Compute CRC32C also when using the loopback interface.

This fixes #327.
diff --git a/programs/chargen_server_upcall.c b/programs/chargen_server_upcall.c
index 9111a06..20c5a8f 100644
--- a/programs/chargen_server_upcall.c
+++ b/programs/chargen_server_upcall.c
@@ -167,6 +167,7 @@
 	usrsctp_sysctl_set_sctp_debug_on(SCTP_DEBUG_NONE);
 #endif
 	usrsctp_sysctl_set_sctp_blackhole(2);
+	usrsctp_sysctl_set_sctp_no_csum_on_loopback(0);
 
 	if ((listening_socket = usrsctp_socket(AF_INET6, SOCK_STREAM, IPPROTO_SCTP, NULL, NULL, 0, NULL)) == NULL) {
 		perror("usrsctp_socket");
diff --git a/programs/client.c b/programs/client.c
index 5dac2f4..578a787 100644
--- a/programs/client.c
+++ b/programs/client.c
@@ -115,6 +115,8 @@
 	usrsctp_sysctl_set_sctp_debug_on(SCTP_DEBUG_NONE);
 #endif
 	usrsctp_sysctl_set_sctp_blackhole(2);
+	usrsctp_sysctl_set_sctp_no_csum_on_loopback(0);
+
 	if ((sock = usrsctp_socket(AF_INET6, SOCK_STREAM, IPPROTO_SCTP, receive_cb, NULL, 0, NULL)) == NULL) {
 		perror("usrsctp_socket");
 	}
diff --git a/programs/client_upcall.c b/programs/client_upcall.c
index 3de0783..b7b25f6 100644
--- a/programs/client_upcall.c
+++ b/programs/client_upcall.c
@@ -150,6 +150,8 @@
 	usrsctp_sysctl_set_sctp_debug_on(SCTP_DEBUG_NONE);
 #endif
 	usrsctp_sysctl_set_sctp_blackhole(2);
+	usrsctp_sysctl_set_sctp_no_csum_on_loopback(0);
+
 	if ((sock = usrsctp_socket(AF_INET6, SOCK_STREAM, IPPROTO_SCTP, NULL, NULL, 0, NULL)) == NULL) {
 		perror("usrsctp_socket");
 		exit(1);
diff --git a/programs/daytime_server.c b/programs/daytime_server.c
index 38f523e..3047558 100644
--- a/programs/daytime_server.c
+++ b/programs/daytime_server.c
@@ -78,6 +78,7 @@
 	usrsctp_sysctl_set_sctp_debug_on(SCTP_DEBUG_NONE);
 #endif
 	usrsctp_sysctl_set_sctp_blackhole(2);
+	usrsctp_sysctl_set_sctp_no_csum_on_loopback(0);
 
 	if ((sock = usrsctp_socket(AF_INET, SOCK_STREAM, IPPROTO_SCTP, NULL, NULL, 0, NULL)) == NULL) {
 		perror("usrsctp_socket");
diff --git a/programs/daytime_server_upcall.c b/programs/daytime_server_upcall.c
index af71383..522f3f1 100644
--- a/programs/daytime_server_upcall.c
+++ b/programs/daytime_server_upcall.c
@@ -99,6 +99,7 @@
 	usrsctp_sysctl_set_sctp_debug_on(SCTP_DEBUG_NONE);
 #endif
 	usrsctp_sysctl_set_sctp_blackhole(2);
+	usrsctp_sysctl_set_sctp_no_csum_on_loopback(0);
 
 	if ((sock = usrsctp_socket(AF_INET, SOCK_STREAM, IPPROTO_SCTP, NULL, NULL, 0, NULL)) == NULL) {
 		perror("usrsctp_socket");
diff --git a/programs/discard_server.c b/programs/discard_server.c
index d26d2b5..5584247 100644
--- a/programs/discard_server.c
+++ b/programs/discard_server.c
@@ -147,6 +147,7 @@
 	usrsctp_sysctl_set_sctp_debug_on(SCTP_DEBUG_ALL);
 #endif
 	usrsctp_sysctl_set_sctp_blackhole(2);
+	usrsctp_sysctl_set_sctp_no_csum_on_loopback(0);
 
 	if ((sock = usrsctp_socket(AF_INET6, SOCK_SEQPACKET, IPPROTO_SCTP, use_cb?receive_cb:NULL, NULL, 0, NULL)) == NULL) {
 		perror("usrsctp_socket");
diff --git a/programs/discard_server_upcall.c b/programs/discard_server_upcall.c
index 51f50d4..986a950 100644
--- a/programs/discard_server_upcall.c
+++ b/programs/discard_server_upcall.c
@@ -163,6 +163,7 @@
 	usrsctp_sysctl_set_sctp_debug_on(SCTP_DEBUG_NONE);
 #endif
 	usrsctp_sysctl_set_sctp_blackhole(2);
+	usrsctp_sysctl_set_sctp_no_csum_on_loopback(0);
 
 	if ((sock = usrsctp_socket(AF_INET6, SOCK_SEQPACKET, IPPROTO_SCTP, NULL, NULL, 0, NULL)) == NULL) {
 		perror("usrsctp_socket");
diff --git a/programs/echo_server.c b/programs/echo_server.c
index 583a308..4b4a3e5 100644
--- a/programs/echo_server.c
+++ b/programs/echo_server.c
@@ -162,6 +162,7 @@
 	usrsctp_sysctl_set_sctp_debug_on(SCTP_DEBUG_NONE);
 #endif
 	usrsctp_sysctl_set_sctp_blackhole(2);
+	usrsctp_sysctl_set_sctp_no_csum_on_loopback(0);
 
 	if ((sock = usrsctp_socket(AF_INET6, SOCK_SEQPACKET, IPPROTO_SCTP, use_cb?receive_cb:NULL, NULL, 0, NULL)) == NULL) {
 		perror("usrsctp_socket");
diff --git a/programs/echo_server_upcall.c b/programs/echo_server_upcall.c
index 7a594fa..4c966cd 100644
--- a/programs/echo_server_upcall.c
+++ b/programs/echo_server_upcall.c
@@ -180,6 +180,7 @@
 	usrsctp_sysctl_set_sctp_debug_on(SCTP_DEBUG_NONE);
 #endif
 	usrsctp_sysctl_set_sctp_blackhole(2);
+	usrsctp_sysctl_set_sctp_no_csum_on_loopback(0);
 
 	if ((sock = usrsctp_socket(AF_INET6, SOCK_SEQPACKET, IPPROTO_SCTP, NULL, NULL, 0, NULL)) == NULL) {
 		perror("usrsctp_socket");
diff --git a/programs/http_client.c b/programs/http_client.c
index c374812..ca14c89 100644
--- a/programs/http_client.c
+++ b/programs/http_client.c
@@ -169,6 +169,7 @@
 #endif
 
 	usrsctp_sysctl_set_sctp_blackhole(2);
+	usrsctp_sysctl_set_sctp_no_csum_on_loopback(0);
 
 	if ((sock = usrsctp_socket(address_family, SOCK_STREAM, IPPROTO_SCTP, receive_cb, NULL, 0, NULL)) == NULL) {
 		perror("usrsctp_socket");
diff --git a/programs/http_client_upcall.c b/programs/http_client_upcall.c
index 0220d25..e2c0503 100644
--- a/programs/http_client_upcall.c
+++ b/programs/http_client_upcall.c
@@ -197,6 +197,7 @@
 #endif
 
 	usrsctp_sysctl_set_sctp_blackhole(2);
+	usrsctp_sysctl_set_sctp_no_csum_on_loopback(0);
 
 	if ((sock = usrsctp_socket(address_family, SOCK_STREAM, IPPROTO_SCTP, NULL, NULL, 0, NULL)) == NULL) {
 		perror("usrsctp_socket");
diff --git a/programs/rtcweb.c b/programs/rtcweb.c
index 01470ad..720aef9 100644
--- a/programs/rtcweb.c
+++ b/programs/rtcweb.c
@@ -1336,6 +1336,7 @@
 	usrsctp_sysctl_set_sctp_debug_on(SCTP_DEBUG_NONE);
 #endif
 	usrsctp_sysctl_set_sctp_blackhole(2);
+	usrsctp_sysctl_set_sctp_no_csum_on_loopback(0);
 
 	if ((sock = usrsctp_socket(AF_INET, SOCK_STREAM, IPPROTO_SCTP, receive_cb, NULL, 0, &peer_connection)) == NULL) {
 		perror("socket");
diff --git a/programs/tsctp.c b/programs/tsctp.c
index d7c23e4..94c2a0a 100644
--- a/programs/tsctp.c
+++ b/programs/tsctp.c
@@ -569,6 +569,7 @@
 	usrsctp_sysctl_set_sctp_debug_on(SCTP_DEBUG_ALL);
 #endif
 	usrsctp_sysctl_set_sctp_blackhole(2);
+	usrsctp_sysctl_set_sctp_no_csum_on_loopback(0);
 	usrsctp_sysctl_set_sctp_enable_sack_immediately(1);
 
 	if (client) {
diff --git a/programs/tsctp_upcall.c b/programs/tsctp_upcall.c
index 16b589a..16676c3 100644
--- a/programs/tsctp_upcall.c
+++ b/programs/tsctp_upcall.c
@@ -627,6 +627,7 @@
 	usrsctp_sysctl_set_sctp_debug_on(SCTP_DEBUG_ALL);
 #endif
 	usrsctp_sysctl_set_sctp_blackhole(2);
+	usrsctp_sysctl_set_sctp_no_csum_on_loopback(0);
 	usrsctp_sysctl_set_sctp_enable_sack_immediately(1);
 
 	if (!(psock = usrsctp_socket(AF_INET, SOCK_STREAM, IPPROTO_SCTP, NULL, NULL, 0, NULL))) {