src: revisit tcp options support

Rework syntax, add tokens so we can extend the grammar more easily.
This has triggered several syntax changes with regards to the original
patch, specifically:

	tcp option sack0 left 1

There is no space between sack and the block number anymore, no more
offset field, now they are a single field. Just like we do with rt, rt0
and rt2. This simplifies our grammar and that is good since it makes our
life easier when extending it later on to accomodate new features.

I have also renamed sack_permitted to sack-permitted. I couldn't find
any option using underscore so far, so let's keep it consistent with
what we have.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 48 insertions, 33 deletions

diff --git a/src/parser_bison.y b/src/parser_bison.y
index 36d46050..15931e96 100644
--- a/src/parser_bison.y
+++ b/src/parser_bison.y
@@ -309,6 +309,23 @@ static void location_update(struct location *loc, struct location *rhs, int n)
 %token WINDOW			"window"
 %token URGPTR			"urgptr"
 %token OPTION			"option"
+%token ECHO			"echo"
+%token EOL			"eol"
+%token MAXSEG			"maxseg"
+%token NOOP			"noop"
+%token SACK			"sack"
+%token SACK0			"sack0"
+%token SACK1			"sack1"
+%token SACK2			"sack2"
+%token SACK3			"sack3"
+%token SACK_PERMITTED		"sack-permitted"
+%token TIMESTAMP		"timestamp"
+%token KIND			"kind"
+%token COUNT			"count"
+%token LEFT			"left"
+%token RIGHT			"right"
+%token TSVAL			"tsval"
+%token TSECR			"tsecr"
 
 %token DCCP			"dccp"
 
@@ -430,8 +447,8 @@ static void location_update(struct location *loc, struct location *rhs, int n)
 
 %token NOTRACK			"notrack"
 
-%type <string>			identifier type_identifier string comment_spec tcp_option_name tcp_option_field
-%destructor { xfree($$); }	identifier type_identifier string comment_spec tcp_option_name tcp_option_field
+%type <string>			identifier type_identifier string comment_spec
+%destructor { xfree($$); }	identifier type_identifier string comment_spec
 
 %type <val>			time_spec quota_used
 
@@ -602,9 +619,6 @@ static void location_update(struct location *loc, struct location *rhs, int n)
 %destructor { expr_free($$); }	mh_hdr_expr
 %type <val>			mh_hdr_field
 
-%type <expr>			tcp_hdr_optexpr
-%destructor { expr_free($$); }	tcp_hdr_optexpr
-
 %type <expr>			meta_expr
 %destructor { expr_free($$); }	meta_expr
 %type <val>			meta_key	meta_key_qualified	meta_key_unqualified	numgen_type
@@ -634,6 +648,7 @@ static void location_update(struct location *loc, struct location *rhs, int n)
 %type <expr>			tcp_hdr_expr
 %destructor { expr_free($$); }	tcp_hdr_expr
 %type <val>			tcp_hdr_field
+%type <val>			tcp_hdr_option_type tcp_hdr_option_field
 
 %%
 
@@ -3211,6 +3226,10 @@ tcp_hdr_expr		:	TCP	tcp_hdr_field
 			{
 				$$ = payload_expr_alloc(&@$, &proto_tcp, $2);
 			}
+			|	TCP	OPTION	tcp_hdr_option_type tcp_hdr_option_field
+			{
+				$$ = tcpopt_expr_alloc(&@$, $3, $4);
+			}
 			;
 
 tcp_hdr_field		:	SPORT		{ $$ = TCPHDR_SPORT; }
@@ -3225,6 +3244,30 @@ tcp_hdr_field		:	SPORT		{ $$ = TCPHDR_SPORT; }
 			|	URGPTR		{ $$ = TCPHDR_URGPTR; }
 			;
 
+tcp_hdr_option_type	:	EOL		{ $$ = TCPOPTHDR_EOL; }
+			|	NOOP		{ $$ = TCPOPTHDR_NOOP; }
+			|	MAXSEG		{ $$ = TCPOPTHDR_MAXSEG; }
+			|	WINDOW		{ $$ = TCPOPTHDR_WINDOW; }
+			|	SACK_PERMITTED	{ $$ = TCPOPTHDR_SACK_PERMITTED; }
+			|	SACK		{ $$ = TCPOPTHDR_SACK0; }
+			|	SACK0		{ $$ = TCPOPTHDR_SACK0; }
+			|	SACK1		{ $$ = TCPOPTHDR_SACK1; }
+			|	SACK2		{ $$ = TCPOPTHDR_SACK2; }
+			|	SACK3		{ $$ = TCPOPTHDR_SACK3; }
+			|	ECHO		{ $$ = TCPOPTHDR_ECHO; }
+			|	TIMESTAMP	{ $$ = TCPOPTHDR_TIMESTAMP; }
+			;
+
+tcp_hdr_option_field	:	KIND		{ $$ = TCPOPTHDR_FIELD_KIND; }
+			|	LENGTH		{ $$ = TCPOPTHDR_FIELD_LENGTH; }
+			|	SIZE		{ $$ = TCPOPTHDR_FIELD_SIZE; }
+			|	COUNT		{ $$ = TCPOPTHDR_FIELD_COUNT; }
+			|	LEFT		{ $$ = TCPOPTHDR_FIELD_LEFT; }
+			|	RIGHT		{ $$ = TCPOPTHDR_FIELD_RIGHT; }
+			|	TSVAL		{ $$ = TCPOPTHDR_FIELD_TSVAL; }
+			|	TSECR		{ $$ = TCPOPTHDR_FIELD_TSECR; }
+			;
+
 dccp_hdr_expr		:	DCCP	dccp_hdr_field
 			{
 				$$ = payload_expr_alloc(&@$, &proto_dccp, $2);
@@ -3255,7 +3298,6 @@ exthdr_expr		:	hbh_hdr_expr
 			|	frag_hdr_expr
 			|	dst_hdr_expr
 			|	mh_hdr_expr
-			|	tcp_hdr_optexpr
 			;
 
 hbh_hdr_expr		:	HBH	hbh_hdr_field
@@ -3338,31 +3380,4 @@ mh_hdr_field		:	NEXTHDR		{ $$ = MHHDR_NEXTHDR; }
 			|	CHECKSUM	{ $$ = MHHDR_CHECKSUM; }
 			;
 
-tcp_option_name		:	STRING		{ $$ = $1; }
-			|	WINDOW		{ $$ = xstrdup("window"); }
-			;
-
-tcp_option_field	:	STRING		{ $$ = $1; }
-			|	LENGTH		{ $$ = xstrdup("length"); }
-			|	SIZE		{ $$ = xstrdup("size"); }
-			;
-
-tcp_hdr_optexpr		:	TCP	OPTION	tcp_option_name		tcp_option_field
-			{
-				$$ = tcpopt_expr_alloc(&@$, $3, 0, $4);
-			}
-			|	TCP	OPTION	STRING	NUM	tcp_option_field
-			{
-				if (strcmp($3, "sack")) {
-					erec_queue(error(&@2, "tcp: number (%d) can only be used with sack option", $4), state->msgs);
-					YYERROR;
-				}
-
-				if ($4 > 3) {
-					erec_queue(error(&@2, "tcp: option block (%d) too large (0-3)", $4), state->msgs);
-					YYERROR;
-				}
-				$$ = tcpopt_expr_alloc(&@$, $3, $4, $5);
-			}
-			;
 %%