diff options
Diffstat (limited to 'REORG.TODO/sysdeps/unix/sysv/linux/if_index.c')
| -rw-r--r-- | REORG.TODO/sysdeps/unix/sysv/linux/if_index.c | 241 |
1 files changed, 241 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/unix/sysv/linux/if_index.c b/REORG.TODO/sysdeps/unix/sysv/linux/if_index.c new file mode 100644 index 0000000000..8ba5eae781 --- /dev/null +++ b/REORG.TODO/sysdeps/unix/sysv/linux/if_index.c @@ -0,0 +1,241 @@ +/* Copyright (C) 1997-2017 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 <alloca.h> +#include <errno.h> +#include <string.h> +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <net/if.h> +#include <sys/socket.h> +#include <sys/ioctl.h> +#include <libc-lock.h> +#include <not-cancel.h> + +#include "netlinkaccess.h" + + +unsigned int +__if_nametoindex (const char *ifname) +{ +#ifndef SIOCGIFINDEX + __set_errno (ENOSYS); + return 0; +#else + struct ifreq ifr; + int fd = __opensock (); + + if (fd < 0) + return 0; + + strncpy (ifr.ifr_name, ifname, sizeof (ifr.ifr_name)); + if (__ioctl (fd, SIOCGIFINDEX, &ifr) < 0) + { + int saved_errno = errno; + close_not_cancel_no_status (fd); + if (saved_errno == EINVAL) + __set_errno (ENOSYS); + return 0; + } + close_not_cancel_no_status (fd); + return ifr.ifr_ifindex; +#endif +} +libc_hidden_def (__if_nametoindex) +weak_alias (__if_nametoindex, if_nametoindex) +libc_hidden_weak (if_nametoindex) + + +void +__if_freenameindex (struct if_nameindex *ifn) +{ + struct if_nameindex *ptr = ifn; + while (ptr->if_name || ptr->if_index) + { + free (ptr->if_name); + ++ptr; + } + free (ifn); +} +libc_hidden_def (__if_freenameindex) +weak_alias (__if_freenameindex, if_freenameindex) +libc_hidden_weak (if_freenameindex) + + +static struct if_nameindex * +if_nameindex_netlink (void) +{ + struct netlink_handle nh = { 0, 0, 0, NULL, NULL }; + struct if_nameindex *idx = NULL; + + if (__netlink_open (&nh) < 0) + return NULL; + + + /* Tell the kernel that we wish to get a list of all + active interfaces. Collect all data for every interface. */ + if (__netlink_request (&nh, RTM_GETLINK) < 0) + goto exit_free; + + /* Count the interfaces. */ + unsigned int nifs = 0; + for (struct netlink_res *nlp = nh.nlm_list; nlp; nlp = nlp->next) + { + struct nlmsghdr *nlh; + size_t size = nlp->size; + + if (nlp->nlh == NULL) + continue; + + /* Walk through all entries we got from the kernel and look, which + message type they contain. */ + for (nlh = nlp->nlh; NLMSG_OK (nlh, size); nlh = NLMSG_NEXT (nlh, size)) + { + /* Check if the message is what we want. */ + if ((pid_t) nlh->nlmsg_pid != nh.pid || nlh->nlmsg_seq != nlp->seq) + continue; + + if (nlh->nlmsg_type == NLMSG_DONE) + break; /* ok */ + + if (nlh->nlmsg_type == RTM_NEWLINK) + ++nifs; + } + } + + idx = malloc ((nifs + 1) * sizeof (struct if_nameindex)); + if (idx == NULL) + { + nomem: + __set_errno (ENOBUFS); + goto exit_free; + } + + /* Add the interfaces. */ + nifs = 0; + for (struct netlink_res *nlp = nh.nlm_list; nlp; nlp = nlp->next) + { + struct nlmsghdr *nlh; + size_t size = nlp->size; + + if (nlp->nlh == NULL) + continue; + + /* Walk through all entries we got from the kernel and look, which + message type they contain. */ + for (nlh = nlp->nlh; NLMSG_OK (nlh, size); nlh = NLMSG_NEXT (nlh, size)) + { + /* Check if the message is what we want. */ + if ((pid_t) nlh->nlmsg_pid != nh.pid || nlh->nlmsg_seq != nlp->seq) + continue; + + if (nlh->nlmsg_type == NLMSG_DONE) + break; /* ok */ + + if (nlh->nlmsg_type == RTM_NEWLINK) + { + struct ifinfomsg *ifim = (struct ifinfomsg *) NLMSG_DATA (nlh); + struct rtattr *rta = IFLA_RTA (ifim); + size_t rtasize = IFLA_PAYLOAD (nlh); + + idx[nifs].if_index = ifim->ifi_index; + + while (RTA_OK (rta, rtasize)) + { + char *rta_data = RTA_DATA (rta); + size_t rta_payload = RTA_PAYLOAD (rta); + + if (rta->rta_type == IFLA_IFNAME) + { + idx[nifs].if_name = __strndup (rta_data, rta_payload); + if (idx[nifs].if_name == NULL) + { + idx[nifs].if_index = 0; + __if_freenameindex (idx); + idx = NULL; + goto nomem; + } + break; + } + + rta = RTA_NEXT (rta, rtasize); + } + + ++nifs; + } + } + } + + idx[nifs].if_index = 0; + idx[nifs].if_name = NULL; + + exit_free: + __netlink_free_handle (&nh); + __netlink_close (&nh); + + return idx; +} + + +struct if_nameindex * +__if_nameindex (void) +{ +#ifndef SIOCGIFINDEX + __set_errno (ENOSYS); + return NULL; +#else + struct if_nameindex *result = if_nameindex_netlink (); + return result; +#endif +} +weak_alias (__if_nameindex, if_nameindex) +libc_hidden_weak (if_nameindex) + + +char * +__if_indextoname (unsigned int ifindex, char *ifname) +{ + /* We may be able to do the conversion directly, rather than searching a + list. This ioctl is not present in kernels before version 2.1.50. */ + struct ifreq ifr; + int fd; + int status; + + fd = __opensock (); + + if (fd < 0) + return NULL; + + ifr.ifr_ifindex = ifindex; + status = __ioctl (fd, SIOCGIFNAME, &ifr); + + close_not_cancel_no_status (fd); + + if (status < 0) + { + if (errno == ENODEV) + /* POSIX requires ENXIO. */ + __set_errno (ENXIO); + + return NULL; + } + else + return strncpy (ifname, ifr.ifr_name, IFNAMSIZ); +} +weak_alias (__if_indextoname, if_indextoname) +libc_hidden_weak (if_indextoname) |