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_U8, char, \ 90 nla_get_u8, NLA_PUT_U8) 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 __s32_field(attr_nr, attr_flag, name) \ 101 __field(attr_nr, attr_flag, name, NLA_U32, __s32, \ 102 nla_get_u32, NLA_PUT_U32) 103 #define __u64_field(attr_nr, attr_flag, name) \ 104 __field(attr_nr, attr_flag, name, NLA_U64, __u64, \ 105 nla_get_u64, NLA_PUT_U64) 106 #define __str_field(attr_nr, attr_flag, name, maxlen) \ 107 __array(attr_nr, attr_flag, name, NLA_NUL_STRING, char, maxlen, \ 108 nla_strlcpy, NLA_PUT) 109 #define __bin_field(attr_nr, attr_flag, name, maxlen) \ 110 __array(attr_nr, attr_flag, name, NLA_BINARY, char, maxlen, \ 111 nla_memcpy, NLA_PUT) 112 113 /* fields with default values */ 114 #define __flg_field_def(attr_nr, attr_flag, name, default) \ 115 __flg_field(attr_nr, attr_flag, name) 116 #define __u32_field_def(attr_nr, attr_flag, name, default) \ 117 __u32_field(attr_nr, attr_flag, name) 118 #define __s32_field_def(attr_nr, attr_flag, name, default) \ 119 __s32_field(attr_nr, attr_flag, name) 120 #define __str_field_def(attr_nr, attr_flag, name, maxlen) \ 121 __str_field(attr_nr, attr_flag, name, maxlen) 122 123 #define GENL_op_init(args...) args 124 #define GENL_doit(handler) \ 125 .doit = handler, \ 126 .flags = GENL_ADMIN_PERM, 127 #define GENL_dumpit(handler) \ 128 .dumpit = handler, \ 129 .flags = GENL_ADMIN_PERM, 130 131 /* }}}1 132 * Magic: define the enum symbols for genl_ops 133 * Magic: define the enum symbols for top level attributes 134 * Magic: define the enum symbols for nested attributes 135 * {{{2 136 */ 137 138 #undef GENL_struct 139 #define GENL_struct(tag_name, tag_number, s_name, s_fields) 140 141 #undef GENL_mc_group 142 #define GENL_mc_group(group) 143 144 #undef GENL_notification 145 #define GENL_notification(op_name, op_num, mcast_group, tla_list) \ 146 op_name = op_num, 147 148 #undef GENL_op 149 #define GENL_op(op_name, op_num, handler, tla_list) \ 150 op_name = op_num, 151 152 enum { 153 #include GENL_MAGIC_INCLUDE_FILE 154 }; 155 156 #undef GENL_notification 157 #define GENL_notification(op_name, op_num, mcast_group, tla_list) 158 159 #undef GENL_op 160 #define GENL_op(op_name, op_num, handler, attr_list) 161 162 #undef GENL_struct 163 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ 164 tag_name = tag_number, 165 166 enum { 167 #include GENL_MAGIC_INCLUDE_FILE 168 }; 169 170 #undef GENL_struct 171 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ 172 enum { \ 173 s_fields \ 174 }; 175 176 #undef __field 177 #define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put) \ 178 T_ ## name = (__u16)(attr_nr | attr_flag), 179 180 #undef __array 181 #define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, __get, __put) \ 182 T_ ## name = (__u16)(attr_nr | attr_flag), 183 184 #include GENL_MAGIC_INCLUDE_FILE 185 186 /* }}}1 187 * Magic: compile time assert unique numbers for operations 188 * Magic: -"- unique numbers for top level attributes 189 * Magic: -"- unique numbers for nested attributes 190 * {{{2 191 */ 192 193 #undef GENL_struct 194 #define GENL_struct(tag_name, tag_number, s_name, s_fields) 195 196 #undef GENL_op 197 #define GENL_op(op_name, op_num, handler, attr_list) \ 198 case op_name: 199 200 #undef GENL_notification 201 #define GENL_notification(op_name, op_num, mcast_group, tla_list) \ 202 case op_name: 203 204 static inline void ct_assert_unique_operations(void) 205 { 206 switch (0) { 207 #include GENL_MAGIC_INCLUDE_FILE 208 ; 209 } 210 } 211 212 #undef GENL_op 213 #define GENL_op(op_name, op_num, handler, attr_list) 214 215 #undef GENL_notification 216 #define GENL_notification(op_name, op_num, mcast_group, tla_list) 217 218 #undef GENL_struct 219 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ 220 case tag_number: 221 222 static inline void ct_assert_unique_top_level_attributes(void) 223 { 224 switch (0) { 225 #include GENL_MAGIC_INCLUDE_FILE 226 ; 227 } 228 } 229 230 #undef GENL_struct 231 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ 232 static inline void ct_assert_unique_ ## s_name ## _attributes(void) \ 233 { \ 234 switch (0) { \ 235 s_fields \ 236 ; \ 237 } \ 238 } 239 240 #undef __field 241 #define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put) \ 242 case attr_nr: 243 244 #undef __array 245 #define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, __get, __put) \ 246 case attr_nr: 247 248 #include GENL_MAGIC_INCLUDE_FILE 249 250 /* }}}1 251 * Magic: declare structs 252 * struct <name> { 253 * fields 254 * }; 255 * {{{2 256 */ 257 258 #undef GENL_struct 259 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ 260 struct s_name { s_fields }; 261 262 #undef __field 263 #define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put) \ 264 type name; 265 266 #undef __array 267 #define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, __get, __put) \ 268 type name[maxlen]; \ 269 __u32 name ## _len; 270 271 #include GENL_MAGIC_INCLUDE_FILE 272 273 /* }}}1 */ 274 #endif /* GENL_MAGIC_STRUCT_H */ 275 /* vim: set foldmethod=marker nofoldenable : */ 276