diff options
Diffstat (limited to 'networking/libiproute/libnetlink.c')
-rw-r--r-- | networking/libiproute/libnetlink.c | 409 |
1 files changed, 409 insertions, 0 deletions
diff --git a/networking/libiproute/libnetlink.c b/networking/libiproute/libnetlink.c new file mode 100644 index 0000000..01454fb --- /dev/null +++ b/networking/libiproute/libnetlink.c @@ -0,0 +1,409 @@ +/* vi: set sw=4 ts=4: */ +/* + * libnetlink.c RTnetlink service routines. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> + * + */ + +#include <sys/socket.h> +#include <sys/uio.h> + +#include "libbb.h" +#include "libnetlink.h" + +void FAST_FUNC rtnl_close(struct rtnl_handle *rth) +{ + close(rth->fd); +} + +int FAST_FUNC xrtnl_open(struct rtnl_handle *rth/*, unsigned subscriptions*/) +{ + socklen_t addr_len; + + memset(rth, 0, sizeof(rth)); + + rth->fd = xsocket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); + + memset(&rth->local, 0, sizeof(rth->local)); + rth->local.nl_family = AF_NETLINK; + /*rth->local.nl_groups = subscriptions;*/ + + xbind(rth->fd, (struct sockaddr*)&rth->local, sizeof(rth->local)); + addr_len = sizeof(rth->local); + if (getsockname(rth->fd, (struct sockaddr*)&rth->local, &addr_len) < 0) + bb_perror_msg_and_die("getsockname"); + if (addr_len != sizeof(rth->local)) + bb_error_msg_and_die("wrong address length %d", addr_len); + if (rth->local.nl_family != AF_NETLINK) + bb_error_msg_and_die("wrong address family %d", rth->local.nl_family); + rth->seq = time(NULL); + return 0; +} + +int FAST_FUNC xrtnl_wilddump_request(struct rtnl_handle *rth, int family, int type) +{ + struct { + struct nlmsghdr nlh; + struct rtgenmsg g; + } req; + struct sockaddr_nl nladdr; + + memset(&nladdr, 0, sizeof(nladdr)); + nladdr.nl_family = AF_NETLINK; + + req.nlh.nlmsg_len = sizeof(req); + req.nlh.nlmsg_type = type; + req.nlh.nlmsg_flags = NLM_F_ROOT|NLM_F_MATCH|NLM_F_REQUEST; + req.nlh.nlmsg_pid = 0; + req.nlh.nlmsg_seq = rth->dump = ++rth->seq; + req.g.rtgen_family = family; + + return xsendto(rth->fd, (void*)&req, sizeof(req), + (struct sockaddr*)&nladdr, sizeof(nladdr)); +} + +int FAST_FUNC rtnl_send(struct rtnl_handle *rth, char *buf, int len) +{ + struct sockaddr_nl nladdr; + + memset(&nladdr, 0, sizeof(nladdr)); + nladdr.nl_family = AF_NETLINK; + + return xsendto(rth->fd, buf, len, (struct sockaddr*)&nladdr, sizeof(nladdr)); +} + +int FAST_FUNC rtnl_dump_request(struct rtnl_handle *rth, int type, void *req, int len) +{ + struct nlmsghdr nlh; + struct sockaddr_nl nladdr; + struct iovec iov[2] = { { &nlh, sizeof(nlh) }, { req, len } }; + struct msghdr msg = { + (void*)&nladdr, sizeof(nladdr), + iov, 2, + NULL, 0, + 0 + }; + + memset(&nladdr, 0, sizeof(nladdr)); + nladdr.nl_family = AF_NETLINK; + + nlh.nlmsg_len = NLMSG_LENGTH(len); + nlh.nlmsg_type = type; + nlh.nlmsg_flags = NLM_F_ROOT|NLM_F_MATCH|NLM_F_REQUEST; + nlh.nlmsg_pid = 0; + nlh.nlmsg_seq = rth->dump = ++rth->seq; + + return sendmsg(rth->fd, &msg, 0); +} + +static int rtnl_dump_filter(struct rtnl_handle *rth, + int (*filter)(const struct sockaddr_nl *, struct nlmsghdr *n, void *), + void *arg1/*, + int (*junk)(struct sockaddr_nl *, struct nlmsghdr *n, void *), + void *arg2*/) +{ + int retval = -1; + char *buf = xmalloc(8*1024); /* avoid big stack buffer */ + struct sockaddr_nl nladdr; + struct iovec iov = { buf, 8*1024 }; + + while (1) { + int status; + struct nlmsghdr *h; + + struct msghdr msg = { + (void*)&nladdr, sizeof(nladdr), + &iov, 1, + NULL, 0, + 0 + }; + + status = recvmsg(rth->fd, &msg, 0); + + if (status < 0) { + if (errno == EINTR) + continue; + bb_perror_msg("OVERRUN"); + continue; + } + if (status == 0) { + bb_error_msg("EOF on netlink"); + goto ret; + } + if (msg.msg_namelen != sizeof(nladdr)) { + bb_error_msg_and_die("sender address length == %d", msg.msg_namelen); + } + + h = (struct nlmsghdr*)buf; + while (NLMSG_OK(h, status)) { + int err; + + if (nladdr.nl_pid != 0 || + h->nlmsg_pid != rth->local.nl_pid || + h->nlmsg_seq != rth->dump) { +// if (junk) { +// err = junk(&nladdr, h, arg2); +// if (err < 0) { +// retval = err; +// goto ret; +// } +// } + goto skip_it; + } + + if (h->nlmsg_type == NLMSG_DONE) { + goto ret_0; + } + if (h->nlmsg_type == NLMSG_ERROR) { + struct nlmsgerr *l_err = (struct nlmsgerr*)NLMSG_DATA(h); + if (h->nlmsg_len < NLMSG_LENGTH(sizeof(struct nlmsgerr))) { + bb_error_msg("ERROR truncated"); + } else { + errno = -l_err->error; + bb_perror_msg("RTNETLINK answers"); + } + goto ret; + } + err = filter(&nladdr, h, arg1); + if (err < 0) { + retval = err; + goto ret; + } + + skip_it: + h = NLMSG_NEXT(h, status); + } + if (msg.msg_flags & MSG_TRUNC) { + bb_error_msg("message truncated"); + continue; + } + if (status) { + bb_error_msg_and_die("remnant of size %d!", status); + } + } /* while (1) */ + ret_0: + retval++; /* = 0 */ + ret: + free(buf); + return retval; +} + +int FAST_FUNC xrtnl_dump_filter(struct rtnl_handle *rth, + int (*filter)(const struct sockaddr_nl *, struct nlmsghdr *, void *), + void *arg1) +{ + int ret = rtnl_dump_filter(rth, filter, arg1/*, NULL, NULL*/); + if (ret < 0) + bb_error_msg_and_die("dump terminated"); + return ret; +} + +int FAST_FUNC rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n, + pid_t peer, unsigned groups, + struct nlmsghdr *answer, + int (*junk)(struct sockaddr_nl *, struct nlmsghdr *, void *), + void *jarg) +{ +/* bbox doesn't use parameters no. 3, 4, 6, 7, they are stubbed out */ +#define peer 0 +#define groups 0 +#define junk NULL +#define jarg NULL + int retval = -1; + int status; + unsigned seq; + struct nlmsghdr *h; + struct sockaddr_nl nladdr; + struct iovec iov = { (void*)n, n->nlmsg_len }; + char *buf = xmalloc(8*1024); /* avoid big stack buffer */ + struct msghdr msg = { + (void*)&nladdr, sizeof(nladdr), + &iov, 1, + NULL, 0, + 0 + }; + + memset(&nladdr, 0, sizeof(nladdr)); + nladdr.nl_family = AF_NETLINK; +// nladdr.nl_pid = peer; +// nladdr.nl_groups = groups; + + n->nlmsg_seq = seq = ++rtnl->seq; + if (answer == NULL) { + n->nlmsg_flags |= NLM_F_ACK; + } + status = sendmsg(rtnl->fd, &msg, 0); + + if (status < 0) { + bb_perror_msg("cannot talk to rtnetlink"); + goto ret; + } + + iov.iov_base = buf; + + while (1) { + iov.iov_len = 8*1024; + status = recvmsg(rtnl->fd, &msg, 0); + + if (status < 0) { + if (errno == EINTR) { + continue; + } + bb_perror_msg("OVERRUN"); + continue; + } + if (status == 0) { + bb_error_msg("EOF on netlink"); + goto ret; + } + if (msg.msg_namelen != sizeof(nladdr)) { + bb_error_msg_and_die("sender address length == %d", msg.msg_namelen); + } + for (h = (struct nlmsghdr*)buf; status >= (int)sizeof(*h); ) { +// int l_err; + int len = h->nlmsg_len; + int l = len - sizeof(*h); + + if (l < 0 || len > status) { + if (msg.msg_flags & MSG_TRUNC) { + bb_error_msg("truncated message"); + goto ret; + } + bb_error_msg_and_die("malformed message: len=%d!", len); + } + + if (nladdr.nl_pid != peer || + h->nlmsg_pid != rtnl->local.nl_pid || + h->nlmsg_seq != seq) { +// if (junk) { +// l_err = junk(&nladdr, h, jarg); +// if (l_err < 0) { +// retval = l_err; +// goto ret; +// } +// } + continue; + } + + if (h->nlmsg_type == NLMSG_ERROR) { + struct nlmsgerr *err = (struct nlmsgerr*)NLMSG_DATA(h); + if (l < (int)sizeof(struct nlmsgerr)) { + bb_error_msg("ERROR truncated"); + } else { + errno = - err->error; + if (errno == 0) { + if (answer) { + memcpy(answer, h, h->nlmsg_len); + } + goto ret_0; + } + bb_perror_msg("RTNETLINK answers"); + } + goto ret; + } + if (answer) { + memcpy(answer, h, h->nlmsg_len); + goto ret_0; + } + + bb_error_msg("unexpected reply!"); + + status -= NLMSG_ALIGN(len); + h = (struct nlmsghdr*)((char*)h + NLMSG_ALIGN(len)); + } + if (msg.msg_flags & MSG_TRUNC) { + bb_error_msg("message truncated"); + continue; + } + if (status) { + bb_error_msg_and_die("remnant of size %d!", status); + } + } /* while (1) */ + ret_0: + retval++; /* = 0 */ + ret: + free(buf); + return retval; +} + +int FAST_FUNC addattr32(struct nlmsghdr *n, int maxlen, int type, uint32_t data) +{ + int len = RTA_LENGTH(4); + struct rtattr *rta; + if ((int)(NLMSG_ALIGN(n->nlmsg_len) + len) > maxlen) + return -1; + rta = (struct rtattr*)(((char*)n) + NLMSG_ALIGN(n->nlmsg_len)); + rta->rta_type = type; + rta->rta_len = len; + memcpy(RTA_DATA(rta), &data, 4); + n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + len; + return 0; +} + +int FAST_FUNC addattr_l(struct nlmsghdr *n, int maxlen, int type, void *data, int alen) +{ + int len = RTA_LENGTH(alen); + struct rtattr *rta; + + if ((int)(NLMSG_ALIGN(n->nlmsg_len) + len) > maxlen) + return -1; + rta = (struct rtattr*)(((char*)n) + NLMSG_ALIGN(n->nlmsg_len)); + rta->rta_type = type; + rta->rta_len = len; + memcpy(RTA_DATA(rta), data, alen); + n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + len; + return 0; +} + +int FAST_FUNC rta_addattr32(struct rtattr *rta, int maxlen, int type, uint32_t data) +{ + int len = RTA_LENGTH(4); + struct rtattr *subrta; + + if (RTA_ALIGN(rta->rta_len) + len > maxlen) { + return -1; + } + subrta = (struct rtattr*)(((char*)rta) + RTA_ALIGN(rta->rta_len)); + subrta->rta_type = type; + subrta->rta_len = len; + memcpy(RTA_DATA(subrta), &data, 4); + rta->rta_len = NLMSG_ALIGN(rta->rta_len) + len; + return 0; +} + +int FAST_FUNC rta_addattr_l(struct rtattr *rta, int maxlen, int type, void *data, int alen) +{ + struct rtattr *subrta; + int len = RTA_LENGTH(alen); + + if (RTA_ALIGN(rta->rta_len) + len > maxlen) { + return -1; + } + subrta = (struct rtattr*)(((char*)rta) + RTA_ALIGN(rta->rta_len)); + subrta->rta_type = type; + subrta->rta_len = len; + memcpy(RTA_DATA(subrta), data, alen); + rta->rta_len = NLMSG_ALIGN(rta->rta_len) + len; + return 0; +} + + +int FAST_FUNC parse_rtattr(struct rtattr *tb[], int max, struct rtattr *rta, int len) +{ + while (RTA_OK(rta, len)) { + if (rta->rta_type <= max) { + tb[rta->rta_type] = rta; + } + rta = RTA_NEXT(rta,len); + } + if (len) { + bb_error_msg("deficit %d, rta_len=%d!", len, rta->rta_len); + } + return 0; +} |