The chatmail core library implements low-level network and encryption protocols, integrated by many chat bots and higher level applications, allowing to securely participate in the globally scaled e-mail server network. We provide reproducibly-built deltachat-rpc-server static binaries that offer a stdio-based high-level JSON-RPC API for instant messaging purposes.

The following protocols are handled without requiring API users to know much about them:

• secure TLS setup with DNS caching and shadowsocks/proxy support

• robust SMTP and IMAP handling

• safe and interoperable MIME parsing and MIME building.

• security-audited end-to-end encryption with rPGP and Autocrypt and SecureJoin protocols

• ephemeral Peer-to-Peer networking using Iroh for multi-device setup and webxdc realtime data.

• a simulation- and real-world tested P2P group membership protocol without requiring server state.

Installing Rust and Cargo

To download and install the official compiler for the Rust programming language, and the Cargo package manager, run the command in your user environment:

$ curl https://sh.rustup.rs -sSf | sh

On Windows, you may need to also install Perl to be able to compile deltachat-core.

Using the CLI client

Compile and run the command line utility, using cargo:

$ cargo run --locked -p deltachat-repl -- ~/profile-db

where ~/profile-db is the database file. The utility will create it if it does not exist.

Optionally, install deltachat-repl binary with

$ cargo install --locked --path deltachat-repl/

and run as

$ deltachat-repl ~/profile-db

Configure your account (if not already configured):

Chatmail is awaiting your commands.
> set addr your@email.org
> set mail_pw yourpassword
> configure

Connect to your mail server (if already configured):

> connect

Export your public key to a vCard file:

> make-vcard my.vcard 1

Create contacts by address or vCard file:

> addcontact yourfriends@email.org
> import-vcard key-contact.vcard

List contacts:

> listcontacts
Contact#Contact#11: key-contact@email.org <key-contact@email.org>
Contact#Contact#Self: Me √ <your@email.org>
2 key contacts.
Contact#Contact#10: yourfriends@email.org <yourfriends@email.org>
1 address contacts.

Create a chat with your friend and send a message:

> createchat 10
Single#Chat#12 created successfully.
> chat 12
Selecting chat Chat#12
Single#Chat#12: yourfriends@email.org [yourfriends@email.org] Icon: profile-db-blobs/4138c52e5bc1c576cda7dd44d088c07.png
0 messages.
81.252µs to create this list, 123.625µs to mark all messages as noticed.
> send hi

List messages when inside a chat:

> chat

For more commands type:

> help

Installing libdeltachat system wide

$ git clone https://github.com/chatmail/core.git
$ cd deltachat-core-rust
$ cmake -B build . -DCMAKE_INSTALL_PREFIX=/usr
$ cmake --build build
$ sudo cmake --install build

Development

# run tests
$ cargo test --all
# build c-ffi
$ cargo build -p deltachat_ffi --release

Debugging environment variables

• DCC_MIME_DEBUG: if set outgoing and incoming message will be printed

• RUST_LOG=async_imap=trace,async_smtp=trace: enable IMAP and SMTP tracing in addition to info messages.

Expensive tests

Some tests are expensive and marked with #[ignore], to run these use the --ignored argument to the test binary (not to cargo itself):

$ cargo test -- --ignored

Fuzzing

Install cargo-bolero with

$ cargo install cargo-bolero

Run fuzzing tests with

$ cd fuzz
$ cargo bolero test fuzz_mailparse -s NONE

Corpus is created at fuzz/fuzz_targets/corpus, you can add initial inputs there. For fuzz_mailparse target corpus can be populated with ../test-data/message/*.eml.

Features

• vendored: When using Openssl for TLS, this bundles a vendored version.

Update Provider Data

To add the updates from the provider-db to the core, check line REV= inside ./scripts/update-provider-database.sh and then run the script.

Language bindings and frontend projects

Language bindings are available for:

• C [📂 source | 📚 docs]
  • -> libdeltachat is going to be deprecated and only exists because Android, iOS and Ubuntu Touch are still using it. If you build a new project, then please use the jsonrpc api instead.
• JS: [📂 source | 📦 npm | 📚 docs]
• Python [📂 source | 📦 pypi | 📚 docs]
• Go [📂 source]
• Java and Swift (contained in the Android/iOS repos)

The following "frontend" projects make use of the Rust-library or its language bindings:

• Android
• iOS
• Desktop
• Pidgin
• Telepathy
• Ubuntu Touch
• several Bots