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Diffstat (limited to 'src/tpm2/CommandAudit.c')
| -rw-r--r-- | src/tpm2/CommandAudit.c | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/src/tpm2/CommandAudit.c b/src/tpm2/CommandAudit.c new file mode 100644 index 0000000..1358c98 --- /dev/null +++ b/src/tpm2/CommandAudit.c @@ -0,0 +1,262 @@ +/********************************************************************************/ +/* */ +/* Functions That Support Command Audit */ +/* Written by Ken Goldman */ +/* IBM Thomas J. Watson Research Center */ +/* $Id: CommandAudit.c 1519 2019-11-15 20:43:51Z kgoldman $ */ +/* */ +/* Licenses and Notices */ +/* */ +/* 1. Copyright Licenses: */ +/* */ +/* - Trusted Computing Group (TCG) grants to the user of the source code in */ +/* this specification (the "Source Code") a worldwide, irrevocable, */ +/* nonexclusive, royalty free, copyright license to reproduce, create */ +/* derivative works, distribute, display and perform the Source Code and */ +/* derivative works thereof, and to grant others the rights granted herein. */ +/* */ +/* - The TCG grants to the user of the other parts of the specification */ +/* (other than the Source Code) the rights to reproduce, distribute, */ +/* display, and perform the specification solely for the purpose of */ +/* developing products based on such documents. */ +/* */ +/* 2. Source Code Distribution Conditions: */ +/* */ +/* - Redistributions of Source Code must retain the above copyright licenses, */ +/* this list of conditions and the following disclaimers. */ +/* */ +/* - Redistributions in binary form must reproduce the above copyright */ +/* licenses, this list of conditions and the following disclaimers in the */ +/* documentation and/or other materials provided with the distribution. */ +/* */ +/* 3. Disclaimers: */ +/* */ +/* - THE COPYRIGHT LICENSES SET FORTH ABOVE DO NOT REPRESENT ANY FORM OF */ +/* LICENSE OR WAIVER, EXPRESS OR IMPLIED, BY ESTOPPEL OR OTHERWISE, WITH */ +/* RESPECT TO PATENT RIGHTS HELD BY TCG MEMBERS (OR OTHER THIRD PARTIES) */ +/* THAT MAY BE NECESSARY TO IMPLEMENT THIS SPECIFICATION OR OTHERWISE. */ +/* Contact TCG Administration (admin@trustedcomputinggroup.org) for */ +/* information on specification licensing rights available through TCG */ +/* membership agreements. */ +/* */ +/* - THIS SPECIFICATION IS PROVIDED "AS IS" WITH NO EXPRESS OR IMPLIED */ +/* WARRANTIES WHATSOEVER, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR */ +/* FITNESS FOR A PARTICULAR PURPOSE, ACCURACY, COMPLETENESS, OR */ +/* NONINFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS, OR ANY WARRANTY */ +/* OTHERWISE ARISING OUT OF ANY PROPOSAL, SPECIFICATION OR SAMPLE. */ +/* */ +/* - Without limitation, TCG and its members and licensors disclaim all */ +/* liability, including liability for infringement of any proprietary */ +/* rights, relating to use of information in this specification and to the */ +/* implementation of this specification, and TCG disclaims all liability for */ +/* cost of procurement of substitute goods or services, lost profits, loss */ +/* of use, loss of data or any incidental, consequential, direct, indirect, */ +/* or special damages, whether under contract, tort, warranty or otherwise, */ +/* arising in any way out of use or reliance upon this specification or any */ +/* information herein. */ +/* */ +/* (c) Copyright IBM Corp. and others, 2016 - 2019 */ +/* */ +/********************************************************************************/ + +/* 8.1 CommandAudit.c */ +/* 8.1.1 Introduction */ +/* This file contains the functions that support command audit. */ +/* 8.1.2 Includes */ +#include "Tpm.h" +/* 8.1.3 Functions */ +/* 8.1.3.1 CommandAuditPreInstall_Init() */ +/* This function initializes the command audit list. This function simulates the behavior of + manufacturing. A function is used instead of a structure definition because this is easier than + figuring out the initialization value for a bit array. */ +/* This function would not be implemented outside of a manufacturing or simulation environment. */ +void +CommandAuditPreInstall_Init( + void + ) +{ + // Clear all the audit commands + MemorySet(gp.auditCommands, 0x00, sizeof(gp.auditCommands)); + // TPM_CC_SetCommandCodeAuditStatus always being audited + CommandAuditSet(TPM_CC_SetCommandCodeAuditStatus); + // Set initial command audit hash algorithm to be context integrity hash + // algorithm + gp.auditHashAlg = CONTEXT_INTEGRITY_HASH_ALG; + // Set up audit counter to be 0 + gp.auditCounter = 0; + // Write command audit persistent data to NV + NV_SYNC_PERSISTENT(auditCommands); + NV_SYNC_PERSISTENT(auditHashAlg); + NV_SYNC_PERSISTENT(auditCounter); + return; +} +/* 8.1.3.2 CommandAuditStartup() */ +/* This function clears the command audit digest on a TPM Reset. */ +BOOL +CommandAuditStartup( + STARTUP_TYPE type // IN: start up type + ) +{ + if((type != SU_RESTART) && (type != SU_RESUME)) + { + // Reset the digest size to initialize the digest + gr.commandAuditDigest.t.size = 0; + } + return TRUE; +} +/* 8.1.3.3 CommandAuditSet() */ +/* This function will SET the audit flag for a command. This function will not SET the audit flag + for a command that is not implemented. This ensures that the audit status is not SET when + TPM2_GetCapability() is used to read the list of audited commands. */ +/* This function is only used by TPM2_SetCommandCodeAuditStatus(). */ +/* The actions in TPM2_SetCommandCodeAuditStatus() are expected to cause the changes to be saved to + NV after it is setting and clearing bits. */ +/* Return Values Meaning */ +/* TRUE the command code audit status was changed */ +/* FALSE the command code audit status was not changed */ +BOOL +CommandAuditSet( + TPM_CC commandCode // IN: command code + ) +{ + COMMAND_INDEX commandIndex = CommandCodeToCommandIndex(commandCode); + // Only SET a bit if the corresponding command is implemented + if(commandIndex != UNIMPLEMENTED_COMMAND_INDEX) + { + // Can't audit shutdown + if(commandCode != TPM_CC_Shutdown) + { + if(!TEST_BIT(commandIndex, gp.auditCommands)) + { + // Set bit + SET_BIT(commandIndex, gp.auditCommands); + return TRUE; + } + } + } + // No change + return FALSE; +} +/* 8.1.3.4 CommandAuditClear() */ +/* This function will CLEAR the audit flag for a command. It will not CLEAR the audit flag for + TPM_CC_SetCommandCodeAuditStatus(). */ +/* This function is only used by TPM2_SetCommandCodeAuditStatus(). */ +/* The actions in TPM2_SetCommandCodeAuditStatus() are expected to cause the changes to be saved to + NV after it is setting and clearing bits. */ +/* Return Values Meaning */ +/* TRUE the command code audit status was changed */ +/* FALSE the command code audit status was not changed */ +BOOL +CommandAuditClear( + TPM_CC commandCode // IN: command code + ) +{ + COMMAND_INDEX commandIndex = CommandCodeToCommandIndex(commandCode); + // Do nothing if the command is not implemented + if(commandIndex != UNIMPLEMENTED_COMMAND_INDEX) + { + // The bit associated with TPM_CC_SetCommandCodeAuditStatus() cannot be + // cleared + if(commandCode != TPM_CC_SetCommandCodeAuditStatus) + { + if(TEST_BIT(commandIndex, gp.auditCommands)) + { + // Clear bit + CLEAR_BIT(commandIndex, gp.auditCommands); + return TRUE; + } + } + } + // No change + return FALSE; +} +/* 8.1.3.5 CommandAuditIsRequired() */ +/* This function indicates if the audit flag is SET for a command. */ +/* Return Values Meaning */ +/* TRUE if command is audited */ +/* FALSE if command is not audited */ +BOOL +CommandAuditIsRequired( + COMMAND_INDEX commandIndex // IN: command index + ) +{ + // Check the bit map. If the bit is SET, command audit is required + return(TEST_BIT(commandIndex, gp.auditCommands)); +} +/* 8.1.3.6 CommandAuditCapGetCCList() */ +/* This function returns a list of commands that have their audit bit SET. */ +/* The list starts at the input commandCode. */ +/* Return Values Meaning */ +/* YES if there are more command code available */ +/* NO all the available command code has been returned */ +TPMI_YES_NO +CommandAuditCapGetCCList( + TPM_CC commandCode, // IN: start command code + UINT32 count, // IN: count of returned TPM_CC + TPML_CC *commandList // OUT: list of TPM_CC + ) +{ + TPMI_YES_NO more = NO; + COMMAND_INDEX commandIndex; + // Initialize output handle list + commandList->count = 0; + // The maximum count of command we may return is MAX_CAP_CC + if(count > MAX_CAP_CC) count = MAX_CAP_CC; + // Find the implemented command that has a command code that is the same or + // higher than the input + // Collect audit commands + for(commandIndex = GetClosestCommandIndex(commandCode); + commandIndex != UNIMPLEMENTED_COMMAND_INDEX; + commandIndex = GetNextCommandIndex(commandIndex)) + { + if(CommandAuditIsRequired(commandIndex)) + { + if(commandList->count < count) + { + // If we have not filled up the return list, add this command + // code to its + TPM_CC cc = GET_ATTRIBUTE(s_ccAttr[commandIndex], + TPMA_CC, commandIndex); + if(IS_ATTRIBUTE(s_ccAttr[commandIndex], TPMA_CC, V)) + cc += (1 << 29); + commandList->commandCodes[commandList->count] = cc; + commandList->count++; + } + else + { + // If the return list is full but we still have command + // available, report this and stop iterating + more = YES; + break; + } + } + } + return more; +} +/* 8.1.3.7 CommandAuditGetDigest */ +/* This command is used to create a digest of the commands being audited. The commands are processed + in ascending numeric order with a list of TPM_CC being added to a hash. This operates as if all + the audited command codes were concatenated and then hashed. */ +void +CommandAuditGetDigest( + TPM2B_DIGEST *digest // OUT: command digest + ) +{ + TPM_CC commandCode; + COMMAND_INDEX commandIndex; + HASH_STATE hashState; + // Start hash + digest->t.size = CryptHashStart(&hashState, gp.auditHashAlg); + // Add command code + for(commandIndex = 0; commandIndex < COMMAND_COUNT; commandIndex++) + { + if(CommandAuditIsRequired(commandIndex)) + { + commandCode = GetCommandCode(commandIndex); + CryptDigestUpdateInt(&hashState, sizeof(commandCode), commandCode); + } + } + // Complete hash + CryptHashEnd2B(&hashState, &digest->b); + return; +} |