spnego_sspi: add support for channel binding

Attempt to add support for Secure Channel binding when negotiate
authentication is used. The problem to solve is that by default IIS
accepts channel binding and curl doesn't utilise them. The result was a
401 response. Scope affects only the Schannel(winssl)-SSPI combination.

Fixes https://github.com/curl/curl/issues/3503
Closes https://github.com/curl/curl/pull/3509
This commit is contained in:
georgeok 2019-01-29 18:26:31 +01:00 committed by Marcel Raad
parent 463f16d188
commit a730432e59
No known key found for this signature in database
GPG key ID: 33C416EFAE4D6F02
5 changed files with 49 additions and 8 deletions

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@ -92,7 +92,7 @@ CURLcode Curl_auth_decode_spnego_message(struct Curl_easy *data,
size_t chlglen = 0;
unsigned char *chlg = NULL;
PSecPkgInfo SecurityPackage;
SecBuffer chlg_buf;
SecBuffer chlg_buf[2];
SecBuffer resp_buf;
SecBufferDesc chlg_desc;
SecBufferDesc resp_desc;
@ -189,12 +189,39 @@ CURLcode Curl_auth_decode_spnego_message(struct Curl_easy *data,
}
/* Setup the challenge "input" security buffer */
chlg_desc.ulVersion = SECBUFFER_VERSION;
chlg_desc.cBuffers = 1;
chlg_desc.pBuffers = &chlg_buf;
chlg_buf.BufferType = SECBUFFER_TOKEN;
chlg_buf.pvBuffer = chlg;
chlg_buf.cbBuffer = curlx_uztoul(chlglen);
chlg_desc.ulVersion = SECBUFFER_VERSION;
chlg_desc.cBuffers = 1;
chlg_desc.pBuffers = &chlg_buf[0];
chlg_buf[0].BufferType = SECBUFFER_TOKEN;
chlg_buf[0].pvBuffer = chlg;
chlg_buf[0].cbBuffer = curlx_uztoul(chlglen);
#ifdef SECPKG_ATTR_ENDPOINT_BINDINGS
/* ssl context comes from Schannel.
* When extended protection is used in IIS server,
* we have to pass a second SecBuffer to the SecBufferDesc
* otherwise IIS will not pass the authentication (401 response).
* Minimum supported version is Windows 7.
* https://docs.microsoft.com/en-us/security-updates
* /SecurityAdvisories/2009/973811
*/
if(nego->sslContext) {
SEC_CHANNEL_BINDINGS channelBindings;
SecPkgContext_Bindings pkgBindings;
pkgBindings.Bindings = &channelBindings;
nego->status = s_pSecFn->QueryContextAttributes(
nego->sslContext,
SECPKG_ATTR_ENDPOINT_BINDINGS,
&pkgBindings
);
if(nego->status == SEC_E_OK) {
chlg_desc.cBuffers++;
chlg_buf[1].BufferType = SECBUFFER_CHANNEL_BINDINGS;
chlg_buf[1].cbBuffer = pkgBindings.BindingsLength;
chlg_buf[1].pvBuffer = pkgBindings.Bindings;
}
}
#endif
}
/* Setup the response "output" security buffer */