Vadim Bendebury | 5679752 | 2015-05-20 10:32:25 -0700 | [diff] [blame] | 1 | // This file was extracted from the TCG Published |
| 2 | // Trusted Platform Module Library |
| 3 | // Part 3: Commands |
| 4 | // Family "2.0" |
| 5 | // Level 00 Revision 01.16 |
| 6 | // October 30, 2014 |
| 7 | |
| 8 | #include "InternalRoutines.h" |
| 9 | #include "PolicyTicket_fp.h" |
| 10 | #include "Policy_spt_fp.h" |
| 11 | // |
| 12 | // |
| 13 | // Error Returns Meaning |
| 14 | // |
| 15 | // TPM_RC_CPHASH policy's cpHash was previously set to a different value |
| 16 | // TPM_RC_EXPIRED timeout value in the ticket is in the past and the ticket has expired |
| 17 | // TPM_RC_SIZE timeout or cpHash has invalid size for the |
| 18 | // TPM_RC_TICKET ticket is not valid |
| 19 | // |
| 20 | TPM_RC |
| 21 | TPM2_PolicyTicket( |
| 22 | PolicyTicket_In *in // IN: input parameter list |
| 23 | ) |
| 24 | { |
| 25 | TPM_RC result; |
| 26 | SESSION *session; |
| 27 | UINT64 timeout; |
| 28 | TPMT_TK_AUTH ticketToCompare; |
| 29 | TPM_CC commandCode = TPM_CC_PolicySecret; |
| 30 | |
| 31 | // Input Validation |
| 32 | |
| 33 | // Get pointer to the session structure |
| 34 | session = SessionGet(in->policySession); |
| 35 | |
| 36 | // NOTE: A trial policy session is not allowed to use this command. |
| 37 | // A ticket is used in place of a previously given authorization. Since |
| 38 | // a trial policy doesn't actually authenticate, the validated |
| 39 | // ticket is not necessary and, in place of using a ticket, one |
| 40 | // should use the intended authorization for which the ticket |
| 41 | // would be a substitute. |
| 42 | if(session->attributes.isTrialPolicy) |
| 43 | return TPM_RCS_ATTRIBUTES + RC_PolicyTicket_policySession; |
| 44 | |
| 45 | // Restore timeout data. The format of timeout buffer is TPM-specific. |
| 46 | // In this implementation, we simply copy the value of timeout to the |
| 47 | // buffer. |
| 48 | if(in->timeout.t.size != sizeof(UINT64)) |
| 49 | return TPM_RC_SIZE + RC_PolicyTicket_timeout; |
| 50 | timeout = BYTE_ARRAY_TO_UINT64(in->timeout.t.buffer); |
| 51 | |
| 52 | // Do the normal checks on the cpHashA and timeout values |
| 53 | result = PolicyParameterChecks(session, timeout, |
| 54 | &in->cpHashA, NULL, |
| 55 | 0, // no bad nonce return |
| 56 | RC_PolicyTicket_cpHashA, |
| 57 | RC_PolicyTicket_timeout); |
| 58 | if(result != TPM_RC_SUCCESS) |
| 59 | return result; |
| 60 | |
| 61 | // Validate Ticket |
| 62 | // Re-generate policy ticket by input parameters |
| 63 | TicketComputeAuth(in->ticket.tag, in->ticket.hierarchy, timeout, &in->cpHashA, |
| 64 | &in->policyRef, &in->authName, &ticketToCompare); |
| 65 | |
| 66 | // Compare generated digest with input ticket digest |
| 67 | if(!Memory2BEqual(&in->ticket.digest.b, &ticketToCompare.digest.b)) |
| 68 | return TPM_RC_TICKET + RC_PolicyTicket_ticket; |
| 69 | |
| 70 | // Internal Data Update |
| 71 | |
| 72 | // Is this ticket to take the place of a TPM2_PolicySigned() or |
| 73 | // a TPM2_PolicySecret()? |
| 74 | if(in->ticket.tag == TPM_ST_AUTH_SIGNED) |
| 75 | commandCode = TPM_CC_PolicySigned; |
| 76 | else if(in->ticket.tag == TPM_ST_AUTH_SECRET) |
| 77 | commandCode = TPM_CC_PolicySecret; |
| 78 | else |
| 79 | // There could only be two possible tag values. Any other value should |
| 80 | // be caught by the ticket validation process. |
| 81 | pAssert(FALSE); |
| 82 | |
| 83 | // Update policy context |
| 84 | PolicyContextUpdate(commandCode, &in->authName, &in->policyRef, |
| 85 | &in->cpHashA, timeout, session); |
| 86 | |
| 87 | return TPM_RC_SUCCESS; |
| 88 | } |