]> git.proxmox.com Git - mirror_qemu.git/blobdiff - crypto/block-luks.c
crypto/block: rename qcrypto_block_*crypt_helper
[mirror_qemu.git] / crypto / block-luks.c
index aba4455646fb6a46d30c11a26dacc02f0fee0135..353a400595d1417607886713de5a820da6b204e3 100644 (file)
 #include "qapi/error.h"
 #include "qemu/bswap.h"
 
-#include "crypto/block-luks.h"
+#include "block-luks.h"
 
 #include "crypto/hash.h"
 #include "crypto/afsplit.h"
 #include "crypto/pbkdf.h"
 #include "crypto/secret.h"
 #include "crypto/random.h"
-
-#ifdef CONFIG_UUID
-#include <uuid/uuid.h>
-#endif
+#include "qemu/uuid.h"
 
 #include "qemu/coroutine.h"
 
@@ -260,47 +257,41 @@ qcrypto_block_luks_cipher_alg_lookup(QCryptoCipherAlgorithm alg,
     }
 
     error_setg(errp, "Algorithm '%s' not supported",
-               QCryptoCipherAlgorithm_lookup[alg]);
+               QCryptoCipherAlgorithm_str(alg));
     return NULL;
 }
 
 /* XXX replace with qapi_enum_parse() in future, when we can
  * make that function emit a more friendly error message */
 static int qcrypto_block_luks_name_lookup(const char *name,
-                                          const char *const *map,
-                                          size_t maplen,
+                                          const QEnumLookup *map,
                                           const char *type,
                                           Error **errp)
 {
-    size_t i;
-    for (i = 0; i < maplen; i++) {
-        if (g_str_equal(map[i], name)) {
-            return i;
-        }
-    }
+    int ret = qapi_enum_parse(map, name, -1, NULL);
 
-    error_setg(errp, "%s %s not supported", type, name);
-    return 0;
+    if (ret < 0) {
+        error_setg(errp, "%s %s not supported", type, name);
+        return 0;
+    }
+    return ret;
 }
 
 #define qcrypto_block_luks_cipher_mode_lookup(name, errp)               \
     qcrypto_block_luks_name_lookup(name,                                \
-                                   QCryptoCipherMode_lookup,            \
-                                   QCRYPTO_CIPHER_MODE__MAX,            \
+                                   &QCryptoCipherMode_lookup,           \
                                    "Cipher mode",                       \
                                    errp)
 
 #define qcrypto_block_luks_hash_name_lookup(name, errp)                 \
     qcrypto_block_luks_name_lookup(name,                                \
-                                   QCryptoHashAlgorithm_lookup,         \
-                                   QCRYPTO_HASH_ALG__MAX,               \
+                                   &QCryptoHashAlgorithm_lookup,        \
                                    "Hash algorithm",                    \
                                    errp)
 
 #define qcrypto_block_luks_ivgen_name_lookup(name, errp)                \
     qcrypto_block_luks_name_lookup(name,                                \
-                                   QCryptoIVGenAlgorithm_lookup,        \
-                                   QCRYPTO_IVGEN_ALG__MAX,              \
+                                   &QCryptoIVGenAlgorithm_lookup,       \
                                    "IV generator",                      \
                                    errp)
 
@@ -401,7 +392,7 @@ qcrypto_block_luks_essiv_cipher(QCryptoCipherAlgorithm cipher,
         break;
     default:
         error_setg(errp, "Cipher %s not supported with essiv",
-                   QCryptoCipherAlgorithm_lookup[cipher]);
+                   QCryptoCipherAlgorithm_str(cipher));
         return 0;
     }
 }
@@ -478,8 +469,8 @@ qcrypto_block_luks_load_key(QCryptoBlock *block,
     rv = readfunc(block,
                   slot->key_offset * QCRYPTO_BLOCK_LUKS_SECTOR_SIZE,
                   splitkey, splitkeylen,
-                  errp,
-                  opaque);
+                  opaque,
+                  errp);
     if (rv < 0) {
         goto cleanup;
     }
@@ -513,14 +504,14 @@ qcrypto_block_luks_load_key(QCryptoBlock *block,
      * to reset the encryption cipher every time the master
      * key crosses a sector boundary.
      */
-    if (qcrypto_block_decrypt_helper(cipher,
-                                     niv,
-                                     ivgen,
-                                     QCRYPTO_BLOCK_LUKS_SECTOR_SIZE,
-                                     0,
-                                     splitkey,
-                                     splitkeylen,
-                                     errp) < 0) {
+    if (qcrypto_block_cipher_decrypt_helper(cipher,
+                                            niv,
+                                            ivgen,
+                                            QCRYPTO_BLOCK_LUKS_SECTOR_SIZE,
+                                            0,
+                                            splitkey,
+                                            splitkeylen,
+                                            errp) < 0) {
         goto cleanup;
     }
 
@@ -641,6 +632,7 @@ qcrypto_block_luks_find_key(QCryptoBlock *block,
 static int
 qcrypto_block_luks_open(QCryptoBlock *block,
                         QCryptoBlockOpenOptions *options,
+                        const char *optprefix,
                         QCryptoBlockReadFunc readfunc,
                         void *opaque,
                         unsigned int flags,
@@ -664,7 +656,8 @@ qcrypto_block_luks_open(QCryptoBlock *block,
 
     if (!(flags & QCRYPTO_BLOCK_OPEN_NO_IO)) {
         if (!options->u.luks.key_secret) {
-            error_setg(errp, "Parameter 'key-secret' is required for cipher");
+            error_setg(errp, "Parameter '%skey-secret' is required for cipher",
+                       optprefix ? optprefix : "");
             return -1;
         }
         password = qcrypto_secret_lookup_as_utf8(
@@ -682,8 +675,8 @@ qcrypto_block_luks_open(QCryptoBlock *block,
     rv = readfunc(block, 0,
                   (uint8_t *)&luks->header,
                   sizeof(luks->header),
-                  errp,
-                  opaque);
+                  opaque,
+                  errp);
     if (rv < 0) {
         ret = rv;
         goto fail;
@@ -853,8 +846,9 @@ qcrypto_block_luks_open(QCryptoBlock *block,
         }
     }
 
+    block->sector_size = QCRYPTO_BLOCK_LUKS_SECTOR_SIZE;
     block->payload_offset = luks->header.payload_offset *
-        QCRYPTO_BLOCK_LUKS_SECTOR_SIZE;
+        block->sector_size;
 
     luks->cipher_alg = cipheralg;
     luks->cipher_mode = ciphermode;
@@ -877,23 +871,18 @@ qcrypto_block_luks_open(QCryptoBlock *block,
 }
 
 
-static int
-qcrypto_block_luks_uuid_gen(uint8_t *uuidstr, Error **errp)
+static void
+qcrypto_block_luks_uuid_gen(uint8_t *uuidstr)
 {
-#ifdef CONFIG_UUID
-    uuid_t uuid;
-    uuid_generate(uuid);
-    uuid_unparse(uuid, (char *)uuidstr);
-    return 0;
-#else
-    error_setg(errp, "Unable to generate uuids on this platform");
-    return -1;
-#endif
+    QemuUUID uuid;
+    qemu_uuid_generate(&uuid);
+    qemu_uuid_unparse(&uuid, (char *)uuidstr);
 }
 
 static int
 qcrypto_block_luks_create(QCryptoBlock *block,
                           QCryptoBlockCreateOptions *options,
+                          const char *optprefix,
                           QCryptoBlockInitFunc initfunc,
                           QCryptoBlockWriteFunc writefunc,
                           void *opaque,
@@ -917,8 +906,12 @@ qcrypto_block_luks_create(QCryptoBlock *block,
     const char *hash_alg;
     char *cipher_mode_spec = NULL;
     QCryptoCipherAlgorithm ivcipheralg = 0;
+    uint64_t iters;
 
     memcpy(&luks_opts, &options->u.luks, sizeof(luks_opts));
+    if (!luks_opts.has_iter_time) {
+        luks_opts.iter_time = 2000;
+    }
     if (!luks_opts.has_cipher_alg) {
         luks_opts.cipher_alg = QCRYPTO_CIPHER_ALG_AES_256;
     }
@@ -942,7 +935,8 @@ qcrypto_block_luks_create(QCryptoBlock *block,
      * be silently ignored, for compatibility with dm-crypt */
 
     if (!options->u.luks.key_secret) {
-        error_setg(errp, "Parameter 'key-secret' is required for cipher");
+        error_setg(errp, "Parameter '%skey-secret' is required for cipher",
+                   optprefix ? optprefix : "");
         return -1;
     }
     password = qcrypto_secret_lookup_as_utf8(luks_opts.key_secret, errp);
@@ -961,10 +955,7 @@ qcrypto_block_luks_create(QCryptoBlock *block,
      * it out to disk
      */
     luks->header.version = QCRYPTO_BLOCK_LUKS_VERSION;
-    if (qcrypto_block_luks_uuid_gen(luks->header.uuid,
-                                    errp) < 0) {
-        goto error;
-    }
+    qcrypto_block_luks_uuid_gen(luks->header.uuid);
 
     cipher_alg = qcrypto_block_luks_cipher_alg_lookup(luks_opts.cipher_alg,
                                                       errp);
@@ -972,16 +963,16 @@ qcrypto_block_luks_create(QCryptoBlock *block,
         goto error;
     }
 
-    cipher_mode = QCryptoCipherMode_lookup[luks_opts.cipher_mode];
-    ivgen_alg = QCryptoIVGenAlgorithm_lookup[luks_opts.ivgen_alg];
+    cipher_mode = QCryptoCipherMode_str(luks_opts.cipher_mode);
+    ivgen_alg = QCryptoIVGenAlgorithm_str(luks_opts.ivgen_alg);
     if (luks_opts.has_ivgen_hash_alg) {
-        ivgen_hash_alg = QCryptoHashAlgorithm_lookup[luks_opts.ivgen_hash_alg];
+        ivgen_hash_alg = QCryptoHashAlgorithm_str(luks_opts.ivgen_hash_alg);
         cipher_mode_spec = g_strdup_printf("%s-%s:%s", cipher_mode, ivgen_alg,
                                            ivgen_hash_alg);
     } else {
         cipher_mode_spec = g_strdup_printf("%s-%s", cipher_mode, ivgen_alg);
     }
-    hash_alg = QCryptoHashAlgorithm_lookup[luks_opts.hash_alg];
+    hash_alg = QCryptoHashAlgorithm_str(luks_opts.hash_alg);
 
 
     if (strlen(cipher_alg) >= QCRYPTO_BLOCK_LUKS_CIPHER_NAME_LEN) {
@@ -1064,26 +1055,40 @@ qcrypto_block_luks_create(QCryptoBlock *block,
     /* Determine how many iterations we need to hash the master
      * key, in order to have 1 second of compute time used
      */
-    luks->header.master_key_iterations =
-        qcrypto_pbkdf2_count_iters(luks_opts.hash_alg,
-                                   masterkey, luks->header.key_bytes,
-                                   luks->header.master_key_salt,
-                                   QCRYPTO_BLOCK_LUKS_SALT_LEN,
-                                   &local_err);
+    iters = qcrypto_pbkdf2_count_iters(luks_opts.hash_alg,
+                                       masterkey, luks->header.key_bytes,
+                                       luks->header.master_key_salt,
+                                       QCRYPTO_BLOCK_LUKS_SALT_LEN,
+                                       QCRYPTO_BLOCK_LUKS_DIGEST_LEN,
+                                       &local_err);
     if (local_err) {
         error_propagate(errp, local_err);
         goto error;
     }
 
+    if (iters > (ULLONG_MAX / luks_opts.iter_time)) {
+        error_setg_errno(errp, ERANGE,
+                         "PBKDF iterations %llu too large to scale",
+                         (unsigned long long)iters);
+        goto error;
+    }
+
+    /* iter_time was in millis, but count_iters reported for secs */
+    iters = iters * luks_opts.iter_time / 1000;
+
     /* Why /= 8 ?  That matches cryptsetup, but there's no
      * explanation why they chose /= 8... Probably so that
      * if all 8 keyslots are active we only spend 1 second
      * in total time to check all keys */
-    luks->header.master_key_iterations /= 8;
-    luks->header.master_key_iterations = MAX(
-        luks->header.master_key_iterations,
-        QCRYPTO_BLOCK_LUKS_MIN_MASTER_KEY_ITERS);
-
+    iters /= 8;
+    if (iters > UINT32_MAX) {
+        error_setg_errno(errp, ERANGE,
+                         "PBKDF iterations %llu larger than %u",
+                         (unsigned long long)iters, UINT32_MAX);
+        goto error;
+    }
+    iters = MAX(iters, QCRYPTO_BLOCK_LUKS_MIN_MASTER_KEY_ITERS);
+    luks->header.master_key_iterations = iters;
 
     /* Hash the master key, saving the result in the LUKS
      * header. This hash is used when opening the encrypted
@@ -1131,22 +1136,36 @@ qcrypto_block_luks_create(QCryptoBlock *block,
     /* Again we determine how many iterations are required to
      * hash the user password while consuming 1 second of compute
      * time */
-    luks->header.key_slots[0].iterations =
-        qcrypto_pbkdf2_count_iters(luks_opts.hash_alg,
-                                   (uint8_t *)password, strlen(password),
-                                   luks->header.key_slots[0].salt,
-                                   QCRYPTO_BLOCK_LUKS_SALT_LEN,
-                                   &local_err);
+    iters = qcrypto_pbkdf2_count_iters(luks_opts.hash_alg,
+                                       (uint8_t *)password, strlen(password),
+                                       luks->header.key_slots[0].salt,
+                                       QCRYPTO_BLOCK_LUKS_SALT_LEN,
+                                       luks->header.key_bytes,
+                                       &local_err);
     if (local_err) {
         error_propagate(errp, local_err);
         goto error;
     }
-    /* Why /= 2 ?  That matches cryptsetup, but there's no
-     * explanation why they chose /= 2... */
-    luks->header.key_slots[0].iterations /= 2;
-    luks->header.key_slots[0].iterations = MAX(
-        luks->header.key_slots[0].iterations,
-        QCRYPTO_BLOCK_LUKS_MIN_SLOT_KEY_ITERS);
+
+    if (iters > (ULLONG_MAX / luks_opts.iter_time)) {
+        error_setg_errno(errp, ERANGE,
+                         "PBKDF iterations %llu too large to scale",
+                         (unsigned long long)iters);
+        goto error;
+    }
+
+    /* iter_time was in millis, but count_iters reported for secs */
+    iters = iters * luks_opts.iter_time / 1000;
+
+    if (iters > UINT32_MAX) {
+        error_setg_errno(errp, ERANGE,
+                         "PBKDF iterations %llu larger than %u",
+                         (unsigned long long)iters, UINT32_MAX);
+        goto error;
+    }
+
+    luks->header.key_slots[0].iterations =
+        MAX(iters, QCRYPTO_BLOCK_LUKS_MIN_SLOT_KEY_ITERS);
 
 
     /* Generate a key that we'll use to encrypt the master
@@ -1200,12 +1219,12 @@ qcrypto_block_luks_create(QCryptoBlock *block,
 
     /* Now we encrypt the split master key with the key generated
      * from the user's password, before storing it */
-    if (qcrypto_block_encrypt_helper(cipher, block->niv, ivgen,
-                                     QCRYPTO_BLOCK_LUKS_SECTOR_SIZE,
-                                     0,
-                                     splitkey,
-                                     splitkeylen,
-                                     errp) < 0) {
+    if (qcrypto_block_cipher_encrypt_helper(cipher, block->niv, ivgen,
+                                            QCRYPTO_BLOCK_LUKS_SECTOR_SIZE,
+                                            0,
+                                            splitkey,
+                                            splitkeylen,
+                                            errp) < 0) {
         goto error;
     }
 
@@ -1222,11 +1241,12 @@ qcrypto_block_luks_create(QCryptoBlock *block,
                    QCRYPTO_BLOCK_LUKS_SECTOR_SIZE)) *
          QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS);
 
+    block->sector_size = QCRYPTO_BLOCK_LUKS_SECTOR_SIZE;
     block->payload_offset = luks->header.payload_offset *
-        QCRYPTO_BLOCK_LUKS_SECTOR_SIZE;
+        block->sector_size;
 
     /* Reserve header space to match payload offset */
-    initfunc(block, block->payload_offset, &local_err, opaque);
+    initfunc(block, block->payload_offset, opaque, &local_err);
     if (local_err) {
         error_propagate(errp, local_err);
         goto error;
@@ -1251,8 +1271,8 @@ qcrypto_block_luks_create(QCryptoBlock *block,
     writefunc(block, 0,
               (const uint8_t *)&luks->header,
               sizeof(luks->header),
-              &local_err,
-              opaque);
+              opaque,
+              &local_err);
 
     /* Delay checking local_err until we've byte-swapped */
 
@@ -1281,8 +1301,8 @@ qcrypto_block_luks_create(QCryptoBlock *block,
                   luks->header.key_slots[0].key_offset *
                   QCRYPTO_BLOCK_LUKS_SECTOR_SIZE,
                   splitkey, splitkeylen,
-                  errp,
-                  opaque) != splitkeylen) {
+                  opaque,
+                  errp) != splitkeylen) {
         goto error;
     }
 
@@ -1321,6 +1341,9 @@ qcrypto_block_luks_create(QCryptoBlock *block,
     qcrypto_ivgen_free(ivgen);
     qcrypto_cipher_free(cipher);
 
+    qcrypto_cipher_free(block->cipher);
+    qcrypto_ivgen_free(block->ivgen);
+
     g_free(luks);
     return -1;
 }
@@ -1379,29 +1402,33 @@ static void qcrypto_block_luks_cleanup(QCryptoBlock *block)
 
 static int
 qcrypto_block_luks_decrypt(QCryptoBlock *block,
-                           uint64_t startsector,
+                           uint64_t offset,
                            uint8_t *buf,
                            size_t len,
                            Error **errp)
 {
-    return qcrypto_block_decrypt_helper(block->cipher,
-                                        block->niv, block->ivgen,
-                                        QCRYPTO_BLOCK_LUKS_SECTOR_SIZE,
-                                        startsector, buf, len, errp);
+    assert(QEMU_IS_ALIGNED(offset, QCRYPTO_BLOCK_LUKS_SECTOR_SIZE));
+    assert(QEMU_IS_ALIGNED(len, QCRYPTO_BLOCK_LUKS_SECTOR_SIZE));
+    return qcrypto_block_cipher_decrypt_helper(block->cipher,
+                                               block->niv, block->ivgen,
+                                               QCRYPTO_BLOCK_LUKS_SECTOR_SIZE,
+                                               offset, buf, len, errp);
 }
 
 
 static int
 qcrypto_block_luks_encrypt(QCryptoBlock *block,
-                           uint64_t startsector,
+                           uint64_t offset,
                            uint8_t *buf,
                            size_t len,
                            Error **errp)
 {
-    return qcrypto_block_encrypt_helper(block->cipher,
-                                        block->niv, block->ivgen,
-                                        QCRYPTO_BLOCK_LUKS_SECTOR_SIZE,
-                                        startsector, buf, len, errp);
+    assert(QEMU_IS_ALIGNED(offset, QCRYPTO_BLOCK_LUKS_SECTOR_SIZE));
+    assert(QEMU_IS_ALIGNED(len, QCRYPTO_BLOCK_LUKS_SECTOR_SIZE));
+    return qcrypto_block_cipher_encrypt_helper(block->cipher,
+                                               block->niv, block->ivgen,
+                                               QCRYPTO_BLOCK_LUKS_SECTOR_SIZE,
+                                               offset, buf, len, errp);
 }