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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-18 17:35:05 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-18 17:39:31 +0000 |
commit | 85c675d0d09a45a135bddd15d7b385f8758c32fb (patch) | |
tree | 76267dbc9b9a130337be3640948fe397b04ac629 /tools/testing/selftests/bpf/netlink_helpers.c | |
parent | Adding upstream version 6.6.15. (diff) | |
download | linux-85c675d0d09a45a135bddd15d7b385f8758c32fb.tar.xz linux-85c675d0d09a45a135bddd15d7b385f8758c32fb.zip |
Adding upstream version 6.7.7.upstream/6.7.7
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/bpf/netlink_helpers.c')
-rw-r--r-- | tools/testing/selftests/bpf/netlink_helpers.c | 358 |
1 files changed, 358 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/netlink_helpers.c b/tools/testing/selftests/bpf/netlink_helpers.c new file mode 100644 index 0000000000..caf36eb1d0 --- /dev/null +++ b/tools/testing/selftests/bpf/netlink_helpers.c @@ -0,0 +1,358 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Taken & modified from iproute2's libnetlink.c + * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> + */ +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <errno.h> +#include <time.h> +#include <sys/socket.h> + +#include "netlink_helpers.h" + +static int rcvbuf = 1024 * 1024; + +void rtnl_close(struct rtnl_handle *rth) +{ + if (rth->fd >= 0) { + close(rth->fd); + rth->fd = -1; + } +} + +int rtnl_open_byproto(struct rtnl_handle *rth, unsigned int subscriptions, + int protocol) +{ + socklen_t addr_len; + int sndbuf = 32768; + int one = 1; + + memset(rth, 0, sizeof(*rth)); + rth->proto = protocol; + rth->fd = socket(AF_NETLINK, SOCK_RAW | SOCK_CLOEXEC, protocol); + if (rth->fd < 0) { + perror("Cannot open netlink socket"); + return -1; + } + if (setsockopt(rth->fd, SOL_SOCKET, SO_SNDBUF, + &sndbuf, sizeof(sndbuf)) < 0) { + perror("SO_SNDBUF"); + goto err; + } + if (setsockopt(rth->fd, SOL_SOCKET, SO_RCVBUF, + &rcvbuf, sizeof(rcvbuf)) < 0) { + perror("SO_RCVBUF"); + goto err; + } + + /* Older kernels may no support extended ACK reporting */ + setsockopt(rth->fd, SOL_NETLINK, NETLINK_EXT_ACK, + &one, sizeof(one)); + + memset(&rth->local, 0, sizeof(rth->local)); + rth->local.nl_family = AF_NETLINK; + rth->local.nl_groups = subscriptions; + + if (bind(rth->fd, (struct sockaddr *)&rth->local, + sizeof(rth->local)) < 0) { + perror("Cannot bind netlink socket"); + goto err; + } + addr_len = sizeof(rth->local); + if (getsockname(rth->fd, (struct sockaddr *)&rth->local, + &addr_len) < 0) { + perror("Cannot getsockname"); + goto err; + } + if (addr_len != sizeof(rth->local)) { + fprintf(stderr, "Wrong address length %d\n", addr_len); + goto err; + } + if (rth->local.nl_family != AF_NETLINK) { + fprintf(stderr, "Wrong address family %d\n", + rth->local.nl_family); + goto err; + } + rth->seq = time(NULL); + return 0; +err: + rtnl_close(rth); + return -1; +} + +int rtnl_open(struct rtnl_handle *rth, unsigned int subscriptions) +{ + return rtnl_open_byproto(rth, subscriptions, NETLINK_ROUTE); +} + +static int __rtnl_recvmsg(int fd, struct msghdr *msg, int flags) +{ + int len; + + do { + len = recvmsg(fd, msg, flags); + } while (len < 0 && (errno == EINTR || errno == EAGAIN)); + if (len < 0) { + fprintf(stderr, "netlink receive error %s (%d)\n", + strerror(errno), errno); + return -errno; + } + if (len == 0) { + fprintf(stderr, "EOF on netlink\n"); + return -ENODATA; + } + return len; +} + +static int rtnl_recvmsg(int fd, struct msghdr *msg, char **answer) +{ + struct iovec *iov = msg->msg_iov; + char *buf; + int len; + + iov->iov_base = NULL; + iov->iov_len = 0; + + len = __rtnl_recvmsg(fd, msg, MSG_PEEK | MSG_TRUNC); + if (len < 0) + return len; + if (len < 32768) + len = 32768; + buf = malloc(len); + if (!buf) { + fprintf(stderr, "malloc error: not enough buffer\n"); + return -ENOMEM; + } + iov->iov_base = buf; + iov->iov_len = len; + len = __rtnl_recvmsg(fd, msg, 0); + if (len < 0) { + free(buf); + return len; + } + if (answer) + *answer = buf; + else + free(buf); + return len; +} + +static void rtnl_talk_error(struct nlmsghdr *h, struct nlmsgerr *err, + nl_ext_ack_fn_t errfn) +{ + fprintf(stderr, "RTNETLINK answers: %s\n", + strerror(-err->error)); +} + +static int __rtnl_talk_iov(struct rtnl_handle *rtnl, struct iovec *iov, + size_t iovlen, struct nlmsghdr **answer, + bool show_rtnl_err, nl_ext_ack_fn_t errfn) +{ + struct sockaddr_nl nladdr = { .nl_family = AF_NETLINK }; + struct iovec riov; + struct msghdr msg = { + .msg_name = &nladdr, + .msg_namelen = sizeof(nladdr), + .msg_iov = iov, + .msg_iovlen = iovlen, + }; + unsigned int seq = 0; + struct nlmsghdr *h; + int i, status; + char *buf; + + for (i = 0; i < iovlen; i++) { + h = iov[i].iov_base; + h->nlmsg_seq = seq = ++rtnl->seq; + if (answer == NULL) + h->nlmsg_flags |= NLM_F_ACK; + } + status = sendmsg(rtnl->fd, &msg, 0); + if (status < 0) { + perror("Cannot talk to rtnetlink"); + return -1; + } + /* change msg to use the response iov */ + msg.msg_iov = &riov; + msg.msg_iovlen = 1; + i = 0; + while (1) { +next: + status = rtnl_recvmsg(rtnl->fd, &msg, &buf); + ++i; + if (status < 0) + return status; + if (msg.msg_namelen != sizeof(nladdr)) { + fprintf(stderr, + "Sender address length == %d!\n", + msg.msg_namelen); + exit(1); + } + for (h = (struct nlmsghdr *)buf; status >= sizeof(*h); ) { + int len = h->nlmsg_len; + int l = len - sizeof(*h); + + if (l < 0 || len > status) { + if (msg.msg_flags & MSG_TRUNC) { + fprintf(stderr, "Truncated message!\n"); + free(buf); + return -1; + } + fprintf(stderr, + "Malformed message: len=%d!\n", + len); + exit(1); + } + if (nladdr.nl_pid != 0 || + h->nlmsg_pid != rtnl->local.nl_pid || + h->nlmsg_seq > seq || h->nlmsg_seq < seq - iovlen) { + /* Don't forget to skip that message. */ + status -= NLMSG_ALIGN(len); + h = (struct nlmsghdr *)((char *)h + NLMSG_ALIGN(len)); + continue; + } + if (h->nlmsg_type == NLMSG_ERROR) { + struct nlmsgerr *err = (struct nlmsgerr *)NLMSG_DATA(h); + int error = err->error; + + if (l < sizeof(struct nlmsgerr)) { + fprintf(stderr, "ERROR truncated\n"); + free(buf); + return -1; + } + if (error) { + errno = -error; + if (rtnl->proto != NETLINK_SOCK_DIAG && + show_rtnl_err) + rtnl_talk_error(h, err, errfn); + } + if (i < iovlen) { + free(buf); + goto next; + } + if (error) { + free(buf); + return -i; + } + if (answer) + *answer = (struct nlmsghdr *)buf; + else + free(buf); + return 0; + } + if (answer) { + *answer = (struct nlmsghdr *)buf; + return 0; + } + fprintf(stderr, "Unexpected reply!\n"); + status -= NLMSG_ALIGN(len); + h = (struct nlmsghdr *)((char *)h + NLMSG_ALIGN(len)); + } + free(buf); + if (msg.msg_flags & MSG_TRUNC) { + fprintf(stderr, "Message truncated!\n"); + continue; + } + if (status) { + fprintf(stderr, "Remnant of size %d!\n", status); + exit(1); + } + } +} + +static int __rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n, + struct nlmsghdr **answer, bool show_rtnl_err, + nl_ext_ack_fn_t errfn) +{ + struct iovec iov = { + .iov_base = n, + .iov_len = n->nlmsg_len, + }; + + return __rtnl_talk_iov(rtnl, &iov, 1, answer, show_rtnl_err, errfn); +} + +int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n, + struct nlmsghdr **answer) +{ + return __rtnl_talk(rtnl, n, answer, true, NULL); +} + +int addattr(struct nlmsghdr *n, int maxlen, int type) +{ + return addattr_l(n, maxlen, type, NULL, 0); +} + +int addattr8(struct nlmsghdr *n, int maxlen, int type, __u8 data) +{ + return addattr_l(n, maxlen, type, &data, sizeof(__u8)); +} + +int addattr16(struct nlmsghdr *n, int maxlen, int type, __u16 data) +{ + return addattr_l(n, maxlen, type, &data, sizeof(__u16)); +} + +int addattr32(struct nlmsghdr *n, int maxlen, int type, __u32 data) +{ + return addattr_l(n, maxlen, type, &data, sizeof(__u32)); +} + +int addattr64(struct nlmsghdr *n, int maxlen, int type, __u64 data) +{ + return addattr_l(n, maxlen, type, &data, sizeof(__u64)); +} + +int addattrstrz(struct nlmsghdr *n, int maxlen, int type, const char *str) +{ + return addattr_l(n, maxlen, type, str, strlen(str)+1); +} + +int addattr_l(struct nlmsghdr *n, int maxlen, int type, const void *data, + int alen) +{ + int len = RTA_LENGTH(alen); + struct rtattr *rta; + + if (NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len) > maxlen) { + fprintf(stderr, "%s: Message exceeded bound of %d\n", + __func__, maxlen); + return -1; + } + rta = NLMSG_TAIL(n); + rta->rta_type = type; + rta->rta_len = len; + if (alen) + memcpy(RTA_DATA(rta), data, alen); + n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len); + return 0; +} + +int addraw_l(struct nlmsghdr *n, int maxlen, const void *data, int len) +{ + if (NLMSG_ALIGN(n->nlmsg_len) + NLMSG_ALIGN(len) > maxlen) { + fprintf(stderr, "%s: Message exceeded bound of %d\n", + __func__, maxlen); + return -1; + } + + memcpy(NLMSG_TAIL(n), data, len); + memset((void *) NLMSG_TAIL(n) + len, 0, NLMSG_ALIGN(len) - len); + n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + NLMSG_ALIGN(len); + return 0; +} + +struct rtattr *addattr_nest(struct nlmsghdr *n, int maxlen, int type) +{ + struct rtattr *nest = NLMSG_TAIL(n); + + addattr_l(n, maxlen, type, NULL, 0); + return nest; +} + +int addattr_nest_end(struct nlmsghdr *n, struct rtattr *nest) +{ + nest->rta_len = (void *)NLMSG_TAIL(n) - (void *)nest; + return n->nlmsg_len; +} |