1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * Copyright (c) 2013, Google Inc. 4 * 5 * (C) Copyright 2008 Semihalf 6 * 7 * (C) Copyright 2000-2006 8 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. 9 */ 10 11 #ifndef _RSA_H 12 #define _RSA_H 13 14 #include <errno.h> 15 #include <image.h> 16 17 /** 18 * struct rsa_public_key - holder for a public key 19 * 20 * An RSA public key consists of a modulus (typically called N), the inverse 21 * and R^2, where R is 2^(# key bits). 22 */ 23 24 struct rsa_public_key { 25 uint len; /* len of modulus[] in number of uint32_t */ 26 uint32_t n0inv; /* -1 / modulus[0] mod 2^32 */ 27 uint32_t *modulus; /* modulus as little endian array */ 28 uint32_t *rr; /* R^2 as little endian array */ 29 uint64_t exponent; /* public exponent */ 30 }; 31 32 struct image_sign_info; 33 34 /** 35 * sign() - calculate and return signature for given input data 36 * 37 * @info: Specifies key and FIT information 38 * @data: Pointer to the input data 39 * @data_len: Data length 40 * @sigp: Set to an allocated buffer holding the signature 41 * @sig_len: Set to length of the calculated hash 42 * 43 * This computes input data signature according to selected algorithm. 44 * Resulting signature value is placed in an allocated buffer, the 45 * pointer is returned as *sigp. The length of the calculated 46 * signature is returned via the sig_len pointer argument. The caller 47 * should free *sigp. 48 * 49 * @return: 0, on success, -ve on error 50 */ 51 int rsa_sign(struct image_sign_info *info, 52 const struct image_region region[], 53 int region_count, uint8_t **sigp, uint *sig_len); 54 55 /** 56 * add_verify_data() - Add verification information to FDT 57 * 58 * Add public key information to the FDT node, suitable for 59 * verification at run-time. The information added depends on the 60 * algorithm being used. 61 * 62 * @info: Specifies key and FIT information 63 * @keydest: Destination FDT blob for public key data 64 * @return: node offset within the FDT blob where the data was written on 65 * success, -ENOSPC if the keydest FDT blob ran out of space, other -ve 66 * value on other error 67 */ 68 int rsa_add_verify_data(struct image_sign_info *info, void *keydest); 69 70 /** 71 * rsa_verify_hash() - Verify a signature against a hash 72 * 73 * Verify a RSA PKCS1.5 signature against an expected hash. 74 * 75 * @info: Specifies key and FIT information 76 * @hash: Hash according to algorithm specified in @info 77 * @sig: Signature 78 * @sig_len: Number of bytes in signature 79 * Return: 0 if verified, -ve on error 80 */ 81 int rsa_verify_hash(struct image_sign_info *info, 82 const uint8_t *hash, uint8_t *sig, uint sig_len); 83 84 /** 85 * rsa_verify() - Verify a signature against some data 86 * 87 * Verify a RSA PKCS1.5 signature against an expected hash. 88 * 89 * @info: Specifies key and FIT information 90 * @data: Pointer to the input data 91 * @data_len: Data length 92 * @sig: Signature 93 * @sig_len: Number of bytes in signature 94 * Return: 0 if verified, -ve on error 95 */ 96 int rsa_verify(struct image_sign_info *info, 97 const struct image_region region[], int region_count, 98 uint8_t *sig, uint sig_len); 99 100 int rsa_verify_with_pkey(struct image_sign_info *info, 101 const void *hash, uint8_t *sig, uint sig_len); 102 103 int padding_pkcs_15_verify(struct image_sign_info *info, 104 const uint8_t *msg, int msg_len, 105 const uint8_t *hash, int hash_len); 106 107 int padding_pss_verify(struct image_sign_info *info, 108 const uint8_t *msg, int msg_len, 109 const uint8_t *hash, int hash_len); 110 111 #define RSA_DEFAULT_PADDING_NAME "pkcs-1.5" 112 113 #define RSA2048_BYTES (2048 / 8) 114 #define RSA3072_BYTES (3072 / 8) 115 #define RSA4096_BYTES (4096 / 8) 116 117 /* This is the minimum/maximum key size we support, in bits */ 118 #define RSA_MIN_KEY_BITS 2048 119 #define RSA_MAX_KEY_BITS 4096 120 121 /* This is the maximum signature length that we support, in bits */ 122 #define RSA_MAX_SIG_BITS 4096 123 124 #endif 125