Longpeng(Mike) | 25c60df | 2017-07-14 14:04:06 -0400 | [diff] [blame] | 1 | /* |
| 2 | * QEMU Crypto af_alg-backend cipher support |
| 3 | * |
| 4 | * Copyright (c) 2017 HUAWEI TECHNOLOGIES CO., LTD. |
| 5 | * |
| 6 | * Authors: |
| 7 | * Longpeng(Mike) <longpeng2@huawei.com> |
| 8 | * |
| 9 | * This work is licensed under the terms of the GNU GPL, version 2 or |
| 10 | * (at your option) any later version. See the COPYING file in the |
| 11 | * top-level directory. |
| 12 | */ |
| 13 | #include "qemu/osdep.h" |
| 14 | #include "qemu/sockets.h" |
| 15 | #include "qemu-common.h" |
| 16 | #include "qapi/error.h" |
| 17 | #include "crypto/cipher.h" |
| 18 | #include "cipherpriv.h" |
| 19 | |
| 20 | |
| 21 | static char * |
| 22 | qcrypto_afalg_cipher_format_name(QCryptoCipherAlgorithm alg, |
| 23 | QCryptoCipherMode mode, |
| 24 | Error **errp) |
| 25 | { |
| 26 | char *name; |
| 27 | const char *alg_name; |
| 28 | const char *mode_name; |
| 29 | |
| 30 | switch (alg) { |
| 31 | case QCRYPTO_CIPHER_ALG_AES_128: |
| 32 | case QCRYPTO_CIPHER_ALG_AES_192: |
| 33 | case QCRYPTO_CIPHER_ALG_AES_256: |
| 34 | alg_name = "aes"; |
| 35 | break; |
| 36 | case QCRYPTO_CIPHER_ALG_CAST5_128: |
| 37 | alg_name = "cast5"; |
| 38 | break; |
| 39 | case QCRYPTO_CIPHER_ALG_SERPENT_128: |
| 40 | case QCRYPTO_CIPHER_ALG_SERPENT_192: |
| 41 | case QCRYPTO_CIPHER_ALG_SERPENT_256: |
| 42 | alg_name = "serpent"; |
| 43 | break; |
| 44 | case QCRYPTO_CIPHER_ALG_TWOFISH_128: |
| 45 | case QCRYPTO_CIPHER_ALG_TWOFISH_192: |
| 46 | case QCRYPTO_CIPHER_ALG_TWOFISH_256: |
| 47 | alg_name = "twofish"; |
| 48 | break; |
| 49 | |
| 50 | default: |
| 51 | error_setg(errp, "Unsupported cipher algorithm %d", alg); |
| 52 | return NULL; |
| 53 | } |
| 54 | |
Markus Armbruster | 977c736 | 2017-08-24 10:46:08 +0200 | [diff] [blame] | 55 | mode_name = QCryptoCipherMode_str(mode); |
Longpeng(Mike) | 25c60df | 2017-07-14 14:04:06 -0400 | [diff] [blame] | 56 | name = g_strdup_printf("%s(%s)", mode_name, alg_name); |
| 57 | |
| 58 | return name; |
| 59 | } |
| 60 | |
| 61 | QCryptoAFAlg * |
| 62 | qcrypto_afalg_cipher_ctx_new(QCryptoCipherAlgorithm alg, |
| 63 | QCryptoCipherMode mode, |
| 64 | const uint8_t *key, |
| 65 | size_t nkey, Error **errp) |
| 66 | { |
| 67 | QCryptoAFAlg *afalg; |
| 68 | size_t expect_niv; |
| 69 | char *name; |
| 70 | |
| 71 | name = qcrypto_afalg_cipher_format_name(alg, mode, errp); |
| 72 | if (!name) { |
| 73 | return NULL; |
| 74 | } |
| 75 | |
| 76 | afalg = qcrypto_afalg_comm_alloc(AFALG_TYPE_CIPHER, name, errp); |
| 77 | if (!afalg) { |
| 78 | g_free(name); |
| 79 | return NULL; |
| 80 | } |
| 81 | |
| 82 | g_free(name); |
| 83 | |
| 84 | /* setkey */ |
| 85 | if (qemu_setsockopt(afalg->tfmfd, SOL_ALG, ALG_SET_KEY, key, |
| 86 | nkey) != 0) { |
| 87 | error_setg_errno(errp, errno, "Set key failed"); |
| 88 | qcrypto_afalg_comm_free(afalg); |
| 89 | return NULL; |
| 90 | } |
| 91 | |
| 92 | /* prepare msg header */ |
| 93 | afalg->msg = g_new0(struct msghdr, 1); |
| 94 | afalg->msg->msg_controllen += CMSG_SPACE(ALG_OPTYPE_LEN); |
| 95 | expect_niv = qcrypto_cipher_get_iv_len(alg, mode); |
| 96 | if (expect_niv) { |
| 97 | afalg->msg->msg_controllen += CMSG_SPACE(ALG_MSGIV_LEN(expect_niv)); |
| 98 | } |
| 99 | afalg->msg->msg_control = g_new0(uint8_t, afalg->msg->msg_controllen); |
| 100 | |
| 101 | /* We use 1st msghdr for crypto-info and 2nd msghdr for IV-info */ |
| 102 | afalg->cmsg = CMSG_FIRSTHDR(afalg->msg); |
| 103 | afalg->cmsg->cmsg_type = ALG_SET_OP; |
| 104 | afalg->cmsg->cmsg_len = CMSG_SPACE(ALG_OPTYPE_LEN); |
| 105 | if (expect_niv) { |
| 106 | afalg->cmsg = CMSG_NXTHDR(afalg->msg, afalg->cmsg); |
| 107 | afalg->cmsg->cmsg_type = ALG_SET_IV; |
| 108 | afalg->cmsg->cmsg_len = CMSG_SPACE(ALG_MSGIV_LEN(expect_niv)); |
| 109 | } |
| 110 | afalg->cmsg = CMSG_FIRSTHDR(afalg->msg); |
| 111 | |
| 112 | return afalg; |
| 113 | } |
| 114 | |
| 115 | static int |
| 116 | qcrypto_afalg_cipher_setiv(QCryptoCipher *cipher, |
| 117 | const uint8_t *iv, |
| 118 | size_t niv, Error **errp) |
| 119 | { |
| 120 | struct af_alg_iv *alg_iv; |
| 121 | size_t expect_niv; |
| 122 | QCryptoAFAlg *afalg = cipher->opaque; |
| 123 | |
| 124 | expect_niv = qcrypto_cipher_get_iv_len(cipher->alg, cipher->mode); |
| 125 | if (niv != expect_niv) { |
| 126 | error_setg(errp, "Set IV len(%zu) not match expected(%zu)", |
| 127 | niv, expect_niv); |
| 128 | return -1; |
| 129 | } |
| 130 | |
| 131 | /* move ->cmsg to next msghdr, for IV-info */ |
| 132 | afalg->cmsg = CMSG_NXTHDR(afalg->msg, afalg->cmsg); |
| 133 | |
| 134 | /* build setiv msg */ |
| 135 | afalg->cmsg->cmsg_level = SOL_ALG; |
| 136 | alg_iv = (struct af_alg_iv *)CMSG_DATA(afalg->cmsg); |
| 137 | alg_iv->ivlen = niv; |
| 138 | memcpy(alg_iv->iv, iv, niv); |
| 139 | |
| 140 | return 0; |
| 141 | } |
| 142 | |
| 143 | static int |
| 144 | qcrypto_afalg_cipher_op(QCryptoAFAlg *afalg, |
| 145 | const void *in, void *out, |
| 146 | size_t len, bool do_encrypt, |
| 147 | Error **errp) |
| 148 | { |
| 149 | uint32_t *type = NULL; |
| 150 | struct iovec iov; |
| 151 | size_t ret, rlen, done = 0; |
| 152 | uint32_t origin_controllen; |
| 153 | |
| 154 | origin_controllen = afalg->msg->msg_controllen; |
| 155 | /* movev ->cmsg to first header, for crypto-info */ |
| 156 | afalg->cmsg = CMSG_FIRSTHDR(afalg->msg); |
| 157 | |
| 158 | /* build encrypt msg */ |
| 159 | afalg->cmsg->cmsg_level = SOL_ALG; |
| 160 | afalg->msg->msg_iov = &iov; |
| 161 | afalg->msg->msg_iovlen = 1; |
| 162 | type = (uint32_t *)CMSG_DATA(afalg->cmsg); |
| 163 | if (do_encrypt) { |
| 164 | *type = ALG_OP_ENCRYPT; |
| 165 | } else { |
| 166 | *type = ALG_OP_DECRYPT; |
| 167 | } |
| 168 | |
| 169 | do { |
| 170 | iov.iov_base = (void *)in + done; |
| 171 | iov.iov_len = len - done; |
| 172 | |
| 173 | /* send info to AF_ALG core */ |
| 174 | ret = sendmsg(afalg->opfd, afalg->msg, 0); |
| 175 | if (ret == -1) { |
| 176 | error_setg_errno(errp, errno, "Send data to AF_ALG core failed"); |
| 177 | return -1; |
| 178 | } |
| 179 | |
| 180 | /* encrypto && get result */ |
| 181 | rlen = read(afalg->opfd, out, ret); |
| 182 | if (rlen == -1) { |
| 183 | error_setg_errno(errp, errno, "Get result from AF_ALG core failed"); |
| 184 | return -1; |
| 185 | } |
| 186 | assert(rlen == ret); |
| 187 | |
| 188 | /* do not update IV for following chunks */ |
| 189 | afalg->msg->msg_controllen = 0; |
| 190 | done += ret; |
| 191 | } while (done < len); |
| 192 | |
| 193 | afalg->msg->msg_controllen = origin_controllen; |
| 194 | |
| 195 | return 0; |
| 196 | } |
| 197 | |
| 198 | static int |
| 199 | qcrypto_afalg_cipher_encrypt(QCryptoCipher *cipher, |
| 200 | const void *in, void *out, |
| 201 | size_t len, Error **errp) |
| 202 | { |
| 203 | return qcrypto_afalg_cipher_op(cipher->opaque, in, out, |
| 204 | len, true, errp); |
| 205 | } |
| 206 | |
| 207 | static int |
| 208 | qcrypto_afalg_cipher_decrypt(QCryptoCipher *cipher, |
| 209 | const void *in, void *out, |
| 210 | size_t len, Error **errp) |
| 211 | { |
| 212 | return qcrypto_afalg_cipher_op(cipher->opaque, in, out, |
| 213 | len, false, errp); |
| 214 | } |
| 215 | |
| 216 | static void qcrypto_afalg_comm_ctx_free(QCryptoCipher *cipher) |
| 217 | { |
| 218 | qcrypto_afalg_comm_free(cipher->opaque); |
| 219 | } |
| 220 | |
| 221 | struct QCryptoCipherDriver qcrypto_cipher_afalg_driver = { |
| 222 | .cipher_encrypt = qcrypto_afalg_cipher_encrypt, |
| 223 | .cipher_decrypt = qcrypto_afalg_cipher_decrypt, |
| 224 | .cipher_setiv = qcrypto_afalg_cipher_setiv, |
| 225 | .cipher_free = qcrypto_afalg_comm_ctx_free, |
| 226 | }; |