arduino uno working bench

templates/uno/configure

 #!/bin/bash
-mv *.c *.h src/
+mv *.c src/
+mv *.h include/

templates/uno/src/crypto_aead.h → templates/uno/include/crypto_aead.h

+#ifdef __cplusplus
+extern "C" {
+#endif
+    
 int crypto_aead_encrypt(
 	unsigned char *c,unsigned long long *clen,
 	const unsigned char *m,unsigned long long mlen,
@@ -17,3 +21,6 @@ int crypto_aead_decrypt(
 	const unsigned char *k
 	); 
 
+#ifdef __cplusplus
+}
+#endif

templates/uno/src/main.ino

 #include "crypto_aead.h"
 #include "api.h"
 
-/*
-  Blink
+#define MAX_BYTES 100
 
-  Turns an LED on for one second, then off for one second, repeatedly.
+#define DEBUG
 
-  Most Arduinos have an on-board LED you can control. On the UNO, MEGA and ZERO
-  it is attached to digital pin 13, on MKR1000 on pin 6. LED_BUILTIN is set to
-  the correct LED pin independent of which board is used.
-  If you want to know what pin the on-board LED is connected to on your Arduino
-  model, check the Technical Specs of your board at:
-  https://www.arduino.cc/en/Main/Products
+uint8_t npub[CRYPTO_NPUBBYTES];
+uint8_t nsec[CRYPTO_NSECBYTES];
+uint8_t k[CRYPTO_KEYBYTES];
+uint8_t ad[MAX_BYTES];
+unsigned long long int adlen;
+uint8_t m[MAX_BYTES];
+unsigned long long int mlen;
+uint8_t c[MAX_BYTES];
+unsigned long long int clen;
 
-  modified 8 May 2014
-  by Scott Fitzgerald
-  modified 2 Sep 2016
-  by Arturo Guadalupi
-  modified 8 Sep 2016
-  by Colby Newman
+void uart_write(uint8_t x) {
+    Serial.write((uint8_t) (x));
+}
+
+uint8_t uart_read() {
+    int r;
+    do {
+        r = Serial.read();
+    } while (r == -1);
+    return (uint8_t) (0xff & r);
+}
+
+// Simple serial protocol with packets and checksum
+const uint8_t AMUX_TAG = 0xf9;
+const uint8_t AMUX_END = 0xf3;
+const uint8_t AMUX_EXT = 0x80;
+
+void uartp_send(const void *src, uint16_t len) {
+    uint8_t len_ind_0, len_ind_1, fcs, info;
+    const uint8_t *buf = (const uint8_t *) src;
+
+    uart_write(AMUX_TAG);
+    len_ind_0 = (uint8_t) (0xff & len);
+    len_ind_1 = (uint8_t) (0xff & (len >> 7));
+    if (len < 128) {
+        uart_write(len_ind_0);
+    } else {
+        uart_write(len_ind_0 | AMUX_EXT);
+        uart_write(len_ind_1);
+    }
+    fcs = 0;
+    for (uint16_t i = 0; i < len; i++) {
+        info = buf[i];
+        fcs += info;
+        uart_write(buf[i]);
+    }
+    fcs = 255 - fcs;
+    uart_write(fcs);
+    uart_write(AMUX_END);
+}
+
+
+uint16_t uartp_recv(void *dst, uint16_t buf_len) {
+    uint8_t *buf = (uint8_t *) dst;
+    uint8_t tag_old, tag, info, cs;
+    uint16_t len;
 
-  This example code is in the public domain.
+    tag = AMUX_END;
+    while (1) {
 
-  http://www.arduino.cc/en/Tutorial/Blink
-*/
+        do {
+            tag_old = tag;
+            tag = uart_read();
+        } while(tag != AMUX_TAG || tag_old != AMUX_END);
+
+        len = (uint16_t) uart_read();
+        if (len & AMUX_EXT) {
+            len &= (~AMUX_EXT);
+            len |= (uint16_t) (uart_read() << 7);
+        }
+        if (len > buf_len) {
+            return len;
+        }
+
+        uint16_t i = 0;
+        cs = 0;
+        for (i = 0; i < len; i++) {
+            info = uart_read();
+            buf[i] = info;
+            cs += info;
+        }
+        cs += uart_read();
+        tag = uart_read();
+        if (0xff == cs) {
+            if (AMUX_END == tag) {
+                return len;
+            }
+        }
+
+    }
+}
+
+#ifdef DEBUG
+#define DEBUG_BUF_LEN 80
+int dbg_printf(const char *format, ...) {
+    char printbuf[DEBUG_BUF_LEN+2];
+
+    va_list vargs;
+    va_start(vargs, format);
+    int r = vsnprintf(printbuf+1, DEBUG_BUF_LEN, format, vargs);
+    va_end(vargs);
+
+    if (r < 0) {
+        memcpy(printbuf+1, "DEBUG ERROR\r\n", 13);
+        r = 13;
+    }
+
+    r = r > DEBUG_BUF_LEN ? DEBUG_BUF_LEN : r;
+    printbuf[0] = 0xde;  // Debug messages should start with "\xde"
+    uartp_send(printbuf, r+1);
+    return r;
+}
+#else
+  #define dbg_printf(...) (0)
+#endif
+
+void assert(bool b) {
+    if (b)
+        return;
+    dbg_printf("Assertion failed\r\n");
+    for(;;)
+        yield();
+}
 
-// the setup function runs once when you press reset or power the board
 void setup() {
-  // initialize digital pin LED_BUILTIN as an output.
+    Serial.begin(115200);
     pinMode(LED_BUILTIN, OUTPUT);
+    digitalWrite(LED_BUILTIN, HIGH);
+    delay(100);
+    Serial.println("Hello, World!");
 }
 
-// the loop function runs over and over again forever
+
 void loop() {
-  digitalWrite(LED_BUILTIN, HIGH);   // turn the LED on (HIGH is the voltage level)
-  delay(1000);                       // wait for a second
-  digitalWrite(LED_BUILTIN, LOW);    // turn the LED off by making the voltage LOW
-  delay(1000);                       // wait for a second
+    static uint8_t buf[256];
+    int res;
+    uint16_t len = uartp_recv(buf, 255);
+    uint8_t action = buf[0];
+    if (len == 0 || len > 255)
+        return;
+
+    dbg_printf("Received command %c\r\n", action);
+    uint16_t l = len - 1;
+    uint8_t *var = buf+1;
+    switch (action) {
+        case 'm': assert(l <= MAX_BYTES);        memcpy(m,    var, l); mlen = l; break;
+        case 'c': assert(l <= MAX_BYTES);        memcpy(c,    var, l); clen = l; break;
+        case 'a': assert(l <= MAX_BYTES);        memcpy(ad,   var, l); adlen = l; break;
+        case 'k': assert(l == CRYPTO_KEYBYTES);  memcpy(k,    var, l); break;
+        case 'p': assert(l == CRYPTO_NPUBBYTES); memcpy(npub, var, l); break;
+        case 's': assert(l == CRYPTO_NSECBYTES); memcpy(nsec, var, l); break;
+        case 'e':
+            digitalWrite(LED_BUILTIN, LOW);
+            res = crypto_aead_encrypt(c, &clen, m, mlen, ad, adlen, nsec, npub, k);
+            digitalWrite(LED_BUILTIN, HIGH);
+            break;
+        case 'd':
+            digitalWrite(LED_BUILTIN, LOW);
+            res = crypto_aead_decrypt(m, &mlen, nsec, c, clen, ad, adlen, npub, k);
+            digitalWrite(LED_BUILTIN, HIGH);
+            break;
+    }
+
+    switch (action) {
+        case'a': case'c': case'k': case'm': case'p': case's':
+        case'd': case'e':
+            l = 0;
+            break;
+        case'M': var = m;    l = mlen; break;
+        case'C': var = c;    l = clen; break;
+        case'A': var = ad;   l = adlen; break;
+        case'K': var = k;    l = CRYPTO_KEYBYTES; break;
+        case'P': var = npub; l = CRYPTO_NPUBBYTES; break;
+        case'S': var = nsec; l = CRYPTO_NSECBYTES; break;
+    }
+    buf[0] = action;
+    memcpy(buf+1, var, l);
+    uartp_send(buf, l+1);
 }

templates/uno/test

@@ -2,8 +2,13 @@
 
 import os
 import sys
+import struct
+import serial
 import subprocess
 
+def eprint(*args, **kargs):
+    print(*args, file=sys.stderr, **kargs)
+
 
 def flash():
     pipe = subprocess.PIPE
@@ -11,13 +16,144 @@ def flash():
             stdout=sys.stderr, stdin=pipe)
     stdout, stderr = p.communicate("") 
 
+def get_serial():
+    import serial.tools.list_ports
+    ports = serial.tools.list_ports.comports()
+    devices = [ p.device for p in ports ]
+    devices.sort()
+    return devices[-1]
+
 def main(argv):
-    print(argv[0], file=sys.stderr)
+    eprint(argv[0])
     script_dir = os.path.split(argv[0])[0]
     if len(script_dir) > 0:
         os.chdir(script_dir)
     flash()
-    return 0;
+
+    dev = get_serial()
+    ser = serial.Serial(dev, baudrate=115200, timeout=5)
+
+    def uart_read():
+        r = ser.read(1)
+        if len(r) != 1:
+            raise Exception("Serial read error")
+        return r[0]
+
+    def uart_write(c):
+        b = struct.pack("B", c)
+        r = ser.write(b)
+        if r != len(b):
+            raise Exception("Serial write error")
+        return r
+
+    def uart_recvframe():
+        while 1:
+            tag_old = 0
+            tag = 0xf3
+            while tag_old != 0xf3 or tag != 0xf9:
+                tag_old = tag
+                tag = uart_read()
+            tag_old = tag
+            
+            l = uart_read()
+            if l & 0x80:
+                l &= 0x7f
+                l |= uart_read() << 7
+
+            fcs = 0
+            buf = []
+            for i in range(l):
+                info = uart_read()
+                buf.append(info)
+                fcs = (fcs + info) & 0xff
+            fcs = (fcs + uart_read()) & 0xff
+
+            tag = uart_read()
+            if fcs == 0xff:
+                if tag == 0xf3:
+                    buf = bytes(buf)
+                    if len(buf) >= 1 and buf[0] == 0xde:
+                        sys.stderr.buffer.write(buf[1:])
+                        sys.stderr.flush()
+                    else:
+                        return buf
+
+    def uart_sendframe(buf):
+        uart_write(0xf9)
+        len_ind_0 = 0xff & len(buf)
+        len_ind_1 = 0xff & (len(buf) >> 7)
+        if len(buf) < 128:
+            uart_write(len_ind_0)
+        else:
+            uart_write(len_ind_0 | 0x80)
+            uart_write(len_ind_1)
+        fcs = 0
+        for i in range(len(buf)):
+            info = buf[i]
+            fcs = (fcs + info) & 0xff
+            uart_write(buf[i])
+        fcs = (0xff - fcs) & 0xff
+        uart_write(fcs)
+        uart_write(0xf3)
+
+    def stdin_read(n):
+        b = sys.stdin.buffer.read(n)
+        if len(b) != n:
+            sys.exit(1)
+        return b
+
+    def stdin_readvar():
+        l = stdin_read(4)
+        (l, ) = struct.unpack("<I", l)
+        v = stdin_read(l)
+        return v
+
+    exp_hello = b"Hello, World!"
+    hello = ser.read(len(exp_hello))
+    if hello != exp_hello:
+        eprint("Improper board initialization message: ")
+        return 1
+    eprint("Board initialized properly")
+    sys.stdout.write("Hello, World!\n")
+    sys.stdout.flush()
+
+    while 1:
+        action = stdin_read(1)[0]
+        eprint("Command %c from stdin" % action)
+
+        if action in b"ackmps":
+            v = stdin_readvar()
+            uart_sendframe(struct.pack("B", action) + v)
+            ack = uart_recvframe()
+            if len(ack) != 1 or ack[0] != action:
+                raise Exception("Unacknowledged variable transfer")
+            eprint("Var %c successfully sent to board" % action)
+
+        elif action in b"ACKMPS":
+            c = struct.pack("B", action)
+            uart_sendframe(c)
+            v = uart_recvframe()
+            if len(v) < 1 or v[0] != action:
+                raise Exception("Could not obtain variable from board")
+            v = v[1:]
+            eprint("Var %c received from board: %s" % (action, v.hex()))
+            l = struct.pack("<I", len(v))
+            sys.stdout.buffer.write(l + v)
+            sys.stdout.flush()
+
+        elif action in b"ed":
+            c = struct.pack("B", action)
+            uart_sendframe(c)
+            ack = uart_recvframe()
+            if len(ack) != 1 or ack[0] != action:
+                raise Exception("Unacknowledged variable transfer")
+            eprint("Operation %c completed successfully" % action)
+
+        else:
+            raise Exception("Unknown action %c" % action)
+        
+    
+    return 0
 
 
 if __name__ == "__main__":

test.py

@@ -42,6 +42,7 @@ def main(argv):
 
     if read(14) != b"Hello, World!\n":
         raise Exception("Unexpected output")
+    print("Ready")
 
     m = b""
     ad = b""