feat: allow to password protect shares (#1252)

This changes allows to password protect shares. It works by:
* Allowing to optionally pass a password when creating a share
* If set, the password + salt that is configured via a new flag will be
  hashed via bcrypt and the hash stored together with the rest of the
  share
* Additionally, a random 96 byte long token gets generated and stored
  as part of the share
* When the backend retrieves an unauthenticated request for a share that
  has authentication configured, it will return a http 401
* The frontend detects this and will show a login prompt
* The actual download links are protected via an url arg that contains
  the previously generated token. This allows us to avoid buffering the
  download in the browser and allows pasting the link without breaking
  it

frontend/src/components/prompts/Share.vue

@@ -1,14 +1,11 @@
 <template>
-  <div class="card floating" id="share">
+  <div class="card floating share__promt__card" id="share">
     <div class="card-title">
       <h2>{{ $t('buttons.share') }}</h2>
     </div>
 
     <div class="card-content">
       <ul>
-        <li v-if="!hasPermanent">
-          <a @click="getPermalink" :aria-label="$t('buttons.permalink')">{{ $t('buttons.permalink') }}</a>
-        </li>
 
         <li v-for="link in links" :key="link.hash">
           <a :href="buildLink(link.hash)" target="_blank">
@@ -27,6 +24,13 @@
             :title="$t('buttons.copyToClipboard')"><i class="material-icons">content_paste</i></button>
         </li>
 
+        <li v-if="!hasPermanent">
+          <div>
+            <input type="password" :placeholder="$t('prompts.optionalPassword')" v-model="passwordPermalink">
+            <a @click="getPermalink" :aria-label="$t('buttons.permalink')">{{ $t('buttons.permalink') }}</a>
+          </div>
+        </li>
+
         <li>
           <input v-focus
             type="number"
@@ -40,6 +44,7 @@
             <option value="hours">{{ $t('time.hours') }}</option>
             <option value="days">{{ $t('time.days') }}</option>
           </select>
+          <input type="password" :placeholder="$t('prompts.optionalPassword')" v-model="password">
           <button class="action"
             @click="submit"
             :aria-label="$t('buttons.create')"
@@ -72,7 +77,9 @@ export default {
       unit: 'hours',
       hasPermanent: false,
       links: [],
-      clip: null
+      clip: null,
+      password: '',
+      passwordPermalink: ''
     }
   },
   computed: {
@@ -121,7 +128,7 @@ export default {
       if (!this.time) return
 
       try {
-        const res = await api.create(this.url, this.time, this.unit)
+        const res = await api.create(this.url, this.password, this.time, this.unit)
         this.links.push(res)
         this.sort()
       } catch (e) {
@@ -130,7 +137,7 @@ export default {
     },
     getPermalink: async function () {
       try {
-        const res = await api.create(this.url)
+        const res = await api.create(this.url, this.passwordPermalink)
         this.links.push(res)
         this.sort()
         this.hasPermanent = true