LXR qemu/include/net/eth.h

   1/*
   2 * QEMU network structures definitions and helper functions
   3 *
   4 * Copyright (c) 2012 Ravello Systems LTD (http://ravellosystems.com)
   5 *
   6 * Developed by Daynix Computing LTD (http://www.daynix.com)
   7 *
   8 * Portions developed by Free Software Foundation, Inc
   9 * Copyright (C) 1991-1997, 2001, 2003, 2006 Free Software Foundation, Inc.
  10 * See netinet/ip6.h and netinet/in.h (GNU C Library)
  11 *
  12 * Portions developed by Igor Kovalenko
  13 * Copyright (c) 2006 Igor Kovalenko
  14 * See hw/rtl8139.c (QEMU)
  15 *
  16 * Authors:
  17 * Dmitry Fleytman <dmitry@daynix.com>
  18 * Tamir Shomer <tamirs@daynix.com>
  19 * Yan Vugenfirer <yan@daynix.com>
  20 *
  21 * This work is licensed under the terms of the GNU GPL, version 2 or later.
  22 * See the COPYING file in the top-level directory.
  23 *
  24 */
  25
  26#ifndef QEMU_ETH_H
  27#define QEMU_ETH_H
  28
  29#include "qemu/bswap.h"
  30#include "qemu/iov.h"
  31
  32#define ETH_ALEN 6
  33#define ETH_HLEN 14
  34#define ETH_ZLEN 60     /* Min. octets in frame without FCS */
  35#define ETH_FCS_LEN 4
  36#define ETH_MTU 1500
  37
  38struct eth_header {
  39    uint8_t  h_dest[ETH_ALEN];   /* destination eth addr */
  40    uint8_t  h_source[ETH_ALEN]; /* source ether addr    */
  41    uint16_t h_proto;            /* packet type ID field */
  42};
  43
  44struct vlan_header {
  45    uint16_t  h_tci;     /* priority and VLAN ID  */
  46    uint16_t  h_proto;   /* encapsulated protocol */
  47};
  48
  49struct ip_header {
  50    uint8_t  ip_ver_len;     /* version and header length */
  51    uint8_t  ip_tos;         /* type of service */
  52    uint16_t ip_len;         /* total length */
  53    uint16_t ip_id;          /* identification */
  54    uint16_t ip_off;         /* fragment offset field */
  55    uint8_t  ip_ttl;         /* time to live */
  56    uint8_t  ip_p;           /* protocol */
  57    uint16_t ip_sum;         /* checksum */
  58    uint32_t ip_src, ip_dst; /* source and destination address */
  59} QEMU_PACKED;
  60
  61typedef struct tcp_header {
  62    uint16_t th_sport;          /* source port */
  63    uint16_t th_dport;          /* destination port */
  64    uint32_t th_seq;            /* sequence number */
  65    uint32_t th_ack;            /* acknowledgment number */
  66    uint16_t th_offset_flags;   /* data offset, reserved 6 bits, */
  67                                /* TCP protocol flags */
  68    uint16_t th_win;            /* window */
  69    uint16_t th_sum;            /* checksum */
  70    uint16_t th_urp;            /* urgent pointer */
  71} tcp_header;
  72
  73#define TCP_FLAGS_ONLY(flags) ((flags) & 0x3f)
  74
  75#define TCP_HEADER_FLAGS(tcp) \
  76    TCP_FLAGS_ONLY(be16_to_cpu((tcp)->th_offset_flags))
  77
  78#define TCP_FLAG_ACK  0x10
  79
  80#define TCP_HEADER_DATA_OFFSET(tcp) \
  81    (((be16_to_cpu((tcp)->th_offset_flags) >> 12) & 0xf) << 2)
  82
  83typedef struct udp_header {
  84    uint16_t uh_sport; /* source port */
  85    uint16_t uh_dport; /* destination port */
  86    uint16_t uh_ulen;  /* udp length */
  87    uint16_t uh_sum;   /* udp checksum */
  88} udp_header;
  89
  90typedef struct ip_pseudo_header {
  91    uint32_t ip_src;
  92    uint32_t ip_dst;
  93    uint8_t  zeros;
  94    uint8_t  ip_proto;
  95    uint16_t ip_payload;
  96} ip_pseudo_header;
  97
  98/* IPv6 address */
  99struct in6_address {
 100    union {
 101        uint8_t __u6_addr8[16];
 102    } __in6_u;
 103};
 104
 105struct ip6_header {
 106    union {
 107        struct ip6_hdrctl {
 108            uint32_t ip6_un1_flow; /* 4 bits version, 8 bits TC,
 109                                      20 bits flow-ID */
 110            uint16_t ip6_un1_plen; /* payload length */
 111            uint8_t  ip6_un1_nxt;  /* next header */
 112            uint8_t  ip6_un1_hlim; /* hop limit */
 113        } ip6_un1;
 114        uint8_t ip6_un2_vfc;       /* 4 bits version, top 4 bits tclass */
 115        struct ip6_ecn_access {
 116            uint8_t  ip6_un3_vfc;  /* 4 bits version, top 4 bits tclass */
 117            uint8_t  ip6_un3_ecn;  /* 2 bits ECN, top 6 bits payload length */
 118        } ip6_un3;
 119    } ip6_ctlun;
 120    struct in6_address ip6_src;    /* source address */
 121    struct in6_address ip6_dst;    /* destination address */
 122};
 123
 124typedef struct ip6_pseudo_header {
 125    struct in6_address ip6_src;
 126    struct in6_address ip6_dst;
 127    uint32_t           len;
 128    uint8_t            zero[3];
 129    uint8_t            next_hdr;
 130} ip6_pseudo_header;
 131
 132struct ip6_ext_hdr {
 133    uint8_t        ip6r_nxt;   /* next header */
 134    uint8_t        ip6r_len;   /* length in units of 8 octets */
 135};
 136
 137struct ip6_ext_hdr_routing {
 138    uint8_t     nxt;
 139    uint8_t     len;
 140    uint8_t     rtype;
 141    uint8_t     segleft;
 142    uint8_t     rsvd[4];
 143};
 144
 145struct ip6_option_hdr {
 146#define IP6_OPT_PAD1   (0x00)
 147#define IP6_OPT_HOME   (0xC9)
 148    uint8_t type;
 149    uint8_t len;
 150};
 151
 152struct udp_hdr {
 153  uint16_t uh_sport;           /* source port */
 154  uint16_t uh_dport;           /* destination port */
 155  uint16_t uh_ulen;            /* udp length */
 156  uint16_t uh_sum;             /* udp checksum */
 157};
 158
 159struct tcp_hdr {
 160    u_short     th_sport;   /* source port */
 161    u_short     th_dport;   /* destination port */
 162    uint32_t    th_seq;     /* sequence number */
 163    uint32_t    th_ack;     /* acknowledgment number */
 164#if HOST_BIG_ENDIAN
 165    u_char  th_off : 4,     /* data offset */
 166        th_x2:4;            /* (unused) */
 167#else
 168    u_char  th_x2 : 4,      /* (unused) */
 169        th_off:4;           /* data offset */
 170#endif
 171
 172#define TH_ELN  0x1 /* explicit loss notification */
 173#define TH_ECN  0x2 /* explicit congestion notification */
 174#define TH_FS   0x4 /* fast start */
 175
 176    u_char  th_flags;
 177#define TH_FIN  0x01
 178#define TH_SYN  0x02
 179#define TH_RST  0x04
 180#define TH_PUSH 0x08
 181#define TH_ACK  0x10
 182#define TH_URG  0x20
 183#define TH_ECE  0x40
 184#define TH_CWR  0x80
 185    u_short th_win;      /* window */
 186    u_short th_sum;      /* checksum */
 187    u_short th_urp;      /* urgent pointer */
 188};
 189
 190#define ip6_nxt      ip6_ctlun.ip6_un1.ip6_un1_nxt
 191#define ip6_ecn_acc  ip6_ctlun.ip6_un3.ip6_un3_ecn
 192#define ip6_plen     ip6_ctlun.ip6_un1.ip6_un1_plen
 193
 194#define PKT_GET_ETH_HDR(p)        \
 195    ((struct eth_header *)(p))
 196#define PKT_GET_VLAN_HDR(p)       \
 197    ((struct vlan_header *) (((uint8_t *)(p)) + sizeof(struct eth_header)))
 198#define PKT_GET_DVLAN_HDR(p)       \
 199    (PKT_GET_VLAN_HDR(p) + 1)
 200#define PKT_GET_IP_HDR(p)         \
 201    ((struct ip_header *)(((uint8_t *)(p)) + eth_get_l2_hdr_length(p)))
 202#define IP_HDR_GET_LEN(p)         \
 203    ((ldub_p(p + offsetof(struct ip_header, ip_ver_len)) & 0x0F) << 2)
 204#define IP_HDR_GET_P(p)                                           \
 205    (ldub_p(p + offsetof(struct ip_header, ip_p)))
 206#define PKT_GET_IP_HDR_LEN(p)     \
 207    (IP_HDR_GET_LEN(PKT_GET_IP_HDR(p)))
 208#define PKT_GET_IP6_HDR(p)        \
 209    ((struct ip6_header *) (((uint8_t *)(p)) + eth_get_l2_hdr_length(p)))
 210#define IP_HEADER_VERSION(ip)     \
 211    (((ip)->ip_ver_len >> 4) & 0xf)
 212#define IP4_IS_FRAGMENT(ip) \
 213    ((be16_to_cpu((ip)->ip_off) & (IP_OFFMASK | IP_MF)) != 0)
 214
 215#define ETH_P_IP                  (0x0800)      /* Internet Protocol packet  */
 216#define ETH_P_ARP                 (0x0806)      /* Address Resolution packet */
 217#define ETH_P_IPV6                (0x86dd)
 218#define ETH_P_VLAN                (0x8100)
 219#define ETH_P_DVLAN               (0x88a8)
 220#define ETH_P_NCSI                (0x88f8)
 221#define ETH_P_UNKNOWN             (0xffff)
 222#define VLAN_VID_MASK             0x0fff
 223#define IP_HEADER_VERSION_4       (4)
 224#define IP_HEADER_VERSION_6       (6)
 225#define IP_PROTO_TCP              (6)
 226#define IP_PROTO_UDP              (17)
 227#define IP_PROTO_SCTP             (132)
 228#define IPTOS_ECN_MASK            0x03
 229#define IPTOS_ECN(x)              ((x) & IPTOS_ECN_MASK)
 230#define IPTOS_ECN_CE              0x03
 231#define IP6_ECN_MASK              0xC0
 232#define IP6_ECN(x)                ((x) & IP6_ECN_MASK)
 233#define IP6_ECN_CE                0xC0
 234#define IP4_DONT_FRAGMENT_FLAG    (1 << 14)
 235
 236#define IS_SPECIAL_VLAN_ID(x)     \
 237    (((x) == 0) || ((x) == 0xFFF))
 238
 239#define ETH_MAX_L2_HDR_LEN  \
 240    (sizeof(struct eth_header) + 2 * sizeof(struct vlan_header))
 241
 242#define ETH_MAX_IP4_HDR_LEN   (60)
 243#define ETH_MAX_IP_DGRAM_LEN  (0xFFFF)
 244
 245#define IP_FRAG_UNIT_SIZE     (8)
 246#define IP_FRAG_ALIGN_SIZE(x) ((x) & ~0x7)
 247#define IP_RF                 0x8000           /* reserved fragment flag */
 248#define IP_DF                 0x4000           /* don't fragment flag */
 249#define IP_MF                 0x2000           /* more fragments flag */
 250#define IP_OFFMASK            0x1fff           /* mask for fragmenting bits */
 251
 252#define IP6_EXT_GRANULARITY   (8)  /* Size granularity for
 253                                      IPv6 extension headers */
 254
 255/* IP6 extension header types */
 256#define IP6_HOP_BY_HOP        (0)
 257#define IP6_ROUTING           (43)
 258#define IP6_FRAGMENT          (44)
 259#define IP6_ESP               (50)
 260#define IP6_AUTHENTICATION    (51)
 261#define IP6_NONE              (59)
 262#define IP6_DESTINATON        (60)
 263#define IP6_MOBILITY          (135)
 264
 265static inline int is_multicast_ether_addr(const uint8_t *addr)
 266{
 267    return 0x01 & addr[0];
 268}
 269
 270static inline int is_broadcast_ether_addr(const uint8_t *addr)
 271{
 272    return (addr[0] & addr[1] & addr[2] & addr[3] & addr[4] & addr[5]) == 0xff;
 273}
 274
 275static inline int is_unicast_ether_addr(const uint8_t *addr)
 276{
 277    return !is_multicast_ether_addr(addr);
 278}
 279
 280typedef enum {
 281    ETH_PKT_UCAST = 0xAABBCC00,
 282    ETH_PKT_BCAST,
 283    ETH_PKT_MCAST
 284} eth_pkt_types_e;
 285
 286static inline eth_pkt_types_e
 287get_eth_packet_type(const struct eth_header *ehdr)
 288{
 289    if (is_broadcast_ether_addr(ehdr->h_dest)) {
 290        return ETH_PKT_BCAST;
 291    } else if (is_multicast_ether_addr(ehdr->h_dest)) {
 292        return ETH_PKT_MCAST;
 293    } else { /* unicast */
 294        return ETH_PKT_UCAST;
 295    }
 296}
 297
 298static inline uint32_t
 299eth_get_l2_hdr_length(const void *p)
 300{
 301    uint16_t proto = be16_to_cpu(PKT_GET_ETH_HDR(p)->h_proto);
 302    struct vlan_header *hvlan = PKT_GET_VLAN_HDR(p);
 303    switch (proto) {
 304    case ETH_P_VLAN:
 305        return sizeof(struct eth_header) + sizeof(struct vlan_header);
 306    case ETH_P_DVLAN:
 307        if (be16_to_cpu(hvlan->h_proto) == ETH_P_VLAN) {
 308            return sizeof(struct eth_header) + 2 * sizeof(struct vlan_header);
 309        } else {
 310            return sizeof(struct eth_header) + sizeof(struct vlan_header);
 311        }
 312    default:
 313        return sizeof(struct eth_header);
 314    }
 315}
 316
 317static inline uint32_t
 318eth_get_l2_hdr_length_iov(const struct iovec *iov, size_t iovcnt, size_t iovoff)
 319{
 320    uint8_t p[sizeof(struct eth_header) + sizeof(struct vlan_header)];
 321    size_t copied = iov_to_buf(iov, iovcnt, iovoff, p, ARRAY_SIZE(p));
 322
 323    if (copied < ARRAY_SIZE(p)) {
 324        return copied;
 325    }
 326
 327    return eth_get_l2_hdr_length(p);
 328}
 329
 330static inline uint16_t
 331eth_get_pkt_tci(const void *p)
 332{
 333    uint16_t proto = be16_to_cpu(PKT_GET_ETH_HDR(p)->h_proto);
 334    struct vlan_header *hvlan = PKT_GET_VLAN_HDR(p);
 335    switch (proto) {
 336    case ETH_P_VLAN:
 337    case ETH_P_DVLAN:
 338        return be16_to_cpu(hvlan->h_tci);
 339    default:
 340        return 0;
 341    }
 342}
 343
 344size_t
 345eth_strip_vlan(const struct iovec *iov, int iovcnt, size_t iovoff,
 346               void *new_ehdr_buf,
 347               uint16_t *payload_offset, uint16_t *tci);
 348
 349size_t
 350eth_strip_vlan_ex(const struct iovec *iov, int iovcnt, size_t iovoff, int index,
 351                  uint16_t vet, uint16_t vet_ext, void *new_ehdr_buf,
 352                  uint16_t *payload_offset, uint16_t *tci);
 353
 354uint16_t
 355eth_get_l3_proto(const struct iovec *l2hdr_iov, int iovcnt, size_t l2hdr_len);
 356
 357void eth_setup_vlan_headers(struct eth_header *ehdr, size_t *ehdr_size,
 358                            uint16_t vlan_tag, uint16_t vlan_ethtype);
 359
 360
 361uint8_t eth_get_gso_type(uint16_t l3_proto, uint8_t *l3_hdr, uint8_t l4proto);
 362
 363typedef struct eth_ip6_hdr_info_st {
 364    uint8_t l4proto;
 365    size_t  full_hdr_len;
 366    struct  ip6_header ip6_hdr;
 367    bool    has_ext_hdrs;
 368    bool    rss_ex_src_valid;
 369    struct  in6_address rss_ex_src;
 370    bool    rss_ex_dst_valid;
 371    struct  in6_address rss_ex_dst;
 372    bool    fragment;
 373} eth_ip6_hdr_info;
 374
 375typedef struct eth_ip4_hdr_info_st {
 376    struct ip_header ip4_hdr;
 377    bool   fragment;
 378} eth_ip4_hdr_info;
 379
 380typedef enum EthL4HdrProto {
 381    ETH_L4_HDR_PROTO_INVALID,
 382    ETH_L4_HDR_PROTO_TCP,
 383    ETH_L4_HDR_PROTO_UDP,
 384    ETH_L4_HDR_PROTO_SCTP
 385} EthL4HdrProto;
 386
 387typedef struct eth_l4_hdr_info_st {
 388    union {
 389        struct tcp_header tcp;
 390        struct udp_header udp;
 391    } hdr;
 392
 393    EthL4HdrProto proto;
 394    bool has_tcp_data;
 395} eth_l4_hdr_info;
 396
 397void eth_get_protocols(const struct iovec *iov, size_t iovcnt, size_t iovoff,
 398                       bool *hasip4, bool *hasip6,
 399                       size_t *l3hdr_off,
 400                       size_t *l4hdr_off,
 401                       size_t *l5hdr_off,
 402                       eth_ip6_hdr_info *ip6hdr_info,
 403                       eth_ip4_hdr_info *ip4hdr_info,
 404                       eth_l4_hdr_info  *l4hdr_info);
 405
 406void
 407eth_fix_ip4_checksum(void *l3hdr, size_t l3hdr_len);
 408
 409uint32_t
 410eth_calc_ip4_pseudo_hdr_csum(struct ip_header *iphdr,
 411                             uint16_t csl,
 412                             uint32_t *cso);
 413
 414uint32_t
 415eth_calc_ip6_pseudo_hdr_csum(struct ip6_header *iphdr,
 416                             uint16_t csl,
 417                             uint8_t l4_proto,
 418                             uint32_t *cso);
 419
 420bool
 421eth_parse_ipv6_hdr(const struct iovec *pkt, int pkt_frags,
 422                   size_t ip6hdr_off, eth_ip6_hdr_info *info);
 423
 424/**
 425 * eth_pad_short_frame - pad a short frame to the minimum Ethernet frame length
 426 *
 427 * If the Ethernet frame size is shorter than 60 bytes, it will be padded to
 428 * 60 bytes at the address @padded_pkt.
 429 *
 430 * @padded_pkt: buffer address to hold the padded frame
 431 * @padded_buflen: pointer holding length of @padded_pkt. If the frame is
 432 *                 padded, the length will be updated to the padded one.
 433 * @pkt: address to hold the original Ethernet frame
 434 * @pkt_size: size of the original Ethernet frame
 435 * @return true if the frame is padded, otherwise false
 436 */
 437bool eth_pad_short_frame(uint8_t *padded_pkt, size_t *padded_buflen,
 438                         const void *pkt, size_t pkt_size);
 439
 440#endif
 441