From 1d9743745bf5ba30b57986d8da33c4fa072c355b Mon Sep 17 00:00:00 2001 From: Steffen Klassert Date: Tue, 11 Oct 2011 01:58:37 +0000 Subject: [PATCH] xfrm: Simplify the replay check and advance functions The replay check and replay advance functions had some code duplications. This patch removes the duplications. Signed-off-by: Steffen Klassert Signed-off-by: David S. Miller --- net/xfrm/xfrm_replay.c | 98 +++++++++++++++--------------------------- 1 file changed, 34 insertions(+), 64 deletions(-) diff --git a/net/xfrm/xfrm_replay.c b/net/xfrm/xfrm_replay.c index b11ea692bd7d..6ca357406ea8 100644 --- a/net/xfrm/xfrm_replay.c +++ b/net/xfrm/xfrm_replay.c @@ -203,8 +203,6 @@ static int xfrm_replay_check_bmp(struct xfrm_state *x, if (!replay_esn->replay_window) return 0; - pos = (replay_esn->seq - 1) % replay_esn->replay_window; - if (unlikely(seq == 0)) goto err; @@ -216,19 +214,18 @@ static int xfrm_replay_check_bmp(struct xfrm_state *x, goto err; } - if (pos >= diff) { + pos = (replay_esn->seq - 1) % replay_esn->replay_window; + + if (pos >= diff) bitnr = (pos - diff) % replay_esn->replay_window; - nr = bitnr >> 5; - bitnr = bitnr & 0x1F; - if (replay_esn->bmp[nr] & (1U << bitnr)) - goto err_replay; - } else { + else bitnr = replay_esn->replay_window - (diff - pos); - nr = bitnr >> 5; - bitnr = bitnr & 0x1F; - if (replay_esn->bmp[nr] & (1U << bitnr)) - goto err_replay; - } + + nr = bitnr >> 5; + bitnr = bitnr & 0x1F; + if (replay_esn->bmp[nr] & (1U << bitnr)) + goto err_replay; + return 0; err_replay: @@ -259,39 +256,27 @@ static void xfrm_replay_advance_bmp(struct xfrm_state *x, __be32 net_seq) bitnr = bitnr & 0x1F; replay_esn->bmp[nr] &= ~(1U << bitnr); } - - bitnr = (pos + diff) % replay_esn->replay_window; - nr = bitnr >> 5; - bitnr = bitnr & 0x1F; - replay_esn->bmp[nr] |= (1U << bitnr); } else { nr = (replay_esn->replay_window - 1) >> 5; for (i = 0; i <= nr; i++) replay_esn->bmp[i] = 0; - - bitnr = (pos + diff) % replay_esn->replay_window; - nr = bitnr >> 5; - bitnr = bitnr & 0x1F; - replay_esn->bmp[nr] |= (1U << bitnr); } + bitnr = (pos + diff) % replay_esn->replay_window; replay_esn->seq = seq; } else { diff = replay_esn->seq - seq; - if (pos >= diff) { + if (pos >= diff) bitnr = (pos - diff) % replay_esn->replay_window; - nr = bitnr >> 5; - bitnr = bitnr & 0x1F; - replay_esn->bmp[nr] |= (1U << bitnr); - } else { + else bitnr = replay_esn->replay_window - (diff - pos); - nr = bitnr >> 5; - bitnr = bitnr & 0x1F; - replay_esn->bmp[nr] |= (1U << bitnr); - } } + nr = bitnr >> 5; + bitnr = bitnr & 0x1F; + replay_esn->bmp[nr] |= (1U << bitnr); + if (xfrm_aevent_is_on(xs_net(x))) xfrm_replay_notify(x, XFRM_REPLAY_UPDATE); } @@ -390,8 +375,6 @@ static int xfrm_replay_check_esn(struct xfrm_state *x, if (!wsize) return 0; - pos = (replay_esn->seq - 1) % replay_esn->replay_window; - if (unlikely(seq == 0 && replay_esn->seq_hi == 0 && (replay_esn->seq < replay_esn->replay_window - 1))) goto err; @@ -415,19 +398,18 @@ static int xfrm_replay_check_esn(struct xfrm_state *x, goto err; } - if (pos >= diff) { + pos = (replay_esn->seq - 1) % replay_esn->replay_window; + + if (pos >= diff) bitnr = (pos - diff) % replay_esn->replay_window; - nr = bitnr >> 5; - bitnr = bitnr & 0x1F; - if (replay_esn->bmp[nr] & (1U << bitnr)) - goto err_replay; - } else { + else bitnr = replay_esn->replay_window - (diff - pos); - nr = bitnr >> 5; - bitnr = bitnr & 0x1F; - if (replay_esn->bmp[nr] & (1U << bitnr)) - goto err_replay; - } + + nr = bitnr >> 5; + bitnr = bitnr & 0x1F; + if (replay_esn->bmp[nr] & (1U << bitnr)) + goto err_replay; + return 0; err_replay: @@ -465,22 +447,13 @@ static void xfrm_replay_advance_esn(struct xfrm_state *x, __be32 net_seq) bitnr = bitnr & 0x1F; replay_esn->bmp[nr] &= ~(1U << bitnr); } - - bitnr = (pos + diff) % replay_esn->replay_window; - nr = bitnr >> 5; - bitnr = bitnr & 0x1F; - replay_esn->bmp[nr] |= (1U << bitnr); } else { nr = (replay_esn->replay_window - 1) >> 5; for (i = 0; i <= nr; i++) replay_esn->bmp[i] = 0; - - bitnr = (pos + diff) % replay_esn->replay_window; - nr = bitnr >> 5; - bitnr = bitnr & 0x1F; - replay_esn->bmp[nr] |= (1U << bitnr); } + bitnr = (pos + diff) % replay_esn->replay_window; replay_esn->seq = seq; if (unlikely(wrap > 0)) @@ -488,19 +461,16 @@ static void xfrm_replay_advance_esn(struct xfrm_state *x, __be32 net_seq) } else { diff = replay_esn->seq - seq; - if (pos >= diff) { + if (pos >= diff) bitnr = (pos - diff) % replay_esn->replay_window; - nr = bitnr >> 5; - bitnr = bitnr & 0x1F; - replay_esn->bmp[nr] |= (1U << bitnr); - } else { + else bitnr = replay_esn->replay_window - (diff - pos); - nr = bitnr >> 5; - bitnr = bitnr & 0x1F; - replay_esn->bmp[nr] |= (1U << bitnr); - } } + nr = bitnr >> 5; + bitnr = bitnr & 0x1F; + replay_esn->bmp[nr] |= (1U << bitnr); + if (xfrm_aevent_is_on(xs_net(x))) xfrm_replay_notify(x, XFRM_REPLAY_UPDATE); } -- 2.20.1