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 /* This will not be present in the __u16 .nla_type, but can be 63 * triggered on in <struct>_to_skb, to exclude "sensitive" 64 * information from broadcasts, or on unpriviledged get requests. 65 * This is useful because genetlink multicast groups can be listened in 66 * on by anyone. */ 67 GENLA_F_SENSITIVE = 1 << 16, 68 }; 69 70 #define __nla_type(x) ((__u16)((__u16)(x) & (__u16)NLA_TYPE_MASK)) 71 72 /* }}}1 73 * MAGIC 74 * multi-include macro expansion magic starts here 75 */ 76 77 /* MAGIC helpers {{{2 */ 78 79 /* possible field types */ 80 #define __flg_field(attr_nr, attr_flag, name) \ 81 __field(attr_nr, attr_flag, name, NLA_FLAG, char, \ 82 nla_get_flag, __nla_put_flag) 83 #define __u8_field(attr_nr, attr_flag, name) \ 84 __field(attr_nr, attr_flag, name, NLA_U8, unsigned char, \ 85 nla_get_u8, NLA_PUT_U8) 86 #define __u16_field(attr_nr, attr_flag, name) \ 87 __field(attr_nr, attr_flag, name, NLA_U16, __u16, \ 88 nla_get_u16, NLA_PUT_U16) 89 #define __u32_field(attr_nr, attr_flag, name) \ 90 __field(attr_nr, attr_flag, name, NLA_U32, __u32, \ 91 nla_get_u32, NLA_PUT_U32) 92 #define __u64_field(attr_nr, attr_flag, name) \ 93 __field(attr_nr, attr_flag, name, NLA_U64, __u64, \ 94 nla_get_u64, NLA_PUT_U64) 95 #define __str_field(attr_nr, attr_flag, name, maxlen) \ 96 __array(attr_nr, attr_flag, name, NLA_NUL_STRING, char, maxlen, \ 97 nla_strlcpy, NLA_PUT) 98 #define __bin_field(attr_nr, attr_flag, name, maxlen) \ 99 __array(attr_nr, attr_flag, name, NLA_BINARY, char, maxlen, \ 100 nla_memcpy, NLA_PUT) 101 102 #define __nla_put_flag(skb, attrtype, value) \ 103 do { \ 104 if (value) \ 105 NLA_PUT_FLAG(skb, attrtype); \ 106 } while (0) 107 108 #define GENL_op_init(args...) args 109 #define GENL_doit(handler) \ 110 .doit = handler, \ 111 .flags = GENL_ADMIN_PERM, 112 #define GENL_dumpit(handler) \ 113 .dumpit = handler, \ 114 .flags = GENL_ADMIN_PERM, 115 116 /* }}}1 117 * Magic: define the enum symbols for genl_ops 118 * Magic: define the enum symbols for top level attributes 119 * Magic: define the enum symbols for nested attributes 120 * {{{2 121 */ 122 123 #undef GENL_struct 124 #define GENL_struct(tag_name, tag_number, s_name, s_fields) 125 126 #undef GENL_mc_group 127 #define GENL_mc_group(group) 128 129 #undef GENL_notification 130 #define GENL_notification(op_name, op_num, mcast_group, tla_list) \ 131 op_name = op_num, 132 133 #undef GENL_op 134 #define GENL_op(op_name, op_num, handler, tla_list) \ 135 op_name = op_num, 136 137 enum { 138 #include GENL_MAGIC_INCLUDE_FILE 139 }; 140 141 #undef GENL_notification 142 #define GENL_notification(op_name, op_num, mcast_group, tla_list) 143 144 #undef GENL_op 145 #define GENL_op(op_name, op_num, handler, attr_list) 146 147 #undef GENL_struct 148 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ 149 tag_name = tag_number, 150 151 enum { 152 #include GENL_MAGIC_INCLUDE_FILE 153 }; 154 155 #undef GENL_struct 156 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ 157 enum { \ 158 s_fields \ 159 }; 160 161 #undef __field 162 #define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put) \ 163 T_ ## name = (__u16)(attr_nr | attr_flag), 164 165 #undef __array 166 #define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, __get, __put) \ 167 T_ ## name = (__u16)(attr_nr | attr_flag), 168 169 #include GENL_MAGIC_INCLUDE_FILE 170 171 /* }}}1 172 * Magic: compile time assert unique numbers for operations 173 * Magic: -"- unique numbers for top level attributes 174 * Magic: -"- unique numbers for nested attributes 175 * {{{2 176 */ 177 178 #undef GENL_struct 179 #define GENL_struct(tag_name, tag_number, s_name, s_fields) 180 181 #undef GENL_op 182 #define GENL_op(op_name, op_num, handler, attr_list) \ 183 case op_name: 184 185 #undef GENL_notification 186 #define GENL_notification(op_name, op_num, mcast_group, tla_list) \ 187 case op_name: 188 189 static inline void ct_assert_unique_operations(void) 190 { 191 switch (0) { 192 #include GENL_MAGIC_INCLUDE_FILE 193 ; 194 } 195 } 196 197 #undef GENL_op 198 #define GENL_op(op_name, op_num, handler, attr_list) 199 200 #undef GENL_notification 201 #define GENL_notification(op_name, op_num, mcast_group, tla_list) 202 203 #undef GENL_struct 204 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ 205 case tag_number: 206 207 static inline void ct_assert_unique_top_level_attributes(void) 208 { 209 switch (0) { 210 #include GENL_MAGIC_INCLUDE_FILE 211 ; 212 } 213 } 214 215 #undef GENL_struct 216 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ 217 static inline void ct_assert_unique_ ## s_name ## _attributes(void) \ 218 { \ 219 switch (0) { \ 220 s_fields \ 221 ; \ 222 } \ 223 } 224 225 #undef __field 226 #define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put) \ 227 case attr_nr: 228 229 #undef __array 230 #define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, __get, __put) \ 231 case attr_nr: 232 233 #include GENL_MAGIC_INCLUDE_FILE 234 235 /* }}}1 236 * Magic: declare structs 237 * struct <name> { 238 * fields 239 * }; 240 * {{{2 241 */ 242 243 #undef GENL_struct 244 #define GENL_struct(tag_name, tag_number, s_name, s_fields) \ 245 struct s_name { s_fields }; 246 247 #undef __field 248 #define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put) \ 249 type name; 250 251 #undef __array 252 #define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, __get, __put) \ 253 type name[maxlen]; \ 254 __u32 name ## _len; 255 256 #include GENL_MAGIC_INCLUDE_FILE 257 258 /* }}}1 */ 259 #endif /* GENL_MAGIC_STRUCT_H */ 260 /* vim: set foldmethod=marker nofoldenable : */ 261