trafgen: proto: Add IPv6 header generation

Support for generating simple IPv6 headers using the 'ip6()/ipv6()'
trafgen generation function.

Fields supported:

  ver|version      Version (default: 6)
  tc|tclass        Traffic class (default: 0)
  fl|flow          Flow Label (default: 0)
  len|length       Payload length (calculated by default)
  nh|nexthdr       Type of next header (default: 0)
  hl|hoplimit|ttl  Hop Limit, TTL (default: 0)
  sa|saddr         Source IPv6 address (default: device address)
  da|daddr         Destination IPv6 address (default: 0:0:0:0:0:0:0:0)

Examples:

  { eth(), ipv6(daddr=1:2:3:4:5:6:7:8) }
  { ipv6(tc=2, hl=3, daddr=::1) }
  { eth(), ipv6(nh=58, sa=2001:db8::, da=::1), 128, 0, 0x52, 0x03, 0, 0, 0, 0 }

If not explicitely specified, the lower header is initialized as Ethernet.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>

8 files changed, 254 insertions, 40 deletions

diff --git a/trafgen.8 b/trafgen.8
index 300277b..c81fecb 100644
--- a/trafgen.8
+++ b/trafgen.8
@@ -424,7 +424,7 @@ destination MAC address is set to the broadcast address (ff:ff:ff:ff:ff:ff).
 - Explicit Congestion Notification (ECN) field (default: 0)
 .sp
 .B len|length
-- Total length of header and data (calculated by default)
+- Total length of header and payload (calculated by default)
 .sp
 .B id
 - IPv4 datagram identification (default: 0)
@@ -461,6 +461,43 @@ By default, if the lower level header is Ethernet, its EtherType field is set to
 0x0800 (IPv4). If the lower level header is IPv4, its protocol field is set to
 0x4 (IP-in-IP).
 
+.I IPv6
+:
+.B ip6|ipv6(ver=<number>, class=<number>, flow=<number> len=<number>,
+.B nexthdr=<number>, hoplimit=<number>,
+.in +16
+.B da=<ip6_addr>, sa=<ip6_addr>)
+.in -16
+.sp
+.in +4
+.B ver|version
+- Version field (default: 6)
+.sp
+.B tc|tclass
+- Traffic class (default: 0)
+.sp
+.B fl|flow
+- Flow label (default: 0)
+.sp
+.B len|length
+- Payload length (calculated by default)
+.sp
+.B nh|nexthdr
+- Type of next header, i.e. transport layer protocol number (default: 0)
+.sp
+.B hl|hoplimit|ttl
+- Hop limit, i.e. time to live (default: 0)
+.sp
+.B sa|saddr
+- Source IPv6 address (default: device IPv6 address)
+.sp
+.B da|daddr
+- Destination IPv6 address (default: 0:0:0:0:0:0:0:0)
+.in -4
+.sp
+By default, if the lower level header is Ethernet, its EtherType field is set to
+0x86DD (IPv6).
+
 .I UDP
 :
 .B udp(sp=<number>, dp=<number>, len=<number>, csum=<number>)
diff --git a/trafgen_l3.c b/trafgen_l3.c
index 88766ea..94c0755 100644
--- a/trafgen_l3.c
+++ b/trafgen_l3.c
@@ -90,7 +90,65 @@ static struct proto_hdr ipv4_hdr = {
 	.set_next_proto = ipv4_set_next_proto,
 };
 
+static struct proto_field ipv6_fields[] = {
+	{ .id = IP6_VER,       .len = 4,  .offset = 0, .shift = 28, .mask = 0xf0000000 },
+	{ .id = IP6_CLASS,     .len = 4,  .offset = 0, .shift = 20, .mask = 0x0ff00000 },
+	{ .id = IP6_FLOW_LBL,  .len = 4,  .offset = 0, .shift = 0,  .mask = 0x000fffff },
+	{ .id = IP6_LEN,       .len = 2,  .offset = 4 },
+	{ .id = IP6_NEXT_HDR,  .len = 1,  .offset = 6 },
+	{ .id = IP6_HOP_LIMIT, .len = 1,  .offset = 7 },
+	{ .id = IP6_SADDR,     .len = 16, .offset = 8 },
+	{ .id = IP6_DADDR,     .len = 16, .offset = 24 },
+};
+
+static void ipv6_header_init(struct proto_hdr *hdr)
+{
+	proto_lower_default_add(hdr, PROTO_ETH);
+
+	proto_header_fields_add(hdr, ipv6_fields, array_size(ipv6_fields));
+
+	proto_field_set_default_be32(hdr, IP6_VER, 6);
+	proto_field_set_default_dev_ipv6(hdr, IP6_SADDR);
+}
+
+#define IPV6_HDR_LEN 40
+
+static void ipv6_packet_finish(struct proto_hdr *hdr)
+{
+	struct packet *pkt = current_packet();
+	uint16_t total_len = pkt->len - hdr->pkt_offset - IPV6_HDR_LEN;
+
+	proto_field_set_default_be16(hdr, IP6_LEN, total_len);
+}
+
+static void ipv6_set_next_proto(struct proto_hdr *hdr, enum proto_id pid)
+{
+	uint8_t ip_proto;
+
+	switch(pid) {
+	case PROTO_UDP:
+		ip_proto = IPPROTO_UDP;
+		break;
+	case PROTO_TCP:
+		ip_proto = IPPROTO_TCP;
+		break;
+	default:
+		bug();
+	}
+
+	proto_field_set_default_u8(hdr, IP6_NEXT_HDR, ip_proto);
+}
+
+static struct proto_hdr ipv6_hdr = {
+	.id             = PROTO_IP6,
+	.layer          = PROTO_L3,
+	.header_init    = ipv6_header_init,
+	.packet_finish  = ipv6_packet_finish,
+	.set_next_proto = ipv6_set_next_proto,
+};
+
 void protos_l3_init(void)
 {
 	proto_header_register(&ipv4_hdr);
+	proto_header_register(&ipv6_hdr);
 }
diff --git a/trafgen_l3.h b/trafgen_l3.h
index 9427378..a1b1523 100644
--- a/trafgen_l3.h
+++ b/trafgen_l3.h
@@ -20,6 +20,17 @@ enum ip4_field {
 	IP4_MF,
 };
 
+enum ip6_field {
+	IP6_VER,
+	IP6_CLASS,
+	IP6_FLOW_LBL,
+	IP6_LEN,
+	IP6_NEXT_HDR,
+	IP6_HOP_LIMIT,
+	IP6_SADDR,
+	IP6_DADDR,
+};
+
 extern void protos_l3_init(void);
 
 #endif /* TRAFGEN_L2_H */
diff --git a/trafgen_l4.c b/trafgen_l4.c
index 64aada4..a5981c4 100644
--- a/trafgen_l4.c
+++ b/trafgen_l4.c
@@ -15,30 +15,10 @@
 #include "trafgen_proto.h"
 
 static struct proto_field udp_fields[] = {
-	{ .id = UDP_SPORT,	.len = 2,	.offset = 0 },
-	{ .id = UDP_DPORT,	.len = 2,	.offset = 2 },
-	{ .id = UDP_LEN,	.len = 2,	.offset = 4 },
-	{ .id = UDP_CSUM,	.len = 2,	.offset = 6 },
-};
-
-static struct proto_field tcp_fields[] = {
-	{ .id = TCP_SPORT,   .len = 2, .offset = 0 },
-	{ .id = TCP_DPORT,   .len = 2, .offset = 2 },
-	{ .id = TCP_SEQ,     .len = 4, .offset = 4 },
-	{ .id = TCP_ACK_SEQ, .len = 4, .offset = 8 },
-	{ .id = TCP_DOFF,    .len = 2, .offset = 12, .shift = 12, .mask = 0xf000 },
-	/* reserved (4 bits) */
-	{ .id = TCP_CWR,     .len = 2, .offset = 12, .shift = 7, .mask = 0x0080 },
-	{ .id = TCP_ECE,     .len = 2, .offset = 12, .shift = 6, .mask = 0x0040 },
-	{ .id = TCP_URG,     .len = 2, .offset = 12, .shift = 5, .mask = 0x0020 },
-	{ .id = TCP_ACK,     .len = 2, .offset = 12, .shift = 4, .mask = 0x0010 },
-	{ .id = TCP_PSH,     .len = 2, .offset = 12, .shift = 3, .mask = 0x0008 },
-	{ .id = TCP_RST,     .len = 2, .offset = 12, .shift = 2, .mask = 0x0004 },
-	{ .id = TCP_SYN,     .len = 2, .offset = 12, .shift = 1, .mask = 0x0002 },
-	{ .id = TCP_FIN,     .len = 2, .offset = 12, .shift = 0, .mask = 0x0001 },
-	{ .id = TCP_WINDOW,  .len = 2, .offset = 14 },
-	{ .id = TCP_CSUM,    .len = 2, .offset = 16 },
-	{ .id = TCP_URG_PTR, .len = 2, .offset = 18 },
+	{ .id = UDP_SPORT, .len = 2, .offset = 0 },
+	{ .id = UDP_DPORT, .len = 2, .offset = 2 },
+	{ .id = UDP_LEN,   .len = 2, .offset = 4 },
+	{ .id = UDP_CSUM,  .len = 2, .offset = 6 },
 };
 
 static void udp_header_init(struct proto_hdr *hdr)
@@ -61,12 +41,24 @@ static void udp_packet_finish(struct proto_hdr *hdr)
 	if (proto_field_is_set(hdr, UDP_CSUM))
 		return;
 
-	if (!lower || lower->id != PROTO_IP4)
+	if (!lower)
 		return;
 
 	total_len = proto_field_get_u16(hdr, UDP_LEN);
-	csum = p4_csum((void *) proto_header_ptr(lower), proto_header_ptr(hdr),
-			total_len, IPPROTO_UDP);
+
+	switch (lower->id) {
+	case PROTO_IP4:
+		csum = p4_csum((void *) proto_header_ptr(lower), proto_header_ptr(hdr),
+				total_len, IPPROTO_UDP);
+		break;
+	case PROTO_IP6:
+		csum = p6_csum((void *) proto_header_ptr(lower), proto_header_ptr(hdr),
+				total_len, IPPROTO_UDP);
+		break;
+	default:
+		csum = 0;
+		break;
+	}
 
 	proto_field_set_be16(hdr, UDP_CSUM, bswap_16(csum));
 }
@@ -78,6 +70,26 @@ static struct proto_hdr udp_hdr = {
 	.packet_finish  = udp_packet_finish,
 };
 
+static struct proto_field tcp_fields[] = {
+	{ .id = TCP_SPORT,   .len = 2, .offset = 0 },
+	{ .id = TCP_DPORT,   .len = 2, .offset = 2 },
+	{ .id = TCP_SEQ,     .len = 4, .offset = 4 },
+	{ .id = TCP_ACK_SEQ, .len = 4, .offset = 8 },
+	{ .id = TCP_DOFF,    .len = 2, .offset = 12, .shift = 12, .mask = 0xf000 },
+	/* reserved (4 bits) */
+	{ .id = TCP_CWR,     .len = 2, .offset = 12, .shift = 7, .mask = 0x0080 },
+	{ .id = TCP_ECE,     .len = 2, .offset = 12, .shift = 6, .mask = 0x0040 },
+	{ .id = TCP_URG,     .len = 2, .offset = 12, .shift = 5, .mask = 0x0020 },
+	{ .id = TCP_ACK,     .len = 2, .offset = 12, .shift = 4, .mask = 0x0010 },
+	{ .id = TCP_PSH,     .len = 2, .offset = 12, .shift = 3, .mask = 0x0008 },
+	{ .id = TCP_RST,     .len = 2, .offset = 12, .shift = 2, .mask = 0x0004 },
+	{ .id = TCP_SYN,     .len = 2, .offset = 12, .shift = 1, .mask = 0x0002 },
+	{ .id = TCP_FIN,     .len = 2, .offset = 12, .shift = 0, .mask = 0x0001 },
+	{ .id = TCP_WINDOW,  .len = 2, .offset = 14 },
+	{ .id = TCP_CSUM,    .len = 2, .offset = 16 },
+	{ .id = TCP_URG_PTR, .len = 2, .offset = 18 },
+};
+
 static void tcp_header_init(struct proto_hdr *hdr)
 {
 	proto_lower_default_add(hdr, PROTO_IP4);
@@ -97,12 +109,24 @@ static void tcp_packet_finish(struct proto_hdr *hdr)
 	if (proto_field_is_set(hdr, TCP_CSUM))
 		return;
 
-	if (!lower || lower->id != PROTO_IP4)
+	if (!lower)
 		return;
 
 	total_len = pkt->len - hdr->pkt_offset;
-	csum = p4_csum((void *) proto_header_ptr(lower), proto_header_ptr(hdr),
-			total_len, IPPROTO_TCP);
+
+	switch (lower->id) {
+	case PROTO_IP4:
+		csum = p4_csum((void *) proto_header_ptr(lower), proto_header_ptr(hdr),
+				total_len, IPPROTO_TCP);
+		break;
+	case PROTO_IP6:
+		csum = p6_csum((void *) proto_header_ptr(lower), proto_header_ptr(hdr),
+				total_len, IPPROTO_TCP);
+		break;
+	default:
+		csum = 0;
+		break;
+	}
 
 	proto_field_set_be16(hdr, TCP_CSUM, bswap_16(csum));
 }
diff --git a/trafgen_lexer.l b/trafgen_lexer.l
index 3c624f8..a093ac1 100644
--- a/trafgen_lexer.l
+++ b/trafgen_lexer.l
@@ -77,9 +77,13 @@ number_bin	([0]?[b][0-1]+)
 number_dec	(([0])|([1-9][0-9]*))
 number_ascii	([a-zA-Z])
 
-mac_hex		([a-fA-F0-9]+)
-mac		({mac_hex}:{mac_hex}:{mac_hex}:{mac_hex}:{mac_hex}:{mac_hex})
+a_hex		([a-fA-F0-9]+)
+mac		({a_hex}:{a_hex}:{a_hex}:{a_hex}:{a_hex}:{a_hex})
 ip4_addr	([0-9]+\.[0-9]+\.[0-9]+\.[0-9]+)
+	/* We're very permissive about IPv6 addresses the grammar accepts, as
+	 * they can come in various different formats. In any case,
+	 * inet_pton(AF_INET6, ...) will reject the invalid ones later on. */
+ip6_addr	(({a_hex}?:)?({a_hex}?:)?({a_hex}?:)?({a_hex}?:)?({a_hex}?:)?({a_hex}?:)?({a_hex}?:)?({a_hex})?)
 
 %%
 
@@ -106,6 +110,7 @@ ip4_addr	([0-9]+\.[0-9]+\.[0-9]+\.[0-9]+)
 "const64"|"c64"	{ return K_CONST64; }
 
 "prot"[o]?	{ return K_PROT; }
+"tc"|"tclass"	{ return K_TC; }
 
 	/* Ethernet */
 "daddr"|"da"	{ return K_DADDR; }
@@ -123,7 +128,6 @@ ip4_addr	([0-9]+\.[0-9]+\.[0-9]+\.[0-9]+)
 	/* MPLS (Multi Protocol Label Switching) */
 "lbl"|"label"	{ return K_LABEL; }
 "last"		{ return K_LAST; }
-"tc"|"tclass"	{ return K_TC; }
 "exp"		{ return K_EXP; }
 
 	/* ARP */
@@ -152,6 +156,11 @@ ip4_addr	([0-9]+\.[0-9]+\.[0-9]+\.[0-9]+)
 "df"		{ return K_DF; }
 "mf"		{ return K_MF; }
 
+	/* IPv6 */
+"fl"|"flow"	{ return K_FLOW; }
+"nh"|"nexthdr"	{ return K_NEXT_HDR; }
+"hl"|"hoplimit"	{ return K_HOP_LIMIT; }
+
 	/* UDP */
 "sp"|"sport"	{ return K_SPORT; }
 "dp"|"dport"	{ return K_DPORT; }
@@ -176,6 +185,7 @@ ip4_addr	([0-9]+\.[0-9]+\.[0-9]+\.[0-9]+)
 "mpls"		{ return K_MPLS; }
 "arp"		{ return K_ARP; }
 "ip4"|"ipv4"	{ return K_IP4; }
+"ip6"|"ipv6"	{ return K_IP6; }
 "udp"		{ return K_UDP; }
 "tcp"		{ return K_TCP; }
 
@@ -235,6 +245,10 @@ ip4_addr	([0-9]+\.[0-9]+\.[0-9]+\.[0-9]+)
 			panic("Failed to parse IPv4 address %s\n", yytext);
 		  return ip4_addr; };
 
+{ip6_addr}	{ if (inet_pton(AF_INET6, yytext, &yylval.ip6_addr) != 1)
+			panic("Failed to parse IPv6 address %s\n", yytext);
+		  return ip6_addr; };
+
 "'\\x"[a-fA-F0-9]{2}"'" { yylval.number = strtol(yytext + 3, NULL, 16);
 		  return number; }
 
diff --git a/trafgen_parser.y b/trafgen_parser.y
index 0b1c0fb..d6c9e70 100644
--- a/trafgen_parser.y
+++ b/trafgen_parser.y
@@ -342,6 +342,7 @@ static void proto_add(enum proto_id pid)
 
 %union {
 	struct in_addr ip4_addr;
+	struct in6_addr ip6_addr;
 	long long int number;
 	uint8_t bytes[256];
 	char *str;
@@ -353,6 +354,7 @@ static void proto_add(enum proto_id pid)
 %token K_DADDR K_SADDR K_ETYPE
 %token K_OPER K_SHA K_SPA K_THA K_TPA K_REQUEST K_REPLY K_PTYPE K_HTYPE
 %token K_PROT K_TTL K_DSCP K_ECN K_TOS K_LEN K_ID K_FLAGS K_FRAG K_IHL K_VER K_CSUM K_DF K_MF
+%token K_FLOW K_NEXT_HDR K_HOP_LIMIT
 %token K_SPORT K_DPORT
 %token K_SEQ K_ACK_SEQ K_DOFF K_CWR K_ECE K_URG K_ACK K_PSH K_RST K_SYN K_FIN K_WINDOW K_URG_PTR
 %token K_TPID K_TCI K_PCP K_DEI K_1Q K_1AD
@@ -361,17 +363,18 @@ static void proto_add(enum proto_id pid)
 %token K_ETH
 %token K_VLAN K_MPLS
 %token K_ARP
-%token K_IP4
+%token K_IP4 K_IP6
 %token K_UDP K_TCP
 
 %token ',' '{' '}' '(' ')' '[' ']' ':' '-' '+' '*' '/' '%' '&' '|' '<' '>' '^'
 
-%token number string mac ip4_addr
+%token number string mac ip4_addr ip6_addr
 
 %type <number> number expression
 %type <str> string
 %type <bytes> mac
 %type <ip4_addr> ip4_addr
+%type <ip6_addr> ip6_addr
 
 %left '-' '+' '*' '/' '%' '&' '|' '<' '>' '^'
 
@@ -587,6 +590,7 @@ proto
 	| mpls_proto { }
 	| arp_proto { }
 	| ip4_proto { }
+	| ip6_proto { }
 	| udp_proto { }
 	| tcp_proto { }
 	;
@@ -770,6 +774,44 @@ ip4
 	: K_IP4	{ proto_add(PROTO_IP4); }
 	;
 
+ip6_proto
+	: ip6 '(' ip6_param_list ')' { }
+	;
+
+ip6_param_list
+	: { }
+	| ip6_field { }
+	| ip6_field delimiter ip6_param_list { }
+	;
+
+ip6_hop_limit
+	: K_HOP_LIMIT { }
+	| K_TTL { }
+	;
+
+ip6_field
+	: K_VER skip_white '=' skip_white number
+		{ proto_field_set_be32(hdr, IP6_VER, $5); }
+	| K_TC skip_white '=' skip_white number
+		{ proto_field_set_be32(hdr, IP6_CLASS, $5); }
+	| K_FLOW skip_white '=' skip_white number
+		{ proto_field_set_be32(hdr, IP6_FLOW_LBL, $5); }
+	| K_LEN skip_white '=' skip_white number
+		{ proto_field_set_be16(hdr, IP6_LEN, $5); }
+	| K_NEXT_HDR skip_white '=' skip_white number
+		{ proto_field_set_u8(hdr, IP6_NEXT_HDR, $5); }
+	| ip6_hop_limit skip_white '=' skip_white number
+		{ proto_field_set_u8(hdr, IP6_HOP_LIMIT, $5); }
+	| K_SADDR skip_white '=' skip_white ip6_addr
+		{ proto_field_set_bytes(hdr, IP6_SADDR, (uint8_t *)&($5.s6_addr)); }
+	| K_DADDR skip_white '=' skip_white ip6_addr
+		{ proto_field_set_bytes(hdr, IP6_DADDR, (uint8_t *)&($5.s6_addr)); }
+	;
+
+ip6
+	: K_IP6	{ proto_add(PROTO_IP6); }
+	;
+
 udp_proto
 	: udp '(' udp_param_list ')' { }
 	;
diff --git a/trafgen_proto.c b/trafgen_proto.c
index e3704d8..1babba5 100644
--- a/trafgen_proto.c
+++ b/trafgen_proto.c
@@ -348,7 +348,6 @@ static void __proto_field_set_dev_ipv4(struct proto_hdr *hdr, uint32_t fid,
 {
 	struct sockaddr_storage ss = { };
 	struct sockaddr_in *ss4;
-	uint32_t ip_addr;
 	int ret;
 
 	if (proto_field_is_set(hdr, fid))
@@ -359,9 +358,7 @@ static void __proto_field_set_dev_ipv4(struct proto_hdr *hdr, uint32_t fid,
 		panic("Could not get device IPv4 address\n");
 
 	ss4 = (struct sockaddr_in *) &ss;
-	ip_addr = ss4->sin_addr.s_addr;
-
-	__proto_field_set_bytes(hdr, fid, (uint8_t *)&ip_addr, is_default, false);
+	__proto_field_set_bytes(hdr, fid, (uint8_t *)&ss4->sin_addr.s_addr, is_default, false);
 }
 
 void proto_field_set_dev_ipv4(struct proto_hdr *hdr, uint32_t fid)
@@ -374,6 +371,34 @@ void proto_field_set_default_dev_ipv4(struct proto_hdr *hdr, uint32_t fid)
 	__proto_field_set_dev_ipv4(hdr, fid, true);
 }
 
+static void __proto_field_set_dev_ipv6(struct proto_hdr *hdr, uint32_t fid,
+				       bool is_default)
+{
+	struct sockaddr_storage ss = { };
+	struct sockaddr_in6 *ss6;
+	int ret;
+
+	if (proto_field_is_set(hdr, fid))
+		return;
+
+	ret = device_address(hdr->ctx->dev, AF_INET6, &ss);
+	if (ret < 0)
+		panic("Could not get device IPv6 address\n");
+
+	ss6 = (struct sockaddr_in6 *) &ss;
+	__proto_field_set_bytes(hdr, fid, (uint8_t *)&ss6->sin6_addr.s6_addr, is_default, false);
+}
+
+void proto_field_set_dev_ipv6(struct proto_hdr *hdr, uint32_t fid)
+{
+	__proto_field_set_dev_ipv6(hdr, fid, false);
+}
+
+void proto_field_set_default_dev_ipv6(struct proto_hdr *hdr, uint32_t fid)
+{
+	__proto_field_set_dev_ipv6(hdr, fid, true);
+}
+
 void protos_init(const char *dev)
 {
 	struct proto_hdr *p;
diff --git a/trafgen_proto.h b/trafgen_proto.h
index 31ac1c8..cdcffdc 100644
--- a/trafgen_proto.h
+++ b/trafgen_proto.h
@@ -105,4 +105,7 @@ extern void proto_field_set_default_dev_mac(struct proto_hdr *hdr, uint32_t fid)
 extern void proto_field_set_dev_ipv4(struct proto_hdr *hdr, uint32_t fid);
 extern void proto_field_set_default_dev_ipv4(struct proto_hdr *hdr, uint32_t fid);
 
+extern void proto_field_set_dev_ipv6(struct proto_hdr *hdr, uint32_t fid);
+extern void proto_field_set_default_dev_ipv6(struct proto_hdr *hdr, uint32_t fid);
+
 #endif /* TRAFGEN_PROTO_H */