gpg: default to AES-256.

* g10/main.h (DEFAULT_CIPHER_ALGO): Prefer AES256 by default.

--

It's 2017, and pretty much everyone has AES-256 available.  Symmetric
crypto is also rarely the bottleneck (asymmetric crypto is much more
expensive).  AES-256 provides some level of protection against
large-scale decryption efforts, and longer key lengths provide a hedge
against unforseen cryptanalysis.

Signed-off-by: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
(cherry picked from commit 73ff075204df09db5248170a049f06498cdbb7aa)

Gbp-Pq: Topic from-master
Gbp-Pq: Name gpg-default-to-AES-256.patch

diff --git a/g10/main.h b/g10/main.h
index 389a557fc0c39c322b64f9b21f6e4f930fa934f9..6f93de98d48272be474432dad7eb38b3c91bcb59 100644 (file)
--- a/g10/main.h
+++ b/g10/main.h
@@ -31,7 +31,9 @@
    (i.e. uncompressed) rather than 1 (zip).  However, the real world
    issues of speed and size come into play here. */
 
-#if GPG_USE_AES128
+#if GPG_USE_AES256
+# define DEFAULT_CIPHER_ALGO     CIPHER_ALGO_AES256
+#elif GPG_USE_AES128
 # define DEFAULT_CIPHER_ALGO     CIPHER_ALGO_AES
 #elif GPG_USE_CAST5
 # define DEFAULT_CIPHER_ALGO     CIPHER_ALGO_CAST5