+/* Ciphers. */
+
+typedef struct _gc_cipher_ctx {
+ Gc_cipher alg;
+ Gc_cipher_mode mode;
+#ifdef GNULIB_GC_ARCTWO
+ arctwo_context arctwoContext;
+ char arctwoIV[ARCTWO_BLOCK_SIZE];
+#endif
+#ifdef GNULIB_GC_ARCFOUR
+ arcfour_context arcfourContext;
+#endif
+#ifdef GNULIB_GC_DES
+ des_ctx desContext;
+#endif
+#ifdef GNULIB_GC_RIJNDAEL
+ rijndaelKeyInstance aesEncKey;
+ rijndaelKeyInstance aesDecKey;
+ rijndaelCipherInstance aesContext;
+#endif
+} _gc_cipher_ctx;
+
+Gc_rc
+gc_cipher_open (Gc_cipher alg, Gc_cipher_mode mode,
+ gc_cipher_handle * outhandle)
+{
+ _gc_cipher_ctx *ctx;
+ Gc_rc rc = GC_OK;
+
+ ctx = calloc (sizeof (*ctx), 1);
+ if (!ctx)
+ return GC_MALLOC_ERROR;
+
+ ctx->alg = alg;
+ ctx->mode = mode;
+
+ switch (alg)
+ {
+#ifdef GNULIB_GC_ARCTWO
+ case GC_ARCTWO40:
+ switch (mode)
+ {
+ case GC_ECB:
+ case GC_CBC:
+ break;
+
+ default:
+ rc = GC_INVALID_CIPHER;
+ }
+ break;
+#endif
+
+#ifdef GNULIB_GC_ARCFOUR
+ case GC_ARCFOUR128:
+ case GC_ARCFOUR40:
+ switch (mode)
+ {
+ case GC_STREAM:
+ break;
+
+ default:
+ rc = GC_INVALID_CIPHER;
+ }
+ break;
+#endif
+
+#ifdef GNULIB_GC_DES
+ case GC_DES:
+ switch (mode)
+ {
+ case GC_ECB:
+ break;
+
+ default:
+ rc = GC_INVALID_CIPHER;
+ }
+ break;
+#endif
+
+#ifdef GNULIB_GC_RIJNDAEL
+ case GC_AES128:
+ case GC_AES192:
+ case GC_AES256:
+ switch (mode)
+ {
+ case GC_ECB:
+ case GC_CBC:
+ break;
+
+ default:
+ rc = GC_INVALID_CIPHER;
+ }
+ break;
+#endif
+
+ default:
+ rc = GC_INVALID_CIPHER;
+ }
+
+ if (rc == GC_OK)
+ *outhandle = ctx;
+ else
+ free (ctx);
+
+ return rc;
+}
+
+Gc_rc
+gc_cipher_setkey (gc_cipher_handle handle, size_t keylen, const char *key)
+{
+ _gc_cipher_ctx *ctx = handle;
+
+ switch (ctx->alg)
+ {
+#ifdef GNULIB_GC_ARCTWO
+ case GC_ARCTWO40:
+ arctwo_setkey (&ctx->arctwoContext, keylen, key);
+ break;
+#endif
+
+#ifdef GNULIB_GC_ARCFOUR
+ case GC_ARCFOUR128:
+ case GC_ARCFOUR40:
+ arcfour_setkey (&ctx->arcfourContext, key, keylen);
+ break;
+#endif
+
+#ifdef GNULIB_GC_DES
+ case GC_DES:
+ if (keylen != 8)
+ return GC_INVALID_CIPHER;
+ des_setkey (&ctx->desContext, key);
+ break;
+#endif
+
+#ifdef GNULIB_GC_RIJNDAEL
+ case GC_AES128:
+ case GC_AES192:
+ case GC_AES256:
+ {
+ rijndael_rc rc;
+ size_t i;
+ char keyMaterial[RIJNDAEL_MAX_KEY_SIZE + 1];
+
+ for (i = 0; i < keylen; i++)
+ sprintf (&keyMaterial[2*i], "%02x", key[i] & 0xFF);
+
+ rc = rijndaelMakeKey (&ctx->aesEncKey, RIJNDAEL_DIR_ENCRYPT,
+ keylen * 8, keyMaterial);
+ if (rc < 0)
+ return GC_INVALID_CIPHER;
+
+ rc = rijndaelMakeKey (&ctx->aesDecKey, RIJNDAEL_DIR_DECRYPT,
+ keylen * 8, keyMaterial);
+ if (rc < 0)
+ return GC_INVALID_CIPHER;
+
+ rc = rijndaelCipherInit (&ctx->aesContext, RIJNDAEL_MODE_ECB, NULL);
+ if (rc < 0)
+ return GC_INVALID_CIPHER;
+ }
+ break;
+#endif
+
+ default:
+ return GC_INVALID_CIPHER;
+ }
+
+ return GC_OK;
+}
+
+Gc_rc
+gc_cipher_setiv (gc_cipher_handle handle, size_t ivlen, const char *iv)
+{
+ _gc_cipher_ctx *ctx = handle;
+
+ switch (ctx->alg)
+ {
+#ifdef GNULIB_GC_ARCTWO
+ case GC_ARCTWO40:
+ if (ivlen != ARCTWO_BLOCK_SIZE)
+ return GC_INVALID_CIPHER;
+ memcpy (ctx->arctwoIV, iv, ivlen);
+ break;
+#endif
+
+#ifdef GNULIB_GC_RIJNDAEL
+ case GC_AES128:
+ case GC_AES192:
+ case GC_AES256:
+ switch (ctx->mode)
+ {
+ case GC_ECB:
+ /* Doesn't use IV. */
+ break;
+
+ case GC_CBC:
+ {
+ rijndael_rc rc;
+ size_t i;
+ char ivMaterial[2 * RIJNDAEL_MAX_IV_SIZE + 1];
+
+ for (i = 0; i < ivlen; i++)
+ sprintf (&ivMaterial[2*i], "%02x", iv[i] & 0xFF);
+
+ rc = rijndaelCipherInit (&ctx->aesContext, RIJNDAEL_MODE_CBC,
+ ivMaterial);
+ if (rc < 0)
+ return GC_INVALID_CIPHER;
+ }
+ break;
+
+ default:
+ return GC_INVALID_CIPHER;
+ }
+ break;
+#endif
+
+ default:
+ return GC_INVALID_CIPHER;
+ }
+
+ return GC_OK;
+}
+
+Gc_rc
+gc_cipher_encrypt_inline (gc_cipher_handle handle, size_t len, char *data)
+{
+ _gc_cipher_ctx *ctx = handle;
+
+ switch (ctx->alg)
+ {
+#ifdef GNULIB_GC_ARCTWO
+ case GC_ARCTWO40:
+ switch (ctx->mode)
+ {
+ case GC_ECB:
+ arctwo_encrypt (&ctx->arctwoContext, data, data, len);
+ break;
+
+ case GC_CBC:
+ for (; len >= ARCTWO_BLOCK_SIZE; len -= ARCTWO_BLOCK_SIZE,
+ data += ARCTWO_BLOCK_SIZE)
+ {
+ size_t i;
+ for (i = 0; i < ARCTWO_BLOCK_SIZE; i++)
+ data[i] ^= ctx->arctwoIV[i];
+ arctwo_encrypt (&ctx->arctwoContext, data, data,
+ ARCTWO_BLOCK_SIZE);
+ memcpy (ctx->arctwoIV, data, ARCTWO_BLOCK_SIZE);
+ }
+ break;
+
+ default:
+ return GC_INVALID_CIPHER;
+ }
+ break;
+#endif
+
+#ifdef GNULIB_GC_ARCFOUR
+ case GC_ARCFOUR128:
+ case GC_ARCFOUR40:
+ arcfour_stream (&ctx->arcfourContext, data, data, len);
+ break;
+#endif
+
+#ifdef GNULIB_GC_DES
+ case GC_DES:
+ for (; len >= 8; len -= 8, data += 8)
+ des_ecb_encrypt (&ctx->desContext, data, data);
+ break;
+#endif
+
+#ifdef GNULIB_GC_RIJNDAEL
+ case GC_AES128:
+ case GC_AES192:
+ case GC_AES256:
+ {
+ int nblocks;
+
+ nblocks = rijndaelBlockEncrypt (&ctx->aesContext, &ctx->aesEncKey,
+ data, 8 * len, data);
+ if (nblocks < 0)
+ return GC_INVALID_CIPHER;
+ }
+ break;
+#endif
+
+ default:
+ return GC_INVALID_CIPHER;
+ }
+
+ return GC_OK;
+}
+
+Gc_rc
+gc_cipher_decrypt_inline (gc_cipher_handle handle, size_t len, char *data)
+{
+ _gc_cipher_ctx *ctx = handle;
+
+ switch (ctx->alg)
+ {
+#ifdef GNULIB_GC_ARCTWO
+ case GC_ARCTWO40:
+ switch (ctx->mode)
+ {
+ case GC_ECB:
+ arctwo_decrypt (&ctx->arctwoContext, data, data, len);
+ break;
+
+ case GC_CBC:
+ for (; len >= ARCTWO_BLOCK_SIZE; len -= ARCTWO_BLOCK_SIZE,
+ data += ARCTWO_BLOCK_SIZE)
+ {
+ char tmpIV[ARCTWO_BLOCK_SIZE];
+ size_t i;
+ memcpy (tmpIV, data, ARCTWO_BLOCK_SIZE);
+ arctwo_decrypt (&ctx->arctwoContext, data, data,
+ ARCTWO_BLOCK_SIZE);
+ for (i = 0; i < ARCTWO_BLOCK_SIZE; i++)
+ data[i] ^= ctx->arctwoIV[i];
+ memcpy (ctx->arctwoIV, tmpIV, ARCTWO_BLOCK_SIZE);
+ }
+ break;
+
+ default:
+ return GC_INVALID_CIPHER;
+ }
+ break;
+#endif
+
+#ifdef GNULIB_GC_ARCFOUR
+ case GC_ARCFOUR128:
+ case GC_ARCFOUR40:
+ arcfour_stream (&ctx->arcfourContext, data, data, len);
+ break;
+#endif
+
+#ifdef GNULIB_GC_DES
+ case GC_DES:
+ for (; len >= 8; len -= 8, data += 8)
+ des_ecb_decrypt (&ctx->desContext, data, data);
+ break;
+#endif
+
+#ifdef GNULIB_GC_RIJNDAEL
+ case GC_AES128:
+ case GC_AES192:
+ case GC_AES256:
+ {
+ int nblocks;
+
+ nblocks = rijndaelBlockDecrypt (&ctx->aesContext, &ctx->aesDecKey,
+ data, 8 * len, data);
+ if (nblocks < 0)
+ return GC_INVALID_CIPHER;
+ }
+ break;
+#endif
+
+ default:
+ return GC_INVALID_CIPHER;
+ }
+
+ return GC_OK;
+}
+
+Gc_rc
+gc_cipher_close (gc_cipher_handle handle)
+{
+ _gc_cipher_ctx *ctx = handle;
+
+ if (ctx)
+ free (ctx);
+
+ return GC_OK;
+}