diff options
| -rw-r--r-- | llmnr-query.c | 36 |
1 files changed, 34 insertions, 2 deletions
diff --git a/llmnr-query.c b/llmnr-query.c index 9aaeee6..7e72836 100644 --- a/llmnr-query.c +++ b/llmnr-query.c @@ -18,6 +18,8 @@ * along with llmnrd. If not, see <http://www.gnu.org/licenses/>. */ +#define _GNU_SOURCE +#define __APPLE_USE_RFC_3542 #include <errno.h> #include <getopt.h> #include <stdint.h> @@ -26,6 +28,7 @@ #include <arpa/inet.h> #include <net/if.h> +#include <netinet/in.h> #include <sys/select.h> #include <sys/socket.h> #include <sys/time.h> @@ -98,6 +101,7 @@ int main(int argc, char **argv) uint16_t qtype = LLMNR_QTYPE_ANY; bool ipv6 = false; struct pkt *p; + unsigned int ifindex = 0; static const int TTL = 255; while ((c = getopt_long(argc, argv, short_ops, long_opts, NULL)) != -1) { @@ -182,7 +186,7 @@ int main(int argc, char **argv) } if (iface != NULL) { - unsigned int ifindex = if_nametoindex(iface); + ifindex = if_nametoindex(iface); if (ifindex == 0 && errno != 0) { log_err("Could not get interface %s: %s\n", iface, strerror(errno)); @@ -216,6 +220,11 @@ int main(int argc, char **argv) for (i = 0; i < count; i++) { struct llmnr_hdr *hdr; struct sockaddr_storage sst; + socklen_t sst_len; + struct iovec iov[1]; + struct msghdr msg; + struct in6_pktinfo ipi6; + uint8_t c[CMSG_SPACE(sizeof(ipi6))]; size_t query_pkt_len; fd_set rfds; struct timeval tv; @@ -237,8 +246,13 @@ int main(int argc, char **argv) pkt_put_u16(p, htons(LLMNR_QCLASS_IN)); memset(&sst, 0, sizeof(sst)); + memset(&iov, 0, sizeof(iov)); + memset(&msg, 0, sizeof(msg)); + memset(&ipi6, 0, sizeof(ipi6)); + if (ipv6) { struct sockaddr_in6 *sin6 = (struct sockaddr_in6*)&sst; + struct cmsghdr *cmsg; sin6->sin6_family = AF_INET6; sin6->sin6_port = htons(LLMNR_UDP_PORT); @@ -246,6 +260,16 @@ int main(int argc, char **argv) log_err("Failed to convert IPv6 address: %s\n", strerror(errno)); break; } + sst_len = sizeof(*sin6); + + ipi6.ipi6_ifindex = ifindex; + msg.msg_control = c; + msg.msg_controllen = sizeof(c); + cmsg = CMSG_FIRSTHDR(&msg); + cmsg->cmsg_level = IPPROTO_IPV6; + cmsg->cmsg_type = IPV6_PKTINFO; + cmsg->cmsg_len = CMSG_LEN(sizeof(ipi6)); + memcpy(CMSG_DATA(cmsg), &ipi6, sizeof(ipi6)); } else { struct sockaddr_in *sin = (struct sockaddr_in *)&sst; @@ -255,9 +279,17 @@ int main(int argc, char **argv) log_err("Failed to convert IPv4 address: %s\n", strerror(errno)); break; } + sst_len = sizeof(*sin); } - if (sendto(sock, p->data, pkt_len(p), 0, (struct sockaddr *)&sst, sizeof(sst)) < 0) { + iov[0].iov_base = p->data; + iov[0].iov_len = pkt_len(p); + msg.msg_iov = iov; + msg.msg_iovlen = 1; + msg.msg_name = &sst; + msg.msg_namelen = sst_len; + + if (sendmsg(sock, &msg, 0) < 0) { log_err("Failed to send UDP packet: %s\n", strerror(errno)); break; } |