Re: [PATCH v2 3/5] crypto/net/tcp: Use crypto_pool for TCP-MD5

[Dmitry Safonov <dima@arista.com>]

On 1/7/23 02:05, Jakub Kicinski wrote:
> On Tue,  3 Jan 2023 18:42:55 +0000 Dmitry Safonov wrote:
>> Use crypto_pool API that was designed with tcp_md5sig_pool in mind.
>> The conversion to use crypto_pool will allow:
>> - to reuse ahash_request(s) for different users
>> - to allocate only one per-CPU scratch buffer rather than a new one for
>>   each user
>> - to have a common API for net/ users that need ahash on RX/TX fast path
> 
>>  config TCP_MD5SIG
>>  	bool "TCP: MD5 Signature Option support (RFC2385)"
>> -	select CRYPTO
>> +	select CRYPTO_POOL
> 
> Are you sure we don't need to select CRYPTO any more?
> select does not resolve dependencies.

Yeah, stumbled into it when I was rebasing TCP-AO patches on the top:
they select both and I think you're right that it still needs to select
CRYPTO here as well (noticed only after sending v2).

> 
>>  	select CRYPTO_MD5
>>  	help
>>  	  RFC2385 specifies a method of giving MD5 protection to TCP sessions.
> 
>> @@ -749,29 +746,27 @@ static int tcp_v6_md5_hash_skb(char *md5_hash,
>>  		daddr = &ip6h->daddr;
>>  	}
>>  
>> -	hp = tcp_get_md5sig_pool();
>> -	if (!hp)
>> +	if (crypto_pool_get(tcp_md5_crypto_pool_id, (struct crypto_pool *)&hp))
> 
> &hp.base ? To avoid the cast

Oh, that's nice, will do!

Thanks,
          Dmitry