From af00174af3ef478d7d8d96d15647ad1bbb0bc919 Mon Sep 17 00:00:00 2001 From: Fernando Fernandez Mancera Date: Wed, 22 Aug 2018 17:03:46 +0200 Subject: src: osf: import nfnl_osf.c to load osf fingerprints Import iptables/utils/nfnl_osf.c into nftables tree with some changes in order to load OS fingerprints automatically from pf.os file. Signed-off-by: Fernando Fernandez Mancera Signed-off-by: Pablo Neira Ayuso --- include/linux/netfilter/Makefile.am | 1 + include/linux/netfilter/nfnetlink_osf.h | 119 ++++++++++++++++++++++++++++++++ 2 files changed, 120 insertions(+) create mode 100644 include/linux/netfilter/nfnetlink_osf.h (limited to 'include/linux/netfilter') diff --git a/include/linux/netfilter/Makefile.am b/include/linux/netfilter/Makefile.am index f6a8aa22..2c1de184 100644 --- a/include/linux/netfilter/Makefile.am +++ b/include/linux/netfilter/Makefile.am @@ -3,4 +3,5 @@ noinst_HEADERS = nf_conntrack_common.h \ nf_log.h \ nf_nat.h \ nf_tables.h \ + nfnetlink_osf.h \ nfnetlink.h diff --git a/include/linux/netfilter/nfnetlink_osf.h b/include/linux/netfilter/nfnetlink_osf.h new file mode 100644 index 00000000..15a39d29 --- /dev/null +++ b/include/linux/netfilter/nfnetlink_osf.h @@ -0,0 +1,119 @@ +#ifndef _NF_OSF_H +#define _NF_OSF_H + +#include + +#define MAXGENRELEN 32 + +#define NF_OSF_GENRE (1 << 0) +#define NF_OSF_TTL (1 << 1) +#define NF_OSF_LOG (1 << 2) +#define NF_OSF_INVERT (1 << 3) + +#define NF_OSF_LOGLEVEL_ALL 0 /* log all matched fingerprints */ +#define NF_OSF_LOGLEVEL_FIRST 1 /* log only the first matced fingerprint */ +#define NF_OSF_LOGLEVEL_ALL_KNOWN 2 /* do not log unknown packets */ + +#define NF_OSF_TTL_TRUE 0 /* True ip and fingerprint TTL comparison */ + +/* Check if ip TTL is less than fingerprint one */ +#define NF_OSF_TTL_LESS 1 + +/* Do not compare ip and fingerprint TTL at all */ +#define NF_OSF_TTL_NOCHECK 2 + +#define NF_OSF_FLAGMASK (NF_OSF_GENRE | NF_OSF_TTL | \ + NF_OSF_LOG | NF_OSF_INVERT) +/* Wildcard MSS (kind of). + * It is used to implement a state machine for the different wildcard values + * of the MSS and window sizes. + */ +struct nf_osf_wc { + __u32 wc; + __u32 val; +}; + +/* This struct represents IANA options + * http://www.iana.org/assignments/tcp-parameters + */ +struct nf_osf_opt { + __u16 kind, length; + struct nf_osf_wc wc; +}; + +struct nf_osf_info { + char genre[MAXGENRELEN]; + __u32 len; + __u32 flags; + __u32 loglevel; + __u32 ttl; +}; + +struct nf_osf_user_finger { + struct nf_osf_wc wss; + + __u8 ttl, df; + __u16 ss, mss; + __u16 opt_num; + + char genre[MAXGENRELEN]; + char version[MAXGENRELEN]; + char subtype[MAXGENRELEN]; + + /* MAX_IPOPTLEN is maximum if all options are NOPs or EOLs */ + struct nf_osf_opt opt[MAX_IPOPTLEN]; +}; + +struct nf_osf_nlmsg { + struct nf_osf_user_finger f; + struct iphdr ip; + struct tcphdr tcp; +}; + +/* Defines for IANA option kinds */ +enum iana_options { + OSFOPT_EOL = 0, /* End of options */ + OSFOPT_NOP, /* NOP */ + OSFOPT_MSS, /* Maximum segment size */ + OSFOPT_WSO, /* Window scale option */ + OSFOPT_SACKP, /* SACK permitted */ + OSFOPT_SACK, /* SACK */ + OSFOPT_ECHO, + OSFOPT_ECHOREPLY, + OSFOPT_TS, /* Timestamp option */ + OSFOPT_POCP, /* Partial Order Connection Permitted */ + OSFOPT_POSP, /* Partial Order Service Profile */ + + /* Others are not used in the current OSF */ + OSFOPT_EMPTY = 255, +}; + +/* + * Initial window size option state machine: multiple of mss, mtu or + * plain numeric value. Can also be made as plain numeric value which + * is not a multiple of specified value. + */ +enum nf_osf_window_size_options { + OSF_WSS_PLAIN = 0, + OSF_WSS_MSS, + OSF_WSS_MTU, + OSF_WSS_MODULO, + OSF_WSS_MAX, +}; + +enum nf_osf_attr_type { + OSF_ATTR_UNSPEC, + OSF_ATTR_FINGER, + OSF_ATTR_MAX, +}; + +/* + * Add/remove fingerprint from the kernel. + */ +enum nf_osf_msg_types { + OSF_MSG_ADD, + OSF_MSG_REMOVE, + OSF_MSG_MAX, +}; + +#endif /* _NF_OSF_H */ -- cgit v1.2.3