[mirror_ovs.git] / lib / packets.h

/*
 * Copyright (c) 2008, 2009 Nicira Networks.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef PACKETS_H
#define PACKETS_H 1

#include <inttypes.h>
#include <stdint.h>
#include <string.h>
#include "compiler.h"
#include "random.h"
#include "util.h"

struct ofpbuf;

#define ETH_ADDR_LEN           6

static const uint8_t eth_addr_broadcast[ETH_ADDR_LEN] UNUSED
    = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };

static inline bool eth_addr_is_broadcast(const uint8_t ea[6])
{
    return (ea[0] & ea[1] & ea[2] & ea[3] & ea[4] & ea[5]) == 0xff;
}

/* Returns true if 'ea' is an Ethernet address used for virtual interfaces
 * under XenServer.  Generally the actual Ethernet address is FE:FF:FF:FF:FF:FF
 * but it can be FE:FE:FE:FE:FE:FE in some cases. */
static inline bool eth_addr_is_vif(const uint8_t ea[6])
{
    return ea[0] == 0xfe && (ea[1] & ea[2] & ea[3] & ea[4] & ea[5]) >= 0xfe;
}

static inline bool eth_addr_is_multicast(const uint8_t ea[6])
{
    return ea[0] & 1;
}
static inline bool eth_addr_is_local(const uint8_t ea[6]) 
{
    return ea[0] & 2;
}
static inline bool eth_addr_is_zero(const uint8_t ea[6]) 
{
    return !(ea[0] | ea[1] | ea[2] | ea[3] | ea[4] | ea[5]);
}
static inline bool eth_addr_equals(const uint8_t a[ETH_ADDR_LEN],
                                   const uint8_t b[ETH_ADDR_LEN]) 
{
    return !memcmp(a, b, ETH_ADDR_LEN);
}
static inline uint64_t eth_addr_to_uint64(const uint8_t ea[ETH_ADDR_LEN])
{
    return (((uint64_t) ea[0] << 40)
            | ((uint64_t) ea[1] << 32)
            | ((uint64_t) ea[2] << 24)
            | ((uint64_t) ea[3] << 16)
            | ((uint64_t) ea[4] << 8)
            | ea[5]);
}
static inline void eth_addr_from_uint64(uint64_t x, uint8_t ea[ETH_ADDR_LEN])
{
    ea[0] = x >> 40;
    ea[1] = x >> 32;
    ea[2] = x >> 24;
    ea[3] = x >> 16;
    ea[4] = x >> 8;
    ea[5] = x;
}
static inline void eth_addr_mark_random(uint8_t ea[ETH_ADDR_LEN])
{
    ea[0] &= ~1;                /* Unicast. */
    ea[0] |= 2;                 /* Private. */
}
static inline void eth_addr_random(uint8_t ea[ETH_ADDR_LEN])
{
    random_bytes(ea, ETH_ADDR_LEN);
    eth_addr_mark_random(ea);
}
/* Returns true if 'ea' is a reserved multicast address, that a bridge must
 * never forward, false otherwise. */
static inline bool eth_addr_is_reserved(const uint8_t ea[ETH_ADDR_LEN])
{
    return (ea[0] == 0x01
            && ea[1] == 0x80
            && ea[2] == 0xc2
            && ea[3] == 0x00
            && ea[4] == 0x00
            && (ea[5] & 0xf0) == 0x00);
}

void compose_benign_packet(struct ofpbuf *, const char *tag,
                           uint16_t snap_type,
                           const uint8_t eth_src[ETH_ADDR_LEN]);

/* Example:
 *
 * uint8_t mac[ETH_ADDR_LEN];
 *    [...]
 * printf("The Ethernet address is "ETH_ADDR_FMT"\n", ETH_ADDR_ARGS(mac));
 *
 */
#define ETH_ADDR_FMT                                                    \
    "%02"PRIx8":%02"PRIx8":%02"PRIx8":%02"PRIx8":%02"PRIx8":%02"PRIx8
#define ETH_ADDR_ARGS(ea)                                   \
    (ea)[0], (ea)[1], (ea)[2], (ea)[3], (ea)[4], (ea)[5]

/* Example:
 *
 * char *string = "1 00:11:22:33:44:55 2";
 * uint8_t mac[ETH_ADDR_LEN];
 * int a, b;
 *
 * if (sscanf(string, "%d"ETH_ADDR_SCAN_FMT"%d",
 *     &a, ETH_ADDR_SCAN_ARGS(mac), &b) == 1 + ETH_ADDR_SCAN_COUNT + 1) {
 *     ...
 * }
 */
#define ETH_ADDR_SCAN_FMT "%"SCNx8":%"SCNx8":%"SCNx8":%"SCNx8":%"SCNx8":%"SCNx8
#define ETH_ADDR_SCAN_ARGS(ea) \
        &(ea)[0], &(ea)[1], &(ea)[2], &(ea)[3], &(ea)[4], &(ea)[5]
#define ETH_ADDR_SCAN_COUNT 6

#define ETH_TYPE_IP            0x0800
#define ETH_TYPE_ARP           0x0806
#define ETH_TYPE_VLAN          0x8100

#define ETH_HEADER_LEN 14
#define ETH_PAYLOAD_MIN 46
#define ETH_PAYLOAD_MAX 1500
#define ETH_TOTAL_MIN (ETH_HEADER_LEN + ETH_PAYLOAD_MIN)
#define ETH_TOTAL_MAX (ETH_HEADER_LEN + ETH_PAYLOAD_MAX)
#define ETH_VLAN_TOTAL_MAX (ETH_HEADER_LEN + VLAN_HEADER_LEN + ETH_PAYLOAD_MAX)
struct eth_header {
    uint8_t eth_dst[ETH_ADDR_LEN];
    uint8_t eth_src[ETH_ADDR_LEN];
    uint16_t eth_type;
} __attribute__((packed));
BUILD_ASSERT_DECL(ETH_HEADER_LEN == sizeof(struct eth_header));

#define LLC_DSAP_SNAP 0xaa
#define LLC_SSAP_SNAP 0xaa
#define LLC_CNTL_SNAP 3

#define LLC_HEADER_LEN 3
struct llc_header {
    uint8_t llc_dsap;
    uint8_t llc_ssap;
    uint8_t llc_cntl;
} __attribute__((packed));
BUILD_ASSERT_DECL(LLC_HEADER_LEN == sizeof(struct llc_header));

#define SNAP_ORG_ETHERNET "\0\0" /* The compiler adds a null byte, so
                                    sizeof(SNAP_ORG_ETHERNET) == 3. */
#define SNAP_HEADER_LEN 5
struct snap_header {
    uint8_t snap_org[3];
    uint16_t snap_type;
} __attribute__((packed));
BUILD_ASSERT_DECL(SNAP_HEADER_LEN == sizeof(struct snap_header));

#define LLC_SNAP_HEADER_LEN (LLC_HEADER_LEN + SNAP_HEADER_LEN)
struct llc_snap_header {
    struct llc_header llc;
    struct snap_header snap;
} __attribute__((packed));
BUILD_ASSERT_DECL(LLC_SNAP_HEADER_LEN == sizeof(struct llc_snap_header));

#define VLAN_VID_MASK 0x0fff
#define VLAN_PCP_MASK 0xe000

#define VLAN_HEADER_LEN 4
struct vlan_header {
    uint16_t vlan_tci;          /* Lowest 12 bits are VLAN ID. */
    uint16_t vlan_next_type;
};
BUILD_ASSERT_DECL(VLAN_HEADER_LEN == sizeof(struct vlan_header));

#define VLAN_ETH_HEADER_LEN (ETH_HEADER_LEN + VLAN_HEADER_LEN)
struct vlan_eth_header {
    uint8_t veth_dst[ETH_ADDR_LEN];
    uint8_t veth_src[ETH_ADDR_LEN];
    uint16_t veth_type;         /* Always htons(ETH_TYPE_VLAN). */
    uint16_t veth_tci;          /* Lowest 12 bits are VLAN ID. */
    uint16_t veth_next_type;
} __attribute__((packed));
BUILD_ASSERT_DECL(VLAN_ETH_HEADER_LEN == sizeof(struct vlan_eth_header));

/* The "(void) (ip)[0]" below has no effect on the value, since it's the first
 * argument of a comma expression, but it makes sure that 'ip' is a pointer.
 * This is useful since a common mistake is to pass an integer instead of a
 * pointer to IP_ARGS. */
#define IP_FMT "%"PRIu8".%"PRIu8".%"PRIu8".%"PRIu8
#define IP_ARGS(ip)                             \
        ((void) (ip)[0], ((uint8_t *) ip)[0]),  \
        ((uint8_t *) ip)[1],                    \
        ((uint8_t *) ip)[2],                    \
        ((uint8_t *) ip)[3]

#define IP_VER(ip_ihl_ver) ((ip_ihl_ver) >> 4)
#define IP_IHL(ip_ihl_ver) ((ip_ihl_ver) & 15)
#define IP_IHL_VER(ihl, ver) (((ver) << 4) | (ihl))

#define IP_TYPE_ICMP 1
#define IP_TYPE_TCP 6
#define IP_TYPE_UDP 17

#define IP_VERSION 4

#define IP_DONT_FRAGMENT  0x4000 /* Don't fragment. */
#define IP_MORE_FRAGMENTS 0x2000 /* More fragments. */
#define IP_FRAG_OFF_MASK  0x1fff /* Fragment offset. */
#define IP_IS_FRAGMENT(ip_frag_off) \
        ((ip_frag_off) & htons(IP_MORE_FRAGMENTS | IP_FRAG_OFF_MASK))

#define IP_HEADER_LEN 20
struct ip_header {
    uint8_t ip_ihl_ver;
    uint8_t ip_tos;
    uint16_t ip_tot_len;
    uint16_t ip_id;
    uint16_t ip_frag_off;
    uint8_t ip_ttl;
    uint8_t ip_proto;
    uint16_t ip_csum;
    uint32_t ip_src;
    uint32_t ip_dst;
};
BUILD_ASSERT_DECL(IP_HEADER_LEN == sizeof(struct ip_header));

#define ICMP_HEADER_LEN 4
struct icmp_header {
    uint8_t icmp_type;
    uint8_t icmp_code;
    uint16_t icmp_csum;
};
BUILD_ASSERT_DECL(ICMP_HEADER_LEN == sizeof(struct icmp_header));

#define UDP_HEADER_LEN 8
struct udp_header {
    uint16_t udp_src;
    uint16_t udp_dst;
    uint16_t udp_len;
    uint16_t udp_csum;
};
BUILD_ASSERT_DECL(UDP_HEADER_LEN == sizeof(struct udp_header));

#define TCP_FIN 0x01
#define TCP_SYN 0x02
#define TCP_RST 0x04
#define TCP_PSH 0x08
#define TCP_ACK 0x10
#define TCP_URG 0x20

#define TCP_FLAGS(tcp_ctl) (htons(tcp_ctl) & 0x003f)
#define TCP_OFFSET(tcp_ctl) (htons(tcp_ctl) >> 12)

#define TCP_HEADER_LEN 20
struct tcp_header {
    uint16_t tcp_src;
    uint16_t tcp_dst;
    uint32_t tcp_seq;
    uint32_t tcp_ack;
    uint16_t tcp_ctl;
    uint16_t tcp_winsz;
    uint16_t tcp_csum;
    uint16_t tcp_urg;
};
BUILD_ASSERT_DECL(TCP_HEADER_LEN == sizeof(struct tcp_header));

#define ARP_HRD_ETHERNET 1
#define ARP_PRO_IP 0x0800
#define ARP_OP_REQUEST 1
#define ARP_OP_REPLY 2

#define ARP_ETH_HEADER_LEN 28
struct arp_eth_header {
    /* Generic members. */
    uint16_t ar_hrd;           /* Hardware type. */
    uint16_t ar_pro;           /* Protocol type. */
    uint8_t ar_hln;            /* Hardware address length. */
    uint8_t ar_pln;            /* Protocol address length. */
    uint16_t ar_op;            /* Opcode. */

    /* Ethernet+IPv4 specific members. */
    uint8_t ar_sha[ETH_ADDR_LEN]; /* Sender hardware address. */
    uint32_t ar_spa;           /* Sender protocol address. */
    uint8_t ar_tha[ETH_ADDR_LEN]; /* Target hardware address. */
    uint32_t ar_tpa;           /* Target protocol address. */
} __attribute__((packed));
BUILD_ASSERT_DECL(ARP_ETH_HEADER_LEN == sizeof(struct arp_eth_header));

#endif /* packets.h */
Commit	Line	Data
064af421 BP	1	/*
	2	* Copyright (c) 2008, 2009 Nicira Networks.
	3	*
a14bc59f BP	4	* Licensed under the Apache License, Version 2.0 (the "License");
	5	* you may not use this file except in compliance with the License.
	6	* You may obtain a copy of the License at:
064af421	7	*
a14bc59f BP	8	* http://www.apache.org/licenses/LICENSE-2.0
	9	*
	10	* Unless required by applicable law or agreed to in writing, software
	11	* distributed under the License is distributed on an "AS IS" BASIS,
	12	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	13	* See the License for the specific language governing permissions and
	14	* limitations under the License.
064af421	15	*/
b9e8b45a	16
064af421 BP	17	#ifndef PACKETS_H
	18	#define PACKETS_H 1
	19
ab9c78ff	20	#include <inttypes.h>
064af421 BP	21	#include <stdint.h>
	22	#include <string.h>
	23	#include "compiler.h"
	24	#include "random.h"
	25	#include "util.h"
	26
b9e8b45a BP	27	struct ofpbuf;
b9e8b45a BP	28
064af421 BP	29	#define ETH_ADDR_LEN 6
	30
	31	static const uint8_t eth_addr_broadcast[ETH_ADDR_LEN] UNUSED
	32	= { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
	33
	34	static inline bool eth_addr_is_broadcast(const uint8_t ea[6])
	35	{
	36	return (ea[0] & ea[1] & ea[2] & ea[3] & ea[4] & ea[5]) == 0xff;
	37	}
	38
	39	/* Returns true if 'ea' is an Ethernet address used for virtual interfaces
	40	* under XenServer. Generally the actual Ethernet address is FE:FF:FF:FF:FF:FF
	41	* but it can be FE:FE:FE:FE:FE:FE in some cases. */
	42	static inline bool eth_addr_is_vif(const uint8_t ea[6])
	43	{
	44	return ea[0] == 0xfe && (ea[1] & ea[2] & ea[3] & ea[4] & ea[5]) >= 0xfe;
	45	}
	46
	47	static inline bool eth_addr_is_multicast(const uint8_t ea[6])
	48	{
	49	return ea[0] & 1;
	50	}
	51	static inline bool eth_addr_is_local(const uint8_t ea[6])
	52	{
	53	return ea[0] & 2;
	54	}
	55	static inline bool eth_addr_is_zero(const uint8_t ea[6])
	56	{
	57	return !(ea[0] \| ea[1] \| ea[2] \| ea[3] \| ea[4] \| ea[5]);
	58	}
	59	static inline bool eth_addr_equals(const uint8_t a[ETH_ADDR_LEN],
	60	const uint8_t b[ETH_ADDR_LEN])
	61	{
	62	return !memcmp(a, b, ETH_ADDR_LEN);
	63	}
	64	static inline uint64_t eth_addr_to_uint64(const uint8_t ea[ETH_ADDR_LEN])
	65	{
	66	return (((uint64_t) ea[0] << 40)
	67	\| ((uint64_t) ea[1] << 32)
	68	\| ((uint64_t) ea[2] << 24)
	69	\| ((uint64_t) ea[3] << 16)
	70	\| ((uint64_t) ea[4] << 8)
	71	\| ea[5]);
	72	}
	73	static inline void eth_addr_from_uint64(uint64_t x, uint8_t ea[ETH_ADDR_LEN])
	74	{
	75	ea[0] = x >> 40;
	76	ea[1] = x >> 32;
	77	ea[2] = x >> 24;
	78	ea[3] = x >> 16;
	79	ea[4] = x >> 8;
	80	ea[5] = x;
	81	}
	82	static inline void eth_addr_mark_random(uint8_t ea[ETH_ADDR_LEN])
	83	{
	84	ea[0] &= ~1; /* Unicast. */
	85	ea[0] \|= 2; /* Private. */
	86	}
	87	static inline void eth_addr_random(uint8_t ea[ETH_ADDR_LEN])
	88	{
	89	random_bytes(ea, ETH_ADDR_LEN);
	90	eth_addr_mark_random(ea);
	91	}
	92	/* Returns true if 'ea' is a reserved multicast address, that a bridge must
93	* never forward, false otherwise. */
94	static inline bool eth_addr_is_reserved(const uint8_t ea[ETH_ADDR_LEN])
95	{
96	return (ea[0] == 0x01
97	&& ea[1] == 0x80
98	&& ea[2] == 0xc2
99	&& ea[3] == 0x00
100	&& ea[4] == 0x00
101	&& (ea[5] & 0xf0) == 0x00);
102	}
103
b9e8b45a BP	104	void compose_benign_packet(struct ofpbuf , const char tag,
	105	uint16_t snap_type,
	106	const uint8_t eth_src[ETH_ADDR_LEN]);
	107
eaa71334 BP	108	/* Example:
	109	*
	110	* uint8_t mac[ETH_ADDR_LEN];
	111	* [...]
	112	* printf("The Ethernet address is "ETH_ADDR_FMT"\n", ETH_ADDR_ARGS(mac));
	113	*
	114	*/
064af421 BP	115	#define ETH_ADDR_FMT \
	116	"%02"PRIx8":%02"PRIx8":%02"PRIx8":%02"PRIx8":%02"PRIx8":%02"PRIx8
	117	#define ETH_ADDR_ARGS(ea) \
	118	(ea)[0], (ea)[1], (ea)[2], (ea)[3], (ea)[4], (ea)[5]
	119
eaa71334 BP	120	/* Example:
	121	*
	122	* char *string = "1 00:11:22:33:44:55 2";
	123	* uint8_t mac[ETH_ADDR_LEN];
	124	* int a, b;
	125	*
	126	* if (sscanf(string, "%d"ETH_ADDR_SCAN_FMT"%d",
	127	* &a, ETH_ADDR_SCAN_ARGS(mac), &b) == 1 + ETH_ADDR_SCAN_COUNT + 1) {
	128	* ...
	129	* }
	130	*/
	131	#define ETH_ADDR_SCAN_FMT "%"SCNx8":%"SCNx8":%"SCNx8":%"SCNx8":%"SCNx8":%"SCNx8
	132	#define ETH_ADDR_SCAN_ARGS(ea) \
	133	&(ea)[0], &(ea)[1], &(ea)[2], &(ea)[3], &(ea)[4], &(ea)[5]
	134	#define ETH_ADDR_SCAN_COUNT 6
	135
064af421 BP	136	#define ETH_TYPE_IP 0x0800
	137	#define ETH_TYPE_ARP 0x0806
	138	#define ETH_TYPE_VLAN 0x8100
	139
	140	#define ETH_HEADER_LEN 14
	141	#define ETH_PAYLOAD_MIN 46
	142	#define ETH_PAYLOAD_MAX 1500
	143	#define ETH_TOTAL_MIN (ETH_HEADER_LEN + ETH_PAYLOAD_MIN)
	144	#define ETH_TOTAL_MAX (ETH_HEADER_LEN + ETH_PAYLOAD_MAX)
	145	#define ETH_VLAN_TOTAL_MAX (ETH_HEADER_LEN + VLAN_HEADER_LEN + ETH_PAYLOAD_MAX)
	146	struct eth_header {
	147	uint8_t eth_dst[ETH_ADDR_LEN];
	148	uint8_t eth_src[ETH_ADDR_LEN];
	149	uint16_t eth_type;
	150	} __attribute__((packed));
	151	BUILD_ASSERT_DECL(ETH_HEADER_LEN == sizeof(struct eth_header));
	152
	153	#define LLC_DSAP_SNAP 0xaa
	154	#define LLC_SSAP_SNAP 0xaa
	155	#define LLC_CNTL_SNAP 3
	156
	157	#define LLC_HEADER_LEN 3
	158	struct llc_header {
	159	uint8_t llc_dsap;
	160	uint8_t llc_ssap;
	161	uint8_t llc_cntl;
	162	} __attribute__((packed));
	163	BUILD_ASSERT_DECL(LLC_HEADER_LEN == sizeof(struct llc_header));
	164
	165	#define SNAP_ORG_ETHERNET "\0\0" /* The compiler adds a null byte, so
	166	sizeof(SNAP_ORG_ETHERNET) == 3. */
	167	#define SNAP_HEADER_LEN 5
	168	struct snap_header {
	169	uint8_t snap_org[3];
	170	uint16_t snap_type;
	171	} __attribute__((packed));
	172	BUILD_ASSERT_DECL(SNAP_HEADER_LEN == sizeof(struct snap_header));
	173
	174	#define LLC_SNAP_HEADER_LEN (LLC_HEADER_LEN + SNAP_HEADER_LEN)
	175	struct llc_snap_header {
	176	struct llc_header llc;
	177	struct snap_header snap;
	178	} __attribute__((packed));
	179	BUILD_ASSERT_DECL(LLC_SNAP_HEADER_LEN == sizeof(struct llc_snap_header));
	180
	181	#define VLAN_VID_MASK 0x0fff
	182	#define VLAN_PCP_MASK 0xe000
	183
	184	#define VLAN_HEADER_LEN 4
	185	struct vlan_header {
	186	uint16_t vlan_tci; /* Lowest 12 bits are VLAN ID. */
	187	uint16_t vlan_next_type;
	188	};
	189	BUILD_ASSERT_DECL(VLAN_HEADER_LEN == sizeof(struct vlan_header));
	190
	191	#define VLAN_ETH_HEADER_LEN (ETH_HEADER_LEN + VLAN_HEADER_LEN)
	192	struct vlan_eth_header {
	193	uint8_t veth_dst[ETH_ADDR_LEN];
	194	uint8_t veth_src[ETH_ADDR_LEN];
	195	uint16_t veth_type; /* Always htons(ETH_TYPE_VLAN). */
	196	uint16_t veth_tci; /* Lowest 12 bits are VLAN ID. */
	197	uint16_t veth_next_type;
	198	} __attribute__((packed));
	199	BUILD_ASSERT_DECL(VLAN_ETH_HEADER_LEN == sizeof(struct vlan_eth_header));
200
201	/* The "(void) (ip)[0]" below has no effect on the value, since it's the first
202	* argument of a comma expression, but it makes sure that 'ip' is a pointer.
203	* This is useful since a common mistake is to pass an integer instead of a
204	* pointer to IP_ARGS. */
205	#define IP_FMT "%"PRIu8".%"PRIu8".%"PRIu8".%"PRIu8
206	#define IP_ARGS(ip) \
207	((void) (ip)[0], ((uint8_t *) ip)[0]), \
208	((uint8_t *) ip)[1], \
209	((uint8_t *) ip)[2], \
210	((uint8_t *) ip)[3]
211
212	#define IP_VER(ip_ihl_ver) ((ip_ihl_ver) >> 4)
213	#define IP_IHL(ip_ihl_ver) ((ip_ihl_ver) & 15)
214	#define IP_IHL_VER(ihl, ver) (((ver) << 4) \| (ihl))
215
216	#define IP_TYPE_ICMP 1
217	#define IP_TYPE_TCP 6
218	#define IP_TYPE_UDP 17
219
220	#define IP_VERSION 4
221
222	#define IP_DONT_FRAGMENT 0x4000 /* Don't fragment. */
223	#define IP_MORE_FRAGMENTS 0x2000 /* More fragments. */
224	#define IP_FRAG_OFF_MASK 0x1fff /* Fragment offset. */
225	#define IP_IS_FRAGMENT(ip_frag_off) \
226	((ip_frag_off) & htons(IP_MORE_FRAGMENTS \| IP_FRAG_OFF_MASK))
227
228	#define IP_HEADER_LEN 20
229	struct ip_header {
230	uint8_t ip_ihl_ver;
231	uint8_t ip_tos;
232	uint16_t ip_tot_len;
233	uint16_t ip_id;
234	uint16_t ip_frag_off;
235	uint8_t ip_ttl;
236	uint8_t ip_proto;
237	uint16_t ip_csum;
238	uint32_t ip_src;
239	uint32_t ip_dst;
240	};
241	BUILD_ASSERT_DECL(IP_HEADER_LEN == sizeof(struct ip_header));
242
243	#define ICMP_HEADER_LEN 4
244	struct icmp_header {
245	uint8_t icmp_type;
246	uint8_t icmp_code;
247	uint16_t icmp_csum;
248	};
249	BUILD_ASSERT_DECL(ICMP_HEADER_LEN == sizeof(struct icmp_header));
250
251	#define UDP_HEADER_LEN 8
252	struct udp_header {
253	uint16_t udp_src;
254	uint16_t udp_dst;
255	uint16_t udp_len;
256	uint16_t udp_csum;
257	};
258	BUILD_ASSERT_DECL(UDP_HEADER_LEN == sizeof(struct udp_header));
259
260	#define TCP_FIN 0x01
261	#define TCP_SYN 0x02
262	#define TCP_RST 0x04
263	#define TCP_PSH 0x08
264	#define TCP_ACK 0x10
265	#define TCP_URG 0x20
266
267	#define TCP_FLAGS(tcp_ctl) (htons(tcp_ctl) & 0x003f)
268	#define TCP_OFFSET(tcp_ctl) (htons(tcp_ctl) >> 12)
269
270	#define TCP_HEADER_LEN 20
271	struct tcp_header {
272	uint16_t tcp_src;
273	uint16_t tcp_dst;
274	uint32_t tcp_seq;
275	uint32_t tcp_ack;
276	uint16_t tcp_ctl;
277	uint16_t tcp_winsz;
278	uint16_t tcp_csum;
279	uint16_t tcp_urg;
280	};
281	BUILD_ASSERT_DECL(TCP_HEADER_LEN == sizeof(struct tcp_header));
282
283	#define ARP_HRD_ETHERNET 1
284	#define ARP_PRO_IP 0x0800
285	#define ARP_OP_REQUEST 1
286	#define ARP_OP_REPLY 2
287
288	#define ARP_ETH_HEADER_LEN 28
289	struct arp_eth_header {
290	/* Generic members. */
291	uint16_t ar_hrd; /* Hardware type. */
292	uint16_t ar_pro; /* Protocol type. */
293	uint8_t ar_hln; /* Hardware address length. */
294	uint8_t ar_pln; /* Protocol address length. */
295	uint16_t ar_op; /* Opcode. */
296
297	/* Ethernet+IPv4 specific members. */
298	uint8_t ar_sha[ETH_ADDR_LEN]; /* Sender hardware address. */
299	uint32_t ar_spa; /* Sender protocol address. */
300	uint8_t ar_tha[ETH_ADDR_LEN]; /* Target hardware address. */
301	uint32_t ar_tpa; /* Target protocol address. */
302	} __attribute__((packed));
303	BUILD_ASSERT_DECL(ARP_ETH_HEADER_LEN == sizeof(struct arp_eth_header));
304
305	#endif /* packets.h */