X-Git-Url: http://git.openwrt.org/?a=blobdiff_plain;f=dns.c;h=cf8c3d5bc3f93842f83df316858035167b54932d;hb=b424a3b9941e2818f632a92bdbc8f5e5d16a2457;hp=75e739dbfa63d88ecf7a0f5f47059831f0331317;hpb=00129b08c5e5df7639119cac812c765736a4c7c1;p=project%2Fmdnsd.git

diff --git a/dns.c b/dns.c
index 75e739d..cf8c3d5 100644
--- a/dns.c
+++ b/dns.c
@@ -36,8 +36,8 @@
 #include "util.h"
 #include "dns.h"
 
-char *rdata_buffer;
-static char *name_buffer;
+char rdata_buffer[MAX_DATA_LEN + 1];
+static char name_buffer[MAX_NAME_LEN + 1];
 
 const char*
 dns_type_string(uint16_t type)
@@ -65,11 +65,43 @@ dns_type_string(uint16_t type)
 	return "N/A";
 }
 
+static int
+dns_send_packet(int fd, struct iovec *iov, int iov_len)
+{
+	static size_t cmsg_data[( CMSG_SPACE(sizeof(struct in_pktinfo)) / sizeof(size_t)) + 1];
+	static struct sockaddr_in a = {
+		.sin_family = AF_INET,
+		.sin_port = htons(MCAST_PORT),
+	};
+	static struct msghdr m = {
+		.msg_name = (struct sockaddr *) &a,
+		.msg_namelen = sizeof(a),
+		.msg_control = cmsg_data,
+		.msg_controllen = CMSG_LEN(sizeof(struct in_pktinfo)),
+	};
+	struct in_pktinfo *pkti;
+	struct cmsghdr *cmsg;
+
+	m.msg_iov = iov;
+	m.msg_iovlen = iov_len;
+
+	memset(cmsg_data, 0, sizeof(cmsg_data));
+	cmsg = CMSG_FIRSTHDR(&m);
+	cmsg->cmsg_len = m.msg_controllen;
+	cmsg->cmsg_level = IPPROTO_IP;
+	cmsg->cmsg_type = IP_PKTINFO;
+
+	pkti = (struct in_pktinfo*) CMSG_DATA(cmsg);
+	pkti->ipi_ifindex = iface_index;
+
+	a.sin_addr.s_addr = inet_addr(MCAST_ADDR);
+
+	return sendmsg(fd, &m, 0);
+}
+
 void
 dns_send_question(struct uloop_fd *u, char *question, int type)
 {
-	static size_t cmsg_data[( CMSG_SPACE(sizeof(struct in_pktinfo)) / sizeof(size_t)) + 1];
-	static unsigned char buffer[MAX_NAME_LEN];
 	static struct dns_header h = {
 		.questions = cpu_to_be16(1),
 	};
@@ -82,49 +114,24 @@ dns_send_question(struct uloop_fd *u, char *question, int type)
 			.iov_len = sizeof(h),
 		},
 		{
-			.iov_base = buffer,
+			.iov_base = name_buffer,
 		},
 		{
 			.iov_base = &q,
 			.iov_len = sizeof(q),
 		}
 	};
-	static struct sockaddr_in a = {
-		.sin_family = AF_INET,
-		.sin_port = htons(MCAST_PORT),
-	};
-	static struct msghdr m = {
-		.msg_name = (struct sockaddr *) &a,
-		.msg_namelen = sizeof(a),
-		.msg_iov = iov,
-		.msg_iovlen = ARRAY_SIZE(iov),
-		.msg_control = cmsg_data,
-		.msg_controllen = CMSG_LEN(sizeof(struct in_pktinfo)),
-	};
-	struct in_pktinfo *pkti;
-	struct cmsghdr *cmsg;
 	int len;
 
-	a.sin_addr.s_addr = inet_addr(MCAST_ADDR);
 	q.type = __cpu_to_be16(type);
 
-	len = dn_comp(question, buffer, MAX_NAME_LEN, NULL, NULL);
+	len = dn_comp(question, (void *) name_buffer, sizeof(name_buffer), NULL, NULL);
 	if (len < 1)
 		return;
 
 	iov[1].iov_len = len;
 
-	memset(cmsg_data, 0, sizeof(cmsg_data));
-
-	cmsg = CMSG_FIRSTHDR(&m);
-	cmsg->cmsg_len = m.msg_controllen;
-	cmsg->cmsg_level = IPPROTO_IP;
-	cmsg->cmsg_type = IP_PKTINFO;
-
-	pkti = (struct in_pktinfo*) CMSG_DATA(cmsg);
-	pkti->ipi_ifindex = iface_index;
-
-	if (sendmsg(u->fd, &m, 0) < 0)
+	if (dns_send_packet(u->fd, iov, ARRAY_SIZE(iov)) < 0)
 		fprintf(stderr, "failed to send question\n");
 	else
 		DBG(1, "Q <- %s %s\n", dns_type_string(type), question);
@@ -166,30 +173,16 @@ dns_send_answer(struct uloop_fd *u, char *answer)
 {
 	uint8_t buffer[256];
 	struct dns_header h = { 0 };
-	struct msghdr m = { 0 };
 	struct iovec *iov;
-	struct sockaddr_in in = { 0 };
 	int len, i;
 
 	if (!dns_answer_cnt)
 		return;
 
-	in.sin_family = AF_INET;
-	in.sin_addr.s_addr = inet_addr(MCAST_ADDR);
-	in.sin_port = htons(MCAST_PORT);
-
 	h.answers = __cpu_to_be16(dns_answer_cnt);
 	h.flags = __cpu_to_be16(0x8400);
 
-	iov = malloc(sizeof(struct iovec) * ((dns_answer_cnt * 3) + 1));
-	if (!iov)
-		return;
-
-	m.msg_name = &in;
-	m.msg_namelen = sizeof(struct sockaddr_in);
-	m.msg_iov = iov;
-	m.msg_iovlen = (dns_answer_cnt * 3) + 1;
-
+	iov = alloca(sizeof(struct iovec) * ((dns_answer_cnt * 3) + 1));
 	iov[0].iov_base = &h;
 	iov[0].iov_len = sizeof(struct dns_header);
 
@@ -219,7 +212,7 @@ dns_send_answer(struct uloop_fd *u, char *answer)
 		DBG(1, "A <- %s %s\n", dns_type_string(dns_reply[i].type), answer);
 	}
 
-	if (sendmsg(u->fd, &m, 0) < 0)
+	if (dns_send_packet(u->fd, iov, (dns_answer_cnt * 3) + 1) < 0)
 		fprintf(stderr, "failed to send question\n");
 
 	for (i = 0; i < dns_answer_cnt; i++) {
@@ -330,25 +323,3 @@ dns_consume_name(uint8_t *base, int blen, uint8_t **data, int *len)
 
 	return name_buffer;
 }
-
-int
-dns_init(void)
-{
-	name_buffer = malloc(MAX_NAME_LEN + 1);
-	rdata_buffer = malloc(MAX_DATA_LEN + 1);
-
-	if (!name_buffer || !rdata_buffer)
-		return -1;
-
-	memset(name_buffer, 0, MAX_NAME_LEN + 1);
-	memset(rdata_buffer, 0, MAX_NAME_LEN + 1);
-
-	return 0;
-}
-
-void
-dns_cleanup(void)
-{
-	free(name_buffer);
-	free(rdata_buffer);
-}