diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/ifaddrs.c')
-rw-r--r-- | sysdeps/unix/sysv/linux/ifaddrs.c | 138 |
1 files changed, 51 insertions, 87 deletions
diff --git a/sysdeps/unix/sysv/linux/ifaddrs.c b/sysdeps/unix/sysv/linux/ifaddrs.c index 02e6935..8a052e2 100644 --- a/sysdeps/unix/sysv/linux/ifaddrs.c +++ b/sysdeps/unix/sysv/linux/ifaddrs.c @@ -1,5 +1,5 @@ /* getifaddrs -- get names and addresses of all network interfaces - Copyright (C) 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc. + Copyright (C) 2003, 2004 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 @@ -17,7 +17,6 @@ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ -#include <alloca.h> #include <assert.h> #include <errno.h> #include <ifaddrs.h> @@ -25,7 +24,6 @@ #include <netinet/in.h> #include <netpacket/packet.h> #include <stdbool.h> -#include <stdint.h> #include <stdlib.h> #include <string.h> #include <sys/ioctl.h> @@ -86,14 +84,13 @@ __netlink_free_handle (struct netlink_handle *h) } -static int +int __netlink_sendreq (struct netlink_handle *h, int type) { - struct req + struct { struct nlmsghdr nlh; struct rtgenmsg g; - char pad[0]; } req; struct sockaddr_nl nladdr; @@ -106,8 +103,6 @@ __netlink_sendreq (struct netlink_handle *h, int type) req.nlh.nlmsg_pid = 0; req.nlh.nlmsg_seq = h->seq; req.g.rtgen_family = AF_UNSPEC; - if (sizeof (req) != offsetof (struct req, pad)) - memset (req.pad, '\0', sizeof (req) - offsetof (struct req, pad)); memset (&nladdr, '\0', sizeof (nladdr)); nladdr.nl_family = AF_NETLINK; @@ -119,40 +114,16 @@ __netlink_sendreq (struct netlink_handle *h, int type) int -__netlink_request (struct netlink_handle *h, int type) +__netlink_receive (struct netlink_handle *h) { struct netlink_res *nlm_next; + char buf[4096]; + struct iovec iov = { buf, sizeof (buf) }; struct sockaddr_nl nladdr; struct nlmsghdr *nlmh; - ssize_t read_len; + int read_len; bool done = false; -#ifdef PAGE_SIZE - /* Help the compiler optimize out the malloc call if PAGE_SIZE - is constant and smaller or equal to PTHREAD_STACK_MIN/4. */ - const size_t buf_size = PAGE_SIZE; -#else - const size_t buf_size = __getpagesize (); -#endif - bool use_malloc = false; - char *buf; - - if (__libc_use_alloca (buf_size)) - buf = alloca (buf_size); - else - { - buf = malloc (buf_size); - if (buf != NULL) - use_malloc = true; - else - goto out_fail; - } - - struct iovec iov = { buf, buf_size }; - - if (__netlink_sendreq (h, type) < 0) - goto out_fail; - while (! done) { struct msghdr msg = @@ -165,25 +136,33 @@ __netlink_request (struct netlink_handle *h, int type) read_len = TEMP_FAILURE_RETRY (__recvmsg (h->fd, &msg, 0)); if (read_len < 0) - goto out_fail; + return -1; - if (nladdr.nl_pid != 0) - continue; + if (msg.msg_flags & MSG_TRUNC) + return -1; - if (__builtin_expect (msg.msg_flags & MSG_TRUNC, 0)) - goto out_fail; + nlm_next = (struct netlink_res *) malloc (sizeof (struct netlink_res) + + read_len); + if (nlm_next == NULL) + return -1; + nlm_next->next = NULL; + nlm_next->nlh = memcpy (nlm_next + 1, buf, read_len); + nlm_next->size = read_len; + nlm_next->seq = h->seq; + if (h->nlm_list == NULL) + h->nlm_list = nlm_next; + else + h->end_ptr->next = nlm_next; + h->end_ptr = nlm_next; - size_t count = 0; - size_t remaining_len = read_len; for (nlmh = (struct nlmsghdr *) buf; - NLMSG_OK (nlmh, remaining_len); - nlmh = (struct nlmsghdr *) NLMSG_NEXT (nlmh, remaining_len)) + NLMSG_OK (nlmh, (size_t) read_len); + nlmh = (struct nlmsghdr *) NLMSG_NEXT (nlmh, read_len)) { - if ((pid_t) nlmh->nlmsg_pid != h->pid + if (nladdr.nl_pid != 0 || (pid_t) nlmh->nlmsg_pid != h->pid || nlmh->nlmsg_seq != h->seq) continue; - ++count; if (nlmh->nlmsg_type == NLMSG_DONE) { /* We found the end, leave the loop. */ @@ -197,38 +176,11 @@ __netlink_request (struct netlink_handle *h, int type) errno = EIO; else errno = -nlerr->error; - goto out_fail; + return -1; } } - - /* If there was nothing with the expected nlmsg_pid and nlmsg_seq, - there is no point to record it. */ - if (count == 0) - continue; - - nlm_next = (struct netlink_res *) malloc (sizeof (struct netlink_res) - + read_len); - if (nlm_next == NULL) - goto out_fail; - nlm_next->next = NULL; - nlm_next->nlh = memcpy (nlm_next + 1, buf, read_len); - nlm_next->size = read_len; - nlm_next->seq = h->seq; - if (h->nlm_list == NULL) - h->nlm_list = nlm_next; - else - h->end_ptr->next = nlm_next; - h->end_ptr = nlm_next; } - - if (use_malloc) - free (buf); return 0; - -out_fail: - if (use_malloc) - free (buf); - return -1; } @@ -316,11 +268,12 @@ getifaddrs (struct ifaddrs **ifap) unsigned int i, newlink, newaddr, newaddr_idx; int *map_newlink_data; size_t ifa_data_size = 0; /* Size to allocate for all ifa_data. */ - char *ifa_data_ptr; /* Pointer to the unused part of memory for + char *ifa_data_ptr; /* Pointer to the unused part of memory for ifa_data. */ int result = 0; - *ifap = NULL; + if (ifap) + *ifap = NULL; if (! __no_netlink_support && __netlink_open (&nh) < 0) { @@ -335,20 +288,28 @@ getifaddrs (struct ifaddrs **ifap) #endif /* 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) + active interfaces. */ + if (__netlink_sendreq (&nh, RTM_GETLINK) < 0) + { + result = -1; + goto exit_close; + } + /* Collect all data for every interface. */ + if (__netlink_receive (&nh) < 0) { result = -1; goto exit_free; } + /* Now ask the kernel for all addresses which are assigned - to an interface and collect all data for every interface. - Since we store the addresses after the interfaces in the - list, we will later always find the interface before the - corresponding addresses. */ + to an interface. Since we store the addresses after the + interfaces in the list, we will later always find the + interface before the corresponding addresses. */ ++nh.seq; - if (__netlink_request (&nh, RTM_GETADDR) < 0) + if (__netlink_sendreq (&nh, RTM_GETADDR) < 0 + /* Collect all data for every interface. */ + || __netlink_receive (&nh) < 0) { result = -1; goto exit_free; @@ -366,7 +327,7 @@ getifaddrs (struct ifaddrs **ifap) continue; /* Walk through all entries we got from the kernel and look, which - message type they contain. */ + 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. */ @@ -462,7 +423,7 @@ getifaddrs (struct ifaddrs **ifap) /* Interfaces are stored in the first "newlink" entries of our list, starting in the order as we got from the kernel. */ - ifa_index = map_newlink (ifim->ifi_index - 1, ifas, + ifa_index = map_newlink (ifim->ifi_index - 1, ifas, map_newlink_data, newlink); ifas[ifa_index].ifa.ifa_flags = ifim->ifi_flags; @@ -801,10 +762,13 @@ getifaddrs (struct ifaddrs **ifap) memmove (ifas, &ifas[newlink], sizeof (struct ifaddrs_storage)); } - *ifap = &ifas[0].ifa; + if (ifap != NULL) + *ifap = &ifas[0].ifa; exit_free: __netlink_free_handle (&nh); + + exit_close: __netlink_close (&nh); return result; |