Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752608AbbFLFga (ORCPT ); Fri, 12 Jun 2015 01:36:30 -0400 Received: from szxga01-in.huawei.com ([58.251.152.64]:26683 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751606AbbFLFg1 (ORCPT ); Fri, 12 Jun 2015 01:36:27 -0400 From: Wang Nan To: , , , , , , , , , , CC: , , , , Subject: [RFC PATCH v7 08/37] bpf tools: Collect version and license from ELF sections Date: Fri, 12 Jun 2015 05:35:16 +0000 Message-ID: <1434087345-127225-9-git-send-email-wangnan0@huawei.com> X-Mailer: git-send-email 1.8.3.4 In-Reply-To: <1434087345-127225-1-git-send-email-wangnan0@huawei.com> References: <1434087345-127225-1-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.107.197.200] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3244 Lines: 118 Expand bpf_obj_elf_collect() to collect license and kernel version information in eBPF object file. eBPF object file should have a section named 'license', which contains a string. It should also have a section named 'version', contains a u32 LINUX_VERSION_CODE. bpf_obj_validate() is introduced to validate object file after loaded. Currently it only check existance of 'version' section. Signed-off-by: Wang Nan Acked-by: Alexei Starovoitov --- tools/lib/bpf/libbpf.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 1c4da03..3bd183c 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -78,6 +79,8 @@ void libbpf_set_print(libbpf_print_fn_t warn, #endif struct bpf_object { + char license[64]; + u32 kern_version; /* * Information when doing elf related work. Only valid if fd * is valid. @@ -220,6 +223,32 @@ mismatch: return -EINVAL; } +static int +bpf_object__init_license(struct bpf_object *obj, + void *data, size_t size) +{ + memcpy(obj->license, data, + min(size, sizeof(obj->license) - 1)); + pr_debug("license of %s is %s\n", obj->path, obj->license); + return 0; +} + +static int +bpf_object__init_kversion(struct bpf_object *obj, + void *data, size_t size) +{ + u32 kver; + if (size != sizeof(kver)) { + pr_warning("invalid kver section in %s\n", obj->path); + return -EINVAL; + } + memcpy(&kver, data, sizeof(kver)); + obj->kern_version = kver; + pr_debug("kernel version of %s is %x\n", obj->path, + obj->kern_version); + return 0; +} + static int bpf_object__elf_collect(struct bpf_object *obj) { Elf *elf = obj->efile.elf; @@ -266,11 +295,32 @@ static int bpf_object__elf_collect(struct bpf_object *obj) name, (unsigned long)data->d_size, (int)sh.sh_link, (unsigned long)sh.sh_flags, (int)sh.sh_type); + + if (strcmp(name, "license") == 0) + err = bpf_object__init_license(obj, + data->d_buf, + data->d_size); + else if (strcmp(name, "version") == 0) + err = bpf_object__init_kversion(obj, + data->d_buf, + data->d_size); + if (err) + goto out; } out: return err; } +static int bpf_object__validate(struct bpf_object *obj) +{ + if (obj->kern_version == 0) { + pr_warning("%s doesn't provide kernel version\n", + obj->path); + return -EINVAL; + } + return 0; +} + static struct bpf_object * __bpf_object__open(const char *path, void *obj_buf, size_t obj_buf_sz) { @@ -291,6 +341,8 @@ __bpf_object__open(const char *path, void *obj_buf, size_t obj_buf_sz) goto out; if (bpf_object__elf_collect(obj)) goto out; + if (bpf_object__validate(obj)) + goto out; bpf_object__elf_finish(obj); return obj; -- 1.8.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/