diff --git a/src/sbbs3/ssl.c b/src/sbbs3/ssl.c
index 00d5e9db3f673eb034931ddb1953ccf94c336156..0accf74e2d15c3b695637d6acf1d854cf4949811 100644
--- a/src/sbbs3/ssl.c
+++ b/src/sbbs3/ssl.c
@@ -31,7 +31,7 @@ char* DLLCALL get_crypt_error(CRYPT_SESSION sess)
 	return get_crypt_attribute(sess, CRYPT_ATTRIBUTE_ERRORMESSAGE);
 }
 
-static bool get_error_string(int status, CRYPT_SESSION sess, char *estr, char *file, int line)
+static bool get_error_string(int status, CRYPT_SESSION sess, char estr[SSL_ESTR_LEN], char *file, int line)
 {
 	char	*emsg;
 
@@ -50,7 +50,7 @@ static bool get_error_string(int status, CRYPT_SESSION sess, char *estr, char *f
 
 #define DO(x)	get_error_string(x, ssl_context, estr, __FILE__, __LINE__)
 
-CRYPT_CONTEXT DLLCALL get_ssl_cert(scfg_t *cfg, char *estr)
+CRYPT_CONTEXT DLLCALL get_ssl_cert(scfg_t *cfg, char estr[SSL_ESTR_LEN])
 {
 	CRYPT_KEYSET		ssl_keyset;
 	CRYPT_CONTEXT		ssl_context;
diff --git a/src/sbbs3/ssl.h b/src/sbbs3/ssl.h
index 365adaa0a795693c4f6c9b33f8487026762211f0..336df99efbafcef554a691b524131b368f4ac0a1 100644
--- a/src/sbbs3/ssl.h
+++ b/src/sbbs3/ssl.h
@@ -36,7 +36,7 @@ extern "C" {
 DLLEXPORT void DLLCALL free_crypt_attrstr(char *attr);
 DLLEXPORT char* DLLCALL get_crypt_attribute(CRYPT_SESSION sess, C_IN CRYPT_ATTRIBUTE_TYPE attr);
 DLLEXPORT char* DLLCALL get_crypt_error(CRYPT_SESSION sess);
-DLLEXPORT CRYPT_CONTEXT DLLCALL get_ssl_cert(scfg_t *cfg, char *estr);
+DLLEXPORT CRYPT_CONTEXT DLLCALL get_ssl_cert(scfg_t *cfg, char estr[SSL_ESTR_LEN]);
 
 #if defined(__cplusplus)
 }