From f79bc033609a66c3a49f69c769f28d21d79368c4 Mon Sep 17 00:00:00 2001
From: Sylvain Rochet <gradator@gradator.net>
Date: Sat, 18 Apr 2015 13:41:38 +0200
Subject: [PATCH] PPP, MPPE, optimized struct ppp_mppe_state size

---
 src/include/netif/ppp/mppe.h | 29 +++++++++++++++--------------
 src/netif/ppp/mppe.c         | 12 ++++++------
 2 files changed, 21 insertions(+), 20 deletions(-)

diff --git a/src/include/netif/ppp/mppe.h b/src/include/netif/ppp/mppe.h
index 4fa0274f..1556cd78 100644
--- a/src/include/netif/ppp/mppe.h
+++ b/src/include/netif/ppp/mppe.h
@@ -137,23 +137,24 @@
  */
 struct ppp_mppe_state {
 	arc4_context arc4;
-	unsigned char master_key[MPPE_MAX_KEY_LEN];
-	unsigned char session_key[MPPE_MAX_KEY_LEN];
-	unsigned keylen;	/* key length in bytes             */
-	/* NB: 128-bit == 16, 40-bit == 8! */
-	/* If we want to support 56-bit,   */
-	/* the unit has to change to bits  */
-	unsigned char bits;	/* MPPE control bits */
-	unsigned ccount;	/* 12-bit coherency count (seqno)  */
-	unsigned stateful;	/* stateful mode flag */
-	int discard;		/* stateful mode packet loss flag */
-	int sanity_errors;	/* take down LCP if too many */
-	int unit;
-	int debug;
+	u8_t master_key[MPPE_MAX_KEY_LEN];
+	u8_t session_key[MPPE_MAX_KEY_LEN];
+	u8_t keylen;                /* key length in bytes */
+	/* NB: 128-bit == 16, 40-bit == 8!
+	 * If we want to support 56-bit, the unit has to change to bits
+	 */
+	u8_t bits;                  /* MPPE control bits */
+	u16_t ccount;               /* 12-bit coherency count (seqno)  */
+	unsigned int stateful  :1;  /* stateful mode flag */
+	unsigned int discard   :1;  /* stateful mode packet loss flag */
+	unsigned int debug     :1;  /* debug flag */
+	unsigned int           :5;  /* 5 bit of padding to round out to 8 bits */
+	u16_t sanity_errors;        /* take down LCP if too many */
+	u8_t unit;
 };
 
 int mppe_init(struct ppp_mppe_state *state, unsigned char *options, int optlen,
-	int unit, int debug, const char *debugstr);
+	u8_t unit, u8_t debug, const char *debugstr);
 void mppe_comp_reset(struct ppp_mppe_state *state);
 err_t mppe_compress(struct ppp_mppe_state *state, struct pbuf **pb, u16_t protocol);
 void mppe_decomp_reset(struct ppp_mppe_state *state);
diff --git a/src/netif/ppp/mppe.c b/src/netif/ppp/mppe.c
index be8d3df7..fe197b46 100644
--- a/src/netif/ppp/mppe.c
+++ b/src/netif/ppp/mppe.c
@@ -117,7 +117,7 @@ static void mppe_rekey(struct ppp_mppe_state * state, int initial_key)
  * Initialize (de)compressor state.
  */
 int
-mppe_init(struct ppp_mppe_state *state, unsigned char *options, int optlen, int unit, int debug,
+mppe_init(struct ppp_mppe_state *state, unsigned char *options, int optlen, u8_t unit, u8_t debug,
 	  const char *debugstr)
 {
 	unsigned char mppe_opts;
@@ -218,7 +218,7 @@ mppe_compress(struct ppp_mppe_state *state, struct pbuf **pb, u16_t protocol)
 	pl = (u8_t*)np->payload;
 
 	state->ccount = (state->ccount + 1) % MPPE_CCOUNT_SPACE;
-	if (state->debug >= 7)
+	if (state->debug)
 		PPPDEBUG(LOG_DEBUG, ("mppe_compress[%d]: ccount %d\n", state->unit,
 		       state->ccount));
 	/* FIXME: use PUT* macros */
@@ -274,9 +274,9 @@ mppe_decompress(struct ppp_mppe_state *state, struct pbuf **pb)
 {
 	struct pbuf *n0 = *pb, *n;
 	u8_t *pl;
-	unsigned ccount;
-	int flushed;
-	int sanity = 0;
+	u16_t ccount;
+	u8_t flushed;
+	u8_t sanity = 0;
 
 	/* MPPE Header */
 	if (n0->len < MPPE_OVHD) {
@@ -290,7 +290,7 @@ mppe_decompress(struct ppp_mppe_state *state, struct pbuf **pb)
 	pl = (u8_t*)n0->payload;
 	flushed = MPPE_BITS(pl) & MPPE_BIT_FLUSHED;
 	ccount = MPPE_CCOUNT(pl);
-	if (state->debug >= 7)
+	if (state->debug)
 		PPPDEBUG(LOG_DEBUG, ("mppe_decompress[%d]: ccount %d\n",
 		       state->unit, ccount));