couldn't recover public key from signature

[GoldRat]

I'm trying to buy AURA, using C# (API call "order"). But it returns:
{"error":"couldn't recover public key from signature"}
Please help me to find out on which step I've mistaken.

Wallet: 0x351296f44a5bf3f05eaa7d78a560f50dd736b728
Private key: 0xce8291ae3e3f6db1f7d763fa543c1aa7c76080f69880d695bf131f4ca7bde67a

This is arguments:
"contractAddress":"0x2a0c0dbecc7e4d658f48e01e3fa353f44050c208",
"tokenBuy":"0xcdcfc0f66c522fd086a1b725ea3c0eeb9f9e8814",
"amountBuy":"139611895000864697098",
"tokenSell":"0x0000000000000000000000000000000000000000",
"amountSell":"40000000000000000",
"expires":10000,
"nonce":2,
"address":"0x351296f44a5bf3f05eaa7d78a560f50dd736b728"

2. This is arguments string in hex:
   0x2a0c0dbecc7e4d658f48e01e3fa353f44050c208cdcfc0f66c522fd086a1b725ea3c0eeb9f9e8814000000000000000000000000000000000000000000000007918116cec9acab0a0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000008e1bc9bf04000000000000000000000000000000000000000000000000000000000000000027100000000000000000000000000000000000000000000000000000000000000002351296f44a5bf3f05eaa7d78a560f50dd736b728

3. This is the hash of arguments string (raw):
   0x42829b360851b370442abe990de6aa4719918c887f172f1ad7f8415f6b0430ba

4. This is the hash of raw with prefix \x19Ethereum Signed Message:\n32 (salted):
   0x1481258241d0bb45803c5efc22caaaf6d9301aff5b19fe8e119936cf0e77aa94

5. This is API call properties with signature:

{"contractAddress":"0x2a0c0dbecc7e4d658f48e01e3fa353f44050c208",
"tokenBuy":"0xcdcfc0f66c522fd086a1b725ea3c0eeb9f9e8814",
"amountBuy":"139611895000864697098",
"tokenSell":"0x0000000000000000000000000000000000000000",
"amountSell":"40000000000000000",
"expires":10000,
"nonce":2,
"address":"0x351296f44a5bf3f05eaa7d78a560f50dd736b728",
"v":27,
"r":"0x02edb1229ffd4f53b17c41bd016d1846c21774cc6f74f1863d11ab7cb62e9f55",
"s":"0x035fa7351c3c4d2fbddd6d9248e1295b21df1d8b0d554fa744cb0e406db046a7"}

I also will be very grateful for the example similar to the above with right values.

[GoldRat]

Looks like the developers abandoned IDEX API project. If so then remove the link to here from https://idex.market

[fubar]

Hi @GoldRat, did you get this sorted out? We don't have C# code samples, but in case it helps, here is what it would look like in JS:

const { soliditySha3 } = require('web3-utils');
const {
  hashPersonalMessage,
  bufferToHex,
  toBuffer,
  ecsign,
} = require('ethereumjs-util');
const { mapValues } = require('lodash');

const args = {
  "contractAddress": '0x2a0c0dbecc7e4d658f48e01e3fa353f44050c208',
  "tokenBuy": "0xcdcfc0f66c522fd086a1b725ea3c0eeb9f9e8814",
  "amountBuy": "139611895000864697098",
  "tokenSell": "0x0000000000000000000000000000000000000000",
  "amountSell": "40000000000000000",
  "address": "0x351296f44a5bf3f05eaa7d78a560f50dd736b728",
  "nonce": 2,
  "expires": 10000,
}

const raw = soliditySha3({
  t: 'address',
  v: args.contractAddress
}, {
  t: 'address',
  v: args.tokenBuy
}, {
  t: 'uint256',
  v: args.amountBuy
}, {
  t: 'address',
  v: args.tokenSell
}, {
  t: 'uint256',
  v: args.amountSell
}, {
  t: 'uint256',
  v: args.expires
}, {
  t: 'uint256',
  v: args.nonce
}, {
  t: 'address',
  v: args.address
});
const salted = hashPersonalMessage(toBuffer(raw));
const vrs = mapValues(ecsign(salted, toBuffer('0xce8291ae3e3f6db1f7d763fa543c1aa7c76080f69880d695bf131f4ca7bde67a')), (value, key) => key === 'v' ? value : bufferToHex(value));

delete args.contractAddress;
const args2 = Object.assign(args, vrs);
console.log(JSON.stringify(args2));

Which produces this request payload:

{
  "tokenBuy": "0xcdcfc0f66c522fd086a1b725ea3c0eeb9f9e8814",
  "amountBuy": "139611895000864697098",
  "tokenSell": "0x0000000000000000000000000000000000000000",
  "amountSell": "40000000000000000",
  "address": "0x351296f44a5bf3f05eaa7d78a560f50dd736b728",
  "nonce": 2,
  "expires": 10000,
  "r": "0x50573d44812198c38d03fc815026c8c85669a43bcade519f44440acaaf2ab2be",
  "s": "0x3136be5df241628bcafb845aea2c9b4d6e5d1bb87bc410af228e4d503ec39134",
  "v": 28
}

You can use this script to output any of the data points in the calculations and compare with the ones you've mentioned. In case you're new to JS, install node.js, copy and paste the above code into a file called something like order.js, then run:

npm install web3-utils ethereumjs-util lodash
node order.js

Also, as I'm sure you're aware, you should never hand out your private key, so don't use this wallet for real trading.

Cheers, Phil