Skip to content

Commit

Permalink
cifs: secmech: use shash_desc directly, remove sdesc
Browse files Browse the repository at this point in the history 
The struct sdesc is just a wrapper around shash_desc, with exact same
memory layout. Replace the hashing TFMs with shash_desc as it's what's
passed to the crypto API anyway.

Also remove the crypto_shash pointers as they can be accessed via
shash_desc->tfm (and are actually only used in the setkey calls).

Adapt cifs_{alloc,free}_hash functions to this change.

Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
  • Loading branch information
Enzo Matsumiya authored and Steve French committed Oct 8, 2022
1 parent 8698baa commit 1f3d547
Show file tree
Hide file tree
Showing 7 changed files with 98 additions and 166 deletions.
86 changes: 26 additions & 60 deletions fs/cifs/cifsencrypt.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -103,26 +103,24 @@ static int cifs_calc_signature(struct smb_rqst *rqst,
if (!rqst->rq_iov || !signature || !server)
return -EINVAL;

rc = cifs_alloc_hash("md5", &server->secmech.md5,
&server->secmech.sdescmd5);
rc = cifs_alloc_hash("md5", &server->secmech.md5);
if (rc)
return -1;

rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
rc = crypto_shash_init(server->secmech.md5);
if (rc) {
cifs_dbg(VFS, "%s: Could not init md5\n", __func__);
return rc;
}

rc = crypto_shash_update(&server->secmech.sdescmd5->shash,
rc = crypto_shash_update(server->secmech.md5,
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);
return __cifs_calc_signature(rqst, server, signature, server->secmech.md5);
}

/* must be called with server->srv_mutex held */
Expand Down Expand Up @@ -412,22 +410,22 @@ static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
wchar_t *domain;
wchar_t *server;

if (!ses->server->secmech.sdeschmacmd5) {
if (!ses->server->secmech.hmacmd5) {
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,
rc = crypto_shash_setkey(ses->server->secmech.hmacmd5->tfm, 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);
rc = crypto_shash_init(ses->server->secmech.hmacmd5);
if (rc) {
cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
return rc;
Expand All @@ -448,7 +446,7 @@ static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
memset(user, '\0', 2);
}

rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
rc = crypto_shash_update(ses->server->secmech.hmacmd5,
(char *)user, 2 * len);
kfree(user);
if (rc) {
Expand All @@ -468,7 +466,7 @@ static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
len = cifs_strtoUTF16((__le16 *)domain, ses->domainName, len,
nls_cp);
rc =
crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
crypto_shash_update(ses->server->secmech.hmacmd5,
(char *)domain, 2 * len);
kfree(domain);
if (rc) {
Expand All @@ -488,7 +486,7 @@ static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
len = cifs_strtoUTF16((__le16 *)server, ses->ip_addr, len,
nls_cp);
rc =
crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
crypto_shash_update(ses->server->secmech.hmacmd5,
(char *)server, 2 * len);
kfree(server);
if (rc) {
Expand All @@ -498,7 +496,7 @@ static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
}
}

rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
rc = crypto_shash_final(ses->server->secmech.hmacmd5,
ntlmv2_hash);
if (rc)
cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
Expand All @@ -518,20 +516,20 @@ CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
hash_len = ses->auth_key.len - (CIFS_SESS_KEY_SIZE +
offsetof(struct ntlmv2_resp, challenge.key[0]));

if (!ses->server->secmech.sdeschmacmd5) {
if (!ses->server->secmech.hmacmd5) {
cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
return -1;
}

rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
rc = crypto_shash_setkey(ses->server->secmech.hmacmd5->tfm,
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);
rc = crypto_shash_init(ses->server->secmech.hmacmd5);
if (rc) {
cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
return rc;
Expand All @@ -543,15 +541,15 @@ CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
else
memcpy(ntlmv2->challenge.key,
ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
rc = crypto_shash_update(ses->server->secmech.hmacmd5,
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,
rc = crypto_shash_final(ses->server->secmech.hmacmd5,
ntlmv2->ntlmv2_hash);
if (rc)
cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
Expand Down Expand Up @@ -627,9 +625,7 @@ setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)

cifs_server_lock(ses->server);

rc = cifs_alloc_hash("hmac(md5)",
&ses->server->secmech.hmacmd5,
&ses->server->secmech.sdeschmacmd5);
rc = cifs_alloc_hash("hmac(md5)", &ses->server->secmech.hmacmd5);
if (rc) {
goto unlock;
}
Expand All @@ -649,29 +645,29 @@ setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
}

/* now calculate the session key for NTLMv2 */
rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
rc = crypto_shash_setkey(ses->server->secmech.hmacmd5->tfm,
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);
rc = crypto_shash_init(ses->server->secmech.hmacmd5);
if (rc) {
cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
goto unlock;
}

rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
rc = crypto_shash_update(ses->server->secmech.hmacmd5,
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,
rc = crypto_shash_final(ses->server->secmech.hmacmd5,
ses->auth_key.response);
if (rc)
cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
Expand Down Expand Up @@ -718,30 +714,11 @@ calc_seckey(struct cifs_ses *ses)
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;
}
cifs_free_hash(&server->secmech.aes_cmac);
cifs_free_hash(&server->secmech.hmacsha256);
cifs_free_hash(&server->secmech.md5);
cifs_free_hash(&server->secmech.sha512);
cifs_free_hash(&server->secmech.hmacmd5);

if (server->secmech.enc) {
crypto_free_aead(server->secmech.enc);
Expand All @@ -752,15 +729,4 @@ cifs_crypto_secmech_release(struct TCP_Server_Info *server)
crypto_free_aead(server->secmech.dec);
server->secmech.dec = NULL;
}

kfree_sensitive(server->secmech.sdesccmacaes);
server->secmech.sdesccmacaes = NULL;
kfree_sensitive(server->secmech.sdeschmacsha256);
server->secmech.sdeschmacsha256 = NULL;
kfree_sensitive(server->secmech.sdeschmacmd5);
server->secmech.sdeschmacmd5 = NULL;
kfree_sensitive(server->secmech.sdescmd5);
server->secmech.sdescmd5 = NULL;
kfree_sensitive(server->secmech.sdescsha512);
server->secmech.sdescsha512 = NULL;
}
26 changes: 8 additions & 18 deletions fs/cifs/cifsglob.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -153,26 +153,16 @@ struct session_key {
char *response;
};

/* crypto security descriptor definition */
struct sdesc {
struct shash_desc shash;
char ctx[];
};

/* crypto hashing related structure/fields, not specific to a sec mech */
struct cifs_secmech {
struct crypto_shash *hmacmd5; /* hmac-md5 hash function */
struct crypto_shash *md5; /* md5 hash function */
struct crypto_shash *hmacsha256; /* hmac-sha256 hash function */
struct crypto_shash *cmacaes; /* block-cipher based MAC function */
struct crypto_shash *sha512; /* sha512 hash function */
struct sdesc *sdeschmacmd5; /* ctxt to generate ntlmv2 hash, CR1 */
struct sdesc *sdescmd5; /* ctxt to generate cifs/smb signature */
struct sdesc *sdeschmacsha256; /* ctxt to generate smb2 signature */
struct sdesc *sdesccmacaes; /* ctxt to generate smb3 signature */
struct sdesc *sdescsha512; /* ctxt to generate smb3.11 signing key */
struct crypto_aead *enc; /* smb3 AEAD encryption TFM (AES-CCM and AES-GCM) */
struct crypto_aead *dec; /* smb3 AEAD decryption TFM (AES-CCM and AES-GCM) */
struct shash_desc *hmacmd5; /* hmacmd5 hash function, for NTLMv2/CR1 hashes */
struct shash_desc *md5; /* md5 hash function, for CIFS/SMB1 signatures */
struct shash_desc *hmacsha256; /* hmac-sha256 hash function, for SMB2 signatures */
struct shash_desc *sha512; /* sha512 hash function, for SMB3.1.1 preauth hash */
struct shash_desc *aes_cmac; /* block-cipher based MAC function, for SMB3 signatures */

struct crypto_aead *enc; /* smb3 encryption AEAD TFM (AES-CCM and AES-GCM) */
struct crypto_aead *dec; /* smb3 decryption AEAD TFM (AES-CCM and AES-GCM) */
};

/* per smb session structure/fields */
Expand Down
5 changes: 2 additions & 3 deletions fs/cifs/cifsproto.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -598,9 +598,8 @@ struct cifs_aio_ctx *cifs_aio_ctx_alloc(void);
void cifs_aio_ctx_release(struct kref *refcount);
int setup_aio_ctx_iter(struct cifs_aio_ctx *ctx, struct iov_iter *iter, int rw);

int cifs_alloc_hash(const char *name, struct crypto_shash **shash,
struct sdesc **sdesc);
void cifs_free_hash(struct crypto_shash **shash, struct sdesc **sdesc);
int cifs_alloc_hash(const char *name, struct shash_desc **sdesc);
void cifs_free_hash(struct shash_desc **sdesc);

extern void rqst_page_get_length(struct smb_rqst *rqst, unsigned int page,
unsigned int *len, unsigned int *offset);
Expand Down
13 changes: 6 additions & 7 deletions fs/cifs/link.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -38,29 +38,28 @@ static int
symlink_hash(unsigned int link_len, const char *link_str, u8 *md5_hash)
{
int rc;
struct crypto_shash *md5 = NULL;
struct sdesc *sdescmd5 = NULL;
struct shash_desc *md5 = NULL;

rc = cifs_alloc_hash("md5", &md5, &sdescmd5);
rc = cifs_alloc_hash("md5", &md5);
if (rc)
goto symlink_hash_err;

rc = crypto_shash_init(&sdescmd5->shash);
rc = crypto_shash_init(md5);
if (rc) {
cifs_dbg(VFS, "%s: Could not init md5 shash\n", __func__);
goto symlink_hash_err;
}
rc = crypto_shash_update(&sdescmd5->shash, link_str, link_len);
rc = crypto_shash_update(md5, link_str, link_len);
if (rc) {
cifs_dbg(VFS, "%s: Could not update with link_str\n", __func__);
goto symlink_hash_err;
}
rc = crypto_shash_final(&sdescmd5->shash, md5_hash);
rc = crypto_shash_final(md5, md5_hash);
if (rc)
cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);

symlink_hash_err:
cifs_free_hash(&md5, &sdescmd5);
cifs_free_hash(&md5);
return rc;
}

Expand Down
49 changes: 24 additions & 25 deletions fs/cifs/misc.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1071,59 +1071,58 @@ setup_aio_ctx_iter(struct cifs_aio_ctx *ctx, struct iov_iter *iter, int rw)
/**
* cifs_alloc_hash - allocate hash and hash context together
* @name: The name of the crypto hash algo
* @shash: Where to put the pointer to the hash algo
* @sdesc: Where to put the pointer to the hash descriptor
* @sdesc: SHASH descriptor where to put the pointer to the hash TFM
*
* The caller has to make sure @sdesc is initialized to either NULL or
* a valid context. Both can be freed via cifs_free_hash().
* a valid context. It can be freed via cifs_free_hash().
*/
int
cifs_alloc_hash(const char *name,
struct crypto_shash **shash, struct sdesc **sdesc)
cifs_alloc_hash(const char *name, struct shash_desc **sdesc)
{
int rc = 0;
size_t size;
struct crypto_shash *alg = NULL;

if (*sdesc != NULL)
if (*sdesc)
return 0;

*shash = crypto_alloc_shash(name, 0, 0);
if (IS_ERR(*shash)) {
cifs_dbg(VFS, "Could not allocate crypto %s\n", name);
rc = PTR_ERR(*shash);
*shash = NULL;
alg = crypto_alloc_shash(name, 0, 0);
if (IS_ERR(alg)) {
cifs_dbg(VFS, "Could not allocate shash TFM '%s'\n", name);
rc = PTR_ERR(alg);
*sdesc = NULL;
return rc;
}

size = sizeof(struct shash_desc) + crypto_shash_descsize(*shash);
*sdesc = kmalloc(size, GFP_KERNEL);
*sdesc = kmalloc(sizeof(struct shash_desc) + crypto_shash_descsize(alg), GFP_KERNEL);
if (*sdesc == NULL) {
cifs_dbg(VFS, "no memory left to allocate crypto %s\n", name);
crypto_free_shash(*shash);
*shash = NULL;
cifs_dbg(VFS, "no memory left to allocate shash TFM '%s'\n", name);
crypto_free_shash(alg);
return -ENOMEM;
}

(*sdesc)->shash.tfm = *shash;
(*sdesc)->tfm = alg;
return 0;
}

/**
* cifs_free_hash - free hash and hash context together
* @shash: Where to find the pointer to the hash algo
* @sdesc: Where to find the pointer to the hash descriptor
* @sdesc: Where to find the pointer to the hash TFM
*
* Freeing a NULL hash or context is safe.
* Freeing a NULL descriptor is safe.
*/
void
cifs_free_hash(struct crypto_shash **shash, struct sdesc **sdesc)
cifs_free_hash(struct shash_desc **sdesc)
{
if (unlikely(!sdesc) || !*sdesc)
return;

if ((*sdesc)->tfm) {
crypto_free_shash((*sdesc)->tfm);
(*sdesc)->tfm = NULL;
}

kfree_sensitive(*sdesc);
*sdesc = NULL;
if (*shash)
crypto_free_shash(*shash);
*shash = NULL;
}

/**
Expand Down
Loading

0 comments on commit 1f3d547

Please sign in to comment.