emsa_pkcs1_v1_5_encode
ret = emsa_pkcs1_v1_5_encode(m, mlen, em, (u16)k, gen_hash_type); EG(ret, err);
ret = emsa_pkcs1_v1_5_encode(m, mlen, em_, (u16)k, gen_hash_type); EG(ret, err);
ATTRIBUTE_WARN_UNUSED_RET int emsa_pkcs1_v1_5_encode(const u8 *m, u32 mlen, u8 *em, u16 emlen,