How to create a .pem file with aes key

问题

i have to create an aes-256 key and store it in a .pem file. I am using RAND_bytes() to simply create a 256 bit random key. After this how can i save this to a pem file. I have looked at Reading and writing rsa keys to a pem file in C and openssl pem. But i am not working with RSA keys.

I suspect my task is much simpler like create pem from base64 but not much help.

PS: This key will be used to encrypt a self signed digital certificate.

EDIT: looking around more i found that i could use bio to covert to pem, something likePEM_write_bio_PrivateKey but it takes EVP_PKEY format as argument. So how can i convert char buf to EVP_PKEY. i found d2i_PublicKey but it involves RSA and am unsure how RSA would fit into picture here.

回答1:

AES key is just a random byte array. You can simple store the bytes in a file without any structure.

回答2:

You can convert aes key to .pem by using PEMWriter class of bouncyCastle library.

http://www.bouncycastle.org/documentation.html

来源：https://stackoverflow.com/questions/35681704/how-to-create-a-pem-file-with-aes-key