Improve interoperability of NTLM encryption/decryption and authentication - #71373

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wfurt merged 11 commits into
dotnet:mainfrom
filipnavara:smtpauth2
Jun 30, 2022
Merged

Improve interoperability of NTLM encryption/decryption and authentication#71373
wfurt merged 11 commits into
dotnet:mainfrom
filipnavara:smtpauth2

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@filipnavara

@filipnavarafilipnavara commented Jun 28, 2022•
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Best reviewed commit by commit.

Firstly, it fixes an interoperability scenario for non-encrypted NTLM communication passed through NegotiateStream between Unix and Windows. It updates the NegotiateStreamPal.Encrypt/Decrypt Unix implementation to have the same quirk as the Windows implementation has.

Secondly, it fixes a bunch of bugs in the SmtpClient GSSAPI authentication and adds a loopback server test. This was also tested against a real Microsoft Exchange server to ensure that it works properly and that the encryption/decryption is applied correctly in context of NTLM authentication.

@ghostghost added community-contribution Indicates that the PR has been added by a community member area-System.Net.Security labels Jun 28, 2022
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Issue Details

Built on top of #71280, best reviewed commit by commit.

Firstly, it fixes an interoperability scenario for non-encrypted NTLM communication passed through NegotiateStream between Unix and Windows. It updates the NegotiateStreamPal.Encrypt/Decrypt Unix implementation to have the same quirk as the Windows implementation has.

Secondly, it fixes a bunch of bugs in the SmtpClient GSSAPI authentication and adds a loopback server test. This was also tested against a real Microsoft Exchange server to ensure that it works properly and that the encryption/decryption is applied correctly in context of NTLM authentication.

Author:filipnavara
Assignees:-
Labels:

area-System.Net.Security, community-contribution

Milestone:-

@filipnavarafilipnavara mentioned this pull request Jun 29, 2022
Merged
@filipnavara
filipnavara marked this pull request as ready for review June 29, 2022 10:00
@filipnavara
filipnavara requested a review from wfurtJune 29, 2022 10:00
@filipnavara
Implement NTLM quirk in NegotiateStreamPal.Encrypt/Decrypt
a7dc399
NegotiateStream on non-encrypted connections with NTLM sends the
messages in a special `<signature token><plain text message>` format.
That's not something that gss_wrap/gss_unwrap would produce. It can be
produced through gss_get_mic/gss_verify_mic calls though so let's do
that.
@filipnavara
Remove MakeSignature/VerifySignature from SspiCli interop
9804db0
The method names were misleading since they wrapped the EncryptMessage
and DecryptMessage native APIs and not the MakeSignature/VerifySignature
APIs that also exist.
@filipnavara
Remove unused sequenceNumber parameters in NegotiateStreamPal.Encrypt…
c4c3200
…/Decrypt
The SSPI / GSSAPI providers keep track of the sequence numbers
themselves.
@filipnavara
Replace NTAuthentication.MakeSignature/VerifySignature with Wrap/Unwrap
6e634b9
This maps directly to the semantics of gss_wrap/gss_unwrap methods
that are used in many specifications. It replaces the misleading name
which in SSPI API is an equivalent of gss_get_mic/gss_verify_mic.
It also fixes the declaration to actually decode the buffers both
on Windows and Unix. In NTLM the content of the message is sealed
and needs to be decoded.
Note that previously on Unix the VerifySignature API didn't decode the
content. On Windows it did decode the content inside a buffer that was
passed as ReadOnlySpan<byte> but it didn't communicate back the offset
of the decoded data.
The SMTP GSSAPI authentication code was thus reading incorrect data.
In case the underlying authentication was Kerberos the data were
not encrypted and they were located at the beginning of the buffer
so it was not an issue. In case the underlying authentication was
NTLM it was looking at the NTLM signature token which luckily
happens to always start with the bytes 01 00 00 00. That exactly
matched the expected value by accident.
@filipnavara
Fix processing of last SMTP GSSAPI token
d801c84
The last token in the GSSAPI SASL authentication mechanism is a bit
mask that specifies the supported security protections offered by the
server and the maximum token size. The client is supposed to choose
one of the protections and reply back. Relax the check to actually
support servers that offer anything but "no protection". As long
as the server also offers no protection we can choose it.
@filipnavara
Update unit test to use the new Wrap/Unwrap APIs
c99f819
@filipnavara
Reset NTLM keys after successful Negotiate authentication
a8e835a
Updated the managed NTLM implementation and the fake servers to
implement the specification quirk:
MS-SPNG section 3.2.5.1 NTLM RC4 Key State for MechListMIC and First
Signed Message specifies that the RC4 sealing keys are reset back to
the initial state for the first message.
Since the managed implementation doesn't expose encryption yet it
didn't affect any observable behavior. Likewise the fake servers
didn't need this code path yet.
@filipnavara
Add GSSAPI authentication test to the loopback SMTP server
a57be6a
@filipnavara
Workaround forgssapi/gss-ntlmssp#77
67b12d9
@filipnavara
Expose the confidentiality flag from the native gss_wrap/unwrap APIs
5926042
wfurt
wfurt approved these changes Jun 29, 2022
View reviewed changes

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LGTM.
cc: @SteveSyfuhs for any thoughts on the GSSAPI/SSPI changes.

@wfurt

wfurt commented Jun 29, 2022

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contributes to #19436

@wfurtwfurt mentioned this pull request Jun 30, 2022
Merged
@wfurt
wfurt merged commit ac9e1f9 into dotnet:mainJun 30, 2022
@karelzkarelz added this to the 7.0.0 milestone Jul 19, 2022
@ghostghost locked as resolved and limited conversation to collaborators Aug 18, 2022
@filipnavara
filipnavara deleted the smtpauth2 branch June 5, 2025 07:39
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@filipnavara@wfurt@karelz
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Improve interoperability of NTLM encryption/decryption and authentication - #71373
Merged
wfurt merged 11 commits into
dotnet:mainfrom 
filipnavara:smtpauth2
Jun 30, 2022
Merged
Improve interoperability of NTLM encryption/decryption and authentication#71373
wfurt merged 11 commits into
dotnet:mainfrom 
filipnavara:smtpauth2
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@filipnavara
@filipnavarafilipnavara
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Jun 28, 2022•

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Best reviewed commit by commit.
Firstly, it fixes an interoperability scenario for non-encrypted NTLM communication passed through NegotiateStream between Unix and Windows. It updates the NegotiateStreamPal.Encrypt/Decrypt Unix implementation to have the same quirk as the Windows implementation has.
Secondly, it fixes a bunch of bugs in the SmtpClient GSSAPI authentication and adds a loopback server test. This was also tested against a real Microsoft Exchange server to ensure that it works properly and that the encryption/decryption is applied correctly in context of NTLM authentication.
@ghostghost
added

community-contribution
Indicates that the PR has been added by a community member
area-System.Net.Security

labels
Jun 28, 2022
@ghost
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Tagging subscribers to this area: @dotnet/ncl, @vcsjones

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Issue Details
Built on top of #71280, best reviewed commit by commit.
Firstly, it fixes an interoperability scenario for non-encrypted NTLM communication passed through NegotiateStream between Unix and Windows. It updates the NegotiateStreamPal.Encrypt/Decrypt Unix implementation to have the same quirk as the Windows implementation has.
Secondly, it fixes a bunch of bugs in the SmtpClient GSSAPI authentication and adds a loopback server test. This was also tested against a real Microsoft Exchange server to ensure that it works properly and that the encryption/decryption is applied correctly in context of NTLM authentication.
Author:filipnavara
Assignees:-
Labels:
area-System.Net.Security, community-contribution
Milestone:-
@filipnavarafilipnavara
mentioned this pull request
Jun 29, 2022
 Merged

@filipnavara
filipnavara
marked this pull request as ready for review
June 29, 2022 10:00
@filipnavara
filipnavara
requested a review
from wfurtJune 29, 2022 10:00
@filipnavara
Implement NTLM quirk in NegotiateStreamPal.Encrypt/Decrypt
a7dc399
NegotiateStream on non-encrypted connections with NTLM sends the
messages in a special `<signature token><plain text message>` format.
That's not something that gss_wrap/gss_unwrap would produce. It can be
produced through gss_get_mic/gss_verify_mic calls though so let's do
that.
@filipnavara
Remove MakeSignature/VerifySignature from SspiCli interop
9804db0
The method names were misleading since they wrapped the EncryptMessage
and DecryptMessage native APIs and not the MakeSignature/VerifySignature
APIs that also exist.
@filipnavara
Remove unused sequenceNumber parameters in NegotiateStreamPal.Encrypt…
c4c3200
…/Decrypt
The SSPI / GSSAPI providers keep track of the sequence numbers
themselves.
@filipnavara
Replace NTAuthentication.MakeSignature/VerifySignature with Wrap/Unwrap
6e634b9
This maps directly to the semantics of gss_wrap/gss_unwrap methods
that are used in many specifications. It replaces the misleading name
which in SSPI API is an equivalent of gss_get_mic/gss_verify_mic.
It also fixes the declaration to actually decode the buffers both
on Windows and Unix. In NTLM the content of the message is sealed
and needs to be decoded.
Note that previously on Unix the VerifySignature API didn't decode the
content. On Windows it did decode the content inside a buffer that was
passed as ReadOnlySpan<byte> but it didn't communicate back the offset
of the decoded data.
The SMTP GSSAPI authentication code was thus reading incorrect data.
In case the underlying authentication was Kerberos the data were
not encrypted and they were located at the beginning of the buffer
so it was not an issue. In case the underlying authentication was
NTLM it was looking at the NTLM signature token which luckily
happens to always start with the bytes 01 00 00 00. That exactly
matched the expected value by accident.
@filipnavara
Fix processing of last SMTP GSSAPI token
d801c84
The last token in the GSSAPI SASL authentication mechanism is a bit
mask that specifies the supported security protections offered by the
server and the maximum token size. The client is supposed to choose
one of the protections and reply back. Relax the check to actually
support servers that offer anything but "no protection". As long
as the server also offers no protection we can choose it.
@filipnavara
Update unit test to use the new Wrap/Unwrap APIs
c99f819
@filipnavara
Reset NTLM keys after successful Negotiate authentication
a8e835a
Updated the managed NTLM implementation and the fake servers to
implement the specification quirk:
MS-SPNG section 3.2.5.1 NTLM RC4 Key State for MechListMIC and First
Signed Message specifies that the RC4 sealing keys are reset back to
the initial state for the first message.
Since the managed implementation doesn't expose encryption yet it
didn't affect any observable behavior. Likewise the fake servers
didn't need this code path yet.
@filipnavara
Add GSSAPI authentication test to the loopback SMTP server
a57be6a
@filipnavara
Workaround forgssapi/gss-ntlmssp#77
67b12d9
@filipnavara
Expose the confidentiality flag from the native gss_wrap/unwrap APIs
5926042
wfurt
wfurt
approved these changes
Jun 29, 2022
View reviewed changes
@wfurtwfurt
left a comment


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LGTM.

cc: @SteveSyfuhs for any thoughts on the GSSAPI/SSPI changes.
@wfurt
wfurt
commented
Jun 29, 2022

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contributes to #19436
@wfurtwfurt
mentioned this pull request
Jun 30, 2022
 Merged

@wfurt
wfurt
merged commit ac9e1f9
into
dotnet:mainJun 30, 2022
@karelzkarelz
added this to the 7.0.0 milestone
Jul 19, 2022
@ghostghost
locked as resolved and limited conversation to collaborators
Aug 18, 2022
@filipnavara
filipnavara
deleted the

smtpauth2

branch
June 5, 2025 07:39
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Skip to content
Improve interoperability of NTLM encryption/decryption and authentication - #71373
Merged
wfurt merged 11 commits into
dotnet:mainfrom 
filipnavara:smtpauth2
Jun 30, 2022
Merged
Improve interoperability of NTLM encryption/decryption and authentication#71373
wfurt merged 11 commits into
dotnet:mainfrom 
filipnavara:smtpauth2
Conversation
@filipnavara
@filipnavarafilipnavara
commented
Jun 28, 2022•

edited

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Best reviewed commit by commit.
Firstly, it fixes an interoperability scenario for non-encrypted NTLM communication passed through NegotiateStream between Unix and Windows. It updates the NegotiateStreamPal.Encrypt/Decrypt Unix implementation to have the same quirk as the Windows implementation has.
Secondly, it fixes a bunch of bugs in the SmtpClient GSSAPI authentication and adds a loopback server test. This was also tested against a real Microsoft Exchange server to ensure that it works properly and that the encryption/decryption is applied correctly in context of NTLM authentication.
@ghostghost
added

community-contribution
Indicates that the PR has been added by a community member
area-System.Net.Security

labels
Jun 28, 2022
@ghost
ghost
commented
Jun 28, 2022

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Tagging subscribers to this area: @dotnet/ncl, @vcsjones

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Issue Details
Built on top of #71280, best reviewed commit by commit.
Firstly, it fixes an interoperability scenario for non-encrypted NTLM communication passed through NegotiateStream between Unix and Windows. It updates the NegotiateStreamPal.Encrypt/Decrypt Unix implementation to have the same quirk as the Windows implementation has.
Secondly, it fixes a bunch of bugs in the SmtpClient GSSAPI authentication and adds a loopback server test. This was also tested against a real Microsoft Exchange server to ensure that it works properly and that the encryption/decryption is applied correctly in context of NTLM authentication.
Author:filipnavara
Assignees:-
Labels:
area-System.Net.Security, community-contribution
Milestone:-
@filipnavarafilipnavara
mentioned this pull request
Jun 29, 2022
 Merged

@filipnavara
filipnavara
marked this pull request as ready for review
June 29, 2022 10:00
@filipnavara
filipnavara
requested a review
from wfurtJune 29, 2022 10:00
@filipnavara
Implement NTLM quirk in NegotiateStreamPal.Encrypt/Decrypt
a7dc399
NegotiateStream on non-encrypted connections with NTLM sends the
messages in a special `<signature token><plain text message>` format.
That's not something that gss_wrap/gss_unwrap would produce. It can be
produced through gss_get_mic/gss_verify_mic calls though so let's do
that.
@filipnavara
Remove MakeSignature/VerifySignature from SspiCli interop
9804db0
The method names were misleading since they wrapped the EncryptMessage
and DecryptMessage native APIs and not the MakeSignature/VerifySignature
APIs that also exist.
@filipnavara
Remove unused sequenceNumber parameters in NegotiateStreamPal.Encrypt…
c4c3200
…/Decrypt
The SSPI / GSSAPI providers keep track of the sequence numbers
themselves.
@filipnavara
Replace NTAuthentication.MakeSignature/VerifySignature with Wrap/Unwrap
6e634b9
This maps directly to the semantics of gss_wrap/gss_unwrap methods
that are used in many specifications. It replaces the misleading name
which in SSPI API is an equivalent of gss_get_mic/gss_verify_mic.
It also fixes the declaration to actually decode the buffers both
on Windows and Unix. In NTLM the content of the message is sealed
and needs to be decoded.
Note that previously on Unix the VerifySignature API didn't decode the
content. On Windows it did decode the content inside a buffer that was
passed as ReadOnlySpan<byte> but it didn't communicate back the offset
of the decoded data.
The SMTP GSSAPI authentication code was thus reading incorrect data.
In case the underlying authentication was Kerberos the data were
not encrypted and they were located at the beginning of the buffer
so it was not an issue. In case the underlying authentication was
NTLM it was looking at the NTLM signature token which luckily
happens to always start with the bytes 01 00 00 00. That exactly
matched the expected value by accident.
@filipnavara
Fix processing of last SMTP GSSAPI token
d801c84
The last token in the GSSAPI SASL authentication mechanism is a bit
mask that specifies the supported security protections offered by the
server and the maximum token size. The client is supposed to choose
one of the protections and reply back. Relax the check to actually
support servers that offer anything but "no protection". As long
as the server also offers no protection we can choose it.
@filipnavara
Update unit test to use the new Wrap/Unwrap APIs
c99f819
@filipnavara
Reset NTLM keys after successful Negotiate authentication
a8e835a
Updated the managed NTLM implementation and the fake servers to
implement the specification quirk:
MS-SPNG section 3.2.5.1 NTLM RC4 Key State for MechListMIC and First
Signed Message specifies that the RC4 sealing keys are reset back to
the initial state for the first message.
Since the managed implementation doesn't expose encryption yet it
didn't affect any observable behavior. Likewise the fake servers
didn't need this code path yet.
@filipnavara
Add GSSAPI authentication test to the loopback SMTP server
a57be6a
@filipnavara
Workaround forgssapi/gss-ntlmssp#77
67b12d9
@filipnavara
Expose the confidentiality flag from the native gss_wrap/unwrap APIs
5926042
wfurt
wfurt
approved these changes
Jun 29, 2022
View reviewed changes
@wfurtwfurt
left a comment


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LGTM.

cc: @SteveSyfuhs for any thoughts on the GSSAPI/SSPI changes.
@wfurt
wfurt
commented
Jun 29, 2022

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contributes to #19436
@wfurtwfurt
mentioned this pull request
Jun 30, 2022
 Merged

@wfurt
wfurt
merged commit ac9e1f9
into
dotnet:mainJun 30, 2022
@karelzkarelz
added this to the 7.0.0 milestone
Jul 19, 2022
@ghostghost
locked as resolved and limited conversation to collaborators
Aug 18, 2022
@filipnavara
filipnavara
deleted the

smtpauth2

branch
June 5, 2025 07:39
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Skip to content
Improve interoperability of NTLM encryption/decryption and authentication - #71373
Merged
wfurt merged 11 commits into
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filipnavara:smtpauth2
Jun 30, 2022
Merged
Improve interoperability of NTLM encryption/decryption and authentication#71373
wfurt merged 11 commits into
dotnet:mainfrom 
filipnavara:smtpauth2
Conversation
@filipnavara
@filipnavarafilipnavara
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Jun 28, 2022•

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Best reviewed commit by commit.
Firstly, it fixes an interoperability scenario for non-encrypted NTLM communication passed through NegotiateStream between Unix and Windows. It updates the NegotiateStreamPal.Encrypt/Decrypt Unix implementation to have the same quirk as the Windows implementation has.
Secondly, it fixes a bunch of bugs in the SmtpClient GSSAPI authentication and adds a loopback server test. This was also tested against a real Microsoft Exchange server to ensure that it works properly and that the encryption/decryption is applied correctly in context of NTLM authentication.
@ghostghost
added

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Indicates that the PR has been added by a community member
area-System.Net.Security

labels
Jun 28, 2022
@ghost
ghost
commented
Jun 28, 2022

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Tagging subscribers to this area: @dotnet/ncl, @vcsjones

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Issue Details
Built on top of #71280, best reviewed commit by commit.
Firstly, it fixes an interoperability scenario for non-encrypted NTLM communication passed through NegotiateStream between Unix and Windows. It updates the NegotiateStreamPal.Encrypt/Decrypt Unix implementation to have the same quirk as the Windows implementation has.
Secondly, it fixes a bunch of bugs in the SmtpClient GSSAPI authentication and adds a loopback server test. This was also tested against a real Microsoft Exchange server to ensure that it works properly and that the encryption/decryption is applied correctly in context of NTLM authentication.
Author:filipnavara
Assignees:-
Labels:
area-System.Net.Security, community-contribution
Milestone:-
@filipnavarafilipnavara
mentioned this pull request
Jun 29, 2022
 Merged

@filipnavara
filipnavara
marked this pull request as ready for review
June 29, 2022 10:00
@filipnavara
filipnavara
requested a review
from wfurtJune 29, 2022 10:00
@filipnavara
Implement NTLM quirk in NegotiateStreamPal.Encrypt/Decrypt
a7dc399
NegotiateStream on non-encrypted connections with NTLM sends the
messages in a special `<signature token><plain text message>` format.
That's not something that gss_wrap/gss_unwrap would produce. It can be
produced through gss_get_mic/gss_verify_mic calls though so let's do
that.
@filipnavara
Remove MakeSignature/VerifySignature from SspiCli interop
9804db0
The method names were misleading since they wrapped the EncryptMessage
and DecryptMessage native APIs and not the MakeSignature/VerifySignature
APIs that also exist.
@filipnavara
Remove unused sequenceNumber parameters in NegotiateStreamPal.Encrypt…
c4c3200
…/Decrypt
The SSPI / GSSAPI providers keep track of the sequence numbers
themselves.
@filipnavara
Replace NTAuthentication.MakeSignature/VerifySignature with Wrap/Unwrap
6e634b9
This maps directly to the semantics of gss_wrap/gss_unwrap methods
that are used in many specifications. It replaces the misleading name
which in SSPI API is an equivalent of gss_get_mic/gss_verify_mic.
It also fixes the declaration to actually decode the buffers both
on Windows and Unix. In NTLM the content of the message is sealed
and needs to be decoded.
Note that previously on Unix the VerifySignature API didn't decode the
content. On Windows it did decode the content inside a buffer that was
passed as ReadOnlySpan<byte> but it didn't communicate back the offset
of the decoded data.
The SMTP GSSAPI authentication code was thus reading incorrect data.
In case the underlying authentication was Kerberos the data were
not encrypted and they were located at the beginning of the buffer
so it was not an issue. In case the underlying authentication was
NTLM it was looking at the NTLM signature token which luckily
happens to always start with the bytes 01 00 00 00. That exactly
matched the expected value by accident.
@filipnavara
Fix processing of last SMTP GSSAPI token
d801c84
The last token in the GSSAPI SASL authentication mechanism is a bit
mask that specifies the supported security protections offered by the
server and the maximum token size. The client is supposed to choose
one of the protections and reply back. Relax the check to actually
support servers that offer anything but "no protection". As long
as the server also offers no protection we can choose it.
@filipnavara
Update unit test to use the new Wrap/Unwrap APIs
c99f819
@filipnavara
Reset NTLM keys after successful Negotiate authentication
a8e835a
Updated the managed NTLM implementation and the fake servers to
implement the specification quirk:
MS-SPNG section 3.2.5.1 NTLM RC4 Key State for MechListMIC and First
Signed Message specifies that the RC4 sealing keys are reset back to
the initial state for the first message.
Since the managed implementation doesn't expose encryption yet it
didn't affect any observable behavior. Likewise the fake servers
didn't need this code path yet.
@filipnavara
Add GSSAPI authentication test to the loopback SMTP server
a57be6a
@filipnavara
Workaround forgssapi/gss-ntlmssp#77
67b12d9
@filipnavara
Expose the confidentiality flag from the native gss_wrap/unwrap APIs
5926042
wfurt
wfurt
approved these changes
Jun 29, 2022
View reviewed changes
@wfurtwfurt
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LGTM.

cc: @SteveSyfuhs for any thoughts on the GSSAPI/SSPI changes.
@wfurt
wfurt
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Jun 29, 2022

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contributes to #19436
@wfurtwfurt
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Jun 30, 2022
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@wfurt
wfurt
merged commit ac9e1f9
into
dotnet:mainJun 30, 2022
@karelzkarelz
added this to the 7.0.0 milestone
Jul 19, 2022
@ghostghost
locked as resolved and limited conversation to collaborators
Aug 18, 2022
@filipnavara
filipnavara
deleted the

smtpauth2

branch
June 5, 2025 07:39
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try {
var __m = "youtube.com";
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Skip to content
Improve interoperability of NTLM encryption/decryption and authentication - #71373
Merged
wfurt merged 11 commits into
dotnet:mainfrom 
filipnavara:smtpauth2
Jun 30, 2022
Merged
Improve interoperability of NTLM encryption/decryption and authentication#71373
wfurt merged 11 commits into
dotnet:mainfrom 
filipnavara:smtpauth2
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@filipnavara
@filipnavarafilipnavara
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Jun 28, 2022•

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Best reviewed commit by commit.
Firstly, it fixes an interoperability scenario for non-encrypted NTLM communication passed through NegotiateStream between Unix and Windows. It updates the NegotiateStreamPal.Encrypt/Decrypt Unix implementation to have the same quirk as the Windows implementation has.
Secondly, it fixes a bunch of bugs in the SmtpClient GSSAPI authentication and adds a loopback server test. This was also tested against a real Microsoft Exchange server to ensure that it works properly and that the encryption/decryption is applied correctly in context of NTLM authentication.
@ghostghost
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Jun 28, 2022
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Jun 28, 2022

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Tagging subscribers to this area: @dotnet/ncl, @vcsjones

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Issue Details
Built on top of #71280, best reviewed commit by commit.
Firstly, it fixes an interoperability scenario for non-encrypted NTLM communication passed through NegotiateStream between Unix and Windows. It updates the NegotiateStreamPal.Encrypt/Decrypt Unix implementation to have the same quirk as the Windows implementation has.
Secondly, it fixes a bunch of bugs in the SmtpClient GSSAPI authentication and adds a loopback server test. This was also tested against a real Microsoft Exchange server to ensure that it works properly and that the encryption/decryption is applied correctly in context of NTLM authentication.
Author:filipnavara
Assignees:-
Labels:
area-System.Net.Security, community-contribution
Milestone:-
@filipnavarafilipnavara
mentioned this pull request
Jun 29, 2022
 Merged

@filipnavara
filipnavara
marked this pull request as ready for review
June 29, 2022 10:00
@filipnavara
filipnavara
requested a review
from wfurtJune 29, 2022 10:00
@filipnavara
Implement NTLM quirk in NegotiateStreamPal.Encrypt/Decrypt
a7dc399
NegotiateStream on non-encrypted connections with NTLM sends the
messages in a special `<signature token><plain text message>` format.
That's not something that gss_wrap/gss_unwrap would produce. It can be
produced through gss_get_mic/gss_verify_mic calls though so let's do
that.
@filipnavara
Remove MakeSignature/VerifySignature from SspiCli interop
9804db0
The method names were misleading since they wrapped the EncryptMessage
and DecryptMessage native APIs and not the MakeSignature/VerifySignature
APIs that also exist.
@filipnavara
Remove unused sequenceNumber parameters in NegotiateStreamPal.Encrypt…
c4c3200
…/Decrypt
The SSPI / GSSAPI providers keep track of the sequence numbers
themselves.
@filipnavara
Replace NTAuthentication.MakeSignature/VerifySignature with Wrap/Unwrap
6e634b9
This maps directly to the semantics of gss_wrap/gss_unwrap methods
that are used in many specifications. It replaces the misleading name
which in SSPI API is an equivalent of gss_get_mic/gss_verify_mic.
It also fixes the declaration to actually decode the buffers both
on Windows and Unix. In NTLM the content of the message is sealed
and needs to be decoded.
Note that previously on Unix the VerifySignature API didn't decode the
content. On Windows it did decode the content inside a buffer that was
passed as ReadOnlySpan<byte> but it didn't communicate back the offset
of the decoded data.
The SMTP GSSAPI authentication code was thus reading incorrect data.
In case the underlying authentication was Kerberos the data were
not encrypted and they were located at the beginning of the buffer
so it was not an issue. In case the underlying authentication was
NTLM it was looking at the NTLM signature token which luckily
happens to always start with the bytes 01 00 00 00. That exactly
matched the expected value by accident.
@filipnavara
Fix processing of last SMTP GSSAPI token
d801c84
The last token in the GSSAPI SASL authentication mechanism is a bit
mask that specifies the supported security protections offered by the
server and the maximum token size. The client is supposed to choose
one of the protections and reply back. Relax the check to actually
support servers that offer anything but "no protection". As long
as the server also offers no protection we can choose it.
@filipnavara
Update unit test to use the new Wrap/Unwrap APIs
c99f819
@filipnavara
Reset NTLM keys after successful Negotiate authentication
a8e835a
Updated the managed NTLM implementation and the fake servers to
implement the specification quirk:
MS-SPNG section 3.2.5.1 NTLM RC4 Key State for MechListMIC and First
Signed Message specifies that the RC4 sealing keys are reset back to
the initial state for the first message.
Since the managed implementation doesn't expose encryption yet it
didn't affect any observable behavior. Likewise the fake servers
didn't need this code path yet.
@filipnavara
Add GSSAPI authentication test to the loopback SMTP server
a57be6a
@filipnavara
Workaround forgssapi/gss-ntlmssp#77
67b12d9
@filipnavara
Expose the confidentiality flag from the native gss_wrap/unwrap APIs
5926042
wfurt
wfurt
approved these changes
Jun 29, 2022
View reviewed changes
@wfurtwfurt
left a comment


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LGTM.

cc: @SteveSyfuhs for any thoughts on the GSSAPI/SSPI changes.
@wfurt
wfurt
commented
Jun 29, 2022

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contributes to #19436
@wfurtwfurt
mentioned this pull request
Jun 30, 2022
 Merged

@wfurt
wfurt
merged commit ac9e1f9
into
dotnet:mainJun 30, 2022
@karelzkarelz
added this to the 7.0.0 milestone
Jul 19, 2022
@ghostghost
locked as resolved and limited conversation to collaborators
Aug 18, 2022
@filipnavara
filipnavara
deleted the

smtpauth2

branch
June 5, 2025 07:39
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@filipnavara@wfurt@karelz

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Auto-enable theater mode on YouTube
(function() {
function tryTheater() {
var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]');
if (btn && !btn.classList.contains('activated')) {
btn.click();
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// Try immediately
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// Try after navigation (SPA)
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setInterval(function() {
if (location.href !== lastUrl) {
lastUrl = location.href;
setTimeout(tryTheater, 500);
}
}, 1000);
// Also try on player load
var observer = new MutationObserver(tryTheater);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
Improve interoperability of NTLM encryption/decryption and authentication - #71373
Merged
wfurt merged 11 commits into
dotnet:mainfrom 
filipnavara:smtpauth2
Jun 30, 2022
Merged
Improve interoperability of NTLM encryption/decryption and authentication#71373
wfurt merged 11 commits into
dotnet:mainfrom 
filipnavara:smtpauth2
Conversation
@filipnavara
@filipnavarafilipnavara
commented
Jun 28, 2022•

edited

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Member
Best reviewed commit by commit.
Firstly, it fixes an interoperability scenario for non-encrypted NTLM communication passed through NegotiateStream between Unix and Windows. It updates the NegotiateStreamPal.Encrypt/Decrypt Unix implementation to have the same quirk as the Windows implementation has.
Secondly, it fixes a bunch of bugs in the SmtpClient GSSAPI authentication and adds a loopback server test. This was also tested against a real Microsoft Exchange server to ensure that it works properly and that the encryption/decryption is applied correctly in context of NTLM authentication.
@ghostghost
added

community-contribution
Indicates that the PR has been added by a community member
area-System.Net.Security

labels
Jun 28, 2022
@ghost
ghost
commented
Jun 28, 2022

Copy link


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Tagging subscribers to this area: @dotnet/ncl, @vcsjones

See info in area-owners.md if you want to be subscribed.
Issue Details
Built on top of #71280, best reviewed commit by commit.
Firstly, it fixes an interoperability scenario for non-encrypted NTLM communication passed through NegotiateStream between Unix and Windows. It updates the NegotiateStreamPal.Encrypt/Decrypt Unix implementation to have the same quirk as the Windows implementation has.
Secondly, it fixes a bunch of bugs in the SmtpClient GSSAPI authentication and adds a loopback server test. This was also tested against a real Microsoft Exchange server to ensure that it works properly and that the encryption/decryption is applied correctly in context of NTLM authentication.
Author:filipnavara
Assignees:-
Labels:
area-System.Net.Security, community-contribution
Milestone:-
@filipnavarafilipnavara
mentioned this pull request
Jun 29, 2022
 Merged

@filipnavara
filipnavara
marked this pull request as ready for review
June 29, 2022 10:00
@filipnavara
filipnavara
requested a review
from wfurtJune 29, 2022 10:00
@filipnavara
Implement NTLM quirk in NegotiateStreamPal.Encrypt/Decrypt
a7dc399
NegotiateStream on non-encrypted connections with NTLM sends the
messages in a special `<signature token><plain text message>` format.
That's not something that gss_wrap/gss_unwrap would produce. It can be
produced through gss_get_mic/gss_verify_mic calls though so let's do
that.
@filipnavara
Remove MakeSignature/VerifySignature from SspiCli interop
9804db0
The method names were misleading since they wrapped the EncryptMessage
and DecryptMessage native APIs and not the MakeSignature/VerifySignature
APIs that also exist.
@filipnavara
Remove unused sequenceNumber parameters in NegotiateStreamPal.Encrypt…
c4c3200
…/Decrypt
The SSPI / GSSAPI providers keep track of the sequence numbers
themselves.
@filipnavara
Replace NTAuthentication.MakeSignature/VerifySignature with Wrap/Unwrap
6e634b9
This maps directly to the semantics of gss_wrap/gss_unwrap methods
that are used in many specifications. It replaces the misleading name
which in SSPI API is an equivalent of gss_get_mic/gss_verify_mic.
It also fixes the declaration to actually decode the buffers both
on Windows and Unix. In NTLM the content of the message is sealed
and needs to be decoded.
Note that previously on Unix the VerifySignature API didn't decode the
content. On Windows it did decode the content inside a buffer that was
passed as ReadOnlySpan<byte> but it didn't communicate back the offset
of the decoded data.
The SMTP GSSAPI authentication code was thus reading incorrect data.
In case the underlying authentication was Kerberos the data were
not encrypted and they were located at the beginning of the buffer
so it was not an issue. In case the underlying authentication was
NTLM it was looking at the NTLM signature token which luckily
happens to always start with the bytes 01 00 00 00. That exactly
matched the expected value by accident.
@filipnavara
Fix processing of last SMTP GSSAPI token
d801c84
The last token in the GSSAPI SASL authentication mechanism is a bit
mask that specifies the supported security protections offered by the
server and the maximum token size. The client is supposed to choose
one of the protections and reply back. Relax the check to actually
support servers that offer anything but "no protection". As long
as the server also offers no protection we can choose it.
@filipnavara
Update unit test to use the new Wrap/Unwrap APIs
c99f819
@filipnavara
Reset NTLM keys after successful Negotiate authentication
a8e835a
Updated the managed NTLM implementation and the fake servers to
implement the specification quirk:
MS-SPNG section 3.2.5.1 NTLM RC4 Key State for MechListMIC and First
Signed Message specifies that the RC4 sealing keys are reset back to
the initial state for the first message.
Since the managed implementation doesn't expose encryption yet it
didn't affect any observable behavior. Likewise the fake servers
didn't need this code path yet.
@filipnavara
Add GSSAPI authentication test to the loopback SMTP server
a57be6a
@filipnavara
Workaround forgssapi/gss-ntlmssp#77
67b12d9
@filipnavara
Expose the confidentiality flag from the native gss_wrap/unwrap APIs
5926042
wfurt
wfurt
approved these changes
Jun 29, 2022
View reviewed changes
@wfurtwfurt
left a comment


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LGTM.

cc: @SteveSyfuhs for any thoughts on the GSSAPI/SSPI changes.
@wfurt
wfurt
commented
Jun 29, 2022

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contributes to #19436
@wfurtwfurt
mentioned this pull request
Jun 30, 2022
 Merged

@wfurt
wfurt
merged commit ac9e1f9
into
dotnet:mainJun 30, 2022
@karelzkarelz
added this to the 7.0.0 milestone
Jul 19, 2022
@ghostghost
locked as resolved and limited conversation to collaborators
Aug 18, 2022
@filipnavara
filipnavara
deleted the

smtpauth2

branch
June 5, 2025 07:39
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, 'i');
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})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
Improve interoperability of NTLM encryption/decryption and authentication - #71373
Merged
wfurt merged 11 commits into
dotnet:mainfrom 
filipnavara:smtpauth2
Jun 30, 2022
Merged
Improve interoperability of NTLM encryption/decryption and authentication#71373
wfurt merged 11 commits into
dotnet:mainfrom 
filipnavara:smtpauth2
Conversation
@filipnavara
@filipnavarafilipnavara
commented
Jun 28, 2022•

edited

Loading

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Member
Best reviewed commit by commit.
Firstly, it fixes an interoperability scenario for non-encrypted NTLM communication passed through NegotiateStream between Unix and Windows. It updates the NegotiateStreamPal.Encrypt/Decrypt Unix implementation to have the same quirk as the Windows implementation has.
Secondly, it fixes a bunch of bugs in the SmtpClient GSSAPI authentication and adds a loopback server test. This was also tested against a real Microsoft Exchange server to ensure that it works properly and that the encryption/decryption is applied correctly in context of NTLM authentication.
@ghostghost
added

community-contribution
Indicates that the PR has been added by a community member
area-System.Net.Security

labels
Jun 28, 2022
@ghost
ghost
commented
Jun 28, 2022

Copy link


Copy Markdown

Tagging subscribers to this area: @dotnet/ncl, @vcsjones

See info in area-owners.md if you want to be subscribed.
Issue Details
Built on top of #71280, best reviewed commit by commit.
Firstly, it fixes an interoperability scenario for non-encrypted NTLM communication passed through NegotiateStream between Unix and Windows. It updates the NegotiateStreamPal.Encrypt/Decrypt Unix implementation to have the same quirk as the Windows implementation has.
Secondly, it fixes a bunch of bugs in the SmtpClient GSSAPI authentication and adds a loopback server test. This was also tested against a real Microsoft Exchange server to ensure that it works properly and that the encryption/decryption is applied correctly in context of NTLM authentication.
Author:filipnavara
Assignees:-
Labels:
area-System.Net.Security, community-contribution
Milestone:-
@filipnavarafilipnavara
mentioned this pull request
Jun 29, 2022
 Merged

@filipnavara
filipnavara
marked this pull request as ready for review
June 29, 2022 10:00
@filipnavara
filipnavara
requested a review
from wfurtJune 29, 2022 10:00
@filipnavara
Implement NTLM quirk in NegotiateStreamPal.Encrypt/Decrypt
a7dc399
NegotiateStream on non-encrypted connections with NTLM sends the
messages in a special `<signature token><plain text message>` format.
That's not something that gss_wrap/gss_unwrap would produce. It can be
produced through gss_get_mic/gss_verify_mic calls though so let's do
that.
@filipnavara
Remove MakeSignature/VerifySignature from SspiCli interop
9804db0
The method names were misleading since they wrapped the EncryptMessage
and DecryptMessage native APIs and not the MakeSignature/VerifySignature
APIs that also exist.
@filipnavara
Remove unused sequenceNumber parameters in NegotiateStreamPal.Encrypt…
c4c3200
…/Decrypt
The SSPI / GSSAPI providers keep track of the sequence numbers
themselves.
@filipnavara
Replace NTAuthentication.MakeSignature/VerifySignature with Wrap/Unwrap
6e634b9
This maps directly to the semantics of gss_wrap/gss_unwrap methods
that are used in many specifications. It replaces the misleading name
which in SSPI API is an equivalent of gss_get_mic/gss_verify_mic.
It also fixes the declaration to actually decode the buffers both
on Windows and Unix. In NTLM the content of the message is sealed
and needs to be decoded.
Note that previously on Unix the VerifySignature API didn't decode the
content. On Windows it did decode the content inside a buffer that was
passed as ReadOnlySpan<byte> but it didn't communicate back the offset
of the decoded data.
The SMTP GSSAPI authentication code was thus reading incorrect data.
In case the underlying authentication was Kerberos the data were
not encrypted and they were located at the beginning of the buffer
so it was not an issue. In case the underlying authentication was
NTLM it was looking at the NTLM signature token which luckily
happens to always start with the bytes 01 00 00 00. That exactly
matched the expected value by accident.
@filipnavara
Fix processing of last SMTP GSSAPI token
d801c84
The last token in the GSSAPI SASL authentication mechanism is a bit
mask that specifies the supported security protections offered by the
server and the maximum token size. The client is supposed to choose
one of the protections and reply back. Relax the check to actually
support servers that offer anything but "no protection". As long
as the server also offers no protection we can choose it.
@filipnavara
Update unit test to use the new Wrap/Unwrap APIs
c99f819
@filipnavara
Reset NTLM keys after successful Negotiate authentication
a8e835a
Updated the managed NTLM implementation and the fake servers to
implement the specification quirk:
MS-SPNG section 3.2.5.1 NTLM RC4 Key State for MechListMIC and First
Signed Message specifies that the RC4 sealing keys are reset back to
the initial state for the first message.
Since the managed implementation doesn't expose encryption yet it
didn't affect any observable behavior. Likewise the fake servers
didn't need this code path yet.
@filipnavara
Add GSSAPI authentication test to the loopback SMTP server
a57be6a
@filipnavara
Workaround forgssapi/gss-ntlmssp#77
67b12d9
@filipnavara
Expose the confidentiality flag from the native gss_wrap/unwrap APIs
5926042
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LGTM.

cc: @SteveSyfuhs for any thoughts on the GSSAPI/SSPI changes.
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contributes to #19436
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Improve interoperability of NTLM encryption/decryption and authentication - #71373
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wfurt merged 11 commits into
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filipnavara:smtpauth2
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Improve interoperability of NTLM encryption/decryption and authentication#71373
wfurt merged 11 commits into
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filipnavara:smtpauth2
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Best reviewed commit by commit.
Firstly, it fixes an interoperability scenario for non-encrypted NTLM communication passed through NegotiateStream between Unix and Windows. It updates the NegotiateStreamPal.Encrypt/Decrypt Unix implementation to have the same quirk as the Windows implementation has.
Secondly, it fixes a bunch of bugs in the SmtpClient GSSAPI authentication and adds a loopback server test. This was also tested against a real Microsoft Exchange server to ensure that it works properly and that the encryption/decryption is applied correctly in context of NTLM authentication.
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Issue Details
Built on top of #71280, best reviewed commit by commit.
Firstly, it fixes an interoperability scenario for non-encrypted NTLM communication passed through NegotiateStream between Unix and Windows. It updates the NegotiateStreamPal.Encrypt/Decrypt Unix implementation to have the same quirk as the Windows implementation has.
Secondly, it fixes a bunch of bugs in the SmtpClient GSSAPI authentication and adds a loopback server test. This was also tested against a real Microsoft Exchange server to ensure that it works properly and that the encryption/decryption is applied correctly in context of NTLM authentication.
Author:filipnavara
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Labels:
area-System.Net.Security, community-contribution
Milestone:-
@filipnavarafilipnavara
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from wfurtJune 29, 2022 10:00
@filipnavara
Implement NTLM quirk in NegotiateStreamPal.Encrypt/Decrypt
a7dc399
NegotiateStream on non-encrypted connections with NTLM sends the
messages in a special `<signature token><plain text message>` format.
That's not something that gss_wrap/gss_unwrap would produce. It can be
produced through gss_get_mic/gss_verify_mic calls though so let's do
that.
@filipnavara
Remove MakeSignature/VerifySignature from SspiCli interop
9804db0
The method names were misleading since they wrapped the EncryptMessage
and DecryptMessage native APIs and not the MakeSignature/VerifySignature
APIs that also exist.
@filipnavara
Remove unused sequenceNumber parameters in NegotiateStreamPal.Encrypt…
c4c3200
…/Decrypt
The SSPI / GSSAPI providers keep track of the sequence numbers
themselves.
@filipnavara
Replace NTAuthentication.MakeSignature/VerifySignature with Wrap/Unwrap
6e634b9
This maps directly to the semantics of gss_wrap/gss_unwrap methods
that are used in many specifications. It replaces the misleading name
which in SSPI API is an equivalent of gss_get_mic/gss_verify_mic.
It also fixes the declaration to actually decode the buffers both
on Windows and Unix. In NTLM the content of the message is sealed
and needs to be decoded.
Note that previously on Unix the VerifySignature API didn't decode the
content. On Windows it did decode the content inside a buffer that was
passed as ReadOnlySpan<byte> but it didn't communicate back the offset
of the decoded data.
The SMTP GSSAPI authentication code was thus reading incorrect data.
In case the underlying authentication was Kerberos the data were
not encrypted and they were located at the beginning of the buffer
so it was not an issue. In case the underlying authentication was
NTLM it was looking at the NTLM signature token which luckily
happens to always start with the bytes 01 00 00 00. That exactly
matched the expected value by accident.
@filipnavara
Fix processing of last SMTP GSSAPI token
d801c84
The last token in the GSSAPI SASL authentication mechanism is a bit
mask that specifies the supported security protections offered by the
server and the maximum token size. The client is supposed to choose
one of the protections and reply back. Relax the check to actually
support servers that offer anything but "no protection". As long
as the server also offers no protection we can choose it.
@filipnavara
Update unit test to use the new Wrap/Unwrap APIs
c99f819
@filipnavara
Reset NTLM keys after successful Negotiate authentication
a8e835a
Updated the managed NTLM implementation and the fake servers to
implement the specification quirk:
MS-SPNG section 3.2.5.1 NTLM RC4 Key State for MechListMIC and First
Signed Message specifies that the RC4 sealing keys are reset back to
the initial state for the first message.
Since the managed implementation doesn't expose encryption yet it
didn't affect any observable behavior. Likewise the fake servers
didn't need this code path yet.
@filipnavara
Add GSSAPI authentication test to the loopback SMTP server
a57be6a
@filipnavara
Workaround forgssapi/gss-ntlmssp#77
67b12d9
@filipnavara
Expose the confidentiality flag from the native gss_wrap/unwrap APIs
5926042
wfurt
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LGTM.

cc: @SteveSyfuhs for any thoughts on the GSSAPI/SSPI changes.
@wfurt
wfurt
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Jun 29, 2022

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contributes to #19436
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@karelzkarelz
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Jul 19, 2022
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Aug 18, 2022
@filipnavara
filipnavara
deleted the

smtpauth2

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June 5, 2025 07:39
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