cosmos-sdk/x/auth/ante.go

91 lines
2.1 KiB
Go

package auth
import (
sdk "github.com/cosmos/cosmos-sdk/types"
)
func NewAnteHandler(accountMapper sdk.AccountMapper) sdk.AnteHandler {
return func(
ctx sdk.Context, tx sdk.Tx,
) (_ sdk.Context, _ sdk.Result, abort bool) {
// Deduct the fee from the fee payer.
// This is done first because it only
// requires fetching 1 account.
payerAddr := tx.GetFeePayer()
if payerAddr != nil {
payerAcc := accountMapper.GetAccount(ctx, payerAddr)
if payerAcc == nil {
return ctx,
sdk.ErrUnrecognizedAddress(payerAddr).Result(),
true
}
// TODO: Charge fee from payerAcc.
// TODO: accountMapper.SetAccount(ctx, payerAddr)
} else {
// TODO: Ensure that some other spam prevention is used.
}
var sigs = tx.GetSignatures()
// Assert that there are signatures.
if len(sigs) == 0 {
return ctx,
sdk.ErrUnauthorized("no signers").Result(),
true
}
// Ensure that sigs are correct.
var msg = tx.GetMsg()
var signerAddrs = msg.GetSigners()
var signerAccs = make([]sdk.Account, len(signerAddrs))
// Assert that number of signatures is correct.
if len(sigs) != len(signerAddrs) {
return ctx,
sdk.ErrUnauthorized("wrong number of signers").Result(),
true
}
// Check each nonce and sig.
// TODO Refactor out.
for i, sig := range sigs {
var signerAcc = accountMapper.GetAccount(ctx, signerAddrs[i])
signerAccs[i] = signerAcc
// If no pubkey, set pubkey.
if signerAcc.GetPubKey().Empty() {
err := signerAcc.SetPubKey(sig.PubKey)
if err != nil {
return ctx,
sdk.ErrInternal("setting PubKey on signer").Result(),
true
}
}
// Check and increment sequence number.
seq := signerAcc.GetSequence()
if seq != sig.Sequence {
return ctx,
sdk.ErrInvalidSequence("").Result(),
true
}
signerAcc.SetSequence(seq + 1)
// Check sig.
if !sig.PubKey.VerifyBytes(msg.GetSignBytes(), sig.Signature) {
return ctx,
sdk.ErrUnauthorized("").Result(),
true
}
// Save the account.
accountMapper.SetAccount(ctx, signerAcc)
}
ctx = WithSigners(ctx, signerAccs)
return ctx, sdk.Result{}, false // continue...
}
}