From: Steffen Klassert Subject: [RFC v2 PATCH 9/9] xfrm: Add user interface for esn and big anti-replay windows Date: Tue, 8 Mar 2011 11:10:27 +0100 Message-ID: <20110308101027.GK31402@secunet.com> References: <20110308100407.GB31402@secunet.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Alex Badea , Andreas Gruenbacher , netdev@vger.kernel.org, linux-crypto@vger.kernel.org To: Herbert Xu , David Miller Return-path: Content-Disposition: inline In-Reply-To: <20110308100407.GB31402@secunet.com> Sender: netdev-owner@vger.kernel.org List-Id: linux-crypto.vger.kernel.org This patch adds a netlink based user interface to configure esn and big anti-replay windows. The new netlink attribute XFRMA_REPLAY_ESN_VAL is used to configure the new implementation. If the XFRM_STATE_ESN flag is set, we use esn and support for big anti-replay windows for the configured state. If this flag is not set we use the new implementation with 32 bit sequence numbers. A big anti-replay window can be configured in this case anyway. Signed-off-by: Steffen Klassert --- net/xfrm/xfrm_state.c | 2 + net/xfrm/xfrm_user.c | 99 ++++++++++++++++++++++++++++++++++++++++++------- 2 files changed, 87 insertions(+), 14 deletions(-) diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c index 104cddf..47e37bf 100644 --- a/net/xfrm/xfrm_state.c +++ b/net/xfrm/xfrm_state.c @@ -356,6 +356,8 @@ static void xfrm_state_gc_destroy(struct xfrm_state *x) kfree(x->calg); kfree(x->encap); kfree(x->coaddr); + kfree(x->replay_esn); + kfree(x->preplay_esn); if (x->inner_mode) xfrm_put_mode(x->inner_mode); if (x->inner_mode_iaf) diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index f7b3c85..706385a 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -119,6 +119,19 @@ static inline int verify_sec_ctx_len(struct nlattr **attrs) return 0; } +static inline int verify_replay(struct xfrm_usersa_info *p, + struct nlattr **attrs) +{ + struct nlattr *rt = attrs[XFRMA_REPLAY_ESN_VAL]; + + if (!rt) + return 0; + + if (p->replay_window != 0) + return -EINVAL; + + return 0; +} static int verify_newsa_info(struct xfrm_usersa_info *p, struct nlattr **attrs) @@ -214,6 +227,8 @@ static int verify_newsa_info(struct xfrm_usersa_info *p, goto out; if ((err = verify_sec_ctx_len(attrs))) goto out; + if ((err = verify_replay(p, attrs))) + goto out; err = -EINVAL; switch (p->mode) { @@ -345,6 +360,33 @@ static int attach_aead(struct xfrm_algo_aead **algpp, u8 *props, return 0; } +static int xfrm_alloc_replay_state_esn(struct xfrm_replay_state_esn **replay_esn, + struct xfrm_replay_state_esn **preplay_esn, + struct nlattr *rta) +{ + struct xfrm_replay_state_esn *p, *pp, *up; + + if (!rta) + return 0; + + up = nla_data(rta); + + p = kmemdup(up, xfrm_replay_state_esn_len(up), GFP_KERNEL); + if (!p) + return -ENOMEM; + + pp = kmemdup(up, xfrm_replay_state_esn_len(up), GFP_KERNEL); + if (!pp) { + kfree(p); + return -ENOMEM; + } + + *replay_esn = p; + *preplay_esn = pp; + + return 0; +} + static inline int xfrm_user_sec_ctx_size(struct xfrm_sec_ctx *xfrm_ctx) { int len = 0; @@ -380,10 +422,20 @@ static void copy_from_user_state(struct xfrm_state *x, struct xfrm_usersa_info * static void xfrm_update_ae_params(struct xfrm_state *x, struct nlattr **attrs) { struct nlattr *rp = attrs[XFRMA_REPLAY_VAL]; + struct nlattr *re = attrs[XFRMA_REPLAY_ESN_VAL]; struct nlattr *lt = attrs[XFRMA_LTIME_VAL]; struct nlattr *et = attrs[XFRMA_ETIMER_THRESH]; struct nlattr *rt = attrs[XFRMA_REPLAY_THRESH]; + if (re) { + struct xfrm_replay_state_esn *replay_esn; + replay_esn = nla_data(re); + memcpy(x->replay_esn, replay_esn, + xfrm_replay_state_esn_len(replay_esn)); + memcpy(x->preplay_esn, replay_esn, + xfrm_replay_state_esn_len(replay_esn)); + } + if (rp) { struct xfrm_replay_state *replay; replay = nla_data(rp); @@ -467,13 +519,14 @@ static struct xfrm_state *xfrm_state_construct(struct net *net, security_xfrm_state_alloc(x, nla_data(attrs[XFRMA_SEC_CTX]))) goto error; + if ((err = xfrm_alloc_replay_state_esn(&x->replay_esn, &x->preplay_esn, + attrs[XFRMA_REPLAY_ESN_VAL]))) + goto error; + x->km.seq = p->seq; x->replay_maxdiff = net->xfrm.sysctl_aevent_rseqth; /* sysctl_xfrm_aevent_etime is in 100ms units */ x->replay_maxage = (net->xfrm.sysctl_aevent_etime*HZ)/XFRM_AE_ETH_M; - x->preplay.bitmap = 0; - x->preplay.seq = x->replay.seq+x->replay_maxdiff; - x->preplay.oseq = x->replay.oseq +x->replay_maxdiff; if ((err = xfrm_init_replay(x))) goto error; @@ -709,6 +762,10 @@ static int copy_to_user_state_extra(struct xfrm_state *x, if (xfrm_mark_put(skb, &x->mark)) goto nla_put_failure; + if (x->replay_esn) + NLA_PUT(skb, XFRMA_REPLAY_ESN_VAL, + xfrm_replay_state_esn_len(x->replay_esn), x->replay_esn); + if (x->security && copy_sec_ctx(x->security, skb) < 0) goto nla_put_failure; @@ -1578,10 +1635,14 @@ static int xfrm_flush_sa(struct sk_buff *skb, struct nlmsghdr *nlh, return 0; } -static inline size_t xfrm_aevent_msgsize(void) +static inline size_t xfrm_aevent_msgsize(struct xfrm_state *x) { + size_t replay_size = x->replay_esn ? + xfrm_replay_state_esn_len(x->replay_esn) : + sizeof(struct xfrm_replay_state); + return NLMSG_ALIGN(sizeof(struct xfrm_aevent_id)) - + nla_total_size(sizeof(struct xfrm_replay_state)) + + nla_total_size(replay_size) + nla_total_size(sizeof(struct xfrm_lifetime_cur)) + nla_total_size(sizeof(struct xfrm_mark)) + nla_total_size(4) /* XFRM_AE_RTHR */ @@ -1606,7 +1667,13 @@ static int build_aevent(struct sk_buff *skb, struct xfrm_state *x, const struct id->reqid = x->props.reqid; id->flags = c->data.aevent; - NLA_PUT(skb, XFRMA_REPLAY_VAL, sizeof(x->replay), &x->replay); + if (x->replay_esn) + NLA_PUT(skb, XFRMA_REPLAY_ESN_VAL, + xfrm_replay_state_esn_len(x->replay_esn), + x->replay_esn); + else + NLA_PUT(skb, XFRMA_REPLAY_VAL, sizeof(x->replay), &x->replay); + NLA_PUT(skb, XFRMA_LTIME_VAL, sizeof(x->curlft), &x->curlft); if (id->flags & XFRM_AE_RTHR) @@ -1639,16 +1706,16 @@ static int xfrm_get_ae(struct sk_buff *skb, struct nlmsghdr *nlh, struct xfrm_aevent_id *p = nlmsg_data(nlh); struct xfrm_usersa_id *id = &p->sa_id; - r_skb = nlmsg_new(xfrm_aevent_msgsize(), GFP_ATOMIC); - if (r_skb == NULL) - return -ENOMEM; - mark = xfrm_mark_get(attrs, &m); x = xfrm_state_lookup(net, mark, &id->daddr, id->spi, id->proto, id->family); - if (x == NULL) { - kfree_skb(r_skb); + if (x == NULL) return -ESRCH; + + r_skb = nlmsg_new(xfrm_aevent_msgsize(x), GFP_ATOMIC); + if (r_skb == NULL) { + xfrm_state_put(x); + return -ENOMEM; } /* @@ -1680,9 +1747,10 @@ static int xfrm_new_ae(struct sk_buff *skb, struct nlmsghdr *nlh, struct xfrm_mark m; struct xfrm_aevent_id *p = nlmsg_data(nlh); struct nlattr *rp = attrs[XFRMA_REPLAY_VAL]; + struct nlattr *re = attrs[XFRMA_REPLAY_ESN_VAL]; struct nlattr *lt = attrs[XFRMA_LTIME_VAL]; - if (!lt && !rp) + if (!lt && !rp && !re) return err; /* pedantic mode - thou shalt sayeth replaceth */ @@ -2147,6 +2215,7 @@ static const struct nla_policy xfrma_policy[XFRMA_MAX+1] = { [XFRMA_KMADDRESS] = { .len = sizeof(struct xfrm_user_kmaddress) }, [XFRMA_MARK] = { .len = sizeof(struct xfrm_mark) }, [XFRMA_TFCPAD] = { .type = NLA_U32 }, + [XFRMA_REPLAY_ESN_VAL] = { .len = sizeof(struct xfrm_replay_state_esn) }, }; static struct xfrm_link { @@ -2274,7 +2343,7 @@ static int xfrm_aevent_state_notify(struct xfrm_state *x, const struct km_event struct net *net = xs_net(x); struct sk_buff *skb; - skb = nlmsg_new(xfrm_aevent_msgsize(), GFP_ATOMIC); + skb = nlmsg_new(xfrm_aevent_msgsize(x), GFP_ATOMIC); if (skb == NULL) return -ENOMEM; @@ -2328,6 +2397,8 @@ static inline size_t xfrm_sa_len(struct xfrm_state *x) l += nla_total_size(sizeof(*x->encap)); if (x->tfcpad) l += nla_total_size(sizeof(x->tfcpad)); + if (x->replay_esn) + l += nla_total_size(xfrm_replay_state_esn_len(x->replay_esn)); if (x->security) l += nla_total_size(sizeof(struct xfrm_user_sec_ctx) + x->security->ctx_len); -- 1.7.0.4