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authorDaniel Stenberg <daniel@haxx.se>2009-01-28 21:33:58 +0000
committerDaniel Stenberg <daniel@haxx.se>2009-01-28 21:33:58 +0000
commitde4610a55f9e99bebaf448ca33e2e43baf977c74 (patch)
tree108574cc0c8a3593046f08e16cc898f29f77626c /lib/socks_gssapi.c
parent6e34c2d59a96b406a76d8922561a9d57c55e0dbc (diff)
downloadcurl-de4610a55f9e99bebaf448ca33e2e43baf977c74.tar.gz
- Markus Moeller introduced two new options to libcurl:
CURLOPT_SOCKS5_GSSAPI_SERVICE and CURLOPT_SOCKS5_GSSAPI_NEC to allow libcurl to do GSS-style authentication with SOCKS5 proxies. The curl tool got the options called --socks5-gssapi-service and --socks5-gssapi-nec to enable these.
Diffstat (limited to 'lib/socks_gssapi.c')
-rw-r--r--lib/socks_gssapi.c547
1 files changed, 547 insertions, 0 deletions
diff --git a/lib/socks_gssapi.c b/lib/socks_gssapi.c
new file mode 100644
index 000000000..cd9e1a4d3
--- /dev/null
+++ b/lib/socks_gssapi.c
@@ -0,0 +1,547 @@
+/***************************************************************************
+ * _ _ ____ _
+ * Project ___| | | | _ \| |
+ * / __| | | | |_) | |
+ * | (__| |_| | _ <| |___
+ * \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 2009, Markus Moeller, <markus_moeller@compuserve.com>
+ *
+ * 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 http://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.
+ *
+ * $Id$
+ ***************************************************************************/
+
+#include "setup.h"
+
+#ifdef HAVE_GSSAPI
+#ifdef HAVE_OLD_GSSMIT
+#define GSS_C_NT_HOSTBASED_SERVICE gss_nt_service_name
+#endif
+#ifndef gss_nt_service_name
+#define gss_nt_service_name GSS_C_NT_HOSTBASED_SERVICE
+#endif
+#include <string.h>
+
+#ifdef NEED_MALLOC_H
+#include <malloc.h>
+#endif
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+
+#include "urldata.h"
+#include "sendf.h"
+#include "connect.h"
+#include "timeval.h"
+#include "socks.h"
+
+static gss_ctx_id_t gss_context = GSS_C_NO_CONTEXT;
+
+#define _MPRINTF_REPLACE /* use our functions only */
+#include <curl/mprintf.h>
+
+/* The last #include file should be: */
+#include "memdebug.h"
+
+/*
+ * Helper gssapi error functions.
+ */
+static int check_gss_err(struct SessionHandle *data,
+ OM_uint32 major_status,
+ OM_uint32 minor_status,
+ const char* function)
+{
+ if(GSS_ERROR(major_status)) {
+ 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) {
+ 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) {
+ 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) {
+ 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);
+ }
+ failf(data, "GSSAPI error: %s failed:\n%s\n", function, buf);
+ return(1);
+ }
+
+ return(0);
+}
+
+CURLcode Curl_SOCKS5_gssapi_negotiate(int sockindex,
+ struct connectdata *conn)
+{
+ struct SessionHandle *data = conn->data;
+ curl_socket_t sock = conn->sock[sockindex];
+ CURLcode code;
+ ssize_t actualread;
+ ssize_t written;
+ int result;
+ long timeout;
+ 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;
+ u_short us_length;
+ char *user=NULL;
+ unsigned char socksreq[4]; /* room for gssapi exchange header only */
+ char *serviceptr = data->set.str[STRING_SOCKS5_GSSAPI_SERVICE];
+
+ /* get timeout */
+ timeout = Curl_timeleft(conn, NULL, TRUE);
+
+ /* GSSAPI request looks like
+ * +----+------+-----+----------------+
+ * |VER | MTYP | LEN | TOKEN |
+ * +----+------+----------------------+
+ * | 1 | 1 | 2 | up to 2^16 - 1 |
+ * +----+------+-----+----------------+
+ */
+
+ /* prepare service name */
+ if (strchr(serviceptr,'/')) {
+ service.value = malloc(strlen(serviceptr));
+ if(!service.value)
+ return CURLE_OUT_OF_MEMORY;
+ service.length = strlen(serviceptr);
+ memcpy(service.value, serviceptr, service.length);
+
+ gss_major_status = gss_import_name(&gss_minor_status, &service,
+ (gss_OID) GSS_C_NULL_OID, &server);
+ }
+ else {
+ service.value = malloc(strlen(serviceptr) +strlen(conn->proxy.name)+2);
+ if(!service.value)
+ return CURLE_OUT_OF_MEMORY;
+ service.length = strlen(serviceptr) +strlen(conn->proxy.name)+1;
+ snprintf(service.value, service.length+1, "%s@%s",
+ serviceptr, conn->proxy.name);
+
+ gss_major_status = gss_import_name(&gss_minor_status, &service,
+ gss_nt_service_name, &server);
+ }
+
+ gss_release_buffer(&gss_status, &service); /* clear allocated memory */
+
+ 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 = gss_init_sec_context(&gss_minor_status,
+ GSS_C_NO_CREDENTIAL,
+ &gss_context, server,
+ GSS_C_NULL_OID,
+ GSS_C_MUTUAL_FLAG |
+ GSS_C_REPLAY_FLAG,
+ 0,
+ NULL,
+ gss_token,
+ NULL,
+ &gss_send_token,
+ &gss_ret_flags,
+ NULL);
+
+ if(gss_token != GSS_C_NO_BUFFER)
+ gss_release_buffer(&gss_status, &gss_recv_token);
+ 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 GSSAPI token.");
+ return CURLE_COULDNT_CONNECT;
+ }
+
+ if(gss_send_token.length != 0) {
+ socksreq[0] = 1; /* gssapi subnegotiation version */
+ socksreq[1] = 1; /* authentication message type */
+ us_length = htons((short)gss_send_token.length);
+ memcpy(socksreq+2,&us_length,sizeof(short));
+
+ code = Curl_write_plain(conn, sock, (char *)socksreq, 4, &written);
+ if((code != CURLE_OK) || (4 != written)) {
+ failf(data, "Failed to send GSSAPI 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 != CURLE_OK) || ((ssize_t)gss_send_token.length != written)) {
+ failf(data, "Failed to send GSSAPI 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 */
+
+ /* GSSAPI 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, timeout);
+ if(result != CURLE_OK || actualread != 4) {
+ failf(data, "Failed to receive GSSAPI 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 GSSAPI 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;
+ }
+
+ 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 GSSAPI 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, timeout);
+
+ if(result != CURLE_OK || actualread != us_length) {
+ failf(data, "Failed to receive GSSAPI 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);
+ 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);
+ 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;
+ }
+ 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 gssapi.\n",user);
+ free(user);
+ user=NULL;
+
+ /* Do encryption */
+ socksreq[0] = 1; /* gssapi 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 gssapi %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);
+ 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);
+
+ 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 GSSAPI encryption value into token.");
+ return CURLE_COULDNT_CONNECT;
+ }
+ gss_release_buffer(&gss_status, &gss_send_token);
+
+ us_length = htons((short)gss_w_token.length);
+ memcpy(socksreq+2,&us_length,sizeof(short));
+ }
+
+ code = Curl_write_plain(conn, sock, (char *)socksreq, 4, &written);
+ if((code != CURLE_OK) || (4 != written)) {
+ failf(data, "Failed to send GSSAPI 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 != CURLE_OK) || ( 1 != written)) {
+ failf(data, "Failed to send GSSAPI 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 != CURLE_OK) || ((ssize_t)gss_w_token.length != written)) {
+ failf(data, "Failed to send GSSAPI 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, timeout);
+ if(result != CURLE_OK || actualread != 4) {
+ failf(data, "Failed to receive GSSAPI 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 GSSAPI encryption response type (%d %d).",
+ socksreq[0], socksreq[1]);
+ gss_delete_sec_context(&gss_status, &gss_context, NULL);
+ return CURLE_COULDNT_CONNECT;
+ }
+
+ 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, timeout);
+
+ if(result != CURLE_OK || actualread != us_length) {
+ failf(data, "Failed to receive GSSAPI 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);
+
+ 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 GSSAPI 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 GSSAPI 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;
+ }
+
+ 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 GSSAPI 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;
+ }
+
+ 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 gssapi data":
+ ((socksreq[0]==1)?" gssapi integrity":" gssapi confidentiality"));
+
+ conn->socks5_gssapi_enctype = socksreq[0];
+ if(socksreq[0] == 0)
+ gss_delete_sec_context(&gss_status, &gss_context, NULL);
+
+ return CURLE_OK;
+}
+#endif