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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /net/ceph/crypto.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'net/ceph/crypto.c')
-rw-r--r--net/ceph/crypto.c361
1 files changed, 361 insertions, 0 deletions
diff --git a/net/ceph/crypto.c b/net/ceph/crypto.c
new file mode 100644
index 000000000..051d22c0e
--- /dev/null
+++ b/net/ceph/crypto.c
@@ -0,0 +1,361 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/ceph/ceph_debug.h>
+
+#include <linux/err.h>
+#include <linux/scatterlist.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <crypto/aes.h>
+#include <crypto/skcipher.h>
+#include <linux/key-type.h>
+#include <linux/sched/mm.h>
+
+#include <keys/ceph-type.h>
+#include <keys/user-type.h>
+#include <linux/ceph/decode.h>
+#include "crypto.h"
+
+/*
+ * Set ->key and ->tfm. The rest of the key should be filled in before
+ * this function is called.
+ */
+static int set_secret(struct ceph_crypto_key *key, void *buf)
+{
+ unsigned int noio_flag;
+ int ret;
+
+ key->key = NULL;
+ key->tfm = NULL;
+
+ switch (key->type) {
+ case CEPH_CRYPTO_NONE:
+ return 0; /* nothing to do */
+ case CEPH_CRYPTO_AES:
+ break;
+ default:
+ return -ENOTSUPP;
+ }
+
+ if (!key->len)
+ return -EINVAL;
+
+ key->key = kmemdup(buf, key->len, GFP_NOIO);
+ if (!key->key) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ /* crypto_alloc_sync_skcipher() allocates with GFP_KERNEL */
+ noio_flag = memalloc_noio_save();
+ key->tfm = crypto_alloc_sync_skcipher("cbc(aes)", 0, 0);
+ memalloc_noio_restore(noio_flag);
+ if (IS_ERR(key->tfm)) {
+ ret = PTR_ERR(key->tfm);
+ key->tfm = NULL;
+ goto fail;
+ }
+
+ ret = crypto_sync_skcipher_setkey(key->tfm, key->key, key->len);
+ if (ret)
+ goto fail;
+
+ return 0;
+
+fail:
+ ceph_crypto_key_destroy(key);
+ return ret;
+}
+
+int ceph_crypto_key_clone(struct ceph_crypto_key *dst,
+ const struct ceph_crypto_key *src)
+{
+ memcpy(dst, src, sizeof(struct ceph_crypto_key));
+ return set_secret(dst, src->key);
+}
+
+int ceph_crypto_key_encode(struct ceph_crypto_key *key, void **p, void *end)
+{
+ if (*p + sizeof(u16) + sizeof(key->created) +
+ sizeof(u16) + key->len > end)
+ return -ERANGE;
+ ceph_encode_16(p, key->type);
+ ceph_encode_copy(p, &key->created, sizeof(key->created));
+ ceph_encode_16(p, key->len);
+ ceph_encode_copy(p, key->key, key->len);
+ return 0;
+}
+
+int ceph_crypto_key_decode(struct ceph_crypto_key *key, void **p, void *end)
+{
+ int ret;
+
+ ceph_decode_need(p, end, 2*sizeof(u16) + sizeof(key->created), bad);
+ key->type = ceph_decode_16(p);
+ ceph_decode_copy(p, &key->created, sizeof(key->created));
+ key->len = ceph_decode_16(p);
+ ceph_decode_need(p, end, key->len, bad);
+ ret = set_secret(key, *p);
+ memzero_explicit(*p, key->len);
+ *p += key->len;
+ return ret;
+
+bad:
+ dout("failed to decode crypto key\n");
+ return -EINVAL;
+}
+
+int ceph_crypto_key_unarmor(struct ceph_crypto_key *key, const char *inkey)
+{
+ int inlen = strlen(inkey);
+ int blen = inlen * 3 / 4;
+ void *buf, *p;
+ int ret;
+
+ dout("crypto_key_unarmor %s\n", inkey);
+ buf = kmalloc(blen, GFP_NOFS);
+ if (!buf)
+ return -ENOMEM;
+ blen = ceph_unarmor(buf, inkey, inkey+inlen);
+ if (blen < 0) {
+ kfree(buf);
+ return blen;
+ }
+
+ p = buf;
+ ret = ceph_crypto_key_decode(key, &p, p + blen);
+ kfree(buf);
+ if (ret)
+ return ret;
+ dout("crypto_key_unarmor key %p type %d len %d\n", key,
+ key->type, key->len);
+ return 0;
+}
+
+void ceph_crypto_key_destroy(struct ceph_crypto_key *key)
+{
+ if (key) {
+ kfree_sensitive(key->key);
+ key->key = NULL;
+ if (key->tfm) {
+ crypto_free_sync_skcipher(key->tfm);
+ key->tfm = NULL;
+ }
+ }
+}
+
+static const u8 *aes_iv = (u8 *)CEPH_AES_IV;
+
+/*
+ * Should be used for buffers allocated with kvmalloc().
+ * Currently these are encrypt out-buffer (ceph_buffer) and decrypt
+ * in-buffer (msg front).
+ *
+ * Dispose of @sgt with teardown_sgtable().
+ *
+ * @prealloc_sg is to avoid memory allocation inside sg_alloc_table()
+ * in cases where a single sg is sufficient. No attempt to reduce the
+ * number of sgs by squeezing physically contiguous pages together is
+ * made though, for simplicity.
+ */
+static int setup_sgtable(struct sg_table *sgt, struct scatterlist *prealloc_sg,
+ const void *buf, unsigned int buf_len)
+{
+ struct scatterlist *sg;
+ const bool is_vmalloc = is_vmalloc_addr(buf);
+ unsigned int off = offset_in_page(buf);
+ unsigned int chunk_cnt = 1;
+ unsigned int chunk_len = PAGE_ALIGN(off + buf_len);
+ int i;
+ int ret;
+
+ if (buf_len == 0) {
+ memset(sgt, 0, sizeof(*sgt));
+ return -EINVAL;
+ }
+
+ if (is_vmalloc) {
+ chunk_cnt = chunk_len >> PAGE_SHIFT;
+ chunk_len = PAGE_SIZE;
+ }
+
+ if (chunk_cnt > 1) {
+ ret = sg_alloc_table(sgt, chunk_cnt, GFP_NOFS);
+ if (ret)
+ return ret;
+ } else {
+ WARN_ON(chunk_cnt != 1);
+ sg_init_table(prealloc_sg, 1);
+ sgt->sgl = prealloc_sg;
+ sgt->nents = sgt->orig_nents = 1;
+ }
+
+ for_each_sg(sgt->sgl, sg, sgt->orig_nents, i) {
+ struct page *page;
+ unsigned int len = min(chunk_len - off, buf_len);
+
+ if (is_vmalloc)
+ page = vmalloc_to_page(buf);
+ else
+ page = virt_to_page(buf);
+
+ sg_set_page(sg, page, len, off);
+
+ off = 0;
+ buf += len;
+ buf_len -= len;
+ }
+ WARN_ON(buf_len != 0);
+
+ return 0;
+}
+
+static void teardown_sgtable(struct sg_table *sgt)
+{
+ if (sgt->orig_nents > 1)
+ sg_free_table(sgt);
+}
+
+static int ceph_aes_crypt(const struct ceph_crypto_key *key, bool encrypt,
+ void *buf, int buf_len, int in_len, int *pout_len)
+{
+ SYNC_SKCIPHER_REQUEST_ON_STACK(req, key->tfm);
+ struct sg_table sgt;
+ struct scatterlist prealloc_sg;
+ char iv[AES_BLOCK_SIZE] __aligned(8);
+ int pad_byte = AES_BLOCK_SIZE - (in_len & (AES_BLOCK_SIZE - 1));
+ int crypt_len = encrypt ? in_len + pad_byte : in_len;
+ int ret;
+
+ WARN_ON(crypt_len > buf_len);
+ if (encrypt)
+ memset(buf + in_len, pad_byte, pad_byte);
+ ret = setup_sgtable(&sgt, &prealloc_sg, buf, crypt_len);
+ if (ret)
+ return ret;
+
+ memcpy(iv, aes_iv, AES_BLOCK_SIZE);
+ skcipher_request_set_sync_tfm(req, key->tfm);
+ skcipher_request_set_callback(req, 0, NULL, NULL);
+ skcipher_request_set_crypt(req, sgt.sgl, sgt.sgl, crypt_len, iv);
+
+ /*
+ print_hex_dump(KERN_ERR, "key: ", DUMP_PREFIX_NONE, 16, 1,
+ key->key, key->len, 1);
+ print_hex_dump(KERN_ERR, " in: ", DUMP_PREFIX_NONE, 16, 1,
+ buf, crypt_len, 1);
+ */
+ if (encrypt)
+ ret = crypto_skcipher_encrypt(req);
+ else
+ ret = crypto_skcipher_decrypt(req);
+ skcipher_request_zero(req);
+ if (ret) {
+ pr_err("%s %scrypt failed: %d\n", __func__,
+ encrypt ? "en" : "de", ret);
+ goto out_sgt;
+ }
+ /*
+ print_hex_dump(KERN_ERR, "out: ", DUMP_PREFIX_NONE, 16, 1,
+ buf, crypt_len, 1);
+ */
+
+ if (encrypt) {
+ *pout_len = crypt_len;
+ } else {
+ pad_byte = *(char *)(buf + in_len - 1);
+ if (pad_byte > 0 && pad_byte <= AES_BLOCK_SIZE &&
+ in_len >= pad_byte) {
+ *pout_len = in_len - pad_byte;
+ } else {
+ pr_err("%s got bad padding %d on in_len %d\n",
+ __func__, pad_byte, in_len);
+ ret = -EPERM;
+ goto out_sgt;
+ }
+ }
+
+out_sgt:
+ teardown_sgtable(&sgt);
+ return ret;
+}
+
+int ceph_crypt(const struct ceph_crypto_key *key, bool encrypt,
+ void *buf, int buf_len, int in_len, int *pout_len)
+{
+ switch (key->type) {
+ case CEPH_CRYPTO_NONE:
+ *pout_len = in_len;
+ return 0;
+ case CEPH_CRYPTO_AES:
+ return ceph_aes_crypt(key, encrypt, buf, buf_len, in_len,
+ pout_len);
+ default:
+ return -ENOTSUPP;
+ }
+}
+
+static int ceph_key_preparse(struct key_preparsed_payload *prep)
+{
+ struct ceph_crypto_key *ckey;
+ size_t datalen = prep->datalen;
+ int ret;
+ void *p;
+
+ ret = -EINVAL;
+ if (datalen <= 0 || datalen > 32767 || !prep->data)
+ goto err;
+
+ ret = -ENOMEM;
+ ckey = kmalloc(sizeof(*ckey), GFP_KERNEL);
+ if (!ckey)
+ goto err;
+
+ /* TODO ceph_crypto_key_decode should really take const input */
+ p = (void *)prep->data;
+ ret = ceph_crypto_key_decode(ckey, &p, (char*)prep->data+datalen);
+ if (ret < 0)
+ goto err_ckey;
+
+ prep->payload.data[0] = ckey;
+ prep->quotalen = datalen;
+ return 0;
+
+err_ckey:
+ kfree(ckey);
+err:
+ return ret;
+}
+
+static void ceph_key_free_preparse(struct key_preparsed_payload *prep)
+{
+ struct ceph_crypto_key *ckey = prep->payload.data[0];
+ ceph_crypto_key_destroy(ckey);
+ kfree(ckey);
+}
+
+static void ceph_key_destroy(struct key *key)
+{
+ struct ceph_crypto_key *ckey = key->payload.data[0];
+
+ ceph_crypto_key_destroy(ckey);
+ kfree(ckey);
+}
+
+struct key_type key_type_ceph = {
+ .name = "ceph",
+ .preparse = ceph_key_preparse,
+ .free_preparse = ceph_key_free_preparse,
+ .instantiate = generic_key_instantiate,
+ .destroy = ceph_key_destroy,
+};
+
+int __init ceph_crypto_init(void)
+{
+ return register_key_type(&key_type_ceph);
+}
+
+void ceph_crypto_shutdown(void)
+{
+ unregister_key_type(&key_type_ceph);
+}