On Wed, 5 Jun 2019 17:39:23 +0200, Davide Caratti wrote:
> When an application configures kernel TLS on top of a TCP socket, it's
> now possible for inet_diag_handler to collect information regarding the
> protocol version and the cipher, in case INET_DIAG_INFO is requested.
>
> Signed-off-by: Davide Caratti <dcara...@redhat.com>
> ---
> include/uapi/linux/inet_diag.h | 1 +
> include/uapi/linux/tls.h | 8 +++++++
> net/tls/tls_main.c | 43 ++++++++++++++++++++++++++++++++++
> 3 files changed, 52 insertions(+)
>
> diff --git a/include/uapi/linux/inet_diag.h b/include/uapi/linux/inet_diag.h
> index 844133de3212..92208535c096 100644
> --- a/include/uapi/linux/inet_diag.h
> +++ b/include/uapi/linux/inet_diag.h
> @@ -161,6 +161,7 @@ enum {
>
> enum {
> ULP_INFO_NAME,
> + ULP_INFO_TLS,
> __ULP_INFO_MAX,
> };
>
> diff --git a/include/uapi/linux/tls.h b/include/uapi/linux/tls.h
> index 5b9c26753e46..442348bd2e54 100644
> --- a/include/uapi/linux/tls.h
> +++ b/include/uapi/linux/tls.h
> @@ -109,4 +109,12 @@ struct tls12_crypto_info_aes_ccm_128 {
> unsigned char rec_seq[TLS_CIPHER_AES_CCM_128_REC_SEQ_SIZE];
> };
>
> +enum {
USPEC
> + TLS_INFO_VERSION,
> + TLS_INFO_CIPHER,
We need some indication of the directions in which kTLS is active
(none, rx, tx, rx/tx).
Also perhaps could you add TLS_SW vs TLS_HW etc. ? :)
> + __TLS_INFO_MAX,
> +};
> +
Traditionally we put no new line between enum and the max define.
> +#define TLS_INFO_MAX (__TLS_INFO_MAX - 1)
> +
> #endif /* _UAPI_LINUX_TLS_H */
> diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c
> index fc81ae18cc44..14597526981c 100644
> --- a/net/tls/tls_main.c
> +++ b/net/tls/tls_main.c
> @@ -39,6 +39,7 @@
> #include <linux/netdevice.h>
> #include <linux/sched/signal.h>
> #include <linux/inetdevice.h>
> +#include <linux/inet_diag.h>
>
> #include <net/tls.h>
>
> @@ -798,6 +799,46 @@ static int tls_init(struct sock *sk)
> return rc;
> }
>
> +static int tls_get_info(struct sock *sk, struct sk_buff *skb)
> +{
> + struct tls_context *ctx = tls_get_ctx(sk);
> + struct nlattr *start = 0;
Hm.. NULL? Does this not give you a warning?
> + int err = 0;
There should be no need to init this.
> + if (sk->sk_state != TCP_ESTABLISHED)
Hmm.. why this check? We never clean up the state once installed until
the socket dies completely (currently, pending John's unhash work).
> + goto end;
Please don't do this, just return 0; here.
> + start = nla_nest_start_noflag(skb, ULP_INFO_TLS);
> + if (!start) {
> + err = -EMSGSIZE;
> + goto nla_failure;
return -EMSGSIZE;
> + }
> + err = nla_put_u16(skb, TLS_INFO_VERSION, ctx->prot_info.version);
> + if (err < 0)
> + goto nla_failure;
> + err = nla_put_u16(skb, TLS_INFO_CIPHER, ctx->prot_info.cipher_type);
> + if (err < 0)
> + goto nla_failure;
> + nla_nest_end(skb, start);
> +end:
> + return err;
return 0;
> +nla_failure:
> + nla_nest_cancel(skb, start);
> + goto end;
return err;
> +}
> +
> +static size_t tls_get_info_size(struct sock *sk)
> +{
> + size_t size = 0;
> +
> + if (sk->sk_state != TCP_ESTABLISHED)
> + return size;
> +
> + size += nla_total_size(0) /* ULP_INFO_TLS */
> + + nla_total_size(sizeof(__u16)) /* TLS_INFO_VERSION */
> + + nla_total_size(sizeof(__u16)); /* TLS_INFO_CIPHER */
> + return size;
> +}
Same comments as on patch 1 and above.
> void tls_register_device(struct tls_device *device)
> {
> spin_lock_bh(&device_spinlock);
Thanks for working on this, it was on my todo list! :)
