Squashed commit upgrading to mbedtls-2.16.5

Squash merging branch import/mbedtls-2.16.5

058aefb2bfa4 ("core: mbedtls: use SHA-256 crypto accelerated routines")
bcef9baed8f1 ("core: mbedtls: use SHA-1 crypto accelerated routines")
c9359f31db12 ("core: mbedtls: use AES crypto accelerated routines")
0e6c1e2642c7 ("core: merge tee_*_get_digest_size() into a single function")
0cb3c28a2f4d ("libmbedtls: mbedtls_mpi_exp_mod(): optimize mempool usage")
5abf0e6ab72e ("libmbedtls: mbedtls_mpi_exp_mod(): reduce stack usage")
2ccc08ac7fef ("libmbedtls: preserve mempool usage on reinit")
cd2a24648569 ("libmbedtls: mbedtls_mpi_exp_mod() initialize W")
7727182ecb56 ("libmbedtls: fix no CRT issue")
120737075dcf ("libmbedtls: add interfaces in mbedtls for context memory operation")
1126250b3af8 ("libmbedtls: add missing source file chachapoly.c")
23972e9f1c98 ("libmedtls: mpi_miller_rabin: increase count limit")
1fcbc05b3cd2 ("libmbedtls: add mbedtls_mpi_init_mempool()")
66e03f068078 ("libmbedtls: make mbedtls_mpi_mont*() available")
d07e0ce56236 ("libmbedtls: refine mbedtls license header")
491ee2cd0ff4 ("mbedtls: configure mbedtls to reach for config")
9b6cee685d9a ("mbedtls: remove default include/mbedtls/config.h")
84f7467a0a91 ("Import mbedtls-2.16.5")

Signed-off-by: Jerome Forissier <jerome@forissier.org>
Acked-by: Jens Wiklander <jens.wiklander@linaro.org>
diff --git a/lib/libmbedtls/mbedtls/library/havege.c b/lib/libmbedtls/mbedtls/library/havege.c
index 0d0c885..c5e6126 100644
--- a/lib/libmbedtls/mbedtls/library/havege.c
+++ b/lib/libmbedtls/mbedtls/library/havege.c
@@ -38,8 +38,19 @@
 #include "mbedtls/timing.h"
 #include "mbedtls/platform_util.h"
 
+#include <limits.h>
 #include <string.h>
 
+/* If int isn't capable of storing 2^32 distinct values, the code of this
+ * module may cause a processor trap or a miscalculation. If int is more
+ * than 32 bits, the code may not calculate the intended values. */
+#if INT_MIN + 1 != -0x7fffffff
+#error "The HAVEGE module requires int to be exactly 32 bits, with INT_MIN = -2^31."
+#endif
+#if UINT_MAX != 0xffffffff
+#error "The HAVEGE module requires unsigned to be exactly 32 bits."
+#endif
+
 /* ------------------------------------------------------------------------
  * On average, one iteration accesses two 8-word blocks in the havege WALK
  * table, and generates 16 words in the RES array.
@@ -54,7 +65,7 @@
  * ------------------------------------------------------------------------
  */
 
-#define SWAP(X,Y) { int *T = X; X = Y; Y = T; }
+#define SWAP(X,Y) { unsigned *T = (X); (X) = (Y); (Y) = T; }
 
 #define TST1_ENTER if( PTEST & 1 ) { PTEST ^= 3; PTEST >>= 1;
 #define TST2_ENTER if( PTEST & 1 ) { PTEST ^= 3; PTEST >>= 1;
@@ -77,7 +88,7 @@
     PTX = (PT1 >> 18) & 7;                              \
     PT1 &= 0x1FFF;                                      \
     PT2 &= 0x1FFF;                                      \
-    CLK = (int) mbedtls_timing_hardclock();                            \
+    CLK = (unsigned) mbedtls_timing_hardclock();        \
                                                         \
     i = 0;                                              \
     A = &WALK[PT1    ]; RES[i++] ^= *A;                 \
@@ -100,7 +111,7 @@
                                                         \
     IN = (*A >> (5)) ^ (*A << (27)) ^ CLK;              \
     *A = (*B >> (6)) ^ (*B << (26)) ^ CLK;              \
-    *B = IN; CLK = (int) mbedtls_timing_hardclock();                   \
+    *B = IN; CLK = (unsigned) mbedtls_timing_hardclock(); \
     *C = (*C >> (7)) ^ (*C << (25)) ^ CLK;              \
     *D = (*D >> (8)) ^ (*D << (24)) ^ CLK;              \
                                                         \
@@ -151,19 +162,20 @@
     PT1 ^= (PT2 ^ 0x10) & 0x10;                         \
                                                         \
     for( n++, i = 0; i < 16; i++ )                      \
-        hs->pool[n % MBEDTLS_HAVEGE_COLLECT_SIZE] ^= RES[i];
+        POOL[n % MBEDTLS_HAVEGE_COLLECT_SIZE] ^= RES[i];
 
 /*
  * Entropy gathering function
  */
 static void havege_fill( mbedtls_havege_state *hs )
 {
-    int i, n = 0;
-    int  U1,  U2, *A, *B, *C, *D;
-    int PT1, PT2, *WALK, RES[16];
-    int PTX, PTY, CLK, PTEST, IN;
+    unsigned i, n = 0;
+    unsigned  U1,  U2, *A, *B, *C, *D;
+    unsigned PT1, PT2, *WALK, *POOL, RES[16];
+    unsigned PTX, PTY, CLK, PTEST, IN;
 
-    WALK = hs->WALK;
+    WALK = (unsigned *) hs->WALK;
+    POOL = (unsigned *) hs->pool;
     PT1  = hs->PT1;
     PT2  = hs->PT2;