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Diffstat (limited to 'netlink/attr.h')
| -rw-r--r-- | netlink/attr.h | 283 |
1 files changed, 283 insertions, 0 deletions
diff --git a/netlink/attr.h b/netlink/attr.h new file mode 100644 index 0000000..8479c23 --- /dev/null +++ b/netlink/attr.h @@ -0,0 +1,283 @@ +/* + * netlink/attr.h Netlink Attributes + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation version 2.1 + * of the License. + * + * Copyright (c) 2003-2008 Thomas Graf <tgraf@suug.ch> + */ + +#ifndef NETLINK_ATTR_H_ +#define NETLINK_ATTR_H_ + +#include <netlink/netlink.h> +#include <netlink/object.h> +#include <netlink/addr.h> +#include <netlink/data.h> + +#ifdef __cplusplus +extern "C" { +#endif + +struct nl_msg; + +/** + * @name Basic Attribute Data Types + * @{ + */ + + /** + * @ingroup attr + * Basic attribute data types + * + * See \ref attr_datatypes for more details. + */ +enum { + NLA_UNSPEC, /**< Unspecified type, binary data chunk */ + NLA_U8, /**< 8 bit integer */ + NLA_U16, /**< 16 bit integer */ + NLA_U32, /**< 32 bit integer */ + NLA_U64, /**< 64 bit integer */ + NLA_STRING, /**< NUL terminated character string */ + NLA_FLAG, /**< Flag */ + NLA_MSECS, /**< Micro seconds (64bit) */ + NLA_NESTED, /**< Nested attributes */ + __NLA_TYPE_MAX, +}; + +#define NLA_TYPE_MAX (__NLA_TYPE_MAX - 1) + +/** @} */ + +/** + * @ingroup attr + * Attribute validation policy. + * + * See \ref attr_datatypes for more details. + */ +struct nla_policy { + /** Type of attribute or NLA_UNSPEC */ + uint16_t type; + + /** Minimal length of payload required */ + uint16_t minlen; + + /** Maximal length of payload allowed */ + uint16_t maxlen; +}; + +/* Size calculations */ +extern int nla_attr_size(int payload); +extern int nla_total_size(int payload); +extern int nla_padlen(int payload); + +/* Attribute parsing */ +extern int nla_type(const struct nlattr *); +extern void * nla_data(const struct nlattr *); +extern int nla_len(const struct nlattr *); +extern int nla_ok(const struct nlattr *, int); +extern struct nlattr * nla_next(const struct nlattr *, int *); +extern int nla_parse(struct nlattr **, int, struct nlattr *, + int, struct nla_policy *); +extern int nla_validate(struct nlattr *, int, int, + struct nla_policy *); +extern struct nlattr * nla_find(struct nlattr *, int, int); + +/* Helper Functions */ +extern int nla_memcpy(void *, struct nlattr *, int); +extern size_t nla_strlcpy(char *, const struct nlattr *, size_t); +extern int nla_memcmp(const struct nlattr *, const void *, size_t); +extern int nla_strcmp(const struct nlattr *, const char *); + +/* Unspecific attribute */ +extern struct nlattr * nla_reserve(struct nl_msg *, int, int); +extern int nla_put(struct nl_msg *, int, int, const void *); +extern int nla_put_data(struct nl_msg *, int, struct nl_data *); +extern int nla_put_addr(struct nl_msg *, int, struct nl_addr *); + +/* Integer attribute */ +extern uint8_t nla_get_u8(struct nlattr *); +extern int nla_put_u8(struct nl_msg *, int, uint8_t); +extern uint16_t nla_get_u16(struct nlattr *); +extern int nla_put_u16(struct nl_msg *, int, uint16_t); +extern uint32_t nla_get_u32(struct nlattr *); +extern int nla_put_u32(struct nl_msg *, int, uint32_t); +extern uint64_t nla_get_u64(struct nlattr *); +extern int nla_put_u64(struct nl_msg *, int, uint64_t); + +/* String attribute */ +extern char * nla_get_string(struct nlattr *); +extern char * nla_strdup(struct nlattr *); +extern int nla_put_string(struct nl_msg *, int, const char *); + +/* Flag attribute */ +extern int nla_get_flag(struct nlattr *); +extern int nla_put_flag(struct nl_msg *, int); + +/* Msec attribute */ +extern unsigned long nla_get_msecs(struct nlattr *); +extern int nla_put_msecs(struct nl_msg *, int, unsigned long); + +/* Attribute nesting */ +extern int nla_put_nested(struct nl_msg *, int, struct nl_msg *); +extern struct nlattr * nla_nest_start(struct nl_msg *, int); +extern int nla_nest_end(struct nl_msg *, struct nlattr *); +extern int nla_parse_nested(struct nlattr **, int, struct nlattr *, + struct nla_policy *); + +/** + * @name Attribute Construction (Exception Based) + * @{ + */ + +/** + * @ingroup attr + * Add unspecific attribute to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + * @arg attrlen Length of attribute payload. + * @arg data Head of attribute payload. + */ +#define NLA_PUT(msg, attrtype, attrlen, data) \ + do { \ + if (nla_put(msg, attrtype, attrlen, data) < 0) \ + goto nla_put_failure; \ + } while(0) + +/** + * @ingroup attr + * Add atomic type attribute to netlink message. + * @arg msg Netlink message. + * @arg type Atomic type. + * @arg attrtype Attribute type. + * @arg value Head of attribute payload. + */ +#define NLA_PUT_TYPE(msg, type, attrtype, value) \ + do { \ + type __tmp = value; \ + NLA_PUT(msg, attrtype, sizeof(type), &__tmp); \ + } while(0) + +/** + * Add 8 bit integer attribute to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + * @arg value Numeric value. + */ +#define NLA_PUT_U8(msg, attrtype, value) \ + NLA_PUT_TYPE(msg, uint8_t, attrtype, value) + +/** + * Add 16 bit integer attribute to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + * @arg value Numeric value. + */ +#define NLA_PUT_U16(msg, attrtype, value) \ + NLA_PUT_TYPE(msg, uint16_t, attrtype, value) + +/** + * Add 32 bit integer attribute to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + * @arg value Numeric value. + */ +#define NLA_PUT_U32(msg, attrtype, value) \ + NLA_PUT_TYPE(msg, uint32_t, attrtype, value) + +/** + * Add 64 bit integer attribute to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + * @arg value Numeric value. + */ +#define NLA_PUT_U64(msg, attrtype, value) \ + NLA_PUT_TYPE(msg, uint64_t, attrtype, value) + +/** + * Add string attribute to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + * @arg value NUL terminated character string. + */ +#define NLA_PUT_STRING(msg, attrtype, value) \ + NLA_PUT(msg, attrtype, strlen(value) + 1, value) + +/** + * Add flag attribute to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + */ +#define NLA_PUT_FLAG(msg, attrtype) \ + NLA_PUT(msg, attrtype, 0, NULL) + +/** + * Add msecs attribute to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + * @arg msecs Numeric value in micro seconds. + */ +#define NLA_PUT_MSECS(msg, attrtype, msecs) \ + NLA_PUT_U64(msg, attrtype, msecs) + +/** + * Add address attribute to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + * @arg addr Abstract address object. + */ +#define NLA_PUT_ADDR(msg, attrtype, addr) \ + NLA_PUT(msg, attrtype, nl_addr_get_len(addr), \ + nl_addr_get_binary_addr(addr)) + +/** + * Add abstract data attribute to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + * @arg data Abstract data object. + */ +#define NLA_PUT_DATA(msg, attrtype, data) \ + NLA_PUT(msg, attrtype, nl_data_get_size(data), \ + nl_data_get(data)) + +/** @} */ + +/** + * @name Iterators + * @{ + */ + +/** + * @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 nla_for_each_attr(pos, head, len, rem) \ + for (pos = head, rem = len; \ + nla_ok(pos, rem); \ + pos = nla_next(pos, &(rem))) + +/** + * @ingroup attr + * Iterate over a stream of nested attributes + * @arg pos loop counter, set to current attribute + * @arg nla attribute containing the nested attributes + * @arg rem initialized to len, holds bytes currently remaining in stream + */ +#define nla_for_each_nested(pos, nla, rem) \ + for (pos = nla_data(nla), rem = nla_len(nla); \ + nla_ok(pos, rem); \ + pos = nla_next(pos, &(rem))) + +/** @} */ + +#ifdef __cplusplus +} +#endif + +#endif |