diff options
| author | David S. Miller <davem@davemloft.net> | 2006-09-23 00:17:35 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2006-09-23 00:17:35 +0200 |
| commit | e4bec827feda76d5e7417a2696a75424834d564f (patch) | |
| tree | bd899e0c2fbf7f6dd1d33ce0610d88fc4a8864ee /net/ipv4/esp4.c | |
| parent | [XFRM]: Extract common hashing code into xfrm_hash.[ch] (diff) | |
| download | linux-e4bec827feda76d5e7417a2696a75424834d564f.tar.xz linux-e4bec827feda76d5e7417a2696a75424834d564f.zip | |
[IPSEC] esp: Defer output IV initialization to first use.
First of all, if the xfrm_state only gets used for input
packets this entropy is a complete waste.
Secondly, it is often the case that a configuration loads
many rules (perhaps even dynamically) and they don't all
necessarily ever get used.
This get_random_bytes() call was showing up in the profiles
for xfrm_state inserts which is how I noticed this.
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/esp4.c')
| -rw-r--r-- | net/ipv4/esp4.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c index e87377e1d6b6..13b29360d102 100644 --- a/net/ipv4/esp4.c +++ b/net/ipv4/esp4.c @@ -95,8 +95,13 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb) esph->seq_no = htonl(++x->replay.oseq); xfrm_aevent_doreplay(x); - if (esp->conf.ivlen) + if (esp->conf.ivlen) { + if (unlikely(!esp->conf.ivinitted)) { + get_random_bytes(esp->conf.ivec, esp->conf.ivlen); + esp->conf.ivinitted = 1; + } crypto_blkcipher_set_iv(tfm, esp->conf.ivec, esp->conf.ivlen); + } do { struct scatterlist *sg = &esp->sgbuf[0]; @@ -378,7 +383,7 @@ static int esp_init_state(struct xfrm_state *x) esp->conf.ivec = kmalloc(esp->conf.ivlen, GFP_KERNEL); if (unlikely(esp->conf.ivec == NULL)) goto error; - get_random_bytes(esp->conf.ivec, esp->conf.ivlen); + esp->conf.ivinitted = 0; } if (crypto_blkcipher_setkey(tfm, esp->conf.key, esp->conf.key_len)) goto error; |