Merge branch 'ky/imap-send-openssl-1.1.0' into maint

Upcoming OpenSSL 1.1.0 will break compilation b updating a few APIs
we use in imap-send, which has been adjusted for the change.

* ky/imap-send-openssl-1.1.0:
  configure: remove checking for HMAC_CTX_cleanup
  imap-send: avoid deprecated TLSv1_method()
  imap-send: check NULL return of SSL_CTX_new()
  imap-send: use HMAC() function provided by OpenSSL

Author: gitster

Makefile

@@ -355,9 +355,6 @@ all::
 #
 # Define HAVE_CLOCK_MONOTONIC if your platform has CLOCK_MONOTONIC in librt.
 #
-# Define NO_HMAC_CTX_CLEANUP if your OpenSSL is version 0.9.6b or earlier to
-# cleanup the HMAC context with the older HMAC_cleanup function.
-#
 # Define USE_PARENS_AROUND_GETTEXT_N to "yes" if your compiler happily
 # compiles the following initialization:
 #
@@ -1138,9 +1135,6 @@ ifndef NO_OPENSSL
 	ifdef NEEDS_CRYPTO_WITH_SSL
 		OPENSSL_LIBSSL += -lcrypto
 	endif
-	ifdef NO_HMAC_CTX_CLEANUP
-		BASIC_CFLAGS += -DNO_HMAC_CTX_CLEANUP
-	endif
 else
 	BASIC_CFLAGS += -DNO_OPENSSL
 	BLK_SHA1 = 1

compat/apple-common-crypto.h

@@ -3,12 +3,18 @@
 #define HEADER_HMAC_H
 #define HEADER_SHA_H
 #include <CommonCrypto/CommonHMAC.h>
-#define HMAC_CTX CCHmacContext
-#define HMAC_Init(hmac, key, len, algo) CCHmacInit(hmac, algo, key, len)
-#define HMAC_Update CCHmacUpdate
-#define HMAC_Final(hmac, hash, ptr) CCHmacFinal(hmac, hash)
-#define HMAC_CTX_cleanup(ignore)
 #define EVP_md5(...) kCCHmacAlgMD5
+/* CCHmac doesn't take md_len and the return type is void */
+#define HMAC git_CC_HMAC
+static inline unsigned char *git_CC_HMAC(CCHmacAlgorithm alg,
+		const void *key, int key_len,
+		const unsigned char *data, size_t data_len,
+		unsigned char *md, unsigned int *md_len)
+{
+	CCHmac(alg, key, key_len, data, data_len, md);
+	return md;
+}
+
 #if __MAC_OS_X_VERSION_MIN_REQUIRED >= 1070
 #define APPLE_LION_OR_NEWER
 #include <Security/Security.h>

configure.ac

@@ -970,10 +970,6 @@ AC_CHECK_LIB([iconv], [locale_charset],
                      [CHARSET_LIB=-lcharset])])
 GIT_CONF_SUBST([CHARSET_LIB])
 #
-# Define NO_HMAC_CTX_CLEANUP=YesPlease if HMAC_CTX_cleanup is missing.
-AC_CHECK_LIB([crypto], [HMAC_CTX_cleanup],
-	[], [GIT_CONF_SUBST([NO_HMAC_CTX_CLEANUP], [YesPlease])])
-#
 # Define HAVE_CLOCK_GETTIME=YesPlease if clock_gettime is available.
 GIT_CHECK_FUNC(clock_gettime,
 	[HAVE_CLOCK_GETTIME=YesPlease],

git-compat-util.h

@@ -279,9 +279,6 @@ extern char *gitdirname(char *);
 #endif
 #include <openssl/ssl.h>
 #include <openssl/err.h>
-#ifdef NO_HMAC_CTX_CLEANUP
-#define HMAC_CTX_cleanup HMAC_cleanup
-#endif
 #endif
 
 /* On most systems <netdb.h> would have given us this, but

imap-send.c

@@ -287,17 +287,20 @@ static int ssl_socket_connect(struct imap_socket *sock, int use_tls_only, int ve
 	SSL_library_init();
 	SSL_load_error_strings();
 
-	if (use_tls_only)
-		meth = TLSv1_method();
-	else
-		meth = SSLv23_method();
-
+	meth = SSLv23_method();
 	if (!meth) {
 		ssl_socket_perror("SSLv23_method");
 		return -1;
 	}
 
 	ctx = SSL_CTX_new(meth);
+	if (!ctx) {
+		ssl_socket_perror("SSL_CTX_new");
+		return -1;
+	}
+
+	if (use_tls_only)
+		SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3);
 
 	if (verify)
 		SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER, NULL);
@@ -862,7 +865,6 @@ static char hexchar(unsigned int b)
 static char *cram(const char *challenge_64, const char *user, const char *pass)
 {
 	int i, resp_len, encoded_len, decoded_len;
-	HMAC_CTX hmac;
 	unsigned char hash[16];
 	char hex[33];
 	char *response, *response_64, *challenge;
@@ -877,10 +879,8 @@ static char *cram(const char *challenge_64, const char *user, const char *pass)
 				      (unsigned char *)challenge_64, encoded_len);
 	if (decoded_len < 0)
 		die("invalid challenge %s", challenge_64);
-	HMAC_Init(&hmac, (unsigned char *)pass, strlen(pass), EVP_md5());
-	HMAC_Update(&hmac, (unsigned char *)challenge, decoded_len);
-	HMAC_Final(&hmac, hash, NULL);
-	HMAC_CTX_cleanup(&hmac);
+	if (!HMAC(EVP_md5(), pass, strlen(pass), (unsigned char *)challenge, decoded_len, hash, NULL))
+		die("HMAC error");
 
 	hex[32] = 0;
 	for (i = 0; i < 16; i++) {