ext/sodium: signing empty messages is fine

jedisct1 · jedisct1 · commit f64d00d684f6 · 2017-09-26T17:37:04.000+02:00
diff --git a/ext/sodium/libsodium.c b/ext/sodium/libsodium.c
@@ -1495,7 +1495,7 @@ PHP_FUNCTION(sodium_crypto_sign)
 		zend_throw_exception(sodium_exception_ce, "internal error", 0);
 		return;
 	}
-	if (msg_signed_real_len <= 0U || msg_signed_real_len >= SIZE_MAX ||
+	if (msg_signed_real_len < 0U || msg_signed_real_len >= SIZE_MAX ||
 		msg_signed_real_len > msg_signed_len) {
 		zend_string_free(msg_signed);
 		zend_throw_exception(sodium_exception_ce, "arithmetic overflow", 0);

Original file line number	Diff line number	Diff line change
`@@ -1495,7 +1495,7 @@ PHP_FUNCTION(sodium_crypto_sign)`
`1495`	`1495`	`zend_throw_exception(sodium_exception_ce, "internal error", 0);`
`1496`	`1496`	`return;`
`1497`	`1497`	`}`
`1498`		`- if (msg_signed_real_len <= 0U \|\| msg_signed_real_len >= SIZE_MAX \|\|`
	`1498`	`+ if (msg_signed_real_len < 0U \|\| msg_signed_real_len >= SIZE_MAX \|\|`
`1499`	`1499`	`msg_signed_real_len > msg_signed_len) {`
`1500`	`1500`	`zend_string_free(msg_signed);`
`1501`	`1501`	`zend_throw_exception(sodium_exception_ce, "arithmetic overflow", 0);`