diff options
Diffstat (limited to 'block/qcow.c')
-rw-r--r-- | block/qcow.c | 198 |
1 files changed, 96 insertions, 102 deletions
diff --git a/block/qcow.c b/block/qcow.c index 3a3dbf9439..db0c5a9016 100644 --- a/block/qcow.c +++ b/block/qcow.c @@ -31,8 +31,10 @@ #include "qemu/bswap.h" #include <zlib.h> #include "qapi/qmp/qerror.h" -#include "crypto/cipher.h" +#include "qapi/qmp/qstring.h" +#include "crypto/block.h" #include "migration/blocker.h" +#include "block/crypto.h" /**************************************************************/ /* QEMU COW block driver with compression and encryption support */ @@ -77,7 +79,7 @@ typedef struct BDRVQcowState { uint8_t *cluster_cache; uint8_t *cluster_data; uint64_t cluster_cache_offset; - QCryptoCipher *cipher; /* NULL if no key yet */ + QCryptoBlock *crypto; /* Disk encryption format driver */ uint32_t crypt_method_header; CoMutex lock; Error *migration_blocker; @@ -97,6 +99,15 @@ static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename) return 0; } +static QemuOptsList qcow_runtime_opts = { + .name = "qcow", + .head = QTAILQ_HEAD_INITIALIZER(qcow_runtime_opts.head), + .desc = { + BLOCK_CRYPTO_OPT_DEF_QCOW_KEY_SECRET("encrypt."), + { /* end of list */ } + }, +}; + static int qcow_open(BlockDriverState *bs, QDict *options, int flags, Error **errp) { @@ -105,11 +116,19 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags, int ret; QCowHeader header; Error *local_err = NULL; + QCryptoBlockOpenOptions *crypto_opts = NULL; + unsigned int cflags = 0; + QDict *encryptopts = NULL; + const char *encryptfmt; + + qdict_extract_subqdict(options, &encryptopts, "encrypt."); + encryptfmt = qdict_get_try_str(encryptopts, "format"); bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file, false, errp); if (!bs->file) { - return -EINVAL; + ret = -EINVAL; + goto fail; } ret = bdrv_pread(bs->file, 0, &header, sizeof(header)); @@ -155,17 +174,6 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags, goto fail; } - if (header.crypt_method > QCOW_CRYPT_AES) { - error_setg(errp, "invalid encryption method in qcow header"); - ret = -EINVAL; - goto fail; - } - if (!qcrypto_cipher_supports(QCRYPTO_CIPHER_ALG_AES_128, - QCRYPTO_CIPHER_MODE_CBC)) { - error_setg(errp, "AES cipher not available"); - ret = -EINVAL; - goto fail; - } s->crypt_method_header = header.crypt_method; if (s->crypt_method_header) { if (bdrv_uses_whitelist() && @@ -181,8 +189,38 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags, ret = -ENOSYS; goto fail; } + if (s->crypt_method_header == QCOW_CRYPT_AES) { + if (encryptfmt && !g_str_equal(encryptfmt, "aes")) { + error_setg(errp, + "Header reported 'aes' encryption format but " + "options specify '%s'", encryptfmt); + ret = -EINVAL; + goto fail; + } + qdict_del(encryptopts, "format"); + crypto_opts = block_crypto_open_opts_init( + Q_CRYPTO_BLOCK_FORMAT_QCOW, encryptopts, errp); + if (!crypto_opts) { + ret = -EINVAL; + goto fail; + } + if (flags & BDRV_O_NO_IO) { + cflags |= QCRYPTO_BLOCK_OPEN_NO_IO; + } + s->crypto = qcrypto_block_open(crypto_opts, NULL, NULL, + cflags, errp); + if (!s->crypto) { + ret = -EINVAL; + goto fail; + } + } else { + error_setg(errp, "invalid encryption method in qcow header"); + ret = -EINVAL; + goto fail; + } bs->encrypted = true; + bs->valid_key = true; } s->cluster_bits = header.cluster_bits; s->cluster_size = 1 << s->cluster_bits; @@ -266,6 +304,8 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags, goto fail; } + QDECREF(encryptopts); + qapi_free_QCryptoBlockOpenOptions(crypto_opts); qemu_co_mutex_init(&s->lock); return 0; @@ -274,6 +314,9 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags, qemu_vfree(s->l2_cache); g_free(s->cluster_cache); g_free(s->cluster_data); + qcrypto_block_free(s->crypto); + QDECREF(encryptopts); + qapi_free_QCryptoBlockOpenOptions(crypto_opts); return ret; } @@ -286,81 +329,6 @@ static int qcow_reopen_prepare(BDRVReopenState *state, return 0; } -static int qcow_set_key(BlockDriverState *bs, const char *key) -{ - BDRVQcowState *s = bs->opaque; - uint8_t keybuf[16]; - int len, i; - Error *err; - - memset(keybuf, 0, 16); - len = strlen(key); - if (len > 16) - len = 16; - /* XXX: we could compress the chars to 7 bits to increase - entropy */ - for(i = 0;i < len;i++) { - keybuf[i] = key[i]; - } - assert(bs->encrypted); - - qcrypto_cipher_free(s->cipher); - s->cipher = qcrypto_cipher_new( - QCRYPTO_CIPHER_ALG_AES_128, - QCRYPTO_CIPHER_MODE_CBC, - keybuf, G_N_ELEMENTS(keybuf), - &err); - - if (!s->cipher) { - /* XXX would be nice if errors in this method could - * be properly propagate to the caller. Would need - * the bdrv_set_key() API signature to be fixed. */ - error_free(err); - return -1; - } - return 0; -} - -/* The crypt function is compatible with the linux cryptoloop - algorithm for < 4 GB images. */ -static int encrypt_sectors(BDRVQcowState *s, int64_t sector_num, - uint8_t *buf, int nb_sectors, bool enc, - Error **errp) -{ - union { - uint64_t ll[2]; - uint8_t b[16]; - } ivec; - int i; - int ret; - - for(i = 0; i < nb_sectors; i++) { - ivec.ll[0] = cpu_to_le64(sector_num); - ivec.ll[1] = 0; - if (qcrypto_cipher_setiv(s->cipher, - ivec.b, G_N_ELEMENTS(ivec.b), - errp) < 0) { - return -1; - } - if (enc) { - ret = qcrypto_cipher_encrypt(s->cipher, - buf, buf, - 512, - errp); - } else { - ret = qcrypto_cipher_decrypt(s->cipher, - buf, buf, - 512, - errp); - } - if (ret < 0) { - return -1; - } - sector_num++; - buf += 512; - } - return 0; -} /* 'allocate' is: * @@ -475,15 +443,16 @@ static uint64_t get_cluster_offset(BlockDriverState *bs, if (bs->encrypted && (n_end - n_start) < s->cluster_sectors) { uint64_t start_sect; - assert(s->cipher); + assert(s->crypto); start_sect = (offset & ~(s->cluster_size - 1)) >> 9; for(i = 0; i < s->cluster_sectors; i++) { if (i < n_start || i >= n_end) { Error *err = NULL; memset(s->cluster_data, 0x00, 512); - if (encrypt_sectors(s, start_sect + i, - s->cluster_data, 1, - true, &err) < 0) { + if (qcrypto_block_encrypt(s->crypto, start_sect + i, + s->cluster_data, + BDRV_SECTOR_SIZE, + &err) < 0) { error_free(err); errno = EIO; return -1; @@ -528,7 +497,7 @@ static int64_t coroutine_fn qcow_co_get_block_status(BlockDriverState *bs, if (!cluster_offset) { return 0; } - if ((cluster_offset & QCOW_OFLAG_COMPRESSED) || s->cipher) { + if ((cluster_offset & QCOW_OFLAG_COMPRESSED) || s->crypto) { return BDRV_BLOCK_DATA; } cluster_offset |= (index_in_cluster << BDRV_SECTOR_BITS); @@ -659,9 +628,9 @@ static coroutine_fn int qcow_co_readv(BlockDriverState *bs, int64_t sector_num, break; } if (bs->encrypted) { - assert(s->cipher); - if (encrypt_sectors(s, sector_num, buf, - n, false, &err) < 0) { + assert(s->crypto); + if (qcrypto_block_decrypt(s->crypto, sector_num, buf, + n * BDRV_SECTOR_SIZE, &err) < 0) { goto fail; } } @@ -734,8 +703,9 @@ static coroutine_fn int qcow_co_writev(BlockDriverState *bs, int64_t sector_num, } if (bs->encrypted) { Error *err = NULL; - assert(s->cipher); - if (encrypt_sectors(s, sector_num, buf, n, true, &err) < 0) { + assert(s->crypto); + if (qcrypto_block_encrypt(s->crypto, sector_num, buf, + n * BDRV_SECTOR_SIZE, &err) < 0) { error_free(err); ret = -EIO; break; @@ -770,8 +740,8 @@ static void qcow_close(BlockDriverState *bs) { BDRVQcowState *s = bs->opaque; - qcrypto_cipher_free(s->cipher); - s->cipher = NULL; + qcrypto_block_free(s->crypto); + s->crypto = NULL; g_free(s->l1_table); qemu_vfree(s->l2_cache); g_free(s->cluster_cache); @@ -792,6 +762,10 @@ static int qcow_create(const char *filename, QemuOpts *opts, Error **errp) int ret; BlockBackend *qcow_blk; const char *encryptfmt = NULL; + QDict *options; + QDict *encryptopts = NULL; + QCryptoBlockCreateOptions *crypto_opts = NULL; + QCryptoBlock *crypto = NULL; /* Read out options */ total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0), @@ -866,6 +840,10 @@ static int qcow_create(const char *filename, QemuOpts *opts, Error **errp) l1_size = (total_size + (1LL << shift) - 1) >> shift; header.l1_table_offset = cpu_to_be64(header_size); + + options = qemu_opts_to_qdict(opts, NULL); + qdict_extract_subqdict(options, &encryptopts, "encrypt."); + QDECREF(options); if (encryptfmt) { if (!g_str_equal(encryptfmt, "aes")) { error_setg(errp, "Unknown encryption format '%s', expected 'aes'", @@ -874,6 +852,19 @@ static int qcow_create(const char *filename, QemuOpts *opts, Error **errp) goto exit; } header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES); + + crypto_opts = block_crypto_create_opts_init( + Q_CRYPTO_BLOCK_FORMAT_QCOW, encryptopts, errp); + if (!crypto_opts) { + ret = -EINVAL; + goto exit; + } + + crypto = qcrypto_block_create(crypto_opts, NULL, NULL, NULL, errp); + if (!crypto) { + ret = -EINVAL; + goto exit; + } } else { header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE); } @@ -908,6 +899,9 @@ static int qcow_create(const char *filename, QemuOpts *opts, Error **errp) exit: blk_unref(qcow_blk); cleanup: + QDECREF(encryptopts); + qcrypto_block_free(crypto); + qapi_free_QCryptoBlockCreateOptions(crypto_opts); g_free(backing_file); return ret; } @@ -1054,6 +1048,7 @@ static QemuOptsList qcow_create_opts = { .type = QEMU_OPT_STRING, .help = "Encrypt the image, format choices: 'aes'", }, + BLOCK_CRYPTO_OPT_DEF_QCOW_KEY_SECRET("encrypt."), { /* end of list */ } } }; @@ -1074,7 +1069,6 @@ static BlockDriver bdrv_qcow = { .bdrv_co_writev = qcow_co_writev, .bdrv_co_get_block_status = qcow_co_get_block_status, - .bdrv_set_key = qcow_set_key, .bdrv_make_empty = qcow_make_empty, .bdrv_co_pwritev_compressed = qcow_co_pwritev_compressed, .bdrv_get_info = qcow_get_info, |