attachment，空值为 attachment。`FileName` 是显示名，与存储 key 无关；中文使用标准 `filename*` 编码，拒绝控制字符（包括 CR/LF）、路径分隔符及超长值。`ContentType` 为空时沿用对象元数据，可显式指定合法 MIME 类型；它只控制响应，不转换或验证文件内容。PDF 应在上传时就保存 `application/pdf` 元数据。inline 请求内联显示，能否展示还取决于浏览器的格式支持与用户设置。
+
+本地签名绑定 key、到期时间、版本及全部选项，拒绝重复/未知参数和篡改；先验签、验有效期，再读取对象或处理条件请求。Local 使用受文件内容边界约束的流，GET/HEAD 的长度不包含内部元数据；支持单段/多段 Range、206/416，以及 Last-Modified 条件请求。HEAD 返回完整对象头、无响应体，忽略 Range。自定义 Store 的 Body 实现 `io.ReadSeeker` 时复用同一行为；仅支持顺序读取时返回完整 200，不宣称支持范围读取，也不把整个对象加载到内存。
+
+云端适配器在 OSS/S3 原生 SDK 签名前传入响应参数，禁止先签名后拼参数或替换域名。Range 由云存储处理；云端 GET 签名不能直接改成 HEAD 使用。新接口请求 `Cache-Control: private, no-store`，本地成功、错误及条件响应均保持该策略；云端响应头覆盖受平台规则约束，需检查实际 200/206 响应与代理缓存配置。
+
+OSS 默认域名或加速域名可能强制下载。需要自定义域名时，在应用装配 SDK client 时设置已绑定桶的域名和 `WithUseCName(true)`，再传给适配器；SDK 的区域、签名版本、凭据由应用配置。例如在现有 SDK config 上调用 `WithEndpoint("https://files.example").WithUseCName(true)`。参见 [OSS 预览规则](https://help.aliyun.com/zh/oss/how-to-ensure-an-object-is-previewed-when-you-access-the-object)与 [GetObject 响应参数规则](https://www.alibabacloud.com/help/en/oss/developer-reference/getobject)。
+
+签发权限、对象是否不可变、审计和前端链接复用由项目维护。框架不添加分享表、撤销、租户或数据库依赖；重新签发不会撤销旧链接，到期不会收回已下载内容，也不会中断已开始的传输。本地入口使用显式配置的公开 baseURL，不猜测 Host/转发头，不公开磁盘目录。应用与代理日志应隐藏查询参数。
+
+完整离线 [预览/下载示例](../examples/signedRead/README.md)，包含真实 HTTP 检查与一页 PDF。OSS V1/V4、S3/R2 SDK 签名和隔离 MinIO 有回归；OSS/R2 云账号尚未实测，部署方仍需对实际桶、域名及浏览器进行验收。
+
 ## 服务端上传限制

 ```go
--- a/storage/local/local.go
+++ b/storage/local/local.go
@@ -151,14 +151,31 @@ func (s *Store) Get(ctx context.Context, key string) (storage.Object, error) {
 	}
 	info.ModifiedAt = stat.ModTime()
 	ok = true
-	return storage.Object{Info: info, Body: &body{Reader: storage.ContextReader{Context: ctx, Reader: io.LimitReader(f, info.Size)}, Closer: f}}, nil
+	// Expose only the payload as a seekable section. Seeks are relative to the
+	// object, never to our private metadata header or other disk bytes.
+	return storage.Object{Info: info, Body: &body{section: io.NewSectionReader(f, int64(length)+4, info.Size), file: f, ctx: ctx}}, nil
 }

 type body struct {
-	io.Reader
-	io.Closer
+	section *io.SectionReader
+	file    *os.File
+	ctx     context.Context
 }

+func (b *body) Read(p []byte) (int, error) {
+	if err := b.ctx.Err(); err != nil {
+		return 0, err
+	}
+	return b.section.Read(p)
+}
+func (b *body) Seek(offset int64, whence int) (int64, error) {
+	if err := b.ctx.Err(); err != nil {
+		return 0, err
+	}
+	return b.section.Seek(offset, whence)
+}
+func (b *body) Close() error { return b.file.Close() }
+
 func (s *Store) Delete(ctx context.Context, key string) error {
 	if err := storage.Check(ctx, key); err != nil {
 		return err
--- a/storage/local/read_test.go
+++ b/storage/local/read_test.go
@@ -0,0 +1,125 @@
+package local
+
+import (
+	"context"
+	"io"
+	"mime"
+	"mime/multipart"
+	"net/http/httptest"
+	"strconv"
+	"strings"
+	"testing"
+	"time"
+
+	"git.yuntuo.hk/k2safe/go-omni/storage"
+)
+
+func TestSignedPayloadRanges(t *testing.T) {
+	store, err := New(t.TempDir(), 1<<20)
+	if err != nil {
+		t.Fatal(err)
+	}
+	data := "%PDF-1.4\n" + strings.Repeat("0123456789", 100) + "\n%%EOF\n"
+	ctx := context.Background()
+	if _, err = store.Put(ctx, "private/document", strings.NewReader(data), int64(len(data)), "application/pdf"); err != nil {
+		t.Fatal(err)
+	}
+	signer, _ := storage.NewSigner(store, "https://files.example/read", []byte(strings.Repeat("s", 32)))
+	link, err := signer.PresignGetWithOptions(ctx, "private/document", 30*time.Minute, storage.ReadOptions{Disposition: storage.DispositionInline, FileName: "示例.pdf"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, tc := range []struct {
+		method, span string
+		status       int
+		want         string
+	}{
+		{"GET", "", 200, data}, {"HEAD", "", 200, ""}, {"HEAD", "bytes=0-3", 200, ""},
+		{"GET", "bytes=0-7", 206, data[:8]}, {"GET", "bytes=20-", 206, data[20:]}, {"GET", "bytes=-6", 206, data[len(data)-6:]},
+		{"GET", "bytes=1000-999999", 206, data[1000:]}, {"GET", "bytes=999999-", 416, ""}, {"GET", "bytes=bad", 416, ""},
+	} {
+		t.Run(tc.method+tc.span, func(t *testing.T) {
+			r := httptest.NewRequest(tc.method, link.URL, nil)
+			if tc.span != "" {
+				r.Header.Set("Range", tc.span)
+			}
+			w := httptest.NewRecorder()
+			signer.ServeHTTP(w, r)
+			if w.Code != tc.status {
+				t.Fatal(w.Code)
+			}
+			if tc.status != 416 && w.Body.String() != tc.want {
+				t.Fatal("wrong payload slice")
+			}
+			if tc.status == 206 && (w.Header().Get("Content-Length") != strconv.Itoa(len(tc.want)) || !strings.HasSuffix(w.Header().Get("Content-Range"), "/"+strconv.Itoa(len(data)))) {
+				t.Fatal(w.Header())
+			}
+			if tc.status == 200 && w.Header().Get("Content-Length") != strconv.Itoa(len(data)) {
+				t.Fatal("metadata included in length")
+			}
+			if tc.span == "bytes=999999-" && w.Header().Get("Content-Range") != "bytes */"+strconv.Itoa(len(data)) {
+				t.Fatal(w.Header())
+			}
+			if w.Header().Get("Cache-Control") != "private, no-store" {
+				t.Fatal("cache policy")
+			}
+			if tc.status != 416 {
+				kind, params, err := mime.ParseMediaType(w.Header().Get("Content-Disposition"))
+				if err != nil || kind != "inline" || params["filename"] != "示例.pdf" || w.Header().Get("Content-Type") != "application/pdf" {
+					t.Fatal(w.Header(), err)
+				}
+			}
+		})
+	}
+	r := httptest.NewRequest("GET", link.URL, nil)
+	r.Header.Set("Range", "bytes=0-3,10-13")
+	w := httptest.NewRecorder()
+	signer.ServeHTTP(w, r)
+	kind, params, err := mime.ParseMediaType(w.Header().Get("Content-Type"))
+	if err != nil || w.Code != 206 || kind != "multipart/byteranges" {
+		t.Fatal(w.Header(), err)
+	}
+	reader := multipart.NewReader(w.Body, params["boundary"])
+	for _, want := range []string{data[:4], data[10:14]} {
+		p, err := reader.NextPart()
+		if err != nil {
+			t.Fatal(err)
+		}
+		got, err := io.ReadAll(p)
+		if err != nil || string(got) != want {
+			t.Fatal("multipart bytes", err)
+		}
+	}
+	if _, err := reader.NextPart(); err != io.EOF {
+		t.Fatal(err)
+	}
+	// Random access cannot expose the managed header and still observes context.
+	ctx, cancel := context.WithCancel(ctx)
+	defer cancel()
+	object, err := store.Get(ctx, "private/document")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer object.Body.Close()
+	seeker := object.Body.(io.ReadSeeker)
+	if size, err := seeker.Seek(0, io.SeekEnd); err != nil || size != int64(len(data)) {
+		t.Fatal(size, err)
+	}
+	if _, err := seeker.Seek(-1, io.SeekStart); err == nil {
+		t.Fatal("seek into header")
+	}
+	if _, err := seeker.Seek(0, io.SeekStart); err != nil {
+		t.Fatal(err)
+	}
+	prefix := make([]byte, 8)
+	if _, err := io.ReadFull(seeker, prefix); err != nil || string(prefix) != data[:8] {
+		t.Fatal("metadata exposed", err)
+	}
+	cancel()
+	if _, err := seeker.Seek(0, io.SeekStart); err != context.Canceled {
+		t.Fatal(err)
+	}
+	if _, err := seeker.Read(prefix); err != context.Canceled {
+		t.Fatal(err)
+	}
+}
--- a/storage/oss/read.go
+++ b/storage/oss/read.go
@@ -0,0 +1,59 @@
+package oss
+
+import (
+	"context"
+	"errors"
+	"net/url"
+	"strconv"
+	"time"
+
+	"git.yuntuo.hk/k2safe/go-omni/storage"
+	sdk "github.com/aliyun/alibabacloud-oss-go-sdk-v2/oss"
+)
+
+func (s *Store) PresignGetWithOptions(ctx context.Context, key string, ttl time.Duration, options storage.ReadOptions) (storage.ReadLink, error) {
+	if err := storage.Check(ctx, key); err != nil {
+		return storage.ReadLink{}, err
+	}
+	if ttl < time.Second || ttl > time.Hour {
+		return storage.ReadLink{}, errors.New("storage/oss: TTL must be 1s..1h")
+	}
+	headers, err := options.ResponseHeaders()
+	if err != nil {
+		return storage.ReadLink{}, err
+	}
+	request := &sdk.GetObjectRequest{Bucket: sdk.Ptr(s.bucket), Key: sdk.Ptr(key), ResponseContentDisposition: sdk.Ptr(headers.Get("Content-Disposition")), ResponseCacheControl: sdk.Ptr(headers.Get("Cache-Control"))}
+	if contentType := headers.Get("Content-Type"); contentType != "" {
+		request.ResponseContentType = sdk.Ptr(contentType)
+	}
+	r, err := s.client.Presign(ctx, request, sdk.PresignExpires(ttl))
+	if err != nil {
+		return storage.ReadLink{}, err
+	}
+	if len(r.SignedHeaders) != 0 {
+		return storage.ReadLink{}, errors.New("storage/oss: direct GET requires a signature without additional request headers")
+	}
+	u, err := url.Parse(r.URL)
+	if err != nil {
+		return storage.ReadLink{}, errors.New("storage/oss: invalid signed URL")
+	}
+	q := u.Query()
+	var expires time.Time
+	if q.Get("x-oss-signature") != "" {
+		start, e := time.Parse("20060102T150405Z", q.Get("x-oss-date"))
+		seconds, e2 := strconv.ParseInt(q.Get("x-oss-expires"), 10, 64)
+		if e != nil || e2 != nil || seconds < 1 || seconds > 3600 {
+			return storage.ReadLink{}, errors.New("storage/oss: invalid signed expiry")
+		}
+		expires = start.Add(time.Duration(seconds) * time.Second)
+	} else {
+		seconds, e := strconv.ParseInt(q.Get("Expires"), 10, 64)
+		if e != nil || q.Get("Signature") == "" {
+			return storage.ReadLink{}, errors.New("storage/oss: missing signed expiry")
+		}
+		expires = time.Unix(seconds, 0).UTC()
+	}
+	return storage.ReadLink{URL: r.URL, ExpiresAt: expires}, nil
+}
+
+var _ storage.ReadPresigner = (*Store)(nil)
--- a/storage/oss/read_test.go
+++ b/storage/oss/read_test.go
@@ -0,0 +1,140 @@
+package oss
+
+import (
+	"context"
+	"crypto/hmac"
+	"crypto/sha1"
+	"crypto/sha256"
+	"encoding/base64"
+	"encoding/hex"
+	"mime"
+	"net/url"
+	"sort"
+	"strconv"
+	"strings"
+	"testing"
+	"time"
+
+	"git.yuntuo.hk/k2safe/go-omni/storage"
+	sdk "github.com/aliyun/alibabacloud-oss-go-sdk-v2/oss"
+	"github.com/aliyun/alibabacloud-oss-go-sdk-v2/oss/credentials"
+	"github.com/aliyun/alibabacloud-oss-go-sdk-v2/oss/signer"
+)
+
+// Recompute signatures independently from the SDK using fixed test credentials.
+// This catches response parameters appended after signing, not just their presence.
+func validReadSignature(u *url.URL, version sdk.SignatureVersionType) bool {
+	q := u.Query()
+	if version == sdk.SignatureVersionV1 {
+		var keys []string
+		for key := range q {
+			if strings.HasPrefix(key, "response-") {
+				keys = append(keys, key)
+			}
+		}
+		sort.Strings(keys)
+		var params []string
+		for _, key := range keys {
+			params = append(params, key+"="+q.Get(key))
+		}
+		message := "GET\n\n\n" + q.Get("Expires") + "\n/testbucket/folder/file.pdf?" + strings.Join(params, "&")
+		mac := hmac.New(sha1.New, []byte("fixtureSecret"))
+		mac.Write([]byte(message))
+		return hmac.Equal([]byte(q.Get("Signature")), []byte(base64.StdEncoding.EncodeToString(mac.Sum(nil))))
+	}
+	signature := q.Get("x-oss-signature")
+	q.Del("x-oss-signature")
+	canonical := "GET\n/testbucket/folder/file.pdf\n" + strings.ReplaceAll(q.Encode(), "+", "%20") + "\n\n\nUNSIGNED-PAYLOAD"
+	hash := sha256.Sum256([]byte(canonical))
+	_, scope, _ := strings.Cut(q.Get("x-oss-credential"), "/")
+	message := "OSS4-HMAC-SHA256\n" + q.Get("x-oss-date") + "\n" + scope + "\n" + hex.EncodeToString(hash[:])
+	key := []byte("aliyun_v4fixtureSecret")
+	for _, part := range strings.Split(scope, "/") {
+		mac := hmac.New(sha256.New, key)
+		mac.Write([]byte(part))
+		key = mac.Sum(nil)
+	}
+	mac := hmac.New(sha256.New, key)
+	mac.Write([]byte(message))
+	return hmac.Equal([]byte(signature), []byte(hex.EncodeToString(mac.Sum(nil))))
+}
+
+func TestReadOptionsNativeSignatures(t *testing.T) {
+	for name, version := range map[string]sdk.SignatureVersionType{"v1": sdk.SignatureVersionV1, "v4": sdk.SignatureVersionV4} {
+		t.Run(name, func(t *testing.T) {
+			cfg := sdk.LoadDefaultConfig().WithRegion("cn-hangzhou").WithEndpoint("https://files.example").WithUseCName(true).WithSignatureVersion(version).WithCredentialsProvider(credentials.NewStaticCredentialsProvider("fixtureAccess", "fixtureSecret"))
+			store, err := New(sdk.NewClient(cfg), "testbucket", 64)
+			if err != nil {
+				t.Fatal(err)
+			}
+			for _, options := range []storage.ReadOptions{{}, {Disposition: storage.DispositionInline, FileName: "报告 2026.pdf", ContentType: "application/pdf"}, {Disposition: storage.DispositionAttachment, FileName: "download.pdf"}} {
+				before := time.Now().UTC().Truncate(time.Second)
+				link, err := store.PresignGetWithOptions(context.Background(), "folder/file.pdf", 30*time.Minute, options)
+				if err != nil {
+					t.Fatal(err)
+				}
+				u, err := url.Parse(link.URL)
+				if err != nil {
+					t.Fatal(err)
+				}
+				q := u.Query()
+				if u.Host != "files.example" || u.Path != "/folder/file.pdf" || !validReadSignature(u, version) {
+					t.Fatal("SDK response overrides were not signed")
+				}
+				disposition, params, err := mime.ParseMediaType(q.Get("response-content-disposition"))
+				want := options.Disposition
+				if want == "" {
+					want = "attachment"
+				}
+				if err != nil || disposition != want || params["filename"] != options.FileName || q.Get("response-content-type") != options.ContentType || q.Get("response-cache-control") != "private, no-store" {
+					t.Fatal("wrong signed headers", err)
+				}
+				if link.ExpiresAt.Before(before.Add(30*time.Minute)) || link.ExpiresAt.After(time.Now().Add(30*time.Minute)) {
+					t.Fatal("expiry drift")
+				}
+				var expires time.Time
+				if version == sdk.SignatureVersionV4 {
+					start, _ := time.Parse("20060102T150405Z", q.Get("x-oss-date"))
+					seconds, _ := strconv.Atoi(q.Get("x-oss-expires"))
+					expires = start.Add(time.Duration(seconds) * time.Second)
+				} else {
+					seconds, _ := strconv.ParseInt(q.Get("Expires"), 10, 64)
+					expires = time.Unix(seconds, 0)
+				}
+				if !expires.Equal(link.ExpiresAt) {
+					t.Fatal("result does not match signature expiry")
+				}
+				for _, name := range []string{"response-content-disposition", "response-content-type", "response-cache-control"} {
+					changed := *u
+					query := changed.Query()
+					query.Set(name, "changed")
+					changed.RawQuery = query.Encode()
+					if validReadSignature(&changed, version) {
+						t.Fatal("unsigned override", name)
+					}
+				}
+			}
+			for _, ttl := range []time.Duration{0, time.Second - time.Nanosecond, time.Hour + time.Nanosecond} {
+				if _, err := store.PresignGetWithOptions(context.Background(), "file", ttl, storage.ReadOptions{}); err == nil {
+					t.Fatal("TTL accepted")
+				}
+			}
+			for _, options := range []storage.ReadOptions{{FileName: "x\r\nY: z"}, {ContentType: "text/plain\r\nY: z"}, {Disposition: "bad"}} {
+				if _, err := store.PresignGetWithOptions(context.Background(), "file", time.Minute, options); err == nil {
+					t.Fatal("invalid header accepted")
+				}
+			}
+			ctx, cancel := context.WithCancel(context.Background())
+			cancel()
+			if _, err := store.PresignGetWithOptions(ctx, "file", time.Minute, storage.ReadOptions{}); err != context.Canceled {
+				t.Fatal(err)
+			}
+		})
+	}
+	// A caller-supplied unsigned SDK configuration cannot masquerade as a link.
+	client := sdk.NewClient(sdk.LoadDefaultConfig().WithRegion("cn-hangzhou").WithEndpoint("https://files.example").WithCredentialsProvider(credentials.NewStaticCredentialsProvider("fixtureAccess", "fixtureSecret")), func(o *sdk.Options) { o.Signer = &signer.NopSigner{} })
+	store, _ := New(client, "testbucket", 64)
+	if _, err := store.PresignGetWithOptions(context.Background(), "file", time.Minute, storage.ReadOptions{}); err == nil {
+		t.Fatal("unsigned URL accepted")
+	}
+}
--- a/storage/read.go
+++ b/storage/read.go
@@ -0,0 +1,72 @@
+package storage
+
+import (
+	"context"
+	"errors"
+	"mime"
+	"net/http"
+	"strings"
+	"time"
+	"unicode"
+	"unicode/utf8"
+)
+
+const (
+	DispositionAttachment = "attachment"
+	DispositionInline     = "inline"
+)
+
+// ReadOptions controls the response to one signed GET. Empty Disposition means
+// attachment; empty ContentType preserves object metadata. FileName is a display
+// name, not an object key or filesystem path. All options are signed.
+type ReadOptions struct {
+	Disposition string
+	FileName    string
+	ContentType string
+}
+
+// ReadLink grants GET access without additional request headers. ExpiresAt is
+// the expiry encoded in the signature, at second precision. Provider credentials
+// may expire earlier. Do not log the URL. Issuing another link does not revoke it.
+type ReadLink struct {
+	URL       string    `json:"url"`
+	ExpiresAt time.Time `json:"expiresAt"`
+}
+
+// ReadPresigner is optional; existing Store and Presigner implementations do not
+// need to change. Cloud GET signatures do not also authorize HEAD requests.
+type ReadPresigner interface {
+	PresignGetWithOptions(context.Context, string, time.Duration, ReadOptions) (ReadLink, error)
+}
+
+// ResponseHeaders validates options and returns a fresh set of response headers
+// for provider adapters to include BEFORE signing, requesting private, no-store.
+func (o ReadOptions) ResponseHeaders() (http.Header, error) {
+	disposition := o.Disposition
+	if disposition == "" {
+		disposition = DispositionAttachment
+	}
+	if disposition != DispositionAttachment && disposition != DispositionInline {
+		return nil, errors.New("storage: disposition must be inline or attachment")
+	}
+	if len(o.FileName) > 1024 || !utf8.ValidString(o.FileName) || strings.IndexFunc(o.FileName, unicode.IsControl) >= 0 || strings.ContainsAny(o.FileName, `/\`) || o.FileName == "." || o.FileName == ".." {
+		return nil, errors.New("storage: invalid display filename")
+	}
+	params := map[string]string{}
+	if o.FileName != "" {
+		params["filename"] = o.FileName
+	}
+	h := http.Header{"Content-Disposition": {mime.FormatMediaType(disposition, params)}, "Cache-Control": {"private, no-store"}}
+	if o.ContentType != "" {
+		if !utf8.ValidString(o.ContentType) || strings.IndexFunc(o.ContentType, unicode.IsControl) >= 0 {
+			return nil, ErrContentType
+		}
+		kind, err := MediaType(o.ContentType)
+		if err != nil {
+			return nil, err
+		}
+		_, params, _ := mime.ParseMediaType(o.ContentType)
+		h.Set("Content-Type", mime.FormatMediaType(kind, params))
+	}
+	return h, nil
+}
--- a/storage/read_test.go
+++ b/storage/read_test.go
@@ -0,0 +1,219 @@
+package storage
+
+import (
+	"context"
+	"io"
+	"mime"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestReadOptions(t *testing.T) {
+	for _, name := range []string{"", "report.pdf", "报告 2026.pdf", `a";b.pdf`, "100%.pdf"} {
+		h, err := (ReadOptions{Disposition: DispositionInline, FileName: name, ContentType: "Application/PDF"}).ResponseHeaders()
+		if err != nil {
+			t.Fatal(err)
+		}
+		disposition, params, err := mime.ParseMediaType(h.Get("Content-Disposition"))
+		if err != nil || disposition != "inline" || params["filename"] != name || h.Get("Content-Type") != "application/pdf" || h.Get("Cache-Control") != "private, no-store" {
+			t.Fatal("invalid read headers", h, err)
+		}
+	}
+	h, err := (ReadOptions{}).ResponseHeaders()
+	if err != nil || h.Get("Content-Disposition") != "attachment" || h.Get("Content-Type") != "" {
+		t.Fatal(h, err)
+	}
+	for _, options := range []ReadOptions{
+		{Disposition: "form-data"}, {Disposition: "Inline"}, {Disposition: "inline\r\nX: y"},
+		{FileName: "x\r\nX: y"}, {FileName: "a\x00b"}, {FileName: "a\tb"}, {FileName: "bad\xff"}, {FileName: "a/b"}, {FileName: `a\b`}, {FileName: ".."}, {FileName: strings.Repeat("a", 1025)},
+		{ContentType: "bad"}, {ContentType: "image/*"}, {ContentType: "application/pdf\r\nX: y"}, {ContentType: "application/pdf\x00"}, {ContentType: strings.Repeat("x", 257)},
+	} {
+		if _, err := options.ResponseHeaders(); err == nil {
+			t.Fatal("invalid options accepted", options)
+		}
+	}
+}
+
+type readTestStore struct {
+	calls, bytes int
+	streaming    bool
+}
+
+func (*readTestStore) Put(context.Context, string, io.Reader, int64, string) (Info, error) {
+	panic("unused")
+}
+func (*readTestStore) Delete(context.Context, string) error { panic("unused") }
+func (s *readTestStore) Get(context.Context, string) (Object, error) {
+	s.calls++
+	body := &readTestBody{Reader: strings.NewReader("0123456789"), store: s}
+	var stream io.ReadCloser = body
+	if s.streaming {
+		stream = struct {
+			io.Reader
+			io.Closer
+		}{body, body}
+	}
+	return Object{Info: Info{Size: 10, ContentType: "application/pdf", ModifiedAt: time.Unix(1000, 0)}, Body: stream}, nil
+}
+
+type readTestBody struct {
+	*strings.Reader
+	store *readTestStore
+}
+
+func (b *readTestBody) Read(p []byte) (int, error) {
+	n, err := b.Reader.Read(p)
+	b.store.bytes += n
+	return n, err
+}
+func (*readTestBody) Close() error { return nil }
+
+func TestReadSignatureAndExpiry(t *testing.T) {
+	store := &readTestStore{}
+	s, _ := NewSigner(store, "https://files.example/read", []byte(strings.Repeat("s", 32)))
+	now := time.Unix(1800000000, 0).UTC()
+	s.now = func() time.Time { return now }
+	link, err := s.PresignGetWithOptions(context.Background(), "folder/file", 30*time.Minute, ReadOptions{Disposition: DispositionInline, FileName: "报告.pdf", ContentType: "application/pdf"})
+	if err != nil || !link.ExpiresAt.Equal(now.Add(30*time.Minute)) {
+		t.Fatal("incorrect expiry", err)
+	}
+	serve := func(method, address string, headers http.Header) *httptest.ResponseRecorder {
+		r := httptest.NewRequest(method, address, nil)
+		if headers != nil {
+			r.Header = headers
+		}
+		w := httptest.NewRecorder()
+		s.ServeHTTP(w, r)
+		return w
+	}
+	for _, method := range []string{"GET", "HEAD"} {
+		w := serve(method, link.URL, nil)
+		if w.Code != 200 || w.Header().Get("Content-Type") != "application/pdf" || w.Header().Get("Cache-Control") != "private, no-store" {
+			t.Fatal(w)
+		}
+		if method == "HEAD" && w.Body.Len() != 0 {
+			t.Fatal("HEAD body")
+		}
+	}
+	old, err := s.PresignGet(context.Background(), "folder/file", 30*time.Minute)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if w := serve("GET", old.String(), nil); w.Code != 200 || w.Header().Get("Content-Disposition") != "attachment" {
+		t.Fatal("legacy download changed")
+	}
+	mutations := []func(url.Values){
+		func(q url.Values) { q.Set("key", "other") }, func(q url.Values) { q.Set("expires", "1800001900") }, func(q url.Values) { q.Set("signature", "bad") },
+		func(q url.Values) { q.Set("filename", "other.pdf") }, func(q url.Values) { q.Set("disposition", "attachment") }, func(q url.Values) { q.Set("contentType", "text/html") },
+		func(q url.Values) { q.Set("v", "3") }, func(q url.Values) { q.Del("v") }, func(q url.Values) {
+			for _, k := range []string{"v", "filename", "disposition", "contentType"} {
+				q.Del(k)
+			}
+		},
+		func(q url.Values) { q.Set("extra", "x") }, func(q url.Values) { q.Set("filename", "evil\r\nX: yes") },
+	}
+	for _, key := range []string{"key", "expires", "signature", "v", "disposition", "filename", "contentType"} {
+		key := key
+		mutations = append(mutations, func(q url.Values) { q.Add(key, q.Get(key)) })
+	}
+	for _, mutate := range mutations {
+		u, _ := url.Parse(link.URL)
+		q := u.Query()
+		mutate(q)
+		u.RawQuery = q.Encode()
+		before := store.calls
+		if w := serve("GET", u.String(), http.Header{"Range": {"bytes=0-1"}}); w.Code != 403 || store.calls != before {
+			t.Fatal("tampered link reached storage")
+		}
+	}
+	u := *old
+	q := u.Query()
+	q.Set("disposition", "inline")
+	u.RawQuery = q.Encode()
+	if serve("GET", u.String(), nil).Code != 403 {
+		t.Fatal("legacy download upgraded by query")
+	}
+	if serve("GET", link.URL+"&bad=%ZZ", nil).Code != 403 {
+		t.Fatal("malformed query accepted")
+	}
+	before := store.calls
+	now = link.ExpiresAt.Add(-time.Nanosecond)
+	if serve("GET", link.URL, nil).Code != 200 {
+		t.Fatal("early expiration")
+	}
+	before = store.calls
+	now = link.ExpiresAt
+	for _, method := range []string{"GET", "HEAD"} {
+		w := serve(method, link.URL, http.Header{"Range": {"bytes=0-1"}, "If-Modified-Since": {"Fri, 01 Jan 2100 00:00:00 GMT"}})
+		if w.Code != 403 || store.calls != before || w.Header().Get("Cache-Control") != "private, no-store" {
+			t.Fatal("expired link reached storage or cache")
+		}
+		if method == "HEAD" && w.Body.Len() != 0 {
+			t.Fatal("HEAD error has body")
+		}
+	}
+	for _, ttl := range []time.Duration{0, time.Second - time.Nanosecond, time.Hour + time.Nanosecond} {
+		if _, err := s.PresignGetWithOptions(context.Background(), "key", ttl, ReadOptions{}); err == nil {
+			t.Fatal("invalid TTL")
+		}
+	}
+	for _, ttl := range []time.Duration{time.Second, time.Hour} {
+		if _, err := s.PresignGetWithOptions(context.Background(), "key", ttl, ReadOptions{}); err != nil {
+			t.Fatal(err)
+		}
+	}
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+	if _, err := s.PresignGetWithOptions(ctx, "key", time.Minute, ReadOptions{}); err != context.Canceled {
+		t.Fatal(err)
+	}
+}
+
+func TestReadRangeStreamingAndCache(t *testing.T) {
+	for _, streaming := range []bool{false, true} {
+		store := &readTestStore{streaming: streaming}
+		s, _ := NewSigner(store, "https://files.example/read", []byte(strings.Repeat("s", 32)))
+		link, _ := s.PresignGetWithOptions(context.Background(), "key", 30*time.Minute, ReadOptions{})
+		for _, method := range []string{"GET", "HEAD"} {
+			before := store.bytes
+			r := httptest.NewRequest(method, link.URL, nil)
+			r.Header.Set("Range", "bytes=2-4")
+			w := httptest.NewRecorder()
+			s.ServeHTTP(w, r)
+			if method == "HEAD" {
+				if w.Code != 200 || w.Body.Len() != 0 || store.bytes != before {
+					t.Fatal("HEAD read body", w)
+				}
+			} else if streaming {
+				if w.Code != 200 || w.Body.String() != "0123456789" || w.Header().Get("Accept-Ranges") != "" {
+					t.Fatal("stream fallback", w)
+				}
+			} else {
+				if w.Code != 206 || w.Body.String() != "234" || store.bytes-before != 3 {
+					t.Fatal("range buffered full body", w)
+				}
+			}
+			if w.Header().Get("Cache-Control") != "private, no-store" {
+				t.Fatal("missing cache policy")
+			}
+		}
+		if !streaming {
+			for _, h := range []http.Header{{"Range": {"bytes=99-100"}}, {"If-Modified-Since": {"Fri, 01 Jan 2100 00:00:00 GMT"}}} {
+				r := httptest.NewRequest("GET", link.URL, nil)
+				r.Header = h
+				w := httptest.NewRecorder()
+				s.ServeHTTP(w, r)
+				if w.Code != 416 && w.Code != 304 {
+					t.Fatal(w.Code)
+				}
+				if w.Header().Get("Cache-Control") != "private, no-store" {
+					t.Fatal("cache policy lost on error/conditional")
+				}
+			}
+		}
+	}
+}
--- a/storage/s3/read.go
+++ b/storage/s3/read.go
@@ -0,0 +1,53 @@
+package s3
+
+import (
+	"context"
+	"errors"
+	"net/url"
+	"strconv"
+	"time"
+
+	"git.yuntuo.hk/k2safe/go-omni/storage"
+)
+
+func (s *Store) PresignGetWithOptions(ctx context.Context, key string, ttl time.Duration, options storage.ReadOptions) (storage.ReadLink, error) {
+	if err := storage.Check(ctx, key); err != nil {
+		return storage.ReadLink{}, err
+	}
+	if ttl < time.Second || ttl > time.Hour {
+		return storage.ReadLink{}, errors.New("storage/s3: TTL must be 1s..1h")
+	}
+	headers, err := options.ResponseHeaders()
+	if err != nil {
+		return storage.ReadLink{}, err
+	}
+	query := url.Values{"response-content-disposition": {headers.Get("Content-Disposition")}, "response-cache-control": {headers.Get("Cache-Control")}}
+	if contentType := headers.Get("Content-Type"); contentType != "" {
+		query.Set("response-content-type", contentType)
+	}
+	u, err := s.client.PresignedGetObject(ctx, s.bucket, key, ttl, query)
+	if err != nil {
+		return storage.ReadLink{}, err
+	}
+	// Derive the exact expiry from the SDK's signed URL, not a second clock read
+	// around credential discovery or bucket-region lookup.
+	q := u.Query()
+	var expires time.Time
+	if q.Get("X-Amz-Signature") != "" {
+		start, e := time.Parse("20060102T150405Z", q.Get("X-Amz-Date"))
+		seconds, e2 := strconv.ParseInt(q.Get("X-Amz-Expires"), 10, 64)
+		if e != nil || e2 != nil || seconds < 1 || seconds > 3600 {
+			return storage.ReadLink{}, errors.New("storage/s3: invalid signed expiry")
+		}
+		expires = start.Add(time.Duration(seconds) * time.Second)
+	} else {
+		seconds, e := strconv.ParseInt(q.Get("Expires"), 10, 64)
+		if e != nil || q.Get("Signature") == "" {
+			return storage.ReadLink{}, errors.New("storage/s3: missing signed expiry")
+		}
+		expires = time.Unix(seconds, 0).UTC()
+	}
+	return storage.ReadLink{URL: u.String(), ExpiresAt: expires}, nil
+}
+
+var _ storage.ReadPresigner = (*Store)(nil)
--- a/storage/s3/read_test.go
+++ b/storage/s3/read_test.go
@@ -0,0 +1,145 @@
+package s3
+
+import (
+	"context"
+	"io"
+	"mime"
+	"net/http"
+	"net/url"
+	"strconv"
+	"strings"
+	"testing"
+	"time"
+
+	"git.yuntuo.hk/k2safe/go-omni/storage"
+	"github.com/minio/minio-go/v7/pkg/credentials"
+)
+
+func TestReadOptionsS3AndR2(t *testing.T) {
+	for _, r2 := range []bool{false, true} {
+		cfg := Config{Endpoint: "files.example", Bucket: "testbucket", Region: "us-east-1", Secure: true, Credentials: credentials.NewStaticV4("fixtureAccess", "fixtureSecret", "")}
+		if r2 {
+			var err error
+			cfg, err = R2Config(strings.Repeat("a", 32), "testbucket", cfg.Credentials)
+			if err != nil {
+				t.Fatal(err)
+			}
+		}
+		store, err := Open(cfg)
+		if err != nil {
+			t.Fatal(err)
+		}
+		for _, options := range []storage.ReadOptions{{}, {Disposition: storage.DispositionInline, FileName: "报告.pdf", ContentType: "application/pdf"}} {
+			link, err := store.PresignGetWithOptions(context.Background(), "folder/file.pdf", 30*time.Minute, options)
+			if err != nil {
+				t.Fatal(err)
+			}
+			u, _ := url.Parse(link.URL)
+			q := u.Query()
+			kind, params, err := mime.ParseMediaType(q.Get("response-content-disposition"))
+			want := options.Disposition
+			if want == "" {
+				want = "attachment"
+			}
+			if err != nil || kind != want || params["filename"] != options.FileName || q.Get("response-content-type") != options.ContentType || q.Get("response-cache-control") != "private, no-store" || q.Get("X-Amz-Signature") == "" {
+				t.Fatal("missing response parameters", err)
+			}
+			if u.Host != cfg.Endpoint || q.Get("X-Amz-Expires") != "1800" {
+				t.Fatal("wrong endpoint/TTL")
+			}
+			start, err := time.Parse("20060102T150405Z", q.Get("X-Amz-Date"))
+			if err != nil || !link.ExpiresAt.Equal(start.Add(30*time.Minute)) {
+				t.Fatal("expiry drift", err)
+			}
+		}
+		for _, ttl := range []time.Duration{0, time.Hour + time.Nanosecond} {
+			if _, err := store.PresignGetWithOptions(context.Background(), "file", ttl, storage.ReadOptions{}); err == nil {
+				t.Fatal("invalid TTL")
+			}
+		}
+		if _, err := store.PresignGetWithOptions(context.Background(), "file", time.Minute, storage.ReadOptions{FileName: "x\r\nY: z"}); err == nil {
+			t.Fatal("invalid filename")
+		}
+		ctx, cancel := context.WithCancel(context.Background())
+		cancel()
+		if _, err := store.PresignGetWithOptions(ctx, "file", time.Minute, storage.ReadOptions{}); err != context.Canceled {
+			t.Fatal(err)
+		}
+	}
+}
+
+// Called inside the existing isolated MinIO integration. The actual provider
+// verifies signatures and rejects tampered response parameters.
+func checkReadOptionsIntegration(t *testing.T, store *Store) {
+	t.Helper()
+	ctx := context.Background()
+	data := "%PDF-1.4\nread-test\n%%EOF"
+	_, err := store.Put(ctx, "preview.pdf", strings.NewReader(data), int64(len(data)), "application/pdf")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer store.Delete(ctx, "preview.pdf")
+	for _, kind := range []string{storage.DispositionInline, storage.DispositionAttachment} {
+		link, err := store.PresignGetWithOptions(ctx, "preview.pdf", 30*time.Minute, storage.ReadOptions{Disposition: kind, FileName: "示例.pdf", ContentType: "application/pdf"})
+		if err != nil {
+			t.Fatal(err)
+		}
+		client := &http.Client{Timeout: 5 * time.Second}
+		for _, span := range []string{"", "bytes=0-7", "bytes=999-"} {
+			req, _ := http.NewRequest("GET", link.URL, nil)
+			if span != "" {
+				req.Header.Set("Range", span)
+			}
+			r, err := client.Do(req)
+			if err != nil {
+				t.Fatal(err)
+			}
+			body, err := io.ReadAll(r.Body)
+			r.Body.Close()
+			if err != nil {
+				t.Fatal(err)
+			}
+			want := 200
+			if span == "bytes=0-7" {
+				want = 206
+			}
+			if span == "bytes=999-" {
+				want = 416
+			}
+			if r.StatusCode != want {
+				t.Fatal("status", r.StatusCode)
+			}
+			if want == 416 {
+				continue
+			}
+			disposition, params, err := mime.ParseMediaType(r.Header.Get("Content-Disposition"))
+			if err != nil || disposition != kind || params["filename"] != "示例.pdf" || r.Header.Get("Content-Type") != "application/pdf" || r.Header.Get("Cache-Control") != "private, no-store" {
+				t.Fatal("provider headers", r.Header, err)
+			}
+			value := data
+			if want == 206 {
+				value = data[:8]
+			}
+			if string(body) != value || r.Header.Get("Content-Length") != strconv.Itoa(len(value)) {
+				t.Fatal("provider body")
+			}
+		}
+		for _, name := range []string{"response-content-disposition", "response-content-type", "response-cache-control", "X-Amz-Expires"} {
+			u, _ := url.Parse(link.URL)
+			q := u.Query()
+			q.Set(name, "changed")
+			if name == "X-Amz-Expires" {
+				q.Set(name, "1801")
+			}
+			u.RawQuery = q.Encode()
+			r, err := client.Get(u.String())
+			if err != nil {
+				t.Fatal(err)
+			}
+			r.Body.Close()
+			if r.StatusCode != 403 {
+				t.Fatal("tampered parameter", name, r.StatusCode)
+			}
+		}
+	}
+}
--- a/storage/s3/s3_test.go
+++ b/storage/s3/s3_test.go
@@ -84,7 +84,9 @@ func TestS3Integration(t *testing.T) {
 	if !ready {
 		t.Fatal("isolated S3 server did not start")
 	}
-	client, err := minio.New(address, &minio.Options{Creds: credentials.NewStaticV4("goOmniTest", "goOmniTestSecret", ""), Region: "us-east-1"})
+	// The contract deliberately sends malformed bodies. Avoid retry backoff
+	// exhausting its deadline; these are expected failures, not network retries.
+	client, err := minio.New(address, &minio.Options{Creds: credentials.NewStaticV4("goOmniTest", "goOmniTestSecret", ""), Region: "us-east-1", MaxRetries: 1})
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -114,6 +116,7 @@ func TestS3Integration(t *testing.T) {
 		}
 	}
 	s, _ := New(client, bucket, 64)
+	checkReadOptionsIntegration(t, s)
 	storagetest.Run(t, s)
 	s.Put(ctx, "signed", strings.NewReader("hello"), 5, "text/plain")
 	defer s.Delete(context.Background(), "signed")
--- a/storage/signed.go
+++ b/storage/signed.go
@@ -49,30 +49,88 @@ func (s *Signer) PresignGet(ctx context.Context, key string, ttl time.Duration)
 	return &u, nil
 }

-// ServeHTTP serves signed downloads as attachments. Issue links only after
+func (s *Signer) readSignature(q url.Values) string {
+	values := make(url.Values, len(q))
+	for key, value := range q {
+		if key != "signature" {
+			values[key] = value
+		}
+	}
+	mac := hmac.New(sha256.New, s.secret)
+	io.WriteString(mac, "GET-OPTIONS-v2\n"+values.Encode())
+	return base64.RawURLEncoding.EncodeToString(mac.Sum(nil))
+}
+
+func (s *Signer) PresignGetWithOptions(ctx context.Context, key string, ttl time.Duration, options ReadOptions) (ReadLink, error) {
+	if err := Check(ctx, key); err != nil {
+		return ReadLink{}, err
+	}
+	if ttl < time.Second || ttl > time.Hour {
+		return ReadLink{}, errors.New("storage: TTL must be 1s..1h")
+	}
+	headers, err := options.ResponseHeaders()
+	if err != nil {
+		return ReadLink{}, err
+	}
+	if options.Disposition == "" {
+		options.Disposition = DispositionAttachment
+	}
+	expires := s.now().Add(ttl).UTC().Truncate(time.Second)
+	q := url.Values{"v": {"2"}, "key": {key}, "expires": {strconv.FormatInt(expires.Unix(), 10)}, "disposition": {options.Disposition}, "filename": {options.FileName}, "contentType": {headers.Get("Content-Type")}}
+	q.Set("signature", s.readSignature(q))
+	u := *s.base
+	u.RawQuery = q.Encode()
+	return ReadLink{URL: u.String(), ExpiresAt: expires}, nil
+}
+
+// ServeHTTP serves signed GET/HEAD requests, with optional preview headers.
+// Seekable object bodies support Range and conditional reads; other stores keep
+// streaming full responses. No full-object buffer is used. Issue links only after
 // authorization; possession of an unexpired URL grants access to its object.
 func (s *Signer) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	if r.Method == http.MethodPut && s.uploadPolicy != nil {
 		s.serveUpload(w, r)
 		return
 	}
+	w = &readResponseWriter{ResponseWriter: w, head: r.Method == http.MethodHead}
 	if r.Method != "GET" && r.Method != "HEAD" {
 		w.Header().Set("Allow", "GET, HEAD")
 		http.Error(w, "method not allowed", 405)
 		return
 	}
 	q, err := url.ParseQuery(r.URL.RawQuery)
-	if err != nil || len(q) != 3 || len(q["key"]) != 1 || len(q["expires"]) != 1 || len(q["signature"]) != 1 {
+	keys := []string{"key", "expires", "signature"}
+	if q.Get("v") == "2" {
+		keys = append(keys, "v", "disposition", "filename", "contentType")
+	}
+	valid := err == nil && len(q) == len(keys)
+	for _, key := range keys {
+		valid = valid && len(q[key]) == 1
+	}
+	if !valid {
 		http.Error(w, "invalid link", 403)
 		return
 	}
 	key, expiry := q.Get("key"), q.Get("expires")
 	expires, err := strconv.ParseInt(expiry, 10, 64)
 	now := s.now().Unix()
-	if err != nil || expires <= now || expires > now+3600 || Check(r.Context(), key) != nil || !hmac.Equal([]byte(q.Get("signature")), []byte(s.signature(key, expiry))) {
+	expected := s.signature(key, expiry)
+	if q.Get("v") == "2" {
+		expected = s.readSignature(q)
+	}
+	if err != nil || expires <= now || expires > now+3600 || Check(r.Context(), key) != nil || !hmac.Equal([]byte(q.Get("signature")), []byte(expected)) {
 		http.Error(w, "invalid or expired link", 403)
 		return
 	}
+	options := ReadOptions{}
+	if q.Get("v") == "2" {
+		options = ReadOptions{Disposition: q.Get("disposition"), FileName: q.Get("filename"), ContentType: q.Get("contentType")}
+	}
+	headers, err := options.ResponseHeaders()
+	if err != nil {
+		http.Error(w, "invalid link", 403)
+		return
+	}
 	object, err := s.store.Get(r.Context(), key)
 	if err != nil {
 		status := 500
@@ -82,17 +140,66 @@ func (s *Signer) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		http.Error(w, "object unavailable", status)
 		return
 	}
+	if object.Body == nil {
+		http.Error(w, "object unavailable", 500)
+		return
+	}
 	defer object.Body.Close()
+	if object.Size < 0 {
+		http.Error(w, "object unavailable", 500)
+		return
+	}
 	contentType := object.ContentType
+	if options.ContentType != "" {
+		contentType = headers.Get("Content-Type")
+	}
 	if contentType == "" {
 		contentType = "application/octet-stream"
 	}
 	w.Header().Set("Content-Type", contentType)
-	w.Header().Set("Content-Disposition", "attachment")
-	w.Header().Set("X-Content-Type-Options", "nosniff")
-	w.Header().Set("Cache-Control", "private, no-store")
+	w.Header().Set("Content-Disposition", headers.Get("Content-Disposition"))
+	if body, ok := object.Body.(io.ReadSeeker); ok {
+		// Range describes a GET representation. HEAD reports full-object headers.
+		if r.Method == http.MethodHead {
+			r = r.Clone(r.Context())
+			r.Header.Del("Range")
+		}
+		http.ServeContent(w, r, "", object.ModifiedAt, body)
+		return
+	}
 	w.Header().Set("Content-Length", strconv.FormatInt(object.Size, 10))
+	w.WriteHeader(http.StatusOK)
 	if r.Method == "GET" {
 		_, _ = io.Copy(w, object.Body)
 	}
 }
+
+// ServeContent may strip cache headers on errors in newer Go versions. Restore
+// the signed-link policy at the actual write, including 304/416 and HEAD errors.
+type readResponseWriter struct {
+	http.ResponseWriter
+	head, wrote bool
+}
+
+func (w *readResponseWriter) WriteHeader(status int) {
+	if w.wrote {
+		return
+	}
+	w.wrote = true
+	w.Header().Set("Cache-Control", "private, no-store")
+	w.Header().Set("X-Content-Type-Options", "nosniff")
+	w.ResponseWriter.WriteHeader(status)
+}
+func (w *readResponseWriter) Write(p []byte) (int, error) {
+	if !w.wrote {
+		w.WriteHeader(http.StatusOK)
+	}
+	if w.head {
+		return len(p), nil
+	}
+	return w.ResponseWriter.Write(p)
+}
+func (w *readResponseWriter) Unwrap() http.ResponseWriter { return w.ResponseWriter }
+
+var _ Presigner = (*Signer)(nil)
+var _ ReadPresigner = (*Signer)(nil)