anti-DoS rounds count limits for blowfish and des crypt

all of the limits could use review, but err on the side of avoiding
excessive rounds for now.

src/misc/crypt_blowfish.c

@@ -625,7 +625,7 @@ static char *BF_crypt(const char *key, const char *setting,
 	}
 
 	count = (BF_word)1 << ((setting[4] - '0') * 10 + (setting[5] - '0'));
-	if (count < min || BF_decode(data.binary.salt, &setting[7], 16)) {
+	if (count < min || count > 2048 || BF_decode(data.binary.salt, &setting[7], 16)) {
 		return NULL;
 	}
 	BF_swap(data.binary.salt, 4);

src/misc/crypt_des.c

@@ -911,7 +911,7 @@ static char *_crypt_extended_r_uut(const char *_key, const char *_setting, char
 				return NULL;
 			count |= value << (i - 1) * 6;
 		}
-		if (!count)
+		if (!count || count > 262143)
 			return NULL;
 
 		for (i = 5, salt = 0; i < 9; i++) {