Support empty salt for verity, support no superblock.
[platform/upstream/cryptsetup.git] / lib / libdevmapper.c
index 0174f1f..c82c0f5 100644 (file)
@@ -127,6 +127,16 @@ static void _dm_set_crypt_compat(const char *dm_version, unsigned crypt_maj,
                _dm_crypt_checked = 1;
 }
 
+static void _dm_set_verity_compat(const char *dm_version, unsigned verity_maj,
+                                  unsigned verity_min, unsigned verity_patch)
+{
+       if (verity_maj > 0)
+               _dm_crypt_flags |= DM_VERITY_SUPPORTED;
+
+       log_dbg("Detected dm-verity version %i.%i.%i.",
+               verity_maj, verity_min, verity_patch);
+}
+
 static int _dm_check_versions(void)
 {
        struct dm_task *dmt;
@@ -158,6 +168,11 @@ static int _dm_check_versions(void)
                                             (unsigned)target->version[0],
                                             (unsigned)target->version[1],
                                             (unsigned)target->version[2]);
+               } else if (!strcmp(DM_VERITY_TARGET, target->name)) {
+                       _dm_set_verity_compat(dm_version,
+                                            (unsigned)target->version[0],
+                                            (unsigned)target->version[1],
+                                            (unsigned)target->version[2]);
                }
                target = (struct dm_versions *)((char *) target + target->next);
        } while (last_target != target);
@@ -241,12 +256,31 @@ static void hex_key(char *hexkey, size_t key_size, const char *key)
                sprintf(&hexkey[i * 2], "%02x", (unsigned char)key[i]);
 }
 
+static int hex_to_bytes(const char *hex, char *result)
+{
+       char buf[3] = "xx\0", *endp;
+       int i, len;
+
+       len = strlen(hex) / 2;
+       for (i = 0; i < len; i++) {
+               memcpy(buf, &hex[i * 2], 2);
+               result[i] = strtoul(buf, &endp, 16);
+               if (endp != &buf[2])
+                       return -EINVAL;
+       }
+       return i;
+}
+
+/* http://code.google.com/p/cryptsetup/wiki/DMCrypt */
 static char *get_dm_crypt_params(struct crypt_dm_active_device *dmd)
 {
        int r, max_size, null_cipher = 0;
        char *params, *hexkey;
        const char *features = "";
 
+       if (!dmd)
+               return NULL;
+
        if (dmd->flags & CRYPT_ACTIVATE_ALLOW_DISCARDS) {
                if (dm_flags() & DM_DISCARDS_SUPPORTED) {
                        features = " 1 allow_discards";
@@ -255,27 +289,27 @@ static char *get_dm_crypt_params(struct crypt_dm_active_device *dmd)
                        log_dbg("Discard/TRIM is not supported by the kernel.");
        }
 
-       if (!strncmp(dmd->cipher, "cipher_null-", 12))
+       if (!strncmp(dmd->u.crypt.cipher, "cipher_null-", 12))
                null_cipher = 1;
 
-       hexkey = crypt_safe_alloc(null_cipher ? 2 : (dmd->vk->keylength * 2 + 1));
+       hexkey = crypt_safe_alloc(null_cipher ? 2 : (dmd->u.crypt.vk->keylength * 2 + 1));
        if (!hexkey)
                return NULL;
 
        if (null_cipher)
                strncpy(hexkey, "-", 2);
        else
-               hex_key(hexkey, dmd->vk->keylength, dmd->vk->key);
+               hex_key(hexkey, dmd->u.crypt.vk->keylength, dmd->u.crypt.vk->key);
 
-       max_size = strlen(hexkey) + strlen(dmd->cipher) +
-                  strlen(dmd->device) + strlen(features) + 64;
+       max_size = strlen(hexkey) + strlen(dmd->u.crypt.cipher) +
+                  strlen(dmd->data_device) + strlen(features) + 64;
        params = crypt_safe_alloc(max_size);
        if (!params)
                goto out;
 
        r = snprintf(params, max_size, "%s %s %" PRIu64 " %s %" PRIu64 "%s",
-                    dmd->cipher, hexkey, dmd->iv_offset, dmd->device,
-                    dmd->offset, features);
+                    dmd->u.crypt.cipher, hexkey, dmd->u.crypt.iv_offset,
+                    dmd->data_device, dmd->u.crypt.offset, features);
        if (r < 0 || r >= max_size) {
                crypt_safe_free(params);
                params = NULL;
@@ -284,24 +318,33 @@ out:
        crypt_safe_free(hexkey);
        return params;
 }
+
+/* http://code.google.com/p/cryptsetup/wiki/DMVerity */
 static char *get_dm_verity_params(struct crypt_params_verity *vp,
-                                  struct crypt_dm_active_verity *dmd)
+                                  struct crypt_dm_active_device *dmd)
 {
        int max_size, r;
        char *params = NULL, *hexroot = NULL, *hexsalt = NULL;
 
-       hexroot = crypt_safe_alloc(dmd->root_hash_size * 2 + 1);
+       if (!vp || !dmd)
+               return NULL;
+
+       hexroot = crypt_safe_alloc(dmd->u.verity.root_hash_size * 2 + 1);
        if (!hexroot)
                goto out;
-       hex_key(hexroot, dmd->root_hash_size, dmd->root_hash);
+       hex_key(hexroot, dmd->u.verity.root_hash_size, dmd->u.verity.root_hash);
 
-       hexsalt = crypt_safe_alloc(vp->salt_size * 2 + 1);
+       hexsalt = crypt_safe_alloc(vp->salt_size ? vp->salt_size * 2 + 1 : 2);
        if (!hexsalt)
                goto out;
-       hex_key(hexsalt, vp->salt_size, vp->salt);
+       if (vp->salt_size)
+               hex_key(hexsalt, vp->salt_size, vp->salt);
+       else
+               strncpy(hexsalt, "-", 2);
 
        max_size = strlen(hexroot) + strlen(hexsalt) +
-                  strlen(dmd->data_device) + strlen(dmd->hash_device) +
+                  strlen(dmd->data_device) +
+                  strlen(dmd->u.verity.hash_device) +
                   strlen(vp->hash_name) + 128;
 
        params = crypt_safe_alloc(max_size);
@@ -310,9 +353,10 @@ static char *get_dm_verity_params(struct crypt_params_verity *vp,
 
        r = snprintf(params, max_size,
                     "%u %s %s %u %u %" PRIu64 " %" PRIu64 " %s %s %s",
-                    vp->version, dmd->data_device, dmd->hash_device,
+                    vp->version, dmd->data_device,
+                    dmd->u.verity.hash_device,
                     vp->data_block_size, vp->hash_block_size,
-                    vp->data_size, dmd->hash_offset,
+                    vp->data_size, dmd->u.verity.hash_offset,
                     vp->hash_name, hexroot, hexsalt);
        if (r < 0 || r >= max_size) {
                crypt_safe_free(params);
@@ -568,26 +612,16 @@ int dm_create_device(const char *name,
 {
        char *table_params = NULL;
 
-       table_params = get_dm_crypt_params(dmd);
-       if (!table_params)
-               return -EINVAL;
-
-       return _dm_create_device(name, type, dmd->device, dmd->flags,
-                                dmd->uuid, dmd->size, table_params, reload);
-}
+       if (dmd->target == DM_CRYPT)
+               table_params = get_dm_crypt_params(dmd);
+       else if (dmd->target == DM_VERITY)
+               table_params = get_dm_verity_params(dmd->u.verity.vp, dmd);
 
-int dm_create_verity(const char *name,
-                    struct crypt_params_verity *params,
-                    struct crypt_dm_active_verity *dmd)
-{
-       char *table_params = NULL;
-
-       table_params = get_dm_verity_params(params, dmd);
        if (!table_params)
                return -EINVAL;
 
-       return _dm_create_device(name, CRYPT_VERITY, dmd->data_device, dmd->flags,
-                                NULL, dmd->size, table_params, 0);
+       return _dm_create_device(name, type, dmd->data_device, dmd->flags,
+                                dmd->uuid, dmd->size, table_params, reload);
 }
 
 static int dm_status_dmi(const char *name, struct dm_info *dmi,
@@ -618,11 +652,18 @@ static int dm_status_dmi(const char *name, struct dm_info *dmi,
 
        next = dm_get_next_target(dmt, next, &start, &length,
                                  &target_type, &params);
-       if (!target_type || strcmp(target_type, target) != 0 ||
-           start != 0 || next)
-               r = -EINVAL;
-       else
-               r = 0;
+
+       if (!target_type || start != 0 || next)
+               goto out;
+
+       if (target && strcmp(target_type, target))
+               goto out;
+
+       /* for target == NULL check all supported */
+       if (!target && (strcmp(target_type, DM_CRYPT_TARGET) &&
+                       strcmp(target_type, DM_VERITY_TARGET)))
+               goto out;
+       r = 0;
 out:
        if (!r && status_line && !(*status_line = strdup(params)))
                r = -ENOMEM;
@@ -638,7 +679,7 @@ int dm_status_device(const char *name)
        int r;
        struct dm_info dmi;
 
-       r = dm_status_dmi(name, &dmi, DM_CRYPT_TARGET, NULL);
+       r = dm_status_dmi(name, &dmi, NULL, NULL);
        if (r < 0)
                return r;
 
@@ -676,136 +717,264 @@ int dm_status_verity_ok(const char *name)
        return r;
 }
 
-int dm_query_device(const char *name, uint32_t get_flags,
-                   struct crypt_dm_active_device *dmd)
+/* FIXME use hex wrapper, user val wrappers for line parsing */
+static int _dm_query_crypt(uint32_t get_flags,
+                          struct dm_info *dmi,
+                          char *params,
+                          struct crypt_dm_active_device *dmd)
 {
-       struct dm_task *dmt;
-       struct dm_info dmi;
-       uint64_t start, length, val64;
-       char *target_type, *params, *rcipher, *key_, *rdevice, *endp, buffer[3], *arg;
-       const char *tmp_uuid;
-       void *next = NULL;
+       uint64_t val64;
+       char *rcipher, *key_, *rdevice, *endp, buffer[3], *arg;
        unsigned int i;
-       int r = -EINVAL;
 
        memset(dmd, 0, sizeof(*dmd));
-
-       if (!(dmt = dm_task_create(DM_DEVICE_TABLE)))
-               goto out;
-       if ((dm_flags() & DM_SECURE_SUPPORTED) && !dm_task_secure_data(dmt))
-               goto out;
-       if (!dm_task_set_name(dmt, name))
-               goto out;
-       r = -ENODEV;
-       if (!dm_task_run(dmt))
-               goto out;
-
-       r = -EINVAL;
-       if (!dm_task_get_info(dmt, &dmi))
-               goto out;
-
-       if (!dmi.exists) {
-               r = -ENODEV;
-               goto out;
-       }
-
-       tmp_uuid = dm_task_get_uuid(dmt);
-
-       next = dm_get_next_target(dmt, next, &start, &length,
-                                 &target_type, &params);
-       if (!target_type || strcmp(target_type, DM_CRYPT_TARGET) != 0 ||
-           start != 0 || next)
-               goto out;
-
-       dmd->size = length;
+       dmd->target = DM_CRYPT;
 
        rcipher = strsep(&params, " ");
        /* cipher */
-       if (get_flags & DM_ACTIVE_CIPHER)
-               dmd->cipher = strdup(rcipher);
+       if (get_flags & DM_ACTIVE_CRYPT_CIPHER)
+               dmd->u.crypt.cipher = strdup(rcipher);
 
        /* skip */
        key_ = strsep(&params, " ");
        if (!params)
-               goto out;
+               return -EINVAL;
        val64 = strtoull(params, &params, 10);
        if (*params != ' ')
-               goto out;
+               return -EINVAL;
        params++;
 
-       dmd->iv_offset = val64;
+       dmd->u.crypt.iv_offset = val64;
 
        /* device */
        rdevice = strsep(&params, " ");
        if (get_flags & DM_ACTIVE_DEVICE)
-               dmd->device = crypt_lookup_dev(rdevice);
+               dmd->data_device = crypt_lookup_dev(rdevice);
 
        /*offset */
        if (!params)
-               goto out;
+               return -EINVAL;
        val64 = strtoull(params, &params, 10);
-       dmd->offset = val64;
+       dmd->u.crypt.offset = val64;
 
        /* Features section, available since crypt target version 1.11 */
        if (*params) {
                if (*params != ' ')
-                       goto out;
+                       return -EINVAL;
                params++;
 
                /* Number of arguments */
                val64 = strtoull(params, &params, 10);
                if (*params != ' ')
-                       goto out;
+                       return -EINVAL;
                params++;
 
                for (i = 0; i < val64; i++) {
                        if (!params)
-                               goto out;
+                               return -EINVAL;
                        arg = strsep(&params, " ");
                        if (!strcasecmp(arg, "allow_discards"))
                                dmd->flags |= CRYPT_ACTIVATE_ALLOW_DISCARDS;
                        else /* unknown option */
-                               goto out;
+                               return -EINVAL;
                }
 
                /* All parameters shold be processed */
                if (params)
-                       goto out;
+                       return -EINVAL;
        }
 
        /* Never allow to return empty key */
-       if ((get_flags & DM_ACTIVE_KEY) && dmi.suspended) {
+       if ((get_flags & DM_ACTIVE_CRYPT_KEY) && dmi->suspended) {
                log_dbg("Cannot read volume key while suspended.");
-               r = -EINVAL;
-               goto out;
+               return -EINVAL;
        }
 
-       if (get_flags & DM_ACTIVE_KEYSIZE) {
-               dmd->vk = crypt_alloc_volume_key(strlen(key_) / 2, NULL);
-               if (!dmd->vk) {
-                       r = -ENOMEM;
-                       goto out;
-               }
+       if (get_flags & DM_ACTIVE_CRYPT_KEYSIZE) {
+               dmd->u.crypt.vk = crypt_alloc_volume_key(strlen(key_) / 2, NULL);
+               if (!dmd->u.crypt.vk)
+                       return -ENOMEM;
 
-               if (get_flags & DM_ACTIVE_KEY) {
+               if (get_flags & DM_ACTIVE_CRYPT_KEY) {
                        buffer[2] = '\0';
-                       for(i = 0; i < dmd->vk->keylength; i++) {
+                       for(i = 0; i < dmd->u.crypt.vk->keylength; i++) {
                                memcpy(buffer, &key_[i * 2], 2);
-                               dmd->vk->key[i] = strtoul(buffer, &endp, 16);
+                               dmd->u.crypt.vk->key[i] = strtoul(buffer, &endp, 16);
                                if (endp != &buffer[2]) {
-                                       crypt_free_volume_key(dmd->vk);
-                                       dmd->vk = NULL;
-                                       r = -EINVAL;
-                                       goto out;
+                                       crypt_free_volume_key(dmd->u.crypt.vk);
+                                       dmd->u.crypt.vk = NULL;
+                                       return -EINVAL;
                                }
                        }
                }
        }
        memset(key_, 0, strlen(key_));
 
+       return 0;
+}
+
+static int _dm_query_verity(uint32_t get_flags,
+                            struct dm_info *dmi,
+                            char *params,
+                            struct crypt_dm_active_device *dmd)
+{
+       struct crypt_params_verity *vp = NULL;
+       uint32_t val32;
+       uint64_t val64;
+       size_t len;
+       char *str, *str2;
+
+       if (get_flags & DM_ACTIVE_VERITY_PARAMS)
+               vp = dmd->u.verity.vp;
+
+       memset(dmd, 0, sizeof(*dmd));
+
+       dmd->target = DM_VERITY;
+       dmd->u.verity.vp = vp;
+
+       /* version */
+       val32 = strtoul(params, &params, 10);
+       if (*params != ' ')
+               return -EINVAL;
+       if (vp)
+               vp->version = val32;
+       params++;
+
+       /* data device */
+       str = strsep(&params, " ");
+       if (!params)
+               return -EINVAL;
+       if (get_flags & DM_ACTIVE_DEVICE)
+               dmd->data_device = crypt_lookup_dev(str);
+
+       /* hash device */
+       str = strsep(&params, " ");
+       if (!params)
+               return -EINVAL;
+       if (get_flags & DM_ACTIVE_VERITY_HASH_DEVICE)
+               dmd->u.verity.hash_device = crypt_lookup_dev(str);
+
+       /* data block size*/
+       val32 = strtoul(params, &params, 10);
+       if (*params != ' ')
+               return -EINVAL;
+       if (vp)
+               vp->data_block_size = val32;
+       params++;
+
+       /* hash block size */
+       val32 = strtoul(params, &params, 10);
+       if (*params != ' ')
+               return -EINVAL;
+       if (vp)
+               vp->hash_block_size = val32;
+       params++;
+
+       /* data blocks */
+       val64 = strtoull(params, &params, 10);
+       if (*params != ' ')
+               return -EINVAL;
+       if (vp)
+               vp->data_size = val64;
+       params++;
+
+       /* hash start */
+       val64 = strtoull(params, &params, 10);
+       if (*params != ' ')
+               return -EINVAL;
+       dmd->u.verity.hash_offset = val64;
+       params++;
+
+       /* hash algorithm */
+       str = strsep(&params, " ");
+       if (!params)
+               return -EINVAL;
+       if (vp)
+               vp->hash_name = strdup(str);
+
+       /* root digest */
+       str = strsep(&params, " ");
+       if (!params)
+               return -EINVAL;
+       len = strlen(str) / 2;
+       dmd->u.verity.root_hash_size = len;
+       if (get_flags & DM_ACTIVE_VERITY_ROOT_HASH) {
+               if (!(str2 = malloc(len)))
+                       return -ENOMEM;
+               if (hex_to_bytes(str, str2) != len)
+                       return -EINVAL;
+               dmd->u.verity.root_hash = str2;
+       }
+
+       /* salt */
+       str = strsep(&params, " ");
+       if (params)
+               return -EINVAL;
+       if (vp) {
+               len = strlen(str) / 2;
+               vp->salt_size = len;
+               if (!(str2 = malloc(len)))
+                       return -ENOMEM;
+               if (hex_to_bytes(str, str2) != len)
+                       return -EINVAL;
+               vp->salt = str2;
+       }
+
+       return 0;
+}
+
+int dm_query_device(const char *name, uint32_t get_flags,
+                   struct crypt_dm_active_device *dmd)
+{
+       struct dm_task *dmt;
+       struct dm_info dmi;
+       uint64_t start, length;
+       char *target_type, *params;
+       const char *tmp_uuid;
+       void *next = NULL;
+       int r = -EINVAL;
+
+       if (!(dmt = dm_task_create(DM_DEVICE_TABLE)))
+               goto out;
+       if ((dm_flags() & DM_SECURE_SUPPORTED) && !dm_task_secure_data(dmt))
+               goto out;
+       if (!dm_task_set_name(dmt, name))
+               goto out;
+       r = -ENODEV;
+       if (!dm_task_run(dmt))
+               goto out;
+
+       r = -EINVAL;
+       if (!dm_task_get_info(dmt, &dmi))
+               goto out;
+
+       if (!dmi.exists) {
+               r = -ENODEV;
+               goto out;
+       }
+
+       next = dm_get_next_target(dmt, next, &start, &length,
+                                 &target_type, &params);
+
+       if (!target_type || start != 0 || next)
+               goto out;
+
+       if (!strcmp(target_type, DM_CRYPT_TARGET))
+               r = _dm_query_crypt(get_flags, &dmi, params, dmd);
+       else if (!strcmp(target_type, DM_VERITY_TARGET))
+               r = _dm_query_verity(get_flags, &dmi, params, dmd);
+       else
+               r = -EINVAL;
+
+       if (r < 0)
+               goto out;
+
+       dmd->size = length;
+
        if (dmi.read_only)
                dmd->flags |= CRYPT_ACTIVATE_READONLY;
 
+       tmp_uuid = dm_task_get_uuid(dmt);
        if (!tmp_uuid)
                dmd->flags |= CRYPT_ACTIVATE_NO_UUID;
        else if (get_flags & DM_ACTIVE_UUID) {
@@ -821,14 +990,6 @@ out:
        return r;
 }
 
-int dm_query_verity(const char *name,
-                   struct crypt_dm_active_verity *dmd)
-{
-       int r = -EINVAL;
-
-       return r;
-}
-
 static int _dm_message(const char *name, const char *msg)
 {
        int r = 0;
@@ -931,13 +1092,14 @@ int dm_check_segment(const char *name, uint64_t offset, uint64_t size)
        if (r < 0)
                return r;
 
-       if (offset >= (dmd.offset + dmd.size) || (offset + size) <= dmd.offset)
+       if (offset >= (dmd.u.crypt.offset + dmd.size) ||
+          (offset + size) <= dmd.u.crypt.offset)
                r = 0;
        else
                r = -EBUSY;
 
        log_dbg("seg: %" PRIu64 " - %" PRIu64 ", new %" PRIu64 " - %" PRIu64 "%s",
-              dmd.offset, dmd.offset + dmd.size, offset, offset + size,
+              dmd.u.crypt.offset, dmd.u.crypt.offset + dmd.size, offset, offset + size,
               r ? " (overlapping)" : " (ok)");
 
        return r;