fix: refactoring previous fix in attempt to address ongoing issues

See #211 and #215

README.md

@@ -49,6 +49,12 @@ docker run \
   ghcr.io/hacdias/webdav -c /config.yml
 ```
 
+If you are using [fail2ban](#fail2ban-setup), it would be helpful to add the parameters listed below. They will assist in analyzing the log.
+```bash
+--log-driver journald \
+--name webdav \
+```
+
 ## Configuration
 
 The configuration can be provided as a YAML, JSON or TOML file. Below is an example of a YAML configuration file with all the options available, as well as what they mean.
@@ -139,6 +145,8 @@ users:
   - username: admin
     password: admin
   # Example 'john' user with bcrypt encrypted password, with custom directory.
+  # You can generate a bcrypt-encrypted password by using the 'webdav bcrypt'
+  # command lint utility.
   - username: john
     password: "{bcrypt}$2y$10$zEP6oofmXFeHaeMfBNLnP.DO8m.H.Mwhd24/TOX2MWLxAExXi4qgi"
     directory: /another/path
@@ -221,10 +229,8 @@ before = common.conf
 
 [Definition]
 # Failregex to match "invalid password" and extract remote_address only
-failregex = ^.*invalid password\s*\{.*"remote_address":\s*"<HOST>"\s*\}
-
-# Failregex to match "invalid username" and extract remote_address only (if applicable)
-failregex += ^.*invalid username\s*\{.*"remote_address":\s*"<HOST>"\s*\}
+failregex = ^.*invalid password\s*\{.*"remote_address":\s*"<HOST>:\d+"\s*\}
+            ^.*invalid username\s*\{.*"remote_address":\s*"<HOST>:\d+"\s*\}
 
 ignoreregex =
 ```
@@ -249,6 +255,8 @@ ignoreself = false
 - Replace `[your_port]` with the port your WebDAV server is running on.
 - Replace `[your_log_path]` with the path to your WebDAV log file.
 
+If you use it with Docker and `--log-driver journald`, replace `logpath` with `journalmatch = CONTAINER_NAME=[your_container_name]`
+
 #### Final Steps
 
 1. Restart Fail2Ban to apply these configurations:

cmd/bcrypt.go

@@ -0,0 +1,49 @@
+package cmd
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/spf13/cobra"
+	"golang.org/x/crypto/bcrypt"
+)
+
+func init() {
+	flags := bcryptCmd.Flags()
+	flags.IntP("cost", "c", bcrypt.DefaultCost, "cost used to generate password, higher cost leads to slower verification times")
+
+	rootCmd.AddCommand(bcryptCmd)
+}
+
+var bcryptCmd = &cobra.Command{
+	Use:   "bcrypt",
+	Short: "Generate a bcrypt encrypted password",
+	Args:  cobra.ExactArgs(1),
+	RunE: func(cmd *cobra.Command, args []string) error {
+		cost, err := cmd.Flags().GetInt("cost")
+		if err != nil {
+			return err
+		}
+
+		if cost < bcrypt.MinCost {
+			return fmt.Errorf("given cost cannot be under minimum cost of %d", bcrypt.MinCost)
+		}
+
+		if cost > bcrypt.MaxCost {
+			return fmt.Errorf("given cost cannot be over maximum cost of %d", bcrypt.MaxCost)
+		}
+
+		pwd := args[0]
+		if pwd == "" {
+			return errors.New("password argument must not be empty")
+		}
+
+		hash, err := bcrypt.GenerateFromPassword([]byte(pwd), cost)
+		if err != nil {
+			return err
+		}
+
+		fmt.Println(string(hash))
+		return nil
+	},
+}

lib/handler.go

@@ -2,7 +2,6 @@ package lib
 
 import (
 	"net/http"
-	"net/url"
 	"os"
 	"strings"
 
@@ -116,21 +115,16 @@ func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		zap.L().Info("user authorized", zap.String("username", username), zap.String("remote_address", remoteAddr))
 	}
 
-	// Cleanup destination header if it's present by stripping out the prefix
-	// and only keeping the path.
-	if destination := r.Header.Get("Destination"); destination != "" {
-		u, err := url.Parse(destination)
-		if err == nil {
-			destination = strings.TrimPrefix(u.Path, user.Prefix)
-			if !strings.HasPrefix(destination, "/") {
-				destination = "/" + destination
-			}
-			r.Header.Set("Destination", destination)
-		}
+	// Convert the HTTP request into an internal request type
+	req, err := newRequest(r, h.user.Prefix)
+	if err != nil {
+		zap.L().Info("invalid request path or destination", zap.Error(err))
+		http.Error(w, "Invalid request path or destination", http.StatusBadRequest)
+		return
 	}
 
 	// Checks for user permissions relatively to this PATH.
-	allowed := user.Allowed(r, func(filename string) bool {
+	allowed := user.Allowed(req, func(filename string) bool {
 		_, err := user.FileSystem.Stat(r.Context(), filename)
 		return !os.IsNotExist(err)
 	})

lib/permissions.go

@@ -3,7 +3,6 @@ package lib
 import (
 	"errors"
 	"fmt"
-	"net/http"
 	"path/filepath"
 	"regexp"
 	"strings"
@@ -51,12 +50,12 @@ type UserPermissions struct {
 }
 
 // Allowed checks if the user has permission to access a directory/file
-func (p UserPermissions) Allowed(r *http.Request, fileExists func(string) bool) bool {
+func (p UserPermissions) Allowed(r *request, fileExists func(string) bool) bool {
 	// For COPY and MOVE requests, we first check the permissions for the destination
 	// path. As soon as a rule matches and does not allow the operation at the destination,
 	// we fail immediately. If no rule matches, we check the global permissions.
-	if r.Method == "COPY" || r.Method == "MOVE" {
-		dst := r.Header.Get("Destination")
+	if r.method == "COPY" || r.method == "MOVE" {
+		dst := r.destination
 
 		for i := len(p.Rules) - 1; i >= 0; i-- {
 			if p.Rules[i].Matches(dst) {
@@ -77,7 +76,7 @@ func (p UserPermissions) Allowed(r *http.Request, fileExists func(string) bool)
 	// Go through rules beginning from the last one, and check the permissions at
 	// the source. The first matched rule returns.
 	for i := len(p.Rules) - 1; i >= 0; i-- {
-		if p.Rules[i].Matches(r.URL.Path) {
+		if p.Rules[i].Matches(r.path) {
 			return p.Rules[i].Permissions.Allowed(r, fileExists)
 		}
 	}
@@ -142,8 +141,8 @@ func (p *Permissions) UnmarshalText(data []byte) error {
 
 // Allowed returns whether this permission set has permissions to execute this
 // request in the source directory. This applies to all requests with all methods.
-func (p Permissions) Allowed(r *http.Request, fileExists func(string) bool) bool {
-	switch r.Method {
+func (p Permissions) Allowed(r *request, fileExists func(string) bool) bool {
+	switch r.method {
 	case "GET", "HEAD", "OPTIONS", "POST", "PROPFIND":
 		// Note: POST backend implementation just returns the same thing as GET.
 		return p.Read
@@ -152,7 +151,7 @@ func (p Permissions) Allowed(r *http.Request, fileExists func(string) bool) bool
 	case "PROPPATCH":
 		return p.Update
 	case "PUT":
-		if fileExists(r.URL.Path) {
+		if fileExists(r.path) {
 			return p.Update
 		} else {
 			return p.Create
@@ -172,10 +171,10 @@ func (p Permissions) Allowed(r *http.Request, fileExists func(string) bool) bool
 
 // AllowedDestination returns whether this permissions set has permissions to execute this
 // request in the destination directory. This only applies for COPY and MOVE requests.
-func (p Permissions) AllowedDestination(r *http.Request, fileExists func(string) bool) bool {
-	switch r.Method {
+func (p Permissions) AllowedDestination(r *request, fileExists func(string) bool) bool {
+	switch r.method {
 	case "COPY", "MOVE":
-		if fileExists(r.Header.Get("Destination")) {
+		if fileExists(r.destination) {
 			return p.Update
 		} else {
 			return p.Create

lib/request.go

@@ -0,0 +1,57 @@
+package lib
+
+import (
+	"errors"
+	"net/http"
+	"net/url"
+	"strings"
+)
+
+type request struct {
+	method      string
+	path        string
+	destination string
+}
+
+func newRequest(r *http.Request, prefix string) (*request, error) {
+	ctx := &request{
+		method: r.Method,
+	}
+
+	if destination := r.Header.Get("Destination"); destination != "" {
+		u, err := url.Parse(destination)
+		if err != nil {
+			return nil, errors.New("invalid destination header")
+		}
+
+		if prefix != "" {
+			destination = strings.TrimPrefix(u.Path, prefix)
+			if len(destination) >= len(u.Path) {
+				return nil, errors.New("invalid url prefix")
+			}
+		}
+
+		if !strings.HasPrefix(destination, "/") {
+			destination = "/" + destination
+		}
+
+		ctx.destination = destination
+	}
+
+	path := r.URL.Path
+
+	if prefix != "" {
+		path = strings.TrimPrefix(r.URL.Path, prefix)
+		if len(path) >= len(r.URL.Path) {
+			return nil, errors.New("invalid url prefix")
+		}
+	}
+
+	if !strings.HasPrefix(path, "/") {
+		path = "/" + path
+	}
+
+	ctx.path = path
+
+	return ctx, nil
+}