From b65a9a258a0fc3c19a64a8426b28f7bcbe438cf5 Mon Sep 17 00:00:00 2001
From: Phil Sutter <phil@nwl.cc>
Date: Fri, 5 Apr 2019 13:21:19 +0200
Subject: [PATCH] xshared: Merge and share parse_chain()

Have a common routine to perform chain name checks, combining all
variants' requirements.

Signed-off-by: Phil Sutter <phil@nwl.cc>
(cherry picked from commit 1189d830ea4fd269da87761d400ebabca02e1ef3)

Conflicts:
	iptables/ip6tables.c
	iptables/xshared.c
-> Context changes due to missing commit 9dc50b5b8e441
   ("xshared: Merge invflags handling code")
---
 iptables/ip6tables.c | 26 --------------------------
 iptables/iptables.c  | 25 -------------------------
 iptables/xshared.c   | 24 ++++++++++++++++++++++++
 iptables/xshared.h   |  1 +
 iptables/xtables.c   |  9 +--------
 5 files changed, 26 insertions(+), 59 deletions(-)

diff --git a/iptables/ip6tables.c b/iptables/ip6tables.c
index c95355b091568..f53d0a8d0f169 100644
--- a/iptables/ip6tables.c
+++ b/iptables/ip6tables.c
@@ -248,32 +248,6 @@ static int is_exthdr(uint16_t proto)
 		proto == IPPROTO_DSTOPTS);
 }
 
-static void
-parse_chain(const char *chainname)
-{
-	const char *ptr;
-
-	if (strlen(chainname) >= XT_EXTENSION_MAXNAMELEN)
-		xtables_error(PARAMETER_PROBLEM,
-			   "chain name `%s' too long (must be under %u chars)",
-			   chainname, XT_EXTENSION_MAXNAMELEN);
-
-	if (*chainname == '-' || *chainname == '!')
-		xtables_error(PARAMETER_PROBLEM,
-			   "chain name not allowed to start "
-			   "with `%c'\n", *chainname);
-
-	if (xtables_find_target(chainname, XTF_TRY_LOAD))
-		xtables_error(PARAMETER_PROBLEM,
-			   "chain name may not clash "
-			   "with target name\n");
-
-	for (ptr = chainname; *ptr; ptr++)
-		if (isspace(*ptr))
-			xtables_error(PARAMETER_PROBLEM,
-				   "Invalid chain name `%s'", chainname);
-}
-
 static void
 set_option(unsigned int *options, unsigned int option, uint8_t *invflg,
 	   int invert)
diff --git a/iptables/iptables.c b/iptables/iptables.c
index 7d6183116d265..18cc4f7690a24 100644
--- a/iptables/iptables.c
+++ b/iptables/iptables.c
@@ -239,31 +239,6 @@ iptables_exit_error(enum xtables_exittype status, const char *msg, ...)
 
 /* Christophe Burki wants `-p 6' to imply `-m tcp'.  */
 
-static void
-parse_chain(const char *chainname)
-{
-	const char *ptr;
-
-	if (strlen(chainname) >= XT_EXTENSION_MAXNAMELEN)
-		xtables_error(PARAMETER_PROBLEM,
-			   "chain name `%s' too long (must be under %u chars)",
-			   chainname, XT_EXTENSION_MAXNAMELEN);
-
-	if (*chainname == '-' || *chainname == '!')
-		xtables_error(PARAMETER_PROBLEM,
-			   "chain name not allowed to start "
-			   "with `%c'\n", *chainname);
-
-	if (xtables_find_target(chainname, XTF_TRY_LOAD))
-		xtables_error(PARAMETER_PROBLEM,
-			   "chain name may not clash "
-			   "with target name\n");
-
-	for (ptr = chainname; *ptr; ptr++)
-		if (isspace(*ptr))
-			xtables_error(PARAMETER_PROBLEM,
-				   "Invalid chain name `%s'", chainname);
-}
 
 static void
 set_option(unsigned int *options, unsigned int option, uint8_t *invflg,
diff --git a/iptables/xshared.c b/iptables/xshared.c
index 68aea42146c36..d71724a2591dc 100644
--- a/iptables/xshared.c
+++ b/iptables/xshared.c
@@ -853,3 +853,27 @@ char opt2char(int option)
 
 	return *ptr;
 }
+
+void parse_chain(const char *chainname)
+{
+	const char *ptr;
+
+	if (strlen(chainname) >= XT_EXTENSION_MAXNAMELEN)
+		xtables_error(PARAMETER_PROBLEM,
+			      "chain name `%s' too long (must be under %u chars)",
+			      chainname, XT_EXTENSION_MAXNAMELEN);
+
+	if (*chainname == '-' || *chainname == '!')
+		xtables_error(PARAMETER_PROBLEM,
+			      "chain name not allowed to start with `%c'\n",
+			      *chainname);
+
+	if (xtables_find_target(chainname, XTF_TRY_LOAD))
+		xtables_error(PARAMETER_PROBLEM,
+			      "chain name may not clash with target name\n");
+
+	for (ptr = chainname; *ptr; ptr++)
+		if (isspace(*ptr))
+			xtables_error(PARAMETER_PROBLEM,
+				      "Invalid chain name `%s'", chainname);
+}
diff --git a/iptables/xshared.h b/iptables/xshared.h
index 1e86aba8b2375..4f52117d5228d 100644
--- a/iptables/xshared.h
+++ b/iptables/xshared.h
@@ -223,6 +223,7 @@ char cmd2char(int option);
 void add_command(unsigned int *cmd, const int newcmd,
 		 const int othercmds, int invert);
 int parse_rulenumber(const char *rule);
+void parse_chain(const char *chainname);
 
 void generic_opt_check(int command, int options);
 char opt2char(int option);
diff --git a/iptables/xtables.c b/iptables/xtables.c
index 9779bd83d53b3..54f887f80497e 100644
--- a/iptables/xtables.c
+++ b/iptables/xtables.c
@@ -587,14 +587,7 @@ void do_parse(struct nft_handle *h, int argc, char *argv[],
 			break;
 
 		case 'N':
-			if (optarg && (*optarg == '-' || *optarg == '!'))
-				xtables_error(PARAMETER_PROBLEM,
-					   "chain name not allowed to start "
-					   "with `%c'\n", *optarg);
-			if (xtables_find_target(optarg, XTF_TRY_LOAD))
-				xtables_error(PARAMETER_PROBLEM,
-					   "chain name may not clash "
-					   "with target name\n");
+			parse_chain(optarg);
 			add_command(&p->command, CMD_NEW_CHAIN, CMD_NONE,
 				    cs->invert);
 			p->chain = optarg;
-- 
2.34.1