diff --git a/ChangeLog b/ChangeLog
index c7d86ad8a..69d7e1948 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -13,6 +13,9 @@ API Changes
      Migration helpers scripts/rename.pl and include/mbedlts/compat-1.3.h are
      provided.
    * Headers are now found in the 'mbedtls' directory (previously 'polarssl').
+   * The following _init() functions that could return errors have
+     been split into an _init() that returns void and another function:
+     mbedtls_ccm_init() -> mbedtls_ccm_setkey()
    * In the threading layer, mbedtls_mutex_init() and mbedtls_mutex_free() now
      return void.
    * ecdsa_write_signature() gained an addtional md_alg argument and
diff --git a/include/mbedtls/ccm.h b/include/mbedtls/ccm.h
index 7ee3a379b..894794d82 100644
--- a/include/mbedtls/ccm.h
+++ b/include/mbedtls/ccm.h
@@ -41,6 +41,15 @@ typedef struct {
 }
 mbedtls_ccm_context;
 
+/**
+ * \brief           Initialize CCM context (just makes references valid)
+ *                  Makes the context ready for mbedtls_ccm_setkey() or
+ *                  mbedtls_ccm_free().
+ *
+ * \param ctx       CCM context to initialize
+ */
+void mbedtls_ccm_init( mbedtls_ccm_context *ctx );
+
 /**
  * \brief           CCM initialization (encryption and decryption)
  *
@@ -51,8 +60,10 @@ mbedtls_ccm_context;
  *
  * \return          0 if successful, or a cipher specific error code
  */
-int mbedtls_ccm_init( mbedtls_ccm_context *ctx, mbedtls_cipher_id_t cipher,
-              const unsigned char *key, unsigned int keysize );
+int mbedtls_ccm_setkey( mbedtls_ccm_context *ctx,
+                        mbedtls_cipher_id_t cipher,
+                        const unsigned char *key,
+                        unsigned int keysize );
 
 /**
  * \brief           Free a CCM context and underlying cipher sub-context
diff --git a/library/ccm.c b/library/ccm.c
index 72eed388d..957fda9ea 100644
--- a/library/ccm.c
+++ b/library/ccm.c
@@ -61,8 +61,15 @@ static void mbedtls_zeroize( void *v, size_t n ) {
 /*
  * Initialize context
  */
-int mbedtls_ccm_init( mbedtls_ccm_context *ctx, mbedtls_cipher_id_t cipher,
-              const unsigned char *key, unsigned int keysize )
+void mbedtls_ccm_init( mbedtls_ccm_context *ctx )
+{
+    memset( ctx, 0, sizeof( mbedtls_ccm_context ) );
+}
+
+int mbedtls_ccm_setkey( mbedtls_ccm_context *ctx,
+                        mbedtls_cipher_id_t cipher,
+                        const unsigned char *key,
+                        unsigned int keysize )
 {
     int ret;
     const mbedtls_cipher_info_t *cipher_info;
@@ -398,7 +405,9 @@ int mbedtls_ccm_self_test( int verbose )
     size_t i;
     int ret;
 
-    if( mbedtls_ccm_init( &ctx, MBEDTLS_CIPHER_ID_AES, key, 8 * sizeof key ) != 0 )
+    mbedtls_ccm_init( &ctx );
+
+    if( mbedtls_ccm_setkey( &ctx, MBEDTLS_CIPHER_ID_AES, key, 8 * sizeof key ) != 0 )
     {
         if( verbose != 0 )
             mbedtls_printf( "  CCM: setup failed" );
diff --git a/library/cipher_wrap.c b/library/cipher_wrap.c
index ebc3c4f47..eb291b683 100644
--- a/library/cipher_wrap.c
+++ b/library/cipher_wrap.c
@@ -395,7 +395,7 @@ static const mbedtls_cipher_info_t aes_256_gcm_info = {
 static int ccm_aes_setkey_wrap( void *ctx, const unsigned char *key,
                                 unsigned int key_length )
 {
-    return mbedtls_ccm_init( (mbedtls_ccm_context *) ctx, MBEDTLS_CIPHER_ID_AES,
+    return mbedtls_ccm_setkey( (mbedtls_ccm_context *) ctx, MBEDTLS_CIPHER_ID_AES,
                      key, key_length );
 }
 
@@ -752,7 +752,7 @@ static const mbedtls_cipher_info_t camellia_256_gcm_info = {
 static int ccm_camellia_setkey_wrap( void *ctx, const unsigned char *key,
                                      unsigned int key_length )
 {
-    return mbedtls_ccm_init( (mbedtls_ccm_context *) ctx, MBEDTLS_CIPHER_ID_CAMELLIA,
+    return mbedtls_ccm_setkey( (mbedtls_ccm_context *) ctx, MBEDTLS_CIPHER_ID_CAMELLIA,
                      key, key_length );
 }
 
diff --git a/programs/test/benchmark.c b/programs/test/benchmark.c
index 56e31e02a..afb4652ca 100644
--- a/programs/test/benchmark.c
+++ b/programs/test/benchmark.c
@@ -433,13 +433,15 @@ int main( int argc, char *argv[] )
     {
         int keysize;
         mbedtls_ccm_context ccm;
+
+        mbedtls_ccm_init( &ccm );
         for( keysize = 128; keysize <= 256; keysize += 64 )
         {
             mbedtls_snprintf( title, sizeof( title ), "AES-CCM-%d", keysize );
 
             memset( buf, 0, sizeof( buf ) );
             memset( tmp, 0, sizeof( tmp ) );
-            mbedtls_ccm_init( &ccm, MBEDTLS_CIPHER_ID_AES, tmp, keysize );
+            mbedtls_ccm_setkey( &ccm, MBEDTLS_CIPHER_ID_AES, tmp, keysize );
 
             TIME_AND_TSC( title,
                     mbedtls_ccm_encrypt_and_tag( &ccm, BUFSIZE, tmp,
diff --git a/tests/suites/test_suite_ccm.data b/tests/suites/test_suite_ccm.data
index 9ce19eeec..90ba42d83 100644
--- a/tests/suites/test_suite_ccm.data
+++ b/tests/suites/test_suite_ccm.data
@@ -3,19 +3,19 @@ mbedtls_ccm_self_test:
 
 CCM init #1 AES-128: OK
 depends_on:MBEDTLS_AES_C
-mbedtls_ccm_init:MBEDTLS_CIPHER_ID_AES:128:0
+mbedtls_ccm_setkey:MBEDTLS_CIPHER_ID_AES:128:0
 
 CCM init #2 CAMELLIA-256: OK
 depends_on:MBEDTLS_CAMELLIA_C
-mbedtls_ccm_init:MBEDTLS_CIPHER_ID_CAMELLIA:256:0
+mbedtls_ccm_setkey:MBEDTLS_CIPHER_ID_CAMELLIA:256:0
 
 CCM init #3 AES-224: bad key size
 depends_on:MBEDTLS_AES_C
-mbedtls_ccm_init:MBEDTLS_CIPHER_ID_AES:224:MBEDTLS_ERR_CCM_BAD_INPUT
+mbedtls_ccm_setkey:MBEDTLS_CIPHER_ID_AES:224:MBEDTLS_ERR_CCM_BAD_INPUT
 
 CCM init #4 BLOWFISH-128: bad block size
 depends_on:MBEDTLS_BLOWFISH_C
-mbedtls_ccm_init:MBEDTLS_CIPHER_ID_BLOWFISH:128:MBEDTLS_ERR_CCM_BAD_INPUT
+mbedtls_ccm_setkey:MBEDTLS_CIPHER_ID_BLOWFISH:128:MBEDTLS_ERR_CCM_BAD_INPUT
 
 CCM lengths #1 all OK
 ccm_lengths:5:10:5:8:0
diff --git a/tests/suites/test_suite_ccm.function b/tests/suites/test_suite_ccm.function
index 6769ed6c1..13371eb9e 100644
--- a/tests/suites/test_suite_ccm.function
+++ b/tests/suites/test_suite_ccm.function
@@ -15,16 +15,18 @@ void mbedtls_ccm_self_test( )
 /* END_CASE */
 
 /* BEGIN_CASE */
-void mbedtls_ccm_init( int cipher_id, int key_size, int result )
+void mbedtls_ccm_setkey( int cipher_id, int key_size, int result )
 {
     mbedtls_ccm_context ctx;
     unsigned char key[32];
     int ret;
 
+    mbedtls_ccm_init( &ctx );
+
     memset( key, 0x2A, sizeof( key ) );
     TEST_ASSERT( (unsigned) key_size <= 8 * sizeof( key ) );
 
-    ret = mbedtls_ccm_init( &ctx, cipher_id, key, key_size );
+    ret = mbedtls_ccm_setkey( &ctx, cipher_id, key, key_size );
     TEST_ASSERT( ret == result );
 
 exit:
@@ -44,6 +46,8 @@ void ccm_lengths( int msg_len, int iv_len, int add_len, int tag_len, int res )
     unsigned char tag[18];
     int decrypt_ret;
 
+    mbedtls_ccm_init( &ctx );
+
     memset( key, 0, sizeof( key ) );
     memset( msg, 0, sizeof( msg ) );
     memset( iv, 0, sizeof( iv ) );
@@ -51,7 +55,7 @@ void ccm_lengths( int msg_len, int iv_len, int add_len, int tag_len, int res )
     memset( out, 0, sizeof( out ) );
     memset( tag, 0, sizeof( tag ) );
 
-    TEST_ASSERT( mbedtls_ccm_init( &ctx, MBEDTLS_CIPHER_ID_AES,
+    TEST_ASSERT( mbedtls_ccm_setkey( &ctx, MBEDTLS_CIPHER_ID_AES,
                                  key, 8 * sizeof( key ) ) == 0 );
 
     TEST_ASSERT( mbedtls_ccm_encrypt_and_tag( &ctx, msg_len, iv, iv_len, add, add_len,
@@ -84,6 +88,8 @@ void mbedtls_ccm_encrypt_and_tag( int cipher_id,
     mbedtls_ccm_context ctx;
     size_t key_len, msg_len, iv_len, add_len, tag_len, result_len;
 
+    mbedtls_ccm_init( &ctx );
+
     memset( key, 0x00, sizeof( key ) );
     memset( msg, 0x00, sizeof( msg ) );
     memset( iv, 0x00, sizeof( iv ) );
@@ -97,7 +103,7 @@ void mbedtls_ccm_encrypt_and_tag( int cipher_id,
     result_len = unhexify( result, result_hex );
     tag_len = result_len - msg_len;
 
-    TEST_ASSERT( mbedtls_ccm_init( &ctx, cipher_id, key, key_len * 8 ) == 0 );
+    TEST_ASSERT( mbedtls_ccm_setkey( &ctx, cipher_id, key, key_len * 8 ) == 0 );
 
     /* Test with input == output */
     TEST_ASSERT( mbedtls_ccm_encrypt_and_tag( &ctx, msg_len, iv, iv_len, add, add_len,
@@ -129,6 +135,8 @@ void mbedtls_ccm_auth_decrypt( int cipher_id,
     size_t key_len, msg_len, iv_len, add_len, result_len;
     int ret;
 
+    mbedtls_ccm_init( &ctx );
+
     memset( key, 0x00, sizeof( key ) );
     memset( msg, 0x00, sizeof( msg ) );
     memset( iv, 0x00, sizeof( iv ) );
@@ -154,7 +162,7 @@ void mbedtls_ccm_auth_decrypt( int cipher_id,
         result_len = unhexify( result, result_hex );
     }
 
-    TEST_ASSERT( mbedtls_ccm_init( &ctx, cipher_id, key, key_len * 8 ) == 0 );
+    TEST_ASSERT( mbedtls_ccm_setkey( &ctx, cipher_id, key, key_len * 8 ) == 0 );
 
     /* Test with input == output */
     TEST_ASSERT( mbedtls_ccm_auth_decrypt( &ctx, msg_len, iv, iv_len, add, add_len,