diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/check_pf.c')
| -rw-r--r-- | sysdeps/unix/sysv/linux/check_pf.c | 391 |
1 files changed, 0 insertions, 391 deletions
diff --git a/sysdeps/unix/sysv/linux/check_pf.c b/sysdeps/unix/sysv/linux/check_pf.c deleted file mode 100644 index 3bf221a177..0000000000 --- a/sysdeps/unix/sysv/linux/check_pf.c +++ /dev/null @@ -1,391 +0,0 @@ -/* Determine protocol families for which interfaces exist. Linux version. - Copyright (C) 2003-2017 Free Software Foundation, Inc. - This file is part of the GNU C Library. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; if not, see - <http://www.gnu.org/licenses/>. */ - -#include <assert.h> -#include <errno.h> -#include <ifaddrs.h> -#include <netdb.h> -#include <stddef.h> -#include <string.h> -#include <time.h> -#include <unistd.h> -#include <stdint.h> -#include <sys/socket.h> - -#include <asm/types.h> -#include <linux/netlink.h> -#include <linux/rtnetlink.h> - -#include <not-cancel.h> -#include <libc-lock.h> -#include <atomic.h> -#include <nscd/nscd-client.h> - -#include "netlinkaccess.h" - -#ifndef IFA_F_HOMEADDRESS -# define IFA_F_HOMEADDRESS 0 -#endif -#ifndef IFA_F_OPTIMISTIC -# define IFA_F_OPTIMISTIC 0 -#endif - - -struct cached_data -{ - uint32_t timestamp; - uint32_t usecnt; - bool seen_ipv4; - bool seen_ipv6; - size_t in6ailen; - struct in6addrinfo in6ai[0]; -}; - -static struct cached_data noai6ai_cached = - { - .usecnt = 1, /* Make sure we never try to delete this entry. */ - .in6ailen = 0 - }; - -static struct cached_data *cache; -__libc_lock_define_initialized (static, lock); - - -#if IS_IN (nscd) -static uint32_t nl_timestamp; - -uint32_t -__bump_nl_timestamp (void) -{ - if (atomic_increment_val (&nl_timestamp) == 0) - atomic_increment (&nl_timestamp); - - return nl_timestamp; -} -#endif - -static inline uint32_t -get_nl_timestamp (void) -{ -#if IS_IN (nscd) - return nl_timestamp; -#elif defined USE_NSCD - return __nscd_get_nl_timestamp (); -#else - return 0; -#endif -} - -static inline bool -cache_valid_p (void) -{ - if (cache != NULL) - { - uint32_t timestamp = get_nl_timestamp (); - return timestamp != 0 && cache->timestamp == timestamp; - } - return false; -} - - -static struct cached_data * -make_request (int fd, pid_t pid) -{ - struct cached_data *result = NULL; - - size_t result_len = 0; - size_t result_cap = 32; - - struct req - { - struct nlmsghdr nlh; - struct rtgenmsg g; - /* struct rtgenmsg consists of a single byte. This means there - are three bytes of padding included in the REQ definition. - We make them explicit here. */ - char pad[3]; - } req; - struct sockaddr_nl nladdr; - - req.nlh.nlmsg_len = sizeof (req); - req.nlh.nlmsg_type = RTM_GETADDR; - req.nlh.nlmsg_flags = NLM_F_ROOT | NLM_F_MATCH | NLM_F_REQUEST; - req.nlh.nlmsg_pid = 0; - req.nlh.nlmsg_seq = time (NULL); - req.g.rtgen_family = AF_UNSPEC; - - assert (sizeof (req) - offsetof (struct req, pad) == 3); - memset (req.pad, '\0', sizeof (req.pad)); - - memset (&nladdr, '\0', sizeof (nladdr)); - nladdr.nl_family = AF_NETLINK; - -#ifdef PAGE_SIZE - const size_t buf_size = PAGE_SIZE; -#else - const size_t buf_size = 4096; -#endif - char buf[buf_size]; - - struct iovec iov = { buf, buf_size }; - - if (TEMP_FAILURE_RETRY (__sendto (fd, (void *) &req, sizeof (req), 0, - (struct sockaddr *) &nladdr, - sizeof (nladdr))) < 0) - goto out_fail; - - bool done = false; - - bool seen_ipv4 = false; - bool seen_ipv6 = false; - - do - { - struct msghdr msg = - { - .msg_name = (void *) &nladdr, - .msg_namelen = sizeof (nladdr), - .msg_iov = &iov, - .msg_iovlen = 1, - .msg_control = NULL, - .msg_controllen = 0, - .msg_flags = 0 - }; - - ssize_t read_len = TEMP_FAILURE_RETRY (__recvmsg (fd, &msg, 0)); - __netlink_assert_response (fd, read_len); - if (read_len < 0) - goto out_fail; - - if (msg.msg_flags & MSG_TRUNC) - goto out_fail; - - struct nlmsghdr *nlmh; - for (nlmh = (struct nlmsghdr *) buf; - NLMSG_OK (nlmh, (size_t) read_len); - nlmh = (struct nlmsghdr *) NLMSG_NEXT (nlmh, read_len)) - { - if (nladdr.nl_pid != 0 || (pid_t) nlmh->nlmsg_pid != pid - || nlmh->nlmsg_seq != req.nlh.nlmsg_seq) - continue; - - if (nlmh->nlmsg_type == RTM_NEWADDR) - { - struct ifaddrmsg *ifam = (struct ifaddrmsg *) NLMSG_DATA (nlmh); - struct rtattr *rta = IFA_RTA (ifam); - size_t len = nlmh->nlmsg_len - NLMSG_LENGTH (sizeof (*ifam)); - - if (ifam->ifa_family != AF_INET - && ifam->ifa_family != AF_INET6) - continue; - - const void *local = NULL; - const void *address = NULL; - while (RTA_OK (rta, len)) - { - switch (rta->rta_type) - { - case IFA_LOCAL: - local = RTA_DATA (rta); - break; - - case IFA_ADDRESS: - address = RTA_DATA (rta); - goto out; - } - - rta = RTA_NEXT (rta, len); - } - - if (local != NULL) - { - address = local; - out: - if (ifam->ifa_family == AF_INET) - { - if (*(const in_addr_t *) address - != htonl (INADDR_LOOPBACK)) - seen_ipv4 = true; - } - else - { - if (!IN6_IS_ADDR_LOOPBACK (address)) - seen_ipv6 = true; - } - } - - if (result_len == 0 || result_len == result_cap) - { - result_cap = 2 * result_cap; - result = realloc (result, sizeof (*result) - + result_cap - * sizeof (struct in6addrinfo)); - } - - if (!result) - goto out_fail; - - struct in6addrinfo *info = &result->in6ai[result_len++]; - - info->flags = (((ifam->ifa_flags - & (IFA_F_DEPRECATED | IFA_F_OPTIMISTIC)) - ? in6ai_deprecated : 0) - | ((ifam->ifa_flags & IFA_F_HOMEADDRESS) - ? in6ai_homeaddress : 0)); - info->prefixlen = ifam->ifa_prefixlen; - info->index = ifam->ifa_index; - if (ifam->ifa_family == AF_INET) - { - info->addr[0] = 0; - info->addr[1] = 0; - info->addr[2] = htonl (0xffff); - info->addr[3] = *(const in_addr_t *) address; - } - else - memcpy (info->addr, address, sizeof (info->addr)); - } - else if (nlmh->nlmsg_type == NLMSG_DONE) - /* We found the end, leave the loop. */ - done = true; - } - } - while (! done); - - if (seen_ipv6 && result != NULL) - { - result->timestamp = get_nl_timestamp (); - result->usecnt = 2; - result->seen_ipv4 = seen_ipv4; - result->seen_ipv6 = true; - result->in6ailen = result_len; - } - else - { - free (result); - - atomic_add (&noai6ai_cached.usecnt, 2); - noai6ai_cached.seen_ipv4 = seen_ipv4; - noai6ai_cached.seen_ipv6 = seen_ipv6; - result = &noai6ai_cached; - } - - return result; - - out_fail: - - free (result); - return NULL; -} - - -void -attribute_hidden -__check_pf (bool *seen_ipv4, bool *seen_ipv6, - struct in6addrinfo **in6ai, size_t *in6ailen) -{ - *in6ai = NULL; - *in6ailen = 0; - - struct cached_data *olddata = NULL; - struct cached_data *data = NULL; - - __libc_lock_lock (lock); - - if (cache_valid_p ()) - { - data = cache; - atomic_increment (&cache->usecnt); - } - else - { - int fd = __socket (PF_NETLINK, SOCK_RAW, NETLINK_ROUTE); - - if (__glibc_likely (fd >= 0)) - { - struct sockaddr_nl nladdr; - memset (&nladdr, '\0', sizeof (nladdr)); - nladdr.nl_family = AF_NETLINK; - - socklen_t addr_len = sizeof (nladdr); - - if (__bind (fd, (struct sockaddr *) &nladdr, sizeof (nladdr)) == 0 - && __getsockname (fd, (struct sockaddr *) &nladdr, - &addr_len) == 0) - data = make_request (fd, nladdr.nl_pid); - - close_not_cancel_no_status (fd); - } - - if (data != NULL) - { - olddata = cache; - cache = data; - } - } - - __libc_lock_unlock (lock); - - if (data != NULL) - { - /* It worked. */ - *seen_ipv4 = data->seen_ipv4; - *seen_ipv6 = data->seen_ipv6; - *in6ailen = data->in6ailen; - *in6ai = data->in6ai; - - if (olddata != NULL && olddata->usecnt > 0 - && atomic_add_zero (&olddata->usecnt, -1)) - free (olddata); - - return; - } - - /* We cannot determine what interfaces are available. Be - pessimistic. */ - *seen_ipv4 = true; - *seen_ipv6 = true; -} - -/* Free the cache if it has been allocated. */ -libc_freeres_fn (freecache) -{ - if (cache) - __free_in6ai (cache->in6ai); -} - -void -__free_in6ai (struct in6addrinfo *ai) -{ - if (ai != NULL) - { - struct cached_data *data = - (struct cached_data *) ((char *) ai - - offsetof (struct cached_data, in6ai)); - - if (atomic_add_zero (&data->usecnt, -1)) - { - __libc_lock_lock (lock); - - if (data->usecnt == 0) - /* Still unused. */ - free (data); - - __libc_lock_unlock (lock); - } - } -} |