e2e9b6541d
This work extends the "classic" BPF programmable tc classifier by
extending its scope also to native eBPF code!
This allows for user space to implement own custom, 'safe' C like
classifiers (or whatever other frontend language LLVM et al may
provide in future), that can then be compiled with the LLVM eBPF
backend to an eBPF elf file. The result of this can be loaded into
the kernel via iproute2's tc. In the kernel, they can be JITed on
major archs and thus run in native performance.
Simple, minimal toy example to demonstrate the workflow:
#include <linux/ip.h>
#include <linux/if_ether.h>
#include <linux/bpf.h>
#include "tc_bpf_api.h"
__section("classify")
int cls_main(struct sk_buff *skb)
{
return (0x800 << 16) | load_byte(skb, ETH_HLEN + __builtin_offsetof(struct iphdr, tos));
}
char __license[] __section("license") = "GPL";
The classifier can then be compiled into eBPF opcodes and loaded
via tc, for example:
clang -O2 -emit-llvm -c cls.c -o - | llc -march=bpf -filetype=obj -o cls.o
tc filter add dev em1 parent 1: bpf cls.o [...]
As it has been demonstrated, the scope can even reach up to a fully
fledged flow dissector (similarly as in samples/bpf/sockex2_kern.c).
For tc, maps are allowed to be used, but from kernel context only,
in other words, eBPF code can keep state across filter invocations.
In future, we perhaps may reattach from a different application to
those maps e.g., to read out collected statistics/state.
Similarly as in socket filters, we may extend functionality for eBPF
classifiers over time depending on the use cases. For that purpose,
cls_bpf programs are using BPF_PROG_TYPE_SCHED_CLS program type, so
we can allow additional functions/accessors (e.g. an ABI compatible
offset translation to skb fields/metadata). For an initial cls_bpf
support, we allow the same set of helper functions as eBPF socket
filters, but we could diverge at some point in time w/o problem.
I was wondering whether cls_bpf and act_bpf could share C programs,
I can imagine that at some point, we introduce i) further common
handlers for both (or even beyond their scope), and/or if truly needed
ii) some restricted function space for each of them. Both can be
abstracted easily through struct bpf_verifier_ops in future.
The context of cls_bpf versus act_bpf is slightly different though:
a cls_bpf program will return a specific classid whereas act_bpf a
drop/non-drop return code, latter may also in future mangle skbs.
That said, we can surely have a "classify" and "action" section in
a single object file, or considered mentioned constraint add a
possibility of a shared section.
The workflow for getting native eBPF running from tc [1] is as
follows: for f_bpf, I've added a slightly modified ELF parser code
from Alexei's kernel sample, which reads out the LLVM compiled
object, sets up maps (and dynamically fixes up map fds) if any, and
loads the eBPF instructions all centrally through the bpf syscall.
The resulting fd from the loaded program itself is being passed down
to cls_bpf, which looks up struct bpf_prog from the fd store, and
holds reference, so that it stays available also after tc program
lifetime. On tc filter destruction, it will then drop its reference.
Moreover, I've also added the optional possibility to annotate an
eBPF filter with a name (e.g. path to object file, or something
else if preferred) so that when tc dumps currently installed filters,
some more context can be given to an admin for a given instance (as
opposed to just the file descriptor number).
Last but not least, bpf_prog_get() and bpf_prog_put() needed to be
exported, so that eBPF can be used from cls_bpf built as a module.
Thanks to 60a3b2253c
("net: bpf: make eBPF interpreter images
read-only") I think this is of no concern since anything wanting to
alter eBPF opcode after verification stage would crash the kernel.
[1] http://git.breakpoint.cc/cgit/dborkman/iproute2.git/log/?h=ebpf
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
617 lines
13 KiB
C
617 lines
13 KiB
C
/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of version 2 of the GNU General Public
|
|
* License as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful, but
|
|
* WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* General Public License for more details.
|
|
*/
|
|
#include <linux/bpf.h>
|
|
#include <linux/syscalls.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/anon_inodes.h>
|
|
#include <linux/file.h>
|
|
#include <linux/license.h>
|
|
#include <linux/filter.h>
|
|
|
|
static LIST_HEAD(bpf_map_types);
|
|
|
|
static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
|
|
{
|
|
struct bpf_map_type_list *tl;
|
|
struct bpf_map *map;
|
|
|
|
list_for_each_entry(tl, &bpf_map_types, list_node) {
|
|
if (tl->type == attr->map_type) {
|
|
map = tl->ops->map_alloc(attr);
|
|
if (IS_ERR(map))
|
|
return map;
|
|
map->ops = tl->ops;
|
|
map->map_type = attr->map_type;
|
|
return map;
|
|
}
|
|
}
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
/* boot time registration of different map implementations */
|
|
void bpf_register_map_type(struct bpf_map_type_list *tl)
|
|
{
|
|
list_add(&tl->list_node, &bpf_map_types);
|
|
}
|
|
|
|
/* called from workqueue */
|
|
static void bpf_map_free_deferred(struct work_struct *work)
|
|
{
|
|
struct bpf_map *map = container_of(work, struct bpf_map, work);
|
|
|
|
/* implementation dependent freeing */
|
|
map->ops->map_free(map);
|
|
}
|
|
|
|
/* decrement map refcnt and schedule it for freeing via workqueue
|
|
* (unrelying map implementation ops->map_free() might sleep)
|
|
*/
|
|
void bpf_map_put(struct bpf_map *map)
|
|
{
|
|
if (atomic_dec_and_test(&map->refcnt)) {
|
|
INIT_WORK(&map->work, bpf_map_free_deferred);
|
|
schedule_work(&map->work);
|
|
}
|
|
}
|
|
|
|
static int bpf_map_release(struct inode *inode, struct file *filp)
|
|
{
|
|
struct bpf_map *map = filp->private_data;
|
|
|
|
bpf_map_put(map);
|
|
return 0;
|
|
}
|
|
|
|
static const struct file_operations bpf_map_fops = {
|
|
.release = bpf_map_release,
|
|
};
|
|
|
|
/* helper macro to check that unused fields 'union bpf_attr' are zero */
|
|
#define CHECK_ATTR(CMD) \
|
|
memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
|
|
sizeof(attr->CMD##_LAST_FIELD), 0, \
|
|
sizeof(*attr) - \
|
|
offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
|
|
sizeof(attr->CMD##_LAST_FIELD)) != NULL
|
|
|
|
#define BPF_MAP_CREATE_LAST_FIELD max_entries
|
|
/* called via syscall */
|
|
static int map_create(union bpf_attr *attr)
|
|
{
|
|
struct bpf_map *map;
|
|
int err;
|
|
|
|
err = CHECK_ATTR(BPF_MAP_CREATE);
|
|
if (err)
|
|
return -EINVAL;
|
|
|
|
/* find map type and init map: hashtable vs rbtree vs bloom vs ... */
|
|
map = find_and_alloc_map(attr);
|
|
if (IS_ERR(map))
|
|
return PTR_ERR(map);
|
|
|
|
atomic_set(&map->refcnt, 1);
|
|
|
|
err = anon_inode_getfd("bpf-map", &bpf_map_fops, map, O_RDWR | O_CLOEXEC);
|
|
|
|
if (err < 0)
|
|
/* failed to allocate fd */
|
|
goto free_map;
|
|
|
|
return err;
|
|
|
|
free_map:
|
|
map->ops->map_free(map);
|
|
return err;
|
|
}
|
|
|
|
/* if error is returned, fd is released.
|
|
* On success caller should complete fd access with matching fdput()
|
|
*/
|
|
struct bpf_map *bpf_map_get(struct fd f)
|
|
{
|
|
struct bpf_map *map;
|
|
|
|
if (!f.file)
|
|
return ERR_PTR(-EBADF);
|
|
|
|
if (f.file->f_op != &bpf_map_fops) {
|
|
fdput(f);
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
map = f.file->private_data;
|
|
|
|
return map;
|
|
}
|
|
|
|
/* helper to convert user pointers passed inside __aligned_u64 fields */
|
|
static void __user *u64_to_ptr(__u64 val)
|
|
{
|
|
return (void __user *) (unsigned long) val;
|
|
}
|
|
|
|
/* last field in 'union bpf_attr' used by this command */
|
|
#define BPF_MAP_LOOKUP_ELEM_LAST_FIELD value
|
|
|
|
static int map_lookup_elem(union bpf_attr *attr)
|
|
{
|
|
void __user *ukey = u64_to_ptr(attr->key);
|
|
void __user *uvalue = u64_to_ptr(attr->value);
|
|
int ufd = attr->map_fd;
|
|
struct fd f = fdget(ufd);
|
|
struct bpf_map *map;
|
|
void *key, *value, *ptr;
|
|
int err;
|
|
|
|
if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
|
|
return -EINVAL;
|
|
|
|
map = bpf_map_get(f);
|
|
if (IS_ERR(map))
|
|
return PTR_ERR(map);
|
|
|
|
err = -ENOMEM;
|
|
key = kmalloc(map->key_size, GFP_USER);
|
|
if (!key)
|
|
goto err_put;
|
|
|
|
err = -EFAULT;
|
|
if (copy_from_user(key, ukey, map->key_size) != 0)
|
|
goto free_key;
|
|
|
|
err = -ENOMEM;
|
|
value = kmalloc(map->value_size, GFP_USER);
|
|
if (!value)
|
|
goto free_key;
|
|
|
|
rcu_read_lock();
|
|
ptr = map->ops->map_lookup_elem(map, key);
|
|
if (ptr)
|
|
memcpy(value, ptr, map->value_size);
|
|
rcu_read_unlock();
|
|
|
|
err = -ENOENT;
|
|
if (!ptr)
|
|
goto free_value;
|
|
|
|
err = -EFAULT;
|
|
if (copy_to_user(uvalue, value, map->value_size) != 0)
|
|
goto free_value;
|
|
|
|
err = 0;
|
|
|
|
free_value:
|
|
kfree(value);
|
|
free_key:
|
|
kfree(key);
|
|
err_put:
|
|
fdput(f);
|
|
return err;
|
|
}
|
|
|
|
#define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
|
|
|
|
static int map_update_elem(union bpf_attr *attr)
|
|
{
|
|
void __user *ukey = u64_to_ptr(attr->key);
|
|
void __user *uvalue = u64_to_ptr(attr->value);
|
|
int ufd = attr->map_fd;
|
|
struct fd f = fdget(ufd);
|
|
struct bpf_map *map;
|
|
void *key, *value;
|
|
int err;
|
|
|
|
if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
|
|
return -EINVAL;
|
|
|
|
map = bpf_map_get(f);
|
|
if (IS_ERR(map))
|
|
return PTR_ERR(map);
|
|
|
|
err = -ENOMEM;
|
|
key = kmalloc(map->key_size, GFP_USER);
|
|
if (!key)
|
|
goto err_put;
|
|
|
|
err = -EFAULT;
|
|
if (copy_from_user(key, ukey, map->key_size) != 0)
|
|
goto free_key;
|
|
|
|
err = -ENOMEM;
|
|
value = kmalloc(map->value_size, GFP_USER);
|
|
if (!value)
|
|
goto free_key;
|
|
|
|
err = -EFAULT;
|
|
if (copy_from_user(value, uvalue, map->value_size) != 0)
|
|
goto free_value;
|
|
|
|
/* eBPF program that use maps are running under rcu_read_lock(),
|
|
* therefore all map accessors rely on this fact, so do the same here
|
|
*/
|
|
rcu_read_lock();
|
|
err = map->ops->map_update_elem(map, key, value, attr->flags);
|
|
rcu_read_unlock();
|
|
|
|
free_value:
|
|
kfree(value);
|
|
free_key:
|
|
kfree(key);
|
|
err_put:
|
|
fdput(f);
|
|
return err;
|
|
}
|
|
|
|
#define BPF_MAP_DELETE_ELEM_LAST_FIELD key
|
|
|
|
static int map_delete_elem(union bpf_attr *attr)
|
|
{
|
|
void __user *ukey = u64_to_ptr(attr->key);
|
|
int ufd = attr->map_fd;
|
|
struct fd f = fdget(ufd);
|
|
struct bpf_map *map;
|
|
void *key;
|
|
int err;
|
|
|
|
if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
|
|
return -EINVAL;
|
|
|
|
map = bpf_map_get(f);
|
|
if (IS_ERR(map))
|
|
return PTR_ERR(map);
|
|
|
|
err = -ENOMEM;
|
|
key = kmalloc(map->key_size, GFP_USER);
|
|
if (!key)
|
|
goto err_put;
|
|
|
|
err = -EFAULT;
|
|
if (copy_from_user(key, ukey, map->key_size) != 0)
|
|
goto free_key;
|
|
|
|
rcu_read_lock();
|
|
err = map->ops->map_delete_elem(map, key);
|
|
rcu_read_unlock();
|
|
|
|
free_key:
|
|
kfree(key);
|
|
err_put:
|
|
fdput(f);
|
|
return err;
|
|
}
|
|
|
|
/* last field in 'union bpf_attr' used by this command */
|
|
#define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
|
|
|
|
static int map_get_next_key(union bpf_attr *attr)
|
|
{
|
|
void __user *ukey = u64_to_ptr(attr->key);
|
|
void __user *unext_key = u64_to_ptr(attr->next_key);
|
|
int ufd = attr->map_fd;
|
|
struct fd f = fdget(ufd);
|
|
struct bpf_map *map;
|
|
void *key, *next_key;
|
|
int err;
|
|
|
|
if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
|
|
return -EINVAL;
|
|
|
|
map = bpf_map_get(f);
|
|
if (IS_ERR(map))
|
|
return PTR_ERR(map);
|
|
|
|
err = -ENOMEM;
|
|
key = kmalloc(map->key_size, GFP_USER);
|
|
if (!key)
|
|
goto err_put;
|
|
|
|
err = -EFAULT;
|
|
if (copy_from_user(key, ukey, map->key_size) != 0)
|
|
goto free_key;
|
|
|
|
err = -ENOMEM;
|
|
next_key = kmalloc(map->key_size, GFP_USER);
|
|
if (!next_key)
|
|
goto free_key;
|
|
|
|
rcu_read_lock();
|
|
err = map->ops->map_get_next_key(map, key, next_key);
|
|
rcu_read_unlock();
|
|
if (err)
|
|
goto free_next_key;
|
|
|
|
err = -EFAULT;
|
|
if (copy_to_user(unext_key, next_key, map->key_size) != 0)
|
|
goto free_next_key;
|
|
|
|
err = 0;
|
|
|
|
free_next_key:
|
|
kfree(next_key);
|
|
free_key:
|
|
kfree(key);
|
|
err_put:
|
|
fdput(f);
|
|
return err;
|
|
}
|
|
|
|
static LIST_HEAD(bpf_prog_types);
|
|
|
|
static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
|
|
{
|
|
struct bpf_prog_type_list *tl;
|
|
|
|
list_for_each_entry(tl, &bpf_prog_types, list_node) {
|
|
if (tl->type == type) {
|
|
prog->aux->ops = tl->ops;
|
|
prog->type = type;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
void bpf_register_prog_type(struct bpf_prog_type_list *tl)
|
|
{
|
|
list_add(&tl->list_node, &bpf_prog_types);
|
|
}
|
|
|
|
/* fixup insn->imm field of bpf_call instructions:
|
|
* if (insn->imm == BPF_FUNC_map_lookup_elem)
|
|
* insn->imm = bpf_map_lookup_elem - __bpf_call_base;
|
|
* else if (insn->imm == BPF_FUNC_map_update_elem)
|
|
* insn->imm = bpf_map_update_elem - __bpf_call_base;
|
|
* else ...
|
|
*
|
|
* this function is called after eBPF program passed verification
|
|
*/
|
|
static void fixup_bpf_calls(struct bpf_prog *prog)
|
|
{
|
|
const struct bpf_func_proto *fn;
|
|
int i;
|
|
|
|
for (i = 0; i < prog->len; i++) {
|
|
struct bpf_insn *insn = &prog->insnsi[i];
|
|
|
|
if (insn->code == (BPF_JMP | BPF_CALL)) {
|
|
/* we reach here when program has bpf_call instructions
|
|
* and it passed bpf_check(), means that
|
|
* ops->get_func_proto must have been supplied, check it
|
|
*/
|
|
BUG_ON(!prog->aux->ops->get_func_proto);
|
|
|
|
fn = prog->aux->ops->get_func_proto(insn->imm);
|
|
/* all functions that have prototype and verifier allowed
|
|
* programs to call them, must be real in-kernel functions
|
|
*/
|
|
BUG_ON(!fn->func);
|
|
insn->imm = fn->func - __bpf_call_base;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* drop refcnt on maps used by eBPF program and free auxilary data */
|
|
static void free_used_maps(struct bpf_prog_aux *aux)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < aux->used_map_cnt; i++)
|
|
bpf_map_put(aux->used_maps[i]);
|
|
|
|
kfree(aux->used_maps);
|
|
}
|
|
|
|
void bpf_prog_put(struct bpf_prog *prog)
|
|
{
|
|
if (atomic_dec_and_test(&prog->aux->refcnt)) {
|
|
free_used_maps(prog->aux);
|
|
bpf_prog_free(prog);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(bpf_prog_put);
|
|
|
|
static int bpf_prog_release(struct inode *inode, struct file *filp)
|
|
{
|
|
struct bpf_prog *prog = filp->private_data;
|
|
|
|
bpf_prog_put(prog);
|
|
return 0;
|
|
}
|
|
|
|
static const struct file_operations bpf_prog_fops = {
|
|
.release = bpf_prog_release,
|
|
};
|
|
|
|
static struct bpf_prog *get_prog(struct fd f)
|
|
{
|
|
struct bpf_prog *prog;
|
|
|
|
if (!f.file)
|
|
return ERR_PTR(-EBADF);
|
|
|
|
if (f.file->f_op != &bpf_prog_fops) {
|
|
fdput(f);
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
prog = f.file->private_data;
|
|
|
|
return prog;
|
|
}
|
|
|
|
/* called by sockets/tracing/seccomp before attaching program to an event
|
|
* pairs with bpf_prog_put()
|
|
*/
|
|
struct bpf_prog *bpf_prog_get(u32 ufd)
|
|
{
|
|
struct fd f = fdget(ufd);
|
|
struct bpf_prog *prog;
|
|
|
|
prog = get_prog(f);
|
|
|
|
if (IS_ERR(prog))
|
|
return prog;
|
|
|
|
atomic_inc(&prog->aux->refcnt);
|
|
fdput(f);
|
|
return prog;
|
|
}
|
|
EXPORT_SYMBOL_GPL(bpf_prog_get);
|
|
|
|
/* last field in 'union bpf_attr' used by this command */
|
|
#define BPF_PROG_LOAD_LAST_FIELD log_buf
|
|
|
|
static int bpf_prog_load(union bpf_attr *attr)
|
|
{
|
|
enum bpf_prog_type type = attr->prog_type;
|
|
struct bpf_prog *prog;
|
|
int err;
|
|
char license[128];
|
|
bool is_gpl;
|
|
|
|
if (CHECK_ATTR(BPF_PROG_LOAD))
|
|
return -EINVAL;
|
|
|
|
/* copy eBPF program license from user space */
|
|
if (strncpy_from_user(license, u64_to_ptr(attr->license),
|
|
sizeof(license) - 1) < 0)
|
|
return -EFAULT;
|
|
license[sizeof(license) - 1] = 0;
|
|
|
|
/* eBPF programs must be GPL compatible to use GPL-ed functions */
|
|
is_gpl = license_is_gpl_compatible(license);
|
|
|
|
if (attr->insn_cnt >= BPF_MAXINSNS)
|
|
return -EINVAL;
|
|
|
|
/* plain bpf_prog allocation */
|
|
prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
|
|
if (!prog)
|
|
return -ENOMEM;
|
|
|
|
prog->len = attr->insn_cnt;
|
|
|
|
err = -EFAULT;
|
|
if (copy_from_user(prog->insns, u64_to_ptr(attr->insns),
|
|
prog->len * sizeof(struct bpf_insn)) != 0)
|
|
goto free_prog;
|
|
|
|
prog->orig_prog = NULL;
|
|
prog->jited = false;
|
|
|
|
atomic_set(&prog->aux->refcnt, 1);
|
|
prog->gpl_compatible = is_gpl;
|
|
|
|
/* find program type: socket_filter vs tracing_filter */
|
|
err = find_prog_type(type, prog);
|
|
if (err < 0)
|
|
goto free_prog;
|
|
|
|
/* run eBPF verifier */
|
|
err = bpf_check(prog, attr);
|
|
if (err < 0)
|
|
goto free_used_maps;
|
|
|
|
/* fixup BPF_CALL->imm field */
|
|
fixup_bpf_calls(prog);
|
|
|
|
/* eBPF program is ready to be JITed */
|
|
bpf_prog_select_runtime(prog);
|
|
|
|
err = anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, O_RDWR | O_CLOEXEC);
|
|
if (err < 0)
|
|
/* failed to allocate fd */
|
|
goto free_used_maps;
|
|
|
|
return err;
|
|
|
|
free_used_maps:
|
|
free_used_maps(prog->aux);
|
|
free_prog:
|
|
bpf_prog_free(prog);
|
|
return err;
|
|
}
|
|
|
|
SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
|
|
{
|
|
union bpf_attr attr = {};
|
|
int err;
|
|
|
|
/* the syscall is limited to root temporarily. This restriction will be
|
|
* lifted when security audit is clean. Note that eBPF+tracing must have
|
|
* this restriction, since it may pass kernel data to user space
|
|
*/
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
|
|
if (!access_ok(VERIFY_READ, uattr, 1))
|
|
return -EFAULT;
|
|
|
|
if (size > PAGE_SIZE) /* silly large */
|
|
return -E2BIG;
|
|
|
|
/* If we're handed a bigger struct than we know of,
|
|
* ensure all the unknown bits are 0 - i.e. new
|
|
* user-space does not rely on any kernel feature
|
|
* extensions we dont know about yet.
|
|
*/
|
|
if (size > sizeof(attr)) {
|
|
unsigned char __user *addr;
|
|
unsigned char __user *end;
|
|
unsigned char val;
|
|
|
|
addr = (void __user *)uattr + sizeof(attr);
|
|
end = (void __user *)uattr + size;
|
|
|
|
for (; addr < end; addr++) {
|
|
err = get_user(val, addr);
|
|
if (err)
|
|
return err;
|
|
if (val)
|
|
return -E2BIG;
|
|
}
|
|
size = sizeof(attr);
|
|
}
|
|
|
|
/* copy attributes from user space, may be less than sizeof(bpf_attr) */
|
|
if (copy_from_user(&attr, uattr, size) != 0)
|
|
return -EFAULT;
|
|
|
|
switch (cmd) {
|
|
case BPF_MAP_CREATE:
|
|
err = map_create(&attr);
|
|
break;
|
|
case BPF_MAP_LOOKUP_ELEM:
|
|
err = map_lookup_elem(&attr);
|
|
break;
|
|
case BPF_MAP_UPDATE_ELEM:
|
|
err = map_update_elem(&attr);
|
|
break;
|
|
case BPF_MAP_DELETE_ELEM:
|
|
err = map_delete_elem(&attr);
|
|
break;
|
|
case BPF_MAP_GET_NEXT_KEY:
|
|
err = map_get_next_key(&attr);
|
|
break;
|
|
case BPF_PROG_LOAD:
|
|
err = bpf_prog_load(&attr);
|
|
break;
|
|
default:
|
|
err = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
return err;
|
|
}
|