diff --git a/tests/suites/test_suite_asn1write.data b/tests/suites/test_suite_asn1write.data
index 9982d03..f98df4e 100644
--- a/tests/suites/test_suite_asn1write.data
+++ b/tests/suites/test_suite_asn1write.data
@@ -1,3 +1,87 @@
+ASN.1 Write BOOLEAN FALSE
+mbedtls_asn1_write_bool:0:"010100"
+
+ASN.1 Write BOOLEAN TRUE
+mbedtls_asn1_write_bool:1:"0101ff"
+
+ASN.1 Write int 0
+mbedtls_asn1_write_int:0:"020100"
+
+ASN.1 Write int 1
+mbedtls_asn1_write_int:1:"020101"
+
+ASN.1 Write int 127
+mbedtls_asn1_write_int:0x7f:"02017f"
+
+ASN.1 Write int 128
+mbedtls_asn1_write_int:0x80:"02020080"
+
+ASN.1 Write int 255
+mbedtls_asn1_write_int:0xff:"020200ff"
+
+ASN.1 Write int 256
+mbedtls_asn1_write_int:0x100:"02020100"
+
+ASN.1 Write int 32767
+mbedtls_asn1_write_int:0x7fff:"02027fff"
+
+ASN.1 Write int 32768
+mbedtls_asn1_write_int:0x8000:"0203008000"
+
+ASN.1 Write int 65535
+mbedtls_asn1_write_int:0xffff:"020300ffff"
+
+ASN.1 Write int 65536
+mbedtls_asn1_write_int:0x10000:"0203010000"
+
+ASN.1 Write int 8388607
+mbedtls_asn1_write_int:0x7fffff:"02037fffff"
+
+ASN.1 Write int 8388608
+mbedtls_asn1_write_int:0x800000:"020400800000"
+
+ASN.1 Write int 0x12345678
+mbedtls_asn1_write_int:0x12345678:"020412345678"
+
+ASN.1 Write int 2147483647
+mbedtls_asn1_write_int:0x7fffffff:"02047fffffff"
+
+#ASN.1 Write mpi 0
+#mbedtls_asn1_write_mpi:"00":"020100"
+
+ASN.1 Write mpi 1
+mbedtls_asn1_write_mpi:"01":"020101"
+
+ASN.1 Write mpi 0x7f
+mbedtls_asn1_write_mpi:"7f":"02017f"
+
+#ASN.1 Write mpi 0x80
+#mbedtls_asn1_write_mpi:"7f":"02020080"
+
+#ASN.1 Write mpi 0xff
+#mbedtls_asn1_write_mpi:"7f":"020200ff"
+
+ASN.1 Write mpi 0x100
+mbedtls_asn1_write_mpi:"0100":"02020100"
+
+ASN.1 Write mpi, 127*8-1 bits
+mbedtls_asn1_write_mpi:"7f7b16e05c1537de7c41cef1a0985d6a3ced98aec28e091874cbad6b5e40a5c956258f18861c28bed8ba808259339ee34b2e509c4080149474d5d5b86093f90c475a6443fc87e1a293d4151be625d652f1c32a00a018bba10c8a2ae5b2b0ee4be64e053dce9d07ec7919526c9dfcf2ec9fc3db485caa8e5a68a2cd0a427de8":"027f7f7b16e05c1537de7c41cef1a0985d6a3ced98aec28e091874cbad6b5e40a5c956258f18861c28bed8ba808259339ee34b2e509c4080149474d5d5b86093f90c475a6443fc87e1a293d4151be625d652f1c32a00a018bba10c8a2ae5b2b0ee4be64e053dce9d07ec7919526c9dfcf2ec9fc3db485caa8e5a68a2cd0a427de8"
+
+#ASN.1 Write mpi, 127*8 bits
+#mbedtls_asn1_write_mpi:"e77b16e05c1537de7c41cef1a0985d6a3ced98aec28e091874cbad6b5e40a5c956258f18861c28bed8ba808259339ee34b2e509c4080149474d5d5b86093f90c475a6443fc87e1a293d4151be625d652f1c32a00a018bba10c8a2ae5b2b0ee4be64e053dce9d07ec7919526c9dfcf2ec9fc3db485caa8e5a68a2cd0a427de8":"028180e77b16e05c1537de7c41cef1a0985d6a3ced98aec28e091874cbad6b5e40a5c956258f18861c28bed8ba808259339ee34b2e509c4080149474d5d5b86093f90c475a6443fc87e1a293d4151be625d652f1c32a00a018bba10c8a2ae5b2b0ee4be64e053dce9d07ec7919526c9dfcf2ec9fc3db485caa8e5a68a2cd0a427de8"
+
+ASN.1 Write mpi, 127*8+1 bits
+mbedtls_asn1_write_mpi:"108446d68934cc1af23c4cd909884d4bd737a1890e12f5ef8bf3d807d72feffa63c0bf2633345f8b8418d144617c871a7a0277ac0150eed4b3db7f9dff21114cd0d7f282400f03c931cb00c367550e374a1ed3762a1801ca714cfc8d5aac69707ca81e0661400ed0014d97cba48f94d835dd681fc3053c51958afbf7583cf49c":"028180108446d68934cc1af23c4cd909884d4bd737a1890e12f5ef8bf3d807d72feffa63c0bf2633345f8b8418d144617c871a7a0277ac0150eed4b3db7f9dff21114cd0d7f282400f03c931cb00c367550e374a1ed3762a1801ca714cfc8d5aac69707ca81e0661400ed0014d97cba48f94d835dd681fc3053c51958afbf7583cf49c"
+
+ASN.1 Write mpi, 255*8-1 bits
+mbedtls_asn1_write_mpi:"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":"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"
+
+#ASN.1 Write mpi, 255*8 bits
+#mbedtls_asn1_write_mpi:"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":"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"
+
+ASN.1 Write mpi, 256*8-1 bits
+mbedtls_asn1_write_mpi:"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":"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"
+
 ASN.1 Write Octet String #0 (Empty string)
 mbedtls_asn1_write_octet_string:"":"0400":2:2
 
diff --git a/tests/suites/test_suite_asn1write.function b/tests/suites/test_suite_asn1write.function
index e45583c..7dfc162 100644
--- a/tests/suites/test_suite_asn1write.function
+++ b/tests/suites/test_suite_asn1write.function
@@ -3,6 +3,53 @@
 
 #define GUARD_LEN 4
 #define GUARD_VAL 0x2a
+
+typedef struct
+{
+    unsigned char *output;
+    unsigned char *start;
+    unsigned char *end;
+    unsigned char *p;
+    size_t size;
+} generic_write_data_t;
+
+int generic_write_start_step( generic_write_data_t *data )
+{
+    test_set_step( data->size );
+    ASSERT_ALLOC( data->output, data->size == 0 ? 1 : data->size );
+    data->end = data->output + data->size;
+    data->p = data->end;
+    data->start = data->end - data->size;
+    return( 1 );
+exit:
+    return( 0 );
+}
+
+int generic_write_finish_step( generic_write_data_t *data,
+                               const data_t *expected, int ret )
+{
+    int ok = 0;
+
+    if( data->size < expected->len )
+    {
+        TEST_EQUAL( ret, MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
+    }
+    else
+    {
+        TEST_EQUAL( ret, data->end - data->p );
+        TEST_ASSERT( data->p >= data->start );
+        TEST_ASSERT( data->p <= data->end );
+        ASSERT_COMPARE( data->p, (size_t)( data->end - data->p ),
+                        expected->x, expected->len );
+    }
+    ok = 1;
+
+exit:
+    mbedtls_free( data->output );
+    data->output = NULL;
+    return( ok );
+}
+
 /* END_HEADER */
 
 /* BEGIN_DEPENDENCIES
@@ -11,6 +58,71 @@
  */
 
 /* BEGIN_CASE */
+void mbedtls_asn1_write_bool( int val, data_t *expected )
+{
+    generic_write_data_t data = { NULL, NULL, NULL, NULL, 0 };
+    int ret;
+
+    for( data.size = 0; data.size < expected->len + 1; data.size++ )
+    {
+        if( ! generic_write_start_step( &data ) )
+            goto exit;
+        ret = mbedtls_asn1_write_bool( &data.p, data.start, val );
+        if( ! generic_write_finish_step( &data, expected, ret ) )
+            goto exit;
+    }
+
+exit:
+    mbedtls_free( data.output );
+}
+/* END_CASE */
+
+/* BEGIN_CASE */
+void mbedtls_asn1_write_int( int val, data_t *expected )
+{
+    generic_write_data_t data = { NULL, NULL, NULL, NULL, 0 };
+    int ret;
+
+    for( data.size = 0; data.size < expected->len + 1; data.size++ )
+    {
+        if( ! generic_write_start_step( &data ) )
+            goto exit;
+        ret = mbedtls_asn1_write_int( &data.p, data.start, val );
+        if( ! generic_write_finish_step( &data, expected, ret ) )
+            goto exit;
+    }
+
+exit:
+    mbedtls_free( data.output );
+}
+/* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_BIGNUM_C */
+void mbedtls_asn1_write_mpi( data_t *val, data_t *expected )
+{
+    generic_write_data_t data = { NULL, NULL, NULL, NULL, 0 };
+    mbedtls_mpi mpi;
+    int ret;
+
+    mbedtls_mpi_init( &mpi );
+    TEST_ASSERT( mbedtls_mpi_read_binary( &mpi, val->x, val->len ) == 0 );
+
+    for( data.size = 0; data.size < expected->len + 1; data.size++ )
+    {
+        if( ! generic_write_start_step( &data ) )
+            goto exit;
+        ret = mbedtls_asn1_write_mpi( &data.p, data.start, &mpi );
+        if( ! generic_write_finish_step( &data, expected, ret ) )
+            goto exit;
+    }
+
+exit:
+    mbedtls_mpi_free( &mpi );
+    mbedtls_free( data.output );
+}
+/* END_CASE */
+
+/* BEGIN_CASE */
 void mbedtls_asn1_write_octet_string( data_t * str, data_t * asn1,
                                       int buf_len, int result )
 {