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-rw-r--r--src/basic/socket-util.c769
1 files changed, 769 insertions, 0 deletions
diff --git a/src/basic/socket-util.c b/src/basic/socket-util.c
new file mode 100644
index 0000000000..e8bb10dc9b
--- /dev/null
+++ b/src/basic/socket-util.c
@@ -0,0 +1,769 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+ This file is part of systemd.
+
+ Copyright 2010 Lennart Poettering
+
+ systemd 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.
+
+ systemd 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 systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <arpa/inet.h>
+#include <stdio.h>
+#include <net/if.h>
+#include <sys/types.h>
+#include <stddef.h>
+#include <netdb.h>
+
+#include "macro.h"
+#include "path-util.h"
+#include "util.h"
+#include "socket-util.h"
+#include "missing.h"
+#include "fileio.h"
+#include "formats-util.h"
+
+int socket_address_parse(SocketAddress *a, const char *s) {
+ char *e, *n;
+ unsigned u;
+ int r;
+
+ assert(a);
+ assert(s);
+
+ zero(*a);
+ a->type = SOCK_STREAM;
+
+ if (*s == '[') {
+ /* IPv6 in [x:.....:z]:p notation */
+
+ e = strchr(s+1, ']');
+ if (!e)
+ return -EINVAL;
+
+ n = strndupa(s+1, e-s-1);
+
+ errno = 0;
+ if (inet_pton(AF_INET6, n, &a->sockaddr.in6.sin6_addr) <= 0)
+ return errno > 0 ? -errno : -EINVAL;
+
+ e++;
+ if (*e != ':')
+ return -EINVAL;
+
+ e++;
+ r = safe_atou(e, &u);
+ if (r < 0)
+ return r;
+
+ if (u <= 0 || u > 0xFFFF)
+ return -EINVAL;
+
+ a->sockaddr.in6.sin6_family = AF_INET6;
+ a->sockaddr.in6.sin6_port = htons((uint16_t) u);
+ a->size = sizeof(struct sockaddr_in6);
+
+ } else if (*s == '/') {
+ /* AF_UNIX socket */
+
+ size_t l;
+
+ l = strlen(s);
+ if (l >= sizeof(a->sockaddr.un.sun_path))
+ return -EINVAL;
+
+ a->sockaddr.un.sun_family = AF_UNIX;
+ memcpy(a->sockaddr.un.sun_path, s, l);
+ a->size = offsetof(struct sockaddr_un, sun_path) + l + 1;
+
+ } else if (*s == '@') {
+ /* Abstract AF_UNIX socket */
+ size_t l;
+
+ l = strlen(s+1);
+ if (l >= sizeof(a->sockaddr.un.sun_path) - 1)
+ return -EINVAL;
+
+ a->sockaddr.un.sun_family = AF_UNIX;
+ memcpy(a->sockaddr.un.sun_path+1, s+1, l);
+ a->size = offsetof(struct sockaddr_un, sun_path) + 1 + l;
+
+ } else {
+ e = strchr(s, ':');
+ if (e) {
+ r = safe_atou(e+1, &u);
+ if (r < 0)
+ return r;
+
+ if (u <= 0 || u > 0xFFFF)
+ return -EINVAL;
+
+ n = strndupa(s, e-s);
+
+ /* IPv4 in w.x.y.z:p notation? */
+ r = inet_pton(AF_INET, n, &a->sockaddr.in.sin_addr);
+ if (r < 0)
+ return -errno;
+
+ if (r > 0) {
+ /* Gotcha, it's a traditional IPv4 address */
+ a->sockaddr.in.sin_family = AF_INET;
+ a->sockaddr.in.sin_port = htons((uint16_t) u);
+ a->size = sizeof(struct sockaddr_in);
+ } else {
+ unsigned idx;
+
+ if (strlen(n) > IF_NAMESIZE-1)
+ return -EINVAL;
+
+ /* Uh, our last resort, an interface name */
+ idx = if_nametoindex(n);
+ if (idx == 0)
+ return -EINVAL;
+
+ a->sockaddr.in6.sin6_family = AF_INET6;
+ a->sockaddr.in6.sin6_port = htons((uint16_t) u);
+ a->sockaddr.in6.sin6_scope_id = idx;
+ a->sockaddr.in6.sin6_addr = in6addr_any;
+ a->size = sizeof(struct sockaddr_in6);
+ }
+ } else {
+
+ /* Just a port */
+ r = safe_atou(s, &u);
+ if (r < 0)
+ return r;
+
+ if (u <= 0 || u > 0xFFFF)
+ return -EINVAL;
+
+ if (socket_ipv6_is_supported()) {
+ a->sockaddr.in6.sin6_family = AF_INET6;
+ a->sockaddr.in6.sin6_port = htons((uint16_t) u);
+ a->sockaddr.in6.sin6_addr = in6addr_any;
+ a->size = sizeof(struct sockaddr_in6);
+ } else {
+ a->sockaddr.in.sin_family = AF_INET;
+ a->sockaddr.in.sin_port = htons((uint16_t) u);
+ a->sockaddr.in.sin_addr.s_addr = INADDR_ANY;
+ a->size = sizeof(struct sockaddr_in);
+ }
+ }
+ }
+
+ return 0;
+}
+
+int socket_address_parse_and_warn(SocketAddress *a, const char *s) {
+ SocketAddress b;
+ int r;
+
+ /* Similar to socket_address_parse() but warns for IPv6 sockets when we don't support them. */
+
+ r = socket_address_parse(&b, s);
+ if (r < 0)
+ return r;
+
+ if (!socket_ipv6_is_supported() && b.sockaddr.sa.sa_family == AF_INET6) {
+ log_warning("Binding to IPv6 address not available since kernel does not support IPv6.");
+ return -EAFNOSUPPORT;
+ }
+
+ *a = b;
+ return 0;
+}
+
+int socket_address_parse_netlink(SocketAddress *a, const char *s) {
+ int family;
+ unsigned group = 0;
+ _cleanup_free_ char *sfamily = NULL;
+ assert(a);
+ assert(s);
+
+ zero(*a);
+ a->type = SOCK_RAW;
+
+ errno = 0;
+ if (sscanf(s, "%ms %u", &sfamily, &group) < 1)
+ return errno > 0 ? -errno : -EINVAL;
+
+ family = netlink_family_from_string(sfamily);
+ if (family < 0)
+ return -EINVAL;
+
+ a->sockaddr.nl.nl_family = AF_NETLINK;
+ a->sockaddr.nl.nl_groups = group;
+
+ a->type = SOCK_RAW;
+ a->size = sizeof(struct sockaddr_nl);
+ a->protocol = family;
+
+ return 0;
+}
+
+int socket_address_verify(const SocketAddress *a) {
+ assert(a);
+
+ switch (socket_address_family(a)) {
+
+ case AF_INET:
+ if (a->size != sizeof(struct sockaddr_in))
+ return -EINVAL;
+
+ if (a->sockaddr.in.sin_port == 0)
+ return -EINVAL;
+
+ if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM)
+ return -EINVAL;
+
+ return 0;
+
+ case AF_INET6:
+ if (a->size != sizeof(struct sockaddr_in6))
+ return -EINVAL;
+
+ if (a->sockaddr.in6.sin6_port == 0)
+ return -EINVAL;
+
+ if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM)
+ return -EINVAL;
+
+ return 0;
+
+ case AF_UNIX:
+ if (a->size < offsetof(struct sockaddr_un, sun_path))
+ return -EINVAL;
+
+ if (a->size > offsetof(struct sockaddr_un, sun_path)) {
+
+ if (a->sockaddr.un.sun_path[0] != 0) {
+ char *e;
+
+ /* path */
+ e = memchr(a->sockaddr.un.sun_path, 0, sizeof(a->sockaddr.un.sun_path));
+ if (!e)
+ return -EINVAL;
+
+ if (a->size != offsetof(struct sockaddr_un, sun_path) + (e - a->sockaddr.un.sun_path) + 1)
+ return -EINVAL;
+ }
+ }
+
+ if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM && a->type != SOCK_SEQPACKET)
+ return -EINVAL;
+
+ return 0;
+
+ case AF_NETLINK:
+
+ if (a->size != sizeof(struct sockaddr_nl))
+ return -EINVAL;
+
+ if (a->type != SOCK_RAW && a->type != SOCK_DGRAM)
+ return -EINVAL;
+
+ return 0;
+
+ default:
+ return -EAFNOSUPPORT;
+ }
+}
+
+int socket_address_print(const SocketAddress *a, char **ret) {
+ int r;
+
+ assert(a);
+ assert(ret);
+
+ r = socket_address_verify(a);
+ if (r < 0)
+ return r;
+
+ if (socket_address_family(a) == AF_NETLINK) {
+ _cleanup_free_ char *sfamily = NULL;
+
+ r = netlink_family_to_string_alloc(a->protocol, &sfamily);
+ if (r < 0)
+ return r;
+
+ r = asprintf(ret, "%s %u", sfamily, a->sockaddr.nl.nl_groups);
+ if (r < 0)
+ return -ENOMEM;
+
+ return 0;
+ }
+
+ return sockaddr_pretty(&a->sockaddr.sa, a->size, false, true, ret);
+}
+
+bool socket_address_can_accept(const SocketAddress *a) {
+ assert(a);
+
+ return
+ a->type == SOCK_STREAM ||
+ a->type == SOCK_SEQPACKET;
+}
+
+bool socket_address_equal(const SocketAddress *a, const SocketAddress *b) {
+ assert(a);
+ assert(b);
+
+ /* Invalid addresses are unequal to all */
+ if (socket_address_verify(a) < 0 ||
+ socket_address_verify(b) < 0)
+ return false;
+
+ if (a->type != b->type)
+ return false;
+
+ if (socket_address_family(a) != socket_address_family(b))
+ return false;
+
+ switch (socket_address_family(a)) {
+
+ case AF_INET:
+ if (a->sockaddr.in.sin_addr.s_addr != b->sockaddr.in.sin_addr.s_addr)
+ return false;
+
+ if (a->sockaddr.in.sin_port != b->sockaddr.in.sin_port)
+ return false;
+
+ break;
+
+ case AF_INET6:
+ if (memcmp(&a->sockaddr.in6.sin6_addr, &b->sockaddr.in6.sin6_addr, sizeof(a->sockaddr.in6.sin6_addr)) != 0)
+ return false;
+
+ if (a->sockaddr.in6.sin6_port != b->sockaddr.in6.sin6_port)
+ return false;
+
+ break;
+
+ case AF_UNIX:
+ if (a->size <= offsetof(struct sockaddr_un, sun_path) ||
+ b->size <= offsetof(struct sockaddr_un, sun_path))
+ return false;
+
+ if ((a->sockaddr.un.sun_path[0] == 0) != (b->sockaddr.un.sun_path[0] == 0))
+ return false;
+
+ if (a->sockaddr.un.sun_path[0]) {
+ if (!path_equal_or_files_same(a->sockaddr.un.sun_path, b->sockaddr.un.sun_path))
+ return false;
+ } else {
+ if (a->size != b->size)
+ return false;
+
+ if (memcmp(a->sockaddr.un.sun_path, b->sockaddr.un.sun_path, a->size) != 0)
+ return false;
+ }
+
+ break;
+
+ case AF_NETLINK:
+ if (a->protocol != b->protocol)
+ return false;
+
+ if (a->sockaddr.nl.nl_groups != b->sockaddr.nl.nl_groups)
+ return false;
+
+ break;
+
+ default:
+ /* Cannot compare, so we assume the addresses are different */
+ return false;
+ }
+
+ return true;
+}
+
+bool socket_address_is(const SocketAddress *a, const char *s, int type) {
+ struct SocketAddress b;
+
+ assert(a);
+ assert(s);
+
+ if (socket_address_parse(&b, s) < 0)
+ return false;
+
+ b.type = type;
+
+ return socket_address_equal(a, &b);
+}
+
+bool socket_address_is_netlink(const SocketAddress *a, const char *s) {
+ struct SocketAddress b;
+
+ assert(a);
+ assert(s);
+
+ if (socket_address_parse_netlink(&b, s) < 0)
+ return false;
+
+ return socket_address_equal(a, &b);
+}
+
+const char* socket_address_get_path(const SocketAddress *a) {
+ assert(a);
+
+ if (socket_address_family(a) != AF_UNIX)
+ return NULL;
+
+ if (a->sockaddr.un.sun_path[0] == 0)
+ return NULL;
+
+ return a->sockaddr.un.sun_path;
+}
+
+bool socket_ipv6_is_supported(void) {
+ _cleanup_free_ char *l = NULL;
+
+ if (access("/sys/module/ipv6", F_OK) != 0)
+ return false;
+
+ /* If we can't check "disable" parameter, assume enabled */
+ if (read_one_line_file("/sys/module/ipv6/parameters/disable", &l) < 0)
+ return true;
+
+ /* If module was loaded with disable=1 no IPv6 available */
+ return l[0] == '0';
+}
+
+bool socket_address_matches_fd(const SocketAddress *a, int fd) {
+ SocketAddress b;
+ socklen_t solen;
+
+ assert(a);
+ assert(fd >= 0);
+
+ b.size = sizeof(b.sockaddr);
+ if (getsockname(fd, &b.sockaddr.sa, &b.size) < 0)
+ return false;
+
+ if (b.sockaddr.sa.sa_family != a->sockaddr.sa.sa_family)
+ return false;
+
+ solen = sizeof(b.type);
+ if (getsockopt(fd, SOL_SOCKET, SO_TYPE, &b.type, &solen) < 0)
+ return false;
+
+ if (b.type != a->type)
+ return false;
+
+ if (a->protocol != 0) {
+ solen = sizeof(b.protocol);
+ if (getsockopt(fd, SOL_SOCKET, SO_PROTOCOL, &b.protocol, &solen) < 0)
+ return false;
+
+ if (b.protocol != a->protocol)
+ return false;
+ }
+
+ return socket_address_equal(a, &b);
+}
+
+int sockaddr_port(const struct sockaddr *_sa) {
+ union sockaddr_union *sa = (union sockaddr_union*) _sa;
+
+ assert(sa);
+
+ if (!IN_SET(sa->sa.sa_family, AF_INET, AF_INET6))
+ return -EAFNOSUPPORT;
+
+ return ntohs(sa->sa.sa_family == AF_INET6 ?
+ sa->in6.sin6_port :
+ sa->in.sin_port);
+}
+
+int sockaddr_pretty(const struct sockaddr *_sa, socklen_t salen, bool translate_ipv6, bool include_port, char **ret) {
+ union sockaddr_union *sa = (union sockaddr_union*) _sa;
+ char *p;
+ int r;
+
+ assert(sa);
+ assert(salen >= sizeof(sa->sa.sa_family));
+
+ switch (sa->sa.sa_family) {
+
+ case AF_INET: {
+ uint32_t a;
+
+ a = ntohl(sa->in.sin_addr.s_addr);
+
+ if (include_port)
+ r = asprintf(&p,
+ "%u.%u.%u.%u:%u",
+ a >> 24, (a >> 16) & 0xFF, (a >> 8) & 0xFF, a & 0xFF,
+ ntohs(sa->in.sin_port));
+ else
+ r = asprintf(&p,
+ "%u.%u.%u.%u",
+ a >> 24, (a >> 16) & 0xFF, (a >> 8) & 0xFF, a & 0xFF);
+ if (r < 0)
+ return -ENOMEM;
+ break;
+ }
+
+ case AF_INET6: {
+ static const unsigned char ipv4_prefix[] = {
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF
+ };
+
+ if (translate_ipv6 &&
+ memcmp(&sa->in6.sin6_addr, ipv4_prefix, sizeof(ipv4_prefix)) == 0) {
+ const uint8_t *a = sa->in6.sin6_addr.s6_addr+12;
+ if (include_port)
+ r = asprintf(&p,
+ "%u.%u.%u.%u:%u",
+ a[0], a[1], a[2], a[3],
+ ntohs(sa->in6.sin6_port));
+ else
+ r = asprintf(&p,
+ "%u.%u.%u.%u",
+ a[0], a[1], a[2], a[3]);
+ if (r < 0)
+ return -ENOMEM;
+ } else {
+ char a[INET6_ADDRSTRLEN];
+
+ inet_ntop(AF_INET6, &sa->in6.sin6_addr, a, sizeof(a));
+
+ if (include_port) {
+ r = asprintf(&p,
+ "[%s]:%u",
+ a,
+ ntohs(sa->in6.sin6_port));
+ if (r < 0)
+ return -ENOMEM;
+ } else {
+ p = strdup(a);
+ if (!p)
+ return -ENOMEM;
+ }
+ }
+
+ break;
+ }
+
+ case AF_UNIX:
+ if (salen <= offsetof(struct sockaddr_un, sun_path)) {
+ p = strdup("<unnamed>");
+ if (!p)
+ return -ENOMEM;
+
+ } else if (sa->un.sun_path[0] == 0) {
+ /* abstract */
+
+ /* FIXME: We assume we can print the
+ * socket path here and that it hasn't
+ * more than one NUL byte. That is
+ * actually an invalid assumption */
+
+ p = new(char, sizeof(sa->un.sun_path)+1);
+ if (!p)
+ return -ENOMEM;
+
+ p[0] = '@';
+ memcpy(p+1, sa->un.sun_path+1, sizeof(sa->un.sun_path)-1);
+ p[sizeof(sa->un.sun_path)] = 0;
+
+ } else {
+ p = strndup(sa->un.sun_path, sizeof(sa->un.sun_path));
+ if (!ret)
+ return -ENOMEM;
+ }
+
+ break;
+
+ default:
+ return -EOPNOTSUPP;
+ }
+
+
+ *ret = p;
+ return 0;
+}
+
+int getpeername_pretty(int fd, char **ret) {
+ union sockaddr_union sa;
+ socklen_t salen = sizeof(sa);
+ int r;
+
+ assert(fd >= 0);
+ assert(ret);
+
+ if (getpeername(fd, &sa.sa, &salen) < 0)
+ return -errno;
+
+ if (sa.sa.sa_family == AF_UNIX) {
+ struct ucred ucred = {};
+
+ /* UNIX connection sockets are anonymous, so let's use
+ * PID/UID as pretty credentials instead */
+
+ r = getpeercred(fd, &ucred);
+ if (r < 0)
+ return r;
+
+ if (asprintf(ret, "PID "PID_FMT"/UID "UID_FMT, ucred.pid, ucred.uid) < 0)
+ return -ENOMEM;
+
+ return 0;
+ }
+
+ /* For remote sockets we translate IPv6 addresses back to IPv4
+ * if applicable, since that's nicer. */
+
+ return sockaddr_pretty(&sa.sa, salen, true, true, ret);
+}
+
+int getsockname_pretty(int fd, char **ret) {
+ union sockaddr_union sa;
+ socklen_t salen = sizeof(sa);
+
+ assert(fd >= 0);
+ assert(ret);
+
+ if (getsockname(fd, &sa.sa, &salen) < 0)
+ return -errno;
+
+ /* For local sockets we do not translate IPv6 addresses back
+ * to IPv6 if applicable, since this is usually used for
+ * listening sockets where the difference between IPv4 and
+ * IPv6 matters. */
+
+ return sockaddr_pretty(&sa.sa, salen, false, true, ret);
+}
+
+int socknameinfo_pretty(union sockaddr_union *sa, socklen_t salen, char **_ret) {
+ int r;
+ char host[NI_MAXHOST], *ret;
+
+ assert(_ret);
+
+ r = getnameinfo(&sa->sa, salen, host, sizeof(host), NULL, 0,
+ NI_IDN|NI_IDN_USE_STD3_ASCII_RULES);
+ if (r != 0) {
+ int saved_errno = errno;
+
+ r = sockaddr_pretty(&sa->sa, salen, true, true, &ret);
+ if (r < 0)
+ return log_error_errno(r, "sockadd_pretty() failed: %m");
+
+ log_debug_errno(saved_errno, "getnameinfo(%s) failed: %m", ret);
+ } else {
+ ret = strdup(host);
+ if (!ret)
+ return log_oom();
+ }
+
+ *_ret = ret;
+ return 0;
+}
+
+int getnameinfo_pretty(int fd, char **ret) {
+ union sockaddr_union sa;
+ socklen_t salen = sizeof(sa);
+
+ assert(fd >= 0);
+ assert(ret);
+
+ if (getsockname(fd, &sa.sa, &salen) < 0)
+ return log_error_errno(errno, "getsockname(%d) failed: %m", fd);
+
+ return socknameinfo_pretty(&sa, salen, ret);
+}
+
+int socket_address_unlink(SocketAddress *a) {
+ assert(a);
+
+ if (socket_address_family(a) != AF_UNIX)
+ return 0;
+
+ if (a->sockaddr.un.sun_path[0] == 0)
+ return 0;
+
+ if (unlink(a->sockaddr.un.sun_path) < 0)
+ return -errno;
+
+ return 1;
+}
+
+static const char* const netlink_family_table[] = {
+ [NETLINK_ROUTE] = "route",
+ [NETLINK_FIREWALL] = "firewall",
+ [NETLINK_INET_DIAG] = "inet-diag",
+ [NETLINK_NFLOG] = "nflog",
+ [NETLINK_XFRM] = "xfrm",
+ [NETLINK_SELINUX] = "selinux",
+ [NETLINK_ISCSI] = "iscsi",
+ [NETLINK_AUDIT] = "audit",
+ [NETLINK_FIB_LOOKUP] = "fib-lookup",
+ [NETLINK_CONNECTOR] = "connector",
+ [NETLINK_NETFILTER] = "netfilter",
+ [NETLINK_IP6_FW] = "ip6-fw",
+ [NETLINK_DNRTMSG] = "dnrtmsg",
+ [NETLINK_KOBJECT_UEVENT] = "kobject-uevent",
+ [NETLINK_GENERIC] = "generic",
+ [NETLINK_SCSITRANSPORT] = "scsitransport",
+ [NETLINK_ECRYPTFS] = "ecryptfs"
+};
+
+DEFINE_STRING_TABLE_LOOKUP_WITH_FALLBACK(netlink_family, int, INT_MAX);
+
+static const char* const socket_address_bind_ipv6_only_table[_SOCKET_ADDRESS_BIND_IPV6_ONLY_MAX] = {
+ [SOCKET_ADDRESS_DEFAULT] = "default",
+ [SOCKET_ADDRESS_BOTH] = "both",
+ [SOCKET_ADDRESS_IPV6_ONLY] = "ipv6-only"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(socket_address_bind_ipv6_only, SocketAddressBindIPv6Only);
+
+bool sockaddr_equal(const union sockaddr_union *a, const union sockaddr_union *b) {
+ assert(a);
+ assert(b);
+
+ if (a->sa.sa_family != b->sa.sa_family)
+ return false;
+
+ if (a->sa.sa_family == AF_INET)
+ return a->in.sin_addr.s_addr == b->in.sin_addr.s_addr;
+
+ if (a->sa.sa_family == AF_INET6)
+ return memcmp(&a->in6.sin6_addr, &b->in6.sin6_addr, sizeof(a->in6.sin6_addr)) == 0;
+
+ return false;
+}
+
+char* ether_addr_to_string(const struct ether_addr *addr, char buffer[ETHER_ADDR_TO_STRING_MAX]) {
+ assert(addr);
+ assert(buffer);
+
+ /* Like ether_ntoa() but uses %02x instead of %x to print
+ * ethernet addresses, which makes them look less funny. Also,
+ * doesn't use a static buffer. */
+
+ sprintf(buffer, "%02x:%02x:%02x:%02x:%02x:%02x",
+ addr->ether_addr_octet[0],
+ addr->ether_addr_octet[1],
+ addr->ether_addr_octet[2],
+ addr->ether_addr_octet[3],
+ addr->ether_addr_octet[4],
+ addr->ether_addr_octet[5]);
+
+ return buffer;
+}