Both those with a 2-byte hash (instead of SHA1 or an AEAD authentication
tag) and those without an S2K specifier (i.e., using MD5 for S2K) -
support for the latter was already broken.
Vulnerabilities can arise not just from generating keys like this, but
from using them as well (if an attacker can tamper with them), hence why
we're removing support.
This function checks whether the private and public key parameters
of the primary key match.
This check is necessary when using your own private key to encrypt
data if the private key was stored on an untrusted medium, and
trust is derived from being able to decrypt the private key.
This also has the effect that we only throw on them when trying to use
the key, instead of when parsing it, and that we don't throw when the
authorized revocation key is specified in a separate direct-key
signature instead of a User ID self-signature (the spec only specifies
including it in a direct-key signature, so that means that we
effectively don't reject them anymore. This is because users that
wanted to use the key, could remove this separate signature, anyway.)
Also, when generating RSA keys in JS, generate them with p < q, as per
the spec.
Also, when generating RSA keys using Web Crypto or Node crypto, swap the
generated p and q around, so that will satisfy p < q in most browsers
(but not old Microsoft Edge, 50% of the time) and so that we can use the
generated u coefficient (p^-1 mod q in OpenPGP, q^-1 mod p in RFC3447).
Then, when signing and verifying, swap p and q again, so that the key
hopefully satisfies Safari's requirement that p > q, and so that we can
keep using u again.
As per the spec:
The one exception is that if the octet count is less than
the size of the salt plus passphrase, the full salt plus passphrase
will be hashed even though that is greater than the octet count.
This was broken in #922 (merged as part of #956).
This would cause GPG to be unable to parse unencrypted secret keys,
thinking they were encrypted.
rfc4880bis-08 hints at this requirement, saying:
o MPI of an integer representing the secret key, which is a scalar
of the public EC point.
Since scalar multiplication happens after masking the private key,
this implies that we should serialize the private key after masking,
as well.
This PR adds four config options to configure whether and how to load
indutny/elliptic: use_indutny_elliptic, external_indutny_elliptic,
indutny_elliptic_path and indutny_elliptic_fetch_options.
Also:
- Use tweetnacl.js instead of indutny/elliptic for curve25519 key generation
- Don't initialize indutny's curve25519, improving performance when using that curve
- Verify NIST signatures using Web Crypto instead of indutny/elliptic when not streaming
- Move KeyPair.sign/verify to ecdsa.js
- Move KeyPair.derive to ecdh.js
- Move keyFromPrivate and keyFromPublic to a new indutnyKey.js file
Keep supporting the old names as well though in `openpgp.generateKey`
and `getAlgorithmInfo`, but not in `openpgp.key.generate` (as it is
recommended that developers use `openpgp.generateKey` instead, and
it now throws when using `numBits` instead of `rsaBits`, so there's
no risk of silent key security downgrade).
The old names are now deprecated, and might be removed in v5.
