Tempdrop

Single-binary, self-hosted ephemeral file sharing service. Fast, zero-knowledge encrypted, auto-expiring file uploads with zero accounts and zero external database dependencies.

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Features

• Total Zero-Knowledge Encryption: In-browser AES-256-GCM encryption for both file payload bytes and original filenames. Decryption keys stay strictly in the URL fragment hash (#key=...) and are never transmitted to or logged by the server.
• Single Executable: Self-contained Rust binary (Axum + SQLite WAL) with the Svelte 5 frontend compiled directly into the executable via rust-embed.
• Real-Time XHR Upload Progress: Smooth byte-level progress tracking via XMLHttpRequest upload events instead of blocky chunk jumps.
• Chunked Stream Decryption: Memory-safe 32 MiB sliding window stream decryption for multi-gigabyte files.
• SVG QR Code Sharing: Built-in SVG QR code generator on upload completion for mobile share scanning.
• UTC Timestamp Privacy: UTC timestamp formatting (YYYY-MM-DD HH:MM:SS UTC) to eliminate local browser timezone leakage.
• Cloudflare & Reverse Proxy Support: Direct CF-Connecting-IP header support and X-Forwarded-For handling when trust_proxy = true.
• Expiration Controls: Time-to-live (TTL) duration choices and max download count limits.
• Storage Backends: Local disk storage or S3-compatible object storage (AWS S3, Cloudflare R2, MinIO, RustFS) with presigned multipart uploads.
• Automated Janitor: Background task periodically hard-purges expired files, count-exhausted files, and abandoned upload chunks.
• Protections & Headers: Fixed-window rate limiting, disk space guards, Content-Security-Policy, X-Content-Type-Options: nosniff, X-Frame-Options: DENY, and Referrer-Policy: no-referrer.

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Quickstart

Pre-built Binaries

Single-file executables for Linux, Windows, and macOS are published on GitHub Releases:

• Linux: x86_64 (amd64), aarch64 (arm64)
• Windows: x86_64 (amd64), aarch64 (arm64)
• macOS: x86_64 (Intel), aarch64 (Apple Silicon)

# Run binary with default configuration or path flag
./tempdrop -c /path/to/tempdrop.toml

Building from Source

# 1. Build Svelte UI Bundle
cd ui
npm ci
npm run build
cd ..

# 2. Build Release Server Binary
cd server
cargo build --release

The compiled binary will be placed at server/target/release/tempdrop.

Running with Docker

# Build multi-stage Docker image
docker build -t tempdrop:latest .

# Run container
docker run -d -p 8080:8080 -v ./data:/app/data tempdrop:latest

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Configuration Reference

Configure Tempdrop via -c /path/to/tempdrop.toml or environment variables prefixed with FILEHOST_.

Config Key	Env Variable	Default	Description
server.bind	FILEHOST_SERVER_BIND	127.0.0.1	IP address to bind
server.port	FILEHOST_SERVER_PORT	8080	Network port
server.trust_proxy	FILEHOST_SERVER_TRUST_PROXY	false	Read CF-Connecting-IP / X-Forwarded-For headers
storage.backend	FILEHOST_STORAGE_BACKEND	local	Storage backend (local or s3)
storage.root_dir	FILEHOST_STORAGE_ROOT_DIR	./data	Local storage directory
storage.data_dir	FILEHOST_STORAGE_DATA_DIR	./data	Database directory (when storage is s3)
uploads.max_size_bytes	FILEHOST_UPLOADS_MAX_SIZE_BYTES	0	Max file size in bytes (0 = unlimited)
uploads.min_free_bytes	FILEHOST_UPLOADS_MIN_FREE_BYTES	1073741824	Minimum free disk space in bytes (1 GiB)
uploads.max_ttl_seconds	FILEHOST_UPLOADS_MAX_TTL_SECONDS	604800	Max TTL allowed (7 days)
uploads.max_downloads	FILEHOST_UPLOADS_MAX_DOWNLOADS	100	Max download limit allowed
uploads.chunk_size_bytes	FILEHOST_UPLOADS_CHUNK_SIZE_BYTES	33554432	Part chunk size in bytes (32 MiB)
rate_limit.per_min	FILEHOST_RATE_LIMIT_PER_MIN	60	Requests per IP per minute
janitor.interval_seconds	FILEHOST_JANITOR_INTERVAL_SECONDS	60	Sweep interval in seconds

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Storage Backends

Local Storage

[storage]
backend = "local"
root_dir = "./data"

S3 / Cloudflare R2 / RustFS / MinIO

[storage]
backend = "s3"

[storage.s3]
bucket = "my-tempdrop-bucket"
region = "us-east-1"
access_key = "YOUR_ACCESS_KEY"
secret_key = "YOUR_SECRET_KEY"
endpoint = "http://127.0.0.1:9000"
force_path_style = true
presign_ttl_seconds = 900

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Security & Privacy Model

• Payload & Filename AES-256-GCM: Client-side Web Crypto API encrypts file payload bytes and original filenames (enc:<ciphertext_hex>) before upload. Neither server logs, SQLite database, nor S3 object storage see real filenames or contents.
• URL Hash Key Storage: The decryption key is appended to the share link fragment (#key=...). Browsers never transmit URL fragments in HTTP request headers or server paths.
• Cryptographic Tokens: Upload IDs are 12-character Base62 tokens. Upload authorization tokens are 64-character hex secrets.
• Input Sanitization: Filenames are sanitized to prevent CRLF injection, path traversal, and header manipulation.
• Rate Limiting & Proxy Security: Fixed-window rate limiting per client IP with CF-Connecting-IP priority. Warning: trust_proxy = true must only be enabled when the server is actually behind Cloudflare or a reverse proxy — otherwise clients can forge CF-Connecting-IP / X-Forwarded-For headers to bypass rate limiting.
• Security Headers: Enforces Content-Security-Policy, X-Content-Type-Options: nosniff, X-Frame-Options: DENY, and Referrer-Policy: no-referrer.
• Delete Semantics & Forensics: Disk-level recovery of deleted ciphertext is possible — local files are removed, not zeroed, and S3 deletes are logical. Zero-knowledge is unaffected because the decryption key never reaches the server, but "ephemeral" is not forensically guaranteed.

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API Reference

• POST /api/uploads — Initialize upload session
• PUT /api/uploads/{id}/parts/{part} — Upload part data (Local backend)
• GET /api/uploads/{id}/parts/{part}/presign — Get presigned S3 URL (S3 backend)
• POST /api/uploads/{id}/complete — Finalize upload session
• DELETE /api/uploads/{id} — Abort upload session
• GET /api/uploads/{id} — Get upload metadata
• GET /raw/{id} — Stream encrypted payload
• GET /healthz — Health check endpoint

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Testing

# Run server test suite
cargo test

# Run S3 integration tests against MinIO
TEMPDROP_TEST_S3=1 \
TEMPDROP_S3_ENDPOINT=http://127.0.0.1:9000 \
TEMPDROP_S3_BUCKET=tempdrop-test \
TEMPDROP_S3_ACCESS_KEY=minioadmin \
TEMPDROP_S3_SECRET_KEY=minioadmin \
cargo test --test s3_minio

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License

MIT