linux/net/atm/mpoa_caches.c
Kees Cook 99a5e178bd ATM: use designated initializers
Prepare to mark sensitive kernel structures for randomization by making
sure they're using designated initializers. These were identified during
allyesconfig builds of x86, arm, and arm64, with most initializer fixes
extracted from grsecurity.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-17 11:56:57 -05:00

569 lines
14 KiB
C

#include <linux/types.h>
#include <linux/atmmpc.h>
#include <linux/slab.h>
#include <linux/time.h>
#include "mpoa_caches.h"
#include "mpc.h"
/*
* mpoa_caches.c: Implementation of ingress and egress cache
* handling functions
*/
#if 0
#define dprintk(format, args...) \
printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args) /* debug */
#else
#define dprintk(format, args...) \
do { if (0) \
printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args);\
} while (0)
#endif
#if 0
#define ddprintk(format, args...) \
printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args) /* debug */
#else
#define ddprintk(format, args...) \
do { if (0) \
printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args);\
} while (0)
#endif
static in_cache_entry *in_cache_get(__be32 dst_ip,
struct mpoa_client *client)
{
in_cache_entry *entry;
read_lock_bh(&client->ingress_lock);
entry = client->in_cache;
while (entry != NULL) {
if (entry->ctrl_info.in_dst_ip == dst_ip) {
atomic_inc(&entry->use);
read_unlock_bh(&client->ingress_lock);
return entry;
}
entry = entry->next;
}
read_unlock_bh(&client->ingress_lock);
return NULL;
}
static in_cache_entry *in_cache_get_with_mask(__be32 dst_ip,
struct mpoa_client *client,
__be32 mask)
{
in_cache_entry *entry;
read_lock_bh(&client->ingress_lock);
entry = client->in_cache;
while (entry != NULL) {
if ((entry->ctrl_info.in_dst_ip & mask) == (dst_ip & mask)) {
atomic_inc(&entry->use);
read_unlock_bh(&client->ingress_lock);
return entry;
}
entry = entry->next;
}
read_unlock_bh(&client->ingress_lock);
return NULL;
}
static in_cache_entry *in_cache_get_by_vcc(struct atm_vcc *vcc,
struct mpoa_client *client)
{
in_cache_entry *entry;
read_lock_bh(&client->ingress_lock);
entry = client->in_cache;
while (entry != NULL) {
if (entry->shortcut == vcc) {
atomic_inc(&entry->use);
read_unlock_bh(&client->ingress_lock);
return entry;
}
entry = entry->next;
}
read_unlock_bh(&client->ingress_lock);
return NULL;
}
static in_cache_entry *in_cache_add_entry(__be32 dst_ip,
struct mpoa_client *client)
{
in_cache_entry *entry = kzalloc(sizeof(in_cache_entry), GFP_KERNEL);
if (entry == NULL) {
pr_info("mpoa: mpoa_caches.c: new_in_cache_entry: out of memory\n");
return NULL;
}
dprintk("adding an ingress entry, ip = %pI4\n", &dst_ip);
atomic_set(&entry->use, 1);
dprintk("new_in_cache_entry: about to lock\n");
write_lock_bh(&client->ingress_lock);
entry->next = client->in_cache;
entry->prev = NULL;
if (client->in_cache != NULL)
client->in_cache->prev = entry;
client->in_cache = entry;
memcpy(entry->MPS_ctrl_ATM_addr, client->mps_ctrl_addr, ATM_ESA_LEN);
entry->ctrl_info.in_dst_ip = dst_ip;
do_gettimeofday(&(entry->tv));
entry->retry_time = client->parameters.mpc_p4;
entry->count = 1;
entry->entry_state = INGRESS_INVALID;
entry->ctrl_info.holding_time = HOLDING_TIME_DEFAULT;
atomic_inc(&entry->use);
write_unlock_bh(&client->ingress_lock);
dprintk("new_in_cache_entry: unlocked\n");
return entry;
}
static int cache_hit(in_cache_entry *entry, struct mpoa_client *mpc)
{
struct atm_mpoa_qos *qos;
struct k_message msg;
entry->count++;
if (entry->entry_state == INGRESS_RESOLVED && entry->shortcut != NULL)
return OPEN;
if (entry->entry_state == INGRESS_REFRESHING) {
if (entry->count > mpc->parameters.mpc_p1) {
msg.type = SND_MPOA_RES_RQST;
msg.content.in_info = entry->ctrl_info;
memcpy(msg.MPS_ctrl, mpc->mps_ctrl_addr, ATM_ESA_LEN);
qos = atm_mpoa_search_qos(entry->ctrl_info.in_dst_ip);
if (qos != NULL)
msg.qos = qos->qos;
msg_to_mpoad(&msg, mpc);
do_gettimeofday(&(entry->reply_wait));
entry->entry_state = INGRESS_RESOLVING;
}
if (entry->shortcut != NULL)
return OPEN;
return CLOSED;
}
if (entry->entry_state == INGRESS_RESOLVING && entry->shortcut != NULL)
return OPEN;
if (entry->count > mpc->parameters.mpc_p1 &&
entry->entry_state == INGRESS_INVALID) {
dprintk("(%s) threshold exceeded for ip %pI4, sending MPOA res req\n",
mpc->dev->name, &entry->ctrl_info.in_dst_ip);
entry->entry_state = INGRESS_RESOLVING;
msg.type = SND_MPOA_RES_RQST;
memcpy(msg.MPS_ctrl, mpc->mps_ctrl_addr, ATM_ESA_LEN);
msg.content.in_info = entry->ctrl_info;
qos = atm_mpoa_search_qos(entry->ctrl_info.in_dst_ip);
if (qos != NULL)
msg.qos = qos->qos;
msg_to_mpoad(&msg, mpc);
do_gettimeofday(&(entry->reply_wait));
}
return CLOSED;
}
static void in_cache_put(in_cache_entry *entry)
{
if (atomic_dec_and_test(&entry->use)) {
memset(entry, 0, sizeof(in_cache_entry));
kfree(entry);
}
}
/*
* This should be called with write lock on
*/
static void in_cache_remove_entry(in_cache_entry *entry,
struct mpoa_client *client)
{
struct atm_vcc *vcc;
struct k_message msg;
vcc = entry->shortcut;
dprintk("removing an ingress entry, ip = %pI4\n",
&entry->ctrl_info.in_dst_ip);
if (entry->prev != NULL)
entry->prev->next = entry->next;
else
client->in_cache = entry->next;
if (entry->next != NULL)
entry->next->prev = entry->prev;
client->in_ops->put(entry);
if (client->in_cache == NULL && client->eg_cache == NULL) {
msg.type = STOP_KEEP_ALIVE_SM;
msg_to_mpoad(&msg, client);
}
/* Check if the egress side still uses this VCC */
if (vcc != NULL) {
eg_cache_entry *eg_entry = client->eg_ops->get_by_vcc(vcc,
client);
if (eg_entry != NULL) {
client->eg_ops->put(eg_entry);
return;
}
vcc_release_async(vcc, -EPIPE);
}
}
/* Call this every MPC-p2 seconds... Not exactly correct solution,
but an easy one... */
static void clear_count_and_expired(struct mpoa_client *client)
{
in_cache_entry *entry, *next_entry;
struct timeval now;
do_gettimeofday(&now);
write_lock_bh(&client->ingress_lock);
entry = client->in_cache;
while (entry != NULL) {
entry->count = 0;
next_entry = entry->next;
if ((now.tv_sec - entry->tv.tv_sec)
> entry->ctrl_info.holding_time) {
dprintk("holding time expired, ip = %pI4\n",
&entry->ctrl_info.in_dst_ip);
client->in_ops->remove_entry(entry, client);
}
entry = next_entry;
}
write_unlock_bh(&client->ingress_lock);
}
/* Call this every MPC-p4 seconds. */
static void check_resolving_entries(struct mpoa_client *client)
{
struct atm_mpoa_qos *qos;
in_cache_entry *entry;
struct timeval now;
struct k_message msg;
do_gettimeofday(&now);
read_lock_bh(&client->ingress_lock);
entry = client->in_cache;
while (entry != NULL) {
if (entry->entry_state == INGRESS_RESOLVING) {
if ((now.tv_sec - entry->hold_down.tv_sec) <
client->parameters.mpc_p6) {
entry = entry->next; /* Entry in hold down */
continue;
}
if ((now.tv_sec - entry->reply_wait.tv_sec) >
entry->retry_time) {
entry->retry_time = MPC_C1 * (entry->retry_time);
/*
* Retry time maximum exceeded,
* put entry in hold down.
*/
if (entry->retry_time > client->parameters.mpc_p5) {
do_gettimeofday(&(entry->hold_down));
entry->retry_time = client->parameters.mpc_p4;
entry = entry->next;
continue;
}
/* Ask daemon to send a resolution request. */
memset(&(entry->hold_down), 0, sizeof(struct timeval));
msg.type = SND_MPOA_RES_RTRY;
memcpy(msg.MPS_ctrl, client->mps_ctrl_addr, ATM_ESA_LEN);
msg.content.in_info = entry->ctrl_info;
qos = atm_mpoa_search_qos(entry->ctrl_info.in_dst_ip);
if (qos != NULL)
msg.qos = qos->qos;
msg_to_mpoad(&msg, client);
do_gettimeofday(&(entry->reply_wait));
}
}
entry = entry->next;
}
read_unlock_bh(&client->ingress_lock);
}
/* Call this every MPC-p5 seconds. */
static void refresh_entries(struct mpoa_client *client)
{
struct timeval now;
struct in_cache_entry *entry = client->in_cache;
ddprintk("refresh_entries\n");
do_gettimeofday(&now);
read_lock_bh(&client->ingress_lock);
while (entry != NULL) {
if (entry->entry_state == INGRESS_RESOLVED) {
if (!(entry->refresh_time))
entry->refresh_time = (2 * (entry->ctrl_info.holding_time))/3;
if ((now.tv_sec - entry->reply_wait.tv_sec) >
entry->refresh_time) {
dprintk("refreshing an entry.\n");
entry->entry_state = INGRESS_REFRESHING;
}
}
entry = entry->next;
}
read_unlock_bh(&client->ingress_lock);
}
static void in_destroy_cache(struct mpoa_client *mpc)
{
write_lock_irq(&mpc->ingress_lock);
while (mpc->in_cache != NULL)
mpc->in_ops->remove_entry(mpc->in_cache, mpc);
write_unlock_irq(&mpc->ingress_lock);
}
static eg_cache_entry *eg_cache_get_by_cache_id(__be32 cache_id,
struct mpoa_client *mpc)
{
eg_cache_entry *entry;
read_lock_irq(&mpc->egress_lock);
entry = mpc->eg_cache;
while (entry != NULL) {
if (entry->ctrl_info.cache_id == cache_id) {
atomic_inc(&entry->use);
read_unlock_irq(&mpc->egress_lock);
return entry;
}
entry = entry->next;
}
read_unlock_irq(&mpc->egress_lock);
return NULL;
}
/* This can be called from any context since it saves CPU flags */
static eg_cache_entry *eg_cache_get_by_tag(__be32 tag, struct mpoa_client *mpc)
{
unsigned long flags;
eg_cache_entry *entry;
read_lock_irqsave(&mpc->egress_lock, flags);
entry = mpc->eg_cache;
while (entry != NULL) {
if (entry->ctrl_info.tag == tag) {
atomic_inc(&entry->use);
read_unlock_irqrestore(&mpc->egress_lock, flags);
return entry;
}
entry = entry->next;
}
read_unlock_irqrestore(&mpc->egress_lock, flags);
return NULL;
}
/* This can be called from any context since it saves CPU flags */
static eg_cache_entry *eg_cache_get_by_vcc(struct atm_vcc *vcc,
struct mpoa_client *mpc)
{
unsigned long flags;
eg_cache_entry *entry;
read_lock_irqsave(&mpc->egress_lock, flags);
entry = mpc->eg_cache;
while (entry != NULL) {
if (entry->shortcut == vcc) {
atomic_inc(&entry->use);
read_unlock_irqrestore(&mpc->egress_lock, flags);
return entry;
}
entry = entry->next;
}
read_unlock_irqrestore(&mpc->egress_lock, flags);
return NULL;
}
static eg_cache_entry *eg_cache_get_by_src_ip(__be32 ipaddr,
struct mpoa_client *mpc)
{
eg_cache_entry *entry;
read_lock_irq(&mpc->egress_lock);
entry = mpc->eg_cache;
while (entry != NULL) {
if (entry->latest_ip_addr == ipaddr) {
atomic_inc(&entry->use);
read_unlock_irq(&mpc->egress_lock);
return entry;
}
entry = entry->next;
}
read_unlock_irq(&mpc->egress_lock);
return NULL;
}
static void eg_cache_put(eg_cache_entry *entry)
{
if (atomic_dec_and_test(&entry->use)) {
memset(entry, 0, sizeof(eg_cache_entry));
kfree(entry);
}
}
/*
* This should be called with write lock on
*/
static void eg_cache_remove_entry(eg_cache_entry *entry,
struct mpoa_client *client)
{
struct atm_vcc *vcc;
struct k_message msg;
vcc = entry->shortcut;
dprintk("removing an egress entry.\n");
if (entry->prev != NULL)
entry->prev->next = entry->next;
else
client->eg_cache = entry->next;
if (entry->next != NULL)
entry->next->prev = entry->prev;
client->eg_ops->put(entry);
if (client->in_cache == NULL && client->eg_cache == NULL) {
msg.type = STOP_KEEP_ALIVE_SM;
msg_to_mpoad(&msg, client);
}
/* Check if the ingress side still uses this VCC */
if (vcc != NULL) {
in_cache_entry *in_entry = client->in_ops->get_by_vcc(vcc, client);
if (in_entry != NULL) {
client->in_ops->put(in_entry);
return;
}
vcc_release_async(vcc, -EPIPE);
}
}
static eg_cache_entry *eg_cache_add_entry(struct k_message *msg,
struct mpoa_client *client)
{
eg_cache_entry *entry = kzalloc(sizeof(eg_cache_entry), GFP_KERNEL);
if (entry == NULL) {
pr_info("out of memory\n");
return NULL;
}
dprintk("adding an egress entry, ip = %pI4, this should be our IP\n",
&msg->content.eg_info.eg_dst_ip);
atomic_set(&entry->use, 1);
dprintk("new_eg_cache_entry: about to lock\n");
write_lock_irq(&client->egress_lock);
entry->next = client->eg_cache;
entry->prev = NULL;
if (client->eg_cache != NULL)
client->eg_cache->prev = entry;
client->eg_cache = entry;
memcpy(entry->MPS_ctrl_ATM_addr, client->mps_ctrl_addr, ATM_ESA_LEN);
entry->ctrl_info = msg->content.eg_info;
do_gettimeofday(&(entry->tv));
entry->entry_state = EGRESS_RESOLVED;
dprintk("new_eg_cache_entry cache_id %u\n",
ntohl(entry->ctrl_info.cache_id));
dprintk("mps_ip = %pI4\n", &entry->ctrl_info.mps_ip);
atomic_inc(&entry->use);
write_unlock_irq(&client->egress_lock);
dprintk("new_eg_cache_entry: unlocked\n");
return entry;
}
static void update_eg_cache_entry(eg_cache_entry *entry, uint16_t holding_time)
{
do_gettimeofday(&(entry->tv));
entry->entry_state = EGRESS_RESOLVED;
entry->ctrl_info.holding_time = holding_time;
}
static void clear_expired(struct mpoa_client *client)
{
eg_cache_entry *entry, *next_entry;
struct timeval now;
struct k_message msg;
do_gettimeofday(&now);
write_lock_irq(&client->egress_lock);
entry = client->eg_cache;
while (entry != NULL) {
next_entry = entry->next;
if ((now.tv_sec - entry->tv.tv_sec)
> entry->ctrl_info.holding_time) {
msg.type = SND_EGRESS_PURGE;
msg.content.eg_info = entry->ctrl_info;
dprintk("egress_cache: holding time expired, cache_id = %u.\n",
ntohl(entry->ctrl_info.cache_id));
msg_to_mpoad(&msg, client);
client->eg_ops->remove_entry(entry, client);
}
entry = next_entry;
}
write_unlock_irq(&client->egress_lock);
}
static void eg_destroy_cache(struct mpoa_client *mpc)
{
write_lock_irq(&mpc->egress_lock);
while (mpc->eg_cache != NULL)
mpc->eg_ops->remove_entry(mpc->eg_cache, mpc);
write_unlock_irq(&mpc->egress_lock);
}
static const struct in_cache_ops ingress_ops = {
.add_entry = in_cache_add_entry,
.get = in_cache_get,
.get_with_mask = in_cache_get_with_mask,
.get_by_vcc = in_cache_get_by_vcc,
.put = in_cache_put,
.remove_entry = in_cache_remove_entry,
.cache_hit = cache_hit,
.clear_count = clear_count_and_expired,
.check_resolving = check_resolving_entries,
.refresh = refresh_entries,
.destroy_cache = in_destroy_cache
};
static const struct eg_cache_ops egress_ops = {
.add_entry = eg_cache_add_entry,
.get_by_cache_id = eg_cache_get_by_cache_id,
.get_by_tag = eg_cache_get_by_tag,
.get_by_vcc = eg_cache_get_by_vcc,
.get_by_src_ip = eg_cache_get_by_src_ip,
.put = eg_cache_put,
.remove_entry = eg_cache_remove_entry,
.update = update_eg_cache_entry,
.clear_expired = clear_expired,
.destroy_cache = eg_destroy_cache
};
void atm_mpoa_init_cache(struct mpoa_client *mpc)
{
mpc->in_ops = &ingress_ops;
mpc->eg_ops = &egress_ops;
}