crypto_cipher_decrypt_one(9)

💅 crypto_cipher_decrypt_one — like, the kernel API manual, bestie

okay so this is a page from the Kernel API Manual and it's about crypto_cipher_decrypt_one, which is literally the function that un-scrambles one block of ciphertext for you. it's giving "reverse card" energy and i'm obsessed 🦋

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✨ NAME ✨

crypto_cipher_decrypt_one — decrypt one block of ciphertext 🔓

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🌸 SYNOPSIS 🌸

void crypto_cipher_decrypt_one (struct crypto_cipher *tfm , u8 *dst ,
const u8 *src );

like, that's the whole signature. no cap, that's it 🫶

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🎀 ARGUMENTS 🎀

• tfm — the cipher handle 💫 (your main character struct, the one that knows which cipher you're running)
• dst — points to the buffer that will be filled with the plaintext ✨ (this is where the readable stuff lands)
• src — buffer holding the ciphertext to be decrypted 💜 (the scrambled input, the before-picture)

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🔥 DESCRIPTION 🔥

Invoke the decryption operation of one block. that's the vibe — one call, one block, decrypted, done 💅

⚠️ real talk though: the caller must ensure that the plaintext and ciphertext buffers are at least one block in size. not me letting you pass a tiny buffer — please don't, that's a whole situation 😭 the function is not gonna size-check for you, so know your block size before you swing.

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🦋 SEE ALSO 🦋

• Kernel file ./include/crypto/internal/cipher.h 📁
• Single Block Cipher API(9)
• crypto_alloc_cipher(9)
• crypto_free_cipher(9)
• crypto_has_cipher(9)
• crypto_cipher_blocksize(9)
• crypto_cipher_setkey(9)
• crypto_cipher_encrypt_one(9) — the other direction, iykyk 👑

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🌸 mwah, that's the page. it lives at ./include/crypto/internal, dated October 2026, and it's part of the Kernel API Manual — go forth and decrypt responsibly, bestie 💖✨