1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* Kerberos 5 crypto 3 * 4 * Copyright (C) 2025 Red Hat, Inc. All Rights Reserved. 5 * Written by David Howells (dhowells@redhat.com) 6 */ 7 8 #ifndef _CRYPTO_KRB5_H 9 #define _CRYPTO_KRB5_H 10 11 #include <linux/crypto.h> 12 #include <crypto/aead.h> 13 #include <crypto/hash.h> 14 15 struct crypto_shash; 16 struct scatterlist; 17 18 /* 19 * Per Kerberos v5 protocol spec crypto types from the wire. These get mapped 20 * to linux kernel crypto routines. 21 */ 22 #define KRB5_ENCTYPE_NULL 0x0000 23 #define KRB5_ENCTYPE_DES_CBC_CRC 0x0001 /* DES cbc mode with CRC-32 */ 24 #define KRB5_ENCTYPE_DES_CBC_MD4 0x0002 /* DES cbc mode with RSA-MD4 */ 25 #define KRB5_ENCTYPE_DES_CBC_MD5 0x0003 /* DES cbc mode with RSA-MD5 */ 26 #define KRB5_ENCTYPE_DES_CBC_RAW 0x0004 /* DES cbc mode raw */ 27 /* XXX deprecated? */ 28 #define KRB5_ENCTYPE_DES3_CBC_SHA 0x0005 /* DES-3 cbc mode with NIST-SHA */ 29 #define KRB5_ENCTYPE_DES3_CBC_RAW 0x0006 /* DES-3 cbc mode raw */ 30 #define KRB5_ENCTYPE_DES_HMAC_SHA1 0x0008 31 #define KRB5_ENCTYPE_DES3_CBC_SHA1 0x0010 32 #define KRB5_ENCTYPE_AES128_CTS_HMAC_SHA1_96 0x0011 33 #define KRB5_ENCTYPE_AES256_CTS_HMAC_SHA1_96 0x0012 34 #define KRB5_ENCTYPE_ARCFOUR_HMAC 0x0017 35 #define KRB5_ENCTYPE_ARCFOUR_HMAC_EXP 0x0018 36 #define KRB5_ENCTYPE_UNKNOWN 0x01ff 37 38 #define KRB5_CKSUMTYPE_CRC32 0x0001 39 #define KRB5_CKSUMTYPE_RSA_MD4 0x0002 40 #define KRB5_CKSUMTYPE_RSA_MD4_DES 0x0003 41 #define KRB5_CKSUMTYPE_DESCBC 0x0004 42 #define KRB5_CKSUMTYPE_RSA_MD5 0x0007 43 #define KRB5_CKSUMTYPE_RSA_MD5_DES 0x0008 44 #define KRB5_CKSUMTYPE_NIST_SHA 0x0009 45 #define KRB5_CKSUMTYPE_HMAC_SHA1_DES3 0x000c 46 #define KRB5_CKSUMTYPE_HMAC_SHA1_96_AES128 0x000f 47 #define KRB5_CKSUMTYPE_HMAC_SHA1_96_AES256 0x0010 48 #define KRB5_CKSUMTYPE_HMAC_MD5_ARCFOUR -138 /* Microsoft md5 hmac cksumtype */ 49 50 /* 51 * Constants used for key derivation 52 */ 53 /* from rfc3961 */ 54 #define KEY_USAGE_SEED_CHECKSUM (0x99) 55 #define KEY_USAGE_SEED_ENCRYPTION (0xAA) 56 #define KEY_USAGE_SEED_INTEGRITY (0x55) 57 58 /* 59 * Mode of operation. 60 */ 61 enum krb5_crypto_mode { 62 KRB5_CHECKSUM_MODE, /* Checksum only */ 63 KRB5_ENCRYPT_MODE, /* Fully encrypted, possibly with integrity checksum */ 64 }; 65 66 struct krb5_buffer { 67 unsigned int len; 68 void *data; 69 }; 70 71 /* 72 * Kerberos encoding type definition. 73 */ 74 struct krb5_enctype { 75 int etype; /* Encryption (key) type */ 76 int ctype; /* Checksum type */ 77 const char *name; /* "Friendly" name */ 78 const char *encrypt_name; /* Crypto encrypt+checksum name */ 79 const char *cksum_name; /* Crypto checksum name */ 80 const char *hash_name; /* Crypto hash name */ 81 const char *derivation_enc; /* Cipher used in key derivation */ 82 u16 block_len; /* Length of encryption block */ 83 u16 conf_len; /* Length of confounder (normally == block_len) */ 84 u16 cksum_len; /* Length of checksum */ 85 u16 key_bytes; /* Length of raw key, in bytes */ 86 u16 key_len; /* Length of final key, in bytes */ 87 u16 hash_len; /* Length of hash in bytes */ 88 u16 prf_len; /* Length of PRF() result in bytes */ 89 u16 Kc_len; /* Length of Kc in bytes */ 90 u16 Ke_len; /* Length of Ke in bytes */ 91 u16 Ki_len; /* Length of Ki in bytes */ 92 bool keyed_cksum; /* T if a keyed cksum */ 93 94 const struct krb5_crypto_profile *profile; 95 96 int (*random_to_key)(const struct krb5_enctype *krb5, 97 const struct krb5_buffer *in, 98 struct krb5_buffer *out); /* complete key generation */ 99 }; 100 101 /* 102 * krb5_api.c 103 */ 104 const struct krb5_enctype *crypto_krb5_find_enctype(u32 enctype); 105 size_t crypto_krb5_how_much_buffer(const struct krb5_enctype *krb5, 106 enum krb5_crypto_mode mode, 107 size_t data_size, size_t *_offset); 108 size_t crypto_krb5_how_much_data(const struct krb5_enctype *krb5, 109 enum krb5_crypto_mode mode, 110 size_t *_buffer_size, size_t *_offset); 111 void crypto_krb5_where_is_the_data(const struct krb5_enctype *krb5, 112 enum krb5_crypto_mode mode, 113 size_t *_offset, size_t *_len); 114 struct crypto_aead *crypto_krb5_prepare_encryption(const struct krb5_enctype *krb5, 115 const struct krb5_buffer *TK, 116 u32 usage, gfp_t gfp); 117 struct crypto_shash *crypto_krb5_prepare_checksum(const struct krb5_enctype *krb5, 118 const struct krb5_buffer *TK, 119 u32 usage, gfp_t gfp); 120 ssize_t crypto_krb5_encrypt(const struct krb5_enctype *krb5, 121 struct crypto_aead *aead, 122 struct scatterlist *sg, unsigned int nr_sg, 123 size_t sg_len, 124 size_t data_offset, size_t data_len, 125 bool preconfounded); 126 int crypto_krb5_decrypt(const struct krb5_enctype *krb5, 127 struct crypto_aead *aead, 128 struct scatterlist *sg, unsigned int nr_sg, 129 size_t *_offset, size_t *_len); 130 ssize_t crypto_krb5_get_mic(const struct krb5_enctype *krb5, 131 struct crypto_shash *shash, 132 const struct krb5_buffer *metadata, 133 struct scatterlist *sg, unsigned int nr_sg, 134 size_t sg_len, 135 size_t data_offset, size_t data_len); 136 int crypto_krb5_verify_mic(const struct krb5_enctype *krb5, 137 struct crypto_shash *shash, 138 const struct krb5_buffer *metadata, 139 struct scatterlist *sg, unsigned int nr_sg, 140 size_t *_offset, size_t *_len); 141 142 #endif /* _CRYPTO_KRB5_H */ 143