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-rw-r--r--fs/bcachefs/checksum.c804
1 files changed, 804 insertions, 0 deletions
diff --git a/fs/bcachefs/checksum.c b/fs/bcachefs/checksum.c
new file mode 100644
index 000000000000..3c761ad6b1c8
--- /dev/null
+++ b/fs/bcachefs/checksum.c
@@ -0,0 +1,804 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "bcachefs.h"
+#include "checksum.h"
+#include "errcode.h"
+#include "super.h"
+#include "super-io.h"
+
+#include <linux/crc32c.h>
+#include <linux/crypto.h>
+#include <linux/xxhash.h>
+#include <linux/key.h>
+#include <linux/random.h>
+#include <linux/scatterlist.h>
+#include <crypto/algapi.h>
+#include <crypto/chacha.h>
+#include <crypto/hash.h>
+#include <crypto/poly1305.h>
+#include <crypto/skcipher.h>
+#include <keys/user-type.h>
+
+/*
+ * bch2_checksum state is an abstraction of the checksum state calculated over different pages.
+ * it features page merging without having the checksum algorithm lose its state.
+ * for native checksum aglorithms (like crc), a default seed value will do.
+ * for hash-like algorithms, a state needs to be stored
+ */
+
+struct bch2_checksum_state {
+ union {
+ u64 seed;
+ struct xxh64_state h64state;
+ };
+ unsigned int type;
+};
+
+static void bch2_checksum_init(struct bch2_checksum_state *state)
+{
+ switch (state->type) {
+ case BCH_CSUM_none:
+ case BCH_CSUM_crc32c:
+ case BCH_CSUM_crc64:
+ state->seed = 0;
+ break;
+ case BCH_CSUM_crc32c_nonzero:
+ state->seed = U32_MAX;
+ break;
+ case BCH_CSUM_crc64_nonzero:
+ state->seed = U64_MAX;
+ break;
+ case BCH_CSUM_xxhash:
+ xxh64_reset(&state->h64state, 0);
+ break;
+ default:
+ BUG();
+ }
+}
+
+static u64 bch2_checksum_final(const struct bch2_checksum_state *state)
+{
+ switch (state->type) {
+ case BCH_CSUM_none:
+ case BCH_CSUM_crc32c:
+ case BCH_CSUM_crc64:
+ return state->seed;
+ case BCH_CSUM_crc32c_nonzero:
+ return state->seed ^ U32_MAX;
+ case BCH_CSUM_crc64_nonzero:
+ return state->seed ^ U64_MAX;
+ case BCH_CSUM_xxhash:
+ return xxh64_digest(&state->h64state);
+ default:
+ BUG();
+ }
+}
+
+static void bch2_checksum_update(struct bch2_checksum_state *state, const void *data, size_t len)
+{
+ switch (state->type) {
+ case BCH_CSUM_none:
+ return;
+ case BCH_CSUM_crc32c_nonzero:
+ case BCH_CSUM_crc32c:
+ state->seed = crc32c(state->seed, data, len);
+ break;
+ case BCH_CSUM_crc64_nonzero:
+ case BCH_CSUM_crc64:
+ state->seed = crc64_be(state->seed, data, len);
+ break;
+ case BCH_CSUM_xxhash:
+ xxh64_update(&state->h64state, data, len);
+ break;
+ default:
+ BUG();
+ }
+}
+
+static inline int do_encrypt_sg(struct crypto_sync_skcipher *tfm,
+ struct nonce nonce,
+ struct scatterlist *sg, size_t len)
+{
+ SYNC_SKCIPHER_REQUEST_ON_STACK(req, tfm);
+ int ret;
+
+ skcipher_request_set_sync_tfm(req, tfm);
+ skcipher_request_set_crypt(req, sg, sg, len, nonce.d);
+
+ ret = crypto_skcipher_encrypt(req);
+ if (ret)
+ pr_err("got error %i from crypto_skcipher_encrypt()", ret);
+
+ return ret;
+}
+
+static inline int do_encrypt(struct crypto_sync_skcipher *tfm,
+ struct nonce nonce,
+ void *buf, size_t len)
+{
+ if (!is_vmalloc_addr(buf)) {
+ struct scatterlist sg;
+
+ sg_init_table(&sg, 1);
+ sg_set_page(&sg,
+ is_vmalloc_addr(buf)
+ ? vmalloc_to_page(buf)
+ : virt_to_page(buf),
+ len, offset_in_page(buf));
+ return do_encrypt_sg(tfm, nonce, &sg, len);
+ } else {
+ unsigned pages = buf_pages(buf, len);
+ struct scatterlist *sg;
+ size_t orig_len = len;
+ int ret, i;
+
+ sg = kmalloc_array(pages, sizeof(*sg), GFP_KERNEL);
+ if (!sg)
+ return -BCH_ERR_ENOMEM_do_encrypt;
+
+ sg_init_table(sg, pages);
+
+ for (i = 0; i < pages; i++) {
+ unsigned offset = offset_in_page(buf);
+ unsigned pg_len = min_t(size_t, len, PAGE_SIZE - offset);
+
+ sg_set_page(sg + i, vmalloc_to_page(buf), pg_len, offset);
+ buf += pg_len;
+ len -= pg_len;
+ }
+
+ ret = do_encrypt_sg(tfm, nonce, sg, orig_len);
+ kfree(sg);
+ return ret;
+ }
+}
+
+int bch2_chacha_encrypt_key(struct bch_key *key, struct nonce nonce,
+ void *buf, size_t len)
+{
+ struct crypto_sync_skcipher *chacha20 =
+ crypto_alloc_sync_skcipher("chacha20", 0, 0);
+ int ret;
+
+ ret = PTR_ERR_OR_ZERO(chacha20);
+ if (ret) {
+ pr_err("error requesting chacha20 cipher: %s", bch2_err_str(ret));
+ return ret;
+ }
+
+ ret = crypto_skcipher_setkey(&chacha20->base,
+ (void *) key, sizeof(*key));
+ if (ret) {
+ pr_err("error from crypto_skcipher_setkey(): %s", bch2_err_str(ret));
+ goto err;
+ }
+
+ ret = do_encrypt(chacha20, nonce, buf, len);
+err:
+ crypto_free_sync_skcipher(chacha20);
+ return ret;
+}
+
+static int gen_poly_key(struct bch_fs *c, struct shash_desc *desc,
+ struct nonce nonce)
+{
+ u8 key[POLY1305_KEY_SIZE];
+ int ret;
+
+ nonce.d[3] ^= BCH_NONCE_POLY;
+
+ memset(key, 0, sizeof(key));
+ ret = do_encrypt(c->chacha20, nonce, key, sizeof(key));
+ if (ret)
+ return ret;
+
+ desc->tfm = c->poly1305;
+ crypto_shash_init(desc);
+ crypto_shash_update(desc, key, sizeof(key));
+ return 0;
+}
+
+struct bch_csum bch2_checksum(struct bch_fs *c, unsigned type,
+ struct nonce nonce, const void *data, size_t len)
+{
+ switch (type) {
+ case BCH_CSUM_none:
+ case BCH_CSUM_crc32c_nonzero:
+ case BCH_CSUM_crc64_nonzero:
+ case BCH_CSUM_crc32c:
+ case BCH_CSUM_xxhash:
+ case BCH_CSUM_crc64: {
+ struct bch2_checksum_state state;
+
+ state.type = type;
+
+ bch2_checksum_init(&state);
+ bch2_checksum_update(&state, data, len);
+
+ return (struct bch_csum) { .lo = cpu_to_le64(bch2_checksum_final(&state)) };
+ }
+
+ case BCH_CSUM_chacha20_poly1305_80:
+ case BCH_CSUM_chacha20_poly1305_128: {
+ SHASH_DESC_ON_STACK(desc, c->poly1305);
+ u8 digest[POLY1305_DIGEST_SIZE];
+ struct bch_csum ret = { 0 };
+
+ gen_poly_key(c, desc, nonce);
+
+ crypto_shash_update(desc, data, len);
+ crypto_shash_final(desc, digest);
+
+ memcpy(&ret, digest, bch_crc_bytes[type]);
+ return ret;
+ }
+ default:
+ BUG();
+ }
+}
+
+int bch2_encrypt(struct bch_fs *c, unsigned type,
+ struct nonce nonce, void *data, size_t len)
+{
+ if (!bch2_csum_type_is_encryption(type))
+ return 0;
+
+ return do_encrypt(c->chacha20, nonce, data, len);
+}
+
+static struct bch_csum __bch2_checksum_bio(struct bch_fs *c, unsigned type,
+ struct nonce nonce, struct bio *bio,
+ struct bvec_iter *iter)
+{
+ struct bio_vec bv;
+
+ switch (type) {
+ case BCH_CSUM_none:
+ return (struct bch_csum) { 0 };
+ case BCH_CSUM_crc32c_nonzero:
+ case BCH_CSUM_crc64_nonzero:
+ case BCH_CSUM_crc32c:
+ case BCH_CSUM_xxhash:
+ case BCH_CSUM_crc64: {
+ struct bch2_checksum_state state;
+
+ state.type = type;
+ bch2_checksum_init(&state);
+
+#ifdef CONFIG_HIGHMEM
+ __bio_for_each_segment(bv, bio, *iter, *iter) {
+ void *p = kmap_local_page(bv.bv_page) + bv.bv_offset;
+
+ bch2_checksum_update(&state, p, bv.bv_len);
+ kunmap_local(p);
+ }
+#else
+ __bio_for_each_bvec(bv, bio, *iter, *iter)
+ bch2_checksum_update(&state, page_address(bv.bv_page) + bv.bv_offset,
+ bv.bv_len);
+#endif
+ return (struct bch_csum) { .lo = cpu_to_le64(bch2_checksum_final(&state)) };
+ }
+
+ case BCH_CSUM_chacha20_poly1305_80:
+ case BCH_CSUM_chacha20_poly1305_128: {
+ SHASH_DESC_ON_STACK(desc, c->poly1305);
+ u8 digest[POLY1305_DIGEST_SIZE];
+ struct bch_csum ret = { 0 };
+
+ gen_poly_key(c, desc, nonce);
+
+#ifdef CONFIG_HIGHMEM
+ __bio_for_each_segment(bv, bio, *iter, *iter) {
+ void *p = kmap_local_page(bv.bv_page) + bv.bv_offset;
+
+ crypto_shash_update(desc, p, bv.bv_len);
+ kunmap_local(p);
+ }
+#else
+ __bio_for_each_bvec(bv, bio, *iter, *iter)
+ crypto_shash_update(desc,
+ page_address(bv.bv_page) + bv.bv_offset,
+ bv.bv_len);
+#endif
+ crypto_shash_final(desc, digest);
+
+ memcpy(&ret, digest, bch_crc_bytes[type]);
+ return ret;
+ }
+ default:
+ BUG();
+ }
+}
+
+struct bch_csum bch2_checksum_bio(struct bch_fs *c, unsigned type,
+ struct nonce nonce, struct bio *bio)
+{
+ struct bvec_iter iter = bio->bi_iter;
+
+ return __bch2_checksum_bio(c, type, nonce, bio, &iter);
+}
+
+int __bch2_encrypt_bio(struct bch_fs *c, unsigned type,
+ struct nonce nonce, struct bio *bio)
+{
+ struct bio_vec bv;
+ struct bvec_iter iter;
+ struct scatterlist sgl[16], *sg = sgl;
+ size_t bytes = 0;
+ int ret = 0;
+
+ if (!bch2_csum_type_is_encryption(type))
+ return 0;
+
+ sg_init_table(sgl, ARRAY_SIZE(sgl));
+
+ bio_for_each_segment(bv, bio, iter) {
+ if (sg == sgl + ARRAY_SIZE(sgl)) {
+ sg_mark_end(sg - 1);
+
+ ret = do_encrypt_sg(c->chacha20, nonce, sgl, bytes);
+ if (ret)
+ return ret;
+
+ nonce = nonce_add(nonce, bytes);
+ bytes = 0;
+
+ sg_init_table(sgl, ARRAY_SIZE(sgl));
+ sg = sgl;
+ }
+
+ sg_set_page(sg++, bv.bv_page, bv.bv_len, bv.bv_offset);
+ bytes += bv.bv_len;
+ }
+
+ sg_mark_end(sg - 1);
+ return do_encrypt_sg(c->chacha20, nonce, sgl, bytes);
+}
+
+struct bch_csum bch2_checksum_merge(unsigned type, struct bch_csum a,
+ struct bch_csum b, size_t b_len)
+{
+ struct bch2_checksum_state state;
+
+ state.type = type;
+ bch2_checksum_init(&state);
+ state.seed = le64_to_cpu(a.lo);
+
+ BUG_ON(!bch2_checksum_mergeable(type));
+
+ while (b_len) {
+ unsigned page_len = min_t(unsigned, b_len, PAGE_SIZE);
+
+ bch2_checksum_update(&state,
+ page_address(ZERO_PAGE(0)), page_len);
+ b_len -= page_len;
+ }
+ a.lo = cpu_to_le64(bch2_checksum_final(&state));
+ a.lo ^= b.lo;
+ a.hi ^= b.hi;
+ return a;
+}
+
+int bch2_rechecksum_bio(struct bch_fs *c, struct bio *bio,
+ struct bversion version,
+ struct bch_extent_crc_unpacked crc_old,
+ struct bch_extent_crc_unpacked *crc_a,
+ struct bch_extent_crc_unpacked *crc_b,
+ unsigned len_a, unsigned len_b,
+ unsigned new_csum_type)
+{
+ struct bvec_iter iter = bio->bi_iter;
+ struct nonce nonce = extent_nonce(version, crc_old);
+ struct bch_csum merged = { 0 };
+ struct crc_split {
+ struct bch_extent_crc_unpacked *crc;
+ unsigned len;
+ unsigned csum_type;
+ struct bch_csum csum;
+ } splits[3] = {
+ { crc_a, len_a, new_csum_type, { 0 }},
+ { crc_b, len_b, new_csum_type, { 0 } },
+ { NULL, bio_sectors(bio) - len_a - len_b, new_csum_type, { 0 } },
+ }, *i;
+ bool mergeable = crc_old.csum_type == new_csum_type &&
+ bch2_checksum_mergeable(new_csum_type);
+ unsigned crc_nonce = crc_old.nonce;
+
+ BUG_ON(len_a + len_b > bio_sectors(bio));
+ BUG_ON(crc_old.uncompressed_size != bio_sectors(bio));
+ BUG_ON(crc_is_compressed(crc_old));
+ BUG_ON(bch2_csum_type_is_encryption(crc_old.csum_type) !=
+ bch2_csum_type_is_encryption(new_csum_type));
+
+ for (i = splits; i < splits + ARRAY_SIZE(splits); i++) {
+ iter.bi_size = i->len << 9;
+ if (mergeable || i->crc)
+ i->csum = __bch2_checksum_bio(c, i->csum_type,
+ nonce, bio, &iter);
+ else
+ bio_advance_iter(bio, &iter, i->len << 9);
+ nonce = nonce_add(nonce, i->len << 9);
+ }
+
+ if (mergeable)
+ for (i = splits; i < splits + ARRAY_SIZE(splits); i++)
+ merged = bch2_checksum_merge(new_csum_type, merged,
+ i->csum, i->len << 9);
+ else
+ merged = bch2_checksum_bio(c, crc_old.csum_type,
+ extent_nonce(version, crc_old), bio);
+
+ if (bch2_crc_cmp(merged, crc_old.csum) && !c->opts.no_data_io) {
+ bch_err(c, "checksum error in %s() (memory corruption or bug?)\n"
+ "expected %0llx:%0llx got %0llx:%0llx (old type %s new type %s)",
+ __func__,
+ crc_old.csum.hi,
+ crc_old.csum.lo,
+ merged.hi,
+ merged.lo,
+ bch2_csum_types[crc_old.csum_type],
+ bch2_csum_types[new_csum_type]);
+ return -EIO;
+ }
+
+ for (i = splits; i < splits + ARRAY_SIZE(splits); i++) {
+ if (i->crc)
+ *i->crc = (struct bch_extent_crc_unpacked) {
+ .csum_type = i->csum_type,
+ .compression_type = crc_old.compression_type,
+ .compressed_size = i->len,
+ .uncompressed_size = i->len,
+ .offset = 0,
+ .live_size = i->len,
+ .nonce = crc_nonce,
+ .csum = i->csum,
+ };
+
+ if (bch2_csum_type_is_encryption(new_csum_type))
+ crc_nonce += i->len;
+ }
+
+ return 0;
+}
+
+/* BCH_SB_FIELD_crypt: */
+
+static int bch2_sb_crypt_validate(struct bch_sb *sb,
+ struct bch_sb_field *f,
+ struct printbuf *err)
+{
+ struct bch_sb_field_crypt *crypt = field_to_type(f, crypt);
+
+ if (vstruct_bytes(&crypt->field) < sizeof(*crypt)) {
+ prt_printf(err, "wrong size (got %zu should be %zu)",
+ vstruct_bytes(&crypt->field), sizeof(*crypt));
+ return -BCH_ERR_invalid_sb_crypt;
+ }
+
+ if (BCH_CRYPT_KDF_TYPE(crypt)) {
+ prt_printf(err, "bad kdf type %llu", BCH_CRYPT_KDF_TYPE(crypt));
+ return -BCH_ERR_invalid_sb_crypt;
+ }
+
+ return 0;
+}
+
+static void bch2_sb_crypt_to_text(struct printbuf *out, struct bch_sb *sb,
+ struct bch_sb_field *f)
+{
+ struct bch_sb_field_crypt *crypt = field_to_type(f, crypt);
+
+ prt_printf(out, "KFD: %llu", BCH_CRYPT_KDF_TYPE(crypt));
+ prt_newline(out);
+ prt_printf(out, "scrypt n: %llu", BCH_KDF_SCRYPT_N(crypt));
+ prt_newline(out);
+ prt_printf(out, "scrypt r: %llu", BCH_KDF_SCRYPT_R(crypt));
+ prt_newline(out);
+ prt_printf(out, "scrypt p: %llu", BCH_KDF_SCRYPT_P(crypt));
+ prt_newline(out);
+}
+
+const struct bch_sb_field_ops bch_sb_field_ops_crypt = {
+ .validate = bch2_sb_crypt_validate,
+ .to_text = bch2_sb_crypt_to_text,
+};
+
+#ifdef __KERNEL__
+static int __bch2_request_key(char *key_description, struct bch_key *key)
+{
+ struct key *keyring_key;
+ const struct user_key_payload *ukp;
+ int ret;
+
+ keyring_key = request_key(&key_type_user, key_description, NULL);
+ if (IS_ERR(keyring_key))
+ return PTR_ERR(keyring_key);
+
+ down_read(&keyring_key->sem);
+ ukp = dereference_key_locked(keyring_key);
+ if (ukp->datalen == sizeof(*key)) {
+ memcpy(key, ukp->data, ukp->datalen);
+ ret = 0;
+ } else {
+ ret = -EINVAL;
+ }
+ up_read(&keyring_key->sem);
+ key_put(keyring_key);
+
+ return ret;
+}
+#else
+#include <keyutils.h>
+
+static int __bch2_request_key(char *key_description, struct bch_key *key)
+{
+ key_serial_t key_id;
+
+ key_id = request_key("user", key_description, NULL,
+ KEY_SPEC_SESSION_KEYRING);
+ if (key_id >= 0)
+ goto got_key;
+
+ key_id = request_key("user", key_description, NULL,
+ KEY_SPEC_USER_KEYRING);
+ if (key_id >= 0)
+ goto got_key;
+
+ key_id = request_key("user", key_description, NULL,
+ KEY_SPEC_USER_SESSION_KEYRING);
+ if (key_id >= 0)
+ goto got_key;
+
+ return -errno;
+got_key:
+
+ if (keyctl_read(key_id, (void *) key, sizeof(*key)) != sizeof(*key))
+ return -1;
+
+ return 0;
+}
+
+#include "../crypto.h"
+#endif
+
+int bch2_request_key(struct bch_sb *sb, struct bch_key *key)
+{
+ struct printbuf key_description = PRINTBUF;
+ int ret;
+
+ prt_printf(&key_description, "bcachefs:");
+ pr_uuid(&key_description, sb->user_uuid.b);
+
+ ret = __bch2_request_key(key_description.buf, key);
+ printbuf_exit(&key_description);
+
+#ifndef __KERNEL__
+ if (ret) {
+ char *passphrase = read_passphrase("Enter passphrase: ");
+ struct bch_encrypted_key sb_key;
+
+ bch2_passphrase_check(sb, passphrase,
+ key, &sb_key);
+ ret = 0;
+ }
+#endif
+
+ /* stash with memfd, pass memfd fd to mount */
+
+ return ret;
+}
+
+#ifndef __KERNEL__
+int bch2_revoke_key(struct bch_sb *sb)
+{
+ key_serial_t key_id;
+ struct printbuf key_description = PRINTBUF;
+
+ prt_printf(&key_description, "bcachefs:");
+ pr_uuid(&key_description, sb->user_uuid.b);
+
+ key_id = request_key("user", key_description.buf, NULL, KEY_SPEC_USER_KEYRING);
+ printbuf_exit(&key_description);
+ if (key_id < 0)
+ return errno;
+
+ keyctl_revoke(key_id);
+
+ return 0;
+}
+#endif
+
+int bch2_decrypt_sb_key(struct bch_fs *c,
+ struct bch_sb_field_crypt *crypt,
+ struct bch_key *key)
+{
+ struct bch_encrypted_key sb_key = crypt->key;
+ struct bch_key user_key;
+ int ret = 0;
+
+ /* is key encrypted? */
+ if (!bch2_key_is_encrypted(&sb_key))
+ goto out;
+
+ ret = bch2_request_key(c->disk_sb.sb, &user_key);
+ if (ret) {
+ bch_err(c, "error requesting encryption key: %s", bch2_err_str(ret));
+ goto err;
+ }
+
+ /* decrypt real key: */
+ ret = bch2_chacha_encrypt_key(&user_key, bch2_sb_key_nonce(c),
+ &sb_key, sizeof(sb_key));
+ if (ret)
+ goto err;
+
+ if (bch2_key_is_encrypted(&sb_key)) {
+ bch_err(c, "incorrect encryption key");
+ ret = -EINVAL;
+ goto err;
+ }
+out:
+ *key = sb_key.key;
+err:
+ memzero_explicit(&sb_key, sizeof(sb_key));
+ memzero_explicit(&user_key, sizeof(user_key));
+ return ret;
+}
+
+static int bch2_alloc_ciphers(struct bch_fs *c)
+{
+ int ret;
+
+ if (!c->chacha20)
+ c->chacha20 = crypto_alloc_sync_skcipher("chacha20", 0, 0);
+ ret = PTR_ERR_OR_ZERO(c->chacha20);
+
+ if (ret) {
+ bch_err(c, "error requesting chacha20 module: %s", bch2_err_str(ret));
+ return ret;
+ }
+
+ if (!c->poly1305)
+ c->poly1305 = crypto_alloc_shash("poly1305", 0, 0);
+ ret = PTR_ERR_OR_ZERO(c->poly1305);
+
+ if (ret) {
+ bch_err(c, "error requesting poly1305 module: %s", bch2_err_str(ret));
+ return ret;
+ }
+
+ return 0;
+}
+
+int bch2_disable_encryption(struct bch_fs *c)
+{
+ struct bch_sb_field_crypt *crypt;
+ struct bch_key key;
+ int ret = -EINVAL;
+
+ mutex_lock(&c->sb_lock);
+
+ crypt = bch2_sb_field_get(c->disk_sb.sb, crypt);
+ if (!crypt)
+ goto out;
+
+ /* is key encrypted? */
+ ret = 0;
+ if (bch2_key_is_encrypted(&crypt->key))
+ goto out;
+
+ ret = bch2_decrypt_sb_key(c, crypt, &key);
+ if (ret)
+ goto out;
+
+ crypt->key.magic = cpu_to_le64(BCH_KEY_MAGIC);
+ crypt->key.key = key;
+
+ SET_BCH_SB_ENCRYPTION_TYPE(c->disk_sb.sb, 0);
+ bch2_write_super(c);
+out:
+ mutex_unlock(&c->sb_lock);
+
+ return ret;
+}
+
+int bch2_enable_encryption(struct bch_fs *c, bool keyed)
+{
+ struct bch_encrypted_key key;
+ struct bch_key user_key;
+ struct bch_sb_field_crypt *crypt;
+ int ret = -EINVAL;
+
+ mutex_lock(&c->sb_lock);
+
+ /* Do we already have an encryption key? */
+ if (bch2_sb_field_get(c->disk_sb.sb, crypt))
+ goto err;
+
+ ret = bch2_alloc_ciphers(c);
+ if (ret)
+ goto err;
+
+ key.magic = cpu_to_le64(BCH_KEY_MAGIC);
+ get_random_bytes(&key.key, sizeof(key.key));
+
+ if (keyed) {
+ ret = bch2_request_key(c->disk_sb.sb, &user_key);
+ if (ret) {
+ bch_err(c, "error requesting encryption key: %s", bch2_err_str(ret));
+ goto err;
+ }
+
+ ret = bch2_chacha_encrypt_key(&user_key, bch2_sb_key_nonce(c),
+ &key, sizeof(key));
+ if (ret)
+ goto err;
+ }
+
+ ret = crypto_skcipher_setkey(&c->chacha20->base,
+ (void *) &key.key, sizeof(key.key));
+ if (ret)
+ goto err;
+
+ crypt = bch2_sb_field_resize(&c->disk_sb, crypt,
+ sizeof(*crypt) / sizeof(u64));
+ if (!crypt) {
+ ret = -BCH_ERR_ENOSPC_sb_crypt;
+ goto err;
+ }
+
+ crypt->key = key;
+
+ /* write superblock */
+ SET_BCH_SB_ENCRYPTION_TYPE(c->disk_sb.sb, 1);
+ bch2_write_super(c);
+err:
+ mutex_unlock(&c->sb_lock);
+ memzero_explicit(&user_key, sizeof(user_key));
+ memzero_explicit(&key, sizeof(key));
+ return ret;
+}
+
+void bch2_fs_encryption_exit(struct bch_fs *c)
+{
+ if (!IS_ERR_OR_NULL(c->poly1305))
+ crypto_free_shash(c->poly1305);
+ if (!IS_ERR_OR_NULL(c->chacha20))
+ crypto_free_sync_skcipher(c->chacha20);
+ if (!IS_ERR_OR_NULL(c->sha256))
+ crypto_free_shash(c->sha256);
+}
+
+int bch2_fs_encryption_init(struct bch_fs *c)
+{
+ struct bch_sb_field_crypt *crypt;
+ struct bch_key key;
+ int ret = 0;
+
+ c->sha256 = crypto_alloc_shash("sha256", 0, 0);
+ ret = PTR_ERR_OR_ZERO(c->sha256);
+ if (ret) {
+ bch_err(c, "error requesting sha256 module: %s", bch2_err_str(ret));
+ goto out;
+ }
+
+ crypt = bch2_sb_field_get(c->disk_sb.sb, crypt);
+ if (!crypt)
+ goto out;
+
+ ret = bch2_alloc_ciphers(c);
+ if (ret)
+ goto out;
+
+ ret = bch2_decrypt_sb_key(c, crypt, &key);
+ if (ret)
+ goto out;
+
+ ret = crypto_skcipher_setkey(&c->chacha20->base,
+ (void *) &key.key, sizeof(key.key));
+ if (ret)
+ goto out;
+out:
+ memzero_explicit(&key, sizeof(key));
+ return ret;
+}
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-21 23:11:57 +0300