Subject: [RFC] batman-adv: Modified DAT structures and functions in order
to support both IPv4 and IPv6
In order to support DHT for IPv6 there was needed a general implementation for
the IP field in distributed-arp-table.c (now the IP is __be32 and this patch
will transform it to unsigned char *). Distinction between types is done
using a new enum.
Also all functions were changed to support this.
Signed-off-by: Mihail Costea <mihail.costea90(a)gmail.com>
---
distributed-arp-table.c | 234 ++++++++++++++++++++++++++++++++++++-----------
types.h | 21 ++++-
2 files changed, 197 insertions(+), 58 deletions(-)
diff --git a/distributed-arp-table.c b/distributed-arp-table.c
index 9215caa..ed6e817 100644
--- a/distributed-arp-table.c
+++ b/distributed-arp-table.c
@@ -20,6 +20,7 @@
#include <linux/if_ether.h>
#include <linux/if_arp.h>
#include <net/arp.h>
+#include <net/ipv6.h>
#include "main.h"
#include "hash.h"
@@ -31,6 +32,36 @@
#include "translation-table.h"
#include "unicast.h"
+/* Prints similar debug message for IPv4 and IPv6.
+ * At list one variable parameter should be the IP itself, and it should
+ * be placed correctly based on format prefix and format suffix arguments.
+ */
+#ifdef CONFIG_BATMAN_ADV_DEBUG
+
+#define batadv_dat_dbg_ip(bat_priv, ip_type, format_prefix, \
+ format_suffix, ...) \
+ { \
+ switch (ip_type) { \
+ case BATADV_DAT_IPv4: \
+ batadv_dbg(BATADV_DBG_DAT, bat_priv, \
+ format_prefix "%pI4" format_suffix, \
+ __VA_ARGS__); \
+ break; \
+ case BATADV_DAT_IPv6: \
+ batadv_dbg(BATADV_DBG_DAT, bat_priv, \
+ format_prefix "%pI6c" format_suffix, \
+ __VA_ARGS__); \
+ break; \
+ } \
+ }
+
+#else
+
+#define batadv_dat_dbg_ip(bat_priv, ip_type, format_prefix, \
+ format_suffix, ...) /* do nothing */
+
+#endif /* CONFIG_BATMAN_ADV_DEBUG */
+
static void batadv_dat_purge(struct work_struct *work);
/**
@@ -47,12 +78,14 @@ static void batadv_dat_start_timer(struct
batadv_priv *bat_priv)
/**
* batadv_dat_entry_free_ref - decrements the dat_entry refcounter and possibly
* free it
- * @dat_entry: the oentry to free
+ * @dat_entry: the entry to free
*/
static void batadv_dat_entry_free_ref(struct batadv_dat_entry *dat_entry)
{
- if (atomic_dec_and_test(&dat_entry->refcount))
+ if (atomic_dec_and_test(&dat_entry->refcount)) {
+ kfree(dat_entry->ip);
kfree_rcu(dat_entry, rcu);
+ }
}
/**
@@ -130,18 +163,50 @@ static void batadv_dat_purge(struct work_struct *work)
}
/**
+ * batadv_sizeof_ip - gets sizeof IP based on its type (IPv4 / IPv6)
+ * @ip_type: type of IP address
+ *
+ * Returns sizeof IP, or sizeof IPv4 if @ip_type is invalid
+ */
+static size_t batadv_sizeof_ip(uint8_t ip_type)
+{
+ switch (ip_type) {
+ case BATADV_DAT_IPv4:
+ return sizeof(__be32);
+ case BATADV_DAT_IPv6:
+ return sizeof(struct in6_addr);
+ default:
+ return sizeof(__be32); /* fallback to IPv4 */
+ }
+}
+
+/**
* batadv_compare_dat - comparing function used in the local DAT hash table
* @node: node in the local table
* @data2: second object to compare the node to
+ * @ip_type: type of IP address
*
* Returns 1 if the two entry are the same, 0 otherwise
*/
-static int batadv_compare_dat(const struct hlist_node *node, const void *data2)
+static int batadv_compare_dat(const struct hlist_node *node, const void *data2,
+ uint8_t ip_type)
{
const void *data1 = container_of(node, struct batadv_dat_entry,
hash_entry);
+ size_t ip_size = batadv_sizeof_ip(ip_type);
+ return (memcmp(data1, data2, ip_size) == 0 ? 1 : 0);
+}
- return (memcmp(data1, data2, sizeof(__be32)) == 0 ? 1 : 0);
+static int batadv_compare_dat_ipv4(const struct hlist_node *node,
+ const void *data2)
+{
+ return batadv_compare_dat(node, data2, BATADV_DAT_IPv4);
+}
+
+static int batadv_compare_dat_ipv6(const struct hlist_node *node,
+ const void *data2)
+{
+ return batadv_compare_dat(node, data2, BATADV_DAT_IPv6);
}
/**
@@ -201,16 +266,19 @@ static __be32 batadv_arp_ip_dst(struct sk_buff
*skb, int hdr_size)
* batadv_hash_dat - compute the hash value for an IP address
* @data: data to hash
* @size: size of the hash table
+ * @type: type of IP address
*
* Returns the selected index in the hash table for the given data
*/
-static uint32_t batadv_hash_dat(const void *data, uint32_t size)
+static uint32_t batadv_hash_dat(const void *data, uint32_t size,
+ uint8_t ip_type)
{
const unsigned char *key = data;
uint32_t hash = 0;
- size_t i;
+ size_t i, ip_size;
- for (i = 0; i < 4; i++) {
+ ip_size = batadv_sizeof_ip(ip_type);
+ for (i = 0; i < ip_size; i++) {
hash += key[i];
hash += (hash << 10);
hash ^= (hash >> 6);
@@ -223,32 +291,46 @@ static uint32_t batadv_hash_dat(const void
*data, uint32_t size)
return hash % size;
}
+static uint32_t batadv_hash_dat_ipv4(const void *data, uint32_t size)
+{
+ return batadv_hash_dat(data, size, BATADV_DAT_IPv4);
+}
+
+static uint32_t batadv_hash_dat_ipv6(const void *data, uint32_t size)
+{
+ return batadv_hash_dat(data, size, BATADV_DAT_IPv6);
+}
+
/**
* batadv_dat_entry_hash_find - looks for a given dat_entry in the local hash
* table
* @bat_priv: the bat priv with all the soft interface information
* @ip: search key
+ * @type: type of IP address
*
* Returns the dat_entry if found, NULL otherwise
*/
static struct batadv_dat_entry *
-batadv_dat_entry_hash_find(struct batadv_priv *bat_priv, __be32 ip)
+batadv_dat_entry_hash_find(struct batadv_priv *bat_priv, unsigned char *ip,
+ uint8_t ip_type)
{
struct hlist_head *head;
struct hlist_node *node;
struct batadv_dat_entry *dat_entry, *dat_entry_tmp = NULL;
struct batadv_hashtable *hash = bat_priv->dat.hash;
uint32_t index;
+ size_t ip_size;
if (!hash)
return NULL;
- index = batadv_hash_dat(&ip, hash->size);
+ ip_size = batadv_sizeof_ip(ip_type);
+ index = batadv_hash_dat(ip, hash->size, ip_type);
head = &hash->table[index];
rcu_read_lock();
hlist_for_each_entry_rcu(dat_entry, node, head, hash_entry) {
- if (dat_entry->ip != ip)
+ if (memcmp(dat_entry->ip, ip, ip_size))
continue;
if (!atomic_inc_not_zero(&dat_entry->refcount))
@@ -265,24 +347,26 @@ batadv_dat_entry_hash_find(struct batadv_priv
*bat_priv, __be32 ip)
/**
* batadv_dat_entry_add - add a new dat entry or update it if already exists
* @bat_priv: the bat priv with all the soft interface information
- * @ip: ipv4 to add/edit
+ * @ip: IP to add/edit
+ * @ip_type: type of IP address
* @mac_addr: mac address to assign to the given ipv4
*/
-static void batadv_dat_entry_add(struct batadv_priv *bat_priv, __be32 ip,
- uint8_t *mac_addr)
+static void batadv_dat_entry_add(struct batadv_priv *bat_priv,
+ unsigned char *ip, uint8_t ip_type, uint8_t *mac_addr)
{
struct batadv_dat_entry *dat_entry;
int hash_added;
+ size_t ip_size;
- dat_entry = batadv_dat_entry_hash_find(bat_priv, ip);
+ dat_entry = batadv_dat_entry_hash_find(bat_priv, ip, ip_type);
/* if this entry is already known, just update it */
if (dat_entry) {
if (!batadv_compare_eth(dat_entry->mac_addr, mac_addr))
memcpy(dat_entry->mac_addr, mac_addr, ETH_ALEN);
dat_entry->last_update = jiffies;
- batadv_dbg(BATADV_DBG_DAT, bat_priv,
- "Entry updated: %pI4 %pM\n", &dat_entry->ip,
- dat_entry->mac_addr);
+
+ batadv_dat_dbg_ip(bat_priv, ip_type, "Entry updated: ",
+ " %pM\n", dat_entry->ip, dat_entry->mac_addr);
goto out;
}
@@ -290,14 +374,32 @@ static void batadv_dat_entry_add(struct
batadv_priv *bat_priv, __be32 ip,
if (!dat_entry)
goto out;
- dat_entry->ip = ip;
+ ip_size = batadv_sizeof_ip(ip_type);
+ dat_entry->ip = kmalloc(ip_size, GFP_ATOMIC);
+ if (!dat_entry->ip)
+ goto out;
+ memcpy(dat_entry->ip, ip, ip_size);
+ dat_entry->type = ip_type;
+
memcpy(dat_entry->mac_addr, mac_addr, ETH_ALEN);
dat_entry->last_update = jiffies;
atomic_set(&dat_entry->refcount, 2);
- hash_added = batadv_hash_add(bat_priv->dat.hash, batadv_compare_dat,
- batadv_hash_dat, &dat_entry->ip,
- &dat_entry->hash_entry);
+ switch (ip_type) {
+ case BATADV_DAT_IPv4:
+ hash_added = batadv_hash_add(bat_priv->dat.hash,
+ batadv_compare_dat_ipv4, batadv_hash_dat_ipv4,
+ dat_entry->ip, &dat_entry->hash_entry);
+ break;
+ case BATADV_DAT_IPv6:
+ hash_added = batadv_hash_add(bat_priv->dat.hash,
+ batadv_compare_dat_ipv6, batadv_hash_dat_ipv6,
+ dat_entry->ip, &dat_entry->hash_entry);
+ break;
+ default:
+ hash_added = 1; /* In order to catch next if */
+ break;
+ }
if (unlikely(hash_added != 0)) {
/* remove the reference for the hash */
@@ -305,8 +407,8 @@ static void batadv_dat_entry_add(struct
batadv_priv *bat_priv, __be32 ip,
goto out;
}
- batadv_dbg(BATADV_DBG_DAT, bat_priv, "New entry added: %pI4 %pM\n",
- &dat_entry->ip, dat_entry->mac_addr);
+ batadv_dat_dbg_ip(bat_priv, ip_type, "New entry added: ", " %pM\n",
+ dat_entry->ip, dat_entry->mac_addr);
out:
if (dat_entry)
@@ -517,7 +619,8 @@ static void batadv_choose_next_candidate(struct
batadv_priv *bat_priv,
* batadv_dat_select_candidates - selects the nodes which the DHT
message has to
* be sent to
* @bat_priv: the bat priv with all the soft interface information
- * @ip_dst: ipv4 to look up in the DHT
+ * @ip_dst: IP to look up in the DHT
+ * @ip_type: type of IP address
*
* An originator O is selected if and only if its DHT_ID value is one of three
* closest values (from the LEFT, with wrap around if needed) then the hash
@@ -526,7 +629,8 @@ static void batadv_choose_next_candidate(struct
batadv_priv *bat_priv,
* Returns the candidate array of size BATADV_DAT_CANDIDATE_NUM
*/
static struct batadv_dat_candidate *
-batadv_dat_select_candidates(struct batadv_priv *bat_priv, __be32 ip_dst)
+batadv_dat_select_candidates(struct batadv_priv *bat_priv,
+ unsigned char *ip_dst, uint8_t ip_type)
{
int select;
batadv_dat_addr_t last_max = BATADV_DAT_ADDR_MAX, ip_key;
@@ -539,12 +643,11 @@ batadv_dat_select_candidates(struct batadv_priv
*bat_priv, __be32 ip_dst)
if (!res)
return NULL;
- ip_key = (batadv_dat_addr_t)batadv_hash_dat(&ip_dst,
- BATADV_DAT_ADDR_MAX);
+ ip_key = (batadv_dat_addr_t)batadv_hash_dat(ip_dst,
+ BATADV_DAT_ADDR_MAX, ip_type);
- batadv_dbg(BATADV_DBG_DAT, bat_priv,
- "dat_select_candidates(): IP=%pI4 hash(IP)=%u\n", &ip_dst,
- ip_key);
+ batadv_dat_dbg_ip(bat_priv, ip_type, "dat_select_candidates(): IP=",
+ " hash(IP)=%u\n", ip_dst, ip_key);
for (select = 0; select < BATADV_DAT_CANDIDATES_NUM; select++)
batadv_choose_next_candidate(bat_priv, res, select, ip_key,
@@ -558,6 +661,7 @@ batadv_dat_select_candidates(struct batadv_priv
*bat_priv, __be32 ip_dst)
* @bat_priv: the bat priv with all the soft interface information
* @skb: payload to send
* @ip: the DHT key
+ * @ip_type: type of IP address
* @packet_subtype: unicast4addr packet subtype to use
*
* In this function the skb is copied by means of pskb_copy() and is sent as
@@ -566,8 +670,8 @@ batadv_dat_select_candidates(struct batadv_priv
*bat_priv, __be32 ip_dst)
* Returns true if the packet is sent to at least one candidate,
false otherwise
*/
static bool batadv_dat_send_data(struct batadv_priv *bat_priv,
- struct sk_buff *skb, __be32 ip,
- int packet_subtype)
+ struct sk_buff *skb, unsigned char *ip,
+ uint8_t ip_type, int packet_subtype)
{
int i;
bool ret = false;
@@ -576,11 +680,12 @@ static bool batadv_dat_send_data(struct
batadv_priv *bat_priv,
struct sk_buff *tmp_skb;
struct batadv_dat_candidate *cand;
- cand = batadv_dat_select_candidates(bat_priv, ip);
+ cand = batadv_dat_select_candidates(bat_priv, (unsigned char *)ip,
+ ip_type);
if (!cand)
goto out;
- batadv_dbg(BATADV_DBG_DAT, bat_priv, "DHT_SEND for %pI4\n", &ip);
+ batadv_dat_dbg_ip(bat_priv, ip_type, "DHT_SEND for ", "\n", ip);
for (i = 0; i < BATADV_DAT_CANDIDATES_NUM; i++) {
if (cand[i].type == BATADV_DAT_CANDIDATE_NOT_FOUND)
@@ -697,8 +802,8 @@ int batadv_dat_cache_seq_print_text(struct
seq_file *seq, void *offset)
goto out;
seq_printf(seq, "Distributed ARP Table (%s):\n", net_dev->name);
- seq_printf(seq, " %-7s %-13s %5s\n", "IPv4", "MAC",
- "last-seen");
+ seq_printf(seq, " %-26s %-15s %5s\n",
+ "IPv4/IPv6", "MAC", "last-seen");
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
@@ -711,9 +816,18 @@ int batadv_dat_cache_seq_print_text(struct
seq_file *seq, void *offset)
last_seen_msecs = last_seen_msecs % 60000;
last_seen_secs = last_seen_msecs / 1000;
- seq_printf(seq, " * %15pI4 %14pM %6i:%02i\n",
- &dat_entry->ip, dat_entry->mac_addr,
- last_seen_mins, last_seen_secs);
+ switch (dat_entry->type) {
+ case BATADV_DAT_IPv4:
+ seq_printf(seq, " * %-40pI4 %15pM %6i:%02i\n",
+ dat_entry->ip, dat_entry->mac_addr,
+ last_seen_mins, last_seen_secs);
+ break;
+ case BATADV_DAT_IPv6:
+ seq_printf(seq, " * %-40pI6c %15pM %6i:%02i\n",
+ dat_entry->ip, dat_entry->mac_addr,
+ last_seen_mins, last_seen_secs);
+ break;
+ }
}
rcu_read_unlock();
}
@@ -836,9 +950,12 @@ bool batadv_dat_snoop_outgoing_arp_request(struct
batadv_priv *bat_priv,
hw_src = batadv_arp_hw_src(skb, 0);
ip_dst = batadv_arp_ip_dst(skb, 0);
- batadv_dat_entry_add(bat_priv, ip_src, hw_src);
+ batadv_dat_entry_add(bat_priv, (unsigned char *)&ip_src,
+ BATADV_DAT_IPv4, hw_src);
- dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_dst);
+ dat_entry = batadv_dat_entry_hash_find(bat_priv,
+ (unsigned char *)&ip_dst,
+ BATADV_DAT_IPv4);
if (dat_entry) {
skb_new = arp_create(ARPOP_REPLY, ETH_P_ARP, ip_src,
bat_priv->soft_iface, ip_dst, hw_src,
@@ -854,12 +971,14 @@ bool
batadv_dat_snoop_outgoing_arp_request(struct batadv_priv *bat_priv,
bat_priv->soft_iface->last_rx = jiffies;
netif_rx(skb_new);
- batadv_dbg(BATADV_DBG_DAT, bat_priv, "ARP request replied locally\n");
+ batadv_dbg(BATADV_DBG_DAT, bat_priv,
+ "ARP request replied locally\n");
ret = true;
} else {
/* Send the request on the DHT */
- ret = batadv_dat_send_data(bat_priv, skb, ip_dst,
- BATADV_P_DAT_DHT_GET);
+ ret = batadv_dat_send_data(bat_priv, skb,
+ (unsigned char *)&ip_dst, BATADV_DAT_IPv4,
+ BATADV_P_DAT_DHT_GET);
}
out:
if (dat_entry)
@@ -901,9 +1020,11 @@ bool
batadv_dat_snoop_incoming_arp_request(struct batadv_priv *bat_priv,
batadv_dbg_arp(bat_priv, skb, type, hdr_size,
"Parsing incoming ARP REQUEST");
- batadv_dat_entry_add(bat_priv, ip_src, hw_src);
+ batadv_dat_entry_add(bat_priv, (unsigned char *)&ip_src,
+ BATADV_DAT_IPv4, hw_src);
- dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_dst);
+ dat_entry = batadv_dat_entry_hash_find(bat_priv,
+ (unsigned char *)&ip_dst, BATADV_DAT_IPv4);
if (!dat_entry)
goto out;
@@ -963,14 +1084,18 @@ void batadv_dat_snoop_outgoing_arp_reply(struct
batadv_priv *bat_priv,
hw_dst = batadv_arp_hw_dst(skb, 0);
ip_dst = batadv_arp_ip_dst(skb, 0);
- batadv_dat_entry_add(bat_priv, ip_src, hw_src);
- batadv_dat_entry_add(bat_priv, ip_dst, hw_dst);
+ batadv_dat_entry_add(bat_priv, (unsigned char *)&ip_src,
+ BATADV_DAT_IPv4, hw_src);
+ batadv_dat_entry_add(bat_priv, (unsigned char *)&ip_dst,
+ BATADV_DAT_IPv4, hw_dst);
/* Send the ARP reply to the candidates for both the IP addresses that
* the node got within the ARP reply
*/
- batadv_dat_send_data(bat_priv, skb, ip_src, BATADV_P_DAT_DHT_PUT);
- batadv_dat_send_data(bat_priv, skb, ip_dst, BATADV_P_DAT_DHT_PUT);
+ batadv_dat_send_data(bat_priv, skb, (unsigned char *)&ip_src,
+ BATADV_DAT_IPv4, BATADV_P_DAT_DHT_PUT);
+ batadv_dat_send_data(bat_priv, skb, (unsigned char *)&ip_dst,
+ BATADV_DAT_IPv4, BATADV_P_DAT_DHT_PUT);
}
/**
* batadv_dat_snoop_incoming_arp_reply - snoop the ARP reply and fill the local
@@ -1005,8 +1130,10 @@ bool batadv_dat_snoop_incoming_arp_reply(struct
batadv_priv *bat_priv,
/* Update our internal cache with both the IP addresses the node got
* within the ARP reply
*/
- batadv_dat_entry_add(bat_priv, ip_src, hw_src);
- batadv_dat_entry_add(bat_priv, ip_dst, hw_dst);
+ batadv_dat_entry_add(bat_priv, (unsigned char *)&ip_src,
+ BATADV_DAT_IPv4, hw_src);
+ batadv_dat_entry_add(bat_priv, (unsigned char *)&ip_dst,
+ BATADV_DAT_IPv4, hw_dst);
/* if this REPLY is directed to a client of mine, let's deliver the
* packet to the interface
@@ -1050,7 +1177,8 @@ bool batadv_dat_drop_broadcast_packet(struct
batadv_priv *bat_priv,
goto out;
ip_dst = batadv_arp_ip_dst(forw_packet->skb, bcast_len);
- dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_dst);
+ dat_entry = batadv_dat_entry_hash_find(bat_priv,
+ (unsigned char *)&ip_dst, BATADV_DAT_IPv4);
/* check if the node already got this entry */
if (!dat_entry) {
batadv_dbg(BATADV_DBG_DAT, bat_priv,
diff --git a/types.h b/types.h
index aba8364..cbc4220 100644
--- a/types.h
+++ b/types.h
@@ -959,17 +959,18 @@ struct batadv_algo_ops {
};
/**
- * struct batadv_dat_entry - it is a single entry of batman-adv ARP backend. It
- * is used to stored ARP entries needed for the global DAT cache
- * @ip: the IPv4 corresponding to this DAT/ARP entry
- * @mac_addr: the MAC address associated to the stored IPv4
+ * struct batadv_dat_entry - it is a single entry of batman-adv
ARP/NDP backend. It
+ * is used to stored ARP/NDP entries needed for the global DAT cache
+ * @ip: the IPv4 / IPv6 corresponding to this DAT ARP/NDP entry
+ * @mac_addr: the MAC address associated to the stored @ip
* @last_update: time in jiffies when this entry was refreshed last time
* @hash_entry: hlist node for batadv_priv_dat::hash
* @refcount: number of contexts the object is used
* @rcu: struct used for freeing in an RCU-safe manner
*/
struct batadv_dat_entry {
- __be32 ip;
+ unsigned char *ip;
+ uint8_t type;
uint8_t mac_addr[ETH_ALEN];
unsigned long last_update;
struct hlist_node hash_entry;
@@ -978,6 +979,16 @@ struct batadv_dat_entry {
};
/**
+ * batadv_dat_types - types used in batadv_dat_entry for IP
+ * @BATADV_DAT_IPv4: IPv4 address type
+ * @BATADV_DAT_IPv6: IPv6 address type
+ */
+enum batadv_dat_types {
+ BATADV_DAT_IPv4,
+ BATADV_DAT_IPv6,
+};
+
+/**
* struct batadv_dat_candidate - candidate destination for DAT operations
* @type: the type of the selected candidate. It can one of the following:
* - BATADV_DAT_CANDIDATE_NOT_FOUND
--
1.7.10.4
