HMAC_IPAD_VAL     975 libavformat/rtmpproto.c         hmac_buf[i] ^= HMAC_IPAD_VAL;
HMAC_IPAD_VAL     988 libavformat/rtmpproto.c         hmac_buf[i] ^= HMAC_IPAD_VAL ^ HMAC_OPAD_VAL; //reuse XORed key for opad