xref: /openbmc/qemu/include/net/eth.h (revision 278f064e)
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 
36 struct eth_header {
37     uint8_t  h_dest[ETH_ALEN];   /* destination eth addr */
38     uint8_t  h_source[ETH_ALEN]; /* source ether addr    */
39     uint16_t h_proto;            /* packet type ID field */
40 };
41 
42 struct vlan_header {
43     uint16_t  h_tci;     /* priority and VLAN ID  */
44     uint16_t  h_proto;   /* encapsulated protocol */
45 };
46 
47 struct ip_header {
48     uint8_t  ip_ver_len;     /* version and header length */
49     uint8_t  ip_tos;         /* type of service */
50     uint16_t ip_len;         /* total length */
51     uint16_t ip_id;          /* identification */
52     uint16_t ip_off;         /* fragment offset field */
53     uint8_t  ip_ttl;         /* time to live */
54     uint8_t  ip_p;           /* protocol */
55     uint16_t ip_sum;         /* checksum */
56     uint32_t ip_src, ip_dst; /* source and destination address */
57 };
58 
59 typedef struct tcp_header {
60     uint16_t th_sport;          /* source port */
61     uint16_t th_dport;          /* destination port */
62     uint32_t th_seq;            /* sequence number */
63     uint32_t th_ack;            /* acknowledgment number */
64     uint16_t th_offset_flags;   /* data offset, reserved 6 bits, */
65                                 /* TCP protocol flags */
66     uint16_t th_win;            /* window */
67     uint16_t th_sum;            /* checksum */
68     uint16_t th_urp;            /* urgent pointer */
69 } tcp_header;
70 
71 #define TCP_FLAGS_ONLY(flags) ((flags) & 0x3f)
72 
73 #define TCP_HEADER_FLAGS(tcp) \
74     TCP_FLAGS_ONLY(be16_to_cpu((tcp)->th_offset_flags))
75 
76 #define TCP_FLAG_ACK  0x10
77 
78 #define TCP_HEADER_DATA_OFFSET(tcp) \
79     (((be16_to_cpu((tcp)->th_offset_flags) >> 12) & 0xf) << 2)
80 
81 typedef struct udp_header {
82     uint16_t uh_sport; /* source port */
83     uint16_t uh_dport; /* destination port */
84     uint16_t uh_ulen;  /* udp length */
85     uint16_t uh_sum;   /* udp checksum */
86 } udp_header;
87 
88 typedef struct ip_pseudo_header {
89     uint32_t ip_src;
90     uint32_t ip_dst;
91     uint8_t  zeros;
92     uint8_t  ip_proto;
93     uint16_t ip_payload;
94 } ip_pseudo_header;
95 
96 /* IPv6 address */
97 struct in6_address {
98     union {
99         uint8_t __u6_addr8[16];
100     } __in6_u;
101 };
102 
103 struct ip6_header {
104     union {
105         struct ip6_hdrctl {
106             uint32_t ip6_un1_flow; /* 4 bits version, 8 bits TC,
107                                       20 bits flow-ID */
108             uint16_t ip6_un1_plen; /* payload length */
109             uint8_t  ip6_un1_nxt;  /* next header */
110             uint8_t  ip6_un1_hlim; /* hop limit */
111         } ip6_un1;
112         uint8_t ip6_un2_vfc;       /* 4 bits version, top 4 bits tclass */
113         struct ip6_ecn_access {
114             uint8_t  ip6_un3_vfc;  /* 4 bits version, top 4 bits tclass */
115             uint8_t  ip6_un3_ecn;  /* 2 bits ECN, top 6 bits payload length */
116         } ip6_un3;
117     } ip6_ctlun;
118     struct in6_address ip6_src;    /* source address */
119     struct in6_address ip6_dst;    /* destination address */
120 };
121 
122 typedef struct ip6_pseudo_header {
123     struct in6_address ip6_src;
124     struct in6_address ip6_dst;
125     uint32_t           len;
126     uint8_t            zero[3];
127     uint8_t            next_hdr;
128 } ip6_pseudo_header;
129 
130 struct ip6_ext_hdr {
131     uint8_t        ip6r_nxt;   /* next header */
132     uint8_t        ip6r_len;   /* length in units of 8 octets */
133 };
134 
135 struct ip6_ext_hdr_routing {
136     uint8_t     nxt;
137     uint8_t     len;
138     uint8_t     rtype;
139     uint8_t     segleft;
140     uint8_t     rsvd[4];
141 };
142 
143 struct ip6_option_hdr {
144 #define IP6_OPT_PAD1   (0x00)
145 #define IP6_OPT_HOME   (0xC9)
146     uint8_t type;
147     uint8_t len;
148 };
149 
150 struct udp_hdr {
151   uint16_t uh_sport;           /* source port */
152   uint16_t uh_dport;           /* destination port */
153   uint16_t uh_ulen;            /* udp length */
154   uint16_t uh_sum;             /* udp checksum */
155 };
156 
157 struct tcp_hdr {
158     u_short     th_sport;   /* source port */
159     u_short     th_dport;   /* destination port */
160     uint32_t    th_seq;     /* sequence number */
161     uint32_t    th_ack;     /* acknowledgment number */
162 #ifdef HOST_WORDS_BIGENDIAN
163     u_char  th_off : 4,     /* data offset */
164         th_x2:4;            /* (unused) */
165 #else
166     u_char  th_x2 : 4,      /* (unused) */
167         th_off:4;           /* data offset */
168 #endif
169 
170 #define TH_ELN  0x1 /* explicit loss notification */
171 #define TH_ECN  0x2 /* explicit congestion notification */
172 #define TH_FS   0x4 /* fast start */
173 
174     u_char  th_flags;
175 #define TH_FIN  0x01
176 #define TH_SYN  0x02
177 #define TH_RST  0x04
178 #define TH_PUSH 0x08
179 #define TH_ACK  0x10
180 #define TH_URG  0x20
181 #define TH_ECE  0x40
182 #define TH_CWR  0x80
183     u_short th_win;      /* window */
184     u_short th_sum;      /* checksum */
185     u_short th_urp;      /* urgent pointer */
186 };
187 
188 #define ip6_nxt      ip6_ctlun.ip6_un1.ip6_un1_nxt
189 #define ip6_ecn_acc  ip6_ctlun.ip6_un3.ip6_un3_ecn
190 #define ip6_plen     ip6_ctlun.ip6_un1.ip6_un1_plen
191 
192 #define PKT_GET_ETH_HDR(p)        \
193     ((struct eth_header *)(p))
194 #define PKT_GET_VLAN_HDR(p)       \
195     ((struct vlan_header *) (((uint8_t *)(p)) + sizeof(struct eth_header)))
196 #define PKT_GET_DVLAN_HDR(p)       \
197     (PKT_GET_VLAN_HDR(p) + 1)
198 #define PKT_GET_IP_HDR(p)         \
199     ((struct ip_header *)(((uint8_t *)(p)) + eth_get_l2_hdr_length(p)))
200 #define IP_HDR_GET_LEN(p)         \
201     ((ldub_p(p + offsetof(struct ip_header, ip_ver_len)) & 0x0F) << 2)
202 #define IP_HDR_GET_P(p)                                           \
203     (ldub_p(p + offsetof(struct ip_header, ip_p)))
204 #define PKT_GET_IP_HDR_LEN(p)     \
205     (IP_HDR_GET_LEN(PKT_GET_IP_HDR(p)))
206 #define PKT_GET_IP6_HDR(p)        \
207     ((struct ip6_header *) (((uint8_t *)(p)) + eth_get_l2_hdr_length(p)))
208 #define IP_HEADER_VERSION(ip)     \
209     (((ip)->ip_ver_len >> 4) & 0xf)
210 #define IP4_IS_FRAGMENT(ip) \
211     ((be16_to_cpu((ip)->ip_off) & (IP_OFFMASK | IP_MF)) != 0)
212 
213 #define ETH_P_IP                  (0x0800)      /* Internet Protocol packet  */
214 #define ETH_P_ARP                 (0x0806)      /* Address Resolution packet */
215 #define ETH_P_IPV6                (0x86dd)
216 #define ETH_P_VLAN                (0x8100)
217 #define ETH_P_DVLAN               (0x88a8)
218 #define ETH_P_NCSI                (0x88f8)
219 #define ETH_P_UNKNOWN             (0xffff)
220 #define VLAN_VID_MASK             0x0fff
221 #define IP_HEADER_VERSION_4       (4)
222 #define IP_HEADER_VERSION_6       (6)
223 #define IP_PROTO_TCP              (6)
224 #define IP_PROTO_UDP              (17)
225 #define IPTOS_ECN_MASK            0x03
226 #define IPTOS_ECN(x)              ((x) & IPTOS_ECN_MASK)
227 #define IPTOS_ECN_CE              0x03
228 #define IP6_ECN_MASK              0xC0
229 #define IP6_ECN(x)                ((x) & IP6_ECN_MASK)
230 #define IP6_ECN_CE                0xC0
231 #define IP4_DONT_FRAGMENT_FLAG    (1 << 14)
232 
233 #define IS_SPECIAL_VLAN_ID(x)     \
234     (((x) == 0) || ((x) == 0xFFF))
235 
236 #define ETH_MAX_L2_HDR_LEN  \
237     (sizeof(struct eth_header) + 2 * sizeof(struct vlan_header))
238 
239 #define ETH_MAX_IP4_HDR_LEN   (60)
240 #define ETH_MAX_IP_DGRAM_LEN  (0xFFFF)
241 
242 #define IP_FRAG_UNIT_SIZE     (8)
243 #define IP_FRAG_ALIGN_SIZE(x) ((x) & ~0x7)
244 #define IP_RF                 0x8000           /* reserved fragment flag */
245 #define IP_DF                 0x4000           /* don't fragment flag */
246 #define IP_MF                 0x2000           /* more fragments flag */
247 #define IP_OFFMASK            0x1fff           /* mask for fragmenting bits */
248 
249 #define IP6_EXT_GRANULARITY   (8)  /* Size granularity for
250                                       IPv6 extension headers */
251 
252 /* IP6 extension header types */
253 #define IP6_HOP_BY_HOP        (0)
254 #define IP6_ROUTING           (43)
255 #define IP6_FRAGMENT          (44)
256 #define IP6_ESP               (50)
257 #define IP6_AUTHENTICATION    (51)
258 #define IP6_NONE              (59)
259 #define IP6_DESTINATON        (60)
260 #define IP6_MOBILITY          (135)
261 
262 static inline int is_multicast_ether_addr(const uint8_t *addr)
263 {
264     return 0x01 & addr[0];
265 }
266 
267 static inline int is_broadcast_ether_addr(const uint8_t *addr)
268 {
269     return (addr[0] & addr[1] & addr[2] & addr[3] & addr[4] & addr[5]) == 0xff;
270 }
271 
272 static inline int is_unicast_ether_addr(const uint8_t *addr)
273 {
274     return !is_multicast_ether_addr(addr);
275 }
276 
277 typedef enum {
278     ETH_PKT_UCAST = 0xAABBCC00,
279     ETH_PKT_BCAST,
280     ETH_PKT_MCAST
281 } eth_pkt_types_e;
282 
283 static inline eth_pkt_types_e
284 get_eth_packet_type(const struct eth_header *ehdr)
285 {
286     if (is_broadcast_ether_addr(ehdr->h_dest)) {
287         return ETH_PKT_BCAST;
288     } else if (is_multicast_ether_addr(ehdr->h_dest)) {
289         return ETH_PKT_MCAST;
290     } else { /* unicast */
291         return ETH_PKT_UCAST;
292     }
293 }
294 
295 static inline uint32_t
296 eth_get_l2_hdr_length(const void *p)
297 {
298     uint16_t proto = be16_to_cpu(PKT_GET_ETH_HDR(p)->h_proto);
299     struct vlan_header *hvlan = PKT_GET_VLAN_HDR(p);
300     switch (proto) {
301     case ETH_P_VLAN:
302         return sizeof(struct eth_header) + sizeof(struct vlan_header);
303     case ETH_P_DVLAN:
304         if (be16_to_cpu(hvlan->h_proto) == ETH_P_VLAN) {
305             return sizeof(struct eth_header) + 2 * sizeof(struct vlan_header);
306         } else {
307             return sizeof(struct eth_header) + sizeof(struct vlan_header);
308         }
309     default:
310         return sizeof(struct eth_header);
311     }
312 }
313 
314 static inline uint32_t
315 eth_get_l2_hdr_length_iov(const struct iovec *iov, int iovcnt)
316 {
317     uint8_t p[sizeof(struct eth_header) + sizeof(struct vlan_header)];
318     size_t copied = iov_to_buf(iov, iovcnt, 0, p, ARRAY_SIZE(p));
319 
320     if (copied < ARRAY_SIZE(p)) {
321         return copied;
322     }
323 
324     return eth_get_l2_hdr_length(p);
325 }
326 
327 static inline uint16_t
328 eth_get_pkt_tci(const void *p)
329 {
330     uint16_t proto = be16_to_cpu(PKT_GET_ETH_HDR(p)->h_proto);
331     struct vlan_header *hvlan = PKT_GET_VLAN_HDR(p);
332     switch (proto) {
333     case ETH_P_VLAN:
334     case ETH_P_DVLAN:
335         return be16_to_cpu(hvlan->h_tci);
336     default:
337         return 0;
338     }
339 }
340 
341 size_t
342 eth_strip_vlan(const struct iovec *iov, int iovcnt, size_t iovoff,
343                uint8_t *new_ehdr_buf,
344                uint16_t *payload_offset, uint16_t *tci);
345 
346 size_t
347 eth_strip_vlan_ex(const struct iovec *iov, int iovcnt, size_t iovoff,
348                   uint16_t vet, uint8_t *new_ehdr_buf,
349                   uint16_t *payload_offset, uint16_t *tci);
350 
351 uint16_t
352 eth_get_l3_proto(const struct iovec *l2hdr_iov, int iovcnt, size_t l2hdr_len);
353 
354 void eth_setup_vlan_headers_ex(struct eth_header *ehdr, uint16_t vlan_tag,
355     uint16_t vlan_ethtype, bool *is_new);
356 
357 static inline void
358 eth_setup_vlan_headers(struct eth_header *ehdr, uint16_t vlan_tag,
359     bool *is_new)
360 {
361     eth_setup_vlan_headers_ex(ehdr, vlan_tag, ETH_P_VLAN, is_new);
362 }
363 
364 
365 uint8_t eth_get_gso_type(uint16_t l3_proto, uint8_t *l3_hdr, uint8_t l4proto);
366 
367 typedef struct eth_ip6_hdr_info_st {
368     uint8_t l4proto;
369     size_t  full_hdr_len;
370     struct  ip6_header ip6_hdr;
371     bool    has_ext_hdrs;
372     bool    rss_ex_src_valid;
373     struct  in6_address rss_ex_src;
374     bool    rss_ex_dst_valid;
375     struct  in6_address rss_ex_dst;
376     bool    fragment;
377 } eth_ip6_hdr_info;
378 
379 typedef struct eth_ip4_hdr_info_st {
380     struct ip_header ip4_hdr;
381     bool   fragment;
382 } eth_ip4_hdr_info;
383 
384 typedef struct eth_l4_hdr_info_st {
385     union {
386         struct tcp_header tcp;
387         struct udp_header udp;
388     } hdr;
389 
390     bool has_tcp_data;
391 } eth_l4_hdr_info;
392 
393 void eth_get_protocols(const struct iovec *iov, int iovcnt,
394                        bool *isip4, bool *isip6,
395                        bool *isudp, bool *istcp,
396                        size_t *l3hdr_off,
397                        size_t *l4hdr_off,
398                        size_t *l5hdr_off,
399                        eth_ip6_hdr_info *ip6hdr_info,
400                        eth_ip4_hdr_info *ip4hdr_info,
401                        eth_l4_hdr_info  *l4hdr_info);
402 
403 void eth_setup_ip4_fragmentation(const void *l2hdr, size_t l2hdr_len,
404                                  void *l3hdr, size_t l3hdr_len,
405                                  size_t l3payload_len,
406                                  size_t frag_offset, bool more_frags);
407 
408 void
409 eth_fix_ip4_checksum(void *l3hdr, size_t l3hdr_len);
410 
411 uint32_t
412 eth_calc_ip4_pseudo_hdr_csum(struct ip_header *iphdr,
413                              uint16_t csl,
414                              uint32_t *cso);
415 
416 uint32_t
417 eth_calc_ip6_pseudo_hdr_csum(struct ip6_header *iphdr,
418                              uint16_t csl,
419                              uint8_t l4_proto,
420                              uint32_t *cso);
421 
422 bool
423 eth_parse_ipv6_hdr(const struct iovec *pkt, int pkt_frags,
424                    size_t ip6hdr_off, eth_ip6_hdr_info *info);
425 
426 /**
427  * eth_pad_short_frame - pad a short frame to the minimum Ethernet frame length
428  *
429  * If the Ethernet frame size is shorter than 60 bytes, it will be padded to
430  * 60 bytes at the address @padded_pkt.
431  *
432  * @padded_pkt: buffer address to hold the padded frame
433  * @padded_buflen: pointer holding length of @padded_pkt. If the frame is
434  *                 padded, the length will be updated to the padded one.
435  * @pkt: address to hold the original Ethernet frame
436  * @pkt_size: size of the original Ethernet frame
437  * @return true if the frame is padded, otherwise false
438  */
439 bool eth_pad_short_frame(uint8_t *padded_pkt, size_t *padded_buflen,
440                          const void *pkt, size_t pkt_size);
441 
442 #endif
443