1 /* Blue Sky: File Systems in the Cloud
3 * Copyright (C) 2009 The Regents of the University of California
4 * Written by Michael Vrable <mvrable@cs.ucsd.edu>
18 /* Cryptographic operations. The rest of the BlueSky code merely calls into
19 * the functions in this file, so this is the only point where we interface
20 * with an external cryptographic library. */
22 GCRY_THREAD_OPTION_PTHREAD_IMPL;
24 void bluesky_crypt_init()
26 gcry_control(GCRYCTL_SET_THREAD_CBS, &gcry_threads_pthread);
28 if (gcry_control(GCRYCTL_INITIALIZATION_FINISHED_P))
31 g_print("libgcrypt not yet initialized, initializing...\n");
33 if (!gcry_check_version(GCRYPT_VERSION))
34 g_error("libgcrypt version mismatch\n");
36 gcry_control(GCRYCTL_DISABLE_SECMEM, 0);
37 gcry_control(GCRYCTL_INITIALIZATION_FINISHED, 0);
40 /* Return cryptographically-strong random data. */
41 void bluesky_crypt_random_bytes(guchar *buf, gint len)
43 gcry_randomize(buf, len, GCRY_STRONG_RANDOM);
46 /* Encrypt a data block. */
47 BlueSkyRCStr *bluesky_crypt_encrypt(BlueSkyRCStr *in, const uint8_t *key)
50 gcry_cipher_hd_t handle;
52 status = gcry_cipher_open(&handle, GCRY_CIPHER_AES, GCRY_CIPHER_MODE_CBC,
55 g_error("gcrypt error setting up encryption: %s\n",
56 gcry_strerror(status));
59 uint8_t *out = g_malloc0(in->len + CRYPTO_BLOCK_SIZE);
61 gcry_cipher_setkey(handle, key, CRYPTO_KEY_SIZE);
63 g_error("gcrypt error setting key: %s\n",
64 gcry_strerror(status));
67 bluesky_crypt_random_bytes(out, CRYPTO_BLOCK_SIZE);
68 status = gcry_cipher_setiv(handle, out, CRYPTO_BLOCK_SIZE);
70 g_error("gcrypt error setting IV: %s\n",
71 gcry_strerror(status));
74 status = gcry_cipher_encrypt(handle, out + CRYPTO_BLOCK_SIZE, in->len,
77 g_error("gcrypt error encrypting: %s\n",
78 gcry_strerror(status));
81 gcry_cipher_close(handle);
83 return bluesky_string_new(out, in->len + CRYPTO_BLOCK_SIZE);
86 /* Decrypt a data block. */
87 BlueSkyRCStr *bluesky_crypt_decrypt(BlueSkyRCStr *in, const uint8_t *key)
90 gcry_cipher_hd_t handle;
92 g_return_val_if_fail(in->len > CRYPTO_BLOCK_SIZE, NULL);
94 status = gcry_cipher_open(&handle, GCRY_CIPHER_AES, GCRY_CIPHER_MODE_CBC,
97 g_error("gcrypt error setting up encryption: %s\n",
98 gcry_strerror(status));
101 uint8_t *out = g_malloc0(in->len - CRYPTO_BLOCK_SIZE);
103 gcry_cipher_setkey(handle, key, CRYPTO_KEY_SIZE);
105 g_error("gcrypt error setting key: %s\n",
106 gcry_strerror(status));
109 status = gcry_cipher_setiv(handle, in->data, CRYPTO_BLOCK_SIZE);
111 g_error("gcrypt error setting IV: %s\n",
112 gcry_strerror(status));
115 status = gcry_cipher_decrypt(handle, out, in->len - CRYPTO_BLOCK_SIZE,
116 in->data + CRYPTO_BLOCK_SIZE,
117 in->len - CRYPTO_BLOCK_SIZE);
119 g_error("gcrypt error decrypting: %s\n",
120 gcry_strerror(status));
123 gcry_cipher_close(handle);
125 return bluesky_string_new(out, in->len + CRYPTO_BLOCK_SIZE);