STRUCT KPP_ALG(9)

💅 struct kpp_alg(9) 💅

okay so welcome to the Kernel API Manual, bestie — we're talking struct kpp_alg, which is literally the blueprint for generic key-agreement protocol primitives. no cap, it's the whole vibe behind how the kernel does key agreement, and once you get it you're gonna slay.

✨ NAME ✨

struct kpp_alg — generic key-agreement protocol primitives 🫶

🌸 SYNOPSIS 🌸

struct kpp_alg {
    int (*set_secret)(struct crypto_kpp *tfm, const void *buffer,
unsigned int len);
    int (*generate_public_key)(struct kpp_request *req);
    int (*compute_shared_secret)(struct kpp_request *req);
    unsigned int (*max_size)(struct crypto_kpp *tfm);
    int (*init)(struct crypto_kpp *tfm);
    void (*exit)(struct crypto_kpp *tfm);
    struct crypto_alg base;
 };

🎀 MEMBERS 🎀

like, here's the whole cast of function pointers — each one is a main character in their own right:

• set_secret — this one calls the protocol-specific function that stores the secret private key plus its parameters. the implementation is the one that knows how to decode buffer, so don't come for it 💅
• generate_public_key — generates the public key that gets sent to the counterpart. ok and listen: if there's an error where the output isn't big enough, req->dst_len gets updated to the size required. noted. 🦋
• compute_shared_secret — computes the shared secret exactly as the algorithm defines it, and the result goes right back to the user. same deal as above: if it errors because the output is too small, req->dst_len gets updated to the size required. 💖
• max_size — returns the size of the output buffer. short and iconic.
• init — initializes the object. this gets called only once, at instantiation time — that's the moment, bestie. it's for when the cryptographic hardware needs to be initialized, and any software fallback should be put in place right here. 🧚
• exit — undoes everything init did. the cleanup era. 🫧
• base — the common crypto API algorithm data structure. the foundation, the moment, the baseline.

🌈 SEE ALSO 🌈

• kernel file ./include/crypto/kpp.h
• struct kpp_request(9)
• struct crypto_kpp(9)
• Generic Key-agreement Protocol Primitives API(9)
• crypto_alloc_kpp(9)
• crypto_free_kpp(9)
• kpp_request_alloc(9)
• kpp_request_free(9)
• kpp_request_set_callback(9)
• kpp_request_set_input(9)
• kpp_request_set_output(9)
• struct kpp_secret(9)
• crypto_kpp_set_secret(9)
• crypto_kpp_generate_public_key(9)
• crypto_kpp_compute_shared_secret(9)
• crypto_kpp_maxsize(9)

💀 real talk: this page ships from ./include/crypto and it's dated October 2026 — so yeah, future-coded. anyway bestie, go read the source, ily, bye! 👑✨🎀