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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /net/ceph/crypto.c | |
parent | Initial commit. (diff) | |
download | linux-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.c | 361 |
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); +} |