How to generate an RSA (PEM 1024 bit) key pair in Objective-C or Apple Swift?

Question

Objective-C

Good day, in general, you need to create an RSA (PEM 1024 bit) key pair, I tried different options, but the problem is that as it turned out under iOS, this is a rarity, I tried this way:
Method # 1
Method # 2
But this is not something that need, they are created in HEX need PEM, or how can I convert the key to PEM?