nfs-utils: Include legacy or TI-RPC headers, not both

Data type incompatibilities between the legacy RPC headers and the
TI-RPC headers mean we can't use libtirpc with code that was compiled
against the legacy RPC headers.  The definition of rpcprog_t for
example is "unsigned long" in the legacy library, but it's "uint32_t"
for TI-RPC.  On 32-bit systems, these types happen to have the same
width, but on 64-bit systems they don't, making more complex data
structures that use these types in fields ABI incompatible.

Adopt a new strategy to deal with this issue.  When --enable-tirpc is
set, append "-I/usr/include/tirpc" to the compilation steps.  This
should cause the compiler to grab the tirpc/ headers instead of the
legacy headers.  Now, for TI-RPC builds, the TI-RPC legacy functions
and the TI-RPC headers will be used.  On legacy systems, the legacy
headers and legacy glibc RPC implementation will be used.

A new ./configure option is introduced to allow system integrators to
use TI-RPC headers in some other location than /usr/include/tirpc.
/usr/include/tirpc remains the default setting for this new option.

The gssd implementation presents a few challenges, but it turns out
the gssglue library is similar to the auth_gss pieces of TI-RPC.  To
avoid similar header incompatibility issues, gssd now uses libtirpc
instead of libgssglue if --enable-tirpc is specified.  There may be
other issues to tackle with gssd, but for now, we just make sure it
builds with --enable-tirpc.

Note also: svc_getcaller() is a macro in both cases that points to
a sockaddr field in the svc_req structure.  The legacy version points
to a sockaddr_in type field, but the TI-RPC version points to a
sockaddr_in6 type field.

rpc.mountd unconditionally casts the result of svc_getcaller() to a
sockaddr_in *.  This should be OK for TI-RPC as well, since rpc.mountd
still uses legacy RPC calls (provided by glibc, or emulated by TI-RPC)
to set up its listeners, and therefore rpc.mountd callers will always
be from AF_INET addresses for now.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Steve Dickson <steved@redhat.com>

3 files changed, 25 insertions, 9 deletions

diff --git a/aclocal/librpcsecgss.m4 b/aclocal/librpcsecgss.m4
index 5791260..d1dd25e 100644
--- a/aclocal/librpcsecgss.m4
+++ b/aclocal/librpcsecgss.m4
@@ -3,12 +3,17 @@ dnl KRB5LIBS must be set before this function is invoked.
 dnl
 AC_DEFUN([AC_LIBRPCSECGSS], [
 
-  dnl Check for library, but do not add -lrpcsecgss to LIBS
-  AC_CHECK_LIB([rpcsecgss], [authgss_create_default], [librpcsecgss=1],
-               [AC_MSG_ERROR([librpcsecgss not found.])])
+  dnl libtirpc provides an rpcsecgss API
+  if test "$enable_tirpc" = no; then
 
-  AC_CHECK_LIB([rpcsecgss], [authgss_set_debug_level],
-               [AC_DEFINE([HAVE_AUTHGSS_SET_DEBUG_LEVEL], 1,
-               [Define to 1 if you have the `authgss_set_debug_level' function.])])
+    dnl Check for library, but do not add -lrpcsecgss to LIBS
+    AC_CHECK_LIB([rpcsecgss], [authgss_create_default], [librpcsecgss=1],
+                 [AC_MSG_ERROR([librpcsecgss not found.])])
+
+    AC_CHECK_LIB([rpcsecgss], [authgss_set_debug_level],
+                 [AC_DEFINE([HAVE_AUTHGSS_SET_DEBUG_LEVEL], 1,
+                 [Define to 1 if you have the `authgss_set_debug_level' function.])])
+
+  fi
 
 ])dnl
diff --git a/aclocal/libtirpc.m4 b/aclocal/libtirpc.m4
index b1f3669..af4c7d3 100644
--- a/aclocal/libtirpc.m4
+++ b/aclocal/libtirpc.m4
@@ -2,6 +2,12 @@ dnl Checks for TI-RPC library and headers
 dnl
 AC_DEFUN([AC_LIBTIRPC], [
 
+  AC_ARG_WITH([tirpcinclude],
+              [AC_HELP_STRING([--with-tirpcinclude=DIR],
+                              [use TI-RPC headers in DIR])],
+              [tirpc_header_dir=$withval],
+              [tirpc_header_dir=/usr/include/tirpc])
+
   dnl if --enable-tirpc was specifed, the following components
   dnl must be present, and we set up HAVE_ macros for them.
 
@@ -12,8 +18,10 @@ AC_DEFUN([AC_LIBTIRPC], [
                  [AC_MSG_ERROR([libtirpc not found.])])
 
     dnl also must have the headers installed where we expect
-    AC_CHECK_HEADERS([tirpc/netconfig.h], ,
+    dnl look for headers; add -I compiler option if found
+    AC_CHECK_HEADERS([${tirpc_header_dir}/netconfig.h], ,
                      [AC_MSG_ERROR([libtirpc headers not found.])])
+    AC_SUBST([AM_CPPFLAGS], ["-I${tirpc_header_dir}"])
 
   fi
 
diff --git a/aclocal/rpcsec_vers.m4 b/aclocal/rpcsec_vers.m4
index df7cfb9..5d13db3 100644
--- a/aclocal/rpcsec_vers.m4
+++ b/aclocal/rpcsec_vers.m4
@@ -1,8 +1,11 @@
 dnl Checks librpcsec version
 AC_DEFUN([AC_RPCSEC_VERSION], [
 
-  PKG_CHECK_MODULES([RPCSECGSS], [librpcsecgss >= 0.16], ,
-                    [AC_MSG_ERROR([Unable to locate information required to use librpcsecgss.  If you have pkgconfig installed, you might try setting environment variable PKG_CONFIG_PATH to /usr/local/lib/pkgconfig])])
+  dnl TI-RPC replaces librpcsecgss
+  if test "$enable_tirpc" = no; then
+    PKG_CHECK_MODULES([RPCSECGSS], [librpcsecgss >= 0.16], ,
+                      [AC_MSG_ERROR([Unable to locate information required to use librpcsecgss.  If you have pkgconfig installed, you might try setting environment variable PKG_CONFIG_PATH to /usr/local/lib/pkgconfig])])
+  fi
 
   PKG_CHECK_MODULES([GSSGLUE], [libgssglue >= 0.1])