Presumably you’re talking about an RSA key. If so, you’ll have to massage those big integers into PKCS#1 format, at which point you can import the key using
SecKeyCreateWithData. iOS does not provide any infrastructure for doing this massage, so you can either:
Write or acquire your own general-purpose ASN.1 library, and have that do the massage for you
Write some small special-purpose ASN.1 code for this
Or, better yet, change the source of this key — which presumably has a full-featured crypto toolbox — to send you PKCS#1 data.
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Quinn “The Eskimo!”
Apple Developer Relations, Developer Technical Support, Core OS/Hardware
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