[PATCH v5 10/10] Makefile: discuss SHAttered in *_SHA{1,256} discussion

From

Ævar Arnfjörð Bjarmason <avarab@gmail.com>

Date

Nov 7, 2022, 21:23 UTC

Message-ID

<patch-v5-10.10-55d3751faea-20221107T211736Z-avarab@gmail.com>

In-Reply-To

<cover-v5-00.10-00000000000-20221107T211736Z-avarab@gmail.com>

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 Makefile | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/Makefile b/Makefile
index 7d0fa7adb61..91596bac4c0 100644
--- a/Makefile
+++ b/Makefile
@@ -481,6 +481,17 @@ include shared.mak
 #
 # === SHA-1 backend ===
 #
+# ==== Security ====
+#
+# Due to the SHAttered (https://shattered.io) attack vector on SHA-1
+# it's strongly recommended to use the sha1collisiondetection
+# counter-cryptanalysis library for SHA-1 hashing.
+#
+# If you know that you can trust the repository contents, or where
+# potential SHA-1 attacks are otherwise mitigated the other backends
+# listed in "SHA-1 implementations" are faster than
+# sha1collisiondetection.
+#
 # ==== Default SHA-1 backend ====
 #
 # If no *_SHA1 backend is picked, the first supported one listed in
@@ -525,6 +536,11 @@ include shared.mak
 #
 # === SHA-256 backend ===
 #
+# ==== Security ====
+#
+# Unlike SHA-1 the SHA-256 algorithm does not suffer from any known
+# vulnerabilities, so any implementation will do.
+#
 # ==== SHA-256 implementations ====
 #
 # Define OPENSSL_SHA256 to use the SHA-256 routines in OpenSSL.

-- 
2.38.0.1464.gea6794aacbc