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mirror of https://github.com/moparisthebest/curl synced 2024-12-21 15:48:49 -05:00

Remove all traces of FBOpenSSL SPNEGO support

This is just fundamentally broken. SPNEGO (RFC4178) is a protocol which
allows client and server to negotiate the underlying mechanism which will
actually be used to authenticate. This is *often* Kerberos, and can also
be NTLM and other things. And to complicate matters, there are various
different OIDs which can be used to specify the Kerberos mechanism too.

A SPNEGO exchange will identify *which* GSSAPI mechanism is being used,
and will exchange GSSAPI tokens which are appropriate for that mechanism.

But this SPNEGO implementation just strips the incoming SPNEGO packet
and extracts the token, if any. And completely discards the information
about *which* mechanism is being used. Then we *assume* it was Kerberos,
and feed the token into gss_init_sec_context() with the default
mechanism (GSS_S_NO_OID for the mech_type argument).

Furthermore... broken as this code is, it was never even *used* for input
tokens anyway, because higher layers of curl would just bail out if the
server actually said anything *back* to us in the negotiation. We assume
that we send a single token to the server, and it accepts it. If the server
wants to continue the exchange (as is required for NTLM and for SPNEGO
to do anything useful), then curl was broken anyway.

So the only bit which actually did anything was the bit in
Curl_output_negotiate(), which always generates an *initial* SPNEGO
token saying "Hey, I support only the Kerberos mechanism and this is its
token".

You could have done that by manually just prefixing the Kerberos token
with the appropriate bytes, if you weren't going to do any proper SPNEGO
handling. There's no need for the FBOpenSSL library at all.

The sane way to do SPNEGO is just to *ask* the GSSAPI library to do
SPNEGO. That's what the 'mech_type' argument to gss_init_sec_context()
is for. And then it should all Just Work™.

That 'sane way' will be added in a subsequent patch, as will bug fixes
for our failure to handle any exchange other than a single outbound
token to the server which results in immediate success.
This commit is contained in:
David Woodhouse 2014-07-11 09:37:18 +01:00 committed by Daniel Stenberg
parent 223612afa2
commit 9ad282b1ae
21 changed files with 11 additions and 247 deletions

View File

@ -151,7 +151,6 @@ dnl initialize all the info variables
curl_ssh_msg="no (--with-libssh2)"
curl_zlib_msg="no (--with-zlib)"
curl_gss_msg="no (--with-gssapi)"
curl_spnego_msg="no (--with-spnego)"
curl_tls_srp_msg="no (--enable-tls-srp)"
curl_res_msg="default (--enable-ares / --enable-threaded-resolver)"
curl_ipv6_msg="no (--enable-ipv6)"
@ -1134,41 +1133,6 @@ no)
;;
esac
dnl **********************************************************************
dnl Check for FBopenssl(SPNEGO) libraries
dnl **********************************************************************
AC_ARG_WITH(spnego,
AC_HELP_STRING([--with-spnego=DIR],
[Specify location of SPNEGO library fbopenssl]), [
SPNEGO_ROOT="$withval"
if test x"$SPNEGO_ROOT" != xno; then
want_spnego="yes"
fi
])
AC_MSG_CHECKING([if SPNEGO support is requested])
if test x"$want_spnego" = xyes; then
if test X"$SPNEGO_ROOT" = Xyes; then
AC_MSG_ERROR([FBOpenSSL libs and/or directories were not found where specified!])
AC_MSG_RESULT(no)
else
if test -z "$SPNEGO_LIB_DIR"; then
LDFLAGS="$LDFLAGS -L$SPNEGO_ROOT -lfbopenssl"
else
LDFLAGS="$LDFLAGS $SPNEGO_LIB_DIR"
fi
AC_MSG_RESULT(yes)
AC_DEFINE(HAVE_SPNEGO, 1,
[Define this if you have the SPNEGO library fbopenssl])
curl_spnego_msg="enabled"
fi
else
AC_MSG_RESULT(no)
fi
dnl **********************************************************************
dnl Check for GSS-API libraries
dnl **********************************************************************
@ -3406,9 +3370,6 @@ fi
if test "x$USE_NGHTTP2" = "x1"; then
SUPPORT_FEATURES="$SUPPORT_FEATURES HTTP2"
fi
if test "x$curl_spnego_msg" = "xenabled"; then
SUPPORT_FEATURES="$SUPPORT_FEATURES SPNEGO"
fi
if test "x$want_gss" = "xyes"; then
SUPPORT_FEATURES="$SUPPORT_FEATURES GSS-API"
fi
@ -3560,7 +3521,6 @@ AC_MSG_NOTICE([Configured to build curl/libcurl:
SSH support: ${curl_ssh_msg}
zlib support: ${curl_zlib_msg}
GSS-API support: ${curl_gss_msg}
SPNEGO support: ${curl_spnego_msg}
TLS-SRP support: ${curl_tls_srp_msg}
resolver: ${curl_res_msg}
ipv6 support: ${curl_ipv6_msg}

View File

@ -94,12 +94,6 @@ GNU GSS http://www.gnu.org/software/gss/
may not distribute binary curl packages that uses this if you build
curl to also link and use any Original BSD licensed libraries!
fbopenssl
(Used for SPNEGO support) Unclear license. Based on its name, I assume
that it uses the OpenSSL license and thus shares the same issues as
described for OpenSSL above.
libidn http://josefsson.org/libidn/
(Used for IDNA support) Uses the GNU Lesser General Public

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@ -148,9 +148,6 @@ endif
ifeq ($(findstring -sspi,$(CFG)),-sspi)
SSPI = 1
endif
ifeq ($(findstring -spnego,$(CFG)),-spnego)
SPNEGO = 1
endif
ifeq ($(findstring -ldaps,$(CFG)),-ldaps)
LDAPS = 1
endif
@ -230,9 +227,6 @@ ifdef SSPI
CFLAGS += -DUSE_SCHANNEL
endif
endif
ifdef SPNEGO
CFLAGS += -DHAVE_SPNEGO
endif
ifdef IPV6
CFLAGS += -DENABLE_IPV6 -D_WIN32_WINNT=0x0501
endif

View File

@ -211,9 +211,6 @@ endif
ifeq ($(findstring -idn,$(CFG)),-idn)
WITH_IDN = 1
endif
ifeq ($(findstring -spnego,$(CFG)),-spnego)
WITH_SPNEGO = 1
endif
ifeq ($(findstring -ipv6,$(CFG)),-ipv6)
ENABLE_IPV6 = 1
endif
@ -247,10 +244,6 @@ ifdef WITH_SSL
LDLIBS += $(OPENSSL_PATH)/out_nw_$(LIBARCH_L)/ssl.$(LIBEXT)
LDLIBS += $(OPENSSL_PATH)/out_nw_$(LIBARCH_L)/crypto.$(LIBEXT)
IMPORTS += GetProcessSwitchCount RunningProcess
ifdef WITH_SPNEGO
# INCLUDES += -I$(FBOPENSSL_PATH)/include
LDLIBS += $(FBOPENSSL_PATH)/nw/fbopenssl.$(LIBEXT)
endif
else
ifdef WITH_AXTLS
INCLUDES += -I$(AXTLS_PATH)/inc

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@ -1,7 +1,7 @@
#!/bin/sh
# install - install a program, script, or datafile
scriptversion=2011-01-19.21; # UTC
scriptversion=2011-11-20.07; # UTC
# This originates from X11R5 (mit/util/scripts/install.sh), which was
# later released in X11R6 (xc/config/util/install.sh) with the
@ -35,7 +35,7 @@ scriptversion=2011-01-19.21; # UTC
# FSF changes to this file are in the public domain.
#
# Calling this script install-sh is preferred over install.sh, to prevent
# `make' implicit rules from creating a file called install from it
# 'make' implicit rules from creating a file called install from it
# when there is no Makefile.
#
# This script is compatible with the BSD install script, but was written
@ -156,7 +156,7 @@ while test $# -ne 0; do
-s) stripcmd=$stripprog;;
-t) dst_arg=$2
# Protect names problematic for `test' and other utilities.
# Protect names problematic for 'test' and other utilities.
case $dst_arg in
-* | [=\(\)!]) dst_arg=./$dst_arg;;
esac
@ -190,7 +190,7 @@ if test $# -ne 0 && test -z "$dir_arg$dst_arg"; then
fi
shift # arg
dst_arg=$arg
# Protect names problematic for `test' and other utilities.
# Protect names problematic for 'test' and other utilities.
case $dst_arg in
-* | [=\(\)!]) dst_arg=./$dst_arg;;
esac
@ -202,7 +202,7 @@ if test $# -eq 0; then
echo "$0: no input file specified." >&2
exit 1
fi
# It's OK to call `install-sh -d' without argument.
# It's OK to call 'install-sh -d' without argument.
# This can happen when creating conditional directories.
exit 0
fi
@ -240,7 +240,7 @@ fi
for src
do
# Protect names problematic for `test' and other utilities.
# Protect names problematic for 'test' and other utilities.
case $src in
-* | [=\(\)!]) src=./$src;;
esac
@ -354,7 +354,7 @@ do
if test -z "$dir_arg" || {
# Check for POSIX incompatibilities with -m.
# HP-UX 11.23 and IRIX 6.5 mkdir -m -p sets group- or
# other-writeable bit of parent directory when it shouldn't.
# other-writable bit of parent directory when it shouldn't.
# FreeBSD 6.1 mkdir -m -p sets mode of existing directory.
ls_ld_tmpdir=`ls -ld "$tmpdir"`
case $ls_ld_tmpdir in

View File

@ -60,7 +60,7 @@ SYS_INCL = -I"$(%watcom)/h/nt" -I"$(%watcom)/h"
CFLAGS = -3r -mf -hc -zff -zgf -zq -zm -zc -s -fr=con -w2 -fpi -oilrtfm &
-wcd=201 -bt=nt -d+ -dWIN32 -dCURL_WANTS_CA_BUNDLE_ENV &
-dBUILDING_LIBCURL -dHAVE_SPNEGO=1 -I. -I"../include" $(SYS_INCL)
-dBUILDING_LIBCURL -I. -I"../include" $(SYS_INCL)
!ifdef %debug
DEBUG = -dDEBUG=1 -dDEBUGBUILD
@ -248,4 +248,4 @@ $(RESOURCE): libcurl.rc
.c{$(OBJ_STAT)}.obj:
$(CC) $(CFLAGS) -DCURL_STATICLIB $[@ -fo=$^@

View File

@ -137,9 +137,6 @@ endif
ifeq ($(findstring -sspi,$(CFG)),-sspi)
SSPI = 1
endif
ifeq ($(findstring -spnego,$(CFG)),-spnego)
SPNEGO = 1
endif
ifeq ($(findstring -ldaps,$(CFG)),-ldaps)
LDAPS = 1
endif

View File

@ -217,9 +217,6 @@ endif
ifeq ($(findstring -idn,$(CFG)),-idn)
WITH_IDN = 1
endif
ifeq ($(findstring -spnego,$(CFG)),-spnego)
WITH_SPNEGO = 1
endif
ifeq ($(findstring -ipv6,$(CFG)),-ipv6)
ENABLE_IPV6 = 1
endif
@ -247,10 +244,6 @@ ifdef WITH_SSL
LDLIBS += $(OPENSSL_PATH)/out_nw_$(LIBARCH_L)/crypto.$(LIBEXT)
IMPORTS += GetProcessSwitchCount RunningProcess
INSTDEP += ca-bundle.crt
ifdef WITH_SPNEGO
INCLUDES += -I$(FBOPENSSL_PATH)/include
LDLIBS += $(FBOPENSSL_PATH)/nw/fbopenssl.$(LIBEXT)
endif
else
ifdef WITH_AXTLS
INCLUDES += -I$(AXTLS_PATH)/inc

View File

@ -69,7 +69,6 @@
#define HAVE_SETMODE 1
#define HAVE_SIGNAL 1
#define HAVE_SOCKET 1
#define HAVE_SPNEGO 1
#define HAVE_STRDUP 1
#define HAVE_STRICMP 1
#define HAVE_STRTOLL 1

View File

@ -480,9 +480,6 @@
/* Define to 1 if you have the `socket' function. */
#define HAVE_SOCKET 1
/* Define this if you have the SPNEGO library fbopenssl */
/* #undef HAVE_SPNEGO */
/* Define to 1 if you have the `SSL_get_shutdown' function. */
/*#define HAVE_SSL_GET_SHUTDOWN 1*/

View File

@ -436,9 +436,6 @@
/* Define to 1 if you have the `socket' function. */
#define HAVE_SOCKET 1
/* Define this if you have the SPNEGO library fbopenssl */
/* #undef HAVE_SPNEGO */
/* Define to 1 if you have the <ssl.h> header file. */
/* #undef HAVE_SSL_H */
#define HAVE_SSL_H 1

View File

@ -547,9 +547,6 @@
/* Define to 1 if you have the `socket' function. */
#define HAVE_SOCKET 1
/* Define this if you have the SPNEGO library fbopenssl */
/* #undef HAVE_SPNEGO */
/* Define to 1 if you have the `SSL_get_shutdown' function. */
#define HAVE_SSL_GET_SHUTDOWN 1

View File

@ -528,9 +528,6 @@
/* Define to 1 if you have the `socket' function. */
#cmakedefine HAVE_SOCKET ${HAVE_SOCKET}
/* Define this if you have the SPNEGO library fbopenssl */
#cmakedefine HAVE_SPNEGO ${HAVE_SPNEGO}
/* Define to 1 if you have the `SSL_get_shutdown' function. */
#cmakedefine HAVE_SSL_GET_SHUTDOWN ${HAVE_SSL_GET_SHUTDOWN}

View File

@ -39,19 +39,6 @@
#include "curl_memory.h"
#include "url.h"
#ifdef HAVE_SPNEGO
# include <spnegohelp.h>
# ifdef USE_SSLEAY
# ifdef USE_OPENSSL
# include <openssl/objects.h>
# else
# include <objects.h>
# endif
# else
# error "Can't compile SPNEGO support without OpenSSL."
# endif
#endif
#define _MPRINTF_REPLACE /* use our functions only */
#include <curl/mprintf.h>
@ -191,53 +178,6 @@ int Curl_input_negotiate(struct connectdata *conn, bool proxy,
input_token.length = rawlen;
DEBUGASSERT(input_token.value != NULL);
#ifdef HAVE_SPNEGO /* Handle SPNEGO */
if(checkprefix("Negotiate", header)) {
unsigned char *spnegoToken = NULL;
size_t spnegoTokenLength = 0;
gss_buffer_desc mechToken = GSS_C_EMPTY_BUFFER;
spnegoToken = malloc(input_token.length);
if(spnegoToken == NULL) {
Curl_safefree(input_token.value);
return CURLE_OUT_OF_MEMORY;
}
memcpy(spnegoToken, input_token.value, input_token.length);
spnegoTokenLength = input_token.length;
if(!parseSpnegoTargetToken(spnegoToken,
spnegoTokenLength,
NULL,
NULL,
(unsigned char**)&mechToken.value,
&mechToken.length,
NULL,
NULL)) {
Curl_safefree(spnegoToken);
infof(data, "Parse SPNEGO Target Token failed\n");
}
else if(!mechToken.value || !mechToken.length) {
Curl_safefree(spnegoToken);
if(mechToken.value)
gss_release_buffer(&discard_st, &mechToken);
infof(data, "Parse SPNEGO Target Token succeeded (NULL token)\n");
}
else {
Curl_safefree(spnegoToken);
Curl_safefree(input_token.value);
input_token.value = malloc(mechToken.length);
if(input_token.value == NULL) {
gss_release_buffer(&discard_st, &mechToken);
return CURLE_OUT_OF_MEMORY;
}
memcpy(input_token.value, mechToken.value, mechToken.length);
input_token.length = mechToken.length;
gss_release_buffer(&discard_st, &mechToken);
infof(data, "Parse SPNEGO Target Token succeeded\n");
}
}
#endif
}
major_status = Curl_gss_init_sec_context(data,
@ -279,52 +219,6 @@ CURLcode Curl_output_negotiate(struct connectdata *conn, bool proxy)
CURLcode error;
OM_uint32 discard_st;
#ifdef HAVE_SPNEGO /* Handle SPNEGO */
if(checkprefix("Negotiate", neg_ctx->protocol)) {
ASN1_OBJECT *object = NULL;
unsigned char *responseToken = NULL;
size_t responseTokenLength = 0;
gss_buffer_desc spnegoToken = GSS_C_EMPTY_BUFFER;
responseToken = malloc(neg_ctx->output_token.length);
if(responseToken == NULL)
return CURLE_OUT_OF_MEMORY;
memcpy(responseToken, neg_ctx->output_token.value,
neg_ctx->output_token.length);
responseTokenLength = neg_ctx->output_token.length;
object = OBJ_txt2obj("1.2.840.113554.1.2.2", 1);
if(!object) {
Curl_safefree(responseToken);
return CURLE_OUT_OF_MEMORY;
}
if(!makeSpnegoInitialToken(object,
responseToken,
responseTokenLength,
(unsigned char**)&spnegoToken.value,
&spnegoToken.length)) {
Curl_safefree(responseToken);
ASN1_OBJECT_free(object);
infof(conn->data, "Make SPNEGO Initial Token failed\n");
}
else if(!spnegoToken.value || !spnegoToken.length) {
Curl_safefree(responseToken);
ASN1_OBJECT_free(object);
if(spnegoToken.value)
gss_release_buffer(&discard_st, &spnegoToken);
infof(conn->data, "Make SPNEGO Initial Token succeeded (NULL token)\n");
}
else {
Curl_safefree(responseToken);
ASN1_OBJECT_free(object);
gss_release_buffer(&discard_st, &neg_ctx->output_token);
neg_ctx->output_token.value = spnegoToken.value;
neg_ctx->output_token.length = spnegoToken.length;
infof(conn->data, "Make SPNEGO Initial Token succeeded\n");
}
}
#endif
error = Curl_base64_encode(conn->data,
neg_ctx->output_token.value,
neg_ctx->output_token.length,

View File

@ -268,9 +268,6 @@ static curl_version_info_data version_info = {
#ifdef CURLRES_ASYNCH
| CURL_VERSION_ASYNCHDNS
#endif
#ifdef HAVE_SPNEGO
| CURL_VERSION_SPNEGO
#endif
#if (CURL_SIZEOF_CURL_OFF_T > 4) && \
( (SIZEOF_OFF_T > 4) || defined(USE_WIN32_LARGE_FILES) )
| CURL_VERSION_LARGEFILE

View File

@ -81,9 +81,9 @@ case $dirmode in
echo "mkdir -p -- $*"
exec mkdir -p -- "$@"
else
# On NextStep and OpenStep, the `mkdir' command does not
# On NextStep and OpenStep, the 'mkdir' command does not
# recognize any option. It will interpret all options as
# directories to create, and then abort because `.' already
# directories to create, and then abort because '.' already
# exists.
test -d ./-p && rmdir ./-p
test -d ./--version && rmdir ./--version

View File

@ -148,9 +148,6 @@ endif
ifeq ($(findstring -sspi,$(CFG)),-sspi)
SSPI = 1
endif
ifeq ($(findstring -spnego,$(CFG)),-spnego)
SPNEGO = 1
endif
ifeq ($(findstring -ldaps,$(CFG)),-ldaps)
LDAPS = 1
endif
@ -258,9 +255,6 @@ ifdef SSPI
CFLAGS += -DUSE_SCHANNEL
endif
endif
ifdef SPNEGO
CFLAGS += -DHAVE_SPNEGO
endif
ifdef IPV6
CFLAGS += -DENABLE_IPV6 -D_WIN32_WINNT=0x0501
endif

View File

@ -226,10 +226,6 @@ endif
ifeq ($(findstring -idn,$(CFG)),-idn)
WITH_IDN = 1
endif
ifeq ($(findstring -spnego,$(CFG)),-spnego)
WITH_SPNEGO = 1
WITH_SSL = 1
endif
ifeq ($(findstring -metalink,$(CFG)),-metalink)
WITH_METALINK = 1
WITH_SSL = 1
@ -267,10 +263,6 @@ ifdef WITH_SSL
LDLIBS += $(OPENSSL_PATH)/out_nw_$(LIBARCH_L)/ssl.$(LIBEXT)
LDLIBS += $(OPENSSL_PATH)/out_nw_$(LIBARCH_L)/crypto.$(LIBEXT)
IMPORTS += GetProcessSwitchCount RunningProcess
ifdef WITH_SPNEGO
# INCLUDES += -I$(FBOPENSSL_PATH)/include
LDLIBS += $(FBOPENSSL_PATH)/nw/fbopenssl.$(LIBEXT)
endif
else
ifdef WITH_AXTLS
# INCLUDES += -I$(AXTLS_PATH)/inc

View File

@ -264,7 +264,6 @@ static const struct feat feats[] = {
{"Largefile", CURL_VERSION_LARGEFILE},
{"NTLM", CURL_VERSION_NTLM},
{"NTLM_WB", CURL_VERSION_NTLM_WB},
{"SPNEGO", CURL_VERSION_SPNEGO},
{"SSL", CURL_VERSION_SSL},
{"SSPI", CURL_VERSION_SSPI},
{"krb4", CURL_VERSION_KERBEROS4},

View File

@ -28,7 +28,6 @@ CFGSET=true
!MESSAGE http://www.microsoft.com/downloads/details.aspx?FamilyID=AD6158D7-DDBA-416A-9109-07607425A815
!MESSAGE ENABLE_IPV6=<yes or no> - Enable IPv6, defaults to yes
!MESSAGE ENABLE_SSPI=<yes or no> - Enable SSPI support, defaults to yes
!MESSAGE ENABLE_SPNEGO=<yes or no> - Enable Simple and Protected GSSAPI Negotiation Mechanism, defaults to yes
!MESSAGE ENABLE_WINSSL=<yes or no> - Enable native Windows SSL support, defaults to yes
!MESSAGE GEN_PDB=<yes or no> - Generate Program Database (debug symbols for release build)
!MESSAGE DEBUG=<yes or no> - Debug builds
@ -86,14 +85,6 @@ USE_SSPI = true
USE_SSPI = false
!ENDIF
!IFNDEF ENABLE_SPNEGO
USE_SPNEGO = true
!ELSEIF "$(ENABLE_SPNEGO)"=="yes"
USE_SPNEGO = true
!ELSEIF "$(ENABLE_SPNEGO)"=="no"
USE_SPNEGO = false
!ENDIF
!IFNDEF ENABLE_WINSSL
!IFDEF WITH_SSL
USE_WINSSL = false
@ -166,10 +157,6 @@ CONFIG_NAME_LIB = $(CONFIG_NAME_LIB)-ipv6
CONFIG_NAME_LIB = $(CONFIG_NAME_LIB)-sspi
!ENDIF
!IF "$(USE_SPNEGO)"=="true"
CONFIG_NAME_LIB = $(CONFIG_NAME_LIB)-spnego
!ENDIF
!IF "$(USE_WINSSL)"=="true"
CONFIG_NAME_LIB = $(CONFIG_NAME_LIB)-winssl
!ENDIF
@ -197,7 +184,6 @@ $(MODE):
@SET USE_IDN=$(USE_IDN)
@SET USE_IPV6=$(USE_IPV6)
@SET USE_SSPI=$(USE_SSPI)
@SET USE_SPNEGO=$(USE_SPNEGO)
@SET USE_WINSSL=$(USE_WINSSL)
@$(MAKE) /NOLOGO /F MakefileBuild.vc

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@ -187,17 +187,6 @@ SSPI_CFLAGS = $(SSPI_CFLAGS) /DUSE_WINDOWS_SSPI
!ENDIF
!IFNDEF USE_SPNEGO
USE_SPNEGO = true
!ELSEIF "$(USE_SPNEGO)"=="yes"
USE_SPNEGO = true
!ENDIF
!IF "$(USE_SPNEGO)"=="true"
SPNEGO_CFLAGS = $(SPNEGO_CFLAGS) /DHAVE_SPNEGO
!ENDIF
!IFNDEF USE_WINSSL
!IF "$(USE_SSL)"=="true"
USE_WINSSL = false
@ -330,10 +319,6 @@ CFLAGS = $(CFLAGS) $(IPV6_CFLAGS)
CFLAGS = $(CFLAGS) $(SSPI_CFLAGS)
!ENDIF
!IF "$(USE_SPNEGO)"=="true"
CFLAGS = $(CFLAGS) $(SPNEGO_CFLAGS)
!ENDIF
!IF "$(GEN_PDB)"=="true"
CFLAGS = $(CFLAGS) $(CFLAGS_PDB) /Fd"$(LIB_DIROBJ)\$(PDB)"
LFLAGS = $(LFLAGS) $(LFLAGS_PDB)
@ -396,7 +381,6 @@ $(TARGET): $(LIB_OBJS) $(LIB_DIROBJ) $(DISTDIR)
@echo Using IDN: $(USE_IDN)
@echo Using IPv6: $(USE_IPV6)
@echo Using SSPI: $(USE_SSPI)
@echo Using SPNEGO: $(USE_SPNEGO)
@echo Using WinSSL: $(USE_WINSSL)
@echo CFLAGS: $(CFLAGS)
@echo LFLAGS: $(LFLAGS)