[Patch] net: af_key: check encryption module availability consistency

[Thomas Bartschies <thomas.bartschies@cvk.de>]

Since the recent introduction supporting the SM3 and SM4 hash algos for IPsec, the kernel 
produces invalid pfkey acquire messages, when these encryption modules are disabled. This 
happens because the availability of the algos wasn't checked in all necessary functions. 
This patch adds these checks.

Signed-off-by: Thomas Bartschies <thomas.bartschies@cvk.de>

diff -uprN a/net/key/af_key.c b/net/key/af_key.c
--- a/net/key/af_key.c	2022-05-09 09:16:33.000000000 +0200
+++ b/net/key/af_key.c	2022-05-13 13:51:58.286250337 +0200
@@ -2898,7 +2898,7 @@ static int count_ah_combs(const struct x
 			break;
 		if (!aalg->pfkey_supported)
 			continue;
-		if (aalg_tmpl_set(t, aalg))
+		if (aalg_tmpl_set(t, aalg) && aalg->available)
 			sz += sizeof(struct sadb_comb);
 	}
 	return sz + sizeof(struct sadb_prop);
@@ -2916,7 +2916,7 @@ static int count_esp_combs(const struct
 		if (!ealg->pfkey_supported)
 			continue;
 
-		if (!(ealg_tmpl_set(t, ealg)))
+		if (!(ealg_tmpl_set(t, ealg) && ealg->available))
 			continue;
 
 		for (k = 1; ; k++) {
@@ -2927,7 +2927,7 @@ static int count_esp_combs(const struct
 			if (!aalg->pfkey_supported)
 				continue;
 
-			if (aalg_tmpl_set(t, aalg))
+			if (aalg_tmpl_set(t, aalg) && aalg->available)
 				sz += sizeof(struct sadb_comb);
 		}
 	}