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Re: [Xen-devel] [VTPM v7 1/8] add vtpm-stubdom code



For future reference please could you include an indication of what
changed in a new posting of a series, either in the 0/N mail (which is
useful to include as an intro in any case) or in the individual
changelogs.

On Thu, 2012-12-06 at 18:19 +0000, Matthew Fioravante wrote:
> Add the code base for vtpm-stubdom to the stubdom
> heirarchy. Makefile changes in later patch.
> 
> Signed-off-by: Matthew Fioravante <matthew.fioravante@xxxxxxxxxx>
> Acked-by: Ian Campbell <ian.campbell@xxxxxxxxxx>
> ---
>  stubdom/vtpm/Makefile    |   37 +++++
>  stubdom/vtpm/minios.cfg  |   14 ++
>  stubdom/vtpm/vtpm.c      |  404 
> ++++++++++++++++++++++++++++++++++++++++++++++
>  stubdom/vtpm/vtpm.h      |   36 +++++
>  stubdom/vtpm/vtpm_cmd.c  |  256 +++++++++++++++++++++++++++++
>  stubdom/vtpm/vtpm_cmd.h  |   31 ++++
>  stubdom/vtpm/vtpm_pcrs.c |   43 +++++
>  stubdom/vtpm/vtpm_pcrs.h |   53 ++++++
>  stubdom/vtpm/vtpmblk.c   |  307 +++++++++++++++++++++++++++++++++++
>  stubdom/vtpm/vtpmblk.h   |   31 ++++
>  10 files changed, 1212 insertions(+)
>  create mode 100644 stubdom/vtpm/Makefile
>  create mode 100644 stubdom/vtpm/minios.cfg
>  create mode 100644 stubdom/vtpm/vtpm.c
>  create mode 100644 stubdom/vtpm/vtpm.h
>  create mode 100644 stubdom/vtpm/vtpm_cmd.c
>  create mode 100644 stubdom/vtpm/vtpm_cmd.h
>  create mode 100644 stubdom/vtpm/vtpm_pcrs.c
>  create mode 100644 stubdom/vtpm/vtpm_pcrs.h
>  create mode 100644 stubdom/vtpm/vtpmblk.c
>  create mode 100644 stubdom/vtpm/vtpmblk.h
> 
> diff --git a/stubdom/vtpm/Makefile b/stubdom/vtpm/Makefile
> new file mode 100644
> index 0000000..686c0ea
> --- /dev/null
> +++ b/stubdom/vtpm/Makefile
> @@ -0,0 +1,37 @@
> +# Copyright (c) 2010-2012 United States Government, as represented by
> +# the Secretary of Defense.  All rights reserved.
> +#
> +# THIS SOFTWARE AND ITS DOCUMENTATION ARE PROVIDED AS IS AND WITHOUT
> +# ANY EXPRESS OR IMPLIED WARRANTIES WHATSOEVER. ALL WARRANTIES
> +# INCLUDING, BUT NOT LIMITED TO, PERFORMANCE, MERCHANTABILITY, FITNESS
> +# FOR A PARTICULAR  PURPOSE, AND NONINFRINGEMENT ARE HEREBY
> +# DISCLAIMED. USERS ASSUME THE ENTIRE RISK AND LIABILITY OF USING THE
> +# SOFTWARE.
> +#
> +
> +XEN_ROOT=../..
> +
> +PSSL_DIR=../polarssl-$(XEN_TARGET_ARCH)/library
> +PSSL_OBJS=aes.o sha1.o entropy.o ctr_drbg.o sha4.o
> +
> +TARGET=vtpm.a
> +OBJS=vtpm.o vtpm_cmd.o vtpmblk.o vtpm_pcrs.o
> +
> +
> +CPPFLAGS+=-I../tpm_emulator-$(XEN_TARGET_ARCH)/build
> +CPPFLAGS+=-I../tpm_emulator-$(XEN_TARGET_ARCH)/tpm
> +CPPFLAGS+=-I../tpm_emulator-$(XEN_TARGET_ARCH)/crypto
> +CPPFLAGS+=-I../tpm_emulator-$(XEN_TARGET_ARCH)
> +
> +$(TARGET): $(OBJS)
> +       ar -cr $@ $(OBJS) $(TPMEMU_OBJS) $(foreach 
> obj,$(PSSL_OBJS),$(PSSL_DIR)/$(obj))
> +
> +$(OBJS): vtpm_manager.h
> +
> +vtpm_manager.h:
> +       ln -s ../vtpmmgr/vtpm_manager.h vtpm_manager.h
> +
> +clean:
> +       -rm $(TARGET) $(OBJS) vtpm_manager.h
> +
> +.PHONY: clean
> diff --git a/stubdom/vtpm/minios.cfg b/stubdom/vtpm/minios.cfg
> new file mode 100644
> index 0000000..31652ee
> --- /dev/null
> +++ b/stubdom/vtpm/minios.cfg
> @@ -0,0 +1,14 @@
> +CONFIG_TPMFRONT=y
> +CONFIG_TPM_TIS=n
> +CONFIG_TPMBACK=y
> +CONFIG_START_NETWORK=n
> +CONFIG_TEST=n
> +CONFIG_PCIFRONT=n
> +CONFIG_BLKFRONT=y
> +CONFIG_NETFRONT=n
> +CONFIG_FBFRONT=n
> +CONFIG_KBDFRONT=n
> +CONFIG_CONSFRONT=n
> +CONFIG_XENBUS=y
> +CONFIG_LWIP=n
> +CONFIG_XC=n
> diff --git a/stubdom/vtpm/vtpm.c b/stubdom/vtpm/vtpm.c
> new file mode 100644
> index 0000000..71aef78
> --- /dev/null
> +++ b/stubdom/vtpm/vtpm.c
> @@ -0,0 +1,404 @@
> +/*
> + * Copyright (c) 2010-2012 United States Government, as represented by
> + * the Secretary of Defense.  All rights reserved.
> + *
> + * THIS SOFTWARE AND ITS DOCUMENTATION ARE PROVIDED AS IS AND WITHOUT
> + * ANY EXPRESS OR IMPLIED WARRANTIES WHATSOEVER. ALL WARRANTIES
> + * INCLUDING, BUT NOT LIMITED TO, PERFORMANCE, MERCHANTABILITY, FITNESS
> + * FOR A PARTICULAR  PURPOSE, AND NONINFRINGEMENT ARE HEREBY
> + * DISCLAIMED. USERS ASSUME THE ENTIRE RISK AND LIABILITY OF USING THE
> + * SOFTWARE.
> + */
> +
> +#include <stdio.h>
> +#include <stdint.h>
> +#include <inttypes.h>
> +#include <stdlib.h>
> +#include <unistd.h>
> +#include <string.h>
> +#include <syslog.h>
> +#include <stdbool.h>
> +#include <errno.h>
> +#include <sys/time.h>
> +#include <xen/xen.h>
> +#include <tpmback.h>
> +#include <tpmfront.h>
> +
> +#include <polarssl/entropy.h>
> +#include <polarssl/ctr_drbg.h>
> +
> +#include "tpm/tpm_emulator_extern.h"
> +#include "tpm/tpm_marshalling.h"
> +#include "vtpm.h"
> +#include "vtpm_cmd.h"
> +#include "vtpm_pcrs.h"
> +#include "vtpmblk.h"
> +
> +#define TPM_LOG_INFO LOG_INFO
> +#define TPM_LOG_ERROR LOG_ERR
> +#define TPM_LOG_DEBUG LOG_DEBUG
> +
> +/* Global commandline options - default values */
> +struct Opt_args opt_args = {
> +   .startup = ST_CLEAR,
> +   .loglevel = TPM_LOG_INFO,
> +   .hwinitpcrs = VTPM_PCRNONE,
> +   .tpmconf = 0,
> +   .enable_maint_cmds = false,
> +};
> +
> +static uint32_t badords[32];
> +static unsigned int n_badords = 0;
> +
> +entropy_context entropy;
> +ctr_drbg_context ctr_drbg;
> +
> +struct tpmfront_dev* tpmfront_dev;
> +
> +void vtpm_get_extern_random_bytes(void *buf, size_t nbytes)
> +{
> +   ctr_drbg_random(&ctr_drbg, buf, nbytes);
> +}
> +
> +int vtpm_read_from_file(uint8_t **data, size_t *data_length) {
> +   return read_vtpmblk(tpmfront_dev, data, data_length);
> +}
> +
> +int vtpm_write_to_file(uint8_t *data, size_t data_length) {
> +   return write_vtpmblk(tpmfront_dev, data, data_length);
> +}
> +
> +int vtpm_extern_init_fake(void) {
> +   return 0;
> +}
> +
> +void vtpm_extern_release_fake(void) {
> +}
> +
> +
> +void vtpm_log(int priority, const char *fmt, ...)
> +{
> +   if(opt_args.loglevel >= priority) {
> +      va_list v;
> +      va_start(v, fmt);
> +      vprintf(fmt, v);
> +      va_end(v);
> +   }
> +}
> +
> +static uint64_t vtpm_get_ticks(void)
> +{
> +  static uint64_t old_t = 0;
> +  uint64_t new_t, res_t;
> +  struct timeval tv;
> +  gettimeofday(&tv, NULL);
> +  new_t = (uint64_t)tv.tv_sec * 1000000 + (uint64_t)tv.tv_usec;
> +  res_t = (old_t > 0) ? new_t - old_t : 0;
> +  old_t = new_t;
> +  return res_t;
> +}
> +
> +
> +static int tpm_entropy_source(void* dummy, unsigned char* data, size_t len, 
> size_t* olen) {
> +   UINT32 sz = len;
> +   TPM_RESULT rc = VTPM_GetRandom(tpmfront_dev, data, &sz);
> +   *olen = sz;
> +   return rc == TPM_SUCCESS ? 0 : POLARSSL_ERR_ENTROPY_SOURCE_FAILED;
> +}
> +
> +int init_random(void) {
> +   /* Initialize the rng */
> +   entropy_init(&entropy);
> +   entropy_add_source(&entropy, tpm_entropy_source, NULL, 0);
> +   entropy_gather(&entropy);
> +   ctr_drbg_init(&ctr_drbg, entropy_func, &entropy, NULL, 0);
> +   ctr_drbg_set_prediction_resistance( &ctr_drbg, CTR_DRBG_PR_OFF );
> +
> +   return 0;
> +}
> +
> +int check_ordinal(tpmcmd_t* tpmcmd) {
> +   TPM_COMMAND_CODE ord;
> +   UINT32 len = 4;
> +   BYTE* ptr;
> +   unsigned int i;
> +
> +   if(tpmcmd->req_len < 10) {
> +      return true;
> +   }
> +
> +   ptr = tpmcmd->req + 6;
> +   tpm_unmarshal_UINT32(&ptr, &len, &ord);
> +
> +   for(i = 0; i < n_badords; ++i) {
> +      if(ord == badords[i]) {
> +         error("Disabled command ordinal (%" PRIu32") requested!\n");
> +         return false;
> +      }
> +   }
> +   return true;
> +}
> +
> +static void main_loop(void) {
> +   tpmcmd_t* tpmcmd = NULL;
> +   domid_t domid;              /* Domid of frontend */
> +   unsigned int handle;        /* handle of frontend */
> +   int res = -1;
> +
> +   info("VTPM Initializing\n");
> +
> +   /* Set required tpm config args */
> +   opt_args.tpmconf |= TPM_CONF_STRONG_PERSISTENCE;
> +   opt_args.tpmconf &= ~TPM_CONF_USE_INTERNAL_PRNG;
> +   opt_args.tpmconf |= TPM_CONF_GENERATE_EK;
> +   opt_args.tpmconf |= TPM_CONF_GENERATE_SEED_DAA;
> +
> +   /* Initialize the emulator */
> +   tpm_emulator_init(opt_args.startup, opt_args.tpmconf);
> +
> +   /* Initialize any requested PCRs with hardware TPM values */
> +   if(vtpm_initialize_hw_pcrs(tpmfront_dev, opt_args.hwinitpcrs) != 
> TPM_SUCCESS) {
> +      error("Failed to initialize PCRs with hardware TPM values");
> +      goto abort_postpcrs;
> +   }
> +
> +   /* Wait for the frontend domain to connect */
> +   info("Waiting for frontend domain to connect..");
> +   if(tpmback_wait_for_frontend_connect(&domid, &handle) == 0) {
> +      info("VTPM attached to Frontend %u/%u", (unsigned int) domid, handle);
> +   } else {
> +      error("Unable to attach to a frontend");
> +   }
> +
> +   tpmcmd = tpmback_req(domid, handle);
> +   while(tpmcmd) {
> +      /* Handle the request */
> +      if(tpmcmd->req_len) {
> +        tpmcmd->resp = NULL;
> +        tpmcmd->resp_len = 0;
> +
> +         /* First check for disabled ordinals */
> +         if(!check_ordinal(tpmcmd)) {
> +            create_error_response(tpmcmd, TPM_BAD_ORDINAL);
> +         }
> +         /* If not disabled, do the command */
> +         else {
> +            if((res = tpm_handle_command(tpmcmd->req, tpmcmd->req_len, 
> &tpmcmd->resp, &tpmcmd->resp_len)) != 0) {
> +               error("tpm_handle_command() failed");
> +               create_error_response(tpmcmd, TPM_FAIL);
> +            }
> +         }
> +      }
> +
> +      /* Send the response */
> +      tpmback_resp(tpmcmd);
> +
> +      /* Wait for the next request */
> +      tpmcmd = tpmback_req(domid, handle);
> +
> +   }
> +
> +abort_postpcrs:
> +   info("VTPM Shutting down\n");
> +
> +   tpm_emulator_shutdown();
> +}
> +
> +int parse_cmd_line(int argc, char** argv)
> +{
> +   char sval[25];
> +   char* logstr = NULL;
> +   /* Parse the command strings */
> +   for(unsigned int i = 1; i < argc; ++i) {
> +      if (sscanf(argv[i], "loglevel=%25s", sval) == 1){
> +        if (!strcmp(sval, "debug")) {
> +           opt_args.loglevel = TPM_LOG_DEBUG;
> +           logstr = "debug";
> +        }
> +        else if (!strcmp(sval, "info")) {
> +           logstr = "info";
> +           opt_args.loglevel = TPM_LOG_INFO;
> +        }
> +        else if (!strcmp(sval, "error")) {
> +           logstr = "error";
> +           opt_args.loglevel = TPM_LOG_ERROR;
> +        }
> +      }
> +      else if (!strcmp(argv[i], "clear")) {
> +        opt_args.startup = ST_CLEAR;
> +      }
> +      else if (!strcmp(argv[i], "save")) {
> +        opt_args.startup = ST_SAVE;
> +      }
> +      else if (!strcmp(argv[i], "deactivated")) {
> +        opt_args.startup = ST_DEACTIVATED;
> +      }
> +      else if (!strncmp(argv[i], "maintcmds=", 10)) {
> +         if(!strcmp(argv[i] + 10, "1")) {
> +            opt_args.enable_maint_cmds = true;
> +         } else if(!strcmp(argv[i] + 10, "0")) {
> +            opt_args.enable_maint_cmds = false;
> +         }
> +      }
> +      else if(!strncmp(argv[i], "hwinitpcr=", 10)) {
> +         char *pch = argv[i] + 10;
> +         unsigned int v1, v2;
> +         pch = strtok(pch, ",");
> +         while(pch != NULL) {
> +            if(!strcmp(pch, "all")) {
> +               //Set all
> +               opt_args.hwinitpcrs = VTPM_PCRALL;
> +            } else if(!strcmp(pch, "none")) {
> +               //Set none
> +               opt_args.hwinitpcrs = VTPM_PCRNONE;
> +            } else if(sscanf(pch, "%u", &v1) == 1) {
> +               //Set one
> +               if(v1 >= TPM_NUM_PCR) {
> +                  error("hwinitpcr error: Invalid PCR index %u", v1);
> +                  return -1;
> +               }
> +               opt_args.hwinitpcrs |= (1 << v1);
> +            } else if(sscanf(pch, "%u-%u", &v1, &v2) == 2) {
> +               //Set range
> +               if(v1 >= TPM_NUM_PCR) {
> +                  error("hwinitpcr error: Invalid PCR index %u", v1);
> +                  return -1;
> +               }
> +               if(v2 >= TPM_NUM_PCR) {
> +                  error("hwinitpcr error: Invalid PCR index %u", v1);
> +                  return -1;
> +               }
> +               if(v2 < v1) {
> +                  unsigned tp = v1;
> +                  v1 = v2;
> +                  v2 = tp;
> +               }
> +               for(unsigned int i = v1; i <= v2; ++i) {
> +                  opt_args.hwinitpcrs |= (1 << i);
> +               }
> +            } else {
> +               error("hwintipcr error: Invalid PCR specification : %s", pch);
> +               return -1;
> +            }
> +            pch = strtok(NULL, ",");
> +         }
> +      }
> +      else {
> +        error("Invalid command line option `%s'", argv[i]);
> +      }
> +
> +   }
> +
> +   /* Check Errors and print results */
> +   switch(opt_args.startup) {
> +      case ST_CLEAR:
> +        info("Startup mode is `clear'");
> +        break;
> +      case ST_SAVE:
> +        info("Startup mode is `save'");
> +        break;
> +      case ST_DEACTIVATED:
> +        info("Startup mode is `deactivated'");
> +        break;
> +      default:
> +        error("Invalid startup mode %d", opt_args.startup);
> +        return -1;
> +   }
> +
> +   if(opt_args.hwinitpcrs & (VTPM_PCRALL))
> +   {
> +      char pcrstr[1024];
> +      char* ptr = pcrstr;
> +
> +      pcrstr[0] = '\0';
> +      info("The following PCRs will be initialized with values from the 
> hardware TPM:");
> +      for(unsigned int i = 0; i < TPM_NUM_PCR; ++i) {
> +         if(opt_args.hwinitpcrs & (1 << i)) {
> +            ptr += sprintf(ptr, "%u, ", i);
> +         }
> +      }
> +      /* get rid of the last comma if any numbers were printed */
> +      *(ptr -2) = '\0';
> +
> +      info("\t%s", pcrstr);
> +   } else {
> +      info("All PCRs initialized to default values");
> +   }
> +
> +   if(!opt_args.enable_maint_cmds) {
> +      info("TPM Maintenance Commands disabled");
> +      badords[n_badords++] = TPM_ORD_CreateMaintenanceArchive;
> +      badords[n_badords++] = TPM_ORD_LoadMaintenanceArchive;
> +      badords[n_badords++] = TPM_ORD_KillMaintenanceFeature;
> +      badords[n_badords++] = TPM_ORD_LoadManuMaintPub;
> +      badords[n_badords++] = TPM_ORD_ReadManuMaintPub;
> +   } else {
> +      info("TPM Maintenance Commands enabled");
> +   }
> +
> +   info("Log level set to %s", logstr);
> +
> +   return 0;
> +}
> +
> +void cleanup_opt_args(void) {
> +}
> +
> +int main(int argc, char **argv)
> +{
> +   //FIXME: initializing blkfront without this sleep causes the domain to 
> crash on boot
> +   sleep(2);
> +
> +   /* Setup extern function pointers */
> +   tpm_extern_init = vtpm_extern_init_fake;
> +   tpm_extern_release = vtpm_extern_release_fake;
> +   tpm_malloc = malloc;
> +   tpm_free = free;
> +   tpm_log = vtpm_log;
> +   tpm_get_ticks = vtpm_get_ticks;
> +   tpm_get_extern_random_bytes = vtpm_get_extern_random_bytes;
> +   tpm_write_to_storage = vtpm_write_to_file;
> +   tpm_read_from_storage = vtpm_read_from_file;
> +
> +   info("starting TPM Emulator (1.2.%d.%d-%d)", VERSION_MAJOR, 
> VERSION_MINOR, VERSION_BUILD);
> +   if(parse_cmd_line(argc, argv)) {
> +      error("Error parsing commandline\n");
> +      return -1;
> +   }
> +
> +   /* Initialize devices */
> +   init_tpmback();
> +   if((tpmfront_dev = init_tpmfront(NULL)) == NULL) {
> +      error("Unable to initialize tpmfront device");
> +      goto abort_posttpmfront;
> +   }
> +
> +   /* Seed the RNG with entropy from hardware TPM */
> +   if(init_random()) {
> +      error("Unable to initialize RNG");
> +      goto abort_postrng;
> +   }
> +
> +   /* Initialize blkfront device */
> +   if(init_vtpmblk(tpmfront_dev)) {
> +      error("Unable to initialize Blkfront persistent storage");
> +      goto abort_postvtpmblk;
> +   }
> +
> +   /* Run main loop */
> +   main_loop();
> +
> +   /* Shutdown blkfront */
> +   shutdown_vtpmblk();
> +abort_postvtpmblk:
> +abort_postrng:
> +
> +   /* Close devices */
> +   shutdown_tpmfront(tpmfront_dev);
> +abort_posttpmfront:
> +   shutdown_tpmback();
> +
> +   cleanup_opt_args();
> +
> +   return 0;
> +}
> diff --git a/stubdom/vtpm/vtpm.h b/stubdom/vtpm/vtpm.h
> new file mode 100644
> index 0000000..5919e44
> --- /dev/null
> +++ b/stubdom/vtpm/vtpm.h
> @@ -0,0 +1,36 @@
> +/*
> + * Copyright (c) 2010-2012 United States Government, as represented by
> + * the Secretary of Defense.  All rights reserved.
> + *
> + * THIS SOFTWARE AND ITS DOCUMENTATION ARE PROVIDED AS IS AND WITHOUT
> + * ANY EXPRESS OR IMPLIED WARRANTIES WHATSOEVER. ALL WARRANTIES
> + * INCLUDING, BUT NOT LIMITED TO, PERFORMANCE, MERCHANTABILITY, FITNESS
> + * FOR A PARTICULAR  PURPOSE, AND NONINFRINGEMENT ARE HEREBY
> + * DISCLAIMED. USERS ASSUME THE ENTIRE RISK AND LIABILITY OF USING THE
> + * SOFTWARE.
> + */
> +
> +#ifndef VTPM_H
> +#define VTPM_H
> +
> +#include <stdbool.h>
> +
> +/* For testing */
> +#define VERS_CMD 
> "\x00\xC1\x00\x00\x00\x16\x00\x00\x00\x65\x00\x00\x00\x05\x00\x00\x00\x04\x00\x00\x01\x03"
> +#define VERS_CMD_LEN 22
> +
> +/* Global commandline options */
> +struct Opt_args {
> +   enum StartUp {
> +      ST_CLEAR = 1,
> +      ST_SAVE = 2,
> +      ST_DEACTIVATED = 3
> +   } startup;
> +   unsigned long hwinitpcrs;
> +   int loglevel;
> +   uint32_t tpmconf;
> +   bool enable_maint_cmds;
> +};
> +extern struct Opt_args opt_args;
> +
> +#endif
> diff --git a/stubdom/vtpm/vtpm_cmd.c b/stubdom/vtpm/vtpm_cmd.c
> new file mode 100644
> index 0000000..7eae98b
> --- /dev/null
> +++ b/stubdom/vtpm/vtpm_cmd.c
> @@ -0,0 +1,256 @@
> +/*
> + * Copyright (c) 2010-2012 United States Government, as represented by
> + * the Secretary of Defense.  All rights reserved.
> + *
> + * THIS SOFTWARE AND ITS DOCUMENTATION ARE PROVIDED AS IS AND WITHOUT
> + * ANY EXPRESS OR IMPLIED WARRANTIES WHATSOEVER. ALL WARRANTIES
> + * INCLUDING, BUT NOT LIMITED TO, PERFORMANCE, MERCHANTABILITY, FITNESS
> + * FOR A PARTICULAR  PURPOSE, AND NONINFRINGEMENT ARE HEREBY
> + * DISCLAIMED. USERS ASSUME THE ENTIRE RISK AND LIABILITY OF USING THE
> + * SOFTWARE.
> + */
> +
> +#include <types.h>
> +#include <xen/xen.h>
> +#include <mm.h>
> +#include <gnttab.h>
> +#include "tpm/tpm_marshalling.h"
> +#include "vtpm_manager.h"
> +#include "vtpm_cmd.h"
> +#include <tpmback.h>
> +
> +#define TRYFAILGOTO(C) \
> +   if((C)) { \
> +      status = TPM_FAIL; \
> +      goto abort_egress; \
> +   }
> +#define TRYFAILGOTOMSG(C, msg) \
> +   if((C)) { \
> +      status = TPM_FAIL; \
> +      error(msg); \
> +      goto abort_egress; \
> +   }
> +#define CHECKSTATUSGOTO(ret, fname) \
> +   if((ret) != TPM_SUCCESS) { \
> +      error("%s failed with error code (%lu)", fname, (unsigned long) ret); \
> +      status = ord; \
> +      goto abort_egress; \
> +   }
> +
> +#define ERR_MALFORMED "Malformed response from backend"
> +#define ERR_TPMFRONT "Error sending command through frontend device"
> +
> +struct shpage {
> +   void* page;
> +   grant_ref_t grantref;
> +};
> +
> +typedef struct shpage shpage_t;
> +
> +static inline int pack_header(uint8_t** bptr, UINT32* len, TPM_TAG tag, 
> UINT32 size, TPM_COMMAND_CODE ord)
> +{
> +   return *bptr == NULL ||
> +        tpm_marshal_UINT16(bptr, len, tag) ||
> +        tpm_marshal_UINT32(bptr, len, size) ||
> +        tpm_marshal_UINT32(bptr, len, ord);
> +}
> +
> +static inline int unpack_header(uint8_t** bptr, UINT32* len, TPM_TAG* tag, 
> UINT32* size, TPM_COMMAND_CODE* ord)
> +{
> +   return *bptr == NULL ||
> +        tpm_unmarshal_UINT16(bptr, len, tag) ||
> +        tpm_unmarshal_UINT32(bptr, len, size) ||
> +        tpm_unmarshal_UINT32(bptr, len, ord);
> +}
> +
> +int create_error_response(tpmcmd_t* tpmcmd, TPM_RESULT errorcode)
> +{
> +   TPM_TAG tag;
> +   UINT32 len = tpmcmd->req_len;
> +   uint8_t* respptr;
> +   uint8_t* cmdptr = tpmcmd->req;
> +
> +   if(!tpm_unmarshal_UINT16(&cmdptr, &len, &tag)) {
> +      switch (tag) {
> +         case TPM_TAG_RQU_COMMAND:
> +            tag = TPM_TAG_RSP_COMMAND;
> +            break;
> +         case TPM_TAG_RQU_AUTH1_COMMAND:
> +            tag = TPM_TAG_RQU_AUTH2_COMMAND;
> +            break;
> +         case TPM_TAG_RQU_AUTH2_COMMAND:
> +            tag = TPM_TAG_RQU_AUTH2_COMMAND;
> +            break;
> +      }
> +   } else {
> +      tag = TPM_TAG_RSP_COMMAND;
> +   }
> +
> +   tpmcmd->resp_len = len = 10;
> +   tpmcmd->resp = respptr = tpm_malloc(tpmcmd->resp_len);
> +
> +   return pack_header(&respptr, &len, tag, len, errorcode);
> +}
> +
> +TPM_RESULT VTPM_GetRandom(struct tpmfront_dev* tpmfront_dev, BYTE* bytes, 
> UINT32 *numbytes) {
> +   TPM_RESULT status = TPM_SUCCESS;
> +   uint8_t* cmdbuf, *resp, *bptr;
> +   size_t resplen = 0;
> +   UINT32 len;
> +
> +   /*Ask the real tpm for random bytes for the seed */
> +   TPM_TAG tag = TPM_TAG_RQU_COMMAND;
> +   UINT32 size;
> +   TPM_COMMAND_CODE ord = TPM_ORD_GetRandom;
> +   len = size = sizeof(TPM_TAG) + sizeof(UINT32) + sizeof(TPM_COMMAND_CODE) 
> + sizeof(UINT32);
> +
> +   /*Create the raw tpm command */
> +   bptr = cmdbuf = malloc(size);
> +   TRYFAILGOTO(pack_header(&bptr, &len, tag, size, ord));
> +   TRYFAILGOTO(tpm_marshal_UINT32(&bptr, &len, *numbytes));
> +
> +   /* Send cmd, wait for response */
> +   TRYFAILGOTOMSG(tpmfront_cmd(tpmfront_dev, cmdbuf, size, &resp, &resplen),
> +      ERR_TPMFRONT);
> +
> +   bptr = resp; len = resplen;
> +   TRYFAILGOTOMSG(unpack_header(&bptr, &len, &tag, &size, &ord), 
> ERR_MALFORMED);
> +
> +   //Check return status of command
> +   CHECKSTATUSGOTO(ord, "TPM_GetRandom()");
> +
> +   // Get the number of random bytes in the response
> +   TRYFAILGOTOMSG(tpm_unmarshal_UINT32(&bptr, &len, &size), ERR_MALFORMED);
> +   *numbytes = size;
> +
> +   //Get the random bytes out, tpm may give us less bytes than what we wanrt
> +   TRYFAILGOTOMSG(tpm_unmarshal_BYTE_ARRAY(&bptr, &len, bytes, *numbytes), 
> ERR_MALFORMED);
> +
> +   goto egress;
> +abort_egress:
> +egress:
> +   free(cmdbuf);
> +   return status;
> +
> +}
> +
> +TPM_RESULT VTPM_LoadHashKey(struct tpmfront_dev* tpmfront_dev, uint8_t** 
> data, size_t* data_length)
> +{
> +   TPM_RESULT status = TPM_SUCCESS;
> +   uint8_t* bptr, *resp;
> +   uint8_t* cmdbuf = NULL;
> +   size_t resplen = 0;
> +   UINT32 len;
> +
> +   TPM_TAG tag = VTPM_TAG_REQ;
> +   UINT32 size;
> +   TPM_COMMAND_CODE ord = VTPM_ORD_LOADHASHKEY;
> +
> +   /*Create the command*/
> +   len = size = VTPM_COMMAND_HEADER_SIZE;
> +   bptr = cmdbuf = malloc(size);
> +   TRYFAILGOTO(pack_header(&bptr, &len, tag, size, ord));
> +
> +   /* Send the command to vtpm_manager */
> +   info("Requesting Encryption key from backend");
> +   TRYFAILGOTOMSG(tpmfront_cmd(tpmfront_dev, cmdbuf, size, &resp, &resplen), 
> ERR_TPMFRONT);
> +
> +   /* Unpack response header */
> +   bptr = resp;
> +   len = resplen;
> +   TRYFAILGOTOMSG(unpack_header(&bptr, &len, &tag, &size, &ord), 
> ERR_MALFORMED);
> +
> +   /* Check return code */
> +   CHECKSTATUSGOTO(ord, "VTPM_LoadHashKey()");
> +
> +   /* Get the size of the key */
> +   *data_length = size - VTPM_COMMAND_HEADER_SIZE;
> +
> +   /* Copy the key bits */
> +   *data = malloc(*data_length);
> +   memcpy(*data, bptr, *data_length);
> +
> +   goto egress;
> +abort_egress:
> +   error("VTPM_LoadHashKey failed");
> +egress:
> +   free(cmdbuf);
> +   return status;
> +}
> +
> +TPM_RESULT VTPM_SaveHashKey(struct tpmfront_dev* tpmfront_dev, uint8_t* 
> data, size_t data_length)
> +{
> +   TPM_RESULT status = TPM_SUCCESS;
> +   uint8_t* bptr, *resp;
> +   uint8_t* cmdbuf = NULL;
> +   size_t resplen = 0;
> +   UINT32 len;
> +
> +   TPM_TAG tag = VTPM_TAG_REQ;
> +   UINT32 size;
> +   TPM_COMMAND_CODE ord = VTPM_ORD_SAVEHASHKEY;
> +
> +   /*Create the command*/
> +   len = size = VTPM_COMMAND_HEADER_SIZE + data_length;
> +   bptr = cmdbuf = malloc(size);
> +   TRYFAILGOTO(pack_header(&bptr, &len, tag, size, ord));
> +   memcpy(bptr, data, data_length);
> +   bptr += data_length;
> +
> +   /* Send the command to vtpm_manager */
> +   info("Sending encryption key to backend");
> +   TRYFAILGOTOMSG(tpmfront_cmd(tpmfront_dev, cmdbuf, size, &resp, &resplen), 
> ERR_TPMFRONT);
> +
> +   /* Unpack response header */
> +   bptr = resp;
> +   len = resplen;
> +   TRYFAILGOTOMSG(unpack_header(&bptr, &len, &tag, &size, &ord), 
> ERR_MALFORMED);
> +
> +   /* Check return code */
> +   CHECKSTATUSGOTO(ord, "VTPM_SaveHashKey()");
> +
> +   goto egress;
> +abort_egress:
> +   error("VTPM_SaveHashKey failed");
> +egress:
> +   free(cmdbuf);
> +   return status;
> +}
> +
> +TPM_RESULT VTPM_PCRRead(struct tpmfront_dev* tpmfront_dev, UINT32 pcrIndex, 
> BYTE* outDigest)
> +{
> +   TPM_RESULT status = TPM_SUCCESS;
> +   uint8_t *cmdbuf, *resp, *bptr;
> +   size_t resplen = 0;
> +   UINT32 len;
> +
> +   /*Just send a TPM_PCRRead Command to the HW tpm */
> +   TPM_TAG tag = TPM_TAG_RQU_COMMAND;
> +   UINT32 size;
> +   TPM_COMMAND_CODE ord = TPM_ORD_PCRRead;
> +   len = size = sizeof(TPM_TAG) + sizeof(UINT32) + sizeof(TPM_COMMAND_CODE) 
> + sizeof(UINT32);
> +
> +   /*Create the raw tpm cmd */
> +   bptr = cmdbuf = malloc(size);
> +   TRYFAILGOTO(pack_header(&bptr, &len, tag, size, ord));
> +   TRYFAILGOTO(tpm_marshal_UINT32(&bptr, &len, pcrIndex));
> +
> +   /*Send Cmd wait for response */
> +   TRYFAILGOTOMSG(tpmfront_cmd(tpmfront_dev, cmdbuf, size, &resp, &resplen), 
> ERR_TPMFRONT);
> +
> +   bptr = resp; len = resplen;
> +   TRYFAILGOTOMSG(unpack_header(&bptr, &len, &tag, &size, &ord), 
> ERR_MALFORMED);
> +
> +   //Check return status of command
> +   CHECKSTATUSGOTO(ord, "TPM_PCRRead");
> +
> +   //Get the ptr value
> +   memcpy(outDigest, bptr, sizeof(TPM_PCRVALUE));
> +
> +   goto egress;
> +abort_egress:
> +egress:
> +   free(cmdbuf);
> +   return status;
> +
> +}
> diff --git a/stubdom/vtpm/vtpm_cmd.h b/stubdom/vtpm/vtpm_cmd.h
> new file mode 100644
> index 0000000..b0bfa22
> --- /dev/null
> +++ b/stubdom/vtpm/vtpm_cmd.h
> @@ -0,0 +1,31 @@
> +/*
> + * Copyright (c) 2010-2012 United States Government, as represented by
> + * the Secretary of Defense.  All rights reserved.
> + *
> + * THIS SOFTWARE AND ITS DOCUMENTATION ARE PROVIDED AS IS AND WITHOUT
> + * ANY EXPRESS OR IMPLIED WARRANTIES WHATSOEVER. ALL WARRANTIES
> + * INCLUDING, BUT NOT LIMITED TO, PERFORMANCE, MERCHANTABILITY, FITNESS
> + * FOR A PARTICULAR  PURPOSE, AND NONINFRINGEMENT ARE HEREBY
> + * DISCLAIMED. USERS ASSUME THE ENTIRE RISK AND LIABILITY OF USING THE
> + * SOFTWARE.
> + */
> +
> +#ifndef MANAGER_H
> +#define MANAGER_H
> +
> +#include <tpmfront.h>
> +#include <tpmback.h>
> +#include "tpm/tpm_structures.h"
> +
> +/* Create a command response error header */
> +int create_error_response(tpmcmd_t* tpmcmd, TPM_RESULT errorcode);
> +/* Request random bytes from hardware tpm, returns 0 on success */
> +TPM_RESULT VTPM_GetRandom(struct tpmfront_dev* tpmfront_dev, BYTE* bytes, 
> UINT32* numbytes);
> +/* Retreive 256 bit AES encryption key from manager */
> +TPM_RESULT VTPM_LoadHashKey(struct tpmfront_dev* tpmfront_dev, uint8_t** 
> data, size_t* data_length);
> +/* Manager securely saves our 256 bit AES encryption key */
> +TPM_RESULT VTPM_SaveHashKey(struct tpmfront_dev* tpmfront_dev, uint8_t* 
> data, size_t data_length);
> +/* Send a TPM_PCRRead command passthrough the manager to the hw tpm */
> +TPM_RESULT VTPM_PCRRead(struct tpmfront_dev* tpmfront_dev, UINT32 pcrIndex, 
> BYTE* outDigest);
> +
> +#endif
> diff --git a/stubdom/vtpm/vtpm_pcrs.c b/stubdom/vtpm/vtpm_pcrs.c
> new file mode 100644
> index 0000000..22a6cef
> --- /dev/null
> +++ b/stubdom/vtpm/vtpm_pcrs.c
> @@ -0,0 +1,43 @@
> +/*
> + * Copyright (c) 2010-2012 United States Government, as represented by
> + * the Secretary of Defense.  All rights reserved.
> + *
> + * THIS SOFTWARE AND ITS DOCUMENTATION ARE PROVIDED AS IS AND WITHOUT
> + * ANY EXPRESS OR IMPLIED WARRANTIES WHATSOEVER. ALL WARRANTIES
> + * INCLUDING, BUT NOT LIMITED TO, PERFORMANCE, MERCHANTABILITY, FITNESS
> + * FOR A PARTICULAR  PURPOSE, AND NONINFRINGEMENT ARE HEREBY
> + * DISCLAIMED. USERS ASSUME THE ENTIRE RISK AND LIABILITY OF USING THE
> + * SOFTWARE.
> + */
> +
> +#include "vtpm_pcrs.h"
> +#include "vtpm_cmd.h"
> +#include "tpm/tpm_data.h"
> +
> +#define PCR_VALUE      tpmData.permanent.data.pcrValue
> +
> +static int write_pcr_direct(unsigned int pcrIndex, uint8_t* val) {
> +   if(pcrIndex > TPM_NUM_PCR) {
> +      return TPM_BADINDEX;
> +   }
> +   memcpy(&PCR_VALUE[pcrIndex], val, sizeof(TPM_PCRVALUE));
> +   return TPM_SUCCESS;
> +}
> +
> +TPM_RESULT vtpm_initialize_hw_pcrs(struct tpmfront_dev* tpmfront_dev, 
> unsigned long pcrs)
> +{
> +   TPM_RESULT rc = TPM_SUCCESS;
> +   uint8_t digest[sizeof(TPM_PCRVALUE)];
> +
> +   for(unsigned int i = 0; i < TPM_NUM_PCR; ++i) {
> +      if(pcrs & 1 << i) {
> +         if((rc = VTPM_PCRRead(tpmfront_dev, i, digest)) != TPM_SUCCESS) {
> +            error("TPM_PCRRead failed with error : %d", rc);
> +            return rc;
> +         }
> +         write_pcr_direct(i, digest);
> +      }
> +   }
> +
> +   return rc;
> +}
> diff --git a/stubdom/vtpm/vtpm_pcrs.h b/stubdom/vtpm/vtpm_pcrs.h
> new file mode 100644
> index 0000000..11835f9
> --- /dev/null
> +++ b/stubdom/vtpm/vtpm_pcrs.h
> @@ -0,0 +1,53 @@
> +/*
> + * Copyright (c) 2010-2012 United States Government, as represented by
> + * the Secretary of Defense.  All rights reserved.
> + *
> + * THIS SOFTWARE AND ITS DOCUMENTATION ARE PROVIDED AS IS AND WITHOUT
> + * ANY EXPRESS OR IMPLIED WARRANTIES WHATSOEVER. ALL WARRANTIES
> + * INCLUDING, BUT NOT LIMITED TO, PERFORMANCE, MERCHANTABILITY, FITNESS
> + * FOR A PARTICULAR  PURPOSE, AND NONINFRINGEMENT ARE HEREBY
> + * DISCLAIMED. USERS ASSUME THE ENTIRE RISK AND LIABILITY OF USING THE
> + * SOFTWARE.
> + */
> +
> +#ifndef VTPM_PCRS_H
> +#define VTPM_PCRS_H
> +
> +#include "tpm/tpm_structures.h"
> +
> +#define VTPM_PCR0 1
> +#define VTPM_PCR1 1 << 1
> +#define VTPM_PCR2 1 << 2
> +#define VTPM_PCR3 1 << 3
> +#define VTPM_PCR4 1 << 4
> +#define VTPM_PCR5 1 << 5
> +#define VTPM_PCR6 1 << 6
> +#define VTPM_PCR7 1 << 7
> +#define VTPM_PCR8 1 << 8
> +#define VTPM_PCR9 1 << 9
> +#define VTPM_PCR10 1 << 10
> +#define VTPM_PCR11 1 << 11
> +#define VTPM_PCR12 1 << 12
> +#define VTPM_PCR13 1 << 13
> +#define VTPM_PCR14 1 << 14
> +#define VTPM_PCR15 1 << 15
> +#define VTPM_PCR16 1 << 16
> +#define VTPM_PCR17 1 << 17
> +#define VTPM_PCR18 1 << 18
> +#define VTPM_PCR19 1 << 19
> +#define VTPM_PCR20 1 << 20
> +#define VTPM_PCR21 1 << 21
> +#define VTPM_PCR22 1 << 22
> +#define VTPM_PCR23 1 << 23
> +
> +#define VTPM_PCRALL (1 << TPM_NUM_PCR) - 1
> +#define VTPM_PCRNONE 0
> +
> +#define VTPM_NUMPCRS 24
> +
> +struct tpmfront_dev;
> +
> +TPM_RESULT vtpm_initialize_hw_pcrs(struct tpmfront_dev* tpmfront_dev, 
> unsigned long pcrs);
> +
> +
> +#endif
> diff --git a/stubdom/vtpm/vtpmblk.c b/stubdom/vtpm/vtpmblk.c
> new file mode 100644
> index 0000000..b343bd8
> --- /dev/null
> +++ b/stubdom/vtpm/vtpmblk.c
> @@ -0,0 +1,307 @@
> +/*
> + * Copyright (c) 2010-2012 United States Government, as represented by
> + * the Secretary of Defense.  All rights reserved.
> + *
> + * THIS SOFTWARE AND ITS DOCUMENTATION ARE PROVIDED AS IS AND WITHOUT
> + * ANY EXPRESS OR IMPLIED WARRANTIES WHATSOEVER. ALL WARRANTIES
> + * INCLUDING, BUT NOT LIMITED TO, PERFORMANCE, MERCHANTABILITY, FITNESS
> + * FOR A PARTICULAR  PURPOSE, AND NONINFRINGEMENT ARE HEREBY
> + * DISCLAIMED. USERS ASSUME THE ENTIRE RISK AND LIABILITY OF USING THE
> + * SOFTWARE.
> + */
> +
> +#include <mini-os/byteorder.h>
> +#include "vtpmblk.h"
> +#include "tpm/tpm_marshalling.h"
> +#include "vtpm_cmd.h"
> +#include "polarssl/aes.h"
> +#include "polarssl/sha1.h"
> +#include <blkfront.h>
> +#include <unistd.h>
> +#include <errno.h>
> +#include <fcntl.h>
> +
> +/*Encryption key and block sizes */
> +#define BLKSZ 16
> +
> +static struct blkfront_dev* blkdev = NULL;
> +static int blkfront_fd = -1;
> +
> +int init_vtpmblk(struct tpmfront_dev* tpmfront_dev)
> +{
> +   struct blkfront_info blkinfo;
> +   info("Initializing persistent NVM storage\n");
> +
> +   if((blkdev = init_blkfront(NULL, &blkinfo)) == NULL) {
> +      error("BLKIO: ERROR Unable to initialize blkfront");
> +      return -1;
> +   }
> +   if (blkinfo.info & VDISK_READONLY || blkinfo.mode != O_RDWR) {
> +      error("BLKIO: ERROR block device is read only!");
> +      goto error;
> +   }
> +   if((blkfront_fd = blkfront_open(blkdev)) == -1) {
> +      error("Unable to open blkfront file descriptor!");
> +      goto error;
> +   }
> +
> +   return 0;
> +error:
> +   shutdown_blkfront(blkdev);
> +   blkdev = NULL;
> +   return -1;
> +}
> +
> +void shutdown_vtpmblk(void)
> +{
> +   close(blkfront_fd);
> +   blkfront_fd = -1;
> +   blkdev = NULL;
> +}
> +
> +int write_vtpmblk_raw(uint8_t *data, size_t data_length)
> +{
> +   int rc;
> +   uint32_t lenbuf;
> +   debug("Begin Write data=%p len=%u", data, data_length);
> +
> +   lenbuf = cpu_to_be32((uint32_t)data_length);
> +
> +   lseek(blkfront_fd, 0, SEEK_SET);
> +   if((rc = write(blkfront_fd, (uint8_t*)&lenbuf, 4)) != 4) {
> +      error("write(length) failed! error was %s", strerror(errno));
> +      return -1;
> +   }
> +   if((rc = write(blkfront_fd, data, data_length)) != data_length) {
> +      error("write(data) failed! error was %s", strerror(errno));
> +      return -1;
> +   }
> +
> +   info("Wrote %u bytes to NVM persistent storage", data_length);
> +
> +   return 0;
> +}
> +
> +int read_vtpmblk_raw(uint8_t **data, size_t *data_length)
> +{
> +   int rc;
> +   uint32_t lenbuf;
> +
> +   lseek(blkfront_fd, 0, SEEK_SET);
> +   if(( rc = read(blkfront_fd, (uint8_t*)&lenbuf, 4)) != 4) {
> +      error("read(length) failed! error was %s", strerror(errno));
> +      return -1;
> +   }
> +   *data_length = (size_t) cpu_to_be32(lenbuf);
> +   if(*data_length == 0) {
> +      error("read 0 data_length for NVM");
> +      return -1;
> +   }
> +
> +   *data = tpm_malloc(*data_length);
> +   if((rc = read(blkfront_fd, *data, *data_length)) != *data_length) {
> +      error("read(data) failed! error was %s", strerror(errno));
> +      return -1;
> +   }
> +
> +   info("Read %u bytes from NVM persistent storage", *data_length);
> +   return 0;
> +}
> +
> +int encrypt_vtpmblk(uint8_t* clear, size_t clear_len, uint8_t** cipher, 
> size_t* cipher_len, uint8_t* symkey)
> +{
> +   int rc = 0;
> +   uint8_t iv[BLKSZ];
> +   aes_context aes_ctx;
> +   UINT32 temp;
> +   int mod;
> +
> +   uint8_t* clbuf = NULL;
> +
> +   uint8_t* ivptr;
> +   int ivlen;
> +
> +   uint8_t* cptr;      //Cipher block pointer
> +   int clen;   //Cipher block length
> +
> +   /*Create a new 256 bit encryption key */
> +   if(symkey == NULL) {
> +      rc = -1;
> +      goto abort_egress;
> +   }
> +   tpm_get_extern_random_bytes(symkey, NVMKEYSZ);
> +
> +   /*Setup initialization vector - random bits and then 4 bytes clear text 
> size at the end*/
> +   temp = sizeof(UINT32);
> +   ivlen = BLKSZ - temp;
> +   tpm_get_extern_random_bytes(iv, ivlen);
> +   ivptr = iv + ivlen;
> +   tpm_marshal_UINT32(&ivptr, &temp, (UINT32) clear_len);
> +
> +   /*The clear text needs to be padded out to a multiple of BLKSZ */
> +   mod = clear_len % BLKSZ;
> +   clen = mod ? clear_len + BLKSZ - mod : clear_len;
> +   clbuf = malloc(clen);
> +   if (clbuf == NULL) {
> +      rc = -1;
> +      goto abort_egress;
> +   }
> +   memcpy(clbuf, clear, clear_len);
> +   /* zero out the padding bits - FIXME: better / more secure way to handle 
> these? */
> +   if(clen - clear_len) {
> +      memset(clbuf + clear_len, 0, clen - clear_len);
> +   }
> +
> +   /* Setup the ciphertext buffer */
> +   *cipher_len = BLKSZ + clen;         /*iv + ciphertext */
> +   cptr = *cipher = malloc(*cipher_len);
> +   if (*cipher == NULL) {
> +      rc = -1;
> +      goto abort_egress;
> +   }
> +
> +   /* Copy the IV to cipher text blob*/
> +   memcpy(cptr, iv, BLKSZ);
> +   cptr += BLKSZ;
> +
> +   /* Setup encryption */
> +   aes_setkey_enc(&aes_ctx, symkey, 256);
> +
> +   /* Do encryption now */
> +   aes_crypt_cbc(&aes_ctx, AES_ENCRYPT, clen, iv, clbuf, cptr);
> +
> +   goto egress;
> +abort_egress:
> +egress:
> +   free(clbuf);
> +   return rc;
> +}
> +int decrypt_vtpmblk(uint8_t* cipher, size_t cipher_len, uint8_t** clear, 
> size_t* clear_len, uint8_t* symkey)
> +{
> +   int rc = 0;
> +   uint8_t iv[BLKSZ];
> +   uint8_t* ivptr;
> +   UINT32 u32, temp;
> +   aes_context aes_ctx;
> +
> +   uint8_t* cptr = cipher;     //cipher block pointer
> +   int clen = cipher_len;      //cipher block length
> +
> +   /* Pull out the initialization vector */
> +   memcpy(iv, cipher, BLKSZ);
> +   cptr += BLKSZ;
> +   clen -= BLKSZ;
> +
> +   /* Setup the clear text buffer */
> +   if((*clear = malloc(clen)) == NULL) {
> +      rc = -1;
> +      goto abort_egress;
> +   }
> +
> +   /* Get the length of clear text from last 4 bytes of iv */
> +   temp = sizeof(UINT32);
> +   ivptr = iv + BLKSZ - temp;
> +   tpm_unmarshal_UINT32(&ivptr, &temp, &u32);
> +   *clear_len = u32;
> +
> +   /* Setup decryption */
> +   aes_setkey_dec(&aes_ctx, symkey, 256);
> +
> +   /* Do decryption now */
> +   if ((clen % BLKSZ) != 0) {
> +      error("Decryption Error: Cipher block size was not a multiple of %u", 
> BLKSZ);
> +      rc = -1;
> +      goto abort_egress;
> +   }
> +   aes_crypt_cbc(&aes_ctx, AES_DECRYPT, clen, iv, cptr, *clear);
> +
> +   goto egress;
> +abort_egress:
> +egress:
> +   return rc;
> +}
> +
> +int write_vtpmblk(struct tpmfront_dev* tpmfront_dev, uint8_t* data, size_t 
> data_length) {
> +   int rc;
> +   uint8_t* cipher = NULL;
> +   size_t cipher_len = 0;
> +   uint8_t hashkey[HASHKEYSZ];
> +   uint8_t* symkey = hashkey + HASHSZ;
> +
> +   /* Encrypt the data */
> +   if((rc = encrypt_vtpmblk(data, data_length, &cipher, &cipher_len, 
> symkey))) {
> +      goto abort_egress;
> +   }
> +   /* Write to disk */
> +   if((rc = write_vtpmblk_raw(cipher, cipher_len))) {
> +      goto abort_egress;
> +   }
> +   /* Get sha1 hash of data */
> +   sha1(cipher, cipher_len, hashkey);
> +
> +   /* Send hash and key to manager */
> +   if((rc = VTPM_SaveHashKey(tpmfront_dev, hashkey, HASHKEYSZ)) != 
> TPM_SUCCESS) {
> +      goto abort_egress;
> +   }
> +   goto egress;
> +abort_egress:
> +egress:
> +   free(cipher);
> +   return rc;
> +}
> +
> +int read_vtpmblk(struct tpmfront_dev* tpmfront_dev, uint8_t** data, size_t 
> *data_length) {
> +   int rc;
> +   uint8_t* cipher = NULL;
> +   size_t cipher_len = 0;
> +   size_t keysize;
> +   uint8_t* hashkey = NULL;
> +   uint8_t hash[HASHSZ];
> +   uint8_t* symkey;
> +
> +   /* Retreive the hash and the key from the manager */
> +   if((rc = VTPM_LoadHashKey(tpmfront_dev, &hashkey, &keysize)) != 
> TPM_SUCCESS) {
> +      goto abort_egress;
> +   }
> +   if(keysize != HASHKEYSZ) {
> +      error("Manager returned a hashkey of invalid size! expected %d, actual 
> %d", NVMKEYSZ, keysize);
> +      rc = -1;
> +      goto abort_egress;
> +   }
> +   symkey = hashkey + HASHSZ;
> +
> +   /* Read from disk now */
> +   if((rc = read_vtpmblk_raw(&cipher, &cipher_len))) {
> +      goto abort_egress;
> +   }
> +
> +   /* Compute the hash of the cipher text and compare */
> +   sha1(cipher, cipher_len, hash);
> +   if(memcmp(hash, hashkey, HASHSZ)) {
> +      int i;
> +      error("NVM Storage Checksum failed!");
> +      printf("Expected: ");
> +      for(i = 0; i < HASHSZ; ++i) {
> +        printf("%02hhX ", hashkey[i]);
> +      }
> +      printf("\n");
> +      printf("Actual:   ");
> +      for(i = 0; i < HASHSZ; ++i) {
> +        printf("%02hhX ", hash[i]);
> +      }
> +      printf("\n");
> +      rc = -1;
> +      goto abort_egress;
> +   }
> +
> +   /* Decrypt the blob */
> +   if((rc = decrypt_vtpmblk(cipher, cipher_len, data, data_length, symkey))) 
> {
> +      goto abort_egress;
> +   }
> +   goto egress;
> +abort_egress:
> +egress:
> +   free(cipher);
> +   free(hashkey);
> +   return rc;
> +}
> diff --git a/stubdom/vtpm/vtpmblk.h b/stubdom/vtpm/vtpmblk.h
> new file mode 100644
> index 0000000..282ce6a
> --- /dev/null
> +++ b/stubdom/vtpm/vtpmblk.h
> @@ -0,0 +1,31 @@
> +/*
> + * Copyright (c) 2010-2012 United States Government, as represented by
> + * the Secretary of Defense.  All rights reserved.
> + *
> + * THIS SOFTWARE AND ITS DOCUMENTATION ARE PROVIDED AS IS AND WITHOUT
> + * ANY EXPRESS OR IMPLIED WARRANTIES WHATSOEVER. ALL WARRANTIES
> + * INCLUDING, BUT NOT LIMITED TO, PERFORMANCE, MERCHANTABILITY, FITNESS
> + * FOR A PARTICULAR  PURPOSE, AND NONINFRINGEMENT ARE HEREBY
> + * DISCLAIMED. USERS ASSUME THE ENTIRE RISK AND LIABILITY OF USING THE
> + * SOFTWARE.
> + */
> +
> +#ifndef NVM_H
> +#define NVM_H
> +#include <mini-os/types.h>
> +#include <xen/xen.h>
> +#include <tpmfront.h>
> +
> +#define NVMKEYSZ 32
> +#define HASHSZ 20
> +#define HASHKEYSZ (NVMKEYSZ + HASHSZ)
> +
> +int init_vtpmblk(struct tpmfront_dev* tpmfront_dev);
> +void shutdown_vtpmblk(void);
> +
> +/* Encrypts and writes data to blk device */
> +int write_vtpmblk(struct tpmfront_dev* tpmfront_dev, uint8_t *data, size_t 
> data_length);
> +/* Reads, Decrypts, and returns data from blk device */
> +int read_vtpmblk(struct tpmfront_dev* tpmfront_dev, uint8_t **data, size_t 
> *data_length);
> +
> +#endif
> --
> 1.7.10.4
> 



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