Questions tagged [key-image]
Questions about key images including how they are computed and how they are used to prevent the double spending of Monero
35
questions
3
votes
1answer
58 views
How does Monero verify a tx outputs key image?
I'm new to Monero and I'm trying to get to grips on transactions compared to BTC.
What I'm trying to understand is - what prevents a transaction using a completely random string for 'x' within I = xHp(...
1
vote
1answer
36 views
How to compute ringct multisignature key images? (Disambiguation of MRL005)
I'm looking at the multisignature scheme provided by MRL005 Section 4.4, and some things are unclear to me. I've attached a picture below of the expression for which I'm seeking some clarification.
...
3
votes
2answers
90 views
What is the size of the set of spent key images in Monero?
For research purposes, I want to know the following:
What is the exact size of the set of already spent key images and how it can be checked? Do we need to download the Monero blockchain to get the ...
1
vote
1answer
53 views
Problems in generating LSAG KeyImage
I am trying to generate LSAG KeyImage by myself in C which is K̃ = kπ*Hp(R).
And I take result of MiniNero as a reference..
def test_keyImage():
private_key = "...
2
votes
1answer
75 views
Why is a key image xHp(P), and not something simpler like Hs(x)?
I understand how ringCTs work and know that they require a key image of the private key of the input that is actually being spent. How is this created? Couldn’t you just hash the private key of the ...
3
votes
1answer
92 views
Function ge_fromfe_frombytes_vartime() step by step explanation?
Could somebody please explain how this function works step by step?
Why: I am programming the Monero wallet functions on a quite limited platform with only some inbuilt cryptographic primitives. I ...
3
votes
1answer
100 views
Help needed with calculating a key image
I am working on monero synchronization on an ARM cortex m4 microcontroller and I got stuck with computing key image.
As a testing data I created a fresh wallet A and a fresh wallet B. I funded wallet ...
1
vote
1answer
53 views
Sent some monero with the cli using the transfer command. How can I get the key to view proof that I sent it using an monero explorer?
I did a transfer using the cli and now I want to view it in the https://xmrchain.net explorer. What do I need from me to decode the outputs so I can prove that I sent it? And what commands do I need ...
1
vote
2answers
64 views
How is the number of key images for a transaction selected?
I see that there are a few transactions that have many key images for each of the 11 ring members. But there are also a few with a lesser number of key images. How does this happen?
2
votes
1answer
139 views
Key Image and Ring Member
When were counting the number of ring signatures for a certain transaction do we count the number of key images or ring members of each key image?
1
vote
1answer
60 views
Does the Key Image leak privacy information?
If I Sign two different transactions with the same private key and send it to the same node. Would this node now be able to know which member of the ring is trying to sign?
As I believe the public ...
1
vote
1answer
224 views
The entire lifecycle of an XMR transaction with RingCT
I'm trying to understand the data structure in monerod and create a simple workflow for a transaction's life cycle.
It doesn't look like this has been done post-RingCT activation, and I see a lot of ...
1
vote
2answers
90 views
Can monero include actual spent input as previous transaction output?
Let's take we have two transactions. In the first transaction, it has 1 input with zero mixins and 3 outputs(stealth addresses). The second transaction has 1 input with one mixins and 2 outputs. Here ...
2
votes
1answer
89 views
How does key images work when you create a transaction using two or more of your previously unspent transaction outputs?
I've read key images are the critical element in Monero to avoid double spends.
I think I understand how it works when you are using only one of your previously unspent transaction outputs to create ...
1
vote
1answer
201 views
What keys are being used to create the key image and how is it verified?
So i'm trying to pin this down since yesterday and i simply cannot find a definite answer. Read dozens of posts and few papers specifically on this topic and while i developed a "belief" that it has ...
3
votes
1answer
117 views
Detecting the real output in ring signature
I have a strange question about the relation of P_i (stealth addresses in ring signature) with x (the one-time private key).
Suppose Alice wants to spend P_1 with her spend private key (x) and we ...
0
votes
1answer
107 views
wallet cli v0.12 : “ Error : Failed to import Key images”
I've already created some view only wallet using --generate-from-view-key and importing key images, but today i've an issue doing this last step with Wallet cli v0.12.
I've the following message when ...
4
votes
2answers
396 views
Understanding MLSAG in Monero transaction
This is a followup question to Understanding the structure of Monero transaction with emphasis on the MLSAG part.
Here's the transaction's structure again given with print_tx ...
2
votes
1answer
246 views
Is it easily provable by a third party that the key image used in a transaction is associated with the spent output without revealing the (P,I) pair?
What I'm getting at is I'd like to know how the Monero network can know that a key image used in a transaction is not either forged (probably an easy answer) or created from a different output owned ...
9
votes
1answer
722 views
How do key images really work?
I have the following questions regarding the equation I=xHp(P):
What is the hash function Hp?
How can we know that Hp(P) is a point on the Ed25519 curve? Or is it not?
Is the value I published with ...
9
votes
3answers
4k views
How does the recent patched key image exploit work in practice?
For more info https://getmonero.org/2017/05/17/disclosure-of-a-major-bug-in-cryptonote-based-currencies.html This has been patched months ago and was never exploited which can be proven by running a ...
4
votes
2answers
238 views
Key-image generation: What does p signify in I = xHp(P)?
According to the CN whitepaper key image I is generated thusly:
I = xHp(P)
I understand P is the one-time public key for the transaction, x the corresponding private key and H a deterministic hash ...
5
votes
3answers
854 views
Is making a key image public equal to giving the monero in that output away?
So I read about proving your balance to an auditor, and someone suggested that you can share your view key, exposing all outputs that you received on that address.
If you then give out all key images ...
4
votes
1answer
168 views
Can an output be used as a decoy after it has been spent?
The title of the question is probably specific enough, but I'll give more color anyway.
Here's a quick timeline.
I received output A a year ago.
In the last year, output A has been a decoy in 3 ...
3
votes
2answers
142 views
How can I check if a key image has been imported into a view wallet?
How can I check if a key image has been successfully imported into a view wallet, particularly a cold wallet that has never spent any of the funds it has received?
10
votes
1answer
172 views
Is it safe to share my key images with other people?
Let's say I run a charity that wants to show people how much money comes in and out of my Monero wallet. If I export the key images, is it safe to publish them on my website, or does doing so open up ...
6
votes
1answer
461 views
What signature prevents me from spending others' coins?
In passive mixing, the monero wallet finds n other parties and forms a ring signature that proves the signer is one of the parties in the ring, and hence entitled to spend from one of the accounts ...
3
votes
1answer
99 views
bad balanced CURRENCY_BLOCK_GRANTED_FULL_REWARD_ZONE constant
I have seen several Boolberry users report a wallet and daemon error similar to this one:
Wallet:
Error: transaction was rejected by daemon with status "Failed"
Daemon:
Transaction with id= ...
16
votes
3answers
5k views
What is a key image?
When a transaction is made with monero there is a 'key image' in the transaction info. what is this exactly? is it like the diffie-hellman exchange to create the one time addresses?
5
votes
1answer
334 views
What is the deterministic hash to EC function used to construct the key image?
Ring signatures alone would allow double spending, so Monero (as a result of following the CrpytoNote whitepaper) has to use a 'key image', which is the same across identical transactions and hence ...
1
vote
1answer
146 views
Trezor firmware, private view key, key image and privacy
It is my understanding that the Monero trezor firmware uses the private view key.
This might lead to some privacy concerns.
I have read that key image can be used to check balance of a paperwallet.
...
4
votes
1answer
481 views
What are the “ingredients” of a key image?
This is a scenario I've come up with to help me understand key images.
Let's say I have Wallet 1 and Wallet 2. Wallet 1 has TXO A and TXO B. I send TXO A and TXO B as inputs to Wallet 2. TXO B was ...
5
votes
2answers
1k views
Can the import\export key images command can be used to check the balance of a paperwallet?
The import/export key images command can be used to check the balance of a view only wallet.
But is there a way to use it to check the balance of an already set up Paperwallet?
Is it possible to get ...
7
votes
3answers
217 views
Does publishing view key and key images give the auditor the information on where I sent the funds?
I see here that it's possible to provide information to an auditor to prove the balance at a certain point in time (block height). Would this tell the auditor to where were the funds were sent? Based ...
19
votes
1answer
1k views
Can I fake a balance by giving the view key to an auditor but omitting some transactions and key images?
The viewkey can be used to see the outputs sent to my address, but not the outputs I generate when sending monero. If I need to know the balance I also need the private spendkey. It is suggested that ...
