cregit-Linux how code gets into the kernel

Release 4.8 net/sched/act_csum.c

Directory: net/sched
/*
 * Checksum updating actions
 *
 * Copyright (c) 2010 Gregoire Baron <baronchon@n7mm.org>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 *
 */

#include <linux/types.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/spinlock.h>

#include <linux/netlink.h>
#include <net/netlink.h>
#include <linux/rtnetlink.h>

#include <linux/skbuff.h>

#include <net/ip.h>
#include <net/ipv6.h>
#include <net/icmp.h>
#include <linux/icmpv6.h>
#include <linux/igmp.h>
#include <net/tcp.h>
#include <net/udp.h>
#include <net/ip6_checksum.h>

#include <net/act_api.h>

#include <linux/tc_act/tc_csum.h>
#include <net/tc_act/tc_csum.h>


#define CSUM_TAB_MASK 15


static const struct nla_policy csum_policy[TCA_CSUM_MAX + 1] = {
	[TCA_CSUM_PARMS] = { .len = sizeof(struct tc_csum), },
};


static int csum_net_id;

static struct tc_action_ops act_csum_ops;


static int tcf_csum_init(struct net *net, struct nlattr *nla, struct nlattr *est, struct tc_action **a, int ovr, int bind) { struct tc_action_net *tn = net_generic(net, csum_net_id); struct nlattr *tb[TCA_CSUM_MAX + 1]; struct tc_csum *parm; struct tcf_csum *p; int ret = 0, err; if (nla == NULL) return -EINVAL; err = nla_parse_nested(tb, TCA_CSUM_MAX, nla, csum_policy); if (err < 0) return err; if (tb[TCA_CSUM_PARMS] == NULL) return -EINVAL; parm = nla_data(tb[TCA_CSUM_PARMS]); if (!tcf_hash_check(tn, parm->index, a, bind)) { ret = tcf_hash_create(tn, parm->index, est, a, &act_csum_ops, bind, false); if (ret) return ret; ret = ACT_P_CREATED; } else { if (bind)/* dont override defaults */ return 0; tcf_hash_release(*a, bind); if (!ovr) return -EEXIST; } p = to_tcf_csum(*a); spin_lock_bh(&p->tcf_lock); p->tcf_action = parm->action; p->update_flags = parm->update_flags; spin_unlock_bh(&p->tcf_lock); if (ret == ACT_P_CREATED) tcf_hash_insert(tn, *a); return ret; }

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gregoire barongregoire baron20778.71%112.50%
americo wangamerico wang3412.93%450.00%
jamal hadi salimjamal hadi salim166.08%112.50%
benjamin lahaisebenjamin lahaise41.52%112.50%
eric dumazeteric dumazet20.76%112.50%
Total263100.00%8100.00%

/** * tcf_csum_skb_nextlayer - Get next layer pointer * @skb: sk_buff to use * @ihl: previous summed headers length * @ipl: complete packet length * @jhl: next header length * * Check the expected next layer availability in the specified sk_buff. * Return the next layer pointer if pass, NULL otherwise. */
static void *tcf_csum_skb_nextlayer(struct sk_buff *skb, unsigned int ihl, unsigned int ipl, unsigned int jhl) { int ntkoff = skb_network_offset(skb); int hl = ihl + jhl; if (!pskb_may_pull(skb, ipl + ntkoff) || (ipl < hl) || skb_try_make_writable(skb, hl + ntkoff)) return NULL; else return (void *)(skb_network_header(skb) + ihl); }

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gregoire barongregoire baron8398.81%150.00%
daniel borkmanndaniel borkmann11.19%150.00%
Total84100.00%2100.00%


static int tcf_csum_ipv4_icmp(struct sk_buff *skb, unsigned int ihl, unsigned int ipl) { struct icmphdr *icmph; icmph = tcf_csum_skb_nextlayer(skb, ihl, ipl, sizeof(*icmph)); if (icmph == NULL) return 0; icmph->checksum = 0; skb->csum = csum_partial(icmph, ipl - ihl, 0); icmph->checksum = csum_fold(skb->csum); skb->ip_summed = CHECKSUM_NONE; return 1; }

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gregoire barongregoire baron91100.00%1100.00%
Total91100.00%1100.00%


static int tcf_csum_ipv4_igmp(struct sk_buff *skb, unsigned int ihl, unsigned int ipl) { struct igmphdr *igmph; igmph = tcf_csum_skb_nextlayer(skb, ihl, ipl, sizeof(*igmph)); if (igmph == NULL) return 0; igmph->csum = 0; skb->csum = csum_partial(igmph, ipl - ihl, 0); igmph->csum = csum_fold(skb->csum); skb->ip_summed = CHECKSUM_NONE; return 1; }

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gregoire barongregoire baron91100.00%1100.00%
Total91100.00%1100.00%


static int tcf_csum_ipv6_icmp(struct sk_buff *skb, unsigned int ihl, unsigned int ipl) { struct icmp6hdr *icmp6h; const struct ipv6hdr *ip6h; icmp6h = tcf_csum_skb_nextlayer(skb, ihl, ipl, sizeof(*icmp6h)); if (icmp6h == NULL) return 0; ip6h = ipv6_hdr(skb); icmp6h->icmp6_cksum = 0; skb->csum = csum_partial(icmp6h, ipl - ihl, 0); icmp6h->icmp6_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, ipl - ihl, IPPROTO_ICMPV6, skb->csum); skb->ip_summed = CHECKSUM_NONE; return 1; }

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gregoire barongregoire baron10789.17%150.00%
eric dumazeteric dumazet1310.83%150.00%
Total120100.00%2100.00%


static int tcf_csum_ipv4_tcp(struct sk_buff *skb, unsigned int ihl, unsigned int ipl) { struct tcphdr *tcph; const struct iphdr *iph; tcph = tcf_csum_skb_nextlayer(skb, ihl, ipl, sizeof(*tcph)); if (tcph == NULL) return 0; iph = ip_hdr(skb); tcph->check = 0; skb->csum = csum_partial(tcph, ipl - ihl, 0); tcph->check = tcp_v4_check(ipl - ihl, iph->saddr, iph->daddr, skb->csum); skb->ip_summed = CHECKSUM_NONE; return 1; }

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gregoire barongregoire baron10388.79%150.00%
eric dumazeteric dumazet1311.21%150.00%
Total116100.00%2100.00%


static int tcf_csum_ipv6_tcp(struct sk_buff *skb, unsigned int ihl, unsigned int ipl) { struct tcphdr *tcph; const struct ipv6hdr *ip6h; tcph = tcf_csum_skb_nextlayer(skb, ihl, ipl, sizeof(*tcph)); if (tcph == NULL) return 0; ip6h = ipv6_hdr(skb); tcph->check = 0; skb->csum = csum_partial(tcph, ipl - ihl, 0); tcph->check = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, ipl - ihl, IPPROTO_TCP, skb->csum); skb->ip_summed = CHECKSUM_NONE; return 1; }

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gregoire barongregoire baron10789.17%150.00%
eric dumazeteric dumazet1310.83%150.00%
Total120100.00%2100.00%


static int tcf_csum_ipv4_udp(struct sk_buff *skb, unsigned int ihl, unsigned int ipl, int udplite) { struct udphdr *udph; const struct iphdr *iph; u16 ul; /* * Support both UDP and UDPLITE checksum algorithms, Don't use * udph->len to get the real length without any protocol check, * UDPLITE uses udph->len for another thing, * Use iph->tot_len, or just ipl. */ udph = tcf_csum_skb_nextlayer(skb, ihl, ipl, sizeof(*udph)); if (udph == NULL) return 0; iph = ip_hdr(skb); ul = ntohs(udph->len); if (udplite || udph->check) { udph->check = 0; if (udplite) { if (ul == 0) skb->csum = csum_partial(udph, ipl - ihl, 0); else if ((ul >= sizeof(*udph)) && (ul <= ipl - ihl)) skb->csum = csum_partial(udph, ul, 0); else goto ignore_obscure_skb; } else { if (ul != ipl - ihl) goto ignore_obscure_skb; skb->csum = csum_partial(udph, ul, 0); } udph->check = csum_tcpudp_magic(iph->saddr, iph->daddr, ul, iph->protocol, skb->csum); if (!udph->check) udph->check = CSUM_MANGLED_0; } skb->ip_summed = CHECKSUM_NONE; ignore_obscure_skb: return 1; }

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gregoire barongregoire baron22294.07%133.33%
eric dumazeteric dumazet135.51%133.33%
changli gaochangli gao10.42%133.33%
Total236100.00%3100.00%


static int tcf_csum_ipv6_udp(struct sk_buff *skb, unsigned int ihl, unsigned int ipl, int udplite) { struct udphdr *udph; const struct ipv6hdr *ip6h; u16 ul; /* * Support both UDP and UDPLITE checksum algorithms, Don't use * udph->len to get the real length without any protocol check, * UDPLITE uses udph->len for another thing, * Use ip6h->payload_len + sizeof(*ip6h) ... , or just ipl. */ udph = tcf_csum_skb_nextlayer(skb, ihl, ipl, sizeof(*udph)); if (udph == NULL) return 0; ip6h = ipv6_hdr(skb); ul = ntohs(udph->len); udph->check = 0; if (udplite) { if (ul == 0) skb->csum = csum_partial(udph, ipl - ihl, 0); else if ((ul >= sizeof(*udph)) && (ul <= ipl - ihl)) skb->csum = csum_partial(udph, ul, 0); else goto ignore_obscure_skb; } else { if (ul != ipl - ihl) goto ignore_obscure_skb; skb->csum = csum_partial(udph, ul, 0); } udph->check = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, ul, udplite ? IPPROTO_UDPLITE : IPPROTO_UDP, skb->csum); if (!udph->check) udph->check = CSUM_MANGLED_0; skb->ip_summed = CHECKSUM_NONE; ignore_obscure_skb: return 1; }

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gregoire barongregoire baron21693.91%133.33%
eric dumazeteric dumazet135.65%133.33%
changli gaochangli gao10.43%133.33%
Total230100.00%3100.00%


static int tcf_csum_ipv4(struct sk_buff *skb, u32 update_flags) { const struct iphdr *iph; int ntkoff; ntkoff = skb_network_offset(skb); if (!pskb_may_pull(skb, sizeof(*iph) + ntkoff)) goto fail; iph = ip_hdr(skb); switch (iph->frag_off & htons(IP_OFFSET) ? 0 : iph->protocol) { case IPPROTO_ICMP: if (update_flags & TCA_CSUM_UPDATE_FLAG_ICMP) if (!tcf_csum_ipv4_icmp(skb, iph->ihl * 4, ntohs(iph->tot_len))) goto fail; break; case IPPROTO_IGMP: if (update_flags & TCA_CSUM_UPDATE_FLAG_IGMP) if (!tcf_csum_ipv4_igmp(skb, iph->ihl * 4, ntohs(iph->tot_len))) goto fail; break; case IPPROTO_TCP: if (update_flags & TCA_CSUM_UPDATE_FLAG_TCP) if (!tcf_csum_ipv4_tcp(skb, iph->ihl * 4, ntohs(iph->tot_len))) goto fail; break; case IPPROTO_UDP: if (update_flags & TCA_CSUM_UPDATE_FLAG_UDP) if (!tcf_csum_ipv4_udp(skb, iph->ihl * 4, ntohs(iph->tot_len), 0)) goto fail; break; case IPPROTO_UDPLITE: if (update_flags & TCA_CSUM_UPDATE_FLAG_UDPLITE) if (!tcf_csum_ipv4_udp(skb, iph->ihl * 4, ntohs(iph->tot_len), 1)) goto fail; break; } if (update_flags & TCA_CSUM_UPDATE_FLAG_IPV4HDR) { if (skb_try_make_writable(skb, sizeof(*iph) + ntkoff)) goto fail; ip_send_check(ip_hdr(skb)); } return 1; fail: return 0; }

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gregoire barongregoire baron28597.94%133.33%
eric dumazeteric dumazet51.72%133.33%
daniel borkmanndaniel borkmann10.34%133.33%
Total291100.00%3100.00%


static int tcf_csum_ipv6_hopopts(struct ipv6_opt_hdr *ip6xh, unsigned int ixhl, unsigned int *pl) { int off, len, optlen; unsigned char *xh = (void *)ip6xh; off = sizeof(*ip6xh); len = ixhl - off; while (len > 1) { switch (xh[off]) { case IPV6_TLV_PAD1: optlen = 1; break; case IPV6_TLV_JUMBO: optlen = xh[off + 1] + 2; if (optlen != 6 || len < 6 || (off & 3) != 2) /* wrong jumbo option length/alignment */ return 0; *pl = ntohl(*(__be32 *)(xh + off + 2)); goto done; default: optlen = xh[off + 1] + 2; if (optlen > len) /* ignore obscure options */ goto done; break; } off += optlen; len -= optlen; } done: return 1; }

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gregoire barongregoire baron17099.42%150.00%
eldad zackeldad zack10.58%150.00%
Total171100.00%2100.00%


static int tcf_csum_ipv6(struct sk_buff *skb, u32 update_flags) { struct ipv6hdr *ip6h; struct ipv6_opt_hdr *ip6xh; unsigned int hl, ixhl; unsigned int pl; int ntkoff; u8 nexthdr; ntkoff = skb_network_offset(skb); hl = sizeof(*ip6h); if (!pskb_may_pull(skb, hl + ntkoff)) goto fail; ip6h = ipv6_hdr(skb); pl = ntohs(ip6h->payload_len); nexthdr = ip6h->nexthdr; do { switch (nexthdr) { case NEXTHDR_FRAGMENT: goto ignore_skb; case NEXTHDR_ROUTING: case NEXTHDR_HOP: case NEXTHDR_DEST: if (!pskb_may_pull(skb, hl + sizeof(*ip6xh) + ntkoff)) goto fail; ip6xh = (void *)(skb_network_header(skb) + hl); ixhl = ipv6_optlen(ip6xh); if (!pskb_may_pull(skb, hl + ixhl + ntkoff)) goto fail; ip6xh = (void *)(skb_network_header(skb) + hl); if ((nexthdr == NEXTHDR_HOP) && !(tcf_csum_ipv6_hopopts(ip6xh, ixhl, &pl))) goto fail; nexthdr = ip6xh->nexthdr; hl += ixhl; break; case IPPROTO_ICMPV6: if (update_flags & TCA_CSUM_UPDATE_FLAG_ICMP) if (!tcf_csum_ipv6_icmp(skb, hl, pl + sizeof(*ip6h))) goto fail; goto done; case IPPROTO_TCP: if (update_flags & TCA_CSUM_UPDATE_FLAG_TCP) if (!tcf_csum_ipv6_tcp(skb, hl, pl + sizeof(*ip6h))) goto fail; goto done; case IPPROTO_UDP: if (update_flags & TCA_CSUM_UPDATE_FLAG_UDP) if (!tcf_csum_ipv6_udp(skb, hl, pl + sizeof(*ip6h), 0)) goto fail; goto done; case IPPROTO_UDPLITE: if (update_flags & TCA_CSUM_UPDATE_FLAG_UDPLITE) if (!tcf_csum_ipv6_udp(skb, hl, pl + sizeof(*ip6h), 1)) goto fail; goto done; default: goto ignore_skb; } } while (pskb_may_pull(skb, hl + 1 + ntkoff)); done: ignore_skb: return 1; fail: return 0; }

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gregoire barongregoire baron37796.17%150.00%
eric dumazeteric dumazet153.83%150.00%
Total392100.00%2100.00%


static int tcf_csum(struct sk_buff *skb, const struct tc_action *a, struct tcf_result *res) { struct tcf_csum *p = to_tcf_csum(a); int action; u32 update_flags; spin_lock(&p->tcf_lock); tcf_lastuse_update(&p->tcf_tm); bstats_update(&p->tcf_bstats, skb); action = p->tcf_action; update_flags = p->update_flags; spin_unlock(&p->tcf_lock); if (unlikely(action == TC_ACT_SHOT)) goto drop; switch (tc_skb_protocol(skb)) { case cpu_to_be16(ETH_P_IP): if (!tcf_csum_ipv4(skb, update_flags)) goto drop; break; case cpu_to_be16(ETH_P_IPV6): if (!tcf_csum_ipv6(skb, update_flags)) goto drop; break; } return action; drop: spin_lock(&p->tcf_lock); p->tcf_qstats.drops++; spin_unlock(&p->tcf_lock); return TC_ACT_SHOT; }

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gregoire barongregoire baron16191.48%116.67%
eric dumazeteric dumazet52.84%233.33%
jamal hadi salimjamal hadi salim42.27%116.67%
jiri pirkojiri pirko31.70%116.67%
americo wangamerico wang31.70%116.67%
Total176100.00%6100.00%


static int tcf_csum_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref) { unsigned char *b = skb_tail_pointer(skb); struct tcf_csum *p = to_tcf_csum(a); struct tc_csum opt = { .update_flags = p->update_flags, .index = p->tcf_index, .action = p->tcf_action, .refcnt = p->tcf_refcnt - ref, .bindcnt = p->tcf_bindcnt - bind, }; struct tcf_t t; if (nla_put(skb, TCA_CSUM_PARMS, sizeof(opt), &opt)) goto nla_put_failure; tcf_tm_dump(&t, &p->tcf_tm); if (nla_put_64bit(skb, TCA_CSUM_TM, sizeof(t), &t, TCA_CSUM_PAD)) goto nla_put_failure; return skb->len; nla_put_failure: nlmsg_trim(skb, b); return -1; }

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gregoire barongregoire baron13885.19%116.67%
david s. millerdavid s. miller138.02%116.67%
jamal hadi salimjamal hadi salim53.09%233.33%
nicolas dichtelnicolas dichtel31.85%116.67%
americo wangamerico wang31.85%116.67%
Total162100.00%6100.00%


static int tcf_csum_walker(struct net *net, struct sk_buff *skb, struct netlink_callback *cb, int type, const struct tc_action_ops *ops) { struct tc_action_net *tn = net_generic(net, csum_net_id); return tcf_generic_walker(tn, skb, cb, type, ops); }

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americo wangamerico wang56100.00%2100.00%
Total56100.00%2100.00%


static int tcf_csum_search(struct net *net, struct tc_action **a, u32 index) { struct tc_action_net *tn = net_generic(net, csum_net_id); return tcf_hash_search(tn, a, index); }

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americo wangamerico wang42100.00%2100.00%
Total42100.00%2100.00%

static struct tc_action_ops act_csum_ops = { .kind = "csum", .type = TCA_ACT_CSUM, .owner = THIS_MODULE, .act = tcf_csum, .dump = tcf_csum_dump, .init = tcf_csum_init, .walk = tcf_csum_walker, .lookup = tcf_csum_search, .size = sizeof(struct tcf_csum), };
static __net_init int csum_init_net(struct net *net) { struct tc_action_net *tn = net_generic(net, csum_net_id); return tc_action_net_init(tn, &act_csum_ops, CSUM_TAB_MASK); }

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americo wangamerico wang35100.00%1100.00%
Total35100.00%1100.00%


static void __net_exit csum_exit_net(struct net *net) { struct