Bug 20918 - Building with --enable-nss-crypt fails tst-linkall-static

Some configurations may use NSS cryptographic routines but have no
static library for those routines. The following changes allow glibc to
be built and tested with --enable-nss-crypt, but without having a static
NSS library. At a high level the change does two things:

(1) Detect at configure time if static NSS crypto libraries are
    available.  Assumes libfreebl3.a (instead of the existing Fedora
    libfreebl.a which is incomplete) which matches libfreebl3.so.

(2) If static NSS crypto libraries are _not_ available then adjust the
    way in which we build tst-linkall-static. This includes excluding a
    reference to crypt and not linking against libcrypt.a, all of which
    will fail otherwise.

Testing assumptions:
* Static library is named libfreebl3.a (not libfreebl.a as is currently
  provided in Fedora), matching libfreebl3.so shared link name.

Tested on x86_64 on Fedora with:

(a) --enable-nss-crypt, with no static NSS library support: PASS
    (previous FAIL)

(b) --enable-nss-crypt, with faked static NSS library support: PASS
    (unsupported)
	* Requires changing elf/Makefile to include a stub
	  /lib64/libfreebl3.a for testing purposes.

(c) --disable-nss-crypt: PASS
    (default)

No regressions on x86_64.

For details see:
https://www.sourceware.org/ml/libc-alpha/2016-11/msg00647.html

diff --git a/ChangeLog b/ChangeLog
index 95b5c7eb1a6f79ad3b294c026ce7cac2bd7280f6..e4a41d6a3c620cee8192f051e075e4c2ff14a6b7 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,19 @@
+2016-12-02  Carlos O'Donell  <carlos@redhat.com>
+
+       [BZ #20918]
+       * configure.ac: Test for static NSS cryptographic libraries and set
+       libc_cv_static_nss_crypt.
+       * configure: Regenerate.
+       * config.make.in (static-nss-crypt): Define.
+       * elf/Makefile (CFLAGS-tst-linkall-static.c): Define.
+       [ifeq (yesno,$(nss-crypt)$(static-nss-crypt))]
+       (CFLAGS-tst-linkall-static.c): Define.
+       ($(objpfx)tst-linkall-static): Remove libcrypt.a.
+       [ifeq (yesyes,$(nss-crypt)$(static-nss-crypt))]
+       ($(objpfx)tst-linkall-static): Define.
+       [ifeq (no,$(nss-crypt))] ($(objpfx)tst-linkall-static): Define.
+       * elf/tst-linkall-static.c [USE_CRYPT](references): Reference crypt().
+
 2016-12-02  Florian Weimer  <fweimer@redhat.com>
 
        * elf/Makefile [build-shared] (tests): Add tst-latepthread.

diff --git a/config.make.in b/config.make.in
index 04a8b3ed7f06f2b244c07f75ae6f6f328c5b1a3d..d2d9b8ab36895f8bd2be41e8638cc3e9b9fa1875 100644 (file)
--- a/config.make.in
+++ b/config.make.in
@@ -75,6 +75,7 @@ multi-arch = @multi_arch@
 mach-interface-list = @mach_interface_list@
 
 nss-crypt = @libc_cv_nss_crypt@
+static-nss-crypt = @libc_cv_static_nss_crypt@
 
 # Configuration options.
 build-shared = @shared@

diff --git a/configure b/configure
index d9f8c06bca80faba35c506c452aed796c77aa97d..5cf3230b5627ccbe0911d8d94374a0664152ce80 100755 (executable)
--- a/configure
+++ b/configure
@@ -665,6 +665,7 @@ add_ons
 build_pt_chown
 build_nscd
 link_obsolete_rpc
+libc_cv_static_nss_crypt
 libc_cv_nss_crypt
 enable_werror
 all_warnings
@@ -3529,6 +3530,7 @@ cannot find NSS headers with lowlevel hash function interfaces" "$LINENO" 5
 fi
 rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
   old_LIBS="$LIBS"
+  old_LDFLAGS="$LDFLAGS"
   LIBS="$LIBS -lfreebl3"
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
@@ -3551,14 +3553,41 @@ cannot link program using lowlevel NSS hash functions" "$LINENO" 5
 fi
 rm -f core conftest.err conftest.$ac_objext \
     conftest$ac_exeext conftest.$ac_ext
+  # Check to see if there is a static NSS cryptographic library.
+  # If there isn't then we can't link anything with libcrypt.a,
+  # and that might mean disabling some static tests.
+  LDFLAGS="$LDFLAGS -static"
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+typedef int PRBool;
+#include <hasht.h>
+#include <nsslowhash.h>
+int
+main ()
+{
+NSSLOW_Init();
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  libc_cv_static_nss_crypt=yes
+else
+  libc_cv_static_nss_crypt=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+  LDFLAGS="$old_LDFLAGS"
   CFLAGS="$old_CFLAGS"
   LIBS="$old_LIBS"
 else
   libc_cv_nss_crypt=no
+  libc_cv_static_nss_crypt=no
 fi
 
 
 
+
 # Check whether --enable-obsolete-rpc was given.
 if test "${enable_obsolete_rpc+set}" = set; then :
   enableval=$enable_obsolete_rpc; link_obsolete_rpc=$enableval

diff --git a/configure.ac b/configure.ac
index de0a40f1a7d8c0d5f18a991586de25b51fdb6aad..d719fadeef3f438683c4261be673c66a40e614b1 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -321,6 +321,7 @@ void f (void) { NSSLOW_Init (); }])],
             AC_MSG_ERROR([
 cannot find NSS headers with lowlevel hash function interfaces]))
   old_LIBS="$LIBS"
+  old_LDFLAGS="$LDFLAGS"
   LIBS="$LIBS -lfreebl3"
   AC_LINK_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
 #include <hasht.h>
@@ -329,12 +330,25 @@ cannot find NSS headers with lowlevel hash function interfaces]))
                 libc_cv_nss_crypt=yes,
                 AC_MSG_ERROR([
 cannot link program using lowlevel NSS hash functions]))
+  # Check to see if there is a static NSS cryptographic library.
+  # If there isn't then we can't link anything with libcrypt.a,
+  # and that might mean disabling some static tests.
+  LDFLAGS="$LDFLAGS -static"
+  AC_LINK_IFELSE([AC_LANG_PROGRAM([typedef int PRBool;
+#include <hasht.h>
+#include <nsslowhash.h>],
+                                 [NSSLOW_Init();])],
+                libc_cv_static_nss_crypt=yes,
+                libc_cv_static_nss_crypt=no)
+  LDFLAGS="$old_LDFLAGS"
   CFLAGS="$old_CFLAGS"
   LIBS="$old_LIBS"
 else
   libc_cv_nss_crypt=no
+  libc_cv_static_nss_crypt=no
 fi
 AC_SUBST(libc_cv_nss_crypt)
+AC_SUBST(libc_cv_static_nss_crypt)
 
 
 AC_ARG_ENABLE([obsolete-rpc],

diff --git a/elf/Makefile b/elf/Makefile
index ebdcbc6ff4ee35765b2414c1a74da47353d8b96b..f57927f40377ded3326a8bd42f885ed3cba5bffe 100644 (file)
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -337,6 +337,16 @@ $(objpfx)tst-_dl_addr_inside_object: $(objpfx)dl-addr-obj.os
 CFLAGS-tst-_dl_addr_inside_object.c += $(PIE-ccflag)
 endif
 
+# By default tst-linkall-static should try to use crypt routines to test
+# static libcrypt use.
+CFLAGS-tst-linkall-static.c = -DUSE_CRYPT=1
+# However, if we are using NSS crypto and we don't have a static
+# library, then we exclude the use of crypt functions in the test.
+# We similarly exclude libcrypt.a from the static link (see below).
+ifeq (yesno,$(nss-crypt)$(static-nss-crypt))
+CFLAGS-tst-linkall-static.c = -DUSE_CRYPT=0
+endif
+
 include ../Rules
 
 ifeq (yes,$(build-shared))
@@ -1307,12 +1317,30 @@ $(objpfx)tst-ldconfig-X.out : tst-ldconfig-X.sh $(objpfx)ldconfig
 
 $(objpfx)tst-dlsym-error: $(libdl)
 
+# Test static linking of all the libraries we can possibly link
+# together.  Note that in some configurations this may be less than the
+# complete list of libraries we build but we try to maxmimize this list.
 $(objpfx)tst-linkall-static: \
   $(common-objpfx)math/libm.a \
-  $(common-objpfx)crypt/libcrypt.a \
   $(common-objpfx)resolv/libresolv.a \
   $(common-objpfx)dlfcn/libdl.a \
   $(common-objpfx)login/libutil.a \
   $(common-objpfx)rt/librt.a \
   $(common-objpfx)resolv/libanl.a \
-  $(static-thread-library) \
+  $(static-thread-library)
+
+# If we are using NSS crypto and we have the ability to link statically
+# then we include libcrypt.a, otherwise we leave out libcrypt.a and
+# link as much as we can into the tst-linkall-static test.  This assumes
+# that linking with libcrypt.a does everything required to include the
+# static NSS crypto library.
+ifeq (yesyes,$(nss-crypt)$(static-nss-crypt))
+$(objpfx)tst-linkall-static: \
+  $(common-objpfx)crypt/libcrypt.a
+endif
+# If we are not using NSS crypto then we always have the ability to link
+# with libcrypt.a.
+ifeq (no,$(nss-crypt))
+$(objpfx)tst-linkall-static: \
+  $(common-objpfx)crypt/libcrypt.a
+endif

diff --git a/elf/tst-linkall-static.c b/elf/tst-linkall-static.c
index 7a4aaccf58867242e902c43a7069ca4dff3b167e..cc77f0788edaf2dd10817620f6dd2743ed4b7e5f 100644 (file)
--- a/elf/tst-linkall-static.c
+++ b/elf/tst-linkall-static.c
@@ -32,7 +32,9 @@ void *references[] =
   {
     &pow,                       /* libm */
     &pthread_create,            /* libpthread */
+#if USE_CRYPT
     &crypt,                     /* libcrypt */
+#endif
     &res_send,                  /* libresolv */
     &dlopen,                    /* libdl */
     &login,                     /* libutil */