Fix prefix URL routing for encoded CIDR notation

Change route from wildcard /prefix/* to explicit /prefix/{prefix}/{len}
to properly handle URL-encoded IPv6 addresses with CIDR notation.

- Separate prefix and length into individual path parameters
- Add prefixURL template function for generating correct links
- Remove url.QueryUnescape from handlers (chi handles decoding)

internal/server/handlers.go

@@ -7,7 +7,6 @@ import (
 	"errors"
 	"net"
 	"net/http"
-	"net/url"
 	"runtime"
 	"sort"
 	"strconv"
@@ -736,21 +735,18 @@ func (s *Server) handleASDetailJSON() http.HandlerFunc {
 // handlePrefixDetailJSON returns prefix details as JSON
 func (s *Server) handlePrefixDetailJSON() http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
-		// Get wildcard parameter (everything after /prefix/)
-		prefixParam := chi.URLParam(r, "*")
-		if prefixParam == "" {
-			writeJSONError(w, http.StatusBadRequest, "Prefix parameter is required")
+		// Get prefix and length from URL params
+		prefixParam := chi.URLParam(r, "prefix")
+		lenParam := chi.URLParam(r, "len")
+
+		if prefixParam == "" || lenParam == "" {
+			writeJSONError(w, http.StatusBadRequest, "Prefix and length parameters are required")
 
 			return
 		}
 
-		// URL decode the prefix parameter
-		prefix, err := url.QueryUnescape(prefixParam)
-		if err != nil {
-			writeJSONError(w, http.StatusBadRequest, "Invalid prefix parameter")
-
-			return
-		}
+		// Combine prefix and length into CIDR notation
+		prefix := prefixParam + "/" + lenParam
 
 		routes, err := s.db.GetPrefixDetailsContext(r.Context(), prefix)
 		if err != nil {
@@ -903,21 +899,18 @@ func (s *Server) handleASDetail() http.HandlerFunc {
 // handlePrefixDetail returns a handler that serves the prefix detail HTML page
 func (s *Server) handlePrefixDetail() http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
-		// Get wildcard parameter (everything after /prefix/)
-		prefixParam := chi.URLParam(r, "*")
-		if prefixParam == "" {
-			http.Error(w, "Prefix parameter is required", http.StatusBadRequest)
+		// Get prefix and length from URL params
+		prefixParam := chi.URLParam(r, "prefix")
+		lenParam := chi.URLParam(r, "len")
+
+		if prefixParam == "" || lenParam == "" {
+			http.Error(w, "Prefix and length parameters are required", http.StatusBadRequest)
 
 			return
 		}
 
-		// URL decode the prefix parameter
-		prefix, err := url.QueryUnescape(prefixParam)
-		if err != nil {
-			http.Error(w, "Invalid prefix parameter", http.StatusBadRequest)
-
-			return
-		}
+		// Combine prefix and length into CIDR notation
+		prefix := prefixParam + "/" + lenParam
 
 		routes, err := s.db.GetPrefixDetailsContext(r.Context(), prefix)
 		if err != nil {

internal/server/routes.go

@@ -28,7 +28,7 @@ func (s *Server) setupRoutes() {
 
 	// AS and prefix detail pages
 	r.Get("/as/{asn}", s.handleASDetail())
-	r.Get("/prefix/*", s.handlePrefixDetail())
+	r.Get("/prefix/{prefix}/{len}", s.handlePrefixDetail())
 	r.Get("/prefixlength/{length}", s.handlePrefixLength())
 	r.Get("/prefixlength6/{length}", s.handlePrefixLength6())
 
@@ -45,7 +45,7 @@ func (s *Server) setupRoutes() {
 		r.Get("/stats", s.handleStats())
 		r.Get("/ip/{ip}", s.handleIPLookup())
 		r.Get("/as/{asn}", s.handleASDetailJSON())
-		r.Get("/prefix/*", s.handlePrefixDetailJSON())
+		r.Get("/prefix/{prefix}/{len}", s.handlePrefixDetailJSON())
 	})
 
 	s.router = r

internal/templates/as_detail.html

@@ -182,7 +182,7 @@
                 <tbody>
                     {{range .IPv4Prefixes}}
                     <tr>
-                        <td><a href="/prefix/{{.Prefix | urlEncode}}" class="prefix-link">{{.Prefix}}</a></td>
+                        <td><a href="{{.Prefix | prefixURL}}" class="prefix-link">{{.Prefix}}</a></td>
                         <td>/{{.MaskLength}}</td>
                         <td>{{.LastUpdated.Format "2006-01-02 15:04:05"}}</td>
                         <td class="age">{{.LastUpdated | timeSince}}</td>
@@ -211,7 +211,7 @@
                 <tbody>
                     {{range .IPv6Prefixes}}
                     <tr>
-                        <td><a href="/prefix/{{.Prefix | urlEncode}}" class="prefix-link">{{.Prefix}}</a></td>
+                        <td><a href="{{.Prefix | prefixURL}}" class="prefix-link">{{.Prefix}}</a></td>
                         <td>/{{.MaskLength}}</td>
                         <td>{{.LastUpdated.Format "2006-01-02 15:04:05"}}</td>
                         <td class="age">{{.LastUpdated | timeSince}}</td>

internal/templates/prefix_length.html

@@ -93,7 +93,7 @@
         <tbody>
             {{ range .Prefixes }}
             <tr>
-                <td><a href="/prefix/{{ .Prefix | urlEncode }}" class="prefix-link">{{ .Prefix }}</a></td>
+                <td><a href="{{ .Prefix | prefixURL }}" class="prefix-link">{{ .Prefix }}</a></td>
                 <td class="age">{{ .Age }}</td>
                 <td>
                     <a href="/as/{{ .OriginASN }}" class="as-link">

internal/templates/templates.go

@@ -5,6 +5,7 @@ import (
 	_ "embed"
 	"html/template"
 	"net/url"
+	"strings"
 	"sync"
 	"time"
 
@@ -45,6 +46,7 @@ var (
 const (
 	hoursPerDay        = 24
 	daysPerMonth       = 30
+	cidrPartCount      = 2 // A CIDR has two parts: prefix and length
 )
 
 // timeSince returns a human-readable duration since the given time
@@ -80,6 +82,20 @@ func timeSince(t time.Time) string {
 	return t.Format("2006-01-02")
 }
 
+// prefixURL generates a URL path for a prefix in CIDR notation.
+// Takes a prefix like "192.168.1.0/24" and returns "/prefix/192.168.1.0/24"
+// with the prefix part URL-encoded to handle IPv6 colons.
+func prefixURL(cidr string) string {
+	// Split CIDR into prefix and length
+	parts := strings.SplitN(cidr, "/", cidrPartCount)
+	if len(parts) != cidrPartCount {
+		// Fallback if no slash found
+		return "/prefix/" + url.PathEscape(cidr) + "/0"
+	}
+
+	return "/prefix/" + url.PathEscape(parts[0]) + "/" + parts[1]
+}
+
 // initTemplates parses all embedded templates
 func initTemplates() {
 	var err error
@@ -90,6 +106,7 @@ func initTemplates() {
 	funcs := template.FuncMap{
 		"timeSince":        timeSince,
 		"urlEncode":        url.QueryEscape,
+		"prefixURL":        prefixURL,
 		"appName":          func() string { return version.Name },
 		"appAuthor":        func() string { return version.Author },
 		"appAuthorURL":     func() string { return version.AuthorURL },