harden USB telemetry transport

2026-08-17 14:51:12 -04:00
parent 1cf0a9ac77
commit 3c95f3d7be
17 changed files with 709 additions and 114 deletions
@@ -0,0 +1,129 @@
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#include "trikke_transport.h"
+
+typedef struct {
+    trikke_transport_status_t begin_status;
+    trikke_transport_status_t poll_status;
+    unsigned int begin_calls;
+    unsigned int poll_calls;
+    const uint8_t *packet;
+    size_t packet_size;
+} mock_transport_t;
+
+static int fail(int code, const char *message)
+{
+    fprintf(stderr, "transport fixture failure %d: %s\n", code, message);
+    return code;
+}
+
+static trikke_transport_status_t mock_begin(
+    void *context,
+    const uint8_t *packet,
+    size_t packet_size)
+{
+    mock_transport_t *mock = context;
+    ++mock->begin_calls;
+    mock->packet = packet;
+    mock->packet_size = packet_size;
+    return mock->begin_status;
+}
+
+static trikke_transport_status_t mock_poll(void *context)
+{
+    mock_transport_t *mock = context;
+    ++mock->poll_calls;
+    return mock->poll_status;
+}
+
+int main(void)
+{
+    const uint8_t packet[] = {0x54, 0x52, 0x4B, 0x31};
+    mock_transport_t mock = {
+        .begin_status = TRIKKE_TRANSPORT_RETRY,
+        .poll_status = TRIKKE_TRANSPORT_PENDING,
+    };
+    const trikke_transport_t transport = {
+        .context = &mock,
+        .begin = mock_begin,
+        .poll = mock_poll,
+    };
+    trikke_transport_sender_t sender;
+    trikke_transport_sender_init(&sender);
+
+    if (trikke_transport_sender_step(
+            &sender, &transport, packet, sizeof(packet)) !=
+            TRIKKE_TRANSPORT_RETRY ||
+        sender.pending || mock.begin_calls != 1 || mock.poll_calls != 0 ||
+        mock.packet != packet || mock.packet_size != sizeof(packet)) {
+        return fail(1, "zero-accept submission must remain retryable");
+    }
+
+    mock.begin_status = TRIKKE_TRANSPORT_PENDING;
+    if (trikke_transport_sender_step(
+            &sender, &transport, packet, sizeof(packet)) !=
+            TRIKKE_TRANSPORT_PENDING ||
+        !sender.pending || mock.begin_calls != 2 || mock.poll_calls != 0) {
+        return fail(2, "accepted submission must become pending");
+    }
+
+    if (trikke_transport_sender_step(
+            &sender, &transport, packet, sizeof(packet)) !=
+            TRIKKE_TRANSPORT_PENDING ||
+        !sender.pending || mock.begin_calls != 2 || mock.poll_calls != 1) {
+        return fail(3, "pending transfer must poll without resubmission");
+    }
+
+    mock.poll_status = TRIKKE_TRANSPORT_COMPLETE;
+    if (trikke_transport_sender_step(
+            &sender, &transport, packet, sizeof(packet)) !=
+            TRIKKE_TRANSPORT_COMPLETE ||
+        sender.pending || mock.begin_calls != 2 || mock.poll_calls != 2) {
+        return fail(4, "completed transfer must return to idle");
+    }
+
+    mock.begin_status = TRIKKE_TRANSPORT_COMPLETE;
+    if (trikke_transport_sender_step(
+            &sender, &transport, packet, sizeof(packet)) !=
+            TRIKKE_TRANSPORT_COMPLETE ||
+        sender.pending || mock.begin_calls != 3) {
+        return fail(5, "synchronous completion contract");
+    }
+
+    mock.begin_status = TRIKKE_TRANSPORT_PENDING;
+    mock.poll_status = TRIKKE_TRANSPORT_RETRY;
+    if (trikke_transport_sender_step(
+            &sender, &transport, packet, sizeof(packet)) !=
+            TRIKKE_TRANSPORT_PENDING ||
+        trikke_transport_sender_step(
+            &sender, &transport, packet, sizeof(packet)) !=
+            TRIKKE_TRANSPORT_RETRY ||
+        sender.pending) {
+        return fail(6, "backend-confirmed safe retry must return to idle");
+    }
+
+    if (trikke_transport_sender_step(
+            NULL, &transport, packet, sizeof(packet)) !=
+            TRIKKE_TRANSPORT_FATAL ||
+        trikke_transport_sender_step(
+            &sender, NULL, packet, sizeof(packet)) != TRIKKE_TRANSPORT_FATAL ||
+        trikke_transport_sender_step(
+            &sender, &transport, NULL, sizeof(packet)) !=
+            TRIKKE_TRANSPORT_FATAL ||
+        trikke_transport_sender_step(
+            &sender, &transport, packet, 0) != TRIKKE_TRANSPORT_FATAL) {
+        return fail(7, "invalid arguments must fail closed");
+    }
+
+    mock.begin_status = (trikke_transport_status_t)99;
+    if (trikke_transport_sender_step(
+            &sender, &transport, packet, sizeof(packet)) !=
+            TRIKKE_TRANSPORT_FATAL ||
+        sender.pending) {
+        return fail(8, "unknown backend status must fail closed");
+    }
+
+    return 0;
+}