1 #ifndef GENL_MAGIC_STRUCT_H 2 #define GENL_MAGIC_STRUCT_H 3 4 #ifndef GENL_MAGIC_FAMILY 5 # error "you need to define GENL_MAGIC_FAMILY before inclusion" 6 #endif 7 8 #ifndef GENL_MAGIC_VERSION 9 # error "you need to define GENL_MAGIC_VERSION before inclusion" 10 #endif 11 12 #ifndef GENL_MAGIC_INCLUDE_FILE 13 # error "you need to define GENL_MAGIC_INCLUDE_FILE before inclusion" 14 #endif 15 16 #include <linux/genetlink.h> 17 #include <linux/types.h> 18 19 #define CONCAT__(a,b) a ## b 20 #define CONCAT_(a,b) CONCAT__(a,b) 21 22 extern int CONCAT_(GENL_MAGIC_FAMILY, _genl_register)(void); 23 extern void CONCAT_(GENL_MAGIC_FAMILY, _genl_unregister)(void); 24 25 /* 26 * Extension of genl attribute validation policies {{{2 27 */ 28 29 /** 30 * GENLA_F_FLAGS - policy type flags to ease compatible ABI evolvement 31 * 32 * @GENLA_F_REQUIRED: attribute has to be present, or message is considered invalid. 33 * Adding new REQUIRED attributes breaks ABI compatibility, so don't do that. 34 * 35 * @GENLA_F_MANDATORY: if present, receiver _must_ understand it. 36 * Without this, unknown attributes (> maxtype) are _silently_ ignored 37 * by validate_nla(). 38 * 39 * To be used for API extensions, so older kernel can reject requests for not 40 * yet implemented features, if newer userland tries to use them even though 41 * the genl_family version clearly indicates they are not available. 42 * 43 * @GENLA_F_MAY_IGNORE: To clearly document the fact, for good measure. 44 * To be used for API extensions for things that have sane defaults, 45 * so newer userland can still talk to older kernel, knowing it will 46 * silently ignore these attributes if not yet known. 47 * 48 * NOTE: These flags overload 49 * NLA_F_NESTED (1 << 15) 50 * NLA_F_NET_BYTEORDER (1 << 14) 51 * from linux/netlink.h, which are not useful for validate_nla(): 52 * NET_BYTEORDER is not used anywhere, and NESTED would be specified by setting 53 * .type = NLA_NESTED in the appropriate policy. 54 * 55 * See also: nla_type() 56 */ 57 enum { 58 GENLA_F_MAY_IGNORE = 0, 59 GENLA_F_MANDATORY = 1 << 14, 60 GENLA_F_REQUIRED = 1 << 15, 61 62 /* Below will not be present in the __u16 .nla_type, but can be 63 * triggered on in <struct>_to_skb resp. <struct>_from_attrs */ 64 65 /* To exclude "sensitive" information from broadcasts, or on 66 * unpriviledged get requests. This is useful because genetlink 67 * multicast groups can be listened in on by anyone. */ 68 GENLA_F_SENSITIVE = 1 << 16, 69 70 /* INVARIAN options cannot be changed at runtime. 71 * Useful to share an attribute policy and struct definition, 72 * between some "create" and "change" commands, 73 * but disallow certain fields to be changed online. 74 */ 75 GENLA_F_INVARIANT = 1 << 17, 76 }; 77 78 #define __nla_type(x) ((__u16)((__u16)(x) & (__u16)NLA_TYPE_MASK)) 79 80 /* }}}1 81 * MAGIC 82 * multi-include macro expansion magic starts here 83 */ 84 85 /* MAGIC helpers {{{2 */ 86 87 /* possible field types */ 88 #define __flg_field(attr_nr, attr_flag, name) \ 89 __field(attr_nr, attr_flag, name, NLA_FLAG, char, \ 90 nla_get_flag, __nla_put_flag) 91 #define __u8_field(attr_nr, attr_flag, name) \ 92 __field(attr_nr, attr_flag, name, NLA_U8, unsigned char, \ 93 nla_get_u8, NLA_PUT_U8) 94 #define __u16_field(attr_nr, attr_flag, name) \ 95 __field(attr_nr, attr_flag, name, NLA_U16, __u16, \ 96 nla_get_u16, NLA_PUT_U16) 97 #define __u32_field(attr_nr, attr_flag, name) \ 98 __field(attr_nr, attr_flag, name, NLA_U32, __u32, \ 99 nla_get_u32, NLA_PUT_U32) 100 #define __u64_field(attr_nr, attr_flag, name) \ 101 __field(attr_nr, attr_flag, name, NLA_U64, __u64, \ 102 nla_get_u64, NLA_PUT_U64) 103 #define __str_field(attr_nr, attr_flag, name, maxlen) \ 104 __array(attr_nr, attr_flag, name, NLA_NUL_STRING, char, maxlen, \ 105 nla_strlcpy, NLA_PUT) 106 #define __bin_field(attr_nr, attr_flag, name, maxlen) \ 107 __array(attr_nr, attr_flag, name, NLA_BINARY, char, maxlen, \ 108 nla_memcpy, NLA_PUT) 109 110 #define __nla_put_flag(skb, attrtype, value) \ 111 do { \ 112 if (value) \ 113 NLA_PUT_FLAG(skb, attrtype); \ 114 } while (0) 115 116 #define GENL_op_init(args...) args 117 #define GENL_doit(handler) \ 118 .doit = handler, \ 119 .flags = GENL_ADMIN_PERM, 120 #define GENL_dumpit(handler) \ 121 .dumpit = handler, \ 122 .flags = GENL_ADMIN_PERM, 123 124 /* }}}1 125 * Magic: define the enum symbols for genl_ops 126 * Magic: define the enum symbols for top level attributes 127 * Magic: define the enum symbols for nested attributes 128 * {{{2 129 */ 130 131 #undef GENL_struct 132 #define GENL_struct(tag_name, tag_number, s_name, s_fields) 133 134 #undef GENL_mc_group 135 #define GENL_mc_group(group) 136 137 #undef GENL_notification 138 #define GENL_notification(op_name, op_num, mcast_group, tla_list) \ 139 op_name = op_num, 140 141 #undef GENL_op 142 #define GENL_op(op_name, op_num, handler, tla_list) \ 143 op_name = op_num, 144 145 enum { 146 #include GENL_MAGIC_INCLUDE_FILE 147 }; 148 149 #undef GENL_notification 150 #define GENL_notification(op_name, op_num, mcast_group, tla_list) 151 152 #undef GENL_op 153 #define GENL_op(op_name, op_num, handler, attr_list) 154 155 #undef GENL_struct 156 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ 157 tag_name = tag_number, 158 159 enum { 160 #include GENL_MAGIC_INCLUDE_FILE 161 }; 162 163 #undef GENL_struct 164 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ 165 enum { \ 166 s_fields \ 167 }; 168 169 #undef __field 170 #define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put) \ 171 T_ ## name = (__u16)(attr_nr | attr_flag), 172 173 #undef __array 174 #define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, __get, __put) \ 175 T_ ## name = (__u16)(attr_nr | attr_flag), 176 177 #include GENL_MAGIC_INCLUDE_FILE 178 179 /* }}}1 180 * Magic: compile time assert unique numbers for operations 181 * Magic: -"- unique numbers for top level attributes 182 * Magic: -"- unique numbers for nested attributes 183 * {{{2 184 */ 185 186 #undef GENL_struct 187 #define GENL_struct(tag_name, tag_number, s_name, s_fields) 188 189 #undef GENL_op 190 #define GENL_op(op_name, op_num, handler, attr_list) \ 191 case op_name: 192 193 #undef GENL_notification 194 #define GENL_notification(op_name, op_num, mcast_group, tla_list) \ 195 case op_name: 196 197 static inline void ct_assert_unique_operations(void) 198 { 199 switch (0) { 200 #include GENL_MAGIC_INCLUDE_FILE 201 ; 202 } 203 } 204 205 #undef GENL_op 206 #define GENL_op(op_name, op_num, handler, attr_list) 207 208 #undef GENL_notification 209 #define GENL_notification(op_name, op_num, mcast_group, tla_list) 210 211 #undef GENL_struct 212 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ 213 case tag_number: 214 215 static inline void ct_assert_unique_top_level_attributes(void) 216 { 217 switch (0) { 218 #include GENL_MAGIC_INCLUDE_FILE 219 ; 220 } 221 } 222 223 #undef GENL_struct 224 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ 225 static inline void ct_assert_unique_ ## s_name ## _attributes(void) \ 226 { \ 227 switch (0) { \ 228 s_fields \ 229 ; \ 230 } \ 231 } 232 233 #undef __field 234 #define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put) \ 235 case attr_nr: 236 237 #undef __array 238 #define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, __get, __put) \ 239 case attr_nr: 240 241 #include GENL_MAGIC_INCLUDE_FILE 242 243 /* }}}1 244 * Magic: declare structs 245 * struct <name> { 246 * fields 247 * }; 248 * {{{2 249 */ 250 251 #undef GENL_struct 252 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ 253 struct s_name { s_fields }; 254 255 #undef __field 256 #define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put) \ 257 type name; 258 259 #undef __array 260 #define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, __get, __put) \ 261 type name[maxlen]; \ 262 __u32 name ## _len; 263 264 #include GENL_MAGIC_INCLUDE_FILE 265 266 /* }}}1 */ 267 #endif /* GENL_MAGIC_STRUCT_H */ 268 /* vim: set foldmethod=marker nofoldenable : */ 269