:white_check_mark: Check arbitrary len limit (#1283)

* Check arbitrary len limit

* Fix typo

diff --git a/api/miner.go b/api/miner.go
index 988456e..8607371 100644 (file)
--- a/api/miner.go
+++ b/api/miner.go
@@ -2,6 +2,7 @@ package api
 
 import (
        "context"
+       "strconv"
 
        chainjson "github.com/bytom/encoding/json"
        "github.com/bytom/errors"
@@ -33,7 +34,18 @@ func (a *API) getCoinbaseArbitrary() Response {
        return NewSuccessResponse(resp)
 }
 
+// setCoinbaseArbitrary add arbitary data to the reserved coinbase data.
+// check function createCoinbaseTx in mining/mining.go for detail.
+// arbitraryLenLimit is 107 and can be calculated by:
+//     maxHeight := ^uint64(0)
+//     reserved := append([]byte{0x00}, []byte(strconv.FormatUint(maxHeight, 10))...)
+//     arbitraryLenLimit := consensus.CoinbaseArbitrarySizeLimit - len(reserved)
 func (a *API) setCoinbaseArbitrary(ctx context.Context, req CoinbaseArbitrary) Response {
+       arbitraryLenLimit := 107
+       if len(req.Arbitrary) > arbitraryLenLimit {
+               err := errors.New("Arbitrary exceeds limit: " + strconv.FormatUint(uint64(arbitraryLenLimit), 10))
+               return NewErrorResponse(err)
+       }
        a.wallet.AccountMgr.SetCoinbaseArbitrary(req.Arbitrary)
        return a.getCoinbaseArbitrary()
 }