PrivateCoffee/invidious
4
1
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions 2

Verify token signature in constant time, Run cheap checks first in token validation process (#1032)

Browse source 
* Verify token signature in constant time

To prevent timing side channel attacks

* Run cheap checks first in token validation process

Expensive checks such as the nonce lookup on the database or the
signature check can be run after cheap/fast checks.
This commit is contained in:
leonklingele 2020-03-02 17:04:36 +01:00 committed by GitHub
parent 72a4962fd0
commit 0d536d11e3
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
1 changed files with 15 additions and 14 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

29
src/invidious/helpers/tokens.cr
View file

@ -1,3 +1,5 @@
require "crypto/subtle"
def generate_token(email, scopes, expire, key, db)
session = "v1:#{Base64.urlsafe_encode(Random::Secure.random_bytes(32))}"
PG_DB.exec("INSERT INTO session_ids VALUES ($1, $2, $3)", session, email, Time.utc)
@ -76,14 +78,25 @@ def validate_request(token, session, request, key, db, locale = nil)
raise translate(locale, "Hidden field \"token\" is a required field")
end
if token["signature"] != sign_token(key, token)
raise translate(locale, "Invalid signature")
expire = token["expire"]?.try &.as_i
if expire.try &.< Time.utc.to_unix
raise translate(locale, "Token is expired, please try again")
end
if token["session"] != session
raise translate(locale, "Erroneous token")
end
scopes = token["scopes"].as_a.map { |v| v.as_s }
scope = "#{request.method}:#{request.path.lchop("/api/v1/auth/").lstrip("/")}"
if !scopes_include_scope(scopes, scope)
raise translate(locale, "Invalid scope")
end
if !Crypto::Subtle.constant_time_compare(token["signature"].to_s, sign_token(key, token))
raise translate(locale, "Invalid signature")
end
if token["nonce"]? && (nonce = db.query_one?("SELECT * FROM nonces WHERE nonce = $1", token["nonce"], as: {String, Time}))
if nonce[1] > Time.utc
db.exec("UPDATE nonces SET expire = $1 WHERE nonce = $2", Time.utc(1990, 1, 1), nonce[0])
@ -92,18 +105,6 @@ def validate_request(token, session, request, key, db, locale = nil)
end
end
scopes = token["scopes"].as_a.map { |v| v.as_s }
scope = "#{request.method}:#{request.path.lchop("/api/v1/auth/").lstrip("/")}"
if !scopes_include_scope(scopes, scope)
raise translate(locale, "Invalid scope")
end
expire = token["expire"]?.try &.as_i
if expire.try &.< Time.utc.to_unix
raise translate(locale, "Token is expired, please try again")
end
return {scopes, expire, token["signature"].as_s}
end