contego/README.md

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## Cryptographic specifications

The initial key exchange is performed with elliptic-curve Diffie-Hellman. General data exchange is encrypted with AES-GCM. During regular communication payloads are Base64 encoded before being encrypted to prevent delimiter conflicts. SHA-256 hashes of files are compared to ensure data integrity.

## Cellular networks

Most cellular ISP's tend to block port forwarding on CGNAT level, which makes it impossible to create inbound connections to such network without a VPN. Luckily many consumer VPNs and self-hosted solutions make port forwarding a trivial task. This is the main reason why the client must fetch information about the public IP from an external service (https://ipinfo.io/ip for IPv4 and https://ipv6.icanhazip.com for IPv6). 

## Usage

Work in progress. Will be completed when the current release is finished.

```shell
cargo build --release
./target/release/contego
```