| /* |
| * Copyright (C) 2017 Netronome Systems, Inc. |
| * |
| * This software is licensed under the GNU General License Version 2, |
| * June 1991 as shown in the file COPYING in the top-level directory of this |
| * source tree. |
| * |
| * THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" |
| * WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, |
| * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| * FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE |
| * OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME |
| * THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. |
| */ |
| |
| #include <linux/bpf.h> |
| #include <linux/bpf_verifier.h> |
| #include <linux/debugfs.h> |
| #include <linux/kernel.h> |
| #include <linux/mutex.h> |
| #include <linux/rtnetlink.h> |
| #include <net/pkt_cls.h> |
| |
| #include "netdevsim.h" |
| |
| #define pr_vlog(env, fmt, ...) \ |
| bpf_verifier_log_write(env, "[netdevsim] " fmt, ##__VA_ARGS__) |
| |
| struct nsim_bpf_bound_prog { |
| struct netdevsim *ns; |
| struct bpf_prog *prog; |
| struct dentry *ddir; |
| const char *state; |
| bool is_loaded; |
| struct list_head l; |
| }; |
| |
| #define NSIM_BPF_MAX_KEYS 2 |
| |
| struct nsim_bpf_bound_map { |
| struct netdevsim *ns; |
| struct bpf_offloaded_map *map; |
| struct mutex mutex; |
| struct nsim_map_entry { |
| void *key; |
| void *value; |
| } entry[NSIM_BPF_MAX_KEYS]; |
| struct list_head l; |
| }; |
| |
| static int nsim_debugfs_bpf_string_read(struct seq_file *file, void *data) |
| { |
| const char **str = file->private; |
| |
| if (*str) |
| seq_printf(file, "%s\n", *str); |
| |
| return 0; |
| } |
| |
| static int nsim_debugfs_bpf_string_open(struct inode *inode, struct file *f) |
| { |
| return single_open(f, nsim_debugfs_bpf_string_read, inode->i_private); |
| } |
| |
| static const struct file_operations nsim_bpf_string_fops = { |
| .owner = THIS_MODULE, |
| .open = nsim_debugfs_bpf_string_open, |
| .release = single_release, |
| .read = seq_read, |
| .llseek = seq_lseek |
| }; |
| |
| static int |
| nsim_bpf_verify_insn(struct bpf_verifier_env *env, int insn_idx, int prev_insn) |
| { |
| struct nsim_bpf_bound_prog *state; |
| |
| state = env->prog->aux->offload->dev_priv; |
| if (state->ns->bpf_bind_verifier_delay && !insn_idx) |
| msleep(state->ns->bpf_bind_verifier_delay); |
| |
| if (insn_idx == env->prog->len - 1) |
| pr_vlog(env, "Hello from netdevsim!\n"); |
| |
| return 0; |
| } |
| |
| static const struct bpf_prog_offload_ops nsim_bpf_analyzer_ops = { |
| .insn_hook = nsim_bpf_verify_insn, |
| }; |
| |
| static bool nsim_xdp_offload_active(struct netdevsim *ns) |
| { |
| return ns->xdp_hw.prog; |
| } |
| |
| static void nsim_prog_set_loaded(struct bpf_prog *prog, bool loaded) |
| { |
| struct nsim_bpf_bound_prog *state; |
| |
| if (!prog || !prog->aux->offload) |
| return; |
| |
| state = prog->aux->offload->dev_priv; |
| state->is_loaded = loaded; |
| } |
| |
| static int |
| nsim_bpf_offload(struct netdevsim *ns, struct bpf_prog *prog, bool oldprog) |
| { |
| nsim_prog_set_loaded(ns->bpf_offloaded, false); |
| |
| WARN(!!ns->bpf_offloaded != oldprog, |
| "bad offload state, expected offload %sto be active", |
| oldprog ? "" : "not "); |
| ns->bpf_offloaded = prog; |
| ns->bpf_offloaded_id = prog ? prog->aux->id : 0; |
| nsim_prog_set_loaded(prog, true); |
| |
| return 0; |
| } |
| |
| int nsim_bpf_setup_tc_block_cb(enum tc_setup_type type, |
| void *type_data, void *cb_priv) |
| { |
| struct tc_cls_bpf_offload *cls_bpf = type_data; |
| struct bpf_prog *prog = cls_bpf->prog; |
| struct netdevsim *ns = cb_priv; |
| struct bpf_prog *oldprog; |
| |
| if (type != TC_SETUP_CLSBPF) { |
| NSIM_EA(cls_bpf->common.extack, |
| "only offload of BPF classifiers supported"); |
| return -EOPNOTSUPP; |
| } |
| |
| if (!tc_cls_can_offload_and_chain0(ns->netdev, &cls_bpf->common)) |
| return -EOPNOTSUPP; |
| |
| if (cls_bpf->common.protocol != htons(ETH_P_ALL)) { |
| NSIM_EA(cls_bpf->common.extack, |
| "only ETH_P_ALL supported as filter protocol"); |
| return -EOPNOTSUPP; |
| } |
| |
| if (!ns->bpf_tc_accept) { |
| NSIM_EA(cls_bpf->common.extack, |
| "netdevsim configured to reject BPF TC offload"); |
| return -EOPNOTSUPP; |
| } |
| /* Note: progs without skip_sw will probably not be dev bound */ |
| if (prog && !prog->aux->offload && !ns->bpf_tc_non_bound_accept) { |
| NSIM_EA(cls_bpf->common.extack, |
| "netdevsim configured to reject unbound programs"); |
| return -EOPNOTSUPP; |
| } |
| |
| if (cls_bpf->command != TC_CLSBPF_OFFLOAD) |
| return -EOPNOTSUPP; |
| |
| oldprog = cls_bpf->oldprog; |
| |
| /* Don't remove if oldprog doesn't match driver's state */ |
| if (ns->bpf_offloaded != oldprog) { |
| oldprog = NULL; |
| if (!cls_bpf->prog) |
| return 0; |
| if (ns->bpf_offloaded) { |
| NSIM_EA(cls_bpf->common.extack, |
| "driver and netdev offload states mismatch"); |
| return -EBUSY; |
| } |
| } |
| |
| return nsim_bpf_offload(ns, cls_bpf->prog, oldprog); |
| } |
| |
| int nsim_bpf_disable_tc(struct netdevsim *ns) |
| { |
| if (ns->bpf_offloaded && !nsim_xdp_offload_active(ns)) |
| return -EBUSY; |
| return 0; |
| } |
| |
| static int nsim_xdp_offload_prog(struct netdevsim *ns, struct netdev_bpf *bpf) |
| { |
| if (!nsim_xdp_offload_active(ns) && !bpf->prog) |
| return 0; |
| if (!nsim_xdp_offload_active(ns) && bpf->prog && ns->bpf_offloaded) { |
| NSIM_EA(bpf->extack, "TC program is already loaded"); |
| return -EBUSY; |
| } |
| |
| return nsim_bpf_offload(ns, bpf->prog, nsim_xdp_offload_active(ns)); |
| } |
| |
| static int |
| nsim_xdp_set_prog(struct netdevsim *ns, struct netdev_bpf *bpf, |
| struct xdp_attachment_info *xdp) |
| { |
| int err; |
| |
| if (!xdp_attachment_flags_ok(xdp, bpf)) |
| return -EBUSY; |
| |
| if (bpf->command == XDP_SETUP_PROG && !ns->bpf_xdpdrv_accept) { |
| NSIM_EA(bpf->extack, "driver XDP disabled in DebugFS"); |
| return -EOPNOTSUPP; |
| } |
| if (bpf->command == XDP_SETUP_PROG_HW && !ns->bpf_xdpoffload_accept) { |
| NSIM_EA(bpf->extack, "XDP offload disabled in DebugFS"); |
| return -EOPNOTSUPP; |
| } |
| |
| if (bpf->command == XDP_SETUP_PROG_HW) { |
| err = nsim_xdp_offload_prog(ns, bpf); |
| if (err) |
| return err; |
| } |
| |
| xdp_attachment_setup(xdp, bpf); |
| |
| return 0; |
| } |
| |
| static int nsim_bpf_create_prog(struct netdevsim *ns, struct bpf_prog *prog) |
| { |
| struct nsim_bpf_bound_prog *state; |
| char name[16]; |
| |
| state = kzalloc(sizeof(*state), GFP_KERNEL); |
| if (!state) |
| return -ENOMEM; |
| |
| state->ns = ns; |
| state->prog = prog; |
| state->state = "verify"; |
| |
| /* Program id is not populated yet when we create the state. */ |
| sprintf(name, "%u", ns->sdev->prog_id_gen++); |
| state->ddir = debugfs_create_dir(name, ns->sdev->ddir_bpf_bound_progs); |
| if (IS_ERR_OR_NULL(state->ddir)) { |
| kfree(state); |
| return -ENOMEM; |
| } |
| |
| debugfs_create_u32("id", 0400, state->ddir, &prog->aux->id); |
| debugfs_create_file("state", 0400, state->ddir, |
| &state->state, &nsim_bpf_string_fops); |
| debugfs_create_bool("loaded", 0400, state->ddir, &state->is_loaded); |
| |
| list_add_tail(&state->l, &ns->sdev->bpf_bound_progs); |
| |
| prog->aux->offload->dev_priv = state; |
| |
| return 0; |
| } |
| |
| static void nsim_bpf_destroy_prog(struct bpf_prog *prog) |
| { |
| struct nsim_bpf_bound_prog *state; |
| |
| state = prog->aux->offload->dev_priv; |
| WARN(state->is_loaded, |
| "offload state destroyed while program still bound"); |
| debugfs_remove_recursive(state->ddir); |
| list_del(&state->l); |
| kfree(state); |
| } |
| |
| static int nsim_setup_prog_checks(struct netdevsim *ns, struct netdev_bpf *bpf) |
| { |
| if (bpf->prog && bpf->prog->aux->offload) { |
| NSIM_EA(bpf->extack, "attempt to load offloaded prog to drv"); |
| return -EINVAL; |
| } |
| if (ns->netdev->mtu > NSIM_XDP_MAX_MTU) { |
| NSIM_EA(bpf->extack, "MTU too large w/ XDP enabled"); |
| return -EINVAL; |
| } |
| return 0; |
| } |
| |
| static int |
| nsim_setup_prog_hw_checks(struct netdevsim *ns, struct netdev_bpf *bpf) |
| { |
| struct nsim_bpf_bound_prog *state; |
| |
| if (!bpf->prog) |
| return 0; |
| |
| if (!bpf->prog->aux->offload) { |
| NSIM_EA(bpf->extack, "xdpoffload of non-bound program"); |
| return -EINVAL; |
| } |
| if (!bpf_offload_dev_match(bpf->prog, ns->netdev)) { |
| NSIM_EA(bpf->extack, "program bound to different dev"); |
| return -EINVAL; |
| } |
| |
| state = bpf->prog->aux->offload->dev_priv; |
| if (WARN_ON(strcmp(state->state, "xlated"))) { |
| NSIM_EA(bpf->extack, "offloading program in bad state"); |
| return -EINVAL; |
| } |
| return 0; |
| } |
| |
| static bool |
| nsim_map_key_match(struct bpf_map *map, struct nsim_map_entry *e, void *key) |
| { |
| return e->key && !memcmp(key, e->key, map->key_size); |
| } |
| |
| static int nsim_map_key_find(struct bpf_offloaded_map *offmap, void *key) |
| { |
| struct nsim_bpf_bound_map *nmap = offmap->dev_priv; |
| unsigned int i; |
| |
| for (i = 0; i < ARRAY_SIZE(nmap->entry); i++) |
| if (nsim_map_key_match(&offmap->map, &nmap->entry[i], key)) |
| return i; |
| |
| return -ENOENT; |
| } |
| |
| static int |
| nsim_map_alloc_elem(struct bpf_offloaded_map *offmap, unsigned int idx) |
| { |
| struct nsim_bpf_bound_map *nmap = offmap->dev_priv; |
| |
| nmap->entry[idx].key = kmalloc(offmap->map.key_size, GFP_USER); |
| if (!nmap->entry[idx].key) |
| return -ENOMEM; |
| nmap->entry[idx].value = kmalloc(offmap->map.value_size, GFP_USER); |
| if (!nmap->entry[idx].value) { |
| kfree(nmap->entry[idx].key); |
| nmap->entry[idx].key = NULL; |
| return -ENOMEM; |
| } |
| |
| return 0; |
| } |
| |
| static int |
| nsim_map_get_next_key(struct bpf_offloaded_map *offmap, |
| void *key, void *next_key) |
| { |
| struct nsim_bpf_bound_map *nmap = offmap->dev_priv; |
| int idx = -ENOENT; |
| |
| mutex_lock(&nmap->mutex); |
| |
| if (key) |
| idx = nsim_map_key_find(offmap, key); |
| if (idx == -ENOENT) |
| idx = 0; |
| else |
| idx++; |
| |
| for (; idx < ARRAY_SIZE(nmap->entry); idx++) { |
| if (nmap->entry[idx].key) { |
| memcpy(next_key, nmap->entry[idx].key, |
| offmap->map.key_size); |
| break; |
| } |
| } |
| |
| mutex_unlock(&nmap->mutex); |
| |
| if (idx == ARRAY_SIZE(nmap->entry)) |
| return -ENOENT; |
| return 0; |
| } |
| |
| static int |
| nsim_map_lookup_elem(struct bpf_offloaded_map *offmap, void *key, void *value) |
| { |
| struct nsim_bpf_bound_map *nmap = offmap->dev_priv; |
| int idx; |
| |
| mutex_lock(&nmap->mutex); |
| |
| idx = nsim_map_key_find(offmap, key); |
| if (idx >= 0) |
| memcpy(value, nmap->entry[idx].value, offmap->map.value_size); |
| |
| mutex_unlock(&nmap->mutex); |
| |
| return idx < 0 ? idx : 0; |
| } |
| |
| static int |
| nsim_map_update_elem(struct bpf_offloaded_map *offmap, |
| void *key, void *value, u64 flags) |
| { |
| struct nsim_bpf_bound_map *nmap = offmap->dev_priv; |
| int idx, err = 0; |
| |
| mutex_lock(&nmap->mutex); |
| |
| idx = nsim_map_key_find(offmap, key); |
| if (idx < 0 && flags == BPF_EXIST) { |
| err = idx; |
| goto exit_unlock; |
| } |
| if (idx >= 0 && flags == BPF_NOEXIST) { |
| err = -EEXIST; |
| goto exit_unlock; |
| } |
| |
| if (idx < 0) { |
| for (idx = 0; idx < ARRAY_SIZE(nmap->entry); idx++) |
| if (!nmap->entry[idx].key) |
| break; |
| if (idx == ARRAY_SIZE(nmap->entry)) { |
| err = -E2BIG; |
| goto exit_unlock; |
| } |
| |
| err = nsim_map_alloc_elem(offmap, idx); |
| if (err) |
| goto exit_unlock; |
| } |
| |
| memcpy(nmap->entry[idx].key, key, offmap->map.key_size); |
| memcpy(nmap->entry[idx].value, value, offmap->map.value_size); |
| exit_unlock: |
| mutex_unlock(&nmap->mutex); |
| |
| return err; |
| } |
| |
| static int nsim_map_delete_elem(struct bpf_offloaded_map *offmap, void *key) |
| { |
| struct nsim_bpf_bound_map *nmap = offmap->dev_priv; |
| int idx; |
| |
| if (offmap->map.map_type == BPF_MAP_TYPE_ARRAY) |
| return -EINVAL; |
| |
| mutex_lock(&nmap->mutex); |
| |
| idx = nsim_map_key_find(offmap, key); |
| if (idx >= 0) { |
| kfree(nmap->entry[idx].key); |
| kfree(nmap->entry[idx].value); |
| memset(&nmap->entry[idx], 0, sizeof(nmap->entry[idx])); |
| } |
| |
| mutex_unlock(&nmap->mutex); |
| |
| return idx < 0 ? idx : 0; |
| } |
| |
| static const struct bpf_map_dev_ops nsim_bpf_map_ops = { |
| .map_get_next_key = nsim_map_get_next_key, |
| .map_lookup_elem = nsim_map_lookup_elem, |
| .map_update_elem = nsim_map_update_elem, |
| .map_delete_elem = nsim_map_delete_elem, |
| }; |
| |
| static int |
| nsim_bpf_map_alloc(struct netdevsim *ns, struct bpf_offloaded_map *offmap) |
| { |
| struct nsim_bpf_bound_map *nmap; |
| int i, err; |
| |
| if (WARN_ON(offmap->map.map_type != BPF_MAP_TYPE_ARRAY && |
| offmap->map.map_type != BPF_MAP_TYPE_HASH)) |
| return -EINVAL; |
| if (offmap->map.max_entries > NSIM_BPF_MAX_KEYS) |
| return -ENOMEM; |
| if (offmap->map.map_flags) |
| return -EINVAL; |
| |
| nmap = kzalloc(sizeof(*nmap), GFP_USER); |
| if (!nmap) |
| return -ENOMEM; |
| |
| offmap->dev_priv = nmap; |
| nmap->ns = ns; |
| nmap->map = offmap; |
| mutex_init(&nmap->mutex); |
| |
| if (offmap->map.map_type == BPF_MAP_TYPE_ARRAY) { |
| for (i = 0; i < ARRAY_SIZE(nmap->entry); i++) { |
| u32 *key; |
| |
| err = nsim_map_alloc_elem(offmap, i); |
| if (err) |
| goto err_free; |
| key = nmap->entry[i].key; |
| *key = i; |
| memset(nmap->entry[i].value, 0, offmap->map.value_size); |
| } |
| } |
| |
| offmap->dev_ops = &nsim_bpf_map_ops; |
| list_add_tail(&nmap->l, &ns->sdev->bpf_bound_maps); |
| |
| return 0; |
| |
| err_free: |
| while (--i >= 0) { |
| kfree(nmap->entry[i].key); |
| kfree(nmap->entry[i].value); |
| } |
| kfree(nmap); |
| return err; |
| } |
| |
| static void nsim_bpf_map_free(struct bpf_offloaded_map *offmap) |
| { |
| struct nsim_bpf_bound_map *nmap = offmap->dev_priv; |
| unsigned int i; |
| |
| for (i = 0; i < ARRAY_SIZE(nmap->entry); i++) { |
| kfree(nmap->entry[i].key); |
| kfree(nmap->entry[i].value); |
| } |
| list_del_init(&nmap->l); |
| mutex_destroy(&nmap->mutex); |
| kfree(nmap); |
| } |
| |
| int nsim_bpf(struct net_device *dev, struct netdev_bpf *bpf) |
| { |
| struct netdevsim *ns = netdev_priv(dev); |
| struct nsim_bpf_bound_prog *state; |
| int err; |
| |
| ASSERT_RTNL(); |
| |
| switch (bpf->command) { |
| case BPF_OFFLOAD_VERIFIER_PREP: |
| if (!ns->bpf_bind_accept) |
| return -EOPNOTSUPP; |
| |
| err = nsim_bpf_create_prog(ns, bpf->verifier.prog); |
| if (err) |
| return err; |
| |
| bpf->verifier.ops = &nsim_bpf_analyzer_ops; |
| return 0; |
| case BPF_OFFLOAD_TRANSLATE: |
| state = bpf->offload.prog->aux->offload->dev_priv; |
| |
| state->state = "xlated"; |
| return 0; |
| case BPF_OFFLOAD_DESTROY: |
| nsim_bpf_destroy_prog(bpf->offload.prog); |
| return 0; |
| case XDP_QUERY_PROG: |
| return xdp_attachment_query(&ns->xdp, bpf); |
| case XDP_QUERY_PROG_HW: |
| return xdp_attachment_query(&ns->xdp_hw, bpf); |
| case XDP_SETUP_PROG: |
| err = nsim_setup_prog_checks(ns, bpf); |
| if (err) |
| return err; |
| |
| return nsim_xdp_set_prog(ns, bpf, &ns->xdp); |
| case XDP_SETUP_PROG_HW: |
| err = nsim_setup_prog_hw_checks(ns, bpf); |
| if (err) |
| return err; |
| |
| return nsim_xdp_set_prog(ns, bpf, &ns->xdp_hw); |
| case BPF_OFFLOAD_MAP_ALLOC: |
| if (!ns->bpf_map_accept) |
| return -EOPNOTSUPP; |
| |
| return nsim_bpf_map_alloc(ns, bpf->offmap); |
| case BPF_OFFLOAD_MAP_FREE: |
| nsim_bpf_map_free(bpf->offmap); |
| return 0; |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| int nsim_bpf_init(struct netdevsim *ns) |
| { |
| int err; |
| |
| if (ns->sdev->refcnt == 1) { |
| INIT_LIST_HEAD(&ns->sdev->bpf_bound_progs); |
| INIT_LIST_HEAD(&ns->sdev->bpf_bound_maps); |
| |
| ns->sdev->ddir_bpf_bound_progs = |
| debugfs_create_dir("bpf_bound_progs", ns->sdev->ddir); |
| if (IS_ERR_OR_NULL(ns->sdev->ddir_bpf_bound_progs)) |
| return -ENOMEM; |
| |
| ns->sdev->bpf_dev = bpf_offload_dev_create(); |
| err = PTR_ERR_OR_ZERO(ns->sdev->bpf_dev); |
| if (err) |
| return err; |
| } |
| |
| err = bpf_offload_dev_netdev_register(ns->sdev->bpf_dev, ns->netdev); |
| if (err) |
| goto err_destroy_bdev; |
| |
| debugfs_create_u32("bpf_offloaded_id", 0400, ns->ddir, |
| &ns->bpf_offloaded_id); |
| |
| ns->bpf_bind_accept = true; |
| debugfs_create_bool("bpf_bind_accept", 0600, ns->ddir, |
| &ns->bpf_bind_accept); |
| debugfs_create_u32("bpf_bind_verifier_delay", 0600, ns->ddir, |
| &ns->bpf_bind_verifier_delay); |
| |
| ns->bpf_tc_accept = true; |
| debugfs_create_bool("bpf_tc_accept", 0600, ns->ddir, |
| &ns->bpf_tc_accept); |
| debugfs_create_bool("bpf_tc_non_bound_accept", 0600, ns->ddir, |
| &ns->bpf_tc_non_bound_accept); |
| ns->bpf_xdpdrv_accept = true; |
| debugfs_create_bool("bpf_xdpdrv_accept", 0600, ns->ddir, |
| &ns->bpf_xdpdrv_accept); |
| ns->bpf_xdpoffload_accept = true; |
| debugfs_create_bool("bpf_xdpoffload_accept", 0600, ns->ddir, |
| &ns->bpf_xdpoffload_accept); |
| |
| ns->bpf_map_accept = true; |
| debugfs_create_bool("bpf_map_accept", 0600, ns->ddir, |
| &ns->bpf_map_accept); |
| |
| return 0; |
| |
| err_destroy_bdev: |
| if (ns->sdev->refcnt == 1) |
| bpf_offload_dev_destroy(ns->sdev->bpf_dev); |
| return err; |
| } |
| |
| void nsim_bpf_uninit(struct netdevsim *ns) |
| { |
| WARN_ON(ns->xdp.prog); |
| WARN_ON(ns->xdp_hw.prog); |
| WARN_ON(ns->bpf_offloaded); |
| bpf_offload_dev_netdev_unregister(ns->sdev->bpf_dev, ns->netdev); |
| |
| if (ns->sdev->refcnt == 1) { |
| WARN_ON(!list_empty(&ns->sdev->bpf_bound_progs)); |
| WARN_ON(!list_empty(&ns->sdev->bpf_bound_maps)); |
| bpf_offload_dev_destroy(ns->sdev->bpf_dev); |
| } |
| } |