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
  35 struct eth_header {
  36     uint8_t  h_dest[ETH_ALEN];   /* destination eth addr */
  37     uint8_t  h_source[ETH_ALEN]; /* source ether addr    */
  38     uint16_t h_proto;            /* packet type ID field */
  39 };
  40
  41 struct vlan_header {
  42     uint16_t  h_tci;     /* priority and VLAN ID  */
  43     uint16_t  h_proto;   /* encapsulated protocol */
  44 };
  45
  46 struct ip_header {
  47     uint8_t  ip_ver_len;     /* version and header length */
  48     uint8_t  ip_tos;         /* type of service */
  49     uint16_t ip_len;         /* total length */
  50     uint16_t ip_id;          /* identification */
  51     uint16_t ip_off;         /* fragment offset field */
  52     uint8_t  ip_ttl;         /* time to live */
  53     uint8_t  ip_p;           /* protocol */
  54     uint16_t ip_sum;         /* checksum */
  55     uint32_t ip_src, ip_dst; /* source and destination address */
  56 };
  57
  58 typedef struct tcp_header {
  59     uint16_t th_sport;          /* source port */
  60     uint16_t th_dport;          /* destination port */
  61     uint32_t th_seq;            /* sequence number */
  62     uint32_t th_ack;            /* acknowledgment number */
  63     uint16_t th_offset_flags;   /* data offset, reserved 6 bits, */
  64                                 /* TCP protocol flags */
  65     uint16_t th_win;            /* window */
  66     uint16_t th_sum;            /* checksum */
  67     uint16_t th_urp;            /* urgent pointer */
  68 } tcp_header;
  69
  70 #define TCP_FLAGS_ONLY(flags) ((flags) & 0x3f)
  71
  72 #define TCP_HEADER_FLAGS(tcp) \
  73     TCP_FLAGS_ONLY(be16_to_cpu((tcp)->th_offset_flags))
  74
  75 #define TCP_FLAG_ACK  0x10
  76
  77 #define TCP_HEADER_DATA_OFFSET(tcp) \
  78     (((be16_to_cpu((tcp)->th_offset_flags) >> 12) & 0xf) << 2)
  79
  80 typedef struct udp_header {
  81     uint16_t uh_sport; /* source port */
  82     uint16_t uh_dport; /* destination port */
  83     uint16_t uh_ulen;  /* udp length */
  84     uint16_t uh_sum;   /* udp checksum */
  85 } udp_header;
  86
  87 typedef struct ip_pseudo_header {
  88     uint32_t ip_src;
  89     uint32_t ip_dst;
  90     uint8_t  zeros;
  91     uint8_t  ip_proto;
  92     uint16_t ip_payload;
  93 } ip_pseudo_header;
  94
  95 /* IPv6 address */
  96 struct in6_address {
  97     union {
  98         uint8_t __u6_addr8[16];
  99     } __in6_u;
 100 };
 101
 102 struct ip6_header {
 103     union {
 104         struct ip6_hdrctl {
 105             uint32_t ip6_un1_flow; /* 4 bits version, 8 bits TC,
 106                                       20 bits flow-ID */
 107             uint16_t ip6_un1_plen; /* payload length */
 108             uint8_t  ip6_un1_nxt;  /* next header */
 109             uint8_t  ip6_un1_hlim; /* hop limit */
 110         } ip6_un1;
 111         uint8_t ip6_un2_vfc;       /* 4 bits version, top 4 bits tclass */
 112         struct ip6_ecn_access {
 113             uint8_t  ip6_un3_vfc;  /* 4 bits version, top 4 bits tclass */
 114             uint8_t  ip6_un3_ecn;  /* 2 bits ECN, top 6 bits payload length */
 115         } ip6_un3;
 116     } ip6_ctlun;
 117     struct in6_address ip6_src;    /* source address */
 118     struct in6_address ip6_dst;    /* destination address */
 119 };
 120
 121 typedef struct ip6_pseudo_header {
 122     struct in6_address ip6_src;
 123     struct in6_address ip6_dst;
 124     uint32_t           len;
 125     uint8_t            zero[3];
 126     uint8_t            next_hdr;
 127 } ip6_pseudo_header;
 128
 129 struct ip6_ext_hdr {
 130     uint8_t        ip6r_nxt;   /* next header */
 131     uint8_t        ip6r_len;   /* length in units of 8 octets */
 132 };
 133
 134 struct ip6_ext_hdr_routing {
 135     uint8_t     nxt;
 136     uint8_t     len;
 137     uint8_t     rtype;
 138     uint8_t     segleft;
 139     uint8_t     rsvd[4];
 140 };
 141
 142 struct ip6_option_hdr {
 143 #define IP6_OPT_PAD1   (0x00)
 144 #define IP6_OPT_HOME   (0xC9)
 145     uint8_t type;
 146     uint8_t len;
 147 };
 148
 149 struct udp_hdr {
 150   uint16_t uh_sport;           /* source port */
 151   uint16_t uh_dport;           /* destination port */
 152   uint16_t uh_ulen;            /* udp length */
 153   uint16_t uh_sum;             /* udp checksum */
 154 };
 155
 156 struct tcp_hdr {
 157     u_short     th_sport;   /* source port */
 158     u_short     th_dport;   /* destination port */
 159     uint32_t    th_seq;     /* sequence number */
 160     uint32_t    th_ack;     /* acknowledgment number */
 161 #ifdef HOST_WORDS_BIGENDIAN
 162     u_char  th_off : 4,     /* data offset */
 163         th_x2:4;            /* (unused) */
 164 #else
 165     u_char  th_x2 : 4,      /* (unused) */
 166         th_off:4;           /* data offset */
 167 #endif
 168
 169 #define TH_ELN  0x1 /* explicit loss notification */
 170 #define TH_ECN  0x2 /* explicit congestion notification */
 171 #define TH_FS   0x4 /* fast start */
 172
 173     u_char  th_flags;
 174 #define TH_FIN  0x01
 175 #define TH_SYN  0x02
 176 #define TH_RST  0x04
 177 #define TH_PUSH 0x08
 178 #define TH_ACK  0x10
 179 #define TH_URG  0x20
 180     u_short th_win;      /* window */
 181     u_short th_sum;      /* checksum */
 182     u_short th_urp;      /* urgent pointer */
 183 };
 184
 185 #define ip6_nxt      ip6_ctlun.ip6_un1.ip6_un1_nxt
 186 #define ip6_ecn_acc  ip6_ctlun.ip6_un3.ip6_un3_ecn
 187
 188 #define PKT_GET_ETH_HDR(p)        \
 189     ((struct eth_header *)(p))
 190 #define PKT_GET_VLAN_HDR(p)       \
 191     ((struct vlan_header *) (((uint8_t *)(p)) + sizeof(struct eth_header)))
 192 #define PKT_GET_DVLAN_HDR(p)       \
 193     (PKT_GET_VLAN_HDR(p) + 1)
 194 #define PKT_GET_IP_HDR(p)         \
 195     ((struct ip_header *)(((uint8_t *)(p)) + eth_get_l2_hdr_length(p)))
 196 #define IP_HDR_GET_LEN(p)         \
 197     ((((struct ip_header *)(p))->ip_ver_len & 0x0F) << 2)
 198 #define PKT_GET_IP_HDR_LEN(p)     \
 199     (IP_HDR_GET_LEN(PKT_GET_IP_HDR(p)))
 200 #define PKT_GET_IP6_HDR(p)        \
 201     ((struct ip6_header *) (((uint8_t *)(p)) + eth_get_l2_hdr_length(p)))
 202 #define IP_HEADER_VERSION(ip)     \
 203     (((ip)->ip_ver_len >> 4) & 0xf)
 204 #define IP4_IS_FRAGMENT(ip) \
 205     ((be16_to_cpu((ip)->ip_off) & (IP_OFFMASK | IP_MF)) != 0)
 206
 207 #define ETH_P_IP                  (0x0800)      /* Internet Protocol packet  */
 208 #define ETH_P_ARP                 (0x0806)      /* Address Resolution packet */
 209 #define ETH_P_IPV6                (0x86dd)
 210 #define ETH_P_VLAN                (0x8100)
 211 #define ETH_P_DVLAN               (0x88a8)
 212 #define ETH_P_UNKNOWN             (0xffff)
 213 #define VLAN_VID_MASK             0x0fff
 214 #define IP_HEADER_VERSION_4       (4)
 215 #define IP_HEADER_VERSION_6       (6)
 216 #define IP_PROTO_TCP              (6)
 217 #define IP_PROTO_UDP              (17)
 218 #define IPTOS_ECN_MASK            0x03
 219 #define IPTOS_ECN(x)              ((x) & IPTOS_ECN_MASK)
 220 #define IPTOS_ECN_CE              0x03
 221 #define IP6_ECN_MASK              0xC0
 222 #define IP6_ECN(x)                ((x) & IP6_ECN_MASK)
 223 #define IP6_ECN_CE                0xC0
 224 #define IP4_DONT_FRAGMENT_FLAG    (1 << 14)
 225
 226 #define IS_SPECIAL_VLAN_ID(x)     \
 227     (((x) == 0) || ((x) == 0xFFF))
 228
 229 #define ETH_MAX_L2_HDR_LEN  \
 230     (sizeof(struct eth_header) + 2 * sizeof(struct vlan_header))
 231
 232 #define ETH_MAX_IP4_HDR_LEN   (60)
 233 #define ETH_MAX_IP_DGRAM_LEN  (0xFFFF)
 234
 235 #define IP_FRAG_UNIT_SIZE     (8)
 236 #define IP_FRAG_ALIGN_SIZE(x) ((x) & ~0x7)
 237 #define IP_RF                 0x8000           /* reserved fragment flag */
 238 #define IP_DF                 0x4000           /* don't fragment flag */
 239 #define IP_MF                 0x2000           /* more fragments flag */
 240 #define IP_OFFMASK            0x1fff           /* mask for fragmenting bits */
 241
 242 #define IP6_EXT_GRANULARITY   (8)  /* Size granularity for
 243                                       IPv6 extension headers */
 244
 245 /* IP6 extension header types */
 246 #define IP6_HOP_BY_HOP        (0)
 247 #define IP6_ROUTING           (43)
 248 #define IP6_FRAGMENT          (44)
 249 #define IP6_ESP               (50)
 250 #define IP6_AUTHENTICATION    (51)
 251 #define IP6_NONE              (59)
 252 #define IP6_DESTINATON        (60)
 253 #define IP6_MOBILITY          (135)
 254
 255 static inline int is_multicast_ether_addr(const uint8_t *addr)
 256 {
 257     return 0x01 & addr[0];
 258 }
 259
 260 static inline int is_broadcast_ether_addr(const uint8_t *addr)
 261 {
 262     return (addr[0] & addr[1] & addr[2] & addr[3] & addr[4] & addr[5]) == 0xff;
 263 }
 264
 265 static inline int is_unicast_ether_addr(const uint8_t *addr)
 266 {
 267     return !is_multicast_ether_addr(addr);
 268 }
 269
 270 typedef enum {
 271     ETH_PKT_UCAST = 0xAABBCC00,
 272     ETH_PKT_BCAST,
 273     ETH_PKT_MCAST
 274 } eth_pkt_types_e;
 275
 276 static inline eth_pkt_types_e
 277 get_eth_packet_type(const struct eth_header *ehdr)
 278 {
 279     if (is_broadcast_ether_addr(ehdr->h_dest)) {
 280         return ETH_PKT_BCAST;
 281     } else if (is_multicast_ether_addr(ehdr->h_dest)) {
 282         return ETH_PKT_MCAST;
 283     } else { /* unicast */
 284         return ETH_PKT_UCAST;
 285     }
 286 }
 287
 288 static inline uint32_t
 289 eth_get_l2_hdr_length(const void *p)
 290 {
 291     uint16_t proto = be16_to_cpu(PKT_GET_ETH_HDR(p)->h_proto);
 292     struct vlan_header *hvlan = PKT_GET_VLAN_HDR(p);
 293     switch (proto) {
 294     case ETH_P_VLAN:
 295         return sizeof(struct eth_header) + sizeof(struct vlan_header);
 296     case ETH_P_DVLAN:
 297         if (be16_to_cpu(hvlan->h_proto) == ETH_P_VLAN) {
 298             return sizeof(struct eth_header) + 2 * sizeof(struct vlan_header);
 299         } else {
 300             return sizeof(struct eth_header) + sizeof(struct vlan_header);
 301         }
 302     default:
 303         return sizeof(struct eth_header);
 304     }
 305 }
 306
 307 static inline uint32_t
 308 eth_get_l2_hdr_length_iov(const struct iovec *iov, int iovcnt)
 309 {
 310     uint8_t p[sizeof(struct eth_header) + sizeof(struct vlan_header)];
 311     size_t copied = iov_to_buf(iov, iovcnt, 0, p, ARRAY_SIZE(p));
 312
 313     if (copied < ARRAY_SIZE(p)) {
 314         return copied;
 315     }
 316
 317     return eth_get_l2_hdr_length(p);
 318 }
 319
 320 static inline uint16_t
 321 eth_get_pkt_tci(const void *p)
 322 {
 323     uint16_t proto = be16_to_cpu(PKT_GET_ETH_HDR(p)->h_proto);
 324     struct vlan_header *hvlan = PKT_GET_VLAN_HDR(p);
 325     switch (proto) {
 326     case ETH_P_VLAN:
 327     case ETH_P_DVLAN:
 328         return be16_to_cpu(hvlan->h_tci);
 329     default:
 330         return 0;
 331     }
 332 }
 333
 334 bool
 335 eth_strip_vlan(const struct iovec *iov, int iovcnt, size_t iovoff,
 336                uint8_t *new_ehdr_buf,
 337                uint16_t *payload_offset, uint16_t *tci);
 338
 339 bool
 340 eth_strip_vlan_ex(const struct iovec *iov, int iovcnt, size_t iovoff,
 341                   uint16_t vet, uint8_t *new_ehdr_buf,
 342                   uint16_t *payload_offset, uint16_t *tci);
 343
 344 uint16_t
 345 eth_get_l3_proto(const struct iovec *l2hdr_iov, int iovcnt, size_t l2hdr_len);
 346
 347 void eth_setup_vlan_headers_ex(struct eth_header *ehdr, uint16_t vlan_tag,
 348     uint16_t vlan_ethtype, bool *is_new);
 349
 350 static inline void
 351 eth_setup_vlan_headers(struct eth_header *ehdr, uint16_t vlan_tag,
 352     bool *is_new)
 353 {
 354     eth_setup_vlan_headers_ex(ehdr, vlan_tag, ETH_P_VLAN, is_new);
 355 }
 356
 357
 358 uint8_t eth_get_gso_type(uint16_t l3_proto, uint8_t *l3_hdr, uint8_t l4proto);
 359
 360 typedef struct eth_ip6_hdr_info_st {
 361     uint8_t l4proto;
 362     size_t  full_hdr_len;
 363     struct  ip6_header ip6_hdr;
 364     bool    has_ext_hdrs;
 365     bool    rss_ex_src_valid;
 366     struct  in6_address rss_ex_src;
 367     bool    rss_ex_dst_valid;
 368     struct  in6_address rss_ex_dst;
 369     bool    fragment;
 370 } eth_ip6_hdr_info;
 371
 372 typedef struct eth_ip4_hdr_info_st {
 373     struct ip_header ip4_hdr;
 374     bool   fragment;
 375 } eth_ip4_hdr_info;
 376
 377 typedef struct eth_l4_hdr_info_st {
 378     union {
 379         struct tcp_header tcp;
 380         struct udp_header udp;
 381     } hdr;
 382
 383     bool has_tcp_data;
 384 } eth_l4_hdr_info;
 385
 386 void eth_get_protocols(const struct iovec *iov, int iovcnt,
 387                        bool *isip4, bool *isip6,
 388                        bool *isudp, bool *istcp,
 389                        size_t *l3hdr_off,
 390                        size_t *l4hdr_off,
 391                        size_t *l5hdr_off,
 392                        eth_ip6_hdr_info *ip6hdr_info,
 393                        eth_ip4_hdr_info *ip4hdr_info,
 394                        eth_l4_hdr_info  *l4hdr_info);
 395
 396 void eth_setup_ip4_fragmentation(const void *l2hdr, size_t l2hdr_len,
 397                                  void *l3hdr, size_t l3hdr_len,
 398                                  size_t l3payload_len,
 399                                  size_t frag_offset, bool more_frags);
 400
 401 void
 402 eth_fix_ip4_checksum(void *l3hdr, size_t l3hdr_len);
 403
 404 uint32_t
 405 eth_calc_ip4_pseudo_hdr_csum(struct ip_header *iphdr,
 406                              uint16_t csl,
 407                              uint32_t *cso);
 408
 409 uint32_t
 410 eth_calc_ip6_pseudo_hdr_csum(struct ip6_header *iphdr,
 411                              uint16_t csl,
 412                              uint8_t l4_proto,
 413                              uint32_t *cso);
 414
 415 bool
 416 eth_parse_ipv6_hdr(const struct iovec *pkt, int pkt_frags,
 417                    size_t ip6hdr_off, eth_ip6_hdr_info *info);
 418
 419 #endif