From 33402296d3dc37b0b53ca012611ea8cb33bc2aac Mon Sep 17 00:00:00 2001
From: Martine Lenders <m.lenders@fu-berlin.de>
Date: Tue, 9 Mar 2021 10:54:47 +0100
Subject: [PATCH] gnrc_sixlowpan_frag_sfr_congure: add congure_reno support

---
 makefiles/pseudomodules.inc.mk                |  5 ++
 .../net/gnrc/sixlowpan/frag/sfr/congure.h     |  1 +
 sys/net/gnrc/Makefile.dep                     |  4 ++
 .../sixlowpan/frag/sfr/congure_reno.c         | 69 +++++++++++++++++++
 4 files changed, 79 insertions(+)
 create mode 100644 sys/net/gnrc/network_layer/sixlowpan/frag/sfr/congure_reno.c

diff --git a/makefiles/pseudomodules.inc.mk b/makefiles/pseudomodules.inc.mk
index 1aa702b266..40ad9fa7bf 100644
--- a/makefiles/pseudomodules.inc.mk
+++ b/makefiles/pseudomodules.inc.mk
@@ -236,6 +236,11 @@ PSEUDOMODULES += gnrc_sixlowpan_frag_sfr_stats
 ## @{
 ##
 PSEUDOMODULES += gnrc_sixlowpan_frag_sfr_congure
+## @defgroup net_gnrc_sixlowpan_frag_sfr_congure_reno gnrc_sixlowpan_frag_sfr_congure_reno: TCP Reno
+## @brief  Congestion control for SFR using the [TCP Reno congestion control algorithm](@ref sys_congure_reno)
+## @{
+PSEUDOMODULES += gnrc_sixlowpan_frag_sfr_congure_reno
+## @}
 ## @defgroup net_gnrc_sixlowpan_frag_sfr_congure_quic gnrc_sixlowpan_frag_sfr_congure_quic: QUIC CC
 ## @brief  Congestion control for SFR using the [congestion control algorithm of QUIC](@ref sys_congure_quic)
 ## @{
diff --git a/sys/include/net/gnrc/sixlowpan/frag/sfr/congure.h b/sys/include/net/gnrc/sixlowpan/frag/sfr/congure.h
index b960e95b04..38ebbe2484 100644
--- a/sys/include/net/gnrc/sixlowpan/frag/sfr/congure.h
+++ b/sys/include/net/gnrc/sixlowpan/frag/sfr/congure.h
@@ -17,6 +17,7 @@
  *
  * - @ref net_gnrc_sixlowpan_frag_sfr_congure_sfr (the default)
  * - @ref net_gnrc_sixlowpan_frag_sfr_congure_quic
+ * - @ref net_gnrc_sixlowpan_frag_sfr_congure_reno
  * @{
  *
  * @file
diff --git a/sys/net/gnrc/Makefile.dep b/sys/net/gnrc/Makefile.dep
index b578d2d4b2..dd8e8dc588 100644
--- a/sys/net/gnrc/Makefile.dep
+++ b/sys/net/gnrc/Makefile.dep
@@ -248,6 +248,10 @@ ifneq (,$(filter gnrc_sixlowpan_frag_sfr_congure_quic,$(USEMODULE)))
   USEMODULE += congure_quic
 endif
 
+ifneq (,$(filter gnrc_sixlowpan_frag_sfr_congure_reno,$(USEMODULE)))
+  USEMODULE += congure_reno
+endif
+
 ifneq (,$(filter gnrc_sixlowpan_frag_sfr_congure,$(USEMODULE)))
   USEMODULE += gnrc_sixlowpan_frag_sfr
   ifeq (,$(filter gnrc_sixlowpan_frag_sfr_congure_% congure_mock,$(USEMODULE)))
diff --git a/sys/net/gnrc/network_layer/sixlowpan/frag/sfr/congure_reno.c b/sys/net/gnrc/network_layer/sixlowpan/frag/sfr/congure_reno.c
new file mode 100644
index 0000000000..6eca41496e
--- /dev/null
+++ b/sys/net/gnrc/network_layer/sixlowpan/frag/sfr/congure_reno.c
@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2021 Freie Universität Berlin
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @{
+ *
+ * @file
+ * @author  Martine Lenders <m.lenders@fu-berlin.de>
+ */
+
+#include "kernel_defines.h"
+#include "congure/reno.h"
+#include "net/gnrc/sixlowpan/config.h"
+
+#include "net/gnrc/sixlowpan/frag/sfr/congure.h"
+
+typedef congure_reno_snd_t _sfr_congure_snd_t;
+
+#define SFR_CONGURE_RENO_CONSTS { \
+        .fr = _fr, \
+        .same_wnd_adv = _same_wnd_adv, \
+        .init_mss = 1, \
+        .cwnd_lower = CONFIG_GNRC_SIXLOWPAN_SFR_MIN_WIN_SIZE, \
+        .cwnd_upper = CONFIG_GNRC_SIXLOWPAN_SFR_MAX_WIN_SIZE, \
+        /* TODO make those configurable via Kconfig? */ \
+        .init_ssthresh = 32U, \
+        .frthresh = 1U, \
+    }
+
+static void _fr(congure_reno_snd_t *c);
+static bool _same_wnd_adv(congure_reno_snd_t *c, congure_snd_ack_t *ack);
+
+static _sfr_congure_snd_t _sfr_congures[CONFIG_GNRC_SIXLOWPAN_FRAG_FB_SIZE];
+static const congure_reno_snd_consts_t _sfr_congure_reno_consts = SFR_CONGURE_RENO_CONSTS;
+
+congure_snd_t *gnrc_sixlowpan_frag_sfr_congure_snd_get(void)
+{
+    for (unsigned i = 0; i < ARRAY_SIZE(_sfr_congures); i++) {
+        if (_sfr_congures[i].super.driver == NULL) {
+            congure_reno_snd_setup(&_sfr_congures[i],
+                                   &_sfr_congure_reno_consts);
+            return &_sfr_congures[i].super;
+        }
+    }
+    return NULL;
+}
+
+static void _fr(congure_reno_snd_t *c)
+{
+    (void)c;
+    /* SFR resends when fast retransmits needs to be done anyways so
+     * do nothing */
+    return;
+}
+
+static bool _same_wnd_adv(congure_reno_snd_t *c, congure_snd_ack_t *ack)
+{
+    (void)c;
+    (void)ack;
+    /* Window size is not advertised with SFR, so always true */
+    return true;
+}
+
+/** @} */