Fix Resolv::DNS always returning no results

app/models/ssrf_protection.rb

@@ -1,8 +1,13 @@
-module SsrfProtection
+module SSRFProtection
   extend self
 
   DNS_RESOLUTION_TIMEOUT = 2
 
+  DNS_NAMESERVERS = %w[
+    1.1.1.1
+    8.8.8.8
+  ]
+
   DISALLOWED_IP_RANGES = [
     IPAddr.new("0.0.0.0/8") # Broadcasts
   ].freeze
@@ -22,7 +27,7 @@ module SsrfProtection
     def resolve_dns(hostname)
       ip_addresses = []
 
-      Resolv::DNS.open(timeouts: DNS_RESOLUTION_TIMEOUT) do |dns|
+      Resolv::DNS.open(nameserver: DNS_NAMESERVERS, timeouts: DNS_RESOLUTION_TIMEOUT) do |dns|
         dns.each_address(hostname) do |ip_address|
           ip_addresses << IPAddr.new(ip_address.to_s)
         end

app/models/webhook/delivery.rb

@@ -70,7 +70,7 @@ class Webhook::Delivery < ApplicationRecord
 
     def resolved_ip
       return @resolved_ip if defined?(@resolved_ip)
-      @resolved_ip = SsrfProtection.resolve_public_ip(uri.host)
+      @resolved_ip = SSRFProtection.resolve_public_ip(uri.host)
     end
 
     def uri

config/initializers/inflections.rb

@@ -13,6 +13,7 @@
 # These inflection rules are supported but not enabled by default:
 ActiveSupport::Inflector.inflections(:en) do |inflect|
   inflect.acronym "SQLite"
+  inflect.acronym "SSRF"
 
   inflect.singular "quotas", "quota"
   inflect.plural "quota", "quotas"