aboutsummaryrefslogtreecommitdiffstats
path: root/fs/cifs/sess.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/cifs/sess.c')
-rw-r--r--fs/cifs/sess.c88
1 files changed, 3 insertions, 85 deletions
diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
index 5f99b7f19e78..e87387dbf39f 100644
--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -32,88 +32,6 @@
32#include <linux/slab.h> 32#include <linux/slab.h>
33#include "cifs_spnego.h" 33#include "cifs_spnego.h"
34 34
35/*
36 * Checks if this is the first smb session to be reconnected after
37 * the socket has been reestablished (so we know whether to use vc 0).
38 * Called while holding the cifs_tcp_ses_lock, so do not block
39 */
40static bool is_first_ses_reconnect(struct cifs_ses *ses)
41{
42 struct list_head *tmp;
43 struct cifs_ses *tmp_ses;
44
45 list_for_each(tmp, &ses->server->smb_ses_list) {
46 tmp_ses = list_entry(tmp, struct cifs_ses,
47 smb_ses_list);
48 if (tmp_ses->need_reconnect == false)
49 return false;
50 }
51 /* could not find a session that was already connected,
52 this must be the first one we are reconnecting */
53 return true;
54}
55
56/*
57 * vc number 0 is treated specially by some servers, and should be the
58 * first one we request. After that we can use vcnumbers up to maxvcs,
59 * one for each smb session (some Windows versions set maxvcs incorrectly
60 * so maxvc=1 can be ignored). If we have too many vcs, we can reuse
61 * any vc but zero (some servers reset the connection on vcnum zero)
62 *
63 */
64static __le16 get_next_vcnum(struct cifs_ses *ses)
65{
66 __u16 vcnum = 0;
67 struct list_head *tmp;
68 struct cifs_ses *tmp_ses;
69 __u16 max_vcs = ses->server->max_vcs;
70 __u16 i;
71 int free_vc_found = 0;
72
73 /* Quoting the MS-SMB specification: "Windows-based SMB servers set this
74 field to one but do not enforce this limit, which allows an SMB client
75 to establish more virtual circuits than allowed by this value ... but
76 other server implementations can enforce this limit." */
77 if (max_vcs < 2)
78 max_vcs = 0xFFFF;
79
80 spin_lock(&cifs_tcp_ses_lock);
81 if ((ses->need_reconnect) && is_first_ses_reconnect(ses))
82 goto get_vc_num_exit; /* vcnum will be zero */
83 for (i = ses->server->srv_count - 1; i < max_vcs; i++) {
84 if (i == 0) /* this is the only connection, use vc 0 */
85 break;
86
87 free_vc_found = 1;
88
89 list_for_each(tmp, &ses->server->smb_ses_list) {
90 tmp_ses = list_entry(tmp, struct cifs_ses,
91 smb_ses_list);
92 if (tmp_ses->vcnum == i) {
93 free_vc_found = 0;
94 break; /* found duplicate, try next vcnum */
95 }
96 }
97 if (free_vc_found)
98 break; /* we found a vcnumber that will work - use it */
99 }
100
101 if (i == 0)
102 vcnum = 0; /* for most common case, ie if one smb session, use
103 vc zero. Also for case when no free vcnum, zero
104 is safest to send (some clients only send zero) */
105 else if (free_vc_found == 0)
106 vcnum = 1; /* we can not reuse vc=0 safely, since some servers
107 reset all uids on that, but 1 is ok. */
108 else
109 vcnum = i;
110 ses->vcnum = vcnum;
111get_vc_num_exit:
112 spin_unlock(&cifs_tcp_ses_lock);
113
114 return cpu_to_le16(vcnum);
115}
116
117static __u32 cifs_ssetup_hdr(struct cifs_ses *ses, SESSION_SETUP_ANDX *pSMB) 35static __u32 cifs_ssetup_hdr(struct cifs_ses *ses, SESSION_SETUP_ANDX *pSMB)
118{ 36{
119 __u32 capabilities = 0; 37 __u32 capabilities = 0;
@@ -128,7 +46,7 @@ static __u32 cifs_ssetup_hdr(struct cifs_ses *ses, SESSION_SETUP_ANDX *pSMB)
128 CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4, 46 CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4,
129 USHRT_MAX)); 47 USHRT_MAX));
130 pSMB->req.MaxMpxCount = cpu_to_le16(ses->server->maxReq); 48 pSMB->req.MaxMpxCount = cpu_to_le16(ses->server->maxReq);
131 pSMB->req.VcNumber = get_next_vcnum(ses); 49 pSMB->req.VcNumber = __constant_cpu_to_le16(1);
132 50
133 /* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */ 51 /* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */
134 52
@@ -582,9 +500,9 @@ select_sectype(struct TCP_Server_Info *server, enum securityEnum requested)
582 return NTLMv2; 500 return NTLMv2;
583 if (global_secflags & CIFSSEC_MAY_NTLM) 501 if (global_secflags & CIFSSEC_MAY_NTLM)
584 return NTLM; 502 return NTLM;
585 /* Fallthrough */
586 default: 503 default:
587 return Unspecified; 504 /* Fallthrough to attempt LANMAN authentication next */
505 break;
588 } 506 }
589 case CIFS_NEGFLAVOR_LANMAN: 507 case CIFS_NEGFLAVOR_LANMAN:
590 switch (requested) { 508 switch (requested) {