Out-of-order data chunks handling and more

This patch addresses the need to handle out-of-order data chunks
received by a peer. To do that effectively, we had to add the handling
of data chunks flags (E/B/U bit) to understand whether the stream is
fragmenting user-message data and in that case if a fragment is the
FIRST/MIDDLE/LAST one of a transmission.
The same patch also addresses the security requirement to have a HMAC
calculated and incorporated in the INIT_ACK and COOKIE_ECHO chunks. The
algorithm used is the HMAC-SHA1.

Change-Id: Ib6a9a80492e2aafe5c8480d6e02da895efe9f90b
Signed-off-by: Marco Varlese <marco.varlese@suse.com>

1 files changed, 57 insertions, 47 deletions

diff --git a/src/vnet/sctp/sctp_packet.h b/src/vnet/sctp/sctp_packet.h
index d1fe7ab71ea..b831d249f76 100644
--- a/src/vnet/sctp/sctp_packet.h
+++ b/src/vnet/sctp/sctp_packet.h
@@ -267,6 +267,15 @@ typedef struct
 #define CHUNK_FLAGS_MASK 0x00FF0000
 #define CHUNK_FLAGS_SHIFT 16
 
+#define CHUNK_UBIT_MASK 0x000F0000
+#define CHUNK_UBIT_SHIFT 18
+
+#define CHUNK_BBIT_MASK 0x000F0000
+#define CHUNK_BBIT_SHIFT 17
+
+#define CHUNK_EBIT_MASK 0x000F0000
+#define CHUNK_EBIT_SHIFT 16
+
 #define CHUNK_LENGTH_MASK 0x0000FFFF
 #define CHUNK_LENGTH_SHIFT 0
 
@@ -283,6 +292,45 @@ vnet_sctp_common_hdr_params_net_to_host (sctp_chunks_common_hdr_t * h)
 }
 
 always_inline void
+vnet_sctp_set_ubit (sctp_chunks_common_hdr_t * h)
+{
+  h->params &= ~(CHUNK_UBIT_MASK);
+  h->params |= (1 << CHUNK_UBIT_SHIFT) & CHUNK_UBIT_MASK;
+}
+
+always_inline u8
+vnet_sctp_get_ubit (sctp_chunks_common_hdr_t * h)
+{
+  return ((h->params & CHUNK_UBIT_MASK) >> CHUNK_UBIT_SHIFT);
+}
+
+always_inline void
+vnet_sctp_set_bbit (sctp_chunks_common_hdr_t * h)
+{
+  h->params &= ~(CHUNK_BBIT_MASK);
+  h->params |= (1 << CHUNK_BBIT_SHIFT) & CHUNK_BBIT_MASK;
+}
+
+always_inline u8
+vnet_sctp_get_bbit (sctp_chunks_common_hdr_t * h)
+{
+  return ((h->params & CHUNK_BBIT_MASK) >> CHUNK_BBIT_SHIFT);
+}
+
+always_inline void
+vnet_sctp_set_ebit (sctp_chunks_common_hdr_t * h)
+{
+  h->params &= ~(CHUNK_EBIT_MASK);
+  h->params |= (1 << CHUNK_EBIT_SHIFT) & CHUNK_EBIT_MASK;
+}
+
+always_inline u8
+vnet_sctp_get_ebit (sctp_chunks_common_hdr_t * h)
+{
+  return ((h->params & CHUNK_EBIT_MASK) >> CHUNK_EBIT_SHIFT);
+}
+
+always_inline void
 vnet_sctp_set_chunk_type (sctp_chunks_common_hdr_t * h, sctp_chunk_type t)
 {
   h->params &= ~(CHUNK_TYPE_MASK);
@@ -408,45 +456,6 @@ typedef struct
 } sctp_payload_data_chunk_t;
 
 always_inline void
-vnet_sctp_set_ebit (sctp_payload_data_chunk_t * p, u8 enable)
-{
-  //p->chunk_hdr.flags = clib_host_to_net_u16 (enable);
-}
-
-always_inline u8
-vnet_sctp_get_ebit (sctp_payload_data_chunk_t * p)
-{
-  //return (clib_net_to_host_u16 (p->chunk_hdr.flags));
-  return 0;
-}
-
-always_inline void
-vnet_sctp_set_bbit (sctp_payload_data_chunk_t * p, u8 enable)
-{
-  //p->chunk_hdr.flags = clib_host_to_net_u16 (enable << 1);
-}
-
-always_inline u8
-vnet_sctp_get_bbit (sctp_payload_data_chunk_t * p)
-{
-  //return (clib_net_to_host_u16 (p->chunk_hdr.flags >> 1));
-  return 0;
-}
-
-always_inline void
-vnet_sctp_set_ubit (sctp_payload_data_chunk_t * p, u8 enable)
-{
-  //p->chunk_hdr.flags = clib_host_to_net_u16 (enable << 2);
-}
-
-always_inline u8
-vnet_sctp_get_ubit (sctp_payload_data_chunk_t * p)
-{
-  //return (clib_net_to_host_u16 (p->chunk_hdr.flags >> 2));
-  return 0;
-}
-
-always_inline void
 vnet_sctp_set_tsn (sctp_payload_data_chunk_t * p, u32 tsn)
 {
   p->tsn = clib_host_to_net_u32 (tsn);
@@ -680,6 +689,14 @@ typedef struct
  */
 typedef sctp_init_chunk_t sctp_init_ack_chunk_t;
 
+typedef struct
+{
+  u16 type;
+  u16 length;
+
+} sctp_opt_params_hdr_t;
+
+#define SHA1_OUTPUT_LENGTH 20
 /*
  * 0                   1                   2                   3
  * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
@@ -693,16 +710,9 @@ typedef sctp_init_chunk_t sctp_init_ack_chunk_t;
  */
 typedef struct
 {
-  u16 type;
-  u16 length;
-
-} sctp_opt_params_hdr_t;
-
-typedef struct
-{
   sctp_opt_params_hdr_t param_hdr;
 
-  u64 mac;			/* RFC 2104 */
+  unsigned char mac[SHA1_OUTPUT_LENGTH];	/* RFC 2104 */
   u32 creation_time;
   u32 cookie_lifespan;