[mirror_ubuntu-artful-kernel.git] / fs / cifs / cifs_spnego.c

/*
 *   fs/cifs/cifs_spnego.c -- SPNEGO upcall management for CIFS
 *
 *   Copyright (c) 2007 Red Hat, Inc.
 *   Author(s): Jeff Layton (jlayton@redhat.com)
 *
 *   This library is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU Lesser General Public License as published
 *   by the Free Software Foundation; either version 2.1 of the License, or
 *   (at your option) any later version.
 *
 *   This library is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 *   the GNU Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public License
 *   along with this library; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <linux/list.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <keys/user-type.h>
#include <linux/key-type.h>
#include <linux/inet.h>
#include "cifsglob.h"
#include "cifs_spnego.h"
#include "cifs_debug.h"

/* create a new cifs key */
static int
cifs_spnego_key_instantiate(struct key *key, struct key_preparsed_payload *prep)
{
	char *payload;
	int ret;

	ret = -ENOMEM;
	payload = kmalloc(prep->datalen, GFP_KERNEL);
	if (!payload)
		goto error;

	/* attach the data */
	memcpy(payload, prep->data, prep->datalen);
	key->payload.data = payload;
	ret = 0;

error:
	return ret;
}

static void
cifs_spnego_key_destroy(struct key *key)
{
	kfree(key->payload.data);
}


/*
 * keytype for CIFS spnego keys
 */
struct key_type cifs_spnego_key_type = {
	.name		= "cifs.spnego",
	.instantiate	= cifs_spnego_key_instantiate,
	.match		= user_match,
	.destroy	= cifs_spnego_key_destroy,
	.describe	= user_describe,
};

/* length of longest version string e.g.  strlen("ver=0xFF") */
#define MAX_VER_STR_LEN		8

/* length of longest security mechanism name, eg in future could have
 * strlen(";sec=ntlmsspi") */
#define MAX_MECH_STR_LEN	13

/* strlen of "host=" */
#define HOST_KEY_LEN		5

/* strlen of ";ip4=" or ";ip6=" */
#define IP_KEY_LEN		5

/* strlen of ";uid=0x" */
#define UID_KEY_LEN		7

/* strlen of ";creduid=0x" */
#define CREDUID_KEY_LEN		11

/* strlen of ";user=" */
#define USER_KEY_LEN		6

/* strlen of ";pid=0x" */
#define PID_KEY_LEN		7

/* get a key struct with a SPNEGO security blob, suitable for session setup */
struct key *
cifs_get_spnego_key(struct cifs_ses *sesInfo)
{
	struct TCP_Server_Info *server = sesInfo->server;
	struct sockaddr_in *sa = (struct sockaddr_in *) &server->dstaddr;
	struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *) &server->dstaddr;
	char *description, *dp;
	size_t desc_len;
	struct key *spnego_key;
	const char *hostname = server->hostname;

	/* length of fields (with semicolons): ver=0xyz ip4=ipaddress
	   host=hostname sec=mechanism uid=0xFF user=username */
	desc_len = MAX_VER_STR_LEN +
		   HOST_KEY_LEN + strlen(hostname) +
		   IP_KEY_LEN + INET6_ADDRSTRLEN +
		   MAX_MECH_STR_LEN +
		   UID_KEY_LEN + (sizeof(uid_t) * 2) +
		   CREDUID_KEY_LEN + (sizeof(uid_t) * 2) +
		   PID_KEY_LEN + (sizeof(pid_t) * 2) + 1;

	if (sesInfo->user_name)
		desc_len += USER_KEY_LEN + strlen(sesInfo->user_name);

	spnego_key = ERR_PTR(-ENOMEM);
	description = kzalloc(desc_len, GFP_KERNEL);
	if (description == NULL)
		goto out;

	dp = description;
	/* start with version and hostname portion of UNC string */
	spnego_key = ERR_PTR(-EINVAL);
	sprintf(dp, "ver=0x%x;host=%s;", CIFS_SPNEGO_UPCALL_VERSION,
		hostname);
	dp = description + strlen(description);

	/* add the server address */
	if (server->dstaddr.ss_family == AF_INET)
		sprintf(dp, "ip4=%pI4", &sa->sin_addr);
	else if (server->dstaddr.ss_family == AF_INET6)
		sprintf(dp, "ip6=%pI6", &sa6->sin6_addr);
	else
		goto out;

	dp = description + strlen(description);

	/* for now, only sec=krb5 and sec=mskrb5 are valid */
	if (server->sec_kerberos)
		sprintf(dp, ";sec=krb5");
	else if (server->sec_mskerberos)
		sprintf(dp, ";sec=mskrb5");
	else
		goto out;

	dp = description + strlen(description);
	sprintf(dp, ";uid=0x%x",
		from_kuid_munged(&init_user_ns, sesInfo->linux_uid));

	dp = description + strlen(description);
	sprintf(dp, ";creduid=0x%x",
		from_kuid_munged(&init_user_ns, sesInfo->cred_uid));

	if (sesInfo->user_name) {
		dp = description + strlen(description);
		sprintf(dp, ";user=%s", sesInfo->user_name);
	}

	dp = description + strlen(description);
	sprintf(dp, ";pid=0x%x", current->pid);

	cFYI(1, "key description = %s", description);
	spnego_key = request_key(&cifs_spnego_key_type, description, "");

#ifdef CONFIG_CIFS_DEBUG2
	if (cifsFYI && !IS_ERR(spnego_key)) {
		struct cifs_spnego_msg *msg = spnego_key->payload.data;
		cifs_dump_mem("SPNEGO reply blob:", msg->data, min(1024U,
				msg->secblob_len + msg->sesskey_len));
	}
#endif /* CONFIG_CIFS_DEBUG2 */

out:
	kfree(description);
	return spnego_key;
}
Commit	Line	Data
f1d662a7 SF	1	/*
	2	* fs/cifs/cifs_spnego.c -- SPNEGO upcall management for CIFS
	3	*
	4	* Copyright (c) 2007 Red Hat, Inc.
	5	* Author(s): Jeff Layton (jlayton@redhat.com)
	6	*
	7	* This library is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU Lesser General Public License as published
	9	* by the Free Software Foundation; either version 2.1 of the License, or
	10	* (at your option) any later version.
	11	*
	12	* This library is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
	15	* the GNU Lesser General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU Lesser General Public License
	18	* along with this library; if not, write to the Free Software
	19	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	20	*/
	21
	22	#include <linux/list.h>
5a0e3ad6	23	#include <linux/slab.h>
f1d662a7 SF	24	#include <linux/string.h>
	25	#include <keys/user-type.h>
	26	#include <linux/key-type.h>
50b64e3b	27	#include <linux/inet.h>
f1d662a7 SF	28	#include "cifsglob.h"
	29	#include "cifs_spnego.h"
	30	#include "cifs_debug.h"
	31
	32	/* create a new cifs key */
	33	static int
cf7f601c	34	cifs_spnego_key_instantiate(struct key key, struct key_preparsed_payload prep)
f1d662a7 SF	35	{
	36	char *payload;
	37	int ret;
	38
	39	ret = -ENOMEM;
cf7f601c	40	payload = kmalloc(prep->datalen, GFP_KERNEL);
f1d662a7 SF	41	if (!payload)
	42	goto error;
	43
	44	/* attach the data */
cf7f601c	45	memcpy(payload, prep->data, prep->datalen);
d9fb5c09	46	key->payload.data = payload;
f1d662a7 SF	47	ret = 0;
	48
	49	error:
	50	return ret;
	51	}
	52
	53	static void
	54	cifs_spnego_key_destroy(struct key *key)
	55	{
	56	kfree(key->payload.data);
	57	}
	58
	59
	60	/*
	61	* keytype for CIFS spnego keys
	62	*/
	63	struct key_type cifs_spnego_key_type = {
	64	.name = "cifs.spnego",
	65	.instantiate = cifs_spnego_key_instantiate,
	66	.match = user_match,
	67	.destroy = cifs_spnego_key_destroy,
	68	.describe = user_describe,
	69	};
	70
7c9c3760 SF	71	/* length of longest version string e.g. strlen("ver=0xFF") */
	72	#define MAX_VER_STR_LEN 8
	73
	74	/* length of longest security mechanism name, eg in future could have
	75	* strlen(";sec=ntlmsspi") */
	76	#define MAX_MECH_STR_LEN 13
	77
7c9c3760 SF	78	/* strlen of "host=" */
	79	#define HOST_KEY_LEN 5
	80
	81	/* strlen of ";ip4=" or ";ip6=" */
	82	#define IP_KEY_LEN 5
	83
	84	/* strlen of ";uid=0x" */
	85	#define UID_KEY_LEN 7
	86
ba5dadbf JL	87	/* strlen of ";creduid=0x" */
	88	#define CREDUID_KEY_LEN 11
	89
7c9c3760 SF	90	/* strlen of ";user=" */
	91	#define USER_KEY_LEN 6
	92
c4c1bff6 JL	93	/* strlen of ";pid=0x" */
	94	#define PID_KEY_LEN 7
	95
f1d662a7 SF	96	/* get a key struct with a SPNEGO security blob, suitable for session setup */
f1d662a7 SF	97	struct key *
96daf2b0	98	cifs_get_spnego_key(struct cifs_ses *sesInfo)
f1d662a7 SF	99	{
f1d662a7 SF	100	struct TCP_Server_Info *server = sesInfo->server;
a9f1b85e PS	101	struct sockaddr_in sa = (struct sockaddr_in ) &server->dstaddr;
a9f1b85e PS	102	struct sockaddr_in6 sa6 = (struct sockaddr_in6 ) &server->dstaddr;
f1d662a7 SF	103	char description, dp;
	104	size_t desc_len;
	105	struct key *spnego_key;
d6c2e4d0	106	const char *hostname = server->hostname;
f1d662a7	107
66b8bd3c JL	108	/* length of fields (with semicolons): ver=0xyz ip4=ipaddress
	109	host=hostname sec=mechanism uid=0xFF user=username */
	110	desc_len = MAX_VER_STR_LEN +
7c9c3760	111	HOST_KEY_LEN + strlen(hostname) +
50b64e3b	112	IP_KEY_LEN + INET6_ADDRSTRLEN +
66b8bd3c	113	MAX_MECH_STR_LEN +
7c9c3760	114	UID_KEY_LEN + (sizeof(uid_t) * 2) +
ba5dadbf	115	CREDUID_KEY_LEN + (sizeof(uid_t) * 2) +
c4c1bff6	116	PID_KEY_LEN + (sizeof(pid_t) * 2) + 1;
66b8bd3c	117
04febabc JL	118	if (sesInfo->user_name)
	119	desc_len += USER_KEY_LEN + strlen(sesInfo->user_name);
	120
f1d662a7 SF	121	spnego_key = ERR_PTR(-ENOMEM);
	122	description = kzalloc(desc_len, GFP_KERNEL);
	123	if (description == NULL)
	124	goto out;
	125
	126	dp = description;
	127	/* start with version and hostname portion of UNC string */
	128	spnego_key = ERR_PTR(-EINVAL);
68bf728a	129	sprintf(dp, "ver=0x%x;host=%s;", CIFS_SPNEGO_UPCALL_VERSION,
f1d662a7 SF	130	hostname);
	131	dp = description + strlen(description);
	132
	133	/* add the server address */
a9f1b85e PS	134	if (server->dstaddr.ss_family == AF_INET)
	135	sprintf(dp, "ip4=%pI4", &sa->sin_addr);
	136	else if (server->dstaddr.ss_family == AF_INET6)
	137	sprintf(dp, "ip6=%pI6", &sa6->sin6_addr);
f1d662a7 SF	138	else
	139	goto out;
	140
	141	dp = description + strlen(description);
	142
c16fefa5	143	/* for now, only sec=krb5 and sec=mskrb5 are valid */
26efa0ba	144	if (server->sec_kerberos)
f1d662a7	145	sprintf(dp, ";sec=krb5");
26efa0ba	146	else if (server->sec_mskerberos)
c16fefa5	147	sprintf(dp, ";sec=mskrb5");
f1d662a7 SF	148	else
	149	goto out;
	150
9eae8a89	151	dp = description + strlen(description);
64ed39dd EB	152	sprintf(dp, ";uid=0x%x",
64ed39dd EB	153	from_kuid_munged(&init_user_ns, sesInfo->linux_uid));
9eae8a89	154
3e4b3e1f	155	dp = description + strlen(description);
64ed39dd EB	156	sprintf(dp, ";creduid=0x%x",
64ed39dd EB	157	from_kuid_munged(&init_user_ns, sesInfo->cred_uid));
3e4b3e1f	158
04febabc JL	159	if (sesInfo->user_name) {
	160	dp = description + strlen(description);
	161	sprintf(dp, ";user=%s", sesInfo->user_name);
	162	}
e4058245	163
c4c1bff6 JL	164	dp = description + strlen(description);
	165	sprintf(dp, ";pid=0x%x", current->pid);
	166
b6b38f70	167	cFYI(1, "key description = %s", description);
f1d662a7 SF	168	spnego_key = request_key(&cifs_spnego_key_type, description, "");
f1d662a7 SF	169
05b3de63	170	#ifdef CONFIG_CIFS_DEBUG2
f1d662a7 SF	171	if (cifsFYI && !IS_ERR(spnego_key)) {
f1d662a7 SF	172	struct cifs_spnego_msg *msg = spnego_key->payload.data;
ead03e30	173	cifs_dump_mem("SPNEGO reply blob:", msg->data, min(1024U,
05b3de63	174	msg->secblob_len + msg->sesskey_len));
f1d662a7	175	}
05b3de63	176	#endif /* CONFIG_CIFS_DEBUG2 */
f1d662a7 SF	177
	178	out:
	179	kfree(description);
	180	return spnego_key;
	181	}