diff options
Diffstat (limited to 'fs/cifs/cifsencrypt.c')
| -rw-r--r-- | fs/cifs/cifsencrypt.c | 53 |
1 files changed, 51 insertions, 2 deletions
diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c index aa0dc2573374..afa09fce8151 100644 --- a/fs/cifs/cifsencrypt.c +++ b/fs/cifs/cifsencrypt.c @@ -444,6 +444,48 @@ find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp) return 0; } +/* Server has provided av pairs/target info in the type 2 challenge + * packet and we have plucked it and stored within smb session. + * We parse that blob here to find the server given timestamp + * as part of ntlmv2 authentication (or local current time as + * default in case of failure) + */ +static __le64 +find_timestamp(struct cifs_ses *ses) +{ + unsigned int attrsize; + unsigned int type; + unsigned int onesize = sizeof(struct ntlmssp2_name); + unsigned char *blobptr; + unsigned char *blobend; + struct ntlmssp2_name *attrptr; + + if (!ses->auth_key.len || !ses->auth_key.response) + return 0; + + blobptr = ses->auth_key.response; + blobend = blobptr + ses->auth_key.len; + + while (blobptr + onesize < blobend) { + attrptr = (struct ntlmssp2_name *) blobptr; + type = le16_to_cpu(attrptr->type); + if (type == NTLMSSP_AV_EOL) + break; + blobptr += 2; /* advance attr type */ + attrsize = le16_to_cpu(attrptr->length); + blobptr += 2; /* advance attr size */ + if (blobptr + attrsize > blobend) + break; + if (type == NTLMSSP_AV_TIMESTAMP) { + if (attrsize == sizeof(u64)) + return *((__le64 *)blobptr); + } + blobptr += attrsize; /* advance attr value */ + } + + return cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME)); +} + static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash, const struct nls_table *nls_cp) { @@ -641,6 +683,7 @@ setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp) struct ntlmv2_resp *ntlmv2; char ntlmv2_hash[16]; unsigned char *tiblob = NULL; /* target info blob */ + __le64 rsp_timestamp; if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED) { if (!ses->domainName) { @@ -659,6 +702,12 @@ setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp) } } + /* Must be within 5 minutes of the server (or in range +/-2h + * in case of Mac OS X), so simply carry over server timestamp + * (as Windows 7 does) + */ + rsp_timestamp = find_timestamp(ses); + baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp); tilen = ses->auth_key.len; tiblob = ses->auth_key.response; @@ -675,8 +724,8 @@ setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp) (ses->auth_key.response + CIFS_SESS_KEY_SIZE); ntlmv2->blob_signature = cpu_to_le32(0x00000101); ntlmv2->reserved = 0; - /* Must be within 5 minutes of the server */ - ntlmv2->time = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME)); + ntlmv2->time = rsp_timestamp; + get_random_bytes(&ntlmv2->client_chal, sizeof(ntlmv2->client_chal)); ntlmv2->reserved2 = 0; |