diff options
Diffstat (limited to 'stubdom/vtpm/vtpm_cmd.c')
| -rw-r--r-- | stubdom/vtpm/vtpm_cmd.c | 256 |
1 files changed, 256 insertions, 0 deletions
diff --git a/stubdom/vtpm/vtpm_cmd.c b/stubdom/vtpm/vtpm_cmd.c new file mode 100644 index 0000000000..7eae98b54a --- /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; + +} |