Support wildcard alias records

2026-02-08 05:56:41 +00:00 · 2025-12-16 21:33:41 -05:00
parent 56f4614899
commit cec79bf014
2 changed files with 531 additions and 22 deletions
--- a/dns/dns_records.go
+++ b/dns/dns_records.go
@@ -2,6 +2,7 @@ package dns

 import (
 	"net"
+	"strings"
 	"sync"

 	"github.com/miekg/dns"
@@ -17,21 +18,26 @@ const (

 // DNSRecordStore manages local DNS records for A and AAAA queries
 type DNSRecordStore struct {
-	mu          sync.RWMutex
-	aRecords    map[string][]net.IP // domain -> list of IPv4 addresses
-	aaaaRecords map[string][]net.IP // domain -> list of IPv6 addresses
+	mu            sync.RWMutex
+	aRecords      map[string][]net.IP // domain -> list of IPv4 addresses
+	aaaaRecords   map[string][]net.IP // domain -> list of IPv6 addresses
+	aWildcards    map[string][]net.IP // wildcard pattern -> list of IPv4 addresses
+	aaaaWildcards map[string][]net.IP // wildcard pattern -> list of IPv6 addresses
 }

 // NewDNSRecordStore creates a new DNS record store
 func NewDNSRecordStore() *DNSRecordStore {
 	return &DNSRecordStore{
-		aRecords:    make(map[string][]net.IP),
-		aaaaRecords: make(map[string][]net.IP),
+		aRecords:      make(map[string][]net.IP),
+		aaaaRecords:   make(map[string][]net.IP),
+		aWildcards:    make(map[string][]net.IP),
+		aaaaWildcards: make(map[string][]net.IP),
 	}
 }

 // AddRecord adds a DNS record mapping (A or AAAA)
 // domain should be in FQDN format (e.g., "example.com.")
+// domain can contain wildcards: * (0+ chars) and ? (exactly 1 char)
 // ip should be a valid IPv4 or IPv6 address
 func (s *DNSRecordStore) AddRecord(domain string, ip net.IP) error {
 	s.mu.Lock()
@@ -45,12 +51,23 @@ func (s *DNSRecordStore) AddRecord(domain string, ip net.IP) error {
 	// Normalize domain to lowercase
 	domain = dns.Fqdn(domain)

+	// Check if domain contains wildcards
+	isWildcard := strings.ContainsAny(domain, "*?")
+
 	if ip.To4() != nil {
 		// IPv4 address
-		s.aRecords[domain] = append(s.aRecords[domain], ip)
+		if isWildcard {
+			s.aWildcards[domain] = append(s.aWildcards[domain], ip)
+		} else {
+			s.aRecords[domain] = append(s.aRecords[domain], ip)
+		}
 	} else if ip.To16() != nil {
 		// IPv6 address
-		s.aaaaRecords[domain] = append(s.aaaaRecords[domain], ip)
+		if isWildcard {
+			s.aaaaWildcards[domain] = append(s.aaaaWildcards[domain], ip)
+		} else {
+			s.aaaaRecords[domain] = append(s.aaaaRecords[domain], ip)
+		}
 	} else {
 		return &net.ParseError{Type: "IP address", Text: ip.String()}
 	}
@@ -59,7 +76,7 @@ func (s *DNSRecordStore) AddRecord(domain string, ip net.IP) error {
 }

 // RemoveRecord removes a specific DNS record mapping
-// If ip is nil, removes all records for the domain
+// If ip is nil, removes all records for the domain (including wildcards)
 func (s *DNSRecordStore) RemoveRecord(domain string, ip net.IP) {
 	s.mu.Lock()
 	defer s.mu.Unlock()
@@ -72,33 +89,60 @@ func (s *DNSRecordStore) RemoveRecord(domain string, ip net.IP) {
 	// Normalize domain to lowercase
 	domain = dns.Fqdn(domain)

+	// Check if domain contains wildcards
+	isWildcard := strings.ContainsAny(domain, "*?")
+
 	if ip == nil {
 		// Remove all records for this domain
-		delete(s.aRecords, domain)
-		delete(s.aaaaRecords, domain)
+		if isWildcard {
+			delete(s.aWildcards, domain)
+			delete(s.aaaaWildcards, domain)
+		} else {
+			delete(s.aRecords, domain)
+			delete(s.aaaaRecords, domain)
+		}
 		return
 	}

 	if ip.To4() != nil {
 		// Remove specific IPv4 address
-		if ips, ok := s.aRecords[domain]; ok {
-			s.aRecords[domain] = removeIP(ips, ip)
-			if len(s.aRecords[domain]) == 0 {
-				delete(s.aRecords, domain)
+		if isWildcard {
+			if ips, ok := s.aWildcards[domain]; ok {
+				s.aWildcards[domain] = removeIP(ips, ip)
+				if len(s.aWildcards[domain]) == 0 {
+					delete(s.aWildcards, domain)
+				}
+			}
+		} else {
+			if ips, ok := s.aRecords[domain]; ok {
+				s.aRecords[domain] = removeIP(ips, ip)
+				if len(s.aRecords[domain]) == 0 {
+					delete(s.aRecords, domain)
+				}
 			}
 		}
 	} else if ip.To16() != nil {
 		// Remove specific IPv6 address
-		if ips, ok := s.aaaaRecords[domain]; ok {
-			s.aaaaRecords[domain] = removeIP(ips, ip)
-			if len(s.aaaaRecords[domain]) == 0 {
-				delete(s.aaaaRecords, domain)
+		if isWildcard {
+			if ips, ok := s.aaaaWildcards[domain]; ok {
+				s.aaaaWildcards[domain] = removeIP(ips, ip)
+				if len(s.aaaaWildcards[domain]) == 0 {
+					delete(s.aaaaWildcards, domain)
+				}
+			}
+		} else {
+			if ips, ok := s.aaaaRecords[domain]; ok {
+				s.aaaaRecords[domain] = removeIP(ips, ip)
+				if len(s.aaaaRecords[domain]) == 0 {
+					delete(s.aaaaRecords, domain)
+				}
 			}
 		}
 	}
 }

 // GetRecords returns all IP addresses for a domain and record type
+// First checks for exact matches, then checks wildcard patterns
 func (s *DNSRecordStore) GetRecords(domain string, recordType RecordType) []net.IP {
 	s.mu.RLock()
 	defer s.mu.RUnlock()
@@ -109,16 +153,45 @@ func (s *DNSRecordStore) GetRecords(domain string, recordType RecordType) []net.
 	var records []net.IP
 	switch recordType {
 	case RecordTypeA:
+		// Check exact match first
 		if ips, ok := s.aRecords[domain]; ok {
 			// Return a copy to prevent external modifications
 			records = make([]net.IP, len(ips))
 			copy(records, ips)
+			return records
 		}
+		// Check wildcard patterns
+		for pattern, ips := range s.aWildcards {
+			if matchWildcard(pattern, domain) {
+				records = append(records, ips...)
+			}
+		}
+		if len(records) > 0 {
+			// Return a copy
+			result := make([]net.IP, len(records))
+			copy(result, records)
+			return result
+		}
+
 	case RecordTypeAAAA:
+		// Check exact match first
 		if ips, ok := s.aaaaRecords[domain]; ok {
 			// Return a copy to prevent external modifications
 			records = make([]net.IP, len(ips))
 			copy(records, ips)
+			return records
+		}
+		// Check wildcard patterns
+		for pattern, ips := range s.aaaaWildcards {
+			if matchWildcard(pattern, domain) {
+				records = append(records, ips...)
+			}
+		}
+		if len(records) > 0 {
+			// Return a copy
+			result := make([]net.IP, len(records))
+			copy(result, records)
+			return result
 		}
 	}

@@ -126,6 +199,7 @@ func (s *DNSRecordStore) GetRecords(domain string, recordType RecordType) []net.
 }

 // HasRecord checks if a domain has any records of the specified type
+// Checks both exact matches and wildcard patterns
 func (s *DNSRecordStore) HasRecord(domain string, recordType RecordType) bool {
 	s.mu.RLock()
 	defer s.mu.RUnlock()
@@ -135,11 +209,27 @@ func (s *DNSRecordStore) HasRecord(domain string, recordType RecordType) bool {

 	switch recordType {
 	case RecordTypeA:
-		_, ok := s.aRecords[domain]
-		return ok
+		// Check exact match
+		if _, ok := s.aRecords[domain]; ok {
+			return true
+		}
+		// Check wildcard patterns
+		for pattern := range s.aWildcards {
+			if matchWildcard(pattern, domain) {
+				return true
+			}
+		}
 	case RecordTypeAAAA:
-		_, ok := s.aaaaRecords[domain]
-		return ok
+		// Check exact match
+		if _, ok := s.aaaaRecords[domain]; ok {
+			return true
+		}
+		// Check wildcard patterns
+		for pattern := range s.aaaaWildcards {
+			if matchWildcard(pattern, domain) {
+				return true
+			}
+		}
 	}

 	return false
@@ -152,6 +242,8 @@ func (s *DNSRecordStore) Clear() {

 	s.aRecords = make(map[string][]net.IP)
 	s.aaaaRecords = make(map[string][]net.IP)
+	s.aWildcards = make(map[string][]net.IP)
+	s.aaaaWildcards = make(map[string][]net.IP)
 }

 // removeIP is a helper function to remove a specific IP from a slice
@@ -164,3 +256,70 @@ func removeIP(ips []net.IP, toRemove net.IP) []net.IP {
 	}
 	return result
 }
+
+// matchWildcard checks if a domain matches a wildcard pattern
+// Pattern supports * (0+ chars) and ? (exactly 1 char)
+// Special case: *.domain.com does not match domain.com itself
+func matchWildcard(pattern, domain string) bool {
+	return matchWildcardInternal(pattern, domain, 0, 0)
+}
+
+// matchWildcardInternal performs the actual wildcard matching recursively
+func matchWildcardInternal(pattern, domain string, pi, di int) bool {
+	plen := len(pattern)
+	dlen := len(domain)
+
+	// Base cases
+	if pi == plen && di == dlen {
+		return true
+	}
+	if pi == plen {
+		return false
+	}
+
+	// Handle wildcard characters
+	if pattern[pi] == '*' {
+		// Special case: if pattern starts with "*." and we're at the beginning,
+		// ensure we don't match the domain without a prefix
+		// e.g., *.autoco.internal should not match autoco.internal
+		if pi == 0 && pi+1 < plen && pattern[pi+1] == '.' {
+			// The * must match at least one character
+			if di == dlen {
+				return false
+			}
+			// Try matching 1 or more characters before the dot
+			for i := di + 1; i <= dlen; i++ {
+				if matchWildcardInternal(pattern, domain, pi+1, i) {
+					return true
+				}
+			}
+			return false
+		}
+
+		// Normal * matching (0 or more characters)
+		// Try matching 0 characters (skip the *)
+		if matchWildcardInternal(pattern, domain, pi+1, di) {
+			return true
+		}
+		// Try matching 1+ characters
+		if di < dlen {
+			return matchWildcardInternal(pattern, domain, pi, di+1)
+		}
+		return false
+	}
+
+	if pattern[pi] == '?' {
+		// ? matches exactly one character
+		if di >= dlen {
+			return false
+		}
+		return matchWildcardInternal(pattern, domain, pi+1, di+1)
+	}
+
+	// Regular character - must match exactly
+	if di >= dlen || pattern[pi] != domain[di] {
+		return false
+	}
+
+	return matchWildcardInternal(pattern, domain, pi+1, di+1)
+}
--- a/dns/dns_records_test.go
+++ b/dns/dns_records_test.go
@@ -0,0 +1,350 @@
+package dns
+
+import (
+	"net"
+	"testing"
+)
+
+func TestWildcardMatching(t *testing.T) {
+	tests := []struct {
+		name     string
+		pattern  string
+		domain   string
+		expected bool
+	}{
+		// Basic wildcard tests
+		{
+			name:     "*.autoco.internal matches host.autoco.internal",
+			pattern:  "*.autoco.internal.",
+			domain:   "host.autoco.internal.",
+			expected: true,
+		},
+		{
+			name:     "*.autoco.internal matches longerhost.autoco.internal",
+			pattern:  "*.autoco.internal.",
+			domain:   "longerhost.autoco.internal.",
+			expected: true,
+		},
+		{
+			name:     "*.autoco.internal matches sub.host.autoco.internal",
+			pattern:  "*.autoco.internal.",
+			domain:   "sub.host.autoco.internal.",
+			expected: true,
+		},
+		{
+			name:     "*.autoco.internal does NOT match autoco.internal",
+			pattern:  "*.autoco.internal.",
+			domain:   "autoco.internal.",
+			expected: false,
+		},
+		
+		// Question mark wildcard tests
+		{
+			name:     "host-0?.autoco.internal matches host-01.autoco.internal",
+			pattern:  "host-0?.autoco.internal.",
+			domain:   "host-01.autoco.internal.",
+			expected: true,
+		},
+		{
+			name:     "host-0?.autoco.internal matches host-0a.autoco.internal",
+			pattern:  "host-0?.autoco.internal.",
+			domain:   "host-0a.autoco.internal.",
+			expected: true,
+		},
+		{
+			name:     "host-0?.autoco.internal does NOT match host-0.autoco.internal",
+			pattern:  "host-0?.autoco.internal.",
+			domain:   "host-0.autoco.internal.",
+			expected: false,
+		},
+		{
+			name:     "host-0?.autoco.internal does NOT match host-012.autoco.internal",
+			pattern:  "host-0?.autoco.internal.",
+			domain:   "host-012.autoco.internal.",
+			expected: false,
+		},
+		
+		// Combined wildcard tests
+		{
+			name:     "*.host-0?.autoco.internal matches sub.host-01.autoco.internal",
+			pattern:  "*.host-0?.autoco.internal.",
+			domain:   "sub.host-01.autoco.internal.",
+			expected: true,
+		},
+		{
+			name:     "*.host-0?.autoco.internal matches prefix.host-0a.autoco.internal",
+			pattern:  "*.host-0?.autoco.internal.",
+			domain:   "prefix.host-0a.autoco.internal.",
+			expected: true,
+		},
+		{
+			name:     "*.host-0?.autoco.internal does NOT match host-01.autoco.internal",
+			pattern:  "*.host-0?.autoco.internal.",
+			domain:   "host-01.autoco.internal.",
+			expected: false,
+		},
+		
+		// Multiple asterisks
+		{
+			name:     "*.*. autoco.internal matches any.thing.autoco.internal",
+			pattern:  "*.*.autoco.internal.",
+			domain:   "any.thing.autoco.internal.",
+			expected: true,
+		},
+		{
+			name:     "*.*.autoco.internal does NOT match single.autoco.internal",
+			pattern:  "*.*.autoco.internal.",
+			domain:   "single.autoco.internal.",
+			expected: false,
+		},
+		
+		// Asterisk in middle
+		{
+			name:     "host-*.autoco.internal matches host-anything.autoco.internal",
+			pattern:  "host-*.autoco.internal.",
+			domain:   "host-anything.autoco.internal.",
+			expected: true,
+		},
+		{
+			name:     "host-*.autoco.internal matches host-.autoco.internal (empty match)",
+			pattern:  "host-*.autoco.internal.",
+			domain:   "host-.autoco.internal.",
+			expected: true,
+		},
+		
+		// Multiple question marks
+		{
+			name:     "host-??.autoco.internal matches host-01.autoco.internal",
+			pattern:  "host-??.autoco.internal.",
+			domain:   "host-01.autoco.internal.",
+			expected: true,
+		},
+		{
+			name:     "host-??.autoco.internal does NOT match host-1.autoco.internal",
+			pattern:  "host-??.autoco.internal.",
+			domain:   "host-1.autoco.internal.",
+			expected: false,
+		},
+		
+		// Exact match (no wildcards)
+		{
+			name:     "exact.autoco.internal matches exact.autoco.internal",
+			pattern:  "exact.autoco.internal.",
+			domain:   "exact.autoco.internal.",
+			expected: true,
+		},
+		{
+			name:     "exact.autoco.internal does NOT match other.autoco.internal",
+			pattern:  "exact.autoco.internal.",
+			domain:   "other.autoco.internal.",
+			expected: false,
+		},
+		
+		// Edge cases
+		{
+			name:     "* matches anything",
+			pattern:  "*",
+			domain:   "anything.at.all.",
+			expected: true,
+		},
+		{
+			name:     "*.* matches multi.level.",
+			pattern:  "*.*",
+			domain:   "multi.level.",
+			expected: true,
+		},
+	}
+	
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := matchWildcard(tt.pattern, tt.domain)
+			if result != tt.expected {
+				t.Errorf("matchWildcard(%q, %q) = %v, want %v", tt.pattern, tt.domain, result, tt.expected)
+			}
+		})
+	}
+}
+
+func TestDNSRecordStoreWildcard(t *testing.T) {
+	store := NewDNSRecordStore()
+	
+	// Add wildcard records
+	wildcardIP := net.ParseIP("10.0.0.1")
+	err := store.AddRecord("*.autoco.internal", wildcardIP)
+	if err != nil {
+		t.Fatalf("Failed to add wildcard record: %v", err)
+	}
+	
+	// Add exact record
+	exactIP := net.ParseIP("10.0.0.2")
+	err = store.AddRecord("exact.autoco.internal", exactIP)
+	if err != nil {
+		t.Fatalf("Failed to add exact record: %v", err)
+	}
+	
+	// Test exact match takes precedence
+	ips := store.GetRecords("exact.autoco.internal.", RecordTypeA)
+	if len(ips) != 1 {
+		t.Errorf("Expected 1 IP for exact match, got %d", len(ips))
+	}
+	if !ips[0].Equal(exactIP) {
+		t.Errorf("Expected exact IP %v, got %v", exactIP, ips[0])
+	}
+	
+	// Test wildcard match
+	ips = store.GetRecords("host.autoco.internal.", RecordTypeA)
+	if len(ips) != 1 {
+		t.Errorf("Expected 1 IP for wildcard match, got %d", len(ips))
+	}
+	if !ips[0].Equal(wildcardIP) {
+		t.Errorf("Expected wildcard IP %v, got %v", wildcardIP, ips[0])
+	}
+	
+	// Test non-match (base domain)
+	ips = store.GetRecords("autoco.internal.", RecordTypeA)
+	if len(ips) != 0 {
+		t.Errorf("Expected 0 IPs for base domain, got %d", len(ips))
+	}
+}
+
+func TestDNSRecordStoreComplexWildcard(t *testing.T) {
+	store := NewDNSRecordStore()
+	
+	// Add complex wildcard pattern
+	ip1 := net.ParseIP("10.0.0.1")
+	err := store.AddRecord("*.host-0?.autoco.internal", ip1)
+	if err != nil {
+		t.Fatalf("Failed to add wildcard record: %v", err)
+	}
+	
+	// Test matching domain
+	ips := store.GetRecords("sub.host-01.autoco.internal.", RecordTypeA)
+	if len(ips) != 1 {
+		t.Errorf("Expected 1 IP for complex wildcard match, got %d", len(ips))
+	}
+	if len(ips) > 0 && !ips[0].Equal(ip1) {
+		t.Errorf("Expected IP %v, got %v", ip1, ips[0])
+	}
+	
+	// Test non-matching domain (missing prefix)
+	ips = store.GetRecords("host-01.autoco.internal.", RecordTypeA)
+	if len(ips) != 0 {
+		t.Errorf("Expected 0 IPs for domain without prefix, got %d", len(ips))
+	}
+	
+	// Test non-matching domain (wrong ? position)
+	ips = store.GetRecords("sub.host-012.autoco.internal.", RecordTypeA)
+	if len(ips) != 0 {
+		t.Errorf("Expected 0 IPs for domain with wrong ? match, got %d", len(ips))
+	}
+}
+
+func TestDNSRecordStoreRemoveWildcard(t *testing.T) {
+	store := NewDNSRecordStore()
+	
+	// Add wildcard record
+	ip := net.ParseIP("10.0.0.1")
+	err := store.AddRecord("*.autoco.internal", ip)
+	if err != nil {
+		t.Fatalf("Failed to add wildcard record: %v", err)
+	}
+	
+	// Verify it exists
+	ips := store.GetRecords("host.autoco.internal.", RecordTypeA)
+	if len(ips) != 1 {
+		t.Errorf("Expected 1 IP before removal, got %d", len(ips))
+	}
+	
+	// Remove wildcard record
+	store.RemoveRecord("*.autoco.internal", nil)
+	
+	// Verify it's gone
+	ips = store.GetRecords("host.autoco.internal.", RecordTypeA)
+	if len(ips) != 0 {
+		t.Errorf("Expected 0 IPs after removal, got %d", len(ips))
+	}
+}
+
+func TestDNSRecordStoreMultipleWildcards(t *testing.T) {
+	store := NewDNSRecordStore()
+	
+	// Add multiple wildcard patterns that don't overlap
+	ip1 := net.ParseIP("10.0.0.1")
+	ip2 := net.ParseIP("10.0.0.2")
+	ip3 := net.ParseIP("10.0.0.3")
+	
+	err := store.AddRecord("*.prod.autoco.internal", ip1)
+	if err != nil {
+		t.Fatalf("Failed to add first wildcard: %v", err)
+	}
+	
+	err = store.AddRecord("*.dev.autoco.internal", ip2)
+	if err != nil {
+		t.Fatalf("Failed to add second wildcard: %v", err)
+	}
+	
+	// Add a broader wildcard that matches both
+	err = store.AddRecord("*.autoco.internal", ip3)
+	if err != nil {
+		t.Fatalf("Failed to add third wildcard: %v", err)
+	}
+	
+	// Test domain matching only the prod pattern and the broad pattern
+	ips := store.GetRecords("host.prod.autoco.internal.", RecordTypeA)
+	if len(ips) != 2 {
+		t.Errorf("Expected 2 IPs (prod + broad), got %d", len(ips))
+	}
+	
+	// Test domain matching only the dev pattern and the broad pattern
+	ips = store.GetRecords("service.dev.autoco.internal.", RecordTypeA)
+	if len(ips) != 2 {
+		t.Errorf("Expected 2 IPs (dev + broad), got %d", len(ips))
+	}
+	
+	// Test domain matching only the broad pattern
+	ips = store.GetRecords("host.test.autoco.internal.", RecordTypeA)
+	if len(ips) != 1 {
+		t.Errorf("Expected 1 IP (broad only), got %d", len(ips))
+	}
+}
+
+func TestDNSRecordStoreIPv6Wildcard(t *testing.T) {
+	store := NewDNSRecordStore()
+	
+	// Add IPv6 wildcard record
+	ip := net.ParseIP("2001:db8::1")
+	err := store.AddRecord("*.autoco.internal", ip)
+	if err != nil {
+		t.Fatalf("Failed to add IPv6 wildcard record: %v", err)
+	}
+	
+	// Test wildcard match for IPv6
+	ips := store.GetRecords("host.autoco.internal.", RecordTypeAAAA)
+	if len(ips) != 1 {
+		t.Errorf("Expected 1 IPv6 for wildcard match, got %d", len(ips))
+	}
+	if len(ips) > 0 && !ips[0].Equal(ip) {
+		t.Errorf("Expected IPv6 %v, got %v", ip, ips[0])
+	}
+}
+
+func TestHasRecordWildcard(t *testing.T) {
+	store := NewDNSRecordStore()
+	
+	// Add wildcard record
+	ip := net.ParseIP("10.0.0.1")
+	err := store.AddRecord("*.autoco.internal", ip)
+	if err != nil {
+		t.Fatalf("Failed to add wildcard record: %v", err)
+	}
+	
+	// Test HasRecord with wildcard match
+	if !store.HasRecord("host.autoco.internal.", RecordTypeA) {
+		t.Error("Expected HasRecord to return true for wildcard match")
+	}
+	
+	// Test HasRecord with non-match
+	if store.HasRecord("autoco.internal.", RecordTypeA) {
+		t.Error("Expected HasRecord to return false for base domain")
+	}
+}