diff options
Diffstat (limited to 'include/net/netlink.h')
| -rw-r--r-- | include/net/netlink.h | 238 |
1 files changed, 191 insertions, 47 deletions
diff --git a/include/net/netlink.h b/include/net/netlink.h index c77ed51c18f1..ab26a5e3558b 100644 --- a/include/net/netlink.h +++ b/include/net/netlink.h @@ -369,21 +369,48 @@ struct nl_info { bool skip_notify; }; +/** + * enum netlink_validation - netlink message/attribute validation levels + * @NL_VALIDATE_LIBERAL: Old-style "be liberal" validation, not caring about + * extra data at the end of the message, attributes being longer than + * they should be, or unknown attributes being present. + * @NL_VALIDATE_TRAILING: Reject junk data encountered after attribute parsing. + * @NL_VALIDATE_MAXTYPE: Reject attributes > max type; Together with _TRAILING + * this is equivalent to the old nla_parse_strict()/nlmsg_parse_strict(). + * @NL_VALIDATE_UNSPEC: Reject attributes with NLA_UNSPEC in the policy. + * This can safely be set by the kernel when the given policy has no + * NLA_UNSPEC anymore, and can thus be used to ensure policy entries + * are enforced going forward. + * @NL_VALIDATE_STRICT_ATTRS: strict attribute policy parsing (e.g. + * U8, U16, U32 must have exact size, etc.) + */ +enum netlink_validation { + NL_VALIDATE_LIBERAL = 0, + NL_VALIDATE_TRAILING = BIT(0), + NL_VALIDATE_MAXTYPE = BIT(1), + NL_VALIDATE_UNSPEC = BIT(2), + NL_VALIDATE_STRICT_ATTRS = BIT(3), +}; + +#define NL_VALIDATE_DEPRECATED_STRICT (NL_VALIDATE_TRAILING |\ + NL_VALIDATE_MAXTYPE) +#define NL_VALIDATE_STRICT (NL_VALIDATE_TRAILING |\ + NL_VALIDATE_MAXTYPE |\ + NL_VALIDATE_UNSPEC |\ + NL_VALIDATE_STRICT_ATTRS) + int netlink_rcv_skb(struct sk_buff *skb, int (*cb)(struct sk_buff *, struct nlmsghdr *, struct netlink_ext_ack *)); int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 portid, unsigned int group, int report, gfp_t flags); -int nla_validate(const struct nlattr *head, int len, int maxtype, - const struct nla_policy *policy, - struct netlink_ext_ack *extack); -int nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head, - int len, const struct nla_policy *policy, - struct netlink_ext_ack *extack); -int nla_parse_strict(struct nlattr **tb, int maxtype, const struct nlattr *head, - int len, const struct nla_policy *policy, - struct netlink_ext_ack *extack); +int __nla_validate(const struct nlattr *head, int len, int maxtype, + const struct nla_policy *policy, unsigned int validate, + struct netlink_ext_ack *extack); +int __nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head, + int len, const struct nla_policy *policy, unsigned int validate, + struct netlink_ext_ack *extack); int nla_policy_len(const struct nla_policy *, int); struct nlattr *nla_find(const struct nlattr *head, int len, int attrtype); size_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize); @@ -512,42 +539,121 @@ nlmsg_next(const struct nlmsghdr *nlh, int *remaining) } /** - * nlmsg_parse - parse attributes of a netlink message + * nla_parse_deprecated - Parse a stream of attributes into a tb buffer + * @tb: destination array with maxtype+1 elements + * @maxtype: maximum attribute type to be expected + * @head: head of attribute stream + * @len: length of attribute stream + * @policy: validation policy + * @extack: extended ACK pointer + * + * Parses a stream of attributes and stores a pointer to each attribute in + * the tb array accessible via the attribute type. Attributes with a type + * exceeding maxtype will be ignored and attributes from the policy are not + * always strictly validated (only for new attributes). + * + * Returns 0 on success or a negative error code. + */ +static inline int nla_parse_deprecated(struct nlattr **tb, int maxtype, + const struct nlattr *head, int len, + const struct nla_policy *policy, + struct netlink_ext_ack *extack) +{ + return __nla_parse(tb, maxtype, head, len, policy, + NL_VALIDATE_LIBERAL, extack); +} + +/** + * nla_parse_deprecated_strict - Parse a stream of attributes into a tb buffer + * @tb: destination array with maxtype+1 elements + * @maxtype: maximum attribute type to be expected + * @head: head of attribute stream + * @len: length of attribute stream + * @policy: validation policy + * @extack: extended ACK pointer + * + * Parses a stream of attributes and stores a pointer to each attribute in + * the tb array accessible via the attribute type. Attributes with a type + * exceeding maxtype will be rejected as well as trailing data, but the + * policy is not completely strictly validated (only for new attributes). + * + * Returns 0 on success or a negative error code. + */ +static inline int nla_parse_deprecated_strict(struct nlattr **tb, int maxtype, + const struct nlattr *head, + int len, + const struct nla_policy *policy, + struct netlink_ext_ack *extack) +{ + return __nla_parse(tb, maxtype, head, len, policy, + NL_VALIDATE_DEPRECATED_STRICT, extack); +} + +/** + * __nlmsg_parse - parse attributes of a netlink message * @nlh: netlink message header * @hdrlen: length of family specific header * @tb: destination array with maxtype+1 elements * @maxtype: maximum attribute type to be expected * @policy: validation policy + * @validate: validation strictness * @extack: extended ACK report struct * * See nla_parse() */ -static inline int nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen, - struct nlattr *tb[], int maxtype, - const struct nla_policy *policy, - struct netlink_ext_ack *extack) +static inline int __nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen, + struct nlattr *tb[], int maxtype, + const struct nla_policy *policy, + unsigned int validate, + struct netlink_ext_ack *extack) { if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) { NL_SET_ERR_MSG(extack, "Invalid header length"); return -EINVAL; } - return nla_parse(tb, maxtype, nlmsg_attrdata(nlh, hdrlen), - nlmsg_attrlen(nlh, hdrlen), policy, extack); + return __nla_parse(tb, maxtype, nlmsg_attrdata(nlh, hdrlen), + nlmsg_attrlen(nlh, hdrlen), policy, validate, + extack); } -static inline int nlmsg_parse_strict(const struct nlmsghdr *nlh, int hdrlen, - struct nlattr *tb[], int maxtype, - const struct nla_policy *policy, - struct netlink_ext_ack *extack) +/** + * nlmsg_parse_deprecated - parse attributes of a netlink message + * @nlh: netlink message header + * @hdrlen: length of family specific header + * @tb: destination array with maxtype+1 elements + * @maxtype: maximum attribute type to be expected + * @extack: extended ACK report struct + * + * See nla_parse_deprecated() + */ +static inline int nlmsg_parse_deprecated(const struct nlmsghdr *nlh, int hdrlen, + struct nlattr *tb[], int maxtype, + const struct nla_policy *policy, + struct netlink_ext_ack *extack) { - if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) { - NL_SET_ERR_MSG(extack, "Invalid header length"); - return -EINVAL; - } + return __nlmsg_parse(nlh, hdrlen, tb, maxtype, policy, + NL_VALIDATE_LIBERAL, extack); +} - return nla_parse_strict(tb, maxtype, nlmsg_attrdata(nlh, hdrlen), - nlmsg_attrlen(nlh, hdrlen), policy, extack); +/** + * nlmsg_parse_deprecated_strict - parse attributes of a netlink message + * @nlh: netlink message header + * @hdrlen: length of family specific header + * @tb: destination array with maxtype+1 elements + * @maxtype: maximum attribute type to be expected + * @extack: extended ACK report struct + * + * See nla_parse_deprecated_strict() + */ +static inline int +nlmsg_parse_deprecated_strict(const struct nlmsghdr *nlh, int hdrlen, + struct nlattr *tb[], int maxtype, + const struct nla_policy *policy, + struct netlink_ext_ack *extack) +{ + return __nlmsg_parse(nlh, hdrlen, tb, maxtype, policy, + NL_VALIDATE_DEPRECATED_STRICT, extack); } /** @@ -566,26 +672,53 @@ static inline struct nlattr *nlmsg_find_attr(const struct nlmsghdr *nlh, } /** - * nlmsg_validate - validate a netlink message including attributes + * nla_validate_deprecated - Validate a stream of attributes + * @head: head of attribute stream + * @len: length of attribute stream + * @maxtype: maximum attribute type to be expected + * @policy: validation policy + * @validate: validation strictness + * @extack: extended ACK report struct + * + * Validates all attributes in the specified attribute stream against the + * specified policy. Validation is done in liberal mode. + * See documenation of struct nla_policy for more details. + * + * Returns 0 on success or a negative error code. + */ +static inline int nla_validate_deprecated(const struct nlattr *head, int len, + int maxtype, + const struct nla_policy *policy, + struct netlink_ext_ack *extack) +{ + return __nla_validate(head, len, maxtype, policy, NL_VALIDATE_LIBERAL, + extack); +} + + +/** + * nlmsg_validate_deprecated - validate a netlink message including attributes * @nlh: netlinket message header * @hdrlen: length of familiy specific header * @maxtype: maximum attribute type to be expected * @policy: validation policy * @extack: extended ACK report struct */ -static inline int nlmsg_validate(const struct nlmsghdr *nlh, - int hdrlen, int maxtype, - const struct nla_policy *policy, - struct netlink_ext_ack *extack) +static inline int nlmsg_validate_deprecated(const struct nlmsghdr *nlh, + int hdrlen, int maxtype, + const struct nla_policy *policy, + struct netlink_ext_ack *extack) { if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) return -EINVAL; - return nla_validate(nlmsg_attrdata(nlh, hdrlen), - nlmsg_attrlen(nlh, hdrlen), maxtype, policy, - extack); + return __nla_validate(nlmsg_attrdata(nlh, hdrlen), + nlmsg_attrlen(nlh, hdrlen), maxtype, + policy, NL_VALIDATE_LIBERAL, extack); } + + /** * nlmsg_report - need to report back to application? * @nlh: netlink message header @@ -899,22 +1032,22 @@ nla_find_nested(const struct nlattr *nla, int attrtype) } /** - * nla_parse_nested - parse nested attributes + * nla_parse_nested_deprecated - parse nested attributes * @tb: destination array with maxtype+1 elements * @maxtype: maximum attribute type to be expected * @nla: attribute containing the nested attributes * @policy: validation policy * @extack: extended ACK report struct * - * See nla_parse() + * See nla_parse_deprecated() */ -static inline int nla_parse_nested(struct nlattr *tb[], int maxtype, - const struct nlattr *nla, - const struct nla_policy *policy, - struct netlink_ext_ack *extack) +static inline int nla_parse_nested_deprecated(struct nlattr *tb[], int maxtype, + const struct nlattr *nla, + const struct nla_policy *policy, + struct netlink_ext_ack *extack) { - return nla_parse(tb, maxtype, nla_data(nla), nla_len(nla), policy, - extack); + return __nla_parse(tb, maxtype, nla_data(nla), nla_len(nla), policy, + NL_VALIDATE_LIBERAL, extack); } /** @@ -1489,6 +1622,7 @@ static inline void nla_nest_cancel(struct sk_buff *skb, struct nlattr *start) * @start: container attribute * @maxtype: maximum attribute type to be expected * @policy: validation policy + * @validate: validation strictness * @extack: extended ACK report struct * * Validates all attributes in the nested attribute stream against the @@ -1497,12 +1631,22 @@ static inline void nla_nest_cancel(struct sk_buff *skb, struct nlattr *start) * * Returns 0 on success or a negative error code. */ -static inline int nla_validate_nested(const struct nlattr *start, int maxtype, - const struct nla_policy *policy, - struct netlink_ext_ack *extack) +static inline int __nla_validate_nested(const struct nlattr *start, int maxtype, + const struct nla_policy *policy, + unsigned int validate, + struct netlink_ext_ack *extack) +{ + return __nla_validate(nla_data(start), nla_len(start), maxtype, policy, + validate, extack); +} + +static inline int +nla_validate_nested_deprecated(const struct nlattr *start, int maxtype, + const struct nla_policy *policy, + struct netlink_ext_ack *extack) { - return nla_validate(nla_data(start), nla_len(start), maxtype, policy, - extack); + return __nla_validate_nested(start, maxtype, policy, + NL_VALIDATE_LIBERAL, extack); } /** |