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Diffstat (limited to 'package/libnl-tiny/src/include/netlink/attr.h')
-rw-r--r-- | package/libnl-tiny/src/include/netlink/attr.h | 726 |
1 files changed, 726 insertions, 0 deletions
diff --git a/package/libnl-tiny/src/include/netlink/attr.h b/package/libnl-tiny/src/include/netlink/attr.h new file mode 100644 index 0000000..7076d67 --- /dev/null +++ b/package/libnl-tiny/src/include/netlink/attr.h @@ -0,0 +1,726 @@ +/* + * 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> +#include <netlink/msg.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; +}; + +/* Attribute parsing */ +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); + +/* Unspecific attribute */ +extern struct nlattr * nla_reserve(struct nl_msg *, int, int); +extern int nla_put(struct nl_msg *, int, int, const void *); + +/** + * nlmsg_find_attr - find a specific attribute in a netlink message + * @arg nlh netlink message header + * @arg hdrlen length of familiy specific header + * @arg attrtype type of attribute to look for + * + * Returns the first attribute which matches the specified type. + */ +static inline struct nlattr *nlmsg_find_attr(struct nlmsghdr *nlh, int hdrlen, int attrtype) +{ + return nla_find(nlmsg_attrdata(nlh, hdrlen), + nlmsg_attrlen(nlh, hdrlen), attrtype); +} + + +/** + * Return size of attribute whithout padding. + * @arg payload Payload length of attribute. + * + * @code + * <-------- nla_attr_size(payload) ---------> + * +------------------+- - -+- - - - - - - - - +- - -+ + * | Attribute Header | Pad | Payload | Pad | + * +------------------+- - -+- - - - - - - - - +- - -+ + * @endcode + * + * @return Size of attribute in bytes without padding. + */ +static inline int nla_attr_size(int payload) +{ + return NLA_HDRLEN + payload; +} + +/** + * Return size of attribute including padding. + * @arg payload Payload length of attribute. + * + * @code + * <----------- nla_total_size(payload) -----------> + * +------------------+- - -+- - - - - - - - - +- - -+ + * | Attribute Header | Pad | Payload | Pad | + * +------------------+- - -+- - - - - - - - - +- - -+ + * @endcode + * + * @return Size of attribute in bytes. + */ +static inline int nla_total_size(int payload) +{ + return NLA_ALIGN(nla_attr_size(payload)); +} + +/** + * Return length of padding at the tail of the attribute. + * @arg payload Payload length of attribute. + * + * @code + * +------------------+- - -+- - - - - - - - - +- - -+ + * | Attribute Header | Pad | Payload | Pad | + * +------------------+- - -+- - - - - - - - - +- - -+ + * <---> + * @endcode + * + * @return Length of padding in bytes. + */ +static inline int nla_padlen(int payload) +{ + return nla_total_size(payload) - nla_attr_size(payload); +} + +/** + * Return type of the attribute. + * @arg nla Attribute. + * + * @return Type of attribute. + */ +static inline int nla_type(const struct nlattr *nla) +{ + return nla->nla_type & NLA_TYPE_MASK; +} + +/** + * Return pointer to the payload section. + * @arg nla Attribute. + * + * @return Pointer to start of payload section. + */ +static inline void *nla_data(const struct nlattr *nla) +{ + return (char *) nla + NLA_HDRLEN; +} + +/** + * Return length of the payload . + * @arg nla Attribute + * + * @return Length of payload in bytes. + */ +static inline int nla_len(const struct nlattr *nla) +{ + return nla->nla_len - NLA_HDRLEN; +} + +/** + * Copy attribute payload to another memory area. + * @arg dest Pointer to destination memory area. + * @arg src Attribute + * @arg count Number of bytes to copy at most. + * + * Note: The number of bytes copied is limited by the length of + * the attribute payload. + * + * @return The number of bytes copied to dest. + */ +static inline int nla_memcpy(void *dest, struct nlattr *src, int count) +{ + int minlen; + + if (!src) + return 0; + + minlen = min_t(int, count, nla_len(src)); + memcpy(dest, nla_data(src), minlen); + + return minlen; +} + + +/** + * Add abstract data as unspecific attribute to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + * @arg data Abstract data object. + * + * Equivalent to nla_put() except that the length of the payload is + * derived from the abstract data object. + * + * @see nla_put + * @return 0 on success or a negative error code. + */ +static inline int nla_put_data(struct nl_msg *msg, int attrtype, struct nl_data *data) +{ + return nla_put(msg, attrtype, nl_data_get_size(data), + nl_data_get(data)); +} + +/** + * Add abstract address as unspecific attribute to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + * @arg addr Abstract address object. + * + * @see nla_put + * @return 0 on success or a negative error code. + */ +static inline int nla_put_addr(struct nl_msg *msg, int attrtype, struct nl_addr *addr) +{ + return nla_put(msg, attrtype, nl_addr_get_len(addr), + nl_addr_get_binary_addr(addr)); +} + +/** @} */ + +/** + * @name Integer Attributes + */ + +/** + * Add 8 bit integer attribute to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + * @arg value Numeric value to store as payload. + * + * @see nla_put + * @return 0 on success or a negative error code. + */ +static inline int nla_put_u8(struct nl_msg *msg, int attrtype, uint8_t value) +{ + return nla_put(msg, attrtype, sizeof(uint8_t), &value); +} + +/** + * Return value of 8 bit integer attribute. + * @arg nla 8 bit integer attribute + * + * @return Payload as 8 bit integer. + */ +static inline uint8_t nla_get_u8(struct nlattr *nla) +{ + return *(uint8_t *) nla_data(nla); +} + +/** + * Add 16 bit integer attribute to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + * @arg value Numeric value to store as payload. + * + * @see nla_put + * @return 0 on success or a negative error code. + */ +static inline int nla_put_u16(struct nl_msg *msg, int attrtype, uint16_t value) +{ + return nla_put(msg, attrtype, sizeof(uint16_t), &value); +} + +/** + * Return payload of 16 bit integer attribute. + * @arg nla 16 bit integer attribute + * + * @return Payload as 16 bit integer. + */ +static inline uint16_t nla_get_u16(struct nlattr *nla) +{ + return *(uint16_t *) nla_data(nla); +} + +/** + * Add 32 bit integer attribute to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + * @arg value Numeric value to store as payload. + * + * @see nla_put + * @return 0 on success or a negative error code. + */ +static inline int nla_put_u32(struct nl_msg *msg, int attrtype, uint32_t value) +{ + return nla_put(msg, attrtype, sizeof(uint32_t), &value); +} + +/** + * Return payload of 32 bit integer attribute. + * @arg nla 32 bit integer attribute. + * + * @return Payload as 32 bit integer. + */ +static inline uint32_t nla_get_u32(struct nlattr *nla) +{ + return *(uint32_t *) nla_data(nla); +} + +/** + * Add 64 bit integer attribute to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + * @arg value Numeric value to store as payload. + * + * @see nla_put + * @return 0 on success or a negative error code. + */ +static inline int nla_put_u64(struct nl_msg *msg, int attrtype, uint64_t value) +{ + return nla_put(msg, attrtype, sizeof(uint64_t), &value); +} + +/** + * Return payload of u64 attribute + * @arg nla u64 netlink attribute + * + * @return Payload as 64 bit integer. + */ +static inline uint64_t nla_get_u64(struct nlattr *nla) +{ + uint64_t tmp; + + nla_memcpy(&tmp, nla, sizeof(tmp)); + + return tmp; +} + +/** + * Add string attribute to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + * @arg str NUL terminated string. + * + * @see nla_put + * @return 0 on success or a negative error code. + */ +static inline int nla_put_string(struct nl_msg *msg, int attrtype, const char *str) +{ + return nla_put(msg, attrtype, strlen(str) + 1, str); +} + +/** + * Return payload of string attribute. + * @arg nla String attribute. + * + * @return Pointer to attribute payload. + */ +static inline char *nla_get_string(struct nlattr *nla) +{ + return (char *) nla_data(nla); +} + +static inline char *nla_strdup(struct nlattr *nla) +{ + return strdup(nla_get_string(nla)); +} + +/** @} */ + +/** + * @name Flag Attribute + */ + +/** + * Add flag netlink attribute to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + * + * @see nla_put + * @return 0 on success or a negative error code. + */ +static inline int nla_put_flag(struct nl_msg *msg, int attrtype) +{ + return nla_put(msg, attrtype, 0, NULL); +} + +/** + * Return true if flag attribute is set. + * @arg nla Flag netlink attribute. + * + * @return True if flag is set, otherwise false. + */ +static inline int nla_get_flag(struct nlattr *nla) +{ + return !!nla; +} + +/** @} */ + +/** + * @name Microseconds Attribute + */ + +/** + * Add a msecs netlink attribute to a netlink message + * @arg n netlink message + * @arg attrtype attribute type + * @arg msecs number of msecs + */ +static inline int nla_put_msecs(struct nl_msg *n, int attrtype, unsigned long msecs) +{ + return nla_put_u64(n, attrtype, msecs); +} + +/** + * Return payload of msecs attribute + * @arg nla msecs netlink attribute + * + * @return the number of milliseconds. + */ +static inline unsigned long nla_get_msecs(struct nlattr *nla) +{ + return nla_get_u64(nla); +} + +/** + * Add nested attributes to netlink message. + * @arg msg Netlink message. + * @arg attrtype Attribute type. + * @arg nested Message containing attributes to be nested. + * + * Takes the attributes found in the \a nested message and appends them + * to the message \a msg nested in a container of the type \a attrtype. + * The \a nested message may not have a family specific header. + * + * @see nla_put + * @return 0 on success or a negative error code. + */ +static inline int nla_put_nested(struct nl_msg *msg, int attrtype, struct nl_msg *nested) +{ + return nla_put(msg, attrtype, nlmsg_len(nested->nm_nlh), + nlmsg_data(nested->nm_nlh)); +} + +/** + * Start a new level of nested attributes. + * @arg msg Netlink message. + * @arg attrtype Attribute type of container. + * + * @return Pointer to container attribute. + */ +static inline struct nlattr *nla_nest_start(struct nl_msg *msg, int attrtype) +{ + struct nlattr *start = (struct nlattr *) nlmsg_tail(msg->nm_nlh); + + if (nla_put(msg, attrtype, 0, NULL) < 0) + return NULL; + + return start; +} + +/** + * Finalize nesting of attributes. + * @arg msg Netlink message. + * @arg start Container attribute as returned from nla_nest_start(). + * + * Corrects the container attribute header to include the appeneded attributes. + * + * @return 0 + */ +static inline int nla_nest_end(struct nl_msg *msg, struct nlattr *start) +{ + start->nla_len = (unsigned char *) nlmsg_tail(msg->nm_nlh) - + (unsigned char *) start; + return 0; +} + +/** + * Create attribute index based on nested attribute + * @arg tb Index array to be filled (maxtype+1 elements). + * @arg maxtype Maximum attribute type expected and accepted. + * @arg nla Nested Attribute. + * @arg policy Attribute validation policy. + * + * Feeds the stream of attributes nested into the specified attribute + * to nla_parse(). + * + * @see nla_parse + * @return 0 on success or a negative error code. + */ +static inline int nla_parse_nested(struct nlattr *tb[], int maxtype, struct nlattr *nla, + struct nla_policy *policy) +{ + return nla_parse(tb, maxtype, nla_data(nla), nla_len(nla), policy); +} + +/** + * Compare attribute payload with memory area. + * @arg nla Attribute. + * @arg data Memory area to compare to. + * @arg size Number of bytes to compare. + * + * @see memcmp(3) + * @return An integer less than, equal to, or greater than zero. + */ +static inline int nla_memcmp(const struct nlattr *nla, const void *data, size_t size) +{ + int d = nla_len(nla) - size; + + if (d == 0) + d = memcmp(nla_data(nla), data, size); + + return d; +} + +/** + * Compare string attribute payload with string + * @arg nla Attribute of type NLA_STRING. + * @arg str NUL terminated string. + * + * @see strcmp(3) + * @return An integer less than, equal to, or greater than zero. + */ +static inline int nla_strcmp(const struct nlattr *nla, const char *str) +{ + int len = strlen(str) + 1; + int d = nla_len(nla) - len; + + if (d == 0) + d = memcmp(nla_data(nla), str, len); + + return d; +} + +/** + * Copy string attribute payload to a buffer. + * @arg dst Pointer to destination buffer. + * @arg nla Attribute of type NLA_STRING. + * @arg dstsize Size of destination buffer in bytes. + * + * Copies at most dstsize - 1 bytes to the destination buffer. + * The result is always a valid NUL terminated string. Unlike + * strlcpy the destination buffer is always padded out. + * + * @return The length of string attribute without the terminating NUL. + */ +static inline size_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize) +{ + size_t srclen = nla_len(nla); + char *src = nla_data(nla); + + if (srclen > 0 && src[srclen - 1] == '\0') + srclen--; + + if (dstsize > 0) { + size_t len = (srclen >= dstsize) ? dstsize - 1 : srclen; + + memset(dst, 0, dstsize); + memcpy(dst, src, len); + } + + return srclen; +} + + +/** + * @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)) + +/** @} */ + +/** + * @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 |