Supported Operations on Private Data Types

Secure operations are supported via our gcEVM extension, which is implemented through a set of precompiled contracts.

To introduce a new private datum into the gcEVM, the function should include an argument of type Inputtext. Inside the function, you must call ValidateCiphertext, which validates the input and returns a Garbledtext if successful or an error otherwise. Note that values of type Garbledtext can be used in secure computations, and can also be converted into a Ciphertext type by calling Offboard. Values of type Ciphertext can be stored temporarily in memory or permanently as a state variable. Note that values of type Ciphertext cannot be used for secure computations, and therefore must be converted back into a Garbledtext type by calling Onboard in order to perform additional secure computations on them.

List of Operations and Their Required Gas

Each operation within the network requires a specific amount of gas. It's important to note that the following gas allocations are intended to be proportional and serve as initial estimates. The final determination of gas requirements will be made at a later stage, taking into account various factors such as network performance, usage patterns, and protocol optimizations.

List of arithmetic operations supported using Garbledtext and their required Gas units

Operation	Bool	gtUint8	gtUint16	gtUint32	gtUint64	gtString**
And	12005	12040	12080	12160	12320
Or	12005	12042	12084	12169	12339
Xor	12000	12000	12001	12003	12006
Shl		12620	14571	22467	54233
Shr		12969	15960	28009	76377
Add		12037	12080	12167	12340
CheckedAdd		26252	26318	26407	26577
Sub		12080	12165	12337	12679
CheckedSub		26341	26403	26576	26917
Mul		12620	14571	22467	54233
CheckedMul		26859	28754	36684	68536
Div		12969	15960	28009	76377
Rem		12969	15960	28009	76377
Min	12010	12121	12249	12503	13012
Max	12010	12121	12249	12503	13012
Lt	12005	12080	12166	12337	12679
Gt	12010	12121	12249	12503	13012
Ge	12005	12080	12165	12337	12679
Le	12010	12122	12249	12503	13012
Eq	12000	12037	12079	12164	12334	12334
Ne	12000	12037	12079	12164	12334	12334
Not	12000

** Note that the gas units listed for the gtString type are for every 8 characters in the string. This is due to the way encrypted strings are represented in memory/storage.

Other Special Function and Their Required Gas units

A more detailed explanation on the functionality of these functions can be found in the MPC Core library.

Operation	gtBool	gtUint8	gtUint16	gtUint32	gtUint64	gtString**
SetPublic	12000	12000	12001	12003	12006	12006
Decrypt	12000	12000	12001	12003	12006	12006
Onboard	47039	47039	47039	47039	47039	47039
ValidateCiphertext	47039	47039	47039	47039	47039	47039
Offboard	47039	47040	47040	47042	47045	47045
OffboardToUser	47039	47040	47040	47042	47045	47045
Rand	6000	6000	6000	6000	6000
RandBoundedBits	6000	6000	6000	6000	6000
Mux	12005	12041	12083	12166	12332
Transfer		12201	12413	12837	13685
TransferWithAllowance		12301	12619	13255	14527

** Note that the gas units listed for the gtString type are for every 8 characters in the string. This is due to the way encrypted strings are represented in memory/storage.