diff options
| author | David Howells <dhowells@redhat.com> | 2016-09-02 22:39:45 +0100 |
|---|---|---|
| committer | David Howells <dhowells@redhat.com> | 2016-09-04 21:41:39 +0100 |
| commit | 5f2d9c44389e7cd9fe192570f6f20199bc861eb8 (patch) | |
| tree | 1339480e8cf3b2efaa3f1543e7504e3eb0602408 | |
| parent | af338a9ea60acc6337fe9fcdcf664aec2520e541 (diff) | |
| download | linux-5f2d9c44389e7cd9fe192570f6f20199bc861eb8.tar.bz2 | |
rxrpc: Randomise epoch and starting client conn ID values
Create a random epoch value rather than a time-based one on startup and set
the top bit to indicate that this is the case.
Also create a random starting client connection ID value. This will be
incremented from here as new client connections are created.
Signed-off-by: David Howells <dhowells@redhat.com>
| -rw-r--r-- | include/rxrpc/packet.h | 1 | ||||
| -rw-r--r-- | net/rxrpc/af_rxrpc.c | 9 |
2 files changed, 9 insertions, 1 deletions
diff --git a/include/rxrpc/packet.h b/include/rxrpc/packet.h index b2017440b765..3c6128e1fdbe 100644 --- a/include/rxrpc/packet.h +++ b/include/rxrpc/packet.h @@ -24,6 +24,7 @@ typedef __be32 rxrpc_serial_net_t; /* on-the-wire Rx message serial number */ */ struct rxrpc_wire_header { __be32 epoch; /* client boot timestamp */ +#define RXRPC_RANDOM_EPOCH 0x80000000 /* Random if set, date-based if not */ __be32 cid; /* connection and channel ID */ #define RXRPC_MAXCALLS 4 /* max active calls per conn */ diff --git a/net/rxrpc/af_rxrpc.c b/net/rxrpc/af_rxrpc.c index 32d544995dda..b66a9e6f8d04 100644 --- a/net/rxrpc/af_rxrpc.c +++ b/net/rxrpc/af_rxrpc.c @@ -16,6 +16,7 @@ #include <linux/net.h> #include <linux/slab.h> #include <linux/skbuff.h> +#include <linux/random.h> #include <linux/poll.h> #include <linux/proc_fs.h> #include <linux/key-type.h> @@ -700,7 +701,13 @@ static int __init af_rxrpc_init(void) BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > FIELD_SIZEOF(struct sk_buff, cb)); - rxrpc_epoch = get_seconds(); + get_random_bytes(&rxrpc_epoch, sizeof(rxrpc_epoch)); + rxrpc_epoch |= RXRPC_RANDOM_EPOCH; + get_random_bytes(&rxrpc_client_conn_ids.cur, + sizeof(rxrpc_client_conn_ids.cur)); + rxrpc_client_conn_ids.cur &= 0x3fffffff; + if (rxrpc_client_conn_ids.cur == 0) + rxrpc_client_conn_ids.cur = 1; ret = -ENOMEM; rxrpc_call_jar = kmem_cache_create( |