Files
vpp-maglev/internal/config/config.go

369 lines
10 KiB
Go

package config
import (
"fmt"
"net"
"os"
"regexp"
"strconv"
"strings"
"time"
"gopkg.in/yaml.v3"
)
// Frontend is the parsed and validated representation of frontend.yaml.
type Frontend struct {
ProbeIPv4Src net.IP
ProbeIPv6Src net.IP
HealthCheckNetns string
HealthChecker HealthCheckerConfig
VIPs map[string]VIP
}
// HealthCheckerConfig holds global health checker settings.
type HealthCheckerConfig struct {
TransitionHistory int
}
// VIP is a single virtual IP entry.
type VIP struct {
Description string
Address net.IP
Protocol string // "tcp", "udp", or "" (all traffic)
Port uint16 // 0 means omitted (all ports)
Backends []net.IP
HealthCheck HealthCheck
}
// HealthCheck describes how to probe backends for a VIP.
type HealthCheck struct {
Type string
HTTP *HTTPParams // non-nil for type http and https
TCP *TCPParams // non-nil for type tcp
Interval time.Duration
FastInterval time.Duration // optional; used while health counter is degraded
DownInterval time.Duration // optional; used while fully down
Timeout time.Duration
Rise int // default 2
Fall int // default 3
}
// HTTPParams holds validated parameters for http/https health checks.
type HTTPParams struct {
Path string
Host string // Host header; defaults to backend IP if empty
ResponseCodeMin int // inclusive lower bound; default 200
ResponseCodeMax int // inclusive upper bound; default 200
ResponseRegexp *regexp.Regexp // nil if not configured
ServerName string // TLS SNI; falls back to Host if empty (https only)
InsecureSkipVerify bool // skip TLS certificate verification (https only)
}
// TCPParams holds validated parameters for tcp health checks.
type TCPParams struct {
SSL bool
ServerName string
InsecureSkipVerify bool
BannerRegexp *regexp.Regexp // nil if not configured; matched against the first line sent by the server
}
// ---- raw YAML types --------------------------------------------------------
type rawConfig struct {
Maglev struct {
Frontend rawFrontend `yaml:"frontend"`
} `yaml:"maglev"`
}
type rawFrontend struct {
ProbeIPv4Src string `yaml:"probe-ipv4-src"`
ProbeIPv6Src string `yaml:"probe-ipv6-src"`
HealthCheckNetns string `yaml:"healthcheck-netns"`
HealthChecker rawHealthCheckerCfg `yaml:"healthchecker"`
VIPs map[string]rawVIP `yaml:"vips"`
}
type rawHealthCheckerCfg struct {
TransitionHistory int `yaml:"transition-history"`
}
type rawVIP struct {
Description string `yaml:"description"`
Address string `yaml:"address"`
Protocol string `yaml:"protocol"`
Port uint16 `yaml:"port"`
Backends []string `yaml:"backends"`
HealthCheck rawHealthCheck `yaml:"healthcheck"`
}
type rawHealthCheck struct {
Type string `yaml:"type"`
Params rawParams `yaml:"params"`
Interval string `yaml:"interval"`
FastInterval string `yaml:"fast-interval"`
DownInterval string `yaml:"down-interval"`
Timeout string `yaml:"timeout"`
Rise int `yaml:"rise"`
Fall int `yaml:"fall"`
}
type rawParams struct {
// HTTP / HTTPS
Path string `yaml:"path"`
Host string `yaml:"host"`
ResponseCode string `yaml:"response-code"`
ResponseRegexp string `yaml:"response-regexp"`
ServerName string `yaml:"server-name"`
InsecureSkipVerify bool `yaml:"insecure-skip-verify"`
// TCP
SSL bool `yaml:"ssl"`
}
// ---- Load ------------------------------------------------------------------
// Load reads and validates the config file at path.
func Load(path string) (*Frontend, error) {
data, err := os.ReadFile(path)
if err != nil {
return nil, fmt.Errorf("read config %q: %w", path, err)
}
return parse(data)
}
func parse(data []byte) (*Frontend, error) {
var raw rawConfig
if err := yaml.Unmarshal(data, &raw); err != nil {
return nil, fmt.Errorf("parse yaml: %w", err)
}
return convert(&raw.Maglev.Frontend)
}
func convert(r *rawFrontend) (*Frontend, error) {
f := &Frontend{}
var err error
if f.ProbeIPv4Src, err = parseOptionalIPFamily(r.ProbeIPv4Src, 4, "probe-ipv4-src"); err != nil {
return nil, err
}
if f.ProbeIPv6Src, err = parseOptionalIPFamily(r.ProbeIPv6Src, 6, "probe-ipv6-src"); err != nil {
return nil, err
}
f.HealthCheckNetns = r.HealthCheckNetns
f.HealthChecker.TransitionHistory = r.HealthChecker.TransitionHistory
if f.HealthChecker.TransitionHistory == 0 {
f.HealthChecker.TransitionHistory = 5
}
if f.HealthChecker.TransitionHistory < 1 {
return nil, fmt.Errorf("healthchecker.transition-history must be >= 1")
}
f.VIPs = make(map[string]VIP, len(r.VIPs))
for name, rv := range r.VIPs {
vip, err := convertVIP(name, &rv)
if err != nil {
return nil, fmt.Errorf("vip %q: %w", name, err)
}
f.VIPs[name] = vip
}
return f, nil
}
func convertVIP(name string, r *rawVIP) (VIP, error) {
v := VIP{
Description: r.Description,
Protocol: r.Protocol,
Port: r.Port,
}
ip := net.ParseIP(r.Address)
if ip == nil {
return VIP{}, fmt.Errorf("invalid address %q", r.Address)
}
v.Address = ip
switch r.Protocol {
case "", "tcp", "udp":
default:
return VIP{}, fmt.Errorf("protocol must be \"tcp\", \"udp\", or omitted, got %q", r.Protocol)
}
if r.Port != 0 && r.Protocol == "" {
return VIP{}, fmt.Errorf("port requires protocol to be set")
}
if r.Protocol != "" && r.Port == 0 {
return VIP{}, fmt.Errorf("protocol %q requires port to be set (1-65535)", r.Protocol)
}
if len(r.Backends) == 0 {
return VIP{}, fmt.Errorf("backends must not be empty")
}
var firstFamily int
for i, bs := range r.Backends {
ip := net.ParseIP(bs)
if ip == nil {
return VIP{}, fmt.Errorf("backend[%d] %q is not a valid IP", i, bs)
}
fam := ipFamily(ip)
if i == 0 {
firstFamily = fam
} else if fam != firstFamily {
return VIP{}, fmt.Errorf("backend[%d] %q has different address family than backend[0]", i, bs)
}
v.Backends = append(v.Backends, ip)
}
hc, err := convertHealthCheck(&r.HealthCheck)
if err != nil {
return VIP{}, fmt.Errorf("healthcheck: %w", err)
}
v.HealthCheck = hc
return v, nil
}
func convertHealthCheck(r *rawHealthCheck) (HealthCheck, error) {
h := HealthCheck{
Type: r.Type,
}
switch r.Type {
case "icmp":
// no params
case "tcp":
h.TCP = &TCPParams{
SSL: r.Params.SSL,
ServerName: r.Params.ServerName,
InsecureSkipVerify: r.Params.InsecureSkipVerify,
}
case "http", "https":
if r.Params.Path == "" {
return HealthCheck{}, fmt.Errorf("type http requires params.path")
}
min, max, err := parseCodeRange(r.Params.ResponseCode, 200)
if err != nil {
return HealthCheck{}, err
}
hp := &HTTPParams{
Path: r.Params.Path,
Host: r.Params.Host,
ResponseCodeMin: min,
ResponseCodeMax: max,
InsecureSkipVerify: r.Params.InsecureSkipVerify,
}
// TLS SNI: server-name takes precedence, falls back to host.
hp.ServerName = r.Params.ServerName
if hp.ServerName == "" {
hp.ServerName = r.Params.Host
}
if r.Params.ResponseRegexp != "" {
re, err := regexp.Compile(r.Params.ResponseRegexp)
if err != nil {
return HealthCheck{}, fmt.Errorf("invalid response-regexp %q: %w", r.Params.ResponseRegexp, err)
}
hp.ResponseRegexp = re
}
h.HTTP = hp
default:
return HealthCheck{}, fmt.Errorf("type must be \"icmp\", \"tcp\", \"http\", or \"https\", got %q", r.Type)
}
var err error
if r.Interval == "" {
return HealthCheck{}, fmt.Errorf("interval is required")
}
if h.Interval, err = time.ParseDuration(r.Interval); err != nil || h.Interval <= 0 {
return HealthCheck{}, fmt.Errorf("interval %q must be a positive duration", r.Interval)
}
if r.FastInterval != "" {
if h.FastInterval, err = time.ParseDuration(r.FastInterval); err != nil || h.FastInterval <= 0 {
return HealthCheck{}, fmt.Errorf("fast-interval %q must be a positive duration", r.FastInterval)
}
}
if r.DownInterval != "" {
if h.DownInterval, err = time.ParseDuration(r.DownInterval); err != nil || h.DownInterval <= 0 {
return HealthCheck{}, fmt.Errorf("down-interval %q must be a positive duration", r.DownInterval)
}
}
if r.Timeout == "" {
return HealthCheck{}, fmt.Errorf("timeout is required")
}
if h.Timeout, err = time.ParseDuration(r.Timeout); err != nil || h.Timeout <= 0 {
return HealthCheck{}, fmt.Errorf("timeout %q must be a positive duration", r.Timeout)
}
h.Fall = r.Fall
if h.Fall == 0 {
h.Fall = 3
}
if h.Fall < 1 {
return HealthCheck{}, fmt.Errorf("fall must be >= 1")
}
h.Rise = r.Rise
if h.Rise == 0 {
h.Rise = 2
}
if h.Rise < 1 {
return HealthCheck{}, fmt.Errorf("rise must be >= 1")
}
return h, nil
}
// ---- helpers ---------------------------------------------------------------
// parseOptionalIPFamily parses s as an IP of the given family.
// Returns nil (no error) if s is empty.
func parseOptionalIPFamily(s string, family int, field string) (net.IP, error) {
if s == "" {
return nil, nil
}
ip := net.ParseIP(s)
if ip == nil {
return nil, fmt.Errorf("%s %q is not a valid IP address", field, s)
}
if ipFamily(ip) != family {
return nil, fmt.Errorf("%s %q must be an IPv%d address", field, s, family)
}
return ip, nil
}
// ipFamily returns 4 for IPv4, 6 for IPv6.
func ipFamily(ip net.IP) int {
if ip.To4() != nil {
return 4
}
return 6
}
// parseCodeRange parses a response-code value which may be a single integer
// ("200") or an inclusive range ("200-299"). Returns (min, max, err).
func parseCodeRange(s string, defaultCode int) (min, max int, err error) {
if s == "" {
return defaultCode, defaultCode, nil
}
if idx := strings.IndexByte(s, '-'); idx > 0 {
min, err = strconv.Atoi(s[:idx])
if err != nil {
return 0, 0, fmt.Errorf("invalid response-code range %q", s)
}
max, err = strconv.Atoi(s[idx+1:])
if err != nil {
return 0, 0, fmt.Errorf("invalid response-code range %q", s)
}
return min, max, nil
}
min, err = strconv.Atoi(s)
if err != nil {
return 0, 0, fmt.Errorf("invalid response-code %q", s)
}
return min, min, nil
}