Struct evmil::CfaState

source · 
pub struct CfaState { /* private fields */ }

Implementations§

Examples found in repository?
src/cfa.rs (line 43)
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    pub fn push(self, val: AbstractValue) -> Self {
        CfaState::new(self.stack.push(val))
    }
    pub fn pop(mut self, n: usize) -> Self {
        assert!(n > 0);
        let mut stack = self.stack;
        for i in 0..n {
            stack = stack.pop();
        }
        CfaState::new(stack)
    }
    pub fn set(self, n:usize, val: AbstractValue) -> Self {
        CfaState::new(self.stack.set(n,val))
    }
}

impl Clone for CfaState {
    fn clone(&self) -> Self {
        CfaState::new(self.stack.clone())
    }
}

impl fmt::Display for CfaState {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        write!(f,"{}",self.stack)
    }
}

impl AbstractState for CfaState {
    fn is_reachable(&self) -> bool { !self.stack.is_bottom() }

    fn branch(&self, _pc: usize, insn: &Instruction) -> Self {
        match insn {
            JUMPI => self.clone().pop(2),
            JUMP => self.clone().pop(1),
            _ => {
                unreachable!()
            }
        }
    }

    fn peek(&self, n: usize) -> AbstractValue {
        self.stack.peek(n)
    }

    fn merge(&mut self, other: Self) -> bool {
        if *self != other {
            if !other.is_bottom() {
                if self.is_bottom() {
                    *self = other;
                    return true;
                } else {
                    return self.stack.merge_into(&other.stack);
                }
            }
        }
        false
    }

    fn bottom() -> Self { CfaState::new(BOTTOM_STACK) }

    fn origin() -> Self {
        CfaState::new(EMPTY_STACK)
    }
Examples found in repository?
src/cfa.rs (line 89)
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    fn merge(&mut self, other: Self) -> bool {
        if *self != other {
            if !other.is_bottom() {
                if self.is_bottom() {
                    *self = other;
                    return true;
                } else {
                    return self.stack.merge_into(&other.stack);
                }
            }
        }
        false
    }
Examples found in repository?
src/cfa.rs (line 117)
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    fn transfer(self, insn: &Instruction) -> CfaState {
        match insn {
            STOP => CfaState::bottom(),
            // 0s: Stop and Arithmetic Operations
            ADD|MUL|SUB|DIV|SDIV|MOD|SMOD|EXP|SIGNEXTEND => {
                self.pop(2).push(UNKNOWN)
            }
            ADDMOD|MULMOD => {
                self.pop(3).push(UNKNOWN)
            }
            // 0s: Stop and Arithmetic Operations
            ISZERO|NOT => {
                self.pop(1).push(UNKNOWN)
            }
            // Binary Comparators
            LT|GT|SLT|SGT|EQ => {
                self.pop(2).push(UNKNOWN)
            }
            // Binary bitwise operators
            AND|OR|XOR|BYTE|SHL|SHR|SAR => {
                self.pop(2).push(UNKNOWN)
            }
            // 20s: Keccak256
            KECCAK256 => {
                // NOTE: there is some kind of compiler bug which is
                // preventing me from putting this case in the
                // expected position.
                self.pop(2).push(UNKNOWN)
            }
            // 30s: Environmental Information
            ADDRESS => self.push(UNKNOWN),
            BALANCE => self.pop(1).push(UNKNOWN),
            ORIGIN => self.push(UNKNOWN),
            CALLER => self.push(UNKNOWN),
            CALLVALUE => self.push(UNKNOWN),
            CALLDATALOAD => self.pop(1).push(UNKNOWN),
            CALLDATASIZE => self.push(UNKNOWN),
            CALLDATACOPY => self.pop(3),
            CODESIZE => self.push(UNKNOWN),
            CODECOPY => self.pop(3),
            GASPRICE => self.push(UNKNOWN),
            EXTCODESIZE => self.pop(1).push(UNKNOWN),
            EXTCODECOPY => self.pop(4),
            RETURNDATASIZE => self.push(UNKNOWN),
            RETURNDATACOPY => self.pop(3),
            EXTCODEHASH => self.pop(1).push(UNKNOWN),
            // 40s: Block Information
            BLOCKHASH => self.pop(1).push(UNKNOWN),
            COINBASE => self.push(UNKNOWN),
            TIMESTAMP => self.push(UNKNOWN),
            NUMBER   => self.push(UNKNOWN),
            DIFFICULTY => self.push(UNKNOWN),
            GASLIMIT => self.push(UNKNOWN),
            CHAINID => self.push(UNKNOWN),
            SELFBALANCE => self.push(UNKNOWN),
            // 50s: Stack, Memory, Storage and Flow Operations
            POP => self.pop(1),
            MLOAD => self.pop(1).push(UNKNOWN),
            MSTORE|MSTORE8 => self.pop(2),
            SLOAD => self.pop(1).push(UNKNOWN),
            SSTORE => self.pop(2),
            JUMPI => self.pop(2),
            PC|MSIZE|GAS => self.push(UNKNOWN),
            JUMPDEST(_) => self, // nop
            // 60 & 70s: Push Operations
            PUSH(bytes) => {
                let n = util::from_be_bytes(&bytes);
                if n <= MAX_CODE_SIZE {
                    self.push(AbstractValue::Known(n as usize))
                } else {
                    self.push(UNKNOWN)
                }
            }
            // 80s: Duplicate Operations
            DUP(n) => {
                let m = (*n - 1) as usize;
                let nth = self.peek(m);
                self.push(nth)
            }
            // 90s: Exchange Operations
            SWAP(n) => {
                let m = (*n - 1) as usize;
                let x = self.peek(m);
                let y = self.peek(0);
                self.set(0,x).set(m,y)
            }
            // a0s: Logging Operations
            LOG(n) => {
                self.pop((n+2) as usize)
            }
            // f0s: System Operations
            CREATE => self.pop(3).push(UNKNOWN),
            CALL|CALLCODE => self.pop(7).push(UNKNOWN),
            DELEGATECALL|STATICCALL => self.pop(6).push(UNKNOWN),
            CREATE2 => self.pop(4).push(UNKNOWN),
            INVALID|JUMP|RETURN|REVERT => {
                CfaState::bottom()
            }
            SELFDESTRUCT => self.pop(1),
            _ => {
                // This is a catch all to ensure no instructions are
                // missed above.
                panic!("unknown instruction ({:?})",insn);
            }
        }
    }
Examples found in repository?
src/cfa.rs (line 75)
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    fn branch(&self, _pc: usize, insn: &Instruction) -> Self {
        match insn {
            JUMPI => self.clone().pop(2),
            JUMP => self.clone().pop(1),
            _ => {
                unreachable!()
            }
        }
    }

    fn peek(&self, n: usize) -> AbstractValue {
        self.stack.peek(n)
    }

    fn merge(&mut self, other: Self) -> bool {
        if *self != other {
            if !other.is_bottom() {
                if self.is_bottom() {
                    *self = other;
                    return true;
                } else {
                    return self.stack.merge_into(&other.stack);
                }
            }
        }
        false
    }

    fn bottom() -> Self { CfaState::new(BOTTOM_STACK) }

    fn origin() -> Self {
        CfaState::new(EMPTY_STACK)
    }

    // ============================================================================
    // Abstract Instruction Semantics (stack)
    // ============================================================================

    /// Update an abstract state with the effects of a given instruction.
    fn transfer(self, insn: &Instruction) -> CfaState {
        match insn {
            STOP => CfaState::bottom(),
            // 0s: Stop and Arithmetic Operations
            ADD|MUL|SUB|DIV|SDIV|MOD|SMOD|EXP|SIGNEXTEND => {
                self.pop(2).push(UNKNOWN)
            }
            ADDMOD|MULMOD => {
                self.pop(3).push(UNKNOWN)
            }
            // 0s: Stop and Arithmetic Operations
            ISZERO|NOT => {
                self.pop(1).push(UNKNOWN)
            }
            // Binary Comparators
            LT|GT|SLT|SGT|EQ => {
                self.pop(2).push(UNKNOWN)
            }
            // Binary bitwise operators
            AND|OR|XOR|BYTE|SHL|SHR|SAR => {
                self.pop(2).push(UNKNOWN)
            }
            // 20s: Keccak256
            KECCAK256 => {
                // NOTE: there is some kind of compiler bug which is
                // preventing me from putting this case in the
                // expected position.
                self.pop(2).push(UNKNOWN)
            }
            // 30s: Environmental Information
            ADDRESS => self.push(UNKNOWN),
            BALANCE => self.pop(1).push(UNKNOWN),
            ORIGIN => self.push(UNKNOWN),
            CALLER => self.push(UNKNOWN),
            CALLVALUE => self.push(UNKNOWN),
            CALLDATALOAD => self.pop(1).push(UNKNOWN),
            CALLDATASIZE => self.push(UNKNOWN),
            CALLDATACOPY => self.pop(3),
            CODESIZE => self.push(UNKNOWN),
            CODECOPY => self.pop(3),
            GASPRICE => self.push(UNKNOWN),
            EXTCODESIZE => self.pop(1).push(UNKNOWN),
            EXTCODECOPY => self.pop(4),
            RETURNDATASIZE => self.push(UNKNOWN),
            RETURNDATACOPY => self.pop(3),
            EXTCODEHASH => self.pop(1).push(UNKNOWN),
            // 40s: Block Information
            BLOCKHASH => self.pop(1).push(UNKNOWN),
            COINBASE => self.push(UNKNOWN),
            TIMESTAMP => self.push(UNKNOWN),
            NUMBER   => self.push(UNKNOWN),
            DIFFICULTY => self.push(UNKNOWN),
            GASLIMIT => self.push(UNKNOWN),
            CHAINID => self.push(UNKNOWN),
            SELFBALANCE => self.push(UNKNOWN),
            // 50s: Stack, Memory, Storage and Flow Operations
            POP => self.pop(1),
            MLOAD => self.pop(1).push(UNKNOWN),
            MSTORE|MSTORE8 => self.pop(2),
            SLOAD => self.pop(1).push(UNKNOWN),
            SSTORE => self.pop(2),
            JUMPI => self.pop(2),
            PC|MSIZE|GAS => self.push(UNKNOWN),
            JUMPDEST(_) => self, // nop
            // 60 & 70s: Push Operations
            PUSH(bytes) => {
                let n = util::from_be_bytes(&bytes);
                if n <= MAX_CODE_SIZE {
                    self.push(AbstractValue::Known(n as usize))
                } else {
                    self.push(UNKNOWN)
                }
            }
            // 80s: Duplicate Operations
            DUP(n) => {
                let m = (*n - 1) as usize;
                let nth = self.peek(m);
                self.push(nth)
            }
            // 90s: Exchange Operations
            SWAP(n) => {
                let m = (*n - 1) as usize;
                let x = self.peek(m);
                let y = self.peek(0);
                self.set(0,x).set(m,y)
            }
            // a0s: Logging Operations
            LOG(n) => {
                self.pop((n+2) as usize)
            }
            // f0s: System Operations
            CREATE => self.pop(3).push(UNKNOWN),
            CALL|CALLCODE => self.pop(7).push(UNKNOWN),
            DELEGATECALL|STATICCALL => self.pop(6).push(UNKNOWN),
            CREATE2 => self.pop(4).push(UNKNOWN),
            INVALID|JUMP|RETURN|REVERT => {
                CfaState::bottom()
            }
            SELFDESTRUCT => self.pop(1),
            _ => {
                // This is a catch all to ensure no instructions are
                // missed above.
                panic!("unknown instruction ({:?})",insn);
            }
        }
    }
Examples found in repository?
src/cfa.rs (line 196)
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    fn transfer(self, insn: &Instruction) -> CfaState {
        match insn {
            STOP => CfaState::bottom(),
            // 0s: Stop and Arithmetic Operations
            ADD|MUL|SUB|DIV|SDIV|MOD|SMOD|EXP|SIGNEXTEND => {
                self.pop(2).push(UNKNOWN)
            }
            ADDMOD|MULMOD => {
                self.pop(3).push(UNKNOWN)
            }
            // 0s: Stop and Arithmetic Operations
            ISZERO|NOT => {
                self.pop(1).push(UNKNOWN)
            }
            // Binary Comparators
            LT|GT|SLT|SGT|EQ => {
                self.pop(2).push(UNKNOWN)
            }
            // Binary bitwise operators
            AND|OR|XOR|BYTE|SHL|SHR|SAR => {
                self.pop(2).push(UNKNOWN)
            }
            // 20s: Keccak256
            KECCAK256 => {
                // NOTE: there is some kind of compiler bug which is
                // preventing me from putting this case in the
                // expected position.
                self.pop(2).push(UNKNOWN)
            }
            // 30s: Environmental Information
            ADDRESS => self.push(UNKNOWN),
            BALANCE => self.pop(1).push(UNKNOWN),
            ORIGIN => self.push(UNKNOWN),
            CALLER => self.push(UNKNOWN),
            CALLVALUE => self.push(UNKNOWN),
            CALLDATALOAD => self.pop(1).push(UNKNOWN),
            CALLDATASIZE => self.push(UNKNOWN),
            CALLDATACOPY => self.pop(3),
            CODESIZE => self.push(UNKNOWN),
            CODECOPY => self.pop(3),
            GASPRICE => self.push(UNKNOWN),
            EXTCODESIZE => self.pop(1).push(UNKNOWN),
            EXTCODECOPY => self.pop(4),
            RETURNDATASIZE => self.push(UNKNOWN),
            RETURNDATACOPY => self.pop(3),
            EXTCODEHASH => self.pop(1).push(UNKNOWN),
            // 40s: Block Information
            BLOCKHASH => self.pop(1).push(UNKNOWN),
            COINBASE => self.push(UNKNOWN),
            TIMESTAMP => self.push(UNKNOWN),
            NUMBER   => self.push(UNKNOWN),
            DIFFICULTY => self.push(UNKNOWN),
            GASLIMIT => self.push(UNKNOWN),
            CHAINID => self.push(UNKNOWN),
            SELFBALANCE => self.push(UNKNOWN),
            // 50s: Stack, Memory, Storage and Flow Operations
            POP => self.pop(1),
            MLOAD => self.pop(1).push(UNKNOWN),
            MSTORE|MSTORE8 => self.pop(2),
            SLOAD => self.pop(1).push(UNKNOWN),
            SSTORE => self.pop(2),
            JUMPI => self.pop(2),
            PC|MSIZE|GAS => self.push(UNKNOWN),
            JUMPDEST(_) => self, // nop
            // 60 & 70s: Push Operations
            PUSH(bytes) => {
                let n = util::from_be_bytes(&bytes);
                if n <= MAX_CODE_SIZE {
                    self.push(AbstractValue::Known(n as usize))
                } else {
                    self.push(UNKNOWN)
                }
            }
            // 80s: Duplicate Operations
            DUP(n) => {
                let m = (*n - 1) as usize;
                let nth = self.peek(m);
                self.push(nth)
            }
            // 90s: Exchange Operations
            SWAP(n) => {
                let m = (*n - 1) as usize;
                let x = self.peek(m);
                let y = self.peek(0);
                self.set(0,x).set(m,y)
            }
            // a0s: Logging Operations
            LOG(n) => {
                self.pop((n+2) as usize)
            }
            // f0s: System Operations
            CREATE => self.pop(3).push(UNKNOWN),
            CALL|CALLCODE => self.pop(7).push(UNKNOWN),
            DELEGATECALL|STATICCALL => self.pop(6).push(UNKNOWN),
            CREATE2 => self.pop(4).push(UNKNOWN),
            INVALID|JUMP|RETURN|REVERT => {
                CfaState::bottom()
            }
            SELFDESTRUCT => self.pop(1),
            _ => {
                // This is a catch all to ensure no instructions are
                // missed above.
                panic!("unknown instruction ({:?})",insn);
            }
        }
    }

Trait Implementations§

Update an abstract state with the effects of a given instruction.

Determines whether a given block is considered reachable or not.
Apply a given branch to this stage, yielding an updated state at the point of the branch.
Determine value on top of stack
Merge this state with another, whilst returning a flag indicating whether anything changed.
Identify bottom value
Identify origin value
Returns a copy of the value. Read more
Performs copy-assignment from source. Read more
Formats the value using the given formatter. Read more
Formats the value using the given formatter. Read more
This method tests for self and other values to be equal, and is used by ==.
This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

Auto Trait Implementations§

Blanket Implementations§

Gets the TypeId of self. Read more
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

The resulting type after obtaining ownership.
Creates owned data from borrowed data, usually by cloning. Read more
Uses borrowed data to replace owned data, usually by cloning. Read more
Converts the given value to a String. Read more
The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.