typo fix and check if tx packets larger than allowed

Author: edvardxyz

include/cblk/csp_if_cblk.h

@@ -33,7 +33,7 @@ typedef struct __attribute__((packed))
 #define CCSDS_FRAME_LEN 223
 #define CBLK_DATA_LEN (CCSDS_FRAME_LEN-sizeof(cblk_hdr_t))
 #define CRYPTO_PREAMP 16 /* crypto_secretbox_BOXZEROBYTES */
-#define CRYPTO_POSTAMP (16+9) /* 16 zero fill + NOUNCE_SIZE */
+#define CRYPTO_POSTAMP (16+9) /* 16 zero fill + NONCE_SIZE */
 #define CRYPTO_MAC_SIZE 16
 /* ccsds frame index is 4 bits */
 #define CBLK_MAX_FRAMES_PER_PACKET 15

src/csp_if_cblk.c

@@ -1,6 +1,5 @@
 #include "cblk/csp_if_cblk.h"
 
-#include <math.h>
 #include <stdio.h>
 #include <endian.h>
 #include <csp/crypto/csp_hmac.h>
@@ -84,6 +83,14 @@ int csp_if_cblk_tx(csp_iface_t * iface, uint16_t via, csp_packet_t *packet, int
     uint16_t bytes_remain = packet->frame_length;
     uint8_t num_frames = num_ccsds_from_csp(packet->frame_length);
 
+    if(num_frames == 0) {
+        csp_buffer_free(packet);
+        if (_cblk_tx_debug >= 1) {
+            printf("Packet too large to send: %u bytes\n", packet->frame_length);
+        }
+        return CSP_ERR_INVAL;
+    }
+
     ifdata->cblk_tx_lock(iface);
 
     for (int8_t frame_cnt = 0; frame_cnt < num_frames; frame_cnt++) {