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-rw-r--r--net/6lowpan/iphc.c413
1 files changed, 357 insertions, 56 deletions
diff --git a/net/6lowpan/iphc.c b/net/6lowpan/iphc.c
index 346b5c1a9185..99bb22aea346 100644
--- a/net/6lowpan/iphc.c
+++ b/net/6lowpan/iphc.c
@@ -56,6 +56,7 @@
/* special link-layer handling */
#include <net/mac802154.h>
+#include "6lowpan_i.h"
#include "nhc.h"
/* Values of fields within the IPHC encoding first byte */
@@ -147,6 +148,9 @@
(((a)->s6_addr16[6]) == 0) && \
(((a)->s6_addr[14]) == 0))
+#define LOWPAN_IPHC_CID_DCI(cid) (cid & 0x0f)
+#define LOWPAN_IPHC_CID_SCI(cid) ((cid & 0xf0) >> 4)
+
static inline void iphc_uncompress_eui64_lladdr(struct in6_addr *ipaddr,
const void *lladdr)
{
@@ -195,6 +199,98 @@ static inline void iphc_uncompress_802154_lladdr(struct in6_addr *ipaddr,
}
}
+static struct lowpan_iphc_ctx *
+lowpan_iphc_ctx_get_by_id(const struct net_device *dev, u8 id)
+{
+ struct lowpan_iphc_ctx *ret = &lowpan_priv(dev)->ctx.table[id];
+
+ if (!lowpan_iphc_ctx_is_active(ret))
+ return NULL;
+
+ return ret;
+}
+
+static struct lowpan_iphc_ctx *
+lowpan_iphc_ctx_get_by_addr(const struct net_device *dev,
+ const struct in6_addr *addr)
+{
+ struct lowpan_iphc_ctx *table = lowpan_priv(dev)->ctx.table;
+ struct lowpan_iphc_ctx *ret = NULL;
+ struct in6_addr addr_pfx;
+ u8 addr_plen;
+ int i;
+
+ for (i = 0; i < LOWPAN_IPHC_CTX_TABLE_SIZE; i++) {
+ /* Check if context is valid. A context that is not valid
+ * MUST NOT be used for compression.
+ */
+ if (!lowpan_iphc_ctx_is_active(&table[i]) ||
+ !lowpan_iphc_ctx_is_compression(&table[i]))
+ continue;
+
+ ipv6_addr_prefix(&addr_pfx, addr, table[i].plen);
+
+ /* if prefix len < 64, the remaining bits until 64th bit is
+ * zero. Otherwise we use table[i]->plen.
+ */
+ if (table[i].plen < 64)
+ addr_plen = 64;
+ else
+ addr_plen = table[i].plen;
+
+ if (ipv6_prefix_equal(&addr_pfx, &table[i].pfx, addr_plen)) {
+ /* remember first match */
+ if (!ret) {
+ ret = &table[i];
+ continue;
+ }
+
+ /* get the context with longest prefix len */
+ if (table[i].plen > ret->plen)
+ ret = &table[i];
+ }
+ }
+
+ return ret;
+}
+
+static struct lowpan_iphc_ctx *
+lowpan_iphc_ctx_get_by_mcast_addr(const struct net_device *dev,
+ const struct in6_addr *addr)
+{
+ struct lowpan_iphc_ctx *table = lowpan_priv(dev)->ctx.table;
+ struct lowpan_iphc_ctx *ret = NULL;
+ struct in6_addr addr_mcast, network_pfx = {};
+ int i;
+
+ /* init mcast address with */
+ memcpy(&addr_mcast, addr, sizeof(*addr));
+
+ for (i = 0; i < LOWPAN_IPHC_CTX_TABLE_SIZE; i++) {
+ /* Check if context is valid. A context that is not valid
+ * MUST NOT be used for compression.
+ */
+ if (!lowpan_iphc_ctx_is_active(&table[i]) ||
+ !lowpan_iphc_ctx_is_compression(&table[i]))
+ continue;
+
+ /* setting plen */
+ addr_mcast.s6_addr[3] = table[i].plen;
+ /* get network prefix to copy into multicast address */
+ ipv6_addr_prefix(&network_pfx, &table[i].pfx,
+ table[i].plen);
+ /* setting network prefix */
+ memcpy(&addr_mcast.s6_addr[4], &network_pfx, 8);
+
+ if (ipv6_addr_equal(addr, &addr_mcast)) {
+ ret = &table[i];
+ break;
+ }
+ }
+
+ return ret;
+}
+
/* Uncompress address function for source and
* destination address(non-multicast).
*
@@ -259,30 +355,59 @@ static int uncompress_addr(struct sk_buff *skb, const struct net_device *dev,
/* Uncompress address function for source context
* based address(non-multicast).
*/
-static int uncompress_context_based_src_addr(struct sk_buff *skb,
- struct in6_addr *ipaddr,
- u8 address_mode)
+static int uncompress_ctx_addr(struct sk_buff *skb,
+ const struct net_device *dev,
+ const struct lowpan_iphc_ctx *ctx,
+ struct in6_addr *ipaddr, u8 address_mode,
+ const void *lladdr)
{
+ bool fail;
+
switch (address_mode) {
- case LOWPAN_IPHC_SAM_00:
- /* unspec address ::
+ /* SAM and DAM are the same here */
+ case LOWPAN_IPHC_DAM_00:
+ fail = false;
+ /* SAM_00 -> unspec address ::
* Do nothing, address is already ::
+ *
+ * DAM 00 -> reserved should never occur.
*/
break;
case LOWPAN_IPHC_SAM_01:
- /* TODO */
+ case LOWPAN_IPHC_DAM_01:
+ fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[8], 8);
+ ipv6_addr_prefix_copy(ipaddr, &ctx->pfx, ctx->plen);
+ break;
case LOWPAN_IPHC_SAM_10:
- /* TODO */
+ case LOWPAN_IPHC_DAM_10:
+ ipaddr->s6_addr[11] = 0xFF;
+ ipaddr->s6_addr[12] = 0xFE;
+ fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[14], 2);
+ ipv6_addr_prefix_copy(ipaddr, &ctx->pfx, ctx->plen);
+ break;
case LOWPAN_IPHC_SAM_11:
- /* TODO */
- netdev_warn(skb->dev, "SAM value 0x%x not supported\n",
- address_mode);
- return -EINVAL;
+ case LOWPAN_IPHC_DAM_11:
+ fail = false;
+ switch (lowpan_priv(dev)->lltype) {
+ case LOWPAN_LLTYPE_IEEE802154:
+ iphc_uncompress_802154_lladdr(ipaddr, lladdr);
+ break;
+ default:
+ iphc_uncompress_eui64_lladdr(ipaddr, lladdr);
+ break;
+ }
+ ipv6_addr_prefix_copy(ipaddr, &ctx->pfx, ctx->plen);
+ break;
default:
pr_debug("Invalid sam value: 0x%x\n", address_mode);
return -EINVAL;
}
+ if (fail) {
+ pr_debug("Failed to fetch skb data\n");
+ return -EIO;
+ }
+
raw_dump_inline(NULL,
"Reconstructed context based ipv6 src addr is",
ipaddr->s6_addr, 16);
@@ -346,6 +471,30 @@ static int lowpan_uncompress_multicast_daddr(struct sk_buff *skb,
return 0;
}
+static int lowpan_uncompress_multicast_ctx_daddr(struct sk_buff *skb,
+ struct lowpan_iphc_ctx *ctx,
+ struct in6_addr *ipaddr,
+ u8 address_mode)
+{
+ struct in6_addr network_pfx = {};
+ bool fail;
+
+ ipaddr->s6_addr[0] = 0xFF;
+ fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[1], 2);
+ fail |= lowpan_fetch_skb(skb, &ipaddr->s6_addr[12], 4);
+ if (fail)
+ return -EIO;
+
+ /* take prefix_len and network prefix from the context */
+ ipaddr->s6_addr[3] = ctx->plen;
+ /* get network prefix to copy into multicast address */
+ ipv6_addr_prefix(&network_pfx, &ctx->pfx, ctx->plen);
+ /* setting network prefix */
+ memcpy(&ipaddr->s6_addr[4], &network_pfx, 8);
+
+ return 0;
+}
+
/* get the ecn values from iphc tf format and set it to ipv6hdr */
static inline void lowpan_iphc_tf_set_ecn(struct ipv6hdr *hdr, const u8 *tf)
{
@@ -459,7 +608,8 @@ int lowpan_header_decompress(struct sk_buff *skb, const struct net_device *dev,
const void *daddr, const void *saddr)
{
struct ipv6hdr hdr = {};
- u8 iphc0, iphc1;
+ struct lowpan_iphc_ctx *ci;
+ u8 iphc0, iphc1, cid = 0;
int err;
raw_dump_table(__func__, "raw skb data dump uncompressed",
@@ -469,12 +619,14 @@ int lowpan_header_decompress(struct sk_buff *skb, const struct net_device *dev,
lowpan_fetch_skb(skb, &iphc1, sizeof(iphc1)))
return -EINVAL;
- /* another if the CID flag is set */
- if (iphc1 & LOWPAN_IPHC_CID)
- return -ENOTSUPP;
-
hdr.version = 6;
+ /* default CID = 0, another if the CID flag is set */
+ if (iphc1 & LOWPAN_IPHC_CID) {
+ if (lowpan_fetch_skb(skb, &cid, sizeof(cid)))
+ return -EINVAL;
+ }
+
err = lowpan_iphc_tf_decompress(skb, &hdr,
iphc0 & LOWPAN_IPHC_TF_MASK);
if (err < 0)
@@ -500,10 +652,17 @@ int lowpan_header_decompress(struct sk_buff *skb, const struct net_device *dev,
}
if (iphc1 & LOWPAN_IPHC_SAC) {
- /* Source address context based uncompression */
+ spin_lock_bh(&lowpan_priv(dev)->ctx.lock);
+ ci = lowpan_iphc_ctx_get_by_id(dev, LOWPAN_IPHC_CID_SCI(cid));
+ if (!ci) {
+ spin_unlock_bh(&lowpan_priv(dev)->ctx.lock);
+ return -EINVAL;
+ }
+
pr_debug("SAC bit is set. Handle context based source address.\n");
- err = uncompress_context_based_src_addr(skb, &hdr.saddr,
- iphc1 & LOWPAN_IPHC_SAM_MASK);
+ err = uncompress_ctx_addr(skb, dev, ci, &hdr.saddr,
+ iphc1 & LOWPAN_IPHC_SAM_MASK, saddr);
+ spin_unlock_bh(&lowpan_priv(dev)->ctx.lock);
} else {
/* Source address uncompression */
pr_debug("source address stateless compression\n");
@@ -515,27 +674,52 @@ int lowpan_header_decompress(struct sk_buff *skb, const struct net_device *dev,
if (err)
return -EINVAL;
- /* check for Multicast Compression */
- if (iphc1 & LOWPAN_IPHC_M) {
- if (iphc1 & LOWPAN_IPHC_DAC) {
- pr_debug("dest: context-based mcast compression\n");
- /* TODO: implement this */
- } else {
- err = lowpan_uncompress_multicast_daddr(skb, &hdr.daddr,
- iphc1 & LOWPAN_IPHC_DAM_MASK);
+ switch (iphc1 & (LOWPAN_IPHC_M | LOWPAN_IPHC_DAC)) {
+ case LOWPAN_IPHC_M | LOWPAN_IPHC_DAC:
+ spin_lock_bh(&lowpan_priv(dev)->ctx.lock);
+ ci = lowpan_iphc_ctx_get_by_id(dev, LOWPAN_IPHC_CID_DCI(cid));
+ if (!ci) {
+ spin_unlock_bh(&lowpan_priv(dev)->ctx.lock);
+ return -EINVAL;
+ }
- if (err)
- return -EINVAL;
+ /* multicast with context */
+ pr_debug("dest: context-based mcast compression\n");
+ err = lowpan_uncompress_multicast_ctx_daddr(skb, ci,
+ &hdr.daddr,
+ iphc1 & LOWPAN_IPHC_DAM_MASK);
+ spin_unlock_bh(&lowpan_priv(dev)->ctx.lock);
+ break;
+ case LOWPAN_IPHC_M:
+ /* multicast */
+ err = lowpan_uncompress_multicast_daddr(skb, &hdr.daddr,
+ iphc1 & LOWPAN_IPHC_DAM_MASK);
+ break;
+ case LOWPAN_IPHC_DAC:
+ spin_lock_bh(&lowpan_priv(dev)->ctx.lock);
+ ci = lowpan_iphc_ctx_get_by_id(dev, LOWPAN_IPHC_CID_DCI(cid));
+ if (!ci) {
+ spin_unlock_bh(&lowpan_priv(dev)->ctx.lock);
+ return -EINVAL;
}
- } else {
+
+ /* Destination address context based uncompression */
+ pr_debug("DAC bit is set. Handle context based destination address.\n");
+ err = uncompress_ctx_addr(skb, dev, ci, &hdr.daddr,
+ iphc1 & LOWPAN_IPHC_DAM_MASK, daddr);
+ spin_unlock_bh(&lowpan_priv(dev)->ctx.lock);
+ break;
+ default:
err = uncompress_addr(skb, dev, &hdr.daddr,
iphc1 & LOWPAN_IPHC_DAM_MASK, daddr);
pr_debug("dest: stateless compression mode %d dest %pI6c\n",
iphc1 & LOWPAN_IPHC_DAM_MASK, &hdr.daddr);
- if (err)
- return -EINVAL;
+ break;
}
+ if (err)
+ return -EINVAL;
+
/* Next header data uncompression */
if (iphc0 & LOWPAN_IPHC_NH) {
err = lowpan_nhc_do_uncompression(skb, dev, &hdr);
@@ -585,6 +769,58 @@ static const u8 lowpan_iphc_dam_to_sam_value[] = {
[LOWPAN_IPHC_DAM_11] = LOWPAN_IPHC_SAM_11,
};
+static u8 lowpan_compress_ctx_addr(u8 **hc_ptr, const struct in6_addr *ipaddr,
+ const struct lowpan_iphc_ctx *ctx,
+ const unsigned char *lladdr, bool sam)
+{
+ struct in6_addr tmp = {};
+ u8 dam;
+
+ /* check for SAM/DAM = 11 */
+ memcpy(&tmp.s6_addr[8], lladdr, 8);
+ /* second bit-flip (Universe/Local) is done according RFC2464 */
+ tmp.s6_addr[8] ^= 0x02;
+ /* context information are always used */
+ ipv6_addr_prefix_copy(&tmp, &ctx->pfx, ctx->plen);
+ if (ipv6_addr_equal(&tmp, ipaddr)) {
+ dam = LOWPAN_IPHC_DAM_11;
+ goto out;
+ }
+
+ memset(&tmp, 0, sizeof(tmp));
+ /* check for SAM/DAM = 10 */
+ tmp.s6_addr[11] = 0xFF;
+ tmp.s6_addr[12] = 0xFE;
+ memcpy(&tmp.s6_addr[14], &ipaddr->s6_addr[14], 2);
+ /* context information are always used */
+ ipv6_addr_prefix_copy(&tmp, &ctx->pfx, ctx->plen);
+ if (ipv6_addr_equal(&tmp, ipaddr)) {
+ lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[14], 2);
+ dam = LOWPAN_IPHC_DAM_10;
+ goto out;
+ }
+
+ memset(&tmp, 0, sizeof(tmp));
+ /* check for SAM/DAM = 01, should always match */
+ memcpy(&tmp.s6_addr[8], &ipaddr->s6_addr[8], 8);
+ /* context information are always used */
+ ipv6_addr_prefix_copy(&tmp, &ctx->pfx, ctx->plen);
+ if (ipv6_addr_equal(&tmp, ipaddr)) {
+ lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[8], 8);
+ dam = LOWPAN_IPHC_DAM_01;
+ goto out;
+ }
+
+ WARN_ONCE(1, "context found but no address mode matched\n");
+ return LOWPAN_IPHC_DAM_00;
+out:
+
+ if (sam)
+ return lowpan_iphc_dam_to_sam_value[dam];
+ else
+ return dam;
+}
+
static u8 lowpan_compress_addr_64(u8 **hc_ptr, const struct in6_addr *ipaddr,
const unsigned char *lladdr, bool sam)
{
@@ -708,6 +944,21 @@ static u8 lowpan_iphc_tf_compress(u8 **hc_ptr, const struct ipv6hdr *hdr)
return val;
}
+static u8 lowpan_iphc_mcast_ctx_addr_compress(u8 **hc_ptr,
+ const struct lowpan_iphc_ctx *ctx,
+ const struct in6_addr *ipaddr)
+{
+ u8 data[6];
+
+ /* flags/scope, reserved (RIID) */
+ memcpy(data, &ipaddr->s6_addr[1], 2);
+ /* group ID */
+ memcpy(&data[1], &ipaddr->s6_addr[11], 4);
+ lowpan_push_hc_data(hc_ptr, data, 6);
+
+ return LOWPAN_IPHC_DAM_00;
+}
+
static u8 lowpan_iphc_mcast_addr_compress(u8 **hc_ptr,
const struct in6_addr *ipaddr)
{
@@ -742,10 +993,11 @@ static u8 lowpan_iphc_mcast_addr_compress(u8 **hc_ptr,
int lowpan_header_compress(struct sk_buff *skb, const struct net_device *dev,
const void *daddr, const void *saddr)
{
- u8 iphc0, iphc1, *hc_ptr;
+ u8 iphc0, iphc1, *hc_ptr, cid = 0;
struct ipv6hdr *hdr;
u8 head[LOWPAN_IPHC_MAX_HC_BUF_LEN] = {};
- int ret, addr_type;
+ struct lowpan_iphc_ctx *dci, *sci, dci_entry, sci_entry;
+ int ret, ipv6_daddr_type, ipv6_saddr_type;
if (skb->protocol != htons(ETH_P_IPV6))
return -EINVAL;
@@ -769,14 +1021,38 @@ int lowpan_header_compress(struct sk_buff *skb, const struct net_device *dev,
iphc0 = LOWPAN_DISPATCH_IPHC;
iphc1 = 0;
- /* TODO: context lookup */
-
raw_dump_inline(__func__, "saddr", saddr, EUI64_ADDR_LEN);
raw_dump_inline(__func__, "daddr", daddr, EUI64_ADDR_LEN);
raw_dump_table(__func__, "sending raw skb network uncompressed packet",
skb->data, skb->len);
+ ipv6_daddr_type = ipv6_addr_type(&hdr->daddr);
+ spin_lock_bh(&lowpan_priv(dev)->ctx.lock);
+ if (ipv6_daddr_type & IPV6_ADDR_MULTICAST)
+ dci = lowpan_iphc_ctx_get_by_mcast_addr(dev, &hdr->daddr);
+ else
+ dci = lowpan_iphc_ctx_get_by_addr(dev, &hdr->daddr);
+ if (dci) {
+ memcpy(&dci_entry, dci, sizeof(*dci));
+ cid |= dci->id;
+ }
+ spin_unlock_bh(&lowpan_priv(dev)->ctx.lock);
+
+ spin_lock_bh(&lowpan_priv(dev)->ctx.lock);
+ sci = lowpan_iphc_ctx_get_by_addr(dev, &hdr->saddr);
+ if (sci) {
+ memcpy(&sci_entry, sci, sizeof(*sci));
+ cid |= (sci->id << 4);
+ }
+ spin_unlock_bh(&lowpan_priv(dev)->ctx.lock);
+
+ /* if cid is zero it will be compressed */
+ if (cid) {
+ iphc1 |= LOWPAN_IPHC_CID;
+ lowpan_push_hc_data(&hc_ptr, &cid, sizeof(cid));
+ }
+
/* Traffic Class, Flow Label compression */
iphc0 |= lowpan_iphc_tf_compress(&hc_ptr, hdr);
@@ -813,39 +1089,64 @@ int lowpan_header_compress(struct sk_buff *skb, const struct net_device *dev,
sizeof(hdr->hop_limit));
}
- addr_type = ipv6_addr_type(&hdr->saddr);
+ ipv6_saddr_type = ipv6_addr_type(&hdr->saddr);
/* source address compression */
- if (addr_type == IPV6_ADDR_ANY) {
+ if (ipv6_saddr_type == IPV6_ADDR_ANY) {
pr_debug("source address is unspecified, setting SAC\n");
iphc1 |= LOWPAN_IPHC_SAC;
} else {
- if (addr_type & IPV6_ADDR_LINKLOCAL) {
- iphc1 |= lowpan_compress_addr_64(&hc_ptr, &hdr->saddr,
- saddr, true);
- pr_debug("source address unicast link-local %pI6c iphc1 0x%02x\n",
- &hdr->saddr, iphc1);
+ if (sci) {
+ iphc1 |= lowpan_compress_ctx_addr(&hc_ptr, &hdr->saddr,
+ &sci_entry, saddr,
+ true);
+ iphc1 |= LOWPAN_IPHC_SAC;
} else {
- pr_debug("send the full source address\n");
- lowpan_push_hc_data(&hc_ptr, hdr->saddr.s6_addr, 16);
+ if (ipv6_saddr_type & IPV6_ADDR_LINKLOCAL) {
+ iphc1 |= lowpan_compress_addr_64(&hc_ptr,
+ &hdr->saddr,
+ saddr, true);
+ pr_debug("source address unicast link-local %pI6c iphc1 0x%02x\n",
+ &hdr->saddr, iphc1);
+ } else {
+ pr_debug("send the full source address\n");
+ lowpan_push_hc_data(&hc_ptr,
+ hdr->saddr.s6_addr, 16);
+ }
}
}
- addr_type = ipv6_addr_type(&hdr->daddr);
/* destination address compression */
- if (addr_type & IPV6_ADDR_MULTICAST) {
+ if (ipv6_daddr_type & IPV6_ADDR_MULTICAST) {
pr_debug("destination address is multicast: ");
iphc1 |= LOWPAN_IPHC_M;
- iphc1 |= lowpan_iphc_mcast_addr_compress(&hc_ptr, &hdr->daddr);
+ if (dci) {
+ iphc1 |= lowpan_iphc_mcast_ctx_addr_compress(&hc_ptr,
+ &dci_entry,
+ &hdr->daddr);
+ iphc1 |= LOWPAN_IPHC_DAC;
+ } else {
+ iphc1 |= lowpan_iphc_mcast_addr_compress(&hc_ptr,
+ &hdr->daddr);
+ }
} else {
- if (addr_type & IPV6_ADDR_LINKLOCAL) {
- /* TODO: context lookup */
- iphc1 |= lowpan_compress_addr_64(&hc_ptr, &hdr->daddr,
- daddr, false);
- pr_debug("dest address unicast link-local %pI6c "
- "iphc1 0x%02x\n", &hdr->daddr, iphc1);
+ if (dci) {
+ iphc1 |= lowpan_compress_ctx_addr(&hc_ptr, &hdr->daddr,
+ &dci_entry, daddr,
+ false);
+ iphc1 |= LOWPAN_IPHC_DAC;
} else {
- pr_debug("dest address unicast %pI6c\n", &hdr->daddr);
- lowpan_push_hc_data(&hc_ptr, hdr->daddr.s6_addr, 16);
+ if (ipv6_daddr_type & IPV6_ADDR_LINKLOCAL) {
+ iphc1 |= lowpan_compress_addr_64(&hc_ptr,
+ &hdr->daddr,
+ daddr, false);
+ pr_debug("dest address unicast link-local %pI6c iphc1 0x%02x\n",
+ &hdr->daddr, iphc1);
+ } else {
+ pr_debug("dest address unicast %pI6c\n",
+ &hdr->daddr);
+ lowpan_push_hc_data(&hc_ptr,
+ hdr->daddr.s6_addr, 16);
+ }
}
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-19 23:35:38 +0100