From b6df54ccbdb53c8a5ce6494e7f693c0bc454a8d9 Mon Sep 17 00:00:00 2001
From: Claas <claas@claas.dev>
Date: Tue, 24 Sep 2024 21:48:58 +0200
Subject: [PATCH] Add endpoints and extractor for TLS codec bodies

---
 Cargo.lock                        | 833 +++++++++++++++++++++++++++++-
 delivery-service/Cargo.toml       |  10 +
 delivery-service/src/extractor.rs |  45 ++
 delivery-service/src/main.rs      | 116 ++++-
 4 files changed, 997 insertions(+), 7 deletions(-)
 create mode 100644 delivery-service/src/extractor.rs

diff --git a/Cargo.lock b/Cargo.lock
index e2144fd..9903304 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2,6 +2,21 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "addr2line"
+version = "0.24.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f5fb1d8e4442bd405fdfd1dacb42792696b0cf9cb15882e5d097b742a676d375"
+dependencies = [
+ "gimli",
+]
+
+[[package]]
+name = "adler2"
+version = "2.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "512761e0bb2578dd7380c6baaa0f4ce03e84f95e960231d1dec8bf4d7d6e2627"
+
 [[package]]
 name = "aead"
 version = "0.5.2"
@@ -37,18 +52,129 @@ dependencies = [
  "subtle",
 ]
 
+[[package]]
+name = "aho-corasick"
+version = "1.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8e60d3430d3a69478ad0993f19238d2df97c507009a52b3c10addcd7f6bcb916"
+dependencies = [
+ "memchr",
+]
+
+[[package]]
+name = "async-trait"
+version = "0.1.82"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a27b8a3a6e1a44fa4c8baf1f653e4172e81486d4941f2237e20dc2d0cf4ddff1"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "autocfg"
 version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0c4b4d0bd25bd0b74681c0ad21497610ce1b7c91b1022cd21c80c6fbdd9476b0"
 
+[[package]]
+name = "axum"
+version = "0.7.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8f43644eed690f5374f1af436ecd6aea01cd201f6fbdf0178adaf6907afb2cec"
+dependencies = [
+ "async-trait",
+ "axum-core",
+ "axum-macros",
+ "base64 0.21.7",
+ "bytes",
+ "futures-util",
+ "http",
+ "http-body",
+ "http-body-util",
+ "hyper",
+ "hyper-util",
+ "itoa",
+ "matchit",
+ "memchr",
+ "mime",
+ "percent-encoding",
+ "pin-project-lite",
+ "rustversion",
+ "serde",
+ "serde_json",
+ "serde_path_to_error",
+ "serde_urlencoded",
+ "sha1",
+ "sync_wrapper 1.0.1",
+ "tokio",
+ "tokio-tungstenite",
+ "tower 0.5.1",
+ "tower-layer",
+ "tower-service",
+ "tracing",
+]
+
+[[package]]
+name = "axum-core"
+version = "0.4.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5e6b8ba012a258d63c9adfa28b9ddcf66149da6f986c5b5452e629d5ee64bf00"
+dependencies = [
+ "async-trait",
+ "bytes",
+ "futures-util",
+ "http",
+ "http-body",
+ "http-body-util",
+ "mime",
+ "pin-project-lite",
+ "rustversion",
+ "sync_wrapper 1.0.1",
+ "tower-layer",
+ "tower-service",
+ "tracing",
+]
+
+[[package]]
+name = "axum-macros"
+version = "0.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "57d123550fa8d071b7255cb0cc04dc302baa6c8c4a79f55701552684d8399bce"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "backtrace"
+version = "0.3.74"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8d82cb332cdfaed17ae235a638438ac4d4839913cc2af585c3c6746e8f8bee1a"
+dependencies = [
+ "addr2line",
+ "cfg-if",
+ "libc",
+ "miniz_oxide",
+ "object",
+ "rustc-demangle",
+ "windows-targets",
+]
+
 [[package]]
 name = "base16ct"
 version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4c7f02d4ea65f2c1853089ffd8d2787bdbc63de2f0d29dedbcf8ccdfa0ccd4cf"
 
+[[package]]
+name = "base64"
+version = "0.21.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9d297deb1925b89f2ccc13d7635fa0714f12c87adce1c75356b39ca9b7178567"
+
 [[package]]
 name = "base64"
 version = "0.22.1"
@@ -67,6 +193,12 @@ version = "1.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
 
+[[package]]
+name = "bitflags"
+version = "2.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b048fb63fd8b5923fc5aa7b340d8e156aec7ec02f0c78fa8a6ddc2613f6f71de"
+
 [[package]]
 name = "block-buffer"
 version = "0.10.4"
@@ -88,6 +220,12 @@ version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1fd0f2584146f6f2ef48085050886acf353beff7305ebd1ae69500e27c67f64b"
 
+[[package]]
+name = "bytes"
+version = "1.7.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "428d9aa8fbc0670b7b8d6030a7fadd0f86151cae55e4dbbece15f3780a3dfaf3"
+
 [[package]]
 name = "cfg-if"
 version = "1.0.0"
@@ -238,9 +376,27 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "data-encoding"
+version = "2.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e8566979429cf69b49a5c740c60791108e86440e8be149bbea4fe54d2c32d6e2"
+
 [[package]]
 name = "delivery-service"
 version = "0.1.0"
+dependencies = [
+ "axum",
+ "openmls",
+ "serde",
+ "thiserror",
+ "tls_codec",
+ "tokio",
+ "tokio-stream",
+ "tower-http",
+ "tracing",
+ "tracing-subscriber",
+]
 
 [[package]]
 name = "der"
@@ -355,13 +511,28 @@ checksum = "b768c170dc045fa587a8f948c91f9bcfb87f774930477c6215addf54317f137f"
 dependencies = [
  "futures",
  "js-sys",
- "parking_lot",
+ "parking_lot 0.11.2",
  "pin-utils",
  "wasm-bindgen",
  "wasm-bindgen-futures",
  "web-sys",
 ]
 
+[[package]]
+name = "fnv"
+version = "1.0.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3f9eec918d3f24069decb9af1554cad7c880e2da24a9afd88aca000531ab82c1"
+
+[[package]]
+name = "form_urlencoded"
+version = "1.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e13624c2627564efccf4934284bdd98cbaa14e79b0b5a141218e507b3a823456"
+dependencies = [
+ "percent-encoding",
+]
+
 [[package]]
 name = "futures"
 version = "0.3.30"
@@ -485,6 +656,12 @@ dependencies = [
  "polyval",
 ]
 
+[[package]]
+name = "gimli"
+version = "0.31.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "32085ea23f3234fc7846555e85283ba4de91e21016dc0455a16286d87a292d64"
+
 [[package]]
 name = "group"
 version = "0.13.0"
@@ -496,6 +673,12 @@ dependencies = [
  "subtle",
 ]
 
+[[package]]
+name = "hermit-abi"
+version = "0.3.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d231dfb89cfffdbc30e7fc41579ed6066ad03abda9e567ccafae602b97ec5024"
+
 [[package]]
 name = "hkdf"
 version = "0.12.4"
@@ -554,6 +737,88 @@ dependencies = [
  "x25519-dalek",
 ]
 
+[[package]]
+name = "http"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "21b9ddb458710bc376481b842f5da65cdf31522de232c1ca8146abce2a358258"
+dependencies = [
+ "bytes",
+ "fnv",
+ "itoa",
+]
+
+[[package]]
+name = "http-body"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1efedce1fb8e6913f23e0c92de8e62cd5b772a67e7b3946df930a62566c93184"
+dependencies = [
+ "bytes",
+ "http",
+]
+
+[[package]]
+name = "http-body-util"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "793429d76616a256bcb62c2a2ec2bed781c8307e797e2598c50010f2bee2544f"
+dependencies = [
+ "bytes",
+ "futures-util",
+ "http",
+ "http-body",
+ "pin-project-lite",
+]
+
+[[package]]
+name = "httparse"
+version = "1.9.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0fcc0b4a115bf80b728eb8ea024ad5bd707b615bfed49e0665b6e0f86fd082d9"
+
+[[package]]
+name = "httpdate"
+version = "1.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "df3b46402a9d5adb4c86a0cf463f42e19994e3ee891101b1841f30a545cb49a9"
+
+[[package]]
+name = "hyper"
+version = "1.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "50dfd22e0e76d0f662d429a5f80fcaf3855009297eab6a0a9f8543834744ba05"
+dependencies = [
+ "bytes",
+ "futures-channel",
+ "futures-util",
+ "http",
+ "http-body",
+ "httparse",
+ "httpdate",
+ "itoa",
+ "pin-project-lite",
+ "smallvec",
+ "tokio",
+]
+
+[[package]]
+name = "hyper-util"
+version = "0.1.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "da62f120a8a37763efb0cf8fdf264b884c7b8b9ac8660b900c8661030c00e6ba"
+dependencies = [
+ "bytes",
+ "futures-util",
+ "http",
+ "http-body",
+ "hyper",
+ "pin-project-lite",
+ "tokio",
+ "tower 0.4.13",
+ "tower-service",
+]
+
 [[package]]
 name = "inout"
 version = "0.1.3"
@@ -590,6 +855,12 @@ dependencies = [
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "lazy_static"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bbd2bcb4c963f2ddae06a2efc7e9f3591312473c50c6685e1f298068316e66fe"
+
 [[package]]
 name = "libc"
 version = "0.2.159"
@@ -612,11 +883,26 @@ version = "0.4.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a7a70ba024b9dc04c27ea2f0c0548feb474ec5c54bba33a7f72f873a39d07b24"
 
+[[package]]
+name = "matchers"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8263075bb86c5a1b1427b5ae862e8889656f126e9f77c484496e8b47cf5c5558"
+dependencies = [
+ "regex-automata 0.1.10",
+]
+
+[[package]]
+name = "matchit"
+version = "0.7.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0e7465ac9959cc2b1404e8e2367b43684a6d13790fe23056cc8c6c5a6b7bcb94"
+
 [[package]]
 name = "meal"
 version = "0.1.0"
 dependencies = [
- "base64",
+ "base64 0.22.1",
  "console_error_panic_hook",
  "openmls",
  "openmls_basic_credential",
@@ -633,6 +919,52 @@ version = "2.7.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "78ca9ab1a0babb1e7d5695e3530886289c18cf2f87ec19a575a0abdce112e3a3"
 
+[[package]]
+name = "mime"
+version = "0.3.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6877bb514081ee2a7ff5ef9de3281f14a4dd4bceac4c09388074a6b5df8a139a"
+
+[[package]]
+name = "miniz_oxide"
+version = "0.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e2d80299ef12ff69b16a84bb182e3b9df68b5a91574d3d4fa6e41b65deec4df1"
+dependencies = [
+ "adler2",
+]
+
+[[package]]
+name = "mio"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "80e04d1dcff3aae0704555fe5fee3bcfaf3d1fdf8a7e521d5b9d2b42acb52cec"
+dependencies = [
+ "hermit-abi",
+ "libc",
+ "wasi",
+ "windows-sys",
+]
+
+[[package]]
+name = "nu-ansi-term"
+version = "0.46.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "77a8165726e8236064dbb45459242600304b42a5ea24ee2948e18e023bf7ba84"
+dependencies = [
+ "overload",
+ "winapi",
+]
+
+[[package]]
+name = "object"
+version = "0.36.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "084f1a5821ac4c651660a94a7153d27ac9d8a53736203f58b31945ded098070a"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "once_cell"
 version = "1.19.0"
@@ -723,6 +1055,12 @@ dependencies = [
  "tls_codec",
 ]
 
+[[package]]
+name = "overload"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b15813163c1d831bf4a13c3610c05c0d03b39feb07f7e09fa234dac9b15aaf39"
+
 [[package]]
 name = "p256"
 version = "0.13.2"
@@ -753,7 +1091,17 @@ checksum = "7d17b78036a60663b797adeaee46f5c9dfebb86948d1255007a1d6be0271ff99"
 dependencies = [
  "instant",
  "lock_api",
- "parking_lot_core",
+ "parking_lot_core 0.8.6",
+]
+
+[[package]]
+name = "parking_lot"
+version = "0.12.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f1bf18183cf54e8d6059647fc3063646a1801cf30896933ec2311622cc4b9a27"
+dependencies = [
+ "lock_api",
+ "parking_lot_core 0.9.10",
 ]
 
 [[package]]
@@ -765,11 +1113,24 @@ dependencies = [
  "cfg-if",
  "instant",
  "libc",
- "redox_syscall",
+ "redox_syscall 0.2.16",
  "smallvec",
  "winapi",
 ]
 
+[[package]]
+name = "parking_lot_core"
+version = "0.9.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1e401f977ab385c9e4e3ab30627d6f26d00e2c73eef317493c4ec6d468726cf8"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "redox_syscall 0.5.5",
+ "smallvec",
+ "windows-targets",
+]
+
 [[package]]
 name = "pem-rfc7468"
 version = "0.7.0"
@@ -779,6 +1140,32 @@ dependencies = [
  "base64ct",
 ]
 
+[[package]]
+name = "percent-encoding"
+version = "2.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e3148f5046208a5d56bcfc03053e3ca6334e51da8dfb19b6cdc8b306fae3283e"
+
+[[package]]
+name = "pin-project"
+version = "1.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b6bf43b791c5b9e34c3d182969b4abb522f9343702850a2e57f460d00d09b4b3"
+dependencies = [
+ "pin-project-internal",
+]
+
+[[package]]
+name = "pin-project-internal"
+version = "1.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2f38a4412a78282e09a2cf38d195ea5420d15ba0602cb375210efbc877243965"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "pin-project-lite"
 version = "0.2.14"
@@ -916,9 +1303,62 @@ version = "0.2.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "fb5a58c1855b4b6819d59012155603f0b22ad30cad752600aadfcb695265519a"
 dependencies = [
- "bitflags",
+ "bitflags 1.3.2",
+]
+
+[[package]]
+name = "redox_syscall"
+version = "0.5.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "62871f2d65009c0256aed1b9cfeeb8ac272833c404e13d53d400cd0dad7a2ac0"
+dependencies = [
+ "bitflags 2.6.0",
+]
+
+[[package]]
+name = "regex"
+version = "1.10.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4219d74c6b67a3654a9fbebc4b419e22126d13d2f3c4a07ee0cb61ff79a79619"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-automata 0.4.7",
+ "regex-syntax 0.8.4",
+]
+
+[[package]]
+name = "regex-automata"
+version = "0.1.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6c230d73fb8d8c1b9c0b3135c5142a8acee3a0558fb8db5cf1cb65f8d7862132"
+dependencies = [
+ "regex-syntax 0.6.29",
+]
+
+[[package]]
+name = "regex-automata"
+version = "0.4.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "38caf58cc5ef2fed281f89292ef23f6365465ed9a41b7a7754eb4e26496c92df"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax 0.8.4",
 ]
 
+[[package]]
+name = "regex-syntax"
+version = "0.6.29"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f162c6dd7b008981e4d40210aca20b4bd0f9b60ca9271061b07f78537722f2e1"
+
+[[package]]
+name = "regex-syntax"
+version = "0.8.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7a66a03ae7c801facd77a29370b4faec201768915ac14a721ba36f20bc9c209b"
+
 [[package]]
 name = "rfc6979"
 version = "0.4.0"
@@ -929,6 +1369,12 @@ dependencies = [
  "subtle",
 ]
 
+[[package]]
+name = "rustc-demangle"
+version = "0.1.24"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "719b953e2095829ee67db738b3bfa9fa368c94900df327b3f07fe6e794d2fe1f"
+
 [[package]]
 name = "rustc_version"
 version = "0.4.1"
@@ -938,6 +1384,12 @@ dependencies = [
  "semver",
 ]
 
+[[package]]
+name = "rustversion"
+version = "1.0.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "955d28af4278de8121b7ebeb796b6a45735dc01436d898801014aced2773a3d6"
+
 [[package]]
 name = "ryu"
 version = "1.0.18"
@@ -1002,6 +1454,39 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "serde_path_to_error"
+version = "0.1.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "af99884400da37c88f5e9146b7f1fd0fbcae8f6eec4e9da38b67d05486f814a6"
+dependencies = [
+ "itoa",
+ "serde",
+]
+
+[[package]]
+name = "serde_urlencoded"
+version = "0.7.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d3491c14715ca2294c4d6a88f15e84739788c1d030eed8c110436aafdaa2f3fd"
+dependencies = [
+ "form_urlencoded",
+ "itoa",
+ "ryu",
+ "serde",
+]
+
+[[package]]
+name = "sha1"
+version = "0.10.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e3bf829a2d51ab4a5ddf1352d8470c140cadc8301b2ae1789db023f01cedd6ba"
+dependencies = [
+ "cfg-if",
+ "cpufeatures",
+ "digest",
+]
+
 [[package]]
 name = "sha2"
 version = "0.10.8"
@@ -1013,6 +1498,24 @@ dependencies = [
  "digest",
 ]
 
+[[package]]
+name = "sharded-slab"
+version = "0.1.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f40ca3c46823713e0d4209592e8d6e826aa57e928f09752619fc696c499637f6"
+dependencies = [
+ "lazy_static",
+]
+
+[[package]]
+name = "signal-hook-registry"
+version = "1.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a9e9e0b4211b72e7b8b6e85c807d36c212bdb33ea8587f7569562a84df5465b1"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "signature"
 version = "2.2.0"
@@ -1038,6 +1541,16 @@ version = "1.13.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3c5e1a9a646d36c3599cd173a41282daf47c44583ad367b8e6837255952e5c67"
 
+[[package]]
+name = "socket2"
+version = "0.5.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ce305eb0b4296696835b71df73eb912e0f1ffd2556a501fcede6e0c50349191c"
+dependencies = [
+ "libc",
+ "windows-sys",
+]
+
 [[package]]
 name = "spki"
 version = "0.7.3"
@@ -1065,6 +1578,18 @@ dependencies = [
  "unicode-ident",
 ]
 
+[[package]]
+name = "sync_wrapper"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2047c6ded9c721764247e62cd3b03c09ffc529b2ba5b10ec482ae507a4a70160"
+
+[[package]]
+name = "sync_wrapper"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a7065abeca94b6a8a577f9bd45aa0867a2238b74e8eb67cf10d492bc39351394"
+
 [[package]]
 name = "thiserror"
 version = "1.0.64"
@@ -1085,6 +1610,16 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "thread_local"
+version = "1.1.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b9ef9bad013ada3808854ceac7b46812a6465ba368859a37e2100283d2d719c"
+dependencies = [
+ "cfg-if",
+ "once_cell",
+]
+
 [[package]]
 name = "tls_codec"
 version = "0.4.1"
@@ -1107,6 +1642,209 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "tokio"
+version = "1.40.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e2b070231665d27ad9ec9b8df639893f46727666c6767db40317fbe920a5d998"
+dependencies = [
+ "backtrace",
+ "bytes",
+ "libc",
+ "mio",
+ "parking_lot 0.12.3",
+ "pin-project-lite",
+ "signal-hook-registry",
+ "socket2",
+ "tokio-macros",
+ "windows-sys",
+]
+
+[[package]]
+name = "tokio-macros"
+version = "2.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "693d596312e88961bc67d7f1f97af8a70227d9f90c31bba5806eec004978d752"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "tokio-stream"
+version = "0.1.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4f4e6ce100d0eb49a2734f8c0812bcd324cf357d21810932c5df6b96ef2b86f1"
+dependencies = [
+ "futures-core",
+ "pin-project-lite",
+ "tokio",
+ "tokio-util",
+]
+
+[[package]]
+name = "tokio-tungstenite"
+version = "0.23.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c6989540ced10490aaf14e6bad2e3d33728a2813310a0c71d1574304c49631cd"
+dependencies = [
+ "futures-util",
+ "log",
+ "tokio",
+ "tungstenite",
+]
+
+[[package]]
+name = "tokio-util"
+version = "0.7.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "61e7c3654c13bcd040d4a03abee2c75b1d14a37b423cf5a813ceae1cc903ec6a"
+dependencies = [
+ "bytes",
+ "futures-core",
+ "futures-sink",
+ "pin-project-lite",
+ "tokio",
+]
+
+[[package]]
+name = "tower"
+version = "0.4.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b8fa9be0de6cf49e536ce1851f987bd21a43b771b09473c3549a6c853db37c1c"
+dependencies = [
+ "futures-core",
+ "futures-util",
+ "pin-project",
+ "pin-project-lite",
+ "tokio",
+ "tower-layer",
+ "tower-service",
+]
+
+[[package]]
+name = "tower"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2873938d487c3cfb9aed7546dc9f2711d867c9f90c46b889989a2cb84eba6b4f"
+dependencies = [
+ "futures-core",
+ "futures-util",
+ "pin-project-lite",
+ "sync_wrapper 0.1.2",
+ "tokio",
+ "tower-layer",
+ "tower-service",
+ "tracing",
+]
+
+[[package]]
+name = "tower-http"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8437150ab6bbc8c5f0f519e3d5ed4aa883a83dd4cdd3d1b21f9482936046cb97"
+dependencies = [
+ "bitflags 2.6.0",
+ "bytes",
+ "http",
+ "pin-project-lite",
+ "tower-layer",
+ "tower-service",
+]
+
+[[package]]
+name = "tower-layer"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "121c2a6cda46980bb0fcd1647ffaf6cd3fc79a013de288782836f6df9c48780e"
+
+[[package]]
+name = "tower-service"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8df9b6e13f2d32c91b9bd719c00d1958837bc7dec474d94952798cc8e69eeec3"
+
+[[package]]
+name = "tracing"
+version = "0.1.40"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c3523ab5a71916ccf420eebdf5521fcef02141234bbc0b8a49f2fdc4544364ef"
+dependencies = [
+ "log",
+ "pin-project-lite",
+ "tracing-attributes",
+ "tracing-core",
+]
+
+[[package]]
+name = "tracing-attributes"
+version = "0.1.27"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "34704c8d6ebcbc939824180af020566b01a7c01f80641264eba0999f6c2b6be7"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "tracing-core"
+version = "0.1.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c06d3da6113f116aaee68e4d601191614c9053067f9ab7f6edbcb161237daa54"
+dependencies = [
+ "once_cell",
+ "valuable",
+]
+
+[[package]]
+name = "tracing-log"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ee855f1f400bd0e5c02d150ae5de3840039a3f54b025156404e34c23c03f47c3"
+dependencies = [
+ "log",
+ "once_cell",
+ "tracing-core",
+]
+
+[[package]]
+name = "tracing-subscriber"
+version = "0.3.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ad0f048c97dbd9faa9b7df56362b8ebcaa52adb06b498c050d2f4e32f90a7a8b"
+dependencies = [
+ "matchers",
+ "nu-ansi-term",
+ "once_cell",
+ "regex",
+ "sharded-slab",
+ "smallvec",
+ "thread_local",
+ "tracing",
+ "tracing-core",
+ "tracing-log",
+]
+
+[[package]]
+name = "tungstenite"
+version = "0.23.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6e2e2ce1e47ed2994fd43b04c8f618008d4cabdd5ee34027cf14f9d918edd9c8"
+dependencies = [
+ "byteorder",
+ "bytes",
+ "data-encoding",
+ "http",
+ "httparse",
+ "log",
+ "rand",
+ "sha1",
+ "thiserror",
+ "utf-8",
+]
+
 [[package]]
 name = "typenum"
 version = "1.17.0"
@@ -1129,6 +1867,18 @@ dependencies = [
  "subtle",
 ]
 
+[[package]]
+name = "utf-8"
+version = "0.7.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "09cc8ee72d2a9becf2f2febe0205bbed8fc6615b7cb429ad062dc7b7ddd036a9"
+
+[[package]]
+name = "valuable"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "830b7e5d4d90034032940e4ace0d9a9a057e7a45cd94e6c007832e39edb82f6d"
+
 [[package]]
 name = "version_check"
 version = "0.9.5"
@@ -1240,6 +1990,79 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
 
+[[package]]
+name = "windows-sys"
+version = "0.52.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "282be5f36a8ce781fad8c8ae18fa3f9beff57ec1b52cb3de0789201425d9a33d"
+dependencies = [
+ "windows-targets",
+]
+
+[[package]]
+name = "windows-targets"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9b724f72796e036ab90c1021d4780d4d3d648aca59e491e6b98e725b84e99973"
+dependencies = [
+ "windows_aarch64_gnullvm",
+ "windows_aarch64_msvc",
+ "windows_i686_gnu",
+ "windows_i686_gnullvm",
+ "windows_i686_msvc",
+ "windows_x86_64_gnu",
+ "windows_x86_64_gnullvm",
+ "windows_x86_64_msvc",
+]
+
+[[package]]
+name = "windows_aarch64_gnullvm"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "32a4622180e7a0ec044bb555404c800bc9fd9ec262ec147edd5989ccd0c02cd3"
+
+[[package]]
+name = "windows_aarch64_msvc"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "09ec2a7bb152e2252b53fa7803150007879548bc709c039df7627cabbd05d469"
+
+[[package]]
+name = "windows_i686_gnu"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8e9b5ad5ab802e97eb8e295ac6720e509ee4c243f69d781394014ebfe8bbfa0b"
+
+[[package]]
+name = "windows_i686_gnullvm"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0eee52d38c090b3caa76c563b86c3a4bd71ef1a819287c19d586d7334ae8ed66"
+
+[[package]]
+name = "windows_i686_msvc"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "240948bc05c5e7c6dabba28bf89d89ffce3e303022809e73deaefe4f6ec56c66"
+
+[[package]]
+name = "windows_x86_64_gnu"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "147a5c80aabfbf0c7d901cb5895d1de30ef2907eb21fbbab29ca94c5b08b1a78"
+
+[[package]]
+name = "windows_x86_64_gnullvm"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "24d5b23dc417412679681396f2b49f3de8c1473deb516bd34410872eff51ed0d"
+
+[[package]]
+name = "windows_x86_64_msvc"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "589f6da84c646204747d1270a2a5661ea66ed1cced2631d546fdfb155959f9ec"
+
 [[package]]
 name = "x25519-dalek"
 version = "2.0.1"
diff --git a/delivery-service/Cargo.toml b/delivery-service/Cargo.toml
index 55e84f7..1222051 100644
--- a/delivery-service/Cargo.toml
+++ b/delivery-service/Cargo.toml
@@ -4,3 +4,13 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
+axum = { version = "0.7.6", features = ["macros", "ws"] }
+openmls = "0.6.0"
+serde = { version = "1.0.210", features = ["derive", "rc"] }
+thiserror = "1.0.64"
+tls_codec = "0.4.1"
+tokio = { version = "1.40.0", features = ["full"] }
+tokio-stream = { version = "0.1.16", features = ["sync"] }
+tower-http = { version = "0.6.1", features = ["cors"] }
+tracing = "0.1.40"
+tracing-subscriber = { version = "0.3.18", features = ["env-filter"] }
diff --git a/delivery-service/src/extractor.rs b/delivery-service/src/extractor.rs
new file mode 100644
index 0000000..3653c52
--- /dev/null
+++ b/delivery-service/src/extractor.rs
@@ -0,0 +1,45 @@
+use axum::{
+    async_trait,
+    body::Bytes,
+    extract::{rejection::BytesRejection, FromRequest, Request},
+    http::StatusCode,
+    response::IntoResponse,
+};
+use thiserror::Error;
+
+pub(crate) struct TlsCodec<T: tls_codec::DeserializeBytes>(pub(crate) T);
+
+#[derive(Error, Debug)]
+pub(crate) enum TlsCodecRejection {
+    #[error("Error reading bytes from body")]
+    BytesError(#[from] BytesRejection),
+    #[error("Error deserializing TLS codec body")]
+    DeserializationError(#[from] tls_codec::Error),
+}
+
+impl IntoResponse for TlsCodecRejection {
+    fn into_response(self) -> axum::response::Response {
+        match self {
+            TlsCodecRejection::BytesError(error) => error.into_response(),
+            TlsCodecRejection::DeserializationError(error) => {
+                tracing::trace!("Error during TLS codec deserialization: {:?}", error);
+                StatusCode::BAD_REQUEST.into_response()
+            }
+        }
+    }
+}
+
+#[async_trait]
+impl<S, T> FromRequest<S> for TlsCodec<T>
+where
+    S: Send + Sync,
+    T: tls_codec::DeserializeBytes,
+{
+    type Rejection = TlsCodecRejection;
+
+    async fn from_request(request: Request, state: &S) -> Result<Self, Self::Rejection> {
+        let bytes = Bytes::from_request(request, state).await?;
+        let value = T::tls_deserialize_exact_bytes(&bytes)?;
+        Ok(Self(value))
+    }
+}
diff --git a/delivery-service/src/main.rs b/delivery-service/src/main.rs
index e7a11a9..00aa068 100644
--- a/delivery-service/src/main.rs
+++ b/delivery-service/src/main.rs
@@ -1,3 +1,115 @@
-fn main() {
-    println!("Hello, world!");
+use std::{collections::HashMap, convert::Infallible, sync::Arc, time::Duration};
+
+use axum::{
+    extract::{Path, State},
+    http::{HeaderValue, Method, StatusCode},
+    response::{
+        sse::{Event, KeepAlive},
+        IntoResponse, Sse,
+    },
+    routing::{get, post},
+    Router,
+};
+use extractor::TlsCodec;
+use openmls::prelude::MlsMessageIn;
+use tokio::sync::{watch, Mutex};
+use tokio_stream::{wrappers::WatchStream, StreamExt};
+use tower_http::cors::CorsLayer;
+use tracing_subscriber::{layer::SubscriberExt, util::SubscriberInitExt};
+
+mod extractor;
+
+#[derive(Clone, Default)]
+struct AppState {
+    channels: Arc<Mutex<HashMap<Arc<str>, watch::Sender<Message>>>>,
+}
+
+#[tokio::main]
+async fn main() {
+    // To debug axum extractor rejections see https://docs.rs/axum/latest/axum/extract/index.html#logging-rejections
+    tracing_subscriber::registry()
+        .with(
+            tracing_subscriber::EnvFilter::try_from_default_env().unwrap_or_else(|_| {
+                format!("{}=debug,tower_http=debug", env!("CARGO_CRATE_NAME")).into()
+            }),
+        )
+        .with(tracing_subscriber::fmt::layer())
+        .init();
+
+    tracing::info!("Starting");
+
+    let mut app = Router::new()
+        .route("/messages/:to", post(create_message))
+        .route("/messages", get(subscribe_messages));
+
+    // Not looking nice, but functional to have CORS only in development
+    #[cfg(debug_assertions)]
+    {
+        app = app.layer(
+            CorsLayer::new()
+                .allow_origin("http://localhost:5173".parse::<HeaderValue>().unwrap())
+                .allow_methods([Method::GET]),
+        );
+    }
+
+    let app = app.with_state(Default::default());
+
+    let listener = tokio::net::TcpListener::bind("0.0.0.0:3000").await.unwrap();
+
+    tracing::debug!("listening on {}", listener.local_addr().unwrap());
+    axum::serve(listener, app).await.unwrap();
+}
+
+/// This endpoint receives messages sent by clients to be delivered to other clients
+#[axum::debug_handler]
+async fn create_message(
+    State(state): State<AppState>,
+    Path(to): Path<Arc<str>>,
+    TlsCodec(message): TlsCodec<MlsMessageIn>,
+) -> impl IntoResponse {
+    let channels = state.channels.lock().await;
+    let Some(sender) = channels.get(to.as_ref()) else {
+        return StatusCode::BAD_REQUEST;
+    };
+
+    if let Err(error) = sender.send(Message) {
+        tracing::error!("Error sending message {:?}", error);
+    }
+
+    StatusCode::CREATED
+}
+
+/// Clients use this endpoint to make themselves available for receiving messages
+async fn register(State(state): State<AppState>) {}
+#[derive(Clone)]
+struct Message;
+
+/// Handles requests for listening to server sent events (SSE) that are used to send incoming messages from the server to the client
+async fn subscribe_messages(
+    State(state): State<AppState>,
+    Path(client_id): Path<Arc<str>>,
+) -> Sse<impl tokio_stream::Stream<Item = Result<Event, Infallible>>> {
+    //TODO add cryptographic client authentication to avoid session hijacking
+    //TODO (continued) (even though the hijacker can't read the messages most likely, they can analyze traffic meta data for that client)
+
+    let (sender, receiver) = watch::channel(Message);
+    // Register sender for this id
+    let previous_sender = state.channels.lock().await.insert(client_id, sender);
+    if let Some(previous_sender) = previous_sender {
+        //TODO think about if this is valid
+        tracing::warn!("Replacing previous subscriber for client");
+        // This should close the SSE stream for the other client that used the same id
+        //TODO test assumption
+        drop(previous_sender);
+    }
+
+    let stream = WatchStream::new(receiver).map(|_value| Ok(Event::default()));
+
+    let keep_alive = KeepAlive::new()
+        //TODO check for adequate interval time
+        .interval(Duration::from_secs(1))
+        //TODO think of something a bit more clever
+        .text("keep-alive-text");
+
+    Sse::new(stream).keep_alive(keep_alive)
 }
-- 
2.51.2