Implement TPMLIB_ValidateState() to test state blobs early

Implement TPMLIB_ValidateState(), which is supposed to be used
for checking usability of state blobs before TPMLIB_MainInit()
is called or TPM_Startup has been sent to the TPM.

This function is useful to be called once TPM state blobs
have been migrated to a destination and we need to check
whether libtpms can use these state blobs and if not
we have a chance to fall back to the migration source host.

Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>

include/libtpms/tpm_library.h

@@ -136,6 +136,15 @@ uint32_t TPMLIB_SetBufferSize(uint32_t wanted_size,
                               uint32_t *min_size,
                               uint32_t *max_size);
 
+enum TPMLIB_StateType {
+    TPMLIB_STATE_PERMANENT  = (1 << 0),
+    TPMLIB_STATE_VOLATILE   = (1 << 1),
+    TPMLIB_STATE_SAVE_STATE = (1 << 2),
+};
+
+TPM_RESULT TPMLIB_ValidateState(enum TPMLIB_StateType st,
+                                unsigned int flags);
+
 #ifdef __cplusplus
 }
 #endif

include/libtpms/tpm_library.h.in

@@ -136,6 +136,15 @@ uint32_t TPMLIB_SetBufferSize(uint32_t wanted_size,
                               uint32_t *min_size,
                               uint32_t *max_size);
 
+enum TPMLIB_StateType {
+    TPMLIB_STATE_PERMANENT  = (1 << 0),
+    TPMLIB_STATE_VOLATILE   = (1 << 1),
+    TPMLIB_STATE_SAVE_STATE = (1 << 2),
+};
+
+TPM_RESULT TPMLIB_ValidateState(enum TPMLIB_StateType st,
+                                unsigned int flags);
+
 #ifdef __cplusplus
 }
 #endif

man/man3/Makefile.am

@@ -16,6 +16,7 @@ man3_PODS = \
 	TPMLIB_RegisterCallbacks.pod \
 	TPMLIB_SetBufferSize.pod \
 	TPMLIB_SetDebugFD.pod \
+	TPMLIB_ValidateState.pod \
 	TPMLIB_VolatileAll_Store.pod \
 	TPM_Malloc.pod
 
@@ -39,6 +40,7 @@ man3_MANS += \
 	TPMLIB_SetDebugFD.3 \
 	TPMLIB_SetBufferSize.3 \
 	TPMLIB_RegisterCallbacks.3 \
+	TPMLIB_ValidateState.3 \
 	TPMLIB_VolatileAll_Store.3 \
 	TPM_Malloc.3
 

man/man3/TPMLIB_ValidateState.3

@@ -0,0 +1,173 @@
+.\" Automatically generated by Pod::Man 2.28 (Pod::Simple 3.31)
+.\"
+.\" Standard preamble:
+.\" ========================================================================
+.de Sp \" Vertical space (when we can't use .PP)
+.if t .sp .5v
+.if n .sp
+..
+.de Vb \" Begin verbatim text
+.ft CW
+.nf
+.ne \\$1
+..
+.de Ve \" End verbatim text
+.ft R
+.fi
+..
+.\" Set up some character translations and predefined strings.  \*(-- will
+.\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left
+.\" double quote, and \*(R" will give a right double quote.  \*(C+ will
+.\" give a nicer C++.  Capital omega is used to do unbreakable dashes and
+.\" therefore won't be available.  \*(C` and \*(C' expand to `' in nroff,
+.\" nothing in troff, for use with C<>.
+.tr \(*W-
+.ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p'
+.ie n \{\
+.    ds -- \(*W-
+.    ds PI pi
+.    if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch
+.    if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\"  diablo 12 pitch
+.    ds L" ""
+.    ds R" ""
+.    ds C` ""
+.    ds C' ""
+'br\}
+.el\{\
+.    ds -- \|\(em\|
+.    ds PI \(*p
+.    ds L" ``
+.    ds R" ''
+.    ds C`
+.    ds C'
+'br\}
+.\"
+.\" Escape single quotes in literal strings from groff's Unicode transform.
+.ie \n(.g .ds Aq \(aq
+.el       .ds Aq '
+.\"
+.\" If the F register is turned on, we'll generate index entries on stderr for
+.\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index
+.\" entries marked with X<> in POD.  Of course, you'll have to process the
+.\" output yourself in some meaningful fashion.
+.\"
+.\" Avoid warning from groff about undefined register 'F'.
+.de IX
+..
+.nr rF 0
+.if \n(.g .if rF .nr rF 1
+.if (\n(rF:(\n(.g==0)) \{
+.    if \nF \{
+.        de IX
+.        tm Index:\\$1\t\\n%\t"\\$2"
+..
+.        if !\nF==2 \{
+.            nr % 0
+.            nr F 2
+.        \}
+.    \}
+.\}
+.rr rF
+.\"
+.\" Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2).
+.\" Fear.  Run.  Save yourself.  No user-serviceable parts.
+.    \" fudge factors for nroff and troff
+.if n \{\
+.    ds #H 0
+.    ds #V .8m
+.    ds #F .3m
+.    ds #[ \f1
+.    ds #] \fP
+.\}
+.if t \{\
+.    ds #H ((1u-(\\\\n(.fu%2u))*.13m)
+.    ds #V .6m
+.    ds #F 0
+.    ds #[ \&
+.    ds #] \&
+.\}
+.    \" simple accents for nroff and troff
+.if n \{\
+.    ds ' \&
+.    ds ` \&
+.    ds ^ \&
+.    ds , \&
+.    ds ~ ~
+.    ds /
+.\}
+.if t \{\
+.    ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u"
+.    ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u'
+.    ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u'
+.    ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u'
+.    ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u'
+.    ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u'
+.\}
+.    \" troff and (daisy-wheel) nroff accents
+.ds : \\k:\h'-(\\n(.wu*8/10-\*(#H+.1m+\*(#F)'\v'-\*(#V'\z.\h'.2m+\*(#F'.\h'|\\n:u'\v'\*(#V'
+.ds 8 \h'\*(#H'\(*b\h'-\*(#H'
+.ds o \\k:\h'-(\\n(.wu+\w'\(de'u-\*(#H)/2u'\v'-.3n'\*(#[\z\(de\v'.3n'\h'|\\n:u'\*(#]
+.ds d- \h'\*(#H'\(pd\h'-\w'~'u'\v'-.25m'\f2\(hy\fP\v'.25m'\h'-\*(#H'
+.ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u'
+.ds th \*(#[\v'.3m'\s+1I\s-1\v'-.3m'\h'-(\w'I'u*2/3)'\s-1o\s+1\*(#]
+.ds Th \*(#[\s+2I\s-2\h'-\w'I'u*3/5'\v'-.3m'o\v'.3m'\*(#]
+.ds ae a\h'-(\w'a'u*4/10)'e
+.ds Ae A\h'-(\w'A'u*4/10)'E
+.    \" corrections for vroff
+.if v .ds ~ \\k:\h'-(\\n(.wu*9/10-\*(#H)'\s-2\u~\d\s+2\h'|\\n:u'
+.if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u'
+.    \" for low resolution devices (crt and lpr)
+.if \n(.H>23 .if \n(.V>19 \
+\{\
+.    ds : e
+.    ds 8 ss
+.    ds o a
+.    ds d- d\h'-1'\(ga
+.    ds D- D\h'-1'\(hy
+.    ds th \o'bp'
+.    ds Th \o'LP'
+.    ds ae ae
+.    ds Ae AE
+.\}
+.rm #[ #] #H #V #F C
+.\" ========================================================================
+.\"
+.IX Title "TPMLIB_ValidateState 3"
+.TH TPMLIB_ValidateState 3 "2018-02-17" "libtpms" ""
+.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
+.\" way too many mistakes in technical documents.
+.if n .ad l
+.nh
+.SH "NAME"
+TPMLIB_ValidateState  \- Validate the state blobs of the TPM
+.SH "LIBRARY"
+.IX Header "LIBRARY"
+\&\s-1TPM\s0 library (libtpms, \-ltpms)
+.SH "SYNOPSIS"
+.IX Header "SYNOPSIS"
+\&\fB#include <libtpms/tpm_library.h\fR>
+.PP
+\&\fBuint32_t TPMLIB_ValidateState(TPMLIB_StateType st,
+                              unsigned int flags);
+\&\fR
+.SH "DESCRIPTION"
+.IX Header "DESCRIPTION"
+The \fB\f(BITPMLIB_ValidateState()\fB\fR function allows to validate the
+state blobs that the \s-1TPM\s0 would read upon \fB\f(BITPMLIB_MainInit()\fB\fR or
+once the TPM_Startup command has been sent to it.
+.PP
+This function is useful for \s-1TPM\s0 state migration between possibly
+different version of libtpms. Here the target libtpms needs to be
+able to determine whether it can support the version of blobs that were
+migrated and if this is not the case, the caller can refuse the
+migration.
+.PP
+The \fBtpmlib_state\fR parameter can be a logical 'or' of one or
+multiple of of the following: \fB\s-1TPMLIB_STATE_PERMANENT\s0\fR,
+\&\fB\s-1TPMLIB_STATE_VOLATILE\s0\fR, or \fB\s-1TPMLIB_STATE_SAVE_STATE\s0\fR.
+The \fBflags\fR parameter is curretnly not used and should be set to 0.
+.PP
+This function should be called before \fB\f(BITPMLIB_MainInit()\fB\fR is invoked.
+.SH "SEE ALSO"
+.IX Header "SEE ALSO"
+\&\fBTPMLIB_MainInit\fR(3), \fBTPMLIB_Terminate\fR(3)

man/man3/TPMLIB_ValidateState.pod

@@ -0,0 +1,40 @@
+=head1 NAME
+
+TPMLIB_ValidateState  - Validate the state blobs of the TPM
+
+=head1 LIBRARY
+
+TPM library (libtpms, -ltpms)
+
+=head1 SYNOPSIS
+
+B<#include <libtpms/tpm_library.h>>
+
+B<uint32_t TPMLIB_ValidateState(TPMLIB_StateType st,
+                              unsigned int flags);
+>
+
+=head1 DESCRIPTION
+
+The B<TPMLIB_ValidateState()> function allows to validate the
+state blobs that the TPM would read upon B<TPMLIB_MainInit()> or
+once the TPM_Startup command has been sent to it.
+
+This function is useful for TPM state migration between possibly
+different version of libtpms. Here the target libtpms needs to be
+able to determine whether it can support the version of blobs that were
+migrated and if this is not the case, the caller can refuse the
+migration.
+
+The B<tpmlib_state> parameter can be a logical 'or' of one or
+multiple of of the following: B<TPMLIB_STATE_PERMANENT>,
+B<TPMLIB_STATE_VOLATILE>, or B<TPMLIB_STATE_SAVE_STATE>.
+The B<flags> parameter is curretnly not used and should be set to 0.
+
+This function should be called before B<TPMLIB_MainInit()> is invoked.
+
+=head1 SEE ALSO
+
+B<TPMLIB_MainInit>(3), B<TPMLIB_Terminate>(3)
+
+=cut

src/libtpms.syms

@@ -27,6 +27,7 @@ LIBTPMS_0.6.0 {
 	TPMLIB_SetDebugFD;
 	TPMLIB_SetDebugLevel;
 	TPMLIB_SetDebugPrefix;
+	TPMLIB_ValidateState;
     local:
 	*;
 } LIBTPMS_0.5.1;

src/tpm_library.c

@@ -172,6 +172,12 @@ uint32_t TPMLIB_SetBufferSize(uint32_t wanted_size,
     return tpm_iface[0]->SetBufferSize(wanted_size, min_size, max_size);
 }
 
+TPM_RESULT TPMLIB_ValidateState(enum TPMLIB_StateType st,
+                                unsigned int flags)
+{
+    return tpm_iface[0]->ValidateState(st, flags);
+}
+
 static struct libtpms_callbacks libtpms_cbs;
 
 struct libtpms_callbacks *TPMLIB_GetCallbacks(void)

src/tpm_library_intern.h

@@ -65,6 +65,8 @@ struct tpm_interface {
     TPM_RESULT (*HashData)(const unsigned char *data,
                            uint32_t data_length);
     TPM_RESULT (*HashEnd)(void);
+    TPM_RESULT (*ValidateState)(enum TPMLIB_StateType st,
+                                unsigned int flags);
 };
 
 extern const struct tpm_interface TPM12Interface;

src/tpm_tpm12_interface.c

@@ -48,6 +48,8 @@
 #include "tpm_library_intern.h"
 #include "tpm12/tpm_process.h"
 #include "tpm12/tpm_startup.h"
+#include "tpm12/tpm_global.h"
+#include "tpm12/tpm_permanent.h"
 
 TPM_RESULT TPM12_MainInit(void)
 {
@@ -194,6 +196,45 @@ uint32_t TPM12_GetBufferSize(void)
     return TPM12_SetBufferSize(0, NULL, NULL);
 }
 
+TPM_RESULT TPM12_ValidateState(enum TPMLIB_StateType st,
+                               unsigned int flags)
+{
+    TPM_RESULT ret = TPM_SUCCESS;
+    tpm_state_t tpm_state;
+
+#ifdef TPM_LIBTPMS_CALLBACKS
+    struct libtpms_callbacks *cbs = TPMLIB_GetCallbacks();
+
+    if (cbs->tpm_nvram_init) {
+        ret = cbs->tpm_nvram_init();
+        if (ret != TPM_SUCCESS)
+            return ret;
+    }
+#endif
+
+    ret = TPM_Global_Init(&tpm_state);
+    tpm_state.tpm_number = 0;
+
+    if ((ret == TPM_SUCCESS) &
+        (st & TPMLIB_STATE_PERMANENT)) {
+        ret = TPM_PermanentAll_NVLoad(&tpm_state);
+    }
+
+    if ((ret == TPM_SUCCESS) &
+        (st & TPMLIB_STATE_VOLATILE)) {
+        ret = TPM_SaveState_NVLoad(&tpm_state);
+    }
+
+    if ((ret == TPM_SUCCESS) &
+        (st & TPMLIB_STATE_SAVE_STATE)) {
+        ret = TPM_VolatileAll_NVLoad(&tpm_state);
+    }
+
+    TPM_Global_Delete(&tpm_state);
+
+    return ret;
+}
+
 const struct tpm_interface TPM12Interface = {
     .MainInit = TPM12_MainInit,
     .Terminate = TPM12_Terminate,
@@ -205,4 +246,5 @@ const struct tpm_interface TPM12Interface = {
     .HashData = TPM12_IO_Hash_Data,
     .HashEnd = TPM12_IO_Hash_End,
     .SetBufferSize = TPM12_SetBufferSize,
+    .ValidateState = TPM12_ValidateState,
 };