linux/fs/cifs/cifsencrypt.c
Vincent Whitchurch cc391b694f cifs: fix potential deadlock in direct reclaim
The srv_mutex is used during writeback so cifs should ensure that
allocations done when that mutex is held are done with GFP_NOFS, to
avoid having direct reclaim ending up waiting for the same mutex and
causing a deadlock.  This is detected by lockdep with the splat below:

 ======================================================
 WARNING: possible circular locking dependency detected
 5.18.0 #70 Not tainted
 ------------------------------------------------------
 kswapd0/49 is trying to acquire lock:
 ffff8880195782e0 (&tcp_ses->srv_mutex){+.+.}-{3:3}, at: compound_send_recv

 but task is already holding lock:
 ffffffffa98e66c0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #1 (fs_reclaim){+.+.}-{0:0}:
        fs_reclaim_acquire
        kmem_cache_alloc_trace
        __request_module
        crypto_alg_mod_lookup
        crypto_alloc_tfm_node
        crypto_alloc_shash
        cifs_alloc_hash
        smb311_crypto_shash_allocate
        smb311_update_preauth_hash
        compound_send_recv
        cifs_send_recv
        SMB2_negotiate
        smb2_negotiate
        cifs_negotiate_protocol
        cifs_get_smb_ses
        cifs_mount
        cifs_smb3_do_mount
        smb3_get_tree
        vfs_get_tree
        path_mount
        __x64_sys_mount
        do_syscall_64
        entry_SYSCALL_64_after_hwframe

 -> #0 (&tcp_ses->srv_mutex){+.+.}-{3:3}:
        __lock_acquire
        lock_acquire
        __mutex_lock
        mutex_lock_nested
        compound_send_recv
        cifs_send_recv
        SMB2_write
        smb2_sync_write
        cifs_write
        cifs_writepage_locked
        cifs_writepage
        shrink_page_list
        shrink_lruvec
        shrink_node
        balance_pgdat
        kswapd
        kthread
        ret_from_fork

 other info that might help us debug this:

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(fs_reclaim);
                                lock(&tcp_ses->srv_mutex);
                                lock(fs_reclaim);
   lock(&tcp_ses->srv_mutex);

  *** DEADLOCK ***

 1 lock held by kswapd0/49:
  #0: ffffffffa98e66c0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat

 stack backtrace:
 CPU: 2 PID: 49 Comm: kswapd0 Not tainted 5.18.0 #70
 Call Trace:
  <TASK>
  dump_stack_lvl
  dump_stack
  print_circular_bug.cold
  check_noncircular
  __lock_acquire
  lock_acquire
  __mutex_lock
  mutex_lock_nested
  compound_send_recv
  cifs_send_recv
  SMB2_write
  smb2_sync_write
  cifs_write
  cifs_writepage_locked
  cifs_writepage
  shrink_page_list
  shrink_lruvec
  shrink_node
  balance_pgdat
  kswapd
  kthread
  ret_from_fork
  </TASK>

Fix this by using the memalloc_nofs_save/restore APIs around the places
where the srv_mutex is held.  Do this in a wrapper function for the
lock/unlock of the srv_mutex, and rename the srv_mutex to avoid missing
call sites in the conversion.

Note that there is another lockdep warning involving internal crypto
locks, which was masked by this problem and is visible after this fix,
see the discussion in this thread:

 https://lore.kernel.org/all/20220523123755.GA13668@axis.com/

Link: https://lore.kernel.org/r/CANT5p=rqcYfYMVHirqvdnnca4Mo+JQSw5Qu12v=kPfpk5yhhmg@mail.gmail.com/
Reported-by: Shyam Prasad N <nspmangalore@gmail.com>
Suggested-by: Lars Persson <larper@axis.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-06-01 00:03:18 -05:00

768 lines
20 KiB
C

// SPDX-License-Identifier: LGPL-2.1
/*
*
* Encryption and hashing operations relating to NTLM, NTLMv2. See MS-NLMP
* for more detailed information
*
* Copyright (C) International Business Machines Corp., 2005,2013
* Author(s): Steve French (sfrench@us.ibm.com)
*
*/
#include <linux/fs.h>
#include <linux/slab.h>
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifs_debug.h"
#include "cifs_unicode.h"
#include "cifsproto.h"
#include "ntlmssp.h"
#include <linux/ctype.h>
#include <linux/random.h>
#include <linux/highmem.h>
#include <linux/fips.h>
#include "../smbfs_common/arc4.h"
#include <crypto/aead.h>
int __cifs_calc_signature(struct smb_rqst *rqst,
struct TCP_Server_Info *server, char *signature,
struct shash_desc *shash)
{
int i;
int rc;
struct kvec *iov = rqst->rq_iov;
int n_vec = rqst->rq_nvec;
int is_smb2 = server->vals->header_preamble_size == 0;
/* iov[0] is actual data and not the rfc1002 length for SMB2+ */
if (is_smb2) {
if (iov[0].iov_len <= 4)
return -EIO;
i = 0;
} else {
if (n_vec < 2 || iov[0].iov_len != 4)
return -EIO;
i = 1; /* skip rfc1002 length */
}
for (; i < n_vec; i++) {
if (iov[i].iov_len == 0)
continue;
if (iov[i].iov_base == NULL) {
cifs_dbg(VFS, "null iovec entry\n");
return -EIO;
}
rc = crypto_shash_update(shash,
iov[i].iov_base, iov[i].iov_len);
if (rc) {
cifs_dbg(VFS, "%s: Could not update with payload\n",
__func__);
return rc;
}
}
/* now hash over the rq_pages array */
for (i = 0; i < rqst->rq_npages; i++) {
void *kaddr;
unsigned int len, offset;
rqst_page_get_length(rqst, i, &len, &offset);
kaddr = (char *) kmap(rqst->rq_pages[i]) + offset;
rc = crypto_shash_update(shash, kaddr, len);
if (rc) {
cifs_dbg(VFS, "%s: Could not update with payload\n",
__func__);
kunmap(rqst->rq_pages[i]);
return rc;
}
kunmap(rqst->rq_pages[i]);
}
rc = crypto_shash_final(shash, signature);
if (rc)
cifs_dbg(VFS, "%s: Could not generate hash\n", __func__);
return rc;
}
/*
* Calculate and return the CIFS signature based on the mac key and SMB PDU.
* The 16 byte signature must be allocated by the caller. Note we only use the
* 1st eight bytes and that the smb header signature field on input contains
* the sequence number before this function is called. Also, this function
* should be called with the server->srv_mutex held.
*/
static int cifs_calc_signature(struct smb_rqst *rqst,
struct TCP_Server_Info *server, char *signature)
{
int rc;
if (!rqst->rq_iov || !signature || !server)
return -EINVAL;
rc = cifs_alloc_hash("md5", &server->secmech.md5,
&server->secmech.sdescmd5);
if (rc)
return -1;
rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
if (rc) {
cifs_dbg(VFS, "%s: Could not init md5\n", __func__);
return rc;
}
rc = crypto_shash_update(&server->secmech.sdescmd5->shash,
server->session_key.response, server->session_key.len);
if (rc) {
cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
return rc;
}
return __cifs_calc_signature(rqst, server, signature,
&server->secmech.sdescmd5->shash);
}
/* must be called with server->srv_mutex held */
int cifs_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server,
__u32 *pexpected_response_sequence_number)
{
int rc = 0;
char smb_signature[20];
struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
if (rqst->rq_iov[0].iov_len != 4 ||
rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
return -EIO;
if ((cifs_pdu == NULL) || (server == NULL))
return -EINVAL;
spin_lock(&cifs_tcp_ses_lock);
if (!(cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) ||
server->tcpStatus == CifsNeedNegotiate) {
spin_unlock(&cifs_tcp_ses_lock);
return rc;
}
spin_unlock(&cifs_tcp_ses_lock);
if (!server->session_estab) {
memcpy(cifs_pdu->Signature.SecuritySignature, "BSRSPYL", 8);
return rc;
}
cifs_pdu->Signature.Sequence.SequenceNumber =
cpu_to_le32(server->sequence_number);
cifs_pdu->Signature.Sequence.Reserved = 0;
*pexpected_response_sequence_number = ++server->sequence_number;
++server->sequence_number;
rc = cifs_calc_signature(rqst, server, smb_signature);
if (rc)
memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
else
memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
return rc;
}
int cifs_sign_smbv(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
__u32 *pexpected_response_sequence)
{
struct smb_rqst rqst = { .rq_iov = iov,
.rq_nvec = n_vec };
return cifs_sign_rqst(&rqst, server, pexpected_response_sequence);
}
/* must be called with server->srv_mutex held */
int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
__u32 *pexpected_response_sequence_number)
{
struct kvec iov[2];
iov[0].iov_base = cifs_pdu;
iov[0].iov_len = 4;
iov[1].iov_base = (char *)cifs_pdu + 4;
iov[1].iov_len = be32_to_cpu(cifs_pdu->smb_buf_length);
return cifs_sign_smbv(iov, 2, server,
pexpected_response_sequence_number);
}
int cifs_verify_signature(struct smb_rqst *rqst,
struct TCP_Server_Info *server,
__u32 expected_sequence_number)
{
unsigned int rc;
char server_response_sig[8];
char what_we_think_sig_should_be[20];
struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
if (rqst->rq_iov[0].iov_len != 4 ||
rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
return -EIO;
if (cifs_pdu == NULL || server == NULL)
return -EINVAL;
if (!server->session_estab)
return 0;
if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
struct smb_com_lock_req *pSMB =
(struct smb_com_lock_req *)cifs_pdu;
if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
return 0;
}
/* BB what if signatures are supposed to be on for session but
server does not send one? BB */
/* Do not need to verify session setups with signature "BSRSPYL " */
if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0)
cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
cifs_pdu->Command);
/* save off the origiginal signature so we can modify the smb and check
its signature against what the server sent */
memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8);
cifs_pdu->Signature.Sequence.SequenceNumber =
cpu_to_le32(expected_sequence_number);
cifs_pdu->Signature.Sequence.Reserved = 0;
cifs_server_lock(server);
rc = cifs_calc_signature(rqst, server, what_we_think_sig_should_be);
cifs_server_unlock(server);
if (rc)
return rc;
/* cifs_dump_mem("what we think it should be: ",
what_we_think_sig_should_be, 16); */
if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))
return -EACCES;
else
return 0;
}
/* Build a proper attribute value/target info pairs blob.
* Fill in netbios and dns domain name and workstation name
* and client time (total five av pairs and + one end of fields indicator.
* Allocate domain name which gets freed when session struct is deallocated.
*/
static int
build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
{
unsigned int dlen;
unsigned int size = 2 * sizeof(struct ntlmssp2_name);
char *defdmname = "WORKGROUP";
unsigned char *blobptr;
struct ntlmssp2_name *attrptr;
if (!ses->domainName) {
ses->domainName = kstrdup(defdmname, GFP_KERNEL);
if (!ses->domainName)
return -ENOMEM;
}
dlen = strlen(ses->domainName);
/*
* The length of this blob is two times the size of a
* structure (av pair) which holds name/size
* ( for NTLMSSP_AV_NB_DOMAIN_NAME followed by NTLMSSP_AV_EOL ) +
* unicode length of a netbios domain name
*/
ses->auth_key.len = size + 2 * dlen;
ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL);
if (!ses->auth_key.response) {
ses->auth_key.len = 0;
return -ENOMEM;
}
blobptr = ses->auth_key.response;
attrptr = (struct ntlmssp2_name *) blobptr;
/*
* As defined in MS-NTLM 3.3.2, just this av pair field
* is sufficient as part of the temp
*/
attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
attrptr->length = cpu_to_le16(2 * dlen);
blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
cifs_strtoUTF16((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
return 0;
}
/* Server has provided av pairs/target info in the type 2 challenge
* packet and we have plucked it and stored within smb session.
* We parse that blob here to find netbios domain name to be used
* as part of ntlmv2 authentication (in Target String), if not already
* specified on the command line.
* If this function returns without any error but without fetching
* domain name, authentication may fail against some server but
* may not fail against other (those who are not very particular
* about target string i.e. for some, just user name might suffice.
*/
static int
find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
{
unsigned int attrsize;
unsigned int type;
unsigned int onesize = sizeof(struct ntlmssp2_name);
unsigned char *blobptr;
unsigned char *blobend;
struct ntlmssp2_name *attrptr;
if (!ses->auth_key.len || !ses->auth_key.response)
return 0;
blobptr = ses->auth_key.response;
blobend = blobptr + ses->auth_key.len;
while (blobptr + onesize < blobend) {
attrptr = (struct ntlmssp2_name *) blobptr;
type = le16_to_cpu(attrptr->type);
if (type == NTLMSSP_AV_EOL)
break;
blobptr += 2; /* advance attr type */
attrsize = le16_to_cpu(attrptr->length);
blobptr += 2; /* advance attr size */
if (blobptr + attrsize > blobend)
break;
if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
if (!attrsize || attrsize >= CIFS_MAX_DOMAINNAME_LEN)
break;
if (!ses->domainName) {
ses->domainName =
kmalloc(attrsize + 1, GFP_KERNEL);
if (!ses->domainName)
return -ENOMEM;
cifs_from_utf16(ses->domainName,
(__le16 *)blobptr, attrsize, attrsize,
nls_cp, NO_MAP_UNI_RSVD);
break;
}
}
blobptr += attrsize; /* advance attr value */
}
return 0;
}
/* Server has provided av pairs/target info in the type 2 challenge
* packet and we have plucked it and stored within smb session.
* We parse that blob here to find the server given timestamp
* as part of ntlmv2 authentication (or local current time as
* default in case of failure)
*/
static __le64
find_timestamp(struct cifs_ses *ses)
{
unsigned int attrsize;
unsigned int type;
unsigned int onesize = sizeof(struct ntlmssp2_name);
unsigned char *blobptr;
unsigned char *blobend;
struct ntlmssp2_name *attrptr;
struct timespec64 ts;
if (!ses->auth_key.len || !ses->auth_key.response)
return 0;
blobptr = ses->auth_key.response;
blobend = blobptr + ses->auth_key.len;
while (blobptr + onesize < blobend) {
attrptr = (struct ntlmssp2_name *) blobptr;
type = le16_to_cpu(attrptr->type);
if (type == NTLMSSP_AV_EOL)
break;
blobptr += 2; /* advance attr type */
attrsize = le16_to_cpu(attrptr->length);
blobptr += 2; /* advance attr size */
if (blobptr + attrsize > blobend)
break;
if (type == NTLMSSP_AV_TIMESTAMP) {
if (attrsize == sizeof(u64))
return *((__le64 *)blobptr);
}
blobptr += attrsize; /* advance attr value */
}
ktime_get_real_ts64(&ts);
return cpu_to_le64(cifs_UnixTimeToNT(ts));
}
static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
const struct nls_table *nls_cp)
{
int rc = 0;
int len;
char nt_hash[CIFS_NTHASH_SIZE];
__le16 *user;
wchar_t *domain;
wchar_t *server;
if (!ses->server->secmech.sdeschmacmd5) {
cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
return -1;
}
/* calculate md4 hash of password */
E_md4hash(ses->password, nt_hash, nls_cp);
rc = crypto_shash_setkey(ses->server->secmech.hmacmd5, nt_hash,
CIFS_NTHASH_SIZE);
if (rc) {
cifs_dbg(VFS, "%s: Could not set NT Hash as a key\n", __func__);
return rc;
}
rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
if (rc) {
cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
return rc;
}
/* convert ses->user_name to unicode */
len = ses->user_name ? strlen(ses->user_name) : 0;
user = kmalloc(2 + (len * 2), GFP_KERNEL);
if (user == NULL) {
rc = -ENOMEM;
return rc;
}
if (len) {
len = cifs_strtoUTF16(user, ses->user_name, len, nls_cp);
UniStrupr(user);
} else {
memset(user, '\0', 2);
}
rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
(char *)user, 2 * len);
kfree(user);
if (rc) {
cifs_dbg(VFS, "%s: Could not update with user\n", __func__);
return rc;
}
/* convert ses->domainName to unicode and uppercase */
if (ses->domainName) {
len = strlen(ses->domainName);
domain = kmalloc(2 + (len * 2), GFP_KERNEL);
if (domain == NULL) {
rc = -ENOMEM;
return rc;
}
len = cifs_strtoUTF16((__le16 *)domain, ses->domainName, len,
nls_cp);
rc =
crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
(char *)domain, 2 * len);
kfree(domain);
if (rc) {
cifs_dbg(VFS, "%s: Could not update with domain\n",
__func__);
return rc;
}
} else {
/* We use ses->ip_addr if no domain name available */
len = strlen(ses->ip_addr);
server = kmalloc(2 + (len * 2), GFP_KERNEL);
if (server == NULL) {
rc = -ENOMEM;
return rc;
}
len = cifs_strtoUTF16((__le16 *)server, ses->ip_addr, len,
nls_cp);
rc =
crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
(char *)server, 2 * len);
kfree(server);
if (rc) {
cifs_dbg(VFS, "%s: Could not update with server\n",
__func__);
return rc;
}
}
rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
ntlmv2_hash);
if (rc)
cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
return rc;
}
static int
CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
{
int rc;
struct ntlmv2_resp *ntlmv2 = (struct ntlmv2_resp *)
(ses->auth_key.response + CIFS_SESS_KEY_SIZE);
unsigned int hash_len;
/* The MD5 hash starts at challenge_key.key */
hash_len = ses->auth_key.len - (CIFS_SESS_KEY_SIZE +
offsetof(struct ntlmv2_resp, challenge.key[0]));
if (!ses->server->secmech.sdeschmacmd5) {
cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
return -1;
}
rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
if (rc) {
cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
__func__);
return rc;
}
rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
if (rc) {
cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
return rc;
}
if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED)
memcpy(ntlmv2->challenge.key,
ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
else
memcpy(ntlmv2->challenge.key,
ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
ntlmv2->challenge.key, hash_len);
if (rc) {
cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
return rc;
}
/* Note that the MD5 digest over writes anon.challenge_key.key */
rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
ntlmv2->ntlmv2_hash);
if (rc)
cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
return rc;
}
int
setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
{
int rc;
int baselen;
unsigned int tilen;
struct ntlmv2_resp *ntlmv2;
char ntlmv2_hash[16];
unsigned char *tiblob = NULL; /* target info blob */
__le64 rsp_timestamp;
if (nls_cp == NULL) {
cifs_dbg(VFS, "%s called with nls_cp==NULL\n", __func__);
return -EINVAL;
}
if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED) {
if (!ses->domainName) {
if (ses->domainAuto) {
rc = find_domain_name(ses, nls_cp);
if (rc) {
cifs_dbg(VFS, "error %d finding domain name\n",
rc);
goto setup_ntlmv2_rsp_ret;
}
} else {
ses->domainName = kstrdup("", GFP_KERNEL);
}
}
} else {
rc = build_avpair_blob(ses, nls_cp);
if (rc) {
cifs_dbg(VFS, "error %d building av pair blob\n", rc);
goto setup_ntlmv2_rsp_ret;
}
}
/* Must be within 5 minutes of the server (or in range +/-2h
* in case of Mac OS X), so simply carry over server timestamp
* (as Windows 7 does)
*/
rsp_timestamp = find_timestamp(ses);
baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp);
tilen = ses->auth_key.len;
tiblob = ses->auth_key.response;
ses->auth_key.response = kmalloc(baselen + tilen, GFP_KERNEL);
if (!ses->auth_key.response) {
rc = -ENOMEM;
ses->auth_key.len = 0;
goto setup_ntlmv2_rsp_ret;
}
ses->auth_key.len += baselen;
ntlmv2 = (struct ntlmv2_resp *)
(ses->auth_key.response + CIFS_SESS_KEY_SIZE);
ntlmv2->blob_signature = cpu_to_le32(0x00000101);
ntlmv2->reserved = 0;
ntlmv2->time = rsp_timestamp;
get_random_bytes(&ntlmv2->client_chal, sizeof(ntlmv2->client_chal));
ntlmv2->reserved2 = 0;
memcpy(ses->auth_key.response + baselen, tiblob, tilen);
cifs_server_lock(ses->server);
rc = cifs_alloc_hash("hmac(md5)",
&ses->server->secmech.hmacmd5,
&ses->server->secmech.sdeschmacmd5);
if (rc) {
goto unlock;
}
/* calculate ntlmv2_hash */
rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);
if (rc) {
cifs_dbg(VFS, "Could not get v2 hash rc %d\n", rc);
goto unlock;
}
/* calculate first part of the client response (CR1) */
rc = CalcNTLMv2_response(ses, ntlmv2_hash);
if (rc) {
cifs_dbg(VFS, "Could not calculate CR1 rc: %d\n", rc);
goto unlock;
}
/* now calculate the session key for NTLMv2 */
rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
if (rc) {
cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
__func__);
goto unlock;
}
rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
if (rc) {
cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
goto unlock;
}
rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
ntlmv2->ntlmv2_hash,
CIFS_HMAC_MD5_HASH_SIZE);
if (rc) {
cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
goto unlock;
}
rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
ses->auth_key.response);
if (rc)
cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
unlock:
cifs_server_unlock(ses->server);
setup_ntlmv2_rsp_ret:
kfree(tiblob);
return rc;
}
int
calc_seckey(struct cifs_ses *ses)
{
unsigned char sec_key[CIFS_SESS_KEY_SIZE]; /* a nonce */
struct arc4_ctx *ctx_arc4;
if (fips_enabled)
return -ENODEV;
get_random_bytes(sec_key, CIFS_SESS_KEY_SIZE);
ctx_arc4 = kmalloc(sizeof(*ctx_arc4), GFP_KERNEL);
if (!ctx_arc4) {
cifs_dbg(VFS, "Could not allocate arc4 context\n");
return -ENOMEM;
}
cifs_arc4_setkey(ctx_arc4, ses->auth_key.response, CIFS_SESS_KEY_SIZE);
cifs_arc4_crypt(ctx_arc4, ses->ntlmssp->ciphertext, sec_key,
CIFS_CPHTXT_SIZE);
/* make secondary_key/nonce as session key */
memcpy(ses->auth_key.response, sec_key, CIFS_SESS_KEY_SIZE);
/* and make len as that of session key only */
ses->auth_key.len = CIFS_SESS_KEY_SIZE;
memzero_explicit(sec_key, CIFS_SESS_KEY_SIZE);
kfree_sensitive(ctx_arc4);
return 0;
}
void
cifs_crypto_secmech_release(struct TCP_Server_Info *server)
{
if (server->secmech.cmacaes) {
crypto_free_shash(server->secmech.cmacaes);
server->secmech.cmacaes = NULL;
}
if (server->secmech.hmacsha256) {
crypto_free_shash(server->secmech.hmacsha256);
server->secmech.hmacsha256 = NULL;
}
if (server->secmech.md5) {
crypto_free_shash(server->secmech.md5);
server->secmech.md5 = NULL;
}
if (server->secmech.sha512) {
crypto_free_shash(server->secmech.sha512);
server->secmech.sha512 = NULL;
}
if (server->secmech.hmacmd5) {
crypto_free_shash(server->secmech.hmacmd5);
server->secmech.hmacmd5 = NULL;
}
if (server->secmech.ccmaesencrypt) {
crypto_free_aead(server->secmech.ccmaesencrypt);
server->secmech.ccmaesencrypt = NULL;
}
if (server->secmech.ccmaesdecrypt) {
crypto_free_aead(server->secmech.ccmaesdecrypt);
server->secmech.ccmaesdecrypt = NULL;
}
kfree(server->secmech.sdesccmacaes);
server->secmech.sdesccmacaes = NULL;
kfree(server->secmech.sdeschmacsha256);
server->secmech.sdeschmacsha256 = NULL;
kfree(server->secmech.sdeschmacmd5);
server->secmech.sdeschmacmd5 = NULL;
kfree(server->secmech.sdescmd5);
server->secmech.sdescmd5 = NULL;
kfree(server->secmech.sdescsha512);
server->secmech.sdescsha512 = NULL;
}