fixes bug #467

[enigma2.git] / lib / base / etpm.cpp

diff --git a/lib/base/etpm.cpp b/lib/base/etpm.cpp
new file mode 100644 (file)
index 0000000..f1ac07b
--- /dev/null
+++ b/lib/base/etpm.cpp
@@ -0,0 +1,161 @@
+#include <linux/socket.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/un.h>
+#include <unistd.h>
+#include <openssl/bn.h>
+#include <openssl/sha.h>
+#include <lib/base/etpm.h>
+
+DEFINE_REF(eTPM);
+
+eTPM::eTPM()
+{
+       struct sockaddr_un addr;
+       unsigned char buf[8];
+       unsigned int tag, len;
+       unsigned char *val;
+
+       level2_cert_read = level3_cert_read = false;
+
+       addr.sun_family = AF_UNIX;
+       strcpy(addr.sun_path, TPMD_SOCKET);
+
+       fd = socket(PF_UNIX, SOCK_STREAM, 0);
+       if (fd < 0) {
+               eDebug("[eTPM] socket error");
+               return;
+       }
+
+       if (connect(fd, (const struct sockaddr *)&addr, SUN_LEN(&addr)) < 0) {
+               eDebug("[eTPM] connect error");
+               return;
+       }
+
+       buf[0] = TPMD_DT_LEVEL2_CERT;
+       buf[1] = TPMD_DT_LEVEL3_CERT;
+       if (!send_cmd(TPMD_CMD_GET_DATA, buf, 2))
+       {
+               return;
+       }
+
+       val = (unsigned char*)recv_cmd(&tag, &len);
+       if (val == NULL)
+       {
+               return;
+       }
+
+       parse_data(val, len);
+       free(val);
+}
+
+eTPM::~eTPM()
+{
+
+}
+
+bool eTPM::send_cmd(enum tpmd_cmd cmd, const void *data, unsigned int len)
+{
+       unsigned char buf[len + 4];
+
+       buf[0] = (cmd >> 8) & 0xff;
+       buf[1] = (cmd >> 0) & 0xff;
+       buf[2] = (len >> 8) & 0xff;
+       buf[3] = (len >> 0) & 0xff;
+       memcpy(&buf[4], data, len);
+
+       if (write(fd, buf, sizeof(buf)) != (ssize_t)sizeof(buf)) {
+               fprintf(stderr, "%s: incomplete write\n", __func__);
+               return false;
+       }
+
+       return true;
+}
+
+void* eTPM::recv_cmd(unsigned int *tag, unsigned int *len)
+{
+       unsigned char buf[4];
+       void *val;
+
+       if (read(fd, buf, 4) != 4) {
+               fprintf(stderr, "%s: incomplete read\n", __func__);
+               return NULL;
+       }
+
+       *tag = (buf[0] << 8) | buf[1];
+       *len = (buf[2] << 8) | buf[3];
+
+       val = malloc(*len);
+       if (val == NULL)
+               return NULL;
+
+       if (read(fd, val, *len) != (ssize_t)*len) {
+               fprintf(stderr, "%s: incomplete read\n", __func__);
+               free(val);
+               return NULL;
+       }
+
+       return val;
+}
+
+void eTPM::parse_data(const unsigned char *data, unsigned int datalen)
+{
+       unsigned int i, j;
+       unsigned int tag;
+       unsigned int len;
+       const unsigned char *val;
+
+       for (i = 0; i < datalen; i += len) {
+               tag = data[i++];
+               len = data[i++];
+               val = &data[i];
+
+               switch (tag) {
+               case TPMD_DT_LEVEL2_CERT:
+                       if (len != 210)
+                               break;
+                       memcpy(level2_cert, val, 210);
+                       level2_cert_read = true;
+                       break;
+               case TPMD_DT_LEVEL3_CERT:
+                       if (len != 210)
+                               break;
+                       memcpy(level3_cert, val, 210);
+                       level3_cert_read = true;
+                       break;
+               }
+       }
+}
+
+PyObject *eTPM::getCert(cert_type type)
+{
+       if (type == TPMD_DT_LEVEL2_CERT && level2_cert_read)
+               return PyBuffer_FromMemory(level2_cert, 210);
+       else if (type == TPMD_DT_LEVEL3_CERT && level3_cert_read)
+               return PyBuffer_FromMemory(level3_cert, 210);
+       return Py_None;
+
+}
+
+PyObject *eTPM::challenge(PyObject* rnd)
+{
+       if (PyString_Check(rnd) && PyString_Size(rnd) == 8)
+       {
+               char* buf = PyString_AsString(rnd);
+               if (!send_cmd(TPMD_CMD_COMPUTE_SIGNATURE, buf, 8))
+                       return Py_None;
+
+               unsigned int tag, len;
+               unsigned char *val = (unsigned char*)recv_cmd(&tag, &len);
+
+               if (tag != TPMD_CMD_COMPUTE_SIGNATURE)
+                       return Py_None;
+
+               return PyBuffer_FromMemory(val, len);
+       }
+       else
+               return Py_None;
+}