Minor UX and security fixes. Add documentation.

README.md

@@ -1,12 +1,14 @@
 # Encrypted Dataroom Management (eDRM)
 
-A trustless, encrypted data room where access is enforced on-chain via FHE (Fully Homomorphic Encryption). Nobody can see who has access to what. Documents live on Filecoin via Storacha.
+Trustless, encrypted filesharing where access is enforced via FHE (Fully Homomorphic Encryption). Nobody can see who has access to what. Documents live on Filecoin via Storacha.
 
 ## The Problem
 
 Data rooms are essential to every investment deal, yet the market (\$3-4B TAM, led by Intralinks and Datasite) charges \$15-50k+ per deal for what is fundamentally access control on a file share. 
 
-Often we need to rely on trust assumptions of the vendors and the members that operate on these data rooms. 
+Often we need to rely on trust assumptions of the vendors and the members that operate on these data rooms.
+
+**Alternatively, it's a way to securely share documents with your friends that no-one else can access!**
 
 ## The Solution
 
@@ -38,6 +40,7 @@ For the full encryption flow, key hierarchy, and contract interface, see [Techni
 
 - [Technical Architecture](docs/ARCHITECTURE.md): encryption flow, key hierarchy, storage model, privacy guarantees
 - [Feature Set](docs/FEATURES.md): planned and shipped features
+- [Architecture Decision Records](docs/ADRs/): technical decisions and trade-offs
 
 ## Getting Started
 
@@ -80,12 +83,12 @@ This runs:
 3. **TypeChain**: pulls ABIs from the build artifacts and generates typed bindings
 4. **Vite**: starts the dapp dev server
 
-#### Storacha setup (file storage)
-If it's too much effort to connect storacha ask for keys from: petros@obolos.io
+#### Storacha setup
+If it's too much effort to setup Storacha ask for keys from: petros@obolos.io
 
 The dapp encrypts files client-side and uploads them to Filecoin via [Storacha](https://storacha.network). 
 
-You need an agent key and a delegation proof:
+Make an agent key and a delegation proof:
 
 ```bash
 # 1. Install the CLI
@@ -119,8 +122,7 @@ VITE_STORACHA_PROOF=mAY…
 #### Chain / RPC (optional)
 
 ```env
-# 31337 = Anvil (default), 11155111 = Sepolia, 1 = Mainnet
-VITE_CHAIN_ID=31337
+VITE_CHAIN_ID=31337 # anvil, 11155111 = Sepolia
 VITE_RPC_URL=http://127.0.0.1:8545
 ```
 

contracts/src/EncryptedDataRoom.sol

@@ -19,6 +19,8 @@ contract EncryptedDataRoom is ZamaEthereumConfig {
     error NotParentRoom();
     error IsParentRoom();
     error CannotNestDeeper();
+    error BatchTooLarge();
+    error InvalidAddress();
 
     // Types
     struct Room {
@@ -39,6 +41,7 @@ contract EncryptedDataRoom is ZamaEthereumConfig {
     }
 
     uint256 public constant NO_PARENT = type(uint256).max;
+    uint256 public constant MAX_BATCH_SIZE = 100;
     uint256 public roomCount;
     mapping(uint256 => Room) public rooms;
     mapping(uint256 => mapping(uint256 => Document)) internal _documents;
@@ -74,6 +77,11 @@ contract EncryptedDataRoom is ZamaEthereumConfig {
         _;
     }
 
+    modifier roomExists(uint256 roomId) {
+        if (rooms[roomId].owner == address(0)) revert RoomNotFound();
+        _;
+    }
+
     // Room Management
 
     /// @notice Create a new parent room
@@ -153,6 +161,7 @@ contract EncryptedDataRoom is ZamaEthereumConfig {
         notParentRoom(roomId)
     {
         if (cids.length != names.length || cids.length != wrappedKeys.length) revert LengthMismatch();
+        if (cids.length > MAX_BATCH_SIZE) revert BatchTooLarge();
         for (uint256 i = 0; i < cids.length; i++) {
             uint256 docIndex = rooms[roomId].documentCount++;
             _documents[roomId][docIndex] =
@@ -174,6 +183,7 @@ contract EncryptedDataRoom is ZamaEthereumConfig {
         notParentRoom(roomId)
     {
         if (docIndices.length != newWrappedKeys.length) revert LengthMismatch();
+        if (docIndices.length > MAX_BATCH_SIZE) revert BatchTooLarge();
         for (uint256 i = 0; i < docIndices.length; i++) {
             _documents[roomId][docIndices[i]].wrappedKey = newWrappedKeys[i];
             documentKeyVersion[roomId][docIndices[i]] = roomKeyVersion[roomId];
@@ -190,12 +200,24 @@ contract EncryptedDataRoom is ZamaEthereumConfig {
         onlyRoomOwner(roomId)
         notParentRoom(roomId)
     {
+        if (users.length > MAX_BATCH_SIZE) revert BatchTooLarge();
         for (uint256 i = 0; i < users.length; i++) {
             address user = users[i];
+            if (user == address(0)) revert InvalidAddress();
             if (_isMember[roomId][user]) revert AlreadyMember();
 
-            uint256 idx = rooms[roomId].memberCount++;
-            _members[roomId][idx] = user;
+            // Only allocate a new slot if user was never in this folder before
+            bool existingSlot = false;
+            uint256 count = rooms[roomId].memberCount;
+            for (uint256 j = 0; j < count; j++) {
+                if (_members[roomId][j] == user) {
+                    existingSlot = true;
+                    break;
+                }
+            }
+            if (!existingSlot) {
+                _members[roomId][rooms[roomId].memberCount++] = user;
+            }
             _isMember[roomId][user] = true;
 
             FHE.allow(_roomKey[roomId], user);
@@ -216,6 +238,7 @@ contract EncryptedDataRoom is ZamaEthereumConfig {
         onlyRoomOwner(roomId)
         notParentRoom(roomId)
     {
+        if (users.length > MAX_BATCH_SIZE) revert BatchTooLarge();
         for (uint256 i = 0; i < users.length; i++) {
             address user = users[i];
             if (!_isMember[roomId][user]) revert NotMember();
@@ -234,15 +257,25 @@ contract EncryptedDataRoom is ZamaEthereumConfig {
     /// @param parentId The parent room ID.
     /// @param user Address of the user to grant access.
     function grantAccessToAllFolders(uint256 parentId, address user) external onlyRoomOwner(parentId) {
+        if (user == address(0)) revert InvalidAddress();
         Room storage parent = rooms[parentId];
         if (!parent.isParent) revert NotParentRoom();
 
         for (uint256 i = 0; i < parent.childCount; i++) {
             uint256 roomId = _children[parentId][i];
             if (_isMember[roomId][user]) continue;
 
-            uint256 idx = rooms[roomId].memberCount++;
-            _members[roomId][idx] = user;
+            bool existingSlot = false;
+            uint256 count = rooms[roomId].memberCount;
+            for (uint256 j = 0; j < count; j++) {
+                if (_members[roomId][j] == user) {
+                    existingSlot = true;
+                    break;
+                }
+            }
+            if (!existingSlot) {
+                _members[roomId][rooms[roomId].memberCount++] = user;
+            }
             _isMember[roomId][user] = true;
 
             FHE.allow(_roomKey[roomId], user);
@@ -302,15 +335,21 @@ contract EncryptedDataRoom is ZamaEthereumConfig {
 
     // Views
 
+    /// @notice Check if the caller has access to a folder
+    /// @param roomId The folder to check access for.
+    function hasAccess(uint256 roomId) external view roomExists(roomId) returns (bool) {
+        return _isMember[roomId][msg.sender];
+    }
+
     /// @notice Get your encrypted access flag for a folder.
     /// @param roomId The folder to check access for.
-    function validateAccess(uint256 roomId) external view returns (ebool) {
+    function validateAccess(uint256 roomId) external view roomExists(roomId) returns (ebool) {
         return _access[roomId][msg.sender];
     }
 
     /// @notice Get the encrypted folder key handle. Only decryptable if granted FHE access.
     /// @param roomId The folder to get the key for.
-    function getRoomKey(uint256 roomId) external view notParentRoom(roomId) returns (euint256) {
+    function getRoomKey(uint256 roomId) external view roomExists(roomId) notParentRoom(roomId) returns (euint256) {
         if (!_isMember[roomId][msg.sender]) revert Unauthorized();
         return _roomKey[roomId];
     }
@@ -323,11 +362,12 @@ contract EncryptedDataRoom is ZamaEthereumConfig {
         view
         returns (string memory cid, string memory name, uint256 createdAt, uint256 keyVersion, bytes memory wrappedKey)
     {
+        if (rooms[roomId].owner == address(0)) revert RoomNotFound();
         Document storage doc = _documents[roomId][docIndex];
         return (doc.cid, doc.name, doc.createdAt, documentKeyVersion[roomId][docIndex], doc.wrappedKey);
     }
 
-    /// @notice Get room/folder info.
+    /// @notice Get room/folder info. memberCount reflects only active (non-revoked) members.
     /// @param roomId The room or folder to query.
     function getRoom(uint256 roomId)
         external
@@ -342,14 +382,21 @@ contract EncryptedDataRoom is ZamaEthereumConfig {
             uint256 childCount
         )
     {
+        if (rooms[roomId].owner == address(0)) revert RoomNotFound();
         Room storage room = rooms[roomId];
-        return
-            (room.owner, room.name, room.documentCount, room.memberCount, room.isParent, room.parentId, room.childCount);
+        uint256 active = 0;
+        uint256 total = room.memberCount;
+        for (uint256 i = 0; i < total; i++) {
+            if (_isMember[roomId][_members[roomId][i]]) {
+                active++;
+            }
+        }
+        return (room.owner, room.name, room.documentCount, active, room.isParent, room.parentId, room.childCount);
     }
 
     /// @notice Get all folder IDs under a parent room.
     /// @param parentId The parent room ID.
-    function getFolders(uint256 parentId) external view returns (uint256[] memory) {
+    function getFolders(uint256 parentId) external view roomExists(parentId) returns (uint256[] memory) {
         Room storage parent = rooms[parentId];
         if (!parent.isParent) revert NotParentRoom();
 
@@ -362,13 +409,14 @@ contract EncryptedDataRoom is ZamaEthereumConfig {
 
     /// @notice Get the parent room ID for a folder.
     /// @param roomId The folder ID.
-    function getParentRoom(uint256 roomId) external view returns (uint256) {
+    function getParentRoom(uint256 roomId) external view roomExists(roomId) returns (uint256) {
         return rooms[roomId].parentId;
     }
 
     /// @notice Get active members of a folder.
     /// @param roomId The folder to query.
     function getMembers(uint256 roomId) external view returns (address[] memory) {
+        if (rooms[roomId].owner == address(0)) revert RoomNotFound();
         if (rooms[roomId].owner != msg.sender) revert Unauthorized();
 
         uint256 count = rooms[roomId].memberCount;