From fe4f24a7296641ee29b56defacb3373ee7692eff Mon Sep 17 00:00:00 2001
From: Erik Ekman <yarrick@kryo.se>
Date: Wed, 11 Jul 2007 18:27:18 +0000
Subject: [PATCH] Store only in_addr, not whole sockaddr, fixes #21

---
 src/iodined.c | 31 ++++++++++++++++++++-----------
 src/user.h    |  3 +--
 2 files changed, 21 insertions(+), 13 deletions(-)

diff --git a/src/iodined.c b/src/iodined.c
index 06fc88d..dd590fd 100644
--- a/src/iodined.c
+++ b/src/iodined.c
@@ -127,10 +127,19 @@ send_version_response(int fd, version_ack_t ack, uint32_t payload, struct user *
 	write_dns(fd, &u->q, out, sizeof(out));
 }
 
+static int
+cmp_remote_ip(int userid, struct query *q) {
+	struct sockaddr_in *tempin;
+
+	tempin = (struct sockaddr_in *) &(q->from);
+	return memcmp(&(users[userid].host), &(tempin->sin_addr), sizeof(struct in_addr));
+}
+
 static int
 tunnel_dns(int tun_fd, int dns_fd)
 {
 	struct in_addr tempip;
+	struct sockaddr_in *tempin;
 	struct user dummy;
 	struct ip *hdr;
 	unsigned long outlen;
@@ -164,9 +173,10 @@ tunnel_dns(int tun_fd, int dns_fd)
 				userid = find_available_user();
 				if (userid >= 0) {
 					users[userid].seed = rand();
-					memcpy(&(users[userid].host), &(dummy.q.from), dummy.q.fromlen);
+					/* Store remote IP number */
+					tempin = (struct sockaddr_in *) &(dummy.q.from);
+					memcpy(&(users[userid].host), &(tempin->sin_addr), sizeof(struct in_addr));
 					memcpy(&(users[userid].q), &(dummy.q), sizeof(struct query));
-					users[userid].addrlen = dummy.q.fromlen;
 					users[userid].encoder = get_base32_encoder();
 					send_version_response(dns_fd, VERSION_ACK, users[userid].seed, &users[userid]);
 					users[userid].q.id = 0;
@@ -191,8 +201,7 @@ tunnel_dns(int tun_fd, int dns_fd)
 		users[userid].last_pkt = time(NULL);
 		login_calculate(logindata, 16, password, users[userid].seed);
 
-		if (dummy.q.fromlen != users[userid].addrlen ||
-				memcmp(&(users[userid].host), &(dummy.q.from), dummy.q.fromlen) != 0) {
+		if (cmp_remote_ip(userid, &(dummy.q)) != 0) {
 			write_dns(dns_fd, &(dummy.q), "BADIP", 5);
 		} else {
 			if (read >= 18 && (memcmp(logindata, unpacked+1, 16) == 0)) {
@@ -223,8 +232,10 @@ tunnel_dns(int tun_fd, int dns_fd)
 			write_dns(dns_fd, &(dummy.q), "BADIP", 5);
 			return 0; /* illegal id */
 		}
-		memcpy(&(users[userid].q), &(dummy.q), sizeof(struct query));
-		users[userid].last_pkt = time(NULL);
+		if (cmp_remote_ip(userid, &(dummy.q)) != 0) {
+			memcpy(&(users[userid].q), &(dummy.q), sizeof(struct query));
+			users[userid].last_pkt = time(NULL);
+		}
 	} else if((in[0] >= '0' && in[0] <= '9')
 			|| (in[0] >= 'a' && in[0] <= 'f')
 			|| (in[0] >= 'A' && in[0] <= 'F')) {
@@ -242,8 +253,7 @@ tunnel_dns(int tun_fd, int dns_fd)
 		}
 
 		/* Check sending ip number */
-		if (dummy.q.fromlen != users[userid].addrlen ||
-				memcmp(&(users[userid].host), &(dummy.q.from), dummy.q.fromlen) != 0) {
+		if (cmp_remote_ip(userid, &(dummy.q)) != 0) {
 			write_dns(dns_fd, &(dummy.q), "BADIP", 5);
 		} else {
 			/* decode with this users encoding */
@@ -252,7 +262,6 @@ tunnel_dns(int tun_fd, int dns_fd)
 
 			users[userid].last_pkt = time(NULL);
 			memcpy(&(users[userid].q), &(dummy.q), sizeof(struct query));
-			users[userid].addrlen = dummy.q.fromlen;
 			memcpy(users[userid].inpacket.data + users[userid].inpacket.offset, unpacked, read);
 			users[userid].inpacket.len += read;
 			users[userid].inpacket.offset += read;
@@ -281,8 +290,8 @@ tunnel_dns(int tun_fd, int dns_fd)
 		}
 	}
 	/* userid must be set for a reply to be sent */
-	if (userid >= 0 && userid < USERS && dummy.q.fromlen == users[userid].addrlen &&
-			memcmp(&(users[userid].host), &(dummy.q.from), dummy.q.fromlen) == 0 &&
+	if (userid >= 0 && userid < USERS && 
+			cmp_remote_ip(userid, &(dummy.q)) != 0 &&
 			users[userid].outpacket.len > 0) {
 
 		write_dns(dns_fd, &(dummy.q), users[userid].outpacket.data, users[userid].outpacket.len);
diff --git a/src/user.h b/src/user.h
index 2d0d2ad..b333bcb 100644
--- a/src/user.h
+++ b/src/user.h
@@ -25,8 +25,7 @@ struct user {
 	time_t last_pkt;
 	int seed;
 	in_addr_t tun_ip;
-	struct sockaddr host;
-	int addrlen;
+	struct in_addr host;
 	struct query q;
 	struct packet inpacket;
 	struct packet outpacket;