From 2b246b2569cd2ac6ff700d0dce56b8bae29b1842 Mon Sep 17 00:00:00 2001 From: Andreas Roeseler Date: Mon, 29 Mar 2021 18:45:15 -0700 Subject: icmp: add support for RFC 8335 PROBE Add definitions for PROBE ICMP types and codes. Add AFI definitions for IP and IPV6 as specified by IANA Add a struct to represent the additional header when probing by IP address (ctype == 3) for use in parsing incoming PROBE messages Add a struct to represent the entire Interface Identification Object (IIO) section of an incoming PROBE packet Signed-off-by: Andreas Roeseler Signed-off-by: David S. Miller --- include/uapi/linux/icmp.h | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) (limited to 'include') diff --git a/include/uapi/linux/icmp.h b/include/uapi/linux/icmp.h index fb169a50895e..222325d1d80e 100644 --- a/include/uapi/linux/icmp.h +++ b/include/uapi/linux/icmp.h @@ -20,6 +20,9 @@ #include #include +#include +#include +#include #define ICMP_ECHOREPLY 0 /* Echo Reply */ #define ICMP_DEST_UNREACH 3 /* Destination Unreachable */ @@ -66,6 +69,23 @@ #define ICMP_EXC_TTL 0 /* TTL count exceeded */ #define ICMP_EXC_FRAGTIME 1 /* Fragment Reass time exceeded */ +/* Codes for EXT_ECHO (PROBE) */ +#define ICMP_EXT_ECHO 42 +#define ICMP_EXT_ECHOREPLY 43 +#define ICMP_EXT_MAL_QUERY 1 /* Malformed Query */ +#define ICMP_EXT_NO_IF 2 /* No such Interface */ +#define ICMP_EXT_NO_TABLE_ENT 3 /* No such Table Entry */ +#define ICMP_EXT_MULT_IFS 4 /* Multiple Interfaces Satisfy Query */ + +/* Constants for EXT_ECHO (PROBE) */ +#define EXT_ECHOREPLY_ACTIVE (1 << 2)/* active bit in reply message */ +#define EXT_ECHOREPLY_IPV4 (1 << 1)/* ipv4 bit in reply message */ +#define EXT_ECHOREPLY_IPV6 1 /* ipv6 bit in reply message */ +#define EXT_ECHO_CTYPE_NAME 1 +#define EXT_ECHO_CTYPE_INDEX 2 +#define EXT_ECHO_CTYPE_ADDR 3 +#define ICMP_AFI_IP 1 /* Address Family Identifier for ipv4 */ +#define ICMP_AFI_IP6 2 /* Address Family Identifier for ipv6 */ struct icmphdr { __u8 type; @@ -118,4 +138,26 @@ struct icmp_extobj_hdr { __u8 class_type; }; +/* RFC 8335: 2.1 Header for c-type 3 payload */ +struct icmp_ext_echo_ctype3_hdr { + __be16 afi; + __u8 addrlen; + __u8 reserved; +}; + +/* RFC 8335: 2.1 Interface Identification Object */ +struct icmp_ext_echo_iio { + struct icmp_extobj_hdr extobj_hdr; + union { + char name[IFNAMSIZ]; + __be32 ifindex; + struct { + struct icmp_ext_echo_ctype3_hdr ctype3_hdr; + union { + struct in_addr ipv4_addr; + struct in6_addr ipv6_addr; + } ip_addr; + } addr; + } ident; +}; #endif /* _UAPI_LINUX_ICMP_H */ -- cgit v1.2.3 From 750f4fc2a12f6632b5aa04526bf57fa06bfe8467 Mon Sep 17 00:00:00 2001 From: Andreas Roeseler Date: Mon, 29 Mar 2021 18:45:21 -0700 Subject: ICMPV6: add support for RFC 8335 PROBE Add definitions for the ICMPV6 type of Extended Echo Request and Extended Echo Reply, as defined by sections 2 and 3 of RFC 8335. Signed-off-by: Andreas Roeseler Signed-off-by: David S. Miller --- include/uapi/linux/icmpv6.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include') diff --git a/include/uapi/linux/icmpv6.h b/include/uapi/linux/icmpv6.h index 0564fd7ccde4..ecaece3af38d 100644 --- a/include/uapi/linux/icmpv6.h +++ b/include/uapi/linux/icmpv6.h @@ -140,6 +140,9 @@ struct icmp6hdr { #define ICMPV6_UNK_OPTION 2 #define ICMPV6_HDR_INCOMP 3 +/* Codes for EXT_ECHO (PROBE) */ +#define ICMPV6_EXT_ECHO_REQUEST 160 +#define ICMPV6_EXT_ECHO_REPLY 161 /* * constants for (set|get)sockopt */ -- cgit v1.2.3 From f1b8fa9fa5865c58c093cde6d782104c22df9088 Mon Sep 17 00:00:00 2001 From: Andreas Roeseler Date: Mon, 29 Mar 2021 18:45:29 -0700 Subject: net: add sysctl for enabling RFC 8335 PROBE messages Section 8 of RFC 8335 specifies potential security concerns of responding to PROBE requests, and states that nodes that support PROBE functionality MUST be able to enable/disable responses and that responses MUST be disabled by default Signed-off-by: Andreas Roeseler Signed-off-by: David S. Miller --- Documentation/networking/ip-sysctl.rst | 6 ++++++ include/net/netns/ipv4.h | 1 + net/ipv4/sysctl_net_ipv4.c | 9 +++++++++ 3 files changed, 16 insertions(+) (limited to 'include') diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst index c7952ac5bd2f..4130bce40765 100644 --- a/Documentation/networking/ip-sysctl.rst +++ b/Documentation/networking/ip-sysctl.rst @@ -1143,6 +1143,12 @@ icmp_echo_ignore_all - BOOLEAN Default: 0 +icmp_echo_enable_probe - BOOLEAN + If set to one, then the kernel will respond to RFC 8335 PROBE + requests sent to it. + + Default: 0 + icmp_echo_ignore_broadcasts - BOOLEAN If set non-zero, then the kernel will ignore all ICMP ECHO and TIMESTAMP requests sent to it via broadcast/multicast. diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h index d377266d133f..9c8dd424d79b 100644 --- a/include/net/netns/ipv4.h +++ b/include/net/netns/ipv4.h @@ -84,6 +84,7 @@ struct netns_ipv4 { #endif u8 sysctl_icmp_echo_ignore_all; + u8 sysctl_icmp_echo_enable_probe; u8 sysctl_icmp_echo_ignore_broadcasts; u8 sysctl_icmp_ignore_bogus_error_responses; u8 sysctl_icmp_errors_use_inbound_ifaddr; diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c index 3a7e5cf5d6cc..e3cb2d96b55e 100644 --- a/net/ipv4/sysctl_net_ipv4.c +++ b/net/ipv4/sysctl_net_ipv4.c @@ -598,6 +598,15 @@ static struct ctl_table ipv4_net_table[] = { .mode = 0644, .proc_handler = proc_dou8vec_minmax, }, + { + .procname = "icmp_echo_enable_probe", + .data = &init_net.ipv4.sysctl_icmp_echo_enable_probe, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE + }, { .procname = "icmp_echo_ignore_broadcasts", .data = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts, -- cgit v1.2.3 From 504a40113cc4f329dd75bbf6e4b060603224d814 Mon Sep 17 00:00:00 2001 From: Andreas Roeseler Date: Mon, 29 Mar 2021 18:45:43 -0700 Subject: ipv6: add ipv6_dev_find to stubs Add ipv6_dev_find to ipv6_stub to allow lookup of net_devices by IPV6 address in net/ipv4/icmp.c. Signed-off-by: Andreas Roeseler Signed-off-by: David S. Miller --- include/net/ipv6_stubs.h | 2 ++ net/ipv6/addrconf_core.c | 7 +++++++ net/ipv6/af_inet6.c | 1 + 3 files changed, 10 insertions(+) (limited to 'include') diff --git a/include/net/ipv6_stubs.h b/include/net/ipv6_stubs.h index 8fce558b5fea..afbce90c4480 100644 --- a/include/net/ipv6_stubs.h +++ b/include/net/ipv6_stubs.h @@ -66,6 +66,8 @@ struct ipv6_stub { int (*ipv6_fragment)(struct net *net, struct sock *sk, struct sk_buff *skb, int (*output)(struct net *, struct sock *, struct sk_buff *)); + struct net_device *(*ipv6_dev_find)(struct net *net, const struct in6_addr *addr, + struct net_device *dev); }; extern const struct ipv6_stub *ipv6_stub __read_mostly; diff --git a/net/ipv6/addrconf_core.c b/net/ipv6/addrconf_core.c index a36626afbc02..1d4054bb345b 100644 --- a/net/ipv6/addrconf_core.c +++ b/net/ipv6/addrconf_core.c @@ -198,6 +198,12 @@ static int eafnosupport_ipv6_fragment(struct net *net, struct sock *sk, struct s return -EAFNOSUPPORT; } +static struct net_device *eafnosupport_ipv6_dev_find(struct net *net, const struct in6_addr *addr, + struct net_device *dev) +{ + return ERR_PTR(-EAFNOSUPPORT); +} + const struct ipv6_stub *ipv6_stub __read_mostly = &(struct ipv6_stub) { .ipv6_dst_lookup_flow = eafnosupport_ipv6_dst_lookup_flow, .ipv6_route_input = eafnosupport_ipv6_route_input, @@ -209,6 +215,7 @@ const struct ipv6_stub *ipv6_stub __read_mostly = &(struct ipv6_stub) { .fib6_nh_init = eafnosupport_fib6_nh_init, .ip6_del_rt = eafnosupport_ip6_del_rt, .ipv6_fragment = eafnosupport_ipv6_fragment, + .ipv6_dev_find = eafnosupport_ipv6_dev_find, }; EXPORT_SYMBOL_GPL(ipv6_stub); diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index 3c9bacffc9c3..4f7ca5807046 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -1032,6 +1032,7 @@ static const struct ipv6_stub ipv6_stub_impl = { #endif .nd_tbl = &nd_tbl, .ipv6_fragment = ip6_fragment, + .ipv6_dev_find = ipv6_dev_find, }; static const struct ipv6_bpf_stub ipv6_bpf_stub_impl = { -- cgit v1.2.3