trafgen_l2.c

   1 /*
   2  * netsniff-ng - the packet sniffing beast
   3  * Subject to the GPL, version 2.
   4  */
   5
   6 #include <net/if_arp.h>
   7 #include <linux/if_ether.h>
   8
   9 #include "die.h"
  10 #include "built_in.h"
  11 #include "linktype.h"
  12 #include "trafgen_l2.h"
  13 #include "trafgen_dev.h"
  14 #include "trafgen_proto.h"
  15
  16 static struct proto_field eth_fields[] = {
  17         { .id = ETH_DST_ADDR, .len = 6, },
  18         { .id = ETH_SRC_ADDR, .len = 6, .offset = 6 },
  19         { .id = ETH_TYPE,     .len = 2, .offset = 12 },
  20 };
  21
  22 static uint16_t pid_to_eth(enum proto_id pid)
  23 {
  24         switch (pid) {
  25         case PROTO_ARP:
  26                 return ETH_P_ARP;
  27         case PROTO_IP4:
  28                 return ETH_P_IP;
  29         case PROTO_IP6:
  30                 return ETH_P_IPV6;
  31         case PROTO_MPLS:
  32                 return ETH_P_MPLS_UC;
  33         case PROTO_VLAN:
  34                 return ETH_P_8021Q;
  35         case PROTO_PAUSE:
  36         case PROTO_PFC:
  37                 return ETH_P_PAUSE;
  38         default:
  39                 bug();
  40         }
  41 }
  42
  43 static void eth_set_next_proto(struct proto_hdr *hdr, enum proto_id pid)
  44 {
  45         proto_hdr_field_set_default_be16(hdr, ETH_TYPE, pid_to_eth(pid));
  46 }
  47
  48 static void eth_header_init(struct proto_hdr *hdr)
  49 {
  50         proto_header_fields_add(hdr, eth_fields, array_size(eth_fields));
  51
  52         proto_hdr_field_set_default_dev_mac(hdr, ETH_SRC_ADDR);
  53
  54         dev_io_link_type_set(proto_dev_get(), LINKTYPE_EN10MB);
  55 }
  56
  57 static const struct proto_ops eth_proto_ops = {
  58         .id             = PROTO_ETH,
  59         .layer          = PROTO_L2,
  60         .header_init    = eth_header_init,
  61         .set_next_proto = eth_set_next_proto,
  62 };
  63
  64 static struct proto_field pause_fields[] = {
  65         { .id = PAUSE_OPCODE,   .len = 2, .offset = 0 },
  66         { .id = PAUSE_TIME,     .len = 2, .offset = 2 },
  67 };
  68
  69 static void pause_header_init(struct proto_hdr *hdr)
  70 {
  71         uint8_t eth_dst[6] = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x01 };
  72
  73         struct proto_hdr *lower;
  74
  75         lower = proto_lower_default_add(hdr, PROTO_ETH);
  76         proto_hdr_field_set_default_bytes(lower, ETH_DST_ADDR, eth_dst, 6);
  77
  78         proto_header_fields_add(hdr, pause_fields, array_size(pause_fields));
  79         proto_hdr_field_set_default_be16(hdr, PAUSE_OPCODE, 0x1);
  80 }
  81
  82 static struct proto_ops pause_proto_ops = {
  83         .id             = PROTO_PAUSE,
  84         .layer          = PROTO_L2,
  85         .header_init    = pause_header_init,
  86 };
  87
  88 static struct proto_field pfc_fields[] = {
  89         { .id = PFC_OPCODE,  .len = 2, .offset = 0 },
  90         { .id = PFC_PRIO,    .len = 2, .offset = 2 },
  91         { .id = PFC_PRIO_0,  .len = 2, .offset = 2, .mask = 0x0001 },
  92         { .id = PFC_PRIO_1,  .len = 2, .offset = 2, .mask = 0x0002, .shift = 1 },
  93         { .id = PFC_PRIO_2,  .len = 2, .offset = 2, .mask = 0x0004, .shift = 2 },
  94         { .id = PFC_PRIO_3,  .len = 2, .offset = 2, .mask = 0x0008, .shift = 3 },
  95         { .id = PFC_PRIO_4,  .len = 2, .offset = 2, .mask = 0x0010, .shift = 4 },
  96         { .id = PFC_PRIO_5,  .len = 2, .offset = 2, .mask = 0x0020, .shift = 5 },
  97         { .id = PFC_PRIO_6,  .len = 2, .offset = 2, .mask = 0x0040, .shift = 6 },
  98         { .id = PFC_PRIO_7,  .len = 2, .offset = 2, .mask = 0x0080, .shift = 7 },
  99         { .id = PFC_TIME_0,  .len = 2, .offset = 4,  },
 100         { .id = PFC_TIME_1,  .len = 2, .offset = 6,  },
 101         { .id = PFC_TIME_2,  .len = 2, .offset = 8,  },
 102         { .id = PFC_TIME_3,  .len = 2, .offset = 10, },
 103         { .id = PFC_TIME_4,  .len = 2, .offset = 12, },
 104         { .id = PFC_TIME_5,  .len = 2, .offset = 14, },
 105         { .id = PFC_TIME_6,  .len = 2, .offset = 16, },
 106         { .id = PFC_TIME_7,  .len = 2, .offset = 18, },
 107 };
 108
 109 static void pfc_header_init(struct proto_hdr *hdr)
 110 {
 111         uint8_t eth_dst[6] = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x01 };
 112
 113         struct proto_hdr *lower;
 114
 115         lower = proto_lower_default_add(hdr, PROTO_ETH);
 116         proto_hdr_field_set_default_bytes(lower, ETH_DST_ADDR, eth_dst, 6);
 117
 118         proto_header_fields_add(hdr, pfc_fields, array_size(pfc_fields));
 119         proto_hdr_field_set_default_be16(hdr, PFC_OPCODE, 0x0101);
 120 }
 121
 122 static struct proto_ops pfc_proto_ops = {
 123         .id             = PROTO_PFC,
 124         .layer          = PROTO_L2,
 125         .header_init    = pfc_header_init,
 126 };
 127
 128 static struct proto_field vlan_fields[] = {
 129         /* TPID overlaps with Ethernet header and points to ether type */
 130         { .id = VLAN_TPID, .len = 2, .offset = -2 },
 131         { .id = VLAN_TCI,  .len = 2, .offset = 0 },
 132         { .id = VLAN_PCP,  .len = 2, .offset = 0, .shift = 13, .mask = 0xe000 },
 133         { .id = VLAN_DEI,  .len = 2, .offset = 0, .shift = 12, .mask = 0x1000 },
 134         { .id = VLAN_VID,  .len = 2, .offset = 0, .shift = 0,  .mask = 0xfff },
 135         /* Original ether type is stored after VLAN header */
 136         { .id = VLAN_ETYPE, .len = 2, .offset = 2 },
 137 };
 138
 139 static void vlan_header_init(struct proto_hdr *hdr)
 140 {
 141         struct proto_hdr *lower = proto_lower_default_add(hdr, PROTO_ETH);
 142         uint16_t lower_etype = 0;
 143
 144         proto_header_fields_add(hdr, vlan_fields, array_size(vlan_fields));
 145
 146         if (lower->ops->id == PROTO_ETH)
 147                 lower_etype = proto_hdr_field_get_u16(lower, ETH_TYPE);
 148         else if (lower->ops->id == PROTO_VLAN)
 149                 lower_etype = proto_hdr_field_get_u16(lower, VLAN_ETYPE);
 150
 151         proto_hdr_field_set_be16(hdr, VLAN_ETYPE, lower_etype);
 152         proto_hdr_field_set_default_be16(hdr, VLAN_TPID, pid_to_eth(hdr->ops->id));
 153 }
 154
 155 static void vlan_set_next_proto(struct proto_hdr *hdr, enum proto_id pid)
 156 {
 157         if (pid != PROTO_VLAN)
 158                 proto_hdr_field_set_be16(hdr, VLAN_ETYPE, pid_to_eth(pid));
 159 }
 160
 161 static const struct proto_ops vlan_proto_ops = {
 162         .id             = PROTO_VLAN,
 163         .layer          = PROTO_L2,
 164         .header_init    = vlan_header_init,
 165         .set_next_proto = vlan_set_next_proto,
 166 };
 167
 168 static struct proto_field arp_fields[] = {
 169         { .id = ARP_HTYPE, .len = 2 },
 170         { .id = ARP_PTYPE, .len = 2, .offset = 2 },
 171         { .id = ARP_HLEN,  .len = 1, .offset = 4 },
 172         { .id = ARP_PLEN,  .len = 1, .offset = 5 },
 173         { .id = ARP_OPER,  .len = 2, .offset = 6 },
 174         { .id = ARP_SHA,   .len = 6, .offset = 8 },
 175         { .id = ARP_SPA,   .len = 4, .offset = 14 },
 176         { .id = ARP_THA,   .len = 6, .offset = 18 },
 177         { .id = ARP_TPA,   .len = 4, .offset = 24 },
 178 };
 179
 180 static void arp_header_init(struct proto_hdr *hdr)
 181 {
 182         struct proto_hdr *lower = proto_lower_default_add(hdr, PROTO_ETH);
 183
 184         if (lower->ops->id == PROTO_ETH) {
 185                 const uint8_t bcast[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
 186
 187                 proto_hdr_field_set_default_bytes(lower, ETH_DST_ADDR, bcast, 6);
 188         }
 189
 190         proto_header_fields_add(hdr, arp_fields, array_size(arp_fields));
 191
 192         /* Generate Announce request by default */
 193         proto_hdr_field_set_default_be16(hdr, ARP_HTYPE, ARPHRD_ETHER);
 194         proto_hdr_field_set_default_be16(hdr, ARP_PTYPE, ETH_P_IP);
 195         proto_hdr_field_set_default_u8(hdr, ARP_HLEN, 6);
 196         proto_hdr_field_set_default_u8(hdr, ARP_PLEN, 4);
 197         proto_hdr_field_set_default_be16(hdr, ARP_OPER, ARPOP_REQUEST);
 198         proto_hdr_field_set_default_dev_mac(hdr, ARP_SHA);
 199         proto_hdr_field_set_default_dev_ipv4(hdr, ARP_SPA);
 200         proto_hdr_field_set_default_dev_ipv4(hdr, ARP_TPA);
 201 }
 202
 203 static const struct proto_ops arp_proto_ops = {
 204         .id             = PROTO_ARP,
 205         .layer          = PROTO_L2,
 206         .header_init    = arp_header_init,
 207 };
 208
 209 static struct proto_field mpls_fields[] = {
 210         { .id = MPLS_LABEL, .len = 4, .shift = 12, .mask = 0xfffff000 },
 211         { .id = MPLS_TC,    .len = 4, .shift = 9,  .mask = 0xe00 },
 212         { .id = MPLS_LAST,  .len = 4, .shift = 8,  .mask = 0x100 },
 213         { .id = MPLS_TTL,   .len = 4, .shift = 0,  .mask = 0xff },
 214 };
 215
 216 static void mpls_header_init(struct proto_hdr *hdr)
 217 {
 218         proto_lower_default_add(hdr, PROTO_ETH);
 219
 220         proto_header_fields_add(hdr, mpls_fields, array_size(mpls_fields));
 221
 222         proto_hdr_field_set_default_be32(hdr, MPLS_LAST, 1);
 223 }
 224
 225 static void mpls_set_next_proto(struct proto_hdr *hdr, enum proto_id pid)
 226 {
 227         if (pid == PROTO_MPLS)
 228                 proto_hdr_field_set_default_be32(hdr, MPLS_LAST, 0);
 229 }
 230
 231 static const struct proto_ops mpls_proto_ops = {
 232         .id             = PROTO_MPLS,
 233         .layer          = PROTO_L2,
 234         .header_init    = mpls_header_init,
 235         .set_next_proto = mpls_set_next_proto,
 236 };
 237
 238 void protos_l2_init(void)
 239 {
 240         proto_ops_register(&eth_proto_ops);
 241         proto_ops_register(&pause_proto_ops);
 242         proto_ops_register(&pfc_proto_ops);
 243         proto_ops_register(&vlan_proto_ops);
 244         proto_ops_register(&arp_proto_ops);
 245         proto_ops_register(&mpls_proto_ops);
 246 }