From fc1b6d6de2208774efd2a20bf0daddb02d18b1e0 Mon Sep 17 00:00:00 2001 From: Tuong Lien Date: Fri, 8 Nov 2019 12:05:11 +0700 Subject: tipc: introduce TIPC encryption & authentication This commit offers an option to encrypt and authenticate all messaging, including the neighbor discovery messages. The currently most advanced algorithm supported is the AEAD AES-GCM (like IPSec or TLS). All encryption/decryption is done at the bearer layer, just before leaving or after entering TIPC. Supported features: - Encryption & authentication of all TIPC messages (header + data); - Two symmetric-key modes: Cluster and Per-node; - Automatic key switching; - Key-expired revoking (sequence number wrapped); - Lock-free encryption/decryption (RCU); - Asynchronous crypto, Intel AES-NI supported; - Multiple cipher transforms; - Logs & statistics; Two key modes: - Cluster key mode: One single key is used for both TX & RX in all nodes in the cluster. - Per-node key mode: Each nodes in the cluster has one specific TX key. For RX, a node requires its peers' TX key to be able to decrypt the messages from those peers. Key setting from user-space is performed via netlink by a user program (e.g. the iproute2 'tipc' tool). Internal key state machine: Attach Align(RX) +-+ +-+ | V | V +---------+ Attach +---------+ | IDLE |---------------->| PENDING |(user = 0) +---------+ +---------+ A A Switch| A | | | | | | Free(switch/revoked) | | (Free)| +----------------------+ | |Timeout | (TX) | | |(RX) | | | | | | v | +---------+ Switch +---------+ | PASSIVE |<----------------| ACTIVE | +---------+ (RX) +---------+ (user = 1) (user >= 1) The number of TFMs is 10 by default and can be changed via the procfs 'net/tipc/max_tfms'. At this moment, as for simplicity, this file is also used to print the crypto statistics at runtime: echo 0xfff1 > /proc/sys/net/tipc/max_tfms The patch defines a new TIPC version (v7) for the encryption message (- backward compatibility as well). The message is basically encapsulated as follows: +----------------------------------------------------------+ | TIPCv7 encryption | Original TIPCv2 | Authentication | | header | packet (encrypted) | Tag | +----------------------------------------------------------+ The throughput is about ~40% for small messages (compared with non- encryption) and ~9% for large messages. With the support from hardware crypto i.e. the Intel AES-NI CPU instructions, the throughput increases upto ~85% for small messages and ~55% for large messages. By default, the new feature is inactive (i.e. no encryption) until user sets a key for TIPC. There is however also a new option - "TIPC_CRYPTO" in the kernel configuration to enable/disable the new code when needed. MAINTAINERS | add two new files 'crypto.h' & 'crypto.c' in tipc Acked-by: Ying Xue Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller --- net/tipc/msg.h | 46 ++++++++++++++++++++++++++++++++++++---------- 1 file changed, 36 insertions(+), 10 deletions(-) (limited to 'net/tipc/msg.h') diff --git a/net/tipc/msg.h b/net/tipc/msg.h index 14697e6c995e..6d466ebdb64f 100644 --- a/net/tipc/msg.h +++ b/net/tipc/msg.h @@ -102,16 +102,42 @@ struct plist; #define TIPC_MEDIA_INFO_OFFSET 5 struct tipc_skb_cb { - struct sk_buff *tail; - unsigned long nxt_retr; - unsigned long retr_stamp; - u32 bytes_read; - u32 orig_member; - u16 chain_imp; - u16 ackers; - u16 retr_cnt; - bool validated; -}; + union { + struct { + struct sk_buff *tail; + unsigned long nxt_retr; + unsigned long retr_stamp; + u32 bytes_read; + u32 orig_member; + u16 chain_imp; + u16 ackers; + u16 retr_cnt; + } __packed; +#ifdef CONFIG_TIPC_CRYPTO + struct { + struct tipc_crypto *rx; + struct tipc_aead *last; + u8 recurs; + } tx_clone_ctx __packed; +#endif + } __packed; + union { + struct { + u8 validated:1; +#ifdef CONFIG_TIPC_CRYPTO + u8 encrypted:1; + u8 decrypted:1; + u8 probe:1; + u8 tx_clone_deferred:1; +#endif + }; + u8 flags; + }; + u8 reserved; +#ifdef CONFIG_TIPC_CRYPTO + void *crypto_ctx; +#endif +} __packed; #define TIPC_SKB_CB(__skb) ((struct tipc_skb_cb *)&((__skb)->cb[0])) -- cgit v1.2.3