curl/lib/vauth/digest_sspi.c
Gisle Vanem 61825be02b vtls: select ssl backend case-insensitive (follow-up)
- Do a case-insensitive comparison of CURL_SSL_BACKEND env as well.

- Change Curl_strcasecompare calls to strcasecompare
  (maps to the former but shorter).

Follow-up to c290b8f.

Bug: https://github.com/curl/curl/commit/c290b8f#commitcomment-24094313

Co-authored-by: Jay Satiro
2017-09-06 02:27:33 -04:00

670 lines
20 KiB
C

/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 2014 - 2016, Steve Holme, <steve_holme@hotmail.com>.
* Copyright (C) 2015 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.haxx.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* RFC2831 DIGEST-MD5 authentication
*
***************************************************************************/
#include "curl_setup.h"
#if defined(USE_WINDOWS_SSPI) && !defined(CURL_DISABLE_CRYPTO_AUTH)
#include <curl/curl.h>
#include "vauth/vauth.h"
#include "vauth/digest.h"
#include "urldata.h"
#include "curl_base64.h"
#include "warnless.h"
#include "curl_multibyte.h"
#include "sendf.h"
#include "strdup.h"
#include "strcase.h"
/* The last #include files should be: */
#include "curl_memory.h"
#include "memdebug.h"
/*
* Curl_auth_is_digest_supported()
*
* This is used to evaluate if DIGEST is supported.
*
* Parameters: None
*
* Returns TRUE if DIGEST is supported by Windows SSPI.
*/
bool Curl_auth_is_digest_supported(void)
{
PSecPkgInfo SecurityPackage;
SECURITY_STATUS status;
/* Query the security package for Digest */
status = s_pSecFn->QuerySecurityPackageInfo((TCHAR *) TEXT(SP_NAME_DIGEST),
&SecurityPackage);
return (status == SEC_E_OK ? TRUE : FALSE);
}
/*
* Curl_auth_create_digest_md5_message()
*
* This is used to generate an already encoded DIGEST-MD5 response message
* ready for sending to the recipient.
*
* Parameters:
*
* data [in] - The session handle.
* chlg64 [in] - The base64 encoded challenge message.
* userp [in] - The user name in the format User or Domain\User.
* passdwp [in] - The user's password.
* service [in] - The service type such as http, smtp, pop or imap.
* outptr [in/out] - The address where a pointer to newly allocated memory
* holding the result will be stored upon completion.
* outlen [out] - The length of the output message.
*
* Returns CURLE_OK on success.
*/
CURLcode Curl_auth_create_digest_md5_message(struct Curl_easy *data,
const char *chlg64,
const char *userp,
const char *passwdp,
const char *service,
char **outptr, size_t *outlen)
{
CURLcode result = CURLE_OK;
TCHAR *spn = NULL;
size_t chlglen = 0;
size_t token_max = 0;
unsigned char *input_token = NULL;
unsigned char *output_token = NULL;
CredHandle credentials;
CtxtHandle context;
PSecPkgInfo SecurityPackage;
SEC_WINNT_AUTH_IDENTITY identity;
SEC_WINNT_AUTH_IDENTITY *p_identity;
SecBuffer chlg_buf;
SecBuffer resp_buf;
SecBufferDesc chlg_desc;
SecBufferDesc resp_desc;
SECURITY_STATUS status;
unsigned long attrs;
TimeStamp expiry; /* For Windows 9x compatibility of SSPI calls */
/* Decode the base-64 encoded challenge message */
if(strlen(chlg64) && *chlg64 != '=') {
result = Curl_base64_decode(chlg64, &input_token, &chlglen);
if(result)
return result;
}
/* Ensure we have a valid challenge message */
if(!input_token) {
infof(data, "DIGEST-MD5 handshake failure (empty challenge message)\n");
return CURLE_BAD_CONTENT_ENCODING;
}
/* Query the security package for DigestSSP */
status = s_pSecFn->QuerySecurityPackageInfo((TCHAR *) TEXT(SP_NAME_DIGEST),
&SecurityPackage);
if(status != SEC_E_OK) {
free(input_token);
return CURLE_NOT_BUILT_IN;
}
token_max = SecurityPackage->cbMaxToken;
/* Release the package buffer as it is not required anymore */
s_pSecFn->FreeContextBuffer(SecurityPackage);
/* Allocate our response buffer */
output_token = malloc(token_max);
if(!output_token) {
free(input_token);
return CURLE_OUT_OF_MEMORY;
}
/* Generate our SPN */
spn = Curl_auth_build_spn(service, data->easy_conn->host.name, NULL);
if(!spn) {
free(output_token);
free(input_token);
return CURLE_OUT_OF_MEMORY;
}
if(userp && *userp) {
/* Populate our identity structure */
result = Curl_create_sspi_identity(userp, passwdp, &identity);
if(result) {
free(spn);
free(output_token);
free(input_token);
return result;
}
/* Allow proper cleanup of the identity structure */
p_identity = &identity;
}
else
/* Use the current Windows user */
p_identity = NULL;
/* Acquire our credentials handle */
status = s_pSecFn->AcquireCredentialsHandle(NULL,
(TCHAR *) TEXT(SP_NAME_DIGEST),
SECPKG_CRED_OUTBOUND, NULL,
p_identity, NULL, NULL,
&credentials, &expiry);
if(status != SEC_E_OK) {
Curl_sspi_free_identity(p_identity);
free(spn);
free(output_token);
free(input_token);
return CURLE_LOGIN_DENIED;
}
/* 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 = input_token;
chlg_buf.cbBuffer = curlx_uztoul(chlglen);
/* Setup the response "output" security buffer */
resp_desc.ulVersion = SECBUFFER_VERSION;
resp_desc.cBuffers = 1;
resp_desc.pBuffers = &resp_buf;
resp_buf.BufferType = SECBUFFER_TOKEN;
resp_buf.pvBuffer = output_token;
resp_buf.cbBuffer = curlx_uztoul(token_max);
/* Generate our response message */
status = s_pSecFn->InitializeSecurityContext(&credentials, NULL, spn,
0, 0, 0, &chlg_desc, 0,
&context, &resp_desc, &attrs,
&expiry);
if(status == SEC_I_COMPLETE_NEEDED ||
status == SEC_I_COMPLETE_AND_CONTINUE)
s_pSecFn->CompleteAuthToken(&credentials, &resp_desc);
else if(status != SEC_E_OK && status != SEC_I_CONTINUE_NEEDED) {
s_pSecFn->FreeCredentialsHandle(&credentials);
Curl_sspi_free_identity(p_identity);
free(spn);
free(output_token);
free(input_token);
return CURLE_RECV_ERROR;
}
/* Base64 encode the response */
result = Curl_base64_encode(data, (char *) output_token, resp_buf.cbBuffer,
outptr, outlen);
/* Free our handles */
s_pSecFn->DeleteSecurityContext(&context);
s_pSecFn->FreeCredentialsHandle(&credentials);
/* Free the identity structure */
Curl_sspi_free_identity(p_identity);
/* Free the SPN */
free(spn);
/* Free the response buffer */
free(output_token);
/* Free the decoded challenge message */
free(input_token);
return result;
}
/*
* Curl_override_sspi_http_realm()
*
* This is used to populate the domain in a SSPI identity structure
* The realm is extracted from the challenge message and used as the
* domain if it is not already explicitly set.
*
* Parameters:
*
* chlg [in] - The challenge message.
* identity [in/out] - The identity structure.
*
* Returns CURLE_OK on success.
*/
CURLcode Curl_override_sspi_http_realm(const char *chlg,
SEC_WINNT_AUTH_IDENTITY *identity)
{
xcharp_u domain, dup_domain;
/* If domain is blank or unset, check challenge message for realm */
if(!identity->Domain || !identity->DomainLength) {
for(;;) {
char value[DIGEST_MAX_VALUE_LENGTH];
char content[DIGEST_MAX_CONTENT_LENGTH];
/* Pass all additional spaces here */
while(*chlg && ISSPACE(*chlg))
chlg++;
/* Extract a value=content pair */
if(Curl_auth_digest_get_pair(chlg, value, content, &chlg)) {
if(strcasecompare(value, "realm")) {
/* Setup identity's domain and length */
domain.tchar_ptr = Curl_convert_UTF8_to_tchar((char *) content);
if(!domain.tchar_ptr)
return CURLE_OUT_OF_MEMORY;
dup_domain.tchar_ptr = _tcsdup(domain.tchar_ptr);
if(!dup_domain.tchar_ptr) {
Curl_unicodefree(domain.tchar_ptr);
return CURLE_OUT_OF_MEMORY;
}
free(identity->Domain);
identity->Domain = dup_domain.tbyte_ptr;
identity->DomainLength = curlx_uztoul(_tcslen(dup_domain.tchar_ptr));
dup_domain.tchar_ptr = NULL;
Curl_unicodefree(domain.tchar_ptr);
}
else {
/* Unknown specifier, ignore it! */
}
}
else
break; /* We're done here */
/* Pass all additional spaces here */
while(*chlg && ISSPACE(*chlg))
chlg++;
/* Allow the list to be comma-separated */
if(',' == *chlg)
chlg++;
}
}
return CURLE_OK;
}
/*
* Curl_auth_decode_digest_http_message()
*
* This is used to decode a HTTP DIGEST challenge message into the separate
* attributes.
*
* Parameters:
*
* chlg [in] - The challenge message.
* digest [in/out] - The digest data struct being used and modified.
*
* Returns CURLE_OK on success.
*/
CURLcode Curl_auth_decode_digest_http_message(const char *chlg,
struct digestdata *digest)
{
size_t chlglen = strlen(chlg);
/* We had an input token before so if there's another one now that means we
provided bad credentials in the previous request or it's stale. */
if(digest->input_token) {
bool stale = false;
const char *p = chlg;
/* Check for the 'stale' directive */
for(;;) {
char value[DIGEST_MAX_VALUE_LENGTH];
char content[DIGEST_MAX_CONTENT_LENGTH];
while(*p && ISSPACE(*p))
p++;
if(!Curl_auth_digest_get_pair(p, value, content, &p))
break;
if(strcasecompare(value, "stale") &&
strcasecompare(content, "true")) {
stale = true;
break;
}
while(*p && ISSPACE(*p))
p++;
if(',' == *p)
p++;
}
if(stale)
Curl_auth_digest_cleanup(digest);
else
return CURLE_LOGIN_DENIED;
}
/* Store the challenge for use later */
digest->input_token = (BYTE *) Curl_memdup(chlg, chlglen + 1);
if(!digest->input_token)
return CURLE_OUT_OF_MEMORY;
digest->input_token_len = chlglen;
return CURLE_OK;
}
/*
* Curl_auth_create_digest_http_message()
*
* This is used to generate a HTTP DIGEST response message ready for sending
* to the recipient.
*
* Parameters:
*
* data [in] - The session handle.
* userp [in] - The user name in the format User or Domain\User.
* passdwp [in] - The user's password.
* request [in] - The HTTP request.
* uripath [in] - The path of the HTTP uri.
* digest [in/out] - The digest data struct being used and modified.
* outptr [in/out] - The address where a pointer to newly allocated memory
* holding the result will be stored upon completion.
* outlen [out] - The length of the output message.
*
* Returns CURLE_OK on success.
*/
CURLcode Curl_auth_create_digest_http_message(struct Curl_easy *data,
const char *userp,
const char *passwdp,
const unsigned char *request,
const unsigned char *uripath,
struct digestdata *digest,
char **outptr, size_t *outlen)
{
size_t token_max;
char *resp;
BYTE *output_token;
size_t output_token_len = 0;
PSecPkgInfo SecurityPackage;
SecBuffer chlg_buf[5];
SecBufferDesc chlg_desc;
SECURITY_STATUS status;
(void) data;
/* Query the security package for DigestSSP */
status = s_pSecFn->QuerySecurityPackageInfo((TCHAR *) TEXT(SP_NAME_DIGEST),
&SecurityPackage);
if(status != SEC_E_OK)
return CURLE_NOT_BUILT_IN;
token_max = SecurityPackage->cbMaxToken;
/* Release the package buffer as it is not required anymore */
s_pSecFn->FreeContextBuffer(SecurityPackage);
/* Allocate the output buffer according to the max token size as indicated
by the security package */
output_token = malloc(token_max);
if(!output_token) {
return CURLE_OUT_OF_MEMORY;
}
/* If the user/passwd that was used to make the identity for http_context
has changed then delete that context. */
if((userp && !digest->user) || (!userp && digest->user) ||
(passwdp && !digest->passwd) || (!passwdp && digest->passwd) ||
(userp && digest->user && strcmp(userp, digest->user)) ||
(passwdp && digest->passwd && strcmp(passwdp, digest->passwd))) {
if(digest->http_context) {
s_pSecFn->DeleteSecurityContext(digest->http_context);
Curl_safefree(digest->http_context);
}
Curl_safefree(digest->user);
Curl_safefree(digest->passwd);
}
if(digest->http_context) {
chlg_desc.ulVersion = SECBUFFER_VERSION;
chlg_desc.cBuffers = 5;
chlg_desc.pBuffers = chlg_buf;
chlg_buf[0].BufferType = SECBUFFER_TOKEN;
chlg_buf[0].pvBuffer = NULL;
chlg_buf[0].cbBuffer = 0;
chlg_buf[1].BufferType = SECBUFFER_PKG_PARAMS;
chlg_buf[1].pvBuffer = (void *) request;
chlg_buf[1].cbBuffer = curlx_uztoul(strlen((const char *) request));
chlg_buf[2].BufferType = SECBUFFER_PKG_PARAMS;
chlg_buf[2].pvBuffer = (void *) uripath;
chlg_buf[2].cbBuffer = curlx_uztoul(strlen((const char *) uripath));
chlg_buf[3].BufferType = SECBUFFER_PKG_PARAMS;
chlg_buf[3].pvBuffer = NULL;
chlg_buf[3].cbBuffer = 0;
chlg_buf[4].BufferType = SECBUFFER_PADDING;
chlg_buf[4].pvBuffer = output_token;
chlg_buf[4].cbBuffer = curlx_uztoul(token_max);
status = s_pSecFn->MakeSignature(digest->http_context, 0, &chlg_desc, 0);
if(status == SEC_E_OK)
output_token_len = chlg_buf[4].cbBuffer;
else { /* delete the context so a new one can be made */
infof(data, "digest_sspi: MakeSignature failed, error 0x%08lx\n",
(long)status);
s_pSecFn->DeleteSecurityContext(digest->http_context);
Curl_safefree(digest->http_context);
}
}
if(!digest->http_context) {
CredHandle credentials;
SEC_WINNT_AUTH_IDENTITY identity;
SEC_WINNT_AUTH_IDENTITY *p_identity;
SecBuffer resp_buf;
SecBufferDesc resp_desc;
unsigned long attrs;
TimeStamp expiry; /* For Windows 9x compatibility of SSPI calls */
TCHAR *spn;
/* free the copy of user/passwd used to make the previous identity */
Curl_safefree(digest->user);
Curl_safefree(digest->passwd);
if(userp && *userp) {
/* Populate our identity structure */
if(Curl_create_sspi_identity(userp, passwdp, &identity)) {
free(output_token);
return CURLE_OUT_OF_MEMORY;
}
/* Populate our identity domain */
if(Curl_override_sspi_http_realm((const char *) digest->input_token,
&identity)) {
free(output_token);
return CURLE_OUT_OF_MEMORY;
}
/* Allow proper cleanup of the identity structure */
p_identity = &identity;
}
else
/* Use the current Windows user */
p_identity = NULL;
if(userp) {
digest->user = strdup(userp);
if(!digest->user) {
free(output_token);
return CURLE_OUT_OF_MEMORY;
}
}
if(passwdp) {
digest->passwd = strdup(passwdp);
if(!digest->passwd) {
free(output_token);
Curl_safefree(digest->user);
return CURLE_OUT_OF_MEMORY;
}
}
/* Acquire our credentials handle */
status = s_pSecFn->AcquireCredentialsHandle(NULL,
(TCHAR *) TEXT(SP_NAME_DIGEST),
SECPKG_CRED_OUTBOUND, NULL,
p_identity, NULL, NULL,
&credentials, &expiry);
if(status != SEC_E_OK) {
Curl_sspi_free_identity(p_identity);
free(output_token);
return CURLE_LOGIN_DENIED;
}
/* Setup the challenge "input" security buffer if present */
chlg_desc.ulVersion = SECBUFFER_VERSION;
chlg_desc.cBuffers = 3;
chlg_desc.pBuffers = chlg_buf;
chlg_buf[0].BufferType = SECBUFFER_TOKEN;
chlg_buf[0].pvBuffer = digest->input_token;
chlg_buf[0].cbBuffer = curlx_uztoul(digest->input_token_len);
chlg_buf[1].BufferType = SECBUFFER_PKG_PARAMS;
chlg_buf[1].pvBuffer = (void *) request;
chlg_buf[1].cbBuffer = curlx_uztoul(strlen((const char *) request));
chlg_buf[2].BufferType = SECBUFFER_PKG_PARAMS;
chlg_buf[2].pvBuffer = NULL;
chlg_buf[2].cbBuffer = 0;
/* Setup the response "output" security buffer */
resp_desc.ulVersion = SECBUFFER_VERSION;
resp_desc.cBuffers = 1;
resp_desc.pBuffers = &resp_buf;
resp_buf.BufferType = SECBUFFER_TOKEN;
resp_buf.pvBuffer = output_token;
resp_buf.cbBuffer = curlx_uztoul(token_max);
spn = Curl_convert_UTF8_to_tchar((char *) uripath);
if(!spn) {
s_pSecFn->FreeCredentialsHandle(&credentials);
Curl_sspi_free_identity(p_identity);
free(output_token);
return CURLE_OUT_OF_MEMORY;
}
/* Allocate our new context handle */
digest->http_context = calloc(1, sizeof(CtxtHandle));
if(!digest->http_context)
return CURLE_OUT_OF_MEMORY;
/* Generate our response message */
status = s_pSecFn->InitializeSecurityContext(&credentials, NULL,
spn,
ISC_REQ_USE_HTTP_STYLE, 0, 0,
&chlg_desc, 0,
digest->http_context,
&resp_desc, &attrs, &expiry);
Curl_unicodefree(spn);
if(status == SEC_I_COMPLETE_NEEDED ||
status == SEC_I_COMPLETE_AND_CONTINUE)
s_pSecFn->CompleteAuthToken(&credentials, &resp_desc);
else if(status != SEC_E_OK && status != SEC_I_CONTINUE_NEEDED) {
s_pSecFn->FreeCredentialsHandle(&credentials);
Curl_sspi_free_identity(p_identity);
free(output_token);
Curl_safefree(digest->http_context);
return CURLE_OUT_OF_MEMORY;
}
output_token_len = resp_buf.cbBuffer;
s_pSecFn->FreeCredentialsHandle(&credentials);
Curl_sspi_free_identity(p_identity);
}
resp = malloc(output_token_len + 1);
if(!resp) {
free(output_token);
return CURLE_OUT_OF_MEMORY;
}
/* Copy the generated response */
memcpy(resp, output_token, output_token_len);
resp[output_token_len] = 0;
/* Return the response */
*outptr = resp;
*outlen = output_token_len;
/* Free the response buffer */
free(output_token);
return CURLE_OK;
}
/*
* Curl_auth_digest_cleanup()
*
* This is used to clean up the digest specific data.
*
* Parameters:
*
* digest [in/out] - The digest data struct being cleaned up.
*
*/
void Curl_auth_digest_cleanup(struct digestdata *digest)
{
/* Free the input token */
Curl_safefree(digest->input_token);
/* Reset any variables */
digest->input_token_len = 0;
/* Delete security context */
if(digest->http_context) {
s_pSecFn->DeleteSecurityContext(digest->http_context);
Curl_safefree(digest->http_context);
}
/* Free the copy of user/passwd used to make the identity for http_context */
Curl_safefree(digest->user);
Curl_safefree(digest->passwd);
}
#endif /* USE_WINDOWS_SSPI && !CURL_DISABLE_CRYPTO_AUTH */