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 (at) 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 #if IMAGE_ENABLE_SIGN 35 /** 36 * sign() - calculate and return signature for given input data 37 * 38 * @info: Specifies key and FIT information 39 * @data: Pointer to the input data 40 * @data_len: Data length 41 * @sigp: Set to an allocated buffer holding the signature 42 * @sig_len: Set to length of the calculated hash 43 * 44 * This computes input data signature according to selected algorithm. 45 * Resulting signature value is placed in an allocated buffer, the 46 * pointer is returned as *sigp. The length of the calculated 47 * signature is returned via the sig_len pointer argument. The caller 48 * should free *sigp. 49 * 50 * @return: 0, on success, -ve on error 51 */ 52 int rsa_sign(struct image_sign_info *info, 53 const struct image_region region[], 54 int region_count, uint8_t **sigp, uint *sig_len); 55 56 /** 57 * add_verify_data() - Add verification information to FDT 58 * 59 * Add public key information to the FDT node, suitable for 60 * verification at run-time. The information added depends on the 61 * algorithm being used. 62 * 63 * @info: Specifies key and FIT information 64 * @keydest: Destination FDT blob for public key data 65 * @return: 0, on success, -ENOSPC if the keydest FDT blob ran out of space, 66 other -ve value on error 67 */ 68 int rsa_add_verify_data(struct image_sign_info *info, void *keydest); 69 #else 70 static inline int rsa_sign(struct image_sign_info *info, 71 const struct image_region region[], int region_count, 72 uint8_t **sigp, uint *sig_len) 73 { 74 return -ENXIO; 75 } 76 77 static inline int rsa_add_verify_data(struct image_sign_info *info, 78 void *keydest) 79 { 80 return -ENXIO; 81 } 82 #endif 83 84 #if IMAGE_ENABLE_VERIFY 85 /** 86 * rsa_verify() - Verify a signature against some data 87 * 88 * Verify a RSA PKCS1.5 signature against an expected hash. 89 * 90 * @info: Specifies key and FIT information 91 * @data: Pointer to the input data 92 * @data_len: Data length 93 * @sig: Signature 94 * @sig_len: Number of bytes in signature 95 * @return 0 if verified, -ve on error 96 */ 97 int rsa_verify(struct image_sign_info *info, 98 const struct image_region region[], int region_count, 99 uint8_t *sig, uint sig_len); 100 #else 101 static inline int rsa_verify(struct image_sign_info *info, 102 const struct image_region region[], int region_count, 103 uint8_t *sig, uint sig_len) 104 { 105 return -ENXIO; 106 } 107 #endif 108 109 #define RSA2048_BYTES (2048 / 8) 110 #define RSA4096_BYTES (4096 / 8) 111 112 /* This is the minimum/maximum key size we support, in bits */ 113 #define RSA_MIN_KEY_BITS 2048 114 #define RSA_MAX_KEY_BITS 4096 115 116 /* This is the maximum signature length that we support, in bits */ 117 #define RSA_MAX_SIG_BITS 4096 118 119 #endif 120
