764.c:647:24: error: ‘SSL2_MAX_CONNECTION_ID_LENGTH’ undeclared here (not in a function)
  unsigned char conn_id[SSL2_MAX_CONNECTION_ID_LENGTH];
                        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
764.c: In function ‘read_ssl_packet’:
764.c:849:19: error: ‘SSL2_MT_ERROR’ undeclared (first use in this function)
    if ((buf[0] == SSL2_MT_ERROR) && (rec_len == 3)) {
                   ^~~~~~~~~~~~~
764.c:849:19: note: each undeclared identifier is reported only once for each function it appears in
764.c: In function ‘get_server_hello’:
764.c:981:16: error: ‘SSL2_MT_SERVER_HELLO’ undeclared (first use in this function)
  if (*(p++) != SSL2_MT_SERVER_HELLO) {
                ^~~~~~~~~~~~~~~~~~~~
764.c: In function ‘send_client_master_key’:
764.c:1073:10: error: dereferencing pointer to incomplete type ‘EVP_PKEY {aka struct evp_pkey_st}’
  if (pkey->type !=EVP_PKEY_RSA) {
          ^~
764.c: In function ‘get_server_verify’:
764.c:1150:16: error: ‘SSL2_MT_SERVER_VERIFY’ undeclared (first use in this function)
  if (buf[0] != SSL2_MT_SERVER_VERIFY) {
                ^~~~~~~~~~~~~~~~~~~~~
764.c: In function ‘send_client_finished’:
764.c:1162:11: error: ‘SSL2_MT_CLIENT_FINISHED’ undeclared (first use in this function)
  buf[0] = SSL2_MT_CLIENT_FINISHED;
           ^~~~~~~~~~~~~~~~~~~~~~~
764.c: In function ‘get_server_finished’:
764.c:1175:16: error: ‘SSL2_MT_SERVER_FINISHED’ undeclared (first use in this function)
  if (buf[0] != SSL2_MT_SERVER_FINISHED) {
                ^~~~~~~~~~~~~~~~~~~~~~~