move headers into dedicated folder

headers/auth.go

@@ -0,0 +1,221 @@
+// Package headers contains various RTSP headers.
+package headers
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/aler9/gortsplib/base"
+)
+
+// AuthMethod is an authentication method.
+type AuthMethod int
+
+const (
+	// AuthBasic is the Basic authentication method
+	AuthBasic AuthMethod = iota
+
+	// AuthDigest is the Digest authentication method
+	AuthDigest
+)
+
+// Auth is an Authenticate or a WWWW-Authenticate header.
+type Auth struct {
+	// authentication method
+	Method AuthMethod
+
+	// (optional) username
+	Username *string
+
+	// (optional) realm
+	Realm *string
+
+	// (optional) nonce
+	Nonce *string
+
+	// (optional) uri
+	URI *string
+
+	// (optional) response
+	Response *string
+
+	// (optional) opaque
+	Opaque *string
+
+	// (optional) stale
+	Stale *string
+
+	// (optional) algorithm
+	Algorithm *string
+}
+
+func findValue(v0 string) (string, string, error) {
+	if v0 == "" {
+		return "", "", nil
+	}
+
+	if v0[0] == '"' {
+		i := 1
+		for {
+			if i >= len(v0) {
+				return "", "", fmt.Errorf("apices not closed (%v)", v0)
+			}
+
+			if v0[i] == '"' {
+				return v0[1:i], v0[i+1:], nil
+			}
+
+			i++
+		}
+	}
+
+	i := 0
+	for {
+		if i >= len(v0) || v0[i] == ',' {
+			return v0[:i], v0[i:], nil
+		}
+
+		i++
+	}
+}
+
+// ReadAuth parses an Authenticate or a WWW-Authenticate header.
+func ReadAuth(v base.HeaderValue) (*Auth, error) {
+	if len(v) == 0 {
+		return nil, fmt.Errorf("value not provided")
+	}
+
+	if len(v) > 1 {
+		return nil, fmt.Errorf("value provided multiple times (%v)", v)
+	}
+
+	ha := &Auth{}
+
+	v0 := v[0]
+
+	i := strings.IndexByte(v0, ' ')
+	if i < 0 {
+		return nil, fmt.Errorf("unable to find method (%s)", v0)
+	}
+
+	switch v0[:i] {
+	case "Basic":
+		ha.Method = AuthBasic
+
+	case "Digest":
+		ha.Method = AuthDigest
+
+	default:
+		return nil, fmt.Errorf("invalid method (%s)", v0[:i])
+	}
+	v0 = v0[i+1:]
+
+	for len(v0) > 0 {
+		i := strings.IndexByte(v0, '=')
+		if i < 0 {
+			return nil, fmt.Errorf("unable to find key (%s)", v0)
+		}
+		var key string
+		key, v0 = v0[:i], v0[i+1:]
+
+		var val string
+		var err error
+		val, v0, err = findValue(v0)
+		if err != nil {
+			return nil, err
+		}
+
+		switch key {
+		case "username":
+			ha.Username = &val
+
+		case "realm":
+			ha.Realm = &val
+
+		case "nonce":
+			ha.Nonce = &val
+
+		case "uri":
+			ha.URI = &val
+
+		case "response":
+			ha.Response = &val
+
+		case "opaque":
+			ha.Opaque = &val
+
+		case "stale":
+			ha.Stale = &val
+
+		case "algorithm":
+			ha.Algorithm = &val
+
+			// ignore non-standard keys
+		}
+
+		// skip comma
+		if len(v0) > 0 && v0[0] == ',' {
+			v0 = v0[1:]
+		}
+
+		// skip spaces
+		for len(v0) > 0 && v0[0] == ' ' {
+			v0 = v0[1:]
+		}
+	}
+
+	return ha, nil
+}
+
+// Write encodes an Authenticate or a WWW-Authenticate header.
+func (ha *Auth) Write() base.HeaderValue {
+	ret := ""
+
+	switch ha.Method {
+	case AuthBasic:
+		ret += "Basic"
+
+	case AuthDigest:
+		ret += "Digest"
+	}
+
+	ret += " "
+
+	var vals []string
+
+	if ha.Username != nil {
+		vals = append(vals, "username=\""+*ha.Username+"\"")
+	}
+
+	if ha.Realm != nil {
+		vals = append(vals, "realm=\""+*ha.Realm+"\"")
+	}
+
+	if ha.Nonce != nil {
+		vals = append(vals, "nonce=\""+*ha.Nonce+"\"")
+	}
+
+	if ha.URI != nil {
+		vals = append(vals, "uri=\""+*ha.URI+"\"")
+	}
+
+	if ha.Response != nil {
+		vals = append(vals, "response=\""+*ha.Response+"\"")
+	}
+
+	if ha.Opaque != nil {
+		vals = append(vals, "opaque=\""+*ha.Opaque+"\"")
+	}
+
+	if ha.Stale != nil {
+		vals = append(vals, "stale=\""+*ha.Stale+"\"")
+	}
+
+	if ha.Algorithm != nil {
+		vals = append(vals, "algorithm=\""+*ha.Algorithm+"\"")
+	}
+
+	ret += strings.Join(vals, ", ")
+
+	return base.HeaderValue{ret}
+}