feat: support for DNS-01 challenge w/ acme.sh DNS API

Co-authored-by: Nicolas Duchon <nicolas.duchon@gmail.com>
Co-authored-by: David Michaluk <d@michal.uk>

app/letsencrypt_service

@@ -151,7 +151,41 @@ function update_cert {
 
     # CLI parameters array used for --issue
     local -a params_issue_arr
-    params_issue_arr+=(--webroot /usr/share/nginx/html)
+
+    # ACME challenge type
+    local -n acme_challenge="ACME_${cid}_CHALLENGE"
+    if [[ -z "${acme_challenge}" ]]; then
+        acme_challenge="${ACME_CHALLENGE:-HTTP-01}"
+    fi
+
+    if [[ "$acme_challenge" == "HTTP-01" ]]; then
+        # HTTP-01 challenge
+        params_issue_arr+=(--webroot /usr/share/nginx/html)
+    elif [[ "$acme_challenge" == "DNS-01" ]]; then
+        # DNS-01 challenge
+        local -n acmesh_dns_config="ACMESH_${cid}_DNS_API_CONFIG"
+
+        local acmesh_dns_api="${acmesh_dns_config[DNS_API]}"
+        if [[ -z "$acmesh_dns_api" ]]; then
+            echo "Error: missing acme.sh DNS API for DNS challenge"
+            return 1
+        fi
+        params_issue_arr+=(--dns "$acmesh_dns_api")
+
+        # Loop over defined variable for acme.sh DNS api config
+        local -a dns_api_keys
+        for key in "${!acmesh_dns_config[@]}"; do
+            [[ "$key" == "DNS_API" ]] && continue
+            dns_api_keys+=("$key")
+            local value="${acmesh_dns_config[$key]}"
+            declare -x "$key"="$value"
+        done
+
+        echo "Info: DNS challenge using $acmesh_dns_api DNS API with the following keys: ${dns_api_keys[*]}"
+    else 
+        echo "Error: unknown ACME challenge method: $acme_challenge"
+        return 1
+    fi
 
     local -n cert_keysize="LETSENCRYPT_${cid}_KEYSIZE"
     if [[ -z "$cert_keysize" ]] || \
@@ -349,7 +383,7 @@ function update_cert {
         # Add all the domains to certificate
         params_issue_arr+=(--domain "$domain")
         # If enabled, add location configuration for the domain
-        if parse_true "${ACME_HTTP_CHALLENGE_LOCATION:=false}"; then
+        if [[ "$acme_challenge" == "HTTP-01" ]] && parse_true "${ACME_HTTP_CHALLENGE_LOCATION:=false}"; then
             add_location_configuration "$domain" || reload_nginx
         fi
     done
@@ -361,6 +395,16 @@ function update_cert {
 
     local acmesh_return=$?
 
+    # DNS challenge: clean environment variables
+    if [[ "$acme_challenge" == "DNS-01" ]]; then
+        local -n acmesh_dns_config="ACMESH_${cid}_DNS_API_CONFIG"
+        # Loop over defined variable for acme.sh DNS api config
+        for key in "${!acmesh_dns_config[@]}"; do
+            [[ "$key" == "DNS_API" ]] && continue
+            unset "$key"
+        done
+    fi
+
     # 0 = success, 2 = RENEW_SKIP
     if [[ $acmesh_return == 0 || $acmesh_return == 2 ]]; then
         for domain in "${hosts_array[@]}"; do

app/letsencrypt_service_data.tmpl

@@ -26,6 +26,8 @@ LETSENCRYPT_CONTAINERS=(
         {{ $STAGING := trim (coalesce $container.Env.LETSENCRYPT_TEST "") }}
         {{ $EMAIL := trim (coalesce $container.Env.LETSENCRYPT_EMAIL "") }}
         {{ $CA_URI := trim (coalesce $container.Env.ACME_CA_URI "") }}
+        {{ $ACME_CHALLENGE := trim (coalesce $container.Env.ACME_CHALLENGE "") }}
+        {{ $ACMESH_DNS_API_CONFIG := fromYaml (coalesce $container.Env.ACMESH_DNS_API_CONFIG "") }}
         {{ $PREFERRED_CHAIN := trim (coalesce $container.Env.ACME_PREFERRED_CHAIN "") }}
         {{ $OCSP := trim (coalesce $container.Env.ACME_OCSP "") }}
         {{ $EAB_KID := trim (coalesce $container.Env.ACME_EAB_KID "") }}
@@ -47,6 +49,14 @@ LETSENCRYPT_CONTAINERS=(
                 {{- "\n" }}LETSENCRYPT_{{ $cid }}_{{ $hostHash }}_TEST="{{ $STAGING }}"
                 {{- "\n" }}LETSENCRYPT_{{ $cid }}_{{ $hostHash }}_EMAIL="{{ $EMAIL }}"
                 {{- "\n" }}ACME_{{ $cid }}_{{ $hostHash }}_CA_URI="{{ $CA_URI }}"
+                {{- "\n" }}ACME_{{ $cid }}_{{ $hostHash }}_CHALLENGE="{{ $ACME_CHALLENGE }}"
+                {{- if $ACMESH_DNS_API_CONFIG }}
+                    {{- "\n" }}declare -A ACMESH_{{ $cid }}_{{ $hostHash }}_DNS_API_CONFIG=(
+                    {{- range $key, $value := $ACMESH_DNS_API_CONFIG }}
+                        {{- "\n\t" }}['{{ $key }}']='{{ $value }}'
+                    {{- end }}
+                    {{- "\n" }})
+                {{- end }}
                 {{- "\n" }}ACME_{{ $cid }}_{{ $hostHash }}_PREFERRED_CHAIN="{{ $PREFERRED_CHAIN }}"
                 {{- "\n" }}ACME_{{ $cid }}_{{ $hostHash }}_OCSP="{{ $OCSP }}"
                 {{- "\n" }}ACME_{{ $cid }}_{{ $hostHash }}_EAB_KID="{{ $EAB_KID }}"
@@ -69,6 +79,14 @@ LETSENCRYPT_CONTAINERS=(
             {{- "\n" }}LETSENCRYPT_{{ $cid }}_TEST="{{ $STAGING }}"
             {{- "\n" }}LETSENCRYPT_{{ $cid }}_EMAIL="{{ $EMAIL }}"
             {{- "\n" }}ACME_{{ $cid }}_CA_URI="{{ $CA_URI }}"
+            {{- "\n" }}ACME_{{ $cid }}_CHALLENGE="{{ $ACME_CHALLENGE }}"
+            {{- if $ACMESH_DNS_API_CONFIG }}
+                {{- "\n" }}declare -A ACMESH_{{ $cid }}_DNS_API_CONFIG=(
+                {{- range $key, $value := $ACMESH_DNS_API_CONFIG }}
+                    {{- "\n\t" }}['{{ $key }}']='{{ $value }}'
+                {{- end }}
+                {{- "\n" }})
+            {{- end }}
             {{- "\n" }}ACME_{{ $cid }}_PREFERRED_CHAIN="{{ $PREFERRED_CHAIN }}"
             {{- "\n" }}ACME_{{ $cid }}_OCSP="{{ $OCSP }}"
             {{- "\n" }}ACME_{{ $cid }}_EAB_KID="{{ $EAB_KID }}"

app/start.sh

@@ -7,7 +7,9 @@ term_handler() {
 
     # shellcheck source=functions.sh
     source /app/functions.sh
-    remove_all_location_configurations
+    if parse_true "${ACME_HTTP_CHALLENGE_LOCATION:=false}"; then
+        remove_all_location_configurations
+    fi
     remove_all_standalone_configurations
 
     exit 0