diff options
| -rw-r--r-- | fs/cifs/Kconfig | 3 | ||||
| -rw-r--r-- | fs/cifs/cifsencrypt.c | 113 | ||||
| -rw-r--r-- | fs/cifs/cifsglob.h | 26 | ||||
| -rw-r--r-- | fs/cifs/cifspdu.h | 6 | ||||
| -rw-r--r-- | fs/cifs/cifsproto.h | 4 | ||||
| -rw-r--r-- | fs/cifs/connect.c | 16 | ||||
| -rw-r--r-- | fs/cifs/sess.c | 26 |
7 files changed, 184 insertions, 10 deletions
diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig index 917b7d4..0ed2139 100644 --- a/fs/cifs/Kconfig +++ b/fs/cifs/Kconfig @@ -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 diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c index 987b479..eaa2327 100644 --- a/fs/cifs/cifsencrypt.c +++ b/fs/cifs/cifsencrypt.c @@ -541,6 +541,119 @@ setup_ntlmv2_rsp_ret: return rc; } +int +calc_seckey(struct cifsSesInfo *ses) +{ + int rc; + struct crypto_blkcipher *tfm_arc4; + struct scatterlist sgin, sgout; + struct blkcipher_desc desc; + unsigned char sec_key[CIFS_SESS_KEY_SIZE]; /* a nonce */ + + get_random_bytes(sec_key, CIFS_SESS_KEY_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"); + return PTR_ERR(tfm_arc4); + } + + desc.tfm = tfm_arc4; + + crypto_blkcipher_setkey(tfm_arc4, ses->auth_key.response, + CIFS_SESS_KEY_SIZE); + + sg_init_one(&sgin, sec_key, CIFS_SESS_KEY_SIZE); + sg_init_one(&sgout, ses->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); + return rc; + } + + /* 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; + + crypto_free_blkcipher(tfm_arc4); + + 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; +} + void CalcNTLMv2_response(const struct cifsSesInfo *ses) { unsigned int offset = CIFS_SESS_KEY_SIZE + 8; diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index 66f76b2..7ca5f6d 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -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 */ @@ -102,6 +105,27 @@ struct session_key { char *response; }; +/* 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 ciphertext[CIFS_CPHTXT_SIZE]; /* sent to server */ +}; + struct cifs_cred { int uid; int gid; @@ -178,6 +202,7 @@ struct TCP_Server_Info { struct session_key session_key; unsigned long lstrp; /* when we got last response from this server */ u16 dialect; /* dialect index that server chose */ + struct cifs_secmech secmech; /* crypto sec mech functs, descriptors */ /* extended security flavors that server supports */ bool sec_kerberos; /* supports plain Kerberos */ bool sec_mskerberos; /* supports legacy MS Kerberos */ @@ -220,6 +245,7 @@ struct cifsSesInfo { char ntlmv2_hash[16]; unsigned int tilen; /* length of the target info blob */ unsigned char *tiblob; /* target info blob in challenge response */ + struct ntlmssp_auth ntlmssp; /* ciphertext, flags */ bool need_reconnect:1; /* connection reset, uid now invalid */ }; /* no more than one of the following three session flags may be set */ diff --git a/fs/cifs/cifspdu.h b/fs/cifs/cifspdu.h index a152cd6..de36b09 100644 --- a/fs/cifs/cifspdu.h +++ b/fs/cifs/cifspdu.h @@ -140,6 +140,12 @@ */ #define CIFS_SESS_KEY_SIZE (16) +#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_NTHASH_SIZE (16) + /* * Maximum user name length */ diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h index 8c2d0cf..1e4728b 100644 --- a/fs/cifs/cifsproto.h +++ b/fs/cifs/cifsproto.h @@ -368,6 +368,10 @@ extern void SMBNTencrypt(unsigned char *, unsigned char *, unsigned char *); extern int setup_ntlm_response(struct cifsSesInfo *); extern void CalcNTLMv2_response(const struct cifsSesInfo *); extern int setup_ntlmv2_rsp(struct cifsSesInfo *, 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 cifsSesInfo *); + #ifdef CONFIG_CIFS_WEAK_PW_HASH extern void calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt, char *lnm_session_key); diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index dd9a4ae..04239a7 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -1563,6 +1563,7 @@ 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); kfree(server->session_key.response); @@ -1621,10 +1622,16 @@ 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->noblocksnd = volume_info->noblocksnd; @@ -1668,7 +1675,7 @@ 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; } /* @@ -1682,7 +1689,7 @@ 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 */ @@ -1694,6 +1701,9 @@ 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)) diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c index b293468..d998c4f 100644 --- a/fs/cifs/sess.c +++ b/fs/cifs/sess.c @@ -404,7 +404,7 @@ 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->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; @@ -440,10 +440,12 @@ 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->session_estab) + flags |= NTLMSSP_NEGOTIATE_KEY_XCH | + NTLMSSP_NEGOTIATE_EXTENDED_SEC; + } sec_blob->NegotiateFlags |= cpu_to_le32(flags); @@ -543,9 +545,19 @@ 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->ntlmssp.server_flags & NTLMSSP_NEGOTIATE_KEY_XCH) && + !calc_seckey(ses)) { + memcpy(tmp, ses->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: *buflen = tmp - pbuffer; |
