diff options
Diffstat (limited to 'sys/netlink/netlink_message_parser.c')
-rw-r--r-- | sys/netlink/netlink_message_parser.c | 472 |
1 files changed, 472 insertions, 0 deletions
diff --git a/sys/netlink/netlink_message_parser.c b/sys/netlink/netlink_message_parser.c new file mode 100644 index 000000000000..d33eddb800e4 --- /dev/null +++ b/sys/netlink/netlink_message_parser.c @@ -0,0 +1,472 @@ +/*- + * SPDX-License-Identifier: BSD-2-Clause-FreeBSD + * + * Copyright (c) 2022 Alexander V. Chernikov <melifaro@FreeBSD.org> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); +#include "opt_inet.h" +#include "opt_inet6.h" +#include <sys/types.h> +#include <sys/malloc.h> +#include <sys/rmlock.h> +#include <sys/socket.h> + +#include <machine/stdarg.h> + +#include <net/if.h> +#include <net/route.h> +#include <net/route/nhop.h> + +#include <net/route/route_ctl.h> +#include <netlink/netlink.h> +#include <netlink/netlink_ctl.h> +#include <netlink/netlink_var.h> +#include <netlink/netlink_route.h> + +#define DEBUG_MOD_NAME nl_parser +#define DEBUG_MAX_LEVEL LOG_DEBUG3 +#include <netlink/netlink_debug.h> +_DECLARE_DEBUG(LOG_DEBUG); + +bool +nlmsg_report_err_msg(struct nl_pstate *npt, const char *fmt, ...) +{ + va_list ap; + + if (npt->err_msg != NULL) + return (false); + char *buf = npt_alloc(npt, NL_MAX_ERROR_BUF); + if (buf == NULL) + return (false); + va_start(ap, fmt); + vsnprintf(buf, NL_MAX_ERROR_BUF, fmt, ap); + va_end(ap); + + npt->err_msg = buf; + return (true); +} + +bool +nlmsg_report_err_offset(struct nl_pstate *npt, uint32_t off) +{ + if (npt->err_off != 0) + return (false); + npt->err_off = off; + return (true); +} + +static const struct nlattr_parser * +search_states(const struct nlattr_parser *ps, int pslen, int key) +{ + int left_i = 0, right_i = pslen - 1; + + if (key < ps[0].type || key > ps[pslen - 1].type) + return (NULL); + + while (left_i + 1 < right_i) { + int mid_i = (left_i + right_i) / 2; + if (key < ps[mid_i].type) + right_i = mid_i; + else if (key > ps[mid_i].type) + left_i = mid_i + 1; + else + return (&ps[mid_i]); + } + if (ps[left_i].type == key) + return (&ps[left_i]); + else if (ps[right_i].type == key) + return (&ps[right_i]); + return (NULL); +} + +int +nl_parse_attrs_raw(struct nlattr *nla_head, int len, const struct nlattr_parser *ps, int pslen, + struct nl_pstate *npt, void *target) +{ + struct nlattr *nla = NULL; + int error = 0; + + NL_LOG(LOG_DEBUG3, "parse %p remaining_len %d", nla_head, len); + int orig_len = len; + NLA_FOREACH(nla, nla_head, len) { + NL_LOG(LOG_DEBUG3, ">> parsing %p attr_type %d len %d (rem %d)", nla, nla->nla_type, nla->nla_len, len); + if (nla->nla_len < sizeof(struct nlattr)) { + NLMSG_REPORT_ERR_MSG(npt, "Invalid attr %p type %d len: %d", + nla, nla->nla_type, nla->nla_len); + uint32_t off = (char *)nla - (char *)npt->hdr; + nlmsg_report_err_offset(npt, off); + return (EINVAL); + } + + int nla_type = nla->nla_type & NLA_TYPE_MASK; + const struct nlattr_parser *s = search_states(ps, pslen, nla_type); + if (s != NULL) { + void *ptr = (void *)((char *)target + s->off); + error = s->cb(nla, npt, s->arg, ptr); + if (error != 0) { + uint32_t off = (char *)nla - (char *)npt->hdr; + nlmsg_report_err_offset(npt, off); + NL_LOG(LOG_DEBUG3, "parse failed att offset %u", off); + return (error); + } + } else { + /* Ignore non-specified attributes */ + NL_LOG(LOG_DEBUG3, "ignoring attr %d", nla->nla_type); + } + } + if (len >= sizeof(struct nlattr)) { + nla = (struct nlattr *)((char *)nla_head + (orig_len - len)); + NL_LOG(LOG_DEBUG3, " >>> end %p attr_type %d len %d", nla, + nla->nla_type, nla->nla_len); + } + NL_LOG(LOG_DEBUG3, "end parse: %p remaining_len %d", nla, len); + + return (0); +} + +int +nl_parse_attrs(struct nlmsghdr *hdr, int hdrlen, struct nlattr_parser *ps, int pslen, + struct nl_pstate *npt, void *target) +{ + int off = NLMSG_HDRLEN + NETLINK_ALIGN(hdrlen); + int len = hdr->nlmsg_len - off; + struct nlattr *nla_head = (struct nlattr *)((char *)hdr + off); + + return (nl_parse_attrs_raw(nla_head, len, ps, pslen, npt, target)); +} + +int +nlattr_get_flag(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) +{ + if (__predict_false(NLA_DATA_LEN(nla) != 0)) { + NLMSG_REPORT_ERR_MSG(npt, "nla type %d size(%u) is not a flag", + nla->nla_type, NLA_DATA_LEN(nla)); + return (EINVAL); + } + + *((uint8_t *)target) = 1; + return (0); +} + +static struct sockaddr * +parse_rta_ip4(void *rta_data, struct nl_pstate *npt, int *perror) +{ + struct sockaddr_in *sin; + + sin = (struct sockaddr_in *)npt_alloc_sockaddr(npt, sizeof(struct sockaddr_in)); + if (__predict_false(sin == NULL)) { + *perror = ENOBUFS; + return (NULL); + } + sin->sin_len = sizeof(struct sockaddr_in); + sin->sin_family = AF_INET; + memcpy(&sin->sin_addr, rta_data, sizeof(struct in_addr)); + return ((struct sockaddr *)sin); +} + +static struct sockaddr * +parse_rta_ip6(void *rta_data, struct nl_pstate *npt, int *perror) +{ + struct sockaddr_in6 *sin6; + + sin6 = (struct sockaddr_in6 *)npt_alloc_sockaddr(npt, sizeof(struct sockaddr_in6)); + if (__predict_false(sin6 == NULL)) { + *perror = ENOBUFS; + return (NULL); + } + sin6->sin6_len = sizeof(struct sockaddr_in6); + sin6->sin6_family = AF_INET6; + memcpy(&sin6->sin6_addr, rta_data, sizeof(struct in6_addr)); + return ((struct sockaddr *)sin6); +} + +static struct sockaddr * +parse_rta_ip(struct rtattr *rta, struct nl_pstate *npt, int *perror) +{ + void *rta_data = NL_RTA_DATA(rta); + int rta_len = NL_RTA_DATA_LEN(rta); + + if (rta_len == sizeof(struct in_addr)) { + return (parse_rta_ip4(rta_data, npt, perror)); + } else if (rta_len == sizeof(struct in6_addr)) { + return (parse_rta_ip6(rta_data, npt, perror)); + } else { + NLMSG_REPORT_ERR_MSG(npt, "unknown IP len: %d for rta type %d", + rta_len, rta->rta_type); + *perror = ENOTSUP; + return (NULL); + } + return (NULL); +} + +int +nlattr_get_ip(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) +{ + int error = 0; + + struct sockaddr *sa = parse_rta_ip((struct rtattr *)nla, npt, &error); + + *((struct sockaddr **)target) = sa; + return (error); +} + +static struct sockaddr * +parse_rta_via(struct rtattr *rta, struct nl_pstate *npt, int *perror) +{ + struct rtvia *via = NL_RTA_DATA(rta); + int data_len = NL_RTA_DATA_LEN(rta); + + if (__predict_false(data_len) < sizeof(struct rtvia)) { + NLMSG_REPORT_ERR_MSG(npt, "undersized RTA_VIA(%d) attr: len %d", + rta->rta_type, data_len); + *perror = EINVAL; + return (NULL); + } + data_len -= offsetof(struct rtvia, rtvia_addr); + + switch (via->rtvia_family) { + case AF_INET: + if (__predict_false(data_len < sizeof(struct in_addr))) { + *perror = EINVAL; + return (NULL); + } + return (parse_rta_ip4(via->rtvia_addr, npt, perror)); + case AF_INET6: + if (__predict_false(data_len < sizeof(struct in6_addr))) { + *perror = EINVAL; + return (NULL); + } + return (parse_rta_ip6(via->rtvia_addr, npt, perror)); + default: + *perror = ENOTSUP; + return (NULL); + } +} + +int +nlattr_get_ipvia(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) +{ + int error = 0; + + struct sockaddr *sa = parse_rta_via((struct rtattr *)nla, npt, &error); + + *((struct sockaddr **)target) = sa; + return (error); +} + + +int +nlattr_get_uint16(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) +{ + if (__predict_false(NLA_DATA_LEN(nla) != sizeof(uint16_t))) { + NLMSG_REPORT_ERR_MSG(npt, "nla type %d size(%u) is not uint32", + nla->nla_type, NLA_DATA_LEN(nla)); + return (EINVAL); + } + *((uint16_t *)target) = *((const uint16_t *)NL_RTA_DATA_CONST(nla)); + return (0); +} + +int +nlattr_get_uint32(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) +{ + if (__predict_false(NLA_DATA_LEN(nla) != sizeof(uint32_t))) { + NLMSG_REPORT_ERR_MSG(npt, "nla type %d size(%u) is not uint32", + nla->nla_type, NLA_DATA_LEN(nla)); + return (EINVAL); + } + *((uint32_t *)target) = *((const uint32_t *)NL_RTA_DATA_CONST(nla)); + return (0); +} + +int +nlattr_get_uint64(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) +{ + if (__predict_false(NLA_DATA_LEN(nla) != sizeof(uint64_t))) { + NLMSG_REPORT_ERR_MSG(npt, "nla type %d size(%u) is not uint64", + nla->nla_type, NLA_DATA_LEN(nla)); + return (EINVAL); + } + memcpy(target, NL_RTA_DATA_CONST(nla), sizeof(uint64_t)); + return (0); +} + +static int +nlattr_get_ifp_internal(struct nlattr *nla, struct nl_pstate *npt, + void *target, bool zero_ok) +{ + if (__predict_false(NLA_DATA_LEN(nla) != sizeof(uint32_t))) { + NLMSG_REPORT_ERR_MSG(npt, "nla type %d size(%u) is not uint32", + nla->nla_type, NLA_DATA_LEN(nla)); + return (EINVAL); + } + uint32_t ifindex = *((const uint32_t *)NLA_DATA_CONST(nla)); + + if (ifindex == 0 && zero_ok) { + *((struct ifnet **)target) = NULL; + return (0); + } + + NET_EPOCH_ASSERT(); + + struct ifnet *ifp = ifnet_byindex(ifindex); + if (__predict_false(ifp == NULL)) { + NLMSG_REPORT_ERR_MSG(npt, "nla type %d: ifindex %u invalid", + nla->nla_type, ifindex); + return (ENOENT); + } + *((struct ifnet **)target) = ifp; + NL_LOG(LOG_DEBUG3, "nla type %d: ifindex %u -> %s", nla->nla_type, + ifindex, if_name(ifp)); + + return (0); +} + +int +nlattr_get_ifp(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) +{ + return (nlattr_get_ifp_internal(nla, npt, target, false)); +} + +int +nlattr_get_ifpz(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) +{ + return (nlattr_get_ifp_internal(nla, npt, target, true)); +} + +int +nlattr_get_string(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) +{ + int maxlen = NLA_DATA_LEN(nla); + + if (__predict_false(strnlen((char *)NLA_DATA(nla), maxlen) >= maxlen)) { + NLMSG_REPORT_ERR_MSG(npt, "nla type %d size(%u) is not NULL-terminated", + nla->nla_type, maxlen); + return (EINVAL); + } + + *((char **)target) = (char *)NLA_DATA(nla); + return (0); +} + +int +nlattr_get_stringn(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) +{ + int maxlen = NLA_DATA_LEN(nla); + + char *buf = npt_alloc(npt, maxlen + 1); + if (buf == NULL) + return (ENOMEM); + buf[maxlen] = '\0'; + memcpy(buf, NLA_DATA(nla), maxlen); + + *((char **)target) = buf; + return (0); +} +int +nlattr_get_nla(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) +{ + NL_LOG(LOG_DEBUG3, "STORING %p len %d", nla, nla->nla_len); + *((struct nlattr **)target) = nla; + return (0); +} + +int +nlattr_get_nested(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) +{ + const struct nlhdr_parser *p = (const struct nlhdr_parser *)arg; + int error; + + /* Assumes target points to the beginning of the structure */ + error = nl_parse_header(NLA_DATA(nla), NLA_DATA_LEN(nla), p, npt, target); + return (error); +} + +int +nlf_get_ifp(void *src, struct nl_pstate *npt, void *target) +{ + int ifindex = *((const int *)src); + + NET_EPOCH_ASSERT(); + + struct ifnet *ifp = ifnet_byindex(ifindex); + if (ifp == NULL) { + NL_LOG(LOG_DEBUG, "ifindex %u invalid", ifindex); + return (ENOENT); + } + *((struct ifnet **)target) = ifp; + + return (0); +} + +int +nlf_get_ifpz(void *src, struct nl_pstate *npt, void *target) +{ + int ifindex = *((const int *)src); + + NET_EPOCH_ASSERT(); + + struct ifnet *ifp = ifnet_byindex(ifindex); + if (ifindex != 0 && ifp == NULL) { + NL_LOG(LOG_DEBUG, "ifindex %u invalid", ifindex); + return (ENOENT); + } + *((struct ifnet **)target) = ifp; + + return (0); +} + +int +nlf_get_u8(void *src, struct nl_pstate *npt, void *target) +{ + uint8_t val = *((const uint8_t *)src); + + *((uint8_t *)target) = val; + + return (0); +} + +int +nlf_get_u8_u32(void *src, struct nl_pstate *npt, void *target) +{ + *((uint32_t *)target) = *((const uint8_t *)src); + return (0); +} + +int +nlf_get_u16(void *src, struct nl_pstate *npt, void *target) +{ + *((uint16_t *)target) = *((const uint16_t *)src); + return (0); +} + +int +nlf_get_u32(void *src, struct nl_pstate *npt, void *target) +{ + *((uint32_t *)target) = *((const uint32_t *)src); + return (0); +} + |