diff options
Diffstat (limited to 'print-syslog.c')
| -rw-r--r-- | print-syslog.c | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/print-syslog.c b/print-syslog.c new file mode 100644 index 0000000..b0e1c91 --- /dev/null +++ b/print-syslog.c @@ -0,0 +1,150 @@ +/* + * Copyright (c) 1998-2004 Hannes Gredler <hannes@gredler.at> + * The TCPDUMP project + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that: (1) source code + * distributions retain the above copyright notice and this paragraph + * in its entirety, and (2) distributions including binary code include + * the above copyright notice and this paragraph in its entirety in + * the documentation or other materials provided with the distribution. + * 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. + */ + +/* \summary: Syslog protocol printer */ +/* specification: RFC 3164 (not RFC 5424) */ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include "netdissect-stdinc.h" + +#include "netdissect.h" +#include "extract.h" + + +/* + * tokenlists and #defines taken from Ethereal - Network traffic analyzer + * by Gerald Combs <gerald@ethereal.com> + */ + +#define SYSLOG_SEVERITY_MASK 0x0007 /* 0000 0000 0000 0111 */ +#define SYSLOG_FACILITY_MASK 0x03f8 /* 0000 0011 1111 1000 */ +#define SYSLOG_MAX_DIGITS 3 /* The maximum number of priority digits to read in. */ + +static const struct tok syslog_severity_values[] = { + { 0, "emergency" }, + { 1, "alert" }, + { 2, "critical" }, + { 3, "error" }, + { 4, "warning" }, + { 5, "notice" }, + { 6, "info" }, + { 7, "debug" }, + { 0, NULL }, +}; + +static const struct tok syslog_facility_values[] = { + { 0, "kernel" }, + { 1, "user" }, + { 2, "mail" }, + { 3, "daemon" }, + { 4, "auth" }, + { 5, "syslog" }, + { 6, "lpr" }, + { 7, "news" }, + { 8, "uucp" }, + { 9, "cron" }, + { 10, "authpriv" }, + { 11, "ftp" }, + { 12, "ntp" }, + { 13, "security" }, + { 14, "console" }, + { 15, "cron" }, + { 16, "local0" }, + { 17, "local1" }, + { 18, "local2" }, + { 19, "local3" }, + { 20, "local4" }, + { 21, "local5" }, + { 22, "local6" }, + { 23, "local7" }, + { 0, NULL }, +}; + +void +syslog_print(netdissect_options *ndo, + const u_char *pptr, u_int len) +{ + uint16_t msg_off = 0; + uint16_t pri = 0; + uint16_t facility,severity; + + ndo->ndo_protocol = "syslog"; + /* extract decimal figures that are + * encapsulated within < > tags + * based on this decimal figure extract the + * severity and facility values + */ + + if (GET_U_1(pptr) != '<') + goto invalid; + msg_off++; + + while (msg_off <= SYSLOG_MAX_DIGITS && + GET_U_1(pptr + msg_off) >= '0' && + GET_U_1(pptr + msg_off) <= '9') { + pri = pri * 10 + (GET_U_1(pptr + msg_off) - '0'); + msg_off++; + } + + if (GET_U_1(pptr + msg_off) != '>') + goto invalid; + msg_off++; + + facility = (pri & SYSLOG_FACILITY_MASK) >> 3; + severity = pri & SYSLOG_SEVERITY_MASK; + + if (ndo->ndo_vflag < 1 ) + { + ND_PRINT("SYSLOG %s.%s, length: %u", + tok2str(syslog_facility_values, "unknown (%u)", facility), + tok2str(syslog_severity_values, "unknown (%u)", severity), + len); + return; + } + + ND_PRINT("SYSLOG, length: %u\n\tFacility %s (%u), Severity %s (%u)\n\tMsg: ", + len, + tok2str(syslog_facility_values, "unknown (%u)", facility), + facility, + tok2str(syslog_severity_values, "unknown (%u)", severity), + severity); + + /* print the syslog text in verbose mode */ + /* + * RFC 3164 Section 4.1.3: "There is no ending delimiter to this part. + * The MSG part of the syslog packet MUST contain visible (printing) + * characters." + * + * RFC 5424 Section 8.2: "This document does not impose any mandatory + * restrictions on the MSG or PARAM-VALUE content. As such, they MAY + * contain control characters, including the NUL character." + * + * Hence, to aid in protocol debugging, print the full MSG without + * beautification to make it clear what was transmitted on the wire. + */ + if (len > msg_off) + (void)nd_printn(ndo, pptr + msg_off, len - msg_off, NULL); + + if (ndo->ndo_vflag > 1) + print_unknown_data(ndo, pptr, "\n\t", len); + return; + +invalid: + nd_print_invalid(ndo); +} |