implement outgoing tls reports

we were already accepting, processing and displaying incoming tls reports. now
we start tracking TLS connection and security-policy-related errors for
outgoing message deliveries as well. we send reports once a day, to the
reporting addresses specified in TLSRPT records (rua) of a policy domain. these
reports are about MTA-STS policies and/or DANE policies, and about
STARTTLS-related failures.

sending reports is enabled by default, but can be disabled through setting
NoOutgoingTLSReports in mox.conf.

only at the end of the implementation process came the realization that the
TLSRPT policy domain for DANE (MX) hosts are separate from the TLSRPT policy
for the recipient domain, and that MTA-STS and DANE TLS/policy results are
typically delivered in separate reports. so MX hosts need their own TLSRPT
policies.

config for the per-host TLSRPT policy should be added to mox.conf for existing
installs, in field HostTLSRPT. it is automatically configured by quickstart for
new installs. with a HostTLSRPT config, the "dns records" and "dns check" admin
pages now suggest the per-host TLSRPT record. by creating that record, you're
requesting TLS reports about your MX host.

gathering all the TLS/policy results is somewhat tricky. the tentacles go
throughout the code. the positive result is that the TLS/policy-related code
had to be cleaned up a bit. for example, the smtpclient TLS modes now reflect
reality better, with independent settings about whether PKIX and/or DANE
verification has to be done, and/or whether verification errors have to be
ignored (e.g. for tls-required: no header). also, cached mtasts policies of
mode "none" are now cleaned up once the MTA-STS DNS record goes away.

webadmin/adminapi.json

@@ -807,6 +807,99 @@
 				}
 			],
 			"Returns": []
+		},
+		{
+			"Name": "TLSRPTResults",
+			"Docs": "TLSRPTResults returns all TLSRPT results in the database.",
+			"Params": [],
+			"Returns": [
+				{
+					"Name": "r0",
+					"Typewords": [
+						"[]",
+						"TLSResult"
+					]
+				}
+			]
+		},
+		{
+			"Name": "TLSRPTResultsPolicyDomain",
+			"Docs": "TLSRPTResultsPolicyDomain returns the TLS results for a domain.",
+			"Params": [
+				{
+					"Name": "policyDomain",
+					"Typewords": [
+						"string"
+					]
+				}
+			],
+			"Returns": [
+				{
+					"Name": "r0",
+					"Typewords": [
+						"Domain"
+					]
+				},
+				{
+					"Name": "r1",
+					"Typewords": [
+						"[]",
+						"TLSResult"
+					]
+				}
+			]
+		},
+		{
+			"Name": "LookupTLSRPTRecord",
+			"Docs": "LookupTLSRPTRecord looks up a TLSRPT record and returns the parsed form, original txt\nform from DNS, and error with the TLSRPT record as a string.",
+			"Params": [
+				{
+					"Name": "domain",
+					"Typewords": [
+						"string"
+					]
+				}
+			],
+			"Returns": [
+				{
+					"Name": "record",
+					"Typewords": [
+						"nullable",
+						"TLSRPTRecord"
+					]
+				},
+				{
+					"Name": "txt",
+					"Typewords": [
+						"string"
+					]
+				},
+				{
+					"Name": "errstr",
+					"Typewords": [
+						"string"
+					]
+				}
+			]
+		},
+		{
+			"Name": "TLSRPTRemoveResults",
+			"Docs": "TLSRPTRemoveResults removes the TLS results for a domain for the given day. If\nday is empty, all results are removed.",
+			"Params": [
+				{
+					"Name": "domain",
+					"Typewords": [
+						"string"
+					]
+				},
+				{
+					"Name": "day",
+					"Typewords": [
+						"string"
+					]
+				}
+			],
+			"Returns": []
 		}
 	],
 	"Sections": [],
@@ -879,7 +972,14 @@
 					]
 				},
 				{
-					"Name": "TLSRPT",
+					"Name": "HostTLSRPT",
+					"Docs": "",
+					"Typewords": [
+						"TLSRPTCheckResult"
+					]
+				},
+				{
+					"Name": "DomainTLSRPT",
 					"Docs": "",
 					"Typewords": [
 						"TLSRPTCheckResult"
@@ -2148,6 +2248,13 @@
 						"[]",
 						"Pair"
 					]
+				},
+				{
+					"Name": "PolicyText",
+					"Docs": "Text that make up the policy, as retrieved. We didn't store this in the past. If empty, policy can be reconstructed from Policy field. Needed by TLSRPT.",
+					"Typewords": [
+						"string"
+					]
 				}
 			]
 		},
@@ -2183,6 +2290,13 @@
 						"string"
 					]
 				},
+				{
+					"Name": "HostReport",
+					"Docs": "Report for host TLSRPT record, as opposed to domain TLSRPT record.",
+					"Typewords": [
+						"bool"
+					]
+				},
 				{
 					"Name": "Report",
 					"Docs": "",
@@ -2290,7 +2404,7 @@
 					"Name": "policy-type",
 					"Docs": "",
 					"Typewords": [
-						"string"
+						"PolicyType"
 					]
 				},
 				{
@@ -2367,6 +2481,7 @@
 					"Name": "receiving-mx-helo",
 					"Docs": "",
 					"Typewords": [
+						"nullable",
 						"string"
 					]
 				},
@@ -3672,6 +3787,76 @@
 					]
 				}
 			]
+		},
+		{
+			"Name": "TLSResult",
+			"Docs": "TLSResult is stored in the database to track TLS results per policy domain, day\nand recipient domain. These records will be included in TLS reports.",
+			"Fields": [
+				{
+					"Name": "ID",
+					"Docs": "",
+					"Typewords": [
+						"int64"
+					]
+				},
+				{
+					"Name": "PolicyDomain",
+					"Docs": "Domain with TLSRPT DNS record, with addresses that will receive reports. Either a recipient domain (for MTA-STS policies) or an (MX) host (for DANE policies). Unicode.",
+					"Typewords": [
+						"string"
+					]
+				},
+				{
+					"Name": "DayUTC",
+					"Docs": "DayUTC is of the form yyyymmdd.",
+					"Typewords": [
+						"string"
+					]
+				},
+				{
+					"Name": "RecipientDomain",
+					"Docs": "Reports are sent per policy domain. When delivering a message to a recipient domain, we can get multiple TLSResults, typically one for MTA-STS, and one or more for DANE (one for each MX target, or actually TLSA base domain). We track recipient domain so we can display successes/failures for delivery of messages to a recipient domain in the admin pages. Unicode.",
+					"Typewords": [
+						"string"
+					]
+				},
+				{
+					"Name": "Created",
+					"Docs": "",
+					"Typewords": [
+						"timestamp"
+					]
+				},
+				{
+					"Name": "Updated",
+					"Docs": "",
+					"Typewords": [
+						"timestamp"
+					]
+				},
+				{
+					"Name": "IsHost",
+					"Docs": "Result is for host (e.g. DANE), not recipient domain (e.g. MTA-STS).",
+					"Typewords": [
+						"bool"
+					]
+				},
+				{
+					"Name": "SendReport",
+					"Docs": "Whether to send a report. TLS results for delivering messages with TLS reports will be recorded, but will not cause a report to be sent.",
+					"Typewords": [
+						"bool"
+					]
+				},
+				{
+					"Name": "Results",
+					"Docs": "Results is updated for each TLS attempt.",
+					"Typewords": [
+						"[]",
+						"Result"
+					]
+				}
+			]
 		}
 	],
 	"Ints": [],
@@ -3739,6 +3924,27 @@
 				}
 			]
 		},
+		{
+			"Name": "PolicyType",
+			"Docs": "PolicyType indicates the policy success/failure results are for.",
+			"Values": [
+				{
+					"Name": "TLSA",
+					"Value": "tlsa",
+					"Docs": "For DANE, against a mail host (not recipient domain)."
+				},
+				{
+					"Name": "STS",
+					"Value": "sts",
+					"Docs": "For MTA-STS, against a recipient domain (not a mail host)."
+				},
+				{
+					"Name": "NoPolicyFound",
+					"Value": "no-policy-found",
+					"Docs": "Recipient domain did not have MTA-STS policy, or mail host (TSLA base domain)\ndid not have DANE TLSA records."
+				}
+			]
+		},
 		{
 			"Name": "ResultType",
 			"Docs": "ResultType represents a TLS error.",