openssl: replace openssl_hash() with openssl_digest()

The openssl_hash() function was used only by string_hashnum(); change it to use
openssl_digest() instead.

src/shared/openssl-util.c

@@ -50,43 +50,6 @@ int openssl_pkey_from_pem(const void *pem, size_t pem_size, EVP_PKEY **ret) {
         return 0;
 }
 
-int openssl_hash(const EVP_MD *alg,
-                 const void *msg,
-                 size_t msg_len,
-                 uint8_t *ret_hash,
-                 size_t *ret_hash_len) {
-
-        _cleanup_(EVP_MD_CTX_freep) EVP_MD_CTX *ctx = NULL;
-        unsigned len;
-        int r;
-
-        ctx = EVP_MD_CTX_new();
-        if (!ctx)
-                /* This function just calls OPENSSL_zalloc, so failure
-                 * here is almost certainly a failed allocation. */
-                return -ENOMEM;
-
-        /* The documentation claims EVP_DigestInit behaves just like
-         * EVP_DigestInit_ex if passed NULL, except it also calls
-         * EVP_MD_CTX_reset, which deinitializes the context. */
-        r = EVP_DigestInit_ex(ctx, alg, NULL);
-        if (r == 0)
-                return -EIO;
-
-        r = EVP_DigestUpdate(ctx, msg, msg_len);
-        if (r == 0)
-                return -EIO;
-
-        r = EVP_DigestFinal_ex(ctx, ret_hash, &len);
-        if (r == 0)
-                return -EIO;
-
-        if (ret_hash_len)
-                *ret_hash_len = len;
-
-        return 0;
-}
-
 /* Returns the number of bytes generated by the specified digest algorithm. This can be used only for
  * fixed-size algorithms, e.g. md5, sha1, sha256, etc. Do not use this for variable-sized digest algorithms,
  * e.g. shake128. Returns 0 on success, -EOPNOTSUPP if the algorithm is not supported, or < 0 for any other
@@ -681,18 +644,19 @@ int digest_and_sign(
 int string_hashsum(
                 const char *s,
                 size_t len,
-                const EVP_MD *md_algorithm,
+                const char *md_algorithm,
                 char **ret) {
 
-        uint8_t hash[EVP_MAX_MD_SIZE];
+        _cleanup_free_ void *hash = NULL;
         size_t hash_size;
-        char *enc;
+        _cleanup_free_ char *enc;
         int r;
 
-        hash_size = EVP_MD_size(md_algorithm);
-        assert(hash_size > 0);
+        assert(s || len == 0);
+        assert(md_algorithm);
+        assert(ret);
 
-        r = openssl_hash(md_algorithm, s, len, hash, NULL);
+        r = openssl_digest(md_algorithm, s, len, &hash, &hash_size);
         if (r < 0)
                 return r;
 
@@ -700,9 +664,8 @@ int string_hashsum(
         if (!enc)
                 return -ENOMEM;
 
-        *ret = enc;
+        *ret = TAKE_PTR(enc);
         return 0;
-
 }
 #  endif
 #endif

src/shared/openssl-util.h

@@ -57,8 +57,6 @@ static inline void sk_X509_free_allp(STACK_OF(X509) **sk) {
 
 int openssl_pkey_from_pem(const void *pem, size_t pem_size, EVP_PKEY **ret);
 
-int openssl_hash(const EVP_MD *alg, const void *msg, size_t msg_len, uint8_t *ret_hash, size_t *ret_hash_len);
-
 int openssl_digest_size(const char *digest_alg, size_t *ret_digest_size);
 
 int openssl_digest_many(const char *digest_alg, const struct iovec data[], size_t n_data, void **ret_digest, size_t *ret_digest_size);
@@ -130,13 +128,13 @@ typedef gcry_md_hd_t hash_context_t;
 #endif
 
 #if PREFER_OPENSSL
-int string_hashsum(const char *s, size_t len, hash_algorithm_t md_algorithm, char **ret);
+int string_hashsum(const char *s, size_t len, const char *md_algorithm, char **ret);
 
 static inline int string_hashsum_sha224(const char *s, size_t len, char **ret) {
-        return string_hashsum(s, len, EVP_sha224(), ret);
+        return string_hashsum(s, len, "SHA224", ret);
 }
 
 static inline int string_hashsum_sha256(const char *s, size_t len, char **ret) {
-        return string_hashsum(s, len, EVP_sha256(), ret);
+        return string_hashsum(s, len, "SHA256", ret);
 }
 #endif

src/test/test-cryptolib.c

@@ -11,25 +11,25 @@ TEST(string_hashsum) {
         _cleanup_free_ char *out1 = NULL, *out2 = NULL, *out3 = NULL, *out4 = NULL;
 
         assert_se(string_hashsum("asdf", 4,
-                                 OPENSSL_OR_GCRYPT(EVP_sha224(), GCRY_MD_SHA224),
+                                 OPENSSL_OR_GCRYPT("SHA224", GCRY_MD_SHA224),
                                  &out1) == 0);
         /* echo -n 'asdf' | sha224sum - */
         assert_se(streq(out1, "7872a74bcbf298a1e77d507cd95d4f8d96131cbbd4cdfc571e776c8a"));
 
         assert_se(string_hashsum("asdf", 4,
-                                 OPENSSL_OR_GCRYPT(EVP_sha256(), GCRY_MD_SHA256),
+                                 OPENSSL_OR_GCRYPT("SHA256", GCRY_MD_SHA256),
                                  &out2) == 0);
         /* echo -n 'asdf' | sha256sum - */
         assert_se(streq(out2, "f0e4c2f76c58916ec258f246851bea091d14d4247a2fc3e18694461b1816e13b"));
 
         assert_se(string_hashsum("", 0,
-                                 OPENSSL_OR_GCRYPT(EVP_sha224(), GCRY_MD_SHA224),
+                                 OPENSSL_OR_GCRYPT("SHA224", GCRY_MD_SHA224),
                                  &out3) == 0);
         /* echo -n '' | sha224sum - */
         assert_se(streq(out3, "d14a028c2a3a2bc9476102bb288234c415a2b01f828ea62ac5b3e42f"));
 
         assert_se(string_hashsum("", 0,
-                                 OPENSSL_OR_GCRYPT(EVP_sha256(), GCRY_MD_SHA256),
+                                 OPENSSL_OR_GCRYPT("SHA256", GCRY_MD_SHA256),
                                  &out4) == 0);
         /* echo -n '' | sha256sum - */
         assert_se(streq(out4, "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"));