1 #ifndef _LIBMNL_H_ 2 #define _LIBMNL_H_ 3 4 #include <stdbool.h> 5 #include <stdio.h> 6 #include <stdint.h> 7 #include <unistd.h> 8 #include <sys/socket.h> /* for sa_family_t */ 9 #include <linux/netlink.h> 10 11 #ifdef __cplusplus 12 extern "C" { 13 #endif 14 15 /* 16 * Netlink socket API 17 */ 18 19 #define MNL_SOCKET_AUTOPID 0 20 #define MNL_SOCKET_BUFFER_SIZE (sysconf(_SC_PAGESIZE) < 8192L ? sysconf(_SC_PAGESIZE) : 8192L) 21 #define MNL_SOCKET_DUMP_SIZE 32768 22 23 struct mnl_socket; 24 25 extern struct mnl_socket *mnl_socket_open(int bus); 26 extern struct mnl_socket *mnl_socket_open2(int bus, int flags); 27 extern struct mnl_socket *mnl_socket_fdopen(int fd); 28 extern int mnl_socket_bind(struct mnl_socket *nl, unsigned int groups, pid_t pid); 29 extern int mnl_socket_close(struct mnl_socket *nl); 30 extern int mnl_socket_get_fd(const struct mnl_socket *nl); 31 extern unsigned int mnl_socket_get_portid(const struct mnl_socket *nl); 32 extern ssize_t mnl_socket_sendto(const struct mnl_socket *nl, const void *req, size_t siz); 33 extern ssize_t mnl_socket_recvfrom(const struct mnl_socket *nl, void *buf, size_t siz); 34 extern int mnl_socket_setsockopt(const struct mnl_socket *nl, int type, void *buf, socklen_t len); 35 extern int mnl_socket_getsockopt(const struct mnl_socket *nl, int type, void *buf, socklen_t *len); 36 37 /* 38 * Netlink message API 39 */ 40 41 #define MNL_ALIGNTO 4 42 #define MNL_ALIGN(len) (((len)+MNL_ALIGNTO-1) & ~(MNL_ALIGNTO-1)) 43 #define MNL_NLMSG_HDRLEN MNL_ALIGN(sizeof(struct nlmsghdr)) 44 45 extern size_t mnl_nlmsg_size(size_t len); 46 extern size_t mnl_nlmsg_get_payload_len(const struct nlmsghdr *nlh); 47 48 /* Netlink message header builder */ 49 extern struct nlmsghdr *mnl_nlmsg_put_header(void *buf); 50 extern void *mnl_nlmsg_put_extra_header(struct nlmsghdr *nlh, size_t size); 51 52 /* Netlink message iterators */ 53 extern bool mnl_nlmsg_ok(const struct nlmsghdr *nlh, int len); 54 extern struct nlmsghdr *mnl_nlmsg_next(const struct nlmsghdr *nlh, int *len); 55 56 /* Netlink sequence tracking */ 57 extern bool mnl_nlmsg_seq_ok(const struct nlmsghdr *nlh, unsigned int seq); 58 59 /* Netlink portID checking */ 60 extern bool mnl_nlmsg_portid_ok(const struct nlmsghdr *nlh, unsigned int portid); 61 62 /* Netlink message getters */ 63 extern void *mnl_nlmsg_get_payload(const struct nlmsghdr *nlh); 64 extern void *mnl_nlmsg_get_payload_offset(const struct nlmsghdr *nlh, size_t offset); 65 extern void *mnl_nlmsg_get_payload_tail(const struct nlmsghdr *nlh); 66 67 /* Netlink message printer */ 68 extern void mnl_nlmsg_fprintf(FILE *fd, const void *data, size_t datalen, size_t extra_header_size); 69 70 /* Message batch helpers */ 71 struct mnl_nlmsg_batch; 72 extern struct mnl_nlmsg_batch *mnl_nlmsg_batch_start(void *buf, size_t bufsiz); 73 extern bool mnl_nlmsg_batch_next(struct mnl_nlmsg_batch *b); 74 extern void mnl_nlmsg_batch_stop(struct mnl_nlmsg_batch *b); 75 extern size_t mnl_nlmsg_batch_size(struct mnl_nlmsg_batch *b); 76 extern void mnl_nlmsg_batch_reset(struct mnl_nlmsg_batch *b); 77 extern void *mnl_nlmsg_batch_head(struct mnl_nlmsg_batch *b); 78 extern void *mnl_nlmsg_batch_current(struct mnl_nlmsg_batch *b); 79 extern bool mnl_nlmsg_batch_is_empty(struct mnl_nlmsg_batch *b); 80 81 /* 82 * Netlink attributes API 83 */ 84 #define MNL_ATTR_HDRLEN MNL_ALIGN(sizeof(struct nlattr)) 85 86 /* TLV attribute getters */ 87 extern uint16_t mnl_attr_get_type(const struct nlattr *attr); 88 extern uint16_t mnl_attr_get_len(const struct nlattr *attr); 89 extern uint16_t mnl_attr_get_payload_len(const struct nlattr *attr); 90 extern void *mnl_attr_get_payload(const struct nlattr *attr); 91 extern uint8_t mnl_attr_get_u8(const struct nlattr *attr); 92 extern uint16_t mnl_attr_get_u16(const struct nlattr *attr); 93 extern uint32_t mnl_attr_get_u32(const struct nlattr *attr); 94 extern uint64_t mnl_attr_get_u64(const struct nlattr *attr); 95 extern const char *mnl_attr_get_str(const struct nlattr *attr); 96 97 /* TLV attribute putters */ 98 extern void mnl_attr_put(struct nlmsghdr *nlh, uint16_t type, size_t len, const void *data); 99 extern void mnl_attr_put_u8(struct nlmsghdr *nlh, uint16_t type, uint8_t data); 100 extern void mnl_attr_put_u16(struct nlmsghdr *nlh, uint16_t type, uint16_t data); 101 extern void mnl_attr_put_u32(struct nlmsghdr *nlh, uint16_t type, uint32_t data); 102 extern void mnl_attr_put_u64(struct nlmsghdr *nlh, uint16_t type, uint64_t data); 103 extern void mnl_attr_put_str(struct nlmsghdr *nlh, uint16_t type, const char *data); 104 extern void mnl_attr_put_strz(struct nlmsghdr *nlh, uint16_t type, const char *data); 105 106 /* TLV attribute putters with buffer boundary checkings */ 107 extern bool mnl_attr_put_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, size_t len, const void *data); 108 extern bool mnl_attr_put_u8_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, uint8_t data); 109 extern bool mnl_attr_put_u16_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, uint16_t data); 110 extern bool mnl_attr_put_u32_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, uint32_t data); 111 extern bool mnl_attr_put_u64_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, uint64_t data); 112 extern bool mnl_attr_put_str_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, const char *data); 113 extern bool mnl_attr_put_strz_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type, const char *data); 114 115 /* TLV attribute nesting */ 116 extern struct nlattr *mnl_attr_nest_start(struct nlmsghdr *nlh, uint16_t type); 117 extern struct nlattr *mnl_attr_nest_start_check(struct nlmsghdr *nlh, size_t buflen, uint16_t type); 118 extern void mnl_attr_nest_end(struct nlmsghdr *nlh, struct nlattr *start); 119 extern void mnl_attr_nest_cancel(struct nlmsghdr *nlh, struct nlattr *start); 120 121 /* TLV validation */ 122 extern int mnl_attr_type_valid(const struct nlattr *attr, uint16_t maxtype); 123 124 enum mnl_attr_data_type { 125 MNL_TYPE_UNSPEC, 126 MNL_TYPE_U8, 127 MNL_TYPE_U16, 128 MNL_TYPE_U32, 129 MNL_TYPE_U64, 130 MNL_TYPE_STRING, 131 MNL_TYPE_FLAG, 132 MNL_TYPE_MSECS, 133 MNL_TYPE_NESTED, 134 MNL_TYPE_NESTED_COMPAT, 135 MNL_TYPE_NUL_STRING, 136 MNL_TYPE_BINARY, 137 MNL_TYPE_MAX, 138 }; 139 140 extern int mnl_attr_validate(const struct nlattr *attr, enum mnl_attr_data_type type); 141 extern int mnl_attr_validate2(const struct nlattr *attr, enum mnl_attr_data_type type, size_t len); 142 143 /* TLV iterators */ 144 extern bool mnl_attr_ok(const struct nlattr *attr, int len); 145 extern struct nlattr *mnl_attr_next(const struct nlattr *attr); 146 147 #define mnl_attr_for_each(attr, nlh, offset) \ 148 for ((attr) = mnl_nlmsg_get_payload_offset((nlh), (offset)); \ 149 mnl_attr_ok((attr), (char *)mnl_nlmsg_get_payload_tail(nlh) - (char *)(attr)); \ 150 (attr) = mnl_attr_next(attr)) 151 152 #define mnl_attr_for_each_nested(attr, nest) \ 153 for ((attr) = mnl_attr_get_payload(nest); \ 154 mnl_attr_ok((attr), (char *)mnl_attr_get_payload(nest) + mnl_attr_get_payload_len(nest) - (char *)(attr)); \ 155 (attr) = mnl_attr_next(attr)) 156 157 #define mnl_attr_for_each_payload(payload, payload_size) \ 158 for ((attr) = (payload); \ 159 mnl_attr_ok((attr), (char *)(payload) + payload_size - (char *)(attr)); \ 160 (attr) = mnl_attr_next(attr)) 161 162 /* TLV callback-based attribute parsers */ 163 typedef int (*mnl_attr_cb_t)(const struct nlattr *attr, void *data); 164 165 extern int mnl_attr_parse(const struct nlmsghdr *nlh, unsigned int offset, mnl_attr_cb_t cb, void *data); 166 extern int mnl_attr_parse_nested(const struct nlattr *attr, mnl_attr_cb_t cb, void *data); 167 extern int mnl_attr_parse_payload(const void *payload, size_t payload_len, mnl_attr_cb_t cb, void *data); 168 169 /* 170 * callback API 171 */ 172 #define MNL_CB_ERROR -1 173 #define MNL_CB_STOP 0 174 #define MNL_CB_OK 1 175 176 typedef int (*mnl_cb_t)(const struct nlmsghdr *nlh, void *data); 177 178 extern int mnl_cb_run(const void *buf, size_t numbytes, unsigned int seq, 179 unsigned int portid, mnl_cb_t cb_data, void *data); 180 181 extern int mnl_cb_run2(const void *buf, size_t numbytes, unsigned int seq, 182 unsigned int portid, mnl_cb_t cb_data, void *data, 183 const mnl_cb_t *cb_ctl_array, 184 unsigned int cb_ctl_array_len); 185 186 /* 187 * other declarations 188 */ 189 190 #ifndef SOL_NETLINK 191 #define SOL_NETLINK 270 192 #endif 193 194 #ifndef MNL_ARRAY_SIZE 195 #define MNL_ARRAY_SIZE(a) (sizeof(a)/sizeof((a)[0])) 196 #endif 197 198 #ifdef __cplusplus 199 } /* extern "C" */ 200 #endif 201 202 #endif 203