examples/aes.c

   1 /*
   2  * Demo on how to use /dev/crypto device for ciphering.
   3  *
   4  * Placed under public domain.
   5  *
   6  */
   7 #include <stdio.h>
   8 #include <string.h>
   9 #include <unistd.h>
  10 #include <fcntl.h>
  11 #include <sys/ioctl.h>
  12 #include <crypto/cryptodev.h>
  13 #include "aes.h"
  14
  15 #define KEY_SIZE        16
  16
  17
  18 int aes_ctx_init(struct cryptodev_ctx* ctx, int cfd, const uint8_t *key, unsigned int key_size)
  19 {
  20 #ifdef CIOCGSESSINFO
  21         struct session_info_op siop;
  22 #endif
  23
  24         memset(ctx, 0, sizeof(*ctx));
  25         ctx->cfd = cfd;
  26
  27         ctx->sess.cipher = CRYPTO_AES_CBC;
  28         ctx->sess.keylen = key_size;
  29         ctx->sess.key = (void*)key;
  30         if (ioctl(ctx->cfd, CIOCGSESSION, &ctx->sess)) {
  31                 perror("ioctl(CIOCGSESSION)");
  32                 return -1;
  33         }
  34
  35 #ifdef CIOCGSESSINFO
  36         siop.ses = ctx->sess.ses;
  37         if (ioctl(ctx->cfd, CIOCGSESSINFO, &siop)) {
  38                 perror("ioctl(CIOCGSESSINFO)");
  39                 return -1;
  40         }
  41         printf("requested cipher CRYPTO_AES_CBC, got %s with driver %s\n",
  42                         siop.cipher_info.cra_name, siop.cipher_info.cra_driver_name);
  43         /*printf("Alignmask is %x\n", (unsigned int)siop.alignmask); */
  44         ctx->alignmask = siop.alignmask;
  45 #endif
  46         return 0;
  47 }
  48
  49 void aes_ctx_deinit(struct cryptodev_ctx* ctx)
  50 {
  51         if (ioctl(ctx->cfd, CIOCFSESSION, &ctx->sess.ses)) {
  52                 perror("ioctl(CIOCFSESSION)");
  53         }
  54 }
  55
  56 int
  57 aes_encrypt(struct cryptodev_ctx* ctx, const void* iv, const void* plaintext, void* ciphertext, size_t size)
  58 {
  59         struct crypt_op cryp;
  60         void* p;
  61
  62         /* check plaintext and ciphertext alignment */
  63         if (ctx->alignmask) {
  64                 p = (void*)(((unsigned long)plaintext + ctx->alignmask) & ~ctx->alignmask);
  65                 if (plaintext != p) {
  66                         fprintf(stderr, "plaintext is not aligned\n");
  67                         return -1;
  68                 }
  69
  70                 p = (void*)(((unsigned long)ciphertext + ctx->alignmask) & ~ctx->alignmask);
  71                 if (ciphertext != p) {
  72                         fprintf(stderr, "ciphertext is not aligned\n");
  73                         return -1;
  74                 }
  75         }
  76
  77         memset(&cryp, 0, sizeof(cryp));
  78
  79         /* Encrypt data.in to data.encrypted */
  80         cryp.ses = ctx->sess.ses;
  81         cryp.len = size;
  82         cryp.src = (void*)plaintext;
  83         cryp.dst = ciphertext;
  84         cryp.iv = (void*)iv;
  85         cryp.op = COP_ENCRYPT;
  86         if (ioctl(ctx->cfd, CIOCCRYPT, &cryp)) {
  87                 perror("ioctl(CIOCCRYPT)");
  88                 return -1;
  89         }
  90
  91         return 0;
  92 }
  93
  94 int
  95 aes_decrypt(struct cryptodev_ctx* ctx, const void* iv, const void* ciphertext, void* plaintext, size_t size)
  96 {
  97         struct crypt_op cryp;
  98         void* p;
  99
 100         /* check plaintext and ciphertext alignment */
 101         if (ctx->alignmask) {
 102                 p = (void*)(((unsigned long)plaintext + ctx->alignmask) & ~ctx->alignmask);
 103                 if (plaintext != p) {
 104                         fprintf(stderr, "plaintext is not aligned\n");
 105                         return -1;
 106                 }
 107
 108                 p = (void*)(((unsigned long)ciphertext + ctx->alignmask) & ~ctx->alignmask);
 109                 if (ciphertext != p) {
 110                         fprintf(stderr, "ciphertext is not aligned\n");
 111                         return -1;
 112                 }
 113         }
 114
 115         memset(&cryp, 0, sizeof(cryp));
 116
 117         /* Encrypt data.in to data.encrypted */
 118         cryp.ses = ctx->sess.ses;
 119         cryp.len = size;
 120         cryp.src = (void*)ciphertext;
 121         cryp.dst = plaintext;
 122         cryp.iv = (void*)iv;
 123         cryp.op = COP_DECRYPT;
 124         if (ioctl(ctx->cfd, CIOCCRYPT, &cryp)) {
 125                 perror("ioctl(CIOCCRYPT)");
 126                 return -1;
 127         }
 128
 129         return 0;
 130 }
 131
 132 static int test_aes(int cfd)
 133 {
 134         char plaintext1_raw[AES_BLOCK_SIZE + 63], *plaintext1;
 135         char ciphertext1[AES_BLOCK_SIZE] = { 0xdf, 0x55, 0x6a, 0x33, 0x43, 0x8d, 0xb8, 0x7b, 0xc4, 0x1b, 0x17, 0x52, 0xc5, 0x5e, 0x5e, 0x49 };
 136         char iv1[AES_BLOCK_SIZE];
 137         uint8_t key1[KEY_SIZE] = { 0xff, 0xff, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
 138         char plaintext2_data[AES_BLOCK_SIZE] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xc0, 0x00 };
 139         char plaintext2_raw[AES_BLOCK_SIZE + 63], *plaintext2;
 140         char ciphertext2[AES_BLOCK_SIZE] = { 0xb7, 0x97, 0x2b, 0x39, 0x41, 0xc4, 0x4b, 0x90, 0xaf, 0xa7, 0xb2, 0x64, 0xbf, 0xba, 0x73, 0x87 };
 141         char iv2[AES_BLOCK_SIZE];
 142         uint8_t key2[KEY_SIZE];
 143         struct cryptodev_ctx ctx;
 144
 145         aes_ctx_init(&ctx, cfd, key1, sizeof(key1));
 146
 147         if (ctx.alignmask)
 148                 plaintext1 = (char *)(((unsigned long)plaintext1_raw + ctx.alignmask) & ~ctx.alignmask);
 149         else
 150                 plaintext1 = plaintext1_raw;
 151
 152         memset(plaintext1, 0x0, AES_BLOCK_SIZE);
 153         memset(iv1, 0x0, sizeof(iv1));
 154
 155         aes_encrypt(&ctx, iv1, plaintext1, plaintext1, AES_BLOCK_SIZE);
 156
 157         /* Verify the result */
 158         if (memcmp(plaintext1, ciphertext1, AES_BLOCK_SIZE) != 0) {
 159                 fprintf(stderr,
 160                         "FAIL: Decrypted data are different from the input data.\n");
 161                 return -1;
 162         }
 163
 164         aes_ctx_deinit(&ctx);
 165
 166         /* Test 2 */
 167
 168         memset(key2, 0x0, sizeof(key2));
 169         memset(iv2, 0x0, sizeof(iv2));
 170
 171         aes_ctx_init(&ctx, cfd, key2, sizeof(key2));
 172
 173         if (ctx.alignmask) {
 174                 plaintext2 = (char *)(((unsigned long)plaintext2_raw + ctx.alignmask) & ~ctx.alignmask);
 175         } else {
 176                 plaintext2 = plaintext2_raw;
 177         }
 178         memcpy(plaintext2, plaintext2_data, AES_BLOCK_SIZE);
 179
 180         /* Encrypt data.in to data.encrypted */
 181         aes_encrypt(&ctx, iv2, plaintext2, plaintext2, AES_BLOCK_SIZE);
 182
 183         /* Verify the result */
 184         if (memcmp(plaintext2, ciphertext2, AES_BLOCK_SIZE) != 0) {
 185                 int i;
 186                 fprintf(stderr,
 187                         "FAIL: Decrypted data are different from the input data.\n");
 188                 printf("plaintext:");
 189                 for (i = 0; i < AES_BLOCK_SIZE; i++) {
 190                         printf("%02x ", plaintext2[i]);
 191                 }
 192                 printf("ciphertext:");
 193                 for (i = 0; i < AES_BLOCK_SIZE; i++) {
 194                         printf("%02x ", ciphertext2[i]);
 195                 }
 196                 printf("\n");
 197                 return 1;
 198         }
 199
 200         aes_ctx_deinit(&ctx);
 201
 202         printf("AES Test passed\n");
 203
 204         return 0;
 205 }
 206
 207 int
 208 main()
 209 {
 210         int cfd = -1;
 211
 212         /* Open the crypto device */
 213         cfd = open("/dev/crypto", O_RDWR, 0);
 214         if (cfd < 0) {
 215                 perror("open(/dev/crypto)");
 216                 return 1;
 217         }
 218
 219         /* Set close-on-exec (not really neede here) */
 220         if (fcntl(cfd, F_SETFD, 1) == -1) {
 221                 perror("fcntl(F_SETFD)");
 222                 return 1;
 223         }
 224
 225         /* Run the test itself */
 226         if (test_aes(cfd))
 227                 return 1;
 228
 229         /* Close the original descriptor */
 230         if (close(cfd)) {
 231                 perror("close(cfd)");
 232                 return 1;
 233         }
 234
 235         return 0;
 236 }
 237