From 1dc0296fce424e85b4fac0274d9b41d34b63581e Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Mon, 4 Feb 2019 13:28:44 -0800 Subject: [PATCH] sync with latest bpf-next The following three files are added: libbpf_probes.c libbpf_util.h libbpf.map Signed-off-by: Yonghong Song --- src/README.rst | 14 +++ src/bpf.c | 32 +++++- src/bpf.h | 2 + src/btf.c | 183 ++++++++++++++++++++++----------- src/btf.h | 33 +++--- src/libbpf.c | 173 +++++++++++++++---------------- src/libbpf.h | 38 +++++-- src/libbpf.map | 143 ++++++++++++++++++++++++++ src/libbpf_probes.c | 242 ++++++++++++++++++++++++++++++++++++++++++++ src/libbpf_util.h | 30 ++++++ src/netlink.c | 85 ++++++++++++++++ 11 files changed, 798 insertions(+), 177 deletions(-) create mode 100644 src/libbpf.map create mode 100644 src/libbpf_probes.c create mode 100644 src/libbpf_util.h diff --git a/src/README.rst b/src/README.rst index 056f383..607aae4 100644 --- a/src/README.rst +++ b/src/README.rst @@ -132,6 +132,20 @@ For example, if current state of ``libbpf.map`` is: Format of version script and ways to handle ABI changes, including incompatible ones, described in details in [1]. +Stand-alone build +================= + +Under https://github.com/libbpf/libbpf there is a (semi-)automated +mirror of the mainline's version of libbpf for a stand-alone build. + +However, all changes to libbpf's code base must be upstreamed through +the mainline kernel tree. + +License +======= + +libbpf is dual-licensed under LGPL 2.1 and BSD 2-Clause. + Links ===== diff --git a/src/bpf.c b/src/bpf.c index 3caaa34..3defad7 100644 --- a/src/bpf.c +++ b/src/bpf.c @@ -65,6 +65,17 @@ static inline int sys_bpf(enum bpf_cmd cmd, union bpf_attr *attr, return syscall(__NR_bpf, cmd, attr, size); } +static inline int sys_bpf_prog_load(union bpf_attr *attr, unsigned int size) +{ + int fd; + + do { + fd = sys_bpf(BPF_PROG_LOAD, attr, size); + } while (fd < 0 && errno == EAGAIN); + + return fd; +} + int bpf_create_map_xattr(const struct bpf_create_map_attr *create_attr) { __u32 name_len = create_attr->name ? strlen(create_attr->name) : 0; @@ -232,7 +243,7 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr, memcpy(attr.prog_name, load_attr->name, min(name_len, BPF_OBJ_NAME_LEN - 1)); - fd = sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr)); + fd = sys_bpf_prog_load(&attr, sizeof(attr)); if (fd >= 0) return fd; @@ -269,7 +280,7 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr, break; } - fd = sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr)); + fd = sys_bpf_prog_load(&attr, sizeof(attr)); if (fd >= 0) goto done; @@ -283,7 +294,7 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr, attr.log_size = log_buf_sz; attr.log_level = 1; log_buf[0] = 0; - fd = sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr)); + fd = sys_bpf_prog_load(&attr, sizeof(attr)); done: free(finfo); free(linfo); @@ -328,7 +339,7 @@ int bpf_verify_program(enum bpf_prog_type type, const struct bpf_insn *insns, attr.kern_version = kern_version; attr.prog_flags = prog_flags; - return sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr)); + return sys_bpf_prog_load(&attr, sizeof(attr)); } int bpf_map_update_elem(int fd, const void *key, const void *value, @@ -357,6 +368,19 @@ int bpf_map_lookup_elem(int fd, const void *key, void *value) return sys_bpf(BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr)); } +int bpf_map_lookup_elem_flags(int fd, const void *key, void *value, __u64 flags) +{ + union bpf_attr attr; + + bzero(&attr, sizeof(attr)); + attr.map_fd = fd; + attr.key = ptr_to_u64(key); + attr.value = ptr_to_u64(value); + attr.flags = flags; + + return sys_bpf(BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr)); +} + int bpf_map_lookup_and_delete_elem(int fd, const void *key, void *value) { union bpf_attr attr; diff --git a/src/bpf.h b/src/bpf.h index 8f09de4..ed09eed 100644 --- a/src/bpf.h +++ b/src/bpf.h @@ -110,6 +110,8 @@ LIBBPF_API int bpf_map_update_elem(int fd, const void *key, const void *value, __u64 flags); LIBBPF_API int bpf_map_lookup_elem(int fd, const void *key, void *value); +LIBBPF_API int bpf_map_lookup_elem_flags(int fd, const void *key, void *value, + __u64 flags); LIBBPF_API int bpf_map_lookup_and_delete_elem(int fd, const void *key, void *value); LIBBPF_API int bpf_map_delete_elem(int fd, const void *key); diff --git a/src/btf.c b/src/btf.c index d682d3b..7ec0463 100644 --- a/src/btf.c +++ b/src/btf.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) /* Copyright (c) 2018 Facebook */ +#include #include #include #include @@ -9,8 +10,9 @@ #include #include "btf.h" #include "bpf.h" +#include "libbpf.h" +#include "libbpf_util.h" -#define elog(fmt, ...) { if (err_log) err_log(fmt, ##__VA_ARGS__); } #define max(a, b) ((a) > (b) ? (a) : (b)) #define min(a, b) ((a) < (b) ? (a) : (b)) @@ -107,54 +109,54 @@ static int btf_add_type(struct btf *btf, struct btf_type *t) return 0; } -static int btf_parse_hdr(struct btf *btf, btf_print_fn_t err_log) +static int btf_parse_hdr(struct btf *btf) { const struct btf_header *hdr = btf->hdr; __u32 meta_left; if (btf->data_size < sizeof(struct btf_header)) { - elog("BTF header not found\n"); + pr_debug("BTF header not found\n"); return -EINVAL; } if (hdr->magic != BTF_MAGIC) { - elog("Invalid BTF magic:%x\n", hdr->magic); + pr_debug("Invalid BTF magic:%x\n", hdr->magic); return -EINVAL; } if (hdr->version != BTF_VERSION) { - elog("Unsupported BTF version:%u\n", hdr->version); + pr_debug("Unsupported BTF version:%u\n", hdr->version); return -ENOTSUP; } if (hdr->flags) { - elog("Unsupported BTF flags:%x\n", hdr->flags); + pr_debug("Unsupported BTF flags:%x\n", hdr->flags); return -ENOTSUP; } meta_left = btf->data_size - sizeof(*hdr); if (!meta_left) { - elog("BTF has no data\n"); + pr_debug("BTF has no data\n"); return -EINVAL; } if (meta_left < hdr->type_off) { - elog("Invalid BTF type section offset:%u\n", hdr->type_off); + pr_debug("Invalid BTF type section offset:%u\n", hdr->type_off); return -EINVAL; } if (meta_left < hdr->str_off) { - elog("Invalid BTF string section offset:%u\n", hdr->str_off); + pr_debug("Invalid BTF string section offset:%u\n", hdr->str_off); return -EINVAL; } if (hdr->type_off >= hdr->str_off) { - elog("BTF type section offset >= string section offset. No type?\n"); + pr_debug("BTF type section offset >= string section offset. No type?\n"); return -EINVAL; } if (hdr->type_off & 0x02) { - elog("BTF type section is not aligned to 4 bytes\n"); + pr_debug("BTF type section is not aligned to 4 bytes\n"); return -EINVAL; } @@ -163,7 +165,7 @@ static int btf_parse_hdr(struct btf *btf, btf_print_fn_t err_log) return 0; } -static int btf_parse_str_sec(struct btf *btf, btf_print_fn_t err_log) +static int btf_parse_str_sec(struct btf *btf) { const struct btf_header *hdr = btf->hdr; const char *start = btf->nohdr_data + hdr->str_off; @@ -171,7 +173,7 @@ static int btf_parse_str_sec(struct btf *btf, btf_print_fn_t err_log) if (!hdr->str_len || hdr->str_len - 1 > BTF_MAX_NAME_OFFSET || start[0] || end[-1]) { - elog("Invalid BTF string section\n"); + pr_debug("Invalid BTF string section\n"); return -EINVAL; } @@ -180,7 +182,7 @@ static int btf_parse_str_sec(struct btf *btf, btf_print_fn_t err_log) return 0; } -static int btf_parse_type_sec(struct btf *btf, btf_print_fn_t err_log) +static int btf_parse_type_sec(struct btf *btf) { struct btf_header *hdr = btf->hdr; void *nohdr_data = btf->nohdr_data; @@ -219,7 +221,7 @@ static int btf_parse_type_sec(struct btf *btf, btf_print_fn_t err_log) case BTF_KIND_RESTRICT: break; default: - elog("Unsupported BTF_KIND:%u\n", + pr_debug("Unsupported BTF_KIND:%u\n", BTF_INFO_KIND(t->info)); return -EINVAL; } @@ -363,7 +365,7 @@ void btf__free(struct btf *btf) free(btf); } -struct btf *btf__new(__u8 *data, __u32 size, btf_print_fn_t err_log) +struct btf *btf__new(__u8 *data, __u32 size) { __u32 log_buf_size = 0; char *log_buf = NULL; @@ -376,16 +378,15 @@ struct btf *btf__new(__u8 *data, __u32 size, btf_print_fn_t err_log) btf->fd = -1; - if (err_log) { - log_buf = malloc(BPF_LOG_BUF_SIZE); - if (!log_buf) { - err = -ENOMEM; - goto done; - } - *log_buf = 0; - log_buf_size = BPF_LOG_BUF_SIZE; + log_buf = malloc(BPF_LOG_BUF_SIZE); + if (!log_buf) { + err = -ENOMEM; + goto done; } + *log_buf = 0; + log_buf_size = BPF_LOG_BUF_SIZE; + btf->data = malloc(size); if (!btf->data) { err = -ENOMEM; @@ -400,21 +401,21 @@ struct btf *btf__new(__u8 *data, __u32 size, btf_print_fn_t err_log) if (btf->fd == -1) { err = -errno; - elog("Error loading BTF: %s(%d)\n", strerror(errno), errno); + pr_warning("Error loading BTF: %s(%d)\n", strerror(errno), errno); if (log_buf && *log_buf) - elog("%s\n", log_buf); + pr_warning("%s\n", log_buf); goto done; } - err = btf_parse_hdr(btf, err_log); + err = btf_parse_hdr(btf); if (err) goto done; - err = btf_parse_str_sec(btf, err_log); + err = btf_parse_str_sec(btf); if (err) goto done; - err = btf_parse_type_sec(btf, err_log); + err = btf_parse_type_sec(btf); done: free(log_buf); @@ -491,7 +492,7 @@ int btf__get_from_id(__u32 id, struct btf **btf) goto exit_free; } - *btf = btf__new((__u8 *)(long)btf_info.btf, btf_info.btf_size, NULL); + *btf = btf__new((__u8 *)(long)btf_info.btf, btf_info.btf_size); if (IS_ERR(*btf)) { err = PTR_ERR(*btf); *btf = NULL; @@ -504,6 +505,78 @@ exit_free: return err; } +int btf__get_map_kv_tids(const struct btf *btf, char *map_name, + __u32 expected_key_size, __u32 expected_value_size, + __u32 *key_type_id, __u32 *value_type_id) +{ + const struct btf_type *container_type; + const struct btf_member *key, *value; + const size_t max_name = 256; + char container_name[max_name]; + __s64 key_size, value_size; + __s32 container_id; + + if (snprintf(container_name, max_name, "____btf_map_%s", map_name) == + max_name) { + pr_warning("map:%s length of '____btf_map_%s' is too long\n", + map_name, map_name); + return -EINVAL; + } + + container_id = btf__find_by_name(btf, container_name); + if (container_id < 0) { + pr_warning("map:%s container_name:%s cannot be found in BTF. Missing BPF_ANNOTATE_KV_PAIR?\n", + map_name, container_name); + return container_id; + } + + container_type = btf__type_by_id(btf, container_id); + if (!container_type) { + pr_warning("map:%s cannot find BTF type for container_id:%u\n", + map_name, container_id); + return -EINVAL; + } + + if (BTF_INFO_KIND(container_type->info) != BTF_KIND_STRUCT || + BTF_INFO_VLEN(container_type->info) < 2) { + pr_warning("map:%s container_name:%s is an invalid container struct\n", + map_name, container_name); + return -EINVAL; + } + + key = (struct btf_member *)(container_type + 1); + value = key + 1; + + key_size = btf__resolve_size(btf, key->type); + if (key_size < 0) { + pr_warning("map:%s invalid BTF key_type_size\n", map_name); + return key_size; + } + + if (expected_key_size != key_size) { + pr_warning("map:%s btf_key_type_size:%u != map_def_key_size:%u\n", + map_name, (__u32)key_size, expected_key_size); + return -EINVAL; + } + + value_size = btf__resolve_size(btf, value->type); + if (value_size < 0) { + pr_warning("map:%s invalid BTF value_type_size\n", map_name); + return value_size; + } + + if (expected_value_size != value_size) { + pr_warning("map:%s btf_value_type_size:%u != map_def_value_size:%u\n", + map_name, (__u32)value_size, expected_value_size); + return -EINVAL; + } + + *key_type_id = key->type; + *value_type_id = value->type; + + return 0; +} + struct btf_ext_sec_copy_param { __u32 off; __u32 len; @@ -514,8 +587,7 @@ struct btf_ext_sec_copy_param { static int btf_ext_copy_info(struct btf_ext *btf_ext, __u8 *data, __u32 data_size, - struct btf_ext_sec_copy_param *ext_sec, - btf_print_fn_t err_log) + struct btf_ext_sec_copy_param *ext_sec) { const struct btf_ext_header *hdr = (struct btf_ext_header *)data; const struct btf_ext_info_sec *sinfo; @@ -529,14 +601,14 @@ static int btf_ext_copy_info(struct btf_ext *btf_ext, data_size -= hdr->hdr_len; if (ext_sec->off & 0x03) { - elog(".BTF.ext %s section is not aligned to 4 bytes\n", + pr_debug(".BTF.ext %s section is not aligned to 4 bytes\n", ext_sec->desc); return -EINVAL; } if (data_size < ext_sec->off || ext_sec->len > data_size - ext_sec->off) { - elog("%s section (off:%u len:%u) is beyond the end of the ELF section .BTF.ext\n", + pr_debug("%s section (off:%u len:%u) is beyond the end of the ELF section .BTF.ext\n", ext_sec->desc, ext_sec->off, ext_sec->len); return -EINVAL; } @@ -546,7 +618,7 @@ static int btf_ext_copy_info(struct btf_ext *btf_ext, /* At least a record size */ if (info_left < sizeof(__u32)) { - elog(".BTF.ext %s record size not found\n", ext_sec->desc); + pr_debug(".BTF.ext %s record size not found\n", ext_sec->desc); return -EINVAL; } @@ -554,7 +626,7 @@ static int btf_ext_copy_info(struct btf_ext *btf_ext, record_size = *(__u32 *)info; if (record_size < ext_sec->min_rec_size || record_size & 0x03) { - elog("%s section in .BTF.ext has invalid record size %u\n", + pr_debug("%s section in .BTF.ext has invalid record size %u\n", ext_sec->desc, record_size); return -EINVAL; } @@ -564,7 +636,7 @@ static int btf_ext_copy_info(struct btf_ext *btf_ext, /* If no records, return failure now so .BTF.ext won't be used. */ if (!info_left) { - elog("%s section in .BTF.ext has no records", ext_sec->desc); + pr_debug("%s section in .BTF.ext has no records", ext_sec->desc); return -EINVAL; } @@ -574,14 +646,14 @@ static int btf_ext_copy_info(struct btf_ext *btf_ext, __u32 num_records; if (info_left < sec_hdrlen) { - elog("%s section header is not found in .BTF.ext\n", + pr_debug("%s section header is not found in .BTF.ext\n", ext_sec->desc); return -EINVAL; } num_records = sinfo->num_info; if (num_records == 0) { - elog("%s section has incorrect num_records in .BTF.ext\n", + pr_debug("%s section has incorrect num_records in .BTF.ext\n", ext_sec->desc); return -EINVAL; } @@ -589,7 +661,7 @@ static int btf_ext_copy_info(struct btf_ext *btf_ext, total_record_size = sec_hdrlen + (__u64)num_records * record_size; if (info_left < total_record_size) { - elog("%s section has incorrect num_records in .BTF.ext\n", + pr_debug("%s section has incorrect num_records in .BTF.ext\n", ext_sec->desc); return -EINVAL; } @@ -610,8 +682,7 @@ static int btf_ext_copy_info(struct btf_ext *btf_ext, } static int btf_ext_copy_func_info(struct btf_ext *btf_ext, - __u8 *data, __u32 data_size, - btf_print_fn_t err_log) + __u8 *data, __u32 data_size) { const struct btf_ext_header *hdr = (struct btf_ext_header *)data; struct btf_ext_sec_copy_param param = { @@ -622,12 +693,11 @@ static int btf_ext_copy_func_info(struct btf_ext *btf_ext, .desc = "func_info" }; - return btf_ext_copy_info(btf_ext, data, data_size, ¶m, err_log); + return btf_ext_copy_info(btf_ext, data, data_size, ¶m); } static int btf_ext_copy_line_info(struct btf_ext *btf_ext, - __u8 *data, __u32 data_size, - btf_print_fn_t err_log) + __u8 *data, __u32 data_size) { const struct btf_ext_header *hdr = (struct btf_ext_header *)data; struct btf_ext_sec_copy_param param = { @@ -638,37 +708,36 @@ static int btf_ext_copy_line_info(struct btf_ext *btf_ext, .desc = "line_info", }; - return btf_ext_copy_info(btf_ext, data, data_size, ¶m, err_log); + return btf_ext_copy_info(btf_ext, data, data_size, ¶m); } -static int btf_ext_parse_hdr(__u8 *data, __u32 data_size, - btf_print_fn_t err_log) +static int btf_ext_parse_hdr(__u8 *data, __u32 data_size) { const struct btf_ext_header *hdr = (struct btf_ext_header *)data; if (data_size < offsetof(struct btf_ext_header, func_info_off) || data_size < hdr->hdr_len) { - elog("BTF.ext header not found"); + pr_debug("BTF.ext header not found"); return -EINVAL; } if (hdr->magic != BTF_MAGIC) { - elog("Invalid BTF.ext magic:%x\n", hdr->magic); + pr_debug("Invalid BTF.ext magic:%x\n", hdr->magic); return -EINVAL; } if (hdr->version != BTF_VERSION) { - elog("Unsupported BTF.ext version:%u\n", hdr->version); + pr_debug("Unsupported BTF.ext version:%u\n", hdr->version); return -ENOTSUP; } if (hdr->flags) { - elog("Unsupported BTF.ext flags:%x\n", hdr->flags); + pr_debug("Unsupported BTF.ext flags:%x\n", hdr->flags); return -ENOTSUP; } if (data_size == hdr->hdr_len) { - elog("BTF.ext has no data\n"); + pr_debug("BTF.ext has no data\n"); return -EINVAL; } @@ -685,12 +754,12 @@ void btf_ext__free(struct btf_ext *btf_ext) free(btf_ext); } -struct btf_ext *btf_ext__new(__u8 *data, __u32 size, btf_print_fn_t err_log) +struct btf_ext *btf_ext__new(__u8 *data, __u32 size) { struct btf_ext *btf_ext; int err; - err = btf_ext_parse_hdr(data, size, err_log); + err = btf_ext_parse_hdr(data, size); if (err) return ERR_PTR(err); @@ -698,13 +767,13 @@ struct btf_ext *btf_ext__new(__u8 *data, __u32 size, btf_print_fn_t err_log) if (!btf_ext) return ERR_PTR(-ENOMEM); - err = btf_ext_copy_func_info(btf_ext, data, size, err_log); + err = btf_ext_copy_func_info(btf_ext, data, size); if (err) { btf_ext__free(btf_ext); return ERR_PTR(err); } - err = btf_ext_copy_line_info(btf_ext, data, size, err_log); + err = btf_ext_copy_line_info(btf_ext, data, size); if (err) { btf_ext__free(btf_ext); return ERR_PTR(err); diff --git a/src/btf.h b/src/btf.h index b0610dc..258c87e 100644 --- a/src/btf.h +++ b/src/btf.h @@ -55,11 +55,8 @@ struct btf_ext_header { __u32 line_info_len; }; -typedef int (*btf_print_fn_t)(const char *, ...) - __attribute__((format(printf, 1, 2))); - LIBBPF_API void btf__free(struct btf *btf); -LIBBPF_API struct btf *btf__new(__u8 *data, __u32 size, btf_print_fn_t err_log); +LIBBPF_API struct btf *btf__new(__u8 *data, __u32 size); LIBBPF_API __s32 btf__find_by_name(const struct btf *btf, const char *type_name); LIBBPF_API const struct btf_type *btf__type_by_id(const struct btf *btf, @@ -69,19 +66,23 @@ LIBBPF_API int btf__resolve_type(const struct btf *btf, __u32 type_id); LIBBPF_API int btf__fd(const struct btf *btf); LIBBPF_API const char *btf__name_by_offset(const struct btf *btf, __u32 offset); LIBBPF_API int btf__get_from_id(__u32 id, struct btf **btf); +LIBBPF_API int btf__get_map_kv_tids(const struct btf *btf, char *map_name, + __u32 expected_key_size, + __u32 expected_value_size, + __u32 *key_type_id, __u32 *value_type_id); -struct btf_ext *btf_ext__new(__u8 *data, __u32 size, btf_print_fn_t err_log); -void btf_ext__free(struct btf_ext *btf_ext); -int btf_ext__reloc_func_info(const struct btf *btf, - const struct btf_ext *btf_ext, - const char *sec_name, __u32 insns_cnt, - void **func_info, __u32 *func_info_len); -int btf_ext__reloc_line_info(const struct btf *btf, - const struct btf_ext *btf_ext, - const char *sec_name, __u32 insns_cnt, - void **line_info, __u32 *cnt); -__u32 btf_ext__func_info_rec_size(const struct btf_ext *btf_ext); -__u32 btf_ext__line_info_rec_size(const struct btf_ext *btf_ext); +LIBBPF_API struct btf_ext *btf_ext__new(__u8 *data, __u32 size); +LIBBPF_API void btf_ext__free(struct btf_ext *btf_ext); +LIBBPF_API int btf_ext__reloc_func_info(const struct btf *btf, + const struct btf_ext *btf_ext, + const char *sec_name, __u32 insns_cnt, + void **func_info, __u32 *cnt); +LIBBPF_API int btf_ext__reloc_line_info(const struct btf *btf, + const struct btf_ext *btf_ext, + const char *sec_name, __u32 insns_cnt, + void **line_info, __u32 *cnt); +LIBBPF_API __u32 btf_ext__func_info_rec_size(const struct btf_ext *btf_ext); +LIBBPF_API __u32 btf_ext__line_info_rec_size(const struct btf_ext *btf_ext); #ifdef __cplusplus } /* extern "C" */ diff --git a/src/libbpf.c b/src/libbpf.c index 169e347..84ca6c2 100644 --- a/src/libbpf.c +++ b/src/libbpf.c @@ -42,6 +42,7 @@ #include "bpf.h" #include "btf.h" #include "str_error.h" +#include "libbpf_util.h" #ifndef EM_BPF #define EM_BPF 247 @@ -53,39 +54,39 @@ #define __printf(a, b) __attribute__((format(printf, a, b))) -__printf(1, 2) -static int __base_pr(const char *format, ...) +__printf(2, 3) +static int __base_pr(enum libbpf_print_level level, const char *format, ...) { va_list args; int err; + if (level == LIBBPF_DEBUG) + return 0; + va_start(args, format); err = vfprintf(stderr, format, args); va_end(args); return err; } -static __printf(1, 2) libbpf_print_fn_t __pr_warning = __base_pr; -static __printf(1, 2) libbpf_print_fn_t __pr_info = __base_pr; -static __printf(1, 2) libbpf_print_fn_t __pr_debug; +static __printf(2, 3) libbpf_print_fn_t __libbpf_pr = __base_pr; -#define __pr(func, fmt, ...) \ -do { \ - if ((func)) \ - (func)("libbpf: " fmt, ##__VA_ARGS__); \ -} while (0) - -#define pr_warning(fmt, ...) __pr(__pr_warning, fmt, ##__VA_ARGS__) -#define pr_info(fmt, ...) __pr(__pr_info, fmt, ##__VA_ARGS__) -#define pr_debug(fmt, ...) __pr(__pr_debug, fmt, ##__VA_ARGS__) - -void libbpf_set_print(libbpf_print_fn_t warn, - libbpf_print_fn_t info, - libbpf_print_fn_t debug) +void libbpf_set_print(libbpf_print_fn_t fn) { - __pr_warning = warn; - __pr_info = info; - __pr_debug = debug; + __libbpf_pr = fn; +} + +__printf(2, 3) +void libbpf_print(enum libbpf_print_level level, const char *format, ...) +{ + va_list args; + + if (!__libbpf_pr) + return; + + va_start(args, format); + __libbpf_pr(level, format, args); + va_end(args); } #define STRERR_BUFSIZE 128 @@ -839,8 +840,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj, int flags) else if (strcmp(name, "maps") == 0) obj->efile.maps_shndx = idx; else if (strcmp(name, BTF_ELF_SEC) == 0) { - obj->btf = btf__new(data->d_buf, data->d_size, - __pr_debug); + obj->btf = btf__new(data->d_buf, data->d_size); if (IS_ERR(obj->btf)) { pr_warning("Error loading ELF section %s: %ld. Ignored and continue.\n", BTF_ELF_SEC, PTR_ERR(obj->btf)); @@ -915,8 +915,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj, int flags) BTF_EXT_ELF_SEC, BTF_ELF_SEC); } else { obj->btf_ext = btf_ext__new(btf_ext_data->d_buf, - btf_ext_data->d_size, - __pr_debug); + btf_ext_data->d_size); if (IS_ERR(obj->btf_ext)) { pr_warning("Error loading ELF section %s: %ld. Ignored and continue.\n", BTF_EXT_ELF_SEC, @@ -1057,72 +1056,18 @@ bpf_program__collect_reloc(struct bpf_program *prog, GElf_Shdr *shdr, static int bpf_map_find_btf_info(struct bpf_map *map, const struct btf *btf) { - const struct btf_type *container_type; - const struct btf_member *key, *value; struct bpf_map_def *def = &map->def; - const size_t max_name = 256; - char container_name[max_name]; - __s64 key_size, value_size; - __s32 container_id; + __u32 key_type_id, value_type_id; + int ret; - if (snprintf(container_name, max_name, "____btf_map_%s", map->name) == - max_name) { - pr_warning("map:%s length of '____btf_map_%s' is too long\n", - map->name, map->name); - return -EINVAL; - } + ret = btf__get_map_kv_tids(btf, map->name, def->key_size, + def->value_size, &key_type_id, + &value_type_id); + if (ret) + return ret; - container_id = btf__find_by_name(btf, container_name); - if (container_id < 0) { - pr_debug("map:%s container_name:%s cannot be found in BTF. Missing BPF_ANNOTATE_KV_PAIR?\n", - map->name, container_name); - return container_id; - } - - container_type = btf__type_by_id(btf, container_id); - if (!container_type) { - pr_warning("map:%s cannot find BTF type for container_id:%u\n", - map->name, container_id); - return -EINVAL; - } - - if (BTF_INFO_KIND(container_type->info) != BTF_KIND_STRUCT || - BTF_INFO_VLEN(container_type->info) < 2) { - pr_warning("map:%s container_name:%s is an invalid container struct\n", - map->name, container_name); - return -EINVAL; - } - - key = (struct btf_member *)(container_type + 1); - value = key + 1; - - key_size = btf__resolve_size(btf, key->type); - if (key_size < 0) { - pr_warning("map:%s invalid BTF key_type_size\n", - map->name); - return key_size; - } - - if (def->key_size != key_size) { - pr_warning("map:%s btf_key_type_size:%u != map_def_key_size:%u\n", - map->name, (__u32)key_size, def->key_size); - return -EINVAL; - } - - value_size = btf__resolve_size(btf, value->type); - if (value_size < 0) { - pr_warning("map:%s invalid BTF value_type_size\n", map->name); - return value_size; - } - - if (def->value_size != value_size) { - pr_warning("map:%s btf_value_type_size:%u != map_def_value_size:%u\n", - map->name, (__u32)value_size, def->value_size); - return -EINVAL; - } - - map->btf_key_type_id = key->type; - map->btf_value_type_id = value->type; + map->btf_key_type_id = key_type_id; + map->btf_value_type_id = value_type_id; return 0; } @@ -2667,9 +2612,38 @@ static const struct { #undef BPF_EAPROG_SEC #undef BPF_APROG_COMPAT +#define MAX_TYPE_NAME_SIZE 32 + +static char *libbpf_get_type_names(bool attach_type) +{ + int i, len = ARRAY_SIZE(section_names) * MAX_TYPE_NAME_SIZE; + char *buf; + + buf = malloc(len); + if (!buf) + return NULL; + + buf[0] = '\0'; + /* Forge string buf with all available names */ + for (i = 0; i < ARRAY_SIZE(section_names); i++) { + if (attach_type && !section_names[i].is_attachable) + continue; + + if (strlen(buf) + strlen(section_names[i].sec) + 2 > len) { + free(buf); + return NULL; + } + strcat(buf, " "); + strcat(buf, section_names[i].sec); + } + + return buf; +} + int libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type, enum bpf_attach_type *expected_attach_type) { + char *type_names; int i; if (!name) @@ -2682,12 +2656,20 @@ int libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type, *expected_attach_type = section_names[i].expected_attach_type; return 0; } + pr_warning("failed to guess program type based on ELF section name '%s'\n", name); + type_names = libbpf_get_type_names(false); + if (type_names != NULL) { + pr_info("supported section(type) names are:%s\n", type_names); + free(type_names); + } + return -EINVAL; } int libbpf_attach_type_by_name(const char *name, enum bpf_attach_type *attach_type) { + char *type_names; int i; if (!name) @@ -2701,6 +2683,13 @@ int libbpf_attach_type_by_name(const char *name, *attach_type = section_names[i].attach_type; return 0; } + pr_warning("failed to guess attach type based on ELF section name '%s'\n", name); + type_names = libbpf_get_type_names(true); + if (type_names != NULL) { + pr_info("attachable section(type) names are:%s\n", type_names); + free(type_names); + } + return -EINVAL; } @@ -2840,6 +2829,12 @@ bpf_object__find_map_by_name(struct bpf_object *obj, const char *name) return NULL; } +int +bpf_object__find_map_fd_by_name(struct bpf_object *obj, const char *name) +{ + return bpf_map__fd(bpf_object__find_map_by_name(obj, name)); +} + struct bpf_map * bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset) { @@ -2907,8 +2902,6 @@ int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, err = bpf_program__identify_section(prog, &prog_type, &expected_attach_type); if (err < 0) { - pr_warning("failed to guess program type based on section name %s\n", - prog->section_name); bpf_object__close(obj); return -EINVAL; } diff --git a/src/libbpf.h b/src/libbpf.h index 5f68d7b..19dbc1b 100644 --- a/src/libbpf.h +++ b/src/libbpf.h @@ -47,17 +47,17 @@ enum libbpf_errno { LIBBPF_API int libbpf_strerror(int err, char *buf, size_t size); -/* - * __printf is defined in include/linux/compiler-gcc.h. However, - * it would be better if libbpf.h didn't depend on Linux header files. - * So instead of __printf, here we use gcc attribute directly. - */ -typedef int (*libbpf_print_fn_t)(const char *, ...) - __attribute__((format(printf, 1, 2))); +enum libbpf_print_level { + LIBBPF_WARN, + LIBBPF_INFO, + LIBBPF_DEBUG, +}; -LIBBPF_API void libbpf_set_print(libbpf_print_fn_t warn, - libbpf_print_fn_t info, - libbpf_print_fn_t debug); +typedef int (*libbpf_print_fn_t)(enum libbpf_print_level level, + const char *, ...) + __attribute__((format(printf, 2, 3))); + +LIBBPF_API void libbpf_set_print(libbpf_print_fn_t fn); /* Hide internal to user */ struct bpf_object; @@ -264,6 +264,9 @@ struct bpf_map; LIBBPF_API struct bpf_map * bpf_object__find_map_by_name(struct bpf_object *obj, const char *name); +LIBBPF_API int +bpf_object__find_map_fd_by_name(struct bpf_object *obj, const char *name); + /* * Get bpf_map through the offset of corresponding struct bpf_map_def * in the BPF object file. @@ -314,6 +317,7 @@ LIBBPF_API int bpf_prog_load(const char *file, enum bpf_prog_type type, struct bpf_object **pobj, int *prog_fd); LIBBPF_API int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags); +LIBBPF_API int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags); enum bpf_perf_event_ret { LIBBPF_PERF_EVENT_DONE = 0, @@ -355,6 +359,20 @@ LIBBPF_API const struct bpf_line_info * bpf_prog_linfo__lfind(const struct bpf_prog_linfo *prog_linfo, __u32 insn_off, __u32 nr_skip); +/* + * Probe for supported system features + * + * Note that running many of these probes in a short amount of time can cause + * the kernel to reach the maximal size of lockable memory allowed for the + * user, causing subsequent probes to fail. In this case, the caller may want + * to adjust that limit with setrlimit(). + */ +LIBBPF_API bool bpf_probe_prog_type(enum bpf_prog_type prog_type, + __u32 ifindex); +LIBBPF_API bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex); +LIBBPF_API bool bpf_probe_helper(enum bpf_func_id id, + enum bpf_prog_type prog_type, __u32 ifindex); + #ifdef __cplusplus } /* extern "C" */ #endif diff --git a/src/libbpf.map b/src/libbpf.map new file mode 100644 index 0000000..7990e85 --- /dev/null +++ b/src/libbpf.map @@ -0,0 +1,143 @@ +LIBBPF_0.0.1 { + global: + bpf_btf_get_fd_by_id; + bpf_create_map; + bpf_create_map_in_map; + bpf_create_map_in_map_node; + bpf_create_map_name; + bpf_create_map_node; + bpf_create_map_xattr; + bpf_load_btf; + bpf_load_program; + bpf_load_program_xattr; + bpf_map__btf_key_type_id; + bpf_map__btf_value_type_id; + bpf_map__def; + bpf_map__fd; + bpf_map__is_offload_neutral; + bpf_map__name; + bpf_map__next; + bpf_map__pin; + bpf_map__prev; + bpf_map__priv; + bpf_map__reuse_fd; + bpf_map__set_ifindex; + bpf_map__set_inner_map_fd; + bpf_map__set_priv; + bpf_map__unpin; + bpf_map_delete_elem; + bpf_map_get_fd_by_id; + bpf_map_get_next_id; + bpf_map_get_next_key; + bpf_map_lookup_and_delete_elem; + bpf_map_lookup_elem; + bpf_map_update_elem; + bpf_obj_get; + bpf_obj_get_info_by_fd; + bpf_obj_pin; + bpf_object__btf_fd; + bpf_object__close; + bpf_object__find_map_by_name; + bpf_object__find_map_by_offset; + bpf_object__find_program_by_title; + bpf_object__kversion; + bpf_object__load; + bpf_object__name; + bpf_object__next; + bpf_object__open; + bpf_object__open_buffer; + bpf_object__open_xattr; + bpf_object__pin; + bpf_object__pin_maps; + bpf_object__pin_programs; + bpf_object__priv; + bpf_object__set_priv; + bpf_object__unload; + bpf_object__unpin_maps; + bpf_object__unpin_programs; + bpf_perf_event_read_simple; + bpf_prog_attach; + bpf_prog_detach; + bpf_prog_detach2; + bpf_prog_get_fd_by_id; + bpf_prog_get_next_id; + bpf_prog_load; + bpf_prog_load_xattr; + bpf_prog_query; + bpf_prog_test_run; + bpf_prog_test_run_xattr; + bpf_program__fd; + bpf_program__is_kprobe; + bpf_program__is_perf_event; + bpf_program__is_raw_tracepoint; + bpf_program__is_sched_act; + bpf_program__is_sched_cls; + bpf_program__is_socket_filter; + bpf_program__is_tracepoint; + bpf_program__is_xdp; + bpf_program__load; + bpf_program__next; + bpf_program__nth_fd; + bpf_program__pin; + bpf_program__pin_instance; + bpf_program__prev; + bpf_program__priv; + bpf_program__set_expected_attach_type; + bpf_program__set_ifindex; + bpf_program__set_kprobe; + bpf_program__set_perf_event; + bpf_program__set_prep; + bpf_program__set_priv; + bpf_program__set_raw_tracepoint; + bpf_program__set_sched_act; + bpf_program__set_sched_cls; + bpf_program__set_socket_filter; + bpf_program__set_tracepoint; + bpf_program__set_type; + bpf_program__set_xdp; + bpf_program__title; + bpf_program__unload; + bpf_program__unpin; + bpf_program__unpin_instance; + bpf_prog_linfo__free; + bpf_prog_linfo__new; + bpf_prog_linfo__lfind_addr_func; + bpf_prog_linfo__lfind; + bpf_raw_tracepoint_open; + bpf_set_link_xdp_fd; + bpf_task_fd_query; + bpf_verify_program; + btf__fd; + btf__find_by_name; + btf__free; + btf__get_from_id; + btf__name_by_offset; + btf__new; + btf__resolve_size; + btf__resolve_type; + btf__type_by_id; + libbpf_attach_type_by_name; + libbpf_get_error; + libbpf_prog_type_by_name; + libbpf_set_print; + libbpf_strerror; + local: + *; +}; + +LIBBPF_0.0.2 { + global: + bpf_probe_helper; + bpf_probe_map_type; + bpf_probe_prog_type; + bpf_map_lookup_elem_flags; + bpf_object__find_map_fd_by_name; + bpf_get_link_xdp_id; + btf__get_map_kv_tids; + btf_ext__free; + btf_ext__func_info_rec_size; + btf_ext__line_info_rec_size; + btf_ext__new; + btf_ext__reloc_func_info; + btf_ext__reloc_line_info; +} LIBBPF_0.0.1; diff --git a/src/libbpf_probes.c b/src/libbpf_probes.c new file mode 100644 index 0000000..8c3a1c0 --- /dev/null +++ b/src/libbpf_probes.c @@ -0,0 +1,242 @@ +// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) +/* Copyright (c) 2019 Netronome Systems, Inc. */ + +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#include "bpf.h" +#include "libbpf.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_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_LWT_SEG6LOCAL: + case BPF_PROG_TYPE_LIRC_MODE2: + case BPF_PROG_TYPE_SK_REUSEPORT: + case BPF_PROG_TYPE_FLOW_DISSECTOR: + 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; +} + +bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex) +{ + int key_size, value_size, max_entries, map_flags; + struct bpf_create_map_attr attr = {}; + int 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_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_SOCKMAP: + case BPF_MAP_TYPE_CPUMAP: + case BPF_MAP_TYPE_XSKMAP: + case BPF_MAP_TYPE_SOCKHASH: + case BPF_MAP_TYPE_REUSEPORT_SOCKARRAY: + 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; + + fd = bpf_create_map_xattr(&attr); + } + if (fd >= 0) + close(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; +} diff --git a/src/libbpf_util.h b/src/libbpf_util.h new file mode 100644 index 0000000..81ecda0 --- /dev/null +++ b/src/libbpf_util.h @@ -0,0 +1,30 @@ +/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ +/* Copyright (c) 2019 Facebook */ + +#ifndef __LIBBPF_LIBBPF_UTIL_H +#define __LIBBPF_LIBBPF_UTIL_H + +#include + +#ifdef __cplusplus +extern "C" { +#endif + +extern void libbpf_print(enum libbpf_print_level level, + const char *format, ...) + __attribute__((format(printf, 2, 3))); + +#define __pr(level, fmt, ...) \ +do { \ + libbpf_print(level, "libbpf: " fmt, ##__VA_ARGS__); \ +} while (0) + +#define pr_warning(fmt, ...) __pr(LIBBPF_WARN, fmt, ##__VA_ARGS__) +#define pr_info(fmt, ...) __pr(LIBBPF_INFO, fmt, ##__VA_ARGS__) +#define pr_debug(fmt, ...) __pr(LIBBPF_DEBUG, fmt, ##__VA_ARGS__) + +#ifdef __cplusplus +} /* extern "C" */ +#endif + +#endif diff --git a/src/netlink.c b/src/netlink.c index 0ce67ae..ce3ec81 100644 --- a/src/netlink.c +++ b/src/netlink.c @@ -21,6 +21,12 @@ typedef int (*__dump_nlmsg_t)(struct nlmsghdr *nlmsg, libbpf_dump_nlmsg_t, void *cookie); +struct xdp_id_md { + int ifindex; + __u32 flags; + __u32 id; +}; + int libbpf_netlink_open(__u32 *nl_pid) { struct sockaddr_nl sa; @@ -196,6 +202,85 @@ static int __dump_link_nlmsg(struct nlmsghdr *nlh, return dump_link_nlmsg(cookie, ifi, tb); } +static unsigned char get_xdp_id_attr(unsigned char mode, __u32 flags) +{ + if (mode != XDP_ATTACHED_MULTI) + return IFLA_XDP_PROG_ID; + if (flags & XDP_FLAGS_DRV_MODE) + return IFLA_XDP_DRV_PROG_ID; + if (flags & XDP_FLAGS_HW_MODE) + return IFLA_XDP_HW_PROG_ID; + if (flags & XDP_FLAGS_SKB_MODE) + return IFLA_XDP_SKB_PROG_ID; + + return IFLA_XDP_UNSPEC; +} + +static int get_xdp_id(void *cookie, void *msg, struct nlattr **tb) +{ + struct nlattr *xdp_tb[IFLA_XDP_MAX + 1]; + struct xdp_id_md *xdp_id = cookie; + struct ifinfomsg *ifinfo = msg; + unsigned char mode, xdp_attr; + int ret; + + if (xdp_id->ifindex && xdp_id->ifindex != ifinfo->ifi_index) + return 0; + + if (!tb[IFLA_XDP]) + return 0; + + ret = libbpf_nla_parse_nested(xdp_tb, IFLA_XDP_MAX, tb[IFLA_XDP], NULL); + if (ret) + return ret; + + if (!xdp_tb[IFLA_XDP_ATTACHED]) + return 0; + + mode = libbpf_nla_getattr_u8(xdp_tb[IFLA_XDP_ATTACHED]); + if (mode == XDP_ATTACHED_NONE) + return 0; + + xdp_attr = get_xdp_id_attr(mode, xdp_id->flags); + if (!xdp_attr || !xdp_tb[xdp_attr]) + return 0; + + xdp_id->id = libbpf_nla_getattr_u32(xdp_tb[xdp_attr]); + + return 0; +} + +int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags) +{ + struct xdp_id_md xdp_id = {}; + int sock, ret; + __u32 nl_pid; + __u32 mask; + + if (flags & ~XDP_FLAGS_MASK) + return -EINVAL; + + /* Check whether the single {HW,DRV,SKB} mode is set */ + flags &= (XDP_FLAGS_SKB_MODE | XDP_FLAGS_DRV_MODE | XDP_FLAGS_HW_MODE); + mask = flags - 1; + if (flags && flags & mask) + return -EINVAL; + + sock = libbpf_netlink_open(&nl_pid); + if (sock < 0) + return sock; + + xdp_id.ifindex = ifindex; + xdp_id.flags = flags; + + ret = libbpf_nl_get_link(sock, nl_pid, get_xdp_id, &xdp_id); + if (!ret) + *prog_id = xdp_id.id; + + close(sock); + return ret; +} + int libbpf_nl_get_link(int sock, unsigned int nl_pid, libbpf_dump_nlmsg_t dump_link_nlmsg, void *cookie) {