KCAPI_AKCIPHER_STREA(3)

💖 KCAPI_AKCIPHER_STREA — kcapi_akcipher_stream_init_vfy 💖

okay bestie, welcome to the Programming Interface section of the libkcapi manual, page KCAPI_AKCIPHER_STREA(3). this one's about kicking off a signature verification operation, but like… the stream version. yes, streaming. we love a slow-burn. 🦋

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✨ NAME ✨

kcapi_akcipher_stream_init_vfy — start an signature verification operation (stream) 💅

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🌸 SYNOPSIS 🌸

ssize_t kcapi_akcipher_stream_init_vfy(struct kcapi_handle * handle,
                                       struct iovec * iov,
                                       size_t iovlen);

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🎀 ARGUMENTS 🎀

• handle — [in] the cipher handle. your main character. hold onto it. 🫶
• iov — [in] scatter/gather list with data to be verified. if you're passing an array of iov entries, this is the pointer to the first iov entry. see sendmsg(2) for the deets on how iov is supposed to be used, fr fr. this pointer may be NULL if there's no data to be verified available at the point of the call. lowkey valid.
• iovlen — [in] number of scatter/gather list elements. and listen: if iov is NULL, this value must be zero. no cap. zero. 🙈

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💜 DESCRIPTION 💜

a stream signature verification operation gets started with this call. that's the whole vibe. ✨

once you've done that, you can hit up kcapi_akcipher_stream_update multiple successive times to send more plaintext data to be verified. but bestie, the last invocation that supplies data must be done with kcapi_akcipher_stream_update_last. don't skip that one, it's giving final boss energy. 👑

the kernel buffers the input until kcapi_akcipher_stream_op picks up the verified data. once the plaintext is verified during the kcapi_cipher_stream_op, it gets removed from the kernel buffer. poof. gone. iconic. 🧚

also!! the function calls of kcapi_akcipher_stream_update and kcapi_akcipher_stream_op can be mixed, even by multiple threads of an application. multitasking queen behavior. 🌈

returns: number of bytes sent to the kernel upon success; a negative errno-style error code if an error occurred. so like, if it's negative… something went wrong, and we do NOT stan. 💀

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👑 AUTHOR 👑

• Stephan Mueller <smueller@chronox.de>
  • Author. yes, THE author. respect the legend. ⭐

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🌈 COPYRIGHT 🌈

libkcapi Manual 1.5.0 — July 2025 — and that's the KCAPI_AKCIPHER_STREA(3) page, bestie. go forth and verify those signatures, you absolute icon. mwah. 💖🎀🦋💅