WIP field hashing support

src_features/signMessageEIP712/field_hash.c

@@ -3,34 +3,140 @@
 #include "field_hash.h"
 #include "encode_field.h"
 #include "path.h"
+#include "mem.h"
 #include "eip712.h"
+#include "shared_context.h"
 
-const uint8_t *field_hash(const void *const structs_array,
-                          const uint8_t *const data,
-                          const uint8_t data_length)
+static s_field_hashing *fh = NULL;
+
+static bool field_hash_init(void)
 {
+    if (fh == NULL)
+    {
+        if ((fh = mem_alloc(sizeof(*fh))) == NULL)
+        {
+            return false;
+        }
+        fh->state = FHS_IDLE;
+    }
+    return true;
+}
+
+const uint8_t *field_hash(const uint8_t *data,
+                          uint8_t data_length,
+                          bool partial)
+{
+    const void *field_ptr;
     const char *type;
     uint8_t typelen;
     const char *key;
     uint8_t keylen;
-    const void *field;
+    e_type field_type;
+    uint8_t *hash_ptr = NULL;
 
-    (void)structs_array;
     (void)data;
-    (void)data_length;
-    // get field by path
-    //encode_integer(data, data_length);
-    field = path_get_field();
-    if (field != NULL)
+    if ((fh == NULL) && (field_hash_init() == false))
     {
+        return NULL;
+    }
+    // get field by path
+    if ((field_ptr = path_get_field()) == NULL)
+    {
+        return NULL;
+    }
+    field_type = struct_field_type(field_ptr);
+    if (fh->state == FHS_IDLE) // first packet for this frame
+    {
+        fh->remaining_size = (data[0] << 8) | data[1]; // network byte order
+        data += sizeof(uint16_t);
+        data_length -= sizeof(uint16_t);
+        fh->state = FHS_WAITING_FOR_MORE;
+        cx_keccak_init((cx_hash_t*)&global_sha3, 256); // init hash
+    }
+    fh->remaining_size -= data_length;
+    // if a dynamic type -> continue progressive hash
+    if (IS_DYN(field_type))
+    {
+        cx_hash((cx_hash_t*)&global_sha3,
+                0,
+                data,
+                data_length,
+                NULL,
+                0);
+    }
+    if (fh->remaining_size == 0)
+    {
+        if (partial) // only makes sense if marked as complete
+        {
+            return NULL;
+        }
         printf("==> ");
-        type = get_struct_field_typename(field, &typelen);
+        type = get_struct_field_typename(field_ptr, &typelen);
         fwrite(type, sizeof(char), typelen, stdout);
         printf(" ");
-        key = get_struct_field_keyname(field, &keylen);
+        key = get_struct_field_keyname(field_ptr, &keylen);
         fwrite(key, sizeof(char), keylen, stdout);
         printf("\n");
+
+        uint8_t *value = NULL;
+
+        if (!IS_DYN(field_type))
+        {
+            switch (field_type)
+            {
+                case TYPE_SOL_INT:
+                case TYPE_SOL_UINT:
+                case TYPE_SOL_BYTES_FIX:
+                    value = encode_integer(data, data_length);
+                    break;
+                case TYPE_SOL_ADDRESS:
+                    value = encode_address(data, data_length);
+                    break;
+                case TYPE_SOL_BOOL:
+                    value = encode_boolean((bool*)data, data_length);
+                    break;
+                case TYPE_CUSTOM:
+                default:
+                    printf("Unknown solidity type!\n");
+                    return NULL;
+            }
+
+            if (value == NULL)
+            {
+                return NULL;
+            }
+            cx_hash((cx_hash_t*)&global_sha3,
+                    0,
+                    (uint8_t*)value,
+                    EIP_712_ENCODED_FIELD_LENGTH,
+                    NULL,
+                    0);
+
+            // restore the memory location
+            mem_dealloc(EIP_712_ENCODED_FIELD_LENGTH);
+        }
+
+        if ((hash_ptr = mem_alloc(KECCAK256_HASH_BYTESIZE)) == NULL)
+        {
+            return NULL;
+        }
+        // copy hash into memory
+        cx_hash((cx_hash_t*)&global_sha3,
+                CX_LAST,
+                NULL,
+                0,
+                hash_ptr,
+                KECCAK256_HASH_BYTESIZE);
+
         path_advance();
+        fh->state = FHS_IDLE;
     }
-    return NULL;
+    else
+    {
+        if (!partial || !IS_DYN(field_type)) // only makes sense if marked as partial
+        {
+            return NULL;
+        }
+    }
+    return hash_ptr;
 }