From 08328c95fe7cc4e35dff5c5faecc8f32ca6f69ec Mon Sep 17 00:00:00 2001
From: Revertron <r@revertron.com>
Date: Sun, 5 Sep 2021 19:05:30 +0200
Subject: [PATCH] Added DNS-over-HTTPS support for forwarded queries.

---
 Cargo.lock               | 842 ++++++++++++++++++++++++++++++++++++++-
 Cargo.toml               |   3 +
 alfis.toml               |   7 +-
 src/blockchain/filter.rs |   2 +-
 src/dns/client.rs        | 142 ++++++-
 src/dns/context.rs       |  21 +-
 src/dns/resolve.rs       |  14 +-
 src/dns_utils.rs         |   3 +-
 src/main.rs              |   2 +
 src/settings.rs          |   7 +
 10 files changed, 1005 insertions(+), 38 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index a8c59ec..4a24193 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -65,6 +65,17 @@ dependencies = [
  "opaque-debug",
 ]
 
+[[package]]
+name = "ahash"
+version = "0.7.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "43bb833f0bf979d8475d38fbf09ed3b8a55e1885fe93ad3f93239fc6a4f17b98"
+dependencies = [
+ "getrandom 0.2.2",
+ "once_cell",
+ "version_check",
+]
+
 [[package]]
 name = "alfis"
 version = "0.6.6"
@@ -77,11 +88,13 @@ dependencies = [
  "chrono",
  "derive_more",
  "digest",
+ "dnsclient",
  "ecies-ed25519",
  "ed25519-dalek",
  "getopts",
  "lazy_static",
  "log",
+ "lru",
  "mio",
  "num-bigint",
  "num-traits",
@@ -101,13 +114,149 @@ dependencies = [
  "thread-priority",
  "tinyfiledialogs",
  "toml",
+ "ureq",
  "uuid",
  "web-view",
- "winapi",
+ "winapi 0.3.9",
  "winres",
  "x25519-dalek",
 ]
 
+[[package]]
+name = "anyhow"
+version = "1.0.43"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "28ae2b3dec75a406790005a200b1bd89785afc02517a00ca99ecfe093ee9e6cf"
+
+[[package]]
+name = "async-channel"
+version = "1.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2114d64672151c0c5eaa5e131ec84a74f06e1e559830dabba01ca30605d66319"
+dependencies = [
+ "concurrent-queue",
+ "event-listener",
+ "futures-core",
+]
+
+[[package]]
+name = "async-executor"
+version = "1.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "871f9bb5e0a22eeb7e8cf16641feb87c9dc67032ccf8ff49e772eb9941d3a965"
+dependencies = [
+ "async-task",
+ "concurrent-queue",
+ "fastrand",
+ "futures-lite",
+ "once_cell",
+ "slab",
+]
+
+[[package]]
+name = "async-global-executor"
+version = "2.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9586ec52317f36de58453159d48351bc244bc24ced3effc1fce22f3d48664af6"
+dependencies = [
+ "async-channel",
+ "async-executor",
+ "async-io",
+ "async-mutex",
+ "blocking",
+ "futures-lite",
+ "num_cpus",
+ "once_cell",
+]
+
+[[package]]
+name = "async-io"
+version = "1.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a811e6a479f2439f0c04038796b5cfb3d2ad56c230e0f2d3f7b04d68cfee607b"
+dependencies = [
+ "concurrent-queue",
+ "futures-lite",
+ "libc",
+ "log",
+ "once_cell",
+ "parking",
+ "polling",
+ "slab",
+ "socket2",
+ "waker-fn",
+ "winapi 0.3.9",
+]
+
+[[package]]
+name = "async-lock"
+version = "2.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6a8ea61bf9947a1007c5cada31e647dbc77b103c679858150003ba697ea798b"
+dependencies = [
+ "event-listener",
+]
+
+[[package]]
+name = "async-mutex"
+version = "1.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "479db852db25d9dbf6204e6cb6253698f175c15726470f78af0d918e99d6156e"
+dependencies = [
+ "event-listener",
+]
+
+[[package]]
+name = "async-process"
+version = "1.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b21b63ab5a0db0369deb913540af2892750e42d949faacc7a61495ac418a1692"
+dependencies = [
+ "async-io",
+ "blocking",
+ "cfg-if 1.0.0",
+ "event-listener",
+ "futures-lite",
+ "libc",
+ "once_cell",
+ "signal-hook",
+ "winapi 0.3.9",
+]
+
+[[package]]
+name = "async-std"
+version = "1.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f8056f1455169ab86dd47b47391e4ab0cbd25410a70e9fe675544f49bafaf952"
+dependencies = [
+ "async-channel",
+ "async-global-executor",
+ "async-io",
+ "async-lock",
+ "async-process",
+ "crossbeam-utils",
+ "futures-channel",
+ "futures-core",
+ "futures-io",
+ "futures-lite",
+ "gloo-timers",
+ "kv-log-macro",
+ "log",
+ "memchr",
+ "num_cpus",
+ "once_cell",
+ "pin-project-lite",
+ "pin-utils",
+ "slab",
+ "wasm-bindgen-futures",
+]
+
+[[package]]
+name = "async-task"
+version = "4.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e91831deabf0d6d7ec49552e489aed63b7456a7a3c46cff62adad428110b0af0"
+
 [[package]]
 name = "atk-sys"
 version = "0.10.0"
@@ -120,12 +269,43 @@ dependencies = [
  "system-deps",
 ]
 
+[[package]]
+name = "atomic-waker"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "065374052e7df7ee4047b1160cca5e1467a12351a40b3da123c870ba0b8eda2a"
+
 [[package]]
 name = "autocfg"
 version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cdb031dd78e28731d87d56cc8ffef4a8f36ca26c38fe2de700543e627f8a464a"
 
+[[package]]
+name = "backtrace"
+version = "0.1.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "150ae7828afa7afb6d474f909d64072d21de1f3365b6e8ad8029bf7b1c6350a0"
+dependencies = [
+ "backtrace-sys",
+ "cfg-if 0.1.10",
+ "dbghelp-sys",
+ "debug-builders",
+ "kernel32-sys",
+ "libc",
+ "winapi 0.2.8",
+]
+
+[[package]]
+name = "backtrace-sys"
+version = "0.1.37"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "18fbebbe1c9d1f383a9cc7e8ccdb471b91c8d024ee9c2ca5b5346121fe8b4399"
+dependencies = [
+ "cc",
+ "libc",
+]
+
 [[package]]
 name = "base64"
 version = "0.13.0"
@@ -141,6 +321,12 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "bitflags"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "aad18937a628ec6abcd26d1489012cc0e18c21798210f491af69ded9b881106d"
+
 [[package]]
 name = "bitflags"
 version = "1.2.1"
@@ -177,18 +363,44 @@ dependencies = [
  "generic-array",
 ]
 
+[[package]]
+name = "blocking"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c5e170dbede1f740736619b776d7251cb1b9095c435c34d8ca9f57fcd2f335e9"
+dependencies = [
+ "async-channel",
+ "async-task",
+ "atomic-waker",
+ "fastrand",
+ "futures-lite",
+ "once_cell",
+]
+
 [[package]]
 name = "boxfnonce"
 version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5988cb1d626264ac94100be357308f29ff7cbdd3b36bda27f450a4ee3f713426"
 
+[[package]]
+name = "bumpalo"
+version = "3.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9c59e7af012c713f529e7a3ee57ce9b31ddd858d4b512923602f74608b009631"
+
 [[package]]
 name = "byteorder"
 version = "1.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "14c189c53d098945499cdfa7ecc63567cf3886b3332b312a5b4585d8d3a6a610"
 
+[[package]]
+name = "cache-padded"
+version = "1.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "631ae5198c9be5e753e5cc215e1bd73c2b466a3565173db433f52bb9d3e66dba"
+
 [[package]]
 name = "cairo-sys-rs"
 version = "0.10.0"
@@ -205,6 +417,12 @@ version = "1.0.67"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e3c69b077ad434294d3ce9f1f6143a2a4b89a8a2d54ef813d85003a4fd1137fd"
 
+[[package]]
+name = "cfg-if"
+version = "0.1.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4785bdd1c96b2a846b2bd7cc02e86b6b3dbf14e7e53446c4f54c92a361040822"
+
 [[package]]
 name = "cfg-if"
 version = "1.0.0"
@@ -217,7 +435,7 @@ version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f8c5d87765c99be3d2cb08d11a3c14820ecaf2c7ad45d301c533103d2d8a146c"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
  "cipher 0.3.0",
  "cpufeatures 0.2.1",
  "zeroize",
@@ -236,6 +454,18 @@ dependencies = [
  "zeroize",
 ]
 
+[[package]]
+name = "chomp"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9f74ad218e66339b11fd23f693fb8f1d621e80ba6ac218297be26073365d163d"
+dependencies = [
+ "bitflags 0.7.0",
+ "conv",
+ "debugtrace",
+ "either",
+]
+
 [[package]]
 name = "chrono"
 version = "0.4.19"
@@ -247,9 +477,15 @@ dependencies = [
  "num-traits",
  "serde",
  "time",
- "winapi",
+ "winapi 0.3.9",
 ]
 
+[[package]]
+name = "chunked_transfer"
+version = "1.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fff857943da45f546682664a79488be82e69e43c1a7a2307679ab9afb3a66d2e"
+
 [[package]]
 name = "cipher"
 version = "0.2.5"
@@ -268,6 +504,24 @@ dependencies = [
  "generic-array",
 ]
 
+[[package]]
+name = "concurrent-queue"
+version = "1.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "30ed07550be01594c6026cff2a1d7fe9c8f683caa798e12b68694ac9e88286a3"
+dependencies = [
+ "cache-padded",
+]
+
+[[package]]
+name = "conv"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "78ff10625fd0ac447827aa30ea8b861fead473bb60aeb73af6c1c58caf0d1299"
+dependencies = [
+ "custom_derive",
+]
+
 [[package]]
 name = "convert_case"
 version = "0.4.0"
@@ -298,6 +552,16 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "dcb25d077389e53838a8158c8e99174c5a9d902dee4904320db714f3c653ffba"
 
+[[package]]
+name = "crossbeam-utils"
+version = "0.8.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d82cfc11ce7f2c3faef78d8a684447b40d503d9681acebed6cb728d45940c4db"
+dependencies = [
+ "cfg-if 1.0.0",
+ "lazy_static",
+]
+
 [[package]]
 name = "crypto-mac"
 version = "0.8.0"
@@ -318,6 +582,16 @@ dependencies = [
  "subtle",
 ]
 
+[[package]]
+name = "ctor"
+version = "0.1.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5e98e2ad1a782e33928b96fc3948e7c355e5af34ba4de7670fe8bac2a3b2006d"
+dependencies = [
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "ctr"
 version = "0.6.0"
@@ -340,6 +614,37 @@ dependencies = [
  "zeroize",
 ]
 
+[[package]]
+name = "custom_derive"
+version = "0.1.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ef8ae57c4978a2acd8b869ce6b9ca1dfe817bff704c220209fdef2c0b75a01b9"
+
+[[package]]
+name = "dbghelp-sys"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "97590ba53bcb8ac28279161ca943a924d1fd4a8fb3fa63302591647c4fc5b850"
+dependencies = [
+ "winapi 0.2.8",
+ "winapi-build",
+]
+
+[[package]]
+name = "debug-builders"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0f5d8e3d14cabcb2a8a59d7147289173c6ada77a0bc526f6b85078f941c0cf12"
+
+[[package]]
+name = "debugtrace"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "62e432bd83c5d70317f6ebd8a50ed4afb32907c64d6e2e1e65e339b06dc553f3"
+dependencies = [
+ "backtrace",
+]
+
 [[package]]
 name = "derive_more"
 version = "0.99.16"
@@ -362,6 +667,32 @@ dependencies = [
  "generic-array",
 ]
 
+[[package]]
+name = "dnsclient"
+version = "0.1.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0ca5429947886eabb8da7268aa9d61ba4348347417b04452310bf3b5b5258ac7"
+dependencies = [
+ "async-std",
+ "dnssector",
+ "rand 0.8.4",
+]
+
+[[package]]
+name = "dnssector"
+version = "0.2.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ef40cef9c349123274f45efc0021dcd1bd4b5b35226eafe4b84a9d8a2a6deeeb"
+dependencies = [
+ "anyhow",
+ "byteorder",
+ "chomp",
+ "hex",
+ "libc",
+ "rand 0.8.4",
+ "thiserror",
+]
+
 [[package]]
 name = "ecies-ed25519"
 version = "0.5.1"
@@ -402,6 +733,73 @@ dependencies = [
  "zeroize",
 ]
 
+[[package]]
+name = "either"
+version = "0.1.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a39bffec1e2015c5d8a6773cb0cf48d0d758c842398f624c34969071f5499ea7"
+
+[[package]]
+name = "event-listener"
+version = "2.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f7531096570974c3a9dcf9e4b8e1cede1ec26cf5046219fb3b9d897503b9be59"
+
+[[package]]
+name = "fastrand"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b394ed3d285a429378d3b384b9eb1285267e7df4b166df24b7a6939a04dc392e"
+dependencies = [
+ "instant",
+]
+
+[[package]]
+name = "form_urlencoded"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5fc25a87fa4fd2094bffb06925852034d90a17f0d1e05197d4956d3555752191"
+dependencies = [
+ "matches",
+ "percent-encoding",
+]
+
+[[package]]
+name = "futures-channel"
+version = "0.3.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5da6ba8c3bb3c165d3c7319fc1cc8304facf1fb8db99c5de877183c08a273888"
+dependencies = [
+ "futures-core",
+]
+
+[[package]]
+name = "futures-core"
+version = "0.3.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "88d1c26957f23603395cd326b0ffe64124b818f4449552f960d815cfba83a53d"
+
+[[package]]
+name = "futures-io"
+version = "0.3.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "522de2a0fe3e380f1bc577ba0474108faf3f6b18321dbf60b3b9c39a75073377"
+
+[[package]]
+name = "futures-lite"
+version = "1.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7694489acd39452c77daa48516b894c153f192c3578d5a839b62c58099fcbf48"
+dependencies = [
+ "fastrand",
+ "futures-core",
+ "futures-io",
+ "memchr",
+ "parking",
+ "pin-project-lite",
+ "waker-fn",
+]
+
 [[package]]
 name = "gdk-pixbuf-sys"
 version = "0.10.0"
@@ -457,7 +855,7 @@ version = "0.1.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8fc3cb4d91f53b50155bdcfd23f6a4c39ae1969c2ae85982b135750cccaf5fce"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
  "libc",
  "wasi 0.9.0+wasi-snapshot-preview1",
 ]
@@ -468,7 +866,7 @@ version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c9495705279e7140bf035dde1f6e750c162df8b625267cd52cc44e0b156732c8"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
  "libc",
  "wasi 0.10.2+wasi-snapshot-preview1",
 ]
@@ -493,7 +891,7 @@ dependencies = [
  "gobject-sys",
  "libc",
  "system-deps",
- "winapi",
+ "winapi 0.3.9",
 ]
 
 [[package]]
@@ -506,6 +904,19 @@ dependencies = [
  "system-deps",
 ]
 
+[[package]]
+name = "gloo-timers"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "47204a46aaff920a1ea58b11d03dec6f704287d27561724a4631e450654a891f"
+dependencies = [
+ "futures-channel",
+ "futures-core",
+ "js-sys",
+ "wasm-bindgen",
+ "web-sys",
+]
+
 [[package]]
 name = "gobject-sys"
 version = "0.10.0"
@@ -541,6 +952,15 @@ version = "1.7.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "62aca2aba2d62b4a7f5b33f3712cb1b0692779a56fb510499d5c0aa594daeaf3"
 
+[[package]]
+name = "hashbrown"
+version = "0.11.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ab5ef0d4909ef3724cc8cce6ccc8572c5c817592e9285f5464f8e86f8bd3726e"
+dependencies = [
+ "ahash",
+]
+
 [[package]]
 name = "heck"
 version = "0.3.2"
@@ -585,6 +1005,26 @@ dependencies = [
  "digest",
 ]
 
+[[package]]
+name = "idna"
+version = "0.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "418a0a6fab821475f634efe3ccc45c013f742efe03d853e8d3355d5cb850ecf8"
+dependencies = [
+ "matches",
+ "unicode-bidi",
+ "unicode-normalization",
+]
+
+[[package]]
+name = "instant"
+version = "0.1.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bee0328b1209d157ef001c94dd85b4f8f64139adb0eac2659f4b08382b2f474d"
+dependencies = [
+ "cfg-if 1.0.0",
+]
+
 [[package]]
 name = "itoa"
 version = "0.4.7"
@@ -600,6 +1040,34 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "js-sys"
+version = "0.3.53"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e4bf49d50e2961077d9c99f4b7997d770a1114f087c3c2e0069b36c13fc2979d"
+dependencies = [
+ "wasm-bindgen",
+]
+
+[[package]]
+name = "kernel32-sys"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7507624b29483431c0ba2d82aece8ca6cdba9382bff4ddd0f7490560c056098d"
+dependencies = [
+ "winapi 0.2.8",
+ "winapi-build",
+]
+
+[[package]]
+name = "kv-log-macro"
+version = "1.0.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0de8b303297635ad57c9f5059fd9cee7a47f8e8daa09df0fcd07dd39fb22977f"
+dependencies = [
+ "log",
+]
+
 [[package]]
 name = "lazy_static"
 version = "1.4.0"
@@ -618,9 +1086,31 @@ version = "0.4.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "51b9bbe6c47d51fc3e1a9b945965946b4c44142ab8792c50835a980d362c2710"
 dependencies = [
- "cfg-if",
+ "cfg-if 1.0.0",
+ "value-bag",
 ]
 
+[[package]]
+name = "lru"
+version = "0.6.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7ea2d928b485416e8908cff2d97d621db22b27f7b3b6729e438bcf42c671ba91"
+dependencies = [
+ "hashbrown",
+]
+
+[[package]]
+name = "matches"
+version = "0.1.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a3e378b66a060d48947b590737b30a1be76706c8dd7b8ba0f2fe3989c68a853f"
+
+[[package]]
+name = "memchr"
+version = "2.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "308cc39be01b73d0d18f82a0e7b2a3df85245f84af96fdddc5d202d27e47b86a"
+
 [[package]]
 name = "mio"
 version = "0.7.13"
@@ -631,7 +1121,7 @@ dependencies = [
  "log",
  "miow",
  "ntapi",
- "winapi",
+ "winapi 0.3.9",
 ]
 
 [[package]]
@@ -640,7 +1130,7 @@ version = "0.3.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b9f1c5b025cda876f66ef43a113f91ebc9f4ccef34843000e0adf6ebbab84e21"
 dependencies = [
- "winapi",
+ "winapi 0.3.9",
 ]
 
 [[package]]
@@ -649,7 +1139,7 @@ version = "0.3.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3f6bb902e437b6d86e03cce10a7e2af662292c5dfef23b65899ea3ac9354ad44"
 dependencies = [
- "winapi",
+ "winapi 0.3.9",
 ]
 
 [[package]]
@@ -692,6 +1182,12 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "once_cell"
+version = "1.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "692fcb63b64b1758029e0a96ee63e049ce8c5948587f2f7208df04625e5f6b56"
+
 [[package]]
 name = "opaque-debug"
 version = "0.3.0"
@@ -705,7 +1201,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b46b233de7d83bc167fe43ae2dda3b5b84e80e09cceba581e4decb958a4896bf"
 dependencies = [
  "pathdiff",
- "winapi",
+ "winapi 0.3.9",
 ]
 
 [[package]]
@@ -720,12 +1216,24 @@ dependencies = [
  "system-deps",
 ]
 
+[[package]]
+name = "parking"
+version = "2.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "427c3892f9e783d91cc128285287e70a59e206ca452770ece88a76f7a3eddd72"
+
 [[package]]
 name = "pathdiff"
 version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "877630b3de15c0b64cc52f659345724fbf6bdad9bd9566699fc53688f3c34a34"
 
+[[package]]
+name = "percent-encoding"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d4fd5641d01c8f18a23da7b6fe29298ff4b55afcccdf78973b24cf3175fee32e"
+
 [[package]]
 name = "pest"
 version = "2.1.3"
@@ -735,12 +1243,37 @@ dependencies = [
  "ucd-trie",
 ]
 
+[[package]]
+name = "pin-project-lite"
+version = "0.2.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8d31d11c69a6b52a174b42bdc0c30e5e11670f90788b2c471c31c1d17d449443"
+
+[[package]]
+name = "pin-utils"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b870d8c151b6f2fb93e84a13146138f05d02ed11c7e7c54f8826aaaf7c9f184"
+
 [[package]]
 name = "pkg-config"
 version = "0.3.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3831453b3449ceb48b6d9c7ad7c96d5ea673e9b470a1dc578c2ce6521230884c"
 
+[[package]]
+name = "polling"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "92341d779fa34ea8437ef4d82d440d5e1ce3f3ff7f824aa64424cd481f9a1f25"
+dependencies = [
+ "cfg-if 1.0.0",
+ "libc",
+ "log",
+ "wepoll-ffi",
+ "winapi 0.3.9",
+]
+
 [[package]]
 name = "poly1305"
 version = "0.7.0"
@@ -868,6 +1401,21 @@ dependencies = [
  "rand_core 0.6.2",
 ]
 
+[[package]]
+name = "ring"
+version = "0.16.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3053cf52e236a3ed746dfc745aa9cacf1b791d846bdaf412f60a8d7d6e17c8fc"
+dependencies = [
+ "cc",
+ "libc",
+ "once_cell",
+ "spin",
+ "untrusted",
+ "web-sys",
+ "winapi 0.3.9",
+]
+
 [[package]]
 name = "rustc_version"
 version = "0.3.3"
@@ -877,12 +1425,35 @@ dependencies = [
  "semver",
 ]
 
+[[package]]
+name = "rustls"
+version = "0.19.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "35edb675feee39aec9c99fa5ff985081995a06d594114ae14cbe797ad7b7a6d7"
+dependencies = [
+ "base64",
+ "log",
+ "ring",
+ "sct",
+ "webpki",
+]
+
 [[package]]
 name = "ryu"
 version = "1.0.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "71d301d4193d031abdd79ff7e3dd721168a9572ef3fe51a1517aba235bd8f86e"
 
+[[package]]
+name = "sct"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b362b83898e0e69f38515b82ee15aa80636befe47c3b6d3d89a911e78fc228ce"
+dependencies = [
+ "ring",
+ "untrusted",
+]
+
 [[package]]
 name = "semver"
 version = "0.11.0"
@@ -958,12 +1529,31 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9204c41a1597a8c5af23c82d1c921cb01ec0a4c59e07a9c7306062829a3903f3"
 dependencies = [
  "block-buffer",
- "cfg-if",
+ "cfg-if 1.0.0",
  "cpufeatures 0.2.1",
  "digest",
  "opaque-debug",
 ]
 
+[[package]]
+name = "signal-hook"
+version = "0.3.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9c98891d737e271a2954825ef19e46bd16bdb98e2746f2eec4f7a4ef7946efd1"
+dependencies = [
+ "libc",
+ "signal-hook-registry",
+]
+
+[[package]]
+name = "signal-hook-registry"
+version = "1.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e51e73328dc4ac0c7ccbda3a494dfa03df1de2f46018127f60c693f2648455b0"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "signature"
 version = "1.3.1"
@@ -981,13 +1571,29 @@ dependencies = [
  "termcolor",
 ]
 
+[[package]]
+name = "slab"
+version = "0.4.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c307a32c1c5c437f38c7fd45d753050587732ba8628319fbdf12a7e289ccc590"
+
+[[package]]
+name = "socket2"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "765f090f0e423d2b55843402a07915add955e7d60657db13707a159727326cad"
+dependencies = [
+ "libc",
+ "winapi 0.3.9",
+]
+
 [[package]]
 name = "soup-sys"
 version = "0.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c3c7adf08565630bbb71f955f11f8a68464817ded2703a3549747c235b58a13e"
 dependencies = [
- "bitflags",
+ "bitflags 1.2.1",
  "gio-sys",
  "glib-sys",
  "gobject-sys",
@@ -996,6 +1602,12 @@ dependencies = [
  "system-deps",
 ]
 
+[[package]]
+name = "spin"
+version = "0.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6e63cff320ae2c57904679ba7cb63280a3dc4613885beafb148ee7bf9aa9042d"
+
 [[package]]
 name = "sqlite"
 version = "0.26.0"
@@ -1124,7 +1736,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cbb8681124ddad2b07e677d7a99f564c9edbd289cc53cdc0010fd110cb4818ec"
 dependencies = [
  "libc",
- "winapi",
+ "winapi 0.3.9",
 ]
 
 [[package]]
@@ -1134,7 +1746,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ca8a50ef2360fbd1eeb0ecd46795a87a19024eb4b53c5dc916ca1fd95fe62438"
 dependencies = [
  "libc",
- "winapi",
+ "winapi 0.3.9",
 ]
 
 [[package]]
@@ -1147,6 +1759,21 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "tinyvec"
+version = "1.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "848a1e1181b9f6753b5e96a092749e29b11d19ede67dfbbd6c7dc7e0f49b5338"
+dependencies = [
+ "tinyvec_macros",
+]
+
+[[package]]
+name = "tinyvec_macros"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cda74da7e1a664f795bb1f8a87ec406fb89a02522cf6e50620d016add6dbbf5c"
+
 [[package]]
 name = "toml"
 version = "0.5.8"
@@ -1168,6 +1795,21 @@ version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "56dee185309b50d1f11bfedef0fe6d036842e3fb77413abef29f8f8d1c5d4c1c"
 
+[[package]]
+name = "unicode-bidi"
+version = "0.3.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "246f4c42e67e7a4e3c6106ff716a5d067d4132a642840b242e357e468a2a0085"
+
+[[package]]
+name = "unicode-normalization"
+version = "0.1.19"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d54590932941a9e9266f0832deed84ebe1bf2e4c9e4a3554d393d18f5e854bf9"
+dependencies = [
+ "tinyvec",
+]
+
 [[package]]
 name = "unicode-segmentation"
 version = "1.7.1"
@@ -1196,6 +1838,40 @@ dependencies = [
  "subtle",
 ]
 
+[[package]]
+name = "untrusted"
+version = "0.7.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a156c684c91ea7d62626509bce3cb4e1d9ed5c4d978f7b4352658f96a4c26b4a"
+
+[[package]]
+name = "ureq"
+version = "2.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3131cd6cb18488da91da1d10ed31e966f453c06b65bf010d35638456976a3fd7"
+dependencies = [
+ "base64",
+ "chunked_transfer",
+ "log",
+ "once_cell",
+ "rustls",
+ "url",
+ "webpki",
+ "webpki-roots",
+]
+
+[[package]]
+name = "url"
+version = "2.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a507c383b2d33b5fc35d1861e77e6b383d158b2da5e14fe51b83dfedf6fd578c"
+dependencies = [
+ "form_urlencoded",
+ "idna",
+ "matches",
+ "percent-encoding",
+]
+
 [[package]]
 name = "urlencoding"
 version = "1.1.1"
@@ -1212,6 +1888,16 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "value-bag"
+version = "1.0.0-alpha.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dd320e1520f94261153e96f7534476ad869c14022aee1e59af7c778075d840ae"
+dependencies = [
+ "ctor",
+ "version_check",
+]
+
 [[package]]
 name = "version-compare"
 version = "0.0.10"
@@ -1224,6 +1910,12 @@ version = "0.9.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5fecdca9a5291cc2b8dcf7dc02453fee791a280f3743cb0905f8822ae463b3fe"
 
+[[package]]
+name = "waker-fn"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9d5b2c62b4012a3e1eca5a7e077d13b3bf498c4073e33ccd58626607748ceeca"
+
 [[package]]
 name = "wasi"
 version = "0.9.0+wasi-snapshot-preview1"
@@ -1236,6 +1928,82 @@ version = "0.10.2+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "fd6fbd9a79829dd1ad0cc20627bf1ed606756a7f77edff7b66b7064f9cb327c6"
 
+[[package]]
+name = "wasm-bindgen"
+version = "0.2.76"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8ce9b1b516211d33767048e5d47fa2a381ed8b76fc48d2ce4aa39877f9f183e0"
+dependencies = [
+ "cfg-if 1.0.0",
+ "wasm-bindgen-macro",
+]
+
+[[package]]
+name = "wasm-bindgen-backend"
+version = "0.2.76"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cfe8dc78e2326ba5f845f4b5bf548401604fa20b1dd1d365fb73b6c1d6364041"
+dependencies = [
+ "bumpalo",
+ "lazy_static",
+ "log",
+ "proc-macro2",
+ "quote",
+ "syn",
+ "wasm-bindgen-shared",
+]
+
+[[package]]
+name = "wasm-bindgen-futures"
+version = "0.4.26"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "95fded345a6559c2cfee778d562300c581f7d4ff3edb9b0d230d69800d213972"
+dependencies = [
+ "cfg-if 1.0.0",
+ "js-sys",
+ "wasm-bindgen",
+ "web-sys",
+]
+
+[[package]]
+name = "wasm-bindgen-macro"
+version = "0.2.76"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "44468aa53335841d9d6b6c023eaab07c0cd4bddbcfdee3e2bb1e8d2cb8069fef"
+dependencies = [
+ "quote",
+ "wasm-bindgen-macro-support",
+]
+
+[[package]]
+name = "wasm-bindgen-macro-support"
+version = "0.2.76"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0195807922713af1e67dc66132c7328206ed9766af3858164fb583eedc25fbad"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+ "wasm-bindgen-backend",
+ "wasm-bindgen-shared",
+]
+
+[[package]]
+name = "wasm-bindgen-shared"
+version = "0.2.76"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "acdb075a845574a1fa5f09fd77e43f7747599301ea3417a9fbffdeedfc1f4a29"
+
+[[package]]
+name = "web-sys"
+version = "0.3.53"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "224b2f6b67919060055ef1a67807367c2066ed520c3862cc013d26cf893a783c"
+dependencies = [
+ "js-sys",
+ "wasm-bindgen",
+]
+
 [[package]]
 name = "web-view"
 version = "0.7.3"
@@ -1255,7 +2023,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "389e5138c85a0d111b9bda05b59efa8562315e1d657d72451410e12c858f0619"
 dependencies = [
  "atk-sys",
- "bitflags",
+ "bitflags 1.2.1",
  "cairo-sys-rs",
  "gdk-pixbuf-sys",
  "gdk-sys",
@@ -1270,6 +2038,25 @@ dependencies = [
  "soup-sys",
 ]
 
+[[package]]
+name = "webpki"
+version = "0.21.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b8e38c0608262c46d4a56202ebabdeb094cef7e560ca7a226c6bf055188aa4ea"
+dependencies = [
+ "ring",
+ "untrusted",
+]
+
+[[package]]
+name = "webpki-roots"
+version = "0.21.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "aabe153544e473b775453675851ecc86863d2a81d786d741f6b76778f2a48940"
+dependencies = [
+ "webpki",
+]
+
 [[package]]
 name = "webview-sys"
 version = "0.6.2"
@@ -1288,6 +2075,21 @@ dependencies = [
  "webkit2gtk-sys",
 ]
 
+[[package]]
+name = "wepoll-ffi"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d743fdedc5c64377b5fc2bc036b01c7fd642205a0d96356034ae3404d49eb7fb"
+dependencies = [
+ "cc",
+]
+
+[[package]]
+name = "winapi"
+version = "0.2.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "167dc9d6949a9b857f3451275e911c3f44255842c1f7a76f33c55103a909087a"
+
 [[package]]
 name = "winapi"
 version = "0.3.9"
@@ -1298,6 +2100,12 @@ dependencies = [
  "winapi-x86_64-pc-windows-gnu",
 ]
 
+[[package]]
+name = "winapi-build"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2d315eee3b34aca4797b2da6b13ed88266e6d612562a0c46390af8299fc699bc"
+
 [[package]]
 name = "winapi-i686-pc-windows-gnu"
 version = "0.4.0"
@@ -1310,7 +2118,7 @@ version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "70ec6ce85bb158151cae5e5c87f95a8e97d2c0c4b001223f33a334e3ce5de178"
 dependencies = [
- "winapi",
+ "winapi 0.3.9",
 ]
 
 [[package]]
diff --git a/Cargo.toml b/Cargo.toml
index 9f12325..a0c6a1c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -38,6 +38,9 @@ rand-old = { package = "rand", version = "0.7.0" } # For ed25519-dalek
 sqlite = "0.26.0"
 uuid = { version = "0.8.2", features = ["serde", "v4"] }
 mio = { version = "0.7.13", features = ["os-poll", "net"] }
+ureq = "2.2"
+dnsclient = "0.1"
+lru = "0.6"
 derive_more = "0.99.16"
 lazy_static = "1.4.0"
 
diff --git a/alfis.toml b/alfis.toml
index 267e9de..1a9c021 100644
--- a/alfis.toml
+++ b/alfis.toml
@@ -23,9 +23,12 @@ listen = "127.0.0.1:53"
 # How many threads to spawn by DNS server
 threads = 50
 # AdGuard DNS servers to filter ads and trackers
-forwarders = ["94.140.14.14:53", "94.140.15.15:53"]
+forwarders = ["https://dns.adguard.com/dns-query", "94.140.14.14:53", "94.140.15.15:53"]
 # Cloudflare servers
-#forwarders = ["1.1.1.1:53", "1.0.0.1:53"]
+#forwarders = ["https://cloudflare-dns.com/dns-query", "1.1.1.1:53", "1.0.0.1:53"]
+
+# Bootstrap DNS-servers to resolve domains of DoH providers
+bootstraps = ["9.9.9.9:53", "94.140.14.140:53"]
 
 # Hosts file support (resolve local names or block ads)
 #hosts = ["system", "adblock.txt"]
diff --git a/src/blockchain/filter.rs b/src/blockchain/filter.rs
index d11b3a6..37b56cb 100644
--- a/src/blockchain/filter.rs
+++ b/src/blockchain/filter.rs
@@ -44,7 +44,7 @@ impl DnsFilter for BlockchainFilter {
                 subdomain = String::from(parts[2]);
             }
         }
-        trace!("Searching record type '{:?}', name '{}' for domain '{}'", &qtype, &subdomain, &search);
+        //trace!("Searching record type '{:?}', name '{}' for domain '{}'", &qtype, &subdomain, &search);
 
         let data = self.context.lock().unwrap().chain.get_domain_info(&search);
         let zone = parts[0].to_owned();
diff --git a/src/dns/client.rs b/src/dns/client.rs
index 7ce7520..e705f4c 100644
--- a/src/dns/client.rs
+++ b/src/dns/client.rs
@@ -1,20 +1,25 @@
 //! client for sending DNS queries to other servers
 
-use std::io::Write;
+use std::io::{Write, Read};
 use std::marker::{Send, Sync};
-use std::net::{SocketAddr, TcpStream, ToSocketAddrs, UdpSocket};
+use std::net::{SocketAddr, TcpStream, ToSocketAddrs, UdpSocket, IpAddr};
 use std::sync::atomic::{AtomicUsize, Ordering};
 use std::sync::mpsc::{channel, Sender};
-use std::sync::{Arc, Mutex};
+use std::sync::{Arc, Mutex, RwLock};
 use std::thread::{sleep, Builder};
 use std::time::Duration as SleepDuration;
 
 use chrono::*;
 use derive_more::{Display, Error, From};
 
-use crate::dns::buffer::{BytePacketBuffer, PacketBuffer, StreamPacketBuffer};
+#[allow(unused_imports)]
+use log::{debug, error, info, trace, warn};
+
+use crate::dns::buffer::{BytePacketBuffer, PacketBuffer, StreamPacketBuffer, VectorPacketBuffer};
 use crate::dns::netutil::{read_packet_length, write_packet_length};
 use crate::dns::protocol::{DnsPacket, DnsQuestion, QueryType};
+use dnsclient::UpstreamServer;
+use lru::LruCache;
 
 #[derive(Debug, Display, From, Error)]
 pub enum ClientError {
@@ -38,7 +43,7 @@ pub trait DnsClient {
 /// The UDP client
 ///
 /// This includes a fair bit of synchronization due to the stateless nature of UDP.
-/// When many queries are sent in parallell, the response packets can come back
+/// When many queries are sent in parallel, the response packets can come back
 /// in any order. For that reason, we fire off replies on the sending thread, but
 /// handle replies on a single thread. A channel is created for every response,
 /// and the caller will block on the channel until the a response is received.
@@ -337,11 +342,136 @@ impl DnsClient for DnsNetworkClient {
             return Ok(packet);
         }
 
-        println!("Truncated response - resending as TCP");
+        info!("Truncated response - resending as TCP");
         self.send_tcp_query(qname, qtype, server, recursive)
     }
 }
 
+pub struct HttpsDnsClient {
+    agent: ureq::Agent,
+    /// Counter for assigning packet ids
+    seq: AtomicUsize,
+}
+
+impl HttpsDnsClient {
+    pub fn new(bootstraps: Vec<String>) -> Self {
+        let client_name = format!("ALFIS/{}", env!("CARGO_PKG_VERSION"));
+        let servers = bootstraps
+            .iter()
+            .filter_map(|addr| addr.parse().ok())
+            .map(|addr: SocketAddr| UpstreamServer::new(addr.clone()))
+            .collect::<Vec<_>>();
+        trace!("Using bootstraps: {:?}", &servers);
+
+        let dns_client = dnsclient::sync::DNSClient::new(servers);
+        let cache: LruCache<String, Vec<SocketAddr>> = LruCache::new(10);
+        let cache = RwLock::new(cache);
+
+        let agent = ureq::AgentBuilder::new()
+            .user_agent(&client_name)
+            .timeout(std::time::Duration::from_secs(3))
+            .resolver(move |addr: &str| {
+                let addr = match addr.find(":") {
+                    Some(index) => addr[0..index].to_string(),
+                    None => addr.to_string()
+                };
+                trace!("Resolving {}", addr);
+                if let Some(addrs) = cache.write().unwrap().get(&addr) {
+                    trace!("Found bootstrap ip in cache");
+                    return Ok(addrs.clone());
+                }
+
+                let mut result: Vec<IpAddr> = Vec::new();
+                if let Ok(addrs) = dns_client.query_a(&addr) {
+                    result.extend(addrs.into_iter().map(|ip| IpAddr::V4(ip)))
+                }
+                if let Ok(addrs) = dns_client.query_aaaa(&addr) {
+                    result.extend(addrs.into_iter().map(|ip| IpAddr::V6(ip)));
+                }
+
+                let addrs = result
+                    .into_iter()
+                    .map(|ip| SocketAddr::new(ip, 443))
+                    .collect::<Vec<_>>();
+                trace!("Resolved addresses: {:?}", &addrs);
+                cache.write().unwrap().put(addr, addrs.clone());
+                Ok(addrs)
+            })
+            .build();
+        Self { agent, seq: AtomicUsize::new(1) }
+    }
+}
+
+impl DnsClient for HttpsDnsClient {
+    fn get_sent_count(&self) -> usize {
+        // No statistics for now
+        0
+    }
+
+    fn get_failed_count(&self) -> usize {
+        // No statistics for now
+        0
+    }
+
+    fn run(&self) -> Result<()> {
+        debug!("Started DoH client");
+        Ok(())
+    }
+
+    fn send_query(&self, qname: &str, qtype: QueryType, doh_url: &str, recursive: bool) -> Result<DnsPacket> {
+        // Create DnsPacket
+        let mut packet = DnsPacket::new();
+        packet.header.id = self.seq.fetch_add(1, Ordering::SeqCst) as u16;
+        if packet.header.id + 1 == 0xFFFF {
+            let _ = self.seq.compare_exchange(0xFFFF, 0, Ordering::SeqCst, Ordering::SeqCst);
+        }
+
+        packet.header.questions = 1;
+        packet.header.recursion_desired = recursive;
+        packet.questions.push(DnsQuestion::new(String::from(qname), qtype));
+
+        let mut req_buffer = VectorPacketBuffer::new();
+        packet.write(&mut req_buffer, 512).expect("Preparing DnsPacket failed!");
+
+        let response = self.agent
+            .post(doh_url)
+            .set("Content-Type", "application/dns-message")
+            .send_bytes(&req_buffer.buffer.as_slice());
+
+        match response {
+            Ok(response) => {
+                match response.status() {
+                    200 => {
+                        match response.header("Content-Length") {
+                            None => warn!("No 'Content-Length' header in DoH response!"),
+                            Some(str) => {
+                                match str.parse::<usize>() {
+                                    Ok(size) => {
+                                        let mut bytes: Vec<u8> = Vec::with_capacity(size);
+                                        response.into_reader()
+                                            .take(4096)
+                                            .read_to_end(&mut bytes)?;
+                                        let mut buffer = VectorPacketBuffer::new();
+                                        buffer.buffer.extend_from_slice(&bytes.as_slice());
+                                        if let Ok(packet) = DnsPacket::from_buffer(&mut buffer) {
+                                            return Ok(packet);
+                                        }
+                                        warn!("Error parsing DoH result!");
+                                    }
+                                    Err(e) => warn!("Error parsing 'Content-Length' in DoH response! {}", e)
+                                }
+                            }
+                        }
+                    }
+                    _ => warn!("Error getting DoH response")
+                }
+            }
+            Err(e) => warn!("DoH error: {}", &e.to_string())
+        }
+        Err(ClientError::LookupFailed)
+    }
+}
+
 #[cfg(test)]
 pub mod tests {
     use super::*;
diff --git a/src/dns/context.rs b/src/dns/context.rs
index 2fce375..5550494 100644
--- a/src/dns/context.rs
+++ b/src/dns/context.rs
@@ -7,7 +7,7 @@ use derive_more::{Display, Error, From};
 
 use crate::dns::authority::Authority;
 use crate::dns::cache::SynchronizedCache;
-use crate::dns::client::{DnsClient, DnsNetworkClient};
+use crate::dns::client::{DnsClient, DnsNetworkClient, HttpsDnsClient};
 use crate::dns::filter::DnsFilter;
 use crate::dns::resolve::{DnsResolver, ForwardingDnsResolver, RecursiveDnsResolver};
 
@@ -44,7 +44,8 @@ pub struct ServerContext {
     pub authority: Authority,
     pub cache: SynchronizedCache,
     pub filters: Vec<Box<dyn DnsFilter + Sync + Send>>,
-    pub client: Box<dyn DnsClient + Sync + Send>,
+    pub old_client: Box<dyn DnsClient + Sync + Send>,
+    pub doh_client: Box<dyn DnsClient + Sync + Send>,
     pub dns_listen: String,
     pub api_port: u16,
     pub resolve_strategy: ResolveStrategy,
@@ -58,18 +59,19 @@ pub struct ServerContext {
 
 impl Default for ServerContext {
     fn default() -> Self {
-        ServerContext::new()
+        ServerContext::new(String::from("0.0.0.0:53"), Vec::new())
     }
 }
 
 impl ServerContext {
-    pub fn new() -> ServerContext {
+    pub fn new(dns_listen: String, bootstraps: Vec<String>) -> ServerContext {
         ServerContext {
             authority: Authority::new(),
             cache: SynchronizedCache::new(),
             filters: Vec::new(),
-            client: Box::new(DnsNetworkClient::new(10000 + (rand::random::<u16>() % 20000))),
-            dns_listen: String::from("0.0.0.0:53"),
+            old_client: Box::new(DnsNetworkClient::new(10000 + (rand::random::<u16>() % 20000))),
+            doh_client: Box::new(HttpsDnsClient::new(bootstraps)),
+            dns_listen,
             api_port: 5380,
             resolve_strategy: ResolveStrategy::Recursive,
             allow_recursive: true,
@@ -83,7 +85,9 @@ impl ServerContext {
 
     pub fn initialize(&mut self) -> Result<()> {
         // Start UDP client thread
-        self.client.run()?;
+        self.old_client.run()?;
+        // Start DoH client
+        self.doh_client.run()?;
 
         // Load authority data
         self.authority.load()?;
@@ -117,7 +121,8 @@ pub mod tests {
             authority: Authority::new(),
             cache: SynchronizedCache::new(),
             filters: Vec::new(),
-            client: Box::new(DnsStubClient::new(callback)),
+            old_client: Box::new(DnsStubClient::new(callback)),
+            doh_client: Box::new(HttpsDnsClient::new()),
             dns_listen: String::from("0.0.0.0:53"),
             api_port: 5380,
             resolve_strategy: ResolveStrategy::Recursive,
diff --git a/src/dns/resolve.rs b/src/dns/resolve.rs
index efbae04..4444560 100644
--- a/src/dns/resolve.rs
+++ b/src/dns/resolve.rs
@@ -87,7 +87,13 @@ impl DnsResolver for ForwardingDnsResolver {
         let mut random = rand::thread_rng();
         let upstream = self.upstreams.iter().choose(&mut random).unwrap();
         let result = match self.context.cache.lookup(qname, qtype) {
-            None => self.context.client.send_query(qname, qtype, upstream, true)?,
+            None => {
+                if is_url(upstream) {
+                    self.context.doh_client.send_query(qname, qtype, upstream, true)?
+                } else {
+                    self.context.old_client.send_query(qname, qtype, upstream, true)?
+                }
+            },
             Some(packet) => packet
         };
 
@@ -150,7 +156,7 @@ impl DnsResolver for RecursiveDnsResolver {
             let ns_copy = ns.clone();
 
             let server = format!("{}:{}", ns_copy.as_str(), 53);
-            let response = self.context.client.send_query(qname, qtype.clone(), &server, false)?;
+            let response = self.context.old_client.send_query(qname, qtype.clone(), &server, false)?;
 
             // If we've got an actual answer, we're done!
             if !response.answers.is_empty() && response.header.rescode == ResultCode::NOERROR {
@@ -198,6 +204,10 @@ impl DnsResolver for RecursiveDnsResolver {
     }
 }
 
+fn is_url(url: &str) -> bool {
+    url.starts_with("https://")
+}
+
 #[cfg(test)]
 mod tests {
 
diff --git a/src/dns_utils.rs b/src/dns_utils.rs
index aed9b7a..4067bb2 100644
--- a/src/dns_utils.rs
+++ b/src/dns_utils.rs
@@ -31,9 +31,8 @@ pub fn start_dns_server(context: &Arc<Mutex<Context>>, settings: &Settings) {
 
 /// Creates DNS-context with all needed settings
 fn create_server_context(context: Arc<Mutex<Context>>, settings: &Settings) -> Arc<ServerContext> {
-    let mut server_context = ServerContext::new();
+    let mut server_context = ServerContext::new(settings.dns.listen.clone(), settings.dns.bootstraps.clone());
     server_context.allow_recursive = true;
-    server_context.dns_listen = settings.dns.listen.clone();
     server_context.resolve_strategy = match settings.dns.forwarders.is_empty() {
         true => ResolveStrategy::Recursive,
         false => ResolveStrategy::Forward { upstreams: settings.dns.forwarders.clone() }
diff --git a/src/main.rs b/src/main.rs
index 5b48cf7..12fc870 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -227,6 +227,8 @@ fn setup_logger(opt_matches: &Matches) {
     }
     let config = ConfigBuilder::new()
         .add_filter_ignore_str("mio::poll")
+        .add_filter_ignore_str("rustls::client")
+        .add_filter_ignore_str("ureq::")
         .set_thread_level(LevelFilter::Off)
         .set_location_level(LevelFilter::Off)
         .set_target_level(LevelFilter::Error)
diff --git a/src/settings.rs b/src/settings.rs
index de0662e..729529f 100644
--- a/src/settings.rs
+++ b/src/settings.rs
@@ -67,6 +67,8 @@ pub struct Dns {
     #[serde(default = "default_threads")]
     pub threads: usize,
     pub forwarders: Vec<String>,
+    #[serde(default = "default_dns_bootstraps")]
+    pub bootstraps: Vec<String>,
     #[serde(default)]
     pub hosts: Vec<String>
 }
@@ -77,6 +79,7 @@ impl Default for Dns {
             listen: String::from("127.0.0.1:53"),
             threads: 20,
             forwarders: vec![String::from("94.140.14.14:53"), String::from("94.140.15.15:53")],
+            bootstraps: default_dns_bootstraps(),
             hosts: Vec::new()
         }
     }
@@ -137,4 +140,8 @@ fn default_key_files() -> Vec<String> {
         String::from("key4.toml"),
         String::from("key5.toml"),
     ]
+}
+
+fn default_dns_bootstraps() -> Vec<String> {
+    vec![String::from("9.9.9.9:53"), String::from("94.140.14.140:53")]
 }
\ No newline at end of file