Adding first release of Pico CCID. It should be the core for different types of smart cards.

src/rng/neug.c

@@ -0,0 +1,182 @@
+/* 
+ * This file is part of the Pico CCID distribution (https://github.com/polhenarejos/pico-ccid).
+ * Copyright (c) 2022 Pol Henarejos.
+ * 
+ * This program is free software: you can redistribute it and/or modify  
+ * it under the terms of the GNU General Public License as published by  
+ * the Free Software Foundation, version 3.
+ *
+ * This program is distributed in the hope that it will be useful, but 
+ * WITHOUT ANY WARRANTY; without even the implied warranty of 
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License 
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+ 
+//Part of the code is taken from GnuK (GPLv3)
+
+
+#include <stdint.h>
+#include <string.h>
+#include <stdio.h>
+#include "pico/stdlib.h"
+
+#include "neug.h"
+#include "hardware/structs/rosc.h"
+#include "hardware/gpio.h"
+#include "hardware/adc.h"
+#include "bsp/board.h"
+#include "pico/unique_id.h"
+
+void adc_start() {
+    adc_init();
+    adc_gpio_init(27);
+    adc_select_input(1);
+}
+
+void adc_stop() {
+}
+
+static uint64_t random_word = 0xcbf29ce484222325;
+static uint8_t ep_round = 0;
+
+static void ep_init() {
+    random_word = 0xcbf29ce484222325;
+    ep_round = 0;
+}
+
+/* Here, we assume a little endian architecture.  */
+static int ep_process () {
+    if (ep_round == 0) {
+        ep_init();
+    }
+    uint64_t word = 0x0;
+    for (int n = 0; n < 64; n++) {
+        uint8_t bit1, bit2;
+        do
+        {
+            bit1 = rosc_hw->randombit&0xff;
+            //sleep_ms(1);
+            bit2 = rosc_hw->randombit&0xff;
+        } while(bit1 == bit2);
+        word = (word << 1) | bit1;
+    }
+    random_word ^= word^board_millis()^adc_read();
+    random_word *= 0x00000100000001B3;
+    if (++ep_round == 8) {
+        ep_round = 0;
+        return 2; //2 words 
+    }
+    return 0;
+}
+
+static const uint32_t *ep_output() {
+    return (uint32_t *)&random_word;
+}
+
+struct rng_rb {
+    uint32_t *buf;
+    uint8_t head, tail;
+    uint8_t size;
+    unsigned int full :1;
+    unsigned int empty :1;
+};
+
+static void rb_init(struct rng_rb *rb, uint32_t *p, uint8_t size) {
+    rb->buf = p;
+    rb->size = size;
+    rb->head = rb->tail = 0;
+    rb->full = 0;
+    rb->empty = 1;
+}
+
+static void rb_add(struct rng_rb *rb, uint32_t v) {
+    rb->buf[rb->tail++] = v;
+    if (rb->tail == rb->size)
+        rb->tail = 0;
+    if (rb->tail == rb->head)
+        rb->full = 1;
+    rb->empty = 0;
+}
+
+static uint32_t rb_del(struct rng_rb *rb) {
+    uint32_t v = rb->buf[rb->head++];
+
+    if (rb->head == rb->size)
+        rb->head = 0;
+    if (rb->head == rb->tail)
+        rb->empty = 1;
+    rb->full = 0;
+
+    return v;
+}
+
+static struct rng_rb the_ring_buffer;
+
+void *neug_task() {
+    struct rng_rb *rb = &the_ring_buffer;
+ 
+    int n;
+
+    if ((n = ep_process())) {
+	    int i;
+	    const uint32_t *vp;
+
+	    vp = ep_output();
+
+	    for (i = 0; i < n; i++) {
+	        rb_add (rb, *vp++);
+	        if (rb->full)
+		        break;
+	    }
+	}
+
+    return NULL;
+}
+
+void neug_init(uint32_t *buf, uint8_t size) {
+    pico_unique_board_id_t unique_id;
+    pico_get_unique_board_id(&unique_id);
+    const uint32_t *u = (const uint32_t *)unique_id.id;
+    struct rng_rb *rb = &the_ring_buffer;
+    int i;
+
+    rb_init(rb, buf, size);
+    
+    adc_start();
+    
+    ep_init();
+}
+
+void neug_flush(void) {
+    struct rng_rb *rb = &the_ring_buffer;
+    
+    while (!rb->empty)
+        rb_del (rb);
+}
+
+uint32_t neug_get(int kick) {
+    struct rng_rb *rb = &the_ring_buffer;
+    uint32_t v;
+
+    while (rb->empty)
+        neug_task();
+    v = rb_del(rb);
+
+    return v;
+}
+
+void neug_wait_full(void) { //should be called only on core1
+    struct rng_rb *rb = &the_ring_buffer;
+
+    while (!rb->full) {
+        sleep_ms(1);
+    }
+}
+
+void neug_fini(void) {
+    neug_get(1);
+}
+

src/rng/neug.h

@@ -0,0 +1,29 @@
+/* 
+ * This file is part of the Pico CCID distribution (https://github.com/polhenarejos/pico-ccid).
+ * Copyright (c) 2022 Pol Henarejos.
+ * 
+ * This program is free software: you can redistribute it and/or modify  
+ * it under the terms of the GNU General Public License as published by  
+ * the Free Software Foundation, version 3.
+ *
+ * This program is distributed in the hope that it will be useful, but 
+ * WITHOUT ANY WARRANTY; without even the implied warranty of 
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License 
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _NEUG_H_
+#define _NEUG_H_
+
+#define NEUG_PRE_LOOP 32
+
+void neug_init(uint32_t *buf, uint8_t size);
+uint32_t neug_get();
+void neug_flush(void);
+void neug_wait_full(void);
+void neug_fini(void);
+
+#endif

src/rng/random.c

@@ -0,0 +1,109 @@
+/* 
+ * This file is part of the Pico CCID distribution (https://github.com/polhenarejos/pico-ccid).
+ * Copyright (c) 2022 Pol Henarejos.
+ * 
+ * This program is free software: you can redistribute it and/or modify  
+ * it under the terms of the GNU General Public License as published by  
+ * the Free Software Foundation, version 3.
+ *
+ * This program is distributed in the hope that it will be useful, but 
+ * WITHOUT ANY WARRANTY; without even the implied warranty of 
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License 
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+#include <stdint.h>
+#include <string.h>
+
+#include "neug.h"
+
+#define RANDOM_BYTES_LENGTH 32
+static uint32_t random_word[RANDOM_BYTES_LENGTH/sizeof (uint32_t)];
+
+void random_init(void) {
+    int i;
+
+    neug_init(random_word, RANDOM_BYTES_LENGTH/sizeof (uint32_t));
+
+    for (i = 0; i < NEUG_PRE_LOOP; i++)
+        neug_get();
+}
+
+void random_fini(void) {
+    neug_fini ();
+}
+
+/*
+ * Return pointer to random 32-byte
+ */
+void random_bytes_free (const uint8_t *p);
+#define MAX_RANDOM_BUFFER 1024
+const uint8_t * random_bytes_get(size_t len) {
+    if (len > MAX_RANDOM_BUFFER)
+        return NULL;
+    static uint32_t return_word[MAX_RANDOM_BUFFER/sizeof(uint32_t)];
+    for (int ix = 0; ix < len; ix += RANDOM_BYTES_LENGTH) {
+        neug_wait_full();
+        memcpy(return_word+ix/sizeof(uint32_t), random_word, RANDOM_BYTES_LENGTH);
+        random_bytes_free((const uint8_t *)random_word);
+    }
+    return (const uint8_t *)return_word;
+}
+
+/*
+ * Free pointer to random 32-byte
+ */
+void random_bytes_free(const uint8_t *p) {
+    (void)p;
+    memset(random_word, 0, RANDOM_BYTES_LENGTH);
+    neug_flush();
+}
+
+/*
+ * Return 4-byte salt
+ */
+void random_get_salt(uint8_t *p) {
+    uint32_t rnd;
+
+    rnd = neug_get();
+    memcpy(p, &rnd, sizeof (uint32_t));
+    rnd = neug_get();
+    memcpy(p + sizeof (uint32_t), &rnd, sizeof (uint32_t));
+}
+
+
+/*
+ * Random byte iterator
+ */
+int random_gen(void *arg, unsigned char *out, size_t out_len) {
+    uint8_t *index_p = (uint8_t *)arg;
+    uint8_t index = index_p ? *index_p : 0;
+    size_t n;
+
+    while (out_len) {
+        neug_wait_full();
+
+        n = RANDOM_BYTES_LENGTH - index;
+        if (n > out_len)
+	        n = out_len;
+
+        memcpy(out, ((unsigned char *)random_word) + index, n);
+        out += n;
+        out_len -= n;
+        index += n;
+
+        if (index >= RANDOM_BYTES_LENGTH) {
+	        index = 0;
+	        neug_flush();
+	    }
+    }
+
+    if (index_p)
+        *index_p = index;
+
+    return 0;
+}

src/rng/random.h

@@ -0,0 +1,38 @@
+/* 
+ * This file is part of the Pico CCID distribution (https://github.com/polhenarejos/pico-ccid).
+ * Copyright (c) 2022 Pol Henarejos.
+ * 
+ * This program is free software: you can redistribute it and/or modify  
+ * it under the terms of the GNU General Public License as published by  
+ * the Free Software Foundation, version 3.
+ *
+ * This program is distributed in the hope that it will be useful, but 
+ * WITHOUT ANY WARRANTY; without even the implied warranty of 
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License 
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+#ifndef _RANDOM_H_
+#define _RANDOM_H_
+
+#include "stdlib.h"
+#include "pico/stdlib.h"
+
+void random_init (void);
+void random_fini (void);
+
+/* 32-byte random bytes */
+const uint8_t *random_bytes_get (size_t);
+void random_bytes_free (const uint8_t *p);
+
+/* 8-byte salt */
+void random_get_salt (uint8_t *p);
+
+/* iterator returning a byta at a time */
+int random_gen (void *arg, unsigned char *output, size_t output_len);
+
+#endif