diff options
Diffstat (limited to 'net/ieee802154')
-rw-r--r-- | net/ieee802154/6lowpan.c | 286 | ||||
-rw-r--r-- | net/ieee802154/6lowpan.h | 20 |
2 files changed, 204 insertions, 102 deletions
diff --git a/net/ieee802154/6lowpan.c b/net/ieee802154/6lowpan.c index 3b9d5f2..c85e71e 100644 --- a/net/ieee802154/6lowpan.c +++ b/net/ieee802154/6lowpan.c @@ -67,39 +67,6 @@ static const u8 lowpan_ttl_values[] = {0, 1, 64, 255}; static LIST_HEAD(lowpan_devices); -/* - * Uncompression of linklocal: - * 0 -> 16 bytes from packet - * 1 -> 2 bytes from prefix - bunch of zeroes and 8 from packet - * 2 -> 2 bytes from prefix - zeroes + 2 from packet - * 3 -> 2 bytes from prefix - infer 8 bytes from lladdr - * - * NOTE: => the uncompress function does change 0xf to 0x10 - * NOTE: 0x00 => no-autoconfig => unspecified - */ -static const u8 lowpan_unc_llconf[] = {0x0f, 0x28, 0x22, 0x20}; - -/* - * Uncompression of ctx-based: - * 0 -> 0 bits from packet [unspecified / reserved] - * 1 -> 8 bytes from prefix - bunch of zeroes and 8 from packet - * 2 -> 8 bytes from prefix - zeroes + 2 from packet - * 3 -> 8 bytes from prefix - infer 8 bytes from lladdr - */ -static const u8 lowpan_unc_ctxconf[] = {0x00, 0x88, 0x82, 0x80}; - -/* - * Uncompression of ctx-base - * 0 -> 0 bits from packet - * 1 -> 2 bytes from prefix - bunch of zeroes 5 from packet - * 2 -> 2 bytes from prefix - zeroes + 3 from packet - * 3 -> 2 bytes from prefix - infer 1 bytes from lladdr - */ -static const u8 lowpan_unc_mxconf[] = {0x0f, 0x25, 0x23, 0x21}; - -/* Link local prefix */ -static const u8 lowpan_llprefix[] = {0xfe, 0x80}; - /* private device info */ struct lowpan_dev_info { struct net_device *real_dev; /* real WPAN device ptr */ @@ -191,55 +158,177 @@ lowpan_compress_addr_64(u8 **hc06_ptr, u8 shift, const struct in6_addr *ipaddr, return rol8(val, shift); } -static void -lowpan_uip_ds6_set_addr_iid(struct in6_addr *ipaddr, unsigned char *lladdr) +/* + * Uncompress address function for source and + * destination address(non-multicast). + * + * address_mode is sam value or dam value. + */ +static int +lowpan_uncompress_addr(struct sk_buff *skb, + struct in6_addr *ipaddr, + const u8 address_mode, + const struct ieee802154_addr *lladdr) { - memcpy(&ipaddr->s6_addr[8], lladdr, IEEE802154_ADDR_LEN); - /* second bit-flip (Universe/Local) is done according RFC2464 */ - ipaddr->s6_addr[8] ^= 0x02; + bool fail; + + switch (address_mode) { + case LOWPAN_IPHC_ADDR_00: + /* for global link addresses */ + fail = lowpan_fetch_skb(skb, ipaddr->s6_addr, 16); + break; + case LOWPAN_IPHC_ADDR_01: + /* fe:80::XXXX:XXXX:XXXX:XXXX */ + ipaddr->s6_addr[0] = 0xFE; + ipaddr->s6_addr[1] = 0x80; + fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[8], 8); + break; + case LOWPAN_IPHC_ADDR_02: + /* fe:80::ff:fe00:XXXX */ + ipaddr->s6_addr[0] = 0xFE; + ipaddr->s6_addr[1] = 0x80; + ipaddr->s6_addr[11] = 0xFF; + ipaddr->s6_addr[12] = 0xFE; + fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[14], 2); + break; + case LOWPAN_IPHC_ADDR_03: + fail = false; + switch (lladdr->addr_type) { + case IEEE802154_ADDR_LONG: + /* fe:80::XXXX:XXXX:XXXX:XXXX + * \_________________/ + * hwaddr + */ + ipaddr->s6_addr[0] = 0xFE; + ipaddr->s6_addr[1] = 0x80; + memcpy(&ipaddr->s6_addr[8], lladdr->hwaddr, + IEEE802154_ADDR_LEN); + /* second bit-flip (Universe/Local) + * is done according RFC2464 + */ + ipaddr->s6_addr[8] ^= 0x02; + break; + case IEEE802154_ADDR_SHORT: + /* fe:80::ff:fe00:XXXX + * \__/ + * short_addr + * + * Universe/Local bit is zero. + */ + ipaddr->s6_addr[0] = 0xFE; + ipaddr->s6_addr[1] = 0x80; + ipaddr->s6_addr[11] = 0xFF; + ipaddr->s6_addr[12] = 0xFE; + ipaddr->s6_addr16[7] = htons(lladdr->short_addr); + break; + default: + pr_debug("Invalid addr_type set\n"); + return -EINVAL; + } + break; + default: + pr_debug("Invalid address mode value: 0x%x\n", address_mode); + return -EINVAL; + } + + if (fail) { + pr_debug("Failed to fetch skb data\n"); + return -EIO; + } + + lowpan_raw_dump_inline(NULL, "Reconstructed ipv6 addr is:\n", + ipaddr->s6_addr, 16); + + return 0; } -/* - * Uncompress addresses based on a prefix and a postfix with zeroes in - * between. If the postfix is zero in length it will use the link address - * to configure the IP address (autoconf style). - * pref_post_count takes a byte where the first nibble specify prefix count - * and the second postfix count (NOTE: 15/0xf => 16 bytes copy). +/* Uncompress address function for source context + * based address(non-multicast). */ static int -lowpan_uncompress_addr(struct sk_buff *skb, struct in6_addr *ipaddr, - u8 const *prefix, u8 pref_post_count, unsigned char *lladdr) +lowpan_uncompress_context_based_src_addr(struct sk_buff *skb, + struct in6_addr *ipaddr, + const u8 sam) { - u8 prefcount = pref_post_count >> 4; - u8 postcount = pref_post_count & 0x0f; - - /* full nibble 15 => 16 */ - prefcount = (prefcount == 15 ? 16 : prefcount); - postcount = (postcount == 15 ? 16 : postcount); - - if (lladdr) - lowpan_raw_dump_inline(__func__, "linklocal address", - lladdr, IEEE802154_ADDR_LEN); - if (prefcount > 0) - memcpy(ipaddr, prefix, prefcount); - - if (prefcount + postcount < 16) - memset(&ipaddr->s6_addr[prefcount], 0, - 16 - (prefcount + postcount)); - - if (postcount > 0) { - memcpy(&ipaddr->s6_addr[16 - postcount], skb->data, postcount); - skb_pull(skb, postcount); - } else if (prefcount > 0) { - if (lladdr == NULL) - return -EINVAL; + switch (sam) { + case LOWPAN_IPHC_ADDR_00: + /* unspec address :: + * Do nothing, address is already :: + */ + break; + case LOWPAN_IPHC_ADDR_01: + /* TODO */ + case LOWPAN_IPHC_ADDR_02: + /* TODO */ + case LOWPAN_IPHC_ADDR_03: + /* TODO */ + netdev_warn(skb->dev, "SAM value 0x%x not supported\n", sam); + return -EINVAL; + default: + pr_debug("Invalid sam value: 0x%x\n", sam); + return -EINVAL; + } + + lowpan_raw_dump_inline(NULL, + "Reconstructed context based ipv6 src addr is:\n", + ipaddr->s6_addr, 16); + + return 0; +} - /* no IID based configuration if no prefix and no data */ - lowpan_uip_ds6_set_addr_iid(ipaddr, lladdr); +/* Uncompress function for multicast destination address, + * when M bit is set. + */ +static int +lowpan_uncompress_multicast_daddr(struct sk_buff *skb, + struct in6_addr *ipaddr, + const u8 dam) +{ + bool fail; + + switch (dam) { + case LOWPAN_IPHC_DAM_00: + /* 00: 128 bits. The full address + * is carried in-line. + */ + fail = lowpan_fetch_skb(skb, ipaddr->s6_addr, 16); + break; + case LOWPAN_IPHC_DAM_01: + /* 01: 48 bits. The address takes + * the form ffXX::00XX:XXXX:XXXX. + */ + ipaddr->s6_addr[0] = 0xFF; + fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[1], 1); + fail |= lowpan_fetch_skb(skb, &ipaddr->s6_addr[11], 5); + break; + case LOWPAN_IPHC_DAM_10: + /* 10: 32 bits. The address takes + * the form ffXX::00XX:XXXX. + */ + ipaddr->s6_addr[0] = 0xFF; + fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[1], 1); + fail |= lowpan_fetch_skb(skb, &ipaddr->s6_addr[13], 3); + break; + case LOWPAN_IPHC_DAM_11: + /* 11: 8 bits. The address takes + * the form ff02::00XX. + */ + ipaddr->s6_addr[0] = 0xFF; + ipaddr->s6_addr[1] = 0x02; + fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[15], 1); + break; + default: + pr_debug("DAM value has a wrong value: 0x%x\n", dam); + return -EINVAL; + } + + if (fail) { + pr_debug("Failed to fetch skb data\n"); + return -EIO; } - pr_debug("uncompressing %d + %d => ", prefcount, postcount); - lowpan_raw_dump_inline(NULL, NULL, ipaddr->s6_addr, 16); + lowpan_raw_dump_inline(NULL, "Reconstructed ipv6 multicast addr is:\n", + ipaddr->s6_addr, 16); return 0; } @@ -702,6 +791,12 @@ lowpan_alloc_new_frame(struct sk_buff *skb, u16 len, u16 tag) skb_reserve(frame->skb, sizeof(struct ipv6hdr)); skb_put(frame->skb, frame->length); + /* copy the first control block to keep a + * trace of the link-layer addresses in case + * of a link-local compressed address + */ + memcpy(frame->skb->cb, skb->cb, sizeof(skb->cb)); + init_timer(&frame->timer); /* time out is the same as for ipv6 - 60 sec */ frame->timer.expires = jiffies + LOWPAN_FRAG_TIMEOUT; @@ -723,9 +818,9 @@ frame_err: static int lowpan_process_data(struct sk_buff *skb) { - struct ipv6hdr hdr; + struct ipv6hdr hdr = {}; u8 tmp, iphc0, iphc1, num_context = 0; - u8 *_saddr, *_daddr; + const struct ieee802154_addr *_saddr, *_daddr; int err; lowpan_raw_dump_table(__func__, "raw skb data dump", skb->data, @@ -828,8 +923,8 @@ lowpan_process_data(struct sk_buff *skb) if (lowpan_fetch_skb_u8(skb, &iphc1)) goto drop; - _saddr = mac_cb(skb)->sa.hwaddr; - _daddr = mac_cb(skb)->da.hwaddr; + _saddr = &mac_cb(skb)->sa; + _daddr = &mac_cb(skb)->da; pr_debug("iphc0 = %02x, iphc1 = %02x\n", iphc0, iphc1); @@ -868,8 +963,6 @@ lowpan_process_data(struct sk_buff *skb) hdr.priority = ((tmp >> 2) & 0x0f); hdr.flow_lbl[0] = ((tmp << 6) & 0xC0) | ((tmp >> 2) & 0x30); - hdr.flow_lbl[1] = 0; - hdr.flow_lbl[2] = 0; break; /* * Flow Label carried in-line @@ -885,10 +978,6 @@ lowpan_process_data(struct sk_buff *skb) break; /* Traffic Class and Flow Label are elided */ case 3: /* 11b */ - hdr.priority = 0; - hdr.flow_lbl[0] = 0; - hdr.flow_lbl[1] = 0; - hdr.flow_lbl[2] = 0; break; default: break; @@ -915,10 +1004,18 @@ lowpan_process_data(struct sk_buff *skb) /* Extract SAM to the tmp variable */ tmp = ((iphc1 & LOWPAN_IPHC_SAM) >> LOWPAN_IPHC_SAM_BIT) & 0x03; - /* Source address uncompression */ - pr_debug("source address stateless compression\n"); - err = lowpan_uncompress_addr(skb, &hdr.saddr, lowpan_llprefix, - lowpan_unc_llconf[tmp], skb->data); + if (iphc1 & LOWPAN_IPHC_SAC) { + /* Source address context based uncompression */ + pr_debug("SAC bit is set. Handle context based source address.\n"); + err = lowpan_uncompress_context_based_src_addr( + skb, &hdr.saddr, tmp); + } else { + /* Source address uncompression */ + pr_debug("source address stateless compression\n"); + err = lowpan_uncompress_addr(skb, &hdr.saddr, tmp, _saddr); + } + + /* Check on error of previous branch */ if (err) goto drop; @@ -931,23 +1028,14 @@ lowpan_process_data(struct sk_buff *skb) pr_debug("dest: context-based mcast compression\n"); /* TODO: implement this */ } else { - u8 prefix[] = {0xff, 0x02}; - - pr_debug("dest: non context-based mcast compression\n"); - if (0 < tmp && tmp < 3) { - if (lowpan_fetch_skb_u8(skb, &prefix[1])) - goto drop; - } - - err = lowpan_uncompress_addr(skb, &hdr.daddr, prefix, - lowpan_unc_mxconf[tmp], NULL); + err = lowpan_uncompress_multicast_daddr( + skb, &hdr.daddr, tmp); if (err) goto drop; } } else { pr_debug("dest: stateless compression\n"); - err = lowpan_uncompress_addr(skb, &hdr.daddr, lowpan_llprefix, - lowpan_unc_llconf[tmp], skb->data); + err = lowpan_uncompress_addr(skb, &hdr.daddr, tmp, _daddr); if (err) goto drop; } diff --git a/net/ieee802154/6lowpan.h b/net/ieee802154/6lowpan.h index 4b8f917..2869c05 100644 --- a/net/ieee802154/6lowpan.h +++ b/net/ieee802154/6lowpan.h @@ -193,10 +193,12 @@ /* Values of fields within the IPHC encoding second byte */ #define LOWPAN_IPHC_CID 0x80 +#define LOWPAN_IPHC_ADDR_00 0x00 +#define LOWPAN_IPHC_ADDR_01 0x01 +#define LOWPAN_IPHC_ADDR_02 0x02 +#define LOWPAN_IPHC_ADDR_03 0x03 + #define LOWPAN_IPHC_SAC 0x40 -#define LOWPAN_IPHC_SAM_00 0x00 -#define LOWPAN_IPHC_SAM_01 0x10 -#define LOWPAN_IPHC_SAM_10 0x20 #define LOWPAN_IPHC_SAM 0x30 #define LOWPAN_IPHC_SAM_BIT 4 @@ -230,4 +232,16 @@ dest = 16 bit inline */ #define LOWPAN_NHC_UDP_CS_P_11 0xF3 /* source & dest = 0xF0B + 4bit inline */ +static inline bool lowpan_fetch_skb(struct sk_buff *skb, + void *data, const unsigned int len) +{ + if (unlikely(!pskb_may_pull(skb, len))) + return true; + + skb_copy_from_linear_data(skb, data, len); + skb_pull(skb, len); + + return false; +} + #endif /* __6LOWPAN_H__ */ |