KCAPI_AKCIPHER_ENCRY(3)

📦
version 1.5.0 · 7 versions
, in fedora 43

✨ KCAPI_AKCIPHER_ENCRY ✨

okay bestie, welcome to kcapi_akcipher_encrypt(3) from the libkcapi Manual 💖 this one is giving crypto main character energy and honestly? we're obsessed.

🌸 NAME 🌸

kcapi_akcipher_encrypt — encrypt data 🔐✨

🎀 SYNOPSIS 🎀

ssize_t kcapi_akcipher_encrypt(struct kcapi_handle * handle,
                               const uint8_t * in, size_t inlen,
                               uint8_t * out, size_t outlen,
                               int access);

💅 ARGUMENTS 💅

  • handle — [in] the cipher handle, aka ur little crypto bestie 🫶
  • in — [in] the plaintext data buffer, the tea before it gets scrambled ☕
  • inlen — [in] how long the in buffer is 📏
  • out — [out] the ciphertext data buffer, where the scrambled tea goes 🌀
  • outlen — [in] how long the out buffer is 📐
  • access — [in] the kernel access type. and bestie, u have options 👑:
    • KCAPI_ACCESS_HEURISTIC — uses the internal heuristic to snag the fastest kernel access, lowkey iconic
    • KCAPI_ACCESS_VMSPLICE — uses vmsplice access
    • KCAPI_ACCESS_SENDMSG — uses sendmsg access

🦋 DESCRIPTION 🦋

not me about to tell u the coolest part first: it is perfectly legal to pass the same buffer as both the plaintext and the ciphertext pointers 💀✨ like literally the same pointer. and if u do that? after the encryption operation, ur plaintext gets overwritten with the ciphertext. gone. replaced. slay but also be aware 💅

now, the memory. it should be aligned at the page boundary using posix_memalign(sysconf(_SC_PAGESIZE)). and if it is not aligned at the page boundary, the vmsplice call may not send all data to the kernel 😭 so like, align it, bestie, it's not that deep.

if the output size is insufficiently large, -EINVAL is returned 🚫 the output buffer must be at least as large as the modululs of the uses key. periodt.

and the return situation, since i know u were wondering: on success u get the number of bytes returned by the encryption operation 🎉 and if something went wrong, u get a negative errno-style error code instead 🙈

👑 AUTHOR 👑

Stephan Mueller <smueller@chronox.de> — Author. we stan 🫶

that's the whole vibe, bestie — this was libkcapi Manual version 1.5.0, dated July 2025, and yes the manual page itself is literally named KCAPI_AKCIPHER_ENCRY(3) 🌈💖 go encrypt something iconic, ily, bye ✨

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