[mirror_ubuntu-bionic-kernel.git] / net / sunrpc / auth_gss / gss_krb5_crypto.c

/*
 *  linux/net/sunrpc/gss_krb5_crypto.c
 *
 *  Copyright (c) 2000 The Regents of the University of Michigan.
 *  All rights reserved.
 *
 *  Andy Adamson   <andros@umich.edu>
 *  Bruce Fields   <bfields@umich.edu>
 */

/*
 * Copyright (C) 1998 by the FundsXpress, INC.
 *
 * All rights reserved.
 *
 * Export of this software from the United States of America may require
 * a specific license from the United States Government.  It is the
 * responsibility of any person or organization contemplating export to
 * obtain such a license before exporting.
 *
 * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
 * distribute this software and its documentation for any purpose and
 * without fee is hereby granted, provided that the above copyright
 * notice appear in all copies and that both that copyright notice and
 * this permission notice appear in supporting documentation, and that
 * the name of FundsXpress. not be used in advertising or publicity pertaining
 * to distribution of the software without specific, written prior
 * permission.  FundsXpress makes no representations about the suitability of
 * this software for any purpose.  It is provided "as is" without express
 * or implied warranty.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#include <linux/err.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/scatterlist.h>
#include <linux/crypto.h>
#include <linux/highmem.h>
#include <linux/pagemap.h>
#include <linux/sunrpc/gss_krb5.h>
#include <linux/sunrpc/xdr.h>

#ifdef RPC_DEBUG
# define RPCDBG_FACILITY        RPCDBG_AUTH
#endif

u32
krb5_encrypt(
	struct crypto_blkcipher *tfm,
	void * iv,
	void * in,
	void * out,
	int length)
{
	u32 ret = -EINVAL;
        struct scatterlist sg[1];
	u8 local_iv[16] = {0};
	struct blkcipher_desc desc = { .tfm = tfm, .info = local_iv };

	if (length % crypto_blkcipher_blocksize(tfm) != 0)
		goto out;

	if (crypto_blkcipher_ivsize(tfm) > 16) {
		dprintk("RPC:      gss_k5encrypt: tfm iv size to large %d\n",
		         crypto_blkcipher_ivsize(tfm));
		goto out;
	}

	if (iv)
		memcpy(local_iv, iv, crypto_blkcipher_ivsize(tfm));

	memcpy(out, in, length);
	sg_set_buf(sg, out, length);

	ret = crypto_blkcipher_encrypt_iv(&desc, sg, sg, length);
out:
	dprintk("RPC:      krb5_encrypt returns %d\n",ret);
	return ret;
}

EXPORT_SYMBOL(krb5_encrypt);

u32
krb5_decrypt(
     struct crypto_blkcipher *tfm,
     void * iv,
     void * in,
     void * out,
     int length)
{
	u32 ret = -EINVAL;
	struct scatterlist sg[1];
	u8 local_iv[16] = {0};
	struct blkcipher_desc desc = { .tfm = tfm, .info = local_iv };

	if (length % crypto_blkcipher_blocksize(tfm) != 0)
		goto out;

	if (crypto_blkcipher_ivsize(tfm) > 16) {
		dprintk("RPC:      gss_k5decrypt: tfm iv size to large %d\n",
			crypto_blkcipher_ivsize(tfm));
		goto out;
	}
	if (iv)
		memcpy(local_iv,iv, crypto_blkcipher_ivsize(tfm));

	memcpy(out, in, length);
	sg_set_buf(sg, out, length);

	ret = crypto_blkcipher_decrypt_iv(&desc, sg, sg, length);
out:
	dprintk("RPC:      gss_k5decrypt returns %d\n",ret);
	return ret;
}

EXPORT_SYMBOL(krb5_decrypt);

static int
checksummer(struct scatterlist *sg, void *data)
{
	struct hash_desc *desc = data;

	return crypto_hash_update(desc, sg, sg->length);
}

/* checksum the plaintext data and hdrlen bytes of the token header */
s32
make_checksum(s32 cksumtype, char *header, int hdrlen, struct xdr_buf *body,
		   int body_offset, struct xdr_netobj *cksum)
{
	char                            *cksumname;
	struct hash_desc                desc; /* XXX add to ctx? */
	struct scatterlist              sg[1];
	int err;

	switch (cksumtype) {
		case CKSUMTYPE_RSA_MD5:
			cksumname = "md5";
			break;
		default:
			dprintk("RPC:      krb5_make_checksum:"
				" unsupported checksum %d", cksumtype);
			return GSS_S_FAILURE;
	}
	desc.tfm = crypto_alloc_hash(cksumname, 0, CRYPTO_ALG_ASYNC);
	if (IS_ERR(desc.tfm))
		return GSS_S_FAILURE;
	cksum->len = crypto_hash_digestsize(desc.tfm);
	desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;

	err = crypto_hash_init(&desc);
	if (err)
		goto out;
	sg_set_buf(sg, header, hdrlen);
	err = crypto_hash_update(&desc, sg, hdrlen);
	if (err)
		goto out;
	err = xdr_process_buf(body, body_offset, body->len - body_offset,
			      checksummer, &desc);
	if (err)
		goto out;
	err = crypto_hash_final(&desc, cksum->data);

out:
	crypto_free_hash(desc.tfm);
	return err ? GSS_S_FAILURE : 0;
}

EXPORT_SYMBOL(make_checksum);

struct encryptor_desc {
	u8 iv[8]; /* XXX hard-coded blocksize */
	struct blkcipher_desc desc;
	int pos;
	struct xdr_buf *outbuf;
	struct page **pages;
	struct scatterlist infrags[4];
	struct scatterlist outfrags[4];
	int fragno;
	int fraglen;
};

static int
encryptor(struct scatterlist *sg, void *data)
{
	struct encryptor_desc *desc = data;
	struct xdr_buf *outbuf = desc->outbuf;
	struct page *in_page;
	int thislen = desc->fraglen + sg->length;
	int fraglen, ret;
	int page_pos;

	/* Worst case is 4 fragments: head, end of page 1, start
	 * of page 2, tail.  Anything more is a bug. */
	BUG_ON(desc->fragno > 3);
	desc->infrags[desc->fragno] = *sg;
	desc->outfrags[desc->fragno] = *sg;

	page_pos = desc->pos - outbuf->head[0].iov_len;
	if (page_pos >= 0 && page_pos < outbuf->page_len) {
		/* pages are not in place: */
		int i = (page_pos + outbuf->page_base) >> PAGE_CACHE_SHIFT;
		in_page = desc->pages[i];
	} else {
		in_page = sg->page;
	}
	desc->infrags[desc->fragno].page = in_page;
	desc->fragno++;
	desc->fraglen += sg->length;
	desc->pos += sg->length;

	fraglen = thislen & 7; /* XXX hardcoded blocksize */
	thislen -= fraglen;

	if (thislen == 0)
		return 0;

	ret = crypto_blkcipher_encrypt_iv(&desc->desc, desc->outfrags,
					  desc->infrags, thislen);
	if (ret)
		return ret;
	if (fraglen) {
		desc->outfrags[0].page = sg->page;
		desc->outfrags[0].offset = sg->offset + sg->length - fraglen;
		desc->outfrags[0].length = fraglen;
		desc->infrags[0] = desc->outfrags[0];
		desc->infrags[0].page = in_page;
		desc->fragno = 1;
		desc->fraglen = fraglen;
	} else {
		desc->fragno = 0;
		desc->fraglen = 0;
	}
	return 0;
}

int
gss_encrypt_xdr_buf(struct crypto_blkcipher *tfm, struct xdr_buf *buf,
		    int offset, struct page **pages)
{
	int ret;
	struct encryptor_desc desc;

	BUG_ON((buf->len - offset) % crypto_blkcipher_blocksize(tfm) != 0);

	memset(desc.iv, 0, sizeof(desc.iv));
	desc.desc.tfm = tfm;
	desc.desc.info = desc.iv;
	desc.desc.flags = 0;
	desc.pos = offset;
	desc.outbuf = buf;
	desc.pages = pages;
	desc.fragno = 0;
	desc.fraglen = 0;

	ret = xdr_process_buf(buf, offset, buf->len - offset, encryptor, &desc);
	return ret;
}

EXPORT_SYMBOL(gss_encrypt_xdr_buf);

struct decryptor_desc {
	u8 iv[8]; /* XXX hard-coded blocksize */
	struct blkcipher_desc desc;
	struct scatterlist frags[4];
	int fragno;
	int fraglen;
};

static int
decryptor(struct scatterlist *sg, void *data)
{
	struct decryptor_desc *desc = data;
	int thislen = desc->fraglen + sg->length;
	int fraglen, ret;

	/* Worst case is 4 fragments: head, end of page 1, start
	 * of page 2, tail.  Anything more is a bug. */
	BUG_ON(desc->fragno > 3);
	desc->frags[desc->fragno] = *sg;
	desc->fragno++;
	desc->fraglen += sg->length;

	fraglen = thislen & 7; /* XXX hardcoded blocksize */
	thislen -= fraglen;

	if (thislen == 0)
		return 0;

	ret = crypto_blkcipher_decrypt_iv(&desc->desc, desc->frags,
					  desc->frags, thislen);
	if (ret)
		return ret;
	if (fraglen) {
		desc->frags[0].page = sg->page;
		desc->frags[0].offset = sg->offset + sg->length - fraglen;
		desc->frags[0].length = fraglen;
		desc->fragno = 1;
		desc->fraglen = fraglen;
	} else {
		desc->fragno = 0;
		desc->fraglen = 0;
	}
	return 0;
}

int
gss_decrypt_xdr_buf(struct crypto_blkcipher *tfm, struct xdr_buf *buf,
		    int offset)
{
	struct decryptor_desc desc;

	/* XXXJBF: */
	BUG_ON((buf->len - offset) % crypto_blkcipher_blocksize(tfm) != 0);

	memset(desc.iv, 0, sizeof(desc.iv));
	desc.desc.tfm = tfm;
	desc.desc.info = desc.iv;
	desc.desc.flags = 0;
	desc.fragno = 0;
	desc.fraglen = 0;
	return xdr_process_buf(buf, offset, buf->len - offset, decryptor, &desc);
}

EXPORT_SYMBOL(gss_decrypt_xdr_buf);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/net/sunrpc/gss_krb5_crypto.c
	3	*
	4	* Copyright (c) 2000 The Regents of the University of Michigan.
	5	* All rights reserved.
	6	*
	7	* Andy Adamson <andros@umich.edu>
	8	* Bruce Fields <bfields@umich.edu>
	9	*/
	10
	11	/*
	12	* Copyright (C) 1998 by the FundsXpress, INC.
	13	*
	14	* All rights reserved.
	15	*
	16	* Export of this software from the United States of America may require
	17	* a specific license from the United States Government. It is the
	18	* responsibility of any person or organization contemplating export to
	19	* obtain such a license before exporting.
	20	*
	21	* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
	22	* distribute this software and its documentation for any purpose and
	23	* without fee is hereby granted, provided that the above copyright
	24	* notice appear in all copies and that both that copyright notice and
	25	* this permission notice appear in supporting documentation, and that
	26	* the name of FundsXpress. not be used in advertising or publicity pertaining
	27	* to distribution of the software without specific, written prior
	28	* permission. FundsXpress makes no representations about the suitability of
	29	* this software for any purpose. It is provided "as is" without express
	30	* or implied warranty.
	31	*
	32	* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
	33	* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
	34	* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
	35	*/
	36
35058687	37	#include <linux/err.h>
1da177e4 LT	38	#include <linux/types.h>
	39	#include <linux/mm.h>
	40	#include <linux/slab.h>
378f058c	41	#include <linux/scatterlist.h>
1da177e4 LT	42	#include <linux/crypto.h>
	43	#include <linux/highmem.h>
	44	#include <linux/pagemap.h>
	45	#include <linux/sunrpc/gss_krb5.h>
37a4e6cb	46	#include <linux/sunrpc/xdr.h>
1da177e4 LT	47
	48	#ifdef RPC_DEBUG
	49	# define RPCDBG_FACILITY RPCDBG_AUTH
	50	#endif
	51
	52	u32
	53	krb5_encrypt(
378c6697	54	struct crypto_blkcipher *tfm,
1da177e4 LT	55	void * iv,
	56	void * in,
	57	void * out,
	58	int length)
	59	{
	60	u32 ret = -EINVAL;
	61	struct scatterlist sg[1];
	62	u8 local_iv[16] = {0};
378c6697	63	struct blkcipher_desc desc = { .tfm = tfm, .info = local_iv };
1da177e4	64
378c6697	65	if (length % crypto_blkcipher_blocksize(tfm) != 0)
1da177e4 LT	66	goto out;
1da177e4 LT	67
378c6697	68	if (crypto_blkcipher_ivsize(tfm) > 16) {
1da177e4	69	dprintk("RPC: gss_k5encrypt: tfm iv size to large %d\n",
378c6697	70	crypto_blkcipher_ivsize(tfm));
1da177e4 LT	71	goto out;
	72	}
	73
	74	if (iv)
378c6697	75	memcpy(local_iv, iv, crypto_blkcipher_ivsize(tfm));
1da177e4 LT	76
1da177e4 LT	77	memcpy(out, in, length);
6df5b9f4	78	sg_set_buf(sg, out, length);
1da177e4	79
378c6697	80	ret = crypto_blkcipher_encrypt_iv(&desc, sg, sg, length);
1da177e4 LT	81	out:
1da177e4 LT	82	dprintk("RPC: krb5_encrypt returns %d\n",ret);
8fc7500b	83	return ret;
1da177e4 LT	84	}
	85
	86	EXPORT_SYMBOL(krb5_encrypt);
	87
	88	u32
	89	krb5_decrypt(
378c6697	90	struct crypto_blkcipher *tfm,
1da177e4 LT	91	void * iv,
	92	void * in,
	93	void * out,
	94	int length)
	95	{
	96	u32 ret = -EINVAL;
	97	struct scatterlist sg[1];
	98	u8 local_iv[16] = {0};
378c6697	99	struct blkcipher_desc desc = { .tfm = tfm, .info = local_iv };
1da177e4	100
378c6697	101	if (length % crypto_blkcipher_blocksize(tfm) != 0)
1da177e4 LT	102	goto out;
1da177e4 LT	103
378c6697	104	if (crypto_blkcipher_ivsize(tfm) > 16) {
1da177e4	105	dprintk("RPC: gss_k5decrypt: tfm iv size to large %d\n",
378c6697	106	crypto_blkcipher_ivsize(tfm));
1da177e4 LT	107	goto out;
	108	}
	109	if (iv)
378c6697	110	memcpy(local_iv,iv, crypto_blkcipher_ivsize(tfm));
1da177e4 LT	111
1da177e4 LT	112	memcpy(out, in, length);
6df5b9f4	113	sg_set_buf(sg, out, length);
1da177e4	114
378c6697	115	ret = crypto_blkcipher_decrypt_iv(&desc, sg, sg, length);
1da177e4 LT	116	out:
1da177e4 LT	117	dprintk("RPC: gss_k5decrypt returns %d\n",ret);
8fc7500b	118	return ret;
1da177e4 LT	119	}
	120
	121	EXPORT_SYMBOL(krb5_decrypt);
	122
f7b3af64 BF	123	static int
	124	checksummer(struct scatterlist sg, void data)
	125	{
35058687	126	struct hash_desc *desc = data;
f7b3af64	127
35058687	128	return crypto_hash_update(desc, sg, sg->length);
f7b3af64 BF	129	}
f7b3af64 BF	130
1da177e4 LT	131	/* checksum the plaintext data and hdrlen bytes of the token header */
	132	s32
	133	make_checksum(s32 cksumtype, char header, int hdrlen, struct xdr_buf body,
14ae162c	134	int body_offset, struct xdr_netobj *cksum)
1da177e4 LT	135	{
1da177e4 LT	136	char *cksumname;
35058687	137	struct hash_desc desc; /* XXX add to ctx? */
1da177e4	138	struct scatterlist sg[1];
35058687	139	int err;
1da177e4 LT	140
	141	switch (cksumtype) {
	142	case CKSUMTYPE_RSA_MD5:
	143	cksumname = "md5";
	144	break;
	145	default:
	146	dprintk("RPC: krb5_make_checksum:"
	147	" unsupported checksum %d", cksumtype);
d4a30e7e	148	return GSS_S_FAILURE;
1da177e4	149	}
35058687 HX	150	desc.tfm = crypto_alloc_hash(cksumname, 0, CRYPTO_ALG_ASYNC);
35058687 HX	151	if (IS_ERR(desc.tfm))
d4a30e7e	152	return GSS_S_FAILURE;
35058687 HX	153	cksum->len = crypto_hash_digestsize(desc.tfm);
35058687 HX	154	desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
1da177e4	155
35058687 HX	156	err = crypto_hash_init(&desc);
	157	if (err)
	158	goto out;
378f058c	159	sg_set_buf(sg, header, hdrlen);
35058687 HX	160	err = crypto_hash_update(&desc, sg, hdrlen);
	161	if (err)
	162	goto out;
37a4e6cb	163	err = xdr_process_buf(body, body_offset, body->len - body_offset,
35058687 HX	164	checksummer, &desc);
	165	if (err)
	166	goto out;
	167	err = crypto_hash_final(&desc, cksum->data);
	168
	169	out:
	170	crypto_free_hash(desc.tfm);
	171	return err ? GSS_S_FAILURE : 0;
1da177e4 LT	172	}
	173
	174	EXPORT_SYMBOL(make_checksum);
14ae162c BF	175
	176	struct encryptor_desc {
	177	u8 iv[8]; /* XXX hard-coded blocksize */
378c6697	178	struct blkcipher_desc desc;
14ae162c BF	179	int pos;
	180	struct xdr_buf *outbuf;
	181	struct page **pages;
	182	struct scatterlist infrags[4];
	183	struct scatterlist outfrags[4];
	184	int fragno;
	185	int fraglen;
	186	};
	187
	188	static int
	189	encryptor(struct scatterlist sg, void data)
	190	{
	191	struct encryptor_desc *desc = data;
	192	struct xdr_buf *outbuf = desc->outbuf;
	193	struct page *in_page;
	194	int thislen = desc->fraglen + sg->length;
	195	int fraglen, ret;
	196	int page_pos;
	197
	198	/* Worst case is 4 fragments: head, end of page 1, start
	199	* of page 2, tail. Anything more is a bug. */
	200	BUG_ON(desc->fragno > 3);
	201	desc->infrags[desc->fragno] = *sg;
	202	desc->outfrags[desc->fragno] = *sg;
	203
	204	page_pos = desc->pos - outbuf->head[0].iov_len;
	205	if (page_pos >= 0 && page_pos < outbuf->page_len) {
	206	/* pages are not in place: */
	207	int i = (page_pos + outbuf->page_base) >> PAGE_CACHE_SHIFT;
	208	in_page = desc->pages[i];
	209	} else {
	210	in_page = sg->page;
	211	}
	212	desc->infrags[desc->fragno].page = in_page;
	213	desc->fragno++;
	214	desc->fraglen += sg->length;
	215	desc->pos += sg->length;
	216
	217	fraglen = thislen & 7; /* XXX hardcoded blocksize */
	218	thislen -= fraglen;
	219
	220	if (thislen == 0)
	221	return 0;
	222
378c6697 HX	223	ret = crypto_blkcipher_encrypt_iv(&desc->desc, desc->outfrags,
378c6697 HX	224	desc->infrags, thislen);
14ae162c BF	225	if (ret)
	226	return ret;
	227	if (fraglen) {
	228	desc->outfrags[0].page = sg->page;
	229	desc->outfrags[0].offset = sg->offset + sg->length - fraglen;
	230	desc->outfrags[0].length = fraglen;
	231	desc->infrags[0] = desc->outfrags[0];
	232	desc->infrags[0].page = in_page;
	233	desc->fragno = 1;
	234	desc->fraglen = fraglen;
	235	} else {
	236	desc->fragno = 0;
	237	desc->fraglen = 0;
	238	}
	239	return 0;
	240	}
	241
	242	int
378c6697 HX	243	gss_encrypt_xdr_buf(struct crypto_blkcipher tfm, struct xdr_buf buf,
378c6697 HX	244	int offset, struct page **pages)
14ae162c BF	245	{
	246	int ret;
	247	struct encryptor_desc desc;
	248
378c6697	249	BUG_ON((buf->len - offset) % crypto_blkcipher_blocksize(tfm) != 0);
14ae162c BF	250
14ae162c BF	251	memset(desc.iv, 0, sizeof(desc.iv));
378c6697 HX	252	desc.desc.tfm = tfm;
	253	desc.desc.info = desc.iv;
	254	desc.desc.flags = 0;
14ae162c BF	255	desc.pos = offset;
	256	desc.outbuf = buf;
	257	desc.pages = pages;
	258	desc.fragno = 0;
	259	desc.fraglen = 0;
	260
37a4e6cb	261	ret = xdr_process_buf(buf, offset, buf->len - offset, encryptor, &desc);
14ae162c BF	262	return ret;
	263	}
	264
	265	EXPORT_SYMBOL(gss_encrypt_xdr_buf);
	266
	267	struct decryptor_desc {
	268	u8 iv[8]; /* XXX hard-coded blocksize */
378c6697	269	struct blkcipher_desc desc;
14ae162c BF	270	struct scatterlist frags[4];
	271	int fragno;
	272	int fraglen;
	273	};
	274
	275	static int
	276	decryptor(struct scatterlist sg, void data)
	277	{
	278	struct decryptor_desc *desc = data;
	279	int thislen = desc->fraglen + sg->length;
	280	int fraglen, ret;
	281
	282	/* Worst case is 4 fragments: head, end of page 1, start
	283	* of page 2, tail. Anything more is a bug. */
	284	BUG_ON(desc->fragno > 3);
	285	desc->frags[desc->fragno] = *sg;
	286	desc->fragno++;
	287	desc->fraglen += sg->length;
	288
	289	fraglen = thislen & 7; /* XXX hardcoded blocksize */
	290	thislen -= fraglen;
	291
	292	if (thislen == 0)
	293	return 0;
	294
378c6697 HX	295	ret = crypto_blkcipher_decrypt_iv(&desc->desc, desc->frags,
378c6697 HX	296	desc->frags, thislen);
14ae162c BF	297	if (ret)
	298	return ret;
	299	if (fraglen) {
	300	desc->frags[0].page = sg->page;
	301	desc->frags[0].offset = sg->offset + sg->length - fraglen;
	302	desc->frags[0].length = fraglen;
	303	desc->fragno = 1;
	304	desc->fraglen = fraglen;
	305	} else {
	306	desc->fragno = 0;
	307	desc->fraglen = 0;
	308	}
	309	return 0;
	310	}
	311
	312	int
378c6697 HX	313	gss_decrypt_xdr_buf(struct crypto_blkcipher tfm, struct xdr_buf buf,
378c6697 HX	314	int offset)
14ae162c BF	315	{
	316	struct decryptor_desc desc;
	317
	318	/* XXXJBF: */
378c6697	319	BUG_ON((buf->len - offset) % crypto_blkcipher_blocksize(tfm) != 0);
14ae162c BF	320
14ae162c BF	321	memset(desc.iv, 0, sizeof(desc.iv));
378c6697 HX	322	desc.desc.tfm = tfm;
	323	desc.desc.info = desc.iv;
	324	desc.desc.flags = 0;
14ae162c BF	325	desc.fragno = 0;
14ae162c BF	326	desc.fraglen = 0;
37a4e6cb	327	return xdr_process_buf(buf, offset, buf->len - offset, decryptor, &desc);
14ae162c BF	328	}
	329
	330	EXPORT_SYMBOL(gss_decrypt_xdr_buf);