google-ipmi-sys: initial commit: OEM IPMI handler
This implements a set of OEM IPMI commands built as sub-commands under
one OEM IPMI command registered in the Google OEM Namespace.
Change-Id: I65ff6f35838b501ac6ac67f7765bbc474b808660
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/cpld.cpp b/cpld.cpp
new file mode 100644
index 0000000..6194278
--- /dev/null
+++ b/cpld.cpp
@@ -0,0 +1,125 @@
+/*
+ * Copyright 2018 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "cpld.hpp"
+
+#include "main.hpp"
+
+#include <experimental/filesystem>
+#include <fstream>
+#include <sstream>
+
+namespace google
+{
+namespace ipmi
+{
+namespace fs = std::experimental::filesystem;
+
+struct CpldRequest
+{
+ uint8_t subcommand;
+ uint8_t id;
+} __attribute__((packed));
+
+struct CpldReply
+{
+ uint8_t subcommand;
+ uint8_t major;
+ uint8_t minor;
+ uint8_t point;
+ uint8_t subpoint;
+} __attribute__((packed));
+
+//
+// Handle reading the cpld version from the tmpfs.
+//
+ipmi_ret_t CpldVersion(const uint8_t* reqBuf, uint8_t* replyBuf,
+ size_t* dataLen)
+{
+ if ((*dataLen) < sizeof(struct CpldRequest))
+ {
+ fprintf(stderr, "Invalid command length: %lu\n", (*dataLen));
+ return IPMI_CC_INVALID;
+ }
+
+ // reqBuf[0] is the subcommand.
+ // reqBuf[1] is the CPLD id. "/run/cpld{id}.version" is what we read.
+ // Verified that this cast actually returns the value 255 and not something
+ // negative in the case where reqBuf[1] is 0xff. However, it looks weird
+ // since I would expect int(uint8(0xff)) to be -1. So, just cast it
+ // unsigned. we're casting to an int width to avoid it thinking it's a
+ // letter, because it does that.
+
+ const auto request =
+ reinterpret_cast<const struct CpldRequest*>(&reqBuf[0]);
+
+ std::ostringstream opath;
+ opath << "/run/cpld" << static_cast<unsigned int>(request->id)
+ << ".version";
+ // Check for file
+
+ std::error_code ec;
+ if (!fs::exists(opath.str(), ec))
+ {
+ fprintf(stderr, "Path: '%s' doesn't exist.\n", opath.str().c_str());
+ return IPMI_CC_INVALID;
+ }
+ // We're uninterested in the state of ec.
+
+ // If file exists, read.
+ std::ifstream ifs;
+ ifs.exceptions(std::ifstream::failbit);
+ std::string value;
+ try
+ {
+ ifs.open(opath.str());
+ ifs >> value;
+ }
+ catch (std::ios_base::failure& fail)
+ {
+ return IPMI_CC_INVALID;
+ }
+
+ // If value parses as expected, return version.
+ int major = 0;
+ int minor = 0;
+ int point = 0;
+ int subpoint = 0;
+
+ int num_fields =
+ sscanf(value.c_str(), "%d.%d.%d.%d", &major, &minor, &point, &subpoint);
+ if (num_fields == 0)
+ {
+ fprintf(stderr, "Invalid version.\n");
+ return IPMI_CC_INVALID;
+ }
+
+ // Truncate if the version is too high (documented).
+ struct CpldReply reply;
+ reply.subcommand = SysCpldVersion;
+ reply.major = static_cast<uint8_t>(major);
+ reply.minor = static_cast<uint8_t>(minor);
+ reply.point = static_cast<uint8_t>(point);
+ reply.subpoint = static_cast<uint8_t>(subpoint);
+
+ memcpy(&replyBuf[0], &reply, sizeof(struct CpldReply));
+ (*dataLen) = sizeof(struct CpldReply);
+
+ return IPMI_CC_OK;
+}
+
+} // namespace ipmi
+} // namespace google