s3: combine all signature verification checks into a single function (#7330)

6 files changed, 592 insertions, 332 deletions

diff --git a/weed/s3api/auth_signature_v4.go b/weed/s3api/auth_signature_v4.go
index 05e5c7b5f..3a8e59392 100644
--- a/weed/s3api/auth_signature_v4.go
+++ b/weed/s3api/auth_signature_v4.go
@@ -25,7 +25,6 @@ import (
 	"encoding/hex"
 	"io"
 	"net/http"
-	"path"
 	"regexp"
 	"sort"
 	"strconv"
@@ -33,17 +32,20 @@ import (
 	"time"
 	"unicode/utf8"
 
+	"github.com/seaweedfs/seaweedfs/weed/glog"
+
 	"github.com/seaweedfs/seaweedfs/weed/s3api/s3_constants"
 	"github.com/seaweedfs/seaweedfs/weed/s3api/s3err"
 )
 
 func (iam *IdentityAccessManagement) reqSignatureV4Verify(r *http.Request) (*Identity, s3err.ErrorCode) {
-	sha256sum := getContentSha256Cksum(r)
 	switch {
 	case isRequestSignatureV4(r):
-		return iam.doesSignatureMatch(sha256sum, r)
+		identity, _, errCode := iam.doesSignatureMatch(r)
+		return identity, errCode
 	case isRequestPresignedSignatureV4(r):
-		return iam.doesPresignedSignatureMatch(sha256sum, r)
+		identity, _, errCode := iam.doesPresignedSignatureMatch(r)
+		return identity, errCode
 	}
 	return nil, s3err.ErrAccessDenied
 }
@@ -154,236 +156,298 @@ func parseSignV4(v4Auth string) (sv signValues, aec s3err.ErrorCode) {
 	return signV4Values, s3err.ErrNone
 }
 
-// doesSignatureMatch verifies the request signature.
-func (iam *IdentityAccessManagement) doesSignatureMatch(hashedPayload string, r *http.Request) (*Identity, s3err.ErrorCode) {
-
-	// Copy request
-	req := *r
+// buildPathWithForwardedPrefix combines forwarded prefix with URL path while preserving S3 key semantics.
+// This function avoids path.Clean which would collapse "//" and dot segments, breaking S3 signatures.
+// It only normalizes the join boundary to avoid double slashes between prefix and path.
+func buildPathWithForwardedPrefix(forwardedPrefix, urlPath string) string {
+	if forwardedPrefix == "" {
+		return urlPath
+	}
+	// Ensure single leading slash on prefix
+	if !strings.HasPrefix(forwardedPrefix, "/") {
+		forwardedPrefix = "/" + forwardedPrefix
+	}
+	// Join without collapsing interior segments; only fix a double slash at the boundary
+	var joined string
+	if strings.HasSuffix(forwardedPrefix, "/") && strings.HasPrefix(urlPath, "/") {
+		joined = forwardedPrefix + urlPath[1:]
+	} else if !strings.HasSuffix(forwardedPrefix, "/") && !strings.HasPrefix(urlPath, "/") {
+		joined = forwardedPrefix + "/" + urlPath
+	} else {
+		joined = forwardedPrefix + urlPath
+	}
+	// Trailing slash semantics inherited from urlPath (already present if needed)
+	return joined
+}
 
-	// Save authorization header.
-	v4Auth := req.Header.Get("Authorization")
+// v4AuthInfo holds the parsed authentication data from a request,
+// whether it's from the Authorization header or presigned URL query parameters.
+type v4AuthInfo struct {
+	Signature     string
+	AccessKey     string
+	SignedHeaders []string
+	Date          time.Time
+	Region        string
+	Service       string
+	Scope         string
+	HashedPayload string
+	IsPresigned   bool
+}
 
-	// Parse signature version '4' header.
-	signV4Values, errCode := parseSignV4(v4Auth)
+// verifyV4Signature is the single entry point for verifying any AWS Signature V4 request.
+// It handles standard requests, presigned URLs, and the seed signature for streaming uploads.
+func (iam *IdentityAccessManagement) verifyV4Signature(r *http.Request, shouldCheckPermissions bool) (identity *Identity, credential *Credential, calculatedSignature string, authInfo *v4AuthInfo, errCode s3err.ErrorCode) {
+	// 1. Extract authentication information from header or query parameters
+	authInfo, errCode = extractV4AuthInfo(r)
 	if errCode != s3err.ErrNone {
-		return nil, errCode
-	}
-
-	// Compute payload hash for non-S3 services
-	if signV4Values.Credential.scope.service != "s3" && hashedPayload == emptySHA256 && r.Body != nil {
-		var err error
-		hashedPayload, err = streamHashRequestBody(r, iamRequestBodyLimit)
-		if err != nil {
-			return nil, s3err.ErrInternalError
-		}
+		return nil, nil, "", nil, errCode
 	}
 
-	// Extract all the signed headers along with its values.
-	extractedSignedHeaders, errCode := extractSignedHeaders(signV4Values.SignedHeaders, r)
-	if errCode != s3err.ErrNone {
-		return nil, errCode
+	// 2. Lookup user and credentials
+	identity, cred, found := iam.lookupByAccessKey(authInfo.AccessKey)
+	if !found {
+		return nil, nil, "", nil, s3err.ErrInvalidAccessKeyID
 	}
 
-	cred := signV4Values.Credential
-	identity, foundCred, found := iam.lookupByAccessKey(cred.accessKey)
-	if !found {
-		return nil, s3err.ErrInvalidAccessKeyID
+	// 3. Perform permission check
+	if shouldCheckPermissions {
+		bucket, object := s3_constants.GetBucketAndObject(r)
+		action := s3_constants.ACTION_READ
+		if r.Method != http.MethodGet && r.Method != http.MethodHead {
+			action = s3_constants.ACTION_WRITE
+		}
+		if !identity.canDo(Action(action), bucket, object) {
+			return nil, nil, "", nil, s3err.ErrAccessDenied
+		}
 	}
 
-	// Extract date, if not present throw error.
-	var dateStr string
-	if dateStr = req.Header.Get("x-amz-date"); dateStr == "" {
-		if dateStr = r.Header.Get("Date"); dateStr == "" {
-			return nil, s3err.ErrMissingDateHeader
+	// 4. Handle presigned request expiration
+	if authInfo.IsPresigned {
+		if errCode = checkPresignedRequestExpiry(r, authInfo.Date); errCode != s3err.ErrNone {
+			return nil, nil, "", nil, errCode
 		}
 	}
-	// Parse date header.
-	t, e := time.Parse(iso8601Format, dateStr)
-	if e != nil {
-		return nil, s3err.ErrMalformedDate
+
+	// 5. Extract headers that were part of the signature
+	extractedSignedHeaders, errCode := extractSignedHeaders(authInfo.SignedHeaders, r)
+	if errCode != s3err.ErrNone {
+		return nil, nil, "", nil, errCode
 	}
 
-	// Query string.
-	queryStr := req.URL.Query().Encode()
+	// 6. Get the query string for the canonical request
+	queryStr := getCanonicalQueryString(r, authInfo.IsPresigned)
+
+	// 7. Define a closure for the core verification logic to avoid repetition
+	verify := func(urlPath string) (string, s3err.ErrorCode) {
+		return calculateAndVerifySignature(
+			cred.SecretKey,
+			r.Method,
+			urlPath,
+			queryStr,
+			extractedSignedHeaders,
+			authInfo,
+		)
+	}
 
-	// Check if reverse proxy is forwarding with prefix
+	// 8. Verify the signature, trying with X-Forwarded-Prefix first
 	if forwardedPrefix := r.Header.Get("X-Forwarded-Prefix"); forwardedPrefix != "" {
-		// Try signature verification with the forwarded prefix first.
-		// This handles cases where reverse proxies strip URL prefixes and add the X-Forwarded-Prefix header.
-		cleanedPath := buildPathWithForwardedPrefix(forwardedPrefix, req.URL.Path)
-		errCode = iam.verifySignatureWithPath(extractedSignedHeaders, hashedPayload, queryStr, cleanedPath, req.Method, foundCred.SecretKey, t, signV4Values)
+		cleanedPath := buildPathWithForwardedPrefix(forwardedPrefix, r.URL.Path)
+		calculatedSignature, errCode = verify(cleanedPath)
 		if errCode == s3err.ErrNone {
-			return identity, errCode
+			return identity, cred, calculatedSignature, authInfo, s3err.ErrNone
 		}
 	}
 
-	// Try normal signature verification (without prefix)
-	errCode = iam.verifySignatureWithPath(extractedSignedHeaders, hashedPayload, queryStr, req.URL.Path, req.Method, foundCred.SecretKey, t, signV4Values)
-	if errCode == s3err.ErrNone {
-		return identity, errCode
+	// 9. Verify with the original path
+	calculatedSignature, errCode = verify(r.URL.Path)
+	if errCode != s3err.ErrNone {
+		return nil, nil, "", nil, errCode
 	}
 
-	return nil, errCode
+	return identity, cred, calculatedSignature, authInfo, s3err.ErrNone
 }
 
-// buildPathWithForwardedPrefix combines forwarded prefix with URL path while preserving trailing slashes.
-// This ensures compatibility with S3 SDK signatures that include trailing slashes for directory operations.
-func buildPathWithForwardedPrefix(forwardedPrefix, urlPath string) string {
-	fullPath := forwardedPrefix + urlPath
-	hasTrailingSlash := strings.HasSuffix(urlPath, "/") && urlPath != "/"
-	cleanedPath := path.Clean(fullPath)
-	if hasTrailingSlash && !strings.HasSuffix(cleanedPath, "/") {
-		cleanedPath += "/"
-	}
-	return cleanedPath
-}
-
-// verifySignatureWithPath verifies signature with a given path (used for both normal and prefixed paths).
-func (iam *IdentityAccessManagement) verifySignatureWithPath(extractedSignedHeaders http.Header, hashedPayload, queryStr, urlPath, method, secretKey string, t time.Time, signV4Values signValues) s3err.ErrorCode {
-	// Get canonical request.
-	canonicalRequest := getCanonicalRequest(extractedSignedHeaders, hashedPayload, queryStr, urlPath, method)
-
-	// Get string to sign from canonical request.
-	stringToSign := getStringToSign(canonicalRequest, t, signV4Values.Credential.getScope())
-
-	// Get hmac signing key.
-	signingKey := getSigningKey(secretKey, signV4Values.Credential.scope.date.Format(yyyymmdd), signV4Values.Credential.scope.region, signV4Values.Credential.scope.service)
-
-	// Calculate signature.
+// calculateAndVerifySignature contains the core logic for creating the canonical request,
+// string-to-sign, and comparing the final signature.
+func calculateAndVerifySignature(secretKey, method, urlPath, queryStr string, extractedSignedHeaders http.Header, authInfo *v4AuthInfo) (string, s3err.ErrorCode) {
+	canonicalRequest := getCanonicalRequest(extractedSignedHeaders, authInfo.HashedPayload, queryStr, urlPath, method)
+	stringToSign := getStringToSign(canonicalRequest, authInfo.Date, authInfo.Scope)
+	signingKey := getSigningKey(secretKey, authInfo.Date.Format(yyyymmdd), authInfo.Region, authInfo.Service)
 	newSignature := getSignature(signingKey, stringToSign)
 
-	// Verify if signature match.
-	if !compareSignatureV4(newSignature, signV4Values.Signature) {
-		return s3err.ErrSignatureDoesNotMatch
+	if !compareSignatureV4(newSignature, authInfo.Signature) {
+		glog.V(4).Infof("Signature mismatch. Details:\n- CanonicalRequest: %q\n- StringToSign: %q\n- Calculated: %s, Provided: %s",
+			canonicalRequest, stringToSign, newSignature, authInfo.Signature)
+		return "", s3err.ErrSignatureDoesNotMatch
 	}
 
-	return s3err.ErrNone
+	return newSignature, s3err.ErrNone
 }
 
-// verifyPresignedSignatureWithPath verifies presigned signature with a given path (used for both normal and prefixed paths).
-func (iam *IdentityAccessManagement) verifyPresignedSignatureWithPath(extractedSignedHeaders http.Header, hashedPayload, queryStr, urlPath, method, secretKey string, t time.Time, credHeader credentialHeader, signature string) s3err.ErrorCode {
-	// Get canonical request.
-	canonicalRequest := getCanonicalRequest(extractedSignedHeaders, hashedPayload, queryStr, urlPath, method)
+func extractV4AuthInfo(r *http.Request) (*v4AuthInfo, s3err.ErrorCode) {
+	if isRequestPresignedSignatureV4(r) {
+		return extractV4AuthInfoFromQuery(r)
+	}
+	return extractV4AuthInfoFromHeader(r)
+}
 
-	// Get string to sign from canonical request.
-	stringToSign := getStringToSign(canonicalRequest, t, credHeader.getScope())
+func extractV4AuthInfoFromHeader(r *http.Request) (*v4AuthInfo, s3err.ErrorCode) {
+	authHeader := r.Header.Get("Authorization")
+	signV4Values, errCode := parseSignV4(authHeader)
+	if errCode != s3err.ErrNone {
+		return nil, errCode
+	}
 
-	// Get hmac signing key.
-	signingKey := getSigningKey(secretKey, credHeader.scope.date.Format(yyyymmdd), credHeader.scope.region, credHeader.scope.service)
+	var t time.Time
+	if xamz := r.Header.Get("x-amz-date"); xamz != "" {
+		parsed, err := time.Parse(iso8601Format, xamz)
+		if err != nil {
+			return nil, s3err.ErrMalformedDate
+		}
+		t = parsed
+	} else {
+		ds := r.Header.Get("Date")
+		if ds == "" {
+			return nil, s3err.ErrMissingDateHeader
+		}
+		parsed, err := http.ParseTime(ds)
+		if err != nil {
+			return nil, s3err.ErrMalformedDate
+		}
+		t = parsed.UTC()
+	}
 
-	// Calculate expected signature.
-	expectedSignature := getSignature(signingKey, stringToSign)
+	// Validate clock skew: requests cannot be older than 15 minutes from server time to prevent replay attacks
+	const maxSkew = 15 * time.Minute
+	now := time.Now().UTC()
+	if now.Sub(t) > maxSkew || t.Sub(now) > maxSkew {
+		return nil, s3err.ErrRequestTimeTooSkewed
+	}
 
-	// Verify if signature match.
-	if !compareSignatureV4(expectedSignature, signature) {
-		return s3err.ErrSignatureDoesNotMatch
+	hashedPayload := getContentSha256Cksum(r)
+	if signV4Values.Credential.scope.service != "s3" && hashedPayload == emptySHA256 && r.Body != nil {
+		var hashErr error
+		hashedPayload, hashErr = streamHashRequestBody(r, iamRequestBodyLimit)
+		if hashErr != nil {
+			return nil, s3err.ErrInternalError
+		}
 	}
 
-	return s3err.ErrNone
+	return &v4AuthInfo{
+		Signature:     signV4Values.Signature,
+		AccessKey:     signV4Values.Credential.accessKey,
+		SignedHeaders: signV4Values.SignedHeaders,
+		Date:          t,
+		Region:        signV4Values.Credential.scope.region,
+		Service:       signV4Values.Credential.scope.service,
+		Scope:         signV4Values.Credential.getScope(),
+		HashedPayload: hashedPayload,
+		IsPresigned:   false,
+	}, s3err.ErrNone
 }
 
-// Simple implementation for presigned signature verification
-func (iam *IdentityAccessManagement) doesPresignedSignatureMatch(hashedPayload string, r *http.Request) (*Identity, s3err.ErrorCode) {
-	// Parse presigned signature values from query parameters
+func extractV4AuthInfoFromQuery(r *http.Request) (*v4AuthInfo, s3err.ErrorCode) {
 	query := r.URL.Query()
 
-	// Check required parameters
-	algorithm := query.Get("X-Amz-Algorithm")
-	if algorithm != signV4Algorithm {
+	// Validate all required query parameters upfront for fail-fast behavior
+	if query.Get("X-Amz-Algorithm") != signV4Algorithm {
 		return nil, s3err.ErrSignatureVersionNotSupported
 	}
-
-	credential := query.Get("X-Amz-Credential")
-	if credential == "" {
-		return nil, s3err.ErrMissingFields
+	if query.Get("X-Amz-Date") == "" {
+		return nil, s3err.ErrMissingDateHeader
 	}
-
-	signature := query.Get("X-Amz-Signature")
-	if signature == "" {
+	if query.Get("X-Amz-Credential") == "" {
 		return nil, s3err.ErrMissingFields
 	}
-
-	signedHeadersStr := query.Get("X-Amz-SignedHeaders")
-	if signedHeadersStr == "" {
+	if query.Get("X-Amz-Signature") == "" {
 		return nil, s3err.ErrMissingFields
 	}
-
-	dateStr := query.Get("X-Amz-Date")
-	if dateStr == "" {
-		return nil, s3err.ErrMissingDateHeader
-	}
-
-	// Parse credential
-	credHeader, err := parseCredentialHeader("Credential=" + credential)
-	if err != s3err.ErrNone {
-		return nil, err
+	if query.Get("X-Amz-SignedHeaders") == "" {
+		return nil, s3err.ErrMissingFields
 	}
-
-	// Look up identity by access key
-	identity, foundCred, found := iam.lookupByAccessKey(credHeader.accessKey)
-	if !found {
-		return nil, s3err.ErrInvalidAccessKeyID
+	if query.Get("X-Amz-Expires") == "" {
+		return nil, s3err.ErrInvalidQueryParams
 	}
 
 	// Parse date
-	t, e := time.Parse(iso8601Format, dateStr)
-	if e != nil {
+	dateStr := query.Get("X-Amz-Date")
+	t, err := time.Parse(iso8601Format, dateStr)
+	if err != nil {
 		return nil, s3err.ErrMalformedDate
 	}
 
-	// Check expiration
-	expiresStr := query.Get("X-Amz-Expires")
-	if expiresStr != "" {
-		expires, parseErr := strconv.ParseInt(expiresStr, 10, 64)
-		if parseErr != nil {
-			return nil, s3err.ErrMalformedDate
-		}
-		// Check if current time is after the expiration time
-		expirationTime := t.Add(time.Duration(expires) * time.Second)
-		if time.Now().UTC().After(expirationTime) {
-			return nil, s3err.ErrExpiredPresignRequest
-		}
+	// Parse credential header
+	credHeader, errCode := parseCredentialHeader("Credential=" + query.Get("X-Amz-Credential"))
+	if errCode != s3err.ErrNone {
+		return nil, errCode
 	}
 
-	// Parse signed headers
-	signedHeaders := strings.Split(signedHeadersStr, ";")
+	// For presigned URLs, X-Amz-Content-Sha256 must come from the query parameter
+	// (or default to UNSIGNED-PAYLOAD) because that's what was used for signing.
+	// We must NOT check the request header as it wasn't part of the signature calculation.
+	hashedPayload := query.Get("X-Amz-Content-Sha256")
+	if hashedPayload == "" {
+		hashedPayload = unsignedPayload
+	}
+
+	return &v4AuthInfo{
+		Signature:     query.Get("X-Amz-Signature"),
+		AccessKey:     credHeader.accessKey,
+		SignedHeaders: strings.Split(query.Get("X-Amz-SignedHeaders"), ";"),
+		Date:          t,
+		Region:        credHeader.scope.region,
+		Service:       credHeader.scope.service,
+		Scope:         credHeader.getScope(),
+		HashedPayload: hashedPayload,
+		IsPresigned:   true,
+	}, s3err.ErrNone
+}
 
-	// Extract signed headers from request
-	extractedSignedHeaders := make(http.Header)
-	for _, header := range signedHeaders {
-		if header == "host" {
-			extractedSignedHeaders[header] = []string{extractHostHeader(r)}
-			continue
-		}
-		if values := r.Header[http.CanonicalHeaderKey(header)]; len(values) > 0 {
-			extractedSignedHeaders[http.CanonicalHeaderKey(header)] = values
-		}
+func getCanonicalQueryString(r *http.Request, isPresigned bool) string {
+	var queryToEncode string
+	if !isPresigned {
+		queryToEncode = r.URL.Query().Encode()
+	} else {
+		queryForCanonical := r.URL.Query()
+		queryForCanonical.Del("X-Amz-Signature")
+		queryToEncode = queryForCanonical.Encode()
 	}
+	return queryToEncode
+}
 
-	// Remove signature from query for canonical request calculation
-	queryForCanonical := r.URL.Query()
-	queryForCanonical.Del("X-Amz-Signature")
-	queryStr := strings.Replace(queryForCanonical.Encode(), "+", "%20", -1)
+func checkPresignedRequestExpiry(r *http.Request, t time.Time) s3err.ErrorCode {
+	expiresStr := r.URL.Query().Get("X-Amz-Expires")
+	// X-Amz-Expires is validated as required in extractV4AuthInfoFromQuery,
+	// so it should never be empty here
+	expires, err := strconv.ParseInt(expiresStr, 10, 64)
+	if err != nil {
+		return s3err.ErrMalformedDate
+	}
 
-	var errCode s3err.ErrorCode
-	// Check if reverse proxy is forwarding with prefix for presigned URLs
-	if forwardedPrefix := r.Header.Get("X-Forwarded-Prefix"); forwardedPrefix != "" {
-		// Try signature verification with the forwarded prefix first.
-		// This handles cases where reverse proxies strip URL prefixes and add the X-Forwarded-Prefix header.
-		cleanedPath := buildPathWithForwardedPrefix(forwardedPrefix, r.URL.Path)
-		errCode = iam.verifyPresignedSignatureWithPath(extractedSignedHeaders, hashedPayload, queryStr, cleanedPath, r.Method, foundCred.SecretKey, t, credHeader, signature)
-		if errCode == s3err.ErrNone {
-			return identity, errCode
-		}
+	// The maximum value for X-Amz-Expires is 604800 seconds (7 days)
+	// Allow 0 but it will immediately fail expiration check
+	if expires < 0 {
+		return s3err.ErrNegativeExpires
+	}
+	if expires > 604800 {
+		return s3err.ErrMaximumExpires
 	}
 
-	// Try normal signature verification (without prefix)
-	errCode = iam.verifyPresignedSignatureWithPath(extractedSignedHeaders, hashedPayload, queryStr, r.URL.Path, r.Method, foundCred.SecretKey, t, credHeader, signature)
-	if errCode == s3err.ErrNone {
-		return identity, errCode
+	expirationTime := t.Add(time.Duration(expires) * time.Second)
+	if time.Now().UTC().After(expirationTime) {
+		return s3err.ErrExpiredPresignRequest
 	}
+	return s3err.ErrNone
+}
+
+func (iam *IdentityAccessManagement) doesSignatureMatch(r *http.Request) (*Identity, string, s3err.ErrorCode) {
+	identity, _, calculatedSignature, _, errCode := iam.verifyV4Signature(r, false)
+	return identity, calculatedSignature, errCode
+}
 
-	return nil, errCode
+func (iam *IdentityAccessManagement) doesPresignedSignatureMatch(r *http.Request) (*Identity, string, s3err.ErrorCode) {
+	identity, _, calculatedSignature, _, errCode := iam.verifyV4Signature(r, false)
+	return identity, calculatedSignature, errCode
 }
 
 // credentialHeader data type represents structured form of Credential
@@ -531,7 +595,7 @@ func extractHostHeader(r *http.Request) string {
 		// Check if reverse proxy also forwarded the port
 		if forwardedPort := r.Header.Get("X-Forwarded-Port"); forwardedPort != "" {
 			// Determine the protocol to check for standard ports
-			proto := r.Header.Get("X-Forwarded-Proto")
+			proto := strings.ToLower(r.Header.Get("X-Forwarded-Proto"))
 			// Only add port if it's not the standard port for the protocol
 			if (proto == "https" && forwardedPort != "443") || (proto != "https" && forwardedPort != "80") {
 				return forwardedHost + ":" + forwardedPort
diff --git a/weed/s3api/auth_signature_v4_test.go b/weed/s3api/auth_signature_v4_test.go
new file mode 100644
index 000000000..312e88767
--- /dev/null
+++ b/weed/s3api/auth_signature_v4_test.go
@@ -0,0 +1,91 @@
+package s3api
+
+import (
+	"testing"
+)
+
+func TestBuildPathWithForwardedPrefix(t *testing.T) {
+	tests := []struct {
+		name            string
+		forwardedPrefix string
+		urlPath         string
+		expected        string
+	}{
+		{
+			name:            "empty prefix returns urlPath",
+			forwardedPrefix: "",
+			urlPath:         "/bucket/obj",
+			expected:        "/bucket/obj",
+		},
+		{
+			name:            "prefix without trailing slash",
+			forwardedPrefix: "/storage",
+			urlPath:         "/bucket/obj",
+			expected:        "/storage/bucket/obj",
+		},
+		{
+			name:            "prefix with trailing slash",
+			forwardedPrefix: "/storage/",
+			urlPath:         "/bucket/obj",
+			expected:        "/storage/bucket/obj",
+		},
+		{
+			name:            "prefix without leading slash",
+			forwardedPrefix: "storage",
+			urlPath:         "/bucket/obj",
+			expected:        "/storage/bucket/obj",
+		},
+		{
+			name:            "prefix without leading slash and with trailing slash",
+			forwardedPrefix: "storage/",
+			urlPath:         "/bucket/obj",
+			expected:        "/storage/bucket/obj",
+		},
+		{
+			name:            "preserve double slashes in key",
+			forwardedPrefix: "/storage",
+			urlPath:         "/bucket//obj",
+			expected:        "/storage/bucket//obj",
+		},
+		{
+			name:            "preserve trailing slash in urlPath",
+			forwardedPrefix: "/storage",
+			urlPath:         "/bucket/folder/",
+			expected:        "/storage/bucket/folder/",
+		},
+		{
+			name:            "preserve trailing slash with prefix having trailing slash",
+			forwardedPrefix: "/storage/",
+			urlPath:         "/bucket/folder/",
+			expected:        "/storage/bucket/folder/",
+		},
+		{
+			name:            "root path",
+			forwardedPrefix: "/storage",
+			urlPath:         "/",
+			expected:        "/storage/",
+		},
+		{
+			name:            "complex key with multiple slashes",
+			forwardedPrefix: "/api/v1",
+			urlPath:         "/bucket/path//with///slashes",
+			expected:        "/api/v1/bucket/path//with///slashes",
+		},
+		{
+			name:            "urlPath without leading slash",
+			forwardedPrefix: "/storage",
+			urlPath:         "bucket/obj",
+			expected:        "/storage/bucket/obj",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := buildPathWithForwardedPrefix(tt.forwardedPrefix, tt.urlPath)
+			if result != tt.expected {
+				t.Errorf("buildPathWithForwardedPrefix(%q, %q) = %q, want %q",
+					tt.forwardedPrefix, tt.urlPath, result, tt.expected)
+			}
+		})
+	}
+}
diff --git a/weed/s3api/auto_signature_v4_test.go b/weed/s3api/auto_signature_v4_test.go
index bf11a0906..71cae3546 100644
--- a/weed/s3api/auto_signature_v4_test.go
+++ b/weed/s3api/auto_signature_v4_test.go
@@ -229,8 +229,12 @@ func preSignV4(iam *IdentityAccessManagement, req *http.Request, accessKey, secr
 	// Set the query on the URL (without signature yet)
 	req.URL.RawQuery = query.Encode()
 
-	// Get the payload hash
-	hashedPayload := getContentSha256Cksum(req)
+	// For presigned URLs, the payload hash must be UNSIGNED-PAYLOAD (or from query param if explicitly set)
+	// We should NOT use request headers as they're not part of the presigned URL
+	hashedPayload := query.Get("X-Amz-Content-Sha256")
+	if hashedPayload == "" {
+		hashedPayload = unsignedPayload
+	}
 
 	// Extract signed headers
 	extractedSignedHeaders := make(http.Header)
@@ -314,7 +318,7 @@ func TestSignatureV4WithForwardedPrefix(t *testing.T) {
 			signV4WithPath(r, "AKIAIOSFODNN7EXAMPLE", "wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY", tt.expectedPath)
 
 			// Test signature verification
-			_, errCode := iam.doesSignatureMatch(getContentSha256Cksum(r), r)
+			_, _, errCode := iam.doesSignatureMatch(r)
 			if errCode != s3err.ErrNone {
 				t.Errorf("Expected successful signature validation with X-Forwarded-Prefix %q, got error: %v (code: %d)", tt.forwardedPrefix, errCode, int(errCode))
 			}
@@ -380,7 +384,7 @@ func TestSignatureV4WithForwardedPrefixTrailingSlash(t *testing.T) {
 			signV4WithPath(r, "AKIAIOSFODNN7EXAMPLE", "wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY", tt.expectedPath)
 
 			// Test signature verification - this should succeed even with trailing slashes
-			_, errCode := iam.doesSignatureMatch(getContentSha256Cksum(r), r)
+			_, _, errCode := iam.doesSignatureMatch(r)
 			if errCode != s3err.ErrNone {
 				t.Errorf("Expected successful signature validation with trailing slash in path %q, got error: %v (code: %d)", tt.urlPath, errCode, int(errCode))
 			}
@@ -475,7 +479,7 @@ func TestSignatureV4WithForwardedPort(t *testing.T) {
 			signV4WithPath(r, "AKIAIOSFODNN7EXAMPLE", "wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY", r.URL.Path)
 
 			// Test signature verification
-			_, errCode := iam.doesSignatureMatch(getContentSha256Cksum(r), r)
+			_, _, errCode := iam.doesSignatureMatch(r)
 			if errCode != s3err.ErrNone {
 				t.Errorf("Expected successful signature validation with forwarded port, got error: %v (code: %d)", errCode, int(errCode))
 			}
@@ -508,12 +512,50 @@ func TestPresignedSignatureV4Basic(t *testing.T) {
 	}
 
 	// Test presigned signature verification
-	_, errCode := iam.doesPresignedSignatureMatch(getContentSha256Cksum(r), r)
+	_, _, errCode := iam.doesPresignedSignatureMatch(r)
 	if errCode != s3err.ErrNone {
 		t.Errorf("Expected successful presigned signature validation, got error: %v (code: %d)", errCode, int(errCode))
 	}
 }
 
+// TestPresignedSignatureV4MissingExpires verifies that X-Amz-Expires is required for presigned URLs
+func TestPresignedSignatureV4MissingExpires(t *testing.T) {
+	iam := newTestIAM()
+
+	// Create a presigned request
+	r, err := newTestRequest("GET", "https://example.com/test-bucket/test-object", 0, nil)
+	if err != nil {
+		t.Fatalf("Failed to create test request: %v", err)
+	}
+
+	r = mux.SetURLVars(r, map[string]string{
+		"bucket": "test-bucket",
+		"object": "test-object",
+	})
+	r.Header.Set("Host", "example.com")
+
+	// Manually construct presigned URL query parameters WITHOUT X-Amz-Expires
+	now := time.Now().UTC()
+	dateStr := now.Format(iso8601Format)
+	scope := fmt.Sprintf("%s/%s/%s/%s", now.Format(yyyymmdd), "us-east-1", "s3", "aws4_request")
+	credential := fmt.Sprintf("%s/%s", "AKIAIOSFODNN7EXAMPLE", scope)
+
+	query := r.URL.Query()
+	query.Set("X-Amz-Algorithm", signV4Algorithm)
+	query.Set("X-Amz-Credential", credential)
+	query.Set("X-Amz-Date", dateStr)
+	// Intentionally NOT setting X-Amz-Expires
+	query.Set("X-Amz-SignedHeaders", "host")
+	query.Set("X-Amz-Signature", "dummy-signature") // Signature doesn't matter, should fail earlier
+	r.URL.RawQuery = query.Encode()
+
+	// Test presigned signature verification - should fail with ErrInvalidQueryParams
+	_, _, errCode := iam.doesPresignedSignatureMatch(r)
+	if errCode != s3err.ErrInvalidQueryParams {
+		t.Errorf("Expected ErrInvalidQueryParams for missing X-Amz-Expires, got: %v (code: %d)", errCode, int(errCode))
+	}
+}
+
 // Test X-Forwarded-Prefix support for presigned URLs
 func TestPresignedSignatureV4WithForwardedPrefix(t *testing.T) {
 	tests := []struct {
@@ -573,7 +615,8 @@ func TestPresignedSignatureV4WithForwardedPrefix(t *testing.T) {
 			r.Header.Set("X-Forwarded-Host", "example.com")
 
 			// Test presigned signature verification
-			_, errCode := iam.doesPresignedSignatureMatch(getContentSha256Cksum(r), r)
+			_, _, errCode := iam.doesPresignedSignatureMatch(r)
+
 			if errCode != s3err.ErrNone {
 				t.Errorf("Expected successful presigned signature validation with X-Forwarded-Prefix %q, got error: %v (code: %d)", tt.forwardedPrefix, errCode, int(errCode))
 			}
@@ -640,7 +683,8 @@ func TestPresignedSignatureV4WithForwardedPrefixTrailingSlash(t *testing.T) {
 			r.Header.Set("X-Forwarded-Host", "example.com")
 
 			// Test presigned signature verification - this should succeed with trailing slashes
-			_, errCode := iam.doesPresignedSignatureMatch(getContentSha256Cksum(r), r)
+			_, _, errCode := iam.doesPresignedSignatureMatch(r)
+
 			if errCode != s3err.ErrNone {
 				t.Errorf("Expected successful presigned signature validation with trailing slash in path %q, got error: %v (code: %d)", tt.strippedPath, errCode, int(errCode))
 			}
@@ -669,8 +713,12 @@ func preSignV4WithPath(iam *IdentityAccessManagement, req *http.Request, accessK
 	// Set the query on the URL (without signature yet)
 	req.URL.RawQuery = query.Encode()
 
-	// Get the payload hash
-	hashedPayload := getContentSha256Cksum(req)
+	// For presigned URLs, the payload hash must be UNSIGNED-PAYLOAD (or from query param if explicitly set)
+	// We should NOT use request headers as they're not part of the presigned URL
+	hashedPayload := query.Get("X-Amz-Content-Sha256")
+	if hashedPayload == "" {
+		hashedPayload = unsignedPayload
+	}
 
 	// Extract signed headers
 	extractedSignedHeaders := make(http.Header)
@@ -884,7 +932,7 @@ func signRequestV4(req *http.Request, accessKey, secretKey string) error {
 		return fmt.Errorf("Invalid hashed payload")
 	}
 
-	currTime := time.Now()
+	currTime := time.Now().UTC()
 
 	// Set x-amz-date.
 	req.Header.Set("x-amz-date", currTime.Format(iso8601Format))
@@ -1061,10 +1109,6 @@ func TestIAMPayloadHashComputation(t *testing.T) {
 	req.Header.Set("Content-Type", "application/x-www-form-urlencoded; charset=utf-8")
 	req.Header.Set("Host", "localhost:8111")
 
-	// Compute expected payload hash
-	expectedHash := sha256.Sum256([]byte(testPayload))
-	expectedHashStr := hex.EncodeToString(expectedHash[:])
-
 	// Create an IAM-style authorization header with "iam" service instead of "s3"
 	now := time.Now().UTC()
 	dateStr := now.Format("20060102T150405Z")
@@ -1079,7 +1123,7 @@ func TestIAMPayloadHashComputation(t *testing.T) {
 
 	// Test the doesSignatureMatch function directly
 	// This should now compute the correct payload hash for IAM requests
-	identity, errCode := iam.doesSignatureMatch(expectedHashStr, req)
+	identity, _, errCode := iam.doesSignatureMatch(req)
 
 	// Even though the signature will fail (dummy signature),
 	// the fact that we get past the credential parsing means the payload hash was computed correctly
@@ -1141,7 +1185,7 @@ func TestS3PayloadHashNoRegression(t *testing.T) {
 	req.Header.Set("Authorization", authHeader)
 
 	// This should use the emptySHA256 hash and not try to read the body
-	identity, errCode := iam.doesSignatureMatch(emptySHA256, req)
+	identity, _, errCode := iam.doesSignatureMatch(req)
 
 	// Should get signature mismatch (because of dummy signature) but not other errors
 	assert.Equal(t, s3err.ErrSignatureDoesNotMatch, errCode)
@@ -1192,7 +1236,7 @@ func TestIAMEmptyBodyPayloadHash(t *testing.T) {
 	req.Header.Set("Authorization", authHeader)
 
 	// Even with an IAM request, empty body should result in emptySHA256
-	identity, errCode := iam.doesSignatureMatch(emptySHA256, req)
+	identity, _, errCode := iam.doesSignatureMatch(req)
 
 	// Should get signature mismatch (because of dummy signature) but not other errors
 	assert.Equal(t, s3err.ErrSignatureDoesNotMatch, errCode)
@@ -1235,10 +1279,6 @@ func TestSTSPayloadHashComputation(t *testing.T) {
 	req.Header.Set("Content-Type", "application/x-www-form-urlencoded; charset=utf-8")
 	req.Header.Set("Host", "localhost:8112")
 
-	// Compute expected payload hash
-	expectedHash := sha256.Sum256([]byte(testPayload))
-	expectedHashStr := hex.EncodeToString(expectedHash[:])
-
 	// Create an STS-style authorization header with "sts" service
 	now := time.Now().UTC()
 	dateStr := now.Format("20060102T150405Z")
@@ -1252,7 +1292,7 @@ func TestSTSPayloadHashComputation(t *testing.T) {
 
 	// Test the doesSignatureMatch function
 	// This should compute the correct payload hash for STS requests (non-S3 service)
-	identity, errCode := iam.doesSignatureMatch(expectedHashStr, req)
+	identity, _, errCode := iam.doesSignatureMatch(req)
 
 	// Should get signature mismatch (dummy signature) but payload hash should be computed correctly
 	assert.Equal(t, s3err.ErrSignatureDoesNotMatch, errCode)
@@ -1317,7 +1357,7 @@ func TestGitHubIssue7080Scenario(t *testing.T) {
 
 	// Since we're using a dummy signature, we expect signature mismatch, but the important
 	// thing is that it doesn't fail earlier due to payload hash computation issues
-	identity, errCode := iam.doesSignatureMatch(emptySHA256, req)
+	identity, _, errCode := iam.doesSignatureMatch(req)
 
 	// The error should be signature mismatch, not payload related
 	assert.Equal(t, s3err.ErrSignatureDoesNotMatch, errCode)
@@ -1357,32 +1397,37 @@ func TestIAMSignatureServiceMatching(t *testing.T) {
 	// Use the exact payload and headers from the failing logs
 	testPayload := "Action=CreateAccessKey&UserName=admin&Version=2010-05-08"
 
+	// Use current time to avoid clock skew validation failures
+	now := time.Now().UTC()
+	amzDate := now.Format(iso8601Format)
+	dateStamp := now.Format(yyyymmdd)
+
 	// Create request exactly as shown in logs
 	req, err := http.NewRequest("POST", "http://localhost:8111/", strings.NewReader(testPayload))
 	assert.NoError(t, err)
 
 	req.Header.Set("Content-Type", "application/x-www-form-urlencoded; charset=utf-8")
 	req.Header.Set("Host", "localhost:8111")
-	req.Header.Set("X-Amz-Date", "20250805T082934Z")
+	req.Header.Set("X-Amz-Date", amzDate)
 
 	// Calculate the expected signature using the correct IAM service
 	// This simulates what botocore/AWS SDK would calculate
-	credentialScope := "20250805/us-east-1/iam/aws4_request"
+	credentialScope := dateStamp + "/us-east-1/iam/aws4_request"
 
 	// Calculate the actual payload hash for our test payload
 	actualPayloadHash := getSHA256Hash([]byte(testPayload))
 
 	// Build the canonical request with the actual payload hash
-	canonicalRequest := "POST\n/\n\ncontent-type:application/x-www-form-urlencoded; charset=utf-8\nhost:localhost:8111\nx-amz-date:20250805T082934Z\n\ncontent-type;host;x-amz-date\n" + actualPayloadHash
+	canonicalRequest := "POST\n/\n\ncontent-type:application/x-www-form-urlencoded; charset=utf-8\nhost:localhost:8111\nx-amz-date:" + amzDate + "\n\ncontent-type;host;x-amz-date\n" + actualPayloadHash
 
 	// Calculate the canonical request hash
 	canonicalRequestHash := getSHA256Hash([]byte(canonicalRequest))
 
 	// Build the string to sign
-	stringToSign := "AWS4-HMAC-SHA256\n20250805T082934Z\n" + credentialScope + "\n" + canonicalRequestHash
+	stringToSign := "AWS4-HMAC-SHA256\n" + amzDate + "\n" + credentialScope + "\n" + canonicalRequestHash
 
 	// Calculate expected signature using IAM service (what client sends)
-	expectedSigningKey := getSigningKey("power_user_secret", "20250805", "us-east-1", "iam")
+	expectedSigningKey := getSigningKey("power_user_secret", dateStamp, "us-east-1", "iam")
 	expectedSignature := getSignature(expectedSigningKey, stringToSign)
 
 	// Create authorization header with the correct signature
@@ -1391,7 +1436,8 @@ func TestIAMSignatureServiceMatching(t *testing.T) {
 	req.Header.Set("Authorization", authHeader)
 
 	// Now test that SeaweedFS computes the same signature with our fix
-	identity, errCode := iam.doesSignatureMatch(actualPayloadHash, req)
+	identity, computedSignature, errCode := iam.doesSignatureMatch(req)
+	assert.Equal(t, expectedSignature, computedSignature)
 
 	// With the fix, the signatures should match and we should get a successful authentication
 	assert.Equal(t, s3err.ErrNone, errCode)
@@ -1481,7 +1527,7 @@ func TestIAMLargeBodySecurityLimit(t *testing.T) {
 	req.Header.Set("Authorization", authHeader)
 
 	// The function should complete successfully but limit the body to 10 MiB
-	identity, errCode := iam.doesSignatureMatch(emptySHA256, req)
+	identity, _, errCode := iam.doesSignatureMatch(req)
 
 	// Should get signature mismatch (dummy signature) but not internal error
 	assert.Equal(t, s3err.ErrSignatureDoesNotMatch, errCode)
diff --git a/weed/s3api/chunked_reader_v4.go b/weed/s3api/chunked_reader_v4.go
index ca35fe3cd..39d8336f0 100644
--- a/weed/s3api/chunked_reader_v4.go
+++ b/weed/s3api/chunked_reader_v4.go
@@ -34,7 +34,6 @@ import (
 	"time"
 
 	"github.com/seaweedfs/seaweedfs/weed/glog"
-	"github.com/seaweedfs/seaweedfs/weed/s3api/s3_constants"
 	"github.com/seaweedfs/seaweedfs/weed/s3api/s3err"
 
 	"github.com/dustin/go-humanize"
@@ -47,23 +46,13 @@ import (
 // returns signature, error otherwise if the signature mismatches or any other
 // error while parsing and validating.
 func (iam *IdentityAccessManagement) calculateSeedSignature(r *http.Request) (cred *Credential, signature string, region string, service string, date time.Time, errCode s3err.ErrorCode) {
-
-	// Copy request.
-	req := *r
-
-	// Save authorization header.
-	v4Auth := req.Header.Get("Authorization")
-
-	// Parse signature version '4' header.
-	signV4Values, errCode := parseSignV4(v4Auth)
+	_, credential, calculatedSignature, authInfo, errCode := iam.verifyV4Signature(r, true)
 	if errCode != s3err.ErrNone {
 		return nil, "", "", "", time.Time{}, errCode
 	}
 
-	contentSha256Header := req.Header.Get("X-Amz-Content-Sha256")
-
-	switch contentSha256Header {
-	// Payload for STREAMING signature should be 'STREAMING-AWS4-HMAC-SHA256-PAYLOAD'
+	// This check ensures we only proceed for streaming uploads.
+	switch authInfo.HashedPayload {
 	case streamingContentSHA256:
 		glog.V(3).Infof("streaming content sha256")
 	case streamingUnsignedPayload:
@@ -72,64 +61,7 @@ func (iam *IdentityAccessManagement) calculateSeedSignature(r *http.Request) (cr
 		return nil, "", "", "", time.Time{}, s3err.ErrContentSHA256Mismatch
 	}
 
-	// Payload streaming.
-	payload := contentSha256Header
-
-	// Extract all the signed headers along with its values.
-	extractedSignedHeaders, errCode := extractSignedHeaders(signV4Values.SignedHeaders, r)
-	if errCode != s3err.ErrNone {
-		return nil, "", "", "", time.Time{}, errCode
-	}
-	// Verify if the access key id matches.
-	identity, cred, found := iam.lookupByAccessKey(signV4Values.Credential.accessKey)
-	if !found {
-		return nil, "", "", "", time.Time{}, s3err.ErrInvalidAccessKeyID
-	}
-
-	bucket, object := s3_constants.GetBucketAndObject(r)
-	if !identity.canDo(s3_constants.ACTION_WRITE, bucket, object) {
-		errCode = s3err.ErrAccessDenied
-		return
-	}
-
-	// Verify if region is valid.
-	region = signV4Values.Credential.scope.region
-
-	// Extract date, if not present throw error.
-	var dateStr string
-	if dateStr = req.Header.Get(http.CanonicalHeaderKey("x-amz-date")); dateStr == "" {
-		if dateStr = r.Header.Get("Date"); dateStr == "" {
-			return nil, "", "", "", time.Time{}, s3err.ErrMissingDateHeader
-		}
-	}
-
-	// Parse date header.
-	date, err := time.Parse(iso8601Format, dateStr)
-	if err != nil {
-		return nil, "", "", "", time.Time{}, s3err.ErrMalformedDate
-	}
-	// Query string.
-	queryStr := req.URL.Query().Encode()
-
-	// Get canonical request.
-	canonicalRequest := getCanonicalRequest(extractedSignedHeaders, payload, queryStr, req.URL.Path, req.Method)
-
-	// Get string to sign from canonical request.
-	stringToSign := getStringToSign(canonicalRequest, date, signV4Values.Credential.getScope())
-
-	// Get hmac signing key.
-	signingKey := getSigningKey(cred.SecretKey, signV4Values.Credential.scope.date.Format(yyyymmdd), region, signV4Values.Credential.scope.service)
-
-	// Calculate signature.
-	newSignature := getSignature(signingKey, stringToSign)
-
-	// Verify if signature match.
-	if !compareSignatureV4(newSignature, signV4Values.Signature) {
-		return nil, "", "", "", time.Time{}, s3err.ErrSignatureDoesNotMatch
-	}
-
-	// Return calculated signature.
-	return cred, newSignature, region, signV4Values.Credential.scope.service, date, s3err.ErrNone
+	return credential, calculatedSignature, authInfo.Region, authInfo.Service, authInfo.Date, s3err.ErrNone
 }
 
 const maxLineLength = 4 * humanize.KiByte // assumed <= bufio.defaultBufSize 4KiB
@@ -149,7 +81,7 @@ func (iam *IdentityAccessManagement) newChunkedReader(req *http.Request) (io.Rea
 	contentSha256Header := req.Header.Get("X-Amz-Content-Sha256")
 	authorizationHeader := req.Header.Get("Authorization")
 
-	var ident *Credential
+	var credential *Credential
 	var seedSignature, region, service string
 	var seedDate time.Time
 	var errCode s3err.ErrorCode
@@ -158,7 +90,7 @@ func (iam *IdentityAccessManagement) newChunkedReader(req *http.Request) (io.Rea
 	// Payload for STREAMING signature should be 'STREAMING-AWS4-HMAC-SHA256-PAYLOAD'
 	case streamingContentSHA256:
 		glog.V(3).Infof("streaming content sha256")
-		ident, seedSignature, region, service, seedDate, errCode = iam.calculateSeedSignature(req)
+		credential, seedSignature, region, service, seedDate, errCode = iam.calculateSeedSignature(req)
 		if errCode != s3err.ErrNone {
 			return nil, errCode
 		}
@@ -186,7 +118,7 @@ func (iam *IdentityAccessManagement) newChunkedReader(req *http.Request) (io.Rea
 	checkSumWriter := getCheckSumWriter(checksumAlgorithm)
 
 	return &s3ChunkedReader{
-		cred:              ident,
+		cred:              credential,
 		reader:            bufio.NewReader(req.Body),
 		seedSignature:     seedSignature,
 		seedDate:          seedDate,
diff --git a/weed/s3api/chunked_reader_v4_test.go b/weed/s3api/chunked_reader_v4_test.go
index 786df3465..c9bad1d8a 100644
--- a/weed/s3api/chunked_reader_v4_test.go
+++ b/weed/s3api/chunked_reader_v4_test.go
@@ -9,6 +9,7 @@ import (
 	"strings"
 	"sync"
 	"testing"
+	"time"
 
 	"hash/crc32"
 
@@ -16,66 +17,19 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
+// getDefaultTimestamp returns a current timestamp for tests
+func getDefaultTimestamp() string {
+	return time.Now().UTC().Format(iso8601Format)
+}
+
 const (
-	defaultTimestamp       = "20130524T000000Z"
+	defaultTimestamp       = "20130524T000000Z" // Legacy constant for reference
 	defaultBucketName      = "examplebucket"
 	defaultAccessKeyId     = "AKIAIOSFODNN7EXAMPLE"
 	defaultSecretAccessKey = "wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY"
 	defaultRegion          = "us-east-1"
 )
 
-func generatestreamingAws4HmacSha256Payload() string {
-	// This test will implement the following scenario:
-	// https://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-streaming.html#example-signature-calculations-streaming
-
-	chunk1 := "10000;chunk-signature=ad80c730a21e5b8d04586a2213dd63b9a0e99e0e2307b0ade35a65485a288648\r\n" +
-		strings.Repeat("a", 65536) + "\r\n"
-	chunk2 := "400;chunk-signature=0055627c9e194cb4542bae2aa5492e3c1575bbb81b612b7d234b86a503ef5497\r\n" +
-		strings.Repeat("a", 1024) + "\r\n"
-	chunk3 := "0;chunk-signature=b6c6ea8a5354eaf15b3cb7646744f4275b71ea724fed81ceb9323e279d449df9\r\n" +
-		"\r\n" // The last chunk is empty
-
-	payload := chunk1 + chunk2 + chunk3
-	return payload
-}
-
-func NewRequeststreamingAws4HmacSha256Payload() (*http.Request, error) {
-	// This test will implement the following scenario:
-	// https://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-streaming.html#example-signature-calculations-streaming
-
-	payload := generatestreamingAws4HmacSha256Payload()
-	req, err := http.NewRequest("PUT", "http://s3.amazonaws.com/examplebucket/chunkObject.txt", bytes.NewReader([]byte(payload)))
-	if err != nil {
-		return nil, err
-	}
-
-	req.Header.Set("Host", "s3.amazonaws.com")
-	req.Header.Set("x-amz-date", defaultTimestamp)
-	req.Header.Set("x-amz-storage-class", "REDUCED_REDUNDANCY")
-	req.Header.Set("Authorization", "AWS4-HMAC-SHA256 Credential=AKIAIOSFODNN7EXAMPLE/20130524/us-east-1/s3/aws4_request,SignedHeaders=content-encoding;content-length;host;x-amz-content-sha256;x-amz-date;x-amz-decoded-content-length;x-amz-storage-class,Signature=4f232c4386841ef735655705268965c44a0e4690baa4adea153f7db9fa80a0a9")
-	req.Header.Set("x-amz-content-sha256", "STREAMING-AWS4-HMAC-SHA256-PAYLOAD")
-	req.Header.Set("Content-Encoding", "aws-chunked")
-	req.Header.Set("x-amz-decoded-content-length", "66560")
-	req.Header.Set("Content-Length", "66824")
-
-	return req, nil
-}
-
-func TestNewSignV4ChunkedReaderstreamingAws4HmacSha256Payload(t *testing.T) {
-	// This test will implement the following scenario:
-	// https://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-streaming.html#example-signature-calculations-streaming
-	req, err := NewRequeststreamingAws4HmacSha256Payload()
-	if err != nil {
-		t.Fatalf("Failed to create request: %v", err)
-	}
-	iam := setupIam()
-
-	// The expected payload a long string of 'a's
-	expectedPayload := strings.Repeat("a", 66560)
-
-	runWithRequest(iam, req, t, expectedPayload)
-}
-
 func generateStreamingUnsignedPayloadTrailerPayload(includeFinalCRLF bool) string {
 	// This test will implement the following scenario:
 	// https://docs.aws.amazon.com/AmazonS3/latest/userguide/checking-object-integrity.html
@@ -117,7 +71,7 @@ func NewRequestStreamingUnsignedPayloadTrailer(includeFinalCRLF bool) (*http.Req
 	}
 
 	req.Header.Set("Host", "amzn-s3-demo-bucket")
-	req.Header.Set("x-amz-date", defaultTimestamp)
+	req.Header.Set("x-amz-date", getDefaultTimestamp())
 	req.Header.Set("Content-Encoding", "aws-chunked")
 	req.Header.Set("x-amz-decoded-content-length", "17408")
 	req.Header.Set("x-amz-content-sha256", "STREAMING-UNSIGNED-PAYLOAD-TRAILER")
@@ -194,3 +148,169 @@ func setupIam() IdentityAccessManagement {
 	iam.accessKeyIdent[defaultAccessKeyId] = iam.identities[0]
 	return iam
 }
+
+// TestSignedStreamingUpload tests streaming uploads with signed chunks
+// This replaces the removed AWS example test with a dynamic signature generation approach
+func TestSignedStreamingUpload(t *testing.T) {
+	iam := setupIam()
+
+	// Create a simple streaming upload with 2 chunks
+	chunk1Data := strings.Repeat("a", 1024)
+	chunk2Data := strings.Repeat("b", 512)
+
+	// Use current time for signatures
+	now := time.Now().UTC()
+	amzDate := now.Format(iso8601Format)
+	dateStamp := now.Format(yyyymmdd)
+
+	// Calculate seed signature
+	scope := dateStamp + "/" + defaultRegion + "/s3/aws4_request"
+
+	// Build canonical request for seed signature
+	hashedPayload := "STREAMING-AWS4-HMAC-SHA256-PAYLOAD"
+	canonicalHeaders := "content-encoding:aws-chunked\n" +
+		"host:s3.amazonaws.com\n" +
+		"x-amz-content-sha256:" + hashedPayload + "\n" +
+		"x-amz-date:" + amzDate + "\n" +
+		"x-amz-decoded-content-length:1536\n"
+	signedHeaders := "content-encoding;host;x-amz-content-sha256;x-amz-date;x-amz-decoded-content-length"
+
+	canonicalRequest := "PUT\n" +
+		"/test-bucket/test-object\n" +
+		"\n" +
+		canonicalHeaders + "\n" +
+		signedHeaders + "\n" +
+		hashedPayload
+
+	canonicalRequestHash := getSHA256Hash([]byte(canonicalRequest))
+	stringToSign := "AWS4-HMAC-SHA256\n" + amzDate + "\n" + scope + "\n" + canonicalRequestHash
+
+	signingKey := getSigningKey(defaultSecretAccessKey, dateStamp, defaultRegion, "s3")
+	seedSignature := getSignature(signingKey, stringToSign)
+
+	// Calculate chunk signatures
+	chunk1Hash := getSHA256Hash([]byte(chunk1Data))
+	chunk1StringToSign := "AWS4-HMAC-SHA256-PAYLOAD\n" + amzDate + "\n" + scope + "\n" +
+		seedSignature + "\n" + emptySHA256 + "\n" + chunk1Hash
+	chunk1Signature := getSignature(signingKey, chunk1StringToSign)
+
+	chunk2Hash := getSHA256Hash([]byte(chunk2Data))
+	chunk2StringToSign := "AWS4-HMAC-SHA256-PAYLOAD\n" + amzDate + "\n" + scope + "\n" +
+		chunk1Signature + "\n" + emptySHA256 + "\n" + chunk2Hash
+	chunk2Signature := getSignature(signingKey, chunk2StringToSign)
+
+	finalStringToSign := "AWS4-HMAC-SHA256-PAYLOAD\n" + amzDate + "\n" + scope + "\n" +
+		chunk2Signature + "\n" + emptySHA256 + "\n" + emptySHA256
+	finalSignature := getSignature(signingKey, finalStringToSign)
+
+	// Build the chunked payload
+	payload := fmt.Sprintf("400;chunk-signature=%s\r\n%s\r\n", chunk1Signature, chunk1Data) +
+		fmt.Sprintf("200;chunk-signature=%s\r\n%s\r\n", chunk2Signature, chunk2Data) +
+		fmt.Sprintf("0;chunk-signature=%s\r\n\r\n", finalSignature)
+
+	// Create the request
+	req, err := http.NewRequest("PUT", "http://s3.amazonaws.com/test-bucket/test-object",
+		bytes.NewReader([]byte(payload)))
+	assert.NoError(t, err)
+
+	req.Header.Set("Host", "s3.amazonaws.com")
+	req.Header.Set("x-amz-date", amzDate)
+	req.Header.Set("x-amz-content-sha256", hashedPayload)
+	req.Header.Set("Content-Encoding", "aws-chunked")
+	req.Header.Set("x-amz-decoded-content-length", "1536")
+
+	authHeader := fmt.Sprintf("AWS4-HMAC-SHA256 Credential=%s/%s, SignedHeaders=%s, Signature=%s",
+		defaultAccessKeyId, scope, signedHeaders, seedSignature)
+	req.Header.Set("Authorization", authHeader)
+
+	// Test the chunked reader
+	reader, errCode := iam.newChunkedReader(req)
+	assert.Equal(t, s3err.ErrNone, errCode)
+	assert.NotNil(t, reader)
+
+	// Read and verify the payload
+	data, err := io.ReadAll(reader)
+	assert.NoError(t, err)
+	assert.Equal(t, chunk1Data+chunk2Data, string(data))
+}
+
+// TestSignedStreamingUploadInvalidSignature tests that invalid chunk signatures are rejected
+// This is a negative test case to ensure signature validation is actually working
+func TestSignedStreamingUploadInvalidSignature(t *testing.T) {
+	iam := setupIam()
+
+	// Create a simple streaming upload with 1 chunk
+	chunk1Data := strings.Repeat("a", 1024)
+
+	// Use current time for signatures
+	now := time.Now().UTC()
+	amzDate := now.Format(iso8601Format)
+	dateStamp := now.Format(yyyymmdd)
+
+	// Calculate seed signature
+	scope := dateStamp + "/" + defaultRegion + "/s3/aws4_request"
+
+	// Build canonical request for seed signature
+	hashedPayload := "STREAMING-AWS4-HMAC-SHA256-PAYLOAD"
+	canonicalHeaders := "content-encoding:aws-chunked\n" +
+		"host:s3.amazonaws.com\n" +
+		"x-amz-content-sha256:" + hashedPayload + "\n" +
+		"x-amz-date:" + amzDate + "\n" +
+		"x-amz-decoded-content-length:1024\n"
+	signedHeaders := "content-encoding;host;x-amz-content-sha256;x-amz-date;x-amz-decoded-content-length"
+
+	canonicalRequest := "PUT\n" +
+		"/test-bucket/test-object\n" +
+		"\n" +
+		canonicalHeaders + "\n" +
+		signedHeaders + "\n" +
+		hashedPayload
+
+	canonicalRequestHash := getSHA256Hash([]byte(canonicalRequest))
+	stringToSign := "AWS4-HMAC-SHA256\n" + amzDate + "\n" + scope + "\n" + canonicalRequestHash
+
+	signingKey := getSigningKey(defaultSecretAccessKey, dateStamp, defaultRegion, "s3")
+	seedSignature := getSignature(signingKey, stringToSign)
+
+	// Calculate chunk signature (correct)
+	chunk1Hash := getSHA256Hash([]byte(chunk1Data))
+	chunk1StringToSign := "AWS4-HMAC-SHA256-PAYLOAD\n" + amzDate + "\n" + scope + "\n" +
+		seedSignature + "\n" + emptySHA256 + "\n" + chunk1Hash
+	chunk1Signature := getSignature(signingKey, chunk1StringToSign)
+
+	// Calculate final signature (correct)
+	finalStringToSign := "AWS4-HMAC-SHA256-PAYLOAD\n" + amzDate + "\n" + scope + "\n" +
+		chunk1Signature + "\n" + emptySHA256 + "\n" + emptySHA256
+	finalSignature := getSignature(signingKey, finalStringToSign)
+
+	// Build the chunked payload with INTENTIONALLY WRONG chunk signature
+	// We'll use a modified signature to simulate a tampered request
+	wrongChunkSignature := strings.Replace(chunk1Signature, "a", "b", 1)
+	payload := fmt.Sprintf("400;chunk-signature=%s\r\n%s\r\n", wrongChunkSignature, chunk1Data) +
+		fmt.Sprintf("0;chunk-signature=%s\r\n\r\n", finalSignature)
+
+	// Create the request
+	req, err := http.NewRequest("PUT", "http://s3.amazonaws.com/test-bucket/test-object",
+		bytes.NewReader([]byte(payload)))
+	assert.NoError(t, err)
+
+	req.Header.Set("Host", "s3.amazonaws.com")
+	req.Header.Set("x-amz-date", amzDate)
+	req.Header.Set("x-amz-content-sha256", hashedPayload)
+	req.Header.Set("Content-Encoding", "aws-chunked")
+	req.Header.Set("x-amz-decoded-content-length", "1024")
+
+	authHeader := fmt.Sprintf("AWS4-HMAC-SHA256 Credential=%s/%s, SignedHeaders=%s, Signature=%s",
+		defaultAccessKeyId, scope, signedHeaders, seedSignature)
+	req.Header.Set("Authorization", authHeader)
+
+	// Test the chunked reader - it should be created successfully
+	reader, errCode := iam.newChunkedReader(req)
+	assert.Equal(t, s3err.ErrNone, errCode)
+	assert.NotNil(t, reader)
+
+	// Try to read the payload - this should fail with signature validation error
+	_, err = io.ReadAll(reader)
+	assert.Error(t, err, "Expected error when reading chunk with invalid signature")
+	assert.Contains(t, err.Error(), "chunk signature does not match", "Error should indicate chunk signature mismatch")
+}
diff --git a/weed/s3api/s3err/s3api_errors.go b/weed/s3api/s3err/s3api_errors.go
index 0d354ee8c..762289bce 100644
--- a/weed/s3api/s3err/s3api_errors.go
+++ b/weed/s3api/s3err/s3api_errors.go
@@ -102,6 +102,7 @@ const (
 	ErrContentSHA256Mismatch
 	ErrInvalidAccessKeyID
 	ErrRequestNotReadyYet
+	ErrRequestTimeTooSkewed
 	ErrMissingDateHeader
 	ErrInvalidRequest
 	ErrAuthNotSetup
@@ -432,6 +433,12 @@ var errorCodeResponse = map[ErrorCode]APIError{
 		HTTPStatusCode: http.StatusForbidden,
 	},
 
+	ErrRequestTimeTooSkewed: {
+		Code:           "RequestTimeTooSkewed",
+		Description:    "The difference between the request time and the server's time is too large.",
+		HTTPStatusCode: http.StatusForbidden,
+	},
+
 	ErrSignatureDoesNotMatch: {
 		Code:           "SignatureDoesNotMatch",
 		Description:    "The request signature we calculated does not match the signature you provided. Check your key and signing method.",