[v3,09/12] crypto/hash-nettle: Implement new hash API

Commit Message

Alejandro Zeise Aug. 5, 2024, 3:50 p.m. UTC

Implements the new hashing API in the nettle hash driver.
Supports creating/destroying a context, updating the context
with input data and obtaining an output hash.

Signed-off-by: Alejandro Zeise <[e-mail]>
---
 crypto/hash-nettle.c | 81 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 81 insertions(+)

Patch

diff --git a/crypto/hash-nettle.c b/crypto/hash-nettle.c
index dbf1d96dfe..643f3d68b8 100644
--- a/crypto/hash-nettle.c
+++ b/crypto/hash-nettle.c
@@ -23,6 +23,7 @@ 
 #include "qapi/error.h"
 #include "crypto/hash.h"
 #include "hashpriv.h"
+#include <gnutls/crypto.h>
 #include <nettle/md5.h>
 #include <nettle/sha.h>
 #include <nettle/ripemd160.h>
@@ -105,7 +106,85 @@  gboolean qcrypto_hash_supports(QCryptoHashAlgorithm alg)
 }
 
 
+static
+QCryptoHash *qcrypto_nettle_hash_new(QCryptoHashAlgorithm alg, Error **errp)
+{
+    QCryptoHash *hash = NULL;
+
+    if (!qcrypto_hash_supports(alg)) {
+        error_setg(errp,
+                   "Unknown hash algorithm %d",
+                   alg);
+    } else {
+        hash = g_new(QCryptoHash, 1);
+        hash->alg = alg;
+        hash->opaque = g_new(union qcrypto_hash_ctx, 1);
+
+        qcrypto_hash_alg_map[alg].init(hash->opaque);
+    }
+
+    return hash;
+}
+
+static
+int qcrypto_nettle_hash_free(QCryptoHash *hash)
+{
+    union qcrypto_hash_ctx *ctx = hash->opaque;
+
+    g_free(ctx);
+    g_free(hash);
+
+    return 0;
+}
+
+static
+int qcrypto_nettle_hash_update(QCryptoHash *hash,
+                               const struct iovec *iov,
+                               size_t niov,
+                               Error **errp)
+{
+    union qcrypto_hash_ctx *ctx = hash->opaque;
+
+    for (int i = 0; i < niov; i++) {
+        /*
+         * Some versions of nettle have functions
+         * declared with 'int' instead of 'size_t'
+         * so to be safe avoid writing more than
+         * UINT_MAX bytes at a time
+         */
+        size_t len = iov[i].iov_len;
+        uint8_t *base = iov[i].iov_base;
+        while (len) {
+            size_t shortlen = MIN(len, UINT_MAX);
+            qcrypto_hash_alg_map[hash->alg].write(ctx, len, base);
+            len -= shortlen;
+            base += len;
+        }
+    }
+
+    return 0;
+}
+
+static
+int qcrypto_nettle_hash_finalize(QCryptoHash *hash,
+                                 uint8_t **result,
+                                 size_t *result_len,
+                                 Error **errp)
+{
+    union qcrypto_hash_ctx *ctx = hash->opaque;
+
+    *result_len = qcrypto_hash_alg_map[hash->alg].len;
+    *result = g_new(uint8_t, *result_len);
+
+    qcrypto_hash_alg_map[hash->alg].result(ctx, *result_len, *result);
+
+    return 0;
+}
 
 
 QCryptoHashDriver qcrypto_hash_lib_driver = {
+    .hash_new      = qcrypto_nettle_hash_new,
+    .hash_free     = qcrypto_nettle_hash_free,
+    .hash_update   = qcrypto_nettle_hash_update,
+    .hash_finalize = qcrypto_nettle_hash_finalize
 };