From a96e2e7a693fb04479ef94c6c9f690053ca56c68 Mon Sep 17 00:00:00 2001
From: Masaq- <tilt@techie.com>
Date: Sat, 22 Oct 2016 04:46:48 +0000
Subject: [PATCH] Refuse attempts to set options after option negotiation has
completed.
---
src/iodined.c | 20 +++++++++++++++++---
src/user.c | 2 ++
src/user.h | 1 +
3 files changed, 20 insertions(+), 3 deletions(-)
diff --git a/src/iodined.c b/src/iodined.c
index 2e6f7bf..608d84e 100644
--- a/src/iodined.c
+++ b/src/iodined.c
@@ -263,6 +263,19 @@ check_authenticated_user_and_ip(int userid, struct query *q)
return 0;
}
+static int
+check_authenticated_user_and_ip_and_options(int userid, struct query *q)
+{
+ int res = check_authenticated_user_and_ip(userid, q);
+ if (res || check_ip)
+ return res;
+
+ if (users[userid].options_locked)
+ return 1;
+
+ return 0;
+}
+
static void
send_raw(int fd, char *buf, int buflen, int user, int cmd, struct query *q)
{
@@ -973,7 +986,7 @@ handle_null_request(int tun_fd, int dns_fd, struct dnsfd *dns_fds, struct query
userid = b32_8to5(in[1]);
- if (check_authenticated_user_and_ip(userid, q) != 0) {
+ if (check_authenticated_user_and_ip_and_options(userid, q) != 0) {
write_dns(dns_fd, q, "BADIP", 5, 'T');
return; /* illegal id */
}
@@ -1014,7 +1027,7 @@ handle_null_request(int tun_fd, int dns_fd, struct dnsfd *dns_fds, struct query
userid = b32_8to5(in[1]);
- if (check_authenticated_user_and_ip(userid, q) != 0) {
+ if (check_authenticated_user_and_ip_and_options(userid, q) != 0) {
write_dns(dns_fd, q, "BADIP", 5, 'T');
return; /* illegal id */
}
@@ -1177,7 +1190,7 @@ handle_null_request(int tun_fd, int dns_fd, struct dnsfd *dns_fds, struct query
/* Downstream fragsize packet */
userid = unpacked[0];
- if (check_authenticated_user_and_ip(userid, q) != 0) {
+ if (check_authenticated_user_and_ip_and_options(userid, q) != 0) {
write_dns(dns_fd, q, "BADIP", 5, 'T');
return; /* illegal id */
}
@@ -1187,6 +1200,7 @@ handle_null_request(int tun_fd, int dns_fd, struct dnsfd *dns_fds, struct query
write_dns(dns_fd, q, "BADFRAG", 7, users[userid].downenc);
} else {
users[userid].fragsize = max_frag_size;
+ users[userid].options_locked = 1;
write_dns(dns_fd, q, &unpacked[1], 2, users[userid].downenc);
}
return;
diff --git a/src/user.c b/src/user.c
index ce1fa5a..c977d8e 100644
--- a/src/user.c
+++ b/src/user.c
@@ -77,6 +77,7 @@ init_users(in_addr_t my_ip, int netbits)
users[i].disabled = 0;
users[i].authenticated = 0;
users[i].authenticated_raw = 0;
+ users[i].options_locked = 0;
users[i].active = 0;
/* Rest is reset on login ('V' packet) */
}
@@ -156,6 +157,7 @@ find_available_user()
users[i].active = 1;
users[i].authenticated = 0;
users[i].authenticated_raw = 0;
+ users[i].options_locked = 0;
users[i].last_pkt = time(NULL);
users[i].fragsize = 4096;
users[i].conn = CONN_DNS_NULL;
diff --git a/src/user.h b/src/user.h
index 7d2553a..a8bdf2f 100644
--- a/src/user.h
+++ b/src/user.h
@@ -39,6 +39,7 @@ struct tun_user {
int active;
int authenticated;
int authenticated_raw;
+ int options_locked;
int disabled;
time_t last_pkt;
int seed;