On 20/11/2023 20:13, Alexei Starovoitov wrote:
On Sun, Nov 19, 2023 at 4:22 PM Vadim Fedorenko
<vadim.fedorenko@xxxxxxxxx> wrote:
On 19.11.2023 16:56, Alexei Starovoitov wrote:
On Sat, Nov 18, 2023 at 3:46 PM Vadim Fedorenko
<vadim.fedorenko@xxxxxxxxx> wrote:
On 18/11/2023 18:35, Alexei Starovoitov wrote:
On Sat, Nov 18, 2023 at 3:32 PM Vadim Fedorenko
<vadim.fedorenko@xxxxxxxxx> wrote:
On 18/11/2023 18:23, Alexei Starovoitov wrote:
On Sat, Nov 18, 2023 at 2:55 PM Vadim Fedorenko <vadfed@xxxxxxxx> wrote:
+/**
+ * struct bpf_crypto_lskcipher_ctx - refcounted BPF sync skcipher context structure
+ * @tfm: The pointer to crypto_sync_skcipher struct.
+ * @rcu: The RCU head used to free the crypto context with RCU safety.
+ * @usage: Object reference counter. When the refcount goes to 0, the
+ * memory is released back to the BPF allocator, which provides
+ * RCU safety.
+ */
+struct bpf_crypto_lskcipher_ctx {
+ struct crypto_lskcipher *tfm;
+ struct rcu_head rcu;
+ refcount_t usage;
+};
+
+__bpf_kfunc_start_defs();
+
+/**
+ * bpf_crypto_lskcipher_ctx_create() - Create a mutable BPF crypto context.
Let's drop 'lskcipher' from the kfunc names and ctx struct.
bpf users don't need to know the internal implementation details.
bpf_crypto_encrypt/decrypt() is clear enough.
The only reason I added it was the existence of AEAD subset of crypto
API. And this subset can also be implemented in bpf later, and there
will be inconsistency in naming then if we add aead in future names.
WDYT?
You mean future async apis ? Just bpf_crypto_encrypt_async() ?
Well, not only async. It's about Authenticated Encryption With
Associated Data (AEAD) Cipher API defined in crypto/aead.h. It's
ciphers with additional hmac function, like
'authenc(hmac(sha256),cbc(aes))'. It has very similar API with only
difference of having Authenticated data in the encrypted block.
and ? I'm not following what you're trying to say.
Where is the inconsistency ?
My point again is that lskcipher vs skcipher vs foo is an implementation
detail that shouldn't be exposed in the name.
Well, I was trying to follow crypto subsystem naming. It might be easier for
users to understand what part of crypto API is supported by BPF kfuncs.
At the same we can agree that current implementation will be used for simple
buffer encryption/decryption and any further implementations will have additions
in the name of functions (like
bpf_crypto_aead_crypt/bpf_crypto_shash_final/bpf_crypto_scomp_compress).
It will be slightly inconsistent, but we will have to expose some implementation
details unfortunately. If you are ok with this way, I'm ok to implement it.
but shash vs scomp is the name of the algo ? Didn't you use it as
the 1st arg to bpf_crypto_create() ?
Take a look at AF_ALG. It's able to express all kinds of cryptos
through the same socket abstraction without creating a new name for
every algo. Everything is read/write through the socket fd.
In our case it will be bpf_crypto_encrypt/decrypt() kfuncs.
Ok, I got the idea. I'll make v6 more general, like AF_ALG, but it will
support only one type (skcipher) for now. Thanks!
