From: Shirish Pargaonkar <[email protected]> Use per smb session session key for signing for smb2 onwards. For each signature genereation/validation, look for corrosponding session (id) to fetch session key. Skip checking signature of the session setup response.
Signed-off-by: Shirish Pargaonkar <[email protected]> --- fs/cifs/cifsglob.h | 5 +++-- fs/cifs/cifsproto.h | 5 ++++- fs/cifs/connect.c | 14 +++++++++--- fs/cifs/smb2transport.c | 59 +++++++++++++++++++++++++++++++++++++++++-------- 4 files changed, 68 insertions(+), 15 deletions(-) diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index 2909380..4e24355 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -368,7 +368,8 @@ struct smb_version_operations { int (*perconnkey)(struct TCP_Server_Info *server, struct cifs_ses *ses); /* The next two functions will need to be changed to per smb session */ - void (*generate_signingkey)(struct TCP_Server_Info *server); + int (*generate_signingkey)(struct TCP_Server_Info *server, + struct cifs_ses *ses); int (*calc_signature)(struct smb_rqst *rqst, struct TCP_Server_Info *server); }; @@ -546,7 +547,6 @@ struct TCP_Server_Info { int timeAdj; /* Adjust for difference in server time zone in sec */ __u64 CurrentMid; /* multiplex id - rotating counter */ char cryptkey[CIFS_CRYPTO_KEY_SIZE]; /* used by ntlm, ntlmv2 etc */ - char smb3signingkey[SMB3_SIGN_KEY_SIZE]; /* for signing smb3 packets */ /* 16th byte of RFC1001 workstation name is always null */ char workstation_RFC1001_name[RFC1001_NAME_LEN_WITH_NULL]; __u32 sequence_number; /* for signing, protected by srv_mutex */ @@ -729,6 +729,7 @@ struct cifs_ses { bool need_reconnect:1; /* connection reset, uid now invalid */ #ifdef CONFIG_CIFS_SMB2 __u16 session_flags; + char smb3signingkey[SMB3_SIGN_KEY_SIZE]; /* for signing smb3 packets */ #endif /* CONFIG_CIFS_SMB2 */ }; diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h index b6c1d03..261c114 100644 --- a/fs/cifs/cifsproto.h +++ b/fs/cifs/cifsproto.h @@ -206,6 +206,8 @@ extern void cifs_dfs_release_automount_timer(void); void cifs_proc_init(void); void cifs_proc_clean(void); +extern void cifs_put_smb_ses(struct cifs_ses *); + extern void cifs_move_llist(struct list_head *source, struct list_head *dest); extern void cifs_free_llist(struct list_head *llist); extern void cifs_del_lock_waiters(struct cifsLockInfo *lock); @@ -435,7 +437,8 @@ extern int setup_ntlm_response(struct cifs_ses *, const struct nls_table *); extern int setup_ntlmv2_rsp(struct cifs_ses *, const struct nls_table *); extern void cifs_crypto_shash_release(struct TCP_Server_Info *); extern int calc_seckey(struct cifs_ses *); -extern void generate_smb3signingkey(struct TCP_Server_Info *); +extern int generate_smb3signingkey(struct TCP_Server_Info *, + struct cifs_ses *); extern int perconnkey(struct TCP_Server_Info *, struct cifs_ses *); extern void free_authkey(struct cifs_ses *); diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index 98deb98..0109046 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -2251,7 +2251,7 @@ cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb_vol *vol) return NULL; } -static void +void cifs_put_smb_ses(struct cifs_ses *ses) { unsigned int xid; @@ -3847,8 +3847,16 @@ cifs_setup_session(const unsigned int xid, struct cifs_ses *ses, server->sequence_number = 0x2; server->session_estab = true; } - if (server->ops->generate_signingkey) - server->ops->generate_signingkey(server); + if (server->ops->generate_signingkey) { + rc = server->ops->generate_signingkey(server, ses); + if (rc) { + cifs_dbg(VFS, + "%s: Failure to generate signing key\n", + __func__); + mutex_unlock(&server->srv_mutex); + goto setup_sess_ret; + } + } mutex_unlock(&server->srv_mutex); cifs_dbg(FYI, "CIFS Session Established successfully\n"); diff --git a/fs/cifs/smb2transport.c b/fs/cifs/smb2transport.c index 301b191..570e5b5 100644 --- a/fs/cifs/smb2transport.c +++ b/fs/cifs/smb2transport.c @@ -109,6 +109,24 @@ smb3_crypto_shash_allocate(struct TCP_Server_Info *server) return 0; } +static struct cifs_ses * +smb2_find_smb_ses(struct smb2_hdr *smb2hdr, struct TCP_Server_Info *server) +{ + struct cifs_ses *ses; + + spin_lock(&cifs_tcp_ses_lock); + list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) { + if (ses->Suid != smb2hdr->SessionId) + continue; + ++ses->ses_count; + spin_unlock(&cifs_tcp_ses_lock); + return ses; + } + spin_unlock(&cifs_tcp_ses_lock); + + return NULL; +} + int smb2_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server) @@ -119,23 +137,34 @@ smb2_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server) struct kvec *iov = rqst->rq_iov; int n_vec = rqst->rq_nvec; struct smb2_hdr *smb2_pdu = (struct smb2_hdr *)iov[0].iov_base; + struct cifs_ses *ses; + + ses = smb2_find_smb_ses(smb2_pdu, server); + if (!ses) { + cifs_dbg(VFS, "%s: Could not find session\n", __func__); + return 0; + } memset(smb2_signature, 0x0, SMB2_HMACSHA256_SIZE); memset(smb2_pdu->Signature, 0x0, SMB2_SIGNATURE_SIZE); rc = smb2_crypto_shash_allocate(server); if (rc) { + cifs_put_smb_ses(ses); cifs_dbg(VFS, "%s: shah256 alloc failed\n", __func__); return rc; } rc = crypto_shash_setkey(server->secmech.hmacsha256, - server->session_key.response, SMB2_NTLMV2_SESSKEY_SIZE); + ses->auth_key.response, SMB2_NTLMV2_SESSKEY_SIZE); if (rc) { + cifs_put_smb_ses(ses); cifs_dbg(VFS, "%s: Could not update with response\n", __func__); return rc; } + cifs_put_smb_ses(ses); + rc = crypto_shash_init(&server->secmech.sdeschmacsha256->shash); if (rc) { cifs_dbg(VFS, "%s: Could not init sha256", __func__); @@ -193,8 +222,8 @@ smb2_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server) return rc; } -void -generate_smb3signingkey(struct TCP_Server_Info *server) +int +generate_smb3signingkey(struct TCP_Server_Info *server, struct cifs_ses *ses) { unsigned char zero = 0x0; __u8 i[4] = {0, 0, 0, 1}; @@ -204,7 +233,7 @@ generate_smb3signingkey(struct TCP_Server_Info *server) unsigned char *hashptr = prfhash; memset(prfhash, 0x0, SMB2_HMACSHA256_SIZE); - memset(server->smb3signingkey, 0x0, SMB3_SIGNKEY_SIZE); + memset(ses->smb3signingkey, 0x0, SMB3_SIGNKEY_SIZE); rc = smb3_crypto_shash_allocate(server); if (rc) { @@ -213,7 +242,7 @@ generate_smb3signingkey(struct TCP_Server_Info *server) } rc = crypto_shash_setkey(server->secmech.hmacsha256, - server->session_key.response, SMB2_NTLMV2_SESSKEY_SIZE); + ses->auth_key.response, SMB2_NTLMV2_SESSKEY_SIZE); if (rc) { cifs_dbg(VFS, "%s: Could not set with session key\n", __func__); goto smb3signkey_ret; @@ -267,27 +296,38 @@ generate_smb3signingkey(struct TCP_Server_Info *server) goto smb3signkey_ret; } - memcpy(server->smb3signingkey, hashptr, SMB3_SIGNKEY_SIZE); + memcpy(ses->smb3signingkey, hashptr, SMB3_SIGNKEY_SIZE); smb3signkey_ret: - return; + return rc; } int smb3_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server) { - int i, rc; + int i; + int rc = 0; unsigned char smb3_signature[SMB2_CMACAES_SIZE]; unsigned char *sigptr = smb3_signature; struct kvec *iov = rqst->rq_iov; int n_vec = rqst->rq_nvec; struct smb2_hdr *smb2_pdu = (struct smb2_hdr *)iov[0].iov_base; + struct cifs_ses *ses; + + ses = smb2_find_smb_ses(smb2_pdu, server); + if (!ses) { + cifs_dbg(VFS, "%s: Could not find session\n", __func__); + return 0; + } memset(smb3_signature, 0x0, SMB2_CMACAES_SIZE); memset(smb2_pdu->Signature, 0x0, SMB2_SIGNATURE_SIZE); rc = crypto_shash_setkey(server->secmech.cmacaes, - server->smb3signingkey, SMB2_CMACAES_SIZE); + ses->smb3signingkey, SMB2_CMACAES_SIZE); + + cifs_put_smb_ses(ses); + if (rc) { cifs_dbg(VFS, "%s: Could not set key for cmac aes\n", __func__); return rc; @@ -384,6 +424,7 @@ smb2_verify_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server) struct smb2_hdr *smb2_pdu = (struct smb2_hdr *)rqst->rq_iov[0].iov_base; if ((smb2_pdu->Command == SMB2_NEGOTIATE) || + (smb2_pdu->Command == SMB2_SESSION_SETUP) || (smb2_pdu->Command == SMB2_OPLOCK_BREAK) || (!server->session_estab)) return 0; -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
