[PATCH v2 1/4] crypto: set default initializer hmac/hash arrays to -1

["Daniel P. Berrangé" <berrange@redhat.com>]

The default static array initializer of 0 is not suitable for
the glib hash/hmac backends, as G_CHECKSUM_MD5 has a value of
0. Instead elements must be initialized to -1, but remembering
todo that as new algorithms are defined is errorprone. The
SM3 algorithm initializer is missing, leading to it being
mapped to MD5. This could potentially be a security flaw through
use of the wrong (much weaker) hashing algorithm, if a further
bug elsewhere didn't mask the issue.

Set a default array initializer so unlisted algorithms are
always set to -1 instead of 0.

Fixes: https://gitlab.com/qemu-project/qemu/-/work_items/4786
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
 crypto/hash-glib.c | 3 +--
 crypto/hmac-glib.c | 4 +---
 2 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/crypto/hash-glib.c b/crypto/hash-glib.c
index 809cef98aee..d915430f459 100644
--- a/crypto/hash-glib.c
+++ b/crypto/hash-glib.c
@@ -26,13 +26,12 @@
 
 
 static int qcrypto_hash_alg_map[QCRYPTO_HASH_ALGO__MAX] = {
+    [0 ... QCRYPTO_HASH_ALGO__MAX - 1] = -1,
     [QCRYPTO_HASH_ALGO_MD5] = G_CHECKSUM_MD5,
     [QCRYPTO_HASH_ALGO_SHA1] = G_CHECKSUM_SHA1,
-    [QCRYPTO_HASH_ALGO_SHA224] = -1,
     [QCRYPTO_HASH_ALGO_SHA256] = G_CHECKSUM_SHA256,
     [QCRYPTO_HASH_ALGO_SHA384] = G_CHECKSUM_SHA384,
     [QCRYPTO_HASH_ALGO_SHA512] = G_CHECKSUM_SHA512,
-    [QCRYPTO_HASH_ALGO_RIPEMD160] = -1,
 };
 
 gboolean qcrypto_hash_supports(QCryptoHashAlgo alg)
diff --git a/crypto/hmac-glib.c b/crypto/hmac-glib.c
index 1f17769c1c7..4453e0d5f06 100644
--- a/crypto/hmac-glib.c
+++ b/crypto/hmac-glib.c
@@ -18,13 +18,11 @@
 #include "hmacpriv.h"
 
 static int qcrypto_hmac_alg_map[QCRYPTO_HASH_ALGO__MAX] = {
+    [0 ... QCRYPTO_HASH_ALGO__MAX - 1] = -1,
     [QCRYPTO_HASH_ALGO_MD5] = G_CHECKSUM_MD5,
     [QCRYPTO_HASH_ALGO_SHA1] = G_CHECKSUM_SHA1,
     [QCRYPTO_HASH_ALGO_SHA256] = G_CHECKSUM_SHA256,
     [QCRYPTO_HASH_ALGO_SHA512] = G_CHECKSUM_SHA512,
-    [QCRYPTO_HASH_ALGO_SHA224] = -1,
-    [QCRYPTO_HASH_ALGO_SHA384] = -1,
-    [QCRYPTO_HASH_ALGO_RIPEMD160] = -1,
 };
 
 typedef struct QCryptoHmacGlib QCryptoHmacGlib;
-- 
2.56.0