add pkgs from core

admission/admission.go

@@ -0,0 +1,86 @@
+package admission
+
+import (
+	"net"
+	"strconv"
+
+	admission_pkg "github.com/go-gost/core/admission"
+	"github.com/go-gost/core/logger"
+	"github.com/go-gost/x/internal/util/matcher"
+)
+
+type options struct {
+	logger logger.Logger
+}
+
+type Option func(opts *options)
+
+func LoggerOption(logger logger.Logger) Option {
+	return func(opts *options) {
+		opts.logger = logger
+	}
+}
+
+type admission struct {
+	matchers []matcher.Matcher
+	reversed bool
+	options  options
+}
+
+// NewAdmission creates and initializes a new Admission using matchers as its match rules.
+// The rules will be reversed if the reversed is true.
+func NewAdmission(reversed bool, matchers []matcher.Matcher, opts ...Option) admission_pkg.Admission {
+	options := options{}
+	for _, opt := range opts {
+		opt(&options)
+	}
+	return &admission{
+		matchers: matchers,
+		reversed: reversed,
+		options:  options,
+	}
+}
+
+// NewAdmissionPatterns creates and initializes a new Admission using matcher patterns as its match rules.
+// The rules will be reversed if the reverse is true.
+func NewAdmissionPatterns(reversed bool, patterns []string, opts ...Option) admission_pkg.Admission {
+	var matchers []matcher.Matcher
+	for _, pattern := range patterns {
+		if m := matcher.NewMatcher(pattern); m != nil {
+			matchers = append(matchers, m)
+		}
+	}
+	return NewAdmission(reversed, matchers, opts...)
+}
+
+func (p *admission) Admit(addr string) bool {
+	if addr == "" || p == nil || len(p.matchers) == 0 {
+		p.options.logger.Debugf("admission: %v is denied", addr)
+		return false
+	}
+
+	// try to strip the port
+	if host, port, _ := net.SplitHostPort(addr); host != "" && port != "" {
+		if p, _ := strconv.Atoi(port); p > 0 { // port is valid
+			addr = host
+		}
+	}
+
+	var matched bool
+	for _, matcher := range p.matchers {
+		if matcher == nil {
+			continue
+		}
+		if matcher.Match(addr) {
+			matched = true
+			break
+		}
+	}
+
+	b := !p.reversed && matched ||
+		p.reversed && !matched
+	if !b {
+		p.options.logger.Debugf("admission: %v is denied", addr)
+	}
+	return b
+}