core/common/matcher/matcher.go
2022-03-16 19:40:29 +08:00

100 lines
2.0 KiB
Go

package matcher
import (
"net"
"strings"
"github.com/gobwas/glob"
)
// Matcher is a generic pattern matcher,
// it gives the match result of the given pattern for specific v.
type Matcher interface {
Match(v string) bool
}
// NewMatcher creates a Matcher for the given pattern.
// The acutal Matcher depends on the pattern:
// IP Matcher if pattern is a valid IP address.
// CIDR Matcher if pattern is a valid CIDR address.
// Domain Matcher if both of the above are not.
func NewMatcher(pattern string) Matcher {
if pattern == "" {
return nil
}
if ip := net.ParseIP(pattern); ip != nil {
return IPMatcher(ip)
}
if _, inet, err := net.ParseCIDR(pattern); err == nil {
return CIDRMatcher(inet)
}
return DomainMatcher(pattern)
}
type ipMatcher struct {
ip net.IP
}
// IPMatcher creates a Matcher for a specific IP address.
func IPMatcher(ip net.IP) Matcher {
return &ipMatcher{
ip: ip,
}
}
func (m *ipMatcher) Match(ip string) bool {
if m == nil {
return false
}
return m.ip.Equal(net.ParseIP(ip))
}
type cidrMatcher struct {
ipNet *net.IPNet
}
// CIDRMatcher creates a Matcher for a specific CIDR notation IP address.
func CIDRMatcher(inet *net.IPNet) Matcher {
return &cidrMatcher{
ipNet: inet,
}
}
func (m *cidrMatcher) Match(ip string) bool {
if m == nil || m.ipNet == nil {
return false
}
return m.ipNet.Contains(net.ParseIP(ip))
}
type domainMatcher struct {
pattern string
glob glob.Glob
}
// DomainMatcher creates a Matcher for a specific domain pattern,
// the pattern can be a plain domain such as 'example.com',
// a wildcard such as '*.exmaple.com' or a special wildcard '.example.com'.
func DomainMatcher(pattern string) Matcher {
p := pattern
if strings.HasPrefix(pattern, ".") {
p = pattern[1:] // trim the prefix '.'
pattern = "*" + p
}
return &domainMatcher{
pattern: p,
glob: glob.MustCompile(pattern),
}
}
func (m *domainMatcher) Match(domain string) bool {
if m == nil || m.glob == nil {
return false
}
if domain == m.pattern {
return true
}
return m.glob.Match(domain)
}