X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fshared%2Fsocket-util.c;h=c832cfe3f9b9c87ed5bd826e117494d7dc46db14;hp=f6ddea31838512e4435cf4cad1882f1280f13adf;hb=fc25ad25e019eb2fbce9d3c4be052098cb2c7122;hpb=37d3ab1b7e114f0fb6dfb2e7273569b42794b76a

diff --git a/src/shared/socket-util.c b/src/shared/socket-util.c
index f6ddea318..c832cfe3f 100644
--- a/src/shared/socket-util.c
+++ b/src/shared/socket-util.c
@@ -19,31 +19,27 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
-#include <assert.h>
 #include <string.h>
 #include <unistd.h>
 #include <errno.h>
-#include <stdlib.h>
 #include <arpa/inet.h>
 #include <stdio.h>
 #include <net/if.h>
 #include <sys/types.h>
-#include <sys/stat.h>
 #include <stddef.h>
-#include <sys/ioctl.h>
+#include <netdb.h>
 
 #include "macro.h"
-#include "util.h"
-#include "mkdir.h"
 #include "path-util.h"
+#include "util.h"
 #include "socket-util.h"
 #include "missing.h"
 #include "fileio.h"
 
 int socket_address_parse(SocketAddress *a, const char *s) {
-        int r;
         char *e, *n;
         unsigned u;
+        int r;
 
         assert(a);
         assert(s);
@@ -59,26 +55,23 @@ int socket_address_parse(SocketAddress *a, const char *s) {
                         return -EAFNOSUPPORT;
                 }
 
-                if (!(e = strchr(s+1, ']')))
+                e = strchr(s+1, ']');
+                if (!e)
                         return -EINVAL;
 
-                if (!(n = strndup(s+1, e-s-1)))
-                        return -ENOMEM;
+                n = strndupa(s+1, e-s-1);
 
                 errno = 0;
-                if (inet_pton(AF_INET6, n, &a->sockaddr.in6.sin6_addr) <= 0) {
-                        free(n);
-                        return errno != 0 ? -errno : -EINVAL;
-                }
-
-                free(n);
+                if (inet_pton(AF_INET6, n, &a->sockaddr.in6.sin6_addr) <= 0)
+                        return errno > 0 ? -errno : -EINVAL;
 
                 e++;
                 if (*e != ':')
                         return -EINVAL;
 
                 e++;
-                if ((r = safe_atou(e, &u)) < 0)
+                r = safe_atou(e, &u);
+                if (r < 0)
                         return r;
 
                 if (u <= 0 || u > 0xFFFF)
@@ -114,43 +107,35 @@ int socket_address_parse(SocketAddress *a, const char *s) {
                 a->size = offsetof(struct sockaddr_un, sun_path) + 1 + l;
 
         } else {
-
-                if ((e = strchr(s, ':'))) {
-
-                        if ((r = safe_atou(e+1, &u)) < 0)
+                e = strchr(s, ':');
+                if (e) {
+                        r = safe_atou(e+1, &u);
+                        if (r < 0)
                                 return r;
 
                         if (u <= 0 || u > 0xFFFF)
                                 return -EINVAL;
 
-                        if (!(n = strndup(s, e-s)))
-                                return -ENOMEM;
+                        n = strndupa(s, e-s);
 
                         /* IPv4 in w.x.y.z:p notation? */
-                        if ((r = inet_pton(AF_INET, n, &a->sockaddr.in4.sin_addr)) < 0) {
-                                free(n);
+                        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 */
-                                free(n);
-
-                                a->sockaddr.in4.sin_family = AF_INET;
-                                a->sockaddr.in4.sin_port = htons((uint16_t) u);
+                                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) {
-                                        free(n);
+                                if (strlen(n) > IF_NAMESIZE-1)
                                         return -EINVAL;
-                                }
 
                                 /* Uh, our last resort, an interface name */
                                 idx = if_nametoindex(n);
-                                free(n);
-
                                 if (idx == 0)
                                         return -EINVAL;
 
@@ -181,9 +166,9 @@ int socket_address_parse(SocketAddress *a, const char *s) {
                                 a->sockaddr.in6.sin6_addr = in6addr_any;
                                 a->size = sizeof(struct sockaddr_in6);
                         } else {
-                                a->sockaddr.in4.sin_family = AF_INET;
-                                a->sockaddr.in4.sin_port = htons((uint16_t) u);
-                                a->sockaddr.in4.sin_addr.s_addr = INADDR_ANY;
+                                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);
                         }
                 }
@@ -204,7 +189,7 @@ int socket_address_parse_netlink(SocketAddress *a, const char *s) {
 
         errno = 0;
         if (sscanf(s, "%ms %u", &sfamily, &group) < 1)
-                return errno ? -errno : -EINVAL;
+                return errno > 0 ? -errno : -EINVAL;
 
         family = netlink_family_from_string(sfamily);
         if (family < 0)
@@ -229,7 +214,7 @@ int socket_address_verify(const SocketAddress *a) {
                 if (a->size != sizeof(struct sockaddr_in))
                         return -EINVAL;
 
-                if (a->sockaddr.in4.sin_port == 0)
+                if (a->sockaddr.in.sin_port == 0)
                         return -EINVAL;
 
                 if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM)
@@ -259,7 +244,8 @@ int socket_address_verify(const SocketAddress *a) {
                                 char *e;
 
                                 /* path */
-                                if (!(e = memchr(a->sockaddr.un.sun_path, 0, sizeof(a->sockaddr.un.sun_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)
@@ -287,98 +273,31 @@ int socket_address_verify(const SocketAddress *a) {
         }
 }
 
-int socket_address_print(const SocketAddress *a, char **p) {
+int socket_address_print(const SocketAddress *a, char **ret) {
         int r;
+
         assert(a);
-        assert(p);
+        assert(ret);
 
-        if ((r = socket_address_verify(a)) < 0)
+        r = socket_address_verify(a);
+        if (r < 0)
                 return r;
 
-        switch (socket_address_family(a)) {
-
-        case AF_INET: {
-                char *ret;
-
-                if (!(ret = new(char, INET_ADDRSTRLEN+1+5+1)))
-                        return -ENOMEM;
-
-                if (!inet_ntop(AF_INET, &a->sockaddr.in4.sin_addr, ret, INET_ADDRSTRLEN)) {
-                        free(ret);
-                        return -errno;
-                }
-
-                sprintf(strchr(ret, 0), ":%u", ntohs(a->sockaddr.in4.sin_port));
-                *p = ret;
-                return 0;
-        }
-
-        case AF_INET6: {
-                char *ret;
-
-                if (!(ret = new(char, 1+INET6_ADDRSTRLEN+2+5+1)))
-                        return -ENOMEM;
-
-                ret[0] = '[';
-                if (!inet_ntop(AF_INET6, &a->sockaddr.in6.sin6_addr, ret+1, INET6_ADDRSTRLEN)) {
-                        free(ret);
-                        return -errno;
-                }
-
-                sprintf(strchr(ret, 0), "]:%u", ntohs(a->sockaddr.in6.sin6_port));
-                *p = ret;
-                return 0;
-        }
-
-        case AF_UNIX: {
-                char *ret;
-
-                if (a->size <= offsetof(struct sockaddr_un, sun_path)) {
-
-                        if (!(ret = strdup("<unnamed>")))
-                                return -ENOMEM;
-
-                } else if (a->sockaddr.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 */
-
-                        if (!(ret = new(char, sizeof(a->sockaddr.un.sun_path)+1)))
-                                return -ENOMEM;
-
-                        ret[0] = '@';
-                        memcpy(ret+1, a->sockaddr.un.sun_path+1, sizeof(a->sockaddr.un.sun_path)-1);
-                        ret[sizeof(a->sockaddr.un.sun_path)] = 0;
-
-                } else {
-
-                        if (!(ret = strdup(a->sockaddr.un.sun_path)))
-                                return -ENOMEM;
-                }
-
-                *p = ret;
-                return 0;
-        }
-
-        case AF_NETLINK: {
-                char _cleanup_free_ *sfamily = NULL;
+        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(p, "%s %u", sfamily, a->sockaddr.nl.nl_groups);
+
+                r = asprintf(ret, "%s %u", sfamily, a->sockaddr.nl.nl_groups);
                 if (r < 0)
                         return -ENOMEM;
 
                 return 0;
         }
 
-        default:
-                return -EINVAL;
-        }
+        return sockaddr_pretty(&a->sockaddr.sa, a->size, false, true, ret);
 }
 
 bool socket_address_can_accept(const SocketAddress *a) {
@@ -401,19 +320,16 @@ bool socket_address_equal(const SocketAddress *a, const SocketAddress *b) {
         if (a->type != b->type)
                 return false;
 
-        if (a->size != b->size)
-                return false;
-
         if (socket_address_family(a) != socket_address_family(b))
                 return false;
 
         switch (socket_address_family(a)) {
 
         case AF_INET:
-                if (a->sockaddr.in4.sin_addr.s_addr != b->sockaddr.in4.sin_addr.s_addr)
+                if (a->sockaddr.in.sin_addr.s_addr != b->sockaddr.in.sin_addr.s_addr)
                         return false;
 
-                if (a->sockaddr.in4.sin_port != b->sockaddr.in4.sin_port)
+                if (a->sockaddr.in.sin_port != b->sockaddr.in.sin_port)
                         return false;
 
                 break;
@@ -428,14 +344,20 @@ bool socket_address_equal(const SocketAddress *a, const SocketAddress *b) {
                 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 (!strneq(a->sockaddr.un.sun_path, b->sockaddr.un.sun_path, sizeof(a->sockaddr.un.sun_path)))
+                        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;
                 }
@@ -443,7 +365,6 @@ bool socket_address_equal(const SocketAddress *a, const SocketAddress *b) {
                 break;
 
         case AF_NETLINK:
-
                 if (a->protocol != b->protocol)
                         return false;
 
@@ -486,122 +407,290 @@ bool socket_address_is_netlink(const SocketAddress *a, const char *s) {
         return socket_address_equal(a, &b);
 }
 
-bool socket_address_needs_mount(const SocketAddress *a, const char *prefix) {
+const char* socket_address_get_path(const SocketAddress *a) {
         assert(a);
 
         if (socket_address_family(a) != AF_UNIX)
-                return false;
+                return NULL;
 
         if (a->sockaddr.un.sun_path[0] == 0)
-                return false;
+                return NULL;
 
-        return path_startswith(a->sockaddr.un.sun_path, prefix);
+        return a->sockaddr.un.sun_path;
 }
 
 bool socket_ipv6_is_supported(void) {
-        char *l = 0;
-        bool enabled;
+        _cleanup_free_ char *l = NULL;
 
         if (access("/sys/module/ipv6", F_OK) != 0)
-                return 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 1;
+                return true;
 
         /* If module was loaded with disable=1 no IPv6 available */
-        enabled = l[0] == '0';
-        free(l);
-
-        return enabled;
+        return l[0] == '0';
 }
 
 bool socket_address_matches_fd(const SocketAddress *a, int fd) {
-        union sockaddr_union sa;
-        socklen_t salen = sizeof(sa), solen;
-        int protocol, type;
+        SocketAddress b;
+        socklen_t solen;
 
         assert(a);
         assert(fd >= 0);
 
-        if (getsockname(fd, &sa.sa, &salen) < 0)
+        b.size = sizeof(b.sockaddr);
+        if (getsockname(fd, &b.sockaddr.sa, &b.size) < 0)
                 return false;
 
-        if (sa.sa.sa_family != a->sockaddr.sa.sa_family)
+        if (b.sockaddr.sa.sa_family != a->sockaddr.sa.sa_family)
                 return false;
 
-        solen = sizeof(type);
-        if (getsockopt(fd, SOL_SOCKET, SO_TYPE, &type, &solen) < 0)
+        solen = sizeof(b.type);
+        if (getsockopt(fd, SOL_SOCKET, SO_TYPE, &b.type, &solen) < 0)
                 return false;
 
-        if (type != a->type)
+        if (b.type != a->type)
                 return false;
 
         if (a->protocol != 0)  {
-                solen = sizeof(protocol);
-                if (getsockopt(fd, SOL_SOCKET, SO_PROTOCOL, &protocol, &solen) < 0)
+                solen = sizeof(b.protocol);
+                if (getsockopt(fd, SOL_SOCKET, SO_PROTOCOL, &b.protocol, &solen) < 0)
                         return false;
 
-                if (protocol != a->protocol)
+                if (b.protocol != a->protocol)
                         return false;
         }
 
-        switch (sa.sa.sa_family) {
+        return socket_address_equal(a, &b);
+}
 
-        case AF_INET:
-                return sa.in4.sin_port == a->sockaddr.in4.sin_port &&
-                        sa.in4.sin_addr.s_addr == a->sockaddr.in4.sin_addr.s_addr;
+int sockaddr_port(const struct sockaddr *_sa) {
+        union sockaddr_union *sa = (union sockaddr_union*) _sa;
 
-        case AF_INET6:
-                return sa.in6.sin6_port == a->sockaddr.in6.sin6_port &&
-                        memcmp(&sa.in6.sin6_addr, &a->sockaddr.in6.sin6_addr, sizeof(struct in6_addr)) == 0;
+        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:
-                return salen == a->size &&
-                        memcmp(sa.un.sun_path, a->sockaddr.un.sun_path, salen - offsetof(struct sockaddr_un, sun_path)) == 0;
+                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 -ENOTSUP;
         }
 
-        return false;
+
+        *ret = p;
+        return 0;
 }
 
-int make_socket_fd(const char* address, int flags) {
-        SocketAddress a;
-        int fd, r;
-        char _cleanup_free_ *p = NULL;
+int getpeername_pretty(int fd, char **ret) {
+        union sockaddr_union sa;
+        socklen_t salen = sizeof(sa);
+        int r;
 
-        r = socket_address_parse(&a, address);
-        if (r < 0) {
-                log_error("failed to parse socket: %s", strerror(-r));
-                return r;
-        }
+        assert(fd >= 0);
+        assert(ret);
 
-        fd = socket(socket_address_family(&a), flags, 0);
-        if (fd < 0) {
-                log_error("socket(): %m");
+        if (getpeername(fd, &sa.sa, &salen) < 0)
                 return -errno;
-        }
 
-        r = socket_address_print(&a, &p);
-        if (r < 0) {
-                log_error("socket_address_print(): %s", strerror(-r));
-                return r;
+        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;
         }
-        log_info("Listening on %s", p);
 
-        r = bind(fd, &a.sockaddr.sa, a.size);
-        if (r < 0) {
-                log_error("bind to %s: %m", address);
+        /* 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();
         }
 
-        r = listen(fd, SOMAXCONN);
-        if (r < 0) {
-                log_error("listen on %s: %m", address);
+        *_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 fd;
+        return 1;
 }
 
 static const char* const netlink_family_table[] = {
@@ -633,3 +722,38 @@ static const char* const socket_address_bind_ipv6_only_table[_SOCKET_ADDRESS_BIN
 };
 
 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;
+}