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curl/lib/socks_gssapi.c

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/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 2009, Markus Moeller, <markus_moeller@compuserve.com>
* Copyright (C) 2012 - 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.
*
***************************************************************************/
build: fix circular header inclusion with other packages This commit renames lib/setup.h to lib/curl_setup.h and renames lib/setup_once.h to lib/curl_setup_once.h. Removes the need and usage of a header inclusion guard foreign to libcurl. [1] Removes the need and presence of an alarming notice we carried in old setup_once.h [2] ---------------------------------------- 1 - lib/setup_once.h used __SETUP_ONCE_H macro as header inclusion guard up to commit ec691ca3 which changed this to HEADER_CURL_SETUP_ONCE_H, this single inclusion guard is enough to ensure that inclusion of lib/setup_once.h done from lib/setup.h is only done once. Additionally lib/setup.h has always used __SETUP_ONCE_H macro to protect inclusion of setup_once.h even after commit ec691ca3, this was to avoid a circular header inclusion triggered when building a c-ares enabled version with c-ares sources available which also has a setup_once.h header. Commit ec691ca3 exposes the real nature of __SETUP_ONCE_H usage in lib/setup.h, it is a header inclusion guard foreign to libcurl belonging to c-ares's setup_once.h The renaming this commit does, fixes the circular header inclusion, and as such removes the need and usage of a header inclusion guard foreign to libcurl. Macro __SETUP_ONCE_H no longer used in libcurl. 2 - Due to the circular interdependency of old lib/setup_once.h and the c-ares setup_once.h header, old file lib/setup_once.h has carried back from 2006 up to now days an alarming and prominent notice about the need of keeping libcurl's and c-ares's setup_once.h in sync. Given that this commit fixes the circular interdependency, the need and presence of mentioned notice is removed. All mentioned interdependencies come back from now old days when the c-ares project lived inside a curl subdirectory. This commit removes last traces of such fact.
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#include "curl_setup.h"
#if defined(HAVE_GSSAPI) && !defined(CURL_DISABLE_PROXY)
#include "curl_gssapi.h"
#include "urldata.h"
#include "sendf.h"
#include "connect.h"
#include "timeval.h"
#include "socks.h"
#include "warnless.h"
/* The last 3 #include files should be in this order */
#include "curl_printf.h"
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#include "curl_memory.h"
#include "memdebug.h"
static gss_ctx_id_t gss_context = GSS_C_NO_CONTEXT;
/*
* Helper GSS-API error functions.
*/
static int check_gss_err(struct Curl_easy *data,
OM_uint32 major_status,
OM_uint32 minor_status,
const char *function)
{
if(GSS_ERROR(major_status)) {
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OM_uint32 maj_stat, min_stat;
OM_uint32 msg_ctx = 0;
gss_buffer_desc status_string;
char buf[1024];
size_t len;
len = 0;
msg_ctx = 0;
while(!msg_ctx) {
/* convert major status code (GSS-API error) to text */
maj_stat = gss_display_status(&min_stat, major_status,
GSS_C_GSS_CODE,
GSS_C_NULL_OID,
&msg_ctx, &status_string);
if(maj_stat == GSS_S_COMPLETE) {
if(sizeof(buf) > len + status_string.length + 1) {
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strcpy(buf + len, (char *) status_string.value);
len += status_string.length;
}
gss_release_buffer(&min_stat, &status_string);
break;
}
gss_release_buffer(&min_stat, &status_string);
}
if(sizeof(buf) > len + 3) {
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strcpy(buf + len, ".\n");
len += 2;
}
msg_ctx = 0;
while(!msg_ctx) {
/* convert minor status code (underlying routine error) to text */
maj_stat = gss_display_status(&min_stat, minor_status,
GSS_C_MECH_CODE,
GSS_C_NULL_OID,
&msg_ctx, &status_string);
if(maj_stat == GSS_S_COMPLETE) {
if(sizeof(buf) > len + status_string.length)
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strcpy(buf + len, (char *) status_string.value);
gss_release_buffer(&min_stat, &status_string);
break;
}
gss_release_buffer(&min_stat, &status_string);
}
failf(data, "GSS-API error: %s failed:\n%s", function, buf);
return 1;
}
return 0;
}
CURLcode Curl_SOCKS5_gssapi_negotiate(int sockindex,
struct connectdata *conn)
{
struct Curl_easy *data = conn->data;
curl_socket_t sock = conn->sock[sockindex];
CURLcode code;
ssize_t actualread;
ssize_t written;
int result;
OM_uint32 gss_major_status, gss_minor_status, gss_status;
OM_uint32 gss_ret_flags;
int gss_conf_state, gss_enc;
gss_buffer_desc service = GSS_C_EMPTY_BUFFER;
gss_buffer_desc gss_send_token = GSS_C_EMPTY_BUFFER;
gss_buffer_desc gss_recv_token = GSS_C_EMPTY_BUFFER;
gss_buffer_desc gss_w_token = GSS_C_EMPTY_BUFFER;
gss_buffer_desc* gss_token = GSS_C_NO_BUFFER;
gss_name_t server = GSS_C_NO_NAME;
gss_name_t gss_client_name = GSS_C_NO_NAME;
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unsigned short us_length;
char *user = NULL;
unsigned char socksreq[4]; /* room for GSS-API exchange header only */
const char *serviceptr = data->set.str[STRING_PROXY_SERVICE_NAME] ?
data->set.str[STRING_PROXY_SERVICE_NAME] : "rcmd";
proxy: Support HTTPS proxy and SOCKS+HTTP(s) * HTTPS proxies: An HTTPS proxy receives all transactions over an SSL/TLS connection. Once a secure connection with the proxy is established, the user agent uses the proxy as usual, including sending CONNECT requests to instruct the proxy to establish a [usually secure] TCP tunnel with an origin server. HTTPS proxies protect nearly all aspects of user-proxy communications as opposed to HTTP proxies that receive all requests (including CONNECT requests) in vulnerable clear text. With HTTPS proxies, it is possible to have two concurrent _nested_ SSL/TLS sessions: the "outer" one between the user agent and the proxy and the "inner" one between the user agent and the origin server (through the proxy). This change adds supports for such nested sessions as well. A secure connection with a proxy requires its own set of the usual SSL options (their actual descriptions differ and need polishing, see TODO): --proxy-cacert FILE CA certificate to verify peer against --proxy-capath DIR CA directory to verify peer against --proxy-cert CERT[:PASSWD] Client certificate file and password --proxy-cert-type TYPE Certificate file type (DER/PEM/ENG) --proxy-ciphers LIST SSL ciphers to use --proxy-crlfile FILE Get a CRL list in PEM format from the file --proxy-insecure Allow connections to proxies with bad certs --proxy-key KEY Private key file name --proxy-key-type TYPE Private key file type (DER/PEM/ENG) --proxy-pass PASS Pass phrase for the private key --proxy-ssl-allow-beast Allow security flaw to improve interop --proxy-sslv2 Use SSLv2 --proxy-sslv3 Use SSLv3 --proxy-tlsv1 Use TLSv1 --proxy-tlsuser USER TLS username --proxy-tlspassword STRING TLS password --proxy-tlsauthtype STRING TLS authentication type (default SRP) All --proxy-foo options are independent from their --foo counterparts, except --proxy-crlfile which defaults to --crlfile and --proxy-capath which defaults to --capath. Curl now also supports %{proxy_ssl_verify_result} --write-out variable, similar to the existing %{ssl_verify_result} variable. Supported backends: OpenSSL, GnuTLS, and NSS. * A SOCKS proxy + HTTP/HTTPS proxy combination: If both --socks* and --proxy options are given, Curl first connects to the SOCKS proxy and then connects (through SOCKS) to the HTTP or HTTPS proxy. TODO: Update documentation for the new APIs and --proxy-* options. Look for "Added in 7.XXX" marks.
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const size_t serviceptr_length = strlen(serviceptr);
/* GSS-API request looks like
* +----+------+-----+----------------+
* |VER | MTYP | LEN | TOKEN |
* +----+------+----------------------+
* | 1 | 1 | 2 | up to 2^16 - 1 |
* +----+------+-----+----------------+
*/
/* prepare service name */
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if(strchr(serviceptr, '/')) {
proxy: Support HTTPS proxy and SOCKS+HTTP(s) * HTTPS proxies: An HTTPS proxy receives all transactions over an SSL/TLS connection. Once a secure connection with the proxy is established, the user agent uses the proxy as usual, including sending CONNECT requests to instruct the proxy to establish a [usually secure] TCP tunnel with an origin server. HTTPS proxies protect nearly all aspects of user-proxy communications as opposed to HTTP proxies that receive all requests (including CONNECT requests) in vulnerable clear text. With HTTPS proxies, it is possible to have two concurrent _nested_ SSL/TLS sessions: the "outer" one between the user agent and the proxy and the "inner" one between the user agent and the origin server (through the proxy). This change adds supports for such nested sessions as well. A secure connection with a proxy requires its own set of the usual SSL options (their actual descriptions differ and need polishing, see TODO): --proxy-cacert FILE CA certificate to verify peer against --proxy-capath DIR CA directory to verify peer against --proxy-cert CERT[:PASSWD] Client certificate file and password --proxy-cert-type TYPE Certificate file type (DER/PEM/ENG) --proxy-ciphers LIST SSL ciphers to use --proxy-crlfile FILE Get a CRL list in PEM format from the file --proxy-insecure Allow connections to proxies with bad certs --proxy-key KEY Private key file name --proxy-key-type TYPE Private key file type (DER/PEM/ENG) --proxy-pass PASS Pass phrase for the private key --proxy-ssl-allow-beast Allow security flaw to improve interop --proxy-sslv2 Use SSLv2 --proxy-sslv3 Use SSLv3 --proxy-tlsv1 Use TLSv1 --proxy-tlsuser USER TLS username --proxy-tlspassword STRING TLS password --proxy-tlsauthtype STRING TLS authentication type (default SRP) All --proxy-foo options are independent from their --foo counterparts, except --proxy-crlfile which defaults to --crlfile and --proxy-capath which defaults to --capath. Curl now also supports %{proxy_ssl_verify_result} --write-out variable, similar to the existing %{ssl_verify_result} variable. Supported backends: OpenSSL, GnuTLS, and NSS. * A SOCKS proxy + HTTP/HTTPS proxy combination: If both --socks* and --proxy options are given, Curl first connects to the SOCKS proxy and then connects (through SOCKS) to the HTTP or HTTPS proxy. TODO: Update documentation for the new APIs and --proxy-* options. Look for "Added in 7.XXX" marks.
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service.length = serviceptr_length;
service.value = malloc(service.length);
if(!service.value)
return CURLE_OUT_OF_MEMORY;
memcpy(service.value, serviceptr, service.length);
gss_major_status = gss_import_name(&gss_minor_status, &service,
(gss_OID) GSS_C_NULL_OID, &server);
}
else {
proxy: Support HTTPS proxy and SOCKS+HTTP(s) * HTTPS proxies: An HTTPS proxy receives all transactions over an SSL/TLS connection. Once a secure connection with the proxy is established, the user agent uses the proxy as usual, including sending CONNECT requests to instruct the proxy to establish a [usually secure] TCP tunnel with an origin server. HTTPS proxies protect nearly all aspects of user-proxy communications as opposed to HTTP proxies that receive all requests (including CONNECT requests) in vulnerable clear text. With HTTPS proxies, it is possible to have two concurrent _nested_ SSL/TLS sessions: the "outer" one between the user agent and the proxy and the "inner" one between the user agent and the origin server (through the proxy). This change adds supports for such nested sessions as well. A secure connection with a proxy requires its own set of the usual SSL options (their actual descriptions differ and need polishing, see TODO): --proxy-cacert FILE CA certificate to verify peer against --proxy-capath DIR CA directory to verify peer against --proxy-cert CERT[:PASSWD] Client certificate file and password --proxy-cert-type TYPE Certificate file type (DER/PEM/ENG) --proxy-ciphers LIST SSL ciphers to use --proxy-crlfile FILE Get a CRL list in PEM format from the file --proxy-insecure Allow connections to proxies with bad certs --proxy-key KEY Private key file name --proxy-key-type TYPE Private key file type (DER/PEM/ENG) --proxy-pass PASS Pass phrase for the private key --proxy-ssl-allow-beast Allow security flaw to improve interop --proxy-sslv2 Use SSLv2 --proxy-sslv3 Use SSLv3 --proxy-tlsv1 Use TLSv1 --proxy-tlsuser USER TLS username --proxy-tlspassword STRING TLS password --proxy-tlsauthtype STRING TLS authentication type (default SRP) All --proxy-foo options are independent from their --foo counterparts, except --proxy-crlfile which defaults to --crlfile and --proxy-capath which defaults to --capath. Curl now also supports %{proxy_ssl_verify_result} --write-out variable, similar to the existing %{ssl_verify_result} variable. Supported backends: OpenSSL, GnuTLS, and NSS. * A SOCKS proxy + HTTP/HTTPS proxy combination: If both --socks* and --proxy options are given, Curl first connects to the SOCKS proxy and then connects (through SOCKS) to the HTTP or HTTPS proxy. TODO: Update documentation for the new APIs and --proxy-* options. Look for "Added in 7.XXX" marks.
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service.value = malloc(serviceptr_length +
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strlen(conn->socks_proxy.host.name) + 2);
if(!service.value)
return CURLE_OUT_OF_MEMORY;
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service.length = serviceptr_length +
strlen(conn->socks_proxy.host.name) + 1;
snprintf(service.value, service.length + 1, "%s@%s",
proxy: Support HTTPS proxy and SOCKS+HTTP(s) * HTTPS proxies: An HTTPS proxy receives all transactions over an SSL/TLS connection. Once a secure connection with the proxy is established, the user agent uses the proxy as usual, including sending CONNECT requests to instruct the proxy to establish a [usually secure] TCP tunnel with an origin server. HTTPS proxies protect nearly all aspects of user-proxy communications as opposed to HTTP proxies that receive all requests (including CONNECT requests) in vulnerable clear text. With HTTPS proxies, it is possible to have two concurrent _nested_ SSL/TLS sessions: the "outer" one between the user agent and the proxy and the "inner" one between the user agent and the origin server (through the proxy). This change adds supports for such nested sessions as well. A secure connection with a proxy requires its own set of the usual SSL options (their actual descriptions differ and need polishing, see TODO): --proxy-cacert FILE CA certificate to verify peer against --proxy-capath DIR CA directory to verify peer against --proxy-cert CERT[:PASSWD] Client certificate file and password --proxy-cert-type TYPE Certificate file type (DER/PEM/ENG) --proxy-ciphers LIST SSL ciphers to use --proxy-crlfile FILE Get a CRL list in PEM format from the file --proxy-insecure Allow connections to proxies with bad certs --proxy-key KEY Private key file name --proxy-key-type TYPE Private key file type (DER/PEM/ENG) --proxy-pass PASS Pass phrase for the private key --proxy-ssl-allow-beast Allow security flaw to improve interop --proxy-sslv2 Use SSLv2 --proxy-sslv3 Use SSLv3 --proxy-tlsv1 Use TLSv1 --proxy-tlsuser USER TLS username --proxy-tlspassword STRING TLS password --proxy-tlsauthtype STRING TLS authentication type (default SRP) All --proxy-foo options are independent from their --foo counterparts, except --proxy-crlfile which defaults to --crlfile and --proxy-capath which defaults to --capath. Curl now also supports %{proxy_ssl_verify_result} --write-out variable, similar to the existing %{ssl_verify_result} variable. Supported backends: OpenSSL, GnuTLS, and NSS. * A SOCKS proxy + HTTP/HTTPS proxy combination: If both --socks* and --proxy options are given, Curl first connects to the SOCKS proxy and then connects (through SOCKS) to the HTTP or HTTPS proxy. TODO: Update documentation for the new APIs and --proxy-* options. Look for "Added in 7.XXX" marks.
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serviceptr, conn->socks_proxy.host.name);
gss_major_status = gss_import_name(&gss_minor_status, &service,
GSS_C_NT_HOSTBASED_SERVICE, &server);
}
gss_release_buffer(&gss_status, &service); /* clear allocated memory */
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if(check_gss_err(data, gss_major_status,
gss_minor_status, "gss_import_name()")) {
failf(data, "Failed to create service name.");
gss_release_name(&gss_status, &server);
return CURLE_COULDNT_CONNECT;
}
/* As long as we need to keep sending some context info, and there's no */
/* errors, keep sending it... */
for(;;) {
gss_major_status = Curl_gss_init_sec_context(data,
&gss_minor_status,
&gss_context,
server,
&Curl_krb5_mech_oid,
NULL,
gss_token,
&gss_send_token,
TRUE,
&gss_ret_flags);
if(gss_token != GSS_C_NO_BUFFER)
gss_release_buffer(&gss_status, &gss_recv_token);
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if(check_gss_err(data, gss_major_status,
gss_minor_status, "gss_init_sec_context")) {
gss_release_name(&gss_status, &server);
gss_release_buffer(&gss_status, &gss_recv_token);
gss_release_buffer(&gss_status, &gss_send_token);
gss_delete_sec_context(&gss_status, &gss_context, NULL);
failf(data, "Failed to initial GSS-API token.");
return CURLE_COULDNT_CONNECT;
}
if(gss_send_token.length != 0) {
socksreq[0] = 1; /* GSS-API subnegotiation version */
socksreq[1] = 1; /* authentication message type */
us_length = htons((short)gss_send_token.length);
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memcpy(socksreq + 2, &us_length, sizeof(short));
code = Curl_write_plain(conn, sock, (char *)socksreq, 4, &written);
if(code || (4 != written)) {
failf(data, "Failed to send GSS-API authentication request.");
gss_release_name(&gss_status, &server);
gss_release_buffer(&gss_status, &gss_recv_token);
gss_release_buffer(&gss_status, &gss_send_token);
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_COULDNT_CONNECT;
}
code = Curl_write_plain(conn, sock, (char *)gss_send_token.value,
gss_send_token.length, &written);
if(code || ((ssize_t)gss_send_token.length != written)) {
failf(data, "Failed to send GSS-API authentication token.");
gss_release_name(&gss_status, &server);
gss_release_buffer(&gss_status, &gss_recv_token);
gss_release_buffer(&gss_status, &gss_send_token);
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_COULDNT_CONNECT;
}
}
gss_release_buffer(&gss_status, &gss_send_token);
gss_release_buffer(&gss_status, &gss_recv_token);
if(gss_major_status != GSS_S_CONTINUE_NEEDED) break;
/* analyse response */
/* GSS-API response looks like
* +----+------+-----+----------------+
* |VER | MTYP | LEN | TOKEN |
* +----+------+----------------------+
* | 1 | 1 | 2 | up to 2^16 - 1 |
* +----+------+-----+----------------+
*/
result = Curl_blockread_all(conn, sock, (char *)socksreq, 4, &actualread);
if(result || (actualread != 4)) {
failf(data, "Failed to receive GSS-API authentication response.");
gss_release_name(&gss_status, &server);
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_COULDNT_CONNECT;
}
/* ignore the first (VER) byte */
if(socksreq[1] == 255) { /* status / message type */
failf(data, "User was rejected by the SOCKS5 server (%d %d).",
socksreq[0], socksreq[1]);
gss_release_name(&gss_status, &server);
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_COULDNT_CONNECT;
}
if(socksreq[1] != 1) { /* status / messgae type */
failf(data, "Invalid GSS-API authentication response type (%d %d).",
socksreq[0], socksreq[1]);
gss_release_name(&gss_status, &server);
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_COULDNT_CONNECT;
}
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memcpy(&us_length, socksreq + 2, sizeof(short));
us_length = ntohs(us_length);
gss_recv_token.length = us_length;
gss_recv_token.value = malloc(us_length);
if(!gss_recv_token.value) {
failf(data,
"Could not allocate memory for GSS-API authentication "
"response token.");
gss_release_name(&gss_status, &server);
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_OUT_OF_MEMORY;
}
result = Curl_blockread_all(conn, sock, (char *)gss_recv_token.value,
gss_recv_token.length, &actualread);
if(result || (actualread != us_length)) {
failf(data, "Failed to receive GSS-API authentication token.");
gss_release_name(&gss_status, &server);
gss_release_buffer(&gss_status, &gss_recv_token);
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_COULDNT_CONNECT;
}
gss_token = &gss_recv_token;
}
gss_release_name(&gss_status, &server);
/* Everything is good so far, user was authenticated! */
gss_major_status = gss_inquire_context(&gss_minor_status, gss_context,
&gss_client_name, NULL, NULL, NULL,
NULL, NULL, NULL);
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if(check_gss_err(data, gss_major_status,
gss_minor_status, "gss_inquire_context")) {
gss_delete_sec_context(&gss_status, &gss_context, NULL);
gss_release_name(&gss_status, &gss_client_name);
failf(data, "Failed to determine user name.");
return CURLE_COULDNT_CONNECT;
}
gss_major_status = gss_display_name(&gss_minor_status, gss_client_name,
&gss_send_token, NULL);
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if(check_gss_err(data, gss_major_status,
gss_minor_status, "gss_display_name")) {
gss_delete_sec_context(&gss_status, &gss_context, NULL);
gss_release_name(&gss_status, &gss_client_name);
gss_release_buffer(&gss_status, &gss_send_token);
failf(data, "Failed to determine user name.");
return CURLE_COULDNT_CONNECT;
}
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user = malloc(gss_send_token.length + 1);
if(!user) {
gss_delete_sec_context(&gss_status, &gss_context, NULL);
gss_release_name(&gss_status, &gss_client_name);
gss_release_buffer(&gss_status, &gss_send_token);
return CURLE_OUT_OF_MEMORY;
}
memcpy(user, gss_send_token.value, gss_send_token.length);
user[gss_send_token.length] = '\0';
gss_release_name(&gss_status, &gss_client_name);
gss_release_buffer(&gss_status, &gss_send_token);
infof(data, "SOCKS5 server authencticated user %s with GSS-API.\n",user);
free(user);
user = NULL;
/* Do encryption */
socksreq[0] = 1; /* GSS-API subnegotiation version */
socksreq[1] = 2; /* encryption message type */
gss_enc = 0; /* no data protection */
/* do confidentiality protection if supported */
if(gss_ret_flags & GSS_C_CONF_FLAG)
gss_enc = 2;
/* else do integrity protection */
else if(gss_ret_flags & GSS_C_INTEG_FLAG)
gss_enc = 1;
infof(data, "SOCKS5 server supports GSS-API %s data protection.\n",
(gss_enc == 0)?"no":((gss_enc==1)?"integrity":"confidentiality"));
/* force for the moment to no data protection */
gss_enc = 0;
/*
* Sending the encryption type in clear seems wrong. It should be
* protected with gss_seal()/gss_wrap(). See RFC1961 extract below
* The NEC reference implementations on which this is based is
* therefore at fault
*
* +------+------+------+.......................+
* + ver | mtyp | len | token |
* +------+------+------+.......................+
* + 0x01 | 0x02 | 0x02 | up to 2^16 - 1 octets |
* +------+------+------+.......................+
*
* Where:
*
* - "ver" is the protocol version number, here 1 to represent the
* first version of the SOCKS/GSS-API protocol
*
* - "mtyp" is the message type, here 2 to represent a protection
* -level negotiation message
*
* - "len" is the length of the "token" field in octets
*
* - "token" is the GSS-API encapsulated protection level
*
* The token is produced by encapsulating an octet containing the
* required protection level using gss_seal()/gss_wrap() with conf_req
* set to FALSE. The token is verified using gss_unseal()/
* gss_unwrap().
*
*/
if(data->set.socks5_gssapi_nec) {
us_length = htons((short)1);
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memcpy(socksreq + 2, &us_length, sizeof(short));
}
else {
gss_send_token.length = 1;
gss_send_token.value = malloc(1);
if(!gss_send_token.value) {
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_OUT_OF_MEMORY;
}
memcpy(gss_send_token.value, &gss_enc, 1);
gss_major_status = gss_wrap(&gss_minor_status, gss_context, 0,
GSS_C_QOP_DEFAULT, &gss_send_token,
&gss_conf_state, &gss_w_token);
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if(check_gss_err(data, gss_major_status, gss_minor_status, "gss_wrap")) {
gss_release_buffer(&gss_status, &gss_send_token);
gss_release_buffer(&gss_status, &gss_w_token);
gss_delete_sec_context(&gss_status, &gss_context, NULL);
failf(data, "Failed to wrap GSS-API encryption value into token.");
return CURLE_COULDNT_CONNECT;
}
gss_release_buffer(&gss_status, &gss_send_token);
us_length = htons((short)gss_w_token.length);
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memcpy(socksreq + 2, &us_length, sizeof(short));
}
code = Curl_write_plain(conn, sock, (char *)socksreq, 4, &written);
if(code || (4 != written)) {
failf(data, "Failed to send GSS-API encryption request.");
gss_release_buffer(&gss_status, &gss_w_token);
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_COULDNT_CONNECT;
}
if(data->set.socks5_gssapi_nec) {
memcpy(socksreq, &gss_enc, 1);
code = Curl_write_plain(conn, sock, socksreq, 1, &written);
if(code || ( 1 != written)) {
failf(data, "Failed to send GSS-API encryption type.");
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_COULDNT_CONNECT;
}
}
else {
code = Curl_write_plain(conn, sock, (char *)gss_w_token.value,
gss_w_token.length, &written);
if(code || ((ssize_t)gss_w_token.length != written)) {
failf(data, "Failed to send GSS-API encryption type.");
gss_release_buffer(&gss_status, &gss_w_token);
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_COULDNT_CONNECT;
}
gss_release_buffer(&gss_status, &gss_w_token);
}
result = Curl_blockread_all(conn, sock, (char *)socksreq, 4, &actualread);
if(result || (actualread != 4)) {
failf(data, "Failed to receive GSS-API encryption response.");
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_COULDNT_CONNECT;
}
/* ignore the first (VER) byte */
if(socksreq[1] == 255) { /* status / message type */
failf(data, "User was rejected by the SOCKS5 server (%d %d).",
socksreq[0], socksreq[1]);
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_COULDNT_CONNECT;
}
if(socksreq[1] != 2) { /* status / messgae type */
failf(data, "Invalid GSS-API encryption response type (%d %d).",
socksreq[0], socksreq[1]);
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_COULDNT_CONNECT;
}
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memcpy(&us_length, socksreq + 2, sizeof(short));
us_length = ntohs(us_length);
gss_recv_token.length = us_length;
gss_recv_token.value = malloc(gss_recv_token.length);
if(!gss_recv_token.value) {
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_OUT_OF_MEMORY;
}
result = Curl_blockread_all(conn, sock, (char *)gss_recv_token.value,
gss_recv_token.length, &actualread);
if(result || (actualread != us_length)) {
failf(data, "Failed to receive GSS-API encryptrion type.");
gss_release_buffer(&gss_status, &gss_recv_token);
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_COULDNT_CONNECT;
}
if(!data->set.socks5_gssapi_nec) {
gss_major_status = gss_unwrap(&gss_minor_status, gss_context,
&gss_recv_token, &gss_w_token,
0, GSS_C_QOP_DEFAULT);
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if(check_gss_err(data, gss_major_status, gss_minor_status, "gss_unwrap")) {
gss_release_buffer(&gss_status, &gss_recv_token);
gss_release_buffer(&gss_status, &gss_w_token);
gss_delete_sec_context(&gss_status, &gss_context, NULL);
failf(data, "Failed to unwrap GSS-API encryption value into token.");
return CURLE_COULDNT_CONNECT;
}
gss_release_buffer(&gss_status, &gss_recv_token);
if(gss_w_token.length != 1) {
failf(data, "Invalid GSS-API encryption response length (%d).",
gss_w_token.length);
gss_release_buffer(&gss_status, &gss_w_token);
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_COULDNT_CONNECT;
}
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memcpy(socksreq, gss_w_token.value, gss_w_token.length);
gss_release_buffer(&gss_status, &gss_w_token);
}
else {
if(gss_recv_token.length != 1) {
failf(data, "Invalid GSS-API encryption response length (%d).",
gss_recv_token.length);
gss_release_buffer(&gss_status, &gss_recv_token);
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_COULDNT_CONNECT;
}
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memcpy(socksreq, gss_recv_token.value, gss_recv_token.length);
gss_release_buffer(&gss_status, &gss_recv_token);
}
infof(data, "SOCKS5 access with%s protection granted.\n",
(socksreq[0] == 0)?"out GSS-API data":
((socksreq[0] == 1)?" GSS-API integrity":" GSS-API confidentiality"));
conn->socks5_gssapi_enctype = socksreq[0];
if(socksreq[0] == 0)
gss_delete_sec_context(&gss_status, &gss_context, NULL);
return CURLE_OK;
}
#endif /* HAVE_GSSAPI && !CURL_DISABLE_PROXY */