xfrm: configure policy hash table thresholds by netlink

Enable to specify local and remote prefix length thresholds for the
policy hash table via a netlink XFRM_MSG_NEWSPDINFO message.

prefix length thresholds are specified by XFRMA_SPD_IPV4_HTHRESH and
XFRMA_SPD_IPV6_HTHRESH optional attributes (struct xfrmu_spdhthresh).

example:

    struct xfrmu_spdhthresh thresh4 = {
        .lbits = 0;
        .rbits = 24;
    };
    struct xfrmu_spdhthresh thresh6 = {
        .lbits = 0;
        .rbits = 56;
    };
    struct nlmsghdr *hdr;
    struct nl_msg *msg;

    msg = nlmsg_alloc();
    hdr = nlmsg_put(msg, NL_AUTO_PORT, NL_AUTO_SEQ, XFRMA_SPD_IPV4_HTHRESH, sizeof(__u32), NLM_F_REQUEST);
    nla_put(msg, XFRMA_SPD_IPV4_HTHRESH, sizeof(thresh4), &thresh4);
    nla_put(msg, XFRMA_SPD_IPV6_HTHRESH, sizeof(thresh6), &thresh6);
    nla_send_auto(sk, msg);

The numbers are the policy selector minimum prefix lengths to put a
policy in the hash table.

- lbits is the local threshold (source address for out policies,
  destination address for in and fwd policies).

- rbits is the remote threshold (destination address for out
  policies, source address for in and fwd policies).

The default values are:

XFRMA_SPD_IPV4_HTHRESH: 32 32
XFRMA_SPD_IPV6_HTHRESH: 128 128

Dynamic re-building of the SPD is performed when the thresholds values
are changed.

The current thresholds can be read via a XFRM_MSG_GETSPDINFO request:
the kernel replies to XFRM_MSG_GETSPDINFO requests by an
XFRM_MSG_NEWSPDINFO message, with both attributes
XFRMA_SPD_IPV4_HTHRESH and XFRMA_SPD_IPV6_HTHRESH.

Signed-off-by: Christophe Gouault <christophe.gouault@6wind.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
This commit is contained in:
Christophe Gouault 2014-08-29 16:16:05 +02:00 committed by Steffen Klassert
parent b58555f176
commit 880a6fab8f
5 changed files with 182 additions and 3 deletions

View file

@ -19,6 +19,15 @@ struct xfrm_policy_hash {
u8 sbits6;
};
struct xfrm_policy_hthresh {
struct work_struct work;
seqlock_t lock;
u8 lbits4;
u8 rbits4;
u8 lbits6;
u8 rbits6;
};
struct netns_xfrm {
struct list_head state_all;
/*
@ -45,6 +54,7 @@ struct netns_xfrm {
struct xfrm_policy_hash policy_bydst[XFRM_POLICY_MAX * 2];
unsigned int policy_count[XFRM_POLICY_MAX * 2];
struct work_struct policy_hash_work;
struct xfrm_policy_hthresh policy_hthresh;
struct sock *nlsk;

View file

@ -1591,6 +1591,7 @@ struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark,
struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8, int dir,
u32 id, int delete, int *err);
int xfrm_policy_flush(struct net *net, u8 type, bool task_valid);
void xfrm_policy_hash_rebuild(struct net *net);
u32 xfrm_get_acqseq(void);
int verify_spi_info(u8 proto, u32 min, u32 max);
int xfrm_alloc_spi(struct xfrm_state *x, u32 minspi, u32 maxspi);

View file

@ -328,6 +328,8 @@ enum xfrm_spdattr_type_t {
XFRMA_SPD_UNSPEC,
XFRMA_SPD_INFO,
XFRMA_SPD_HINFO,
XFRMA_SPD_IPV4_HTHRESH,
XFRMA_SPD_IPV6_HTHRESH,
__XFRMA_SPD_MAX
#define XFRMA_SPD_MAX (__XFRMA_SPD_MAX - 1)
@ -347,6 +349,11 @@ struct xfrmu_spdhinfo {
__u32 spdhmcnt;
};
struct xfrmu_spdhthresh {
__u8 lbits;
__u8 rbits;
};
struct xfrm_usersa_info {
struct xfrm_selector sel;
struct xfrm_id id;

View file

@ -566,6 +566,86 @@ static void xfrm_hash_resize(struct work_struct *work)
mutex_unlock(&hash_resize_mutex);
}
static void xfrm_hash_rebuild(struct work_struct *work)
{
struct net *net = container_of(work, struct net,
xfrm.policy_hthresh.work);
unsigned int hmask;
struct xfrm_policy *pol;
struct xfrm_policy *policy;
struct hlist_head *chain;
struct hlist_head *odst;
struct hlist_node *newpos;
int i;
int dir;
unsigned seq;
u8 lbits4, rbits4, lbits6, rbits6;
mutex_lock(&hash_resize_mutex);
/* read selector prefixlen thresholds */
do {
seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
lbits4 = net->xfrm.policy_hthresh.lbits4;
rbits4 = net->xfrm.policy_hthresh.rbits4;
lbits6 = net->xfrm.policy_hthresh.lbits6;
rbits6 = net->xfrm.policy_hthresh.rbits6;
} while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
write_lock_bh(&net->xfrm.xfrm_policy_lock);
/* reset the bydst and inexact table in all directions */
for (dir = 0; dir < XFRM_POLICY_MAX * 2; dir++) {
INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
hmask = net->xfrm.policy_bydst[dir].hmask;
odst = net->xfrm.policy_bydst[dir].table;
for (i = hmask; i >= 0; i--)
INIT_HLIST_HEAD(odst + i);
if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
/* dir out => dst = remote, src = local */
net->xfrm.policy_bydst[dir].dbits4 = rbits4;
net->xfrm.policy_bydst[dir].sbits4 = lbits4;
net->xfrm.policy_bydst[dir].dbits6 = rbits6;
net->xfrm.policy_bydst[dir].sbits6 = lbits6;
} else {
/* dir in/fwd => dst = local, src = remote */
net->xfrm.policy_bydst[dir].dbits4 = lbits4;
net->xfrm.policy_bydst[dir].sbits4 = rbits4;
net->xfrm.policy_bydst[dir].dbits6 = lbits6;
net->xfrm.policy_bydst[dir].sbits6 = rbits6;
}
}
/* re-insert all policies by order of creation */
list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
newpos = NULL;
chain = policy_hash_bysel(net, &policy->selector,
policy->family,
xfrm_policy_id2dir(policy->index));
hlist_for_each_entry(pol, chain, bydst) {
if (policy->priority >= pol->priority)
newpos = &pol->bydst;
else
break;
}
if (newpos)
hlist_add_behind(&policy->bydst, newpos);
else
hlist_add_head(&policy->bydst, chain);
}
write_unlock_bh(&net->xfrm.xfrm_policy_lock);
mutex_unlock(&hash_resize_mutex);
}
void xfrm_policy_hash_rebuild(struct net *net)
{
schedule_work(&net->xfrm.policy_hthresh.work);
}
EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
/* Generate new index... KAME seems to generate them ordered by cost
* of an absolute inpredictability of ordering of rules. This will not pass. */
static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
@ -2872,9 +2952,16 @@ static int __net_init xfrm_policy_init(struct net *net)
htab->dbits6 = 128;
htab->sbits6 = 128;
}
net->xfrm.policy_hthresh.lbits4 = 32;
net->xfrm.policy_hthresh.rbits4 = 32;
net->xfrm.policy_hthresh.lbits6 = 128;
net->xfrm.policy_hthresh.rbits6 = 128;
seqlock_init(&net->xfrm.policy_hthresh.lock);
INIT_LIST_HEAD(&net->xfrm.policy_all);
INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
if (net_eq(net, &init_net))
register_netdevice_notifier(&xfrm_dev_notifier);
return 0;

View file

@ -964,7 +964,9 @@ static inline size_t xfrm_spdinfo_msgsize(void)
{
return NLMSG_ALIGN(4)
+ nla_total_size(sizeof(struct xfrmu_spdinfo))
+ nla_total_size(sizeof(struct xfrmu_spdhinfo));
+ nla_total_size(sizeof(struct xfrmu_spdhinfo))
+ nla_total_size(sizeof(struct xfrmu_spdhthresh))
+ nla_total_size(sizeof(struct xfrmu_spdhthresh));
}
static int build_spdinfo(struct sk_buff *skb, struct net *net,
@ -973,9 +975,11 @@ static int build_spdinfo(struct sk_buff *skb, struct net *net,
struct xfrmk_spdinfo si;
struct xfrmu_spdinfo spc;
struct xfrmu_spdhinfo sph;
struct xfrmu_spdhthresh spt4, spt6;
struct nlmsghdr *nlh;
int err;
u32 *f;
unsigned lseq;
nlh = nlmsg_put(skb, portid, seq, XFRM_MSG_NEWSPDINFO, sizeof(u32), 0);
if (nlh == NULL) /* shouldn't really happen ... */
@ -993,9 +997,22 @@ static int build_spdinfo(struct sk_buff *skb, struct net *net,
sph.spdhcnt = si.spdhcnt;
sph.spdhmcnt = si.spdhmcnt;
do {
lseq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
spt4.lbits = net->xfrm.policy_hthresh.lbits4;
spt4.rbits = net->xfrm.policy_hthresh.rbits4;
spt6.lbits = net->xfrm.policy_hthresh.lbits6;
spt6.rbits = net->xfrm.policy_hthresh.rbits6;
} while (read_seqretry(&net->xfrm.policy_hthresh.lock, lseq));
err = nla_put(skb, XFRMA_SPD_INFO, sizeof(spc), &spc);
if (!err)
err = nla_put(skb, XFRMA_SPD_HINFO, sizeof(sph), &sph);
if (!err)
err = nla_put(skb, XFRMA_SPD_IPV4_HTHRESH, sizeof(spt4), &spt4);
if (!err)
err = nla_put(skb, XFRMA_SPD_IPV6_HTHRESH, sizeof(spt6), &spt6);
if (err) {
nlmsg_cancel(skb, nlh);
return err;
@ -1004,6 +1021,51 @@ static int build_spdinfo(struct sk_buff *skb, struct net *net,
return nlmsg_end(skb, nlh);
}
static int xfrm_set_spdinfo(struct sk_buff *skb, struct nlmsghdr *nlh,
struct nlattr **attrs)
{
struct net *net = sock_net(skb->sk);
struct xfrmu_spdhthresh *thresh4 = NULL;
struct xfrmu_spdhthresh *thresh6 = NULL;
/* selector prefixlen thresholds to hash policies */
if (attrs[XFRMA_SPD_IPV4_HTHRESH]) {
struct nlattr *rta = attrs[XFRMA_SPD_IPV4_HTHRESH];
if (nla_len(rta) < sizeof(*thresh4))
return -EINVAL;
thresh4 = nla_data(rta);
if (thresh4->lbits > 32 || thresh4->rbits > 32)
return -EINVAL;
}
if (attrs[XFRMA_SPD_IPV6_HTHRESH]) {
struct nlattr *rta = attrs[XFRMA_SPD_IPV6_HTHRESH];
if (nla_len(rta) < sizeof(*thresh6))
return -EINVAL;
thresh6 = nla_data(rta);
if (thresh6->lbits > 128 || thresh6->rbits > 128)
return -EINVAL;
}
if (thresh4 || thresh6) {
write_seqlock(&net->xfrm.policy_hthresh.lock);
if (thresh4) {
net->xfrm.policy_hthresh.lbits4 = thresh4->lbits;
net->xfrm.policy_hthresh.rbits4 = thresh4->rbits;
}
if (thresh6) {
net->xfrm.policy_hthresh.lbits6 = thresh6->lbits;
net->xfrm.policy_hthresh.rbits6 = thresh6->rbits;
}
write_sequnlock(&net->xfrm.policy_hthresh.lock);
xfrm_policy_hash_rebuild(net);
}
return 0;
}
static int xfrm_get_spdinfo(struct sk_buff *skb, struct nlmsghdr *nlh,
struct nlattr **attrs)
{
@ -2274,6 +2336,7 @@ static const int xfrm_msg_min[XFRM_NR_MSGTYPES] = {
[XFRM_MSG_REPORT - XFRM_MSG_BASE] = XMSGSIZE(xfrm_user_report),
[XFRM_MSG_MIGRATE - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userpolicy_id),
[XFRM_MSG_GETSADINFO - XFRM_MSG_BASE] = sizeof(u32),
[XFRM_MSG_NEWSPDINFO - XFRM_MSG_BASE] = sizeof(u32),
[XFRM_MSG_GETSPDINFO - XFRM_MSG_BASE] = sizeof(u32),
};
@ -2308,10 +2371,17 @@ static const struct nla_policy xfrma_policy[XFRMA_MAX+1] = {
[XFRMA_ADDRESS_FILTER] = { .len = sizeof(struct xfrm_address_filter) },
};
static const struct nla_policy xfrma_spd_policy[XFRMA_SPD_MAX+1] = {
[XFRMA_SPD_IPV4_HTHRESH] = { .len = sizeof(struct xfrmu_spdhthresh) },
[XFRMA_SPD_IPV6_HTHRESH] = { .len = sizeof(struct xfrmu_spdhthresh) },
};
static const struct xfrm_link {
int (*doit)(struct sk_buff *, struct nlmsghdr *, struct nlattr **);
int (*dump)(struct sk_buff *, struct netlink_callback *);
int (*done)(struct netlink_callback *);
const struct nla_policy *nla_pol;
int nla_max;
} xfrm_dispatch[XFRM_NR_MSGTYPES] = {
[XFRM_MSG_NEWSA - XFRM_MSG_BASE] = { .doit = xfrm_add_sa },
[XFRM_MSG_DELSA - XFRM_MSG_BASE] = { .doit = xfrm_del_sa },
@ -2335,6 +2405,9 @@ static const struct xfrm_link {
[XFRM_MSG_GETAE - XFRM_MSG_BASE] = { .doit = xfrm_get_ae },
[XFRM_MSG_MIGRATE - XFRM_MSG_BASE] = { .doit = xfrm_do_migrate },
[XFRM_MSG_GETSADINFO - XFRM_MSG_BASE] = { .doit = xfrm_get_sadinfo },
[XFRM_MSG_NEWSPDINFO - XFRM_MSG_BASE] = { .doit = xfrm_set_spdinfo,
.nla_pol = xfrma_spd_policy,
.nla_max = XFRMA_SPD_MAX },
[XFRM_MSG_GETSPDINFO - XFRM_MSG_BASE] = { .doit = xfrm_get_spdinfo },
};
@ -2371,8 +2444,9 @@ static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
}
}
err = nlmsg_parse(nlh, xfrm_msg_min[type], attrs, XFRMA_MAX,
xfrma_policy);
err = nlmsg_parse(nlh, xfrm_msg_min[type], attrs,
link->nla_max ? : XFRMA_MAX,
link->nla_pol ? : xfrma_policy);
if (err < 0)
return err;