Reduce stack usage of test_suite_rsa

Reduce the stack usage of the `test_suite_rsa` by reducing the
size of the buffers used in the tests, to a reasonable big enough size,
and change the data size to decrypt in the data file.
diff --git a/tests/suites/test_suite_rsa.data b/tests/suites/test_suite_rsa.data
index 953b1ff..5e4de17 100644
--- a/tests/suites/test_suite_rsa.data
+++ b/tests/suites/test_suite_rsa.data
@@ -264,7 +264,7 @@
 
 RSA PKCS1 Decrypt #1 (Verify)
 depends_on:MBEDTLS_PKCS1_V15
-mbedtls_rsa_pkcs1_decrypt:"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":MBEDTLS_RSA_PKCS_V15:2048:16:"e79a373182bfaa722eb035f772ad2a9464bd842de59432c18bbab3a7dfeae318c9b915ee487861ab665a40bd6cda560152578e8579016c929df99fea05b4d64efca1d543850bc8164b40d71ed7f3fa4105df0fb9b9ad2a18ce182c8a4f4f975bea9aa0b9a1438a27a28e97ac8330ef37383414d1bd64607d6979ac050424fd17":16:"c6749cbb0db8c5a177672d4728a8b22392b2fc4d3b8361d5c0d5055a1b4e46d821f757c24eef2a51c561941b93b3ace7340074c058c9bb48e7e7414f42c41da4cccb5c2ba91deb30c586b7fb18af12a52995592ad139d3be429add6547e044becedaf31fa3b39421e24ee034fbf367d11f6b8f88ee483d163b431e1654ad3e89":16:"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":16:"3":1000:"4E636AF98E40F3ADCFCCB698F4E80B9F":0
+mbedtls_rsa_pkcs1_decrypt:"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":MBEDTLS_RSA_PKCS_V15:2048:16:"e79a373182bfaa722eb035f772ad2a9464bd842de59432c18bbab3a7dfeae318c9b915ee487861ab665a40bd6cda560152578e8579016c929df99fea05b4d64efca1d543850bc8164b40d71ed7f3fa4105df0fb9b9ad2a18ce182c8a4f4f975bea9aa0b9a1438a27a28e97ac8330ef37383414d1bd64607d6979ac050424fd17":16:"c6749cbb0db8c5a177672d4728a8b22392b2fc4d3b8361d5c0d5055a1b4e46d821f757c24eef2a51c561941b93b3ace7340074c058c9bb48e7e7414f42c41da4cccb5c2ba91deb30c586b7fb18af12a52995592ad139d3be429add6547e044becedaf31fa3b39421e24ee034fbf367d11f6b8f88ee483d163b431e1654ad3e89":16:"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":16:"3":32:"4E636AF98E40F3ADCFCCB698F4E80B9F":0
 
 RSA PKCS1 Encrypt #2 (Data too large)
 depends_on:MBEDTLS_PKCS1_V15
@@ -272,7 +272,7 @@
 
 RSA PKCS1 Decrypt #2 (Data too small)
 depends_on:MBEDTLS_PKCS1_V15
-mbedtls_rsa_pkcs1_decrypt:"deadbeafcafedeadbeeffedcba9876":MBEDTLS_RSA_PKCS_V15:2048:16:"e79a373182bfaa722eb035f772ad2a9464bd842de59432c18bbab3a7dfeae318c9b915ee487861ab665a40bd6cda560152578e8579016c929df99fea05b4d64efca1d543850bc8164b40d71ed7f3fa4105df0fb9b9ad2a18ce182c8a4f4f975bea9aa0b9a1438a27a28e97ac8330ef37383414d1bd64607d6979ac050424fd17":16:"c6749cbb0db8c5a177672d4728a8b22392b2fc4d3b8361d5c0d5055a1b4e46d821f757c24eef2a51c561941b93b3ace7340074c058c9bb48e7e7414f42c41da4cccb5c2ba91deb30c586b7fb18af12a52995592ad139d3be429add6547e044becedaf31fa3b39421e24ee034fbf367d11f6b8f88ee483d163b431e1654ad3e89":16:"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":16:"3":1000:"4E636AF98E40F3ADCFCCB698F4E80B9F":MBEDTLS_ERR_RSA_PRIVATE_FAILED + MBEDTLS_ERR_MPI_BAD_INPUT_DATA
+mbedtls_rsa_pkcs1_decrypt:"deadbeafcafedeadbeeffedcba9876":MBEDTLS_RSA_PKCS_V15:2048:16:"e79a373182bfaa722eb035f772ad2a9464bd842de59432c18bbab3a7dfeae318c9b915ee487861ab665a40bd6cda560152578e8579016c929df99fea05b4d64efca1d543850bc8164b40d71ed7f3fa4105df0fb9b9ad2a18ce182c8a4f4f975bea9aa0b9a1438a27a28e97ac8330ef37383414d1bd64607d6979ac050424fd17":16:"c6749cbb0db8c5a177672d4728a8b22392b2fc4d3b8361d5c0d5055a1b4e46d821f757c24eef2a51c561941b93b3ace7340074c058c9bb48e7e7414f42c41da4cccb5c2ba91deb30c586b7fb18af12a52995592ad139d3be429add6547e044becedaf31fa3b39421e24ee034fbf367d11f6b8f88ee483d163b431e1654ad3e89":16:"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":16:"3":32:"4E636AF98E40F3ADCFCCB698F4E80B9F":MBEDTLS_ERR_RSA_PRIVATE_FAILED + MBEDTLS_ERR_MPI_BAD_INPUT_DATA
 
 RSA PKCS1 Decrypt #4 (Output buffer too small)
 depends_on:MBEDTLS_PKCS1_V15
diff --git a/tests/suites/test_suite_rsa.function b/tests/suites/test_suite_rsa.function
index 89c84e8..d4acc2d 100644
--- a/tests/suites/test_suite_rsa.function
+++ b/tests/suites/test_suite_rsa.function
@@ -472,8 +472,8 @@
                              char * input_N, int radix_E, char * input_E,
                              data_t * result_hex_str, int result )
 {
-    unsigned char hash_result[1000];
-    unsigned char output[1000];
+    unsigned char hash_result[MBEDTLS_MD_MAX_SIZE];
+    unsigned char output[256];
     mbedtls_rsa_context ctx;
     mbedtls_mpi N, P, Q, E;
     rnd_pseudo_info rnd_info;
@@ -482,8 +482,8 @@
     mbedtls_mpi_init( &Q ); mbedtls_mpi_init( &E );
     mbedtls_rsa_init( &ctx, padding_mode, 0 );
 
-    memset( hash_result, 0x00, 1000 );
-    memset( output, 0x00, 1000 );
+    memset( hash_result, 0x00, sizeof( hash_result ) );
+    memset( output, 0x00, sizeof( output ) );
     memset( &rnd_info, 0, sizeof( rnd_pseudo_info ) );
 
     TEST_ASSERT( mbedtls_mpi_read_string( &P, radix_P, input_P ) == 0 );
@@ -522,14 +522,14 @@
                                char * input_N, int radix_E, char * input_E,
                                data_t * result_str, int result )
 {
-    unsigned char hash_result[1000];
+    unsigned char hash_result[MBEDTLS_MD_MAX_SIZE];
     mbedtls_rsa_context ctx;
 
     mbedtls_mpi N, E;
 
     mbedtls_mpi_init( &N ); mbedtls_mpi_init( &E );
     mbedtls_rsa_init( &ctx, padding_mode, 0 );
-    memset( hash_result, 0x00, 1000 );
+    memset( hash_result, 0x00, sizeof( hash_result ) );
 
     TEST_ASSERT( mbedtls_mpi_read_string( &N, radix_N, input_N ) == 0 );
     TEST_ASSERT( mbedtls_mpi_read_string( &E, radix_E, input_E ) == 0 );
@@ -557,7 +557,7 @@
                          int radix_N, char * input_N, int radix_E,
                          char * input_E, data_t * result_hex_str )
 {
-    unsigned char output[1000];
+    unsigned char output[256];
     mbedtls_rsa_context ctx;
     mbedtls_mpi N, P, Q, E;
     rnd_pseudo_info rnd_info;
@@ -566,7 +566,7 @@
     mbedtls_mpi_init( &N ); mbedtls_mpi_init( &P );
     mbedtls_mpi_init( &Q ); mbedtls_mpi_init( &E );
 
-    memset( output, 0x00, 1000 );
+    memset( output, 0x00, sizeof( output ) );
     memset( &rnd_info, 0, sizeof( rnd_pseudo_info ) );
 
     TEST_ASSERT( mbedtls_mpi_read_string( &P, radix_P, input_P ) == 0 );
@@ -593,7 +593,7 @@
     if( padding_mode == MBEDTLS_RSA_PKCS_V15 )
     {
         int res;
-        memset( output, 0x00, 1000 );
+        memset( output, 0x00, sizeof( output) );
 
         res = mbedtls_rsa_rsaes_pkcs1_v15_encrypt( &ctx,
                     &rnd_pseudo_rand, &rnd_info, MBEDTLS_RSA_PRIVATE,
@@ -627,7 +627,7 @@
                            char * input_N, int radix_E, char * input_E,
                            data_t * result_str, int correct )
 {
-    unsigned char output[1000];
+    unsigned char output[256];
     mbedtls_rsa_context ctx;
 
     mbedtls_mpi N, E;
@@ -688,7 +688,7 @@
                                 int radix_E, char * input_E,
                                 data_t * result_hex_str, int result )
 {
-    unsigned char output[1000];
+    unsigned char output[256];
     mbedtls_rsa_context ctx;
     rnd_pseudo_info rnd_info;
 
@@ -698,7 +698,7 @@
     memset( &rnd_info, 0, sizeof( rnd_pseudo_info ) );
 
     mbedtls_rsa_init( &ctx, padding_mode, 0 );
-    memset( output, 0x00, 1000 );
+    memset( output, 0x00, sizeof( output ) );
 
     TEST_ASSERT( mbedtls_mpi_read_string( &N, radix_N, input_N ) == 0 );
     TEST_ASSERT( mbedtls_mpi_read_string( &E, radix_E, input_E ) == 0 );
@@ -729,14 +729,14 @@
                                 int radix_E, char * input_E,
                                 data_t * result_hex_str, int result )
 {
-    unsigned char output[1000];
+    unsigned char output[256];
     mbedtls_rsa_context ctx;
 
     mbedtls_mpi N, E;
 
     mbedtls_mpi_init( &N ); mbedtls_mpi_init( &E );
     mbedtls_rsa_init( &ctx, padding_mode, 0 );
-    memset( output, 0x00, 1000 );
+    memset( output, 0x00, sizeof( output ) );
 
     TEST_ASSERT( mbedtls_mpi_read_string( &N, radix_N, input_N ) == 0 );
     TEST_ASSERT( mbedtls_mpi_read_string( &E, radix_E, input_E ) == 0 );
@@ -769,7 +769,7 @@
                                 int max_output, data_t * result_hex_str,
                                 int result )
 {
-    unsigned char output[1000];
+    unsigned char output[32];
     mbedtls_rsa_context ctx;
     size_t output_len;
     rnd_pseudo_info rnd_info;
@@ -780,7 +780,7 @@
 
     mbedtls_rsa_init( &ctx, padding_mode, 0 );
 
-    memset( output, 0x00, 1000 );
+    memset( output, 0x00, sizeof( output ) );
     memset( &rnd_info, 0, sizeof( rnd_pseudo_info ) );
 
 
@@ -815,7 +815,7 @@
                          char * input_N, int radix_E, char * input_E,
                          data_t * result_hex_str, int result )
 {
-    unsigned char output[1000];
+    unsigned char output[256];
     mbedtls_rsa_context ctx, ctx2; /* Also test mbedtls_rsa_copy() while at it */
 
     mbedtls_mpi N, E;
@@ -823,7 +823,7 @@
     mbedtls_mpi_init( &N ); mbedtls_mpi_init( &E );
     mbedtls_rsa_init( &ctx, MBEDTLS_RSA_PKCS_V15, 0 );
     mbedtls_rsa_init( &ctx2, MBEDTLS_RSA_PKCS_V15, 0 );
-    memset( output, 0x00, 1000 );
+    memset( output, 0x00, sizeof( output ) );
 
     TEST_ASSERT( mbedtls_mpi_read_string( &N, radix_N, input_N ) == 0 );
     TEST_ASSERT( mbedtls_mpi_read_string( &E, radix_E, input_E ) == 0 );
@@ -847,7 +847,7 @@
 
     TEST_ASSERT( mbedtls_rsa_check_pubkey( &ctx2 ) == 0 );
 
-    memset( output, 0x00, 1000 );
+    memset( output, 0x00, sizeof( output ) );
     TEST_ASSERT( mbedtls_rsa_public( &ctx2, message_str->x, output ) == result );
     if( result == 0 )
     {
@@ -869,7 +869,7 @@
                           char * input_E, data_t * result_hex_str,
                           int result )
 {
-    unsigned char output[1000];
+    unsigned char output[256];
     mbedtls_rsa_context ctx, ctx2; /* Also test mbedtls_rsa_copy() while at it */
     mbedtls_mpi N, P, Q, E;
     rnd_pseudo_info rnd_info;
@@ -896,7 +896,7 @@
     /* repeat three times to test updating of blinding values */
     for( i = 0; i < 3; i++ )
     {
-        memset( output, 0x00, 1000 );
+        memset( output, 0x00, sizeof( output ) );
         TEST_ASSERT( mbedtls_rsa_private( &ctx, rnd_pseudo_rand, &rnd_info,
                                   message_str->x, output ) == result );
         if( result == 0 )
@@ -913,7 +913,7 @@
 
     TEST_ASSERT( mbedtls_rsa_check_privkey( &ctx2 ) == 0 );
 
-    memset( output, 0x00, 1000 );
+    memset( output, 0x00, sizeof( output ) );
     TEST_ASSERT( mbedtls_rsa_private( &ctx2, rnd_pseudo_rand, &rnd_info,
                               message_str->x, output ) == result );
     if( result == 0 )
@@ -1577,11 +1577,11 @@
                              int successive )
 {
     /* Exported buffers */
-    unsigned char bufNe[1000];
-    unsigned char bufPe[1000];
-    unsigned char bufQe[1000];
-    unsigned char bufDe[1000];
-    unsigned char bufEe[1000];
+    unsigned char bufNe[256];
+    unsigned char bufPe[128];
+    unsigned char bufQe[128];
+    unsigned char bufDe[256];
+    unsigned char bufEe[1];
 
     mbedtls_rsa_context ctx;