xref: /openbmc/qemu/include/net/eth.h (revision 7d87775f)
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 } QEMU_PACKED;
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
441