diff options
Diffstat (limited to 'net/ipv4/icmp.c')
| -rw-r--r-- | net/ipv4/icmp.c | 65 |
1 files changed, 42 insertions, 23 deletions
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index 752e392083e6..c695d294a5df 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -993,14 +993,8 @@ static bool icmp_redirect(struct sk_buff *skb) static bool icmp_echo(struct sk_buff *skb) { - struct icmp_ext_hdr *ext_hdr, _ext_hdr; - struct icmp_ext_echo_iio *iio, _iio; struct icmp_bxm icmp_param; - struct net_device *dev; - char buff[IFNAMSIZ]; struct net *net; - u16 ident_len; - u8 status; net = dev_net(skb_dst(skb)->dev); /* should there be an ICMP stat for ignored echos? */ @@ -1013,20 +1007,46 @@ static bool icmp_echo(struct sk_buff *skb) icmp_param.data_len = skb->len; icmp_param.head_len = sizeof(struct icmphdr); - if (icmp_param.data.icmph.type == ICMP_ECHO) { + if (icmp_param.data.icmph.type == ICMP_ECHO) icmp_param.data.icmph.type = ICMP_ECHOREPLY; - goto send_reply; - } - if (!net->ipv4.sysctl_icmp_echo_enable_probe) + else if (!icmp_build_probe(skb, &icmp_param.data.icmph)) return true; + + icmp_reply(&icmp_param, skb); + return true; +} + +/* Helper for icmp_echo and icmpv6_echo_reply. + * Searches for net_device that matches PROBE interface identifier + * and builds PROBE reply message in icmphdr. + * + * Returns false if PROBE responses are disabled via sysctl + */ + +bool icmp_build_probe(struct sk_buff *skb, struct icmphdr *icmphdr) +{ + struct icmp_ext_hdr *ext_hdr, _ext_hdr; + struct icmp_ext_echo_iio *iio, _iio; + struct net *net = dev_net(skb->dev); + struct net_device *dev; + char buff[IFNAMSIZ]; + u16 ident_len; + u8 status; + + if (!net->ipv4.sysctl_icmp_echo_enable_probe) + return false; + /* We currently only support probing interfaces on the proxy node * Check to ensure L-bit is set */ - if (!(ntohs(icmp_param.data.icmph.un.echo.sequence) & 1)) - return true; + if (!(ntohs(icmphdr->un.echo.sequence) & 1)) + return false; /* Clear status bits in reply message */ - icmp_param.data.icmph.un.echo.sequence &= htons(0xFF00); - icmp_param.data.icmph.type = ICMP_EXT_ECHOREPLY; + icmphdr->un.echo.sequence &= htons(0xFF00); + if (icmphdr->type == ICMP_EXT_ECHO) + icmphdr->type = ICMP_EXT_ECHOREPLY; + else + icmphdr->type = ICMPV6_EXT_ECHO_REPLY; ext_hdr = skb_header_pointer(skb, 0, sizeof(_ext_hdr), &_ext_hdr); /* Size of iio is class_type dependent. * Only check header here and assign length based on ctype in the switch statement @@ -1066,7 +1086,7 @@ static bool icmp_echo(struct sk_buff *skb) if (ident_len != sizeof(iio->ident.addr.ctype3_hdr) + sizeof(struct in_addr)) goto send_mal_query; - dev = ip_dev_find(net, iio->ident.addr.ip_addr.ipv4_addr.s_addr); + dev = ip_dev_find(net, iio->ident.addr.ip_addr.ipv4_addr); break; #if IS_ENABLED(CONFIG_IPV6) case ICMP_AFI_IP6: @@ -1087,8 +1107,8 @@ static bool icmp_echo(struct sk_buff *skb) goto send_mal_query; } if (!dev) { - icmp_param.data.icmph.code = ICMP_EXT_CODE_NO_IF; - goto send_reply; + icmphdr->code = ICMP_EXT_CODE_NO_IF; + return true; } /* Fill bits in reply message */ if (dev->flags & IFF_UP) @@ -1098,14 +1118,13 @@ static bool icmp_echo(struct sk_buff *skb) if (!list_empty(&rcu_dereference(dev->ip6_ptr)->addr_list)) status |= ICMP_EXT_ECHOREPLY_IPV6; dev_put(dev); - icmp_param.data.icmph.un.echo.sequence |= htons(status); -send_reply: - icmp_reply(&icmp_param, skb); - return true; + icmphdr->un.echo.sequence |= htons(status); + return true; send_mal_query: - icmp_param.data.icmph.code = ICMP_EXT_CODE_MAL_QUERY; - goto send_reply; + icmphdr->code = ICMP_EXT_CODE_MAL_QUERY; + return true; } +EXPORT_SYMBOL_GPL(icmp_build_probe); /* * Handle ICMP Timestamp requests. |