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Allow testing recovery with an initialized device

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This would allow safe mnemonic validation by using a dry-run flag.
pull/25/head
Roman Zeyde 7 years ago committed by Pavol Rusnak
parent db19dd1306
commit db7915e946
No known key found for this signature in database
GPG Key ID: 91F3B339B9A02A3D
3 changed files with 86 additions and 26 deletions
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10
firmware/fsm.c
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@ -988,7 +988,12 @@ void fsm_msgEstimateTxSize(EstimateTxSize *msg)
void fsm_msgRecoveryDevice(RecoveryDevice *msg)
{
CHECK_NOT_INITIALIZED
const bool dry_run = msg->has_dry_run ? msg->dry_run : false;
if (dry_run) {
CHECK_PIN
} else {
CHECK_NOT_INITIALIZED
}
CHECK_PARAM(!msg->has_word_count || msg->word_count == 12 || msg->word_count == 18 || msg->word_count == 24, _("Invalid word count"));
@ -1000,7 +1005,8 @@ void fsm_msgRecoveryDevice(RecoveryDevice *msg)
msg->has_label ? msg->label : 0,
msg->has_enforce_wordlist && msg->enforce_wordlist,
msg->has_type ? msg->type : 0,
msg->has_u2f_counter ? msg->u2f_counter : 0
msg->has_u2f_counter ? msg->u2f_counter : 0,
dry_run
);
}

100
firmware/recovery.c
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@ -44,6 +44,11 @@ static uint32_t word_count;
*/
static int awaiting_word = 0;
/* True if we should not write anything back to storage
* (can be used for testing seed for correctness).
*/
static bool dry_run;
/* True if we should check that seed corresponds to bip39.
*/
static bool enforce_wordlist;
@ -121,27 +126,73 @@ static void recovery_request(void) {
msg_write(MessageType_MessageType_WordRequest, &resp);
}
static bool is_same_mnemonic(const char *new_mnemonic) {
/* The execution time of the following code only depends on the
* (public) input. This avoids timing attacks.
*/
char diff = 0;
uint32_t i = 0;
for (; new_mnemonic[i]; i++) {
diff |= (storage.mnemonic[i] - new_mnemonic[i]);
}
diff |= storage.mnemonic[i];
return diff == 0;
}
/* Called when the last word was entered.
* Check mnemonic and send success/failure.
*/
static void recovery_done(void) {
uint32_t i;
strlcpy(storage.mnemonic, words[0], sizeof(storage.mnemonic));
char new_mnemonic[sizeof(storage.mnemonic)] = {0};
strlcpy(new_mnemonic, words[0], sizeof(new_mnemonic));
for (i = 1; i < word_count; i++) {
strlcat(storage.mnemonic, " ", sizeof(storage.mnemonic));
strlcat(storage.mnemonic, words[i], sizeof(storage.mnemonic));
strlcat(new_mnemonic, " ", sizeof(new_mnemonic));
strlcat(new_mnemonic, words[i], sizeof(new_mnemonic));
}
if (!enforce_wordlist || mnemonic_check(storage.mnemonic)) {
storage.has_mnemonic = true;
if (!enforce_wordlist) {
// not enforcing => mark storage as imported
storage.has_imported = true;
storage.imported = true;
if (!enforce_wordlist || mnemonic_check(new_mnemonic)) {
// New mnemonic is valid.
if (!dry_run) {
// Update mnemonic on storage.
storage.has_mnemonic = true;
strlcpy(storage.mnemonic, new_mnemonic, sizeof(new_mnemonic));
if (!enforce_wordlist) {
// not enforcing => mark storage as imported
storage.has_imported = true;
storage.imported = true;
}
storage_commit();
fsm_sendSuccess(_("Device recovered"));
} else {
// Inform the user about new mnemonic correctness (as well as whether it is the same as the current one).
const bool same_mnemonic = is_same_mnemonic(new_mnemonic);
if (same_mnemonic) {
layoutDialog(&bmp_icon_ok, NULL, _("Confirm"), NULL,
_("The mnemonic is"),
_("valid and matches"),
_("existing one."), NULL, NULL, NULL);
protectButton(ButtonRequestType_ButtonRequest_Other, true);
fsm_sendSuccess(_("Mnemonic is valid and matches existing one"));
} else {
layoutDialog(&bmp_icon_error, NULL, _("Confirm"), NULL,
_("The mnemonic is"),
_("valid but doesn't"),
_("match existing one."), NULL, NULL, NULL);
protectButton(ButtonRequestType_ButtonRequest_Other, true);
fsm_sendFailure(FailureType_Failure_DataError,
_("Mnemonic is valid but doesn't match existing one"));
}
}
storage_commit();
fsm_sendSuccess(_("Device recovered"));
} else {
storage_reset();
// New mnemonic is invalid.
if (!dry_run) {
storage_reset();
} else {
layoutDialog(&bmp_icon_error, NULL, _("Confirm"), NULL,
_("The mnemonic is"), _("invalid!"), NULL, NULL, NULL, NULL);
protectButton(ButtonRequestType_ButtonRequest_Other, true);
}
fsm_sendFailure(FailureType_Failure_DataError, _("Invalid mnemonic, are words in correct order?"));
}
awaiting_word = 0;
@ -369,24 +420,27 @@ void next_word(void) {
recovery_request();
}
void recovery_init(uint32_t _word_count, bool passphrase_protection, bool pin_protection, const char *language, const char *label, bool _enforce_wordlist, uint32_t type, uint32_t u2f_counter)
void recovery_init(uint32_t _word_count, bool passphrase_protection, bool pin_protection, const char *language, const char *label, bool _enforce_wordlist, uint32_t type, uint32_t u2f_counter, bool _dry_run)
{
if (_word_count != 12 && _word_count != 18 && _word_count != 24) return;
word_count = _word_count;
enforce_wordlist = _enforce_wordlist;
dry_run = _dry_run;
if (pin_protection && !protectChangePin()) {
fsm_sendFailure(FailureType_Failure_ActionCancelled, NULL);
layoutHome();
return;
}
if (!dry_run) {
if (pin_protection && !protectChangePin()) {
fsm_sendFailure(FailureType_Failure_ActionCancelled, NULL);
layoutHome();
return;
}
storage.has_passphrase_protection = true;
storage.passphrase_protection = passphrase_protection;
storage_setLanguage(language);
storage_setLabel(label);
storage_setU2FCounter(u2f_counter);
storage.has_passphrase_protection = true;
storage.passphrase_protection = passphrase_protection;
storage_setLanguage(language);
storage_setLabel(label);
storage_setU2FCounter(u2f_counter);
}
if ((type & RecoveryDeviceType_RecoveryDeviceType_Matrix) != 0) {
awaiting_word = 2;

2
firmware/recovery.h
Unescape View File

@ -23,7 +23,7 @@
#include <stdint.h>
#include <stdbool.h>
void recovery_init(uint32_t _word_count, bool passphrase_protection, bool pin_protection, const char *language, const char *label, bool _enforce_wordlist, uint32_t type, uint32_t u2f_counter);
void recovery_init(uint32_t _word_count, bool passphrase_protection, bool pin_protection, const char *language, const char *label, bool _enforce_wordlist, uint32_t type, uint32_t u2f_counter, bool _dry_run);
void recovery_word(const char *word);
void recovery_abort(void);
const char *recovery_get_fake_word(void);

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