Sharing key increase complexity

src/backend/middlewares/SharingMWs.ts

@@ -83,14 +83,14 @@ export class SharingMWs {
       );
     }
 
-    let sharingKey = SharingMWs.generateKey();
+    let sharingKey = SharingMWs.generateKey(Config.Sharing.sharingKeyLength);
 
     // create one not yet used
     // eslint-disable-next-line no-constant-condition
     while (true) {
       try {
         await ObjectManagers.getInstance().SharingManager.findOne(sharingKey);
-        sharingKey = this.generateKey();
+        sharingKey = this.generateKey(Config.Sharing.sharingKeyLength);
       } catch (err) {
         break;
       }
@@ -279,13 +279,14 @@ export class SharingMWs {
     }
   }
 
-  private static generateKey(): string {
-    function s4(): string {
-      return Math.floor((1 + Math.random()) * 0x10000)
-        .toString(16)
-        .substring(1);
+  private static generateKey(length:number): string {
+    function randomInt(max:number): number {
+      return Math.floor(Math.random() * max);
     }
-
-    return s4() + s4();
+    const characters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
+    return [...Array(length).keys()].reduce(
+      (result) => result + characters.charAt(randomInt(characters.length)),
+      ""
+    );
   }
 }

src/common/config/public/ClientConfig.ts

@@ -304,6 +304,16 @@ export class ClientSharingConfig {
     description: $localize`Requires password protected sharing links.`,
   })
   passwordRequired: boolean = false;
+  @ConfigProperty({
+    type: 'unsignedInt', min: 8, max: 64,
+    tags:
+      {
+        name: $localize`Sharing key length`,
+        priority: ConfigPriority.underTheHood
+      },
+    description: $localize`The longer the keys are, the harder they are to guess. Changing this number won't invalidate existing sharing.`,
+  })
+  sharingKeyLength: number = 32;
 }
 
 @SubConfigClass({tags: {client: true}, softReadonly: true})

src/frontend/app/ui/gallery/share/share.gallery.component.css

@@ -32,3 +32,16 @@ a.list-shares-button {
 a.list-shares-button:hover {
   text-decoration: underline;
 }
+
+.ellipsisContainer {
+  position: relative;
+}
+
+.ellipsisText {
+  position: absolute;
+  left: 0;
+  right: 0;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}

src/frontend/app/ui/gallery/share/share.gallery.component.html

@@ -147,7 +147,7 @@ <h5 class="modal-title" i18n>Share</h5>
       </thead>
       <tbody>
       <tr *ngFor="let share of activeShares">
-        <td><a [href]="sharingService.getUrl(share)">{{share.sharingKey}}</a></td>
+        <td class="ellipsisContainer"><a [href]="sharingService.getUrl(share)" class="ellipsisText">{{share.sharingKey}}</a></td>
         <td *ngIf="IsAdmin">{{share.creator.name}}</td>
         <td>{{share.expires | date}}</td>
         <td>

src/frontend/app/ui/settings/sharings-list/sharings-list.component.css

@@ -0,0 +1,12 @@
+.ellipsisContainer {
+    position: relative;
+}
+
+.ellipsisText {
+    position: absolute;
+    left: 0;
+    right: 0;
+    overflow: hidden;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+}

src/frontend/app/ui/settings/sharings-list/sharings-list.component.html

@@ -20,7 +20,7 @@ <h5 i18n>Active shares</h5>
       </thead>
       <tbody>
       <tr *ngFor="let share of shares">
-        <td><a [href]="sharingService.getUrl(share)">{{share.sharingKey}}</a></td>
+        <td class="ellipsisContainer"><a [href]="sharingService.getUrl(share)" class="ellipsisText">{{share.sharingKey}}</a></td>
         <td>{{share.path}}</td>
         <td>{{share.creator.name}}</td>
         <td>{{share.expires | date}}</td>