fix

internal/ingest/shield.go

@@ -0,0 +1,114 @@
+package ingest
+
+import (
+	"encoding/json"
+	"fmt"
+	"net"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/gosnmp/gosnmp"
+)
+
+type timeWindow struct {
+	Days  []int  `json:"days"`
+	Start string `json:"start"`
+	End   string `json:"end"`
+}
+
+func ipMatchesCIDR(ip net.IP, cidr string) bool {
+	cidr = strings.TrimSpace(cidr)
+	if cidr == "" {
+		return false
+	}
+	if !strings.Contains(cidr, "/") {
+		p := net.ParseIP(cidr)
+		return p != nil && p.Equal(ip)
+	}
+	_, network, err := net.ParseCIDR(cidr)
+	if err != nil {
+		return false
+	}
+	return network.Contains(ip)
+}
+
+func inTimeWindows(now time.Time, jsonStr string) bool {
+	s := strings.TrimSpace(jsonStr)
+	if s == "" || s == "null" {
+		return true
+	}
+	var windows []timeWindow
+	if err := json.Unmarshal([]byte(s), &windows); err != nil || len(windows) == 0 {
+		return true
+	}
+	tod := now.Hour()*60 + now.Minute()
+	wd := int(now.Weekday())
+	for _, w := range windows {
+		if len(w.Days) > 0 {
+			ok := false
+			for _, d := range w.Days {
+				if d == wd {
+					ok = true
+					break
+				}
+			}
+			if !ok {
+				continue
+			}
+		}
+		start := parseHHMM(w.Start)
+		end := parseHHMM(w.End)
+		if start < 0 || end < 0 {
+			continue
+		}
+		if start <= end {
+			if tod >= start && tod <= end {
+				return true
+			}
+		} else {
+			if tod >= start || tod <= end {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+func parseHHMM(s string) int {
+	s = strings.TrimSpace(s)
+	if s == "" {
+		return -1
+	}
+	parts := strings.Split(s, ":")
+	if len(parts) != 2 {
+		return -1
+	}
+	h, err1 := strconv.Atoi(parts[0])
+	m, err2 := strconv.Atoi(parts[1])
+	if err1 != nil || err2 != nil || h < 0 || h > 23 || m < 0 || m > 59 {
+		return -1
+	}
+	return h*60 + m
+}
+
+func varbindFingerprint(pkt *gosnmp.SnmpPacket) string {
+	var b strings.Builder
+	for _, v := range pkt.Variables {
+		b.WriteString(v.Name)
+		b.WriteByte('=')
+		b.WriteString(fmtVarbindValue(v))
+		b.WriteByte(';')
+	}
+	return b.String()
+}
+
+func fmtVarbindValue(v gosnmp.SnmpPDU) string {
+	switch v.Type {
+	case gosnmp.OctetString:
+		if bb, ok := v.Value.([]byte); ok {
+			return string(bb)
+		}
+	}
+	return fmt.Sprintf("%v", v.Value)
+}