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
  38 struct 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
  44 struct vlan_header {
  45     uint16_t  h_tci;     /* priority and VLAN ID  */
  46     uint16_t  h_proto;   /* encapsulated protocol */
  47 };
  48
  49 struct 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 };
  60
  61 typedef 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
  83 typedef 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
  90 typedef 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 */
  99 struct in6_address {
 100     union {
 101         uint8_t __u6_addr8[16];
 102     } __in6_u;
 103 };
 104
 105 struct 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
 124 typedef 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
 132 struct ip6_ext_hdr {
 133     uint8_t        ip6r_nxt;   /* next header */
 134     uint8_t        ip6r_len;   /* length in units of 8 octets */
 135 };
 136
 137 struct 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
 145 struct 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
 152 struct 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
 159 struct 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
 265 static inline int is_multicast_ether_addr(const uint8_t *addr)
 266 {
 267     return 0x01 & addr[0];
 268 }
 269
 270 static 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
 275 static inline int is_unicast_ether_addr(const uint8_t *addr)
 276 {
 277     return !is_multicast_ether_addr(addr);
 278 }
 279
 280 typedef enum {
 281     ETH_PKT_UCAST = 0xAABBCC00,
 282     ETH_PKT_BCAST,
 283     ETH_PKT_MCAST
 284 } eth_pkt_types_e;
 285
 286 static inline eth_pkt_types_e
 287 get_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
 298 static inline uint32_t
 299 eth_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
 317 static inline uint32_t
 318 eth_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
 330 static inline uint16_t
 331 eth_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
 344 size_t
 345 eth_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
 349 size_t
 350 eth_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
 354 uint16_t
 355 eth_get_l3_proto(const struct iovec *l2hdr_iov, int iovcnt, size_t l2hdr_len);
 356
 357 void eth_setup_vlan_headers(struct eth_header *ehdr, size_t *ehdr_size,
 358                             uint16_t vlan_tag, uint16_t vlan_ethtype);
 359
 360
 361 uint8_t eth_get_gso_type(uint16_t l3_proto, uint8_t *l3_hdr, uint8_t l4proto);
 362
 363 typedef 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
 375 typedef struct eth_ip4_hdr_info_st {
 376     struct ip_header ip4_hdr;
 377     bool   fragment;
 378 } eth_ip4_hdr_info;
 379
 380 typedef 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
 387 typedef 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
 397 void 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
 406 void
 407 eth_fix_ip4_checksum(void *l3hdr, size_t l3hdr_len);
 408
 409 uint32_t
 410 eth_calc_ip4_pseudo_hdr_csum(struct ip_header *iphdr,
 411                              uint16_t csl,
 412                              uint32_t *cso);
 413
 414 uint32_t
 415 eth_calc_ip6_pseudo_hdr_csum(struct ip6_header *iphdr,
 416                              uint16_t csl,
 417                              uint8_t l4_proto,
 418                              uint32_t *cso);
 419
 420 bool
 421 eth_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  */
 437 bool eth_pad_short_frame(uint8_t *padded_pkt, size_t *padded_buflen,
 438                          const void *pkt, size_t pkt_size);
 439
 440 #endif