diff options
Diffstat (limited to 'net/dccp/ccid.c')
| -rw-r--r-- | net/dccp/ccid.c | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/net/dccp/ccid.c b/net/dccp/ccid.c new file mode 100644 index 000000000..6beac5d34 --- /dev/null +++ b/net/dccp/ccid.c @@ -0,0 +1,219 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * net/dccp/ccid.c + * + * An implementation of the DCCP protocol + * Arnaldo Carvalho de Melo <acme@conectiva.com.br> + * + * CCID infrastructure + */ + +#include <linux/slab.h> + +#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 __printf(3, 4) 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) +{ + kmem_cache_destroy(slab); +} + +static int __init 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("DCCP: 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("DCCP: 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(); +} |