Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * INET An implementation of the TCP/IP protocol suite for the LINUX |
| 3 | * operating system. INET is implemented using the BSD Socket |
| 4 | * interface as the means of communication with the user level. |
| 5 | * |
| 6 | * The IP fragmentation functionality. |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 7 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 8 | * Authors: Fred N. van Kempen <waltje@uWalt.NL.Mugnet.ORG> |
Alan Cox | 113aa83 | 2008-10-13 19:01:08 -0700 | [diff] [blame] | 9 | * Alan Cox <alan@lxorguk.ukuu.org.uk> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | * |
| 11 | * Fixes: |
| 12 | * Alan Cox : Split from ip.c , see ip_input.c for history. |
| 13 | * David S. Miller : Begin massive cleanup... |
| 14 | * Andi Kleen : Add sysctls. |
| 15 | * xxxx : Overlapfrag bug. |
| 16 | * Ultima : ip_expire() kernel panic. |
| 17 | * Bill Hawes : Frag accounting and evictor fixes. |
| 18 | * John McDonald : 0 length frag bug. |
| 19 | * Alexey Kuznetsov: SMP races, threading, cleanup. |
| 20 | * Patrick McHardy : LRU queue of frag heads for evictor. |
| 21 | */ |
| 22 | |
Joe Perches | afd46503 | 2012-03-12 07:03:32 +0000 | [diff] [blame] | 23 | #define pr_fmt(fmt) "IPv4: " fmt |
| 24 | |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 25 | #include <linux/compiler.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | #include <linux/module.h> |
| 27 | #include <linux/types.h> |
| 28 | #include <linux/mm.h> |
| 29 | #include <linux/jiffies.h> |
| 30 | #include <linux/skbuff.h> |
| 31 | #include <linux/list.h> |
| 32 | #include <linux/ip.h> |
| 33 | #include <linux/icmp.h> |
| 34 | #include <linux/netdevice.h> |
| 35 | #include <linux/jhash.h> |
| 36 | #include <linux/random.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 37 | #include <linux/slab.h> |
Shan Wei | e9017b5 | 2010-01-23 01:57:42 -0800 | [diff] [blame] | 38 | #include <net/route.h> |
| 39 | #include <net/dst.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | #include <net/sock.h> |
| 41 | #include <net/ip.h> |
| 42 | #include <net/icmp.h> |
| 43 | #include <net/checksum.h> |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 44 | #include <net/inetpeer.h> |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 45 | #include <net/inet_frag.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 46 | #include <linux/tcp.h> |
| 47 | #include <linux/udp.h> |
| 48 | #include <linux/inet.h> |
| 49 | #include <linux/netfilter_ipv4.h> |
Eric Dumazet | 6623e3b | 2011-01-05 07:52:55 +0000 | [diff] [blame] | 50 | #include <net/inet_ecn.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | |
| 52 | /* NOTE. Logic of IP defragmentation is parallel to corresponding IPv6 |
| 53 | * code now. If you change something here, _PLEASE_ update ipv6/reassembly.c |
| 54 | * as well. Or notify me, at least. --ANK |
| 55 | */ |
| 56 | |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 57 | static int sysctl_ipfrag_max_dist __read_mostly = 64; |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 58 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 59 | struct ipfrag_skb_cb |
| 60 | { |
| 61 | struct inet_skb_parm h; |
| 62 | int offset; |
| 63 | }; |
| 64 | |
Jianjun Kong | fd3f8c4 | 2008-11-03 02:47:38 -0800 | [diff] [blame] | 65 | #define FRAG_CB(skb) ((struct ipfrag_skb_cb *)((skb)->cb)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 66 | |
| 67 | /* Describe an entry in the "incomplete datagrams" queue. */ |
| 68 | struct ipq { |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 69 | struct inet_frag_queue q; |
| 70 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 71 | u32 user; |
Al Viro | 1827777 | 2006-09-26 22:19:02 -0700 | [diff] [blame] | 72 | __be32 saddr; |
| 73 | __be32 daddr; |
| 74 | __be16 id; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 75 | u8 protocol; |
Eric Dumazet | 6623e3b | 2011-01-05 07:52:55 +0000 | [diff] [blame] | 76 | u8 ecn; /* RFC3168 support */ |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 77 | int iif; |
| 78 | unsigned int rid; |
| 79 | struct inet_peer *peer; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 80 | }; |
| 81 | |
Eric Dumazet | 5173cc0 | 2011-05-16 08:37:37 +0000 | [diff] [blame] | 82 | /* RFC 3168 support : |
| 83 | * We want to check ECN values of all fragments, do detect invalid combinations. |
| 84 | * In ipq->ecn, we store the OR value of each ip4_frag_ecn() fragment value. |
| 85 | */ |
David S. Miller | 1d1652c | 2011-05-17 17:28:02 -0400 | [diff] [blame] | 86 | #define IPFRAG_ECN_NOT_ECT 0x01 /* one frag had ECN_NOT_ECT */ |
| 87 | #define IPFRAG_ECN_ECT_1 0x02 /* one frag had ECN_ECT_1 */ |
| 88 | #define IPFRAG_ECN_ECT_0 0x04 /* one frag had ECN_ECT_0 */ |
| 89 | #define IPFRAG_ECN_CE 0x08 /* one frag had ECN_CE */ |
Eric Dumazet | 6623e3b | 2011-01-05 07:52:55 +0000 | [diff] [blame] | 90 | |
| 91 | static inline u8 ip4_frag_ecn(u8 tos) |
| 92 | { |
Eric Dumazet | 5173cc0 | 2011-05-16 08:37:37 +0000 | [diff] [blame] | 93 | return 1 << (tos & INET_ECN_MASK); |
Eric Dumazet | 6623e3b | 2011-01-05 07:52:55 +0000 | [diff] [blame] | 94 | } |
| 95 | |
Eric Dumazet | 5173cc0 | 2011-05-16 08:37:37 +0000 | [diff] [blame] | 96 | /* Given the OR values of all fragments, apply RFC 3168 5.3 requirements |
| 97 | * Value : 0xff if frame should be dropped. |
| 98 | * 0 or INET_ECN_CE value, to be ORed in to final iph->tos field |
| 99 | */ |
| 100 | static const u8 ip4_frag_ecn_table[16] = { |
| 101 | /* at least one fragment had CE, and others ECT_0 or ECT_1 */ |
| 102 | [IPFRAG_ECN_CE | IPFRAG_ECN_ECT_0] = INET_ECN_CE, |
| 103 | [IPFRAG_ECN_CE | IPFRAG_ECN_ECT_1] = INET_ECN_CE, |
| 104 | [IPFRAG_ECN_CE | IPFRAG_ECN_ECT_0 | IPFRAG_ECN_ECT_1] = INET_ECN_CE, |
| 105 | |
| 106 | /* invalid combinations : drop frame */ |
| 107 | [IPFRAG_ECN_NOT_ECT | IPFRAG_ECN_CE] = 0xff, |
| 108 | [IPFRAG_ECN_NOT_ECT | IPFRAG_ECN_ECT_0] = 0xff, |
| 109 | [IPFRAG_ECN_NOT_ECT | IPFRAG_ECN_ECT_1] = 0xff, |
| 110 | [IPFRAG_ECN_NOT_ECT | IPFRAG_ECN_ECT_0 | IPFRAG_ECN_ECT_1] = 0xff, |
| 111 | [IPFRAG_ECN_NOT_ECT | IPFRAG_ECN_CE | IPFRAG_ECN_ECT_0] = 0xff, |
| 112 | [IPFRAG_ECN_NOT_ECT | IPFRAG_ECN_CE | IPFRAG_ECN_ECT_1] = 0xff, |
| 113 | [IPFRAG_ECN_NOT_ECT | IPFRAG_ECN_CE | IPFRAG_ECN_ECT_0 | IPFRAG_ECN_ECT_1] = 0xff, |
| 114 | }; |
| 115 | |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 116 | static struct inet_frags ip4_frags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 117 | |
Pavel Emelyanov | e5a2bb8 | 2008-01-22 06:06:23 -0800 | [diff] [blame] | 118 | int ip_frag_nqueues(struct net *net) |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 119 | { |
Pavel Emelyanov | e5a2bb8 | 2008-01-22 06:06:23 -0800 | [diff] [blame] | 120 | return net->ipv4.frags.nqueues; |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 121 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 122 | |
Pavel Emelyanov | 6ddc082 | 2008-01-22 06:07:25 -0800 | [diff] [blame] | 123 | int ip_frag_mem(struct net *net) |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 124 | { |
Pavel Emelyanov | 6ddc082 | 2008-01-22 06:07:25 -0800 | [diff] [blame] | 125 | return atomic_read(&net->ipv4.frags.mem); |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 126 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 127 | |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 128 | static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev, |
| 129 | struct net_device *dev); |
| 130 | |
Pavel Emelyanov | c6fda28 | 2007-10-17 19:46:47 -0700 | [diff] [blame] | 131 | struct ip4_create_arg { |
| 132 | struct iphdr *iph; |
| 133 | u32 user; |
| 134 | }; |
| 135 | |
Al Viro | 1827777 | 2006-09-26 22:19:02 -0700 | [diff] [blame] | 136 | static unsigned int ipqhashfn(__be16 id, __be32 saddr, __be32 daddr, u8 prot) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 137 | { |
Al Viro | 1827777 | 2006-09-26 22:19:02 -0700 | [diff] [blame] | 138 | return jhash_3words((__force u32)id << 16 | prot, |
| 139 | (__force u32)saddr, (__force u32)daddr, |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 140 | ip4_frags.rnd) & (INETFRAGS_HASHSZ - 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 141 | } |
| 142 | |
Pavel Emelyanov | 321a3a9 | 2007-10-15 02:38:08 -0700 | [diff] [blame] | 143 | static unsigned int ip4_hashfn(struct inet_frag_queue *q) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 144 | { |
Pavel Emelyanov | 321a3a9 | 2007-10-15 02:38:08 -0700 | [diff] [blame] | 145 | struct ipq *ipq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 146 | |
Pavel Emelyanov | 321a3a9 | 2007-10-15 02:38:08 -0700 | [diff] [blame] | 147 | ipq = container_of(q, struct ipq, q); |
| 148 | return ipqhashfn(ipq->id, ipq->saddr, ipq->daddr, ipq->protocol); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 149 | } |
| 150 | |
Eric Dumazet | cbc264c | 2012-05-18 05:57:13 +0200 | [diff] [blame] | 151 | static bool ip4_frag_match(struct inet_frag_queue *q, void *a) |
Pavel Emelyanov | abd6523 | 2007-10-17 19:47:21 -0700 | [diff] [blame] | 152 | { |
| 153 | struct ipq *qp; |
| 154 | struct ip4_create_arg *arg = a; |
| 155 | |
| 156 | qp = container_of(q, struct ipq, q); |
Eric Dumazet | a02cec2 | 2010-09-22 20:43:57 +0000 | [diff] [blame] | 157 | return qp->id == arg->iph->id && |
Eric Dumazet | cbc264c | 2012-05-18 05:57:13 +0200 | [diff] [blame] | 158 | qp->saddr == arg->iph->saddr && |
| 159 | qp->daddr == arg->iph->daddr && |
| 160 | qp->protocol == arg->iph->protocol && |
| 161 | qp->user == arg->user; |
Pavel Emelyanov | abd6523 | 2007-10-17 19:47:21 -0700 | [diff] [blame] | 162 | } |
| 163 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 164 | /* Memory Tracking Functions. */ |
Eric Dumazet | a95d8c8 | 2010-06-13 23:22:43 +0000 | [diff] [blame] | 165 | static void frag_kfree_skb(struct netns_frags *nf, struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 166 | { |
Pavel Emelyanov | 6ddc082 | 2008-01-22 06:07:25 -0800 | [diff] [blame] | 167 | atomic_sub(skb->truesize, &nf->mem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 168 | kfree_skb(skb); |
| 169 | } |
| 170 | |
Pavel Emelyanov | c6fda28 | 2007-10-17 19:46:47 -0700 | [diff] [blame] | 171 | static void ip4_frag_init(struct inet_frag_queue *q, void *a) |
| 172 | { |
| 173 | struct ipq *qp = container_of(q, struct ipq, q); |
Gao feng | 54db0cc | 2012-06-08 01:21:40 +0000 | [diff] [blame] | 174 | struct netns_ipv4 *ipv4 = container_of(q->net, struct netns_ipv4, |
| 175 | frags); |
| 176 | struct net *net = container_of(ipv4, struct net, ipv4); |
| 177 | |
Pavel Emelyanov | c6fda28 | 2007-10-17 19:46:47 -0700 | [diff] [blame] | 178 | struct ip4_create_arg *arg = a; |
| 179 | |
| 180 | qp->protocol = arg->iph->protocol; |
| 181 | qp->id = arg->iph->id; |
Eric Dumazet | 6623e3b | 2011-01-05 07:52:55 +0000 | [diff] [blame] | 182 | qp->ecn = ip4_frag_ecn(arg->iph->tos); |
Pavel Emelyanov | c6fda28 | 2007-10-17 19:46:47 -0700 | [diff] [blame] | 183 | qp->saddr = arg->iph->saddr; |
| 184 | qp->daddr = arg->iph->daddr; |
| 185 | qp->user = arg->user; |
| 186 | qp->peer = sysctl_ipfrag_max_dist ? |
David S. Miller | c0efc88 | 2012-06-09 19:12:36 -0700 | [diff] [blame] | 187 | inet_getpeer_v4(net->ipv4.peers, arg->iph->saddr, 1) : NULL; |
Pavel Emelyanov | c6fda28 | 2007-10-17 19:46:47 -0700 | [diff] [blame] | 188 | } |
| 189 | |
Pavel Emelyanov | 1e4b828 | 2007-10-15 02:39:14 -0700 | [diff] [blame] | 190 | static __inline__ void ip4_frag_free(struct inet_frag_queue *q) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 191 | { |
Pavel Emelyanov | 1e4b828 | 2007-10-15 02:39:14 -0700 | [diff] [blame] | 192 | struct ipq *qp; |
| 193 | |
| 194 | qp = container_of(q, struct ipq, q); |
| 195 | if (qp->peer) |
| 196 | inet_putpeer(qp->peer); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 197 | } |
| 198 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 199 | |
| 200 | /* Destruction primitives. */ |
| 201 | |
Pavel Emelyanov | 4b6cb5d | 2007-10-15 02:41:09 -0700 | [diff] [blame] | 202 | static __inline__ void ipq_put(struct ipq *ipq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 203 | { |
Pavel Emelyanov | 762cc40 | 2007-10-15 02:41:56 -0700 | [diff] [blame] | 204 | inet_frag_put(&ipq->q, &ip4_frags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | } |
| 206 | |
| 207 | /* Kill ipq entry. It is not destroyed immediately, |
| 208 | * because caller (and someone more) holds reference count. |
| 209 | */ |
| 210 | static void ipq_kill(struct ipq *ipq) |
| 211 | { |
Pavel Emelyanov | 277e650 | 2007-10-15 02:37:18 -0700 | [diff] [blame] | 212 | inet_frag_kill(&ipq->q, &ip4_frags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 213 | } |
| 214 | |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 215 | /* Memory limiting on fragments. Evictor trashes the oldest |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 216 | * fragment queue until we are back under the threshold. |
| 217 | */ |
Pavel Emelyanov | 6ddc082 | 2008-01-22 06:07:25 -0800 | [diff] [blame] | 218 | static void ip_evictor(struct net *net) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 219 | { |
Pavel Emelyanov | 8e7999c | 2007-10-15 02:40:06 -0700 | [diff] [blame] | 220 | int evicted; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 221 | |
Amerigo Wang | 6b10286 | 2012-09-18 16:50:11 +0000 | [diff] [blame] | 222 | evicted = inet_frag_evictor(&net->ipv4.frags, &ip4_frags, false); |
Pavel Emelyanov | 8e7999c | 2007-10-15 02:40:06 -0700 | [diff] [blame] | 223 | if (evicted) |
Pavel Emelyanov | c5346fe | 2008-07-16 20:20:33 -0700 | [diff] [blame] | 224 | IP_ADD_STATS_BH(net, IPSTATS_MIB_REASMFAILS, evicted); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 225 | } |
| 226 | |
| 227 | /* |
| 228 | * Oops, a fragment queue timed out. Kill it and send an ICMP reply. |
| 229 | */ |
| 230 | static void ip_expire(unsigned long arg) |
| 231 | { |
Pavel Emelyanov | e521db9 | 2007-10-17 19:45:23 -0700 | [diff] [blame] | 232 | struct ipq *qp; |
Pavel Emelyanov | 84a3aa0 | 2008-07-16 20:19:08 -0700 | [diff] [blame] | 233 | struct net *net; |
Pavel Emelyanov | e521db9 | 2007-10-17 19:45:23 -0700 | [diff] [blame] | 234 | |
| 235 | qp = container_of((struct inet_frag_queue *) arg, struct ipq, q); |
Pavel Emelyanov | 84a3aa0 | 2008-07-16 20:19:08 -0700 | [diff] [blame] | 236 | net = container_of(qp->q.net, struct net, ipv4.frags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 237 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 238 | spin_lock(&qp->q.lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | |
Joe Perches | bc578a5 | 2008-03-28 16:35:27 -0700 | [diff] [blame] | 240 | if (qp->q.last_in & INET_FRAG_COMPLETE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 241 | goto out; |
| 242 | |
| 243 | ipq_kill(qp); |
| 244 | |
Pavel Emelyanov | 7c73a6f | 2008-07-16 20:20:11 -0700 | [diff] [blame] | 245 | IP_INC_STATS_BH(net, IPSTATS_MIB_REASMTIMEOUT); |
| 246 | IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 247 | |
Joe Perches | bc578a5 | 2008-03-28 16:35:27 -0700 | [diff] [blame] | 248 | if ((qp->q.last_in & INET_FRAG_FIRST_IN) && qp->q.fragments != NULL) { |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 249 | struct sk_buff *head = qp->q.fragments; |
Eric Dumazet | 64f3b9e | 2011-05-04 10:02:26 +0000 | [diff] [blame] | 250 | const struct iphdr *iph; |
| 251 | int err; |
Denis V. Lunev | cb84663 | 2008-03-24 15:31:00 -0700 | [diff] [blame] | 252 | |
Eric Dumazet | 69df9d5 | 2009-11-05 20:59:47 -0800 | [diff] [blame] | 253 | rcu_read_lock(); |
| 254 | head->dev = dev_get_by_index_rcu(net, qp->iif); |
Shan Wei | e9017b5 | 2010-01-23 01:57:42 -0800 | [diff] [blame] | 255 | if (!head->dev) |
| 256 | goto out_rcu_unlock; |
| 257 | |
Eric Dumazet | 64f3b9e | 2011-05-04 10:02:26 +0000 | [diff] [blame] | 258 | /* skb dst is stale, drop it, and perform route lookup again */ |
| 259 | skb_dst_drop(head); |
| 260 | iph = ip_hdr(head); |
David S. Miller | c6cffba | 2012-07-26 11:14:38 +0000 | [diff] [blame] | 261 | err = ip_route_input_noref(head, iph->daddr, iph->saddr, |
| 262 | iph->tos, head->dev); |
Eric Dumazet | 64f3b9e | 2011-05-04 10:02:26 +0000 | [diff] [blame] | 263 | if (err) |
| 264 | goto out_rcu_unlock; |
| 265 | |
Shan Wei | e9017b5 | 2010-01-23 01:57:42 -0800 | [diff] [blame] | 266 | /* |
Eric Dumazet | 64f3b9e | 2011-05-04 10:02:26 +0000 | [diff] [blame] | 267 | * Only an end host needs to send an ICMP |
| 268 | * "Fragment Reassembly Timeout" message, per RFC792. |
Shan Wei | e9017b5 | 2010-01-23 01:57:42 -0800 | [diff] [blame] | 269 | */ |
David S. Miller | 595fc71 | 2011-07-05 01:05:48 -0700 | [diff] [blame] | 270 | if (qp->user == IP_DEFRAG_AF_PACKET || |
| 271 | (qp->user == IP_DEFRAG_CONNTRACK_IN && |
| 272 | skb_rtable(head)->rt_type != RTN_LOCAL)) |
Eric Dumazet | 64f3b9e | 2011-05-04 10:02:26 +0000 | [diff] [blame] | 273 | goto out_rcu_unlock; |
Shan Wei | e9017b5 | 2010-01-23 01:57:42 -0800 | [diff] [blame] | 274 | |
Shan Wei | e9017b5 | 2010-01-23 01:57:42 -0800 | [diff] [blame] | 275 | |
| 276 | /* Send an ICMP "Fragment Reassembly Timeout" message. */ |
| 277 | icmp_send(head, ICMP_TIME_EXCEEDED, ICMP_EXC_FRAGTIME, 0); |
Shan Wei | e9017b5 | 2010-01-23 01:57:42 -0800 | [diff] [blame] | 278 | out_rcu_unlock: |
Patrick McHardy | d1c9ae6 | 2010-02-02 11:46:50 -0800 | [diff] [blame] | 279 | rcu_read_unlock(); |
| 280 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 281 | out: |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 282 | spin_unlock(&qp->q.lock); |
Pavel Emelyanov | 4b6cb5d | 2007-10-15 02:41:09 -0700 | [diff] [blame] | 283 | ipq_put(qp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 284 | } |
| 285 | |
Pavel Emelyanov | abd6523 | 2007-10-17 19:47:21 -0700 | [diff] [blame] | 286 | /* Find the correct entry in the "incomplete datagrams" queue for |
| 287 | * this IP datagram, and create new one, if nothing is found. |
| 288 | */ |
Pavel Emelyanov | ac18e75 | 2008-01-22 06:02:14 -0800 | [diff] [blame] | 289 | static inline struct ipq *ip_find(struct net *net, struct iphdr *iph, u32 user) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 290 | { |
Pavel Emelyanov | c6fda28 | 2007-10-17 19:46:47 -0700 | [diff] [blame] | 291 | struct inet_frag_queue *q; |
| 292 | struct ip4_create_arg arg; |
Pavel Emelyanov | abd6523 | 2007-10-17 19:47:21 -0700 | [diff] [blame] | 293 | unsigned int hash; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 294 | |
Pavel Emelyanov | c6fda28 | 2007-10-17 19:46:47 -0700 | [diff] [blame] | 295 | arg.iph = iph; |
| 296 | arg.user = user; |
Pavel Emelyanov | 9a37580 | 2008-06-27 20:06:08 -0700 | [diff] [blame] | 297 | |
| 298 | read_lock(&ip4_frags.lock); |
Pavel Emelyanov | abd6523 | 2007-10-17 19:47:21 -0700 | [diff] [blame] | 299 | hash = ipqhashfn(iph->id, iph->saddr, iph->daddr, iph->protocol); |
Pavel Emelyanov | c6fda28 | 2007-10-17 19:46:47 -0700 | [diff] [blame] | 300 | |
Pavel Emelyanov | ac18e75 | 2008-01-22 06:02:14 -0800 | [diff] [blame] | 301 | q = inet_frag_find(&net->ipv4.frags, &ip4_frags, &arg, hash); |
Pavel Emelyanov | c6fda28 | 2007-10-17 19:46:47 -0700 | [diff] [blame] | 302 | if (q == NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 303 | goto out_nomem; |
| 304 | |
Pavel Emelyanov | c6fda28 | 2007-10-17 19:46:47 -0700 | [diff] [blame] | 305 | return container_of(q, struct ipq, q); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 306 | |
| 307 | out_nomem: |
Joe Perches | afd46503 | 2012-03-12 07:03:32 +0000 | [diff] [blame] | 308 | LIMIT_NETDEBUG(KERN_ERR pr_fmt("ip_frag_create: no memory left !\n")); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 309 | return NULL; |
| 310 | } |
| 311 | |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 312 | /* Is the fragment too far ahead to be part of ipq? */ |
| 313 | static inline int ip_frag_too_far(struct ipq *qp) |
| 314 | { |
| 315 | struct inet_peer *peer = qp->peer; |
| 316 | unsigned int max = sysctl_ipfrag_max_dist; |
| 317 | unsigned int start, end; |
| 318 | |
| 319 | int rc; |
| 320 | |
| 321 | if (!peer || !max) |
| 322 | return 0; |
| 323 | |
| 324 | start = qp->rid; |
| 325 | end = atomic_inc_return(&peer->rid); |
| 326 | qp->rid = end; |
| 327 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 328 | rc = qp->q.fragments && (end - start) > max; |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 329 | |
| 330 | if (rc) { |
Pavel Emelyanov | 7c73a6f | 2008-07-16 20:20:11 -0700 | [diff] [blame] | 331 | struct net *net; |
| 332 | |
| 333 | net = container_of(qp->q.net, struct net, ipv4.frags); |
| 334 | IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS); |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 335 | } |
| 336 | |
| 337 | return rc; |
| 338 | } |
| 339 | |
| 340 | static int ip_frag_reinit(struct ipq *qp) |
| 341 | { |
| 342 | struct sk_buff *fp; |
| 343 | |
Pavel Emelyanov | b2fd532 | 2008-01-22 06:09:37 -0800 | [diff] [blame] | 344 | if (!mod_timer(&qp->q.timer, jiffies + qp->q.net->timeout)) { |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 345 | atomic_inc(&qp->q.refcnt); |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 346 | return -ETIMEDOUT; |
| 347 | } |
| 348 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 349 | fp = qp->q.fragments; |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 350 | do { |
| 351 | struct sk_buff *xp = fp->next; |
Eric Dumazet | a95d8c8 | 2010-06-13 23:22:43 +0000 | [diff] [blame] | 352 | frag_kfree_skb(qp->q.net, fp); |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 353 | fp = xp; |
| 354 | } while (fp); |
| 355 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 356 | qp->q.last_in = 0; |
| 357 | qp->q.len = 0; |
| 358 | qp->q.meat = 0; |
| 359 | qp->q.fragments = NULL; |
Changli Gao | d6bebca | 2010-06-29 04:39:37 +0000 | [diff] [blame] | 360 | qp->q.fragments_tail = NULL; |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 361 | qp->iif = 0; |
Eric Dumazet | 6623e3b | 2011-01-05 07:52:55 +0000 | [diff] [blame] | 362 | qp->ecn = 0; |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 363 | |
| 364 | return 0; |
| 365 | } |
| 366 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 367 | /* Add new segment to existing queue. */ |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 368 | static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 369 | { |
| 370 | struct sk_buff *prev, *next; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 371 | struct net_device *dev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 372 | int flags, offset; |
| 373 | int ihl, end; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 374 | int err = -ENOENT; |
Eric Dumazet | 6623e3b | 2011-01-05 07:52:55 +0000 | [diff] [blame] | 375 | u8 ecn; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 376 | |
Joe Perches | bc578a5 | 2008-03-28 16:35:27 -0700 | [diff] [blame] | 377 | if (qp->q.last_in & INET_FRAG_COMPLETE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 378 | goto err; |
| 379 | |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 380 | if (!(IPCB(skb)->flags & IPSKB_FRAG_COMPLETE) && |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 381 | unlikely(ip_frag_too_far(qp)) && |
| 382 | unlikely(err = ip_frag_reinit(qp))) { |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 383 | ipq_kill(qp); |
| 384 | goto err; |
| 385 | } |
| 386 | |
Eric Dumazet | 6623e3b | 2011-01-05 07:52:55 +0000 | [diff] [blame] | 387 | ecn = ip4_frag_ecn(ip_hdr(skb)->tos); |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 388 | offset = ntohs(ip_hdr(skb)->frag_off); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 389 | flags = offset & ~IP_OFFSET; |
| 390 | offset &= IP_OFFSET; |
| 391 | offset <<= 3; /* offset is in 8-byte chunks */ |
Arnaldo Carvalho de Melo | c9bdd4b | 2007-03-12 20:09:15 -0300 | [diff] [blame] | 392 | ihl = ip_hdrlen(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 393 | |
| 394 | /* Determine the position of this fragment. */ |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 395 | end = offset + skb->len - ihl; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 396 | err = -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 397 | |
| 398 | /* Is this the final fragment? */ |
| 399 | if ((flags & IP_MF) == 0) { |
| 400 | /* If we already have some bits beyond end |
Justin P. Mattock | 42b2aa8 | 2011-11-28 20:31:00 -0800 | [diff] [blame] | 401 | * or have different end, the segment is corrupted. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 402 | */ |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 403 | if (end < qp->q.len || |
Joe Perches | bc578a5 | 2008-03-28 16:35:27 -0700 | [diff] [blame] | 404 | ((qp->q.last_in & INET_FRAG_LAST_IN) && end != qp->q.len)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 405 | goto err; |
Joe Perches | bc578a5 | 2008-03-28 16:35:27 -0700 | [diff] [blame] | 406 | qp->q.last_in |= INET_FRAG_LAST_IN; |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 407 | qp->q.len = end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 408 | } else { |
| 409 | if (end&7) { |
| 410 | end &= ~7; |
| 411 | if (skb->ip_summed != CHECKSUM_UNNECESSARY) |
| 412 | skb->ip_summed = CHECKSUM_NONE; |
| 413 | } |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 414 | if (end > qp->q.len) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 415 | /* Some bits beyond end -> corruption. */ |
Joe Perches | bc578a5 | 2008-03-28 16:35:27 -0700 | [diff] [blame] | 416 | if (qp->q.last_in & INET_FRAG_LAST_IN) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 417 | goto err; |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 418 | qp->q.len = end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 419 | } |
| 420 | } |
| 421 | if (end == offset) |
| 422 | goto err; |
| 423 | |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 424 | err = -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 425 | if (pskb_pull(skb, ihl) == NULL) |
| 426 | goto err; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 427 | |
| 428 | err = pskb_trim_rcsum(skb, end - offset); |
| 429 | if (err) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 430 | goto err; |
| 431 | |
| 432 | /* Find out which fragments are in front and at the back of us |
| 433 | * in the chain of fragments so far. We must know where to put |
| 434 | * this fragment, right? |
| 435 | */ |
Changli Gao | d6bebca | 2010-06-29 04:39:37 +0000 | [diff] [blame] | 436 | prev = qp->q.fragments_tail; |
| 437 | if (!prev || FRAG_CB(prev)->offset < offset) { |
| 438 | next = NULL; |
| 439 | goto found; |
| 440 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 441 | prev = NULL; |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 442 | for (next = qp->q.fragments; next != NULL; next = next->next) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 443 | if (FRAG_CB(next)->offset >= offset) |
| 444 | break; /* bingo! */ |
| 445 | prev = next; |
| 446 | } |
| 447 | |
Changli Gao | d6bebca | 2010-06-29 04:39:37 +0000 | [diff] [blame] | 448 | found: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 449 | /* We found where to put this one. Check for overlap with |
| 450 | * preceding fragment, and, if needed, align things so that |
| 451 | * any overlaps are eliminated. |
| 452 | */ |
| 453 | if (prev) { |
| 454 | int i = (FRAG_CB(prev)->offset + prev->len) - offset; |
| 455 | |
| 456 | if (i > 0) { |
| 457 | offset += i; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 458 | err = -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 459 | if (end <= offset) |
| 460 | goto err; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 461 | err = -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 462 | if (!pskb_pull(skb, i)) |
| 463 | goto err; |
| 464 | if (skb->ip_summed != CHECKSUM_UNNECESSARY) |
| 465 | skb->ip_summed = CHECKSUM_NONE; |
| 466 | } |
| 467 | } |
| 468 | |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 469 | err = -ENOMEM; |
| 470 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 471 | while (next && FRAG_CB(next)->offset < end) { |
| 472 | int i = end - FRAG_CB(next)->offset; /* overlap is 'i' bytes */ |
| 473 | |
| 474 | if (i < next->len) { |
| 475 | /* Eat head of the next overlapped fragment |
| 476 | * and leave the loop. The next ones cannot overlap. |
| 477 | */ |
| 478 | if (!pskb_pull(next, i)) |
| 479 | goto err; |
| 480 | FRAG_CB(next)->offset += i; |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 481 | qp->q.meat -= i; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 482 | if (next->ip_summed != CHECKSUM_UNNECESSARY) |
| 483 | next->ip_summed = CHECKSUM_NONE; |
| 484 | break; |
| 485 | } else { |
| 486 | struct sk_buff *free_it = next; |
| 487 | |
Peter Zijlstra | 47c6bf77 | 2006-12-12 19:48:59 +0100 | [diff] [blame] | 488 | /* Old fragment is completely overridden with |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 489 | * new one drop it. |
| 490 | */ |
| 491 | next = next->next; |
| 492 | |
| 493 | if (prev) |
| 494 | prev->next = next; |
| 495 | else |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 496 | qp->q.fragments = next; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 497 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 498 | qp->q.meat -= free_it->len; |
Eric Dumazet | a95d8c8 | 2010-06-13 23:22:43 +0000 | [diff] [blame] | 499 | frag_kfree_skb(qp->q.net, free_it); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 500 | } |
| 501 | } |
| 502 | |
| 503 | FRAG_CB(skb)->offset = offset; |
| 504 | |
| 505 | /* Insert this fragment in the chain of fragments. */ |
| 506 | skb->next = next; |
Changli Gao | d6bebca | 2010-06-29 04:39:37 +0000 | [diff] [blame] | 507 | if (!next) |
| 508 | qp->q.fragments_tail = skb; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 509 | if (prev) |
| 510 | prev->next = skb; |
| 511 | else |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 512 | qp->q.fragments = skb; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 513 | |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 514 | dev = skb->dev; |
| 515 | if (dev) { |
| 516 | qp->iif = dev->ifindex; |
| 517 | skb->dev = NULL; |
| 518 | } |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 519 | qp->q.stamp = skb->tstamp; |
| 520 | qp->q.meat += skb->len; |
Eric Dumazet | 6623e3b | 2011-01-05 07:52:55 +0000 | [diff] [blame] | 521 | qp->ecn |= ecn; |
Pavel Emelyanov | 6ddc082 | 2008-01-22 06:07:25 -0800 | [diff] [blame] | 522 | atomic_add(skb->truesize, &qp->q.net->mem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 523 | if (offset == 0) |
Joe Perches | bc578a5 | 2008-03-28 16:35:27 -0700 | [diff] [blame] | 524 | qp->q.last_in |= INET_FRAG_FIRST_IN; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 525 | |
Patrick McHardy | 5f2d04f | 2012-08-26 19:13:55 +0200 | [diff] [blame] | 526 | if (ip_hdr(skb)->frag_off & htons(IP_DF) && |
| 527 | skb->len + ihl > qp->q.max_size) |
| 528 | qp->q.max_size = skb->len + ihl; |
| 529 | |
Joe Perches | bc578a5 | 2008-03-28 16:35:27 -0700 | [diff] [blame] | 530 | if (qp->q.last_in == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) && |
| 531 | qp->q.meat == qp->q.len) |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 532 | return ip_frag_reasm(qp, prev, dev); |
| 533 | |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 534 | write_lock(&ip4_frags.lock); |
Pavel Emelyanov | 3140c25 | 2008-01-22 06:11:48 -0800 | [diff] [blame] | 535 | list_move_tail(&qp->q.lru_list, &qp->q.net->lru_list); |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 536 | write_unlock(&ip4_frags.lock); |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 537 | return -EINPROGRESS; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 538 | |
| 539 | err: |
| 540 | kfree_skb(skb); |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 541 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 542 | } |
| 543 | |
| 544 | |
| 545 | /* Build a new IP datagram from all its fragments. */ |
| 546 | |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 547 | static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev, |
| 548 | struct net_device *dev) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 549 | { |
Jorge Boncompte [DTI2] | 2bad35b | 2009-03-18 23:26:11 -0700 | [diff] [blame] | 550 | struct net *net = container_of(qp->q.net, struct net, ipv4.frags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 551 | struct iphdr *iph; |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 552 | struct sk_buff *fp, *head = qp->q.fragments; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 553 | int len; |
| 554 | int ihlen; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 555 | int err; |
Eric Dumazet | 3cc4949 | 2012-05-19 03:02:20 +0000 | [diff] [blame] | 556 | int sum_truesize; |
Eric Dumazet | 5173cc0 | 2011-05-16 08:37:37 +0000 | [diff] [blame] | 557 | u8 ecn; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 558 | |
| 559 | ipq_kill(qp); |
| 560 | |
Eric Dumazet | 5173cc0 | 2011-05-16 08:37:37 +0000 | [diff] [blame] | 561 | ecn = ip4_frag_ecn_table[qp->ecn]; |
| 562 | if (unlikely(ecn == 0xff)) { |
| 563 | err = -EINVAL; |
| 564 | goto out_fail; |
| 565 | } |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 566 | /* Make the one we just received the head. */ |
| 567 | if (prev) { |
| 568 | head = prev->next; |
| 569 | fp = skb_clone(head, GFP_ATOMIC); |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 570 | if (!fp) |
| 571 | goto out_nomem; |
| 572 | |
| 573 | fp->next = head->next; |
Changli Gao | d6bebca | 2010-06-29 04:39:37 +0000 | [diff] [blame] | 574 | if (!fp->next) |
| 575 | qp->q.fragments_tail = fp; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 576 | prev->next = fp; |
| 577 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 578 | skb_morph(head, qp->q.fragments); |
| 579 | head->next = qp->q.fragments->next; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 580 | |
Eric Dumazet | cbf8f7b | 2012-04-19 06:10:26 +0000 | [diff] [blame] | 581 | consume_skb(qp->q.fragments); |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 582 | qp->q.fragments = head; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 583 | } |
| 584 | |
Ilpo Järvinen | 547b792 | 2008-07-25 21:43:18 -0700 | [diff] [blame] | 585 | WARN_ON(head == NULL); |
| 586 | WARN_ON(FRAG_CB(head)->offset != 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 587 | |
| 588 | /* Allocate a new buffer for the datagram. */ |
Arnaldo Carvalho de Melo | c9bdd4b | 2007-03-12 20:09:15 -0300 | [diff] [blame] | 589 | ihlen = ip_hdrlen(head); |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 590 | len = ihlen + qp->q.len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 591 | |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 592 | err = -E2BIG; |
Stephen Hemminger | 132adf5 | 2007-03-08 20:44:43 -0800 | [diff] [blame] | 593 | if (len > 65535) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 594 | goto out_oversize; |
| 595 | |
| 596 | /* Head of list must not be cloned. */ |
| 597 | if (skb_cloned(head) && pskb_expand_head(head, 0, 0, GFP_ATOMIC)) |
| 598 | goto out_nomem; |
| 599 | |
| 600 | /* If the first fragment is fragmented itself, we split |
| 601 | * it to two chunks: the first with data and paged part |
| 602 | * and the second, holding only fragments. */ |
David S. Miller | 21dc330 | 2010-08-23 00:13:46 -0700 | [diff] [blame] | 603 | if (skb_has_frag_list(head)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 604 | struct sk_buff *clone; |
| 605 | int i, plen = 0; |
| 606 | |
| 607 | if ((clone = alloc_skb(0, GFP_ATOMIC)) == NULL) |
| 608 | goto out_nomem; |
| 609 | clone->next = head->next; |
| 610 | head->next = clone; |
| 611 | skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list; |
David S. Miller | d7fcf1a | 2009-06-09 00:19:37 -0700 | [diff] [blame] | 612 | skb_frag_list_init(head); |
Eric Dumazet | 9e903e0 | 2011-10-18 21:00:24 +0000 | [diff] [blame] | 613 | for (i = 0; i < skb_shinfo(head)->nr_frags; i++) |
| 614 | plen += skb_frag_size(&skb_shinfo(head)->frags[i]); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 615 | clone->len = clone->data_len = head->data_len - plen; |
| 616 | head->data_len -= clone->len; |
| 617 | head->len -= clone->len; |
| 618 | clone->csum = 0; |
| 619 | clone->ip_summed = head->ip_summed; |
Pavel Emelyanov | 6ddc082 | 2008-01-22 06:07:25 -0800 | [diff] [blame] | 620 | atomic_add(clone->truesize, &qp->q.net->mem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 621 | } |
| 622 | |
Arnaldo Carvalho de Melo | d56f90a | 2007-04-10 20:50:43 -0700 | [diff] [blame] | 623 | skb_push(head, head->data - skb_network_header(head)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 624 | |
Eric Dumazet | 3cc4949 | 2012-05-19 03:02:20 +0000 | [diff] [blame] | 625 | sum_truesize = head->truesize; |
| 626 | for (fp = head->next; fp;) { |
| 627 | bool headstolen; |
| 628 | int delta; |
| 629 | struct sk_buff *next = fp->next; |
| 630 | |
| 631 | sum_truesize += fp->truesize; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 632 | if (head->ip_summed != fp->ip_summed) |
| 633 | head->ip_summed = CHECKSUM_NONE; |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 634 | else if (head->ip_summed == CHECKSUM_COMPLETE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 635 | head->csum = csum_add(head->csum, fp->csum); |
Eric Dumazet | 3cc4949 | 2012-05-19 03:02:20 +0000 | [diff] [blame] | 636 | |
| 637 | if (skb_try_coalesce(head, fp, &headstolen, &delta)) { |
| 638 | kfree_skb_partial(fp, headstolen); |
| 639 | } else { |
| 640 | if (!skb_shinfo(head)->frag_list) |
| 641 | skb_shinfo(head)->frag_list = fp; |
| 642 | head->data_len += fp->len; |
| 643 | head->len += fp->len; |
| 644 | head->truesize += fp->truesize; |
| 645 | } |
| 646 | fp = next; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 647 | } |
Eric Dumazet | 3cc4949 | 2012-05-19 03:02:20 +0000 | [diff] [blame] | 648 | atomic_sub(sum_truesize, &qp->q.net->mem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 649 | |
| 650 | head->next = NULL; |
| 651 | head->dev = dev; |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 652 | head->tstamp = qp->q.stamp; |
Patrick McHardy | 5f2d04f | 2012-08-26 19:13:55 +0200 | [diff] [blame] | 653 | IPCB(head)->frag_max_size = qp->q.max_size; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 654 | |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 655 | iph = ip_hdr(head); |
Patrick McHardy | 5f2d04f | 2012-08-26 19:13:55 +0200 | [diff] [blame] | 656 | /* max_size != 0 implies at least one fragment had IP_DF set */ |
| 657 | iph->frag_off = qp->q.max_size ? htons(IP_DF) : 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 658 | iph->tot_len = htons(len); |
Eric Dumazet | 5173cc0 | 2011-05-16 08:37:37 +0000 | [diff] [blame] | 659 | iph->tos |= ecn; |
Jorge Boncompte [DTI2] | 2bad35b | 2009-03-18 23:26:11 -0700 | [diff] [blame] | 660 | IP_INC_STATS_BH(net, IPSTATS_MIB_REASMOKS); |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 661 | qp->q.fragments = NULL; |
Changli Gao | d6bebca | 2010-06-29 04:39:37 +0000 | [diff] [blame] | 662 | qp->q.fragments_tail = NULL; |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 663 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 664 | |
| 665 | out_nomem: |
Joe Perches | afd46503 | 2012-03-12 07:03:32 +0000 | [diff] [blame] | 666 | LIMIT_NETDEBUG(KERN_ERR pr_fmt("queue_glue: no memory for gluing queue %p\n"), |
| 667 | qp); |
David Howells | 4554247 | 2007-10-17 21:37:22 -0700 | [diff] [blame] | 668 | err = -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 669 | goto out_fail; |
| 670 | out_oversize: |
Joe Perches | e87cc47 | 2012-05-13 21:56:26 +0000 | [diff] [blame] | 671 | net_info_ratelimited("Oversized IP packet from %pI4\n", &qp->saddr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 672 | out_fail: |
David Ford | bbf31bf | 2009-11-29 23:02:22 -0800 | [diff] [blame] | 673 | IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS); |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 674 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 675 | } |
| 676 | |
| 677 | /* Process an incoming IP datagram fragment. */ |
Herbert Xu | 776c729 | 2007-10-14 00:38:32 -0700 | [diff] [blame] | 678 | int ip_defrag(struct sk_buff *skb, u32 user) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 679 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 680 | struct ipq *qp; |
Pavel Emelyanov | ac18e75 | 2008-01-22 06:02:14 -0800 | [diff] [blame] | 681 | struct net *net; |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 682 | |
Eric Dumazet | adf3090 | 2009-06-02 05:19:30 +0000 | [diff] [blame] | 683 | net = skb->dev ? dev_net(skb->dev) : dev_net(skb_dst(skb)->dev); |
Pavel Emelyanov | 7c73a6f | 2008-07-16 20:20:11 -0700 | [diff] [blame] | 684 | IP_INC_STATS_BH(net, IPSTATS_MIB_REASMREQDS); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 685 | |
| 686 | /* Start by cleaning up the memory. */ |
Amerigo Wang | 6b10286 | 2012-09-18 16:50:11 +0000 | [diff] [blame] | 687 | ip_evictor(net); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 688 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 689 | /* Lookup (or create) queue header */ |
Pavel Emelyanov | ac18e75 | 2008-01-22 06:02:14 -0800 | [diff] [blame] | 690 | if ((qp = ip_find(net, ip_hdr(skb), user)) != NULL) { |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 691 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 692 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 693 | spin_lock(&qp->q.lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 694 | |
Herbert Xu | 1706d58 | 2007-10-14 00:38:15 -0700 | [diff] [blame] | 695 | ret = ip_frag_queue(qp, skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 696 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 697 | spin_unlock(&qp->q.lock); |
Pavel Emelyanov | 4b6cb5d | 2007-10-15 02:41:09 -0700 | [diff] [blame] | 698 | ipq_put(qp); |
Herbert Xu | 776c729 | 2007-10-14 00:38:32 -0700 | [diff] [blame] | 699 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 700 | } |
| 701 | |
Pavel Emelyanov | 7c73a6f | 2008-07-16 20:20:11 -0700 | [diff] [blame] | 702 | IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 703 | kfree_skb(skb); |
Herbert Xu | 776c729 | 2007-10-14 00:38:32 -0700 | [diff] [blame] | 704 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 705 | } |
Eric Dumazet | 4bc2f18 | 2010-07-09 21:22:10 +0000 | [diff] [blame] | 706 | EXPORT_SYMBOL(ip_defrag); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 707 | |
Eric Dumazet | bc416d9 | 2011-10-06 10:28:31 +0000 | [diff] [blame] | 708 | struct sk_buff *ip_check_defrag(struct sk_buff *skb, u32 user) |
| 709 | { |
| 710 | const struct iphdr *iph; |
| 711 | u32 len; |
| 712 | |
| 713 | if (skb->protocol != htons(ETH_P_IP)) |
| 714 | return skb; |
| 715 | |
| 716 | if (!pskb_may_pull(skb, sizeof(struct iphdr))) |
| 717 | return skb; |
| 718 | |
| 719 | iph = ip_hdr(skb); |
| 720 | if (iph->ihl < 5 || iph->version != 4) |
| 721 | return skb; |
| 722 | if (!pskb_may_pull(skb, iph->ihl*4)) |
| 723 | return skb; |
| 724 | iph = ip_hdr(skb); |
| 725 | len = ntohs(iph->tot_len); |
| 726 | if (skb->len < len || len < (iph->ihl * 4)) |
| 727 | return skb; |
| 728 | |
| 729 | if (ip_is_fragment(ip_hdr(skb))) { |
| 730 | skb = skb_share_check(skb, GFP_ATOMIC); |
| 731 | if (skb) { |
| 732 | if (pskb_trim_rcsum(skb, len)) |
| 733 | return skb; |
| 734 | memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); |
| 735 | if (ip_defrag(skb, user)) |
| 736 | return NULL; |
| 737 | skb->rxhash = 0; |
| 738 | } |
| 739 | } |
| 740 | return skb; |
| 741 | } |
| 742 | EXPORT_SYMBOL(ip_check_defrag); |
| 743 | |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 744 | #ifdef CONFIG_SYSCTL |
| 745 | static int zero; |
| 746 | |
Pavel Emelyanov | 0a64b4b | 2008-05-19 13:51:29 -0700 | [diff] [blame] | 747 | static struct ctl_table ip4_frags_ns_ctl_table[] = { |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 748 | { |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 749 | .procname = "ipfrag_high_thresh", |
Pavel Emelyanov | e31e0bdc7 | 2008-01-22 06:10:13 -0800 | [diff] [blame] | 750 | .data = &init_net.ipv4.frags.high_thresh, |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 751 | .maxlen = sizeof(int), |
| 752 | .mode = 0644, |
Alexey Dobriyan | 6d9f239 | 2008-11-03 18:21:05 -0800 | [diff] [blame] | 753 | .proc_handler = proc_dointvec |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 754 | }, |
| 755 | { |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 756 | .procname = "ipfrag_low_thresh", |
Pavel Emelyanov | e31e0bdc7 | 2008-01-22 06:10:13 -0800 | [diff] [blame] | 757 | .data = &init_net.ipv4.frags.low_thresh, |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 758 | .maxlen = sizeof(int), |
| 759 | .mode = 0644, |
Alexey Dobriyan | 6d9f239 | 2008-11-03 18:21:05 -0800 | [diff] [blame] | 760 | .proc_handler = proc_dointvec |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 761 | }, |
| 762 | { |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 763 | .procname = "ipfrag_time", |
Pavel Emelyanov | b2fd532 | 2008-01-22 06:09:37 -0800 | [diff] [blame] | 764 | .data = &init_net.ipv4.frags.timeout, |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 765 | .maxlen = sizeof(int), |
| 766 | .mode = 0644, |
Alexey Dobriyan | 6d9f239 | 2008-11-03 18:21:05 -0800 | [diff] [blame] | 767 | .proc_handler = proc_dointvec_jiffies, |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 768 | }, |
Pavel Emelyanov | 7d291eb | 2008-05-19 13:53:02 -0700 | [diff] [blame] | 769 | { } |
| 770 | }; |
| 771 | |
| 772 | static struct ctl_table ip4_frags_ctl_table[] = { |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 773 | { |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 774 | .procname = "ipfrag_secret_interval", |
Pavel Emelyanov | 3b4bc4a | 2008-01-22 06:11:04 -0800 | [diff] [blame] | 775 | .data = &ip4_frags.secret_interval, |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 776 | .maxlen = sizeof(int), |
| 777 | .mode = 0644, |
Alexey Dobriyan | 6d9f239 | 2008-11-03 18:21:05 -0800 | [diff] [blame] | 778 | .proc_handler = proc_dointvec_jiffies, |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 779 | }, |
| 780 | { |
| 781 | .procname = "ipfrag_max_dist", |
| 782 | .data = &sysctl_ipfrag_max_dist, |
| 783 | .maxlen = sizeof(int), |
| 784 | .mode = 0644, |
Alexey Dobriyan | 6d9f239 | 2008-11-03 18:21:05 -0800 | [diff] [blame] | 785 | .proc_handler = proc_dointvec_minmax, |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 786 | .extra1 = &zero |
| 787 | }, |
| 788 | { } |
| 789 | }; |
| 790 | |
Alexey Dobriyan | 2c8c1e7 | 2010-01-17 03:35:32 +0000 | [diff] [blame] | 791 | static int __net_init ip4_frags_ns_ctl_register(struct net *net) |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 792 | { |
Pavel Emelyanov | e4a2d5c | 2008-01-22 06:08:36 -0800 | [diff] [blame] | 793 | struct ctl_table *table; |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 794 | struct ctl_table_header *hdr; |
| 795 | |
Pavel Emelyanov | 0a64b4b | 2008-05-19 13:51:29 -0700 | [diff] [blame] | 796 | table = ip4_frags_ns_ctl_table; |
Octavian Purdila | 09ad9bc | 2009-11-25 15:14:13 -0800 | [diff] [blame] | 797 | if (!net_eq(net, &init_net)) { |
Pavel Emelyanov | 0a64b4b | 2008-05-19 13:51:29 -0700 | [diff] [blame] | 798 | table = kmemdup(table, sizeof(ip4_frags_ns_ctl_table), GFP_KERNEL); |
Pavel Emelyanov | e4a2d5c | 2008-01-22 06:08:36 -0800 | [diff] [blame] | 799 | if (table == NULL) |
| 800 | goto err_alloc; |
| 801 | |
Pavel Emelyanov | e31e0bdc7 | 2008-01-22 06:10:13 -0800 | [diff] [blame] | 802 | table[0].data = &net->ipv4.frags.high_thresh; |
| 803 | table[1].data = &net->ipv4.frags.low_thresh; |
Pavel Emelyanov | b2fd532 | 2008-01-22 06:09:37 -0800 | [diff] [blame] | 804 | table[2].data = &net->ipv4.frags.timeout; |
Pavel Emelyanov | e4a2d5c | 2008-01-22 06:08:36 -0800 | [diff] [blame] | 805 | } |
| 806 | |
Eric W. Biederman | ec8f23c | 2012-04-19 13:44:49 +0000 | [diff] [blame] | 807 | hdr = register_net_sysctl(net, "net/ipv4", table); |
Pavel Emelyanov | e4a2d5c | 2008-01-22 06:08:36 -0800 | [diff] [blame] | 808 | if (hdr == NULL) |
| 809 | goto err_reg; |
| 810 | |
| 811 | net->ipv4.frags_hdr = hdr; |
| 812 | return 0; |
| 813 | |
| 814 | err_reg: |
Octavian Purdila | 09ad9bc | 2009-11-25 15:14:13 -0800 | [diff] [blame] | 815 | if (!net_eq(net, &init_net)) |
Pavel Emelyanov | e4a2d5c | 2008-01-22 06:08:36 -0800 | [diff] [blame] | 816 | kfree(table); |
| 817 | err_alloc: |
| 818 | return -ENOMEM; |
| 819 | } |
| 820 | |
Alexey Dobriyan | 2c8c1e7 | 2010-01-17 03:35:32 +0000 | [diff] [blame] | 821 | static void __net_exit ip4_frags_ns_ctl_unregister(struct net *net) |
Pavel Emelyanov | e4a2d5c | 2008-01-22 06:08:36 -0800 | [diff] [blame] | 822 | { |
| 823 | struct ctl_table *table; |
| 824 | |
| 825 | table = net->ipv4.frags_hdr->ctl_table_arg; |
| 826 | unregister_net_sysctl_table(net->ipv4.frags_hdr); |
| 827 | kfree(table); |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 828 | } |
Pavel Emelyanov | 7d291eb | 2008-05-19 13:53:02 -0700 | [diff] [blame] | 829 | |
| 830 | static void ip4_frags_ctl_register(void) |
| 831 | { |
Eric W. Biederman | 4344475 | 2012-04-19 13:22:55 +0000 | [diff] [blame] | 832 | register_net_sysctl(&init_net, "net/ipv4", ip4_frags_ctl_table); |
Pavel Emelyanov | 7d291eb | 2008-05-19 13:53:02 -0700 | [diff] [blame] | 833 | } |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 834 | #else |
Pavel Emelyanov | 0a64b4b | 2008-05-19 13:51:29 -0700 | [diff] [blame] | 835 | static inline int ip4_frags_ns_ctl_register(struct net *net) |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 836 | { |
| 837 | return 0; |
| 838 | } |
Pavel Emelyanov | e4a2d5c | 2008-01-22 06:08:36 -0800 | [diff] [blame] | 839 | |
Pavel Emelyanov | 0a64b4b | 2008-05-19 13:51:29 -0700 | [diff] [blame] | 840 | static inline void ip4_frags_ns_ctl_unregister(struct net *net) |
Pavel Emelyanov | e4a2d5c | 2008-01-22 06:08:36 -0800 | [diff] [blame] | 841 | { |
| 842 | } |
Pavel Emelyanov | 7d291eb | 2008-05-19 13:53:02 -0700 | [diff] [blame] | 843 | |
| 844 | static inline void ip4_frags_ctl_register(void) |
| 845 | { |
| 846 | } |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 847 | #endif |
| 848 | |
Alexey Dobriyan | 2c8c1e7 | 2010-01-17 03:35:32 +0000 | [diff] [blame] | 849 | static int __net_init ipv4_frags_init_net(struct net *net) |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 850 | { |
Pavel Emelyanov | b2fd532 | 2008-01-22 06:09:37 -0800 | [diff] [blame] | 851 | /* |
Pavel Emelyanov | e31e0bdc7 | 2008-01-22 06:10:13 -0800 | [diff] [blame] | 852 | * Fragment cache limits. We will commit 256K at one time. Should we |
| 853 | * cross that limit we will prune down to 192K. This should cope with |
| 854 | * even the most extreme cases without allowing an attacker to |
| 855 | * measurably harm machine performance. |
| 856 | */ |
| 857 | net->ipv4.frags.high_thresh = 256 * 1024; |
| 858 | net->ipv4.frags.low_thresh = 192 * 1024; |
| 859 | /* |
Pavel Emelyanov | b2fd532 | 2008-01-22 06:09:37 -0800 | [diff] [blame] | 860 | * Important NOTE! Fragment queue must be destroyed before MSL expires. |
| 861 | * RFC791 is wrong proposing to prolongate timer each fragment arrival |
| 862 | * by TTL. |
| 863 | */ |
| 864 | net->ipv4.frags.timeout = IP_FRAG_TIME; |
| 865 | |
Pavel Emelyanov | e5a2bb8 | 2008-01-22 06:06:23 -0800 | [diff] [blame] | 866 | inet_frags_init_net(&net->ipv4.frags); |
| 867 | |
Pavel Emelyanov | 0a64b4b | 2008-05-19 13:51:29 -0700 | [diff] [blame] | 868 | return ip4_frags_ns_ctl_register(net); |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 869 | } |
| 870 | |
Alexey Dobriyan | 2c8c1e7 | 2010-01-17 03:35:32 +0000 | [diff] [blame] | 871 | static void __net_exit ipv4_frags_exit_net(struct net *net) |
Pavel Emelyanov | 81566e8 | 2008-01-22 06:12:39 -0800 | [diff] [blame] | 872 | { |
Pavel Emelyanov | 0a64b4b | 2008-05-19 13:51:29 -0700 | [diff] [blame] | 873 | ip4_frags_ns_ctl_unregister(net); |
Pavel Emelyanov | 81566e8 | 2008-01-22 06:12:39 -0800 | [diff] [blame] | 874 | inet_frags_exit_net(&net->ipv4.frags, &ip4_frags); |
| 875 | } |
| 876 | |
| 877 | static struct pernet_operations ip4_frags_ops = { |
| 878 | .init = ipv4_frags_init_net, |
| 879 | .exit = ipv4_frags_exit_net, |
| 880 | }; |
| 881 | |
Eric Dumazet | b7aa0bf | 2007-04-19 16:16:32 -0700 | [diff] [blame] | 882 | void __init ipfrag_init(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 883 | { |
Pavel Emelyanov | 7d291eb | 2008-05-19 13:53:02 -0700 | [diff] [blame] | 884 | ip4_frags_ctl_register(); |
Pavel Emelyanov | 81566e8 | 2008-01-22 06:12:39 -0800 | [diff] [blame] | 885 | register_pernet_subsys(&ip4_frags_ops); |
Pavel Emelyanov | 321a3a9 | 2007-10-15 02:38:08 -0700 | [diff] [blame] | 886 | ip4_frags.hashfn = ip4_hashfn; |
Pavel Emelyanov | c6fda28 | 2007-10-17 19:46:47 -0700 | [diff] [blame] | 887 | ip4_frags.constructor = ip4_frag_init; |
Pavel Emelyanov | 1e4b828 | 2007-10-15 02:39:14 -0700 | [diff] [blame] | 888 | ip4_frags.destructor = ip4_frag_free; |
| 889 | ip4_frags.skb_free = NULL; |
| 890 | ip4_frags.qsize = sizeof(struct ipq); |
Pavel Emelyanov | abd6523 | 2007-10-17 19:47:21 -0700 | [diff] [blame] | 891 | ip4_frags.match = ip4_frag_match; |
Pavel Emelyanov | e521db9 | 2007-10-17 19:45:23 -0700 | [diff] [blame] | 892 | ip4_frags.frag_expire = ip_expire; |
Pavel Emelyanov | 3b4bc4a | 2008-01-22 06:11:04 -0800 | [diff] [blame] | 893 | ip4_frags.secret_interval = 10 * 60 * HZ; |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 894 | inet_frags_init(&ip4_frags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 895 | } |