Configure libtls and nc(1) to statically link to libcrypto/ssl

An issue that Reyk Floeter noted while building a Debian package for
LibreSSL is that installing libtls along with OpenSSL causes linker
issues since it will often pick up the wrong libcrypto/libssl. This
change makes libtls statically link the object files it needs rather
than relying on the shared libraries, effectively making libtls
self-contained and able to be packaged independently.

This should make it possible for other projects that also use libtls to
be able to package support without requiring the target OS to ship
libcrypto / libssl from LibreSSL.

https://salsa.debian.org/reyk-guest/libressl/-/commit/678278df55ce866f2f363998ca690442fa786c66

4 files changed, 8 insertions, 10 deletions

diff --git a/apps/nc/Makefile.am b/apps/nc/Makefile.am
index 4b5b561..135ff4b 100644
--- a/apps/nc/Makefile.am
+++ b/apps/nc/Makefile.am
@@ -12,9 +12,9 @@ endif
 EXTRA_DIST = nc.1
 EXTRA_DIST += CMakeLists.txt
 
-nc_LDADD = $(abs_top_builddir)/crypto/libcrypto.la
-nc_LDADD += $(abs_top_builddir)/ssl/libssl.la
-nc_LDADD += $(abs_top_builddir)/tls/libtls.la
+nc_LDFLAGS = $(abs_top_builddir)/crypto/.libs/libcompat.a
+
+nc_LDADD = $(abs_top_builddir)/tls/libtls.la
 nc_LDADD += $(PLATFORM_LDADD) $(PROG_LDADD)
 
 AM_CPPFLAGS += -I$(top_srcdir)/apps/nc/compat
diff --git a/configure.ac b/configure.ac
index 75b88fe..3aca617 100644
--- a/configure.ac
+++ b/configure.ac
@@ -29,8 +29,7 @@ USER_CFLAGS="$CFLAGS"
 AC_PROG_CC([cc gcc])
 AC_PROG_CC_STDC
 AM_PROG_CC_C_O
-AC_PROG_LIBTOOL
-LT_INIT
+LT_INIT([pic-only])
 
 CHECK_OS_OPTIONS
 
diff --git a/libtls.pc.in b/libtls.pc.in
index 82a6a71..0d4e625 100644
--- a/libtls.pc.in
+++ b/libtls.pc.in
@@ -9,8 +9,7 @@ Name: LibreSSL-libtls
 Description: Secure communications using the TLS socket protocol.
 Version: @VERSION@
 Requires:
-Requires.private: libcrypto libssl
 Conflicts:
 Libs: -L${libdir} -ltls
-Libs.private: @LIBS@ -lcrypto -lssl @PLATFORM_LDADD@
+Libs.private: @LIBS@ @PLATFORM_LDADD@
 Cflags: -I${includedir}
diff --git a/tls/Makefile.am b/tls/Makefile.am
index 942abf9..c4790a4 100644
--- a/tls/Makefile.am
+++ b/tls/Makefile.am
@@ -7,9 +7,9 @@ EXTRA_DIST += CMakeLists.txt
 EXTRA_DIST += tls.sym
 
 libtls_la_LDFLAGS = -version-info @LIBTLS_VERSION@ -no-undefined -export-symbols $(top_srcdir)/tls/tls.sym
-libtls_la_LIBADD = $(abs_top_builddir)/ssl/libssl.la
-libtls_la_LIBADD += $(abs_top_builddir)/crypto/libcrypto.la
-libtls_la_LIBADD += $(PLATFORM_LDADD)
+libtls_la_LDFLAGS += $(abs_top_builddir)/ssl/.libs/libssl.a
+libtls_la_LDFLAGS += $(abs_top_builddir)/crypto/.libs/libcrypto.a
+libtls_la_LIBADD = $(PLATFORM_LDADD)
 
 libtls_la_CPPFLAGS = $(AM_CPPFLAGS)
 if OPENSSLDIR_DEFINED