Initial zhanlu OpenAI proxy

internal/auth/rsa.go

@@ -0,0 +1,37 @@
+package auth
+
+import (
+	"crypto/rand"
+	"crypto/rsa"
+	"crypto/x509"
+	"encoding/base64"
+	"encoding/pem"
+	"errors"
+)
+
+func ParsePublicKey(pemText string) (*rsa.PublicKey, error) {
+	block, _ := pem.Decode([]byte(pemText))
+	if block == nil {
+		return nil, errors.New("invalid public key PEM")
+	}
+	pub, err := x509.ParsePKIXPublicKey(block.Bytes)
+	if err != nil {
+		return nil, err
+	}
+	rsaPub, ok := pub.(*rsa.PublicKey)
+	if !ok {
+		return nil, errors.New("public key is not RSA")
+	}
+	return rsaPub, nil
+}
+
+func EncryptAuthorization(pub *rsa.PublicKey, plaintext string) (string, error) {
+	if pub == nil {
+		return "", errors.New("public key is required")
+	}
+	out, err := rsa.EncryptPKCS1v15(rand.Reader, pub, []byte(plaintext))
+	if err != nil {
+		return "", err
+	}
+	return base64.StdEncoding.EncodeToString(out), nil
+}