adds salt

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Vitor Pamplona 2024-09-15 14:16:02 -04:00
parent d60412c81f
commit c47f5c0513

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76.md
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@ -6,13 +6,13 @@ Relay Read Permissions
`draft` `optional` `draft` `optional`
Tag names `rp` (read permission) and `prp` (probabilistic read permission) define which keys are authorized to download an event from the relay. Tags `rp` (read permission) and `prp` (probabilistic read permission) specify which keys are authorized to download an event from the relay.
Events with an `rp` or `prp` require AUTH to be downloaded. Events tagged with `rp` or `prp` require AUTH for download.
## Read Permission ## Read Permission
The `rp` tag takes a pubkey. Multiple `rp` tags represent a logical OR. The `rp` tag takes a pubkey in lowercase hex as value.
```json ```json
["rp", "<pubkey1>"] ["rp", "<pubkey1>"]
@ -20,27 +20,28 @@ The `rp` tag takes a pubkey. Multiple `rp` tags represent a logical OR.
["rp", "<pubkey3>"] ["rp", "<pubkey3>"]
``` ```
Relays MUST check if the authed user is one of the keys in the `rp` before sending the event to the client. When responding to `REQ`s, if an event contains `rp` tags, relays MUST verify that the authenticated user is either the event's author or one of the keys in the `rp` set before delivering it to the client.
## Probabilistic Read Permissions ## Probabilistic Read Permissions
Probabilistic permissions use bloom filters of a set of authorized pubkeys. They are represented by a colon-separated value with: Probabilistic permissions are implemented using Bloom filters that represent a set of authorized pubkeys. These permissions are expressed as a colon-separated value comprising:
1. the number of bits in the bit array 1. the number of bits in the bit array,
2. the number of hashing rounds used by the filter 2. the number of hash rounds applied, and
3. the bit array in Base64. 3. the bit array encoded in Base64.
4. the salt encoded in Base64.
```json ```json
["prp", "<bits>:<rounds>:<base64>"] ["prp", "<bits>:<rounds>:<base64>:<salt>"]
``` ```
Bloom filters MUST use `SHA256` functions of the key + iterating index as the pseudocode below demonstrates: Bloom filters MUST use `SHA256` functions applied to the concatenation of the key, salt, and index, as demonstrated in the pseudocode below:
```js ```js
class BloomFilter(size: Int, rounds: Int, buffer: ByteArray) { class BloomFilter(size: Int, rounds: Int, buffer: ByteArray, salt: ByteArray) {
val bits = BitArray(buffer) val bits = BitArray(buffer)
fun bitIndex(value: ByteArray, index: Byte) { fun bitIndex(value: ByteArray, index: Byte) {
return BigInt(sha256(value || index)) % size return BigInt(sha256(value || salt || index)) % size
} }
fun add(pubkey: HexKey) { fun add(pubkey: HexKey) {
@ -64,26 +65,26 @@ class BloomFilter(size: Int, rounds: Int, buffer: ByteArray) {
} }
fun encode() { fun encode() {
return size + ":" + rounds + ":" + base64Encode(bits.toByteArray()) return size + ":" + rounds + ":" + base64Encode(bits.toByteArray()) + ":" + base64Encode(salt)
} }
fun decode(str: String): BloomFilter { fun decode(str: String): BloomFilter {
val parts = str.split(":") val [sizeStr, roundsStr, bufferB64, saltB64] = str.split(":")
return BloomFilter(parts[0].toInt(), parts[1].toInt(), base64Decode(parts[2])) return BloomFilter(sizeStr.toInt(), roundsStr.toInt(), base64Decode(bufferB64), base64Decode(saltB64))
} }
} }
``` ```
Relays MUST check if the authed user is in the filter before returning the event. When responding to `REQ`s, if an event contains `prp` tags, relays MUST verify that the authenticated user is either the event's author or matches any of the filters before delivering it to the client.
Multiple `prp` tags represent a logical OR. If both `rp` and `prp` tags are present, the authenticated user MUST either be in the `rp` set or match any `prp` filter.
### Test cases ### Test cases
The filter below has 100 bits, with 10 rounds of hashes that should be able to match 10,000,000 keys without a single false positive. The filter below has 100 bits and uses 10 rounds of hashing, which should be capable of handling up to 10,000,000 keys without producing any false positives.
```json ```json
["prp", "100:10:QGKCgBEBAAhIAApO"] ["prp", "100:10:AAAkAQANcYQFCQoB:hZkZYqqdxcE="]
``` ```
It includes keys `ca29c211f1c72d5b6622268ff43d2288ea2b2cb5b9aa196ff9f1704fc914b71b` and `460c25e682fda7832b52d1f22d3d22b3176d972f60dcdc3212ed8c92ef85065c` It includes keys `ca29c211f1c72d5b6622268ff43d2288ea2b2cb5b9aa196ff9f1704fc914b71b` and `460c25e682fda7832b52d1f22d3d22b3176d972f60dcdc3212ed8c92ef85065c`