From 3e6b4b6e364482a8197415e22e3c792835653864 Mon Sep 17 00:00:00 2001
From: Jordi Pinyana <jordi.pinyana.paga@gmail.com>
Date: Wed, 21 Jun 2023 18:45:09 +0200
Subject: [PATCH] api: /chain/dateToBlock fix overflow for big timestamps

---
 api/chain.go                       |  2 +-
 api/wallet.go                      |  8 ++++----
 vochain/vochaininfo/vochaininfo.go | 19 ++++++++++++-------
 3 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/api/chain.go b/api/chain.go
index 774a97a65..d0ecfd581 100644
--- a/api/chain.go
+++ b/api/chain.go
@@ -333,7 +333,7 @@ func (a *API) chainEstimateHeightHandler(msg *apirest.APIdata, ctx *httprouter.H
 		return err
 	}
 	data, err := json.Marshal(struct {
-		Height uint32 `json:"height"`
+		Height uint64 `json:"height"`
 	}{Height: height},
 	)
 	if err != nil {
diff --git a/api/wallet.go b/api/wallet.go
index e7f5fc9f9..4d397bc2a 100644
--- a/api/wallet.go
+++ b/api/wallet.go
@@ -309,7 +309,7 @@ func (a *API) walletElectionHandler(msg *apirest.APIdata, ctx *httprouter.HTTPCo
 	}
 
 	// Set startBlock and endBlock
-	var startBlock uint32
+	var startBlock uint64
 	// if start date is empty, do not attempt to parse it. Set startBlock to 0, starting the
 	// election immediately. Otherwise, ensure the startBlock is in the future
 	if !description.StartDate.IsZero() {
@@ -336,7 +336,7 @@ func (a *API) walletElectionHandler(msg *apirest.APIdata, ctx *httprouter.HTTPCo
 	if startBlock == 0 {
 		// If startBlock is set to 0 (process starts asap), set the blockcount to the desired
 		// end block, minus the expected start block of the process
-		blockCount = blockCount - uint32(a.vocinfo.Height()) + 3
+		blockCount = blockCount - uint64(a.vocinfo.Height()) + 3
 	}
 
 	// Set the envelope and process models
@@ -421,8 +421,8 @@ func (a *API) walletElectionHandler(msg *apirest.APIdata, ctx *httprouter.HTTPCo
 	// Build the process transaction
 	process := &models.Process{
 		EntityId:     wallet.Address().Bytes(),
-		StartBlock:   startBlock,
-		BlockCount:   blockCount,
+		StartBlock:   uint32(startBlock),
+		BlockCount:   uint32(blockCount),
 		CensusRoot:   root,
 		CensusURI:    &description.Census.URL,
 		Status:       models.ProcessStatus_READY,
diff --git a/vochain/vochaininfo/vochaininfo.go b/vochain/vochaininfo/vochaininfo.go
index 6061f8b84..a65b38d98 100644
--- a/vochain/vochaininfo/vochaininfo.go
+++ b/vochain/vochaininfo/vochaininfo.go
@@ -3,6 +3,7 @@ package vochaininfo
 import (
 	"context"
 	"fmt"
+	"math"
 	"sync"
 	"time"
 
@@ -58,27 +59,31 @@ func (vi *VochainInfo) BlockTimes() *[5]int32 {
 }
 
 // EstimateBlockHeight provides an estimation time for a future blockchain height number.
-func (vi *VochainInfo) EstimateBlockHeight(target time.Time) (uint32, error) {
+func (vi *VochainInfo) EstimateBlockHeight(target time.Time) (uint64, error) {
 	currentTime := time.Now()
 	// diff time in seconds
 	diffTime := target.Unix() - currentTime.Unix()
 
 	// block time in ms
 	times := vi.BlockTimes()
-	getMaxTimeFrom := func(i int) uint32 {
+	getMaxTimeFrom := func(i int) uint64 {
 		for ; i >= 0; i-- {
 			if times[i] != 0 {
-				return uint32(times[i])
+				return uint64(times[i])
 			}
 		}
 		return 10000 // fallback
 	}
 	inPast := diffTime < 0
 	absDiff := diffTime
+	// check diff is not too big
+	if absDiff > math.MaxUint64/1000 {
+		return 0, fmt.Errorf("target time %v is too far in the future", target)
+	}
 	if inPast {
 		absDiff = -absDiff
 	}
-	t := uint32(0)
+	t := uint64(0)
 	switch {
 	// if less than around 15 minutes missing
 	case absDiff < 900:
@@ -86,14 +91,14 @@ func (vi *VochainInfo) EstimateBlockHeight(target time.Time) (uint32, error) {
 	// if less than around 6 hours missing
 	case absDiff < 21600:
 		t = getMaxTimeFrom(3)
-	// if less than around 6 hours missing
+	// if more than around 6 hours missing
 	default:
 		t = getMaxTimeFrom(4)
 	}
 	// Multiply by 1000 because t is represented in seconds, not ms.
 	// Dividing t first can floor the integer, leading to divide-by-zero
-	currentHeight := uint32(vi.Height())
-	blockDiff := (uint32(absDiff*1000) / t)
+	currentHeight := uint64(vi.Height())
+	blockDiff := (uint64(absDiff*1000) / t)
 	if inPast {
 		if blockDiff > currentHeight {
 			return 0, fmt.Errorf("target time %v is before origin", target)