458 lines · c
1/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */2#ifndef __YNL_C_PRIV_H3#define __YNL_C_PRIV_H 14 5#include <stdbool.h>6#include <stddef.h>7#include <linux/types.h>8 9struct ynl_parse_arg;10 11/*12 * YNL internals / low level stuff13 */14 15enum ynl_policy_type {16 YNL_PT_REJECT = 1,17 YNL_PT_IGNORE,18 YNL_PT_NEST,19 YNL_PT_FLAG,20 YNL_PT_BINARY,21 YNL_PT_U8,22 YNL_PT_U16,23 YNL_PT_U32,24 YNL_PT_U64,25 YNL_PT_UINT,26 YNL_PT_NUL_STR,27 YNL_PT_BITFIELD32,28};29 30enum ynl_parse_result {31 YNL_PARSE_CB_ERROR = -1,32 YNL_PARSE_CB_STOP = 0,33 YNL_PARSE_CB_OK = 1,34};35 36#define YNL_SOCKET_BUFFER_SIZE (1 << 17)37 38#define YNL_ARRAY_SIZE(array) (sizeof(array) ? \39 sizeof(array) / sizeof(array[0]) : 0)40 41typedef int (*ynl_parse_cb_t)(const struct nlmsghdr *nlh,42 struct ynl_parse_arg *yarg);43 44struct ynl_policy_attr {45 enum ynl_policy_type type;46 unsigned int len;47 const char *name;48 const struct ynl_policy_nest *nest;49};50 51struct ynl_policy_nest {52 unsigned int max_attr;53 const struct ynl_policy_attr *table;54};55 56struct ynl_parse_arg {57 struct ynl_sock *ys;58 const struct ynl_policy_nest *rsp_policy;59 void *data;60};61 62struct ynl_dump_list_type {63 struct ynl_dump_list_type *next;64 unsigned char data[] __attribute__((aligned(8)));65};66extern struct ynl_dump_list_type *YNL_LIST_END;67 68static inline bool ynl_dump_obj_is_last(void *obj)69{70 unsigned long uptr = (unsigned long)obj;71 72 uptr -= offsetof(struct ynl_dump_list_type, data);73 return uptr == (unsigned long)YNL_LIST_END;74}75 76static inline void *ynl_dump_obj_next(void *obj)77{78 unsigned long uptr = (unsigned long)obj;79 struct ynl_dump_list_type *list;80 81 uptr -= offsetof(struct ynl_dump_list_type, data);82 list = (struct ynl_dump_list_type *)uptr;83 uptr = (unsigned long)list->next;84 uptr += offsetof(struct ynl_dump_list_type, data);85 86 return (void *)uptr;87}88 89struct ynl_ntf_base_type {90 __u16 family;91 __u8 cmd;92 struct ynl_ntf_base_type *next;93 void (*free)(struct ynl_ntf_base_type *ntf);94 unsigned char data[] __attribute__((aligned(8)));95};96 97struct nlmsghdr *98ynl_gemsg_start_req(struct ynl_sock *ys, __u32 id, __u8 cmd, __u8 version);99struct nlmsghdr *100ynl_gemsg_start_dump(struct ynl_sock *ys, __u32 id, __u8 cmd, __u8 version);101 102int ynl_attr_validate(struct ynl_parse_arg *yarg, const struct nlattr *attr);103 104/* YNL specific helpers used by the auto-generated code */105 106struct ynl_req_state {107 struct ynl_parse_arg yarg;108 ynl_parse_cb_t cb;109 __u32 rsp_cmd;110};111 112struct ynl_dump_state {113 struct ynl_parse_arg yarg;114 void *first;115 struct ynl_dump_list_type *last;116 size_t alloc_sz;117 ynl_parse_cb_t cb;118 __u32 rsp_cmd;119};120 121struct ynl_ntf_info {122 const struct ynl_policy_nest *policy;123 ynl_parse_cb_t cb;124 size_t alloc_sz;125 void (*free)(struct ynl_ntf_base_type *ntf);126};127 128int ynl_exec(struct ynl_sock *ys, struct nlmsghdr *req_nlh,129 struct ynl_req_state *yrs);130int ynl_exec_dump(struct ynl_sock *ys, struct nlmsghdr *req_nlh,131 struct ynl_dump_state *yds);132 133void ynl_error_unknown_notification(struct ynl_sock *ys, __u8 cmd);134int ynl_error_parse(struct ynl_parse_arg *yarg, const char *msg);135 136/* Netlink message handling helpers */137 138#define YNL_MSG_OVERFLOW 1139 140static inline struct nlmsghdr *ynl_nlmsg_put_header(void *buf)141{142 struct nlmsghdr *nlh = (struct nlmsghdr *)buf;143 144 memset(nlh, 0, sizeof(*nlh));145 nlh->nlmsg_len = NLMSG_HDRLEN;146 147 return nlh;148}149 150static inline unsigned int ynl_nlmsg_data_len(const struct nlmsghdr *nlh)151{152 return nlh->nlmsg_len - NLMSG_HDRLEN;153}154 155static inline void *ynl_nlmsg_data(const struct nlmsghdr *nlh)156{157 return (unsigned char *)nlh + NLMSG_HDRLEN;158}159 160static inline void *161ynl_nlmsg_data_offset(const struct nlmsghdr *nlh, unsigned int offset)162{163 return (unsigned char *)nlh + NLMSG_HDRLEN + offset;164}165 166static inline void *ynl_nlmsg_end_addr(const struct nlmsghdr *nlh)167{168 return (char *)nlh + nlh->nlmsg_len;169}170 171static inline void *172ynl_nlmsg_put_extra_header(struct nlmsghdr *nlh, unsigned int size)173{174 void *tail = ynl_nlmsg_end_addr(nlh);175 176 nlh->nlmsg_len += NLMSG_ALIGN(size);177 return tail;178}179 180/* Netlink attribute helpers */181 182static inline unsigned int ynl_attr_type(const struct nlattr *attr)183{184 return attr->nla_type & NLA_TYPE_MASK;185}186 187static inline unsigned int ynl_attr_data_len(const struct nlattr *attr)188{189 return attr->nla_len - NLA_HDRLEN;190}191 192static inline void *ynl_attr_data(const struct nlattr *attr)193{194 return (unsigned char *)attr + NLA_HDRLEN;195}196 197static inline void *ynl_attr_data_end(const struct nlattr *attr)198{199 return (char *)ynl_attr_data(attr) + ynl_attr_data_len(attr);200}201 202#define ynl_attr_for_each(attr, nlh, fixed_hdr_sz) \203 for ((attr) = ynl_attr_first(nlh, (nlh)->nlmsg_len, \204 NLMSG_HDRLEN + fixed_hdr_sz); attr; \205 (attr) = ynl_attr_next(ynl_nlmsg_end_addr(nlh), attr))206 207#define ynl_attr_for_each_nested(attr, outer) \208 for ((attr) = ynl_attr_first(outer, outer->nla_len, \209 sizeof(struct nlattr)); attr; \210 (attr) = ynl_attr_next(ynl_attr_data_end(outer), attr))211 212#define ynl_attr_for_each_payload(start, len, attr) \213 for ((attr) = ynl_attr_first(start, len, 0); attr; \214 (attr) = ynl_attr_next(start + len, attr))215 216static inline struct nlattr *217ynl_attr_if_good(const void *end, struct nlattr *attr)218{219 if (attr + 1 > (const struct nlattr *)end)220 return NULL;221 if (ynl_attr_data_end(attr) > end)222 return NULL;223 return attr;224}225 226static inline struct nlattr *227ynl_attr_next(const void *end, const struct nlattr *prev)228{229 struct nlattr *attr;230 231 attr = (struct nlattr *)((char *)prev + NLA_ALIGN(prev->nla_len));232 return ynl_attr_if_good(end, attr);233}234 235static inline struct nlattr *236ynl_attr_first(const void *start, size_t len, size_t skip)237{238 struct nlattr *attr;239 240 attr = (struct nlattr *)((char *)start + NLMSG_ALIGN(skip));241 return ynl_attr_if_good((char *)start + len, attr);242}243 244static inline bool245__ynl_attr_put_overflow(struct nlmsghdr *nlh, size_t size)246{247 bool o;248 249 /* ynl_msg_start() stashed buffer length in nlmsg_pid. */250 o = nlh->nlmsg_len + NLA_HDRLEN + NLMSG_ALIGN(size) > nlh->nlmsg_pid;251 if (o)252 /* YNL_MSG_OVERFLOW is < NLMSG_HDRLEN, all subsequent checks253 * are guaranteed to fail.254 */255 nlh->nlmsg_pid = YNL_MSG_OVERFLOW;256 return o;257}258 259static inline struct nlattr *260ynl_attr_nest_start(struct nlmsghdr *nlh, unsigned int attr_type)261{262 struct nlattr *attr;263 264 if (__ynl_attr_put_overflow(nlh, 0))265 return (struct nlattr *)ynl_nlmsg_end_addr(nlh) - 1;266 267 attr = (struct nlattr *)ynl_nlmsg_end_addr(nlh);268 attr->nla_type = attr_type | NLA_F_NESTED;269 nlh->nlmsg_len += NLA_HDRLEN;270 271 return attr;272}273 274static inline void275ynl_attr_nest_end(struct nlmsghdr *nlh, struct nlattr *attr)276{277 attr->nla_len = (char *)ynl_nlmsg_end_addr(nlh) - (char *)attr;278}279 280static inline void281ynl_attr_put(struct nlmsghdr *nlh, unsigned int attr_type,282 const void *value, size_t size)283{284 struct nlattr *attr;285 286 if (__ynl_attr_put_overflow(nlh, size))287 return;288 289 attr = (struct nlattr *)ynl_nlmsg_end_addr(nlh);290 attr->nla_type = attr_type;291 attr->nla_len = NLA_HDRLEN + size;292 293 memcpy(ynl_attr_data(attr), value, size);294 295 nlh->nlmsg_len += NLMSG_ALIGN(attr->nla_len);296}297 298static inline void299ynl_attr_put_str(struct nlmsghdr *nlh, unsigned int attr_type, const char *str)300{301 struct nlattr *attr;302 size_t len;303 304 len = strlen(str);305 if (__ynl_attr_put_overflow(nlh, len))306 return;307 308 attr = (struct nlattr *)ynl_nlmsg_end_addr(nlh);309 attr->nla_type = attr_type;310 311 strcpy((char *)ynl_attr_data(attr), str);312 attr->nla_len = NLA_HDRLEN + NLA_ALIGN(len);313 314 nlh->nlmsg_len += NLMSG_ALIGN(attr->nla_len);315}316 317static inline const char *ynl_attr_get_str(const struct nlattr *attr)318{319 return (const char *)ynl_attr_data(attr);320}321 322static inline __s8 ynl_attr_get_s8(const struct nlattr *attr)323{324 return *(__s8 *)ynl_attr_data(attr);325}326 327static inline __s16 ynl_attr_get_s16(const struct nlattr *attr)328{329 return *(__s16 *)ynl_attr_data(attr);330}331 332static inline __s32 ynl_attr_get_s32(const struct nlattr *attr)333{334 return *(__s32 *)ynl_attr_data(attr);335}336 337static inline __s64 ynl_attr_get_s64(const struct nlattr *attr)338{339 __s64 tmp;340 341 memcpy(&tmp, (unsigned char *)(attr + 1), sizeof(tmp));342 return tmp;343}344 345static inline __u8 ynl_attr_get_u8(const struct nlattr *attr)346{347 return *(__u8 *)ynl_attr_data(attr);348}349 350static inline __u16 ynl_attr_get_u16(const struct nlattr *attr)351{352 return *(__u16 *)ynl_attr_data(attr);353}354 355static inline __u32 ynl_attr_get_u32(const struct nlattr *attr)356{357 return *(__u32 *)ynl_attr_data(attr);358}359 360static inline __u64 ynl_attr_get_u64(const struct nlattr *attr)361{362 __u64 tmp;363 364 memcpy(&tmp, (unsigned char *)(attr + 1), sizeof(tmp));365 return tmp;366}367 368static inline void369ynl_attr_put_s8(struct nlmsghdr *nlh, unsigned int attr_type, __s8 value)370{371 ynl_attr_put(nlh, attr_type, &value, sizeof(value));372}373 374static inline void375ynl_attr_put_s16(struct nlmsghdr *nlh, unsigned int attr_type, __s16 value)376{377 ynl_attr_put(nlh, attr_type, &value, sizeof(value));378}379 380static inline void381ynl_attr_put_s32(struct nlmsghdr *nlh, unsigned int attr_type, __s32 value)382{383 ynl_attr_put(nlh, attr_type, &value, sizeof(value));384}385 386static inline void387ynl_attr_put_s64(struct nlmsghdr *nlh, unsigned int attr_type, __s64 value)388{389 ynl_attr_put(nlh, attr_type, &value, sizeof(value));390}391 392static inline void393ynl_attr_put_u8(struct nlmsghdr *nlh, unsigned int attr_type, __u8 value)394{395 ynl_attr_put(nlh, attr_type, &value, sizeof(value));396}397 398static inline void399ynl_attr_put_u16(struct nlmsghdr *nlh, unsigned int attr_type, __u16 value)400{401 ynl_attr_put(nlh, attr_type, &value, sizeof(value));402}403 404static inline void405ynl_attr_put_u32(struct nlmsghdr *nlh, unsigned int attr_type, __u32 value)406{407 ynl_attr_put(nlh, attr_type, &value, sizeof(value));408}409 410static inline void411ynl_attr_put_u64(struct nlmsghdr *nlh, unsigned int attr_type, __u64 value)412{413 ynl_attr_put(nlh, attr_type, &value, sizeof(value));414}415 416static inline __u64 ynl_attr_get_uint(const struct nlattr *attr)417{418 switch (ynl_attr_data_len(attr)) {419 case 4:420 return ynl_attr_get_u32(attr);421 case 8:422 return ynl_attr_get_u64(attr);423 default:424 return 0;425 }426}427 428static inline __s64 ynl_attr_get_sint(const struct nlattr *attr)429{430 switch (ynl_attr_data_len(attr)) {431 case 4:432 return ynl_attr_get_s32(attr);433 case 8:434 return ynl_attr_get_s64(attr);435 default:436 return 0;437 }438}439 440static inline void441ynl_attr_put_uint(struct nlmsghdr *nlh, __u16 type, __u64 data)442{443 if ((__u32)data == (__u64)data)444 ynl_attr_put_u32(nlh, type, data);445 else446 ynl_attr_put_u64(nlh, type, data);447}448 449static inline void450ynl_attr_put_sint(struct nlmsghdr *nlh, __u16 type, __s64 data)451{452 if ((__s32)data == (__s64)data)453 ynl_attr_put_s32(nlh, type, data);454 else455 ynl_attr_put_s64(nlh, type, data);456}457#endif458