curl/lib/curl_ntlm_wb.c

392 lines
11 KiB
C

/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 1998 - 2012, 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 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.
*
***************************************************************************/
#include "curl_setup.h"
#if defined(USE_NTLM) && defined(NTLM_WB_ENABLED)
/*
* NTLM details:
*
* http://davenport.sourceforge.net/ntlm.html
* http://www.innovation.ch/java/ntlm.html
*/
#define DEBUG_ME 0
#ifdef HAVE_SYS_WAIT_H
#include <sys/wait.h>
#endif
#ifdef HAVE_SIGNAL_H
#include <signal.h>
#endif
#include "urldata.h"
#include "sendf.h"
#include "select.h"
#include "curl_ntlm_wb.h"
#include "url.h"
#include "strerror.h"
#include "curl_memory.h"
#define _MPRINTF_REPLACE /* use our functions only */
#include <curl/mprintf.h>
/* The last #include file should be: */
#include "memdebug.h"
#if DEBUG_ME
# define DEBUG_OUT(x) x
#else
# define DEBUG_OUT(x) Curl_nop_stmt
#endif
/* Portable 'sclose_nolog' used only in child process instead of 'sclose'
to avoid fooling the socket leak detector */
#if defined(HAVE_CLOSESOCKET)
# define sclose_nolog(x) closesocket((x))
#elif defined(HAVE_CLOSESOCKET_CAMEL)
# define sclose_nolog(x) CloseSocket((x))
#else
# define sclose_nolog(x) close((x))
#endif
void Curl_ntlm_wb_cleanup(struct connectdata *conn)
{
if(conn->ntlm_auth_hlpr_socket != CURL_SOCKET_BAD) {
sclose(conn->ntlm_auth_hlpr_socket);
conn->ntlm_auth_hlpr_socket = CURL_SOCKET_BAD;
}
if(conn->ntlm_auth_hlpr_pid) {
int i;
for(i = 0; i < 4; i++) {
pid_t ret = waitpid(conn->ntlm_auth_hlpr_pid, NULL, WNOHANG);
if(ret == conn->ntlm_auth_hlpr_pid || errno == ECHILD)
break;
switch(i) {
case 0:
kill(conn->ntlm_auth_hlpr_pid, SIGTERM);
break;
case 1:
/* Give the process another moment to shut down cleanly before
bringing down the axe */
Curl_wait_ms(1);
break;
case 2:
kill(conn->ntlm_auth_hlpr_pid, SIGKILL);
break;
case 3:
break;
}
}
conn->ntlm_auth_hlpr_pid = 0;
}
Curl_safefree(conn->challenge_header);
conn->challenge_header = NULL;
Curl_safefree(conn->response_header);
conn->response_header = NULL;
}
static CURLcode ntlm_wb_init(struct connectdata *conn, const char *userp)
{
curl_socket_t sockfds[2];
pid_t child_pid;
const char *username;
char *slash, *domain = NULL;
const char *ntlm_auth = NULL;
char *ntlm_auth_alloc = NULL;
int error;
/* Return if communication with ntlm_auth already set up */
if(conn->ntlm_auth_hlpr_socket != CURL_SOCKET_BAD ||
conn->ntlm_auth_hlpr_pid)
return CURLE_OK;
username = userp;
slash = strpbrk(username, "\\/");
if(slash) {
if((domain = strdup(username)) == NULL)
return CURLE_OUT_OF_MEMORY;
slash = domain + (slash - username);
*slash = '\0';
username = username + (slash - domain) + 1;
}
/* For testing purposes, when DEBUGBUILD is defined and environment
variable CURL_NTLM_WB_FILE is set a fake_ntlm is used to perform
NTLM challenge/response which only accepts commands and output
strings pre-written in test case definitions */
#ifdef DEBUGBUILD
ntlm_auth_alloc = curl_getenv("CURL_NTLM_WB_FILE");
if(ntlm_auth_alloc)
ntlm_auth = ntlm_auth_alloc;
else
#endif
ntlm_auth = NTLM_WB_FILE;
if(access(ntlm_auth, X_OK) != 0) {
error = ERRNO;
failf(conn->data, "Could not access ntlm_auth: %s errno %d: %s",
ntlm_auth, error, Curl_strerror(conn, error));
goto done;
}
if(socketpair(AF_UNIX, SOCK_STREAM, 0, sockfds)) {
error = ERRNO;
failf(conn->data, "Could not open socket pair. errno %d: %s",
error, Curl_strerror(conn, error));
goto done;
}
child_pid = fork();
if(child_pid == -1) {
error = ERRNO;
sclose(sockfds[0]);
sclose(sockfds[1]);
failf(conn->data, "Could not fork. errno %d: %s",
error, Curl_strerror(conn, error));
goto done;
}
else if(!child_pid) {
/*
* child process
*/
/* Don't use sclose in the child since it fools the socket leak detector */
sclose_nolog(sockfds[0]);
if(dup2(sockfds[1], STDIN_FILENO) == -1) {
error = ERRNO;
failf(conn->data, "Could not redirect child stdin. errno %d: %s",
error, Curl_strerror(conn, error));
exit(1);
}
if(dup2(sockfds[1], STDOUT_FILENO) == -1) {
error = ERRNO;
failf(conn->data, "Could not redirect child stdout. errno %d: %s",
error, Curl_strerror(conn, error));
exit(1);
}
if(domain)
execl(ntlm_auth, ntlm_auth,
"--helper-protocol", "ntlmssp-client-1",
"--use-cached-creds",
"--username", username,
"--domain", domain,
NULL);
else
execl(ntlm_auth, ntlm_auth,
"--helper-protocol", "ntlmssp-client-1",
"--use-cached-creds",
"--username", username,
NULL);
error = ERRNO;
sclose_nolog(sockfds[1]);
failf(conn->data, "Could not execl(). errno %d: %s",
error, Curl_strerror(conn, error));
exit(1);
}
sclose(sockfds[1]);
conn->ntlm_auth_hlpr_socket = sockfds[0];
conn->ntlm_auth_hlpr_pid = child_pid;
Curl_safefree(domain);
Curl_safefree(ntlm_auth_alloc);
return CURLE_OK;
done:
Curl_safefree(domain);
Curl_safefree(ntlm_auth_alloc);
return CURLE_REMOTE_ACCESS_DENIED;
}
static CURLcode ntlm_wb_response(struct connectdata *conn,
const char *input, curlntlm state)
{
ssize_t size;
char buf[200]; /* enough, type 1, 3 message length is less then 200 */
char *tmpbuf = buf;
size_t len_in = strlen(input), len_out = sizeof(buf);
while(len_in > 0) {
ssize_t written = swrite(conn->ntlm_auth_hlpr_socket, input, len_in);
if(written == -1) {
/* Interrupted by a signal, retry it */
if(errno == EINTR)
continue;
/* write failed if other errors happen */
goto done;
}
input += written;
len_in -= written;
}
/* Read one line */
while(len_out > 0) {
size = sread(conn->ntlm_auth_hlpr_socket, tmpbuf, len_out);
if(size == -1) {
if(errno == EINTR)
continue;
goto done;
}
else if(size == 0)
goto done;
else if(tmpbuf[size - 1] == '\n') {
tmpbuf[size - 1] = '\0';
goto wrfinish;
}
tmpbuf += size;
len_out -= size;
}
goto done;
wrfinish:
/* Samba/winbind installed but not configured */
if(state == NTLMSTATE_TYPE1 &&
size == 3 &&
buf[0] == 'P' && buf[1] == 'W')
return CURLE_REMOTE_ACCESS_DENIED;
/* invalid response */
if(size < 4)
goto done;
if(state == NTLMSTATE_TYPE1 &&
(buf[0]!='Y' || buf[1]!='R' || buf[2]!=' '))
goto done;
if(state == NTLMSTATE_TYPE2 &&
(buf[0]!='K' || buf[1]!='K' || buf[2]!=' ') &&
(buf[0]!='A' || buf[1]!='F' || buf[2]!=' '))
goto done;
conn->response_header = aprintf("NTLM %.*s", size - 4, buf + 3);
return CURLE_OK;
done:
return CURLE_REMOTE_ACCESS_DENIED;
}
/*
* This is for creating ntlm header output by delegating challenge/response
* to Samba's winbind daemon helper ntlm_auth.
*/
CURLcode Curl_output_ntlm_wb(struct connectdata *conn,
bool proxy)
{
/* point to the address of the pointer that holds the string to send to the
server, which is for a plain host or for a HTTP proxy */
char **allocuserpwd;
/* point to the name and password for this */
const char *userp;
/* point to the correct struct with this */
struct ntlmdata *ntlm;
struct auth *authp;
CURLcode res = CURLE_OK;
char *input;
DEBUGASSERT(conn);
DEBUGASSERT(conn->data);
if(proxy) {
allocuserpwd = &conn->allocptr.proxyuserpwd;
userp = conn->proxyuser;
ntlm = &conn->proxyntlm;
authp = &conn->data->state.authproxy;
}
else {
allocuserpwd = &conn->allocptr.userpwd;
userp = conn->user;
ntlm = &conn->ntlm;
authp = &conn->data->state.authhost;
}
authp->done = FALSE;
/* not set means empty */
if(!userp)
userp="";
switch(ntlm->state) {
case NTLMSTATE_TYPE1:
default:
/* Use Samba's 'winbind' daemon to support NTLM authentication,
* by delegating the NTLM challenge/response protocal to a helper
* in ntlm_auth.
* http://devel.squid-cache.org/ntlm/squid_helper_protocol.html
* http://www.samba.org/samba/docs/man/manpages-3/winbindd.8.html
* http://www.samba.org/samba/docs/man/manpages-3/ntlm_auth.1.html
* Preprocessor symbol 'NTLM_WB_ENABLED' is defined when this
* feature is enabled and 'NTLM_WB_FILE' symbol holds absolute
* filename of ntlm_auth helper.
* If NTLM authentication using winbind fails, go back to original
* request handling process.
*/
/* Create communication with ntlm_auth */
res = ntlm_wb_init(conn, userp);
if(res)
return res;
res = ntlm_wb_response(conn, "YR\n", ntlm->state);
if(res)
return res;
Curl_safefree(*allocuserpwd);
*allocuserpwd = aprintf("%sAuthorization: %s\r\n",
proxy ? "Proxy-" : "",
conn->response_header);
DEBUG_OUT(fprintf(stderr, "**** Header %s\n ", *allocuserpwd));
Curl_safefree(conn->response_header);
conn->response_header = NULL;
break;
case NTLMSTATE_TYPE2:
input = aprintf("TT %s\n", conn->challenge_header);
if(!input)
return CURLE_OUT_OF_MEMORY;
res = ntlm_wb_response(conn, input, ntlm->state);
free(input);
input = NULL;
if(res)
return res;
Curl_safefree(*allocuserpwd);
*allocuserpwd = aprintf("%sAuthorization: %s\r\n",
proxy ? "Proxy-" : "",
conn->response_header);
DEBUG_OUT(fprintf(stderr, "**** %s\n ", *allocuserpwd));
ntlm->state = NTLMSTATE_TYPE3; /* we sent a type-3 */
authp->done = TRUE;
Curl_ntlm_wb_cleanup(conn);
break;
case NTLMSTATE_TYPE3:
/* connection is already authenticated,
* don't send a header in future requests */
if(*allocuserpwd) {
free(*allocuserpwd);
*allocuserpwd=NULL;
}
authp->done = TRUE;
break;
}
return CURLE_OK;
}
#endif /* USE_NTLM && NTLM_WB_ENABLED */