From: Antonio Quartulli <a@unstable.cc>
Date: Sun, 10 Nov 2019 13:35:24 +0000 (+0100)
Subject: auth.c: make cast explicit in the crypto API
X-Git-Tag: v2.5_beta1~240
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=6c7b41c6536b221b1e2bc26a26ae6814a71d69e8;p=thirdparty%2Fopenvpn.git

auth.c: make cast explicit in the crypto API

mbedtls_md_get_size() returns unsigned char, while EVP_MD_size() returns
int. Results coming from both functions are normally in a uint8_t member
of the key_type struct, because it is known that 8bits are enough (also
for EVP_MD_size()).

This unexpected cast can, however, trigger unsolicited warnings.
Make the cast explicit by changing the return value of our crypto API.

Reported-by: Arne Schwabe <arne@rfc2549.org>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Acked-by: Arne Schwabe <arne@rfc2549.org>
Message-Id: <20191110133525.6069-2-a@unstable.cc>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg19093.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>
---

diff --git a/src/openvpn/crypto_backend.h b/src/openvpn/crypto_backend.h
index d119442f0..1d206a8ce 100644
--- a/src/openvpn/crypto_backend.h
+++ b/src/openvpn/crypto_backend.h
@@ -526,7 +526,7 @@ const char *md_kt_name(const md_kt_t *kt);
  *
  * @return              Message digest size, in bytes, or 0 if ctx was NULL.
  */
-int md_kt_size(const md_kt_t *kt);
+unsigned char md_kt_size(const md_kt_t *kt);
 
 
 /*
diff --git a/src/openvpn/crypto_mbedtls.c b/src/openvpn/crypto_mbedtls.c
index 648a988e8..3e77fa9ee 100644
--- a/src/openvpn/crypto_mbedtls.c
+++ b/src/openvpn/crypto_mbedtls.c
@@ -823,7 +823,7 @@ md_kt_name(const mbedtls_md_info_t *kt)
     return mbedtls_md_get_name(kt);
 }
 
-int
+unsigned char
 md_kt_size(const mbedtls_md_info_t *kt)
 {
     if (NULL == kt)
diff --git a/src/openvpn/crypto_openssl.c b/src/openvpn/crypto_openssl.c
index 520e40ee3..a81dcfd82 100644
--- a/src/openvpn/crypto_openssl.c
+++ b/src/openvpn/crypto_openssl.c
@@ -930,10 +930,10 @@ md_kt_name(const EVP_MD *kt)
     return EVP_MD_name(kt);
 }
 
-int
+unsigned char
 md_kt_size(const EVP_MD *kt)
 {
-    return EVP_MD_size(kt);
+    return (unsigned char)EVP_MD_size(kt);
 }