1 /*
2 * Copyright (c) 2001-2019, Arm Limited and Contributors. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7 #define CC_PAL_LOG_CUR_COMPONENT HOST_LOG_MASK_SECURE_BOOT
8
9 /************* Include Files ****************/
10 #include "rsa_pki_pka.h"
11 #include "rsa_bsv.h"
12
13 /************************ Defines ******************************/
14
15 /************************ Enums ******************************/
16
17 /************************ Typedefs ******************************/
18
19 /************************ Global Data ******************************/
20
21 #ifdef PKA_DEBUG
22 extern uint8_t tempRes[SB_CERT_RSA_KEY_SIZE_IN_WORDS+2*RSA_PKA_BIG_WORD_SIZE_IN_32_BIT_WORDS];
23 extern uint32_t g_SramPkaAddr;
24 #endif
25
26 /* ********** Internal private functions ****************** */
27
28
29 /* ************************** public functions ********************************* */
30
31
32 /**
33 * @brief The RSA_CalcExponent calculates The following:
34 *
35 * Res = (Base ^ Exp) mod N. ( Exp = 0x10001 )
36 *
37 * The calculation is done in a secured way using the PIC.
38 *
39 * @hwBaseAddress - Cryptocell base address
40 * @Base_ptr[in] - The pointer to the base buffer.
41 * @N_ptr[in] - The pointer to the modulus buffer.
42 * @Np_ptr[in] - The Np vector buffer..
43 * - Its size must be 160.
44 * @Res_ptr[out] - The pointer to the buffer that will contain the result.
45 *
46 * @return CCError_t - On success CC_OK is returned, on failure a
47 * value MODULE_* as defined in ...
48 */
RSA_CalcExponent(unsigned long hwBaseAddress,uint32_t * Base_ptr,uint32_t * N_ptr,uint32_t * Np_ptr,uint32_t * Res_ptr)49 void RSA_CalcExponent( unsigned long hwBaseAddress,
50 uint32_t *Base_ptr,
51 uint32_t *N_ptr,
52 uint32_t *Np_ptr,
53 uint32_t *Res_ptr )
54 {
55
56 /* Fix value for the Exponent */
57 uint32_t Exp = RSA_EXP_VAL;
58 uint32_t regsCount = 7; /*5 working + 2 temp registers*/
59
60 /* FUNCTION LOGIC */
61
62 /* .................... initialize local variables ...................... */
63 /* ---------------------------------------------------------------------- */
64
65 /* initialize the PKA engine on default mode */
66 RSA_PKA_InitPka(SB_CERT_RSA_KEY_SIZE_IN_BITS, regsCount, hwBaseAddress);
67
68 /* copy modulus N into r0 register */
69 RSA_HW_PKI_PKA_CopyDataIntoPkaReg( 0/*dstReg*/, 1/*LenID*/,
70 N_ptr/*src_ptr*/, SB_CERT_RSA_KEY_SIZE_IN_WORDS, hwBaseAddress );
71
72 /* copy the NP into r1 register NP */
73 RSA_HW_PKI_PKA_CopyDataIntoPkaReg( 1/*dstReg*/, 1/*LenID*/, Np_ptr/*src_ptr*/,
74 RSA_HW_PKI_PKA_BARRETT_MOD_TAG_SIZE_IN_WORDS, hwBaseAddress );
75
76 /* copy input data into PKI register: DataIn=>r2 */
77 RSA_HW_PKI_PKA_CopyDataIntoPkaReg( 2/*dstReg*/, 1/*LenID*/,
78 Base_ptr, SB_CERT_RSA_KEY_SIZE_IN_WORDS, hwBaseAddress );
79
80 /* copy exponent data PKI register: e=>r3 */
81 RSA_HW_PKI_PKA_CopyDataIntoPkaReg( 3/*dstReg*/, 1/*LenID*/,
82 &Exp, RSA_EXP_SIZE_WORDS, hwBaseAddress );
83
84
85 /* .. calculate the exponent Res = OpA**OpB mod N; ... */
86 /* -------------------------------------------------------------------- */
87 RSA_HW_PKI_PKA_ModExp( 0/*LenID*/, 2/*OpA*/, 3/*OpB*/, 4/*Res*/, 0/*Tag*/, hwBaseAddress );
88
89 /* copy result into output: r4 =>DataOut */
90 RSA_HW_PKI_PKA_CopyDataFromPkaReg( Res_ptr, SB_CERT_RSA_KEY_SIZE_IN_WORDS,
91 4/*srcReg*/, hwBaseAddress );
92
93 /* Finish PKA operations (waiting PKI done and close PKA clocks) */
94 RSA_HW_PKI_PKA_FinishPKA( hwBaseAddress );
95
96 }/* END OF RSA_CalcExponent */
97
