crypto: add support for PBKDF2 algorithm

The LUKS data format includes use of PBKDF2 (Password-Based
Key Derivation Function). The Nettle library can provide
an implementation of this, but we don't want code directly
depending on a specific crypto library backend. Introduce
a new include/crypto/pbkdf.h header which defines a QEMU
API for invoking PBKDK2. The initial implementations are
backed by nettle & gcrypt, which are commonly available
with distros shipping GNUTLS.

The test suite data is taken from the cryptsetup codebase
under the LGPLv2.1+ license. This merely aims to verify
that whatever backend we provide for this function in QEMU
will comply with the spec.

Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

1 files changed, 392 insertions, 0 deletions

diff --git a/tests/test-crypto-pbkdf.c b/tests/test-crypto-pbkdf.c
new file mode 100644
index 0000000000..bb9c14c110
--- /dev/null
+++ b/tests/test-crypto-pbkdf.c
@@ -0,0 +1,392 @@
+/*
+ * QEMU Crypto cipher algorithms
+ *
+ * Copyright (c) 2015-2016 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "crypto/init.h"
+#ifndef _WIN32
+#include <sys/resource.h>
+#endif
+
+#if ((defined(CONFIG_NETTLE) || defined(CONFIG_GCRYPT)) && \
+     (defined(_WIN32) || defined(RUSAGE_THREAD)))
+#include "crypto/pbkdf.h"
+
+typedef struct QCryptoPbkdfTestData QCryptoPbkdfTestData;
+struct QCryptoPbkdfTestData {
+    const char *path;
+    QCryptoHashAlgorithm hash;
+    unsigned int iterations;
+    const char *key;
+    size_t nkey;
+    const char *salt;
+    size_t nsalt;
+    const char *out;
+    size_t nout;
+    bool slow;
+};
+
+/* This test data comes from cryptsetup package
+ *
+ *  $SRC/lib/crypto_backend/pbkdf2_generic.c
+ *
+ * under LGPLv2.1+ license
+ */
+static QCryptoPbkdfTestData test_data[] = {
+    /* RFC 3962 test data */
+    {
+        .path = "/crypto/pbkdf/rfc3962/sha1/iter1",
+        .hash = QCRYPTO_HASH_ALG_SHA1,
+        .iterations = 1,
+        .key = "password",
+        .nkey = 8,
+        .salt = "ATHENA.MIT.EDUraeburn",
+        .nsalt = 21,
+        .out = "\xcd\xed\xb5\x28\x1b\xb2\xf8\x01"
+               "\x56\x5a\x11\x22\xb2\x56\x35\x15"
+               "\x0a\xd1\xf7\xa0\x4b\xb9\xf3\xa3"
+               "\x33\xec\xc0\xe2\xe1\xf7\x08\x37",
+        .nout = 32
+    },
+    {
+        .path = "/crypto/pbkdf/rfc3962/sha1/iter2",
+        .hash = QCRYPTO_HASH_ALG_SHA1,
+        .iterations = 2,
+        .key = "password",
+        .nkey = 8,
+        .salt = "ATHENA.MIT.EDUraeburn",
+        .nsalt = 21,
+        .out = "\x01\xdb\xee\x7f\x4a\x9e\x24\x3e"
+               "\x98\x8b\x62\xc7\x3c\xda\x93\x5d"
+               "\xa0\x53\x78\xb9\x32\x44\xec\x8f"
+               "\x48\xa9\x9e\x61\xad\x79\x9d\x86",
+        .nout = 32
+    },
+    {
+        .path = "/crypto/pbkdf/rfc3962/sha1/iter1200a",
+        .hash = QCRYPTO_HASH_ALG_SHA1,
+        .iterations = 1200,
+        .key = "password",
+        .nkey = 8,
+        .salt = "ATHENA.MIT.EDUraeburn",
+        .nsalt = 21,
+        .out = "\x5c\x08\xeb\x61\xfd\xf7\x1e\x4e"
+               "\x4e\xc3\xcf\x6b\xa1\xf5\x51\x2b"
+               "\xa7\xe5\x2d\xdb\xc5\xe5\x14\x2f"
+               "\x70\x8a\x31\xe2\xe6\x2b\x1e\x13",
+        .nout = 32
+    },
+    {
+        .path = "/crypto/pbkdf/rfc3962/sha1/iter5",
+        .hash = QCRYPTO_HASH_ALG_SHA1,
+        .iterations = 5,
+        .key = "password",
+        .nkey = 8,
+        .salt = "\0224VxxV4\022", /* "\x1234567878563412 */
+        .nsalt = 8,
+        .out = "\xd1\xda\xa7\x86\x15\xf2\x87\xe6"
+               "\xa1\xc8\xb1\x20\xd7\x06\x2a\x49"
+               "\x3f\x98\xd2\x03\xe6\xbe\x49\xa6"
+               "\xad\xf4\xfa\x57\x4b\x6e\x64\xee",
+        .nout = 32
+    },
+    {
+        .path = "/crypto/pbkdf/rfc3962/sha1/iter1200b",
+        .hash = QCRYPTO_HASH_ALG_SHA1,
+        .iterations = 1200,
+        .key = "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
+               "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
+        .nkey = 64,
+        .salt = "pass phrase equals block size",
+        .nsalt = 29,
+        .out = "\x13\x9c\x30\xc0\x96\x6b\xc3\x2b"
+               "\xa5\x5f\xdb\xf2\x12\x53\x0a\xc9"
+               "\xc5\xec\x59\xf1\xa4\x52\xf5\xcc"
+               "\x9a\xd9\x40\xfe\xa0\x59\x8e\xd1",
+        .nout = 32
+    },
+    {
+        .path = "/crypto/pbkdf/rfc3962/sha1/iter1200c",
+        .hash = QCRYPTO_HASH_ALG_SHA1,
+        .iterations = 1200,
+        .key = "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
+               "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
+        .nkey = 65,
+        .salt = "pass phrase exceeds block size",
+        .nsalt = 30,
+        .out = "\x9c\xca\xd6\xd4\x68\x77\x0c\xd5"
+               "\x1b\x10\xe6\xa6\x87\x21\xbe\x61"
+               "\x1a\x8b\x4d\x28\x26\x01\xdb\x3b"
+               "\x36\xbe\x92\x46\x91\x5e\xc8\x2a",
+        .nout = 32
+    },
+    {
+        .path = "/crypto/pbkdf/rfc3962/sha1/iter50",
+        .hash = QCRYPTO_HASH_ALG_SHA1,
+        .iterations = 50,
+        .key = "\360\235\204\236", /* g-clef ("\xf09d849e) */
+        .nkey = 4,
+        .salt = "EXAMPLE.COMpianist",
+        .nsalt = 18,
+        .out = "\x6b\x9c\xf2\x6d\x45\x45\x5a\x43"
+               "\xa5\xb8\xbb\x27\x6a\x40\x3b\x39"
+               "\xe7\xfe\x37\xa0\xc4\x1e\x02\xc2"
+               "\x81\xff\x30\x69\xe1\xe9\x4f\x52",
+        .nout = 32
+    },
+
+    /* RFC-6070 test data */
+    {
+        .path = "/crypto/pbkdf/rfc6070/sha1/iter1",
+        .hash = QCRYPTO_HASH_ALG_SHA1,
+        .iterations = 1,
+        .key = "password",
+        .nkey = 8,
+        .salt = "salt",
+        .nsalt = 4,
+        .out = "\x0c\x60\xc8\x0f\x96\x1f\x0e\x71\xf3\xa9"
+               "\xb5\x24\xaf\x60\x12\x06\x2f\xe0\x37\xa6",
+        .nout = 20
+    },
+    {
+        .path = "/crypto/pbkdf/rfc6070/sha1/iter2",
+        .hash = QCRYPTO_HASH_ALG_SHA1,
+        .iterations = 2,
+        .key = "password",
+        .nkey = 8,
+        .salt = "salt",
+        .nsalt = 4,
+        .out = "\xea\x6c\x01\x4d\xc7\x2d\x6f\x8c\xcd\x1e"
+               "\xd9\x2a\xce\x1d\x41\xf0\xd8\xde\x89\x57",
+        .nout = 20
+    },
+    {
+        .path = "/crypto/pbkdf/rfc6070/sha1/iter4096",
+        .hash = QCRYPTO_HASH_ALG_SHA1,
+        .iterations = 4096,
+        .key = "password",
+        .nkey = 8,
+        .salt = "salt",
+        .nsalt = 4,
+        .out = "\x4b\x00\x79\x01\xb7\x65\x48\x9a\xbe\xad"
+               "\x49\xd9\x26\xf7\x21\xd0\x65\xa4\x29\xc1",
+        .nout = 20
+    },
+    {
+        .path = "/crypto/pbkdf/rfc6070/sha1/iter16777216",
+        .hash = QCRYPTO_HASH_ALG_SHA1,
+        .iterations = 16777216,
+        .key = "password",
+        .nkey = 8,
+        .salt = "salt",
+        .nsalt = 4,
+        .out = "\xee\xfe\x3d\x61\xcd\x4d\xa4\xe4\xe9\x94"
+               "\x5b\x3d\x6b\xa2\x15\x8c\x26\x34\xe9\x84",
+        .nout = 20,
+        .slow = true,
+    },
+    {
+        .path = "/crypto/pbkdf/rfc6070/sha1/iter4096a",
+        .hash = QCRYPTO_HASH_ALG_SHA1,
+        .iterations = 4096,
+        .key = "passwordPASSWORDpassword",
+        .nkey = 24,
+        .salt = "saltSALTsaltSALTsaltSALTsaltSALTsalt",
+        .nsalt = 36,
+        .out = "\x3d\x2e\xec\x4f\xe4\x1c\x84\x9b\x80\xc8"
+               "\xd8\x36\x62\xc0\xe4\x4a\x8b\x29\x1a\x96"
+               "\x4c\xf2\xf0\x70\x38",
+        .nout = 25
+    },
+    {
+        .path = "/crypto/pbkdf/rfc6070/sha1/iter4096b",
+        .hash = QCRYPTO_HASH_ALG_SHA1,
+        .iterations = 4096,
+        .key = "pass\0word",
+        .nkey = 9,
+        .salt = "sa\0lt",
+        .nsalt = 5,
+        .out = "\x56\xfa\x6a\xa7\x55\x48\x09\x9d\xcc\x37"
+               "\xd7\xf0\x34\x25\xe0\xc3",
+        .nout = 16
+    },
+
+    /* non-RFC misc test data */
+#ifdef CONFIG_NETTLE
+    {
+        /* empty password test.
+         * Broken with libgcrypt <= 1.5.0, hence CONFIG_NETTLE */
+        .path = "/crypto/pbkdf/nonrfc/sha1/iter2",
+        .hash = QCRYPTO_HASH_ALG_SHA1,
+        .iterations = 2,
+        .key = "",
+        .nkey = 0,
+        .salt = "salt",
+        .nsalt = 4,
+        .out = "\x13\x3a\x4c\xe8\x37\xb4\xd2\x52\x1e\xe2"
+               "\xbf\x03\xe1\x1c\x71\xca\x79\x4e\x07\x97",
+        .nout = 20
+    },
+#endif
+    {
+        /* Password exceeds block size test */
+        .path = "/crypto/pbkdf/nonrfc/sha256/iter1200",
+        .hash = QCRYPTO_HASH_ALG_SHA256,
+        .iterations = 1200,
+        .key = "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
+               "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
+        .nkey = 65,
+        .salt = "pass phrase exceeds block size",
+        .nsalt = 30,
+        .out = "\x22\x34\x4b\xc4\xb6\xe3\x26\x75"
+               "\xa8\x09\x0f\x3e\xa8\x0b\xe0\x1d"
+               "\x5f\x95\x12\x6a\x2c\xdd\xc3\xfa"
+               "\xcc\x4a\x5e\x6d\xca\x04\xec\x58",
+        .nout = 32
+    },
+#if 0
+    {
+        .path = "/crypto/pbkdf/nonrfc/sha512/iter1200",
+        .hash = QCRYPTO_HASH_ALG_SHA512,
+        .iterations = 1200,
+        .key = "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
+               "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
+               "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
+               "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
+        .nkey = 129,
+        .salt = "pass phrase exceeds block size",
+        .nsalt = 30,
+        .out = "\x0f\xb2\xed\x2c\x0e\x6e\xfb\x7d"
+               "\x7d\x8e\xdd\x58\x01\xb4\x59\x72"
+               "\x99\x92\x16\x30\x5e\xa4\x36\x8d"
+               "\x76\x14\x80\xf3\xe3\x7a\x22\xb9",
+        .nout = 32
+    },
+    {
+        .path = "/crypto/pbkdf/nonrfc/whirlpool/iter1200",
+        .hash = QCRYPTO_HASH_ALG_WHIRLPOOL,
+        .iterations = 1200,
+        .key = "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
+               "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
+        .nkey = 65,
+        .salt = "pass phrase exceeds block size",
+        .nsalt = 30,
+        .out = "\x9c\x1c\x74\xf5\x88\x26\xe7\x6a"
+               "\x53\x58\xf4\x0c\x39\xe7\x80\x89"
+               "\x07\xc0\x31\x19\x9a\x50\xa2\x48"
+               "\xf1\xd9\xfe\x78\x64\xe5\x84\x50",
+        .nout = 32
+    }
+#endif
+};
+
+
+static inline char hex(int i)
+{
+    if (i < 10) {
+        return '0' + i;
+    }
+    return 'a' + (i - 10);
+}
+
+static char *hex_string(const uint8_t *bytes,
+                        size_t len)
+{
+    char *hexstr = g_new0(char, len * 2 + 1);
+    size_t i;
+
+    for (i = 0; i < len; i++) {
+        hexstr[i * 2] = hex((bytes[i] >> 4) & 0xf);
+        hexstr[i * 2 + 1] = hex(bytes[i] & 0xf);
+    }
+    hexstr[len * 2] = '\0';
+
+    return hexstr;
+}
+
+static void test_pbkdf(const void *opaque)
+{
+    const QCryptoPbkdfTestData *data = opaque;
+    size_t nout = data->nout;
+    uint8_t *out = g_new0(uint8_t, nout);
+    gchar *expect, *actual;
+
+    qcrypto_pbkdf2(data->hash,
+                   (uint8_t *)data->key, data->nkey,
+                   (uint8_t *)data->salt, data->nsalt,
+                   data->iterations,
+                   (uint8_t *)out, nout,
+                   &error_abort);
+
+    expect = hex_string((const uint8_t *)data->out, data->nout);
+    actual = hex_string(out, nout);
+
+    g_assert_cmpstr(actual, ==, expect);
+
+    g_free(actual);
+    g_free(expect);
+    g_free(out);
+}
+
+
+static void test_pbkdf_timing(void)
+{
+    uint8_t key[32];
+    uint8_t salt[32];
+    int iters;
+
+    memset(key, 0x5d, sizeof(key));
+    memset(salt, 0x7c, sizeof(salt));
+
+    iters = qcrypto_pbkdf2_count_iters(QCRYPTO_HASH_ALG_SHA256,
+                                       key, sizeof(key),
+                                       salt, sizeof(salt),
+                                       &error_abort);
+
+    g_assert(iters >= (1 << 15));
+}
+
+
+int main(int argc, char **argv)
+{
+    size_t i;
+
+    g_test_init(&argc, &argv, NULL);
+
+    g_assert(qcrypto_init(NULL) == 0);
+
+    for (i = 0; i < G_N_ELEMENTS(test_data); i++) {
+        if (!test_data[i].slow ||
+            g_test_slow()) {
+            g_test_add_data_func(test_data[i].path, &test_data[i], test_pbkdf);
+        }
+    }
+
+    if (g_test_slow()) {
+        g_test_add_func("/crypt0/pbkdf/timing", test_pbkdf_timing);
+    }
+
+    return g_test_run();
+}
+#else
+int main(int argc, char **argv)
+{
+    return 0;
+}
+#endif