svn commit: samba r13470 - in
branches/SAMBA_4_0/source/auth/ntlmssp: .
abartlet at samba.org
abartlet at samba.org
Sun Feb 12 12:42:37 GMT 2006
Author: abartlet
Date: 2006-02-12 12:42:37 +0000 (Sun, 12 Feb 2006)
New Revision: 13470
WebSVN: http://websvn.samba.org/cgi-bin/viewcvs.cgi?view=rev&root=samba&rev=13470
Log:
Thanks to a report from VL:
We were causing mayhem by weakening the keys at the wrong point in time.
I think this is the correct place to do it. The session key for SMB
signing, and the 'smb session key' (used for encrypting password sets)
is never weakened.
The session key used for bulk data encryption/signing is weakened.
This also makes more sense, when we look at the NTLM2 code.
Andrew Bartlett
Modified:
branches/SAMBA_4_0/source/auth/ntlmssp/ntlmssp.c
branches/SAMBA_4_0/source/auth/ntlmssp/ntlmssp_client.c
branches/SAMBA_4_0/source/auth/ntlmssp/ntlmssp_server.c
branches/SAMBA_4_0/source/auth/ntlmssp/ntlmssp_sign.c
Changeset:
Modified: branches/SAMBA_4_0/source/auth/ntlmssp/ntlmssp.c
===================================================================
--- branches/SAMBA_4_0/source/auth/ntlmssp/ntlmssp.c 2006-02-12 12:29:03 UTC (rev 13469)
+++ branches/SAMBA_4_0/source/auth/ntlmssp/ntlmssp.c 2006-02-12 12:42:37 UTC (rev 13470)
@@ -64,6 +64,8 @@
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_SIGN\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_SEAL)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_SEAL\n"));
+ if (neg_flags & NTLMSSP_NEGOTIATE_DATAGRAM_STYLE)
+ DEBUGADD(4, (" NTLMSSP_NEGOTIATE_DATAGRAM_STYLE\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_LM_KEY)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_LM_KEY\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_NETWARE)
@@ -78,6 +80,10 @@
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_THIS_IS_LOCAL_CALL\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_ALWAYS_SIGN)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_ALWAYS_SIGN\n"));
+ if (neg_flags & NTLMSSP_CHAL_ACCEPT_RESPONSE)
+ DEBUGADD(4, (" NTLMSSP_CHAL_ACCEPT_RESPONSE\n"));
+ if (neg_flags & NTLMSSP_CHAL_NON_NT_SESSION_KEY)
+ DEBUGADD(4, (" NTLMSSP_CHAL_NON_NT_SESSION_KEY\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_NTLM2)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_NTLM2\n"));
if (neg_flags & NTLMSSP_CHAL_TARGET_INFO)
@@ -86,6 +92,8 @@
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_128\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_KEY_EXCH\n"));
+ if (neg_flags & NTLMSSP_NEGOTIATE_56)
+ DEBUGADD(4, (" NTLMSSP_NEGOTIATE_56\n"));
}
static NTSTATUS gensec_ntlmssp_magic(struct gensec_security *gensec_security,
@@ -277,11 +285,16 @@
by the client lanman auth/lanman auth parameters, it isn't too bad.
*/
-void ntlmssp_weaken_keys(struct gensec_ntlmssp_state *gensec_ntlmssp_state)
+DATA_BLOB ntlmssp_weakend_key(struct gensec_ntlmssp_state *gensec_ntlmssp_state,
+ TALLOC_CTX *mem_ctx)
{
+ DATA_BLOB weakened_key = data_blob_talloc(mem_ctx,
+ gensec_ntlmssp_state->session_key.data,
+ gensec_ntlmssp_state->session_key.length);
/* Nothing to weaken. We certainly don't want to 'extend' the length... */
- if (gensec_ntlmssp_state->session_key.length < 8) {
- return;
+ if (weakened_key.length < 16) {
+ /* perhaps there was no key? */
+ return weakened_key;
}
/* Key weakening not performed on the master key for NTLM2
@@ -292,14 +305,15 @@
if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_128) {
} else if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_56) {
- gensec_ntlmssp_state->session_key.data[7] = 0xa0;
+ weakened_key.data[7] = 0xa0;
} else { /* forty bits */
- gensec_ntlmssp_state->session_key.data[5] = 0xe5;
- gensec_ntlmssp_state->session_key.data[6] = 0x38;
- gensec_ntlmssp_state->session_key.data[7] = 0xb0;
+ weakened_key.data[5] = 0xe5;
+ weakened_key.data[6] = 0x38;
+ weakened_key.data[7] = 0xb0;
}
- gensec_ntlmssp_state->session_key.length = 8;
+ weakened_key.length = 8;
}
+ return weakened_key;
}
static BOOL gensec_ntlmssp_have_feature(struct gensec_security *gensec_security,
Modified: branches/SAMBA_4_0/source/auth/ntlmssp/ntlmssp_client.c
===================================================================
--- branches/SAMBA_4_0/source/auth/ntlmssp/ntlmssp_client.c 2006-02-12 12:29:03 UTC (rev 13469)
+++ branches/SAMBA_4_0/source/auth/ntlmssp/ntlmssp_client.c 2006-02-12 12:42:37 UTC (rev 13470)
@@ -259,9 +259,6 @@
talloc_steal(out_mem_ctx, out->data);
- /* The client might be using 56 or 40 bit weakened keys */
- ntlmssp_weaken_keys(gensec_ntlmssp_state);
-
gensec_ntlmssp_state->chal = challenge_blob;
gensec_ntlmssp_state->lm_resp = lm_response;
talloc_steal(gensec_ntlmssp_state->lm_resp.data, lm_response.data);
Modified: branches/SAMBA_4_0/source/auth/ntlmssp/ntlmssp_server.c
===================================================================
--- branches/SAMBA_4_0/source/auth/ntlmssp/ntlmssp_server.c 2006-02-12 12:29:03 UTC (rev 13469)
+++ branches/SAMBA_4_0/source/auth/ntlmssp/ntlmssp_server.c 2006-02-12 12:42:37 UTC (rev 13470)
@@ -554,9 +554,6 @@
/* keep the session key around on the new context */
talloc_steal(gensec_ntlmssp_state, session_key.data);
- /* The server might need us to use a partial-strength session key */
- ntlmssp_weaken_keys(gensec_ntlmssp_state);
-
if ((gensec_security->want_features & GENSEC_FEATURE_SIGN)
|| (gensec_security->want_features & GENSEC_FEATURE_SEAL)) {
nt_status = ntlmssp_sign_init(gensec_ntlmssp_state);
Modified: branches/SAMBA_4_0/source/auth/ntlmssp/ntlmssp_sign.c
===================================================================
--- branches/SAMBA_4_0/source/auth/ntlmssp/ntlmssp_sign.c 2006-02-12 12:29:03 UTC (rev 13469)
+++ branches/SAMBA_4_0/source/auth/ntlmssp/ntlmssp_sign.c 2006-02-12 12:42:37 UTC (rev 13470)
@@ -299,13 +299,17 @@
*/
NTSTATUS ntlmssp_sign_init(struct gensec_ntlmssp_state *gensec_ntlmssp_state)
{
- uint8_t p24[24];
- ZERO_STRUCT(p24);
+ TALLOC_CTX *mem_ctx = talloc_new(gensec_ntlmssp_state);
+ if (!mem_ctx) {
+ return NT_STATUS_NO_MEMORY;
+ }
+
DEBUG(3, ("NTLMSSP Sign/Seal - Initialising with flags:\n"));
debug_ntlmssp_flags(gensec_ntlmssp_state->neg_flags);
- if (!gensec_ntlmssp_state->session_key.length) {
+ if (gensec_ntlmssp_state->session_key.length < 8) {
+ talloc_free(mem_ctx);
DEBUG(3, ("NO session key, cannot intialise signing\n"));
return NT_STATUS_NO_USER_SESSION_KEY;
}
@@ -335,6 +339,7 @@
recv_seal_const = CLI_SEAL;
break;
default:
+ talloc_free(mem_ctx);
return NT_STATUS_INTERNAL_ERROR;
}
@@ -368,7 +373,7 @@
weak_session_key.data,
weak_session_key.length);
- /* SEND */
+ /* SEND: sign key */
calc_ntlmv2_key(gensec_ntlmssp_state,
&gensec_ntlmssp_state->crypt.ntlm2.send_sign_key,
gensec_ntlmssp_state->session_key, send_sign_const);
@@ -376,21 +381,20 @@
gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.data,
gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.length);
- calc_ntlmv2_key(gensec_ntlmssp_state,
+ /* SEND: seal ARCFOUR pad */
+ calc_ntlmv2_key(mem_ctx,
&send_seal_key,
weak_session_key, send_seal_const);
dump_data_pw("NTLMSSP send seal key:\n",
send_seal_key.data,
send_seal_key.length);
-
arcfour_init(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state,
&send_seal_key);
-
dump_data_pw("NTLMSSP send sesl hash:\n",
gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state->sbox,
sizeof(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state->sbox));
- /* RECV */
+ /* RECV: sign key */
calc_ntlmv2_key(gensec_ntlmssp_state,
&gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key,
gensec_ntlmssp_state->session_key, recv_sign_const);
@@ -398,7 +402,8 @@
gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.length);
- calc_ntlmv2_key(gensec_ntlmssp_state,
+ /* RECV: seal ARCFOUR pad */
+ calc_ntlmv2_key(mem_ctx,
&recv_seal_key,
weak_session_key, recv_seal_const);
dump_data_pw("NTLMSSP recv seal key:\n",
@@ -406,7 +411,6 @@
recv_seal_key.length);
arcfour_init(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state,
&recv_seal_key);
-
dump_data_pw("NTLMSSP receive seal hash:\n",
gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state->sbox,
sizeof(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state->sbox));
@@ -415,19 +419,21 @@
gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num = 0;
} else {
+ DATA_BLOB weak_session_key = ntlmssp_weakend_key(gensec_ntlmssp_state, mem_ctx);
DEBUG(5, ("NTLMSSP Sign/Seal - using NTLM1\n"));
gensec_ntlmssp_state->crypt.ntlm.arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm.arcfour_state);
arcfour_init(gensec_ntlmssp_state->crypt.ntlm.arcfour_state,
- &gensec_ntlmssp_state->session_key);
+ &weak_session_key);
dump_data_pw("NTLMSSP hash:\n", gensec_ntlmssp_state->crypt.ntlm.arcfour_state->sbox,
sizeof(gensec_ntlmssp_state->crypt.ntlm.arcfour_state->sbox));
gensec_ntlmssp_state->crypt.ntlm.seq_num = 0;
}
+ talloc_free(mem_ctx);
return NT_STATUS_OK;
}
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