aboutsummaryrefslogtreecommitdiffstats
path: root/net/ipv4/ip_fragment.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/ipv4/ip_fragment.c')
-rw-r--r--net/ipv4/ip_fragment.c253
1 files changed, 114 insertions, 139 deletions
diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c
index bbf1b94942c0..994fa70a910f 100644
--- a/net/ipv4/ip_fragment.c
+++ b/net/ipv4/ip_fragment.c
@@ -57,27 +57,13 @@
*/
static const char ip_frag_cache_name[] = "ip4-frags";
-struct ipfrag_skb_cb
-{
- struct inet_skb_parm h;
- int offset;
-};
-
-#define FRAG_CB(skb) ((struct ipfrag_skb_cb *)((skb)->cb))
-
/* Describe an entry in the "incomplete datagrams" queue. */
struct ipq {
struct inet_frag_queue q;
- u32 user;
- __be32 saddr;
- __be32 daddr;
- __be16 id;
- u8 protocol;
u8 ecn; /* RFC3168 support */
u16 max_df_size; /* largest frag with DF set seen */
int iif;
- int vif; /* L3 master device index */
unsigned int rid;
struct inet_peer *peer;
};
@@ -89,49 +75,9 @@ static u8 ip4_frag_ecn(u8 tos)
static struct inet_frags ip4_frags;
-int ip_frag_mem(struct net *net)
-{
- return sum_frag_mem_limit(&net->ipv4.frags);
-}
-
static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev,
struct net_device *dev);
-struct ip4_create_arg {
- struct iphdr *iph;
- u32 user;
- int vif;
-};
-
-static unsigned int ipqhashfn(__be16 id, __be32 saddr, __be32 daddr, u8 prot)
-{
- net_get_random_once(&ip4_frags.rnd, sizeof(ip4_frags.rnd));
- return jhash_3words((__force u32)id << 16 | prot,
- (__force u32)saddr, (__force u32)daddr,
- ip4_frags.rnd);
-}
-
-static unsigned int ip4_hashfn(const struct inet_frag_queue *q)
-{
- const struct ipq *ipq;
-
- ipq = container_of(q, struct ipq, q);
- return ipqhashfn(ipq->id, ipq->saddr, ipq->daddr, ipq->protocol);
-}
-
-static bool ip4_frag_match(const struct inet_frag_queue *q, const void *a)
-{
- const struct ipq *qp;
- const struct ip4_create_arg *arg = a;
-
- qp = container_of(q, struct ipq, q);
- return qp->id == arg->iph->id &&
- qp->saddr == arg->iph->saddr &&
- qp->daddr == arg->iph->daddr &&
- qp->protocol == arg->iph->protocol &&
- qp->user == arg->user &&
- qp->vif == arg->vif;
-}
static void ip4_frag_init(struct inet_frag_queue *q, const void *a)
{
@@ -140,17 +86,12 @@ static void ip4_frag_init(struct inet_frag_queue *q, const void *a)
frags);
struct net *net = container_of(ipv4, struct net, ipv4);
- const struct ip4_create_arg *arg = a;
+ const struct frag_v4_compare_key *key = a;
- qp->protocol = arg->iph->protocol;
- qp->id = arg->iph->id;
- qp->ecn = ip4_frag_ecn(arg->iph->tos);
- qp->saddr = arg->iph->saddr;
- qp->daddr = arg->iph->daddr;
- qp->vif = arg->vif;
- qp->user = arg->user;
+ q->key.v4 = *key;
+ qp->ecn = 0;
qp->peer = q->net->max_dist ?
- inet_getpeer_v4(net->ipv4.peers, arg->iph->saddr, arg->vif, 1) :
+ inet_getpeer_v4(net->ipv4.peers, key->saddr, key->vif, 1) :
NULL;
}
@@ -168,7 +109,7 @@ static void ip4_frag_free(struct inet_frag_queue *q)
static void ipq_put(struct ipq *ipq)
{
- inet_frag_put(&ipq->q, &ip4_frags);
+ inet_frag_put(&ipq->q);
}
/* Kill ipq entry. It is not destroyed immediately,
@@ -176,7 +117,7 @@ static void ipq_put(struct ipq *ipq)
*/
static void ipq_kill(struct ipq *ipq)
{
- inet_frag_kill(&ipq->q, &ip4_frags);
+ inet_frag_kill(&ipq->q);
}
static bool frag_expire_skip_icmp(u32 user)
@@ -194,8 +135,11 @@ static bool frag_expire_skip_icmp(u32 user)
static void ip_expire(struct timer_list *t)
{
struct inet_frag_queue *frag = from_timer(frag, t, timer);
- struct ipq *qp;
+ const struct iphdr *iph;
+ struct sk_buff *head;
struct net *net;
+ struct ipq *qp;
+ int err;
qp = container_of(frag, struct ipq, q);
net = container_of(qp->q.net, struct net, ipv4.frags);
@@ -209,46 +153,38 @@ static void ip_expire(struct timer_list *t)
ipq_kill(qp);
__IP_INC_STATS(net, IPSTATS_MIB_REASMFAILS);
- if (!inet_frag_evicting(&qp->q)) {
- struct sk_buff *clone, *head = qp->q.fragments;
- const struct iphdr *iph;
- int err;
+ head = qp->q.fragments;
- __IP_INC_STATS(net, IPSTATS_MIB_REASMTIMEOUT);
+ __IP_INC_STATS(net, IPSTATS_MIB_REASMTIMEOUT);
- if (!(qp->q.flags & INET_FRAG_FIRST_IN) || !qp->q.fragments)
- goto out;
+ if (!(qp->q.flags & INET_FRAG_FIRST_IN) || !head)
+ goto out;
- head->dev = dev_get_by_index_rcu(net, qp->iif);
- if (!head->dev)
- goto out;
+ head->dev = dev_get_by_index_rcu(net, qp->iif);
+ if (!head->dev)
+ goto out;
- /* skb has no dst, perform route lookup again */
- iph = ip_hdr(head);
- err = ip_route_input_noref(head, iph->daddr, iph->saddr,
+ /* skb has no dst, perform route lookup again */
+ iph = ip_hdr(head);
+ err = ip_route_input_noref(head, iph->daddr, iph->saddr,
iph->tos, head->dev);
- if (err)
- goto out;
+ if (err)
+ goto out;
+
+ /* Only an end host needs to send an ICMP
+ * "Fragment Reassembly Timeout" message, per RFC792.
+ */
+ if (frag_expire_skip_icmp(qp->q.key.v4.user) &&
+ (skb_rtable(head)->rt_type != RTN_LOCAL))
+ goto out;
+
+ skb_get(head);
+ spin_unlock(&qp->q.lock);
+ icmp_send(head, ICMP_TIME_EXCEEDED, ICMP_EXC_FRAGTIME, 0);
+ kfree_skb(head);
+ goto out_rcu_unlock;
- /* Only an end host needs to send an ICMP
- * "Fragment Reassembly Timeout" message, per RFC792.
- */
- if (frag_expire_skip_icmp(qp->user) &&
- (skb_rtable(head)->rt_type != RTN_LOCAL))
- goto out;
-
- clone = skb_clone(head, GFP_ATOMIC);
-
- /* Send an ICMP "Fragment Reassembly Timeout" message. */
- if (clone) {
- spin_unlock(&qp->q.lock);
- icmp_send(clone, ICMP_TIME_EXCEEDED,
- ICMP_EXC_FRAGTIME, 0);
- consume_skb(clone);
- goto out_rcu_unlock;
- }
- }
out:
spin_unlock(&qp->q.lock);
out_rcu_unlock:
@@ -262,21 +198,20 @@ out_rcu_unlock:
static struct ipq *ip_find(struct net *net, struct iphdr *iph,
u32 user, int vif)
{
+ struct frag_v4_compare_key key = {
+ .saddr = iph->saddr,
+ .daddr = iph->daddr,
+ .user = user,
+ .vif = vif,
+ .id = iph->id,
+ .protocol = iph->protocol,
+ };
struct inet_frag_queue *q;
- struct ip4_create_arg arg;
- unsigned int hash;
-
- arg.iph = iph;
- arg.user = user;
- arg.vif = vif;
- hash = ipqhashfn(iph->id, iph->saddr, iph->daddr, iph->protocol);
-
- q = inet_frag_find(&net->ipv4.frags, &ip4_frags, &arg, hash);
- if (IS_ERR_OR_NULL(q)) {
- inet_frag_maybe_warn_overflow(q, pr_fmt());
+ q = inet_frag_find(&net->ipv4.frags, &key);
+ if (!q)
return NULL;
- }
+
return container_of(q, struct ipq, q);
}
@@ -410,13 +345,13 @@ static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb)
* this fragment, right?
*/
prev = qp->q.fragments_tail;
- if (!prev || FRAG_CB(prev)->offset < offset) {
+ if (!prev || prev->ip_defrag_offset < offset) {
next = NULL;
goto found;
}
prev = NULL;
for (next = qp->q.fragments; next != NULL; next = next->next) {
- if (FRAG_CB(next)->offset >= offset)
+ if (next->ip_defrag_offset >= offset)
break; /* bingo! */
prev = next;
}
@@ -427,7 +362,7 @@ found:
* any overlaps are eliminated.
*/
if (prev) {
- int i = (FRAG_CB(prev)->offset + prev->len) - offset;
+ int i = (prev->ip_defrag_offset + prev->len) - offset;
if (i > 0) {
offset += i;
@@ -444,8 +379,8 @@ found:
err = -ENOMEM;
- while (next && FRAG_CB(next)->offset < end) {
- int i = end - FRAG_CB(next)->offset; /* overlap is 'i' bytes */
+ while (next && next->ip_defrag_offset < end) {
+ int i = end - next->ip_defrag_offset; /* overlap is 'i' bytes */
if (i < next->len) {
/* Eat head of the next overlapped fragment
@@ -453,7 +388,7 @@ found:
*/
if (!pskb_pull(next, i))
goto err;
- FRAG_CB(next)->offset += i;
+ next->ip_defrag_offset += i;
qp->q.meat -= i;
if (next->ip_summed != CHECKSUM_UNNECESSARY)
next->ip_summed = CHECKSUM_NONE;
@@ -477,7 +412,13 @@ found:
}
}
- FRAG_CB(skb)->offset = offset;
+ /* Note : skb->ip_defrag_offset and skb->dev share the same location */
+ dev = skb->dev;
+ if (dev)
+ qp->iif = dev->ifindex;
+ /* Makes sure compiler wont do silly aliasing games */
+ barrier();
+ skb->ip_defrag_offset = offset;
/* Insert this fragment in the chain of fragments. */
skb->next = next;
@@ -488,11 +429,6 @@ found:
else
qp->q.fragments = skb;
- dev = skb->dev;
- if (dev) {
- qp->iif = dev->ifindex;
- skb->dev = NULL;
- }
qp->q.stamp = skb->tstamp;
qp->q.meat += skb->len;
qp->ecn |= ecn;
@@ -568,7 +504,7 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev,
}
WARN_ON(!head);
- WARN_ON(FRAG_CB(head)->offset != 0);
+ WARN_ON(head->ip_defrag_offset != 0);
/* Allocate a new buffer for the datagram. */
ihlen = ip_hdrlen(head);
@@ -656,7 +592,7 @@ out_nomem:
err = -ENOMEM;
goto out_fail;
out_oversize:
- net_info_ratelimited("Oversized IP packet from %pI4\n", &qp->saddr);
+ net_info_ratelimited("Oversized IP packet from %pI4\n", &qp->q.key.v4.saddr);
out_fail:
__IP_INC_STATS(net, IPSTATS_MIB_REASMFAILS);
return err;
@@ -731,23 +667,23 @@ struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user)
EXPORT_SYMBOL(ip_check_defrag);
#ifdef CONFIG_SYSCTL
-static int zero;
+static long zero;
static struct ctl_table ip4_frags_ns_ctl_table[] = {
{
.procname = "ipfrag_high_thresh",
.data = &init_net.ipv4.frags.high_thresh,
- .maxlen = sizeof(int),
+ .maxlen = sizeof(unsigned long),
.mode = 0644,
- .proc_handler = proc_dointvec_minmax,
+ .proc_handler = proc_doulongvec_minmax,
.extra1 = &init_net.ipv4.frags.low_thresh
},
{
.procname = "ipfrag_low_thresh",
.data = &init_net.ipv4.frags.low_thresh,
- .maxlen = sizeof(int),
+ .maxlen = sizeof(unsigned long),
.mode = 0644,
- .proc_handler = proc_dointvec_minmax,
+ .proc_handler = proc_doulongvec_minmax,
.extra1 = &zero,
.extra2 = &init_net.ipv4.frags.high_thresh
},
@@ -846,6 +782,8 @@ static void __init ip4_frags_ctl_register(void)
static int __net_init ipv4_frags_init_net(struct net *net)
{
+ int res;
+
/* Fragment cache limits.
*
* The fragment memory accounting code, (tries to) account for
@@ -870,16 +808,21 @@ static int __net_init ipv4_frags_init_net(struct net *net)
net->ipv4.frags.timeout = IP_FRAG_TIME;
net->ipv4.frags.max_dist = 64;
-
- inet_frags_init_net(&net->ipv4.frags);
-
- return ip4_frags_ns_ctl_register(net);
+ net->ipv4.frags.f = &ip4_frags;
+
+ res = inet_frags_init_net(&net->ipv4.frags);
+ if (res < 0)
+ return res;
+ res = ip4_frags_ns_ctl_register(net);
+ if (res < 0)
+ inet_frags_exit_net(&net->ipv4.frags);
+ return res;
}
static void __net_exit ipv4_frags_exit_net(struct net *net)
{
ip4_frags_ns_ctl_unregister(net);
- inet_frags_exit_net(&net->ipv4.frags, &ip4_frags);
+ inet_frags_exit_net(&net->ipv4.frags);
}
static struct pernet_operations ip4_frags_ops = {
@@ -887,17 +830,49 @@ static struct pernet_operations ip4_frags_ops = {
.exit = ipv4_frags_exit_net,
};
+
+static u32 ip4_key_hashfn(const void *data, u32 len, u32 seed)
+{
+ return jhash2(data,
+ sizeof(struct frag_v4_compare_key) / sizeof(u32), seed);
+}
+
+static u32 ip4_obj_hashfn(const void *data, u32 len, u32 seed)
+{
+ const struct inet_frag_queue *fq = data;
+
+ return jhash2((const u32 *)&fq->key.v4,
+ sizeof(struct frag_v4_compare_key) / sizeof(u32), seed);
+}
+
+static int ip4_obj_cmpfn(struct rhashtable_compare_arg *arg, const void *ptr)
+{
+ const struct frag_v4_compare_key *key = arg->key;
+ const struct inet_frag_queue *fq = ptr;
+
+ return !!memcmp(&fq->key, key, sizeof(*key));
+}
+
+static const struct rhashtable_params ip4_rhash_params = {
+ .head_offset = offsetof(struct inet_frag_queue, node),
+ .key_offset = offsetof(struct inet_frag_queue, key),
+ .key_len = sizeof(struct frag_v4_compare_key),
+ .hashfn = ip4_key_hashfn,
+ .obj_hashfn = ip4_obj_hashfn,
+ .obj_cmpfn = ip4_obj_cmpfn,
+ .automatic_shrinking = true,
+};
+
void __init ipfrag_init(void)
{
- ip4_frags_ctl_register();
- register_pernet_subsys(&ip4_frags_ops);
- ip4_frags.hashfn = ip4_hashfn;
ip4_frags.constructor = ip4_frag_init;
ip4_frags.destructor = ip4_frag_free;
ip4_frags.qsize = sizeof(struct ipq);
- ip4_frags.match = ip4_frag_match;
ip4_frags.frag_expire = ip_expire;
ip4_frags.frags_cache_name = ip_frag_cache_name;
+ ip4_frags.rhash_params = ip4_rhash_params;
if (inet_frags_init(&ip4_frags))
panic("IP: failed to allocate ip4_frags cache\n");
+ ip4_frags_ctl_register();
+ register_pernet_subsys(&ip4_frags_ops);
}