Displaying 5 results from an estimated 5 matches for "cipher_blocksize".
2023 Mar 29
2
ChaCha20 Rekey Frequency
...at
> would have on the security of the cipher as it's implemented. Especially the
> without-openssl internal implementation.
This is what I'm playing with at the moment:
diff --git a/cipher.c b/cipher.c
index c7664a3..ec6fa4f 100644
--- a/cipher.c
+++ b/cipher.c
@@ -150,6 +150,39 @@ cipher_blocksize(const struct sshcipher *c)
return (c->block_size);
}
+uint64_t
+cipher_rekey_blocks(const struct sshcipher *c)
+{
+ /*
+ * Chacha20-Poly1305 does not benefit from data-based rekeying,
+ * per "The Security of ChaCha20-Poly1305 in the Multi-user Setting",
+ * Degabriele, J. P.,...
2023 Mar 29
1
[EXTERNAL] Re: ChaCha20 Rekey Frequency
...at
> would have on the security of the cipher as it's implemented. Especially the
> without-openssl internal implementation.
This is what I'm playing with at the moment:
diff --git a/cipher.c b/cipher.c
index c7664a3..ec6fa4f 100644
--- a/cipher.c
+++ b/cipher.c
@@ -150,6 +150,39 @@ cipher_blocksize(const struct sshcipher *c)
return (c->block_size);
}
+uint64_t
+cipher_rekey_blocks(const struct sshcipher *c)
+{
+ /*
+ * Chacha20-Poly1305 does not benefit from data-based rekeying,
+ * per "The Security of ChaCha20-Poly1305 in the Multi-user Setting",
+ * Degabriele, J. P., Govinde...
2023 Mar 29
1
[EXTERNAL] Re: ChaCha20 Rekey Frequency
...s it's implemented. Especially
> the
> > without-openssl internal implementation.
>
> This is what I'm playing with at the moment:
>
> diff --git a/cipher.c b/cipher.c
> index c7664a3..ec6fa4f 100644
> --- a/cipher.c
> +++ b/cipher.c
> @@ -150,6 +150,39 @@ cipher_blocksize(const struct sshcipher *c)
> return (c->block_size);
> }
>
> +uint64_t
> +cipher_rekey_blocks(const struct sshcipher *c)
> +{
> + /*
> + * Chacha20-Poly1305 does not benefit from data-based rekeying,
> + * per "The Security of ChaCha20-Poly1305 in the Multi-user...
2023 Mar 29
1
ChaCha20 Rekey Frequency
I was wondering if there was something specific to the internal chacha20
cipher as opposed to OpenSSL implementation.
I can't just change the block size because it breaks compatibility. I
can do something like as a hack (though it would probably be better to
do it with the compat function):
if (strstr(enc->name, "chacha"))
*max_blocks = (u_int64_t)1 << (16*2);
2023 Mar 29
1
[EXTERNAL] Re: ChaCha20 Rekey Frequency
...as it's implemented. Especially
> the
> > without-openssl internal implementation.
>
> This is what I'm playing with at the moment:
>
> diff --git a/cipher.c b/cipher.c
> index c7664a3..ec6fa4f 100644
> --- a/cipher.c
> +++ b/cipher.c
> @@ -150,6 +150,39 @@ cipher_blocksize(const struct sshcipher *c)
> return (c->block_size);
> }
>
> +uint64_t
> +cipher_rekey_blocks(const struct sshcipher *c)
> +{
> + /*
> + * Chacha20-Poly1305 does not benefit from data-based rekeying,
> + * per "The Security of ChaCha20-Poly1305 in the Multi-user S...