diff options
Diffstat (limited to 'include/net/netlink.h')
-rw-r--r-- | include/net/netlink.h | 251 |
1 files changed, 185 insertions, 66 deletions
diff --git a/include/net/netlink.h b/include/net/netlink.h index 56c365dc6dc7..6bfa972f2fbf 100644 --- a/include/net/netlink.h +++ b/include/net/netlink.h @@ -142,7 +142,7 @@ * Attribute Misc: * nla_memcpy(dest, nla, count) copy attribute into memory * nla_memcmp(nla, data, size) compare attribute with memory area - * nla_strlcpy(dst, nla, size) copy attribute to a sized string + * nla_strscpy(dst, nla, size) copy attribute to a sized string * nla_strcmp(nla, str) compare attribute with string * * Attribute Parsing: @@ -181,19 +181,29 @@ enum { NLA_S64, NLA_BITFIELD32, NLA_REJECT, - NLA_EXACT_LEN, - NLA_EXACT_LEN_WARN, - NLA_MIN_LEN, + NLA_BE16, + NLA_BE32, __NLA_TYPE_MAX, }; #define NLA_TYPE_MAX (__NLA_TYPE_MAX - 1) +struct netlink_range_validation { + u64 min, max; +}; + +struct netlink_range_validation_signed { + s64 min, max; +}; + enum nla_policy_validation { NLA_VALIDATE_NONE, NLA_VALIDATE_RANGE, + NLA_VALIDATE_RANGE_WARN_TOO_LONG, NLA_VALIDATE_MIN, NLA_VALIDATE_MAX, + NLA_VALIDATE_MASK, + NLA_VALIDATE_RANGE_PTR, NLA_VALIDATE_FUNCTION, }; @@ -213,79 +223,98 @@ enum nla_policy_validation { * NLA_NUL_STRING Maximum length of string (excluding NUL) * NLA_FLAG Unused * NLA_BINARY Maximum length of attribute payload - * NLA_MIN_LEN Minimum length of attribute payload + * (but see also below with the validation type) * NLA_NESTED, * NLA_NESTED_ARRAY Length verification is done by checking len of * nested header (or empty); len field is used if - * validation_data is also used, for the max attr + * nested_policy is also used, for the max attr * number in the nested policy. * NLA_U8, NLA_U16, * NLA_U32, NLA_U64, * NLA_S8, NLA_S16, * NLA_S32, NLA_S64, + * NLA_BE16, NLA_BE32, * NLA_MSECS Leaving the length field zero will verify the * given type fits, using it verifies minimum length * just like "All other" * NLA_BITFIELD32 Unused * NLA_REJECT Unused - * NLA_EXACT_LEN Attribute must have exactly this length, otherwise - * it is rejected. - * NLA_EXACT_LEN_WARN Attribute should have exactly this length, a warning - * is logged if it is longer, shorter is rejected. - * NLA_MIN_LEN Minimum length of attribute payload * All other Minimum length of attribute payload * - * Meaning of `validation_data' field: + * Meaning of validation union: * NLA_BITFIELD32 This is a 32-bit bitmap/bitselector attribute and - * validation data must point to a u32 value of valid - * flags - * NLA_REJECT This attribute is always rejected and validation data + * `bitfield32_valid' is the u32 value of valid flags + * NLA_REJECT This attribute is always rejected and `reject_message' * may point to a string to report as the error instead * of the generic one in extended ACK. - * NLA_NESTED Points to a nested policy to validate, must also set - * `len' to the max attribute number. + * NLA_NESTED `nested_policy' to a nested policy to validate, must + * also set `len' to the max attribute number. Use the + * provided NLA_POLICY_NESTED() macro. * Note that nla_parse() will validate, but of course not * parse, the nested sub-policies. - * NLA_NESTED_ARRAY Points to a nested policy to validate, must also set - * `len' to the max attribute number. The difference to - * NLA_NESTED is the structure - NLA_NESTED has the - * nested attributes directly inside, while an array has - * the nested attributes at another level down and the - * attributes directly in the nesting don't matter. - * All other Unused - but note that it's a union - * - * Meaning of `min' and `max' fields, use via NLA_POLICY_MIN, NLA_POLICY_MAX - * and NLA_POLICY_RANGE: + * NLA_NESTED_ARRAY `nested_policy' points to a nested policy to validate, + * must also set `len' to the max attribute number. Use + * the provided NLA_POLICY_NESTED_ARRAY() macro. + * The difference to NLA_NESTED is the structure: + * NLA_NESTED has the nested attributes directly inside + * while an array has the nested attributes at another + * level down and the attribute types directly in the + * nesting don't matter. * NLA_U8, * NLA_U16, * NLA_U32, * NLA_U64, + * NLA_BE16, + * NLA_BE32, * NLA_S8, * NLA_S16, * NLA_S32, - * NLA_S64 These are used depending on the validation_type - * field, if that is min/max/range then the minimum, - * maximum and both are used (respectively) to check + * NLA_S64 The `min' and `max' fields are used depending on the + * validation_type field, if that is min/max/range then + * the min, max or both are used (respectively) to check * the value of the integer attribute. * Note that in the interest of code simplicity and * struct size both limits are s16, so you cannot * enforce a range that doesn't fall within the range * of s16 - do that as usual in the code instead. + * Use the NLA_POLICY_MIN(), NLA_POLICY_MAX() and + * NLA_POLICY_RANGE() macros. + * NLA_U8, + * NLA_U16, + * NLA_U32, + * NLA_U64 If the validation_type field instead is set to + * NLA_VALIDATE_RANGE_PTR, `range' must be a pointer + * to a struct netlink_range_validation that indicates + * the min/max values. + * Use NLA_POLICY_FULL_RANGE(). + * NLA_S8, + * NLA_S16, + * NLA_S32, + * NLA_S64 If the validation_type field instead is set to + * NLA_VALIDATE_RANGE_PTR, `range_signed' must be a + * pointer to a struct netlink_range_validation_signed + * that indicates the min/max values. + * Use NLA_POLICY_FULL_RANGE_SIGNED(). + * + * NLA_BINARY If the validation type is like the ones for integers + * above, then the min/max length (not value like for + * integers) of the attribute is enforced. + * * All other Unused - but note that it's a union * * Meaning of `validate' field, use via NLA_POLICY_VALIDATE_FN: - * NLA_BINARY Validation function called for the attribute, - * not compatible with use of the validation_data - * as in NLA_BITFIELD32, NLA_REJECT, NLA_NESTED and - * NLA_NESTED_ARRAY. + * NLA_BINARY Validation function called for the attribute. * All other Unused - but note that it's a union * * Example: + * + * static const u32 myvalidflags = 0xff231023; + * * static const struct nla_policy my_policy[ATTR_MAX+1] = { * [ATTR_FOO] = { .type = NLA_U16 }, * [ATTR_BAR] = { .type = NLA_STRING, .len = BARSIZ }, - * [ATTR_BAZ] = { .type = NLA_EXACT_LEN, .len = sizeof(struct mystruct) }, - * [ATTR_GOO] = { .type = NLA_BITFIELD32, .validation_data = &myvalidflags }, + * [ATTR_BAZ] = NLA_POLICY_EXACT_LEN(sizeof(struct mystruct)), + * [ATTR_GOO] = NLA_POLICY_BITFIELD32(myvalidflags), * }; */ struct nla_policy { @@ -293,22 +322,20 @@ struct nla_policy { u8 validation_type; u16 len; union { - const void *validation_data; - struct { - s16 min, max; - }; - int (*validate)(const struct nlattr *attr, - struct netlink_ext_ack *extack); - /* This entry is special, and used for the attribute at index 0 + /** + * @strict_start_type: first attribute to validate strictly + * + * This entry is special, and used for the attribute at index 0 * only, and specifies special data about the policy, namely it * specifies the "boundary type" where strict length validation * starts for any attribute types >= this value, also, strict * nesting validation starts here. * * Additionally, it means that NLA_UNSPEC is actually NLA_REJECT - * for any types >= this, so need to use NLA_MIN_LEN to get the - * previous pure { .len = xyz } behaviour. The advantage of this - * is that types not specified in the policy will be rejected. + * for any types >= this, so need to use NLA_POLICY_MIN_LEN() to + * get the previous pure { .len = xyz } behaviour. The advantage + * of this is that types not specified in the policy will be + * rejected. * * For completely new families it should be set to 1 so that the * validation is enforced for all attributes. For existing ones @@ -317,57 +344,103 @@ struct nla_policy { * was added to enforce strict validation from thereon. */ u16 strict_start_type; + + /* private: use NLA_POLICY_*() to set */ + const u32 bitfield32_valid; + const u32 mask; + const char *reject_message; + const struct nla_policy *nested_policy; + struct netlink_range_validation *range; + struct netlink_range_validation_signed *range_signed; + struct { + s16 min, max; + }; + int (*validate)(const struct nlattr *attr, + struct netlink_ext_ack *extack); }; }; -#define NLA_POLICY_EXACT_LEN(_len) { .type = NLA_EXACT_LEN, .len = _len } -#define NLA_POLICY_EXACT_LEN_WARN(_len) { .type = NLA_EXACT_LEN_WARN, \ - .len = _len } -#define NLA_POLICY_MIN_LEN(_len) { .type = NLA_MIN_LEN, .len = _len } - #define NLA_POLICY_ETH_ADDR NLA_POLICY_EXACT_LEN(ETH_ALEN) #define NLA_POLICY_ETH_ADDR_COMPAT NLA_POLICY_EXACT_LEN_WARN(ETH_ALEN) #define _NLA_POLICY_NESTED(maxattr, policy) \ - { .type = NLA_NESTED, .validation_data = policy, .len = maxattr } + { .type = NLA_NESTED, .nested_policy = policy, .len = maxattr } #define _NLA_POLICY_NESTED_ARRAY(maxattr, policy) \ - { .type = NLA_NESTED_ARRAY, .validation_data = policy, .len = maxattr } + { .type = NLA_NESTED_ARRAY, .nested_policy = policy, .len = maxattr } #define NLA_POLICY_NESTED(policy) \ _NLA_POLICY_NESTED(ARRAY_SIZE(policy) - 1, policy) #define NLA_POLICY_NESTED_ARRAY(policy) \ _NLA_POLICY_NESTED_ARRAY(ARRAY_SIZE(policy) - 1, policy) +#define NLA_POLICY_BITFIELD32(valid) \ + { .type = NLA_BITFIELD32, .bitfield32_valid = valid } + +#define __NLA_IS_UINT_TYPE(tp) \ + (tp == NLA_U8 || tp == NLA_U16 || tp == NLA_U32 || tp == NLA_U64) +#define __NLA_IS_SINT_TYPE(tp) \ + (tp == NLA_S8 || tp == NLA_S16 || tp == NLA_S32 || tp == NLA_S64) +#define __NLA_IS_BEINT_TYPE(tp) \ + (tp == NLA_BE16 || tp == NLA_BE32) #define __NLA_ENSURE(condition) BUILD_BUG_ON_ZERO(!(condition)) -#define NLA_ENSURE_INT_TYPE(tp) \ - (__NLA_ENSURE(tp == NLA_S8 || tp == NLA_U8 || \ - tp == NLA_S16 || tp == NLA_U16 || \ - tp == NLA_S32 || tp == NLA_U32 || \ - tp == NLA_S64 || tp == NLA_U64) + tp) +#define NLA_ENSURE_UINT_TYPE(tp) \ + (__NLA_ENSURE(__NLA_IS_UINT_TYPE(tp)) + tp) +#define NLA_ENSURE_UINT_OR_BINARY_TYPE(tp) \ + (__NLA_ENSURE(__NLA_IS_UINT_TYPE(tp) || \ + tp == NLA_MSECS || \ + tp == NLA_BINARY) + tp) +#define NLA_ENSURE_SINT_TYPE(tp) \ + (__NLA_ENSURE(__NLA_IS_SINT_TYPE(tp)) + tp) +#define NLA_ENSURE_INT_OR_BINARY_TYPE(tp) \ + (__NLA_ENSURE(__NLA_IS_UINT_TYPE(tp) || \ + __NLA_IS_SINT_TYPE(tp) || \ + __NLA_IS_BEINT_TYPE(tp) || \ + tp == NLA_MSECS || \ + tp == NLA_BINARY) + tp) #define NLA_ENSURE_NO_VALIDATION_PTR(tp) \ (__NLA_ENSURE(tp != NLA_BITFIELD32 && \ tp != NLA_REJECT && \ tp != NLA_NESTED && \ tp != NLA_NESTED_ARRAY) + tp) +#define NLA_ENSURE_BEINT_TYPE(tp) \ + (__NLA_ENSURE(__NLA_IS_BEINT_TYPE(tp)) + tp) #define NLA_POLICY_RANGE(tp, _min, _max) { \ - .type = NLA_ENSURE_INT_TYPE(tp), \ + .type = NLA_ENSURE_INT_OR_BINARY_TYPE(tp), \ .validation_type = NLA_VALIDATE_RANGE, \ .min = _min, \ .max = _max \ } +#define NLA_POLICY_FULL_RANGE(tp, _range) { \ + .type = NLA_ENSURE_UINT_OR_BINARY_TYPE(tp), \ + .validation_type = NLA_VALIDATE_RANGE_PTR, \ + .range = _range, \ +} + +#define NLA_POLICY_FULL_RANGE_SIGNED(tp, _range) { \ + .type = NLA_ENSURE_SINT_TYPE(tp), \ + .validation_type = NLA_VALIDATE_RANGE_PTR, \ + .range_signed = _range, \ +} + #define NLA_POLICY_MIN(tp, _min) { \ - .type = NLA_ENSURE_INT_TYPE(tp), \ + .type = NLA_ENSURE_INT_OR_BINARY_TYPE(tp), \ .validation_type = NLA_VALIDATE_MIN, \ .min = _min, \ } #define NLA_POLICY_MAX(tp, _max) { \ - .type = NLA_ENSURE_INT_TYPE(tp), \ + .type = NLA_ENSURE_INT_OR_BINARY_TYPE(tp), \ .validation_type = NLA_VALIDATE_MAX, \ .max = _max, \ } +#define NLA_POLICY_MASK(tp, _mask) { \ + .type = NLA_ENSURE_UINT_TYPE(tp), \ + .validation_type = NLA_VALIDATE_MASK, \ + .mask = _mask, \ +} + #define NLA_POLICY_VALIDATE_FN(tp, fn, ...) { \ .type = NLA_ENSURE_NO_VALIDATION_PTR(tp), \ .validation_type = NLA_VALIDATE_FUNCTION, \ @@ -375,6 +448,15 @@ struct nla_policy { .len = __VA_ARGS__ + 0, \ } +#define NLA_POLICY_EXACT_LEN(_len) NLA_POLICY_RANGE(NLA_BINARY, _len, _len) +#define NLA_POLICY_EXACT_LEN_WARN(_len) { \ + .type = NLA_BINARY, \ + .validation_type = NLA_VALIDATE_RANGE_WARN_TOO_LONG, \ + .min = _len, \ + .max = _len \ +} +#define NLA_POLICY_MIN_LEN(_len) NLA_POLICY_MIN(NLA_BINARY, _len) + /** * struct nl_info - netlink source information * @nlh: Netlink message header of original request @@ -439,7 +521,7 @@ int __nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head, 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); +ssize_t nla_strscpy(char *dst, const struct nlattr *nla, size_t dstsize); char *nla_strdup(const struct nlattr *nla, gfp_t flags); int nla_memcpy(void *dest, const struct nlattr *src, int count); int nla_memcmp(const struct nlattr *nla, const void *data, size_t size); @@ -674,7 +756,7 @@ static inline int __nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen, * @hdrlen: length of family specific header * @tb: destination array with maxtype+1 elements * @maxtype: maximum attribute type to be expected - * @validate: validation strictness + * @policy: validation policy * @extack: extended ACK report struct * * See nla_parse() @@ -694,6 +776,7 @@ static inline int nlmsg_parse(const struct nlmsghdr *nlh, int hdrlen, * @hdrlen: length of family specific header * @tb: destination array with maxtype+1 elements * @maxtype: maximum attribute type to be expected + * @policy: validation policy * @extack: extended ACK report struct * * See nla_parse_deprecated() @@ -713,6 +796,7 @@ static inline int nlmsg_parse_deprecated(const struct nlmsghdr *nlh, int hdrlen, * @hdrlen: length of family specific header * @tb: destination array with maxtype+1 elements * @maxtype: maximum attribute type to be expected + * @policy: validation policy * @extack: extended ACK report struct * * See nla_parse_deprecated_strict() @@ -748,7 +832,6 @@ static inline struct nlattr *nlmsg_find_attr(const struct nlmsghdr *nlh, * @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 @@ -772,7 +855,6 @@ static inline int nla_validate_deprecated(const struct nlattr *head, int len, * @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 @@ -820,7 +902,7 @@ static inline int nlmsg_validate_deprecated(const struct nlmsghdr *nlh, */ static inline int nlmsg_report(const struct nlmsghdr *nlh) { - return !!(nlh->nlmsg_flags & NLM_F_ECHO); + return nlh ? !!(nlh->nlmsg_flags & NLM_F_ECHO) : 0; } /** @@ -1466,6 +1548,21 @@ static inline int nla_put_in6_addr(struct sk_buff *skb, int attrtype, } /** + * nla_put_bitfield32 - Add a bitfield32 netlink attribute to a socket buffer + * @skb: socket buffer to add attribute to + * @attrtype: attribute type + * @value: value carrying bits + * @selector: selector of valid bits + */ +static inline int nla_put_bitfield32(struct sk_buff *skb, int attrtype, + __u32 value, __u32 selector) +{ + struct nla_bitfield32 tmp = { value, selector, }; + + return nla_put(skb, attrtype, sizeof(tmp), &tmp); +} + +/** * nla_get_u32 - return payload of u32 attribute * @nla: u32 netlink attribute */ @@ -1861,4 +1958,26 @@ static inline bool nla_is_last(const struct nlattr *nla, int rem) return nla->nla_len == rem; } +void nla_get_range_unsigned(const struct nla_policy *pt, + struct netlink_range_validation *range); +void nla_get_range_signed(const struct nla_policy *pt, + struct netlink_range_validation_signed *range); + +struct netlink_policy_dump_state; + +int netlink_policy_dump_add_policy(struct netlink_policy_dump_state **pstate, + const struct nla_policy *policy, + unsigned int maxtype); +int netlink_policy_dump_get_policy_idx(struct netlink_policy_dump_state *state, + const struct nla_policy *policy, + unsigned int maxtype); +bool netlink_policy_dump_loop(struct netlink_policy_dump_state *state); +int netlink_policy_dump_write(struct sk_buff *skb, + struct netlink_policy_dump_state *state); +int netlink_policy_dump_attr_size_estimate(const struct nla_policy *pt); +int netlink_policy_dump_write_attr(struct sk_buff *skb, + const struct nla_policy *pt, + int nestattr); +void netlink_policy_dump_free(struct netlink_policy_dump_state *state); + #endif |