From 3e25a62dba3ae330da3ec0a000c97220c95b2512 Mon Sep 17 00:00:00 2001
From: Christopher Ng <chrng8@gmail.com>
Date: Fri, 15 Nov 2024 15:42:18 -0800
Subject: [PATCH 1/2] [wip] feat: Allow updating share token

---
 apps/files_sharing/lib/Controller/ShareAPIController.php | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/apps/files_sharing/lib/Controller/ShareAPIController.php b/apps/files_sharing/lib/Controller/ShareAPIController.php
index 71f73f777a5d9..8bcf2d56da111 100644
--- a/apps/files_sharing/lib/Controller/ShareAPIController.php
+++ b/apps/files_sharing/lib/Controller/ShareAPIController.php
@@ -1163,6 +1163,7 @@ private function hasPermission(int $permissionsSet, int $permissionsToCheck): bo
 	 *                              Considering the share already exists, no mail will be send after the share is updated.
 	 *                              You will have to use the sendMail action to send the mail.
 	 * @param string|null $shareWith New recipient for email shares
+	 * @param string|null $token New token
 	 * @return DataResponse<Http::STATUS_OK, Files_SharingShare, array{}>
 	 * @throws OCSBadRequestException Share could not be updated because the requested changes are invalid
 	 * @throws OCSForbiddenException Missing permissions to update the share
@@ -1183,6 +1184,7 @@ public function updateShare(
 		?string $hideDownload = null,
 		?string $attributes = null,
 		?string $sendMail = null,
+		?string $token = null,
 	): DataResponse {
 		try {
 			$share = $this->getShareById($id);
@@ -1210,7 +1212,8 @@ public function updateShare(
 			$label === null &&
 			$hideDownload === null &&
 			$attributes === null &&
-			$sendMail === null
+			$sendMail === null &&
+			$token === null
 		) {
 			throw new OCSBadRequestException($this->l->t('Wrong or no update parameter given'));
 		}
@@ -1335,6 +1338,10 @@ public function updateShare(
 			} elseif ($sendPasswordByTalk !== null) {
 				$share->setSendPasswordByTalk(false);
 			}
+
+			if ($token !== null) {
+				$share->setToken($token);
+			}
 		}
 
 		// NOT A LINK SHARE

From 948ea9339debd2b7e923ccfe83b9069513617dbb Mon Sep 17 00:00:00 2001
From: Christopher Ng <chrng8@gmail.com>
Date: Fri, 15 Nov 2024 15:42:18 -0800
Subject: [PATCH 2/2] [wip] feat: Edit share token

---
 .../lib/Controller/ShareAPIController.php     | 17 +++++
 apps/files_sharing/src/models/Share.ts        |  7 ++
 .../src/services/TokenService.ts              | 31 ++++++++
 .../src/views/SharingDetailsTab.vue           | 31 ++++++++
 .../Share20/Exception/ShareTokenException.php | 13 ++++
 lib/private/Share20/Manager.php               | 76 ++++++++++---------
 lib/public/Share/IManager.php                 |  9 +++
 7 files changed, 149 insertions(+), 35 deletions(-)
 create mode 100644 apps/files_sharing/src/services/TokenService.ts
 create mode 100644 lib/private/Share20/Exception/ShareTokenException.php

diff --git a/apps/files_sharing/lib/Controller/ShareAPIController.php b/apps/files_sharing/lib/Controller/ShareAPIController.php
index 8bcf2d56da111..f1dbcb8309744 100644
--- a/apps/files_sharing/lib/Controller/ShareAPIController.php
+++ b/apps/files_sharing/lib/Controller/ShareAPIController.php
@@ -21,6 +21,7 @@
 use OCA\GlobalSiteSelector\Service\SlaveService;
 use OCP\App\IAppManager;
 use OCP\AppFramework\Http;
+use OCP\AppFramework\Http\Attribute\ApiRoute;
 use OCP\AppFramework\Http\Attribute\NoAdminRequired;
 use OCP\AppFramework\Http\Attribute\UserRateLimit;
 use OCP\AppFramework\Http\DataResponse;
@@ -2158,4 +2159,20 @@ public function sendShareEmail(string $id, $password = ''): DataResponse {
 			throw new OCSNotFoundException($this->l->t('Wrong share ID, share does not exist'));
 		}
 	}
+
+	/**
+	 * Get a unique share token
+	 *
+	 * @return DataResponse<Http::STATUS_OK, array{token: string}>
+	 *
+	 * 200: Token generated successfully
+	 */
+	#[ApiRoute('GET', '/api/v1/token')]
+	#[NoAdminRequired]
+	public function getToken(): DataResponse {
+		$token = $this->shareManager->generateToken();
+		return new DataResponse([
+			'token' => $token,
+		]);
+	}
 }
diff --git a/apps/files_sharing/src/models/Share.ts b/apps/files_sharing/src/models/Share.ts
index bfc6357240d2f..28631dc7288cb 100644
--- a/apps/files_sharing/src/models/Share.ts
+++ b/apps/files_sharing/src/models/Share.ts
@@ -192,6 +192,13 @@ export default class Share {
 		return this._share.token
 	}
 
+	/**
+	 * Set the public share token
+	 */
+	set token(token: string) {
+		this._share.token = token
+	}
+
 	/**
 	 * Get the share note if any
 	 */
diff --git a/apps/files_sharing/src/services/TokenService.ts b/apps/files_sharing/src/services/TokenService.ts
new file mode 100644
index 0000000000000..0ec3b27f67a24
--- /dev/null
+++ b/apps/files_sharing/src/services/TokenService.ts
@@ -0,0 +1,31 @@
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+import axios from '@nextcloud/axios'
+import { generateUrl } from '@nextcloud/router'
+import logger from './logger.ts'
+
+interface TokenData {
+	token: string,
+}
+
+export const generateToken = async (): Promise<null | string> => {
+	try {
+		const { data } = await axios.get<TokenData>(generateUrl('/api/v1/token'))
+		return data.token
+	} catch (error) {
+		logger.error('Failed to get token from server, falling back to client-side generation', { error })
+
+		const chars = 'abcdefgijkmnopqrstwxyzABCDEFGHJKLMNPQRSTWXYZ23456789'
+		const array = new Uint8Array(10)
+		const ratio = chars.length / 255
+		window.crypto.getRandomValues(array)
+		let token = ''
+		for (let i = 0; i < array.length; i++) {
+			token += chars.charAt(array[i] * ratio)
+		}
+		return token
+	}
+}
diff --git a/apps/files_sharing/src/views/SharingDetailsTab.vue b/apps/files_sharing/src/views/SharingDetailsTab.vue
index 0878c5d289d54..05be81d7a649f 100644
--- a/apps/files_sharing/src/views/SharingDetailsTab.vue
+++ b/apps/files_sharing/src/views/SharingDetailsTab.vue
@@ -105,9 +105,22 @@
 				role="region">
 				<section>
 					<NcInputField v-if="isPublicShare"
+						class="sharingTabDetailsView__label"
 						autocomplete="off"
 						:label="t('files_sharing', 'Share label')"
 						:value.sync="share.label" />
+					<NcInputField v-if="isPublicShare && !isNewShare"
+						autocomplete="off"
+						:label="t('files_sharing', 'Link token')"
+						:helper-text="tokenHelperText"
+						show-trailing-button
+						:trailing-button-label="t('files_sharing', 'Generate new token')"
+						@trailing-button-click="generateNewToken"
+						:value.sync="share.token">
+						<template #trailing-button-icon>
+							<Reload />
+						</template>
+					</NcInputField>
 					<template v-if="isPublicShare">
 						<NcCheckboxRadioSwitch :checked.sync="isPasswordProtected" :disabled="isPasswordEnforced">
 							{{ t('files_sharing', 'Set password') }}
@@ -271,6 +284,7 @@ import UploadIcon from 'vue-material-design-icons/Upload.vue'
 import MenuDownIcon from 'vue-material-design-icons/MenuDown.vue'
 import MenuUpIcon from 'vue-material-design-icons/MenuUp.vue'
 import DotsHorizontalIcon from 'vue-material-design-icons/DotsHorizontal.vue'
+import Reload from 'vue-material-design-icons/Reload.vue'
 
 import ExternalShareAction from '../components/ExternalShareAction.vue'
 
@@ -279,6 +293,7 @@ import Share from '../models/Share.ts'
 import ShareRequests from '../mixins/ShareRequests.js'
 import ShareTypes from '../mixins/ShareTypes.js'
 import SharesMixin from '../mixins/SharesMixin.js'
+import { generateToken } from '../services/TokenService.ts'
 import logger from '../services/logger.ts'
 
 import {
@@ -311,6 +326,7 @@ export default {
 		MenuDownIcon,
 		MenuUpIcon,
 		DotsHorizontalIcon,
+		Reload,
 	},
 	mixins: [ShareTypes, ShareRequests, SharesMixin],
 	props: {
@@ -557,6 +573,13 @@ export default {
 			return t('files_sharing', 'Update share')
 
 		},
+
+		tokenHelperText() {
+			return t('files_sharing', 'Set the public link token. Access the share at /s/{token}', {
+				token: this.share.token || '<token>',
+			}, undefined, { escape: false, sanitize: false })
+		},
+
 		/**
 		 * Can the sharer set whether the sharee can edit the file ?
 		 *
@@ -763,6 +786,10 @@ export default {
 	},
 
 	methods: {
+		generateNewToken() {
+			this.share.token = generateToken()
+		},
+
 		updateAtomicPermissions({
 			isReadChecked = this.hasRead,
 			isEditChecked = this.canEdit,
@@ -1176,6 +1203,10 @@ export default {
 		}
 	}
 
+	&__label {
+		padding-block-end: 6px;
+	}
+
 	&__delete {
 		>button:first-child {
 			color: rgb(223, 7, 7);
diff --git a/lib/private/Share20/Exception/ShareTokenException.php b/lib/private/Share20/Exception/ShareTokenException.php
new file mode 100644
index 0000000000000..23e1999dc5c74
--- /dev/null
+++ b/lib/private/Share20/Exception/ShareTokenException.php
@@ -0,0 +1,13 @@
+<?php
+
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OC\Share20\Exception;
+
+use Exception;
+
+class ShareTokenException extends Exception {
+}
diff --git a/lib/private/Share20/Manager.php b/lib/private/Share20/Manager.php
index 4856c051307a9..5c75248f9f052 100644
--- a/lib/private/Share20/Manager.php
+++ b/lib/private/Share20/Manager.php
@@ -10,6 +10,7 @@
 use OC\Files\Mount\MoveableMount;
 use OC\KnownUser\KnownUserService;
 use OC\Share20\Exception\ProviderException;
+use OC\Share20\Exception\ShareTokenException;
 use OCA\Files_Sharing\AppInfo\Application;
 use OCA\Files_Sharing\SharedStorage;
 use OCP\EventDispatcher\IEventDispatcher;
@@ -657,41 +658,7 @@ public function createShare(IShare $share) {
 				$this->linkCreateChecks($share);
 				$this->setLinkParent($share);
 
-				// Initial token length
-				$tokenLength = \OC\Share\Helper::getTokenLength();
-
-				do {
-					$tokenExists = false;
-
-					for ($i = 0; $i <= 2; $i++) {
-						// Generate a new token
-						$token = $this->secureRandom->generate(
-							$tokenLength,
-							\OCP\Security\ISecureRandom::CHAR_HUMAN_READABLE
-						);
-
-						try {
-							// Try to fetch a share with the generated token
-							$this->getShareByToken($token);
-							$tokenExists = true; // Token exists, we need to try again
-						} catch (\OCP\Share\Exceptions\ShareNotFound $e) {
-							// Token is unique, exit the loop
-							$tokenExists = false;
-							break;
-						}
-					}
-
-					// If we've reached the maximum attempts and the token still exists, increase the token length
-					if ($tokenExists) {
-						$tokenLength++;
-
-						// Check if the token length exceeds the maximum allowed length
-						if ($tokenLength > \OC\Share\Constants::MAX_TOKEN_LENGTH) {
-							throw new \Exception('Unable to generate a unique share token. Maximum token length exceeded.');
-						}
-					}
-				} while ($tokenExists);
-
+				$token = $this->generateToken();
 				// Set the unique token
 				$share->setToken($token);
 
@@ -1992,4 +1959,43 @@ public function getAllShares(): iterable {
 			yield from $provider->getAllShares();
 		}
 	}
+
+	public function generateToken(): string {
+		// Initial token length
+		$tokenLength = \OC\Share\Helper::getTokenLength();
+
+		do {
+			$tokenExists = false;
+
+			for ($i = 0; $i <= 2; $i++) {
+				// Generate a new token
+				$token = $this->secureRandom->generate(
+					$tokenLength,
+					ISecureRandom::CHAR_HUMAN_READABLE,
+				);
+
+				try {
+					// Try to fetch a share with the generated token
+					$this->getShareByToken($token);
+					$tokenExists = true; // Token exists, we need to try again
+				} catch (ShareNotFound $e) {
+					// Token is unique, exit the loop
+					$tokenExists = false;
+					break;
+				}
+			}
+
+			// If we've reached the maximum attempts and the token still exists, increase the token length
+			if ($tokenExists) {
+				$tokenLength++;
+
+				// Check if the token length exceeds the maximum allowed length
+				if ($tokenLength > \OC\Share\Constants::MAX_TOKEN_LENGTH) {
+					throw new ShareTokenException('Unable to generate a unique share token. Maximum token length exceeded.');
+				}
+			}
+		} while ($tokenExists);
+
+		return $token;
+	}
 }
diff --git a/lib/public/Share/IManager.php b/lib/public/Share/IManager.php
index b07bc8f80515e..cc54d6e2e2efb 100644
--- a/lib/public/Share/IManager.php
+++ b/lib/public/Share/IManager.php
@@ -7,6 +7,7 @@
  */
 namespace OCP\Share;
 
+use OC\Share20\Exception\ShareTokenException;
 use OCP\Files\Folder;
 use OCP\Files\Node;
 
@@ -519,4 +520,12 @@ public function registerShareProvider(string $shareProviderClass): void;
 	 * @since 18.0.0
 	 */
 	public function getAllShares(): iterable;
+
+	/**
+	 * Generate a unique share token
+	 *
+	 * @throws ShareTokenException Failed to generate a unique token
+	 * @since 31.0.0
+	 */
+	public function generateToken(): string;
 }