Fixed issue to pass PSK identity hint to application in callback

In cases (with PSK ciphersuite) where Server is sending
'PSK Identity Hint’ inside ServerKeyExchange message, DTLS library
is not passing the ‘identity hint’ inside ‘desc’ argument in
get_psk_info(DTLS_PSK_KEY, desc) callback. Instead, ‘desc’ contains
the identity of the client itself. The reason for this is that the
code inside dtls_send_client_key_exchange() method
overwrites the ‘identity hint’ received earlier.

Change-Id: Ibf447e3a6b33284118908a52aed4cf636038ab23
Signed-off-by: Sachin Agrawal <sachin.agrawal@intel.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/119
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Sakthivel Samidurai <sakthivel.samidurai@intel.com>
Reviewed-by: Sashi Penta <sashi.kumar.penta@intel.com>
Reviewed-by: Sudarshan Prasad <sudarshan.prasad@intel.com>

diff --git a/extlibs/tinydtls/0001-Fixed-issue-to-pass-PSK-identity-hint-to-application.patch b/extlibs/tinydtls/0001-Fixed-issue-to-pass-PSK-identity-hint-to-application.patch
new file mode 100644 (file)
index 0000000..343c891
--- /dev/null
+++ b/extlibs/tinydtls/0001-Fixed-issue-to-pass-PSK-identity-hint-to-application.patch
@@ -0,0 +1,73 @@
+From 116451f8fab0df90e87d394d1fa1ac9e739c7dbe Mon Sep 17 00:00:00 2001
+From: Sachin Agrawal <sachin.agrawal@intel.com>
+Date: Tue, 20 Jan 2015 15:57:40 -0800
+Subject: [PATCH 1/1] Fixed issue to pass PSK identity hint to application in
+ callback
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+In cases (with PSK ciphersuite) where Server is sending
+'PSK Identity Hint’ inside ServerKeyExchange message, DTLS library
+is not passing the ‘identity hint’ inside ‘desc’ argument in
+get_psk_info(DTLS_PSK_KEY, desc) callback. Instead, ‘desc’ contains
+the identity of the client itself. The reason for this is that the
+code inside dtls_send_client_key_exchange() method
+overwrites the ‘identity hint’ received earlier.
+
+Change-Id: Ibf447e3a6b33284118908a52aed4cf636038ab23
+Signed-off-by: Sachin Agrawal <sachin.agrawal@intel.com>
+---
+ extlibs/tinydtls/dtls.c |   17 +++++++----------
+ 1 file changed, 7 insertions(+), 10 deletions(-)
+
+diff --git a/extlibs/tinydtls/dtls.c b/extlibs/tinydtls/dtls.c
+index 92222eb..9090f22 100644
+--- a/extlibs/tinydtls/dtls.c
++++ b/extlibs/tinydtls/dtls.c
+@@ -2164,6 +2164,7 @@ static int
+ dtls_send_client_key_exchange(dtls_context_t *ctx, dtls_peer_t *peer)
+ {
+   uint8 buf[DTLS_CKXEC_LENGTH];
++  uint8 client_id[DTLS_PSK_MAX_CLIENT_IDENTITY_LEN];
+   uint8 *p;
+   dtls_handshake_parameters_t *handshake = peer->handshake_params;
+ 
+@@ -2175,28 +2176,24 @@ dtls_send_client_key_exchange(dtls_context_t *ctx, dtls_peer_t *peer)
+     int len;
+ 
+     len = CALL(ctx, get_psk_info, &peer->session, DTLS_PSK_IDENTITY,
+-             handshake->keyx.psk.identity, handshake->keyx.psk.id_length,
+-             buf + sizeof(uint16),
+-             min(sizeof(buf) - sizeof(uint16),
+-                 sizeof(handshake->keyx.psk.identity)));
++               NULL, 0,
++               client_id,
++               sizeof(client_id));
+     if (len < 0) {
+       dtls_crit("no psk identity set in kx\n");
+       return len;
+     }
+ 
+     if (len + sizeof(uint16) > DTLS_CKXEC_LENGTH) {
+-      memset(&handshake->keyx.psk, 0, sizeof(dtls_handshake_parameters_psk_t));
+       dtls_warn("the psk identity is too long\n");
+       return dtls_alert_fatal_create(DTLS_ALERT_INTERNAL_ERROR);
+     }
+-    handshake->keyx.psk.id_length = (unsigned int)len;
+-    memcpy(handshake->keyx.psk.identity, p + sizeof(uint16), len);
+ 
+-    dtls_int_to_uint16(p, handshake->keyx.psk.id_length);
++    dtls_int_to_uint16(p, len);
+     p += sizeof(uint16);
+ 
+-    memcpy(p, handshake->keyx.psk.identity, handshake->keyx.psk.id_length);
+-    p += handshake->keyx.psk.id_length;
++    memcpy(p, client_id, len);
++    p += len;
+ 
+     break;
+   }
+-- 
+1.7.9.5
+

diff --git a/extlibs/tinydtls/dtls.c b/extlibs/tinydtls/dtls.c
index 92222eb..9090f22 100644 (file)
--- a/extlibs/tinydtls/dtls.c
+++ b/extlibs/tinydtls/dtls.c
@@ -2164,6 +2164,7 @@ static int
 dtls_send_client_key_exchange(dtls_context_t *ctx, dtls_peer_t *peer)
 {
   uint8 buf[DTLS_CKXEC_LENGTH];
+  uint8 client_id[DTLS_PSK_MAX_CLIENT_IDENTITY_LEN];
   uint8 *p;
   dtls_handshake_parameters_t *handshake = peer->handshake_params;
 
@@ -2175,28 +2176,24 @@ dtls_send_client_key_exchange(dtls_context_t *ctx, dtls_peer_t *peer)
     int len;
 
     len = CALL(ctx, get_psk_info, &peer->session, DTLS_PSK_IDENTITY,
-              handshake->keyx.psk.identity, handshake->keyx.psk.id_length,
-              buf + sizeof(uint16),
-              min(sizeof(buf) - sizeof(uint16),
-                  sizeof(handshake->keyx.psk.identity)));
+               NULL, 0,
+               client_id,
+               sizeof(client_id));
     if (len < 0) {
       dtls_crit("no psk identity set in kx\n");
       return len;
     }
 
     if (len + sizeof(uint16) > DTLS_CKXEC_LENGTH) {
-      memset(&handshake->keyx.psk, 0, sizeof(dtls_handshake_parameters_psk_t));
       dtls_warn("the psk identity is too long\n");
       return dtls_alert_fatal_create(DTLS_ALERT_INTERNAL_ERROR);
     }
-    handshake->keyx.psk.id_length = (unsigned int)len;
-    memcpy(handshake->keyx.psk.identity, p + sizeof(uint16), len);
 
-    dtls_int_to_uint16(p, handshake->keyx.psk.id_length);
+    dtls_int_to_uint16(p, len);
     p += sizeof(uint16);
 
-    memcpy(p, handshake->keyx.psk.identity, handshake->keyx.psk.id_length);
-    p += handshake->keyx.psk.id_length;
+    memcpy(p, client_id, len);
+    p += len;
 
     break;
   }