1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
use crate::ScriptError;
use ckb_error::Error;
use ckb_types::{
    core::{Cycle, ScriptHashType},
    packed::Script,
};
use ckb_vm::{
    machine::{VERSION0, VERSION1},
    memory::{FLAG_EXECUTABLE, FLAG_FREEZED},
    snapshot::{make_snapshot, Snapshot},
    CoreMachine as _, Memory, SupportMachine, ISA_B, ISA_IMC, ISA_MOP, RISCV_PAGESIZE,
};
use serde::{Deserialize, Serialize};
use std::convert::TryFrom;
use std::fmt;

#[cfg(has_asm)]
use ckb_vm::machine::asm::{AsmCoreMachine, AsmMachine};

#[cfg(not(has_asm))]
use ckb_vm::{DefaultCoreMachine, SparseMemory, TraceMachine, WXorXMemory};

/// The type of CKB-VM ISA.
pub type VmIsa = u8;
/// /// The type of CKB-VM version.
pub type VmVersion = u32;

#[cfg(has_asm)]
pub(crate) type CoreMachineType = AsmCoreMachine;
#[cfg(not(has_asm))]
pub(crate) type CoreMachineType = DefaultCoreMachine<u64, WXorXMemory<SparseMemory<u64>>>;

/// The type of core VM machine when uses ASM.
#[cfg(has_asm)]
pub type CoreMachine = Box<AsmCoreMachine>;
/// The type of core VM machine when doesn't use ASM.
#[cfg(not(has_asm))]
pub type CoreMachine = DefaultCoreMachine<u64, WXorXMemory<SparseMemory<u64>>>;

/// The version of CKB Script Verifier.
#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
pub enum ScriptVersion {
    /// CKB VM 0 with Syscall version 1.
    V0 = 0,
    /// CKB VM 1 with Syscall version 1 and version 2.
    V1 = 1,
}

impl ScriptVersion {
    /// Returns the latest version.
    pub const fn latest() -> Self {
        Self::V1
    }

    /// Returns the ISA set of CKB VM in current script version.
    pub fn vm_isa(self) -> VmIsa {
        match self {
            Self::V0 => ISA_IMC,
            Self::V1 => ISA_IMC | ISA_B | ISA_MOP,
        }
    }

    /// Returns the version of CKB VM in current script version.
    pub fn vm_version(self) -> VmVersion {
        match self {
            Self::V0 => VERSION0,
            Self::V1 => VERSION1,
        }
    }

    /// Returns the specific data script hash type.
    ///
    /// Returns:
    /// - `ScriptHashType::Data` for version 0;
    /// - `ScriptHashType::Data1` for version 1;
    pub fn data_hash_type(self) -> ScriptHashType {
        match self {
            Self::V0 => ScriptHashType::Data,
            Self::V1 => ScriptHashType::Data1,
        }
    }

    /// Creates a CKB VM core machine without cycles limit.
    ///
    /// In fact, there is still a limit of `max_cycles` which is set to `2^64-1`.
    pub fn init_core_machine_without_limit(self) -> CoreMachine {
        self.init_core_machine(u64::MAX)
    }

    /// Creates a CKB VM core machine.
    pub fn init_core_machine(self, max_cycles: Cycle) -> CoreMachine {
        let isa = self.vm_isa();
        let version = self.vm_version();
        CoreMachineType::new(isa, version, max_cycles)
    }
}

#[cfg(has_asm)]
pub(crate) type Machine<'a> = AsmMachine<'a>;
#[cfg(not(has_asm))]
pub(crate) type Machine<'a> = TraceMachine<'a, CoreMachine>;

pub struct ResumableMachine<'a> {
    pub(crate) machine: Machine<'a>,
    pub(crate) program_loaded: bool,
}

impl<'a> ResumableMachine<'a> {
    pub(crate) fn new(machine: Machine<'a>, program_loaded: bool) -> Self {
        ResumableMachine {
            machine,
            program_loaded,
        }
    }

    pub(crate) fn cycles(&self) -> Cycle {
        self.machine.machine.cycles()
    }

    #[cfg(test)]
    pub(crate) fn set_cycles(&mut self, cycles: Cycle) {
        self.machine.machine.set_cycles(cycles)
    }

    pub(crate) fn set_max_cycles(&mut self, cycles: Cycle) {
        set_vm_max_cycles(&mut self.machine, cycles)
    }

    pub fn program_loaded(&self) -> bool {
        self.program_loaded
    }
}

#[cfg(has_asm)]
pub(crate) fn set_vm_max_cycles(vm: &mut Machine<'_>, cycles: Cycle) {
    vm.set_max_cycles(cycles)
}

#[cfg(not(has_asm))]
pub(crate) fn set_vm_max_cycles(vm: &mut Machine<'_>, cycles: Cycle) {
    vm.machine.inner_mut().set_max_cycles(cycles)
}

/// A script group is defined as scripts that share the same hash.
///
/// A script group will only be executed once per transaction, the
/// script itself should check against all inputs/outputs in its group
/// if needed.
pub struct ScriptGroup {
    /// The script.
    ///
    /// A script group is a group of input and output cells that share the same script.
    pub script: Script,
    /// The script group type.
    pub group_type: ScriptGroupType,
    /// Indices of input cells.
    pub input_indices: Vec<usize>,
    /// Indices of output cells.
    pub output_indices: Vec<usize>,
}

impl ScriptGroup {
    /// Creates a new script group struct.
    pub fn new(script: &Script, group_type: ScriptGroupType) -> Self {
        Self {
            group_type,
            script: script.to_owned(),
            input_indices: vec![],
            output_indices: vec![],
        }
    }

    /// Creates a lock script group.
    pub fn from_lock_script(script: &Script) -> Self {
        Self::new(script, ScriptGroupType::Lock)
    }

    /// Creates a type script group.
    pub fn from_type_script(script: &Script) -> Self {
        Self::new(script, ScriptGroupType::Type)
    }
}

/// The script group type.
///
/// A cell can have a lock script and an optional type script. Even they reference the same script,
/// lock script and type script will not be grouped together.
#[derive(Copy, Clone, Serialize, Deserialize, PartialEq, Eq, Hash, Debug)]
#[serde(rename_all = "snake_case")]
pub enum ScriptGroupType {
    /// Lock script group.
    Lock,
    /// Type script group.
    Type,
}

impl fmt::Display for ScriptGroupType {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        match self {
            ScriptGroupType::Lock => write!(f, "Lock"),
            ScriptGroupType::Type => write!(f, "Type"),
        }
    }
}

/// Struct specifies which script has verified so far.
/// Snapshot is lifetime free, but capture snapshot need heavy memory copy
pub struct TransactionSnapshot {
    /// current suspended script index
    pub current: usize,
    /// vm snapshot
    pub snap: Option<(Snapshot, Cycle)>,
    /// current consumed cycle
    pub current_cycles: Cycle,
    /// limit cycles when snapshot create
    pub limit_cycles: Cycle,
}

/// Struct specifies which script has verified so far.
/// State lifetime bound with vm machine.
pub struct TransactionState<'a> {
    /// current suspended script index
    pub current: usize,
    /// vm state
    pub vm: Option<ResumableMachine<'a>>,
    /// current consumed cycle
    pub current_cycles: Cycle,
    /// limit cycles
    pub limit_cycles: Cycle,
    /// enable snapshot page dirty flags
    pub enable_backup_page_flags: bool,
    /// tracing data as code page index
    pub flags_tracing: Vec<(u64, u64)>,
}

impl TransactionState<'_> {
    /// Return next limit cycles according to max_cycles and step_cycles
    pub fn next_limit_cycles(&self, step_cycles: Cycle, max_cycles: Cycle) -> (Cycle, bool) {
        let remain = max_cycles - self.current_cycles;
        let next_limit = self.limit_cycles + step_cycles;

        if next_limit < remain {
            (next_limit, false)
        } else {
            (remain, true)
        }
    }
}

impl TransactionSnapshot {
    /// Return next limit cycles according to max_cycles and step_cycles
    pub fn next_limit_cycles(&self, step_cycles: Cycle, max_cycles: Cycle) -> (Cycle, bool) {
        let remain = max_cycles - self.current_cycles;
        let next_limit = self.limit_cycles + step_cycles;

        if next_limit < remain {
            (next_limit, false)
        } else {
            (remain, true)
        }
    }
}

impl TryFrom<TransactionState<'_>> for TransactionSnapshot {
    type Error = Error;

    fn try_from(state: TransactionState<'_>) -> Result<Self, Self::Error> {
        let TransactionState {
            current,
            vm,
            current_cycles,
            limit_cycles,
            enable_backup_page_flags,
            flags_tracing,
        } = state;

        let (snap, current_cycles) = if let Some(mut vm) = vm {
            // we should not capture snapshot if load program failed by exceeded cycles
            if vm.program_loaded {
                let vm_cycles = vm.cycles();
                // To be consistent with the mainnet, add this flag to enable this behavior after hardfork
                if !enable_backup_page_flags {
                    for (addr, memory_size) in flags_tracing {
                        let mut current_addr = addr;
                        while current_addr < addr + memory_size {
                            let page = current_addr / RISCV_PAGESIZE as u64;
                            vm.machine
                                .machine
                                .memory_mut()
                                .clear_flag(page, FLAG_EXECUTABLE | FLAG_FREEZED)
                                .map_err(|e| {
                                    ScriptError::VMInternalError(format!("{:?}", e))
                                        .unknown_source()
                                })?;
                            current_addr += RISCV_PAGESIZE as u64;
                        }
                    }
                }
                (
                    Some((
                        make_snapshot(&mut vm.machine.machine).map_err(|e| {
                            ScriptError::VMInternalError(format!("{:?}", e)).unknown_source()
                        })?,
                        vm_cycles,
                    )),
                    current_cycles,
                )
            } else {
                (None, current_cycles)
            }
        } else {
            (None, current_cycles)
        };

        Ok(TransactionSnapshot {
            current,
            snap,
            current_cycles,
            limit_cycles,
        })
    }
}

/// Enum represent resumable verify result
#[allow(clippy::large_enum_variant)]
#[derive(Debug)]
pub enum VerifyResult<'a> {
    /// Completed total cycles
    Completed(Cycle),
    /// Suspended state
    Suspended(TransactionState<'a>),
}

impl std::fmt::Debug for TransactionSnapshot {
    fn fmt(&self, f: &mut ::core::fmt::Formatter) -> std::fmt::Result {
        f.debug_struct("TransactionSnapshot")
            .field("current", &self.current)
            .field("current_cycles", &self.current_cycles)
            .field("limit_cycles", &self.limit_cycles)
            .finish()
    }
}

impl std::fmt::Debug for TransactionState<'_> {
    fn fmt(&self, f: &mut ::core::fmt::Formatter) -> std::fmt::Result {
        f.debug_struct("TransactionState")
            .field("current", &self.current)
            .field("current_cycles", &self.current_cycles)
            .field("limit_cycles", &self.limit_cycles)
            .finish()
    }
}