[PATCH v3 net-next 0/3] add support sending RFC8335 PROBE

[PATCH v3 net-next 0/3] add support sending RFC8335 PROBE

[Andreas Roeseler]

The popular utility ping has several severe limitations such as the
inability to query specific  interfaces on a node and requiring
bidirectional connectivity between the probing and the probed
interfaces. RFC8335 attempts to solve these limitations by creating the
new utility PROBE which is a specialized ICMP message that makes use of
the ICMP Extension Structure outlined in RFC4884.

This patchset adds definitions for the ICMP Extended Echo Request and
Reply (PROBE) types for both IPv4 and IPv6. It also expands the list of
supported ICMP messages to accommodate PROBEs.

Changes since v1:
 - Switch to correct base tree

Changes since v2:
 - Switch to net-next tree 67c70b5eb2bf7d0496fcb62d308dc3096bc11553

Andreas Roeseler (3):
  net: add support for sending RFC8335 PROBE
  icmp: define PROBE message types
  ICMPv6: define PROBE message types

 include/uapi/linux/icmp.h   | 3 +++
 include/uapi/linux/icmpv6.h | 6 ++++++
 net/ipv4/ping.c             | 4 +++-
 3 files changed, 12 insertions(+), 1 deletion(-)

-- 
2.29.2

[PATCH v3 net-next 1/3] net: add support for sending RFC8335 PROBE

[Andreas Roeseler]

Modifying the ping_supported function to support probe message types
allows the user to send probe requests through the existing framework
for sending ping requests.

Signed-off-by: Andreas Roeseler <andreas.a.roeseler@gmail.com>
---
Changes since v1:
 - Switch to correct base tree

Changes since v2:
 - Switch to net-next tree 67c70b5eb2bf7d0496fcb62d308dc3096bc11553
---
 net/ipv4/ping.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index 248856b301c4..39bdcb2bfc92 100644
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -453,7 +453,9 @@ EXPORT_SYMBOL_GPL(ping_bind);
 static inline int ping_supported(int family, int type, int code)
 {
 	return (family == AF_INET && type == ICMP_ECHO && code == 0) ||
-	       (family == AF_INET6 && type == ICMPV6_ECHO_REQUEST && code == 0);
+	       (family == AF_INET && type == ICMP_EXT_ECHO && code == 0) ||
+	       (family == AF_INET6 && type == ICMPV6_ECHO_REQUEST && code == 0) ||
+	       (family == AF_INET6 && type == ICMPV6_EXT_ECHO_REQUEST && code == 0);
 }
 
 /*
-- 
2.29.2

[PATCH v3 net-next 2/3] icmp: define PROBE message types

[Andreas Roeseler]

The types of ICMP Extended Echo Request and ICMP Extended Echo Reply are
defined in sections 2 and 3 of RFC8335.

Signed-off-by: Andreas Roeseler <andreas.a.roeseler@gmail.com>
---
Changes since v1:
 - Switch to correct base tree

Changes since v2:
 - Switch to net-next tree 67c70b5eb2bf7d0496fcb62d308dc3096bc11553
---
 include/uapi/linux/icmp.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/include/uapi/linux/icmp.h b/include/uapi/linux/icmp.h
index fb169a50895e..1a84450f667f 100644
--- a/include/uapi/linux/icmp.h
+++ b/include/uapi/linux/icmp.h
@@ -66,6 +66,9 @@
 #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
 
 struct icmphdr {
   __u8		type;
-- 
2.29.2

[PATCH v3 net-next 3/3] ICMPv6: define PROBE message types

[Andreas Roeseler]

The types of ICMPV6 Extended Echo Request and ICMPV6 Extended Echo Reply
are defined in sections 2 and 3 of RFC8335.

Signed-off-by: Andreas Roeseler <andreas.a.roeseler@gmail.com>
---
Changes since v1:
 - Switch to correct base tree

Changes since v2:
 - Switch to net-next tree 67c70b5eb2bf7d0496fcb62d308dc3096bc11553
---
 include/uapi/linux/icmpv6.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/include/uapi/linux/icmpv6.h b/include/uapi/linux/icmpv6.h
index 0564fd7ccde4..54dbafdedca1 100644
--- a/include/uapi/linux/icmpv6.h
+++ b/include/uapi/linux/icmpv6.h
@@ -140,6 +140,12 @@ 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
  */
-- 
2.29.2

Re: [PATCH v3 net-next 1/3] net: add support for sending RFC8335 PROBE

[Jakub Kicinski]

On Sat, 14 Nov 2020 12:56:11 -0800 Andreas Roeseler wrote:
> Modifying the ping_supported function to support probe message types
> allows the user to send probe requests through the existing framework
> for sending ping requests.
> 
> Signed-off-by: Andreas Roeseler <andreas.a.roeseler@gmail.com>

You need to reorder the patches so that defines are added first.

Otherwise if someone lands on this patch during bisection the kernel
will not build:

../net/ipv4/ping.c: In function ‘ping_supported’:
../net/ipv4/ping.c:456:39: error: ‘ICMP_EXT_ECHO’ undeclared (first use in this function); did you mean ‘ICMP_ECHO’?
  456 |         (family == AF_INET && type == ICMP_EXT_ECHO && code == 0) ||
      |                                       ^~~~~~~~~~~~~
      |                                       ICMP_ECHO
../net/ipv4/ping.c:456:39: note: each undeclared identifier is reported only once for each function it appears in
../net/ipv4/ping.c:458:40: error: ‘ICMPV6_EXT_ECHO_REQUEST’ undeclared (first use in this function); did you mean ‘ICMPV6_ECHO_REQUEST’?
  458 |         (family == AF_INET6 && type == ICMPV6_EXT_ECHO_REQUEST && code == 0);
      |                                        ^~~~~~~~~~~~~~~~~~~~~~~
      |                                        ICMPV6_ECHO_REQUEST
../net/ipv4/ping.c:459:1: error: control reaches end of non-void function [-Werror=return-type]
  459 | }
      | ^
cc1: some warnings being treated as errors
make[3]: *** [net/ipv4/ping.o] Error 1
make[2]: *** [net/ipv4] Error 2
make[2]: *** Waiting for unfinished jobs....
make[1]: *** [net] Error 2
make[1]: *** Waiting for unfinished jobs....
make: *** [__sub-make] Error 2