bootp/dhcp6: DHCPv4/v6 ZTP and SZTP option support

[tcpdump] / print-bootp.c

diff --git a/print-bootp.c b/print-bootp.c
index d5418d976b41dc1b197c374761fb4a43db9032f9..227ed41050704bd1f12fa14dc54e1a4257b7fcc0 100644 (file)
--- a/print-bootp.c
+++ b/print-bootp.c
@@ -194,6 +194,8 @@ struct bootp {
 /* RFC 3442 */
 #define TAG_CLASSLESS_STATIC_RT        ((uint8_t) 121)
 #define TAG_CLASSLESS_STA_RT_MS        ((uint8_t) 249)
+/* RFC8572 */
+#define TAG_SZTP_REDIRECT      ((uint8_t) 143)
 /* RFC 5859 - TFTP Server Address Option for DHCPv4 */
 #define        TAG_TFTP_SERVER_ADDRESS ((uint8_t) 150)
 /* https://www.iana.org/assignments/bootp-dhcp-parameters/bootp-dhcp-parameters.xhtml */
@@ -506,6 +508,8 @@ static const struct tok tag2str[] = {
 /* RFC 3442 */
        { TAG_CLASSLESS_STATIC_RT, "$Classless-Static-Route" },
        { TAG_CLASSLESS_STA_RT_MS, "$Classless-Static-Route-Microsoft" },
+/* RFC 8572 */
+       { TAG_SZTP_REDIRECT,    "$SZTP-Redirect" },
 /* RFC 5859 - TFTP Server Address Option for DHCPv4 */
        { TAG_TFTP_SERVER_ADDRESS, "iTFTP-Server-Address" },
 /* https://www.iana.org/assignments/bootp-dhcp-parameters/bootp-dhcp-parameters.xhtml#options */
@@ -993,6 +997,39 @@ rfc1048_print(netdissect_options *ndo,
                                break;
                            }
 
+
+                       case TAG_SZTP_REDIRECT:
+                               /* as per https://datatracker.ietf.org/doc/html/rfc8572#section-8.3
+                                +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...-+-+-+-+-+-+-+
+                                |        uri-length             |          URI                  |
+                                +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...-+-+-+-+-+-+-+
+
+                                * uri-length: 2 octets long; specifies the length of the URI data.
+                                * URI: URI of the SZTP bootstrap server.
+                                */
+                               while (len >= 2) {
+                                       suboptlen = GET_BE_U_2(bp);
+                                       bp += 2;
+                                       len -= 2;
+                                       ND_PRINT("\n\t      ");
+                                       ND_PRINT("length %u: ", suboptlen);
+                                       if (len < suboptlen) {
+                                               ND_PRINT("length goes past end of option");
+                                               bp += len;
+                                               len = 0;
+                                               break;
+                                       }
+                                       ND_PRINT("\"");
+                                       nd_printjn(ndo, bp, suboptlen);
+                                       ND_PRINT("\"");
+                                       len -= suboptlen;
+                                       bp += suboptlen;
+                               }
+                               if (len != 0) {
+                                       ND_PRINT("[ERROR: length < 2 bytes]");
+                               }
+                               break;
+
                        default:
                                ND_PRINT("[unknown special tag %u, size %u]",
                                          tag, len);