Merge pull request #9485 from miri64/gnrc_sixlowpan_iphc/enh/i8511-send

gnrc_sixlowpan_iphc: refactor sending for #8511

sys/include/net/gnrc/sixlowpan/internal.h

@@ -18,7 +18,10 @@
 #ifndef NET_GNRC_SIXLOWPAN_INTERNAL_H
 #define NET_GNRC_SIXLOWPAN_INTERNAL_H
 
+#include <stddef.h>
+
 #include "net/gnrc/pkt.h"
+#include "net/gnrc/netif.h"
 
 #ifdef __cplusplus
 extern "C" {
@@ -44,6 +47,24 @@ void gnrc_sixlowpan_dispatch_recv(gnrc_pktsnip_t *pkt, void *context,
 void gnrc_sixlowpan_dispatch_send(gnrc_pktsnip_t *pkt, void *context,
                                   unsigned page);
 
+
+/**
+ * @brief   Checks if packet fits over interface (and fragments if @ref
+ *          net_gnrc_sixlowpan_frag is available and required)
+ *
+ * @param[in] pkt                   The packet to fit. Must not be NULL.
+ * @param[in] orig_datagram_size    The original (uncompressed) datagram size.
+ *                                  Must be greater or equal to the length of
+ *                                  @p pkt as of `pkt->next` (i.e. without
+ *                                  the @ref gnrc_netif_hdr_t).
+ * @param[in] netif                 The interface to fit @p pkt over. Must not
+ *                                  be NULL.
+ * @param[in] page                  Current 6Lo dispatch parsing page
+ */
+void gnrc_sixlowpan_multiplex_by_size(gnrc_pktsnip_t *pkt,
+                                      size_t orig_datagram_size,
+                                      gnrc_netif_t *netif,
+                                      unsigned page);
 #ifdef __cplusplus
 }
 #endif

sys/include/net/gnrc/sixlowpan/iphc.h

@@ -53,13 +53,15 @@ size_t gnrc_sixlowpan_iphc_decode(gnrc_pktsnip_t **dec_hdr, gnrc_pktsnip_t *pkt,
 /**
  * @brief   Compresses a 6LoWPAN for IPHC.
  *
- * @param[in,out] pkt   A 6LoWPAN frame with an uncompressed IPv6 header to
+ * @pre (pkt != NULL)
- *                      send. Will be translated to an 6LoWPAN IPHC frame.
+ *
+ * @param[in] pkt   A 6LoWPAN frame with an uncompressed IPv6 header to send.
+ *                  Will be translated to an 6LoWPAN IPHC frame.
+ * @param[in] ctx   Context for the packet. May be NULL.
+ * @param[in] page  Current 6Lo dispatch parsing page.
  *
- * @return  true, on success
- * @return  false, on error.
  */
-bool gnrc_sixlowpan_iphc_encode(gnrc_pktsnip_t *pkt);
+void gnrc_sixlowpan_iphc_send(gnrc_pktsnip_t *pkt, void *ctx, unsigned page);
 
 #ifdef __cplusplus
 }

sys/net/gnrc/network_layer/sixlowpan/gnrc_sixlowpan.c

@@ -101,6 +101,51 @@ void gnrc_sixlowpan_dispatch_send(gnrc_pktsnip_t *pkt, void *context,
     }
 }
 
+void gnrc_sixlowpan_multiplex_by_size(gnrc_pktsnip_t *pkt,
+                                      size_t orig_datagram_size,
+                                      gnrc_netif_t *netif,
+                                      unsigned page)
+{
+    assert(pkt != NULL);
+    assert(netif != NULL);
+    size_t datagram_size = gnrc_pkt_len(pkt->next);
+    DEBUG("6lo: iface->sixlo.max_frag_size = %u for interface %i\n",
+          netif->sixlo.max_frag_size, netif->pid);
+    if ((netif->sixlo.max_frag_size == 0) ||
+        (datagram_size <= netif->sixlo.max_frag_size)) {
+        DEBUG("6lo: Dispatch for sending\n");
+        gnrc_sixlowpan_dispatch_send(pkt, NULL, page);
+    }
+#ifdef MODULE_GNRC_SIXLOWPAN_FRAG
+    else if (orig_datagram_size <= SIXLOWPAN_FRAG_MAX_LEN) {
+        DEBUG("6lo: Send fragmented (%u > %u)\n",
+              (unsigned int)datagram_size, netif->sixlo.max_frag_size);
+        gnrc_sixlowpan_msg_frag_t *fragment_msg;
+
+        fragment_msg = gnrc_sixlowpan_msg_frag_get();
+        if (fragment_msg == NULL) {
+            DEBUG("6lo: Not enough resources to fragment packet. "
+                  "Dropping packet\n");
+            gnrc_pktbuf_release_error(pkt, ENOMEM);
+            return;
+        }
+        fragment_msg->pid = netif->pid;
+        fragment_msg->pkt = pkt;
+        fragment_msg->datagram_size = orig_datagram_size;
+        /* Sending the first fragment has an offset==0 */
+        fragment_msg->offset = 0;
+
+        gnrc_sixlowpan_frag_send(pkt, fragment_msg, page);
+    }
+#endif
+    else {
+        (void)orig_datagram_size;
+        DEBUG("6lo: packet too big (%u > %u)\n",
+              (unsigned int)datagram_size, netif->sixlo.max_frag_size);
+        gnrc_pktbuf_release_error(pkt, EMSGSIZE);
+    }
+}
+
 static void _receive(gnrc_pktsnip_t *pkt)
 {
     gnrc_pktsnip_t *payload;
@@ -225,8 +270,8 @@ static inline bool _add_uncompr_disp(gnrc_pktsnip_t *pkt)
 static void _send(gnrc_pktsnip_t *pkt)
 {
     gnrc_netif_hdr_t *hdr;
-    gnrc_pktsnip_t *pkt2;
+    gnrc_pktsnip_t *tmp;
-    gnrc_netif_t *iface;
+    gnrc_netif_t *netif;
     /* datagram_size: pure IPv6 packet without 6LoWPAN dispatches or compression */
     size_t datagram_size;
 
@@ -242,95 +287,37 @@ static void _send(gnrc_pktsnip_t *pkt)
         return;
     }
 
-    pkt2 = gnrc_pktbuf_start_write(pkt);
+    tmp = gnrc_pktbuf_start_write(pkt);
 
-    if (pkt2 == NULL) {
+    if (tmp == NULL) {
         DEBUG("6lo: no space left in packet buffer\n");
         gnrc_pktbuf_release(pkt);
         return;
     }
+    pkt = tmp;
+    hdr = pkt->data;
+    netif = gnrc_netif_get_by_pid(hdr->if_pid);
+    datagram_size = gnrc_pkt_len(pkt->next);
 
-    hdr = pkt2->data;
+    if (netif == NULL) {
-    iface = gnrc_netif_get_by_pid(hdr->if_pid);
-    datagram_size = gnrc_pkt_len(pkt2->next);
-
-    if (iface == NULL) {
         DEBUG("6lo: Can not get 6LoWPAN specific interface information.\n");
         gnrc_pktbuf_release(pkt);
         return;
     }
 
 #ifdef MODULE_GNRC_SIXLOWPAN_IPHC
-    if (iface->flags & GNRC_NETIF_FLAGS_6LO_HC) {
+    if (netif->flags & GNRC_NETIF_FLAGS_6LO_HC) {
-        if (!gnrc_sixlowpan_iphc_encode(pkt2)) {
+        gnrc_sixlowpan_iphc_send(pkt, NULL, 0);
-            DEBUG("6lo: error on IPHC encoding\n");
+        return;
-            gnrc_pktbuf_release(pkt2);
-            return;
-        }
-        /* IPHC dispatch does not count on dispatch length since it _shortens_
-         * the datagram */
     }
-    else {
+#endif
-        if (!_add_uncompr_disp(pkt2)) {
+    if (!_add_uncompr_disp(pkt)) {
-            /* adding uncompressed dispatch failed */
-            DEBUG("6lo: no space left in packet buffer\n");
-            gnrc_pktbuf_release(pkt2);
-            return;
-        }
-    }
-#else
-    /* suppress clang-analyzer report about iface being not read */
-    (void) iface;
-    if (!_add_uncompr_disp(pkt2)) {
         /* adding uncompressed dispatch failed */
         DEBUG("6lo: no space left in packet buffer\n");
-        gnrc_pktbuf_release(pkt2);
+        gnrc_pktbuf_release(pkt);
         return;
     }
-#endif
+    gnrc_sixlowpan_multiplex_by_size(pkt, datagram_size, netif, 0);
-    DEBUG("6lo: iface->sixlo.max_frag_size = %" PRIu8 " for interface %"
-          PRIkernel_pid "\n", iface->sixlo.max_frag_size, hdr->if_pid);
-
-    /* Note, that datagram_size cannot be used here, because the header size
-     * might be changed by IPHC. */
-    if ((iface->sixlo.max_frag_size == 0) ||
-        (gnrc_pkt_len(pkt2->next) <= iface->sixlo.max_frag_size)) {
-        DEBUG("6lo: Send SND command for %p to %" PRIu16 "\n",
-              (void *)pkt2, hdr->if_pid);
-        gnrc_sixlowpan_dispatch_send(pkt2, NULL, 0);
-        return;
-    }
-#ifdef MODULE_GNRC_SIXLOWPAN_FRAG
-    else if (datagram_size <= SIXLOWPAN_FRAG_MAX_LEN) {
-        DEBUG("6lo: Send fragmented (%u > %" PRIu8 ")\n",
-              (unsigned int)datagram_size, iface->sixlo.max_frag_size);
-        gnrc_sixlowpan_msg_frag_t *fragment_msg;
-
-        fragment_msg = gnrc_sixlowpan_msg_frag_get();
-        if (fragment_msg == NULL) {
-            DEBUG("6lo: Not enough resources to fragment packet. Dropping packet\n");
-            gnrc_pktbuf_release(pkt2);
-            return;
-        }
-        fragment_msg->pid = hdr->if_pid;
-        fragment_msg->pkt = pkt2;
-        fragment_msg->datagram_size = datagram_size;
-        /* Sending the first fragment has an offset==0 */
-        fragment_msg->offset = 0;
-
-        gnrc_sixlowpan_frag_send(pkt2, fragment_msg, 0);
-    }
-    else {
-        DEBUG("6lo: packet too big (%u > %" PRIu16 ")\n",
-              (unsigned int)datagram_size, (uint16_t)SIXLOWPAN_FRAG_MAX_LEN);
-        gnrc_pktbuf_release(pkt2);
-    }
-#else
-    (void) datagram_size;
-    DEBUG("6lo: packet too big (%u > %" PRIu8 ")\n",
-          (unsigned int)datagram_size, iface->sixlo.max_frag_size);
-    gnrc_pktbuf_release(pkt2);
-#endif
 }
 
 static void *_event_loop(void *args)

sys/net/gnrc/network_layer/sixlowpan/iphc/gnrc_sixlowpan_iphc.c

@@ -23,6 +23,7 @@
 #include "net/ipv6/hdr.h"
 #include "net/gnrc.h"
 #include "net/gnrc/sixlowpan/ctx.h"
+#include "net/gnrc/sixlowpan/internal.h"
 #include "net/sixlowpan.h"
 #include "utlist.h"
 #include "net/gnrc/nettype.h"
@@ -581,20 +582,25 @@ static inline size_t iphc_nhc_udp_encode(gnrc_pktsnip_t *udp, ipv6_hdr_t *ipv6_h
 }
 #endif
 
-bool gnrc_sixlowpan_iphc_encode(gnrc_pktsnip_t *pkt)
+void gnrc_sixlowpan_iphc_send(gnrc_pktsnip_t *pkt, void *ctx, unsigned page)
 {
+    assert(pkt != NULL);
     gnrc_netif_hdr_t *netif_hdr = pkt->data;
     ipv6_hdr_t *ipv6_hdr = pkt->next->data;
     uint8_t *iphc_hdr;
-    uint16_t inline_pos = SIXLOWPAN_IPHC_HDR_LEN;
-    bool addr_comp = false, nhc_comp = false;
     gnrc_sixlowpan_ctx_t *src_ctx = NULL, *dst_ctx = NULL;
     gnrc_pktsnip_t *dispatch = gnrc_pktbuf_add(NULL, NULL, pkt->next->size,
                                                GNRC_NETTYPE_SIXLOWPAN);
+    bool addr_comp = false, nhc_comp = false;
+    /* datagram size before compression */
+    size_t orig_datagram_size = gnrc_pkt_len(pkt->next);
+    uint16_t inline_pos = SIXLOWPAN_IPHC_HDR_LEN;
 
+    (void)ctx;
     if (dispatch == NULL) {
         DEBUG("6lo iphc: error allocating dispatch space\n");
-        return false;
+        gnrc_pktbuf_release(pkt);
+        return;
     }
 
     iphc_hdr = dispatch->data;
@@ -892,7 +898,9 @@ bool gnrc_sixlowpan_iphc_encode(gnrc_pktsnip_t *pkt)
     dispatch->next = pkt->next;
     pkt->next = dispatch;
 
-    return true;
+    gnrc_netif_t *netif = gnrc_netif_get_by_pid(netif_hdr->if_pid);
+    assert(netif != NULL);
+    gnrc_sixlowpan_multiplex_by_size(pkt, orig_datagram_size, netif, page);
 }
 
 /** @} */