@@ -2,6 +2,9 @@ config CIFS
tristate "CIFS support (advanced network filesystem, SMBFS successor)"
depends on INET
select NLS
+ select CRYPTO
+ select CRYPTO_MD5
+ select CRYPTO_ARC4
help
This is the client VFS module for the Common Internet File System
(CIFS) protocol which is the successor to the Server Message Block
@@ -477,3 +477,128 @@ void CalcNTLMv2_response(const struct cifsSesInfo *ses,
hmac_md5_final(v2_session_response, &context);
/* cifs_dump_mem("v2_sess_rsp: ", v2_session_response, 32); */
}
+
+int
+calc_seckey(struct TCP_Server_Info *server)
+{
+ int rc;
+ struct crypto_blkcipher *tfm_arc4;
+ struct scatterlist sgin, sgout;
+ struct blkcipher_desc desc;
+
+ if (!server) {
+ cERROR(1, "%s: Can't determine ciphertext key\n", __func__);
+ return 1;
+ }
+
+ mutex_lock(&server->srv_mutex);
+ if (server->cphready) {
+ mutex_unlock(&server->srv_mutex);
+ return 0;
+ }
+
+ get_random_bytes(server->ntlmssp.sec_key, CIFS_NTLMV2_SESSKEY_SIZE);
+
+ tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)",
+ 0, CRYPTO_ALG_ASYNC);
+ if (!tfm_arc4 || IS_ERR(tfm_arc4)) {
+ cERROR(1, "could not allocate crypto API arc4\n");
+ mutex_unlock(&server->srv_mutex);
+ return PTR_ERR(tfm_arc4);
+ }
+
+ desc.tfm = tfm_arc4;
+
+ crypto_blkcipher_setkey(tfm_arc4, server->session_key.data.ntlmv2.key,
+ CIFS_CPHTXT_SIZE);
+
+ sg_init_one(&sgin, server->ntlmssp.sec_key, CIFS_CPHTXT_SIZE);
+ sg_init_one(&sgout, server->ntlmssp.ciphertext, CIFS_CPHTXT_SIZE);
+
+ rc = crypto_blkcipher_encrypt(&desc, &sgout, &sgin, CIFS_CPHTXT_SIZE);
+ if (rc) {
+ cERROR(1, "could not encrypt session key rc: %d\n", rc);
+ crypto_free_blkcipher(tfm_arc4);
+ mutex_unlock(&server->srv_mutex);
+ return rc;
+ }
+
+ crypto_free_blkcipher(tfm_arc4);
+
+ server->sequence_number = 0;
+ server->cphready = true;
+ mutex_unlock(&server->srv_mutex);
+
+ return 0;
+}
+
+void
+cifs_crypto_shash_release(struct TCP_Server_Info *server)
+{
+ if (server->secmech.md5)
+ crypto_free_shash(server->secmech.md5);
+
+ if (server->secmech.hmacmd5)
+ crypto_free_shash(server->secmech.hmacmd5);
+
+ kfree(server->secmech.sdeschmacmd5);
+
+ kfree(server->secmech.sdescmd5);
+}
+
+int
+cifs_crypto_shash_allocate(struct TCP_Server_Info *server)
+{
+ int rc;
+ unsigned int size;
+
+ server->secmech.hmacmd5 = crypto_alloc_shash("hmac(md5)", 0, 0);
+ if (!server->secmech.hmacmd5 ||
+ IS_ERR(server->secmech.hmacmd5)) {
+ cERROR(1, "could not allocate crypto hmacmd5\n");
+ return PTR_ERR(server->secmech.hmacmd5);
+ }
+
+ server->secmech.md5 = crypto_alloc_shash("md5", 0, 0);
+ if (!server->secmech.md5 || IS_ERR(server->secmech.md5)) {
+ cERROR(1, "could not allocate crypto md5\n");
+ rc = PTR_ERR(server->secmech.md5);
+ goto crypto_allocate_md5_fail;
+ }
+
+ size = sizeof(struct shash_desc) +
+ crypto_shash_descsize(server->secmech.hmacmd5);
+ server->secmech.sdeschmacmd5 = kmalloc(size, GFP_KERNEL);
+ if (!server->secmech.sdeschmacmd5) {
+ cERROR(1, "cifs_crypto_shash_allocate: can't alloc hmacmd5\n");
+ rc = -ENOMEM;
+ goto crypto_allocate_hmacmd5_sdesc_fail;
+ }
+ server->secmech.sdeschmacmd5->shash.tfm = server->secmech.hmacmd5;
+ server->secmech.sdeschmacmd5->shash.flags = 0x0;
+
+
+ size = sizeof(struct shash_desc) +
+ crypto_shash_descsize(server->secmech.md5);
+ server->secmech.sdescmd5 = kmalloc(size, GFP_KERNEL);
+ if (!server->secmech.sdescmd5) {
+ cERROR(1, "cifs_crypto_shash_allocate: can't alloc md5\n");
+ rc = -ENOMEM;
+ goto crypto_allocate_md5_sdesc_fail;
+ }
+ server->secmech.sdescmd5->shash.tfm = server->secmech.md5;
+ server->secmech.sdescmd5->shash.flags = 0x0;
+
+ return 0;
+
+crypto_allocate_md5_sdesc_fail:
+ kfree(server->secmech.sdeschmacmd5);
+
+crypto_allocate_hmacmd5_sdesc_fail:
+ crypto_free_shash(server->secmech.md5);
+
+crypto_allocate_md5_fail:
+ crypto_free_shash(server->secmech.hmacmd5);
+
+ return rc;
+}
@@ -25,6 +25,9 @@
#include <linux/workqueue.h>
#include "cifs_fs_sb.h"
#include "cifsacl.h"
+#include <crypto/internal/hash.h>
+#include <linux/scatterlist.h>
+
/*
* The sizes of various internal tables and strings
*/
@@ -109,6 +112,28 @@ struct session_key {
} data;
};
+/* crypto security descriptor definition */
+struct sdesc {
+ struct shash_desc shash;
+ char ctx[];
+};
+
+/* crypto hashing related structure/fields, not speicific to a sec mech */
+struct cifs_secmech {
+ struct crypto_shash *hmacmd5; /* hmac-md5 hash function */
+ struct crypto_shash *md5; /* md5 hash function */
+ struct sdesc *sdeschmacmd5; /* ctxt to generate ntlmv2 hash, CR1 */
+ struct sdesc *sdescmd5; /* ctxt to generate cifs/smb signature */
+};
+
+/* per smb connection structure/fields */
+struct ntlmssp_auth {
+ __u32 client_flags; /* sent by client in type 1 ntlmsssp exchange */
+ __u32 server_flags; /* sent by server in type 2 ntlmssp exchange */
+ unsigned char sec_key[CIFS_CPHTXT_SIZE]; /* a nonce client generates */
+ unsigned char ciphertext[CIFS_CPHTXT_SIZE]; /* sent to server */
+};
+
struct cifs_cred {
int uid;
int gid;
@@ -187,6 +212,9 @@ struct TCP_Server_Info {
unsigned long lstrp; /* when we got last response from this server */
u16 dialect; /* dialect index that server chose */
/* extended security flavors that server supports */
+ struct cifs_secmech secmech; /* crypto sec mech functs, descriptors */
+ struct ntlmssp_auth ntlmssp; /* sec key, ciphertext, flags */
+ bool cphready; /* ciphertext is calculated */
bool sec_kerberos; /* supports plain Kerberos */
bool sec_mskerberos; /* supports legacy MS Kerberos */
bool sec_kerberosu2u; /* supports U2U Kerberos */
@@ -134,6 +134,13 @@
* Size of the session key (crypto key encrypted with the password
*/
#define CIFS_SESS_KEY_SIZE (24)
+#define CIFS_CLIENT_CHALLENGE_SIZE (8)
+#define CIFS_SERVER_CHALLENGE_SIZE (8)
+#define CIFS_HMAC_MD5_HASH_SIZE (16)
+#define CIFS_CPHTXT_SIZE (16)
+#define CIFS_NTLMV2_SESSKEY_SIZE (16)
+#define CIFS_NTHASH_SIZE (16)
+
/*
* Maximum user name length
@@ -369,6 +369,9 @@ extern int cifs_calculate_session_key(struct session_key *key, const char *rn,
extern void CalcNTLMv2_response(const struct cifsSesInfo *, char *);
extern int setup_ntlmv2_rsp(struct cifsSesInfo *, char *,
const struct nls_table *);
+extern int cifs_crypto_shash_allocate(struct TCP_Server_Info *);
+extern void cifs_crypto_shash_release(struct TCP_Server_Info *);
+extern int calc_seckey(struct TCP_Server_Info *);
#ifdef CONFIG_CIFS_WEAK_PW_HASH
extern void calc_lanman_hash(const char *password, const char *cryptkey,
bool encrypt, char *lnm_session_key);
@@ -199,6 +199,7 @@ cifs_reconnect(struct TCP_Server_Info *server)
if (server->tcpStatus != CifsExiting)
server->tcpStatus = CifsGood;
server->sequence_number = 0;
+ server->cphready = false;
spin_unlock(&GlobalMid_Lock);
/* atomic_set(&server->inFlight,0);*/
wake_up(&server->response_q);
@@ -1502,6 +1503,7 @@ cifs_put_tcp_session(struct TCP_Server_Info *server)
server->tcpStatus = CifsExiting;
spin_unlock(&GlobalMid_Lock);
+ cifs_crypto_shash_release(server);
cifs_fscache_release_client_cookie(server);
task = xchg(&server->tsk, NULL);
@@ -1556,12 +1558,19 @@ cifs_get_tcp_session(struct smb_vol *volume_info)
goto out_err;
}
+ rc = cifs_crypto_shash_allocate(tcp_ses);
+ if (rc) {
+ cERROR(1, "could not setup hash structures rc %d", rc);
+ goto out_err;
+ }
+
tcp_ses->hostname = extract_hostname(volume_info->UNC);
if (IS_ERR(tcp_ses->hostname)) {
rc = PTR_ERR(tcp_ses->hostname);
- goto out_err;
+ goto out_err2;
}
+ tcp_ses->cphready = false;
tcp_ses->noblocksnd = volume_info->noblocksnd;
tcp_ses->noautotune = volume_info->noautotune;
tcp_ses->tcp_nodelay = volume_info->sockopt_tcp_nodelay;
@@ -1600,7 +1609,7 @@ cifs_get_tcp_session(struct smb_vol *volume_info)
}
if (rc < 0) {
cERROR(1, "Error connecting to socket. Aborting operation");
- goto out_err;
+ goto out_err2;
}
/*
@@ -1614,7 +1623,7 @@ cifs_get_tcp_session(struct smb_vol *volume_info)
rc = PTR_ERR(tcp_ses->tsk);
cERROR(1, "error %d create cifsd thread", rc);
module_put(THIS_MODULE);
- goto out_err;
+ goto out_err2;
}
/* thread spawned, put it on the list */
@@ -1626,6 +1635,9 @@ cifs_get_tcp_session(struct smb_vol *volume_info)
return tcp_ses;
+out_err2:
+ cifs_crypto_shash_release(tcp_ses);
+
out_err:
if (tcp_ses) {
if (!IS_ERR(tcp_ses->hostname))
@@ -407,7 +407,7 @@ static int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
/* In particular we can examine sign flags */
/* BB spec says that if AvId field of MsvAvTimestamp is populated then
we must set the MIC field of the AUTHENTICATE_MESSAGE */
-
+ ses->server->ntlmssp.server_flags = le32_to_cpu(pblob->NegotiateFlags);
tioffset = cpu_to_le16(pblob->TargetInfoArray.BufferOffset);
tilen = cpu_to_le16(pblob->TargetInfoArray.Length);
ses->tilen = tilen;
@@ -443,10 +443,12 @@ static void build_ntlmssp_negotiate_blob(unsigned char *pbuffer,
NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
NTLMSSP_NEGOTIATE_NTLM;
if (ses->server->secMode &
- (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
+ (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) {
flags |= NTLMSSP_NEGOTIATE_SIGN;
- if (ses->server->secMode & SECMODE_SIGN_REQUIRED)
- flags |= NTLMSSP_NEGOTIATE_ALWAYS_SIGN;
+ if (!ses->server->cphready)
+ flags |= NTLMSSP_NEGOTIATE_KEY_XCH |
+ NTLMSSP_NEGOTIATE_EXTENDED_SEC;
+ }
sec_blob->NegotiateFlags |= cpu_to_le32(flags);
@@ -553,9 +555,19 @@ static int build_ntlmssp_auth_blob(unsigned char *pbuffer,
sec_blob->WorkstationName.MaximumLength = 0;
tmp += 2;
- sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - pbuffer);
- sec_blob->SessionKey.Length = 0;
- sec_blob->SessionKey.MaximumLength = 0;
+ if ((ses->server->ntlmssp.server_flags & NTLMSSP_NEGOTIATE_KEY_XCH) &&
+ !calc_seckey(ses->server)) {
+ memcpy(tmp, ses->server->ntlmssp.ciphertext, CIFS_CPHTXT_SIZE);
+ sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - pbuffer);
+ sec_blob->SessionKey.Length = cpu_to_le16(CIFS_CPHTXT_SIZE);
+ sec_blob->SessionKey.MaximumLength =
+ cpu_to_le16(CIFS_CPHTXT_SIZE);
+ tmp += CIFS_CPHTXT_SIZE;
+ } else {
+ sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - pbuffer);
+ sec_blob->SessionKey.Length = 0;
+ sec_blob->SessionKey.MaximumLength = 0;
+ }
setup_ntlmv2_ret:
return tmp - pbuffer;