bmc: add network bridge support

This data handler listens on a TCP port for the image bytes.

Signed-off-by: Benjamin Fair <benjaminfair@google.com>
Change-Id: I388fdd7303c5f8bc93a8f75e97b3abf8adbb81af
diff --git a/README.md b/README.md
index 954f7bd..204e039 100644
--- a/README.md
+++ b/README.md
@@ -66,7 +66,7 @@
  Parameter  | Options  | Meaning
 ----------- | -------- | -------
 `command`   | `update` | The tool should try to update the BMC firmware.
-`interface` | `ipmibt`, `ipmilpc`, `ipmipci` | The data transport mechanism, typically `ipmilpc`
+`interface` | `ipmibt`, `ipmilpc`, `ipmipci`, `ipminet` | The data transport mechanism, typically `ipmilpc`
 `image`     | path     | The BMC firmware image file (or tarball)
 `sig`       | path     | The path to a signature file to send to the BMC along with the image file.
 `type`      | blob ending | The ending of the blob id.  For instance `/flash/image` becomes a type of `image`.
@@ -75,12 +75,17 @@
 parameters: `address` and `length`.  These values indicate where on the host
 you've reserved memory to be used for the transfer window.
 
+If you're using a net data transfer mechanism, you'll also need two additional
+parameters: `hostname` and `port`. These specify which address and port the tool
+should attempt to connect to the BMC using.
+
 ## Introduction
 
-This supports two methods of providing the image to stage. You can send the
+This supports three methods of providing the image to stage. You can send the
 file over IPMI packets, which is a very slow process. A 32-MiB image can take
-~3 hours to send via this method.  This can be done in <1 minutes via the PCI
-bridge, or just a few minutes via LPC depending on the size of the mapped area.
+~3 hours to send via this method.  This can be done in <1 minutes via the PCI or
+net bridge, or just a few minutes via LPC depending on the size of the mapped
+area.
 
 This is implemented as a phosphor blob handler.
 
@@ -130,13 +135,15 @@
 The following are configuration options for how the host and BMC are meant to
 transfer the data.  By default, the data-in-IPMI mechanism is enabled.
 
-There are two configurable data transport mechanisms, either staging the bytes
-via the LPC memory region, or the PCI-to-AHB memory region.  Because there is
-only one `MAPPED_ADDRESS` variable at present, a platform should only configure
-one.  The platform's device-tree may have the region locked to a specific
-driver (lpc-aspeed-ctrl), preventing the region from other use.
+There are three configurable data transport mechanisms, either staging the bytes
+via the LPC memory region, the PCI-to-AHB memory region, or sending over a
+network connection.  Because there is only one `MAPPED_ADDRESS` variable at
+present, a platform should not configure LPC and P2A at the same time.  The
+platform's device-tree may have the region locked to a specific driver
+(lpc-aspeed-ctrl), preventing the region from other use.
 
-***NOTE:*** It will likely be possible to configure both in the near future.
+***NOTE:*** It will likely be possible to configure both LPC and P2A in the near
+future.
 
 Variable              | Default | Meaning
 --------------------- | ------- | -------
@@ -159,6 +166,15 @@
 `--enable-aspeed-lpc`  | Use with ASPEED parts.
 `--enable-nuvoton-lpc` | Use with Nuvoton parts.
 
+A platform may also enable the network transport mechanism.
+
+NOTE: This mechanism is only intended to be used in-band and not exposed
+externally, as it doesn't implement any encryption or integrity verification.
+
+Option                | Meaning
+----------------------| -------
+`--enable-net-bridge` | Enable net transport bridge
+
 There are also options to control an optional clean up mechanism.
 
 Option                    | Meaning
diff --git a/bmc/Makefile.am b/bmc/Makefile.am
index 0f9b2fb..63c90b4 100644
--- a/bmc/Makefile.am
+++ b/bmc/Makefile.am
@@ -67,6 +67,10 @@
 libfirmwareblob_common_la_SOURCES += pci_nuvoton_handler.cpp
 endif
 
+if ENABLE_NET_BRIDGE
+libfirmwareblob_common_la_SOURCES += net_handler.cpp
+endif
+
 libfirmwareblob_common_la_CXXFLAGS = \
 	-I$(top_srcdir) \
 	$(SDBUSPLUS_CFLAGS) \
diff --git a/bmc/main.cpp b/bmc/main.cpp
index bc25ff0..0e779b4 100644
--- a/bmc/main.cpp
+++ b/bmc/main.cpp
@@ -25,6 +25,7 @@
 #include "lpc_aspeed.hpp"
 #include "lpc_handler.hpp"
 #include "lpc_nuvoton.hpp"
+#include "net_handler.hpp"
 #include "pci_handler.hpp"
 #include "status.hpp"
 #include "util.hpp"
@@ -71,6 +72,10 @@
 PciDataHandler pciDataHandler(MAPPED_ADDRESS, memoryRegionSize);
 #endif
 
+#ifdef ENABLE_NET_BRIDGE
+NetDataHandler netDataHandler;
+#endif
+
 std::vector<DataHandlerPack> supportedTransports = {
     {FirmwareFlags::UpdateFlags::ipmi, nullptr},
 #ifdef ENABLE_PCI_BRIDGE
@@ -79,6 +84,9 @@
 #ifdef ENABLE_LPC_BRIDGE
     {FirmwareFlags::UpdateFlags::lpc, &lpcDataHandler},
 #endif
+#ifdef ENABLE_NET_BRIDGE
+    {FirmwareFlags::UpdateFlags::net, &netDataHandler},
+#endif
 };
 
 /**
diff --git a/bmc/net_handler.cpp b/bmc/net_handler.cpp
new file mode 100644
index 0000000..14ae4fb
--- /dev/null
+++ b/bmc/net_handler.cpp
@@ -0,0 +1,153 @@
+/*
+ * Copyright 2019 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 "net_handler.hpp"
+
+#include <errno.h>
+#include <netinet/in.h>
+#include <poll.h>
+#include <sys/socket.h>
+#include <unistd.h>
+
+#include <cstdio>
+
+namespace ipmi_flash
+{
+
+bool NetDataHandler::open()
+{
+    listenFd.reset(::socket(AF_INET6, SOCK_STREAM, 0));
+    if (*listenFd < 0)
+    {
+        std::perror("Failed to create socket");
+        (void)listenFd.release();
+        return false;
+    }
+
+    struct sockaddr_in6 listenAddr;
+    listenAddr.sin6_family = AF_INET6;
+    listenAddr.sin6_port = htons(listenPort);
+    listenAddr.sin6_flowinfo = 0;
+    listenAddr.sin6_addr = in6addr_any;
+    listenAddr.sin6_scope_id = 0;
+
+    if (::bind(*listenFd, (struct sockaddr*)&listenAddr, sizeof(listenAddr)) <
+        0)
+    {
+        std::perror("Failed to bind");
+        return false;
+    }
+
+    if (::listen(*listenFd, 1) < 0)
+    {
+        std::perror("Failed to listen");
+        return false;
+    }
+    return true;
+}
+
+bool NetDataHandler::close()
+{
+    connFd.reset();
+    listenFd.reset();
+
+    return true;
+}
+
+std::vector<std::uint8_t> NetDataHandler::copyFrom(std::uint32_t length)
+{
+    if (!connFd)
+    {
+        struct pollfd fds;
+        fds.fd = *listenFd;
+        fds.events = POLLIN;
+
+        int ret = ::poll(&fds, 1, timeoutS * 1000);
+        if (ret < 0)
+        {
+            std::perror("Failed to poll");
+            return std::vector<uint8_t>();
+        }
+        else if (ret == 0)
+        {
+            fprintf(stderr, "Timed out waiting for connection\n");
+            return std::vector<uint8_t>();
+        }
+        else if (fds.revents != POLLIN)
+        {
+            fprintf(stderr, "Invalid poll state: 0x%x\n", fds.revents);
+            return std::vector<uint8_t>();
+        }
+
+        connFd.reset(::accept(*listenFd, nullptr, nullptr));
+        if (*connFd < 0)
+        {
+            std::perror("Failed to accept connection");
+            (void)connFd.release();
+            return std::vector<uint8_t>();
+        }
+
+        struct timeval tv = {};
+        tv.tv_sec = timeoutS;
+        if (setsockopt(*connFd, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv)) < 0)
+        {
+            std::perror("Failed to set receive timeout");
+            return std::vector<uint8_t>();
+        }
+    }
+
+    std::vector<std::uint8_t> data(length);
+
+    std::uint32_t bytesRead = 0;
+    ssize_t ret;
+    do
+    {
+        ret = read(*connFd, data.data() + bytesRead, length - bytesRead);
+        if (ret < 0)
+        {
+            if (errno == EINTR || errno == EAGAIN)
+                continue;
+            std::perror("Failed to read from socket");
+            break;
+        }
+
+        bytesRead += ret;
+    } while (ret > 0 && bytesRead < length);
+
+    if (bytesRead != length)
+    {
+        fprintf(stderr,
+                "Couldn't read full expected amount. Wanted %u but got %u\n",
+                length, bytesRead);
+        data.resize(bytesRead);
+    }
+
+    return data;
+}
+
+bool NetDataHandler::writeMeta(const std::vector<std::uint8_t>& configuration)
+{
+    // TODO: have the host tool send the expected IP address that it will
+    // connect from
+    return true;
+}
+
+std::vector<std::uint8_t> NetDataHandler::readMeta()
+{
+    return std::vector<std::uint8_t>();
+}
+
+} // namespace ipmi_flash
diff --git a/bmc/net_handler.hpp b/bmc/net_handler.hpp
new file mode 100644
index 0000000..0a0943f
--- /dev/null
+++ b/bmc/net_handler.hpp
@@ -0,0 +1,45 @@
+#pragma once
+
+#include "data_handler.hpp"
+
+#include <unistd.h>
+
+#include <cstdint>
+#include <optional>
+#include <stdplus/handle/managed.hpp>
+#include <vector>
+
+namespace ipmi_flash
+{
+
+/**
+ * Data Handler for receiving the image over a network port
+ */
+class NetDataHandler : public DataInterface
+{
+  public:
+    NetDataHandler() : listenFd(std::nullopt), connFd(std::nullopt)
+    {
+    }
+
+    bool open() override;
+    bool close() override;
+    std::vector<std::uint8_t> copyFrom(std::uint32_t length) override;
+    bool writeMeta(const std::vector<std::uint8_t>& configuration) override;
+    std::vector<std::uint8_t> readMeta() override;
+
+    static constexpr std::uint16_t listenPort = 623;
+    static constexpr int timeoutS = 5;
+
+  private:
+    static void closefd(int&& fd)
+    {
+        ::close(fd);
+    }
+    using Fd = stdplus::Managed<int>::Handle<closefd>;
+
+    Fd listenFd;
+    Fd connFd;
+};
+
+} // namespace ipmi_flash
diff --git a/configure.ac b/configure.ac
index bec5108..da2b0a9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -303,6 +303,14 @@
     ])
 ])
 
+AC_ARG_ENABLE([net-bridge],
+    AS_HELP_STRING([--enable-net-bridge],
+                   [Enable external transfers using a TCP connection]))
+AM_CONDITIONAL(ENABLE_NET_BRIDGE, [test "x$enable_net_bridge" = "xyes"])
+AS_IF([test "x$enable_net_bridge" = "xyes"], [
+    AX_APPEND_COMPILE_FLAGS([-DENABLE_NET_BRIDGE], [CXXFLAGS])
+])
+
 AC_ARG_VAR(
     STATIC_HANDLER_STAGED_NAME,
     [The file to use for staging the firmware update.]
diff --git a/flags.hpp b/flags.hpp
index d7c89d5..2aca24c 100644
--- a/flags.hpp
+++ b/flags.hpp
@@ -15,6 +15,9 @@
         ipmi = (1 << 8), /* Expect to send contents over IPMI BlockTransfer. */
         p2a = (1 << 9),  /* Expect to send contents over P2A bridge. */
         lpc = (1 << 10), /* Expect to send contents over LPC bridge. */
+        /* New bridges starting with net densely pack the rest of the bits */
+        net = (1 << 11), /* Expect to send contents over network bridge. */
+        /* nextBridge = (2 << 11) */
     };
 };