d-bis/app-ethereum
4
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Add Ledger signature checking for external plugins

Browse Source
This commit is contained in:
TamtamHero
2021-05-04 23:33:33 +02:00
committed by pscott
parent 46ebe6320a
commit 0bd5fa717e
4 changed files with 62 additions and 21 deletions
Download Patch File Download Diff File Expand all files Collapse all files

21
src_features/setExternalPlugin/cmd_setExternalPlugin.c
View File

@@ -1,6 +1,7 @@
#include "shared_context.h"
#include "apdu_constants.h"
#include "ui_flow.h"
#include "tokens.h"
#define CONTRACT_ADDR_SIZE 20
#define SELECTOR_SIZE 4
@@ -14,9 +15,12 @@ void handleSetExternalPlugin(uint8_t p1,
UNUSED(p1);
UNUSED(p2);
UNUSED(flags);
uint8_t pluginNameLength = *workBuffer++;
uint8_t hash[32];
cx_ecfp_public_key_t tokenKey;
uint8_t pluginNameLength = *workBuffer;
const size_t payload_size = 1 + pluginNameLength + CONTRACT_ADDR_SIZE + SELECTOR_SIZE;
if (dataLength < 1 || dataLength != 1 + pluginNameLength + CONTRACT_ADDR_SIZE + SELECTOR_SIZE) {
if (dataLength <= payload_size) {
THROW(0x6A80);
}
@@ -24,6 +28,19 @@ void handleSetExternalPlugin(uint8_t p1,
THROW(0x6A80);
}
// check Ledger's signature over the payload
cx_hash_sha256(workBuffer, payload_size, hash, sizeof(hash));
cx_ecfp_init_public_key(CX_CURVE_256K1,
LEDGER_SIGNATURE_PUBLIC_KEY,
sizeof(LEDGER_SIGNATURE_PUBLIC_KEY),
&tokenKey);
if(!cx_ecdsa_verify(&tokenKey, CX_LAST, CX_SHA256, hash, sizeof(hash), workBuffer+payload_size, dataLength-payload_size)){
PRINTF("Invalid external plugin signature %.*H\n", payload_size, workBuffer);
THROW(0x6A80);
}
// move on to the rest of the payload parsing
workBuffer++;
memmove(dataContext.tokenContext.pluginName, workBuffer, pluginNameLength);
dataContext.tokenContext.pluginName[pluginNameLength] = '\0';
workBuffer += pluginNameLength;