Subject: [PATCH iproute2-next 4/4] ip: Add ability to flush a rule based upon protocol

From: Donald Sharp <[email-masked]>
Date: Tue, 20 Feb 2018 20:53:48 -0500

Add code to allow the `ip rule flush protocol XXX`
command to be accepted and properly handled.

Additionally modify the documentation to be correct
with these changes.

Signed-off-by: Donald Sharp <[email-masked]>
---
 ip/iprule.c        | 25 ++++++++++++++++++-------
 man/man8/ip-rule.8 | 18 +++++++++++++++++-
 2 files changed, 35 insertions(+), 8 deletions(-)

diff --git a/ip/iprule.c b/ip/iprule.c
index fd242fee..b69413dd 100644
--- a/ip/iprule.c
+++ b/ip/iprule.c
@@ -47,6 +47,7 @@ static void usage(void)
 		"            [ iif STRING ] [ oif STRING ] [ pref NUMBER ] [ l3mdev ]\n"
 		"            [ uidrange NUMBER-NUMBER ]\n"
 		"ACTION := [ table TABLE_ID ]\n"
+		"          [ protocol RPROTO ]\n"
 		"          [ nat ADDRESS ]\n"
 		"          [ realms [SRCREALM/]DSTREALM ]\n"
 		"          [ goto NUMBER ]\n"
@@ -71,6 +72,8 @@ static struct
 	struct fib_rule_uid_range range;
 	inet_prefix src;
 	inet_prefix dst;
+	int protocol;
+	int protocolmask;
 } filter;
 
 static bool filter_nlmsg(struct nlmsghdr *n, struct rtattr **tb, int host_len)
@@ -398,6 +401,9 @@ static int flush_rule(const struct sockaddr_nl *who, struct nlmsghdr *n,
 
 	parse_rtattr(tb, FRA_MAX, RTM_RTA(frh), len);
 
+	if ((filter.protocol^frh->proto)&filter.protocolmask)
+		return 0;
+
 	if (tb[FRA_PRIORITY]) {
 		n->nlmsg_type = RTM_DELRULE;
 		n->nlmsg_flags = NLM_F_REQUEST;
@@ -422,12 +428,6 @@ static int iprule_list_flush_or_save(int argc, char **argv, int action)
 	if (af == AF_UNSPEC)
 		af = AF_INET;
 
-	if (action != IPRULE_LIST && argc > 0) {
-		fprintf(stderr, "\"ip rule %s\" does not take any arguments.\n",
-				action == IPRULE_SAVE ? "save" : "flush");
-		return -1;
-	}
-
 	switch (action) {
 	case IPRULE_SAVE:
 		if (save_rule_prep())
@@ -515,7 +515,18 @@ static int iprule_list_flush_or_save(int argc, char **argv, int action)
 			NEXT_ARG();
 			if (get_prefix(&filter.src, *argv, af))
 				invarg("from value is invalid\n", *argv);
-		} else {
+		} else if (matches(*argv, "protocol") == 0) {
+			__u32 prot;
+			NEXT_ARG();
+			filter.protocolmask = -1;
+			if (rtnl_rtprot_a2n(&prot, *argv)) {
+				if (strcmp(*argv, "all") != 0)
+					invarg("invalid \"protocol\"\n", *argv);
+				prot = 0;
+				filter.protocolmask = 0;
+			}
+			filter.protocol = prot;
+		} else{
 			if (matches(*argv, "dst") == 0 ||
 			    matches(*argv, "to") == 0) {
 				NEXT_ARG();
diff --git a/man/man8/ip-rule.8 b/man/man8/ip-rule.8
index a5c47981..98b2573d 100644
--- a/man/man8/ip-rule.8
+++ b/man/man8/ip-rule.8
@@ -50,6 +50,8 @@ ip-rule \- routing policy database management
 .IR ACTION " := [ "
 .B  table
 .IR TABLE_ID " ] [ "
+.B  protocol
+.IR RPROTO " ] [ "
 .B  nat
 .IR ADDRESS " ] [ "
 .B realms
@@ -240,6 +242,10 @@ The options preference and order are synonyms with priority.
 the routing table identifier to lookup if the rule selector matches.
 It is also possible to use lookup instead of table.
 
+.TP
+.BI protocol " RPROTO"
+the protocol who installed the rule in question.
+
 .TP
 .BI suppress_prefixlength " NUMBER"
 reject routing decisions that have a prefix length of NUMBER or less.
@@ -275,7 +281,11 @@ updates, it flushes the routing cache with
 .RE
 .TP
 .B ip rule flush - also dumps all the deleted rules.
-This command has no arguments.
+.RS
+.TP
+.BI protocol " RPROTO"
+Select the originating protocol.
+.RE
 .TP
 .B ip rule show - list rules
 This command has no arguments.
@@ -283,6 +293,12 @@ The options list or lst are synonyms with show.
 
 .TP
 .B ip rule save
+.RS
+.TP
+.BI protocl " RPROTO"
+Select the originating protocol.
+.RE
+.TP
 save rules table information to stdout
 .RS
 This command behaves like
-- 
2.14.3