Google Git Google Git
Sign in
linux/linux/kernel/git/viro/vfs/refs/heads/M5/./net/rxrpc/key.c
blob: e7f6b8823eb6e6c6794ed78e1197c1cf8aab4858 [file] [edit]
/* 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>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <crypto/skcipher.h>
#include <linux/module.h>
#include <linux/net.h>
#include <linux/skbuff.h>
#include <linux/key-type.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_preparse(struct key_preparsed_payload *);
static int rxrpc_preparse_s(struct key_preparsed_payload *);
static void rxrpc_free_preparse(struct key_preparsed_payload *);
static void rxrpc_free_preparse_s(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",
.preparse = rxrpc_preparse,
.free_preparse = rxrpc_free_preparse,
.instantiate = generic_key_instantiate,
.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,
.preparse = rxrpc_preparse_s,
.free_preparse = rxrpc_free_preparse_s,
.instantiate = generic_key_instantiate,
.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_preparse_xdr_rxkad(struct key_preparsed_payload *prep,
size_t datalen,
const __be32 *xdr, unsigned int toklen)
{
struct rxrpc_key_token *token, **pptoken;
time64_t expiry;
size_t plen;
u32 tktlen;
_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;
prep->quotalen = datalen + plen;
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 */
prep->payload.data[1] = (void *)((unsigned long)prep->payload.data[1] + 1);
/* attach the data */
for (pptoken = (struct rxrpc_key_token **)&prep->payload.data[0];
*pptoken;
pptoken = &(*pptoken)->next)
continue;
*pptoken = token;
expiry = rxrpc_u32_to_time64(token->kad->expiry);
if (expiry < prep->expiry)
prep->expiry = 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, paddedlen;
/* 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;
paddedlen = (tmp + 3) & ~3;
if (paddedlen > 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;
toklen -= paddedlen;
xdr += paddedlen >> 2;
}
if (toklen < 4)
return -EINVAL;
tmp = ntohl(*xdr++);
toklen -= 4;
if (tmp <= 0 || tmp > AFSTOKEN_K5_REALM_MAX)
return -EINVAL;
paddedlen = (tmp + 3) & ~3;
if (paddedlen > toklen)
return -EINVAL;
princ->realm = kmalloc(tmp + 1, GFP_KERNEL);
if (!princ->realm)
return -ENOMEM;
memcpy(princ->realm, xdr, tmp);
princ->realm[tmp] = 0;
toklen -= paddedlen;
xdr += paddedlen >> 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, paddedlen;
/* 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;
paddedlen = (len + 3) & ~3;
if (paddedlen > toklen)
return -EINVAL;
td->data_len = len;
if (len > 0) {
td->data = kmemdup(xdr, len, GFP_KERNEL);
if (!td->data)
return -ENOMEM;
toklen -= paddedlen;
xdr += paddedlen >> 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 > 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, paddedlen;
/* 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;
paddedlen = (len + 3) & ~3;
if (paddedlen > toklen)
return -EINVAL;
*_tktlen = len;
_debug("ticket len %u", len);
if (len > 0) {
*_ticket = kmemdup(xdr, len, GFP_KERNEL);
if (!*_ticket)
return -ENOMEM;
toklen -= paddedlen;
xdr += paddedlen >> 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_preparse_xdr_rxk5(struct key_preparsed_payload *prep,
size_t datalen,
const __be32 *xdr, unsigned int toklen)
{
struct rxrpc_key_token *token, **pptoken;
struct rxk5_key *rxk5;
const __be32 *end_xdr = xdr + (toklen >> 2);
time64_t expiry;
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 */
prep->quotalen = datalen + toklen;
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 */
for (pptoken = (struct rxrpc_key_token **)&prep->payload.data[0];
*pptoken;
pptoken = &(*pptoken)->next)
continue;
*pptoken = token;
expiry = rxrpc_u32_to_time64(token->k5->endtime);
if (expiry < prep->expiry)
prep->expiry = 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_preparse_xdr(struct key_preparsed_payload *prep)
{
const __be32 *xdr = prep->data, *token;
const char *cp;
unsigned int len, paddedlen, loop, ntoken, toklen, sec_ix;
size_t datalen = prep->datalen;
int ret;
_enter(",{%x,%x,%x,%x},%zu",
ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
prep->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;
paddedlen = (len + 3) & ~3;
if (paddedlen > datalen)
goto not_xdr;
cp = (const char *) xdr;
for (loop = 0; loop < len; loop++)
if (!isprint(cp[loop]))
goto not_xdr;
for (; loop < paddedlen; loop++)
if (cp[loop])
goto not_xdr;
_debug("cellname: [%u/%u] '%*.*s'",
len, paddedlen, len, len, (const char *) xdr);
datalen -= paddedlen;
xdr += paddedlen >> 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);
paddedlen = (toklen + 3) & ~3;
if (toklen < 20 || toklen > datalen || paddedlen > datalen)
goto not_xdr;
datalen -= paddedlen;
xdr += paddedlen >> 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_preparse_xdr_rxkad(prep, datalen, xdr, toklen);
if (ret != 0)
goto error;
break;
case RXRPC_SECURITY_RXK5:
ret = rxrpc_preparse_xdr_rxk5(prep, datalen, 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;
}
/*
* Preparse 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_preparse(struct key_preparsed_payload *prep)
{
const struct rxrpc_key_data_v1 *v1;
struct rxrpc_key_token *token, **pp;
time64_t expiry;
size_t plen;
u32 kver;
int ret;
_enter("%zu", 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_preparse_xdr(prep);
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;
prep->quotalen = plen + sizeof(*token);
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);
/* count the number of tokens attached */
prep->payload.data[1] = (void *)((unsigned long)prep->payload.data[1] + 1);
/* attach the data */
pp = (struct rxrpc_key_token **)&prep->payload.data[0];
while (*pp)
pp = &(*pp)->next;
*pp = token;
expiry = rxrpc_u32_to_time64(token->kad->expiry);
if (expiry < prep->expiry)
prep->expiry = expiry;
token = NULL;
ret = 0;
error_free:
kfree(token);
error:
return ret;
}
/*
* Free token list.
*/
static void rxrpc_free_token_list(struct rxrpc_key_token *token)
{
struct rxrpc_key_token *next;
for (; token; token = next) {
next = 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:
pr_err("Unknown token type %x on rxrpc key\n",
token->security_index);
BUG();
}
kfree(token);
}
}
/*
* Clean up preparse data.
*/
static void rxrpc_free_preparse(struct key_preparsed_payload *prep)
{
rxrpc_free_token_list(prep->payload.data[0]);
}
/*
* Preparse a server secret key.
*
* The data should be the 8-byte secret key.
*/
static int rxrpc_preparse_s(struct key_preparsed_payload *prep)
{
struct crypto_skcipher *ci;
_enter("%zu", prep->datalen);
if (prep->datalen != 8)
return -EINVAL;
memcpy(&prep->payload.data[2], prep->data, 8);
ci = crypto_alloc_skcipher("pcbc(des)", 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(ci)) {
_leave(" = %ld", PTR_ERR(ci));
return PTR_ERR(ci);
}
if (crypto_skcipher_setkey(ci, prep->data, 8) < 0)
BUG();
prep->payload.data[0] = ci;
_leave(" = 0");
return 0;
}
/*
* Clean up preparse data.
*/
static void rxrpc_free_preparse_s(struct key_preparsed_payload *prep)
{
if (prep->payload.data[0])
crypto_free_skcipher(prep->payload.data[0]);
}
/*
* dispose of the data dangling from the corpse of a rxrpc key
*/
static void rxrpc_destroy(struct key *key)
{
rxrpc_free_token_list(key->payload.data[0]);
}
/*
* dispose of the data dangling from the corpse of a rxrpc key
*/
static void rxrpc_destroy_s(struct key *key)
{
if (key->payload.data[0]) {
crypto_free_skcipher(key->payload.data[0]);
key->payload.data[0] = 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 = memdup_user_nul(optval, optlen);
if (IS_ERR(description))
return PTR_ERR(description);
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 = memdup_user_nul(optval, optlen);
if (IS_ERR(description))
return PTR_ERR(description);
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,
time64_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, NULL);
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 = rxrpc_time64_to_u32(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->params.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, NULL);
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[0]; token; token = token->next) {
toksize = 4; /* sec index */
switch (token->security_index) {
case RXRPC_SECURITY_RXKAD:
toksize += 9 * 4; /* viceid, kvno, key*2 + len, 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 __user *)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[0]; 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;
}