> ## Documentation Index > Fetch the complete documentation index at: https://docs.zkterm.io/llms.txt > Use this file to discover all available pages before exploring further. # zkStorage > Privacy-first decentralized file storage with ZK proofs ## Overview zkStorage provides encrypted file storage on IPFS with zero-knowledge proofs for password verification. Files are encrypted client-side before upload, ensuring only you can access your data. ## How It Works 1. **Encrypt:** Files are encrypted client-side using AES-256-GCM with a key derived from your password. 2. **Generate Proof:** A Groth16 zkSNARK proof is generated proving you know the password without revealing it. 3. **Upload:** Encrypted file is uploaded to IPFS via Pinata with the proof attached. 4. **Verify:** Download requires verifying the ZK proof to decrypt the file. ## Terminal Commands ### Show Help ```bash theme={null} zk storage help ``` Shows all available zkStorage commands and security details. ### Upload File ```bash theme={null} zk storage upload ``` Opens a file picker for encrypted upload. After selecting a file, you'll be prompted for a password. **Example:** ```bash theme={null} > zk storage upload [File picker opens] Password: ******** Encrypting file (1.2 MB)... Generating ZK proof... Uploading to IPFS... Success! CID: QmXyz123abc456def789 ``` ### List Files ```bash theme={null} zk storage list ``` Shows all your uploaded files with CID, name, size, and date. ```bash theme={null} > zk storage list Your zkStorage Files: [1] document.pdf [ZK] CID: QmXyz123... Size: 1.2 MB Uploaded: Dec 1, 2025 [2] image.png [ZK] CID: QmAbc456... Size: 500 KB Uploaded: Nov 30, 2025 ``` ### Download File ```bash theme={null} zk storage download ``` Downloads and decrypts a file. Requires password for decryption. **Example:** ```bash theme={null} > zk storage download QmXyz123 Password: ******** Verifying ZK proof... Downloading from IPFS... Decrypting file... Saved to: document.pdf ``` ### Share File ```bash theme={null} zk storage share ``` Creates a shareable link with time-limited access. ### File Info ```bash theme={null} zk storage info ``` Shows detailed information about a specific file. ### Delete File ```bash theme={null} zk storage delete ``` Unpins a file from IPFS (removes from Pinata). ## API Reference ### Upload File ```bash theme={null} POST /api/storage/upload Content-Type: multipart/form-data file: encryptedData: iv: salt: commitment: proof: publicSignals: ``` **Response:** ```json theme={null} { "success": true, "cid": "QmXyz123...", "fileId": "uuid", "originalName": "document.pdf", "originalSize": 1234567, "zkEnabled": true } ``` ### List Files ```bash theme={null} GET /api/storage/files ``` **Response:** ```json theme={null} { "files": [ { "id": "uuid", "cid": "QmXyz123...", "originalName": "document.pdf", "originalSize": 1234567, "zkEnabled": true, "createdAt": "2025-12-01T10:00:00Z" } ] } ``` ### Download File ```bash theme={null} POST /api/storage/download Content-Type: application/json { "fileId": "uuid", "proof": {...}, "publicSignals": [...] } ``` **Response:** Binary encrypted file data ### Create Share Link ```bash theme={null} POST /api/storage/share Content-Type: application/json { "fileId": "uuid", "expiresIn": 86400 } ``` **Response:** ```json theme={null} { "shareUrl": "https://zkterm.io/share/abc123", "expiresAt": "2025-12-02T10:00:00Z" } ``` ### Delete File ```bash theme={null} DELETE /api/storage/files/ ``` **Response:** ```json theme={null} { "success": true, "message": "File deleted" } ``` ## Technical Details ### Encryption zkStorage uses **AES-256-GCM** for file encryption: ```typescript theme={null} const key = await crypto.subtle.deriveKey( { name: "PBKDF2", salt, iterations: 100000, hash: "SHA-256" }, passwordKey, { name: "AES-GCM", length: 256 }, false, ["encrypt", "decrypt"] ); const encrypted = await crypto.subtle.encrypt( { name: "AES-GCM", iv }, key, fileData ); ``` ### ZK Proof Generation Groth16 proofs verify password knowledge using Poseidon hash commitments: ```typescript theme={null} const { proof, publicSignals } = await snarkjs.groth16.fullProve( { password: passwordHash }, "circuits/password.wasm", "circuits/password_final.zkey" ); ``` ### IPFS Storage Files are stored on IPFS via Pinata: 1. **Gateway:** gateway.pinata.cloud 2. **Persistence:** Files remain pinned indefinitely 3. **Redundancy:** Multiple IPFS nodes ### File Limits | Limit | Value | | ------------- | --------------- | | Max file size | 100 MB | | Encryption | AES-256-GCM | | Storage | IPFS via Pinata | ## Security Features 1. **Client-Side Encryption:** Files encrypted before leaving your device. 2. **Zero-Knowledge Proofs:** Password verified without revealing it. 3. **AES-256-GCM:** Military-grade authenticated encryption. 4. **SHA-256 Checksums:** Verify file integrity on download. 5. **Time-Limited Sharing:** Share links expire automatically. **Important:** If you forget your password, your files cannot be recovered. There is no password reset. ## Error Handling | Error | Cause | Solution | | ------------------------- | -------------- | ------------------------ | | `Invalid proof` | Wrong password | Enter correct password | | `CID not found` | File unpinned | File no longer available | | `Checksum mismatch` | File corrupted | Re-upload the file | | `Proof generation failed` | Circuit error | Check password format | ## Example: Full Flow ```bash theme={null} # 1. Upload a file > zk storage upload [File picker opens - select secret_document.pdf] Password: ******** Confirm password: ******** Encrypting file (1.2 MB)... Generating Groth16 proof... Uploading to IPFS... Success! CID: QmXyz123abc456def789 # 2. List your files > zk storage list Your zkStorage Files: [1] secret_document.pdf [ZK] CID: QmXyz123... Size: 1.2 MB Uploaded: Dec 1, 2025 # 3. Download later > zk storage download QmXyz123 Password: ******** Verifying proof... Downloading from IPFS... Decrypting... Verifying checksum... Saved to: secret_document.pdf ```