aboutsummaryrefslogtreecommitdiffstats
path: root/vm.go
blob: 353f4f39ef594b3f9c5414e4180dd339c306e16c (plain) (blame)
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
package main

import (
  "math"
  "math/big"
  "fmt"
  "strconv"
  _ "encoding/hex"
)

// Op codes
const (
  oSTOP       int = 0x00
  oADD        int = 0x10
  oSUB        int = 0x11
  oMUL        int = 0x12
  oDIV        int = 0x13
  oSDIV       int = 0x14
  oMOD        int = 0x15
  oSMOD       int = 0x16
  oEXP        int = 0x17
  oNEG        int = 0x18
  oLT         int = 0x20
  oLE         int = 0x21
  oGT         int = 0x22
  oGE         int = 0x23
  oEQ         int = 0x24
  oNOT        int = 0x25
  oSHA256     int = 0x30
  oRIPEMD160  int = 0x31
  oECMUL      int = 0x32
  oECADD      int = 0x33
  oSIGN       int = 0x34
  oRECOVER    int = 0x35
  oCOPY       int = 0x40
  oST         int = 0x41
  oLD         int = 0x42
  oSET        int = 0x43
  oJMP        int = 0x50
  oJMPI       int = 0x51
  oIND        int = 0x52
  oEXTRO      int = 0x60
  oBALANCE    int = 0x61
  oMKTX       int = 0x70
  oDATA       int = 0x80
  oDATAN      int = 0x81
  oMYADDRESS  int = 0x90
  oSUICIDE    int = 0xff
)

type OpType int
const (
  tNorm = iota
  tData
  tExtro
  tCrypto
)
type TxCallback func(opType OpType) bool

type Vm struct {
  // Memory stack
  stack map[string]string
  // Index ptr
  iptr int
  memory map[string]map[string]string
}

func NewVm() *Vm {
  fmt.Println("init Ethereum VM")

  stackSize := uint(256)
  fmt.Println("stack size =", stackSize)

  return &Vm{make(map[string]string), 0, make(map[string]map[string]string)}
}

func (vm *Vm) RunTransaction(tx *Transaction, cb TxCallback) {
  fmt.Printf(`
# processing Tx (%v)
# fee = %f, ops = %d, sender = %s, value = %d
`, tx.addr, float32(tx.fee) / 1e8, len(tx.data), tx.sender, tx.value)

  vm.stack = make(map[string]string)
  vm.stack["0"] = tx.sender
  vm.stack["1"] = "100"  //int(tx.value)
  vm.stack["1"] = "1000" //int(tx.fee)

  //vm.memory[tx.addr] = make([]int, 256)
  vm.memory[tx.addr] = make(map[string]string)

  // Define instruction 'accessors' for the instruction, which makes it more readable
  // also called register values, shorthanded as Rx/y/z. Memory address are shorthanded as Mx/y/z.
  // Instructions are shorthanded as Ix/y/z
  x := 0; y := 1; z := 2; //a := 3; b := 4; c := 5
out:
  for vm.iptr < len(tx.data) {
    // The base big int for all calculations. Use this for any results.
    base := new(big.Int)
    // XXX Should Instr return big int slice instead of string slice?
    op, args, _ := Instr(tx.data[vm.iptr])

    fmt.Printf("%-3d %d %v\n", vm.iptr, op, args)

    opType     := OpType(tNorm)
    // Determine the op type (used for calculating fees by the block manager)
    switch op {
    case oEXTRO, oBALANCE:
      opType = tExtro
    case oSHA256, oRIPEMD160, oECMUL, oECADD: // TODO add rest
      opType = tCrypto
    }

    // If the callback yielded a negative result abort execution
    if !cb(opType) { break out }

    nptr := vm.iptr
    switch op {
    case oSTOP:
      fmt.Println("exiting (oSTOP), idx =", nptr)

      break out
    case oADD:
      // (Rx + Ry) % 2 ** 256
      base.Add(Big(vm.stack[args[ x ]]), Big(vm.stack[args[ y ]]))
      base.Mod(base, big.NewInt(int64(math.Pow(2, 256))))
      // Set the result to Rz
      vm.stack[args[ z ]] = base.String()
    case oSUB:
      // (Rx - Ry) % 2 ** 256
      base.Sub(Big(vm.stack[args[ x ]]), Big(vm.stack[args[ y ]]))
      base.Mod(base, big.NewInt(int64(math.Pow(2, 256))))
      // Set the result to Rz
      vm.stack[args[ z ]] = base.String()
    case oMUL:
      // (Rx * Ry) % 2 ** 256
      base.Mul(Big(vm.stack[args[ x ]]), Big(vm.stack[args[ y ]]))
      base.Mod(base, big.NewInt(int64(math.Pow(2, 256))))
      // Set the result to Rz
      vm.stack[args[ z ]] = base.String()
    case oDIV:
      // floor(Rx / Ry)
      base.Div(Big(vm.stack[args[ x ]]), Big(vm.stack[args[ y ]]))
      // Set the result to Rz
      vm.stack[args[ z ]] = base.String()
    case oSET:
      // Set the (numeric) value at Iy to Rx
      vm.stack[args[ x ]] = args[ y ]
    case oLD:
      // Load the value at Mx to Ry
      vm.stack[args[ y ]] = vm.memory[tx.addr][vm.stack[args[ x ]]]
    case oLT:
      cmp := Big(vm.stack[args[ x ]]).Cmp( Big(vm.stack[args[ y ]]) )
      // Set the result as "boolean" value to Rz
      if  cmp < 0 { // a < b
        vm.stack[args[ z ]] = "1"
      } else {
        vm.stack[args[ z ]] = "0"
      }
    case oJMP:
      // Set the instruction pointer to the value at Rx
      ptr, _ := strconv.Atoi( vm.stack[args[ x ]] )
      nptr = ptr
    case oJMPI:
      // Set the instruction pointer to the value at Ry if Rx yields true
      if vm.stack[args[ x ]] != "0" {
        ptr, _ := strconv.Atoi( vm.stack[args[ y ]] )
        nptr = ptr
      }
    default:
      fmt.Println("Error op", op)
      break
    }

    if vm.iptr == nptr {
      vm.iptr++
    } else {
      vm.iptr = nptr
      fmt.Println("... JMP", nptr, "...")
    }
  }
  fmt.Println("# finished processing Tx\n")
}