+#ifndef OPENSSL_NO_NPN
+void SSL_CTX_set_next_protos_advertised_cb(SSL_CTX *s,
+ int (*cb) (SSL *ssl,
+ const unsigned char **out,
+ unsigned int *outlen,
+ void *arg), void *arg);
+void SSL_CTX_set_next_proto_select_cb(SSL_CTX *s,
+ int (*cb) (SSL *ssl, unsigned char **out,
+ unsigned char *outlen,
+ const unsigned char *in,
+ unsigned int inlen, void *arg),
+ void *arg);
+
+int SSL_select_next_proto(unsigned char **out, unsigned char *outlen,
+ const unsigned char *in, unsigned int inlen,
+ const unsigned char *client, unsigned int client_len);
+void SSL_get0_next_proto_negotiated(const SSL *s, const unsigned char **data,
+ unsigned *len);
+
+#define OPENSSL_NPN_UNSUPPORTED 0
+#define OPENSSL_NPN_NEGOTIATED 1
+#define OPENSSL_NPN_NO_OVERLAP 2
+
+#endif