xref: /openbmc/qemu/include/net/eth.h (revision 1b111dc1)
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 <sys/types.h>
30 #include <string.h>
31 #include "qemu/bswap.h"
32 #include "qemu/iov.h"
33 
34 #define ETH_ALEN 6
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 typedef struct udp_header {
72     uint16_t uh_sport; /* source port */
73     uint16_t uh_dport; /* destination port */
74     uint16_t uh_ulen;  /* udp length */
75     uint16_t uh_sum;   /* udp checksum */
76 } udp_header;
77 
78 typedef struct ip_pseudo_header {
79     uint32_t ip_src;
80     uint32_t ip_dst;
81     uint8_t  zeros;
82     uint8_t  ip_proto;
83     uint16_t ip_payload;
84 } ip_pseudo_header;
85 
86 /* IPv6 address */
87 struct in6_address {
88     union {
89         uint8_t __u6_addr8[16];
90     } __in6_u;
91 };
92 
93 struct ip6_header {
94     union {
95         struct ip6_hdrctl {
96             uint32_t ip6_un1_flow; /* 4 bits version, 8 bits TC,
97                                       20 bits flow-ID */
98             uint16_t ip6_un1_plen; /* payload length */
99             uint8_t  ip6_un1_nxt;  /* next header */
100             uint8_t  ip6_un1_hlim; /* hop limit */
101         } ip6_un1;
102         uint8_t ip6_un2_vfc;       /* 4 bits version, top 4 bits tclass */
103         struct ip6_ecn_access {
104             uint8_t  ip6_un3_vfc;  /* 4 bits version, top 4 bits tclass */
105             uint8_t  ip6_un3_ecn;  /* 2 bits ECN, top 6 bits payload length */
106         } ip6_un3;
107     } ip6_ctlun;
108     struct in6_address ip6_src;    /* source address */
109     struct in6_address ip6_dst;    /* destination address */
110 };
111 
112 struct ip6_ext_hdr {
113     uint8_t        ip6r_nxt;   /* next header */
114     uint8_t        ip6r_len;   /* length in units of 8 octets */
115 };
116 
117 struct udp_hdr {
118   uint16_t uh_sport;           /* source port */
119   uint16_t uh_dport;           /* destination port */
120   uint16_t uh_ulen;            /* udp length */
121   uint16_t uh_sum;             /* udp checksum */
122 };
123 
124 struct tcp_hdr {
125     u_short     th_sport;   /* source port */
126     u_short     th_dport;   /* destination port */
127     uint32_t    th_seq;     /* sequence number */
128     uint32_t    th_ack;     /* acknowledgment number */
129 #ifdef HOST_WORDS_BIGENDIAN
130     u_char  th_off : 4,     /* data offset */
131         th_x2:4;            /* (unused) */
132 #else
133     u_char  th_x2 : 4,      /* (unused) */
134         th_off:4;           /* data offset */
135 #endif
136 
137 #define TH_ELN  0x1 /* explicit loss notification */
138 #define TH_ECN  0x2 /* explicit congestion notification */
139 #define TH_FS   0x4 /* fast start */
140 
141     u_char  th_flags;
142 #define TH_FIN  0x01
143 #define TH_SYN  0x02
144 #define TH_RST  0x04
145 #define TH_PUSH 0x08
146 #define TH_ACK  0x10
147 #define TH_URG  0x20
148     u_short th_win;      /* window */
149     u_short th_sum;      /* checksum */
150     u_short th_urp;      /* urgent pointer */
151 };
152 
153 #define ip6_nxt      ip6_ctlun.ip6_un1.ip6_un1_nxt
154 #define ip6_ecn_acc  ip6_ctlun.ip6_un3.ip6_un3_ecn
155 
156 #define PKT_GET_ETH_HDR(p)        \
157     ((struct eth_header *)(p))
158 #define PKT_GET_VLAN_HDR(p)       \
159     ((struct vlan_header *) (((uint8_t *)(p)) + sizeof(struct eth_header)))
160 #define PKT_GET_DVLAN_HDR(p)       \
161     (PKT_GET_VLAN_HDR(p) + 1)
162 #define PKT_GET_IP_HDR(p)         \
163     ((struct ip_header *)(((uint8_t *)(p)) + eth_get_l2_hdr_length(p)))
164 #define IP_HDR_GET_LEN(p)         \
165     ((((struct ip_header *)p)->ip_ver_len & 0x0F) << 2)
166 #define PKT_GET_IP_HDR_LEN(p)     \
167     (IP_HDR_GET_LEN(PKT_GET_IP_HDR(p)))
168 #define PKT_GET_IP6_HDR(p)        \
169     ((struct ip6_header *) (((uint8_t *)(p)) + eth_get_l2_hdr_length(p)))
170 #define IP_HEADER_VERSION(ip)     \
171     ((ip->ip_ver_len >> 4)&0xf)
172 
173 #define ETH_P_IP                  (0x0800)
174 #define ETH_P_IPV6                (0x86dd)
175 #define ETH_P_VLAN                (0x8100)
176 #define ETH_P_DVLAN               (0x88a8)
177 #define VLAN_VID_MASK             0x0fff
178 #define IP_HEADER_VERSION_4       (4)
179 #define IP_HEADER_VERSION_6       (6)
180 #define IP_PROTO_TCP              (6)
181 #define IP_PROTO_UDP              (17)
182 #define IPTOS_ECN_MASK            0x03
183 #define IPTOS_ECN(x)              ((x) & IPTOS_ECN_MASK)
184 #define IPTOS_ECN_CE              0x03
185 #define IP6_ECN_MASK              0xC0
186 #define IP6_ECN(x)                ((x) & IP6_ECN_MASK)
187 #define IP6_ECN_CE                0xC0
188 #define IP4_DONT_FRAGMENT_FLAG    (1 << 14)
189 
190 #define IS_SPECIAL_VLAN_ID(x)     \
191     (((x) == 0) || ((x) == 0xFFF))
192 
193 #define ETH_MAX_L2_HDR_LEN  \
194     (sizeof(struct eth_header) + 2 * sizeof(struct vlan_header))
195 
196 #define ETH_MAX_IP4_HDR_LEN   (60)
197 #define ETH_MAX_IP_DGRAM_LEN  (0xFFFF)
198 
199 #define IP_FRAG_UNIT_SIZE     (8)
200 #define IP_FRAG_ALIGN_SIZE(x) ((x) & ~0x7)
201 #define IP_RF                 0x8000           /* reserved fragment flag */
202 #define IP_DF                 0x4000           /* don't fragment flag */
203 #define IP_MF                 0x2000           /* more fragments flag */
204 #define IP_OFFMASK            0x1fff           /* mask for fragmenting bits */
205 
206 #define IP6_EXT_GRANULARITY   (8)  /* Size granularity for
207                                       IPv6 extension headers */
208 
209 /* IP6 extension header types */
210 #define IP6_HOP_BY_HOP        (0)
211 #define IP6_ROUTING           (43)
212 #define IP6_FRAGMENT          (44)
213 #define IP6_ESP               (50)
214 #define IP6_AUTHENTICATION    (51)
215 #define IP6_NONE              (59)
216 #define IP6_DESTINATON        (60)
217 #define IP6_MOBILITY          (135)
218 
219 static inline int is_multicast_ether_addr(const uint8_t *addr)
220 {
221     return 0x01 & addr[0];
222 }
223 
224 static inline int is_broadcast_ether_addr(const uint8_t *addr)
225 {
226     return (addr[0] & addr[1] & addr[2] & addr[3] & addr[4] & addr[5]) == 0xff;
227 }
228 
229 static inline int is_unicast_ether_addr(const uint8_t *addr)
230 {
231     return !is_multicast_ether_addr(addr);
232 }
233 
234 typedef enum {
235     ETH_PKT_UCAST = 0xAABBCC00,
236     ETH_PKT_BCAST,
237     ETH_PKT_MCAST
238 } eth_pkt_types_e;
239 
240 static inline eth_pkt_types_e
241 get_eth_packet_type(const struct eth_header *ehdr)
242 {
243     if (is_broadcast_ether_addr(ehdr->h_dest)) {
244         return ETH_PKT_BCAST;
245     } else if (is_multicast_ether_addr(ehdr->h_dest)) {
246         return ETH_PKT_MCAST;
247     } else { /* unicast */
248         return ETH_PKT_UCAST;
249     }
250 }
251 
252 static inline uint32_t
253 eth_get_l2_hdr_length(const void *p)
254 {
255     uint16_t proto = be16_to_cpu(PKT_GET_ETH_HDR(p)->h_proto);
256     struct vlan_header *hvlan = PKT_GET_VLAN_HDR(p);
257     switch (proto) {
258     case ETH_P_VLAN:
259         return sizeof(struct eth_header) + sizeof(struct vlan_header);
260     case ETH_P_DVLAN:
261         if (hvlan->h_proto == ETH_P_VLAN) {
262             return sizeof(struct eth_header) + 2 * sizeof(struct vlan_header);
263         } else {
264             return sizeof(struct eth_header) + sizeof(struct vlan_header);
265         }
266     default:
267         return sizeof(struct eth_header);
268     }
269 }
270 
271 static inline uint16_t
272 eth_get_pkt_tci(const void *p)
273 {
274     uint16_t proto = be16_to_cpu(PKT_GET_ETH_HDR(p)->h_proto);
275     struct vlan_header *hvlan = PKT_GET_VLAN_HDR(p);
276     switch (proto) {
277     case ETH_P_VLAN:
278     case ETH_P_DVLAN:
279         return be16_to_cpu(hvlan->h_tci);
280     default:
281         return 0;
282     }
283 }
284 
285 static inline bool
286 eth_strip_vlan(const void *p, uint8_t *new_ehdr_buf,
287                uint16_t *payload_offset, uint16_t *tci)
288 {
289     uint16_t proto = be16_to_cpu(PKT_GET_ETH_HDR(p)->h_proto);
290     struct vlan_header *hvlan = PKT_GET_VLAN_HDR(p);
291     struct eth_header *new_ehdr = (struct eth_header *) new_ehdr_buf;
292 
293     switch (proto) {
294     case ETH_P_VLAN:
295     case ETH_P_DVLAN:
296         memcpy(new_ehdr->h_source, PKT_GET_ETH_HDR(p)->h_source, ETH_ALEN);
297         memcpy(new_ehdr->h_dest, PKT_GET_ETH_HDR(p)->h_dest, ETH_ALEN);
298         new_ehdr->h_proto = hvlan->h_proto;
299         *tci = be16_to_cpu(hvlan->h_tci);
300         *payload_offset =
301             sizeof(struct eth_header) + sizeof(struct vlan_header);
302         if (be16_to_cpu(new_ehdr->h_proto) == ETH_P_VLAN) {
303             memcpy(PKT_GET_VLAN_HDR(new_ehdr),
304                    PKT_GET_DVLAN_HDR(p),
305                    sizeof(struct vlan_header));
306             *payload_offset += sizeof(struct vlan_header);
307         }
308         return true;
309     default:
310         return false;
311     }
312 }
313 
314 static inline uint16_t
315 eth_get_l3_proto(const void *l2hdr, size_t l2hdr_len)
316 {
317     uint8_t *proto_ptr = (uint8_t *) l2hdr + l2hdr_len - sizeof(uint16_t);
318     return be16_to_cpup((uint16_t *)proto_ptr);
319 }
320 
321 void eth_setup_vlan_headers(struct eth_header *ehdr, uint16_t vlan_tag,
322     bool *is_new);
323 
324 uint8_t eth_get_gso_type(uint16_t l3_proto, uint8_t *l3_hdr, uint8_t l4proto);
325 
326 void eth_get_protocols(const uint8_t *headers,
327                        uint32_t hdr_length,
328                        bool *isip4, bool *isip6,
329                        bool *isudp, bool *istcp);
330 
331 void eth_setup_ip4_fragmentation(const void *l2hdr, size_t l2hdr_len,
332                                  void *l3hdr, size_t l3hdr_len,
333                                  size_t l3payload_len,
334                                  size_t frag_offset, bool more_frags);
335 
336 void
337 eth_fix_ip4_checksum(void *l3hdr, size_t l3hdr_len);
338 
339 uint32_t
340 eth_calc_pseudo_hdr_csum(struct ip_header *iphdr, uint16_t csl);
341 
342 bool
343 eth_parse_ipv6_hdr(struct iovec *pkt, int pkt_frags,
344                    size_t ip6hdr_off, uint8_t *l4proto,
345                    size_t *full_hdr_len);
346 
347 #endif
348