feat: variable ACME_HTTP_CHALLENGE_LOCATION (#2468)

Values:
* `legacy` (default): generate location blocks for ACME HTP Challenge
  excepted when `HTTPS_METHOD=noredirect` or there is no certificate for
  the domain
* `true`: generate location blocks for ACME HTP Challenge in all cases
* `false`: do not generate location blocks for ACME HTP Challenge

This feature is currently needed because acme-companion may generate
the HTTP Challenge configuration while it was done already by nginx-proxy
(see #2465#issuecomment-2136361373).

Also sometimes a hardcoded ACME challenge location is not wanted because
the challenge validation is not done with acme-companion / Let's Encrypt,
and with a challenge location setup differently.

docs/README.md

@@ -421,6 +421,11 @@ If you are running the container in a virtualized environment (Hyper-V, VirtualB
 
 [acme-companion](https://github.com/nginx-proxy/acme-companion) is a lightweight companion container for the nginx-proxy. It allows the automated creation/renewal of SSL certificates using the ACME protocol.
 
+By default nginx-proxy generates location blocks to handle ACME HTTP Challenge, excepted when `HTTPS_METHOD=noredirect` or there is no certificate for the domain. Ths behavior can be changed with environment variable `ACME_HTTP_CHALLENGE_LOCATION`. It accepts these values:
+* `legacy`: default value; current default behavior
+* `true`: handle ACME HTTP Challenge in all cases
+* `false`: do not handle ACME HTTP Chalenge at all.
+
 ### Diffie-Hellman Groups
 
 [RFC7919 groups](https://datatracker.ietf.org/doc/html/rfc7919#appendix-A) with key lengths of 2048, 3072, and 4096 bits are [provided by `nginx-proxy`](https://github.com/nginx-proxy/nginx-proxy/dhparam). The ENV `DHPARAM_BITS` can be set to `2048` or `3072` to change from the default 4096-bit key. The DH key file will be located in the container at `/etc/nginx/dhparam/dhparam.pem`. Mounting a different `dhparam.pem` file at that location will override the RFC7919 key.

nginx.tmpl

@@ -596,6 +596,12 @@ proxy_set_header Proxy "";
     {{- end }}
     {{- $http2_enabled := parseBool (or (first (keys (groupByLabel $vhost_containers "com.github.nginx-proxy.nginx-proxy.http2.enable"))) $globals.Env.ENABLE_HTTP2 "true")}}
     {{- $http3_enabled := parseBool (or (first (keys (groupByLabel $vhost_containers "com.github.nginx-proxy.nginx-proxy.http3.enable"))) $globals.Env.ENABLE_HTTP3 "false")}}
+    {{- $acme_http_challenge := or (first (groupByKeys $vhost_containers "Env.ACME_HTTP_CHALLENGE_LOCATION")) $globals.Env.ACME_HTTP_CHALLENGE_LOCATION "legacy" }}
+    {{- $acme_http_challenge_legacy := eq $acme_http_challenge "legacy" }}
+    {{- $acme_http_challenge_enabled := false }}
+    {{- if (not $acme_http_challenge_legacy) }}
+        {{- $acme_http_challenge_enabled = parseBool $acme_http_challenge }}
+    {{- end }}
 
     {{- /* Get the SERVER_TOKENS defined by containers w/ the same vhost, falling back to "". */}}
     {{- $server_tokens := trim (or (first (groupByKeys $vhost_containers "Env.SERVER_TOKENS")) "") }}
@@ -617,6 +623,8 @@ proxy_set_header Proxy "";
         "https_method" $https_method
         "http2_enabled" $http2_enabled
         "http3_enabled" $http3_enabled
+        "acme_http_challenge_legacy" $acme_http_challenge_legacy
+        "acme_http_challenge_enabled" $acme_http_challenge_enabled
         "server_tokens" $server_tokens
         "ssl_policy" $ssl_policy
         "vhost_root" $vhost_root
@@ -741,6 +749,7 @@ server {
     listen [::]:{{ $globals.external_http_port }} {{ $default_server }};
         {{- end }}
 
+        {{- if (or $vhost.acme_http_challenge_legacy $vhost.acme_http_challenge_enabled) }}
     # Do not HTTPS redirect Let's Encrypt ACME challenge
     location ^~ /.well-known/acme-challenge/ {
         auth_basic off;
@@ -750,6 +759,7 @@ server {
         try_files $uri =404;
         break;
     }
+        {{- end }}
 
     location / {
         {{- if eq $globals.external_https_port "443" }}
@@ -776,7 +786,7 @@ server {
     listen [::]:{{ $globals.external_http_port }} {{ $default_server }};
         {{- end }}
 
-        {{- if (eq $vhost.https_method "noredirect") }}
+        {{- if (and (eq $vhost.https_method "noredirect") $vhost.acme_http_challenge_enabled) }}
     location /.well-known/acme-challenge/ {
         auth_basic off;
         allow all;

test/test_acme_http_challenge_location/acme_root/.well-known/acme-challenge/test-filename

@@ -0,0 +1 @@
+challenge-teststring

test/test_acme_http_challenge_location/certs/nginx-proxy.tld.crt

@@ -0,0 +1,70 @@
+Certificate:
+    Data:
+        Version: 3 (0x2)
+        Serial Number: 4096 (0x1000)
+    Signature Algorithm: sha256WithRSAEncryption
+        Issuer: O=nginx-proxy test suite, CN=www.nginx-proxy.tld
+        Validity
+            Not Before: Jan 10 00:08:52 2017 GMT
+            Not After : May 28 00:08:52 2044 GMT
+        Subject: CN=*.nginx-proxy.tld
+        Subject Public Key Info:
+            Public Key Algorithm: rsaEncryption
+                Public-Key: (2048 bit)
+                Modulus:
+                    00:cb:45:f4:14:9b:fe:64:85:79:4a:36:8d:3d:d1:
+                    27:d0:7c:36:28:30:e6:73:80:6f:7c:49:23:d0:6c:
+                    17:e4:44:c0:77:4d:9a:c2:bc:24:84:e3:a5:4d:ba:
+                    d2:da:51:7b:a1:2a:12:d4:c0:19:55:69:2c:22:27:
+                    2d:1a:f6:fc:4b:7f:e9:cb:a8:3c:e8:69:b8:d2:4f:
+                    de:4e:50:e2:d0:74:30:7c:42:5a:ae:aa:85:a5:b1:
+                    71:4d:c9:7e:86:8b:62:8c:3e:0d:e3:3b:c3:f5:81:
+                    0b:8c:68:79:fe:bf:10:fb:ae:ec:11:49:6d:64:5e:
+                    1a:7d:b3:92:93:4e:96:19:3a:98:04:a7:66:b2:74:
+                    61:2d:41:13:0c:a4:54:0d:2c:78:fd:b4:a3:e8:37:
+                    78:9a:de:fa:bc:2e:a8:0f:67:14:58:ce:c3:87:d5:
+                    14:0e:8b:29:7d:48:19:b2:a9:f5:b4:e8:af:32:21:
+                    67:15:7e:43:52:8b:20:cf:9f:38:43:bf:fd:c8:24:
+                    7f:52:a3:88:f2:f1:4a:14:91:2a:6e:91:6f:fb:7d:
+                    6a:78:c6:6d:2e:dd:1e:4c:2b:63:bb:3a:43:9c:91:
+                    f9:df:d3:08:13:63:86:7d:ce:e8:46:cf:f1:6c:1f:
+                    ca:f7:4c:de:d8:4b:e0:da:bc:06:d9:87:0f:ff:96:
+                    45:85
+                Exponent: 65537 (0x10001)
+        X509v3 extensions:
+            X509v3 Subject Alternative Name: 
+                DNS:*.nginx-proxy.tld
+    Signature Algorithm: sha256WithRSAEncryption
+         6e:a5:0e:e4:d3:cc:d5:b7:fc:34:75:89:4e:98:8c:e7:08:06:
+         a8:5b:ec:13:7d:83:99:a2:61:b8:d5:12:6e:c5:b4:53:4e:9a:
+         22:cd:ad:14:30:6a:7d:58:d7:23:d9:a4:2a:96:a0:40:9e:50:
+         9f:ce:f2:fe:8c:dd:9a:ac:99:39:5b:89:2d:ca:e5:3e:c3:bc:
+         03:04:1c:12:d9:6e:b8:9f:f0:3a:be:12:44:7e:a4:21:86:73:
+         af:d5:00:51:3f:2c:56:70:34:8f:26:b0:7f:b0:cf:cf:7f:f9:
+         40:6f:00:29:c4:cf:c3:b7:c2:49:3d:3f:b0:26:78:87:b9:c7:
+         6c:1b:aa:6a:1a:dd:c5:eb:f2:69:ba:6d:46:0b:92:49:b5:11:
+         3c:eb:48:c7:2f:fb:33:a6:6a:82:a2:ab:f8:1e:5f:7d:e3:b7:
+         f2:fd:f5:88:a5:09:4d:a0:bc:f4:3b:cd:d2:8b:d7:57:1f:86:
+         3b:d2:3e:a4:92:21:b0:02:0b:e9:e0:c4:1c:f1:78:e2:58:a7:
+         26:5f:4c:29:c8:23:f0:6e:12:3f:bd:ad:44:7b:0b:bd:db:ba:
+         63:8d:07:c6:9d:dc:46:cc:63:40:ba:5e:45:82:dd:9a:e5:50:
+         e8:e7:d7:27:88:fc:6f:1d:8a:e7:5c:49:28:aa:10:29:75:28:
+         c7:52:de:f9
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----

test/test_acme_http_challenge_location/certs/nginx-proxy.tld.key

@@ -0,0 +1,27 @@
+-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----

test/test_acme_http_challenge_location/test_acme_challenge_location_disabled.py

@@ -0,0 +1,30 @@
+import pytest
+
+
+def test_redirect_acme_challenge_location_disabled(docker_compose, nginxproxy, acme_challenge_path):
+    r = nginxproxy.get(
+        f"http://web1.nginx-proxy.tld/{acme_challenge_path}",
+        allow_redirects=False
+    )
+    assert r.status_code == 301
+
+def test_redirect_acme_challenge_location_enabled(docker_compose, nginxproxy, acme_challenge_path):
+    r = nginxproxy.get(
+        f"http://web2.nginx-proxy.tld/{acme_challenge_path}",
+        allow_redirects=False
+    )
+    assert r.status_code == 200
+
+def test_noderirect_acme_challenge_location_disabled(docker_compose, nginxproxy, acme_challenge_path):
+    r = nginxproxy.get(
+        f"http://web3.nginx-proxy.tld/{acme_challenge_path}",
+        allow_redirects=False
+    )
+    assert r.status_code == 404
+
+def test_noderirect_acme_challenge_location_enabled(docker_compose, nginxproxy, acme_challenge_path):
+    r = nginxproxy.get(
+        f"http://web4.nginx-proxy.tld/{acme_challenge_path}",
+        allow_redirects=False
+    )
+    assert r.status_code == 200

test/test_acme_http_challenge_location/test_acme_challenge_location_disabled.yml

@@ -0,0 +1,47 @@
+version: "2"
+
+services:
+  web1:
+    image: web
+    expose:
+      - "81"
+    environment:
+      WEB_PORTS: "81"
+      VIRTUAL_HOST: "web1.nginx-proxy.tld"
+
+  web2:
+    image: web
+    expose:
+      - "82"
+    environment:
+      WEB_PORTS: "82"
+      VIRTUAL_HOST: "web2.nginx-proxy.tld"
+      ACME_HTTP_CHALLENGE_LOCATION: "true"
+
+  web3:
+    image: web
+    expose:
+      - "83"
+    environment:
+      WEB_PORTS: "83"
+      VIRTUAL_HOST: "web3.nginx-proxy.tld"
+      HTTPS_METHOD: noredirect
+
+  web4:
+    image: web
+    expose:
+      - "84"
+    environment:
+      WEB_PORTS: "84"
+      VIRTUAL_HOST: "web4.nginx-proxy.tld"
+      HTTPS_METHOD: noredirect
+      ACME_HTTP_CHALLENGE_LOCATION: "true"
+
+  sut:
+    image: nginxproxy/nginx-proxy:test
+    environment:
+      ACME_HTTP_CHALLENGE_LOCATION: "false"
+    volumes:
+      - /var/run/docker.sock:/tmp/docker.sock:ro
+      - ./certs:/etc/nginx/certs:ro
+      - ./acme_root:/usr/share/nginx/html:ro

test/test_acme_http_challenge_location/test_acme_challenge_location_enabled.py

@@ -0,0 +1,30 @@
+import pytest
+
+
+def test_redirect_acme_challenge_location_enabled(docker_compose, nginxproxy, acme_challenge_path):
+    r = nginxproxy.get(
+        f"http://web1.nginx-proxy.tld/{acme_challenge_path}",
+        allow_redirects=False
+    )
+    assert r.status_code == 200
+
+def test_redirect_acme_challenge_location_disabled(docker_compose, nginxproxy, acme_challenge_path):
+    r = nginxproxy.get(
+        f"http://web2.nginx-proxy.tld/{acme_challenge_path}",
+        allow_redirects=False
+    )
+    assert r.status_code == 301
+
+def test_noderirect_acme_challenge_location_enabled(docker_compose, nginxproxy, acme_challenge_path):
+    r = nginxproxy.get(
+        f"http://web3.nginx-proxy.tld/{acme_challenge_path}",
+        allow_redirects=False
+    )
+    assert r.status_code == 200
+
+def test_noderirect_acme_challenge_location_disabled(docker_compose, nginxproxy, acme_challenge_path):
+    r = nginxproxy.get(
+        f"http://web4.nginx-proxy.tld/{acme_challenge_path}",
+        allow_redirects=False
+    )
+    assert r.status_code == 404

test/test_acme_http_challenge_location/test_acme_challenge_location_enabled.yml

@@ -0,0 +1,47 @@
+version: "2"
+
+services:
+  web1:
+    image: web
+    expose:
+      - "81"
+    environment:
+      WEB_PORTS: "81"
+      VIRTUAL_HOST: "web1.nginx-proxy.tld"
+
+  web2:
+    image: web
+    expose:
+      - "82"
+    environment:
+      WEB_PORTS: "82"
+      VIRTUAL_HOST: "web2.nginx-proxy.tld"
+      ACME_HTTP_CHALLENGE_LOCATION: "false"
+
+  web3:
+    image: web
+    expose:
+      - "83"
+    environment:
+      WEB_PORTS: "83"
+      VIRTUAL_HOST: "web3.nginx-proxy.tld"
+      HTTPS_METHOD: noredirect
+
+  web4:
+    image: web
+    expose:
+      - "84"
+    environment:
+      WEB_PORTS: "84"
+      VIRTUAL_HOST: "web4.nginx-proxy.tld"
+      HTTPS_METHOD: noredirect
+      ACME_HTTP_CHALLENGE_LOCATION: "false"
+
+  sut:
+    image: nginxproxy/nginx-proxy:test
+    environment:
+      ACME_HTTP_CHALLENGE_LOCATION: "true"
+    volumes:
+      - /var/run/docker.sock:/tmp/docker.sock:ro
+      - ./certs:/etc/nginx/certs:ro
+      - ./acme_root:/usr/share/nginx/html:ro

test/test_acme_http_challenge_location/test_acme_challenge_location_legacy_is_default.py

@@ -0,0 +1,16 @@
+import pytest
+
+
+def test_redirect_acme_challenge_location_legacy(docker_compose, nginxproxy, acme_challenge_path):
+    r = nginxproxy.get(
+        f"http://web1.nginx-proxy.tld/{acme_challenge_path}",
+        allow_redirects=False
+    )
+    assert r.status_code == 200
+
+def test_noderirect_acme_challenge_location_legacy(docker_compose, nginxproxy, acme_challenge_path):
+    r = nginxproxy.get(
+        f"http://web2.nginx-proxy.tld/{acme_challenge_path}",
+        allow_redirects=False
+    )
+    assert r.status_code == 404

test/test_acme_http_challenge_location/test_acme_challenge_location_legacy_is_default.yml

@@ -0,0 +1,26 @@
+version: "2"
+
+services:
+  web1:
+    image: web
+    expose:
+      - "81"
+    environment:
+      WEB_PORTS: "81"
+      VIRTUAL_HOST: "web1.nginx-proxy.tld"
+
+  web2:
+    image: web
+    expose:
+      - "82"
+    environment:
+      WEB_PORTS: "82"
+      VIRTUAL_HOST: "web2.nginx-proxy.tld"
+      HTTPS_METHOD: noredirect
+
+  sut:
+    image: nginxproxy/nginx-proxy:test
+    volumes:
+      - /var/run/docker.sock:/tmp/docker.sock:ro
+      - ./certs:/etc/nginx/certs:ro
+      - ./acme_root:/usr/share/nginx/html:ro

test/test_ssl/test_noredirect.py

@@ -19,9 +19,9 @@ def test_web2_HSTS_policy_is_inactive(docker_compose, nginxproxy):
     assert "Strict-Transport-Security" not in r.headers
 
 
-def test_web3_acme_challenge_does_work(docker_compose, nginxproxy, acme_challenge_path):
+def test_web3_acme_challenge_does_not_work(docker_compose, nginxproxy, acme_challenge_path):
     r = nginxproxy.get(
         f"http://web3.nginx-proxy.tld/{acme_challenge_path}",
         allow_redirects=False
     )
-    assert r.status_code == 200
+    assert r.status_code == 404