From 7ca15861dd70e72f242b2c0077b5678bae83ffad Mon Sep 17 00:00:00 2001 From: Matthew Holt Date: Thu, 2 Apr 2020 09:43:33 -0600 Subject: caddytls: Encode big.Int as string with JSON --- modules/caddytls/certselection.go | 29 +++++++++++++++++++++++++---- 1 file changed, 25 insertions(+), 4 deletions(-) (limited to 'modules') diff --git a/modules/caddytls/certselection.go b/modules/caddytls/certselection.go index 8a24034..0311f11 100644 --- a/modules/caddytls/certselection.go +++ b/modules/caddytls/certselection.go @@ -17,6 +17,7 @@ package caddytls import ( "crypto/tls" "crypto/x509" + "encoding/json" "fmt" "math/big" @@ -29,7 +30,7 @@ import ( // This was needed to solve https://github.com/caddyserver/caddy/issues/2588. type CustomCertSelectionPolicy struct { // The certificate must have one of these serial numbers. - SerialNumber []*big.Int `json:"serial_number,omitempty"` + SerialNumber []bigInt `json:"serial_number,omitempty"` // The certificate must have one of these organization names. SubjectOrganization []string `json:"subject_organization,omitempty"` @@ -57,7 +58,7 @@ nextChoice: if len(p.SerialNumber) > 0 { var found bool for _, sn := range p.SerialNumber { - if cert.Leaf.SerialNumber.Cmp(sn) == 0 { + if cert.Leaf.SerialNumber.Cmp(&sn.Int) == 0 { found = true break } @@ -120,5 +121,25 @@ nextChoice: return certmagic.DefaultCertificateSelector(hello, viable) } -// Interface guard -var _ certmagic.CertificateSelector = (*CustomCertSelectionPolicy)(nil) +// bigInt is a big.Int type that interops with JSON encodings as a string. +type bigInt struct{ big.Int } + +func (bi bigInt) MarshalJSON() ([]byte, error) { + return json.Marshal(bi.String()) +} + +func (bi *bigInt) UnmarshalJSON(p []byte) error { + if string(p) == "null" { + return nil + } + var stringRep string + err := json.Unmarshal(p, &stringRep) + if err != nil { + return err + } + _, ok := bi.SetString(stringRep, 10) + if !ok { + return fmt.Errorf("not a valid big integer: %s", p) + } + return nil +} -- cgit v1.2.3