1Tss2_Tcti_Cmd_Init(3) Library Functions Manual Tss2_Tcti_Cmd_Init(3)
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6 Tss2_Tcti_Cmd_Init - Initialization function for the Cmd TCTI library.
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9 #include <tss2/tss2_tcti_cmd.h>
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11 TSS2_RC Tss2_Tcti_Cmd_Init (TSS2_TCTI_CONTEXT *tctiContext, size_t
12 *contextSize, const char *conf);
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14 The Tss2_Tcti_Cmd_Init() function initializes a TCTI context used to
15 communicate with a subprocess specified in the conf string. TCTI send
16 and receives utilize the sub-process's stdio and stdout respectively.
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19 Tss2_Tcti_Cmd_Init() attempts to initialize a caller allocated
20 tcti_context of size size using caller provided configuration string
21 conf . Since the tcti_context must be a caller allocated buffer, the
22 caller needs to know the buffer size required by the TCTI library. The
23 minimum size of this context can be discovered by providing NULL for
24 the tcti_context and a non- NULL size parameter. The initialization
25 function will then populate the size parameter with the minimum size of
26 the tcti_context buffer. The caller must then allocate a buffer of this
27 size (or larger) and call Tss2_Tcti_Cmd_Init () again providing the
28 newly allocated tcti_context and the size of this context in the size
29 parameter. This pattern is common to all TCTI initialization functions.
30 We provide an example of this pattern using the Tss2_Tcti_Cmd_Init()
31 function in the section titled EXAMPLE.
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33 The conf parameter is a C string used to configure the TCTI context.
34 This configuration string is the command used for popen(3). The conf
35 string cannot be NULL for this TCTI.
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37 Once initialized, the TCTI context returned exposes the Trusted Comput‐
38 ing Group (TCG) defined API for the lowest level communication with the
39 TPM. Using this API the caller can exchange (send / receive) TPM2 com‐
40 mand and response buffers with a service that can excahnge TPM2 command
41 and response buffers. In nearly all cases however, the caller will ini‐
42 tialize a context using this function before passing the context to a
43 higher level API like the System API (SAPI), Enhanced System API
44 (ESAPI) or Feature API (FAPI) and then never touch it again.
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46 For a more thorough discussion of the TCTI API see the “TSS System
47 Level API and TPM Command Transmission Interface Specification” as pub‐
48 lished by the TCG:
49 https://trustedcomputinggroup.org/tss-system-level-api-tpm-command-transmission-interface-specification/
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52 A successful call to Tss2_Tcti_Cmd_Init() will return TSS2_RC_SUCCESS.
53 An unsuccessful call will produce a response code described in section
54 ERRORS.
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57 TSS2_TCTI_RC_BAD_VALUE is returned if both the tcti_context and the
58 size parameters are NULL, or if the config parameter is NULL.
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61 TCTI initialization fragment:
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63 #include <inttypes.h>
64 #include <stdlib.h>
65 #include <stdio.h>
66 #include <tcti/tcti_mssim.h>
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68 TSS2_RC rc;
69 TSS2_TCTI_CONTEXT *tcti_context;
70 size_t size;
71 const char *conf = "XXX TODO SAMPLE"
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73 rc = Tss2_Tcti_Cmd_Init (NULL, &size, NULL);
74 if (rc != TSS2_RC_SUCCESS) {
75 fprintf (stderr, "Failed to get allocation size for mssim TCTI "
76 " context: 0x%" PRIx32 "0, rc);
77 exit (EXIT_FAILURE);
78 }
79 tcti_context = calloc (1, size);
80 if (tcti_context == NULL) {
81 fprintf (stderr, "Allocation for TCTI context failed: %s0,
82 strerror (errno));
83 exit (EXIT_FAILURE);
84 }
85 rc = Tss2_Tcti_Cmd_Init (&tcti_context, &size, conf);
86 if (rc != TSS2_RC_SUCCESS) {
87 fprintf (stderr, "Failed to initialize mssim TCTI context: "
88 "0x%" PRIx32 "0, rc);
89 free (tcti_context);
90 exit (EXIT_FAILURE);
91 }
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94 Philip Tricca <philip.b.tricca@intel.com>
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97 Tss2_Tcti_Device_Init(3), Tss2_Tcti_Socket_Init(3), Tss2_TctiLdr_Ini‐
98 tialize(3), Tss2_TctiLdr_Finalize(3), tcti-device(7), tcti-socket(7),
99 tcti-tabrmd(7), tpm2-abrmd(8)
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102 This page is part of release 3.2.0 of Open Source implementation of the
103 TCG TPM2 Software Stack (TSS2). A description of the project, informa‐
104 tion about reporting bugs, and the latest version of this page can be
105 found at https://github.com/tpm2-software/tpm2-tss/.
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109TPM2 Software Stack MAY 2020 Tss2_Tcti_Cmd_Init(3)