linux/net/rxrpc/ar-key.c
Nathaniel W Filardo fde0133b9c af_rxrpc: Fix XDR length check in rxrpc key demarshalling.
There may be padding on the ticket contained in the key payload, so just ensure
that the claimed token length is large enough, rather than exactly the right
size.

Signed-off-by: Nathaniel Wesley Filardo <nwf@cs.jhu.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-16 15:24:47 -04:00

1221 lines
28 KiB
C

/* RxRPC key management
*
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* RxRPC keys should have a description of describing their purpose:
* "afs@CAMBRIDGE.REDHAT.COM>
*/
#include <linux/module.h>
#include <linux/net.h>
#include <linux/skbuff.h>
#include <linux/key-type.h>
#include <linux/crypto.h>
#include <linux/ctype.h>
#include <linux/slab.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include <keys/rxrpc-type.h>
#include <keys/user-type.h>
#include "ar-internal.h"
static int rxrpc_vet_description_s(const char *);
static int rxrpc_instantiate(struct key *, struct key_preparsed_payload *);
static int rxrpc_instantiate_s(struct key *, struct key_preparsed_payload *);
static void rxrpc_destroy(struct key *);
static void rxrpc_destroy_s(struct key *);
static void rxrpc_describe(const struct key *, struct seq_file *);
static long rxrpc_read(const struct key *, char __user *, size_t);
/*
* rxrpc defined keys take an arbitrary string as the description and an
* arbitrary blob of data as the payload
*/
struct key_type key_type_rxrpc = {
.name = "rxrpc",
.instantiate = rxrpc_instantiate,
.match = user_match,
.destroy = rxrpc_destroy,
.describe = rxrpc_describe,
.read = rxrpc_read,
};
EXPORT_SYMBOL(key_type_rxrpc);
/*
* rxrpc server defined keys take "<serviceId>:<securityIndex>" as the
* description and an 8-byte decryption key as the payload
*/
struct key_type key_type_rxrpc_s = {
.name = "rxrpc_s",
.vet_description = rxrpc_vet_description_s,
.instantiate = rxrpc_instantiate_s,
.match = user_match,
.destroy = rxrpc_destroy_s,
.describe = rxrpc_describe,
};
/*
* Vet the description for an RxRPC server key
*/
static int rxrpc_vet_description_s(const char *desc)
{
unsigned long num;
char *p;
num = simple_strtoul(desc, &p, 10);
if (*p != ':' || num > 65535)
return -EINVAL;
num = simple_strtoul(p + 1, &p, 10);
if (*p || num < 1 || num > 255)
return -EINVAL;
return 0;
}
/*
* parse an RxKAD type XDR format token
* - the caller guarantees we have at least 4 words
*/
static int rxrpc_instantiate_xdr_rxkad(struct key *key, const __be32 *xdr,
unsigned int toklen)
{
struct rxrpc_key_token *token, **pptoken;
size_t plen;
u32 tktlen;
int ret;
_enter(",{%x,%x,%x,%x},%u",
ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
toklen);
if (toklen <= 8 * 4)
return -EKEYREJECTED;
tktlen = ntohl(xdr[7]);
_debug("tktlen: %x", tktlen);
if (tktlen > AFSTOKEN_RK_TIX_MAX)
return -EKEYREJECTED;
if (toklen < 8 * 4 + tktlen)
return -EKEYREJECTED;
plen = sizeof(*token) + sizeof(*token->kad) + tktlen;
ret = key_payload_reserve(key, key->datalen + plen);
if (ret < 0)
return ret;
plen -= sizeof(*token);
token = kzalloc(sizeof(*token), GFP_KERNEL);
if (!token)
return -ENOMEM;
token->kad = kzalloc(plen, GFP_KERNEL);
if (!token->kad) {
kfree(token);
return -ENOMEM;
}
token->security_index = RXRPC_SECURITY_RXKAD;
token->kad->ticket_len = tktlen;
token->kad->vice_id = ntohl(xdr[0]);
token->kad->kvno = ntohl(xdr[1]);
token->kad->start = ntohl(xdr[4]);
token->kad->expiry = ntohl(xdr[5]);
token->kad->primary_flag = ntohl(xdr[6]);
memcpy(&token->kad->session_key, &xdr[2], 8);
memcpy(&token->kad->ticket, &xdr[8], tktlen);
_debug("SCIX: %u", token->security_index);
_debug("TLEN: %u", token->kad->ticket_len);
_debug("EXPY: %x", token->kad->expiry);
_debug("KVNO: %u", token->kad->kvno);
_debug("PRIM: %u", token->kad->primary_flag);
_debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
token->kad->session_key[0], token->kad->session_key[1],
token->kad->session_key[2], token->kad->session_key[3],
token->kad->session_key[4], token->kad->session_key[5],
token->kad->session_key[6], token->kad->session_key[7]);
if (token->kad->ticket_len >= 8)
_debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
token->kad->ticket[0], token->kad->ticket[1],
token->kad->ticket[2], token->kad->ticket[3],
token->kad->ticket[4], token->kad->ticket[5],
token->kad->ticket[6], token->kad->ticket[7]);
/* count the number of tokens attached */
key->type_data.x[0]++;
/* attach the data */
for (pptoken = (struct rxrpc_key_token **)&key->payload.data;
*pptoken;
pptoken = &(*pptoken)->next)
continue;
*pptoken = token;
if (token->kad->expiry < key->expiry)
key->expiry = token->kad->expiry;
_leave(" = 0");
return 0;
}
static void rxrpc_free_krb5_principal(struct krb5_principal *princ)
{
int loop;
if (princ->name_parts) {
for (loop = princ->n_name_parts - 1; loop >= 0; loop--)
kfree(princ->name_parts[loop]);
kfree(princ->name_parts);
}
kfree(princ->realm);
}
static void rxrpc_free_krb5_tagged(struct krb5_tagged_data *td)
{
kfree(td->data);
}
/*
* free up an RxK5 token
*/
static void rxrpc_rxk5_free(struct rxk5_key *rxk5)
{
int loop;
rxrpc_free_krb5_principal(&rxk5->client);
rxrpc_free_krb5_principal(&rxk5->server);
rxrpc_free_krb5_tagged(&rxk5->session);
if (rxk5->addresses) {
for (loop = rxk5->n_addresses - 1; loop >= 0; loop--)
rxrpc_free_krb5_tagged(&rxk5->addresses[loop]);
kfree(rxk5->addresses);
}
if (rxk5->authdata) {
for (loop = rxk5->n_authdata - 1; loop >= 0; loop--)
rxrpc_free_krb5_tagged(&rxk5->authdata[loop]);
kfree(rxk5->authdata);
}
kfree(rxk5->ticket);
kfree(rxk5->ticket2);
kfree(rxk5);
}
/*
* extract a krb5 principal
*/
static int rxrpc_krb5_decode_principal(struct krb5_principal *princ,
const __be32 **_xdr,
unsigned int *_toklen)
{
const __be32 *xdr = *_xdr;
unsigned int toklen = *_toklen, n_parts, loop, tmp;
/* there must be at least one name, and at least #names+1 length
* words */
if (toklen <= 12)
return -EINVAL;
_enter(",{%x,%x,%x},%u",
ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), toklen);
n_parts = ntohl(*xdr++);
toklen -= 4;
if (n_parts <= 0 || n_parts > AFSTOKEN_K5_COMPONENTS_MAX)
return -EINVAL;
princ->n_name_parts = n_parts;
if (toklen <= (n_parts + 1) * 4)
return -EINVAL;
princ->name_parts = kcalloc(n_parts, sizeof(char *), GFP_KERNEL);
if (!princ->name_parts)
return -ENOMEM;
for (loop = 0; loop < n_parts; loop++) {
if (toklen < 4)
return -EINVAL;
tmp = ntohl(*xdr++);
toklen -= 4;
if (tmp <= 0 || tmp > AFSTOKEN_STRING_MAX)
return -EINVAL;
if (tmp > toklen)
return -EINVAL;
princ->name_parts[loop] = kmalloc(tmp + 1, GFP_KERNEL);
if (!princ->name_parts[loop])
return -ENOMEM;
memcpy(princ->name_parts[loop], xdr, tmp);
princ->name_parts[loop][tmp] = 0;
tmp = (tmp + 3) & ~3;
toklen -= tmp;
xdr += tmp >> 2;
}
if (toklen < 4)
return -EINVAL;
tmp = ntohl(*xdr++);
toklen -= 4;
if (tmp <= 0 || tmp > AFSTOKEN_K5_REALM_MAX)
return -EINVAL;
if (tmp > toklen)
return -EINVAL;
princ->realm = kmalloc(tmp + 1, GFP_KERNEL);
if (!princ->realm)
return -ENOMEM;
memcpy(princ->realm, xdr, tmp);
princ->realm[tmp] = 0;
tmp = (tmp + 3) & ~3;
toklen -= tmp;
xdr += tmp >> 2;
_debug("%s/...@%s", princ->name_parts[0], princ->realm);
*_xdr = xdr;
*_toklen = toklen;
_leave(" = 0 [toklen=%u]", toklen);
return 0;
}
/*
* extract a piece of krb5 tagged data
*/
static int rxrpc_krb5_decode_tagged_data(struct krb5_tagged_data *td,
size_t max_data_size,
const __be32 **_xdr,
unsigned int *_toklen)
{
const __be32 *xdr = *_xdr;
unsigned int toklen = *_toklen, len;
/* there must be at least one tag and one length word */
if (toklen <= 8)
return -EINVAL;
_enter(",%zu,{%x,%x},%u",
max_data_size, ntohl(xdr[0]), ntohl(xdr[1]), toklen);
td->tag = ntohl(*xdr++);
len = ntohl(*xdr++);
toklen -= 8;
if (len > max_data_size)
return -EINVAL;
td->data_len = len;
if (len > 0) {
td->data = kmemdup(xdr, len, GFP_KERNEL);
if (!td->data)
return -ENOMEM;
len = (len + 3) & ~3;
toklen -= len;
xdr += len >> 2;
}
_debug("tag %x len %x", td->tag, td->data_len);
*_xdr = xdr;
*_toklen = toklen;
_leave(" = 0 [toklen=%u]", toklen);
return 0;
}
/*
* extract an array of tagged data
*/
static int rxrpc_krb5_decode_tagged_array(struct krb5_tagged_data **_td,
u8 *_n_elem,
u8 max_n_elem,
size_t max_elem_size,
const __be32 **_xdr,
unsigned int *_toklen)
{
struct krb5_tagged_data *td;
const __be32 *xdr = *_xdr;
unsigned int toklen = *_toklen, n_elem, loop;
int ret;
/* there must be at least one count */
if (toklen < 4)
return -EINVAL;
_enter(",,%u,%zu,{%x},%u",
max_n_elem, max_elem_size, ntohl(xdr[0]), toklen);
n_elem = ntohl(*xdr++);
toklen -= 4;
if (n_elem < 0 || n_elem > max_n_elem)
return -EINVAL;
*_n_elem = n_elem;
if (n_elem > 0) {
if (toklen <= (n_elem + 1) * 4)
return -EINVAL;
_debug("n_elem %d", n_elem);
td = kcalloc(n_elem, sizeof(struct krb5_tagged_data),
GFP_KERNEL);
if (!td)
return -ENOMEM;
*_td = td;
for (loop = 0; loop < n_elem; loop++) {
ret = rxrpc_krb5_decode_tagged_data(&td[loop],
max_elem_size,
&xdr, &toklen);
if (ret < 0)
return ret;
}
}
*_xdr = xdr;
*_toklen = toklen;
_leave(" = 0 [toklen=%u]", toklen);
return 0;
}
/*
* extract a krb5 ticket
*/
static int rxrpc_krb5_decode_ticket(u8 **_ticket, u16 *_tktlen,
const __be32 **_xdr, unsigned int *_toklen)
{
const __be32 *xdr = *_xdr;
unsigned int toklen = *_toklen, len;
/* there must be at least one length word */
if (toklen <= 4)
return -EINVAL;
_enter(",{%x},%u", ntohl(xdr[0]), toklen);
len = ntohl(*xdr++);
toklen -= 4;
if (len > AFSTOKEN_K5_TIX_MAX)
return -EINVAL;
*_tktlen = len;
_debug("ticket len %u", len);
if (len > 0) {
*_ticket = kmemdup(xdr, len, GFP_KERNEL);
if (!*_ticket)
return -ENOMEM;
len = (len + 3) & ~3;
toklen -= len;
xdr += len >> 2;
}
*_xdr = xdr;
*_toklen = toklen;
_leave(" = 0 [toklen=%u]", toklen);
return 0;
}
/*
* parse an RxK5 type XDR format token
* - the caller guarantees we have at least 4 words
*/
static int rxrpc_instantiate_xdr_rxk5(struct key *key, const __be32 *xdr,
unsigned int toklen)
{
struct rxrpc_key_token *token, **pptoken;
struct rxk5_key *rxk5;
const __be32 *end_xdr = xdr + (toklen >> 2);
int ret;
_enter(",{%x,%x,%x,%x},%u",
ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
toklen);
/* reserve some payload space for this subkey - the length of the token
* is a reasonable approximation */
ret = key_payload_reserve(key, key->datalen + toklen);
if (ret < 0)
return ret;
token = kzalloc(sizeof(*token), GFP_KERNEL);
if (!token)
return -ENOMEM;
rxk5 = kzalloc(sizeof(*rxk5), GFP_KERNEL);
if (!rxk5) {
kfree(token);
return -ENOMEM;
}
token->security_index = RXRPC_SECURITY_RXK5;
token->k5 = rxk5;
/* extract the principals */
ret = rxrpc_krb5_decode_principal(&rxk5->client, &xdr, &toklen);
if (ret < 0)
goto error;
ret = rxrpc_krb5_decode_principal(&rxk5->server, &xdr, &toklen);
if (ret < 0)
goto error;
/* extract the session key and the encoding type (the tag field ->
* ENCTYPE_xxx) */
ret = rxrpc_krb5_decode_tagged_data(&rxk5->session, AFSTOKEN_DATA_MAX,
&xdr, &toklen);
if (ret < 0)
goto error;
if (toklen < 4 * 8 + 2 * 4)
goto inval;
rxk5->authtime = be64_to_cpup((const __be64 *) xdr);
xdr += 2;
rxk5->starttime = be64_to_cpup((const __be64 *) xdr);
xdr += 2;
rxk5->endtime = be64_to_cpup((const __be64 *) xdr);
xdr += 2;
rxk5->renew_till = be64_to_cpup((const __be64 *) xdr);
xdr += 2;
rxk5->is_skey = ntohl(*xdr++);
rxk5->flags = ntohl(*xdr++);
toklen -= 4 * 8 + 2 * 4;
_debug("times: a=%llx s=%llx e=%llx rt=%llx",
rxk5->authtime, rxk5->starttime, rxk5->endtime,
rxk5->renew_till);
_debug("is_skey=%x flags=%x", rxk5->is_skey, rxk5->flags);
/* extract the permitted client addresses */
ret = rxrpc_krb5_decode_tagged_array(&rxk5->addresses,
&rxk5->n_addresses,
AFSTOKEN_K5_ADDRESSES_MAX,
AFSTOKEN_DATA_MAX,
&xdr, &toklen);
if (ret < 0)
goto error;
ASSERTCMP((end_xdr - xdr) << 2, ==, toklen);
/* extract the tickets */
ret = rxrpc_krb5_decode_ticket(&rxk5->ticket, &rxk5->ticket_len,
&xdr, &toklen);
if (ret < 0)
goto error;
ret = rxrpc_krb5_decode_ticket(&rxk5->ticket2, &rxk5->ticket2_len,
&xdr, &toklen);
if (ret < 0)
goto error;
ASSERTCMP((end_xdr - xdr) << 2, ==, toklen);
/* extract the typed auth data */
ret = rxrpc_krb5_decode_tagged_array(&rxk5->authdata,
&rxk5->n_authdata,
AFSTOKEN_K5_AUTHDATA_MAX,
AFSTOKEN_BDATALN_MAX,
&xdr, &toklen);
if (ret < 0)
goto error;
ASSERTCMP((end_xdr - xdr) << 2, ==, toklen);
if (toklen != 0)
goto inval;
/* attach the payload to the key */
for (pptoken = (struct rxrpc_key_token **)&key->payload.data;
*pptoken;
pptoken = &(*pptoken)->next)
continue;
*pptoken = token;
if (token->kad->expiry < key->expiry)
key->expiry = token->kad->expiry;
_leave(" = 0");
return 0;
inval:
ret = -EINVAL;
error:
rxrpc_rxk5_free(rxk5);
kfree(token);
_leave(" = %d", ret);
return ret;
}
/*
* attempt to parse the data as the XDR format
* - the caller guarantees we have more than 7 words
*/
static int rxrpc_instantiate_xdr(struct key *key, const void *data, size_t datalen)
{
const __be32 *xdr = data, *token;
const char *cp;
unsigned int len, tmp, loop, ntoken, toklen, sec_ix;
int ret;
_enter(",{%x,%x,%x,%x},%zu",
ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
datalen);
if (datalen > AFSTOKEN_LENGTH_MAX)
goto not_xdr;
/* XDR is an array of __be32's */
if (datalen & 3)
goto not_xdr;
/* the flags should be 0 (the setpag bit must be handled by
* userspace) */
if (ntohl(*xdr++) != 0)
goto not_xdr;
datalen -= 4;
/* check the cell name */
len = ntohl(*xdr++);
if (len < 1 || len > AFSTOKEN_CELL_MAX)
goto not_xdr;
datalen -= 4;
tmp = (len + 3) & ~3;
if (tmp > datalen)
goto not_xdr;
cp = (const char *) xdr;
for (loop = 0; loop < len; loop++)
if (!isprint(cp[loop]))
goto not_xdr;
if (len < tmp)
for (; loop < tmp; loop++)
if (cp[loop])
goto not_xdr;
_debug("cellname: [%u/%u] '%*.*s'",
len, tmp, len, len, (const char *) xdr);
datalen -= tmp;
xdr += tmp >> 2;
/* get the token count */
if (datalen < 12)
goto not_xdr;
ntoken = ntohl(*xdr++);
datalen -= 4;
_debug("ntoken: %x", ntoken);
if (ntoken < 1 || ntoken > AFSTOKEN_MAX)
goto not_xdr;
/* check each token wrapper */
token = xdr;
loop = ntoken;
do {
if (datalen < 8)
goto not_xdr;
toklen = ntohl(*xdr++);
sec_ix = ntohl(*xdr);
datalen -= 4;
_debug("token: [%x/%zx] %x", toklen, datalen, sec_ix);
if (toklen < 20 || toklen > datalen)
goto not_xdr;
datalen -= (toklen + 3) & ~3;
xdr += (toklen + 3) >> 2;
} while (--loop > 0);
_debug("remainder: %zu", datalen);
if (datalen != 0)
goto not_xdr;
/* okay: we're going to assume it's valid XDR format
* - we ignore the cellname, relying on the key to be correctly named
*/
do {
xdr = token;
toklen = ntohl(*xdr++);
token = xdr + ((toklen + 3) >> 2);
sec_ix = ntohl(*xdr++);
toklen -= 4;
_debug("TOKEN type=%u [%p-%p]", sec_ix, xdr, token);
switch (sec_ix) {
case RXRPC_SECURITY_RXKAD:
ret = rxrpc_instantiate_xdr_rxkad(key, xdr, toklen);
if (ret != 0)
goto error;
break;
case RXRPC_SECURITY_RXK5:
ret = rxrpc_instantiate_xdr_rxk5(key, xdr, toklen);
if (ret != 0)
goto error;
break;
default:
ret = -EPROTONOSUPPORT;
goto error;
}
} while (--ntoken > 0);
_leave(" = 0");
return 0;
not_xdr:
_leave(" = -EPROTO");
return -EPROTO;
error:
_leave(" = %d", ret);
return ret;
}
/*
* instantiate an rxrpc defined key
* data should be of the form:
* OFFSET LEN CONTENT
* 0 4 key interface version number
* 4 2 security index (type)
* 6 2 ticket length
* 8 4 key expiry time (time_t)
* 12 4 kvno
* 16 8 session key
* 24 [len] ticket
*
* if no data is provided, then a no-security key is made
*/
static int rxrpc_instantiate(struct key *key, struct key_preparsed_payload *prep)
{
const struct rxrpc_key_data_v1 *v1;
struct rxrpc_key_token *token, **pp;
size_t plen;
u32 kver;
int ret;
_enter("{%x},,%zu", key_serial(key), prep->datalen);
/* handle a no-security key */
if (!prep->data && prep->datalen == 0)
return 0;
/* determine if the XDR payload format is being used */
if (prep->datalen > 7 * 4) {
ret = rxrpc_instantiate_xdr(key, prep->data, prep->datalen);
if (ret != -EPROTO)
return ret;
}
/* get the key interface version number */
ret = -EINVAL;
if (prep->datalen <= 4 || !prep->data)
goto error;
memcpy(&kver, prep->data, sizeof(kver));
prep->data += sizeof(kver);
prep->datalen -= sizeof(kver);
_debug("KEY I/F VERSION: %u", kver);
ret = -EKEYREJECTED;
if (kver != 1)
goto error;
/* deal with a version 1 key */
ret = -EINVAL;
if (prep->datalen < sizeof(*v1))
goto error;
v1 = prep->data;
if (prep->datalen != sizeof(*v1) + v1->ticket_length)
goto error;
_debug("SCIX: %u", v1->security_index);
_debug("TLEN: %u", v1->ticket_length);
_debug("EXPY: %x", v1->expiry);
_debug("KVNO: %u", v1->kvno);
_debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
v1->session_key[0], v1->session_key[1],
v1->session_key[2], v1->session_key[3],
v1->session_key[4], v1->session_key[5],
v1->session_key[6], v1->session_key[7]);
if (v1->ticket_length >= 8)
_debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
v1->ticket[0], v1->ticket[1],
v1->ticket[2], v1->ticket[3],
v1->ticket[4], v1->ticket[5],
v1->ticket[6], v1->ticket[7]);
ret = -EPROTONOSUPPORT;
if (v1->security_index != RXRPC_SECURITY_RXKAD)
goto error;
plen = sizeof(*token->kad) + v1->ticket_length;
ret = key_payload_reserve(key, plen + sizeof(*token));
if (ret < 0)
goto error;
ret = -ENOMEM;
token = kzalloc(sizeof(*token), GFP_KERNEL);
if (!token)
goto error;
token->kad = kzalloc(plen, GFP_KERNEL);
if (!token->kad)
goto error_free;
token->security_index = RXRPC_SECURITY_RXKAD;
token->kad->ticket_len = v1->ticket_length;
token->kad->expiry = v1->expiry;
token->kad->kvno = v1->kvno;
memcpy(&token->kad->session_key, &v1->session_key, 8);
memcpy(&token->kad->ticket, v1->ticket, v1->ticket_length);
/* attach the data */
key->type_data.x[0]++;
pp = (struct rxrpc_key_token **)&key->payload.data;
while (*pp)
pp = &(*pp)->next;
*pp = token;
if (token->kad->expiry < key->expiry)
key->expiry = token->kad->expiry;
token = NULL;
ret = 0;
error_free:
kfree(token);
error:
return ret;
}
/*
* instantiate a server secret key
* data should be a pointer to the 8-byte secret key
*/
static int rxrpc_instantiate_s(struct key *key,
struct key_preparsed_payload *prep)
{
struct crypto_blkcipher *ci;
_enter("{%x},,%zu", key_serial(key), prep->datalen);
if (prep->datalen != 8)
return -EINVAL;
memcpy(&key->type_data, prep->data, 8);
ci = crypto_alloc_blkcipher("pcbc(des)", 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(ci)) {
_leave(" = %ld", PTR_ERR(ci));
return PTR_ERR(ci);
}
if (crypto_blkcipher_setkey(ci, prep->data, 8) < 0)
BUG();
key->payload.data = ci;
_leave(" = 0");
return 0;
}
/*
* dispose of the data dangling from the corpse of a rxrpc key
*/
static void rxrpc_destroy(struct key *key)
{
struct rxrpc_key_token *token;
while ((token = key->payload.data)) {
key->payload.data = token->next;
switch (token->security_index) {
case RXRPC_SECURITY_RXKAD:
kfree(token->kad);
break;
case RXRPC_SECURITY_RXK5:
if (token->k5)
rxrpc_rxk5_free(token->k5);
break;
default:
printk(KERN_ERR "Unknown token type %x on rxrpc key\n",
token->security_index);
BUG();
}
kfree(token);
}
}
/*
* dispose of the data dangling from the corpse of a rxrpc key
*/
static void rxrpc_destroy_s(struct key *key)
{
if (key->payload.data) {
crypto_free_blkcipher(key->payload.data);
key->payload.data = NULL;
}
}
/*
* describe the rxrpc key
*/
static void rxrpc_describe(const struct key *key, struct seq_file *m)
{
seq_puts(m, key->description);
}
/*
* grab the security key for a socket
*/
int rxrpc_request_key(struct rxrpc_sock *rx, char __user *optval, int optlen)
{
struct key *key;
char *description;
_enter("");
if (optlen <= 0 || optlen > PAGE_SIZE - 1)
return -EINVAL;
description = kmalloc(optlen + 1, GFP_KERNEL);
if (!description)
return -ENOMEM;
if (copy_from_user(description, optval, optlen)) {
kfree(description);
return -EFAULT;
}
description[optlen] = 0;
key = request_key(&key_type_rxrpc, description, NULL);
if (IS_ERR(key)) {
kfree(description);
_leave(" = %ld", PTR_ERR(key));
return PTR_ERR(key);
}
rx->key = key;
kfree(description);
_leave(" = 0 [key %x]", key->serial);
return 0;
}
/*
* grab the security keyring for a server socket
*/
int rxrpc_server_keyring(struct rxrpc_sock *rx, char __user *optval,
int optlen)
{
struct key *key;
char *description;
_enter("");
if (optlen <= 0 || optlen > PAGE_SIZE - 1)
return -EINVAL;
description = kmalloc(optlen + 1, GFP_KERNEL);
if (!description)
return -ENOMEM;
if (copy_from_user(description, optval, optlen)) {
kfree(description);
return -EFAULT;
}
description[optlen] = 0;
key = request_key(&key_type_keyring, description, NULL);
if (IS_ERR(key)) {
kfree(description);
_leave(" = %ld", PTR_ERR(key));
return PTR_ERR(key);
}
rx->securities = key;
kfree(description);
_leave(" = 0 [key %x]", key->serial);
return 0;
}
/*
* generate a server data key
*/
int rxrpc_get_server_data_key(struct rxrpc_connection *conn,
const void *session_key,
time_t expiry,
u32 kvno)
{
const struct cred *cred = current_cred();
struct key *key;
int ret;
struct {
u32 kver;
struct rxrpc_key_data_v1 v1;
} data;
_enter("");
key = key_alloc(&key_type_rxrpc, "x",
GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, 0,
KEY_ALLOC_NOT_IN_QUOTA);
if (IS_ERR(key)) {
_leave(" = -ENOMEM [alloc %ld]", PTR_ERR(key));
return -ENOMEM;
}
_debug("key %d", key_serial(key));
data.kver = 1;
data.v1.security_index = RXRPC_SECURITY_RXKAD;
data.v1.ticket_length = 0;
data.v1.expiry = expiry;
data.v1.kvno = 0;
memcpy(&data.v1.session_key, session_key, sizeof(data.v1.session_key));
ret = key_instantiate_and_link(key, &data, sizeof(data), NULL, NULL);
if (ret < 0)
goto error;
conn->key = key;
_leave(" = 0 [%d]", key_serial(key));
return 0;
error:
key_revoke(key);
key_put(key);
_leave(" = -ENOMEM [ins %d]", ret);
return -ENOMEM;
}
EXPORT_SYMBOL(rxrpc_get_server_data_key);
/**
* rxrpc_get_null_key - Generate a null RxRPC key
* @keyname: The name to give the key.
*
* Generate a null RxRPC key that can be used to indicate anonymous security is
* required for a particular domain.
*/
struct key *rxrpc_get_null_key(const char *keyname)
{
const struct cred *cred = current_cred();
struct key *key;
int ret;
key = key_alloc(&key_type_rxrpc, keyname,
GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
KEY_POS_SEARCH, KEY_ALLOC_NOT_IN_QUOTA);
if (IS_ERR(key))
return key;
ret = key_instantiate_and_link(key, NULL, 0, NULL, NULL);
if (ret < 0) {
key_revoke(key);
key_put(key);
return ERR_PTR(ret);
}
return key;
}
EXPORT_SYMBOL(rxrpc_get_null_key);
/*
* read the contents of an rxrpc key
* - this returns the result in XDR form
*/
static long rxrpc_read(const struct key *key,
char __user *buffer, size_t buflen)
{
const struct rxrpc_key_token *token;
const struct krb5_principal *princ;
size_t size;
__be32 __user *xdr, *oldxdr;
u32 cnlen, toksize, ntoks, tok, zero;
u16 toksizes[AFSTOKEN_MAX];
int loop;
_enter("");
/* we don't know what form we should return non-AFS keys in */
if (memcmp(key->description, "afs@", 4) != 0)
return -EOPNOTSUPP;
cnlen = strlen(key->description + 4);
#define RND(X) (((X) + 3) & ~3)
/* AFS keys we return in XDR form, so we need to work out the size of
* the XDR */
size = 2 * 4; /* flags, cellname len */
size += RND(cnlen); /* cellname */
size += 1 * 4; /* token count */
ntoks = 0;
for (token = key->payload.data; token; token = token->next) {
toksize = 4; /* sec index */
switch (token->security_index) {
case RXRPC_SECURITY_RXKAD:
toksize += 8 * 4; /* viceid, kvno, key*2, begin,
* end, primary, tktlen */
toksize += RND(token->kad->ticket_len);
break;
case RXRPC_SECURITY_RXK5:
princ = &token->k5->client;
toksize += 4 + princ->n_name_parts * 4;
for (loop = 0; loop < princ->n_name_parts; loop++)
toksize += RND(strlen(princ->name_parts[loop]));
toksize += 4 + RND(strlen(princ->realm));
princ = &token->k5->server;
toksize += 4 + princ->n_name_parts * 4;
for (loop = 0; loop < princ->n_name_parts; loop++)
toksize += RND(strlen(princ->name_parts[loop]));
toksize += 4 + RND(strlen(princ->realm));
toksize += 8 + RND(token->k5->session.data_len);
toksize += 4 * 8 + 2 * 4;
toksize += 4 + token->k5->n_addresses * 8;
for (loop = 0; loop < token->k5->n_addresses; loop++)
toksize += RND(token->k5->addresses[loop].data_len);
toksize += 4 + RND(token->k5->ticket_len);
toksize += 4 + RND(token->k5->ticket2_len);
toksize += 4 + token->k5->n_authdata * 8;
for (loop = 0; loop < token->k5->n_authdata; loop++)
toksize += RND(token->k5->authdata[loop].data_len);
break;
default: /* we have a ticket we can't encode */
BUG();
continue;
}
_debug("token[%u]: toksize=%u", ntoks, toksize);
ASSERTCMP(toksize, <=, AFSTOKEN_LENGTH_MAX);
toksizes[ntoks++] = toksize;
size += toksize + 4; /* each token has a length word */
}
#undef RND
if (!buffer || buflen < size)
return size;
xdr = (__be32 __user *) buffer;
zero = 0;
#define ENCODE(x) \
do { \
__be32 y = htonl(x); \
if (put_user(y, xdr++) < 0) \
goto fault; \
} while(0)
#define ENCODE_DATA(l, s) \
do { \
u32 _l = (l); \
ENCODE(l); \
if (copy_to_user(xdr, (s), _l) != 0) \
goto fault; \
if (_l & 3 && \
copy_to_user((u8 *)xdr + _l, &zero, 4 - (_l & 3)) != 0) \
goto fault; \
xdr += (_l + 3) >> 2; \
} while(0)
#define ENCODE64(x) \
do { \
__be64 y = cpu_to_be64(x); \
if (copy_to_user(xdr, &y, 8) != 0) \
goto fault; \
xdr += 8 >> 2; \
} while(0)
#define ENCODE_STR(s) \
do { \
const char *_s = (s); \
ENCODE_DATA(strlen(_s), _s); \
} while(0)
ENCODE(0); /* flags */
ENCODE_DATA(cnlen, key->description + 4); /* cellname */
ENCODE(ntoks);
tok = 0;
for (token = key->payload.data; token; token = token->next) {
toksize = toksizes[tok++];
ENCODE(toksize);
oldxdr = xdr;
ENCODE(token->security_index);
switch (token->security_index) {
case RXRPC_SECURITY_RXKAD:
ENCODE(token->kad->vice_id);
ENCODE(token->kad->kvno);
ENCODE_DATA(8, token->kad->session_key);
ENCODE(token->kad->start);
ENCODE(token->kad->expiry);
ENCODE(token->kad->primary_flag);
ENCODE_DATA(token->kad->ticket_len, token->kad->ticket);
break;
case RXRPC_SECURITY_RXK5:
princ = &token->k5->client;
ENCODE(princ->n_name_parts);
for (loop = 0; loop < princ->n_name_parts; loop++)
ENCODE_STR(princ->name_parts[loop]);
ENCODE_STR(princ->realm);
princ = &token->k5->server;
ENCODE(princ->n_name_parts);
for (loop = 0; loop < princ->n_name_parts; loop++)
ENCODE_STR(princ->name_parts[loop]);
ENCODE_STR(princ->realm);
ENCODE(token->k5->session.tag);
ENCODE_DATA(token->k5->session.data_len,
token->k5->session.data);
ENCODE64(token->k5->authtime);
ENCODE64(token->k5->starttime);
ENCODE64(token->k5->endtime);
ENCODE64(token->k5->renew_till);
ENCODE(token->k5->is_skey);
ENCODE(token->k5->flags);
ENCODE(token->k5->n_addresses);
for (loop = 0; loop < token->k5->n_addresses; loop++) {
ENCODE(token->k5->addresses[loop].tag);
ENCODE_DATA(token->k5->addresses[loop].data_len,
token->k5->addresses[loop].data);
}
ENCODE_DATA(token->k5->ticket_len, token->k5->ticket);
ENCODE_DATA(token->k5->ticket2_len, token->k5->ticket2);
ENCODE(token->k5->n_authdata);
for (loop = 0; loop < token->k5->n_authdata; loop++) {
ENCODE(token->k5->authdata[loop].tag);
ENCODE_DATA(token->k5->authdata[loop].data_len,
token->k5->authdata[loop].data);
}
break;
default:
BUG();
break;
}
ASSERTCMP((unsigned long)xdr - (unsigned long)oldxdr, ==,
toksize);
}
#undef ENCODE_STR
#undef ENCODE_DATA
#undef ENCODE64
#undef ENCODE
ASSERTCMP(tok, ==, ntoks);
ASSERTCMP((char __user *) xdr - buffer, ==, size);
_leave(" = %zu", size);
return size;
fault:
_leave(" = -EFAULT");
return -EFAULT;
}