commit 6adbb2a351a469336b52ef98485af714e0d35cb0
author Thomas Daubney <thomas.daubney@arm.com> Thu Jan 18 18:10:32 2024 +0000
committer Thomas Daubney <thomas.daubney@arm.com> Mon Feb 12 12:48:36 2024 +0000
tree 38af96402bba1efa56335656a1847cb94e709ba1
parent ad736991bb59211118a29fe115367c24495300c2

Implement safe buffer copying in asymm. encryption

Use local copy buffer macros to implement safe
copy mechanism in asymmetric encryption API.

Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>

library/psa_crypto.c

diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index 57844c5..c52a477 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -3283,11 +3283,11 @@
 
 psa_status_t psa_asymmetric_encrypt(mbedtls_svc_key_id_t key,
                                     psa_algorithm_t alg,
-                                    const uint8_t *input,
+                                    const uint8_t *input_external,
                                     size_t input_length,
-                                    const uint8_t *salt,
+                                    const uint8_t *salt_external,
                                     size_t salt_length,
-                                    uint8_t *output,
+                                    uint8_t *output_external,
                                     size_t output_size,
                                     size_t *output_length)
 {
@@ -3295,6 +3295,9 @@
     psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
     psa_key_slot_t *slot;
     psa_key_attributes_t attributes;
+    LOCAL_INPUT_DECLARE(input_external, input);
+    LOCAL_INPUT_DECLARE(salt_external, salt);
+    LOCAL_OUTPUT_DECLARE(output_external, output);
 
     (void) input;
     (void) input_length;
@@ -3323,6 +3326,9 @@
         .core = slot->attr
     };
 
+    LOCAL_INPUT_ALLOC(input_external, input_length, input);
+    LOCAL_INPUT_ALLOC(salt_external, salt_length, salt);
+    LOCAL_OUTPUT_ALLOC(output_external, output_size, output);
     status = psa_driver_wrapper_asymmetric_encrypt(
         &attributes, slot->key.data, slot->key.bytes,
         alg, input, input_length, salt, salt_length,
@@ -3330,16 +3336,20 @@
 exit:
     unlock_status = psa_unregister_read(slot);
 
+    LOCAL_INPUT_FREE(input_external, input);
+    LOCAL_INPUT_FREE(salt_external, salt);
+    LOCAL_OUTPUT_FREE(output_external, output);
+
     return (status == PSA_SUCCESS) ? unlock_status : status;
 }
 
 psa_status_t psa_asymmetric_decrypt(mbedtls_svc_key_id_t key,
                                     psa_algorithm_t alg,
-                                    const uint8_t *input,
+                                    const uint8_t *input_external,
                                     size_t input_length,
-                                    const uint8_t *salt,
+                                    const uint8_t *salt_external,
                                     size_t salt_length,
-                                    uint8_t *output,
+                                    uint8_t *output_external,
                                     size_t output_size,
                                     size_t *output_length)
 {
@@ -3348,6 +3358,10 @@
     psa_key_slot_t *slot;
     psa_key_attributes_t attributes;
 
+    LOCAL_INPUT_DECLARE(input_external, input);
+    LOCAL_INPUT_DECLARE(salt_external, salt);
+    LOCAL_OUTPUT_DECLARE(output_external, output);
+
     (void) input;
     (void) input_length;
     (void) salt;
@@ -3374,6 +3388,9 @@
         .core = slot->attr
     };
 
+    LOCAL_INPUT_ALLOC(input_external, input_length, input);
+    LOCAL_INPUT_ALLOC(salt_external, salt_length, salt);
+    LOCAL_OUTPUT_ALLOC(output_external, output_size, output);
     status = psa_driver_wrapper_asymmetric_decrypt(
         &attributes, slot->key.data, slot->key.bytes,
         alg, input, input_length, salt, salt_length,
@@ -3382,6 +3399,10 @@
 exit:
     unlock_status = psa_unregister_read(slot);
 
+    LOCAL_INPUT_FREE(input_external, input);
+    LOCAL_INPUT_FREE(salt_external, salt);
+    LOCAL_OUTPUT_FREE(output_external, output);
+
     return (status == PSA_SUCCESS) ? unlock_status : status;
 }