#tls #ssl #rust


MesaLink is a memory-safe and OpenSSL-compatible TLS library based on Rustls and Ring

8 releases (1 stable)

✓ Uses Rust 2018 edition

1.1.0-beta Aug 14, 2019
1.0.0 Apr 2, 2019
0.8.0 Jan 27, 2019
0.7.2 Nov 24, 2018
0.6.1 Apr 9, 2018

#111 in Network programming

1,254 stars & 48 watchers


6.5K SLoC

A memory-safe and OpenSSL-compatible TLS library

Build Status Build Status Coverage Status Documentation Status Release License

MesaLink is a memory-safe and OpenSSL-compatible TLS library. MesaLink has been in production at Baidu with >10 million monthly active users.

Visit us on our website: https://mesalink.io.

Release history

  • 1.0.0 (🎂 04-02-2019 🎂)
    • CMake support; see the updated CROSS_COMPILE.md for cross-compilation instructions
    • Windows builds (MSVC and MinGW)
    • CI/CD migrated to Azure Pipelines
    • NSIS installer for Win64 available
    • Mutex/RwLock from parking_lot
    • Session caches with hashbrown
    • Optional jemalloc memory allocator with jemallocator
    • Renovated website
  • 0.8.0 (01-25-2019)
    • 40 new OpenSSL APIs, covering BIO, EVP_PKEY, PEM and X509
    • SSL_CTX and SSL are thread-safe
    • Configurable session cache
    • SHA1 signatures discontinued
    • Tested with rust-san memory and leak sanitizers
    • Rust 2018 edition
    • Based on rustls 0.15, webpki 0.19, and *ring* 0.14
    • TLS backend for curl since 7.62.0
    • TLS backend for brpc, an industrial-grade RPC framework; see the patches directory
    • Experimental SGX Remote Attestation for Untrusted Enclaves (see SGX_README.md)
  • 0.7.2 (11-24-2018)
    • Client authentication
    • Use armv7-linux-androideabi for Android builds
  • 0.7.1 (09-05-2018)
    • SSL_CTX_load_verify_location
    • Fix duplicate floatdisf symbols

See OLD_CHANGES.md for further change history.

Feature highlights

  • Memory safety. MesaLink is impervious to bugs like Heartbleed and buffer overflows becuse it is written in Rust.
  • Cross Platform. Linux, macOS, Android, Windows; x86, x86_64, armv7, aarch64... you name it. MesaLink probably compiles for it.
  • Modern Ciphersuites. MesaLink uses the best ciphersuites including AES-GCM, Chacha20Poly1305, and elliptic-curve key exchange with perfect forward secrecy.
  • TLS 1.3. Eight years since TLS 1.2, the faster and more secure TLS standard, is now in Rustls and MesaLink.
  • Blazing Fast. X25519 key exchange, AES-NI support, no language runtime like Java/Go. MesaLink runs at full speed on your metal.
  • Flexible Configuration: MesaLink offers flexible configurations tailored to your needs. You can customize which ciphers and TLS versions are built-in.
  • Transparent Replacement. MesaLink provides OpenSSL-compatible C APIs. Want to use MesaLink in curl or Android? No problem.
  • Production Ready. Baidu uses MesaLink in production with 10M monthly active users as of 12/2018

MesaLink depends on two Rust crates: rustls and sct. With them, MesaLink provides the following features that are considered secure for most use cases:

  • TLS 1.2 and TLS 1.3
  • ECDSA and RSA server authentication
  • Forced hostname validation
  • Forward secrecy using ECDHE; with curve25519, nistp256 or nistp384 curves.
  • Safe and fast crypto primitives from BoringSSL
  • AES-128-GCM, AES-256-GCM and Chacha20-Poly1305 bulk encryption
  • Built-in Mozilla's CA root certificates

Supported ciphersuites

  • TLS13-CHACHA20-POLY1305-SHA256
  • TLS13-AES-256-GCM-SHA384
  • TLS13-AES-128-GCM_SHA256

Building instructions for Autotools

$ sudo apt-get install m4 autoconf automake libtool make gcc curl
$ curl https://sh.rustup.rs -sSf | sh

$ git clone https://github.com/mesalock-linux/mesalink.git
$ ./autogen.sh --enable-examples
$ make

Building instructions for CMake

$ sudo apt-get install cmake make gcc curl
$ curl https://sh.rustup.rs -sSf | sh

$ git clone https://github.com/mesalock-linux/mesalink.git
$ mkdir build && cd build
$ cmake ..
$ cmake --build .


MesaLink comes with two examples that demonstrate a TLS client and a TLS server. Both of them are located at examples/.

The client example connects to a remote HTTPS server and prints the server's response.

$ ./examples/client/client api.ipify.org
[+] Negotiated ciphersuite: TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256, enc_length=16, version=TLS1.2
[+] Subject name: /OU=Domain Control Validated/OU=PositiveSSL Wildcard/CN=*.ipify.org
[+] Subject alternative names:*.ipify.org ipify.org
[+] Sent 85 bytes

GET / HTTP/1.0
Host: api.ipify.org
Connection: close
Accept-Encoding: identity

HTTP/1.1 200 OK
Server: Cowboy
Connection: close
Content-Type: text/plain
Vary: Origin
Date: Thu, 09 Aug 2018 21:44:35 GMT
Content-Length: 10
Via: 1.1 vegur
[+] TLS protocol version: TLS1.2

[+] Received 177 bytes

The server example comes with a pair of certificate and private key. The certificate file is in the PEM format and contains a chain of certificates from the server's certificate to the root CA certificate. The private key file contains a PKCS8-encoded private key in the PEM format. Once the server is up and running, open and expect to see the hello message.

$ ./examples/server/server
Usage: ./examples/server/server <portnum> <cert_file> <private_key_file>
$ cd examples/server/server
$ ./server 8443 certificates private_key
[+] Listening at
[+] Negotiated ciphersuite: TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256, enc_length=16, version=TLS1.2
[+] Received:
GET / HTTP/1.1
Connection: keep-alive
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_2) AppleWebKit/537.36
(KHTML, like Gecko) Chrome/63.0.3239.84 Safari/537.36
Upgrade-Insecure-Requests: 1
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng
Accept-Encoding: gzip, deflate, br
Accept-Language: en-US,en;q=0.9

Unit tests

MesaLink uses cargo for unit tests. Simply run cargo test.

$ cargo test

BoringSSL SSL tests

BoGo is BoringSSL's protocol level test suite. We have ported BoGo for testing the functionality and compatibility of MesaLink. To run BoGo test cases, run the following:

$ cd bogo && ./runme


The MesaLink project would not have been possible without the following high-quality open source projects in the Rust community. Thanks for code and inspiration!

  • rustls: A modern TLS library in Rust, maintained by Joseph Birr-Pixton @ctz
  • sct.rs: Certificate transparency SCT verification library in rust, maintained by Joseph Birr-Pixton @ctz
  • ring: Safe, fast, small crypto using Rust, by Brian Smith @briansmith
  • webpki: WebPKI X.509 Certificate Validation in Rust, maintained by Brian Smith @briansmith
  • crypto-bench: Benchmarks for crypto libraries, maintained by Brian Smith @briansmith
  • Special thanks to Brian Smith for insights and valuable discussion


  • Yiming Jing <jingyiming@baidu.com> @kevinis

Steering Committee

  • Tao Wei
  • Yulong Zhang


MesaLink is provided under the 3-Clause BSD license. For a copy, see the LICENSE file.


~286K SLoC