Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 1 | /* This program is free software; you can redistribute it and/or modify |
| 2 | * it under the terms of the GNU General Public License version 2 |
| 3 | * as published by the Free Software Foundation. |
| 4 | * |
| 5 | * This program is distributed in the hope that it will be useful, |
| 6 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 7 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 8 | * GNU General Public License for more details. |
| 9 | */ |
| 10 | |
| 11 | #include <net/6lowpan.h> |
| 12 | #include <net/ieee802154_netdev.h> |
Alexander Aring | 87a93e4 | 2015-09-18 11:30:43 +0200 | [diff] [blame] | 13 | #include <net/mac802154.h> |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 14 | |
| 15 | #include "6lowpan_i.h" |
| 16 | |
Alexander Aring | 6350047 | 2015-10-20 08:31:22 +0200 | [diff] [blame] | 17 | #define LOWPAN_FRAG1_HEAD_SIZE 0x4 |
| 18 | #define LOWPAN_FRAGN_HEAD_SIZE 0x5 |
| 19 | |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 20 | /* don't save pan id, it's intra pan */ |
| 21 | struct lowpan_addr { |
| 22 | u8 mode; |
| 23 | union { |
| 24 | /* IPv6 needs big endian here */ |
| 25 | __be64 extended_addr; |
| 26 | __be16 short_addr; |
| 27 | } u; |
| 28 | }; |
| 29 | |
| 30 | struct lowpan_addr_info { |
| 31 | struct lowpan_addr daddr; |
| 32 | struct lowpan_addr saddr; |
| 33 | }; |
| 34 | |
| 35 | static inline struct |
| 36 | lowpan_addr_info *lowpan_skb_priv(const struct sk_buff *skb) |
| 37 | { |
| 38 | WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct lowpan_addr_info)); |
| 39 | return (struct lowpan_addr_info *)(skb->data - |
| 40 | sizeof(struct lowpan_addr_info)); |
| 41 | } |
| 42 | |
Alexander Aring | 87a93e4 | 2015-09-18 11:30:43 +0200 | [diff] [blame] | 43 | /* This callback will be called from AF_PACKET and IPv6 stack, the AF_PACKET |
| 44 | * sockets gives an 8 byte array for addresses only! |
| 45 | * |
| 46 | * TODO I think AF_PACKET DGRAM (sending/receiving) RAW (sending) makes no |
| 47 | * sense here. We should disable it, the right use-case would be AF_INET6 |
| 48 | * RAW/DGRAM sockets. |
| 49 | */ |
Alexander Aring | f460658 | 2015-09-02 14:21:16 +0200 | [diff] [blame] | 50 | int lowpan_header_create(struct sk_buff *skb, struct net_device *ldev, |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 51 | unsigned short type, const void *_daddr, |
| 52 | const void *_saddr, unsigned int len) |
| 53 | { |
| 54 | const u8 *saddr = _saddr; |
| 55 | const u8 *daddr = _daddr; |
| 56 | struct lowpan_addr_info *info; |
| 57 | |
| 58 | /* TODO: |
| 59 | * if this package isn't ipv6 one, where should it be routed? |
| 60 | */ |
| 61 | if (type != ETH_P_IPV6) |
| 62 | return 0; |
| 63 | |
| 64 | if (!saddr) |
Alexander Aring | f460658 | 2015-09-02 14:21:16 +0200 | [diff] [blame] | 65 | saddr = ldev->dev_addr; |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 66 | |
| 67 | raw_dump_inline(__func__, "saddr", (unsigned char *)saddr, 8); |
| 68 | raw_dump_inline(__func__, "daddr", (unsigned char *)daddr, 8); |
| 69 | |
| 70 | info = lowpan_skb_priv(skb); |
| 71 | |
| 72 | /* TODO: Currently we only support extended_addr */ |
| 73 | info->daddr.mode = IEEE802154_ADDR_LONG; |
| 74 | memcpy(&info->daddr.u.extended_addr, daddr, |
| 75 | sizeof(info->daddr.u.extended_addr)); |
| 76 | info->saddr.mode = IEEE802154_ADDR_LONG; |
| 77 | memcpy(&info->saddr.u.extended_addr, saddr, |
| 78 | sizeof(info->daddr.u.extended_addr)); |
| 79 | |
| 80 | return 0; |
| 81 | } |
| 82 | |
| 83 | static struct sk_buff* |
| 84 | lowpan_alloc_frag(struct sk_buff *skb, int size, |
Alexander Aring | 4bc8fbc | 2015-09-30 10:20:10 +0200 | [diff] [blame] | 85 | const struct ieee802154_hdr *master_hdr, bool frag1) |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 86 | { |
Alexander Aring | f460658 | 2015-09-02 14:21:16 +0200 | [diff] [blame] | 87 | struct net_device *wdev = lowpan_dev_info(skb->dev)->wdev; |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 88 | struct sk_buff *frag; |
| 89 | int rc; |
| 90 | |
Alexander Aring | 87a93e4 | 2015-09-18 11:30:43 +0200 | [diff] [blame] | 91 | frag = alloc_skb(wdev->needed_headroom + wdev->needed_tailroom + size, |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 92 | GFP_ATOMIC); |
| 93 | |
| 94 | if (likely(frag)) { |
Alexander Aring | f460658 | 2015-09-02 14:21:16 +0200 | [diff] [blame] | 95 | frag->dev = wdev; |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 96 | frag->priority = skb->priority; |
Alexander Aring | 87a93e4 | 2015-09-18 11:30:43 +0200 | [diff] [blame] | 97 | skb_reserve(frag, wdev->needed_headroom); |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 98 | skb_reset_network_header(frag); |
| 99 | *mac_cb(frag) = *mac_cb(skb); |
| 100 | |
Alexander Aring | 4bc8fbc | 2015-09-30 10:20:10 +0200 | [diff] [blame] | 101 | if (frag1) { |
| 102 | memcpy(skb_put(frag, skb->mac_len), |
| 103 | skb_mac_header(skb), skb->mac_len); |
| 104 | } else { |
| 105 | rc = wpan_dev_hard_header(frag, wdev, |
| 106 | &master_hdr->dest, |
| 107 | &master_hdr->source, size); |
| 108 | if (rc < 0) { |
| 109 | kfree_skb(frag); |
| 110 | return ERR_PTR(rc); |
| 111 | } |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 112 | } |
| 113 | } else { |
| 114 | frag = ERR_PTR(-ENOMEM); |
| 115 | } |
| 116 | |
| 117 | return frag; |
| 118 | } |
| 119 | |
| 120 | static int |
| 121 | lowpan_xmit_fragment(struct sk_buff *skb, const struct ieee802154_hdr *wpan_hdr, |
| 122 | u8 *frag_hdr, int frag_hdrlen, |
Alexander Aring | 4bc8fbc | 2015-09-30 10:20:10 +0200 | [diff] [blame] | 123 | int offset, int len, bool frag1) |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 124 | { |
| 125 | struct sk_buff *frag; |
| 126 | |
| 127 | raw_dump_inline(__func__, " fragment header", frag_hdr, frag_hdrlen); |
| 128 | |
Alexander Aring | 4bc8fbc | 2015-09-30 10:20:10 +0200 | [diff] [blame] | 129 | frag = lowpan_alloc_frag(skb, frag_hdrlen + len, wpan_hdr, frag1); |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 130 | if (IS_ERR(frag)) |
Alexander Aring | 8f8db91 | 2015-08-10 21:15:59 +0200 | [diff] [blame] | 131 | return PTR_ERR(frag); |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 132 | |
| 133 | memcpy(skb_put(frag, frag_hdrlen), frag_hdr, frag_hdrlen); |
| 134 | memcpy(skb_put(frag, len), skb_network_header(skb) + offset, len); |
| 135 | |
| 136 | raw_dump_table(__func__, " fragment dump", frag->data, frag->len); |
| 137 | |
| 138 | return dev_queue_xmit(frag); |
| 139 | } |
| 140 | |
| 141 | static int |
Alexander Aring | f460658 | 2015-09-02 14:21:16 +0200 | [diff] [blame] | 142 | lowpan_xmit_fragmented(struct sk_buff *skb, struct net_device *ldev, |
Alexander Aring | 5f50923 | 2015-10-01 08:03:06 +0200 | [diff] [blame] | 143 | const struct ieee802154_hdr *wpan_hdr, u16 dgram_size, |
| 144 | u16 dgram_offset) |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 145 | { |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 146 | __be16 frag_tag; |
| 147 | u8 frag_hdr[5]; |
| 148 | int frag_cap, frag_len, payload_cap, rc; |
| 149 | int skb_unprocessed, skb_offset; |
| 150 | |
Alexander Aring | f460658 | 2015-09-02 14:21:16 +0200 | [diff] [blame] | 151 | frag_tag = htons(lowpan_dev_info(ldev)->fragment_tag); |
| 152 | lowpan_dev_info(ldev)->fragment_tag++; |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 153 | |
| 154 | frag_hdr[0] = LOWPAN_DISPATCH_FRAG1 | ((dgram_size >> 8) & 0x07); |
| 155 | frag_hdr[1] = dgram_size & 0xff; |
| 156 | memcpy(frag_hdr + 2, &frag_tag, sizeof(frag_tag)); |
| 157 | |
| 158 | payload_cap = ieee802154_max_payload(wpan_hdr); |
| 159 | |
| 160 | frag_len = round_down(payload_cap - LOWPAN_FRAG1_HEAD_SIZE - |
| 161 | skb_network_header_len(skb), 8); |
| 162 | |
| 163 | skb_offset = skb_network_header_len(skb); |
| 164 | skb_unprocessed = skb->len - skb->mac_len - skb_offset; |
| 165 | |
| 166 | rc = lowpan_xmit_fragment(skb, wpan_hdr, frag_hdr, |
| 167 | LOWPAN_FRAG1_HEAD_SIZE, 0, |
Alexander Aring | 4bc8fbc | 2015-09-30 10:20:10 +0200 | [diff] [blame] | 168 | frag_len + skb_network_header_len(skb), |
| 169 | true); |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 170 | if (rc) { |
| 171 | pr_debug("%s unable to send FRAG1 packet (tag: %d)", |
| 172 | __func__, ntohs(frag_tag)); |
| 173 | goto err; |
| 174 | } |
| 175 | |
| 176 | frag_hdr[0] &= ~LOWPAN_DISPATCH_FRAG1; |
| 177 | frag_hdr[0] |= LOWPAN_DISPATCH_FRAGN; |
| 178 | frag_cap = round_down(payload_cap - LOWPAN_FRAGN_HEAD_SIZE, 8); |
| 179 | |
| 180 | do { |
| 181 | dgram_offset += frag_len; |
| 182 | skb_offset += frag_len; |
| 183 | skb_unprocessed -= frag_len; |
| 184 | frag_len = min(frag_cap, skb_unprocessed); |
| 185 | |
| 186 | frag_hdr[4] = dgram_offset >> 3; |
| 187 | |
| 188 | rc = lowpan_xmit_fragment(skb, wpan_hdr, frag_hdr, |
| 189 | LOWPAN_FRAGN_HEAD_SIZE, skb_offset, |
Alexander Aring | 4bc8fbc | 2015-09-30 10:20:10 +0200 | [diff] [blame] | 190 | frag_len, false); |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 191 | if (rc) { |
| 192 | pr_debug("%s unable to send a FRAGN packet. (tag: %d, offset: %d)\n", |
| 193 | __func__, ntohs(frag_tag), skb_offset); |
| 194 | goto err; |
| 195 | } |
| 196 | } while (skb_unprocessed > frag_cap); |
| 197 | |
Alexander Aring | 1c64f14 | 2015-09-30 10:20:11 +0200 | [diff] [blame] | 198 | ldev->stats.tx_packets++; |
| 199 | ldev->stats.tx_bytes += dgram_size; |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 200 | consume_skb(skb); |
| 201 | return NET_XMIT_SUCCESS; |
| 202 | |
| 203 | err: |
| 204 | kfree_skb(skb); |
| 205 | return rc; |
| 206 | } |
| 207 | |
Alexander Aring | 187625e | 2015-09-02 14:21:31 +0200 | [diff] [blame] | 208 | static int lowpan_header(struct sk_buff *skb, struct net_device *ldev, |
Alexander Aring | 5f50923 | 2015-10-01 08:03:06 +0200 | [diff] [blame] | 209 | u16 *dgram_size, u16 *dgram_offset) |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 210 | { |
Alexander Aring | f460658 | 2015-09-02 14:21:16 +0200 | [diff] [blame] | 211 | struct wpan_dev *wpan_dev = lowpan_dev_info(ldev)->wdev->ieee802154_ptr; |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 212 | struct ieee802154_addr sa, da; |
| 213 | struct ieee802154_mac_cb *cb = mac_cb_init(skb); |
| 214 | struct lowpan_addr_info info; |
| 215 | void *daddr, *saddr; |
| 216 | |
| 217 | memcpy(&info, lowpan_skb_priv(skb), sizeof(info)); |
| 218 | |
| 219 | /* TODO: Currently we only support extended_addr */ |
| 220 | daddr = &info.daddr.u.extended_addr; |
| 221 | saddr = &info.saddr.u.extended_addr; |
| 222 | |
Alexander Aring | 187625e | 2015-09-02 14:21:31 +0200 | [diff] [blame] | 223 | *dgram_size = skb->len; |
Alexander Aring | a6f7738 | 2015-10-13 13:42:57 +0200 | [diff] [blame] | 224 | lowpan_header_compress(skb, ldev, daddr, saddr); |
Alexander Aring | 187625e | 2015-09-02 14:21:31 +0200 | [diff] [blame] | 225 | /* dgram_offset = (saved bytes after compression) + lowpan header len */ |
| 226 | *dgram_offset = (*dgram_size - skb->len) + skb_network_header_len(skb); |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 227 | |
| 228 | cb->type = IEEE802154_FC_TYPE_DATA; |
| 229 | |
| 230 | /* prepare wpan address data */ |
| 231 | sa.mode = IEEE802154_ADDR_LONG; |
Alexander Aring | 1caf6f4 | 2015-06-02 15:55:17 +0200 | [diff] [blame] | 232 | sa.pan_id = wpan_dev->pan_id; |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 233 | sa.extended_addr = ieee802154_devaddr_from_raw(saddr); |
| 234 | |
| 235 | /* intra-PAN communications */ |
| 236 | da.pan_id = sa.pan_id; |
| 237 | |
| 238 | /* if the destination address is the broadcast address, use the |
| 239 | * corresponding short address |
| 240 | */ |
Alexander Aring | 028b2a8 | 2015-10-20 08:31:23 +0200 | [diff] [blame] | 241 | if (!memcmp(daddr, ldev->broadcast, EUI64_ADDR_LEN)) { |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 242 | da.mode = IEEE802154_ADDR_SHORT; |
| 243 | da.short_addr = cpu_to_le16(IEEE802154_ADDR_BROADCAST); |
| 244 | cb->ackreq = false; |
| 245 | } else { |
| 246 | da.mode = IEEE802154_ADDR_LONG; |
| 247 | da.extended_addr = ieee802154_devaddr_from_raw(daddr); |
Alexander Aring | c91208d | 2015-08-10 21:15:58 +0200 | [diff] [blame] | 248 | cb->ackreq = wpan_dev->ackreq; |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 249 | } |
| 250 | |
Alexander Aring | 838b83d | 2015-09-18 11:30:42 +0200 | [diff] [blame] | 251 | return wpan_dev_hard_header(skb, lowpan_dev_info(ldev)->wdev, &da, &sa, |
| 252 | 0); |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 253 | } |
| 254 | |
Alexander Aring | f460658 | 2015-09-02 14:21:16 +0200 | [diff] [blame] | 255 | netdev_tx_t lowpan_xmit(struct sk_buff *skb, struct net_device *ldev) |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 256 | { |
| 257 | struct ieee802154_hdr wpan_hdr; |
| 258 | int max_single, ret; |
Alexander Aring | 5f50923 | 2015-10-01 08:03:06 +0200 | [diff] [blame] | 259 | u16 dgram_size, dgram_offset; |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 260 | |
| 261 | pr_debug("package xmit\n"); |
| 262 | |
Alexander Aring | 5f50923 | 2015-10-01 08:03:06 +0200 | [diff] [blame] | 263 | WARN_ON_ONCE(skb->len > IPV6_MIN_MTU); |
| 264 | |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 265 | /* We must take a copy of the skb before we modify/replace the ipv6 |
| 266 | * header as the header could be used elsewhere |
| 267 | */ |
| 268 | skb = skb_unshare(skb, GFP_ATOMIC); |
| 269 | if (!skb) |
| 270 | return NET_XMIT_DROP; |
| 271 | |
Alexander Aring | 187625e | 2015-09-02 14:21:31 +0200 | [diff] [blame] | 272 | ret = lowpan_header(skb, ldev, &dgram_size, &dgram_offset); |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 273 | if (ret < 0) { |
| 274 | kfree_skb(skb); |
| 275 | return NET_XMIT_DROP; |
| 276 | } |
| 277 | |
| 278 | if (ieee802154_hdr_peek(skb, &wpan_hdr) < 0) { |
| 279 | kfree_skb(skb); |
| 280 | return NET_XMIT_DROP; |
| 281 | } |
| 282 | |
| 283 | max_single = ieee802154_max_payload(&wpan_hdr); |
| 284 | |
| 285 | if (skb_tail_pointer(skb) - skb_network_header(skb) <= max_single) { |
Alexander Aring | f460658 | 2015-09-02 14:21:16 +0200 | [diff] [blame] | 286 | skb->dev = lowpan_dev_info(ldev)->wdev; |
Alexander Aring | 1c64f14 | 2015-09-30 10:20:11 +0200 | [diff] [blame] | 287 | ldev->stats.tx_packets++; |
| 288 | ldev->stats.tx_bytes += dgram_size; |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 289 | return dev_queue_xmit(skb); |
| 290 | } else { |
| 291 | netdev_tx_t rc; |
| 292 | |
| 293 | pr_debug("frame is too big, fragmentation is needed\n"); |
Alexander Aring | 187625e | 2015-09-02 14:21:31 +0200 | [diff] [blame] | 294 | rc = lowpan_xmit_fragmented(skb, ldev, &wpan_hdr, dgram_size, |
| 295 | dgram_offset); |
Alexander Aring | 4dc315e | 2015-01-04 17:10:56 +0100 | [diff] [blame] | 296 | |
| 297 | return rc < 0 ? NET_XMIT_DROP : rc; |
| 298 | } |
| 299 | } |