Check return value for gcrypt functions

Author: paolostivanin

CMakeLists.txt

@@ -7,7 +7,7 @@ include(GNUInstallDirs)
 
 find_package(PkgConfig REQUIRED)
 find_package(Gcrypt 1.6.0 REQUIRED)
-pkg_check_modules(BASEENCODE REQUIRED baseencode>=1.0.5)
+pkg_check_modules(BASEENCODE REQUIRED baseencode>=1.0.14)
 
 include_directories(${GCRYPT_INCLUDE_DIR} ${BASEENCODE_INCLUDE_DIRS})
 
@@ -19,7 +19,7 @@ add_subdirectory(tests)
 # set up versioning.
 set(BUILD_MAJOR "1")
 set(BUILD_MINOR "2")
-set(BUILD_VERSION "6")
+set(BUILD_VERSION "7")
 set(BUILD_VERSION ${BUILD_MAJOR}.${BUILD_MINOR}.${BUILD_VERSION})
 
 set(CMAKE_C_STANDARD 11)

src/otp.c

@@ -106,7 +106,7 @@ static unsigned char *
 compute_hmac(const char *K, long C, int algo)
 {
     baseencode_error_t err;
-    size_t secret_len = (size_t) ((strlen(K) + 1.6 - 1) / 1.6);
+    size_t secret_len = (size_t)((strlen(K) + 1.6 - 1) / 1.6);
 
     char *normalized_K = normalize_secret (K);
     if (normalized_K == NULL) {
@@ -124,13 +124,24 @@ compute_hmac(const char *K, long C, int algo)
         C_reverse_byte_order[i] = ((unsigned char *) &C)[j];
 
     gcry_md_hd_t hd;
-    gcry_md_open(&hd, algo, GCRY_MD_FLAG_HMAC);
-    gcry_md_setkey(hd, secret, secret_len);
-    gcry_md_write(hd, C_reverse_byte_order, sizeof(C_reverse_byte_order));
+    gpg_error_t gpg_err = gcry_md_open (&hd, algo, GCRY_MD_FLAG_HMAC);
+    if (gpg_err) {
+        printf("%s\n", "Error while opening the cipher handle.");
+        return NULL;
+    }
+    gpg_err = gcry_md_setkey (hd, secret, secret_len);
+    if (gpg_err) {
+        printf("%s\n", "Error while setting the cipher key.");
+        gcry_md_close (hd);
+        return NULL;
+    }
+    gcry_md_write (hd, C_reverse_byte_order, sizeof(C_reverse_byte_order));
     gcry_md_final (hd);
-    unsigned char *hmac = gcry_md_read(hd, algo);
+    unsigned char *hmac = gcry_md_read (hd, algo);
+
+    free (secret);
 
-    free(secret);
+    gcry_md_close (hd);
 
     return hmac;
 }