v5.3.0

feat(auth): add AWS SigV4 authentication and bucket policy support
v5.2.0
2026-02-17 16:50:04 +00:00 · 2026-02-17 16:50:04 +00:00 · 2026-02-17 16:28:50 +00:00 · 2026-02-17 16:28:50 +00:00
21 changed files with 2684 additions and 136 deletions
--- a/changelog.md
+++ b/changelog.md
@@ -1,5 +1,24 @@
 # Changelog

+## 2026-02-17 - 5.3.0 - feat(auth)
+add AWS SigV4 authentication and bucket policy support
+
+- Implement AWS SigV4 full verification (constant-time comparison, 15-minute clock skew enforcement) and expose default signing region (server.region = 'us-east-1').
+- Add IAM-style bucket policy engine with Put/Get/Delete policy APIs (GetBucketPolicy/PutBucketPolicy/DeleteBucketPolicy), wildcard action/resource matching, Allow/Deny evaluation, and on-disk persistence under .policies/{bucket}.policy.json.
+- Documentation and README expanded with policy usage, examples, API table entries, and notes about policy CRUD and behavior for anonymous/authenticated requests.
+- Rust code refactors: simplify storage/server result structs and multipart handling (removed several unused size/key/bucket fields), remove S3Error::to_response and error_xml helpers, and other internal cleanup to support new auth/policy features.
+
+## 2026-02-17 - 5.2.0 - feat(auth,policy)
+add AWS SigV4 authentication and S3 bucket policy support
+
+- Implemented real AWS SigV4 verification (HMAC-SHA256), including x-amz-date handling, clock skew enforcement and constant-time signature comparison
+- Added bucket policy model, validator and evaluation engine (Deny > Allow > NoOpinion) with a PolicyStore (RwLock cache + disk-backed .policies/*.policy.json)
+- Integrated action resolution and auth+policy pipeline into the HTTP server: authorization checks run per-request, anonymous requests are denied by default, ListAllMyBuckets requires authentication
+- Added bucket policy CRUD handlers via ?policy query parameter (GET/PUT/DELETE) and cleanup of policies on bucket deletion
+- Storage and config updates: created .policies dir and policy path helpers; default region added to server config (TS + Rust)
+- Added comprehensive tests for auth and policy behavior (policy CRUD, evaluation, per-action enforcement, auth integration)
+- Updated Rust dependencies and Cargo.toml/Cargo.lock to include hmac, sha2, hex, subtle, cpufeatures
+
 ## 2026-02-13 - 5.1.1 - fix(smarts3)
 replace TypeScript server with Rust-powered core and IPC bridge

--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
  "name": "@push.rocks/smarts3",
-  "version": "5.1.1",
+  "version": "5.3.0",
  "private": false,
  "description": "A Node.js TypeScript package to create a local S3 endpoint for simulating AWS S3 operations using mapped local directories for development and testing purposes.",
  "main": "dist_ts/index.js",
--- a/readme.hints.md
+++ b/readme.hints.md
@@ -7,7 +7,8 @@
 - TypeScript is thin IPC wrapper; all HTTP/storage/routing in Rust binary `rusts3`
 - Full S3 compatibility: PUT, GET, HEAD, DELETE for objects and buckets
 - Multipart upload support (streaming, no OOM)
- Authentication (AWS v2/v4 signature key extraction)
+- **Real AWS SigV4 authentication** (cryptographic signature verification)
+- **Bucket policies** (AWS/MinIO-compatible JSON policies, public access support)
 - CORS support
 - ListBuckets, ListObjects (v1/v2), CopyObject

@@ -15,12 +16,15 @@

 ### Rust Binary (`rust/src/`)
 - `main.rs` - Clap CLI, management mode entry
- `config.rs` - Serde config structs matching TS interfaces
+- `config.rs` - Serde config structs matching TS interfaces (includes `region`)
 - `management.rs` - IPC loop (newline-delimited JSON over stdin/stdout)
- `server.rs` - hyper 1.x HTTP server, routing, CORS, auth, all S3 handlers
- `storage.rs` - FileStore: filesystem-backed storage, multipart manager
+- `server.rs` - hyper 1.x HTTP server, routing, CORS, auth+policy pipeline, all S3 handlers
+- `storage.rs` - FileStore: filesystem-backed storage, multipart manager, `.policies/` dir
 - `xml_response.rs` - S3 XML response builders
 - `s3_error.rs` - S3 error codes with HTTP status mapping
+- `auth.rs` - AWS SigV4 signature verification (HMAC-SHA256, clock skew, constant-time compare)
+- `action.rs` - S3Action enum + request-to-IAM-action resolver + RequestContext
+- `policy.rs` - BucketPolicy model, evaluation engine (Deny > Allow > NoOpinion), PolicyStore (RwLock cache + disk)

 ### TypeScript Bridge (`ts/`)
 - `ts/index.ts` - Smarts3 class with RustBridge<TRustS3Commands>
@@ -39,6 +43,7 @@
 - Metadata: `{root}/{bucket}/{key}._S3_object.metadata.json`
 - MD5: `{root}/{bucket}/{key}._S3_object.md5`
 - Multipart: `{root}/.multipart/{upload_id}/part-{N}`
+- Policies: `{root}/.policies/{bucket}.policy.json`

 ## Build

@@ -55,6 +60,10 @@

 ## Testing

- `test/test.aws-sdk.node.ts` - AWS SDK v3 compatibility (10 tests)
+- `test/test.aws-sdk.node.ts` - AWS SDK v3 compatibility (10 tests, auth disabled, port 3337)
+- `test/test.auth.node.ts` - Auth + bucket policy integration (20 tests, auth enabled, port 3344)
+- `test/test.policy-crud.node.ts` - Policy API CRUD + validation edge cases (17 tests, port 3345)
+- `test/test.policy-eval.node.ts` - Policy evaluation: principals, actions, resources, deny-vs-allow (22 tests, port 3346)
+- `test/test.policy-actions.node.ts` - Per-action policy enforcement (15 tests, port 3347)
 - `test/test.ts` - SmartBucket integration (3 tests)
 - Run: `pnpm test` or `tstest test/test.aws-sdk.node.ts --verbose`
--- a/readme.md
+++ b/readme.md
@@ -16,7 +16,8 @@ For reporting bugs, issues, or security vulnerabilities, please visit [community
 | Range requests | ✅ Seek-based | ✅ | ❌ Full read |
 | Language | Rust + TypeScript | Go | JavaScript |
 | Multipart uploads | ✅ Full support | ✅ | ❌ |
-| Auth | AWS v2/v4 key extraction | Full IAM | Basic |
+| Auth | ✅ AWS SigV4 (full verification) | Full IAM | Basic |
+| Bucket policies | ✅ IAM-style evaluation | ✅ | ❌ |

 ### Core Features

@@ -25,7 +26,8 @@ For reporting bugs, issues, or security vulnerabilities, please visit [community
 - 📂 **Filesystem-backed storage** — buckets map to directories, objects to files
 - 📤 **Streaming multipart uploads** — large files without memory pressure
 - 🎯 **Byte-range requests** — `seek()` directly to the requested byte offset
- 🔐 **Authentication** — AWS v2/v4 signature key extraction
+- 🔐 **AWS SigV4 authentication** — full signature verification with constant-time comparison and 15-min clock skew enforcement
+- 📜 **Bucket policies** — IAM-style JSON policies with Allow/Deny evaluation, wildcard matching, and anonymous access support
 - 🌐 **CORS middleware** — configurable cross-origin support
 - 📊 **Structured logging** — tracing-based, error through debug levels
 - 🧹 **Clean slate mode** — wipe storage on startup for test isolation
@@ -73,6 +75,7 @@ const config: ISmarts3Config = {
    port: 3000,              // Default: 3000
    address: '0.0.0.0',      // Default: '0.0.0.0'
    silent: false,           // Default: false
+    region: 'us-east-1',    // Default: 'us-east-1' — used for SigV4 signing
  },
  storage: {
    directory: './my-data',  // Default: .nogit/bucketsDir
@@ -241,6 +244,56 @@ await client.send(new CompleteMultipartUploadCommand({
 }));
 ```

+## 📜 Bucket Policies
+
+smarts3 supports AWS-style bucket policies for fine-grained access control. Policies use the same IAM JSON format as real S3 — so you can develop and test your policy logic locally before deploying.
+
+When `auth.enabled` is `true`, the auth pipeline works as follows:
+1. **Authenticate** — verify the AWS SigV4 signature (anonymous requests skip this step)
+2. **Authorize** — evaluate bucket policies against the request action, resource, and caller identity
+3. **Default** — authenticated users get full access; anonymous requests are denied unless a policy explicitly allows them
+
+### Setting a Bucket Policy
+
+Use the S3 `PutBucketPolicy` API (or any S3 client that supports it):
+
+```typescript
+import { PutBucketPolicyCommand } from '@aws-sdk/client-s3';
+
+// Allow anonymous read access to all objects in a bucket
+await client.send(new PutBucketPolicyCommand({
+  Bucket: 'public-assets',
+  Policy: JSON.stringify({
+    Version: '2012-10-17',
+    Statement: [{
+      Sid: 'PublicRead',
+      Effect: 'Allow',
+      Principal: '*',
+      Action: ['s3:GetObject'],
+      Resource: ['arn:aws:s3:::public-assets/*'],
+    }],
+  }),
+}));
+```
+
+### Policy Features
+
+- **Effect**: `Allow` and `Deny` (explicit Deny always wins)
+- **Principal**: `"*"` (everyone) or `{ "AWS": ["arn:..."] }` for specific identities
+- **Action**: IAM-style actions like `s3:GetObject`, `s3:PutObject`, `s3:*`, or prefix wildcards like `s3:Get*`
+- **Resource**: ARN patterns with `*` and `?` wildcards (e.g. `arn:aws:s3:::my-bucket/*`)
+- **Persistence**: Policies survive server restarts — stored as JSON on disk alongside your data
+
+### Policy CRUD Operations
+
+| Operation | AWS SDK Command | HTTP |
+|-----------|----------------|------|
+| Get policy | `GetBucketPolicyCommand` | `GET /{bucket}?policy` |
+| Set policy | `PutBucketPolicyCommand` | `PUT /{bucket}?policy` |
+| Delete policy | `DeleteBucketPolicyCommand` | `DELETE /{bucket}?policy` |
+
+Deleting a bucket automatically removes its associated policy.
+
 ## 🧪 Testing Integration

 ```typescript
@@ -314,7 +367,8 @@ smarts3 uses a **hybrid Rust + TypeScript** architecture:
 │  ├─ S3 path-style routing      │
 │  ├─ Streaming storage layer    │
 │  ├─ Multipart manager          │
-│  ├─ CORS / Auth middleware     │
+│  ├─ SigV4 auth + policy engine │
+│  ├─ CORS middleware            │
 │  └─ S3 XML response builder   │
 ├─────────────────────────────────┤
 │  TypeScript (thin IPC wrapper)  │
@@ -347,6 +401,9 @@ smarts3 uses a **hybrid Rust + TypeScript** architecture:
 | CompleteMultipartUpload | `POST /{bucket}/{key}?uploadId` | |
 | AbortMultipartUpload | `DELETE /{bucket}/{key}?uploadId` | |
 | ListMultipartUploads | `GET /{bucket}?uploads` | |
+| GetBucketPolicy | `GET /{bucket}?policy` | |
+| PutBucketPolicy | `PUT /{bucket}?policy` | |
+| DeleteBucketPolicy | `DELETE /{bucket}?policy` | |

 ### On-Disk Format

@@ -362,6 +419,8 @@ smarts3 uses a **hybrid Rust + TypeScript** architecture:
      part-1                      # Part data files
      part-2
      ...
+  .policies/
+    {bucket}.policy.json          # Bucket policy (IAM JSON format)
 ```

 ## 🔗 Related Packages
--- a/rust/Cargo.lock
+++ b/rust/Cargo.lock
@@ -197,6 +197,15 @@ version = "0.8.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "773648b94d0e5d620f64f280777445740e61fe701025087ec8b57f45c791888b"

+[[package]]
+name = "cpufeatures"
+version = "0.2.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "59ed5838eebb26a2bb2e58f6d5b5316989ae9d08bab10e0e6d103e656d1b0280"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "crypto-common"
 version = "0.1.7"
@@ -215,6 +224,7 @@ checksum = "9ed9a281f7bc9b7576e61468ba615a66a5c8cfdff42420a70aa82701a3b1e292"
 dependencies = [
 "block-buffer",
 "crypto-common",
+ "subtle",
 ]

 [[package]]
@@ -302,6 +312,21 @@ version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2304e00983f87ffb38b55b444b5e3b60a884b5d30c0fca7d82fe33449bbe55ea"

+[[package]]
+name = "hex"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7f24254aa9a54b5c858eaee2f5bccdb46aaf0e486a595ed5fd8f86ba55232a70"
+
+[[package]]
+name = "hmac"
+version = "0.12.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6c49c37c09c17a53d937dfbb742eb3a961d65a994e6bcdcf37e7399d0cc8ab5e"
+dependencies = [
+ "digest",
+]
+
 [[package]]
 name = "http"
 version = "1.4.0"
@@ -748,6 +773,8 @@ dependencies = [
 "chrono",
 "clap",
 "futures-core",
+ "hex",
+ "hmac",
 "http-body-util",
 "hyper",
 "hyper-util",
@@ -756,6 +783,7 @@ dependencies = [
 "quick-xml",
 "serde",
 "serde_json",
+ "sha2",
 "thiserror",
 "tokio",
 "tokio-util",
@@ -820,6 +848,17 @@ dependencies = [
 "zmij",
 ]

+[[package]]
+name = "sha2"
+version = "0.10.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a7507d819769d01a365ab707794a4084392c824f54a7a6a7862f8c3d0892b283"
+dependencies = [
+ "cfg-if",
+ "cpufeatures",
+ "digest",
+]
+
 [[package]]
 name = "sharded-slab"
 version = "0.1.7"
@@ -873,6 +912,12 @@ version = "0.11.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7da8b5736845d9f2fcb837ea5d9e2628564b3b043a70948a3f0b778838c5fb4f"

+[[package]]
+name = "subtle"
+version = "2.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "13c2bddecc57b384dee18652358fb23172facb8a2c51ccc10d74c157bdea3292"
+
 [[package]]
 name = "syn"
 version = "2.0.115"
--- a/rust/Cargo.toml
+++ b/rust/Cargo.toml
@@ -28,3 +28,6 @@ percent-encoding = "2"
 url = "2"
 chrono = { version = "0.4", features = ["serde"] }
 futures-core = "0.3"
+hmac = "0.12"
+sha2 = "0.10"
+hex = "0.4"
--- a/rust/src/action.rs
+++ b/rust/src/action.rs
@@ -0,0 +1,172 @@
+use hyper::body::Incoming;
+use hyper::{Method, Request};
+use std::collections::HashMap;
+
+/// S3 actions that map to IAM permission strings.
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum S3Action {
+    ListAllMyBuckets,
+    CreateBucket,
+    DeleteBucket,
+    HeadBucket,
+    ListBucket,
+    GetObject,
+    HeadObject,
+    PutObject,
+    DeleteObject,
+    CopyObject,
+    ListBucketMultipartUploads,
+    AbortMultipartUpload,
+    InitiateMultipartUpload,
+    UploadPart,
+    CompleteMultipartUpload,
+    GetBucketPolicy,
+    PutBucketPolicy,
+    DeleteBucketPolicy,
+}
+
+impl S3Action {
+    /// Return the IAM-style action string (e.g. "s3:GetObject").
+    pub fn iam_action(&self) -> &'static str {
+        match self {
+            S3Action::ListAllMyBuckets => "s3:ListAllMyBuckets",
+            S3Action::CreateBucket => "s3:CreateBucket",
+            S3Action::DeleteBucket => "s3:DeleteBucket",
+            S3Action::HeadBucket => "s3:ListBucket",
+            S3Action::ListBucket => "s3:ListBucket",
+            S3Action::GetObject => "s3:GetObject",
+            S3Action::HeadObject => "s3:GetObject",
+            S3Action::PutObject => "s3:PutObject",
+            S3Action::DeleteObject => "s3:DeleteObject",
+            S3Action::CopyObject => "s3:PutObject",
+            S3Action::ListBucketMultipartUploads => "s3:ListBucketMultipartUploads",
+            S3Action::AbortMultipartUpload => "s3:AbortMultipartUpload",
+            S3Action::InitiateMultipartUpload => "s3:PutObject",
+            S3Action::UploadPart => "s3:PutObject",
+            S3Action::CompleteMultipartUpload => "s3:PutObject",
+            S3Action::GetBucketPolicy => "s3:GetBucketPolicy",
+            S3Action::PutBucketPolicy => "s3:PutBucketPolicy",
+            S3Action::DeleteBucketPolicy => "s3:DeleteBucketPolicy",
+        }
+    }
+}
+
+/// Context extracted from a request, used for policy evaluation.
+#[derive(Debug, Clone)]
+pub struct RequestContext {
+    pub action: S3Action,
+    pub bucket: Option<String>,
+    pub key: Option<String>,
+}
+
+impl RequestContext {
+    /// Build the ARN for this request's resource.
+    pub fn resource_arn(&self) -> String {
+        match (&self.bucket, &self.key) {
+            (Some(bucket), Some(key)) => format!("arn:aws:s3:::{}/{}", bucket, key),
+            (Some(bucket), None) => format!("arn:aws:s3:::{}", bucket),
+            _ => "arn:aws:s3:::*".to_string(),
+        }
+    }
+}
+
+/// Resolve the S3 action from an incoming HTTP request.
+pub fn resolve_action(req: &Request<Incoming>) -> RequestContext {
+    let method = req.method().clone();
+    let path = req.uri().path().to_string();
+    let query_string = req.uri().query().unwrap_or("").to_string();
+    let query = parse_query_simple(&query_string);
+
+    let segments: Vec<&str> = path
+        .trim_start_matches('/')
+        .splitn(2, '/')
+        .filter(|s| !s.is_empty())
+        .collect();
+
+    match segments.len() {
+        0 => {
+            // Root: GET / -> ListBuckets
+            RequestContext {
+                action: S3Action::ListAllMyBuckets,
+                bucket: None,
+                key: None,
+            }
+        }
+        1 => {
+            let bucket = percent_decode(segments[0]);
+            let has_policy = query.contains_key("policy");
+            let has_uploads = query.contains_key("uploads");
+
+            let action = match (&method, has_policy, has_uploads) {
+                (&Method::GET, true, _) => S3Action::GetBucketPolicy,
+                (&Method::PUT, true, _) => S3Action::PutBucketPolicy,
+                (&Method::DELETE, true, _) => S3Action::DeleteBucketPolicy,
+                (&Method::GET, _, true) => S3Action::ListBucketMultipartUploads,
+                (&Method::GET, _, _) => S3Action::ListBucket,
+                (&Method::PUT, _, _) => S3Action::CreateBucket,
+                (&Method::DELETE, _, _) => S3Action::DeleteBucket,
+                (&Method::HEAD, _, _) => S3Action::HeadBucket,
+                _ => S3Action::ListBucket,
+            };
+
+            RequestContext {
+                action,
+                bucket: Some(bucket),
+                key: None,
+            }
+        }
+        2 => {
+            let bucket = percent_decode(segments[0]);
+            let key = percent_decode(segments[1]);
+
+            let has_copy_source = req.headers().contains_key("x-amz-copy-source");
+            let has_part_number = query.contains_key("partNumber");
+            let has_upload_id = query.contains_key("uploadId");
+            let has_uploads = query.contains_key("uploads");
+
+            let action = match &method {
+                &Method::PUT if has_part_number && has_upload_id => S3Action::UploadPart,
+                &Method::PUT if has_copy_source => S3Action::CopyObject,
+                &Method::PUT => S3Action::PutObject,
+                &Method::GET => S3Action::GetObject,
+                &Method::HEAD => S3Action::HeadObject,
+                &Method::DELETE if has_upload_id => S3Action::AbortMultipartUpload,
+                &Method::DELETE => S3Action::DeleteObject,
+                &Method::POST if has_uploads => S3Action::InitiateMultipartUpload,
+                &Method::POST if has_upload_id => S3Action::CompleteMultipartUpload,
+                _ => S3Action::GetObject,
+            };
+
+            RequestContext {
+                action,
+                bucket: Some(bucket),
+                key: Some(key),
+            }
+        }
+        _ => RequestContext {
+            action: S3Action::ListAllMyBuckets,
+            bucket: None,
+            key: None,
+        },
+    }
+}
+
+fn parse_query_simple(query_string: &str) -> HashMap<String, String> {
+    let mut map = HashMap::new();
+    if query_string.is_empty() {
+        return map;
+    }
+    for pair in query_string.split('&') {
+        let mut parts = pair.splitn(2, '=');
+        let key = parts.next().unwrap_or("");
+        let value = parts.next().unwrap_or("");
+        map.insert(key.to_string(), value.to_string());
+    }
+    map
+}
+
+fn percent_decode(s: &str) -> String {
+    percent_encoding::percent_decode_str(s)
+        .decode_utf8_lossy()
+        .to_string()
+}
--- a/rust/src/auth.rs
+++ b/rust/src/auth.rs
@@ -0,0 +1,310 @@
+use hmac::{Hmac, Mac};
+use hyper::body::Incoming;
+use hyper::Request;
+use sha2::{Digest, Sha256};
+use std::collections::HashMap;
+
+use crate::config::{Credential, S3Config};
+use crate::s3_error::S3Error;
+
+type HmacSha256 = Hmac<Sha256>;
+
+/// The identity of an authenticated caller.
+#[derive(Debug, Clone)]
+pub struct AuthenticatedIdentity {
+    pub access_key_id: String,
+}
+
+/// Parsed components of an AWS4-HMAC-SHA256 Authorization header.
+struct SigV4Header {
+    access_key_id: String,
+    date_stamp: String,
+    region: String,
+    signed_headers: Vec<String>,
+    signature: String,
+}
+
+/// Verify the request's SigV4 signature. Returns the caller identity on success.
+pub fn verify_request(
+    req: &Request<Incoming>,
+    config: &S3Config,
+) -> Result<AuthenticatedIdentity, S3Error> {
+    let auth_header = req
+        .headers()
+        .get("authorization")
+        .and_then(|v| v.to_str().ok())
+        .unwrap_or("");
+
+    // Reject SigV2
+    if auth_header.starts_with("AWS ") {
+        return Err(S3Error::authorization_header_malformed());
+    }
+
+    if !auth_header.starts_with("AWS4-HMAC-SHA256") {
+        return Err(S3Error::authorization_header_malformed());
+    }
+
+    let parsed = parse_auth_header(auth_header)?;
+
+    // Look up credential
+    let credential = find_credential(&parsed.access_key_id, config)
+        .ok_or_else(S3Error::invalid_access_key_id)?;
+
+    // Get x-amz-date
+    let amz_date = req
+        .headers()
+        .get("x-amz-date")
+        .and_then(|v| v.to_str().ok())
+        .or_else(|| {
+            req.headers()
+                .get("date")
+                .and_then(|v| v.to_str().ok())
+        })
+        .ok_or_else(|| S3Error::missing_security_header("Missing x-amz-date header"))?;
+
+    // Enforce 15-min clock skew
+    check_clock_skew(amz_date)?;
+
+    // Get payload hash
+    let content_sha256 = req
+        .headers()
+        .get("x-amz-content-sha256")
+        .and_then(|v| v.to_str().ok())
+        .unwrap_or("UNSIGNED-PAYLOAD");
+
+    // Build canonical request
+    let canonical_request = build_canonical_request(req, &parsed.signed_headers, content_sha256);
+
+    // Build string to sign
+    let scope = format!(
+        "{}/{}/s3/aws4_request",
+        parsed.date_stamp, parsed.region
+    );
+    let canonical_hash = hex::encode(Sha256::digest(canonical_request.as_bytes()));
+    let string_to_sign = format!(
+        "AWS4-HMAC-SHA256\n{}\n{}\n{}",
+        amz_date, scope, canonical_hash
+    );
+
+    // Derive signing key
+    let signing_key = derive_signing_key(
+        &credential.secret_access_key,
+        &parsed.date_stamp,
+        &parsed.region,
+    );
+
+    // Compute signature
+    let computed = hmac_sha256(&signing_key, string_to_sign.as_bytes());
+    let computed_hex = hex::encode(&computed);
+
+    // Constant-time comparison
+    if !constant_time_eq(computed_hex.as_bytes(), parsed.signature.as_bytes()) {
+        return Err(S3Error::signature_does_not_match());
+    }
+
+    Ok(AuthenticatedIdentity {
+        access_key_id: parsed.access_key_id,
+    })
+}
+
+/// Parse the Authorization header into its components.
+fn parse_auth_header(header: &str) -> Result<SigV4Header, S3Error> {
+    // Format: AWS4-HMAC-SHA256 Credential=KEY/YYYYMMDD/region/s3/aws4_request, SignedHeaders=h1;h2, Signature=hex
+    let after_algo = header
+        .strip_prefix("AWS4-HMAC-SHA256")
+        .ok_or_else(S3Error::authorization_header_malformed)?
+        .trim();
+
+    let mut credential_str = None;
+    let mut signed_headers_str = None;
+    let mut signature_str = None;
+
+    for part in after_algo.split(',') {
+        let part = part.trim();
+        if let Some(val) = part.strip_prefix("Credential=") {
+            credential_str = Some(val.trim());
+        } else if let Some(val) = part.strip_prefix("SignedHeaders=") {
+            signed_headers_str = Some(val.trim());
+        } else if let Some(val) = part.strip_prefix("Signature=") {
+            signature_str = Some(val.trim());
+        }
+    }
+
+    let credential_str = credential_str
+        .ok_or_else(S3Error::authorization_header_malformed)?;
+    let signed_headers_str = signed_headers_str
+        .ok_or_else(S3Error::authorization_header_malformed)?;
+    let signature = signature_str
+        .ok_or_else(S3Error::authorization_header_malformed)?
+        .to_string();
+
+    // Parse credential: KEY/YYYYMMDD/region/s3/aws4_request
+    let cred_parts: Vec<&str> = credential_str.splitn(5, '/').collect();
+    if cred_parts.len() < 5 {
+        return Err(S3Error::authorization_header_malformed());
+    }
+
+    let access_key_id = cred_parts[0].to_string();
+    let date_stamp = cred_parts[1].to_string();
+    let region = cred_parts[2].to_string();
+
+    let signed_headers: Vec<String> = signed_headers_str
+        .split(';')
+        .map(|s| s.trim().to_lowercase())
+        .collect();
+
+    Ok(SigV4Header {
+        access_key_id,
+        date_stamp,
+        region,
+        signed_headers,
+        signature,
+    })
+}
+
+/// Find a credential by access key ID.
+fn find_credential<'a>(access_key_id: &str, config: &'a S3Config) -> Option<&'a Credential> {
+    config
+        .auth
+        .credentials
+        .iter()
+        .find(|c| c.access_key_id == access_key_id)
+}
+
+/// Check clock skew (15 minutes max).
+fn check_clock_skew(amz_date: &str) -> Result<(), S3Error> {
+    // Parse ISO 8601 basic format: YYYYMMDDTHHMMSSZ
+    let parsed = chrono::NaiveDateTime::parse_from_str(amz_date, "%Y%m%dT%H%M%SZ")
+        .map_err(|_| S3Error::authorization_header_malformed())?;
+
+    let request_time = chrono::DateTime::<chrono::Utc>::from_naive_utc_and_offset(parsed, chrono::Utc);
+    let now = chrono::Utc::now();
+    let diff = (now - request_time).num_seconds().unsigned_abs();
+
+    if diff > 15 * 60 {
+        return Err(S3Error::request_time_too_skewed());
+    }
+
+    Ok(())
+}
+
+/// Build the canonical request string.
+fn build_canonical_request(
+    req: &Request<Incoming>,
+    signed_headers: &[String],
+    payload_hash: &str,
+) -> String {
+    let method = req.method().as_str();
+    let uri_path = req.uri().path();
+
+    // Canonical URI: the path, already percent-encoded by the client
+    let canonical_uri = if uri_path.is_empty() { "/" } else { uri_path };
+
+    // Canonical query string: sorted key=value pairs
+    let canonical_query = build_canonical_query(req.uri().query().unwrap_or(""));
+
+    // Canonical headers: sorted by lowercase header name
+    let canonical_headers = build_canonical_headers(req, signed_headers);
+
+    // Signed headers string
+    let signed_headers_str = signed_headers.join(";");
+
+    // Payload hash — accept UNSIGNED-PAYLOAD and STREAMING-AWS4-HMAC-SHA256-PAYLOAD as-is
+    let effective_payload_hash = if payload_hash == "UNSIGNED-PAYLOAD"
+        || payload_hash == "STREAMING-AWS4-HMAC-SHA256-PAYLOAD"
+    {
+        payload_hash.to_string()
+    } else {
+        payload_hash.to_string()
+    };
+
+    format!(
+        "{}\n{}\n{}\n{}\n{}\n{}",
+        method,
+        canonical_uri,
+        canonical_query,
+        canonical_headers,
+        signed_headers_str,
+        effective_payload_hash
+    )
+}
+
+/// Build canonical query string (sorted key=value pairs).
+fn build_canonical_query(query: &str) -> String {
+    if query.is_empty() {
+        return String::new();
+    }
+
+    let mut pairs: Vec<(String, String)> = Vec::new();
+    for pair in query.split('&') {
+        let mut parts = pair.splitn(2, '=');
+        let key = parts.next().unwrap_or("");
+        let value = parts.next().unwrap_or("");
+        pairs.push((key.to_string(), value.to_string()));
+    }
+    pairs.sort();
+
+    pairs
+        .iter()
+        .map(|(k, v)| format!("{}={}", k, v))
+        .collect::<Vec<_>>()
+        .join("&")
+}
+
+/// Build canonical headers string.
+fn build_canonical_headers(req: &Request<Incoming>, signed_headers: &[String]) -> String {
+    let mut header_map: HashMap<String, Vec<String>> = HashMap::new();
+
+    for (name, value) in req.headers() {
+        let name_lower = name.as_str().to_lowercase();
+        if signed_headers.contains(&name_lower) {
+            if let Ok(val) = value.to_str() {
+                header_map
+                    .entry(name_lower)
+                    .or_default()
+                    .push(val.trim().to_string());
+            }
+        }
+    }
+
+    let mut result = String::new();
+    for header_name in signed_headers {
+        let values = header_map
+            .get(header_name)
+            .map(|v| v.join(","))
+            .unwrap_or_default();
+        result.push_str(header_name);
+        result.push(':');
+        result.push_str(&values);
+        result.push('\n');
+    }
+    result
+}
+
+/// Derive the signing key via 4-step HMAC chain.
+fn derive_signing_key(secret_key: &str, date_stamp: &str, region: &str) -> Vec<u8> {
+    let k_secret = format!("AWS4{}", secret_key);
+    let k_date = hmac_sha256(k_secret.as_bytes(), date_stamp.as_bytes());
+    let k_region = hmac_sha256(&k_date, region.as_bytes());
+    let k_service = hmac_sha256(&k_region, b"s3");
+    hmac_sha256(&k_service, b"aws4_request")
+}
+
+/// Compute HMAC-SHA256.
+fn hmac_sha256(key: &[u8], data: &[u8]) -> Vec<u8> {
+    let mut mac = HmacSha256::new_from_slice(key).expect("HMAC key length is always valid");
+    mac.update(data);
+    mac.finalize().into_bytes().to_vec()
+}
+
+/// Constant-time byte comparison.
+fn constant_time_eq(a: &[u8], b: &[u8]) -> bool {
+    if a.len() != b.len() {
+        return false;
+    }
+    let mut diff = 0u8;
+    for (x, y) in a.iter().zip(b.iter()) {
+        diff |= x ^ y;
+    }
+    diff == 0
+}
--- a/rust/src/config.rs
+++ b/rust/src/config.rs
@@ -18,6 +18,12 @@ pub struct ServerConfig {
    pub port: u16,
    pub address: String,
    pub silent: bool,
+    #[serde(default = "default_region")]
+    pub region: String,
+}
+
+fn default_region() -> String {
+    "us-east-1".to_string()
 }

 #[derive(Debug, Clone, Serialize, Deserialize)]
--- a/rust/src/main.rs
+++ b/rust/src/main.rs
@@ -1,5 +1,8 @@
+mod action;
+mod auth;
 mod config;
 mod management;
+mod policy;
 mod s3_error;
 mod server;
 mod storage;
--- a/rust/src/policy.rs
+++ b/rust/src/policy.rs
@@ -0,0 +1,429 @@
+use serde::{Deserialize, Deserializer, Serialize};
+use std::collections::HashMap;
+use std::path::PathBuf;
+use tokio::fs;
+use tokio::sync::RwLock;
+
+use crate::action::RequestContext;
+use crate::auth::AuthenticatedIdentity;
+use crate::s3_error::S3Error;
+
+// ============================
+// Policy data model
+// ============================
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct BucketPolicy {
+    #[serde(rename = "Version")]
+    pub version: String,
+    #[serde(rename = "Statement")]
+    pub statements: Vec<PolicyStatement>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct PolicyStatement {
+    #[serde(rename = "Sid", default, skip_serializing_if = "Option::is_none")]
+    pub sid: Option<String>,
+    #[serde(rename = "Effect")]
+    pub effect: PolicyEffect,
+    #[serde(rename = "Principal", deserialize_with = "deserialize_principal")]
+    pub principal: Principal,
+    #[serde(rename = "Action", deserialize_with = "deserialize_string_or_vec")]
+    pub action: Vec<String>,
+    #[serde(rename = "Resource", deserialize_with = "deserialize_string_or_vec")]
+    pub resource: Vec<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
+pub enum PolicyEffect {
+    Allow,
+    Deny,
+}
+
+#[derive(Debug, Clone)]
+pub enum Principal {
+    Wildcard,
+    Aws(Vec<String>),
+}
+
+impl Serialize for Principal {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        match self {
+            Principal::Wildcard => serializer.serialize_str("*"),
+            Principal::Aws(ids) => {
+                use serde::ser::SerializeMap;
+                let mut map = serializer.serialize_map(Some(1))?;
+                if ids.len() == 1 {
+                    map.serialize_entry("AWS", &ids[0])?;
+                } else {
+                    map.serialize_entry("AWS", ids)?;
+                }
+                map.end()
+            }
+        }
+    }
+}
+
+fn deserialize_principal<'de, D>(deserializer: D) -> Result<Principal, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    #[derive(Deserialize)]
+    #[serde(untagged)]
+    enum PrincipalRaw {
+        Star(String),
+        Map(HashMap<String, StringOrVec>),
+    }
+
+    let raw = PrincipalRaw::deserialize(deserializer)?;
+    match raw {
+        PrincipalRaw::Star(s) if s == "*" => Ok(Principal::Wildcard),
+        PrincipalRaw::Star(_) => Err(serde::de::Error::custom(
+            "Principal string must be \"*\"",
+        )),
+        PrincipalRaw::Map(map) => {
+            if let Some(aws) = map.get("AWS") {
+                Ok(Principal::Aws(aws.clone().into_vec()))
+            } else {
+                Err(serde::de::Error::custom("Principal map must contain \"AWS\" key"))
+            }
+        }
+    }
+}
+
+#[derive(Debug, Clone, Deserialize)]
+#[serde(untagged)]
+enum StringOrVec {
+    Single(String),
+    Multiple(Vec<String>),
+}
+
+impl StringOrVec {
+    fn into_vec(self) -> Vec<String> {
+        match self {
+            StringOrVec::Single(s) => vec![s],
+            StringOrVec::Multiple(v) => v,
+        }
+    }
+}
+
+fn deserialize_string_or_vec<'de, D>(deserializer: D) -> Result<Vec<String>, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    let raw = StringOrVec::deserialize(deserializer)?;
+    Ok(raw.into_vec())
+}
+
+// ============================
+// Policy evaluation
+// ============================
+
+#[derive(Debug, Clone, PartialEq)]
+pub enum PolicyDecision {
+    Allow,
+    Deny,
+    NoOpinion,
+}
+
+/// Evaluate a bucket policy against a request context and caller identity.
+pub fn evaluate_policy(
+    policy: &BucketPolicy,
+    ctx: &RequestContext,
+    identity: Option<&AuthenticatedIdentity>,
+) -> PolicyDecision {
+    let resource_arn = ctx.resource_arn();
+    let iam_action = ctx.action.iam_action();
+    let mut has_allow = false;
+
+    for stmt in &policy.statements {
+        // Check principal match
+        if !principal_matches(&stmt.principal, identity) {
+            continue;
+        }
+
+        // Check action match
+        if !action_matches(&stmt.action, iam_action) {
+            continue;
+        }
+
+        // Check resource match
+        if !resource_matches(&stmt.resource, &resource_arn, ctx.bucket.as_deref()) {
+            continue;
+        }
+
+        // Statement matches — apply effect
+        match stmt.effect {
+            PolicyEffect::Deny => return PolicyDecision::Deny,
+            PolicyEffect::Allow => has_allow = true,
+        }
+    }
+
+    if has_allow {
+        PolicyDecision::Allow
+    } else {
+        PolicyDecision::NoOpinion
+    }
+}
+
+/// Check if the principal matches the caller.
+fn principal_matches(principal: &Principal, identity: Option<&AuthenticatedIdentity>) -> bool {
+    match principal {
+        Principal::Wildcard => true,
+        Principal::Aws(ids) => {
+            if let Some(id) = identity {
+                ids.iter().any(|arn| {
+                    // Match against full ARN or just the access key ID
+                    arn == "*" || arn.ends_with(&id.access_key_id)
+                })
+            } else {
+                false
+            }
+        }
+    }
+}
+
+/// Check if the action matches. Supports wildcard `s3:*` and `*`.
+fn action_matches(policy_actions: &[String], request_action: &str) -> bool {
+    for pa in policy_actions {
+        if pa == "*" || pa == "s3:*" {
+            return true;
+        }
+        if pa.eq_ignore_ascii_case(request_action) {
+            return true;
+        }
+        // Simple prefix wildcard: "s3:Get*" matches "s3:GetObject"
+        if let Some(prefix) = pa.strip_suffix('*') {
+            if request_action
+                .to_lowercase()
+                .starts_with(&prefix.to_lowercase())
+            {
+                return true;
+            }
+        }
+    }
+    false
+}
+
+/// Check if the resource matches. Supports wildcard patterns.
+fn resource_matches(policy_resources: &[String], request_arn: &str, bucket: Option<&str>) -> bool {
+    for pr in policy_resources {
+        if pr == "*" {
+            return true;
+        }
+        if arn_pattern_matches(pr, request_arn) {
+            return true;
+        }
+        // Also check bucket-level ARN if the request is for an object
+        if let Some(b) = bucket {
+            let bucket_arn = format!("arn:aws:s3:::{}", b);
+            if arn_pattern_matches(pr, &bucket_arn) {
+                return true;
+            }
+        }
+    }
+    false
+}
+
+/// Simple ARN pattern matching with `*` and `?` wildcards.
+fn arn_pattern_matches(pattern: &str, value: &str) -> bool {
+    // Handle trailing /* specifically: arn:aws:s3:::bucket/* matches arn:aws:s3:::bucket/anything
+    if pattern.ends_with("/*") {
+        let prefix = &pattern[..pattern.len() - 1]; // Remove trailing *
+        if value.starts_with(prefix) {
+            return true;
+        }
+        // Also match exact bucket without trailing /
+        let bucket_only = &pattern[..pattern.len() - 2];
+        if value == bucket_only {
+            return true;
+        }
+    }
+
+    simple_wildcard_match(pattern, value)
+}
+
+fn simple_wildcard_match(pattern: &str, value: &str) -> bool {
+    let pat_bytes = pattern.as_bytes();
+    let val_bytes = value.as_bytes();
+    let mut pi = 0;
+    let mut vi = 0;
+    let mut star_pi = usize::MAX;
+    let mut star_vi = 0;
+
+    while vi < val_bytes.len() {
+        if pi < pat_bytes.len() && (pat_bytes[pi] == b'?' || pat_bytes[pi] == val_bytes[vi]) {
+            pi += 1;
+            vi += 1;
+        } else if pi < pat_bytes.len() && pat_bytes[pi] == b'*' {
+            star_pi = pi;
+            star_vi = vi;
+            pi += 1;
+        } else if star_pi != usize::MAX {
+            pi = star_pi + 1;
+            star_vi += 1;
+            vi = star_vi;
+        } else {
+            return false;
+        }
+    }
+
+    while pi < pat_bytes.len() && pat_bytes[pi] == b'*' {
+        pi += 1;
+    }
+
+    pi == pat_bytes.len()
+}
+
+// ============================
+// Policy validation
+// ============================
+
+const MAX_POLICY_SIZE: usize = 20 * 1024; // 20 KB
+
+pub fn validate_policy(json: &str) -> Result<BucketPolicy, S3Error> {
+    if json.len() > MAX_POLICY_SIZE {
+        return Err(S3Error::malformed_policy("Policy exceeds maximum size of 20KB"));
+    }
+
+    let policy: BucketPolicy =
+        serde_json::from_str(json).map_err(|e| S3Error::malformed_policy(&e.to_string()))?;
+
+    if policy.version != "2012-10-17" {
+        return Err(S3Error::malformed_policy(
+            "Policy version must be \"2012-10-17\"",
+        ));
+    }
+
+    if policy.statements.is_empty() {
+        return Err(S3Error::malformed_policy(
+            "Policy must contain at least one statement",
+        ));
+    }
+
+    for (i, stmt) in policy.statements.iter().enumerate() {
+        if stmt.action.is_empty() {
+            return Err(S3Error::malformed_policy(&format!(
+                "Statement {} has no actions",
+                i
+            )));
+        }
+        for action in &stmt.action {
+            if action != "*" && !action.starts_with("s3:") {
+                return Err(S3Error::malformed_policy(&format!(
+                    "Action \"{}\" must start with \"s3:\"",
+                    action
+                )));
+            }
+        }
+        if stmt.resource.is_empty() {
+            return Err(S3Error::malformed_policy(&format!(
+                "Statement {} has no resources",
+                i
+            )));
+        }
+        for resource in &stmt.resource {
+            if resource != "*" && !resource.starts_with("arn:aws:s3:::") {
+                return Err(S3Error::malformed_policy(&format!(
+                    "Resource \"{}\" must start with \"arn:aws:s3:::\"",
+                    resource
+                )));
+            }
+        }
+    }
+
+    Ok(policy)
+}
+
+// ============================
+// PolicyStore — in-memory cache + disk
+// ============================
+
+pub struct PolicyStore {
+    policies: RwLock<HashMap<String, BucketPolicy>>,
+    policies_dir: PathBuf,
+}
+
+impl PolicyStore {
+    pub fn new(policies_dir: PathBuf) -> Self {
+        Self {
+            policies: RwLock::new(HashMap::new()),
+            policies_dir,
+        }
+    }
+
+    /// Load all policies from disk into cache.
+    pub async fn load_from_disk(&self) -> anyhow::Result<()> {
+        let dir = &self.policies_dir;
+        if !dir.exists() {
+            return Ok(());
+        }
+
+        let mut entries = fs::read_dir(dir).await?;
+        let mut policies = HashMap::new();
+
+        while let Some(entry) = entries.next_entry().await? {
+            let name = entry.file_name().to_string_lossy().to_string();
+            if let Some(bucket) = name.strip_suffix(".policy.json") {
+                match fs::read_to_string(entry.path()).await {
+                    Ok(json) => match serde_json::from_str::<BucketPolicy>(&json) {
+                        Ok(policy) => {
+                            tracing::info!("Loaded policy for bucket: {}", bucket);
+                            policies.insert(bucket.to_string(), policy);
+                        }
+                        Err(e) => {
+                            tracing::warn!("Failed to parse policy for {}: {}", bucket, e);
+                        }
+                    },
+                    Err(e) => {
+                        tracing::warn!("Failed to read policy file {}: {}", name, e);
+                    }
+                }
+            }
+        }
+
+        let mut cache = self.policies.write().await;
+        *cache = policies;
+        Ok(())
+    }
+
+    /// Get a policy for a bucket.
+    pub async fn get_policy(&self, bucket: &str) -> Option<BucketPolicy> {
+        let cache = self.policies.read().await;
+        cache.get(bucket).cloned()
+    }
+
+    /// Store a policy for a bucket (atomic write + cache update).
+    pub async fn put_policy(&self, bucket: &str, policy: BucketPolicy) -> anyhow::Result<()> {
+        let json = serde_json::to_string_pretty(&policy)?;
+
+        // Atomic write: temp file + rename
+        let policy_path = self.policies_dir.join(format!("{}.policy.json", bucket));
+        let temp_path = self
+            .policies_dir
+            .join(format!("{}.policy.json.tmp", bucket));
+
+        fs::write(&temp_path, &json).await?;
+        fs::rename(&temp_path, &policy_path).await?;
+
+        // Update cache
+        let mut cache = self.policies.write().await;
+        cache.insert(bucket.to_string(), policy);
+
+        Ok(())
+    }
+
+    /// Delete a policy for a bucket.
+    pub async fn delete_policy(&self, bucket: &str) -> anyhow::Result<()> {
+        let policy_path = self.policies_dir.join(format!("{}.policy.json", bucket));
+        let _ = fs::remove_file(&policy_path).await;
+
+        let mut cache = self.policies.write().await;
+        cache.remove(bucket);
+
+        Ok(())
+    }
+}
--- a/rust/src/s3_error.rs
+++ b/rust/src/s3_error.rs
@@ -1,6 +1,4 @@
-use hyper::{Response, StatusCode};
-use http_body_util::Full;
-use bytes::Bytes;
+use hyper::StatusCode;

 #[derive(Debug, thiserror::Error)]
 #[error("S3Error({code}): {message}")]
@@ -51,20 +49,58 @@ impl S3Error {
        Self::new("InvalidRequest", msg, StatusCode::BAD_REQUEST)
    }

+    pub fn signature_does_not_match() -> Self {
+        Self::new(
+            "SignatureDoesNotMatch",
+            "The request signature we calculated does not match the signature you provided.",
+            StatusCode::FORBIDDEN,
+        )
+    }
+
+    pub fn invalid_access_key_id() -> Self {
+        Self::new(
+            "InvalidAccessKeyId",
+            "The AWS Access Key Id you provided does not exist in our records.",
+            StatusCode::FORBIDDEN,
+        )
+    }
+
+    pub fn request_time_too_skewed() -> Self {
+        Self::new(
+            "RequestTimeTooSkewed",
+            "The difference between the request time and the current time is too large.",
+            StatusCode::FORBIDDEN,
+        )
+    }
+
+    pub fn authorization_header_malformed() -> Self {
+        Self::new(
+            "AuthorizationHeaderMalformed",
+            "The authorization header is malformed.",
+            StatusCode::BAD_REQUEST,
+        )
+    }
+
+    pub fn missing_security_header(msg: &str) -> Self {
+        Self::new("MissingSecurityHeader", msg, StatusCode::BAD_REQUEST)
+    }
+
+    pub fn no_such_bucket_policy() -> Self {
+        Self::new(
+            "NoSuchBucketPolicy",
+            "The bucket policy does not exist.",
+            StatusCode::NOT_FOUND,
+        )
+    }
+
+    pub fn malformed_policy(msg: &str) -> Self {
+        Self::new("MalformedPolicy", msg, StatusCode::BAD_REQUEST)
+    }
+
    pub fn to_xml(&self) -> String {
        format!(
            "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<Error><Code>{}</Code><Message>{}</Message></Error>",
            self.code, self.message
        )
    }
-
-    pub fn to_response(&self, request_id: &str) -> Response<Full<Bytes>> {
-        let xml = self.to_xml();
-        Response::builder()
-            .status(self.status)
-            .header("content-type", "application/xml")
-            .header("x-amz-request-id", request_id)
-            .body(Full::new(Bytes::from(xml)))
-            .unwrap()
-    }
 }
--- a/rust/src/server.rs
+++ b/rust/src/server.rs
@@ -18,14 +18,16 @@ use tokio::sync::watch;
 use tokio_util::io::ReaderStream;
 use uuid::Uuid;

+use crate::action::{self, RequestContext, S3Action};
+use crate::auth::{self, AuthenticatedIdentity};
 use crate::config::S3Config;
+use crate::policy::{self, PolicyDecision, PolicyStore};
 use crate::s3_error::S3Error;
 use crate::storage::FileStore;
 use crate::xml_response;

 pub struct S3Server {
    store: Arc<FileStore>,
-    config: S3Config,
    shutdown_tx: watch::Sender<bool>,
    server_handle: tokio::task::JoinHandle<()>,
 }
@@ -41,6 +43,10 @@ impl S3Server {
            store.initialize().await?;
        }

+        // Initialize policy store
+        let policy_store = Arc::new(PolicyStore::new(store.policies_dir()));
+        policy_store.load_from_disk().await?;
+
        let addr: SocketAddr = format!("{}:{}", config.address(), config.server.port)
            .parse()?;

@@ -49,6 +55,7 @@ impl S3Server {

        let server_store = store.clone();
        let server_config = config.clone();
+        let server_policy_store = policy_store.clone();

        let server_handle = tokio::spawn(async move {
            loop {
@@ -61,13 +68,15 @@ impl S3Server {
                                let io = TokioIo::new(stream);
                                let store = server_store.clone();
                                let cfg = server_config.clone();
+                                let ps = server_policy_store.clone();

                                tokio::spawn(async move {
                                    let svc = service_fn(move |req: Request<Incoming>| {
                                        let store = store.clone();
                                        let cfg = cfg.clone();
+                                        let ps = ps.clone();
                                        async move {
-                                            handle_request(req, store, cfg).await
+                                            handle_request(req, store, cfg, ps).await
                                        }
                                    });

@@ -100,7 +109,6 @@ impl S3Server {

        Ok(Self {
            store,
-            config,
            shutdown_tx,
            server_handle,
        })
@@ -198,6 +206,7 @@ async fn handle_request(
    req: Request<Incoming>,
    store: Arc<FileStore>,
    config: S3Config,
+    policy_store: Arc<PolicyStore>,
 ) -> Result<Response<BoxBody>, std::convert::Infallible> {
    let request_id = Uuid::new_v4().to_string();
    let method = req.method().clone();
@@ -210,16 +219,41 @@ async fn handle_request(
        return Ok(resp);
    }

-    // Auth check
+    // Step 1: Resolve S3 action from request
+    let request_ctx = action::resolve_action(&req);
+
+    // Step 2: Auth + policy pipeline
    if config.auth.enabled {
-        if let Err(e) = check_auth(&req, &config) {
-            tracing::warn!("Auth failed: {}", e.message);
+        // Attempt authentication
+        let identity = {
+            let has_auth_header = req
+                .headers()
+                .get("authorization")
+                .and_then(|v| v.to_str().ok())
+                .map(|s| !s.is_empty())
+                .unwrap_or(false);
+
+            if has_auth_header {
+                match auth::verify_request(&req, &config) {
+                    Ok(id) => Some(id),
+                    Err(e) => {
+                        tracing::warn!("Auth failed: {}", e.message);
+                        return Ok(s3_error_response(&e, &request_id));
+                    }
+                }
+            } else {
+                None // Anonymous request
+            }
+        };
+
+        // Step 3: Authorization (policy evaluation)
+        if let Err(e) = authorize_request(&request_ctx, identity.as_ref(), &policy_store).await {
            return Ok(s3_error_response(&e, &request_id));
        }
    }

    // Route and handle
-    let mut response = match route_request(req, store, &config, &request_id).await {
+    let mut response = match route_request(req, store, &config, &request_id, &policy_store).await {
        Ok(resp) => resp,
        Err(err) => {
            if let Some(s3err) = err.downcast_ref::<S3Error>() {
@@ -249,6 +283,42 @@ async fn handle_request(
    Ok(response)
 }

+/// Authorize a request based on bucket policies and authentication state.
+async fn authorize_request(
+    ctx: &RequestContext,
+    identity: Option<&AuthenticatedIdentity>,
+    policy_store: &PolicyStore,
+) -> Result<(), S3Error> {
+    // ListAllMyBuckets requires authentication (no bucket to apply policy to)
+    if ctx.action == S3Action::ListAllMyBuckets {
+        if identity.is_none() {
+            return Err(S3Error::access_denied());
+        }
+        return Ok(());
+    }
+
+    // If there's a bucket, check its policy
+    if let Some(ref bucket) = ctx.bucket {
+        if let Some(bucket_policy) = policy_store.get_policy(bucket).await {
+            let decision = policy::evaluate_policy(&bucket_policy, ctx, identity);
+            match decision {
+                PolicyDecision::Deny => return Err(S3Error::access_denied()),
+                PolicyDecision::Allow => return Ok(()),
+                PolicyDecision::NoOpinion => {
+                    // Fall through to default behavior
+                }
+            }
+        }
+    }
+
+    // Default: authenticated users get full access, anonymous denied
+    if identity.is_none() {
+        return Err(S3Error::access_denied());
+    }
+
+    Ok(())
+}
+
 // ============================
 // Routing
 // ============================
@@ -258,6 +328,7 @@ async fn route_request(
    store: Arc<FileStore>,
    _config: &S3Config,
    request_id: &str,
+    policy_store: &Arc<PolicyStore>,
 ) -> Result<Response<BoxBody>> {
    let method = req.method().clone();
    let path = req.uri().path().to_string();
@@ -282,6 +353,17 @@ async fn route_request(
        1 => {
            // Bucket level: /{bucket}
            let bucket = percent_decode(segments[0]);
+
+            // Check for ?policy query parameter
+            if query.contains_key("policy") {
+                return match method {
+                    Method::GET => handle_get_bucket_policy(policy_store, &bucket, request_id).await,
+                    Method::PUT => handle_put_bucket_policy(req, &store, policy_store, &bucket, request_id).await,
+                    Method::DELETE => handle_delete_bucket_policy(policy_store, &bucket, request_id).await,
+                    _ => Ok(empty_response(StatusCode::METHOD_NOT_ALLOWED, request_id)),
+                };
+            }
+
            match method {
                Method::GET => {
                    if query.contains_key("uploads") {
@@ -291,7 +373,7 @@ async fn route_request(
                    }
                }
                Method::PUT => handle_create_bucket(store, &bucket, request_id).await,
-                Method::DELETE => handle_delete_bucket(store, &bucket, request_id).await,
+                Method::DELETE => handle_delete_bucket(store, &bucket, request_id, policy_store).await,
                Method::HEAD => handle_head_bucket(store, &bucket, request_id).await,
                _ => Ok(empty_response(StatusCode::METHOD_NOT_ALLOWED, request_id)),
            }
@@ -369,8 +451,11 @@ async fn handle_delete_bucket(
    store: Arc<FileStore>,
    bucket: &str,
    request_id: &str,
+    policy_store: &Arc<PolicyStore>,
 ) -> Result<Response<BoxBody>> {
    store.delete_bucket(bucket).await?;
+    // Clean up bucket policy on deletion
+    let _ = policy_store.delete_policy(bucket).await;
    Ok(empty_response(StatusCode::NO_CONTENT, request_id))
 }

@@ -577,6 +662,70 @@ async fn handle_copy_object(
    Ok(xml_response(StatusCode::OK, xml, request_id))
 }

+// ============================
+// Policy handlers
+// ============================
+
+async fn handle_get_bucket_policy(
+    policy_store: &Arc<PolicyStore>,
+    bucket: &str,
+    request_id: &str,
+) -> Result<Response<BoxBody>> {
+    match policy_store.get_policy(bucket).await {
+        Some(p) => {
+            let json = serde_json::to_string_pretty(&p)?;
+            let resp = Response::builder()
+                .status(StatusCode::OK)
+                .header("content-type", "application/json")
+                .header("x-amz-request-id", request_id)
+                .body(full_body(json))
+                .unwrap();
+            Ok(resp)
+        }
+        None => Err(S3Error::no_such_bucket_policy().into()),
+    }
+}
+
+async fn handle_put_bucket_policy(
+    req: Request<Incoming>,
+    store: &Arc<FileStore>,
+    policy_store: &Arc<PolicyStore>,
+    bucket: &str,
+    request_id: &str,
+) -> Result<Response<BoxBody>> {
+    // Verify bucket exists
+    if !store.bucket_exists(bucket).await {
+        return Err(S3Error::no_such_bucket().into());
+    }
+
+    // Read body
+    let body_bytes = req.collect().await.map_err(|e| anyhow::anyhow!("Body error: {}", e))?.to_bytes();
+    let body_str = String::from_utf8_lossy(&body_bytes);
+
+    // Validate and parse
+    let validated_policy = policy::validate_policy(&body_str)?;
+
+    // Store
+    policy_store
+        .put_policy(bucket, validated_policy)
+        .await
+        .map_err(|e| S3Error::internal_error(&e.to_string()))?;
+
+    Ok(empty_response(StatusCode::NO_CONTENT, request_id))
+}
+
+async fn handle_delete_bucket_policy(
+    policy_store: &Arc<PolicyStore>,
+    bucket: &str,
+    request_id: &str,
+) -> Result<Response<BoxBody>> {
+    policy_store
+        .delete_policy(bucket)
+        .await
+        .map_err(|e| S3Error::internal_error(&e.to_string()))?;
+    Ok(empty_response(StatusCode::NO_CONTENT, request_id))
+}
+
 // ============================
 // Multipart handlers
 // ============================
@@ -820,46 +969,3 @@ fn add_cors_headers(headers: &mut hyper::HeaderMap, config: &S3Config) {
        );
    }
 }
-
-// ============================
-// Auth
-// ============================
-
-fn check_auth(req: &Request<Incoming>, config: &S3Config) -> Result<(), S3Error> {
-    let auth_header = req
-        .headers()
-        .get("authorization")
-        .and_then(|v| v.to_str().ok())
-        .unwrap_or("");
-
-    if auth_header.is_empty() {
-        return Err(S3Error::access_denied());
-    }
-
-    // Extract access key from AWS v2 or v4 signature
-    let access_key = if auth_header.starts_with("AWS4-HMAC-SHA256") {
-        // v4: AWS4-HMAC-SHA256 Credential=KEY/date/region/s3/aws4_request, ...
-        auth_header
-            .split("Credential=")
-            .nth(1)
-            .and_then(|s| s.split('/').next())
-    } else if auth_header.starts_with("AWS ") {
-        // v2: AWS KEY:signature
-        auth_header
-            .strip_prefix("AWS ")
-            .and_then(|s| s.split(':').next())
-    } else {
-        None
-    };
-
-    let access_key = access_key.unwrap_or("");
-
-    // Check against configured credentials
-    for cred in &config.auth.credentials {
-        if cred.access_key_id == access_key {
-            return Ok(());
-        }
-    }
-
-    Err(S3Error::access_denied())
-}
--- a/rust/src/storage.rs
+++ b/rust/src/storage.rs
@@ -17,12 +17,10 @@ use crate::s3_error::S3Error;
 // ============================

 pub struct PutResult {
-    pub size: u64,
    pub md5: String,
 }

 pub struct GetResult {
-    pub key: String,
    pub size: u64,
    pub last_modified: DateTime<Utc>,
    pub md5: String,
@@ -32,7 +30,6 @@ pub struct GetResult {
 }

 pub struct HeadResult {
-    pub key: String,
    pub size: u64,
    pub last_modified: DateTime<Utc>,
    pub md5: String,
@@ -40,7 +37,6 @@ pub struct HeadResult {
 }

 pub struct CopyResult {
-    pub size: u64,
    pub md5: String,
    pub last_modified: DateTime<Utc>,
 }
@@ -69,14 +65,12 @@ pub struct BucketInfo {

 pub struct MultipartUploadInfo {
    pub upload_id: String,
-    pub bucket: String,
    pub key: String,
    pub initiated: DateTime<Utc>,
 }

 pub struct CompleteMultipartResult {
    pub etag: String,
-    pub size: u64,
 }

 // ============================
@@ -118,14 +112,20 @@ impl FileStore {

    pub async fn initialize(&self) -> Result<()> {
        fs::create_dir_all(&self.root_dir).await?;
+        fs::create_dir_all(self.policies_dir()).await?;
        Ok(())
    }

+    pub fn policies_dir(&self) -> PathBuf {
+        self.root_dir.join(".policies")
+    }
+
    pub async fn reset(&self) -> Result<()> {
        if self.root_dir.exists() {
            fs::remove_dir_all(&self.root_dir).await?;
        }
        fs::create_dir_all(&self.root_dir).await?;
+        fs::create_dir_all(self.policies_dir()).await?;
        Ok(())
    }

@@ -210,7 +210,6 @@ impl FileStore {
        let file = fs::File::create(&object_path).await?;
        let mut writer = BufWriter::new(file);
        let mut hasher = Md5::new();
-        let mut total_size: u64 = 0;

        // Stream body frames directly to file
        let mut body = body;
@@ -219,7 +218,6 @@ impl FileStore {
                Some(Ok(frame)) => {
                    if let Ok(data) = frame.into_data() {
                        hasher.update(&data);
-                        total_size += data.len() as u64;
                        writer.write_all(&data).await?;
                    }
                }
@@ -245,44 +243,6 @@ impl FileStore {
        fs::write(&metadata_path, metadata_json).await?;

        Ok(PutResult {
-            size: total_size,
-            md5: md5_hex,
-        })
-    }
-
-    pub async fn put_object_bytes(
-        &self,
-        bucket: &str,
-        key: &str,
-        data: &[u8],
-        metadata: HashMap<String, String>,
-    ) -> Result<PutResult> {
-        if !self.bucket_exists(bucket).await {
-            return Err(S3Error::no_such_bucket().into());
-        }
-
-        let object_path = self.object_path(bucket, key);
-        if let Some(parent) = object_path.parent() {
-            fs::create_dir_all(parent).await?;
-        }
-
-        let mut hasher = Md5::new();
-        hasher.update(data);
-        let md5_hex = format!("{:x}", hasher.finalize());
-
-        fs::write(&object_path, data).await?;
-
-        // Write MD5 sidecar
-        let md5_path = format!("{}.md5", object_path.display());
-        fs::write(&md5_path, &md5_hex).await?;
-
-        // Write metadata sidecar
-        let metadata_path = format!("{}.metadata.json", object_path.display());
-        let metadata_json = serde_json::to_string_pretty(&metadata)?;
-        fs::write(&metadata_path, metadata_json).await?;
-
-        Ok(PutResult {
-            size: data.len() as u64,
            md5: md5_hex,
        })
    }
@@ -316,7 +276,6 @@ impl FileStore {
        };

        Ok(GetResult {
-            key: key.to_string(),
            size,
            last_modified,
            md5,
@@ -342,7 +301,6 @@ impl FileStore {
        let metadata = self.read_metadata(&object_path).await;

        Ok(HeadResult {
-            key: key.to_string(),
            size,
            last_modified,
            md5,
@@ -429,7 +387,6 @@ impl FileStore {
        let last_modified: DateTime<Utc> = file_meta.modified()?.into();

        Ok(CopyResult {
-            size: file_meta.len(),
            md5,
            last_modified,
        })
@@ -662,7 +619,6 @@ impl FileStore {
        let dest_file = fs::File::create(&object_path).await?;
        let mut writer = BufWriter::new(dest_file);
        let mut hasher = Md5::new();
-        let mut total_size: u64 = 0;

        for (part_number, _etag) in parts {
            let part_path = upload_dir.join(format!("part-{}", part_number));
@@ -679,7 +635,6 @@ impl FileStore {
                }
                hasher.update(&buf[..n]);
                writer.write_all(&buf[..n]).await?;
-                total_size += n as u64;
            }
        }

@@ -702,7 +657,6 @@ impl FileStore {

        Ok(CompleteMultipartResult {
            etag,
-            size: total_size,
        })
    }

@@ -742,7 +696,6 @@ impl FileStore {

                        uploads.push(MultipartUploadInfo {
                            upload_id: meta.upload_id,
-                            bucket: meta.bucket,
                            key: meta.key,
                            initiated,
                        });
--- a/rust/src/xml_response.rs
+++ b/rust/src/xml_response.rs
@@ -132,15 +132,6 @@ pub fn list_objects_v2_xml(bucket: &str, result: &ListObjectsResult) -> String {
    xml
 }

-pub fn error_xml(code: &str, message: &str) -> String {
-    format!(
-        "{}\n<Error><Code>{}</Code><Message>{}</Message></Error>",
-        XML_DECL,
-        xml_escape(code),
-        xml_escape(message)
-    )
-}
-
 pub fn copy_object_result_xml(etag: &str, last_modified: &str) -> String {
    format!(
        "{}\n<CopyObjectResult>\
--- a/test/test.auth.node.ts
+++ b/test/test.auth.node.ts
@@ -0,0 +1,301 @@
+import { expect, tap } from '@git.zone/tstest/tapbundle';
+import {
+  S3Client,
+  CreateBucketCommand,
+  ListBucketsCommand,
+  PutObjectCommand,
+  GetObjectCommand,
+  DeleteObjectCommand,
+  DeleteBucketCommand,
+  PutBucketPolicyCommand,
+  GetBucketPolicyCommand,
+  DeleteBucketPolicyCommand,
+} from '@aws-sdk/client-s3';
+import { Readable } from 'stream';
+import * as smarts3 from '../ts/index.js';
+
+let testSmarts3Instance: smarts3.Smarts3;
+let authClient: S3Client;
+let wrongClient: S3Client;
+
+const TEST_PORT = 3344;
+const ACCESS_KEY = 'TESTAKID';
+const SECRET_KEY = 'TESTSECRETKEY123';
+
+async function streamToString(stream: Readable): Promise<string> {
+  const chunks: Buffer[] = [];
+  return new Promise((resolve, reject) => {
+    stream.on('data', (chunk) => chunks.push(Buffer.from(chunk)));
+    stream.on('error', reject);
+    stream.on('end', () => resolve(Buffer.concat(chunks).toString('utf8')));
+  });
+}
+
+// ============================
+// Server setup
+// ============================
+
+tap.test('should start S3 server with auth enabled', async () => {
+  testSmarts3Instance = await smarts3.Smarts3.createAndStart({
+    server: {
+      port: TEST_PORT,
+      silent: true,
+      region: 'us-east-1',
+    },
+    storage: {
+      cleanSlate: true,
+    },
+    auth: {
+      enabled: true,
+      credentials: [
+        {
+          accessKeyId: ACCESS_KEY,
+          secretAccessKey: SECRET_KEY,
+        },
+      ],
+    },
+  });
+
+  // Authenticated client with correct credentials
+  authClient = new S3Client({
+    endpoint: `http://localhost:${TEST_PORT}`,
+    region: 'us-east-1',
+    credentials: {
+      accessKeyId: ACCESS_KEY,
+      secretAccessKey: SECRET_KEY,
+    },
+    forcePathStyle: true,
+  });
+
+  // Client with wrong credentials
+  wrongClient = new S3Client({
+    endpoint: `http://localhost:${TEST_PORT}`,
+    region: 'us-east-1',
+    credentials: {
+      accessKeyId: 'WRONGKEY',
+      secretAccessKey: 'WRONGSECRET',
+    },
+    forcePathStyle: true,
+  });
+
+});
+
+// ============================
+// Authenticated CRUD
+// ============================
+
+tap.test('authenticated: should list buckets', async () => {
+  const response = await authClient.send(new ListBucketsCommand({}));
+  expect(response.$metadata.httpStatusCode).toEqual(200);
+  expect(Array.isArray(response.Buckets)).toEqual(true);
+});
+
+tap.test('authenticated: should create a bucket', async () => {
+  const response = await authClient.send(new CreateBucketCommand({ Bucket: 'auth-test-bucket' }));
+  expect(response.$metadata.httpStatusCode).toEqual(200);
+});
+
+tap.test('authenticated: should upload an object', async () => {
+  const response = await authClient.send(
+    new PutObjectCommand({
+      Bucket: 'auth-test-bucket',
+      Key: 'hello.txt',
+      Body: 'Hello authenticated world!',
+      ContentType: 'text/plain',
+    }),
+  );
+  expect(response.$metadata.httpStatusCode).toEqual(200);
+});
+
+tap.test('authenticated: should download the object', async () => {
+  const response = await authClient.send(
+    new GetObjectCommand({
+      Bucket: 'auth-test-bucket',
+      Key: 'hello.txt',
+    }),
+  );
+  expect(response.$metadata.httpStatusCode).toEqual(200);
+  const content = await streamToString(response.Body as Readable);
+  expect(content).toEqual('Hello authenticated world!');
+});
+
+// ============================
+// Wrong credentials → 403
+// ============================
+
+tap.test('wrong credentials: should fail to list buckets', async () => {
+  await expect(wrongClient.send(new ListBucketsCommand({}))).rejects.toThrow();
+});
+
+tap.test('wrong credentials: should fail to get object', async () => {
+  await expect(
+    wrongClient.send(
+      new GetObjectCommand({
+        Bucket: 'auth-test-bucket',
+        Key: 'hello.txt',
+      }),
+    ),
+  ).rejects.toThrow();
+});
+
+// ============================
+// Anonymous → 403 (no policy yet)
+// ============================
+
+tap.test('anonymous: should fail to list buckets', async () => {
+  const resp = await fetch(`http://localhost:${TEST_PORT}/`);
+  expect(resp.status).toEqual(403);
+});
+
+tap.test('anonymous: should fail to get object (no policy)', async () => {
+  const resp = await fetch(`http://localhost:${TEST_PORT}/auth-test-bucket/hello.txt`);
+  expect(resp.status).toEqual(403);
+});
+
+// ============================
+// Bucket policy: public read
+// ============================
+
+tap.test('should PUT a public-read bucket policy', async () => {
+  const policy = {
+    Version: '2012-10-17',
+    Statement: [
+      {
+        Sid: 'PublicRead',
+        Effect: 'Allow',
+        Principal: '*',
+        Action: ['s3:GetObject'],
+        Resource: [`arn:aws:s3:::auth-test-bucket/*`],
+      },
+    ],
+  };
+
+  const response = await authClient.send(
+    new PutBucketPolicyCommand({
+      Bucket: 'auth-test-bucket',
+      Policy: JSON.stringify(policy),
+    }),
+  );
+  expect(response.$metadata.httpStatusCode).toEqual(204);
+});
+
+tap.test('should GET the bucket policy', async () => {
+  const response = await authClient.send(
+    new GetBucketPolicyCommand({
+      Bucket: 'auth-test-bucket',
+    }),
+  );
+  expect(response.$metadata.httpStatusCode).toEqual(200);
+  const policy = JSON.parse(response.Policy!);
+  expect(policy.Statement[0].Sid).toEqual('PublicRead');
+});
+
+tap.test('anonymous: should GET object after public-read policy', async () => {
+  const resp = await fetch(`http://localhost:${TEST_PORT}/auth-test-bucket/hello.txt`);
+  expect(resp.status).toEqual(200);
+  const content = await resp.text();
+  expect(content).toEqual('Hello authenticated world!');
+});
+
+tap.test('anonymous: should still fail to PUT object (policy only allows GET)', async () => {
+  const resp = await fetch(`http://localhost:${TEST_PORT}/auth-test-bucket/anon-file.txt`, {
+    method: 'PUT',
+    body: 'should fail',
+  });
+  expect(resp.status).toEqual(403);
+});
+
+// ============================
+// Deny policy
+// ============================
+
+tap.test('should PUT a deny policy that blocks authenticated delete', async () => {
+  const policy = {
+    Version: '2012-10-17',
+    Statement: [
+      {
+        Sid: 'PublicRead',
+        Effect: 'Allow',
+        Principal: '*',
+        Action: ['s3:GetObject'],
+        Resource: [`arn:aws:s3:::auth-test-bucket/*`],
+      },
+      {
+        Sid: 'DenyDelete',
+        Effect: 'Deny',
+        Principal: '*',
+        Action: ['s3:DeleteObject'],
+        Resource: [`arn:aws:s3:::auth-test-bucket/*`],
+      },
+    ],
+  };
+
+  const response = await authClient.send(
+    new PutBucketPolicyCommand({
+      Bucket: 'auth-test-bucket',
+      Policy: JSON.stringify(policy),
+    }),
+  );
+  expect(response.$metadata.httpStatusCode).toEqual(204);
+});
+
+tap.test('authenticated: should be denied delete by policy', async () => {
+  await expect(
+    authClient.send(
+      new DeleteObjectCommand({
+        Bucket: 'auth-test-bucket',
+        Key: 'hello.txt',
+      }),
+    ),
+  ).rejects.toThrow();
+});
+
+// ============================
+// DELETE bucket policy
+// ============================
+
+tap.test('should DELETE the bucket policy', async () => {
+  const response = await authClient.send(
+    new DeleteBucketPolicyCommand({
+      Bucket: 'auth-test-bucket',
+    }),
+  );
+  expect(response.$metadata.httpStatusCode).toEqual(204);
+});
+
+tap.test('should GET policy → 404 after deletion', async () => {
+  await expect(
+    authClient.send(
+      new GetBucketPolicyCommand({
+        Bucket: 'auth-test-bucket',
+      }),
+    ),
+  ).rejects.toThrow();
+});
+
+// ============================
+// Cleanup
+// ============================
+
+tap.test('authenticated: delete object after policy removed', async () => {
+  const response = await authClient.send(
+    new DeleteObjectCommand({
+      Bucket: 'auth-test-bucket',
+      Key: 'hello.txt',
+    }),
+  );
+  expect(response.$metadata.httpStatusCode).toEqual(204);
+});
+
+tap.test('authenticated: delete the bucket', async () => {
+  const response = await authClient.send(
+    new DeleteBucketCommand({ Bucket: 'auth-test-bucket' }),
+  );
+  expect(response.$metadata.httpStatusCode).toEqual(204);
+});
+
+tap.test('should stop the S3 server', async () => {
+  await testSmarts3Instance.stop();
+});
+
+export default tap.start();
--- a/test/test.policy-actions.node.ts
+++ b/test/test.policy-actions.node.ts
@@ -0,0 +1,335 @@
+import { expect, tap } from '@git.zone/tstest/tapbundle';
+import {
+  S3Client,
+  CreateBucketCommand,
+  DeleteBucketCommand,
+  ListBucketsCommand,
+  ListObjectsV2Command,
+  PutObjectCommand,
+  GetObjectCommand,
+  DeleteObjectCommand,
+  CopyObjectCommand,
+  HeadBucketCommand,
+  PutBucketPolicyCommand,
+  GetBucketPolicyCommand,
+  DeleteBucketPolicyCommand,
+} from '@aws-sdk/client-s3';
+import * as smarts3 from '../ts/index.js';
+
+let testSmarts3Instance: smarts3.Smarts3;
+let authClient: S3Client;
+
+const TEST_PORT = 3347;
+const ACCESS_KEY = 'TESTAKID';
+const SECRET_KEY = 'TESTSECRETKEY123';
+const BUCKET = 'actions-bucket';
+const BASE_URL = `http://localhost:${TEST_PORT}`;
+
+async function putPolicy(statements: any[]) {
+  await authClient.send(
+    new PutBucketPolicyCommand({
+      Bucket: BUCKET,
+      Policy: JSON.stringify({ Version: '2012-10-17', Statement: statements }),
+    })
+  );
+}
+
+async function clearPolicy() {
+  await authClient.send(new DeleteBucketPolicyCommand({ Bucket: BUCKET }));
+}
+
+function denyStatement(action: string) {
+  return {
+    Sid: `Deny_${action.replace(':', '_')}`,
+    Effect: 'Deny' as const,
+    Principal: '*',
+    Action: action,
+    Resource: [
+      `arn:aws:s3:::${BUCKET}`,
+      `arn:aws:s3:::${BUCKET}/*`,
+    ],
+  };
+}
+
+// ============================
+// Server setup
+// ============================
+
+tap.test('setup: start server, create bucket, upload object', async () => {
+  testSmarts3Instance = await smarts3.Smarts3.createAndStart({
+    server: { port: TEST_PORT, silent: true, region: 'us-east-1' },
+    storage: { cleanSlate: true },
+    auth: {
+      enabled: true,
+      credentials: [{ accessKeyId: ACCESS_KEY, secretAccessKey: SECRET_KEY }],
+    },
+  });
+
+  authClient = new S3Client({
+    endpoint: BASE_URL,
+    region: 'us-east-1',
+    credentials: { accessKeyId: ACCESS_KEY, secretAccessKey: SECRET_KEY },
+    forcePathStyle: true,
+  });
+
+  await authClient.send(new CreateBucketCommand({ Bucket: BUCKET }));
+  await authClient.send(
+    new PutObjectCommand({
+      Bucket: BUCKET,
+      Key: 'obj.txt',
+      Body: 'test content for actions',
+      ContentType: 'text/plain',
+    })
+  );
+});
+
+// ============================
+// Per-action deny enforcement
+// ============================
+
+tap.test('Deny s3:ListBucket → authenticated ListObjects fails', async () => {
+  await putPolicy([denyStatement('s3:ListBucket')]);
+
+  await expect(
+    authClient.send(new ListObjectsV2Command({ Bucket: BUCKET }))
+  ).rejects.toThrow();
+
+  await clearPolicy();
+});
+
+tap.test('Deny s3:CreateBucket → authenticated CreateBucket on new bucket fails', async () => {
+  // We need to create a policy on the target bucket, but the target doesn't exist yet.
+  // Instead, we use a different approach: deny on existing bucket and test HeadBucket works
+  // but for CreateBucket, use fetch to target a new bucket name with the deny check.
+  // Actually, CreateBucket has no bucket policy to evaluate against (the bucket doesn't exist yet).
+  // The deny would need to be on the bucket being created.
+  // Since the bucket doesn't exist, there's no policy to load — so CreateBucket can't be denied via policy.
+  // This is expected AWS behavior. Skip this test and note it.
+
+  // Verify CreateBucket still works (no policy can deny it since bucket doesn't exist yet)
+  await authClient.send(new CreateBucketCommand({ Bucket: 'new-test-bucket' }));
+  await authClient.send(new DeleteBucketCommand({ Bucket: 'new-test-bucket' }));
+});
+
+tap.test('Deny s3:DeleteBucket → authenticated DeleteBucket fails', async () => {
+  await putPolicy([denyStatement('s3:DeleteBucket')]);
+
+  await expect(
+    authClient.send(new DeleteBucketCommand({ Bucket: BUCKET }))
+  ).rejects.toThrow();
+
+  await clearPolicy();
+});
+
+tap.test('Deny s3:GetObject → authenticated GetObject fails', async () => {
+  await putPolicy([denyStatement('s3:GetObject')]);
+
+  await expect(
+    authClient.send(new GetObjectCommand({ Bucket: BUCKET, Key: 'obj.txt' }))
+  ).rejects.toThrow();
+
+  await clearPolicy();
+});
+
+tap.test('Deny s3:PutObject → authenticated PutObject fails', async () => {
+  await putPolicy([denyStatement('s3:PutObject')]);
+
+  await expect(
+    authClient.send(
+      new PutObjectCommand({
+        Bucket: BUCKET,
+        Key: 'new-obj.txt',
+        Body: 'should fail',
+      })
+    )
+  ).rejects.toThrow();
+
+  await clearPolicy();
+});
+
+tap.test('Deny s3:DeleteObject → authenticated DeleteObject fails', async () => {
+  await putPolicy([denyStatement('s3:DeleteObject')]);
+
+  await expect(
+    authClient.send(new DeleteObjectCommand({ Bucket: BUCKET, Key: 'obj.txt' }))
+  ).rejects.toThrow();
+
+  await clearPolicy();
+});
+
+tap.test('Deny s3:PutObject → authenticated CopyObject fails (maps to s3:PutObject)', async () => {
+  await putPolicy([denyStatement('s3:PutObject')]);
+
+  await expect(
+    authClient.send(
+      new CopyObjectCommand({
+        Bucket: BUCKET,
+        Key: 'obj-copy.txt',
+        CopySource: `${BUCKET}/obj.txt`,
+      })
+    )
+  ).rejects.toThrow();
+
+  await clearPolicy();
+});
+
+tap.test('Deny s3:GetBucketPolicy → authenticated GetBucketPolicy fails', async () => {
+  // First put a policy that denies GetBucketPolicy
+  // We need to be careful: put the deny policy, then try to get it
+  await putPolicy([denyStatement('s3:GetBucketPolicy')]);
+
+  await expect(
+    authClient.send(new GetBucketPolicyCommand({ Bucket: BUCKET }))
+  ).rejects.toThrow();
+
+  // Clear using direct delete (which isn't denied)
+  await clearPolicy();
+});
+
+tap.test('Deny s3:PutBucketPolicy → authenticated PutBucketPolicy fails (for second policy)', async () => {
+  // First put a policy that denies PutBucketPolicy
+  await putPolicy([denyStatement('s3:PutBucketPolicy')]);
+
+  // Now try to put another policy — should fail
+  await expect(
+    authClient.send(
+      new PutBucketPolicyCommand({
+        Bucket: BUCKET,
+        Policy: JSON.stringify({
+          Version: '2012-10-17',
+          Statement: [
+            {
+              Sid: 'SomeOtherPolicy',
+              Effect: 'Allow',
+              Principal: '*',
+              Action: 's3:GetObject',
+              Resource: `arn:aws:s3:::${BUCKET}/*`,
+            },
+          ],
+        }),
+      })
+    )
+  ).rejects.toThrow();
+
+  await clearPolicy();
+});
+
+tap.test('Deny s3:DeleteBucketPolicy → authenticated DeleteBucketPolicy fails', async () => {
+  await putPolicy([denyStatement('s3:DeleteBucketPolicy')]);
+
+  await expect(
+    authClient.send(new DeleteBucketPolicyCommand({ Bucket: BUCKET }))
+  ).rejects.toThrow();
+
+  // We need another way to clean up — use fetch with auth to bypass? No, the deny is on all principals.
+  // Actually, we can't clear the policy via SDK since delete is denied.
+  // The server still denies it. We need to stop and restart or use a different mechanism.
+  // For test cleanup, just stop the server at end and it will be wiped with cleanSlate on next start.
+});
+
+tap.test('Recovery: remove deny policy → authenticated operations resume working', async () => {
+  // The previous test left a deny policy on DeleteBucketPolicy.
+  // But we can work around it by stopping/restarting or if the deny is still in place.
+  // Actually, we denied s3:DeleteBucketPolicy but NOT s3:PutBucketPolicy.
+  // So we can overwrite the policy with an empty-ish one, then delete.
+  await authClient.send(
+    new PutBucketPolicyCommand({
+      Bucket: BUCKET,
+      Policy: JSON.stringify({
+        Version: '2012-10-17',
+        Statement: [
+          {
+            Sid: 'AllowAll',
+            Effect: 'Allow',
+            Principal: '*',
+            Action: 's3:*',
+            Resource: [`arn:aws:s3:::${BUCKET}`, `arn:aws:s3:::${BUCKET}/*`],
+          },
+        ],
+      }),
+    })
+  );
+
+  // Now all operations should work again
+  const getResp = await authClient.send(
+    new GetObjectCommand({ Bucket: BUCKET, Key: 'obj.txt' })
+  );
+  expect(getResp.$metadata.httpStatusCode).toEqual(200);
+
+  const listResp = await authClient.send(
+    new ListObjectsV2Command({ Bucket: BUCKET })
+  );
+  expect(listResp.$metadata.httpStatusCode).toEqual(200);
+
+  await clearPolicy();
+});
+
+// ============================
+// Special cases
+// ============================
+
+tap.test('ListAllMyBuckets always requires auth → anonymous fetch to / returns 403', async () => {
+  const resp = await fetch(`${BASE_URL}/`);
+  expect(resp.status).toEqual(403);
+});
+
+tap.test('Auth disabled mode → anonymous full access works', async () => {
+  // Start a second server with auth disabled
+  const noAuthInstance = await smarts3.Smarts3.createAndStart({
+    server: { port: 3348, silent: true, region: 'us-east-1' },
+    storage: { cleanSlate: true },
+    auth: { enabled: false, credentials: [] },
+  });
+
+  // Anonymous operations should all work
+  const listResp = await fetch('http://localhost:3348/');
+  expect(listResp.status).toEqual(200);
+
+  // Create bucket via fetch
+  const createResp = await fetch('http://localhost:3348/anon-bucket', { method: 'PUT' });
+  expect(createResp.status).toEqual(200);
+
+  // Put object
+  const putResp = await fetch('http://localhost:3348/anon-bucket/file.txt', {
+    method: 'PUT',
+    body: 'hello anon',
+  });
+  expect(putResp.status).toEqual(200);
+
+  // Get object
+  const getResp = await fetch('http://localhost:3348/anon-bucket/file.txt');
+  expect(getResp.status).toEqual(200);
+  const text = await getResp.text();
+  expect(text).toEqual('hello anon');
+
+  // Delete object
+  const delObjResp = await fetch('http://localhost:3348/anon-bucket/file.txt', { method: 'DELETE' });
+  expect(delObjResp.status).toEqual(204);
+
+  // Delete bucket
+  const delBucketResp = await fetch('http://localhost:3348/anon-bucket', { method: 'DELETE' });
+  expect(delBucketResp.status).toEqual(204);
+
+  await noAuthInstance.stop();
+});
+
+// ============================
+// Teardown
+// ============================
+
+tap.test('teardown: clean up and stop server', async () => {
+  // Clean up any remaining objects
+  try {
+    await authClient.send(new DeleteObjectCommand({ Bucket: BUCKET, Key: 'obj.txt' }));
+  } catch {
+    // May already be deleted
+  }
+  try {
+    await authClient.send(new DeleteBucketCommand({ Bucket: BUCKET }));
+  } catch {
+    // May already be deleted
+  }
+  await testSmarts3Instance.stop();
+});
+
+export default tap.start();
--- a/test/test.policy-crud.node.ts
+++ b/test/test.policy-crud.node.ts
@@ -0,0 +1,252 @@
+import { expect, tap } from '@git.zone/tstest/tapbundle';
+import {
+  S3Client,
+  CreateBucketCommand,
+  DeleteBucketCommand,
+  PutBucketPolicyCommand,
+  GetBucketPolicyCommand,
+  DeleteBucketPolicyCommand,
+} from '@aws-sdk/client-s3';
+import * as smarts3 from '../ts/index.js';
+
+let testSmarts3Instance: smarts3.Smarts3;
+let authClient: S3Client;
+
+const TEST_PORT = 3345;
+const ACCESS_KEY = 'TESTAKID';
+const SECRET_KEY = 'TESTSECRETKEY123';
+const BUCKET = 'policy-crud-bucket';
+
+function makePolicy(statements: any[]) {
+  return JSON.stringify({ Version: '2012-10-17', Statement: statements });
+}
+
+const validStatement = {
+  Sid: 'Test1',
+  Effect: 'Allow',
+  Principal: '*',
+  Action: ['s3:GetObject'],
+  Resource: [`arn:aws:s3:::${BUCKET}/*`],
+};
+
+// ============================
+// Server setup
+// ============================
+
+tap.test('setup: start S3 server with auth enabled', async () => {
+  testSmarts3Instance = await smarts3.Smarts3.createAndStart({
+    server: { port: TEST_PORT, silent: true, region: 'us-east-1' },
+    storage: { cleanSlate: true },
+    auth: {
+      enabled: true,
+      credentials: [{ accessKeyId: ACCESS_KEY, secretAccessKey: SECRET_KEY }],
+    },
+  });
+
+  authClient = new S3Client({
+    endpoint: `http://localhost:${TEST_PORT}`,
+    region: 'us-east-1',
+    credentials: { accessKeyId: ACCESS_KEY, secretAccessKey: SECRET_KEY },
+    forcePathStyle: true,
+  });
+});
+
+tap.test('setup: create bucket', async () => {
+  await authClient.send(new CreateBucketCommand({ Bucket: BUCKET }));
+});
+
+// ============================
+// CRUD tests
+// ============================
+
+tap.test('GET policy on bucket with no policy → throws (NoSuchBucketPolicy)', async () => {
+  await expect(
+    authClient.send(new GetBucketPolicyCommand({ Bucket: BUCKET }))
+  ).rejects.toThrow();
+});
+
+tap.test('PUT valid policy → 204', async () => {
+  const response = await authClient.send(
+    new PutBucketPolicyCommand({
+      Bucket: BUCKET,
+      Policy: makePolicy([validStatement]),
+    })
+  );
+  expect(response.$metadata.httpStatusCode).toEqual(204);
+});
+
+tap.test('GET policy back → returns matching JSON', async () => {
+  const response = await authClient.send(
+    new GetBucketPolicyCommand({ Bucket: BUCKET })
+  );
+  expect(response.$metadata.httpStatusCode).toEqual(200);
+  const policy = JSON.parse(response.Policy!);
+  expect(policy.Version).toEqual('2012-10-17');
+  expect(policy.Statement[0].Sid).toEqual('Test1');
+  expect(policy.Statement[0].Effect).toEqual('Allow');
+});
+
+tap.test('PUT updated policy (overwrite) → 204, GET returns new version', async () => {
+  const updatedStatement = {
+    Sid: 'Updated',
+    Effect: 'Deny',
+    Principal: '*',
+    Action: ['s3:DeleteObject'],
+    Resource: [`arn:aws:s3:::${BUCKET}/*`],
+  };
+
+  const putResp = await authClient.send(
+    new PutBucketPolicyCommand({
+      Bucket: BUCKET,
+      Policy: makePolicy([updatedStatement]),
+    })
+  );
+  expect(putResp.$metadata.httpStatusCode).toEqual(204);
+
+  const getResp = await authClient.send(
+    new GetBucketPolicyCommand({ Bucket: BUCKET })
+  );
+  const policy = JSON.parse(getResp.Policy!);
+  expect(policy.Statement[0].Sid).toEqual('Updated');
+  expect(policy.Statement[0].Effect).toEqual('Deny');
+});
+
+tap.test('DELETE policy → 204', async () => {
+  const response = await authClient.send(
+    new DeleteBucketPolicyCommand({ Bucket: BUCKET })
+  );
+  expect(response.$metadata.httpStatusCode).toEqual(204);
+});
+
+tap.test('DELETE policy again (idempotent) → 204', async () => {
+  const response = await authClient.send(
+    new DeleteBucketPolicyCommand({ Bucket: BUCKET })
+  );
+  expect(response.$metadata.httpStatusCode).toEqual(204);
+});
+
+tap.test('GET policy after delete → throws', async () => {
+  await expect(
+    authClient.send(new GetBucketPolicyCommand({ Bucket: BUCKET }))
+  ).rejects.toThrow();
+});
+
+tap.test('PUT policy on non-existent bucket → throws (NoSuchBucket)', async () => {
+  await expect(
+    authClient.send(
+      new PutBucketPolicyCommand({
+        Bucket: 'nonexistent-bucket-xyz',
+        Policy: makePolicy([validStatement]),
+      })
+    )
+  ).rejects.toThrow();
+});
+
+tap.test('PUT invalid JSON → throws (MalformedPolicy)', async () => {
+  await expect(
+    authClient.send(
+      new PutBucketPolicyCommand({
+        Bucket: BUCKET,
+        Policy: '{not valid json!!!',
+      })
+    )
+  ).rejects.toThrow();
+});
+
+tap.test('PUT policy with wrong version → throws (MalformedPolicy)', async () => {
+  await expect(
+    authClient.send(
+      new PutBucketPolicyCommand({
+        Bucket: BUCKET,
+        Policy: JSON.stringify({
+          Version: '2023-01-01',
+          Statement: [validStatement],
+        }),
+      })
+    )
+  ).rejects.toThrow();
+});
+
+tap.test('PUT policy with empty statements array → throws (MalformedPolicy)', async () => {
+  await expect(
+    authClient.send(
+      new PutBucketPolicyCommand({
+        Bucket: BUCKET,
+        Policy: JSON.stringify({
+          Version: '2012-10-17',
+          Statement: [],
+        }),
+      })
+    )
+  ).rejects.toThrow();
+});
+
+tap.test('PUT policy with action missing s3: prefix → throws (MalformedPolicy)', async () => {
+  await expect(
+    authClient.send(
+      new PutBucketPolicyCommand({
+        Bucket: BUCKET,
+        Policy: makePolicy([
+          {
+            Sid: 'BadAction',
+            Effect: 'Allow',
+            Principal: '*',
+            Action: ['GetObject'],
+            Resource: [`arn:aws:s3:::${BUCKET}/*`],
+          },
+        ]),
+      })
+    )
+  ).rejects.toThrow();
+});
+
+tap.test('PUT policy with resource missing arn:aws:s3::: prefix → throws (MalformedPolicy)', async () => {
+  await expect(
+    authClient.send(
+      new PutBucketPolicyCommand({
+        Bucket: BUCKET,
+        Policy: makePolicy([
+          {
+            Sid: 'BadResource',
+            Effect: 'Allow',
+            Principal: '*',
+            Action: ['s3:GetObject'],
+            Resource: ['policy-crud-bucket/*'],
+          },
+        ]),
+      })
+    )
+  ).rejects.toThrow();
+});
+
+tap.test('Bucket deletion cleans up associated policy', async () => {
+  // PUT a policy
+  await authClient.send(
+    new PutBucketPolicyCommand({
+      Bucket: BUCKET,
+      Policy: makePolicy([validStatement]),
+    })
+  );
+
+  // Delete the bucket
+  await authClient.send(new DeleteBucketCommand({ Bucket: BUCKET }));
+
+  // Re-create the bucket
+  await authClient.send(new CreateBucketCommand({ Bucket: BUCKET }));
+
+  // GET policy should now be gone
+  await expect(
+    authClient.send(new GetBucketPolicyCommand({ Bucket: BUCKET }))
+  ).rejects.toThrow();
+});
+
+// ============================
+// Teardown
+// ============================
+
+tap.test('teardown: delete bucket and stop server', async () => {
+  await authClient.send(new DeleteBucketCommand({ Bucket: BUCKET }));
+  await testSmarts3Instance.stop();
+});
+
+export default tap.start();
--- a/test/test.policy-eval.node.ts
+++ b/test/test.policy-eval.node.ts
@@ -0,0 +1,517 @@
+import { expect, tap } from '@git.zone/tstest/tapbundle';
+import {
+  S3Client,
+  CreateBucketCommand,
+  DeleteBucketCommand,
+  PutObjectCommand,
+  GetObjectCommand,
+  DeleteObjectCommand,
+  PutBucketPolicyCommand,
+  DeleteBucketPolicyCommand,
+} from '@aws-sdk/client-s3';
+import { Readable } from 'stream';
+import * as smarts3 from '../ts/index.js';
+
+let testSmarts3Instance: smarts3.Smarts3;
+let authClient: S3Client;
+
+const TEST_PORT = 3346;
+const ACCESS_KEY = 'TESTAKID';
+const SECRET_KEY = 'TESTSECRETKEY123';
+const BUCKET = 'eval-bucket';
+const BASE_URL = `http://localhost:${TEST_PORT}`;
+
+async function streamToString(stream: Readable): Promise<string> {
+  const chunks: Buffer[] = [];
+  return new Promise((resolve, reject) => {
+    stream.on('data', (chunk) => chunks.push(Buffer.from(chunk)));
+    stream.on('error', reject);
+    stream.on('end', () => resolve(Buffer.concat(chunks).toString('utf8')));
+  });
+}
+
+async function putPolicy(statements: any[]) {
+  await authClient.send(
+    new PutBucketPolicyCommand({
+      Bucket: BUCKET,
+      Policy: JSON.stringify({ Version: '2012-10-17', Statement: statements }),
+    })
+  );
+}
+
+async function clearPolicy() {
+  await authClient.send(new DeleteBucketPolicyCommand({ Bucket: BUCKET }));
+}
+
+// ============================
+// Server setup
+// ============================
+
+tap.test('setup: start server, create bucket, upload object', async () => {
+  testSmarts3Instance = await smarts3.Smarts3.createAndStart({
+    server: { port: TEST_PORT, silent: true, region: 'us-east-1' },
+    storage: { cleanSlate: true },
+    auth: {
+      enabled: true,
+      credentials: [{ accessKeyId: ACCESS_KEY, secretAccessKey: SECRET_KEY }],
+    },
+  });
+
+  authClient = new S3Client({
+    endpoint: BASE_URL,
+    region: 'us-east-1',
+    credentials: { accessKeyId: ACCESS_KEY, secretAccessKey: SECRET_KEY },
+    forcePathStyle: true,
+  });
+
+  await authClient.send(new CreateBucketCommand({ Bucket: BUCKET }));
+  await authClient.send(
+    new PutObjectCommand({
+      Bucket: BUCKET,
+      Key: 'test-obj.txt',
+      Body: 'hello policy eval',
+      ContentType: 'text/plain',
+    })
+  );
+});
+
+// ============================
+// Principal matching
+// ============================
+
+tap.test('Principal: "*" → anonymous fetch GET succeeds', async () => {
+  await putPolicy([
+    {
+      Sid: 'PrincipalWildcard',
+      Effect: 'Allow',
+      Principal: '*',
+      Action: 's3:GetObject',
+      Resource: `arn:aws:s3:::${BUCKET}/*`,
+    },
+  ]);
+
+  const resp = await fetch(`${BASE_URL}/${BUCKET}/test-obj.txt`);
+  expect(resp.status).toEqual(200);
+  const text = await resp.text();
+  expect(text).toEqual('hello policy eval');
+  await clearPolicy();
+});
+
+tap.test('Principal: {"AWS": "*"} → anonymous GET fails, authenticated GET succeeds', async () => {
+  await putPolicy([
+    {
+      Sid: 'AwsWildcard',
+      Effect: 'Allow',
+      Principal: { AWS: '*' },
+      Action: 's3:GetObject',
+      Resource: `arn:aws:s3:::${BUCKET}/*`,
+    },
+  ]);
+
+  // Anonymous → no identity → Principal AWS:* doesn't match anonymous → NoOpinion → denied
+  const anonResp = await fetch(`${BASE_URL}/${BUCKET}/test-obj.txt`);
+  expect(anonResp.status).toEqual(403);
+
+  // Authenticated → has identity → Principal AWS:* matches → Allow
+  const authResp = await authClient.send(
+    new GetObjectCommand({ Bucket: BUCKET, Key: 'test-obj.txt' })
+  );
+  expect(authResp.$metadata.httpStatusCode).toEqual(200);
+  await clearPolicy();
+});
+
+tap.test('Principal: {"AWS": "arn:aws:iam::TESTAKID"} → authenticated GET succeeds', async () => {
+  await putPolicy([
+    {
+      Sid: 'SpecificPrincipal',
+      Effect: 'Allow',
+      Principal: { AWS: `arn:aws:iam::${ACCESS_KEY}` },
+      Action: 's3:GetObject',
+      Resource: `arn:aws:s3:::${BUCKET}/*`,
+    },
+  ]);
+
+  const resp = await authClient.send(
+    new GetObjectCommand({ Bucket: BUCKET, Key: 'test-obj.txt' })
+  );
+  expect(resp.$metadata.httpStatusCode).toEqual(200);
+  await clearPolicy();
+});
+
+tap.test('Principal: {"AWS": "arn:aws:iam::WRONGKEY"} → authenticated GET still succeeds (default allow)', async () => {
+  await putPolicy([
+    {
+      Sid: 'WrongPrincipal',
+      Effect: 'Allow',
+      Principal: { AWS: 'arn:aws:iam::WRONGKEY' },
+      Action: 's3:GetObject',
+      Resource: `arn:aws:s3:::${BUCKET}/*`,
+    },
+  ]);
+
+  // Principal doesn't match our key → NoOpinion → default allow for authenticated
+  const resp = await authClient.send(
+    new GetObjectCommand({ Bucket: BUCKET, Key: 'test-obj.txt' })
+  );
+  expect(resp.$metadata.httpStatusCode).toEqual(200);
+  await clearPolicy();
+});
+
+// ============================
+// Action matching
+// ============================
+
+tap.test('Action: "s3:*" → anonymous can GET and PUT (wildcard matches all)', async () => {
+  await putPolicy([
+    {
+      Sid: 'S3Wildcard',
+      Effect: 'Allow',
+      Principal: '*',
+      Action: 's3:*',
+      Resource: `arn:aws:s3:::${BUCKET}/*`,
+    },
+  ]);
+
+  const getResp = await fetch(`${BASE_URL}/${BUCKET}/test-obj.txt`);
+  expect(getResp.status).toEqual(200);
+
+  const putResp = await fetch(`${BASE_URL}/${BUCKET}/anon-wildcard.txt`, {
+    method: 'PUT',
+    body: 'wildcard put',
+  });
+  expect(putResp.status).toEqual(200);
+
+  // Clean up the object we created
+  await authClient.send(new DeleteObjectCommand({ Bucket: BUCKET, Key: 'anon-wildcard.txt' }));
+  await clearPolicy();
+});
+
+tap.test('Action: "*" → global wildcard matches all actions', async () => {
+  await putPolicy([
+    {
+      Sid: 'GlobalWildcard',
+      Effect: 'Allow',
+      Principal: '*',
+      Action: '*',
+      Resource: `arn:aws:s3:::${BUCKET}/*`,
+    },
+  ]);
+
+  const getResp = await fetch(`${BASE_URL}/${BUCKET}/test-obj.txt`);
+  expect(getResp.status).toEqual(200);
+
+  const putResp = await fetch(`${BASE_URL}/${BUCKET}/anon-global.txt`, {
+    method: 'PUT',
+    body: 'global wildcard',
+  });
+  expect(putResp.status).toEqual(200);
+
+  await authClient.send(new DeleteObjectCommand({ Bucket: BUCKET, Key: 'anon-global.txt' }));
+  await clearPolicy();
+});
+
+tap.test('Action: "s3:Get*" → anonymous can GET but not PUT (prefix wildcard)', async () => {
+  await putPolicy([
+    {
+      Sid: 'PrefixWildcard',
+      Effect: 'Allow',
+      Principal: '*',
+      Action: 's3:Get*',
+      Resource: `arn:aws:s3:::${BUCKET}/*`,
+    },
+  ]);
+
+  const getResp = await fetch(`${BASE_URL}/${BUCKET}/test-obj.txt`);
+  expect(getResp.status).toEqual(200);
+
+  const putResp = await fetch(`${BASE_URL}/${BUCKET}/anon-prefix.txt`, {
+    method: 'PUT',
+    body: 'should fail',
+  });
+  expect(putResp.status).toEqual(403);
+  await clearPolicy();
+});
+
+tap.test('Action: ["s3:GetObject", "s3:PutObject"] → anonymous can GET and PUT but not DELETE', async () => {
+  await putPolicy([
+    {
+      Sid: 'MultiAction',
+      Effect: 'Allow',
+      Principal: '*',
+      Action: ['s3:GetObject', 's3:PutObject'],
+      Resource: `arn:aws:s3:::${BUCKET}/*`,
+    },
+  ]);
+
+  const getResp = await fetch(`${BASE_URL}/${BUCKET}/test-obj.txt`);
+  expect(getResp.status).toEqual(200);
+
+  const putResp = await fetch(`${BASE_URL}/${BUCKET}/anon-multi.txt`, {
+    method: 'PUT',
+    body: 'multi action',
+  });
+  expect(putResp.status).toEqual(200);
+
+  const delResp = await fetch(`${BASE_URL}/${BUCKET}/anon-multi.txt`, {
+    method: 'DELETE',
+  });
+  expect(delResp.status).toEqual(403);
+
+  // Clean up
+  await authClient.send(new DeleteObjectCommand({ Bucket: BUCKET, Key: 'anon-multi.txt' }));
+  await clearPolicy();
+});
+
+// ============================
+// Resource ARN matching
+// ============================
+
+tap.test('Resource: "arn:aws:s3:::eval-bucket/*" → anonymous GET of object succeeds', async () => {
+  await putPolicy([
+    {
+      Sid: 'ResourceWildcard',
+      Effect: 'Allow',
+      Principal: '*',
+      Action: 's3:GetObject',
+      Resource: `arn:aws:s3:::${BUCKET}/*`,
+    },
+  ]);
+
+  const resp = await fetch(`${BASE_URL}/${BUCKET}/test-obj.txt`);
+  expect(resp.status).toEqual(200);
+  await clearPolicy();
+});
+
+tap.test('Resource: exact key → anonymous GET of that key succeeds, other key fails', async () => {
+  await putPolicy([
+    {
+      Sid: 'ExactResource',
+      Effect: 'Allow',
+      Principal: '*',
+      Action: 's3:GetObject',
+      Resource: `arn:aws:s3:::${BUCKET}/test-obj.txt`,
+    },
+  ]);
+
+  const goodResp = await fetch(`${BASE_URL}/${BUCKET}/test-obj.txt`);
+  expect(goodResp.status).toEqual(200);
+
+  // Other key → resource doesn't match → NoOpinion → denied for anonymous
+  const badResp = await fetch(`${BASE_URL}/${BUCKET}/nonexistent.txt`);
+  expect(badResp.status).toEqual(403);
+  await clearPolicy();
+});
+
+tap.test('Resource: wrong bucket ARN → NoOpinion → anonymous GET denied', async () => {
+  await putPolicy([
+    {
+      Sid: 'WrongBucket',
+      Effect: 'Allow',
+      Principal: '*',
+      Action: 's3:GetObject',
+      Resource: 'arn:aws:s3:::other-bucket/*',
+    },
+  ]);
+
+  const resp = await fetch(`${BASE_URL}/${BUCKET}/test-obj.txt`);
+  expect(resp.status).toEqual(403);
+  await clearPolicy();
+});
+
+tap.test('Resource: "*" → matches everything, anonymous GET succeeds', async () => {
+  await putPolicy([
+    {
+      Sid: 'StarResource',
+      Effect: 'Allow',
+      Principal: '*',
+      Action: 's3:GetObject',
+      Resource: '*',
+    },
+  ]);
+
+  const resp = await fetch(`${BASE_URL}/${BUCKET}/test-obj.txt`);
+  expect(resp.status).toEqual(200);
+  await clearPolicy();
+});
+
+// ============================
+// Deny-over-Allow priority
+// ============================
+
+tap.test('Allow + Deny same action → anonymous GET denied', async () => {
+  await putPolicy([
+    {
+      Sid: 'AllowGet',
+      Effect: 'Allow',
+      Principal: '*',
+      Action: 's3:GetObject',
+      Resource: `arn:aws:s3:::${BUCKET}/*`,
+    },
+    {
+      Sid: 'DenyGet',
+      Effect: 'Deny',
+      Principal: '*',
+      Action: 's3:GetObject',
+      Resource: `arn:aws:s3:::${BUCKET}/*`,
+    },
+  ]);
+
+  const resp = await fetch(`${BASE_URL}/${BUCKET}/test-obj.txt`);
+  expect(resp.status).toEqual(403);
+  await clearPolicy();
+});
+
+tap.test('Allow s3:* + Deny s3:DeleteObject → anonymous GET succeeds, DELETE denied', async () => {
+  await putPolicy([
+    {
+      Sid: 'AllowAll',
+      Effect: 'Allow',
+      Principal: '*',
+      Action: 's3:*',
+      Resource: `arn:aws:s3:::${BUCKET}/*`,
+    },
+    {
+      Sid: 'DenyDelete',
+      Effect: 'Deny',
+      Principal: '*',
+      Action: 's3:DeleteObject',
+      Resource: `arn:aws:s3:::${BUCKET}/*`,
+    },
+  ]);
+
+  const getResp = await fetch(`${BASE_URL}/${BUCKET}/test-obj.txt`);
+  expect(getResp.status).toEqual(200);
+
+  const delResp = await fetch(`${BASE_URL}/${BUCKET}/test-obj.txt`, { method: 'DELETE' });
+  expect(delResp.status).toEqual(403);
+  await clearPolicy();
+});
+
+tap.test('Statement order does not matter: Deny first, Allow second → still denied', async () => {
+  await putPolicy([
+    {
+      Sid: 'DenyFirst',
+      Effect: 'Deny',
+      Principal: '*',
+      Action: 's3:GetObject',
+      Resource: `arn:aws:s3:::${BUCKET}/*`,
+    },
+    {
+      Sid: 'AllowSecond',
+      Effect: 'Allow',
+      Principal: '*',
+      Action: 's3:GetObject',
+      Resource: `arn:aws:s3:::${BUCKET}/*`,
+    },
+  ]);
+
+  const resp = await fetch(`${BASE_URL}/${BUCKET}/test-obj.txt`);
+  expect(resp.status).toEqual(403);
+  await clearPolicy();
+});
+
+// ============================
+// NoOpinion fallback
+// ============================
+
+tap.test('NoOpinion: policy allows PutObject only → authenticated GET falls through (default allow)', async () => {
+  await putPolicy([
+    {
+      Sid: 'AllowPutOnly',
+      Effect: 'Allow',
+      Principal: '*',
+      Action: 's3:PutObject',
+      Resource: `arn:aws:s3:::${BUCKET}/*`,
+    },
+  ]);
+
+  // Authenticated → NoOpinion → default allow
+  const resp = await authClient.send(
+    new GetObjectCommand({ Bucket: BUCKET, Key: 'test-obj.txt' })
+  );
+  expect(resp.$metadata.httpStatusCode).toEqual(200);
+  await clearPolicy();
+});
+
+tap.test('NoOpinion: same policy → anonymous GET falls through → default deny (403)', async () => {
+  await putPolicy([
+    {
+      Sid: 'AllowPutOnly',
+      Effect: 'Allow',
+      Principal: '*',
+      Action: 's3:PutObject',
+      Resource: `arn:aws:s3:::${BUCKET}/*`,
+    },
+  ]);
+
+  // Anonymous → NoOpinion for GetObject → default deny
+  const resp = await fetch(`${BASE_URL}/${BUCKET}/test-obj.txt`);
+  expect(resp.status).toEqual(403);
+  await clearPolicy();
+});
+
+// ============================
+// IAM action mapping
+// ============================
+
+tap.test('Policy allows s3:GetObject → anonymous HEAD object succeeds (HeadObject maps to s3:GetObject)', async () => {
+  await putPolicy([
+    {
+      Sid: 'AllowGet',
+      Effect: 'Allow',
+      Principal: '*',
+      Action: 's3:GetObject',
+      Resource: `arn:aws:s3:::${BUCKET}/*`,
+    },
+  ]);
+
+  const resp = await fetch(`${BASE_URL}/${BUCKET}/test-obj.txt`, { method: 'HEAD' });
+  expect(resp.status).toEqual(200);
+  await clearPolicy();
+});
+
+tap.test('Policy allows s3:ListBucket → anonymous HEAD bucket succeeds', async () => {
+  await putPolicy([
+    {
+      Sid: 'AllowList',
+      Effect: 'Allow',
+      Principal: '*',
+      Action: 's3:ListBucket',
+      Resource: `arn:aws:s3:::${BUCKET}`,
+    },
+  ]);
+
+  const resp = await fetch(`${BASE_URL}/${BUCKET}`, { method: 'HEAD' });
+  expect(resp.status).toEqual(200);
+  await clearPolicy();
+});
+
+tap.test('Policy allows s3:ListBucket → anonymous GET bucket (list objects) succeeds', async () => {
+  await putPolicy([
+    {
+      Sid: 'AllowList',
+      Effect: 'Allow',
+      Principal: '*',
+      Action: 's3:ListBucket',
+      Resource: `arn:aws:s3:::${BUCKET}`,
+    },
+  ]);
+
+  const resp = await fetch(`${BASE_URL}/${BUCKET}`);
+  expect(resp.status).toEqual(200);
+  const text = await resp.text();
+  expect(text).toInclude('ListBucketResult');
+  await clearPolicy();
+});
+
+// ============================
+// Teardown
+// ============================
+
+tap.test('teardown: clean up and stop server', async () => {
+  await authClient.send(new DeleteObjectCommand({ Bucket: BUCKET, Key: 'test-obj.txt' }));
+  await authClient.send(new DeleteBucketCommand({ Bucket: BUCKET }));
+  await testSmarts3Instance.stop();
+});
+
+export default tap.start();
--- a/ts/00_commitinfo_data.ts
+++ b/ts/00_commitinfo_data.ts
@@ -3,6 +3,6 @@
 */
 export const commitinfo = {
  name: '@push.rocks/smarts3',
-  version: '5.1.1',
+  version: '5.3.0',
  description: 'A Node.js TypeScript package to create a local S3 endpoint for simulating AWS S3 operations using mapped local directories for development and testing purposes.'
 }
--- a/ts/index.ts
+++ b/ts/index.ts
@@ -58,6 +58,7 @@ export interface IServerConfig {
  port?: number;
  address?: string;
  silent?: boolean;
+  region?: string;
 }

 /**
@@ -89,6 +90,7 @@ const DEFAULT_CONFIG: ISmarts3Config = {
    port: 3000,
    address: '0.0.0.0',
    silent: false,
+    region: 'us-east-1',
  },
  storage: {
    directory: paths.bucketsDir,
Author	SHA1	Message	Date
Juergen Kunz	d437ffc226	v5.3.0 Some checks failed Default (tags) / security (push) Successful in 37s Details Default (tags) / test (push) Failing after 26s Details Default (tags) / release (push) Has been skipped Details Default (tags) / metadata (push) Has been skipped Details	2026-02-17 16:50:04 +00:00
Juergen Kunz	e36758f183	feat(auth): add AWS SigV4 authentication and bucket policy support	2026-02-17 16:50:04 +00:00
Juergen Kunz	adf45dce2d	v5.2.0 Some checks failed Default (tags) / security (push) Successful in 40s Details Default (tags) / test (push) Failing after 27s Details Default (tags) / release (push) Has been skipped Details Default (tags) / metadata (push) Has been skipped Details	2026-02-17 16:28:50 +00:00
Juergen Kunz	eb232b6e8e	feat(auth,policy): add AWS SigV4 authentication and S3 bucket policy support	2026-02-17 16:28:50 +00:00