linux-sg2042/net/dccp/ccid.c

221 lines
5.2 KiB
C

/*
* net/dccp/ccid.c
*
* An implementation of the DCCP protocol
* Arnaldo Carvalho de Melo <acme@conectiva.com.br>
*
* CCID infrastructure
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include "ccid.h"
#include "ccids/lib/tfrc.h"
static struct ccid_operations *ccids[] = {
&ccid2_ops,
#ifdef CONFIG_IP_DCCP_CCID3
&ccid3_ops,
#endif
};
static struct ccid_operations *ccid_by_number(const u8 id)
{
int i;
for (i = 0; i < ARRAY_SIZE(ccids); i++)
if (ccids[i]->ccid_id == id)
return ccids[i];
return NULL;
}
/* check that up to @array_len members in @ccid_array are supported */
bool ccid_support_check(u8 const *ccid_array, u8 array_len)
{
while (array_len > 0)
if (ccid_by_number(ccid_array[--array_len]) == NULL)
return false;
return true;
}
/**
* ccid_get_builtin_ccids - Populate a list of built-in CCIDs
* @ccid_array: pointer to copy into
* @array_len: value to return length into
* This function allocates memory - caller must see that it is freed after use.
*/
int ccid_get_builtin_ccids(u8 **ccid_array, u8 *array_len)
{
*ccid_array = kmalloc(ARRAY_SIZE(ccids), gfp_any());
if (*ccid_array == NULL)
return -ENOBUFS;
for (*array_len = 0; *array_len < ARRAY_SIZE(ccids); *array_len += 1)
(*ccid_array)[*array_len] = ccids[*array_len]->ccid_id;
return 0;
}
int ccid_getsockopt_builtin_ccids(struct sock *sk, int len,
char __user *optval, int __user *optlen)
{
u8 *ccid_array, array_len;
int err = 0;
if (ccid_get_builtin_ccids(&ccid_array, &array_len))
return -ENOBUFS;
if (put_user(array_len, optlen))
err = -EFAULT;
else if (len > 0 && copy_to_user(optval, ccid_array,
len > array_len ? array_len : len))
err = -EFAULT;
kfree(ccid_array);
return err;
}
static struct kmem_cache *ccid_kmem_cache_create(int obj_size, char *slab_name_fmt, const char *fmt,...)
{
struct kmem_cache *slab;
va_list args;
va_start(args, fmt);
vsnprintf(slab_name_fmt, CCID_SLAB_NAME_LENGTH, fmt, args);
va_end(args);
slab = kmem_cache_create(slab_name_fmt, sizeof(struct ccid) + obj_size, 0,
SLAB_HWCACHE_ALIGN, NULL);
return slab;
}
static void ccid_kmem_cache_destroy(struct kmem_cache *slab)
{
if (slab != NULL)
kmem_cache_destroy(slab);
}
static int ccid_activate(struct ccid_operations *ccid_ops)
{
int err = -ENOBUFS;
ccid_ops->ccid_hc_rx_slab =
ccid_kmem_cache_create(ccid_ops->ccid_hc_rx_obj_size,
ccid_ops->ccid_hc_rx_slab_name,
"ccid%u_hc_rx_sock",
ccid_ops->ccid_id);
if (ccid_ops->ccid_hc_rx_slab == NULL)
goto out;
ccid_ops->ccid_hc_tx_slab =
ccid_kmem_cache_create(ccid_ops->ccid_hc_tx_obj_size,
ccid_ops->ccid_hc_tx_slab_name,
"ccid%u_hc_tx_sock",
ccid_ops->ccid_id);
if (ccid_ops->ccid_hc_tx_slab == NULL)
goto out_free_rx_slab;
pr_info("CCID: Activated CCID %d (%s)\n",
ccid_ops->ccid_id, ccid_ops->ccid_name);
err = 0;
out:
return err;
out_free_rx_slab:
ccid_kmem_cache_destroy(ccid_ops->ccid_hc_rx_slab);
ccid_ops->ccid_hc_rx_slab = NULL;
goto out;
}
static void ccid_deactivate(struct ccid_operations *ccid_ops)
{
ccid_kmem_cache_destroy(ccid_ops->ccid_hc_tx_slab);
ccid_ops->ccid_hc_tx_slab = NULL;
ccid_kmem_cache_destroy(ccid_ops->ccid_hc_rx_slab);
ccid_ops->ccid_hc_rx_slab = NULL;
pr_info("CCID: Deactivated CCID %d (%s)\n",
ccid_ops->ccid_id, ccid_ops->ccid_name);
}
struct ccid *ccid_new(const u8 id, struct sock *sk, bool rx)
{
struct ccid_operations *ccid_ops = ccid_by_number(id);
struct ccid *ccid = NULL;
if (ccid_ops == NULL)
goto out;
ccid = kmem_cache_alloc(rx ? ccid_ops->ccid_hc_rx_slab :
ccid_ops->ccid_hc_tx_slab, gfp_any());
if (ccid == NULL)
goto out;
ccid->ccid_ops = ccid_ops;
if (rx) {
memset(ccid + 1, 0, ccid_ops->ccid_hc_rx_obj_size);
if (ccid->ccid_ops->ccid_hc_rx_init != NULL &&
ccid->ccid_ops->ccid_hc_rx_init(ccid, sk) != 0)
goto out_free_ccid;
} else {
memset(ccid + 1, 0, ccid_ops->ccid_hc_tx_obj_size);
if (ccid->ccid_ops->ccid_hc_tx_init != NULL &&
ccid->ccid_ops->ccid_hc_tx_init(ccid, sk) != 0)
goto out_free_ccid;
}
out:
return ccid;
out_free_ccid:
kmem_cache_free(rx ? ccid_ops->ccid_hc_rx_slab :
ccid_ops->ccid_hc_tx_slab, ccid);
ccid = NULL;
goto out;
}
void ccid_hc_rx_delete(struct ccid *ccid, struct sock *sk)
{
if (ccid != NULL) {
if (ccid->ccid_ops->ccid_hc_rx_exit != NULL)
ccid->ccid_ops->ccid_hc_rx_exit(sk);
kmem_cache_free(ccid->ccid_ops->ccid_hc_rx_slab, ccid);
}
}
void ccid_hc_tx_delete(struct ccid *ccid, struct sock *sk)
{
if (ccid != NULL) {
if (ccid->ccid_ops->ccid_hc_tx_exit != NULL)
ccid->ccid_ops->ccid_hc_tx_exit(sk);
kmem_cache_free(ccid->ccid_ops->ccid_hc_tx_slab, ccid);
}
}
int __init ccid_initialize_builtins(void)
{
int i, err = tfrc_lib_init();
if (err)
return err;
for (i = 0; i < ARRAY_SIZE(ccids); i++) {
err = ccid_activate(ccids[i]);
if (err)
goto unwind_registrations;
}
return 0;
unwind_registrations:
while(--i >= 0)
ccid_deactivate(ccids[i]);
tfrc_lib_exit();
return err;
}
void ccid_cleanup_builtins(void)
{
int i;
for (i = 0; i < ARRAY_SIZE(ccids); i++)
ccid_deactivate(ccids[i]);
tfrc_lib_exit();
}