Hey folks, I am trying to implement a hmac sha256 function following this example (<https://kotlinla...

# kotlin-native

[Tobi]

Hey folks,
I am trying to implement a hmac sha256 function following this example (https://kotlinlang.slack.com/archives/C3SGXARS6/p1544768698174600?thread_ts=1541771174.265700&amp;cid=C3SGXARS6
), but that results in a SIGABRT when running it from xcode.

Could anyone give me a hand on this?

Thanks in advance.

hmac_sha_256_function.kt

[olonho]

why not follow example as is? cast of ByteArray to CValuesRef<ByteVar> doesn’t make sense, please use approach with pinned data

[Tobi]

Thanks, I did that and made it work. Posting that here in case someone else needs it

actual object Hmac256Encoder {
    @ExperimentalUnsignedTypes
    actual fun encode(key: ByteArray, value: String): ByteArray {
        val input = value.toUtf8()
        val digest = UByteArray(CC_SHA256_DIGEST_LENGTH)
        key.usePinned { keyPinned ->
            input.usePinned { inputPinned ->
                digest.usePinned { digestPinned ->
                    CCHmac(kCCHmacAlgSHA256, keyPinned.addressOf(0), key.size.convert(), inputPinned.addressOf(0), input.size.convert(), digestPinned.addressOf(0))
                }
            }
        }
        return digest.toByteArray()
    }
}

[markturnip]

Thanks for sharing @Tobi. This came up on a google search...