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-rw-r--r--tools/lib/bpf/nlattr.h106
1 files changed, 106 insertions, 0 deletions
diff --git a/tools/lib/bpf/nlattr.h b/tools/lib/bpf/nlattr.h
new file mode 100644
index 000000000..6cc3ac916
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+++ b/tools/lib/bpf/nlattr.h
@@ -0,0 +1,106 @@
+/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
+
+/*
+ * NETLINK Netlink attributes
+ *
+ * Copyright (c) 2003-2013 Thomas Graf <tgraf@suug.ch>
+ */
+
+#ifndef __LIBBPF_NLATTR_H
+#define __LIBBPF_NLATTR_H
+
+#include <stdint.h>
+#include <linux/netlink.h>
+/* avoid multiple definition of netlink features */
+#define __LINUX_NETLINK_H
+
+/**
+ * Standard attribute types to specify validation policy
+ */
+enum {
+ LIBBPF_NLA_UNSPEC, /**< Unspecified type, binary data chunk */
+ LIBBPF_NLA_U8, /**< 8 bit integer */
+ LIBBPF_NLA_U16, /**< 16 bit integer */
+ LIBBPF_NLA_U32, /**< 32 bit integer */
+ LIBBPF_NLA_U64, /**< 64 bit integer */
+ LIBBPF_NLA_STRING, /**< NUL terminated character string */
+ LIBBPF_NLA_FLAG, /**< Flag */
+ LIBBPF_NLA_MSECS, /**< Micro seconds (64bit) */
+ LIBBPF_NLA_NESTED, /**< Nested attributes */
+ __LIBBPF_NLA_TYPE_MAX,
+};
+
+#define LIBBPF_NLA_TYPE_MAX (__LIBBPF_NLA_TYPE_MAX - 1)
+
+/**
+ * @ingroup attr
+ * Attribute validation policy.
+ *
+ * See section @core_doc{core_attr_parse,Attribute Parsing} for more details.
+ */
+struct libbpf_nla_policy {
+ /** Type of attribute or LIBBPF_NLA_UNSPEC */
+ uint16_t type;
+
+ /** Minimal length of payload required */
+ uint16_t minlen;
+
+ /** Maximal length of payload allowed */
+ uint16_t maxlen;
+};
+
+/**
+ * @ingroup attr
+ * Iterate over a stream of attributes
+ * @arg pos loop counter, set to current attribute
+ * @arg head head of attribute stream
+ * @arg len length of attribute stream
+ * @arg rem initialized to len, holds bytes currently remaining in stream
+ */
+#define libbpf_nla_for_each_attr(pos, head, len, rem) \
+ for (pos = head, rem = len; \
+ nla_ok(pos, rem); \
+ pos = nla_next(pos, &(rem)))
+
+/**
+ * libbpf_nla_data - head of payload
+ * @nla: netlink attribute
+ */
+static inline void *libbpf_nla_data(const struct nlattr *nla)
+{
+ return (char *) nla + NLA_HDRLEN;
+}
+
+static inline uint8_t libbpf_nla_getattr_u8(const struct nlattr *nla)
+{
+ return *(uint8_t *)libbpf_nla_data(nla);
+}
+
+static inline uint32_t libbpf_nla_getattr_u32(const struct nlattr *nla)
+{
+ return *(uint32_t *)libbpf_nla_data(nla);
+}
+
+static inline const char *libbpf_nla_getattr_str(const struct nlattr *nla)
+{
+ return (const char *)libbpf_nla_data(nla);
+}
+
+/**
+ * libbpf_nla_len - length of payload
+ * @nla: netlink attribute
+ */
+static inline int libbpf_nla_len(const struct nlattr *nla)
+{
+ return nla->nla_len - NLA_HDRLEN;
+}
+
+int libbpf_nla_parse(struct nlattr *tb[], int maxtype, struct nlattr *head,
+ int len, struct libbpf_nla_policy *policy);
+int libbpf_nla_parse_nested(struct nlattr *tb[], int maxtype,
+ struct nlattr *nla,
+ struct libbpf_nla_policy *policy);
+
+int libbpf_nla_dump_errormsg(struct nlmsghdr *nlh);
+
+#endif /* __LIBBPF_NLATTR_H */