1 files changed, 649 insertions, 0 deletions
diff --git a/weed/s3api/cors/cors.go b/weed/s3api/cors/cors.go
new file mode 100644
index 000000000..1eef71b72
--- /dev/null
+++ b/weed/s3api/cors/cors.go
@@ -0,0 +1,649 @@
+package cors
+
+import (
+	"context"
+	"encoding/json"
+	"encoding/xml"
+	"fmt"
+	"net/http"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/seaweedfs/seaweedfs/weed/glog"
+	"github.com/seaweedfs/seaweedfs/weed/pb/filer_pb"
+)
+
+// S3 metadata file name constant to avoid typos and reduce duplication
+const S3MetadataFileName = ".s3metadata"
+
+// CORSRule represents a single CORS rule
+type CORSRule struct {
+	ID             string   `xml:"ID,omitempty" json:"ID,omitempty"`
+	AllowedMethods []string `xml:"AllowedMethod" json:"AllowedMethods"`
+	AllowedOrigins []string `xml:"AllowedOrigin" json:"AllowedOrigins"`
+	AllowedHeaders []string `xml:"AllowedHeader,omitempty" json:"AllowedHeaders,omitempty"`
+	ExposeHeaders  []string `xml:"ExposeHeader,omitempty" json:"ExposeHeaders,omitempty"`
+	MaxAgeSeconds  *int     `xml:"MaxAgeSeconds,omitempty" json:"MaxAgeSeconds,omitempty"`
+}
+
+// CORSConfiguration represents the CORS configuration for a bucket
+type CORSConfiguration struct {
+	XMLName   xml.Name   `xml:"CORSConfiguration"`
+	CORSRules []CORSRule `xml:"CORSRule" json:"CORSRules"`
+}
+
+// CORSRequest represents a CORS request
+type CORSRequest struct {
+	Origin                      string
+	Method                      string
+	RequestHeaders              []string
+	IsPreflightRequest          bool
+	AccessControlRequestMethod  string
+	AccessControlRequestHeaders []string
+}
+
+// CORSResponse represents CORS response headers
+type CORSResponse struct {
+	AllowOrigin      string
+	AllowMethods     string
+	AllowHeaders     string
+	ExposeHeaders    string
+	MaxAge           string
+	AllowCredentials bool
+}
+
+// ValidateConfiguration validates a CORS configuration
+func ValidateConfiguration(config *CORSConfiguration) error {
+	if config == nil {
+		return fmt.Errorf("CORS configuration cannot be nil")
+	}
+
+	if len(config.CORSRules) == 0 {
+		return fmt.Errorf("CORS configuration must have at least one rule")
+	}
+
+	if len(config.CORSRules) > 100 {
+		return fmt.Errorf("CORS configuration cannot have more than 100 rules")
+	}
+
+	for i, rule := range config.CORSRules {
+		if err := validateRule(&rule); err != nil {
+			return fmt.Errorf("invalid CORS rule at index %d: %v", i, err)
+		}
+	}
+
+	return nil
+}
+
+// validateRule validates a single CORS rule
+func validateRule(rule *CORSRule) error {
+	if len(rule.AllowedMethods) == 0 {
+		return fmt.Errorf("AllowedMethods cannot be empty")
+	}
+
+	if len(rule.AllowedOrigins) == 0 {
+		return fmt.Errorf("AllowedOrigins cannot be empty")
+	}
+
+	// Validate allowed methods
+	validMethods := map[string]bool{
+		"GET":    true,
+		"PUT":    true,
+		"POST":   true,
+		"DELETE": true,
+		"HEAD":   true,
+	}
+
+	for _, method := range rule.AllowedMethods {
+		if !validMethods[method] {
+			return fmt.Errorf("invalid HTTP method: %s", method)
+		}
+	}
+
+	// Validate origins
+	for _, origin := range rule.AllowedOrigins {
+		if origin == "*" {
+			continue
+		}
+		if err := validateOrigin(origin); err != nil {
+			return fmt.Errorf("invalid origin %s: %v", origin, err)
+		}
+	}
+
+	// Validate MaxAgeSeconds
+	if rule.MaxAgeSeconds != nil && *rule.MaxAgeSeconds < 0 {
+		return fmt.Errorf("MaxAgeSeconds cannot be negative")
+	}
+
+	return nil
+}
+
+// validateOrigin validates an origin string
+func validateOrigin(origin string) error {
+	if origin == "" {
+		return fmt.Errorf("origin cannot be empty")
+	}
+
+	// Special case: "*" is always valid
+	if origin == "*" {
+		return nil
+	}
+
+	// Count wildcards
+	wildcardCount := strings.Count(origin, "*")
+	if wildcardCount > 1 {
+		return fmt.Errorf("origin can contain at most one wildcard")
+	}
+
+	// If there's a wildcard, it should be in a valid position
+	if wildcardCount == 1 {
+		// Must be in the format: http://*.example.com or https://*.example.com
+		if !strings.HasPrefix(origin, "http://") && !strings.HasPrefix(origin, "https://") {
+			return fmt.Errorf("origin with wildcard must start with http:// or https://")
+		}
+	}
+
+	return nil
+}
+
+// ParseRequest parses an HTTP request to extract CORS information
+func ParseRequest(r *http.Request) *CORSRequest {
+	corsReq := &CORSRequest{
+		Origin: r.Header.Get("Origin"),
+		Method: r.Method,
+	}
+
+	// Check if this is a preflight request
+	if r.Method == "OPTIONS" {
+		corsReq.IsPreflightRequest = true
+		corsReq.AccessControlRequestMethod = r.Header.Get("Access-Control-Request-Method")
+
+		if headers := r.Header.Get("Access-Control-Request-Headers"); headers != "" {
+			corsReq.AccessControlRequestHeaders = strings.Split(headers, ",")
+			for i := range corsReq.AccessControlRequestHeaders {
+				corsReq.AccessControlRequestHeaders[i] = strings.TrimSpace(corsReq.AccessControlRequestHeaders[i])
+			}
+		}
+	}
+
+	return corsReq
+}
+
+// EvaluateRequest evaluates a CORS request against a CORS configuration
+func EvaluateRequest(config *CORSConfiguration, corsReq *CORSRequest) (*CORSResponse, error) {
+	if config == nil || corsReq == nil {
+		return nil, fmt.Errorf("config and corsReq cannot be nil")
+	}
+
+	if corsReq.Origin == "" {
+		return nil, fmt.Errorf("origin header is required for CORS requests")
+	}
+
+	// Find the first rule that matches the origin
+	for _, rule := range config.CORSRules {
+		if matchesOrigin(rule.AllowedOrigins, corsReq.Origin) {
+			// For preflight requests, we need more detailed validation
+			if corsReq.IsPreflightRequest {
+				return buildPreflightResponse(&rule, corsReq), nil
+			} else {
+				// For actual requests, check method
+				if contains(rule.AllowedMethods, corsReq.Method) {
+					return buildResponse(&rule, corsReq), nil
+				}
+			}
+		}
+	}
+
+	return nil, fmt.Errorf("no matching CORS rule found")
+}
+
+// matchesRule checks if a CORS request matches a CORS rule
+func matchesRule(rule *CORSRule, corsReq *CORSRequest) bool {
+	// Check origin - this is the primary matching criterion
+	if !matchesOrigin(rule.AllowedOrigins, corsReq.Origin) {
+		return false
+	}
+
+	// For preflight requests, we need to validate both the requested method and headers
+	if corsReq.IsPreflightRequest {
+		// Check if the requested method is allowed
+		if corsReq.AccessControlRequestMethod != "" {
+			if !contains(rule.AllowedMethods, corsReq.AccessControlRequestMethod) {
+				return false
+			}
+		}
+
+		// Check if all requested headers are allowed
+		if len(corsReq.AccessControlRequestHeaders) > 0 {
+			for _, requestedHeader := range corsReq.AccessControlRequestHeaders {
+				if !matchesHeader(rule.AllowedHeaders, requestedHeader) {
+					return false
+				}
+			}
+		}
+
+		return true
+	}
+
+	// For non-preflight requests, check method matching
+	method := corsReq.Method
+	if !contains(rule.AllowedMethods, method) {
+		return false
+	}
+
+	return true
+}
+
+// matchesOrigin checks if an origin matches any of the allowed origins
+func matchesOrigin(allowedOrigins []string, origin string) bool {
+	for _, allowedOrigin := range allowedOrigins {
+		if allowedOrigin == "*" {
+			return true
+		}
+
+		if allowedOrigin == origin {
+			return true
+		}
+
+		// Check wildcard matching
+		if strings.Contains(allowedOrigin, "*") {
+			if matchesWildcard(allowedOrigin, origin) {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+// matchesWildcard checks if an origin matches a wildcard pattern
+// Uses string manipulation instead of regex for better performance
+func matchesWildcard(pattern, origin string) bool {
+	// Handle simple cases first
+	if pattern == "*" {
+		return true
+	}
+	if pattern == origin {
+		return true
+	}
+
+	// For CORS, we typically only deal with * wildcards (not ? wildcards)
+	// Use string manipulation for * wildcards only (more efficient than regex)
+
+	// Split pattern by wildcards
+	parts := strings.Split(pattern, "*")
+	if len(parts) == 1 {
+		// No wildcards, exact match
+		return pattern == origin
+	}
+
+	// Check if string starts with first part
+	if len(parts[0]) > 0 && !strings.HasPrefix(origin, parts[0]) {
+		return false
+	}
+
+	// Check if string ends with last part
+	if len(parts[len(parts)-1]) > 0 && !strings.HasSuffix(origin, parts[len(parts)-1]) {
+		return false
+	}
+
+	// Check middle parts
+	searchStr := origin
+	if len(parts[0]) > 0 {
+		searchStr = searchStr[len(parts[0]):]
+	}
+	if len(parts[len(parts)-1]) > 0 {
+		searchStr = searchStr[:len(searchStr)-len(parts[len(parts)-1])]
+	}
+
+	for i := 1; i < len(parts)-1; i++ {
+		if len(parts[i]) > 0 {
+			index := strings.Index(searchStr, parts[i])
+			if index == -1 {
+				return false
+			}
+			searchStr = searchStr[index+len(parts[i]):]
+		}
+	}
+
+	return true
+}
+
+// matchesHeader checks if a header matches allowed headers
+func matchesHeader(allowedHeaders []string, header string) bool {
+	if len(allowedHeaders) == 0 {
+		return true // No restrictions
+	}
+
+	for _, allowedHeader := range allowedHeaders {
+		if allowedHeader == "*" {
+			return true
+		}
+
+		if strings.EqualFold(allowedHeader, header) {
+			return true
+		}
+
+		// Check wildcard matching for headers
+		if strings.Contains(allowedHeader, "*") {
+			if matchesWildcard(strings.ToLower(allowedHeader), strings.ToLower(header)) {
+				return true
+			}
+		}
+	}
+
+	return false
+}
+
+// buildPreflightResponse builds a CORS response for preflight requests
+// This function allows partial matches - origin can match while methods/headers may not
+func buildPreflightResponse(rule *CORSRule, corsReq *CORSRequest) *CORSResponse {
+	response := &CORSResponse{
+		AllowOrigin: corsReq.Origin,
+	}
+
+	// Check if the requested method is allowed
+	methodAllowed := corsReq.AccessControlRequestMethod == "" || contains(rule.AllowedMethods, corsReq.AccessControlRequestMethod)
+
+	// Check requested headers
+	var allowedRequestHeaders []string
+	allHeadersAllowed := true
+
+	if len(corsReq.AccessControlRequestHeaders) > 0 {
+		// Check if wildcard is allowed
+		hasWildcard := false
+		for _, header := range rule.AllowedHeaders {
+			if header == "*" {
+				hasWildcard = true
+				break
+			}
+		}
+
+		if hasWildcard {
+			// All requested headers are allowed with wildcard
+			allowedRequestHeaders = corsReq.AccessControlRequestHeaders
+		} else {
+			// Check each requested header individually
+			for _, requestedHeader := range corsReq.AccessControlRequestHeaders {
+				if matchesHeader(rule.AllowedHeaders, requestedHeader) {
+					allowedRequestHeaders = append(allowedRequestHeaders, requestedHeader)
+				} else {
+					allHeadersAllowed = false
+				}
+			}
+		}
+	}
+
+	// Only set method and header info if both method and ALL headers are allowed
+	if methodAllowed && allHeadersAllowed {
+		response.AllowMethods = strings.Join(rule.AllowedMethods, ", ")
+
+		if len(allowedRequestHeaders) > 0 {
+			response.AllowHeaders = strings.Join(allowedRequestHeaders, ", ")
+		}
+
+		// Set exposed headers
+		if len(rule.ExposeHeaders) > 0 {
+			response.ExposeHeaders = strings.Join(rule.ExposeHeaders, ", ")
+		}
+
+		// Set max age
+		if rule.MaxAgeSeconds != nil {
+			response.MaxAge = strconv.Itoa(*rule.MaxAgeSeconds)
+		}
+	}
+
+	return response
+}
+
+// buildResponse builds a CORS response from a matching rule
+func buildResponse(rule *CORSRule, corsReq *CORSRequest) *CORSResponse {
+	response := &CORSResponse{
+		AllowOrigin: corsReq.Origin,
+	}
+
+	// Set allowed methods - for preflight requests, return all allowed methods
+	if corsReq.IsPreflightRequest {
+		response.AllowMethods = strings.Join(rule.AllowedMethods, ", ")
+	} else {
+		// For non-preflight requests, return all allowed methods
+		response.AllowMethods = strings.Join(rule.AllowedMethods, ", ")
+	}
+
+	// Set allowed headers
+	if corsReq.IsPreflightRequest && len(rule.AllowedHeaders) > 0 {
+		// For preflight requests, check if wildcard is allowed
+		hasWildcard := false
+		for _, header := range rule.AllowedHeaders {
+			if header == "*" {
+				hasWildcard = true
+				break
+			}
+		}
+
+		if hasWildcard && len(corsReq.AccessControlRequestHeaders) > 0 {
+			// Return the specific headers that were requested when wildcard is allowed
+			response.AllowHeaders = strings.Join(corsReq.AccessControlRequestHeaders, ", ")
+		} else if len(corsReq.AccessControlRequestHeaders) > 0 {
+			// For non-wildcard cases, return the requested headers (preserving case)
+			// since we already validated they are allowed in matchesRule
+			response.AllowHeaders = strings.Join(corsReq.AccessControlRequestHeaders, ", ")
+		} else {
+			// Fallback to configured headers if no specific headers were requested
+			response.AllowHeaders = strings.Join(rule.AllowedHeaders, ", ")
+		}
+	} else if len(rule.AllowedHeaders) > 0 {
+		// For non-preflight requests, return the allowed headers from the rule
+		response.AllowHeaders = strings.Join(rule.AllowedHeaders, ", ")
+	}
+
+	// Set exposed headers
+	if len(rule.ExposeHeaders) > 0 {
+		response.ExposeHeaders = strings.Join(rule.ExposeHeaders, ", ")
+	}
+
+	// Set max age
+	if rule.MaxAgeSeconds != nil {
+		response.MaxAge = strconv.Itoa(*rule.MaxAgeSeconds)
+	}
+
+	return response
+}
+
+// contains checks if a slice contains a string
+func contains(slice []string, item string) bool {
+	for _, s := range slice {
+		if s == item {
+			return true
+		}
+	}
+	return false
+}
+
+// ApplyHeaders applies CORS headers to an HTTP response
+func ApplyHeaders(w http.ResponseWriter, corsResp *CORSResponse) {
+	if corsResp == nil {
+		return
+	}
+
+	if corsResp.AllowOrigin != "" {
+		w.Header().Set("Access-Control-Allow-Origin", corsResp.AllowOrigin)
+	}
+
+	if corsResp.AllowMethods != "" {
+		w.Header().Set("Access-Control-Allow-Methods", corsResp.AllowMethods)
+	}
+
+	if corsResp.AllowHeaders != "" {
+		w.Header().Set("Access-Control-Allow-Headers", corsResp.AllowHeaders)
+	}
+
+	if corsResp.ExposeHeaders != "" {
+		w.Header().Set("Access-Control-Expose-Headers", corsResp.ExposeHeaders)
+	}
+
+	if corsResp.MaxAge != "" {
+		w.Header().Set("Access-Control-Max-Age", corsResp.MaxAge)
+	}
+
+	if corsResp.AllowCredentials {
+		w.Header().Set("Access-Control-Allow-Credentials", "true")
+	}
+}
+
+// FilerClient interface for dependency injection
+type FilerClient interface {
+	WithFilerClient(streamingMode bool, fn func(filer_pb.SeaweedFilerClient) error) error
+}
+
+// EntryGetter interface for getting filer entries
+type EntryGetter interface {
+	GetEntry(directory, name string) (*filer_pb.Entry, error)
+}
+
+// Storage provides CORS configuration storage operations
+type Storage struct {
+	filerClient FilerClient
+	entryGetter EntryGetter
+	bucketsPath string
+}
+
+// NewStorage creates a new CORS storage instance
+func NewStorage(filerClient FilerClient, entryGetter EntryGetter, bucketsPath string) *Storage {
+	return &Storage{
+		filerClient: filerClient,
+		entryGetter: entryGetter,
+		bucketsPath: bucketsPath,
+	}
+}
+
+// Store stores CORS configuration in the filer
+func (s *Storage) Store(bucket string, config *CORSConfiguration) error {
+	// Store in bucket metadata
+	bucketMetadataPath := filepath.Join(s.bucketsPath, bucket, S3MetadataFileName)
+
+	// Get existing metadata
+	existingEntry, err := s.entryGetter.GetEntry("", bucketMetadataPath)
+	var metadata map[string]interface{}
+
+	if err == nil && existingEntry != nil && len(existingEntry.Content) > 0 {
+		if err := json.Unmarshal(existingEntry.Content, &metadata); err != nil {
+			glog.V(1).Infof("Failed to unmarshal existing metadata: %v", err)
+			metadata = make(map[string]interface{})
+		}
+	} else {
+		metadata = make(map[string]interface{})
+	}
+
+	metadata["cors"] = config
+
+	metadataBytes, err := json.Marshal(metadata)
+	if err != nil {
+		return fmt.Errorf("failed to marshal bucket metadata: %v", err)
+	}
+
+	// Store metadata
+	return s.filerClient.WithFilerClient(false, func(client filer_pb.SeaweedFilerClient) error {
+		request := &filer_pb.CreateEntryRequest{
+			Directory: s.bucketsPath + "/" + bucket,
+			Entry: &filer_pb.Entry{
+				Name:        S3MetadataFileName,
+				IsDirectory: false,
+				Attributes: &filer_pb.FuseAttributes{
+					Crtime:   time.Now().Unix(),
+					Mtime:    time.Now().Unix(),
+					FileMode: 0644,
+				},
+				Content: metadataBytes,
+			},
+		}
+
+		_, err := client.CreateEntry(context.Background(), request)
+		return err
+	})
+}
+
+// Load loads CORS configuration from the filer
+func (s *Storage) Load(bucket string) (*CORSConfiguration, error) {
+	bucketMetadataPath := filepath.Join(s.bucketsPath, bucket, S3MetadataFileName)
+
+	entry, err := s.entryGetter.GetEntry("", bucketMetadataPath)
+	if err != nil || entry == nil {
+		return nil, fmt.Errorf("no CORS configuration found")
+	}
+
+	if len(entry.Content) == 0 {
+		return nil, fmt.Errorf("no CORS configuration found")
+	}
+
+	var metadata map[string]interface{}
+	if err := json.Unmarshal(entry.Content, &metadata); err != nil {
+		return nil, fmt.Errorf("failed to unmarshal metadata: %v", err)
+	}
+
+	corsData, exists := metadata["cors"]
+	if !exists {
+		return nil, fmt.Errorf("no CORS configuration found")
+	}
+
+	// Convert back to CORSConfiguration
+	corsBytes, err := json.Marshal(corsData)
+	if err != nil {
+		return nil, fmt.Errorf("failed to marshal CORS data: %v", err)
+	}
+
+	var config CORSConfiguration
+	if err := json.Unmarshal(corsBytes, &config); err != nil {
+		return nil, fmt.Errorf("failed to unmarshal CORS configuration: %v", err)
+	}
+
+	return &config, nil
+}
+
+// Delete deletes CORS configuration from the filer
+func (s *Storage) Delete(bucket string) error {
+	bucketMetadataPath := filepath.Join(s.bucketsPath, bucket, S3MetadataFileName)
+
+	entry, err := s.entryGetter.GetEntry("", bucketMetadataPath)
+	if err != nil || entry == nil {
+		return nil // Already deleted or doesn't exist
+	}
+
+	var metadata map[string]interface{}
+	if len(entry.Content) > 0 {
+		if err := json.Unmarshal(entry.Content, &metadata); err != nil {
+			return fmt.Errorf("failed to unmarshal metadata: %v", err)
+		}
+	} else {
+		return nil // No metadata to delete
+	}
+
+	// Remove CORS configuration
+	delete(metadata, "cors")
+
+	metadataBytes, err := json.Marshal(metadata)
+	if err != nil {
+		return fmt.Errorf("failed to marshal metadata: %v", err)
+	}
+
+	// Update metadata
+	return s.filerClient.WithFilerClient(false, func(client filer_pb.SeaweedFilerClient) error {
+		request := &filer_pb.CreateEntryRequest{
+			Directory: s.bucketsPath + "/" + bucket,
+			Entry: &filer_pb.Entry{
+				Name:        S3MetadataFileName,
+				IsDirectory: false,
+				Attributes: &filer_pb.FuseAttributes{
+					Crtime:   time.Now().Unix(),
+					Mtime:    time.Now().Unix(),
+					FileMode: 0644,
+				},
+				Content: metadataBytes,
+			},
+		}
+
+		_, err := client.CreateEntry(context.Background(), request)
+		return err
+	})
+}