| // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) |
| /* Copyright (c) 2019 Netronome Systems, Inc. */ |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <string.h> |
| #include <stdlib.h> |
| #include <unistd.h> |
| #include <net/if.h> |
| #include <sys/utsname.h> |
| |
| #include <linux/btf.h> |
| #include <linux/filter.h> |
| #include <linux/kernel.h> |
| |
| #include "bpf.h" |
| #include "libbpf.h" |
| #include "libbpf_internal.h" |
| |
| static bool grep(const char *buffer, const char *pattern) |
| { |
| return !!strstr(buffer, pattern); |
| } |
| |
| static int get_vendor_id(int ifindex) |
| { |
| char ifname[IF_NAMESIZE], path[64], buf[8]; |
| ssize_t len; |
| int fd; |
| |
| if (!if_indextoname(ifindex, ifname)) |
| return -1; |
| |
| snprintf(path, sizeof(path), "/sys/class/net/%s/device/vendor", ifname); |
| |
| fd = open(path, O_RDONLY); |
| if (fd < 0) |
| return -1; |
| |
| len = read(fd, buf, sizeof(buf)); |
| close(fd); |
| if (len < 0) |
| return -1; |
| if (len >= (ssize_t)sizeof(buf)) |
| return -1; |
| buf[len] = '\0'; |
| |
| return strtol(buf, NULL, 0); |
| } |
| |
| static int get_kernel_version(void) |
| { |
| int version, subversion, patchlevel; |
| struct utsname utsn; |
| |
| /* Return 0 on failure, and attempt to probe with empty kversion */ |
| if (uname(&utsn)) |
| return 0; |
| |
| if (sscanf(utsn.release, "%d.%d.%d", |
| &version, &subversion, &patchlevel) != 3) |
| return 0; |
| |
| return (version << 16) + (subversion << 8) + patchlevel; |
| } |
| |
| static void |
| probe_load(enum bpf_prog_type prog_type, const struct bpf_insn *insns, |
| size_t insns_cnt, char *buf, size_t buf_len, __u32 ifindex) |
| { |
| struct bpf_load_program_attr xattr = {}; |
| int fd; |
| |
| switch (prog_type) { |
| case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: |
| xattr.expected_attach_type = BPF_CGROUP_INET4_CONNECT; |
| break; |
| case BPF_PROG_TYPE_CGROUP_SOCKOPT: |
| xattr.expected_attach_type = BPF_CGROUP_GETSOCKOPT; |
| break; |
| case BPF_PROG_TYPE_SK_LOOKUP: |
| xattr.expected_attach_type = BPF_SK_LOOKUP; |
| break; |
| case BPF_PROG_TYPE_KPROBE: |
| xattr.kern_version = get_kernel_version(); |
| break; |
| case BPF_PROG_TYPE_UNSPEC: |
| case BPF_PROG_TYPE_SOCKET_FILTER: |
| case BPF_PROG_TYPE_SCHED_CLS: |
| case BPF_PROG_TYPE_SCHED_ACT: |
| case BPF_PROG_TYPE_TRACEPOINT: |
| case BPF_PROG_TYPE_XDP: |
| case BPF_PROG_TYPE_PERF_EVENT: |
| case BPF_PROG_TYPE_CGROUP_SKB: |
| case BPF_PROG_TYPE_CGROUP_SOCK: |
| case BPF_PROG_TYPE_LWT_IN: |
| case BPF_PROG_TYPE_LWT_OUT: |
| case BPF_PROG_TYPE_LWT_XMIT: |
| case BPF_PROG_TYPE_SOCK_OPS: |
| case BPF_PROG_TYPE_SK_SKB: |
| case BPF_PROG_TYPE_CGROUP_DEVICE: |
| case BPF_PROG_TYPE_SK_MSG: |
| case BPF_PROG_TYPE_RAW_TRACEPOINT: |
| case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: |
| case BPF_PROG_TYPE_LWT_SEG6LOCAL: |
| case BPF_PROG_TYPE_LIRC_MODE2: |
| case BPF_PROG_TYPE_SK_REUSEPORT: |
| case BPF_PROG_TYPE_FLOW_DISSECTOR: |
| case BPF_PROG_TYPE_CGROUP_SYSCTL: |
| case BPF_PROG_TYPE_TRACING: |
| case BPF_PROG_TYPE_STRUCT_OPS: |
| case BPF_PROG_TYPE_EXT: |
| case BPF_PROG_TYPE_LSM: |
| default: |
| break; |
| } |
| |
| xattr.prog_type = prog_type; |
| xattr.insns = insns; |
| xattr.insns_cnt = insns_cnt; |
| xattr.license = "GPL"; |
| xattr.prog_ifindex = ifindex; |
| |
| fd = bpf_load_program_xattr(&xattr, buf, buf_len); |
| if (fd >= 0) |
| close(fd); |
| } |
| |
| bool bpf_probe_prog_type(enum bpf_prog_type prog_type, __u32 ifindex) |
| { |
| struct bpf_insn insns[2] = { |
| BPF_MOV64_IMM(BPF_REG_0, 0), |
| BPF_EXIT_INSN() |
| }; |
| |
| if (ifindex && prog_type == BPF_PROG_TYPE_SCHED_CLS) |
| /* nfp returns -EINVAL on exit(0) with TC offload */ |
| insns[0].imm = 2; |
| |
| errno = 0; |
| probe_load(prog_type, insns, ARRAY_SIZE(insns), NULL, 0, ifindex); |
| |
| return errno != EINVAL && errno != EOPNOTSUPP; |
| } |
| |
| int libbpf__load_raw_btf(const char *raw_types, size_t types_len, |
| const char *str_sec, size_t str_len) |
| { |
| struct btf_header hdr = { |
| .magic = BTF_MAGIC, |
| .version = BTF_VERSION, |
| .hdr_len = sizeof(struct btf_header), |
| .type_len = types_len, |
| .str_off = types_len, |
| .str_len = str_len, |
| }; |
| int btf_fd, btf_len; |
| __u8 *raw_btf; |
| |
| btf_len = hdr.hdr_len + hdr.type_len + hdr.str_len; |
| raw_btf = malloc(btf_len); |
| if (!raw_btf) |
| return -ENOMEM; |
| |
| memcpy(raw_btf, &hdr, sizeof(hdr)); |
| memcpy(raw_btf + hdr.hdr_len, raw_types, hdr.type_len); |
| memcpy(raw_btf + hdr.hdr_len + hdr.type_len, str_sec, hdr.str_len); |
| |
| btf_fd = bpf_load_btf(raw_btf, btf_len, NULL, 0, false); |
| |
| free(raw_btf); |
| return btf_fd; |
| } |
| |
| static int load_local_storage_btf(void) |
| { |
| const char strs[] = "\0bpf_spin_lock\0val\0cnt\0l"; |
| /* struct bpf_spin_lock { |
| * int val; |
| * }; |
| * struct val { |
| * int cnt; |
| * struct bpf_spin_lock l; |
| * }; |
| */ |
| __u32 types[] = { |
| /* int */ |
| BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ |
| /* struct bpf_spin_lock */ /* [2] */ |
| BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 1), 4), |
| BTF_MEMBER_ENC(15, 1, 0), /* int val; */ |
| /* struct val */ /* [3] */ |
| BTF_TYPE_ENC(15, BTF_INFO_ENC(BTF_KIND_STRUCT, 0, 2), 8), |
| BTF_MEMBER_ENC(19, 1, 0), /* int cnt; */ |
| BTF_MEMBER_ENC(23, 2, 32),/* struct bpf_spin_lock l; */ |
| }; |
| |
| return libbpf__load_raw_btf((char *)types, sizeof(types), |
| strs, sizeof(strs)); |
| } |
| |
| bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex) |
| { |
| int key_size, value_size, max_entries, map_flags; |
| __u32 btf_key_type_id = 0, btf_value_type_id = 0; |
| struct bpf_create_map_attr attr = {}; |
| int fd = -1, btf_fd = -1, fd_inner; |
| |
| key_size = sizeof(__u32); |
| value_size = sizeof(__u32); |
| max_entries = 1; |
| map_flags = 0; |
| |
| switch (map_type) { |
| case BPF_MAP_TYPE_STACK_TRACE: |
| value_size = sizeof(__u64); |
| break; |
| case BPF_MAP_TYPE_LPM_TRIE: |
| key_size = sizeof(__u64); |
| value_size = sizeof(__u64); |
| map_flags = BPF_F_NO_PREALLOC; |
| break; |
| case BPF_MAP_TYPE_CGROUP_STORAGE: |
| case BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE: |
| key_size = sizeof(struct bpf_cgroup_storage_key); |
| value_size = sizeof(__u64); |
| max_entries = 0; |
| break; |
| case BPF_MAP_TYPE_QUEUE: |
| case BPF_MAP_TYPE_STACK: |
| key_size = 0; |
| break; |
| case BPF_MAP_TYPE_SK_STORAGE: |
| case BPF_MAP_TYPE_INODE_STORAGE: |
| case BPF_MAP_TYPE_TASK_STORAGE: |
| btf_key_type_id = 1; |
| btf_value_type_id = 3; |
| value_size = 8; |
| max_entries = 0; |
| map_flags = BPF_F_NO_PREALLOC; |
| btf_fd = load_local_storage_btf(); |
| if (btf_fd < 0) |
| return false; |
| break; |
| case BPF_MAP_TYPE_RINGBUF: |
| key_size = 0; |
| value_size = 0; |
| max_entries = 4096; |
| break; |
| case BPF_MAP_TYPE_UNSPEC: |
| case BPF_MAP_TYPE_HASH: |
| case BPF_MAP_TYPE_ARRAY: |
| case BPF_MAP_TYPE_PROG_ARRAY: |
| case BPF_MAP_TYPE_PERF_EVENT_ARRAY: |
| case BPF_MAP_TYPE_PERCPU_HASH: |
| case BPF_MAP_TYPE_PERCPU_ARRAY: |
| case BPF_MAP_TYPE_CGROUP_ARRAY: |
| case BPF_MAP_TYPE_LRU_HASH: |
| case BPF_MAP_TYPE_LRU_PERCPU_HASH: |
| case BPF_MAP_TYPE_ARRAY_OF_MAPS: |
| case BPF_MAP_TYPE_HASH_OF_MAPS: |
| case BPF_MAP_TYPE_DEVMAP: |
| case BPF_MAP_TYPE_DEVMAP_HASH: |
| case BPF_MAP_TYPE_SOCKMAP: |
| case BPF_MAP_TYPE_CPUMAP: |
| case BPF_MAP_TYPE_XSKMAP: |
| case BPF_MAP_TYPE_SOCKHASH: |
| case BPF_MAP_TYPE_REUSEPORT_SOCKARRAY: |
| case BPF_MAP_TYPE_STRUCT_OPS: |
| default: |
| break; |
| } |
| |
| if (map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS || |
| map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { |
| /* TODO: probe for device, once libbpf has a function to create |
| * map-in-map for offload |
| */ |
| if (ifindex) |
| return false; |
| |
| fd_inner = bpf_create_map(BPF_MAP_TYPE_HASH, |
| sizeof(__u32), sizeof(__u32), 1, 0); |
| if (fd_inner < 0) |
| return false; |
| fd = bpf_create_map_in_map(map_type, NULL, sizeof(__u32), |
| fd_inner, 1, 0); |
| close(fd_inner); |
| } else { |
| /* Note: No other restriction on map type probes for offload */ |
| attr.map_type = map_type; |
| attr.key_size = key_size; |
| attr.value_size = value_size; |
| attr.max_entries = max_entries; |
| attr.map_flags = map_flags; |
| attr.map_ifindex = ifindex; |
| if (btf_fd >= 0) { |
| attr.btf_fd = btf_fd; |
| attr.btf_key_type_id = btf_key_type_id; |
| attr.btf_value_type_id = btf_value_type_id; |
| } |
| |
| fd = bpf_create_map_xattr(&attr); |
| } |
| if (fd >= 0) |
| close(fd); |
| if (btf_fd >= 0) |
| close(btf_fd); |
| |
| return fd >= 0; |
| } |
| |
| bool bpf_probe_helper(enum bpf_func_id id, enum bpf_prog_type prog_type, |
| __u32 ifindex) |
| { |
| struct bpf_insn insns[2] = { |
| BPF_EMIT_CALL(id), |
| BPF_EXIT_INSN() |
| }; |
| char buf[4096] = {}; |
| bool res; |
| |
| probe_load(prog_type, insns, ARRAY_SIZE(insns), buf, sizeof(buf), |
| ifindex); |
| res = !grep(buf, "invalid func ") && !grep(buf, "unknown func "); |
| |
| if (ifindex) { |
| switch (get_vendor_id(ifindex)) { |
| case 0x19ee: /* Netronome specific */ |
| res = res && !grep(buf, "not supported by FW") && |
| !grep(buf, "unsupported function id"); |
| break; |
| default: |
| break; |
| } |
| } |
| |
| return res; |
| } |
| |
| /* |
| * Probe for availability of kernel commit (5.3): |
| * |
| * c04c0d2b968a ("bpf: increase complexity limit and maximum program size") |
| */ |
| bool bpf_probe_large_insn_limit(__u32 ifindex) |
| { |
| struct bpf_insn insns[BPF_MAXINSNS + 1]; |
| int i; |
| |
| for (i = 0; i < BPF_MAXINSNS; i++) |
| insns[i] = BPF_MOV64_IMM(BPF_REG_0, 1); |
| insns[BPF_MAXINSNS] = BPF_EXIT_INSN(); |
| |
| errno = 0; |
| probe_load(BPF_PROG_TYPE_SCHED_CLS, insns, ARRAY_SIZE(insns), NULL, 0, |
| ifindex); |
| |
| return errno != E2BIG && errno != EINVAL; |
| } |