fix(dnstap source): support DNSSEC RRSIG record data

.github/CODEOWNERS

@@ -1,4 +1,5 @@
 docs/ @vectordotdev/ux-team
+lib/dnsmsg-parser/ @vectordotdev/integrations-team
 lib/file-source/ @vectordotdev/integrations-team
 lib/k8s-e2e-tests/ @vectordotdev/integrations-team
 lib/k8s-test-framework/ @vectordotdev/integrations-team

lib/dnsmsg-parser/src/dns_message_parser.rs

@@ -744,6 +744,26 @@ fn format_rdata(rdata: &RData) -> DnsParserResult<(Option<String>, Option<Vec<u8
                 );
                 Ok((Some(sig_rdata), None))
             }
+            // RSIG is a derivation of SIG but choosing to keep this duplicate code in lieu of the alternative
+            // which is to allocate to the heap with Box in order to deref.
+            DNSSECRData::RRSIG(sig) => {
+                let sig_rdata = format!(
+                    "{} {} {} {} {} {} {} {} {}",
+                    match format_record_type(sig.type_covered()) {
+                        Some(record_type) => record_type,
+                        None => String::from("Unknown record type"),
+                    },
+                    u8::from(sig.algorithm()),
+                    sig.num_labels(),
+                    sig.original_ttl(),
+                    sig.sig_expiration(), // currently in epoch convert to human readable ?
+                    sig.sig_inception(),  // currently in epoch convert to human readable ?
+                    sig.key_tag(),
+                    sig.signer_name(),
+                    BASE64.encode(sig.sig())
+                );
+                Ok((Some(sig_rdata), None))
+            }
             DNSSECRData::Unknown { code: _, rdata } => Ok((None, Some(rdata.anything().to_vec()))),
             _ => Err(DnsMessageParserError::SimpleError {
                 cause: format!("Unsupported rdata {:?}", rdata),
@@ -1117,7 +1137,7 @@ mod tests {
         dnssec::{
             rdata::{
                 dnskey::DNSKEY, ds::DS, nsec::NSEC, nsec3::NSEC3, nsec3param::NSEC3PARAM, sig::SIG,
-                DNSSECRData,
+                DNSSECRData, RRSIG,
             },
             Algorithm as DNSSEC_Algorithm, DigestType, Nsec3HashAlgorithm,
         },
@@ -1555,6 +1575,35 @@ mod tests {
         }
     }
 
+    // rsig is a derivation of the SIG record data, but the upstream crate does not handle that with an trait
+    // so there isn't really a great way to reduce code duplication here.
+    #[test]
+    fn test_format_rdata_for_rsig_type() {
+        let rdata = RData::DNSSEC(DNSSECRData::RRSIG(RRSIG::new(
+            RecordType::NULL,
+            DNSSEC_Algorithm::RSASHA256,
+            0,
+            0,
+            2,
+            1,
+            5,
+            Name::from_str("www.example.com").unwrap(),
+            vec![
+                0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,
+                23, 24, 25, 26, 27, 28, 29, 29, 31,
+            ],
+        )));
+        let rdata_text = format_rdata(&rdata);
+        assert!(rdata_text.is_ok());
+        if let Ok((parsed, raw_rdata)) = rdata_text {
+            assert!(raw_rdata.is_none());
+            assert_eq!(
+                "NULL 8 0 0 2 1 5 www.example.com AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHR8=",
+                parsed.unwrap()
+            );
+        }
+    }
+
     #[test]
     fn test_format_rdata_for_ds_type() {
         let rdata = RData::DNSSEC(DNSSECRData::DS(DS::new(