commit e193ea8cb9df86586d1b90f88a8c1c97851de1cd
author Paul Elliott <paul.elliott@arm.com> Fri Oct 01 13:00:16 2021 +0100
committer Paul Elliott <paul.elliott@arm.com> Thu Oct 07 18:06:03 2021 +0100
tree e3752ffb9f856789a04bfa7bb1e044f1d9832004
parent 0c7c524b250771487584c0f4f0e1a71f4d2c2277

Add Multipart AEAD CCM internal implementation

Signed-off-by: Paul Elliott <paul.elliott@arm.com>

library/psa_crypto_aead.c

diff --git a/library/psa_crypto_aead.c b/library/psa_crypto_aead.c
index a72865c..9dd40dd 100644
--- a/library/psa_crypto_aead.c
+++ b/library/psa_crypto_aead.c
@@ -346,13 +346,6 @@
 {
     psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
 
-#if defined(MBEDTLS_PSA_BUILTIN_ALG_CCM)
-    if( operation->alg == PSA_ALG_CCM )
-    {
-        return( PSA_ERROR_NOT_SUPPORTED );
-    }
-#endif /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
-
     status = psa_aead_setup( operation, attributes, key_buffer,
                              key_buffer_size, alg );
 
@@ -373,13 +366,6 @@
 {
     psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
 
-#if defined(MBEDTLS_PSA_BUILTIN_ALG_CCM)
-    if( operation->alg == PSA_ALG_CCM )
-    {
-        return( PSA_ERROR_NOT_SUPPORTED );
-    }
-#endif /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
-
     status = psa_aead_setup( operation, attributes, key_buffer,
                              key_buffer_size, alg );
 
@@ -409,6 +395,18 @@
     }
     else
 #endif /* MBEDTLS_PSA_BUILTIN_ALG_GCM */
+#if defined(MBEDTLS_PSA_BUILTIN_ALG_CCM)
+    if( operation->alg == PSA_ALG_CCM )
+    {
+        status = mbedtls_to_psa_error(
+                   mbedtls_ccm_starts( &operation->ctx.ccm,
+                                       operation->is_encrypt ?
+                                       MBEDTLS_CCM_ENCRYPT : MBEDTLS_CCM_DECRYPT,
+                                       nonce,
+                                       nonce_length ) );
+    }
+    else
+#endif /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
 #if defined(MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305)
     if( operation->alg == PSA_ALG_CHACHA20_POLY1305 )
     {
@@ -446,11 +444,22 @@
     size_t ad_length,
     size_t plaintext_length )
 {
-    /* Nothing here yet, work is currently done in PSA Core, however support
-     * for CCM will require this function. */
+
+#if defined(MBEDTLS_PSA_BUILTIN_ALG_CCM)
+    if( operation->alg == PSA_ALG_CCM )
+    {
+        return( mbedtls_to_psa_error(
+                         mbedtls_ccm_set_lengths( &operation->ctx.ccm,
+                                                 ad_length,
+                                                 plaintext_length,
+                                                 operation->tag_length ) ) );
+
+    }
+#else /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
     ( void ) operation;
     ( void ) ad_length;
     ( void ) plaintext_length;
+#endif /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
 
     return ( PSA_SUCCESS );
 }
@@ -471,6 +480,14 @@
     }
     else
 #endif /* MBEDTLS_PSA_BUILTIN_ALG_GCM */
+#if defined(MBEDTLS_PSA_BUILTIN_ALG_CCM)
+    if( operation->alg == PSA_ALG_CCM )
+    {
+        status = mbedtls_to_psa_error(
+            mbedtls_ccm_update_ad( &operation->ctx.ccm, input, input_length ) );
+    }
+    else
+#endif /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
 #if defined(MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305)
     if( operation->alg == PSA_ALG_CHACHA20_POLY1305 )
     {
@@ -521,6 +538,20 @@
     }
     else
 #endif /* MBEDTLS_PSA_BUILTIN_ALG_GCM */
+#if defined(MBEDTLS_PSA_BUILTIN_ALG_CCM)
+    if( operation->alg == PSA_ALG_CCM )
+    {
+        if( output_size < input_length )
+            return( PSA_ERROR_BUFFER_TOO_SMALL );
+
+        status = mbedtls_to_psa_error(
+           mbedtls_ccm_update( &operation->ctx.ccm,
+                               input, input_length,
+                               output, output_size,
+                               &update_output_length ) );
+    }
+    else
+#endif /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
 #if defined(MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305)
     if( operation->alg == PSA_ALG_CHACHA20_POLY1305 )
     {
@@ -577,6 +608,20 @@
     }
     else
 #endif /* MBEDTLS_PSA_BUILTIN_ALG_GCM */
+#if defined(MBEDTLS_PSA_BUILTIN_ALG_CCM)
+    if( operation->alg == PSA_ALG_CCM )
+    {
+        /* tag must be big enough to store a tag of size passed into set
+         * lengths. */
+        if( tag_size < operation->tag_length )
+            return( PSA_ERROR_BUFFER_TOO_SMALL );
+
+        status = mbedtls_to_psa_error(
+                           mbedtls_ccm_finish( &operation->ctx.ccm,
+                                               tag, operation->tag_length ) );
+    }
+    else
+#endif /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
 #if defined(MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305)
     if( operation->alg == PSA_ALG_CHACHA20_POLY1305 )
     {