mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-27 12:45:16 +07:00
e9f6452e0e
This patch removes the unnecessary ivsize variabls as they always have the value of AES_BLOCK_SIZE. Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
591 lines
14 KiB
C
591 lines
14 KiB
C
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#include <linux/ceph/ceph_debug.h>
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#include <linux/err.h>
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#include <linux/scatterlist.h>
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#include <linux/slab.h>
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#include <crypto/aes.h>
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#include <crypto/skcipher.h>
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#include <linux/key-type.h>
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#include <keys/ceph-type.h>
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#include <keys/user-type.h>
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#include <linux/ceph/decode.h>
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#include "crypto.h"
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int ceph_crypto_key_clone(struct ceph_crypto_key *dst,
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const struct ceph_crypto_key *src)
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{
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memcpy(dst, src, sizeof(struct ceph_crypto_key));
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dst->key = kmemdup(src->key, src->len, GFP_NOFS);
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if (!dst->key)
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return -ENOMEM;
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return 0;
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}
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int ceph_crypto_key_encode(struct ceph_crypto_key *key, void **p, void *end)
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{
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if (*p + sizeof(u16) + sizeof(key->created) +
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sizeof(u16) + key->len > end)
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return -ERANGE;
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ceph_encode_16(p, key->type);
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ceph_encode_copy(p, &key->created, sizeof(key->created));
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ceph_encode_16(p, key->len);
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ceph_encode_copy(p, key->key, key->len);
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return 0;
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}
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int ceph_crypto_key_decode(struct ceph_crypto_key *key, void **p, void *end)
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{
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ceph_decode_need(p, end, 2*sizeof(u16) + sizeof(key->created), bad);
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key->type = ceph_decode_16(p);
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ceph_decode_copy(p, &key->created, sizeof(key->created));
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key->len = ceph_decode_16(p);
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ceph_decode_need(p, end, key->len, bad);
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key->key = kmalloc(key->len, GFP_NOFS);
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if (!key->key)
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return -ENOMEM;
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ceph_decode_copy(p, key->key, key->len);
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return 0;
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bad:
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dout("failed to decode crypto key\n");
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return -EINVAL;
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}
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int ceph_crypto_key_unarmor(struct ceph_crypto_key *key, const char *inkey)
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{
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int inlen = strlen(inkey);
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int blen = inlen * 3 / 4;
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void *buf, *p;
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int ret;
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dout("crypto_key_unarmor %s\n", inkey);
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buf = kmalloc(blen, GFP_NOFS);
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if (!buf)
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return -ENOMEM;
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blen = ceph_unarmor(buf, inkey, inkey+inlen);
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if (blen < 0) {
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kfree(buf);
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return blen;
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}
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p = buf;
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ret = ceph_crypto_key_decode(key, &p, p + blen);
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kfree(buf);
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if (ret)
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return ret;
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dout("crypto_key_unarmor key %p type %d len %d\n", key,
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key->type, key->len);
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return 0;
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}
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static struct crypto_skcipher *ceph_crypto_alloc_cipher(void)
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{
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return crypto_alloc_skcipher("cbc(aes)", 0, CRYPTO_ALG_ASYNC);
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}
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static const u8 *aes_iv = (u8 *)CEPH_AES_IV;
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/*
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* Should be used for buffers allocated with ceph_kvmalloc().
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* Currently these are encrypt out-buffer (ceph_buffer) and decrypt
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* in-buffer (msg front).
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*
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* Dispose of @sgt with teardown_sgtable().
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*
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* @prealloc_sg is to avoid memory allocation inside sg_alloc_table()
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* in cases where a single sg is sufficient. No attempt to reduce the
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* number of sgs by squeezing physically contiguous pages together is
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* made though, for simplicity.
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*/
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static int setup_sgtable(struct sg_table *sgt, struct scatterlist *prealloc_sg,
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const void *buf, unsigned int buf_len)
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{
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struct scatterlist *sg;
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const bool is_vmalloc = is_vmalloc_addr(buf);
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unsigned int off = offset_in_page(buf);
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unsigned int chunk_cnt = 1;
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unsigned int chunk_len = PAGE_ALIGN(off + buf_len);
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int i;
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int ret;
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if (buf_len == 0) {
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memset(sgt, 0, sizeof(*sgt));
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return -EINVAL;
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}
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if (is_vmalloc) {
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chunk_cnt = chunk_len >> PAGE_SHIFT;
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chunk_len = PAGE_SIZE;
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}
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if (chunk_cnt > 1) {
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ret = sg_alloc_table(sgt, chunk_cnt, GFP_NOFS);
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if (ret)
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return ret;
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} else {
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WARN_ON(chunk_cnt != 1);
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sg_init_table(prealloc_sg, 1);
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sgt->sgl = prealloc_sg;
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sgt->nents = sgt->orig_nents = 1;
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}
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for_each_sg(sgt->sgl, sg, sgt->orig_nents, i) {
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struct page *page;
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unsigned int len = min(chunk_len - off, buf_len);
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if (is_vmalloc)
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page = vmalloc_to_page(buf);
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else
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page = virt_to_page(buf);
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sg_set_page(sg, page, len, off);
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off = 0;
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buf += len;
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buf_len -= len;
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}
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WARN_ON(buf_len != 0);
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return 0;
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}
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static void teardown_sgtable(struct sg_table *sgt)
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{
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if (sgt->orig_nents > 1)
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sg_free_table(sgt);
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}
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static int ceph_aes_encrypt(const void *key, int key_len,
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void *dst, size_t *dst_len,
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const void *src, size_t src_len)
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{
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struct scatterlist sg_in[2], prealloc_sg;
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struct sg_table sg_out;
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struct crypto_skcipher *tfm = ceph_crypto_alloc_cipher();
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SKCIPHER_REQUEST_ON_STACK(req, tfm);
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int ret;
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char iv[AES_BLOCK_SIZE];
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size_t zero_padding = (0x10 - (src_len & 0x0f));
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char pad[16];
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if (IS_ERR(tfm))
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return PTR_ERR(tfm);
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memset(pad, zero_padding, zero_padding);
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*dst_len = src_len + zero_padding;
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sg_init_table(sg_in, 2);
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sg_set_buf(&sg_in[0], src, src_len);
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sg_set_buf(&sg_in[1], pad, zero_padding);
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ret = setup_sgtable(&sg_out, &prealloc_sg, dst, *dst_len);
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if (ret)
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goto out_tfm;
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crypto_skcipher_setkey((void *)tfm, key, key_len);
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memcpy(iv, aes_iv, AES_BLOCK_SIZE);
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skcipher_request_set_tfm(req, tfm);
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skcipher_request_set_callback(req, 0, NULL, NULL);
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skcipher_request_set_crypt(req, sg_in, sg_out.sgl,
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src_len + zero_padding, iv);
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/*
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print_hex_dump(KERN_ERR, "enc key: ", DUMP_PREFIX_NONE, 16, 1,
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key, key_len, 1);
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print_hex_dump(KERN_ERR, "enc src: ", DUMP_PREFIX_NONE, 16, 1,
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src, src_len, 1);
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print_hex_dump(KERN_ERR, "enc pad: ", DUMP_PREFIX_NONE, 16, 1,
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pad, zero_padding, 1);
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*/
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ret = crypto_skcipher_encrypt(req);
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skcipher_request_zero(req);
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if (ret < 0) {
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pr_err("ceph_aes_crypt failed %d\n", ret);
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goto out_sg;
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}
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/*
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print_hex_dump(KERN_ERR, "enc out: ", DUMP_PREFIX_NONE, 16, 1,
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dst, *dst_len, 1);
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*/
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out_sg:
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teardown_sgtable(&sg_out);
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out_tfm:
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crypto_free_skcipher(tfm);
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return ret;
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}
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static int ceph_aes_encrypt2(const void *key, int key_len, void *dst,
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size_t *dst_len,
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const void *src1, size_t src1_len,
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const void *src2, size_t src2_len)
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{
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struct scatterlist sg_in[3], prealloc_sg;
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struct sg_table sg_out;
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struct crypto_skcipher *tfm = ceph_crypto_alloc_cipher();
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SKCIPHER_REQUEST_ON_STACK(req, tfm);
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int ret;
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char iv[AES_BLOCK_SIZE];
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size_t zero_padding = (0x10 - ((src1_len + src2_len) & 0x0f));
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char pad[16];
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if (IS_ERR(tfm))
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return PTR_ERR(tfm);
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memset(pad, zero_padding, zero_padding);
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*dst_len = src1_len + src2_len + zero_padding;
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sg_init_table(sg_in, 3);
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sg_set_buf(&sg_in[0], src1, src1_len);
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sg_set_buf(&sg_in[1], src2, src2_len);
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sg_set_buf(&sg_in[2], pad, zero_padding);
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ret = setup_sgtable(&sg_out, &prealloc_sg, dst, *dst_len);
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if (ret)
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goto out_tfm;
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crypto_skcipher_setkey((void *)tfm, key, key_len);
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memcpy(iv, aes_iv, AES_BLOCK_SIZE);
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skcipher_request_set_tfm(req, tfm);
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skcipher_request_set_callback(req, 0, NULL, NULL);
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skcipher_request_set_crypt(req, sg_in, sg_out.sgl,
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src1_len + src2_len + zero_padding, iv);
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/*
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print_hex_dump(KERN_ERR, "enc key: ", DUMP_PREFIX_NONE, 16, 1,
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key, key_len, 1);
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print_hex_dump(KERN_ERR, "enc src1: ", DUMP_PREFIX_NONE, 16, 1,
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src1, src1_len, 1);
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print_hex_dump(KERN_ERR, "enc src2: ", DUMP_PREFIX_NONE, 16, 1,
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src2, src2_len, 1);
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print_hex_dump(KERN_ERR, "enc pad: ", DUMP_PREFIX_NONE, 16, 1,
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pad, zero_padding, 1);
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*/
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ret = crypto_skcipher_encrypt(req);
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skcipher_request_zero(req);
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if (ret < 0) {
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pr_err("ceph_aes_crypt2 failed %d\n", ret);
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goto out_sg;
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}
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/*
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print_hex_dump(KERN_ERR, "enc out: ", DUMP_PREFIX_NONE, 16, 1,
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dst, *dst_len, 1);
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*/
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out_sg:
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teardown_sgtable(&sg_out);
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out_tfm:
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crypto_free_skcipher(tfm);
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return ret;
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}
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static int ceph_aes_decrypt(const void *key, int key_len,
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void *dst, size_t *dst_len,
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const void *src, size_t src_len)
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{
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struct sg_table sg_in;
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struct scatterlist sg_out[2], prealloc_sg;
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struct crypto_skcipher *tfm = ceph_crypto_alloc_cipher();
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SKCIPHER_REQUEST_ON_STACK(req, tfm);
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char pad[16];
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char iv[AES_BLOCK_SIZE];
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int ret;
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int last_byte;
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if (IS_ERR(tfm))
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return PTR_ERR(tfm);
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sg_init_table(sg_out, 2);
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sg_set_buf(&sg_out[0], dst, *dst_len);
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sg_set_buf(&sg_out[1], pad, sizeof(pad));
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ret = setup_sgtable(&sg_in, &prealloc_sg, src, src_len);
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if (ret)
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goto out_tfm;
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crypto_skcipher_setkey((void *)tfm, key, key_len);
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memcpy(iv, aes_iv, AES_BLOCK_SIZE);
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skcipher_request_set_tfm(req, tfm);
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skcipher_request_set_callback(req, 0, NULL, NULL);
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skcipher_request_set_crypt(req, sg_in.sgl, sg_out,
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src_len, iv);
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/*
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print_hex_dump(KERN_ERR, "dec key: ", DUMP_PREFIX_NONE, 16, 1,
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key, key_len, 1);
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print_hex_dump(KERN_ERR, "dec in: ", DUMP_PREFIX_NONE, 16, 1,
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src, src_len, 1);
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*/
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ret = crypto_skcipher_decrypt(req);
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skcipher_request_zero(req);
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if (ret < 0) {
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pr_err("ceph_aes_decrypt failed %d\n", ret);
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goto out_sg;
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}
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if (src_len <= *dst_len)
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last_byte = ((char *)dst)[src_len - 1];
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else
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last_byte = pad[src_len - *dst_len - 1];
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if (last_byte <= 16 && src_len >= last_byte) {
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*dst_len = src_len - last_byte;
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} else {
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pr_err("ceph_aes_decrypt got bad padding %d on src len %d\n",
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last_byte, (int)src_len);
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return -EPERM; /* bad padding */
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}
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/*
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print_hex_dump(KERN_ERR, "dec out: ", DUMP_PREFIX_NONE, 16, 1,
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dst, *dst_len, 1);
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*/
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out_sg:
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teardown_sgtable(&sg_in);
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out_tfm:
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crypto_free_skcipher(tfm);
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return ret;
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}
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static int ceph_aes_decrypt2(const void *key, int key_len,
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void *dst1, size_t *dst1_len,
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void *dst2, size_t *dst2_len,
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const void *src, size_t src_len)
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{
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struct sg_table sg_in;
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struct scatterlist sg_out[3], prealloc_sg;
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struct crypto_skcipher *tfm = ceph_crypto_alloc_cipher();
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SKCIPHER_REQUEST_ON_STACK(req, tfm);
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char pad[16];
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char iv[AES_BLOCK_SIZE];
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int ret;
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int last_byte;
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if (IS_ERR(tfm))
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return PTR_ERR(tfm);
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sg_init_table(sg_out, 3);
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sg_set_buf(&sg_out[0], dst1, *dst1_len);
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sg_set_buf(&sg_out[1], dst2, *dst2_len);
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sg_set_buf(&sg_out[2], pad, sizeof(pad));
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ret = setup_sgtable(&sg_in, &prealloc_sg, src, src_len);
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if (ret)
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goto out_tfm;
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crypto_skcipher_setkey((void *)tfm, key, key_len);
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memcpy(iv, aes_iv, AES_BLOCK_SIZE);
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skcipher_request_set_tfm(req, tfm);
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skcipher_request_set_callback(req, 0, NULL, NULL);
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skcipher_request_set_crypt(req, sg_in.sgl, sg_out,
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src_len, iv);
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/*
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print_hex_dump(KERN_ERR, "dec key: ", DUMP_PREFIX_NONE, 16, 1,
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key, key_len, 1);
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print_hex_dump(KERN_ERR, "dec in: ", DUMP_PREFIX_NONE, 16, 1,
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src, src_len, 1);
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*/
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ret = crypto_skcipher_decrypt(req);
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skcipher_request_zero(req);
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if (ret < 0) {
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pr_err("ceph_aes_decrypt failed %d\n", ret);
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goto out_sg;
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}
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if (src_len <= *dst1_len)
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last_byte = ((char *)dst1)[src_len - 1];
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else if (src_len <= *dst1_len + *dst2_len)
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last_byte = ((char *)dst2)[src_len - *dst1_len - 1];
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else
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last_byte = pad[src_len - *dst1_len - *dst2_len - 1];
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if (last_byte <= 16 && src_len >= last_byte) {
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src_len -= last_byte;
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} else {
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pr_err("ceph_aes_decrypt got bad padding %d on src len %d\n",
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last_byte, (int)src_len);
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return -EPERM; /* bad padding */
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}
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if (src_len < *dst1_len) {
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*dst1_len = src_len;
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*dst2_len = 0;
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} else {
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*dst2_len = src_len - *dst1_len;
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}
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/*
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print_hex_dump(KERN_ERR, "dec out1: ", DUMP_PREFIX_NONE, 16, 1,
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dst1, *dst1_len, 1);
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print_hex_dump(KERN_ERR, "dec out2: ", DUMP_PREFIX_NONE, 16, 1,
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dst2, *dst2_len, 1);
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*/
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out_sg:
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teardown_sgtable(&sg_in);
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out_tfm:
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crypto_free_skcipher(tfm);
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return ret;
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}
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int ceph_decrypt(struct ceph_crypto_key *secret, void *dst, size_t *dst_len,
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const void *src, size_t src_len)
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{
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switch (secret->type) {
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case CEPH_CRYPTO_NONE:
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if (*dst_len < src_len)
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return -ERANGE;
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memcpy(dst, src, src_len);
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*dst_len = src_len;
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return 0;
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case CEPH_CRYPTO_AES:
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return ceph_aes_decrypt(secret->key, secret->len, dst,
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dst_len, src, src_len);
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default:
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return -EINVAL;
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}
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}
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int ceph_decrypt2(struct ceph_crypto_key *secret,
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void *dst1, size_t *dst1_len,
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void *dst2, size_t *dst2_len,
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const void *src, size_t src_len)
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{
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size_t t;
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switch (secret->type) {
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case CEPH_CRYPTO_NONE:
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if (*dst1_len + *dst2_len < src_len)
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return -ERANGE;
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t = min(*dst1_len, src_len);
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memcpy(dst1, src, t);
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*dst1_len = t;
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src += t;
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src_len -= t;
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if (src_len) {
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t = min(*dst2_len, src_len);
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memcpy(dst2, src, t);
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*dst2_len = t;
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}
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return 0;
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|
|
|
case CEPH_CRYPTO_AES:
|
|
return ceph_aes_decrypt2(secret->key, secret->len,
|
|
dst1, dst1_len, dst2, dst2_len,
|
|
src, src_len);
|
|
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
int ceph_encrypt(struct ceph_crypto_key *secret, void *dst, size_t *dst_len,
|
|
const void *src, size_t src_len)
|
|
{
|
|
switch (secret->type) {
|
|
case CEPH_CRYPTO_NONE:
|
|
if (*dst_len < src_len)
|
|
return -ERANGE;
|
|
memcpy(dst, src, src_len);
|
|
*dst_len = src_len;
|
|
return 0;
|
|
|
|
case CEPH_CRYPTO_AES:
|
|
return ceph_aes_encrypt(secret->key, secret->len, dst,
|
|
dst_len, src, src_len);
|
|
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
int ceph_encrypt2(struct ceph_crypto_key *secret, void *dst, size_t *dst_len,
|
|
const void *src1, size_t src1_len,
|
|
const void *src2, size_t src2_len)
|
|
{
|
|
switch (secret->type) {
|
|
case CEPH_CRYPTO_NONE:
|
|
if (*dst_len < src1_len + src2_len)
|
|
return -ERANGE;
|
|
memcpy(dst, src1, src1_len);
|
|
memcpy(dst + src1_len, src2, src2_len);
|
|
*dst_len = src1_len + src2_len;
|
|
return 0;
|
|
|
|
case CEPH_CRYPTO_AES:
|
|
return ceph_aes_encrypt2(secret->key, secret->len, dst, dst_len,
|
|
src1, src1_len, src2, src2_len);
|
|
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
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 ceph_crypto_init(void) {
|
|
return register_key_type(&key_type_ceph);
|
|
}
|
|
|
|
void ceph_crypto_shutdown(void) {
|
|
unregister_key_type(&key_type_ceph);
|
|
}
|