| /* Copyright lowRISC contributors. */ | |
| /* Licensed under the Apache License, Version 2.0, see LICENSE for details. */ | |
| /* SPDX-License-Identifier: Apache-2.0 */ | |
| .text | |
| .globl rsa_encrypt | |
| rsa_encrypt: | |
| jal x1, modload | |
| jal x1, modexp_65537 | |
| ecall | |
| /** | |
| * RSA decryption | |
| */ | |
| .globl rsa_decrypt | |
| rsa_decrypt: | |
| jal x1, modload | |
| jal x1, modexp | |
| ecall | |
| .data | |
| /* | |
| The structure of the 256b below are mandated by the calling convention of the | |
| RSA library. | |
| */ | |
| /* reserved */ | |
| .word 0x00000000 | |
| /* N: Key/modulus size in 256b limbs (i.e. for RSA-1024: N = 4) */ | |
| .globl n_limbs | |
| n_limbs: | |
| .word 0x00000000 | |
| /* pointer to m0' (dptr_m0d) */ | |
| dptr_m0d: | |
| .word m0d | |
| /* pointer to RR (dptr_rr) */ | |
| dptr_rr: | |
| .word RR | |
| /* load pointer to modulus (dptr_m) */ | |
| dptr_m: | |
| .word modulus | |
| /* pointer to base bignum buffer (dptr_in) */ | |
| dptr_in: | |
| .word in | |
| /* pointer to exponent buffer (dptr_exp, unused for encrypt) */ | |
| dptr_exp: | |
| .word exp | |
| /* pointer to out buffer (dptr_out) */ | |
| dptr_out: | |
| .word out | |
| /* Freely available DMEM space. */ | |
| m0d: | |
| /* filled by modload */ | |
| .zero 512 | |
| RR: | |
| /* filled by modload */ | |
| .zero 512 | |
| /* Modulus (n) */ | |
| .globl modulus | |
| modulus: | |
| .zero 512 | |
| /* private exponent (d) */ | |
| .globl exp | |
| exp: | |
| .zero 512 | |
| /* input data */ | |
| .globl in | |
| in: | |
| .zero 512 | |
| /* output data */ | |
| .globl out | |
| out: | |
| .zero 512 |