[PATCH v5 bpf-next 09/13] libbpf: add bpf_token_create() API
From: Andrii Nakryiko <andrii@kernel.org>
Date: 2023-09-19 21:49:05
Also in:
bpf, linux-fsdevel, linux-security-module
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [library] (libbpf), the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Linus Torvalds
Add low-level wrapper API for BPF_TOKEN_CREATE command in bpf() syscall. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> --- tools/lib/bpf/bpf.c | 19 +++++++++++++++++++ tools/lib/bpf/bpf.h | 28 ++++++++++++++++++++++++++++ tools/lib/bpf/libbpf.map | 1 + 3 files changed, 48 insertions(+)
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index b0f1913763a3..593ff9ea120d 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c@@ -1271,3 +1271,22 @@ int bpf_prog_bind_map(int prog_fd, int map_fd, ret = sys_bpf(BPF_PROG_BIND_MAP, &attr, attr_sz); return libbpf_err_errno(ret); } + +int bpf_token_create(int bpffs_path_fd, const char *bpffs_pathname, + struct bpf_token_create_opts *opts) +{ + const size_t attr_sz = offsetofend(union bpf_attr, token_create); + union bpf_attr attr; + int fd; + + if (!OPTS_VALID(opts, bpf_token_create_opts)) + return libbpf_err(-EINVAL); + + memset(&attr, 0, attr_sz); + attr.token_create.bpffs_path_fd = bpffs_path_fd; + attr.token_create.bpffs_pathname = ptr_to_u64(bpffs_pathname); + attr.token_create.flags = OPTS_GET(opts, flags, 0); + + fd = sys_bpf_fd(BPF_TOKEN_CREATE, &attr, attr_sz); + return libbpf_err_errno(fd); +}
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 74c2887cfd24..a5ddb0393fee 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h@@ -635,6 +635,34 @@ struct bpf_test_run_opts { LIBBPF_API int bpf_prog_test_run_opts(int prog_fd, struct bpf_test_run_opts *opts); +struct bpf_token_create_opts { + size_t sz; /* size of this struct for forward/backward compatibility */ + __u32 flags; + size_t :0; +}; +#define bpf_token_create_opts__last_field flags + +/** + * @brief **bpf_token_create()** creates a new instance of BPF token derived + * from specified BPF FS mount point. + * + * BPF token created with this API can be passed to bpf() syscall for + * commands like BPF_PROG_LOAD, BPF_MAP_CREATE, etc. + * + * @param bpffs_path_fd O_PATH FD (see man 2 openat() for semantics) specifying, + * in combination with *bpffs_pathname*, BPF FS mount from which to derive + * a BPF token instance. + * @param pin_pathname absolute or relative path specifying,in combination + * with *bpffs_pathname*, BPF FS mount from which to derive a BPF token + * instance. + * @param opts optional BPF token creation options, can be NULL + * + * @return BPF token FD > 0, on success; negative error code, otherwise (errno + * is also set to the error code) + */ +LIBBPF_API int bpf_token_create(int bpffs_path_fd, const char *bpffs_pathname, + struct bpf_token_create_opts *opts); + #ifdef __cplusplus } /* extern "C" */ #endif
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index 57712321490f..c45c28a5e14c 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map@@ -400,4 +400,5 @@ LIBBPF_1.3.0 { bpf_program__attach_netfilter; bpf_program__attach_tcx; bpf_program__attach_uprobe_multi; + bpf_token_create; } LIBBPF_1.2.0;
--
2.34.1