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Diffstat (limited to 'lib/packets.h')
| -rw-r--r-- | lib/packets.h | 274 |
1 files changed, 274 insertions, 0 deletions
diff --git a/lib/packets.h b/lib/packets.h new file mode 100644 index 000000000..c1ae621ea --- /dev/null +++ b/lib/packets.h @@ -0,0 +1,274 @@ +/* + * Copyright (c) 2008, 2009 Nicira Networks. + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +#ifndef PACKETS_H +#define PACKETS_H 1 + +#include <stdint.h> +#include <string.h> +#include "compiler.h" +#include "random.h" +#include "util.h" + +#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); +} + +#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] + +#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 */ |