cregit-Linux how code gets into the kernel

Release 4.8 net/xfrm/xfrm_replay.c

Directory: net/xfrm
/*
 * xfrm_replay.c - xfrm replay detection, derived from xfrm_state.c.
 *
 * Copyright (C) 2010 secunet Security Networks AG
 * Copyright (C) 2010 Steffen Klassert <steffen.klassert@secunet.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include <linux/export.h>
#include <net/xfrm.h>


u32 xfrm_replay_seqhi(struct xfrm_state *x, __be32 net_seq) { u32 seq, seq_hi, bottom; struct xfrm_replay_state_esn *replay_esn = x->replay_esn; if (!(x->props.flags & XFRM_STATE_ESN)) return 0; seq = ntohl(net_seq); seq_hi = replay_esn->seq_hi; bottom = replay_esn->seq - replay_esn->replay_window + 1; if (likely(replay_esn->seq >= replay_esn->replay_window - 1)) { /* A. same subspace */ if (unlikely(seq < bottom)) seq_hi++; } else { /* B. window spans two subspaces */ if (unlikely(seq >= bottom)) seq_hi--; } return seq_hi; }

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steffen klassertsteffen klassert119100.00%1100.00%
Total119100.00%1100.00%


static void xfrm_replay_notify(struct xfrm_state *x, int event) { struct km_event c; /* we send notify messages in case * 1. we updated on of the sequence numbers, and the seqno difference * is at least x->replay_maxdiff, in this case we also update the * timeout of our timer function * 2. if x->replay_maxage has elapsed since last update, * and there were changes * * The state structure must be locked! */ switch (event) { case XFRM_REPLAY_UPDATE: if (!x->replay_maxdiff || ((x->replay.seq - x->preplay.seq < x->replay_maxdiff) && (x->replay.oseq - x->preplay.oseq < x->replay_maxdiff))) { if (x->xflags & XFRM_TIME_DEFER) event = XFRM_REPLAY_TIMEOUT; else return; } break; case XFRM_REPLAY_TIMEOUT: if (memcmp(&x->replay, &x->preplay, sizeof(struct xfrm_replay_state)) == 0) { x->xflags |= XFRM_TIME_DEFER; return; } break; } memcpy(&x->preplay, &x->replay, sizeof(struct xfrm_replay_state)); c.event = XFRM_MSG_NEWAE; c.data.aevent = event; km_state_notify(x, &c); if (x->replay_maxage && !mod_timer(&x->rtimer, jiffies + x->replay_maxage)) x->xflags &= ~XFRM_TIME_DEFER; }

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steffen klassertsteffen klassert19197.95%150.00%
thomas egererthomas egerer42.05%150.00%
Total195100.00%2100.00%


static int xfrm_replay_overflow(struct xfrm_state *x, struct sk_buff *skb) { int err = 0; struct net *net = xs_net(x); if (x->type->flags & XFRM_TYPE_REPLAY_PROT) { XFRM_SKB_CB(skb)->seq.output.low = ++x->replay.oseq; XFRM_SKB_CB(skb)->seq.output.hi = 0; if (unlikely(x->replay.oseq == 0)) { x->replay.oseq--; xfrm_audit_state_replay_overflow(x, skb); err = -EOVERFLOW; return err; } if (xfrm_aevent_is_on(net)) x->repl->notify(x, XFRM_REPLAY_UPDATE); } return err; }

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steffen klassertsteffen klassert11990.15%150.00%
herbert xuherbert xu139.85%150.00%
Total132100.00%2100.00%


static int xfrm_replay_check(struct xfrm_state *x, struct sk_buff *skb, __be32 net_seq) { u32 diff; u32 seq = ntohl(net_seq); if (!x->props.replay_window) return 0; if (unlikely(seq == 0)) goto err; if (likely(seq > x->replay.seq)) return 0; diff = x->replay.seq - seq; if (diff >= x->props.replay_window) { x->stats.replay_window++; goto err; } if (x->replay.bitmap & (1U << diff)) { x->stats.replay++; goto err; } return 0; err: xfrm_audit_state_replay(x, skb, net_seq); return -EINVAL; }

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steffen klassertsteffen klassert14196.58%266.67%
fan dufan du53.42%133.33%
Total146100.00%3100.00%


static void xfrm_replay_advance(struct xfrm_state *x, __be32 net_seq) { u32 diff; u32 seq = ntohl(net_seq); if (!x->props.replay_window) return; if (seq > x->replay.seq) { diff = seq - x->replay.seq; if (diff < x->props.replay_window) x->replay.bitmap = ((x->replay.bitmap) << diff) | 1; else x->replay.bitmap = 1; x->replay.seq = seq; } else { diff = x->replay.seq - seq; x->replay.bitmap |= (1U << diff); } if (xfrm_aevent_is_on(xs_net(x))) x->repl->notify(x, XFRM_REPLAY_UPDATE); }

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steffen klassertsteffen klassert150100.00%2100.00%
Total150100.00%2100.00%


static int xfrm_replay_overflow_bmp(struct xfrm_state *x, struct sk_buff *skb) { int err = 0; struct xfrm_replay_state_esn *replay_esn = x->replay_esn; struct net *net = xs_net(x); if (x->type->flags & XFRM_TYPE_REPLAY_PROT) { XFRM_SKB_CB(skb)->seq.output.low = ++replay_esn->oseq; XFRM_SKB_CB(skb)->seq.output.hi = 0; if (unlikely(replay_esn->oseq == 0)) { replay_esn->oseq--; xfrm_audit_state_replay_overflow(x, skb); err = -EOVERFLOW; return err; } if (xfrm_aevent_is_on(net)) x->repl->notify(x, XFRM_REPLAY_UPDATE); } return err; }

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steffen klassertsteffen klassert12290.37%150.00%
herbert xuherbert xu139.63%150.00%
Total135100.00%2100.00%


static int xfrm_replay_check_bmp(struct xfrm_state *x, struct sk_buff *skb, __be32 net_seq) { unsigned int bitnr, nr; struct xfrm_replay_state_esn *replay_esn = x->replay_esn; u32 pos; u32 seq = ntohl(net_seq); u32 diff = replay_esn->seq - seq; if (!replay_esn->replay_window) return 0; if (unlikely(seq == 0)) goto err; if (likely(seq > replay_esn->seq)) return 0; if (diff >= replay_esn->replay_window) { x->stats.replay_window++; goto err; } pos = (replay_esn->seq - 1) % replay_esn->replay_window; if (pos >= diff) bitnr = (pos - diff) % replay_esn->replay_window; else bitnr = replay_esn->replay_window - (diff - pos); nr = bitnr >> 5; bitnr = bitnr & 0x1F; if (replay_esn->bmp[nr] & (1U << bitnr)) goto err_replay; return 0; err_replay: x->stats.replay++; err: xfrm_audit_state_replay(x, skb, net_seq); return -EINVAL; }

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steffen klassertsteffen klassert212100.00%3100.00%
Total212100.00%3100.00%


static void xfrm_replay_advance_bmp(struct xfrm_state *x, __be32 net_seq) { unsigned int bitnr, nr, i; u32 diff; struct xfrm_replay_state_esn *replay_esn = x->replay_esn; u32 seq = ntohl(net_seq); u32 pos; if (!replay_esn->replay_window) return; pos = (replay_esn->seq - 1) % replay_esn->replay_window; if (seq > replay_esn->seq) { diff = seq - replay_esn->seq; if (diff < replay_esn->replay_window) { for (i = 1; i < diff; i++) { bitnr = (pos + i) % 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; replay_esn->seq = seq; } else { diff = replay_esn->seq - seq; if (pos >= diff) bitnr = (pos - diff) % replay_esn->replay_window; else bitnr = replay_esn->replay_window - (diff - pos); } nr = bitnr >> 5; bitnr = bitnr & 0x1F; replay_esn->bmp[nr] |= (1U << bitnr); if (xfrm_aevent_is_on(xs_net(x))) x->repl->notify(x, XFRM_REPLAY_UPDATE); }

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steffen klassertsteffen klassert27995.88%480.00%
nickolai zeldovichnickolai zeldovich124.12%120.00%
Total291100.00%5100.00%


static void xfrm_replay_notify_bmp(struct xfrm_state *x, int event) { struct km_event c; struct xfrm_replay_state_esn *replay_esn = x->replay_esn; struct xfrm_replay_state_esn *preplay_esn = x->preplay_esn; /* we send notify messages in case * 1. we updated on of the sequence numbers, and the seqno difference * is at least x->replay_maxdiff, in this case we also update the * timeout of our timer function * 2. if x->replay_maxage has elapsed since last update, * and there were changes * * The state structure must be locked! */ switch (event) { case XFRM_REPLAY_UPDATE: if (!x->replay_maxdiff || ((replay_esn->seq - preplay_esn->seq < x->replay_maxdiff) && (replay_esn->oseq - preplay_esn->oseq < x->replay_maxdiff))) { if (x->xflags & XFRM_TIME_DEFER) event = XFRM_REPLAY_TIMEOUT; else return; } break; case XFRM_REPLAY_TIMEOUT: if (memcmp(x->replay_esn, x->preplay_esn, xfrm_replay_state_esn_len(replay_esn)) == 0) { x->xflags |= XFRM_TIME_DEFER; return; } break; } memcpy(x->preplay_esn, x->replay_esn, xfrm_replay_state_esn_len(replay_esn)); c.event = XFRM_MSG_NEWAE; c.data.aevent = event; km_state_notify(x, &c); if (x->replay_maxage && !mod_timer(&x->rtimer, jiffies + x->replay_maxage)) x->xflags &= ~XFRM_TIME_DEFER; }

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steffen klassertsteffen klassert19597.99%150.00%
thomas egererthomas egerer42.01%150.00%
Total199100.00%2100.00%


static void xfrm_replay_notify_esn(struct xfrm_state *x, int event) { u32 seq_diff, oseq_diff; struct km_event c; struct xfrm_replay_state_esn *replay_esn = x->replay_esn; struct xfrm_replay_state_esn *preplay_esn = x->preplay_esn; /* we send notify messages in case * 1. we updated on of the sequence numbers, and the seqno difference * is at least x->replay_maxdiff, in this case we also update the * timeout of our timer function * 2. if x->replay_maxage has elapsed since last update, * and there were changes * * The state structure must be locked! */ switch (event) { case XFRM_REPLAY_UPDATE: if (x->replay_maxdiff) { if (replay_esn->seq_hi == preplay_esn->seq_hi) seq_diff = replay_esn->seq - preplay_esn->seq; else seq_diff = ~preplay_esn->seq + replay_esn->seq + 1; if (replay_esn->oseq_hi == preplay_esn->oseq_hi) oseq_diff = replay_esn->oseq - preplay_esn->oseq; else oseq_diff = ~preplay_esn->oseq + replay_esn->oseq + 1; if (seq_diff >= x->replay_maxdiff || oseq_diff >= x->replay_maxdiff) break; } if (x->xflags & XFRM_TIME_DEFER) event = XFRM_REPLAY_TIMEOUT; else return; break; case XFRM_REPLAY_TIMEOUT: if (memcmp(x->replay_esn, x->preplay_esn, xfrm_replay_state_esn_len(replay_esn)) == 0) { x->xflags |= XFRM_TIME_DEFER; return; } break; } memcpy(x->preplay_esn, x->replay_esn, xfrm_replay_state_esn_len(replay_esn)); c.event = XFRM_MSG_NEWAE; c.data.aevent = event; km_state_notify(x, &c); if (x->replay_maxage && !mod_timer(&x->rtimer, jiffies + x->replay_maxage)) x->xflags &= ~XFRM_TIME_DEFER; }

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steffen klassertsteffen klassert24495.31%133.33%
mathias krausemathias krause62.34%133.33%
thomas egererthomas egerer62.34%133.33%
Total256100.00%3100.00%


static int xfrm_replay_overflow_esn(struct xfrm_state *x, struct sk_buff *skb) { int err = 0; struct xfrm_replay_state_esn *replay_esn = x->replay_esn; struct net *net = xs_net(x); if (x->type->flags & XFRM_TYPE_REPLAY_PROT) { XFRM_SKB_CB(skb)->seq.output.low = ++replay_esn->oseq; XFRM_SKB_CB(skb)->seq.output.hi = replay_esn->oseq_hi; if (unlikely(replay_esn->oseq == 0)) { XFRM_SKB_CB(skb)->seq.output.hi = ++replay_esn->oseq_hi; if (replay_esn->oseq_hi == 0) { replay_esn->oseq--; replay_esn->oseq_hi--; xfrm_audit_state_replay_overflow(x, skb); err = -EOVERFLOW; return err; } } if (xfrm_aevent_is_on(net)) x->repl->notify(x, XFRM_REPLAY_UPDATE); } return err; }

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steffen klassertsteffen klassert168100.00%3100.00%
Total168100.00%3100.00%


static int xfrm_replay_check_esn(struct xfrm_state *x, struct sk_buff *skb, __be32 net_seq) { unsigned int bitnr, nr; u32 diff; struct xfrm_replay_state_esn *replay_esn = x->replay_esn; u32 pos; u32 seq = ntohl(net_seq); u32 wsize = replay_esn->replay_window; u32 top = replay_esn->seq; u32 bottom = top - wsize + 1; if (!wsize) return 0; if (unlikely(seq == 0 && replay_esn->seq_hi == 0 && (replay_esn->seq < replay_esn->replay_window - 1))) goto err; diff = top - seq; if (likely(top >= wsize - 1)) { /* A. same subspace */ if (likely(seq > top) || seq < bottom) return 0; } else { /* B. window spans two subspaces */ if (likely(seq > top && seq < bottom)) return 0; if (seq >= bottom) diff = ~seq + top + 1; } if (diff >= replay_esn->replay_window) { x->stats.replay_window++; goto err; } pos = (replay_esn->seq - 1) % replay_esn->replay_window; if (pos >= diff) bitnr = (pos - diff) % replay_esn->replay_window; else bitnr = replay_esn->replay_window - (diff - pos); nr = bitnr >> 5; bitnr = bitnr & 0x1F; if (replay_esn->bmp[nr] & (1U << bitnr)) goto err_replay; return 0; err_replay: x->stats.replay++; err: xfrm_audit_state_replay(x, skb, net_seq); return -EINVAL; }

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steffen klassertsteffen klassert302100.00%3100.00%
Total302100.00%3100.00%


static int xfrm_replay_recheck_esn(struct xfrm_state *x, struct sk_buff *skb, __be32 net_seq) { if (unlikely(XFRM_SKB_CB(skb)->seq.input.hi != htonl(xfrm_replay_seqhi(x, net_seq)))) { x->stats.replay_window++; return -EINVAL; } return xfrm_replay_check_esn(x, skb, net_seq); }

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steffen klassertsteffen klassert68100.00%1100.00%
Total68100.00%1100.00%


static void xfrm_replay_advance_esn(struct xfrm_state *x, __be32 net_seq) { unsigned int bitnr, nr, i; int wrap; u32 diff, pos, seq, seq_hi; struct xfrm_replay_state_esn *replay_esn = x->replay_esn; if (!replay_esn->replay_window) return; seq = ntohl(net_seq); pos = (replay_esn->seq - 1) % replay_esn->replay_window; seq_hi = xfrm_replay_seqhi(x, net_seq); wrap = seq_hi - replay_esn->seq_hi; if ((!wrap && seq > replay_esn->seq) || wrap > 0) { if (likely(!wrap)) diff = seq - replay_esn->seq; else diff = ~replay_esn->seq + seq + 1; if (diff < replay_esn->replay_window) { for (i = 1; i < diff; i++) { bitnr = (pos + i) % 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; replay_esn->seq = seq; if (unlikely(wrap > 0)) replay_esn->seq_hi++; } else { diff = replay_esn->seq - seq; if (pos >= diff) bitnr = (pos - diff) % replay_esn->replay_window; else bitnr = replay_esn->replay_window - (diff - pos); } nr = bitnr >> 5; bitnr = bitnr & 0x1F; replay_esn->bmp[nr] |= (1U << bitnr); if (xfrm_aevent_is_on(xs_net(x))) x->repl->notify(x, XFRM_REPLAY_UPDATE); }

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steffen klassertsteffen klassert356100.00%4100.00%
Total356100.00%4100.00%

static struct xfrm_replay xfrm_replay_legacy = { .advance = xfrm_replay_advance, .check = xfrm_replay_check, .recheck = xfrm_replay_check, .notify = xfrm_replay_notify, .overflow = xfrm_replay_overflow, }; static struct xfrm_replay xfrm_replay_bmp = { .advance = xfrm_replay_advance_bmp, .check = xfrm_replay_check_bmp, .recheck = xfrm_replay_check_bmp, .notify = xfrm_replay_notify_bmp, .overflow = xfrm_replay_overflow_bmp, }; static struct xfrm_replay xfrm_replay_esn = { .advance = xfrm_replay_advance_esn, .check = xfrm_replay_check_esn, .recheck = xfrm_replay_recheck_esn, .notify = xfrm_replay_notify_esn, .overflow = xfrm_replay_overflow_esn, };
int xfrm_init_replay(struct xfrm_state *x) { struct xfrm_replay_state_esn *replay_esn = x->replay_esn; if (replay_esn) { if (replay_esn->