[mirror_ubuntu-bionic-kernel.git] / net / ceph / crypto.c


#include <linux/ceph/ceph_debug.h>

#include <linux/err.h>
#include <linux/scatterlist.h>
#include <linux/slab.h>
#include <crypto/aes.h>
#include <crypto/skcipher.h>
#include <linux/key-type.h>

#include <keys/ceph-type.h>
#include <keys/user-type.h>
#include <linux/ceph/decode.h>
#include "crypto.h"

int ceph_crypto_key_clone(struct ceph_crypto_key *dst,
			  const struct ceph_crypto_key *src)
{
	memcpy(dst, src, sizeof(struct ceph_crypto_key));
	dst->key = kmemdup(src->key, src->len, GFP_NOFS);
	if (!dst->key)
		return -ENOMEM;
	return 0;
}

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)
{
	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);
	key->key = kmalloc(key->len, GFP_NOFS);
	if (!key->key)
		return -ENOMEM;
	ceph_decode_copy(p, key->key, key->len);
	return 0;

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;
}

static struct crypto_skcipher *ceph_crypto_alloc_cipher(void)
{
	return crypto_alloc_skcipher("cbc(aes)", 0, CRYPTO_ALG_ASYNC);
}

static const u8 *aes_iv = (u8 *)CEPH_AES_IV;

/*
 * Should be used for buffers allocated with ceph_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_encrypt(const void *key, int key_len,
			    void *dst, size_t *dst_len,
			    const void *src, size_t src_len)
{
	struct scatterlist sg_in[2], prealloc_sg;
	struct sg_table sg_out;
	struct crypto_skcipher *tfm = ceph_crypto_alloc_cipher();
	SKCIPHER_REQUEST_ON_STACK(req, tfm);
	int ret;
	char iv[AES_BLOCK_SIZE];
	size_t zero_padding = (0x10 - (src_len & 0x0f));
	char pad[16];

	if (IS_ERR(tfm))
		return PTR_ERR(tfm);

	memset(pad, zero_padding, zero_padding);

	*dst_len = src_len + zero_padding;

	sg_init_table(sg_in, 2);
	sg_set_buf(&sg_in[0], src, src_len);
	sg_set_buf(&sg_in[1], pad, zero_padding);
	ret = setup_sgtable(&sg_out, &prealloc_sg, dst, *dst_len);
	if (ret)
		goto out_tfm;

	crypto_skcipher_setkey((void *)tfm, key, key_len);
	memcpy(iv, aes_iv, AES_BLOCK_SIZE);

	skcipher_request_set_tfm(req, tfm);
	skcipher_request_set_callback(req, 0, NULL, NULL);
	skcipher_request_set_crypt(req, sg_in, sg_out.sgl,
				   src_len + zero_padding, iv);

	/*
	print_hex_dump(KERN_ERR, "enc key: ", DUMP_PREFIX_NONE, 16, 1,
		       key, key_len, 1);
	print_hex_dump(KERN_ERR, "enc src: ", DUMP_PREFIX_NONE, 16, 1,
			src, src_len, 1);
	print_hex_dump(KERN_ERR, "enc pad: ", DUMP_PREFIX_NONE, 16, 1,
			pad, zero_padding, 1);
	*/
	ret = crypto_skcipher_encrypt(req);
	skcipher_request_zero(req);
	if (ret < 0) {
		pr_err("ceph_aes_crypt failed %d\n", ret);
		goto out_sg;
	}
	/*
	print_hex_dump(KERN_ERR, "enc out: ", DUMP_PREFIX_NONE, 16, 1,
		       dst, *dst_len, 1);
	*/

out_sg:
	teardown_sgtable(&sg_out);
out_tfm:
	crypto_free_skcipher(tfm);
	return ret;
}

static int ceph_aes_encrypt2(const void *key, int key_len, void *dst,
			     size_t *dst_len,
			     const void *src1, size_t src1_len,
			     const void *src2, size_t src2_len)
{
	struct scatterlist sg_in[3], prealloc_sg;
	struct sg_table sg_out;
	struct crypto_skcipher *tfm = ceph_crypto_alloc_cipher();
	SKCIPHER_REQUEST_ON_STACK(req, tfm);
	int ret;
	char iv[AES_BLOCK_SIZE];
	size_t zero_padding = (0x10 - ((src1_len + src2_len) & 0x0f));
	char pad[16];

	if (IS_ERR(tfm))
		return PTR_ERR(tfm);

	memset(pad, zero_padding, zero_padding);

	*dst_len = src1_len + src2_len + zero_padding;

	sg_init_table(sg_in, 3);
	sg_set_buf(&sg_in[0], src1, src1_len);
	sg_set_buf(&sg_in[1], src2, src2_len);
	sg_set_buf(&sg_in[2], pad, zero_padding);
	ret = setup_sgtable(&sg_out, &prealloc_sg, dst, *dst_len);
	if (ret)
		goto out_tfm;

	crypto_skcipher_setkey((void *)tfm, key, key_len);
	memcpy(iv, aes_iv, AES_BLOCK_SIZE);

	skcipher_request_set_tfm(req, tfm);
	skcipher_request_set_callback(req, 0, NULL, NULL);
	skcipher_request_set_crypt(req, sg_in, sg_out.sgl,
				   src1_len + src2_len + zero_padding, iv);

	/*
	print_hex_dump(KERN_ERR, "enc  key: ", DUMP_PREFIX_NONE, 16, 1,
		       key, key_len, 1);
	print_hex_dump(KERN_ERR, "enc src1: ", DUMP_PREFIX_NONE, 16, 1,
			src1, src1_len, 1);
	print_hex_dump(KERN_ERR, "enc src2: ", DUMP_PREFIX_NONE, 16, 1,
			src2, src2_len, 1);
	print_hex_dump(KERN_ERR, "enc  pad: ", DUMP_PREFIX_NONE, 16, 1,
			pad, zero_padding, 1);
	*/
	ret = crypto_skcipher_encrypt(req);
	skcipher_request_zero(req);
	if (ret < 0) {
		pr_err("ceph_aes_crypt2 failed %d\n", ret);
		goto out_sg;
	}
	/*
	print_hex_dump(KERN_ERR, "enc  out: ", DUMP_PREFIX_NONE, 16, 1,
		       dst, *dst_len, 1);
	*/

out_sg:
	teardown_sgtable(&sg_out);
out_tfm:
	crypto_free_skcipher(tfm);
	return ret;
}

static int ceph_aes_decrypt(const void *key, int key_len,
			    void *dst, size_t *dst_len,
			    const void *src, size_t src_len)
{
	struct sg_table sg_in;
	struct scatterlist sg_out[2], prealloc_sg;
	struct crypto_skcipher *tfm = ceph_crypto_alloc_cipher();
	SKCIPHER_REQUEST_ON_STACK(req, tfm);
	char pad[16];
	char iv[AES_BLOCK_SIZE];
	int ret;
	int last_byte;

	if (IS_ERR(tfm))
		return PTR_ERR(tfm);

	sg_init_table(sg_out, 2);
	sg_set_buf(&sg_out[0], dst, *dst_len);
	sg_set_buf(&sg_out[1], pad, sizeof(pad));
	ret = setup_sgtable(&sg_in, &prealloc_sg, src, src_len);
	if (ret)
		goto out_tfm;

	crypto_skcipher_setkey((void *)tfm, key, key_len);
	memcpy(iv, aes_iv, AES_BLOCK_SIZE);

	skcipher_request_set_tfm(req, tfm);
	skcipher_request_set_callback(req, 0, NULL, NULL);
	skcipher_request_set_crypt(req, sg_in.sgl, sg_out,
				   src_len, iv);

	/*
	print_hex_dump(KERN_ERR, "dec key: ", DUMP_PREFIX_NONE, 16, 1,
		       key, key_len, 1);
	print_hex_dump(KERN_ERR, "dec  in: ", DUMP_PREFIX_NONE, 16, 1,
		       src, src_len, 1);
	*/
	ret = crypto_skcipher_decrypt(req);
	skcipher_request_zero(req);
	if (ret < 0) {
		pr_err("ceph_aes_decrypt failed %d\n", ret);
		goto out_sg;
	}

	if (src_len <= *dst_len)
		last_byte = ((char *)dst)[src_len - 1];
	else
		last_byte = pad[src_len - *dst_len - 1];
	if (last_byte <= 16 && src_len >= last_byte) {
		*dst_len = src_len - last_byte;
	} else {
		pr_err("ceph_aes_decrypt got bad padding %d on src len %d\n",
		       last_byte, (int)src_len);
		return -EPERM;  /* bad padding */
	}
	/*
	print_hex_dump(KERN_ERR, "dec out: ", DUMP_PREFIX_NONE, 16, 1,
		       dst, *dst_len, 1);
	*/

out_sg:
	teardown_sgtable(&sg_in);
out_tfm:
	crypto_free_skcipher(tfm);
	return ret;
}

static int ceph_aes_decrypt2(const void *key, int key_len,
			     void *dst1, size_t *dst1_len,
			     void *dst2, size_t *dst2_len,
			     const void *src, size_t src_len)
{
	struct sg_table sg_in;
	struct scatterlist sg_out[3], prealloc_sg;
	struct crypto_skcipher *tfm = ceph_crypto_alloc_cipher();
	SKCIPHER_REQUEST_ON_STACK(req, tfm);
	char pad[16];
	char iv[AES_BLOCK_SIZE];
	int ret;
	int last_byte;

	if (IS_ERR(tfm))
		return PTR_ERR(tfm);

	sg_init_table(sg_out, 3);
	sg_set_buf(&sg_out[0], dst1, *dst1_len);
	sg_set_buf(&sg_out[1], dst2, *dst2_len);
	sg_set_buf(&sg_out[2], pad, sizeof(pad));
	ret = setup_sgtable(&sg_in, &prealloc_sg, src, src_len);
	if (ret)
		goto out_tfm;

	crypto_skcipher_setkey((void *)tfm, key, key_len);
	memcpy(iv, aes_iv, AES_BLOCK_SIZE);

	skcipher_request_set_tfm(req, tfm);
	skcipher_request_set_callback(req, 0, NULL, NULL);
	skcipher_request_set_crypt(req, sg_in.sgl, sg_out,
				   src_len, iv);

	/*
	print_hex_dump(KERN_ERR, "dec  key: ", DUMP_PREFIX_NONE, 16, 1,
		       key, key_len, 1);
	print_hex_dump(KERN_ERR, "dec   in: ", DUMP_PREFIX_NONE, 16, 1,
		       src, src_len, 1);
	*/
	ret = crypto_skcipher_decrypt(req);
	skcipher_request_zero(req);
	if (ret < 0) {
		pr_err("ceph_aes_decrypt failed %d\n", ret);
		goto out_sg;
	}

	if (src_len <= *dst1_len)
		last_byte = ((char *)dst1)[src_len - 1];
	else if (src_len <= *dst1_len + *dst2_len)
		last_byte = ((char *)dst2)[src_len - *dst1_len - 1];
	else
		last_byte = pad[src_len - *dst1_len - *dst2_len - 1];
	if (last_byte <= 16 && src_len >= last_byte) {
		src_len -= last_byte;
	} else {
		pr_err("ceph_aes_decrypt got bad padding %d on src len %d\n",
		       last_byte, (int)src_len);
		return -EPERM;  /* bad padding */
	}

	if (src_len < *dst1_len) {
		*dst1_len = src_len;
		*dst2_len = 0;
	} else {
		*dst2_len = src_len - *dst1_len;
	}
	/*
	print_hex_dump(KERN_ERR, "dec  out1: ", DUMP_PREFIX_NONE, 16, 1,
		       dst1, *dst1_len, 1);
	print_hex_dump(KERN_ERR, "dec  out2: ", DUMP_PREFIX_NONE, 16, 1,
		       dst2, *dst2_len, 1);
	*/

out_sg:
	teardown_sgtable(&sg_in);
out_tfm:
	crypto_free_skcipher(tfm);
	return ret;
}


int ceph_decrypt(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_decrypt(secret->key, secret->len, dst,
					dst_len, src, src_len);

	default:
		return -EINVAL;
	}
}

int ceph_decrypt2(struct ceph_crypto_key *secret,
			void *dst1, size_t *dst1_len,
			void *dst2, size_t *dst2_len,
			const void *src, size_t src_len)
{
	size_t t;

	switch (secret->type) {
	case CEPH_CRYPTO_NONE:
		if (*dst1_len + *dst2_len < src_len)
			return -ERANGE;
		t = min(*dst1_len, src_len);
		memcpy(dst1, src, t);
		*dst1_len = t;
		src += t;
		src_len -= t;
		if (src_len) {
			t = min(*dst2_len, src_len);
			memcpy(dst2, src, t);
			*dst2_len = t;
		}
		return 0;

	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);
}
Commit	Line	Data
8b6e4f2d	1
3d14c5d2	2	#include <linux/ceph/ceph_debug.h>
8b6e4f2d SW	3
	4	#include <linux/err.h>
	5	#include <linux/scatterlist.h>
5a0e3ad6	6	#include <linux/slab.h>
e59dd982 HX	7	#include <crypto/aes.h>
e59dd982 HX	8	#include <crypto/skcipher.h>
4b2a58ab	9	#include <linux/key-type.h>
8b6e4f2d	10
4b2a58ab	11	#include <keys/ceph-type.h>
7c3bec0a	12	#include <keys/user-type.h>
3d14c5d2	13	#include <linux/ceph/decode.h>
8b6e4f2d	14	#include "crypto.h"
8b6e4f2d	15
8323c3aa TV	16	int ceph_crypto_key_clone(struct ceph_crypto_key *dst,
	17	const struct ceph_crypto_key *src)
	18	{
	19	memcpy(dst, src, sizeof(struct ceph_crypto_key));
18648256	20	dst->key = kmemdup(src->key, src->len, GFP_NOFS);
8323c3aa TV	21	if (!dst->key)
8323c3aa TV	22	return -ENOMEM;
8323c3aa TV	23	return 0;
	24	}
	25
8b6e4f2d SW	26	int ceph_crypto_key_encode(struct ceph_crypto_key key, void p, void end)
	27	{
	28	if (*p + sizeof(u16) + sizeof(key->created) +
	29	sizeof(u16) + key->len > end)
	30	return -ERANGE;
	31	ceph_encode_16(p, key->type);
	32	ceph_encode_copy(p, &key->created, sizeof(key->created));
	33	ceph_encode_16(p, key->len);
	34	ceph_encode_copy(p, key->key, key->len);
	35	return 0;
	36	}
	37
	38	int ceph_crypto_key_decode(struct ceph_crypto_key key, void p, void end)
	39	{
	40	ceph_decode_need(p, end, 2*sizeof(u16) + sizeof(key->created), bad);
	41	key->type = ceph_decode_16(p);
	42	ceph_decode_copy(p, &key->created, sizeof(key->created));
	43	key->len = ceph_decode_16(p);
	44	ceph_decode_need(p, end, key->len, bad);
	45	key->key = kmalloc(key->len, GFP_NOFS);
	46	if (!key->key)
	47	return -ENOMEM;
	48	ceph_decode_copy(p, key->key, key->len);
	49	return 0;
	50
	51	bad:
	52	dout("failed to decode crypto key\n");
	53	return -EINVAL;
	54	}
	55
	56	int ceph_crypto_key_unarmor(struct ceph_crypto_key key, const char inkey)
	57	{
	58	int inlen = strlen(inkey);
	59	int blen = inlen * 3 / 4;
	60	void buf, p;
	61	int ret;
	62
	63	dout("crypto_key_unarmor %s\n", inkey);
	64	buf = kmalloc(blen, GFP_NOFS);
	65	if (!buf)
	66	return -ENOMEM;
	67	blen = ceph_unarmor(buf, inkey, inkey+inlen);
	68	if (blen < 0) {
	69	kfree(buf);
	70	return blen;
	71	}
	72
	73	p = buf;
	74	ret = ceph_crypto_key_decode(key, &p, p + blen);
	75	kfree(buf);
	76	if (ret)
	77	return ret;
	78	dout("crypto_key_unarmor key %p type %d len %d\n", key,
	79	key->type, key->len);
	80	return 0;
	81	}
	82
e59dd982	83	static struct crypto_skcipher *ceph_crypto_alloc_cipher(void)
8b6e4f2d	84	{
e59dd982	85	return crypto_alloc_skcipher("cbc(aes)", 0, CRYPTO_ALG_ASYNC);
8b6e4f2d SW	86	}
8b6e4f2d SW	87
cbbfe499	88	static const u8 aes_iv = (u8 )CEPH_AES_IV;
8b6e4f2d	89
aaef3170 ID	90	/*
	91	* Should be used for buffers allocated with ceph_kvmalloc().
	92	* Currently these are encrypt out-buffer (ceph_buffer) and decrypt
	93	* in-buffer (msg front).
	94	*
	95	* Dispose of @sgt with teardown_sgtable().
	96	*
	97	* @prealloc_sg is to avoid memory allocation inside sg_alloc_table()
	98	* in cases where a single sg is sufficient. No attempt to reduce the
	99	* number of sgs by squeezing physically contiguous pages together is
	100	* made though, for simplicity.
	101	*/
	102	static int setup_sgtable(struct sg_table sgt, struct scatterlist prealloc_sg,
	103	const void *buf, unsigned int buf_len)
	104	{
	105	struct scatterlist *sg;
	106	const bool is_vmalloc = is_vmalloc_addr(buf);
	107	unsigned int off = offset_in_page(buf);
	108	unsigned int chunk_cnt = 1;
	109	unsigned int chunk_len = PAGE_ALIGN(off + buf_len);
	110	int i;
	111	int ret;
	112
	113	if (buf_len == 0) {
	114	memset(sgt, 0, sizeof(*sgt));
	115	return -EINVAL;
	116	}
	117
	118	if (is_vmalloc) {
	119	chunk_cnt = chunk_len >> PAGE_SHIFT;
	120	chunk_len = PAGE_SIZE;
	121	}
	122
	123	if (chunk_cnt > 1) {
	124	ret = sg_alloc_table(sgt, chunk_cnt, GFP_NOFS);
	125	if (ret)
	126	return ret;
	127	} else {
	128	WARN_ON(chunk_cnt != 1);
	129	sg_init_table(prealloc_sg, 1);
	130	sgt->sgl = prealloc_sg;
	131	sgt->nents = sgt->orig_nents = 1;
	132	}
	133
	134	for_each_sg(sgt->sgl, sg, sgt->orig_nents, i) {
	135	struct page *page;
	136	unsigned int len = min(chunk_len - off, buf_len);
	137
	138	if (is_vmalloc)
	139	page = vmalloc_to_page(buf);
	140	else
	141	page = virt_to_page(buf);
	142
	143	sg_set_page(sg, page, len, off);
	144
	145	off = 0;
	146	buf += len;
	147	buf_len -= len;
	148	}
	149	WARN_ON(buf_len != 0);
	150
	151	return 0;
	152	}
	153
154	static void teardown_sgtable(struct sg_table *sgt)
155	{
156	if (sgt->orig_nents > 1)
157	sg_free_table(sgt);
158	}
159
cd84db6e YS	160	static int ceph_aes_encrypt(const void *key, int key_len,
	161	void dst, size_t dst_len,
	162	const void *src, size_t src_len)
8b6e4f2d	163	{
aaef3170 ID	164	struct scatterlist sg_in[2], prealloc_sg;
aaef3170 ID	165	struct sg_table sg_out;
e59dd982 HX	166	struct crypto_skcipher *tfm = ceph_crypto_alloc_cipher();
e59dd982 HX	167	SKCIPHER_REQUEST_ON_STACK(req, tfm);
8b6e4f2d	168	int ret;
e9f6452e	169	char iv[AES_BLOCK_SIZE];
8b6e4f2d SW	170	size_t zero_padding = (0x10 - (src_len & 0x0f));
	171	char pad[16];
	172
	173	if (IS_ERR(tfm))
	174	return PTR_ERR(tfm);
	175
	176	memset(pad, zero_padding, zero_padding);
	177
	178	*dst_len = src_len + zero_padding;
	179
8b6e4f2d SW	180	sg_init_table(sg_in, 2);
	181	sg_set_buf(&sg_in[0], src, src_len);
	182	sg_set_buf(&sg_in[1], pad, zero_padding);
aaef3170 ID	183	ret = setup_sgtable(&sg_out, &prealloc_sg, dst, *dst_len);
	184	if (ret)
	185	goto out_tfm;
	186
e59dd982	187	crypto_skcipher_setkey((void *)tfm, key, key_len);
e9f6452e	188	memcpy(iv, aes_iv, AES_BLOCK_SIZE);
aaef3170	189
e59dd982 HX	190	skcipher_request_set_tfm(req, tfm);
	191	skcipher_request_set_callback(req, 0, NULL, NULL);
	192	skcipher_request_set_crypt(req, sg_in, sg_out.sgl,
	193	src_len + zero_padding, iv);
	194
8b6e4f2d SW	195	/*
	196	print_hex_dump(KERN_ERR, "enc key: ", DUMP_PREFIX_NONE, 16, 1,
	197	key, key_len, 1);
	198	print_hex_dump(KERN_ERR, "enc src: ", DUMP_PREFIX_NONE, 16, 1,
	199	src, src_len, 1);
	200	print_hex_dump(KERN_ERR, "enc pad: ", DUMP_PREFIX_NONE, 16, 1,
	201	pad, zero_padding, 1);
	202	*/
e59dd982 HX	203	ret = crypto_skcipher_encrypt(req);
e59dd982 HX	204	skcipher_request_zero(req);
aaef3170	205	if (ret < 0) {
8b6e4f2d	206	pr_err("ceph_aes_crypt failed %d\n", ret);
aaef3170 ID	207	goto out_sg;
aaef3170 ID	208	}
8b6e4f2d SW	209	/*
	210	print_hex_dump(KERN_ERR, "enc out: ", DUMP_PREFIX_NONE, 16, 1,
	211	dst, *dst_len, 1);
	212	*/
aaef3170 ID	213
	214	out_sg:
	215	teardown_sgtable(&sg_out);
	216	out_tfm:
e59dd982	217	crypto_free_skcipher(tfm);
aaef3170	218	return ret;
8b6e4f2d SW	219	}
8b6e4f2d SW	220
cd84db6e YS	221	static int ceph_aes_encrypt2(const void key, int key_len, void dst,
	222	size_t *dst_len,
	223	const void *src1, size_t src1_len,
	224	const void *src2, size_t src2_len)
8b6e4f2d	225	{
aaef3170 ID	226	struct scatterlist sg_in[3], prealloc_sg;
aaef3170 ID	227	struct sg_table sg_out;
e59dd982 HX	228	struct crypto_skcipher *tfm = ceph_crypto_alloc_cipher();
e59dd982 HX	229	SKCIPHER_REQUEST_ON_STACK(req, tfm);
8b6e4f2d	230	int ret;
e9f6452e	231	char iv[AES_BLOCK_SIZE];
8b6e4f2d SW	232	size_t zero_padding = (0x10 - ((src1_len + src2_len) & 0x0f));
	233	char pad[16];
	234
	235	if (IS_ERR(tfm))
	236	return PTR_ERR(tfm);
	237
	238	memset(pad, zero_padding, zero_padding);
	239
	240	*dst_len = src1_len + src2_len + zero_padding;
	241
8b6e4f2d SW	242	sg_init_table(sg_in, 3);
	243	sg_set_buf(&sg_in[0], src1, src1_len);
	244	sg_set_buf(&sg_in[1], src2, src2_len);
	245	sg_set_buf(&sg_in[2], pad, zero_padding);
aaef3170 ID	246	ret = setup_sgtable(&sg_out, &prealloc_sg, dst, *dst_len);
	247	if (ret)
	248	goto out_tfm;
	249
e59dd982	250	crypto_skcipher_setkey((void *)tfm, key, key_len);
e9f6452e	251	memcpy(iv, aes_iv, AES_BLOCK_SIZE);
aaef3170	252
e59dd982 HX	253	skcipher_request_set_tfm(req, tfm);
	254	skcipher_request_set_callback(req, 0, NULL, NULL);
	255	skcipher_request_set_crypt(req, sg_in, sg_out.sgl,
	256	src1_len + src2_len + zero_padding, iv);
	257
8b6e4f2d SW	258	/*
	259	print_hex_dump(KERN_ERR, "enc key: ", DUMP_PREFIX_NONE, 16, 1,
	260	key, key_len, 1);
	261	print_hex_dump(KERN_ERR, "enc src1: ", DUMP_PREFIX_NONE, 16, 1,
	262	src1, src1_len, 1);
	263	print_hex_dump(KERN_ERR, "enc src2: ", DUMP_PREFIX_NONE, 16, 1,
	264	src2, src2_len, 1);
	265	print_hex_dump(KERN_ERR, "enc pad: ", DUMP_PREFIX_NONE, 16, 1,
	266	pad, zero_padding, 1);
	267	*/
e59dd982 HX	268	ret = crypto_skcipher_encrypt(req);
e59dd982 HX	269	skcipher_request_zero(req);
aaef3170	270	if (ret < 0) {
8b6e4f2d	271	pr_err("ceph_aes_crypt2 failed %d\n", ret);
aaef3170 ID	272	goto out_sg;
aaef3170 ID	273	}
8b6e4f2d SW	274	/*
	275	print_hex_dump(KERN_ERR, "enc out: ", DUMP_PREFIX_NONE, 16, 1,
	276	dst, *dst_len, 1);
	277	*/
aaef3170 ID	278
	279	out_sg:
	280	teardown_sgtable(&sg_out);
	281	out_tfm:
e59dd982	282	crypto_free_skcipher(tfm);
aaef3170	283	return ret;
8b6e4f2d SW	284	}
8b6e4f2d SW	285
cd84db6e YS	286	static int ceph_aes_decrypt(const void *key, int key_len,
	287	void dst, size_t dst_len,
	288	const void *src, size_t src_len)
8b6e4f2d	289	{
aaef3170 ID	290	struct sg_table sg_in;
aaef3170 ID	291	struct scatterlist sg_out[2], prealloc_sg;
e59dd982 HX	292	struct crypto_skcipher *tfm = ceph_crypto_alloc_cipher();
e59dd982 HX	293	SKCIPHER_REQUEST_ON_STACK(req, tfm);
8b6e4f2d	294	char pad[16];
e9f6452e	295	char iv[AES_BLOCK_SIZE];
8b6e4f2d SW	296	int ret;
	297	int last_byte;
	298
	299	if (IS_ERR(tfm))
	300	return PTR_ERR(tfm);
	301
8b6e4f2d	302	sg_init_table(sg_out, 2);
8b6e4f2d SW	303	sg_set_buf(&sg_out[0], dst, *dst_len);
8b6e4f2d SW	304	sg_set_buf(&sg_out[1], pad, sizeof(pad));
aaef3170 ID	305	ret = setup_sgtable(&sg_in, &prealloc_sg, src, src_len);
	306	if (ret)
	307	goto out_tfm;
8b6e4f2d	308
e59dd982	309	crypto_skcipher_setkey((void *)tfm, key, key_len);
e9f6452e	310	memcpy(iv, aes_iv, AES_BLOCK_SIZE);
8b6e4f2d	311
e59dd982 HX	312	skcipher_request_set_tfm(req, tfm);
	313	skcipher_request_set_callback(req, 0, NULL, NULL);
	314	skcipher_request_set_crypt(req, sg_in.sgl, sg_out,
	315	src_len, iv);
	316
8b6e4f2d SW	317	/*
	318	print_hex_dump(KERN_ERR, "dec key: ", DUMP_PREFIX_NONE, 16, 1,
	319	key, key_len, 1);
	320	print_hex_dump(KERN_ERR, "dec in: ", DUMP_PREFIX_NONE, 16, 1,
	321	src, src_len, 1);
	322	*/
e59dd982 HX	323	ret = crypto_skcipher_decrypt(req);
e59dd982 HX	324	skcipher_request_zero(req);
8b6e4f2d SW	325	if (ret < 0) {
8b6e4f2d SW	326	pr_err("ceph_aes_decrypt failed %d\n", ret);
aaef3170	327	goto out_sg;
8b6e4f2d SW	328	}
	329
	330	if (src_len <= *dst_len)
	331	last_byte = ((char *)dst)[src_len - 1];
	332	else
	333	last_byte = pad[src_len - *dst_len - 1];
	334	if (last_byte <= 16 && src_len >= last_byte) {
	335	*dst_len = src_len - last_byte;
	336	} else {
	337	pr_err("ceph_aes_decrypt got bad padding %d on src len %d\n",
	338	last_byte, (int)src_len);
	339	return -EPERM; /* bad padding */
	340	}
	341	/*
	342	print_hex_dump(KERN_ERR, "dec out: ", DUMP_PREFIX_NONE, 16, 1,
	343	dst, *dst_len, 1);
	344	*/
aaef3170 ID	345
	346	out_sg:
	347	teardown_sgtable(&sg_in);
	348	out_tfm:
e59dd982	349	crypto_free_skcipher(tfm);
aaef3170	350	return ret;
8b6e4f2d SW	351	}
8b6e4f2d SW	352
cd84db6e YS	353	static int ceph_aes_decrypt2(const void *key, int key_len,
	354	void dst1, size_t dst1_len,
	355	void dst2, size_t dst2_len,
	356	const void *src, size_t src_len)
8b6e4f2d	357	{
aaef3170 ID	358	struct sg_table sg_in;
aaef3170 ID	359	struct scatterlist sg_out[3], prealloc_sg;
e59dd982 HX	360	struct crypto_skcipher *tfm = ceph_crypto_alloc_cipher();
e59dd982 HX	361	SKCIPHER_REQUEST_ON_STACK(req, tfm);
8b6e4f2d	362	char pad[16];
e9f6452e	363	char iv[AES_BLOCK_SIZE];
8b6e4f2d SW	364	int ret;
	365	int last_byte;
	366
	367	if (IS_ERR(tfm))
	368	return PTR_ERR(tfm);
	369
8b6e4f2d SW	370	sg_init_table(sg_out, 3);
	371	sg_set_buf(&sg_out[0], dst1, *dst1_len);
	372	sg_set_buf(&sg_out[1], dst2, *dst2_len);
	373	sg_set_buf(&sg_out[2], pad, sizeof(pad));
aaef3170 ID	374	ret = setup_sgtable(&sg_in, &prealloc_sg, src, src_len);
	375	if (ret)
	376	goto out_tfm;
8b6e4f2d	377
e59dd982	378	crypto_skcipher_setkey((void *)tfm, key, key_len);
e9f6452e	379	memcpy(iv, aes_iv, AES_BLOCK_SIZE);
8b6e4f2d	380
e59dd982 HX	381	skcipher_request_set_tfm(req, tfm);
	382	skcipher_request_set_callback(req, 0, NULL, NULL);
	383	skcipher_request_set_crypt(req, sg_in.sgl, sg_out,
	384	src_len, iv);
	385
8b6e4f2d SW	386	/*
	387	print_hex_dump(KERN_ERR, "dec key: ", DUMP_PREFIX_NONE, 16, 1,
	388	key, key_len, 1);
	389	print_hex_dump(KERN_ERR, "dec in: ", DUMP_PREFIX_NONE, 16, 1,
	390	src, src_len, 1);
	391	*/
e59dd982 HX	392	ret = crypto_skcipher_decrypt(req);
e59dd982 HX	393	skcipher_request_zero(req);
8b6e4f2d SW	394	if (ret < 0) {
8b6e4f2d SW	395	pr_err("ceph_aes_decrypt failed %d\n", ret);
aaef3170	396	goto out_sg;
8b6e4f2d SW	397	}
	398
	399	if (src_len <= *dst1_len)
	400	last_byte = ((char *)dst1)[src_len - 1];
	401	else if (src_len <= dst1_len + dst2_len)
	402	last_byte = ((char )dst2)[src_len - dst1_len - 1];
	403	else
	404	last_byte = pad[src_len - dst1_len - dst2_len - 1];
	405	if (last_byte <= 16 && src_len >= last_byte) {
	406	src_len -= last_byte;
	407	} else {
	408	pr_err("ceph_aes_decrypt got bad padding %d on src len %d\n",
	409	last_byte, (int)src_len);
	410	return -EPERM; /* bad padding */
	411	}
	412
	413	if (src_len < *dst1_len) {
	414	*dst1_len = src_len;
	415	*dst2_len = 0;
	416	} else {
	417	dst2_len = src_len - dst1_len;
	418	}
	419	/*
	420	print_hex_dump(KERN_ERR, "dec out1: ", DUMP_PREFIX_NONE, 16, 1,
	421	dst1, *dst1_len, 1);
	422	print_hex_dump(KERN_ERR, "dec out2: ", DUMP_PREFIX_NONE, 16, 1,
	423	dst2, *dst2_len, 1);
	424	*/
	425
aaef3170 ID	426	out_sg:
	427	teardown_sgtable(&sg_in);
	428	out_tfm:
e59dd982	429	crypto_free_skcipher(tfm);
aaef3170	430	return ret;
8b6e4f2d SW	431	}
	432
	433
	434	int ceph_decrypt(struct ceph_crypto_key secret, void dst, size_t *dst_len,
	435	const void *src, size_t src_len)
	436	{
	437	switch (secret->type) {
	438	case CEPH_CRYPTO_NONE:
	439	if (*dst_len < src_len)
	440	return -ERANGE;
	441	memcpy(dst, src, src_len);
	442	*dst_len = src_len;
	443	return 0;
	444
	445	case CEPH_CRYPTO_AES:
	446	return ceph_aes_decrypt(secret->key, secret->len, dst,
	447	dst_len, src, src_len);
	448
	449	default:
	450	return -EINVAL;
	451	}
	452	}
	453
	454	int ceph_decrypt2(struct ceph_crypto_key *secret,
	455	void dst1, size_t dst1_len,
	456	void dst2, size_t dst2_len,
	457	const void *src, size_t src_len)
	458	{
	459	size_t t;
	460
	461	switch (secret->type) {
	462	case CEPH_CRYPTO_NONE:
	463	if (dst1_len + dst2_len < src_len)
	464	return -ERANGE;
	465	t = min(*dst1_len, src_len);
	466	memcpy(dst1, src, t);
	467	*dst1_len = t;
	468	src += t;
	469	src_len -= t;
	470	if (src_len) {
	471	t = min(*dst2_len, src_len);
	472	memcpy(dst2, src, t);
	473	*dst2_len = t;
	474	}
	475	return 0;
	476
	477	case CEPH_CRYPTO_AES:
	478	return ceph_aes_decrypt2(secret->key, secret->len,
	479	dst1, dst1_len, dst2, dst2_len,
	480	src, src_len);
	481
	482	default:
	483	return -EINVAL;
	484	}
	485	}
	486
	487	int ceph_encrypt(struct ceph_crypto_key secret, void dst, size_t *dst_len,
	488	const void *src, size_t src_len)
	489	{
	490	switch (secret->type) {
	491	case CEPH_CRYPTO_NONE:
	492	if (*dst_len < src_len)
	493	return -ERANGE;
	494	memcpy(dst, src, src_len);
495	*dst_len = src_len;
496	return 0;
497
498	case CEPH_CRYPTO_AES:
499	return ceph_aes_encrypt(secret->key, secret->len, dst,
500	dst_len, src, src_len);
501
502	default:
503	return -EINVAL;
504	}
505	}
506
507	int ceph_encrypt2(struct ceph_crypto_key secret, void dst, size_t *dst_len,
508	const void *src1, size_t src1_len,
509	const void *src2, size_t src2_len)
510	{
511	switch (secret->type) {
512	case CEPH_CRYPTO_NONE:
513	if (*dst_len < src1_len + src2_len)
514	return -ERANGE;
515	memcpy(dst, src1, src1_len);
516	memcpy(dst + src1_len, src2, src2_len);
517	*dst_len = src1_len + src2_len;
518	return 0;
519
520	case CEPH_CRYPTO_AES:
521	return ceph_aes_encrypt2(secret->key, secret->len, dst, dst_len,
522	src1, src1_len, src2, src2_len);
523
524	default:
525	return -EINVAL;
526	}
527	}
4b2a58ab	528
efa64c09	529	static int ceph_key_preparse(struct key_preparsed_payload *prep)
4b2a58ab TV	530	{
4b2a58ab TV	531	struct ceph_crypto_key *ckey;
cf7f601c	532	size_t datalen = prep->datalen;
4b2a58ab TV	533	int ret;
	534	void *p;
	535
	536	ret = -EINVAL;
cf7f601c	537	if (datalen <= 0 \|\| datalen > 32767 \|\| !prep->data)
4b2a58ab TV	538	goto err;
4b2a58ab TV	539
4b2a58ab TV	540	ret = -ENOMEM;
	541	ckey = kmalloc(sizeof(*ckey), GFP_KERNEL);
	542	if (!ckey)
	543	goto err;
	544
	545	/* TODO ceph_crypto_key_decode should really take const input */
cf7f601c DH	546	p = (void *)prep->data;
cf7f601c DH	547	ret = ceph_crypto_key_decode(ckey, &p, (char*)prep->data+datalen);
4b2a58ab TV	548	if (ret < 0)
	549	goto err_ckey;
	550
146aa8b1	551	prep->payload.data[0] = ckey;
efa64c09	552	prep->quotalen = datalen;
4b2a58ab TV	553	return 0;
	554
	555	err_ckey:
	556	kfree(ckey);
	557	err:
	558	return ret;
	559	}
	560
efa64c09 DH	561	static void ceph_key_free_preparse(struct key_preparsed_payload *prep)
efa64c09 DH	562	{
146aa8b1	563	struct ceph_crypto_key *ckey = prep->payload.data[0];
efa64c09 DH	564	ceph_crypto_key_destroy(ckey);
	565	kfree(ckey);
	566	}
	567
efa64c09 DH	568	static void ceph_key_destroy(struct key *key)
efa64c09 DH	569	{
146aa8b1	570	struct ceph_crypto_key *ckey = key->payload.data[0];
4b2a58ab TV	571
4b2a58ab TV	572	ceph_crypto_key_destroy(ckey);
f0666b1a	573	kfree(ckey);
4b2a58ab TV	574	}
	575
	576	struct key_type key_type_ceph = {
	577	.name = "ceph",
efa64c09 DH	578	.preparse = ceph_key_preparse,
	579	.free_preparse = ceph_key_free_preparse,
	580	.instantiate = generic_key_instantiate,
4b2a58ab TV	581	.destroy = ceph_key_destroy,
	582	};
	583
	584	int ceph_crypto_init(void) {
	585	return register_key_type(&key_type_ceph);
	586	}
	587
	588	void ceph_crypto_shutdown(void) {
	589	unregister_key_type(&key_type_ceph);
	590	}