Rename main.c to hsm.c for consistency and a slightly simpler Makefile.

1 files changed, 226 insertions, 0 deletions

diff --git a/projects/hsm/hsm.c b/projects/hsm/hsm.c
new file mode 100644
index 0000000..79c567b
--- /dev/null
+++ b/projects/hsm/hsm.c
@@ -0,0 +1,226 @@
+/*
+ * rpc_server.c
+ * ------------
+ * Remote procedure call server-side private API implementation.
+ *
+ * Copyright (c) 2016, NORDUnet A/S All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ * - Redistributions of source code must retain the above copyright notice,
+ *   this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ *
+ * - Neither the name of the NORDUnet nor the names of its contributors may
+ *   be used to endorse or promote products derived from this software
+ *   without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+ * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+ * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/*
+ * This is the main RPC server moddule. It creates a new thread to deal
+ * with each request, to prevent a long-running request (e.g. RSA keygen)
+ * from blocking independent requests from other clients. This has a
+ * number of consequences. We can't do a blocking receive in the main
+ * thread, because that prevents the dispatch thread from transmitting the
+ * response (because they both want to lock the UART - see
+ * stm32f4xx_hal_uart.c). So we have to do a non-blocking receive with a
+ * callback routine. But we can't create a thread from the callback
+ * routine, because it's in the context of an ISR, so we raise a semaphore
+ * for the main thread to create the dispatch thread.
+ */
+
+#include <string.h>
+
+#include "cmsis_os.h"
+
+#include "stm-init.h"
+#include "stm-led.h"
+#include "stm-fmc.h"
+#include "stm-uart.h"
+
+/* stm32f4xx_hal_def.h and hal.h both define HAL_OK as an enum value */
+#define HAL_OK HAL_OKAY
+
+#include "hal.h"
+#include "hal_internal.h"
+#include "slip_internal.h"
+#include "xdr_internal.h"
+
+/* RPC buffers. For each active RPC, there will be two - input and output.
+ */
+
+#ifndef NUM_RPC_BUFFER
+/* An arbitrary number, but we don't expect to have more than 8 concurrent
+ * RPC requests.
+ */
+#define NUM_RPC_BUFFER 16
+#endif
+
+#ifndef MAX_PKT_SIZE
+/* Another arbitrary number, more or less driven by the 4096-bit RSA
+ * keygen test.
+ */
+#define MAX_PKT_SIZE 4096
+#endif
+
+/* The thread entry point takes a single void* argument, so we bundle the
+ * packet buffer and length arguments together.
+ */
+typedef struct {
+    size_t len;
+    uint8_t buf[MAX_PKT_SIZE];
+} rpc_buffer_t;
+
+osPoolDef(rpc_buffer_pool, NUM_RPC_BUFFER, rpc_buffer_t);
+osPoolId  rpc_buffer_pool;
+
+static rpc_buffer_t *rpc_buffer_alloc(void)
+{
+    return (rpc_buffer_t *)osPoolCAlloc(rpc_buffer_pool);
+}
+
+/* A mutex to arbitrate concurrent UART transmits, from RPC responses.
+ */
+osMutexId  uart_mutex;
+osMutexDef(uart_mutex);
+
+/* Thread entry point for the RPC request handler.
+ */
+static void dispatch_thread(void const *args)
+{
+    rpc_buffer_t *ibuf = (rpc_buffer_t *)args;
+    rpc_buffer_t *obuf = rpc_buffer_alloc();
+    if (obuf == NULL) {
+        uint8_t buf[8];
+        uint8_t * bufptr = &buf[4];
+        const uint8_t * const limit = buf + sizeof(buf);
+        memcpy(buf, ibuf->buf, 4);
+        hal_xdr_encode_int(&bufptr, limit, HAL_ERROR_ALLOCATION_FAILURE);
+        osMutexWait(uart_mutex, osWaitForever);
+        hal_rpc_sendto(ibuf->buf, sizeof(buf), NULL);
+        osMutexRelease(uart_mutex);
+        osPoolFree(rpc_buffer_pool, ibuf);
+        Error_Handler();
+    }
+    /* copy client ID from request to response */
+    memcpy(obuf->buf, ibuf->buf, 4);
+    obuf->len = sizeof(obuf->buf) - 4;
+    hal_rpc_server_dispatch(ibuf->buf + 4, ibuf->len - 4, obuf->buf + 4, &obuf->len);
+    osPoolFree(rpc_buffer_pool, ibuf);
+    osMutexWait(uart_mutex, osWaitForever);
+    hal_error_t ret = hal_rpc_sendto(obuf->buf, obuf->len + 4, NULL);
+    osMutexRelease(uart_mutex);
+    osPoolFree(rpc_buffer_pool, obuf);
+    if (ret != HAL_OK)
+        Error_Handler();
+}
+osThreadDef(dispatch_thread, osPriorityNormal, DEFAULT_STACK_SIZE);
+
+/* Semaphore to inform the main thread that there's a new RPC request.
+ */
+osSemaphoreId rpc_sem;
+osSemaphoreDef(rpc_sem);
+
+static uint8_t c;		/* current character received from UART */
+static rpc_buffer_t *ibuf;	/* current RPC input buffer */
+
+/* Callback for HAL_UART_Receive_IT().
+ */
+void HAL_UART2_RxCpltCallback(UART_HandleTypeDef *huart)
+{
+    int complete;
+    hal_slip_recv_char(ibuf->buf, &ibuf->len, sizeof(ibuf->buf), &complete);
+    if (complete)
+	osSemaphoreRelease(rpc_sem);
+
+    HAL_UART_Receive_IT(huart, &c, 1);
+}
+
+hal_error_t hal_serial_send_char(uint8_t c)
+{
+    return (uart_send_char(c) == 0) ? HAL_OK : HAL_ERROR_RPC_TRANSPORT;
+}
+
+hal_error_t hal_serial_recv_char(uint8_t *cp)
+{
+    /* return the character from HAL_UART_Receive_IT */
+    *cp = c;
+    return HAL_OK;
+}
+
+/* The main thread. After the system setup, it waits for the RPC-request
+ * semaphore from HAL_UART_RxCpltCallback, and spawns a dispatch thread.
+ */
+int main()
+{
+    stm_init();
+
+#ifdef TARGET_CRYPTECH_DEV_BRIDGE
+    /* Wait six seconds to not upset the Novena at boot. */
+    led_on(LED_BLUE);
+    for (int i = 0; i < 12; i++) {
+	osDelay(500);
+	led_toggle(LED_BLUE);
+    }
+    led_off(LED_BLUE);
+#endif
+    led_on(LED_GREEN);
+    /* Prepare FMC interface. */
+    fmc_init();
+
+    /* Haaaack. probe_cores() calls malloc(), which works from the main
+     * thread, but not from a spawned thread. It would be better to
+     * rewrite it to use static memory, but for now, just force it to
+     * probe early.
+     */
+    hal_core_iterate(NULL);
+
+    rpc_buffer_pool = osPoolCreate(osPool(rpc_buffer_pool));
+    uart_mutex = osMutexCreate(osMutex(uart_mutex));
+    rpc_sem = osSemaphoreCreate(osSemaphore(rpc_sem), 0);
+
+#ifdef TARGET_CRYPTECH_ALPHA
+    /* Launch other threads:
+     * - admin thread on USART1
+     * - csprng warm-up thread?
+     */
+#endif
+
+    if (hal_rpc_server_init() != HAL_OK)
+	Error_Handler();
+
+    ibuf = rpc_buffer_alloc();
+    if (ibuf == NULL)
+        /* Something is badly wrong. */
+        Error_Handler();
+
+    /* Start the non-blocking receive */
+    HAL_UART_Receive_IT(&huart_user, &c, 1);
+
+    while (1) {
+        osSemaphoreWait(rpc_sem, osWaitForever);
+        if (osThreadCreate(osThread(dispatch_thread), (void *)ibuf) == NULL)
+            Error_Handler();
+        while ((ibuf = rpc_buffer_alloc()) == NULL);
+        /* XXX There's a potential race condition, where another request
+         * could write into the old ibuf, or into the null pointer if
+         * we're out of ibufs.
+         */
+    }
+}