2 * SPDX-License-Identifier: BSD-2-Clause
4 * Copyright (c) 2022 Alexander V. Chernikov <melifaro@FreeBSD.org>
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 #ifndef _NETLINK_NETLINK_SNL_H_
28 #define _NETLINK_NETLINK_SNL_H_
31 * Simple Netlink Library
43 #include <sys/types.h>
44 #include <sys/socket.h>
45 #include <netlink/netlink.h>
46 #include <netlink/netlink_bitset.h>
48 #define _roundup2(x, y) (((x)+((y)-1))&(~((y)-1)))
50 #define NETLINK_ALIGN_SIZE sizeof(uint32_t)
51 #define NETLINK_ALIGN(_len) _roundup2(_len, NETLINK_ALIGN_SIZE)
53 #define NLA_ALIGN_SIZE sizeof(uint32_t)
54 #define NLA_HDRLEN ((int)sizeof(struct nlattr))
55 #define NLA_DATA_LEN(_nla) ((int)((_nla)->nla_len - NLA_HDRLEN))
56 #define NLA_DATA(_nla) NL_ITEM_DATA(_nla, NLA_HDRLEN)
57 #define NLA_DATA_CONST(_nla) NL_ITEM_DATA_CONST(_nla, NLA_HDRLEN)
59 #define NLA_TYPE(_nla) ((_nla)->nla_type & 0x3FFF)
61 #define NLA_NEXT(_attr) (struct nlattr *)(void *)((char *)_attr + NLA_ALIGN(_attr->nla_len))
63 #define _NLA_END(_start, _len) ((char *)(_start) + (_len))
64 #define NLA_FOREACH(_attr, _start, _len) \
65 for (_attr = (_start); \
66 ((char *)_attr < _NLA_END(_start, _len)) && \
67 ((char *)NLA_NEXT(_attr) <= _NLA_END(_start, _len)); \
68 _attr = NLA_NEXT(_attr))
70 #define NL_ARRAY_LEN(_a) (sizeof(_a) / sizeof((_a)[0]))
72 struct linear_buffer {
73 char *base; /* Base allocated memory pointer */
74 uint32_t offset; /* Currently used offset */
75 uint32_t size; /* Total buffer size */
76 struct linear_buffer *next; /* Buffer chaining */
79 static inline struct linear_buffer *
80 lb_init(uint32_t size)
82 struct linear_buffer *lb = calloc(1, size);
85 lb->base = (char *)(lb + 1);
86 lb->size = size - sizeof(*lb);
93 lb_free(struct linear_buffer *lb)
99 lb_allocz(struct linear_buffer *lb, int len)
101 len = roundup2(len, sizeof(uint64_t));
102 if (lb->offset + len > lb->size)
104 void *data = (void *)(lb->base + lb->offset);
110 lb_clear(struct linear_buffer *lb)
112 memset(lb->base, 0, lb->offset);
124 struct linear_buffer *lb;
126 #define SCRATCH_BUFFER_SIZE 1024
127 #define SNL_WRITER_BUFFER_SIZE 256
129 typedef void snl_parse_field_f(struct snl_state *ss, void *hdr, void *target);
130 struct snl_field_parser {
133 snl_parse_field_f *cb;
136 typedef bool snl_parse_attr_f(struct snl_state *ss, struct nlattr *attr,
137 const void *arg, void *target);
138 struct snl_attr_parser {
139 uint16_t type; /* Attribute type */
140 uint16_t off; /* field offset in the target structure */
141 snl_parse_attr_f *cb; /* parser function to call */
143 /* Optional parser argument */
146 const uint32_t arg_u32;
150 typedef bool snl_parse_post_f(struct snl_state *ss, void *target);
152 struct snl_hdr_parser {
153 uint16_t in_hdr_size; /* Input header size */
154 uint16_t out_size; /* Output structure size */
155 uint16_t fp_size; /* Number of items in field parser */
156 uint16_t np_size; /* Number of items in attribute parser */
157 const struct snl_field_parser *fp; /* array of header field parsers */
158 const struct snl_attr_parser *np; /* array of attribute parsers */
159 snl_parse_post_f *cb_post; /* post-parse callback */
162 #define SNL_DECLARE_PARSER_EXT(_name, _sz_h_in, _sz_out, _fp, _np, _cb) \
163 static const struct snl_hdr_parser _name = { \
164 .in_hdr_size = _sz_h_in, \
165 .out_size = _sz_out, \
168 .fp_size = NL_ARRAY_LEN(_fp), \
169 .np_size = NL_ARRAY_LEN(_np), \
173 #define SNL_DECLARE_PARSER(_name, _t, _fp, _np) \
174 SNL_DECLARE_PARSER_EXT(_name, sizeof(_t), 0, _fp, _np, NULL)
176 #define SNL_DECLARE_ATTR_PARSER_EXT(_name, _sz_out, _np, _cb) \
177 static const struct snl_hdr_parser _name = { \
178 .out_size = _sz_out, \
180 .np_size = NL_ARRAY_LEN(_np), \
184 #define SNL_DECLARE_ATTR_PARSER(_name, _np) \
185 SNL_DECLARE_ATTR_PARSER_EXT(_name, 0, _np, NULL)
189 snl_allocz(struct snl_state *ss, int len)
191 void *data = lb_allocz(ss->lb, len);
194 uint32_t size = ss->lb->size * 2;
196 while (size < len + sizeof(struct linear_buffer))
199 struct linear_buffer *lb = lb_init(size);
204 data = lb_allocz(ss->lb, len);
212 snl_clear_lb(struct snl_state *ss)
214 struct linear_buffer *lb = ss->lb;
219 /* Remove all linear bufs except the largest one */
221 struct linear_buffer *lb_next = lb->next;
228 snl_free(struct snl_state *ss)
234 if (ss->lb != NULL) {
242 snl_init(struct snl_state *ss, int netlink_family)
244 memset(ss, 0, sizeof(*ss));
246 ss->fd = socket(AF_NETLINK, SOCK_RAW, netlink_family);
249 ss->init_done = true;
252 socklen_t optlen = sizeof(val);
253 if (setsockopt(ss->fd, SOL_NETLINK, NETLINK_EXT_ACK, &val, optlen) == -1) {
259 if (getsockopt(ss->fd, SOL_SOCKET, SO_RCVBUF, &rcvbuf, &optlen) == -1) {
264 ss->bufsize = rcvbuf;
265 ss->buf = malloc(ss->bufsize);
266 if (ss->buf == NULL) {
271 ss->lb = lb_init(SCRATCH_BUFFER_SIZE);
272 if (ss->lb == NULL) {
281 snl_send(struct snl_state *ss, void *data, int sz)
283 return (send(ss->fd, data, sz, 0) == sz);
287 snl_send_message(struct snl_state *ss, struct nlmsghdr *hdr)
289 ssize_t sz = NLMSG_ALIGN(hdr->nlmsg_len);
291 return (send(ss->fd, hdr, sz, 0) == sz);
294 static inline uint32_t
295 snl_get_seq(struct snl_state *ss)
300 struct snl_msg_info {
307 static inline bool parse_cmsg(struct snl_state *ss, const struct msghdr *msg,
308 struct snl_msg_info *attrs);
310 static inline struct nlmsghdr *
311 snl_read_message_dbg(struct snl_state *ss, struct snl_msg_info *cinfo)
313 memset(cinfo, 0, sizeof(*cinfo));
315 if (ss->off == ss->datalen) {
316 struct sockaddr_nl nladdr;
321 .iov_len = ss->bufsize,
323 struct msghdr msg = {
325 .msg_namelen = sizeof(nladdr),
329 .msg_controllen = sizeof(cbuf),
334 ssize_t datalen = recvmsg(ss->fd, &msg, 0);
336 ss->datalen = datalen;
337 parse_cmsg(ss, &msg, cinfo);
339 } else if (errno != EINTR)
343 struct nlmsghdr *hdr = (struct nlmsghdr *)(void *)&ss->buf[ss->off];
344 ss->off += NLMSG_ALIGN(hdr->nlmsg_len);
349 static inline struct nlmsghdr *
350 snl_read_message(struct snl_state *ss)
352 if (ss->off == ss->datalen) {
353 struct sockaddr_nl nladdr;
356 .iov_len = ss->bufsize,
358 struct msghdr msg = {
360 .msg_namelen = sizeof(nladdr),
367 ssize_t datalen = recvmsg(ss->fd, &msg, 0);
369 ss->datalen = datalen;
371 } else if (errno != EINTR)
375 struct nlmsghdr *hdr = (struct nlmsghdr *)(void *)&ss->buf[ss->off];
376 ss->off += NLMSG_ALIGN(hdr->nlmsg_len);
380 static inline struct nlmsghdr *
381 snl_read_reply(struct snl_state *ss, uint32_t nlmsg_seq)
383 struct nlmsghdr *hdr;
385 while ((hdr = snl_read_message(ss)) != NULL) {
386 if (hdr->nlmsg_seq == nlmsg_seq)
394 * Checks that attributes are sorted by attribute type.
397 snl_verify_parsers(const struct snl_hdr_parser **parser, int count)
399 for (int i = 0; i < count; i++) {
400 const struct snl_hdr_parser *p = parser[i];
402 for (int j = 0; j < p->np_size; j++) {
403 assert(p->np[j].type > attr_type);
404 attr_type = p->np[j].type;
408 #define SNL_VERIFY_PARSERS(_p) snl_verify_parsers((_p), NL_ARRAY_LEN(_p))
410 static const struct snl_attr_parser *
411 find_parser(const struct snl_attr_parser *ps, int pslen, int key)
413 int left_i = 0, right_i = pslen - 1;
415 if (key < ps[0].type || key > ps[pslen - 1].type)
418 while (left_i + 1 < right_i) {
419 int mid_i = (left_i + right_i) / 2;
420 if (key < ps[mid_i].type)
422 else if (key > ps[mid_i].type)
427 if (ps[left_i].type == key)
428 return (&ps[left_i]);
429 else if (ps[right_i].type == key)
430 return (&ps[right_i]);
435 snl_parse_attrs_raw(struct snl_state *ss, struct nlattr *nla_head, int len,
436 const struct snl_attr_parser *ps, int pslen, void *target)
440 NLA_FOREACH(nla, nla_head, len) {
441 if (nla->nla_len < sizeof(struct nlattr))
443 int nla_type = nla->nla_type & NLA_TYPE_MASK;
444 const struct snl_attr_parser *s = find_parser(ps, pslen, nla_type);
446 void *ptr = (void *)((char *)target + s->off);
447 if (!s->cb(ss, nla, s->arg, ptr))
455 snl_parse_attrs(struct snl_state *ss, struct nlmsghdr *hdr, int hdrlen,
456 const struct snl_attr_parser *ps, int pslen, void *target)
458 int off = NLMSG_HDRLEN + NETLINK_ALIGN(hdrlen);
459 int len = hdr->nlmsg_len - off;
460 struct nlattr *nla_head = (struct nlattr *)(void *)((char *)hdr + off);
462 return (snl_parse_attrs_raw(ss, nla_head, len, ps, pslen, target));
466 snl_parse_fields(struct snl_state *ss, struct nlmsghdr *hdr, int hdrlen __unused,
467 const struct snl_field_parser *ps, int pslen, void *target)
469 for (int i = 0; i < pslen; i++) {
470 const struct snl_field_parser *fp = &ps[i];
471 void *src = (char *)hdr + fp->off_in;
472 void *dst = (char *)target + fp->off_out;
474 fp->cb(ss, src, dst);
479 snl_parse_header(struct snl_state *ss, void *hdr, int len,
480 const struct snl_hdr_parser *parser, void *target)
482 struct nlattr *nla_head;
484 /* Extract fields first (if any) */
485 snl_parse_fields(ss, hdr, parser->in_hdr_size, parser->fp, parser->fp_size, target);
487 nla_head = (struct nlattr *)(void *)((char *)hdr + parser->in_hdr_size);
488 bool result = snl_parse_attrs_raw(ss, nla_head, len - parser->in_hdr_size,
489 parser->np, parser->np_size, target);
491 if (result && parser->cb_post != NULL)
492 result = parser->cb_post(ss, target);
498 snl_parse_nlmsg(struct snl_state *ss, struct nlmsghdr *hdr,
499 const struct snl_hdr_parser *parser, void *target)
501 return (snl_parse_header(ss, hdr + 1, hdr->nlmsg_len - sizeof(*hdr), parser, target));
505 snl_attr_get_flag(struct snl_state *ss __unused, struct nlattr *nla, const void *arg __unused,
508 if (NLA_DATA_LEN(nla) == 0) {
509 *((uint8_t *)target) = 1;
516 snl_attr_get_uint8(struct snl_state *ss __unused, struct nlattr *nla,
517 const void *arg __unused, void *target)
519 if (NLA_DATA_LEN(nla) == sizeof(uint8_t)) {
520 *((uint8_t *)target) = *((const uint8_t *)NLA_DATA_CONST(nla));
527 snl_attr_get_uint16(struct snl_state *ss __unused, struct nlattr *nla,
528 const void *arg __unused, void *target)
530 if (NLA_DATA_LEN(nla) == sizeof(uint16_t)) {
531 *((uint16_t *)target) = *((const uint16_t *)NLA_DATA_CONST(nla));
538 snl_attr_get_uint32(struct snl_state *ss __unused, struct nlattr *nla,
539 const void *arg __unused, void *target)
541 if (NLA_DATA_LEN(nla) == sizeof(uint32_t)) {
542 *((uint32_t *)target) = *((const uint32_t *)NLA_DATA_CONST(nla));
549 snl_attr_get_uint64(struct snl_state *ss __unused, struct nlattr *nla,
550 const void *arg __unused, void *target)
552 if (NLA_DATA_LEN(nla) == sizeof(uint64_t)) {
553 memcpy(target, NLA_DATA_CONST(nla), sizeof(uint64_t));
560 snl_attr_get_int8(struct snl_state *ss, struct nlattr *nla, const void *arg,
563 return (snl_attr_get_uint8(ss, nla, arg, target));
567 snl_attr_get_int16(struct snl_state *ss, struct nlattr *nla, const void *arg,
570 return (snl_attr_get_uint16(ss, nla, arg, target));
574 snl_attr_get_int32(struct snl_state *ss, struct nlattr *nla, const void *arg,
577 return (snl_attr_get_uint32(ss, nla, arg, target));
581 snl_attr_get_int64(struct snl_state *ss, struct nlattr *nla, const void *arg,
584 return (snl_attr_get_uint64(ss, nla, arg, target));
588 snl_attr_get_string(struct snl_state *ss __unused, struct nlattr *nla,
589 const void *arg __unused, void *target)
591 size_t maxlen = NLA_DATA_LEN(nla);
593 if (strnlen((char *)NLA_DATA(nla), maxlen) < maxlen) {
594 *((char **)target) = (char *)NLA_DATA(nla);
601 snl_attr_get_stringn(struct snl_state *ss, struct nlattr *nla,
602 const void *arg __unused, void *target)
604 int maxlen = NLA_DATA_LEN(nla);
606 char *buf = snl_allocz(ss, maxlen + 1);
610 memcpy(buf, NLA_DATA(nla), maxlen);
612 *((char **)target) = buf;
617 snl_attr_copy_string(struct snl_state *ss, struct nlattr *nla,
618 const void *arg, void *target)
622 if (snl_attr_get_string(ss, nla, NULL, &tmp)) {
623 strlcpy(target, tmp, (size_t)arg);
630 snl_attr_dup_string(struct snl_state *ss __unused, struct nlattr *nla,
631 const void *arg __unused, void *target)
633 size_t maxlen = NLA_DATA_LEN(nla);
635 if (strnlen((char *)NLA_DATA(nla), maxlen) < maxlen) {
636 char *buf = snl_allocz(ss, maxlen);
639 memcpy(buf, NLA_DATA(nla), maxlen);
640 *((char **)target) = buf;
647 snl_attr_get_nested(struct snl_state *ss, struct nlattr *nla, const void *arg, void *target)
649 const struct snl_hdr_parser *p = (const struct snl_hdr_parser *)arg;
651 /* Assumes target points to the beginning of the structure */
652 return (snl_parse_header(ss, NLA_DATA(nla), NLA_DATA_LEN(nla), p, target));
661 snl_attr_get_parray_sz(struct snl_state *ss, struct nlattr *container_nla,
662 uint32_t start_size, const void *arg, void *target)
664 const struct snl_hdr_parser *p = (const struct snl_hdr_parser *)arg;
665 struct snl_parray *array = target;
667 uint32_t count = 0, size = start_size;
669 if (p->out_size == 0)
672 array->items = snl_allocz(ss, size * sizeof(void *));
673 if (array->items == NULL)
677 * If the provided parser is an attribute parser, assume that each
678 * nla in the container nla is the container nla itself and parse
679 * the contents of this nla.
680 * Otherwise, run the parser on raw data, assuming the header of this
681 * data has u16 field with total size in the beginning.
683 uint32_t data_off = 0;
685 if (p->in_hdr_size == 0)
686 data_off = sizeof(struct nlattr);
688 NLA_FOREACH(nla, NLA_DATA(container_nla), NLA_DATA_LEN(container_nla)) {
689 void *item = snl_allocz(ss, p->out_size);
694 void *data = (char *)(void *)nla + data_off;
695 int data_len = nla->nla_len - data_off;
697 if (!(snl_parse_header(ss, data, data_len, p, item)))
701 uint32_t new_size = size * 2;
702 void **new_array = snl_allocz(ss, new_size *sizeof(void *));
704 memcpy(new_array, array->items, size * sizeof(void *));
705 array->items = new_array;
708 array->items[count++] = item;
710 array->count = count;
716 * Parses and stores the unknown-size array.
717 * Assumes each array item is a container and the NLAs in the container are parsable
718 * by the parser provided in @arg.
719 * Assumes @target is struct snl_parray
722 snl_attr_get_parray(struct snl_state *ss, struct nlattr *nla, const void *arg, void *target)
724 return (snl_attr_get_parray_sz(ss, nla, 8, arg, target));
728 snl_attr_get_nla(struct snl_state *ss __unused, struct nlattr *nla,
729 const void *arg __unused, void *target)
731 *((struct nlattr **)target) = nla;
736 snl_attr_dup_nla(struct snl_state *ss, struct nlattr *nla,
737 const void *arg __unused, void *target)
739 void *ptr = snl_allocz(ss, nla->nla_len);
742 memcpy(ptr, nla, nla->nla_len);
743 *((void **)target) = ptr;
750 snl_attr_copy_struct(struct snl_state *ss, struct nlattr *nla,
751 const void *arg __unused, void *target)
753 void *ptr = snl_allocz(ss, NLA_DATA_LEN(nla));
756 memcpy(ptr, NLA_DATA(nla), NLA_DATA_LEN(nla));
757 *((void **)target) = ptr;
764 snl_attr_dup_struct(struct snl_state *ss, struct nlattr *nla,
765 const void *arg __unused, void *target)
767 void *ptr = snl_allocz(ss, NLA_DATA_LEN(nla));
770 memcpy(ptr, NLA_DATA(nla), NLA_DATA_LEN(nla));
771 *((void **)target) = ptr;
777 struct snl_attr_bit {
783 struct snl_attr_bits {
785 struct snl_attr_bit **bits;
788 #define _OUT(_field) offsetof(struct snl_attr_bit, _field)
789 static const struct snl_attr_parser _nla_p_bit[] = {
790 { .type = NLA_BITSET_BIT_INDEX, .off = _OUT(bit_index), .cb = snl_attr_get_uint32 },
791 { .type = NLA_BITSET_BIT_NAME, .off = _OUT(bit_name), .cb = snl_attr_dup_string },
792 { .type = NLA_BITSET_BIT_VALUE, .off = _OUT(bit_value), .cb = snl_attr_get_flag },
795 SNL_DECLARE_ATTR_PARSER_EXT(_nla_bit_parser, sizeof(struct snl_attr_bit), _nla_p_bit, NULL);
797 struct snl_attr_bitset {
798 uint32_t nla_bitset_size;
799 uint32_t *nla_bitset_mask;
800 uint32_t *nla_bitset_value;
801 struct snl_attr_bits bits;
804 #define _OUT(_field) offsetof(struct snl_attr_bitset, _field)
805 static const struct snl_attr_parser _nla_p_bitset[] = {
806 { .type = NLA_BITSET_SIZE, .off = _OUT(nla_bitset_size), .cb = snl_attr_get_uint32 },
807 { .type = NLA_BITSET_BITS, .off = _OUT(bits), .cb = snl_attr_get_parray, .arg = &_nla_bit_parser },
808 { .type = NLA_BITSET_VALUE, .off = _OUT(nla_bitset_mask), .cb = snl_attr_dup_nla },
809 { .type = NLA_BITSET_MASK, .off = _OUT(nla_bitset_value), .cb = snl_attr_dup_nla },
813 _cb_p_bitset(struct snl_state *ss __unused, void *_target)
815 struct snl_attr_bitset *target = _target;
817 uint32_t sz_bytes = _roundup2(target->nla_bitset_size, 32) / 8;
819 if (target->nla_bitset_mask != NULL) {
820 struct nlattr *nla = (struct nlattr *)target->nla_bitset_mask;
821 uint32_t data_len = NLA_DATA_LEN(nla);
823 if (data_len != sz_bytes || _roundup2(data_len, 4) != data_len)
825 target->nla_bitset_mask = (uint32_t *)NLA_DATA(nla);
828 if (target->nla_bitset_value != NULL) {
829 struct nlattr *nla = (struct nlattr *)target->nla_bitset_value;
830 uint32_t data_len = NLA_DATA_LEN(nla);
832 if (data_len != sz_bytes || _roundup2(data_len, 4) != data_len)
834 target->nla_bitset_value = (uint32_t *)NLA_DATA(nla);
839 SNL_DECLARE_ATTR_PARSER_EXT(_nla_bitset_parser,
840 sizeof(struct snl_attr_bitset),
841 _nla_p_bitset, _cb_p_bitset);
844 * Parses the compact bitset representation.
847 snl_attr_get_bitset_c(struct snl_state *ss, struct nlattr *nla,
848 const void *arg __unused, void *_target)
850 const struct snl_hdr_parser *p = &_nla_bitset_parser;
851 struct snl_attr_bitset *target = _target;
853 /* Assumes target points to the beginning of the structure */
854 if (!snl_parse_header(ss, NLA_DATA(nla), NLA_DATA_LEN(nla), p, _target))
856 if (target->nla_bitset_mask == NULL || target->nla_bitset_value == NULL)
862 snl_field_get_uint8(struct snl_state *ss __unused, void *src, void *target)
864 *((uint8_t *)target) = *((uint8_t *)src);
868 snl_field_get_uint16(struct snl_state *ss __unused, void *src, void *target)
870 *((uint16_t *)target) = *((uint16_t *)src);
874 snl_field_get_uint32(struct snl_state *ss __unused, void *src, void *target)
876 *((uint32_t *)target) = *((uint32_t *)src);
880 snl_field_get_ptr(struct snl_state *ss __unused, void *src, void *target)
882 *((void **)target) = src;
885 struct snl_errmsg_data {
886 struct nlmsghdr *orig_hdr;
890 struct nlattr *cookie;
893 #define _IN(_field) offsetof(struct nlmsgerr, _field)
894 #define _OUT(_field) offsetof(struct snl_errmsg_data, _field)
895 static const struct snl_attr_parser nla_p_errmsg[] = {
896 { .type = NLMSGERR_ATTR_MSG, .off = _OUT(error_str), .cb = snl_attr_get_string },
897 { .type = NLMSGERR_ATTR_OFFS, .off = _OUT(error_offs), .cb = snl_attr_get_uint32 },
898 { .type = NLMSGERR_ATTR_COOKIE, .off = _OUT(cookie), .cb = snl_attr_get_nla },
901 static const struct snl_field_parser nlf_p_errmsg[] = {
902 { .off_in = _IN(error), .off_out = _OUT(error), .cb = snl_field_get_uint32 },
903 { .off_in = _IN(msg), .off_out = _OUT(orig_hdr), .cb = snl_field_get_ptr },
907 SNL_DECLARE_PARSER(snl_errmsg_parser, struct nlmsgerr, nlf_p_errmsg, nla_p_errmsg);
909 #define _IN(_field) offsetof(struct nlmsgerr, _field)
910 #define _OUT(_field) offsetof(struct snl_errmsg_data, _field)
911 static const struct snl_attr_parser nla_p_donemsg[] = {};
913 static const struct snl_field_parser nlf_p_donemsg[] = {
914 { .off_in = _IN(error), .off_out = _OUT(error), .cb = snl_field_get_uint32 },
918 SNL_DECLARE_PARSER(snl_donemsg_parser, struct nlmsgerr, nlf_p_donemsg, nla_p_donemsg);
921 snl_parse_errmsg(struct snl_state *ss, struct nlmsghdr *hdr, struct snl_errmsg_data *e)
923 if ((hdr->nlmsg_flags & NLM_F_CAPPED) != 0)
924 return (snl_parse_nlmsg(ss, hdr, &snl_errmsg_parser, e));
926 const struct snl_hdr_parser *ps = &snl_errmsg_parser;
927 struct nlmsgerr *errmsg = (struct nlmsgerr *)(hdr + 1);
928 int hdrlen = sizeof(int) + NLMSG_ALIGN(errmsg->msg.nlmsg_len);
929 struct nlattr *attr_head = (struct nlattr *)(void *)((char *)errmsg + hdrlen);
930 int attr_len = hdr->nlmsg_len - sizeof(struct nlmsghdr) - hdrlen;
932 snl_parse_fields(ss, (struct nlmsghdr *)errmsg, hdrlen, ps->fp, ps->fp_size, e);
933 return (snl_parse_attrs_raw(ss, attr_head, attr_len, ps->np, ps->np_size, e));
937 snl_read_reply_code(struct snl_state *ss, uint32_t nlmsg_seq, struct snl_errmsg_data *e)
939 struct nlmsghdr *hdr = snl_read_reply(ss, nlmsg_seq);
943 } else if (hdr->nlmsg_type == NLMSG_ERROR) {
944 if (!snl_parse_errmsg(ss, hdr, e))
946 return (e->error == 0);
952 #define _OUT(_field) offsetof(struct snl_msg_info, _field)
953 static const struct snl_attr_parser _nla_p_cinfo[] = {
954 { .type = NLMSGINFO_ATTR_PROCESS_ID, .off = _OUT(process_id), .cb = snl_attr_get_uint32 },
955 { .type = NLMSGINFO_ATTR_PORT_ID, .off = _OUT(port_id), .cb = snl_attr_get_uint32 },
956 { .type = NLMSGINFO_ATTR_SEQ_ID, .off = _OUT(seq_id), .cb = snl_attr_get_uint32 },
959 SNL_DECLARE_ATTR_PARSER(snl_msg_info_parser, _nla_p_cinfo);
962 parse_cmsg(struct snl_state *ss, const struct msghdr *msg, struct snl_msg_info *attrs)
964 for (struct cmsghdr *cmsg = CMSG_FIRSTHDR(msg); cmsg != NULL;
965 cmsg = CMSG_NXTHDR(msg, cmsg)) {
966 if (cmsg->cmsg_level != SOL_NETLINK || cmsg->cmsg_type != NETLINK_MSG_INFO)
969 void *data = CMSG_DATA(cmsg);
970 int len = cmsg->cmsg_len - ((char *)data - (char *)cmsg);
971 const struct snl_hdr_parser *ps = &snl_msg_info_parser;
973 return (snl_parse_attrs_raw(ss, data, len, ps->np, ps->np_size, attrs));
980 * Assumes e is zeroed
982 static inline struct nlmsghdr *
983 snl_read_reply_multi(struct snl_state *ss, uint32_t nlmsg_seq, struct snl_errmsg_data *e)
985 struct nlmsghdr *hdr = snl_read_reply(ss, nlmsg_seq);
989 } else if (hdr->nlmsg_type == NLMSG_ERROR) {
990 if (!snl_parse_errmsg(ss, hdr, e))
992 } else if (hdr->nlmsg_type == NLMSG_DONE) {
993 snl_parse_nlmsg(ss, hdr, &snl_donemsg_parser, e);
1006 struct nlmsghdr *hdr;
1007 struct snl_state *ss;
1012 snl_init_writer(struct snl_state *ss, struct snl_writer *nw)
1014 nw->size = SNL_WRITER_BUFFER_SIZE;
1015 nw->base = snl_allocz(ss, nw->size);
1016 if (nw->base == NULL) {
1028 snl_realloc_msg_buffer(struct snl_writer *nw, size_t sz)
1030 uint32_t new_size = nw->size * 2;
1032 while (new_size < nw->size + sz)
1038 void *new_base = snl_allocz(nw->ss, new_size);
1039 if (new_base == NULL) {
1044 memcpy(new_base, nw->base, nw->offset);
1045 if (nw->hdr != NULL) {
1046 int hdr_off = (char *)(nw->hdr) - nw->base;
1048 nw->hdr = (struct nlmsghdr *)(void *)((char *)new_base + hdr_off);
1050 nw->base = new_base;
1055 static inline void *
1056 snl_reserve_msg_data_raw(struct snl_writer *nw, size_t sz)
1058 sz = NETLINK_ALIGN(sz);
1060 if (__predict_false(nw->offset + sz > nw->size)) {
1061 if (!snl_realloc_msg_buffer(nw, sz))
1065 void *data_ptr = &nw->base[nw->offset];
1070 #define snl_reserve_msg_object(_ns, _t) ((_t *)snl_reserve_msg_data_raw(_ns, sizeof(_t)))
1071 #define snl_reserve_msg_data(_ns, _sz, _t) ((_t *)snl_reserve_msg_data_raw(_ns, _sz))
1073 static inline void *
1074 _snl_reserve_msg_attr(struct snl_writer *nw, uint16_t nla_type, uint16_t sz)
1076 sz += sizeof(struct nlattr);
1078 struct nlattr *nla = snl_reserve_msg_data(nw, sz, struct nlattr);
1079 if (__predict_false(nla == NULL))
1081 nla->nla_type = nla_type;
1084 return ((void *)(nla + 1));
1086 #define snl_reserve_msg_attr(_ns, _at, _t) ((_t *)_snl_reserve_msg_attr(_ns, _at, sizeof(_t)))
1089 snl_add_msg_attr(struct snl_writer *nw, int attr_type, int attr_len, const void *data)
1091 int required_len = NLA_ALIGN(attr_len + sizeof(struct nlattr));
1093 if (__predict_false(nw->offset + required_len > nw->size)) {
1094 if (!snl_realloc_msg_buffer(nw, required_len))
1098 struct nlattr *nla = (struct nlattr *)(void *)(&nw->base[nw->offset]);
1100 nla->nla_len = attr_len + sizeof(struct nlattr);
1101 nla->nla_type = attr_type;
1103 if ((attr_len % 4) != 0) {
1104 /* clear padding bytes */
1105 bzero((char *)nla + required_len - 4, 4);
1107 memcpy((nla + 1), data, attr_len);
1109 nw->offset += required_len;
1114 snl_add_msg_attr_raw(struct snl_writer *nw, const struct nlattr *nla_src)
1116 int attr_len = nla_src->nla_len - sizeof(struct nlattr);
1118 assert(attr_len >= 0);
1120 return (snl_add_msg_attr(nw, nla_src->nla_type, attr_len, (const void *)(nla_src + 1)));
1124 snl_add_msg_attr_u8(struct snl_writer *nw, int attrtype, uint8_t value)
1126 return (snl_add_msg_attr(nw, attrtype, sizeof(uint8_t), &value));
1130 snl_add_msg_attr_u16(struct snl_writer *nw, int attrtype, uint16_t value)
1132 return (snl_add_msg_attr(nw, attrtype, sizeof(uint16_t), &value));
1136 snl_add_msg_attr_u32(struct snl_writer *nw, int attrtype, uint32_t value)
1138 return (snl_add_msg_attr(nw, attrtype, sizeof(uint32_t), &value));
1142 snl_add_msg_attr_u64(struct snl_writer *nw, int attrtype, uint64_t value)
1144 return (snl_add_msg_attr(nw, attrtype, sizeof(uint64_t), &value));
1148 snl_add_msg_attr_s8(struct snl_writer *nw, int attrtype, int8_t value)
1150 return (snl_add_msg_attr(nw, attrtype, sizeof(int8_t), &value));
1154 snl_add_msg_attr_s16(struct snl_writer *nw, int attrtype, int16_t value)
1156 return (snl_add_msg_attr(nw, attrtype, sizeof(int16_t), &value));
1160 snl_add_msg_attr_s32(struct snl_writer *nw, int attrtype, int32_t value)
1162 return (snl_add_msg_attr(nw, attrtype, sizeof(int32_t), &value));
1166 snl_add_msg_attr_s64(struct snl_writer *nw, int attrtype, int64_t value)
1168 return (snl_add_msg_attr(nw, attrtype, sizeof(int64_t), &value));
1172 snl_add_msg_attr_flag(struct snl_writer *nw, int attrtype)
1174 return (snl_add_msg_attr(nw, attrtype, 0, NULL));
1178 snl_add_msg_attr_string(struct snl_writer *nw, int attrtype, const char *str)
1180 return (snl_add_msg_attr(nw, attrtype, strlen(str) + 1, str));
1185 snl_get_msg_offset(const struct snl_writer *nw)
1187 return (nw->offset - ((char *)nw->hdr - nw->base));
1190 static inline void *
1191 _snl_restore_msg_offset(const struct snl_writer *nw, int off)
1193 return ((void *)((char *)nw->hdr + off));
1195 #define snl_restore_msg_offset(_ns, _off, _t) ((_t *)_snl_restore_msg_offset(_ns, _off))
1198 snl_add_msg_attr_nested(struct snl_writer *nw, int attrtype)
1200 int off = snl_get_msg_offset(nw);
1201 struct nlattr *nla = snl_reserve_msg_data(nw, sizeof(struct nlattr), struct nlattr);
1202 if (__predict_false(nla == NULL))
1204 nla->nla_type = attrtype;
1209 snl_end_attr_nested(const struct snl_writer *nw, int off)
1212 struct nlattr *nla = snl_restore_msg_offset(nw, off, struct nlattr);
1213 nla->nla_len = NETLINK_ALIGN(snl_get_msg_offset(nw) - off);
1217 static inline struct nlmsghdr *
1218 snl_create_msg_request(struct snl_writer *nw, int nlmsg_type)
1220 assert(nw->hdr == NULL);
1222 struct nlmsghdr *hdr = snl_reserve_msg_object(nw, struct nlmsghdr);
1223 hdr->nlmsg_type = nlmsg_type;
1224 hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
1231 snl_abort_msg(struct snl_writer *nw)
1233 if (nw->hdr != NULL) {
1234 int offset = (char *)(&nw->base[nw->offset]) - (char *)(nw->hdr);
1236 nw->offset -= offset;
1241 static inline struct nlmsghdr *
1242 snl_finalize_msg(struct snl_writer *nw)
1246 if (nw->hdr != NULL) {
1247 struct nlmsghdr *hdr = nw->hdr;
1249 int offset = (char *)(&nw->base[nw->offset]) - (char *)(nw->hdr);
1250 hdr->nlmsg_len = offset;
1251 hdr->nlmsg_seq = snl_get_seq(nw->ss);
1260 snl_send_msgs(struct snl_writer *nw)
1262 int offset = nw->offset;
1264 assert(nw->hdr == NULL);
1267 return (snl_send(nw->ss, nw->base, offset));
1270 static const struct snl_hdr_parser *snl_all_core_parsers[] = {
1271 &snl_errmsg_parser, &snl_donemsg_parser,
1272 &_nla_bit_parser, &_nla_bitset_parser,