init

2026-06-26 00:30:13 +02:00
commit b27cd76ca8
122 changed files with 37290 additions and 0 deletions
@@ -0,0 +1,107 @@
+#include "ch32v20x_rtc.h"
+#include "meshcore/meshframing.h"
+#include "meshcore/packetstructs.h"
+#include "group.h"
+#include "lib/config.h"
+#include "util/hexdump.h"
+#include "util/log.h"
+#include "string.h"
+
+#define TAG "GroupMessage"
+
+void sendGroupMessage (const GroupTextMessage *msg) {
+    // Prepare values locally instead of modifying msg
+    Channel *channel = &(persistent.channels[msg->keyIndex]);
+    uint8_t flags = 0;
+    int32_t timestamp = RTC_GetCounter();
+
+    FrameStruct frame;
+    frame.header = ROUTE_TYPE_FLOOD | PAYLOAD_TYPE_GRP_TXT | PAYLOAD_VERSION_0;
+    frame.path.pathLen = 0;
+    size_t offset = 0;
+    frame.payload[offset++] = channel->hash;
+
+    // Build encryption buffer directly on stack (no extra large buffer)
+    uint8_t buf[180];  // enough for timestamp + flags + text
+    size_t buf_offset = 0;
+
+    memcpy (buf + buf_offset, &timestamp, sizeof (timestamp));
+    buf_offset += sizeof (timestamp);
+
+    buf[buf_offset++] = flags;
+
+    size_t textLen = strlen ((const char *)msg->text);
+    if (buf_offset + textLen > sizeof (buf)) {
+        textLen = sizeof (buf) - buf_offset;
+    }
+    memcpy (buf + buf_offset, msg->text, textLen);
+    buf_offset += textLen;
+
+    hexdump ("TxDumpDec", buf, buf_offset);
+
+    // Encrypt and MAC directly into frame payload after channelHash
+    size_t olen = 0;
+
+    encrypt_then_mac (channel->key, 16, buf, buf_offset, &frame.payload[offset], &olen);
+
+    frame.payloadLen = olen + 1;  // +1 for channelHash
+
+    channel->timestamp = timestamp;
+
+    LoRaTransmit (&frame);
+}
+
+void makeSendGroupMessage (char *txt, uint8_t keyIndex) {
+    GroupTextMessage msg;
+    strcpy ((char *)msg.text, persistent.nodeName);
+    strcat ((char *)msg.text, ": ");
+    strcat ((char *)msg.text, txt);
+    msg.keyIndex = keyIndex;
+    sendGroupMessage (&msg);
+    return;
+}
+
+void decodeGroupMessage (const FrameStruct *frame) {
+    GroupTextMessage msg;
+    memset (&msg, 0, sizeof (msg));
+    if ((frame->header & PAYLOAD_TYPE_MASK) != PAYLOAD_TYPE_GRP_TXT) {
+        MESH_LOGW (TAG, "Not a group text");
+        return;
+    }
+    unsigned char index = 0;
+    msg.channelHash = frame->payload[index++];
+    unsigned char tmp[184];
+
+
+    Channel *channel = NULL;
+
+    uint8_t i = 0;
+    do {
+        channel = getChannel (msg.channelHash, i);
+        if (channel == NULL) {
+            MESH_LOGW (TAG, "Channel hash %d not found", msg.channelHash);
+            return;
+        }
+        if (mac_then_decrypt (channel->key, 16, frame->payload + index, frame->payloadLen - index, tmp) != 0) {
+            MESH_LOGW (TAG, "HMAC failed on grouphash key %d", msg.channelHash);
+            i++;
+            continue;
+        } else {
+            unsigned char plaintextLen = frame->payloadLen - index;
+            index = 0;
+
+            memcpy (&msg.timestamp, tmp + index, 4);
+            index += 4;
+            msg.flags = tmp[index++];
+
+            memcpy (msg.text, tmp + index, plaintextLen - index);
+
+            channel->timestamp = RTC_GetCounter();
+
+            iprintf ("Message from channel %s: %s\n", channel->name, msg.text);
+            break;
+        }
+
+
+    } while (channel != NULL);
+}