Rename EXTRACT_ macros

[tcpdump] / print-tftp.c

diff --git a/print-tftp.c b/print-tftp.c
index acb8ca9d6947f25d5de0cbfec35eb1eadd0789f3..314dfb41eff0d7d86ef769dee41bda3c7f9ea832 100644 (file)
--- a/print-tftp.c
+++ b/print-tftp.c
@@ -17,19 +17,19 @@
  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
- *
- * Format and print trivial file transfer protocol packets.
  */
 
+/* \summary: Trivial File Transfer Protocol (TFTP) printer */
+
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
-#include <tcpdump-stdinc.h>
+#include <netdissect-stdinc.h>
 
 #include <string.h>
 
-#include "interface.h"
+#include "netdissect.h"
 #include "extract.h"
 
 /*
@@ -46,21 +46,6 @@
 #define        TFTP_ERROR      05                      /* error code */
 #define OACK   06                      /* option acknowledgement */
 
-struct tftphdr {
-       unsigned short  th_opcode;              /* packet type */
-       union {
-               unsigned short  tu_block;       /* block # */
-               unsigned short  tu_code;        /* error code */
-               char    tu_stuff[1];    /* request packet stuff */
-       } th_u;
-       char    th_data[1];             /* data or error string */
-};
-
-#define        th_block        th_u.tu_block
-#define        th_code         th_u.tu_code
-#define        th_stuff        th_u.tu_stuff
-#define        th_msg          th_data
-
 /*
  * Error codes.
  */
@@ -106,69 +91,103 @@ void
 tftp_print(netdissect_options *ndo,
            register const u_char *bp, u_int length)
 {
-       register const struct tftphdr *tp;
        register const char *cp;
-       register const u_char *p;
-       register int opcode, i;
-
-       tp = (const struct tftphdr *)bp;
+       register int opcode;
+       u_int ui;
 
        /* Print length */
        ND_PRINT((ndo, " %d", length));
 
        /* Print tftp request type */
-       ND_TCHECK(tp->th_opcode);
-       opcode = EXTRACT_16BITS(&tp->th_opcode);
+       if (length < 2)
+               goto trunc;
+       ND_TCHECK_2(bp);
+       opcode = EXTRACT_BE_U_2(bp);
        cp = tok2str(op2str, "tftp-#%d", opcode);
        ND_PRINT((ndo, " %s", cp));
        /* Bail if bogus opcode */
        if (*cp == 't')
                return;
+       bp += 2;
+       length -= 2;
 
        switch (opcode) {
 
        case RRQ:
        case WRQ:
-       case OACK:
-               p = (u_char *)tp->th_stuff;
+               if (length == 0)
+                       goto trunc;
+               ND_PRINT((ndo, " "));
+               /* Print filename */
+               ND_PRINT((ndo, "\""));
+               ui = fn_printztn(ndo, bp, length, ndo->ndo_snapend);
+               ND_PRINT((ndo, "\""));
+               if (ui == 0)
+                       goto trunc;
+               bp += ui;
+               length -= ui;
+
+               /* Print the mode - RRQ and WRQ only */
+               if (length == 0)
+                       goto trunc;     /* no mode */
                ND_PRINT((ndo, " "));
-               /* Print filename or first option */
-               if (opcode != OACK)
-                       ND_PRINT((ndo, "\""));
-               i = fn_print(ndo, p, ndo->ndo_snapend);
-               if (opcode != OACK)
-                       ND_PRINT((ndo, "\""));
-
-               /* Print the mode (RRQ and WRQ only) and any options */
-               while ((p = (const u_char *)strchr((const char *)p, '\0')) != NULL) {
-                       if (length <= (u_int)(p - (const u_char *)&tp->th_block))
-                               break;
-                       p++;
-                       if (*p != '\0') {
+               ui = fn_printztn(ndo, bp, length, ndo->ndo_snapend);
+               if (ui == 0)
+                       goto trunc;
+               bp += ui;
+               length -= ui;
+
+               /* Print options, if any */
+               while (length != 0) {
+                       ND_TCHECK(*bp);
+                       if (*bp != '\0')
                                ND_PRINT((ndo, " "));
-                               fn_print(ndo, p, ndo->ndo_snapend);
-                       }
+                       ui = fn_printztn(ndo, bp, length, ndo->ndo_snapend);
+                       if (ui == 0)
+                               goto trunc;
+                       bp += ui;
+                       length -= ui;
                }
+               break;
 
-               if (i)
-                       goto trunc;
+       case OACK:
+               /* Print options */
+               while (length != 0) {
+                       ND_TCHECK(*bp);
+                       if (*bp != '\0')
+                               ND_PRINT((ndo, " "));
+                       ui = fn_printztn(ndo, bp, length, ndo->ndo_snapend);
+                       if (ui == 0)
+                               goto trunc;
+                       bp += ui;
+                       length -= ui;
+               }
                break;
 
        case ACK:
        case DATA:
-               ND_TCHECK(tp->th_block);
-               ND_PRINT((ndo, " block %d", EXTRACT_16BITS(&tp->th_block)));
+               if (length < 2)
+                       goto trunc;     /* no block number */
+               ND_TCHECK_2(bp);
+               ND_PRINT((ndo, " block %d", EXTRACT_BE_U_2(bp)));
                break;
 
        case TFTP_ERROR:
                /* Print error code string */
-               ND_TCHECK(tp->th_code);
-               ND_PRINT((ndo, " %s \"", tok2str(err2str, "tftp-err-#%d \"",
-                                      EXTRACT_16BITS(&tp->th_code))));
+               if (length < 2)
+                       goto trunc;     /* no error code */
+               ND_TCHECK_2(bp);
+               ND_PRINT((ndo, " %s", tok2str(err2str, "tftp-err-#%d \"",
+                                      EXTRACT_BE_U_2(bp))));
+               bp += 2;
+               length -= 2;
                /* Print error message string */
-               i = fn_print(ndo, (const u_char *)tp->th_data, ndo->ndo_snapend);
+               if (length == 0)
+                       goto trunc;     /* no error message */
+               ND_PRINT((ndo, " \""));
+               ui = fn_printztn(ndo, bp, length, ndo->ndo_snapend);
                ND_PRINT((ndo, "\""));
-               if (i)
+               if (ui == 0)
                        goto trunc;
                break;