iosmacossecurity-framework

SecKeyGeneratePair public exponent

Is it possible to change the default public exponent (e) when generating an RSA key pair using SecKeyGeneratePair?

I am aware 65537 is a good default, so this is just a question about whether it is technically possible.

Solution

  • No, it's not.

    From https://github.com/unofficial-opensource-apple/Security, Security/sec/Security/SecRSAKey.c:

    /* TODO: Add support for kSecPublicExponent parameter. */
static uint8_t e[] = { 0x01, 0x00, 0x01 }; // Default is 65537