cifs: Split Kerberos authentication off CIFS_SessSetup()

Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Reviewed-by: Shirish Pargaonkar <spargaonkar@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
This commit is contained in:
Sachin Prabhu 2014-06-16 15:35:27 +01:00 committed by Steve French
parent 583cf7afc7
commit ee03c646dd

View File

@ -963,6 +963,155 @@ out:
ses->auth_key.response = NULL;
}
#ifdef CONFIG_CIFS_UPCALL
static void
sess_auth_kerberos(struct sess_data *sess_data)
{
int rc = 0;
struct smb_hdr *smb_buf;
SESSION_SETUP_ANDX *pSMB;
char *bcc_ptr;
struct cifs_ses *ses = sess_data->ses;
__u32 capabilities;
__u16 bytes_remaining;
struct key *spnego_key = NULL;
struct cifs_spnego_msg *msg;
u16 blob_len;
/* extended security */
/* wct = 12 */
rc = sess_alloc_buffer(sess_data, 12);
if (rc)
goto out;
pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
bcc_ptr = sess_data->iov[2].iov_base;
capabilities = cifs_ssetup_hdr(ses, pSMB);
spnego_key = cifs_get_spnego_key(ses);
if (IS_ERR(spnego_key)) {
rc = PTR_ERR(spnego_key);
spnego_key = NULL;
goto out;
}
msg = spnego_key->payload.data;
/*
* check version field to make sure that cifs.upcall is
* sending us a response in an expected form
*/
if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
cifs_dbg(VFS,
"incorrect version of cifs.upcall (expected %d but got %d)",
CIFS_SPNEGO_UPCALL_VERSION, msg->version);
rc = -EKEYREJECTED;
goto out_put_spnego_key;
}
ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len,
GFP_KERNEL);
if (!ses->auth_key.response) {
cifs_dbg(VFS, "Kerberos can't allocate (%u bytes) memory",
msg->sesskey_len);
rc = -ENOMEM;
goto out_put_spnego_key;
}
ses->auth_key.len = msg->sesskey_len;
pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
capabilities |= CAP_EXTENDED_SECURITY;
pSMB->req.Capabilities = cpu_to_le32(capabilities);
sess_data->iov[1].iov_base = msg->data + msg->sesskey_len;
sess_data->iov[1].iov_len = msg->secblob_len;
pSMB->req.SecurityBlobLength = cpu_to_le16(sess_data->iov[1].iov_len);
if (ses->capabilities & CAP_UNICODE) {
/* unicode strings must be word aligned */
if ((sess_data->iov[0].iov_len
+ sess_data->iov[1].iov_len) % 2) {
*bcc_ptr = 0;
bcc_ptr++;
}
unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
unicode_domain_string(&bcc_ptr, ses, sess_data->nls_cp);
} else {
/* BB: is this right? */
ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
}
sess_data->iov[2].iov_len = (long) bcc_ptr -
(long) sess_data->iov[2].iov_base;
rc = sess_sendreceive(sess_data);
if (rc)
goto out_put_spnego_key;
pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
if (smb_buf->WordCount != 4) {
rc = -EIO;
cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
goto out_put_spnego_key;
}
if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
ses->Suid = smb_buf->Uid; /* UID left in wire format (le) */
cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
bytes_remaining = get_bcc(smb_buf);
bcc_ptr = pByteArea(smb_buf);
blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
if (blob_len > bytes_remaining) {
cifs_dbg(VFS, "bad security blob length %d\n",
blob_len);
rc = -EINVAL;
goto out_put_spnego_key;
}
bcc_ptr += blob_len;
bytes_remaining -= blob_len;
/* BB check if Unicode and decode strings */
if (bytes_remaining == 0) {
/* no string area to decode, do nothing */
} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
/* unicode string area must be word-aligned */
if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
++bcc_ptr;
--bytes_remaining;
}
decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
sess_data->nls_cp);
} else {
decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
sess_data->nls_cp);
}
rc = sess_establish_session(sess_data);
out_put_spnego_key:
key_invalidate(spnego_key);
key_put(spnego_key);
out:
sess_data->result = rc;
sess_data->func = NULL;
sess_free_buffer(sess_data);
kfree(ses->auth_key.response);
ses->auth_key.response = NULL;
}
#else
static void
sess_auth_kerberos(struct sess_data *sess_data)
{
cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
sess_data->result = -ENOSYS;
sess_data->func = NULL;
}
#endif /* ! CONFIG_CIFS_UPCALL */
int
CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
@ -980,7 +1129,6 @@ CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
struct kvec iov[3];
enum securityEnum type;
__u16 action, bytes_remaining;
struct key *spnego_key = NULL;
__le32 phase = NtLmNegotiate; /* NTLMSSP, if needed, is multistage */
u16 blob_len;
char *ntlmsspblob = NULL;
@ -1017,6 +1165,9 @@ CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
case NTLMv2:
sess_auth_ntlmv2(sess_data);
goto out;
case Kerberos:
sess_auth_kerberos(sess_data);
goto out;
default:
cifs_dbg(FYI, "Continuing with CIFS_SessSetup\n");
}
@ -1072,63 +1223,7 @@ ssetup_ntlmssp_authenticate:
iov[1].iov_base = NULL;
iov[1].iov_len = 0;
if (type == Kerberos) {
#ifdef CONFIG_CIFS_UPCALL
struct cifs_spnego_msg *msg;
spnego_key = cifs_get_spnego_key(ses);
if (IS_ERR(spnego_key)) {
rc = PTR_ERR(spnego_key);
spnego_key = NULL;
goto ssetup_exit;
}
msg = spnego_key->payload.data;
/* check version field to make sure that cifs.upcall is
sending us a response in an expected form */
if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
cifs_dbg(VFS, "incorrect version of cifs.upcall "
"expected %d but got %d)",
CIFS_SPNEGO_UPCALL_VERSION, msg->version);
rc = -EKEYREJECTED;
goto ssetup_exit;
}
ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len,
GFP_KERNEL);
if (!ses->auth_key.response) {
cifs_dbg(VFS,
"Kerberos can't allocate (%u bytes) memory",
msg->sesskey_len);
rc = -ENOMEM;
goto ssetup_exit;
}
ses->auth_key.len = msg->sesskey_len;
pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
capabilities |= CAP_EXTENDED_SECURITY;
pSMB->req.Capabilities = cpu_to_le32(capabilities);
iov[1].iov_base = msg->data + msg->sesskey_len;
iov[1].iov_len = msg->secblob_len;
pSMB->req.SecurityBlobLength = cpu_to_le16(iov[1].iov_len);
if (ses->capabilities & CAP_UNICODE) {
/* unicode strings must be word aligned */
if ((iov[0].iov_len + iov[1].iov_len) % 2) {
*bcc_ptr = 0;
bcc_ptr++;
}
unicode_oslm_strings(&bcc_ptr, nls_cp);
unicode_domain_string(&bcc_ptr, ses, nls_cp);
} else
/* BB: is this right? */
ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
#else /* ! CONFIG_CIFS_UPCALL */
cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
rc = -ENOSYS;
goto ssetup_exit;
#endif /* CONFIG_CIFS_UPCALL */
} else if (type == RawNTLMSSP) {
if (type == RawNTLMSSP) {
if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
rc = -ENOSYS;
@ -1268,10 +1363,6 @@ ssetup_ntlmssp_authenticate:
}
ssetup_exit:
if (spnego_key) {
key_invalidate(spnego_key);
key_put(spnego_key);
}
kfree(str_area);
kfree(ntlmsspblob);
ntlmsspblob = NULL;