Add cname harvester

modules/dev/cname-harvest.lua

@@ -0,0 +1,54 @@
+-- Description: Query for CNAMES to find subdomains
+-- Version: 0.1.0
+-- Source: subdomains
+-- License: GPL-3.0
+
+function iter(r)
+    if r == nil then
+        return
+    end
+
+    m = regex_find("(.+)\\.$", r)
+    if last_err() then return end
+
+    if m == nil then
+        return
+    end
+    r = m[2]
+
+    domain = psl_domain_from_dns_name(r)
+    if last_err() then return end
+
+    domain_id = db_add('domain', {
+        value=domain,
+    })
+    if last_err() then return end
+
+    if domain_id ~= nil then
+        db_add('subdomain', {
+            domain_id=domain_id,
+            value=r,
+        })
+        if last_err() then return end
+    end
+end
+
+function run(arg)
+    records = dns(arg['value'], 'CNAME')
+    if last_err() then return end
+
+    if records['success'] == nil then return end
+    records = records['success']
+
+    -- there is a bug in struct -> lua that causes tables to be zero indexed
+    -- this checks if there's something at index 0 but uses index 1 if this is fixed
+    i = 0
+    if records[i] == nil then i = 1 end
+
+    while records[i] ~= nil do
+        r = records[i]['CNAME']
+        iter(r)
+        if last_err() then return end
+        i = i+1
+    end
+end