1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * Copyright (c) 2013 The Chromium OS Authors. 4 * Coypright (c) 2013 Guntermann & Drunck GmbH 5 */ 6 7 #ifndef __TPM_UTILS_H 8 #define __TPM_UTILS_H 9 10 #define COMMAND_BUFFER_SIZE 256 11 12 /* Internal error of TPM command library */ 13 #define TPM_LIB_ERROR ((u32)~0u) 14 15 /* To make strings of commands more easily */ 16 #define __MSB(x) ((x) >> 8) 17 #define __LSB(x) ((x) & 0xFF) 18 #define tpm_u16(x) __MSB(x), __LSB(x) 19 #define tpm_u32(x) tpm_u16((x) >> 16), tpm_u16((x) & 0xFFFF) 20 21 /** 22 * tpm_open() - Request access to locality 0 for the caller 23 * 24 * After all commands have been completed the caller is supposed to 25 * call tpm_close(). 26 * 27 * Returns 0 on success, -ve on failure. 28 */ 29 int tpm_open(struct udevice *dev); 30 31 /** 32 * tpm_close() - Close the current session 33 * 34 * Releasing the locked locality. Returns 0 on success, -ve 1 on 35 * failure (in case lock removal did not succeed). 36 */ 37 int tpm_close(struct udevice *dev); 38 39 /** 40 * Pack data into a byte string. The data types are specified in 41 * the format string: 'b' means unsigned byte, 'w' unsigned word, 42 * 'd' unsigned double word, and 's' byte string. The data are a 43 * series of offsets and values (for type byte string there are also 44 * lengths). The data values are packed into the byte string 45 * sequentially, and so a latter value could over-write a former 46 * value. 47 * 48 * @param str output string 49 * @param size size of output string 50 * @param format format string 51 * @param ... data points 52 * @return 0 on success, non-0 on error 53 */ 54 int pack_byte_string(u8 *str, size_t size, const char *format, ...); 55 56 /** 57 * Unpack data from a byte string. The data types are specified in 58 * the format string: 'b' means unsigned byte, 'w' unsigned word, 59 * 'd' unsigned double word, and 's' byte string. The data are a 60 * series of offsets and pointers (for type byte string there are also 61 * lengths). 62 * 63 * @param str output string 64 * @param size size of output string 65 * @param format format string 66 * @param ... data points 67 * @return 0 on success, non-0 on error 68 */ 69 int unpack_byte_string(const u8 *str, size_t size, const char *format, ...); 70 71 /** 72 * Get TPM command size. 73 * 74 * @param command byte string of TPM command 75 * @return command size of the TPM command 76 */ 77 u32 tpm_command_size(const void *command); 78 79 /** 80 * Get TPM response return code, which is one of TPM_RESULT values. 81 * 82 * @param response byte string of TPM response 83 * @return return code of the TPM response 84 */ 85 u32 tpm_return_code(const void *response); 86 87 /** 88 * Send a TPM command and return response's return code, and optionally 89 * return response to caller. 90 * 91 * @param command byte string of TPM command 92 * @param response output buffer for TPM response, or NULL if the 93 * caller does not care about it 94 * @param size_ptr output buffer size (input parameter) and TPM 95 * response length (output parameter); this parameter 96 * is a bidirectional 97 * @return return code of the TPM response 98 */ 99 u32 tpm_sendrecv_command(const void *command, void *response, size_t *size_ptr); 100 101 #endif /* __TPM_UTILS_H */ 102