/* Copyright (C) 2000,2001 Salvatore Sanfilippo * See the LICENSE file for more information. */ /* $Id: ars.h,v 1.3 2003/07/28 09:00:55 njombart Exp $ */ #ifndef _ARS_H #define _ARS_H /* define before including sys/socket.h */ #if defined(__APPLE__) #define _BSD_SOCKLEN_T_ int #endif #include #include #include "systype.h" #include "in.h" #include "bytesex.h" #ifndef TRUE #define TRUE 1 #define FALSE 0 #endif #ifndef MIN #define MIN(x,y) ((x)<(y)?(x):(y)) #endif #ifndef MAX #define MAX(x,y) ((x)>(y)?(x):(y)) #endif #ifdef DEBUG #define __D(x) x #else #define __D(x) do { } while (0); #endif #ifndef __u8 #define __u8 u_int8_t #define __u16 u_int16_t #define __u32 u_int32_t #endif /* error codes */ #define ARS_OK 0 #define ARS_ERROR 1 #define ARS_NOSPACE 2 #define ARS_NOMEM 3 #define ARS_INVALID 4 /* Headers size */ #define ARS_ICMPHDR_SIZE sizeof(struct ars_icmphdr) #define ARS_UDPHDR_SIZE sizeof(struct ars_udphdr) #define ARS_TCPHDR_SIZE sizeof(struct ars_tcphdr) #define ARS_IPHDR_SIZE sizeof(struct ars_iphdr) #define ARS_PSEUDOHDR_SIZE sizeof(struct pseudohdr) /* IP defines */ #define ARS_MAX_IP_SIZE 65535 #define ARS_IP_MF ((unsigned short)0x2000) /* more fragments */ #define ARS_IP_DF ((unsigned short)0x4000) /* dont fragment */ #define ARS_IP_RF ((unsigned short)0x8000) /* reserved fragment flag */ #define ARS_IPOPT_COPY 0x80 #define ARS_IPOPT_CLASS_MASK 0x60 #define ARS_IPOPT_NUMBER_MASK 0x1f #define ARS_IPOPT_COPIED(o) ((o)&ARS_IPOPT_COPY) #define ARS_IPOPT_CLASS(o) ((o)&ARS_IPOPT_CLASS_MASK) #define ARS_IPOPT_NUMBER(o) ((o)&ARS_IPOPT_NUMBER_MASK) #define ARS_IPOPT_CONTROL 0x00 #define ARS_IPOPT_RESERVED1 0x20 #define ARS_IPOPT_MEASUREMENT 0x40 #define ARS_IPOPT_RESERVED2 0x60 #define ARS_IPOPT_END (0 |ARS_IPOPT_CONTROL) #define ARS_IPOPT_NOOP (1 |ARS_IPOPT_CONTROL) #define ARS_IPOPT_SEC (2 |ARS_IPOPT_CONTROL|ARS_IPOPT_COPY) #define ARS_IPOPT_LSRR (3 |ARS_IPOPT_CONTROL|ARS_IPOPT_COPY) #define ARS_IPOPT_TIMESTAMP (4 |ARS_IPOPT_MEASUREMENT) #define ARS_IPOPT_RR (7 |ARS_IPOPT_CONTROL) #define ARS_IPOPT_SID (8 |ARS_IPOPT_CONTROL|ARS_IPOPT_COPY) #define ARS_IPOPT_SSRR (9 |ARS_IPOPT_CONTROL|ARS_IPOPT_COPY) #define ARS_IPOPT_RA (20|ARS_IPOPT_CONTROL|ARS_IPOPT_COPY) #define ARS_IPOPT_OPTVAL 0 #define ARS_IPOPT_OLEN 1 #define ARS_IPOPT_OFFSET 2 #define ARS_IPOPT_MINOFF 4 #define ARS_MAX_IPOPTLEN 40 #define ARS_IPOPT_NOP ARS_IPOPT_NOOP #define ARS_IPOPT_EOL ARS_IPOPT_END #define ARS_IPOPT_TS ARS_IPOPT_TIMESTAMP #define ARS_IPOPT_TS_TSONLY 0 /* timestamps only */ #define ARS_IPOPT_TS_TSANDADDR 1 /* timestamps and addresses */ #define ARS_IPOPT_TS_PRESPEC 3 /* specified modules only */ /* IPV4 and IPV6 string rappresentation len */ #define ARS_INET_ADDRSTRLEN 16 #define ARS_INET6_ADDRSTRLEN 46 /* TCP */ #define ARS_TCPOPT_EOL 0 #define ARS_TCPOPT_NOP 1 #define ARS_TCPOPT_MAXSEG 2 #define ARS_TCPOPT_WINDOW 3 #define ARS_TCPOPT_SACK_PERM 4 #define ARS_TCPOPT_SACK 5 #define ARS_TCPOPT_ECHOREQUEST 6 #define ARS_TCPOPT_ECHOREPLY 7 #define ARS_TCPOPT_TIMESTAMP 8 #define ARS_TCP_TH_FIN 0x01 #define ARS_TCP_TH_SYN 0x02 #define ARS_TCP_TH_RST 0x04 #define ARS_TCP_TH_PUSH 0x08 #define ARS_TCP_TH_ACK 0x10 #define ARS_TCP_TH_URG 0x20 #define ARS_TCP_TH_X 0x40 /* X tcp flag */ #define ARS_TCP_TH_Y 0x80 /* Y tcp flag */ /* ICMP TYPE */ #define ARS_ICMP_ECHOREPLY 0 /* Echo Reply */ #define ARS_ICMP_DEST_UNREACH 3 /* Destination Unreachable */ #define ARS_ICMP_SOURCE_QUENCH 4 /* Source Quench */ #define ARS_ICMP_REDIRECT 5 /* Redirect (change route) */ #define ARS_ICMP_ECHO 8 /* Echo Request */ #define ARS_ICMP_TIME_EXCEEDED 11 /* Time Exceeded */ #define ARS_ICMP_PARAMETERPROB 12 /* Parameter Problem */ #define ARS_ICMP_TIMESTAMP 13 /* Timestamp Request */ #define ARS_ICMP_TIMESTAMPREPLY 14 /* Timestamp Reply */ #define ARS_ICMP_INFO_REQUEST 15 /* Information Request */ #define ARS_ICMP_INFO_REPLY 16 /* Information Reply */ #define ARS_ICMP_ADDRESS 17 /* Address Mask Request */ #define ARS_ICMP_ADDRESSREPLY 18 /* Address Mask Reply */ /* Codes for UNREACHABLE */ #define ARS_ICMP_UNR_NET 0 /* Network Unreachable */ #define ARS_ICMP_UNR_HOST 1 /* Host Unreachable */ #define ARS_ICMP_UNR_PROT 2 /* Protocol Unreachable */ #define ARS_ICMP_UNR_PORT 3 /* Port Unreachable */ #define ARS_ICMP_UNR_FRAG_NEEDED 4 /* Fragmentation Needed,DF set*/ #define ARS_ICMP_UNR_SR_FAILED 5 /* Source Route failed */ #define ARS_ICMP_UNR_UNK_NET 6 #define ARS_ICMP_UNR_UNK_HOST 7 #define ARS_ICMP_UNR_ISOLATED_HOST 8 #define ARS_ICMP_UNR_NET_ANO 9 #define ARS_ICMP_UNR_HOST_ANO 10 #define ARS_ICMP_UNR_NET_UNR_TOS 11 #define ARS_ICMP_UNR_HOST_UNR_TOS 12 #define ARS_ICMP_UNR_PKT_FILTERED 13 /* Packet filtered */ #define ARS_ICMP_UNR_PREC_VIOLATION 14 /* Precedence violation */ #define ARS_ICMP_UNR_PREC_CUTOFF 15 /* Precedence cut off */ #define ARS_NR_ICMP_UNREACH 15 /* Instead of hardcoded immediate value */ /* Codes for REDIRECT */ #define ARS_ICMP_REDIR_NET 0 /* Redirect Net */ #define ARS_ICMP_REDIR_HOST 1 /* Redirect Host */ #define ARS_ICMP_REDIR_NETTOS 2 /* Redirect Net for TOS */ #define ARS_ICMP_REDIR_HOSTTOS 3 /* Redirect Host for TOS */ /* Codes for TIME_EXCEEDED */ #define ARS_ICMP_EXC_TTL 0 /* TTL count exceeded */ #define ARS_ICMP_EXC_FRAGTIME 1 /* TTL exceeded reassembling */ /* The IP header structure */ struct ars_iphdr { #if defined(BYTE_ORDER_LITTLE_ENDIAN) __u8 ihl:4, version:4; #elif defined (BYTE_ORDER_BIG_ENDIAN) __u8 version:4, ihl:4; #else #error "Please, edit Makefile and add -DBYTE_ORDER_(BIG|LITTLE)_ENDIAN" #endif __u8 tos; __u16 tot_len; __u16 id; __u16 frag_off; __u8 ttl; __u8 protocol; __u16 check; __u32 saddr; __u32 daddr; }; /* The IP options structure */ struct ars_ipopt { u_int8_t kind; u_int8_t len; union { struct { u_int16_t s; u_int16_t c; u_int16_t h; u_int8_t tcc[3]; } sec; /* security */ struct { u_int8_t ptr; u_int8_t data[37]; } src; /* loose and strinct source routing */ struct { u_int8_t ptr; u_int8_t data[37]; } rr; /* record route */ struct { u_int16_t id; } sid; /* stream id */ struct { u_int8_t ptr; u_int8_t flags; u_int8_t data[36]; } tstamp; /* timestamp */ } un; }; /* The UDP header structure */ struct ars_udphdr { __u16 uh_sport; /* source port */ __u16 uh_dport; /* destination port */ __u16 uh_ulen; /* udp length */ __u16 uh_sum; /* udp checksum */ }; /* The TCP header structure */ struct ars_tcphdr { __u16 th_sport; /* source port */ __u16 th_dport; /* destination port */ __u32 th_seq; /* sequence number */ __u32 th_ack; /* acknowledgement number */ #if defined (BYTE_ORDER_LITTLE_ENDIAN) __u8 th_x2:4, /* (unused) */ th_off:4; /* data offset */ #elif defined (BYTE_ORDER_BIG_ENDIAN) __u8 th_off:4, /* data offset */ th_x2:4; /* (unused) */ #else #error "Please, edit Makefile and add -DBYTE_ORDER_(BIG|LITTLE)_ENDIAN" #endif __u8 th_flags; __u16 th_win; /* window */ __u16 th_sum; /* checksum */ __u16 th_urp; /* urgent pointer */ }; /* The TCP options structure */ struct ars_tcpopt { u_int8_t kind; u_int8_t len; union { struct { u_int16_t size; } mss; struct { u_int8_t shift; } win; struct { u_int16_t origin; u_int16_t size; } sack[10]; /* 10 SACK blocks in 44 bytes of space */ struct { u_int8_t info[4]; } echo; struct { u_int8_t tsval[4]; u_int8_t tsecr[4]; } timestamp; } un; }; /* The ICMP header structure */ struct ars_icmphdr { __u8 type; __u8 code; __u16 checksum; union { struct { __u16 id; __u16 sequence; } echo; /* called echo since it's the most used */ __u32 gateway; } un; }; /* TCP/UDP pseudo header used to compute the checksum */ struct ars_pseudohdr { __u32 saddr; __u32 daddr; __u8 zero; __u8 protocol; __u16 lenght; }; struct ars_packet; /* forward declaration */ /* ARS layer */ struct ars_layer { int l_type; int l_size; int l_flags; void *l_data; struct ars_packet *l_packet; }; #define ARS_MAX_LAYER 16 /* Types */ #define ARS_TYPE_SIZE 32 #define ARS_TYPE_NULL 0 #define ARS_TYPE_IP 1 #define ARS_TYPE_IPOPT 2 #define ARS_TYPE_ICMP 3 #define ARS_TYPE_UDP 4 #define ARS_TYPE_TCP 5 #define ARS_TYPE_TCPOPT 6 #define ARS_TYPE_DATA 31 /* ARS packet context */ struct ars_packet { char *p_error; int p_layer_nr; struct ars_layer p_layer[ARS_MAX_LAYER]; void *p_default[ARS_TYPE_SIZE]; int aux; /* Auxiliar variable for data exchange between functions */ }; /* Facility to check for flags */ #define ARS_TAKE(f,x) (f & x) #define ARS_DONTTAKE(f, x) (!(f & x)) #define ARS_TAKE_NONE 0 /* IP layer flags */ #define ARS_TAKE_IP_VERSION (1 << 0) #define ARS_TAKE_IP_HDRLEN (1 << 1) #define ARS_TAKE_IP_TOTLEN (1 << 2) #define ARS_TAKE_IP_PROTOCOL (1 << 3) #define ARS_TAKE_IP_CKSUM (1 << 4) /* ICMP layer flags */ #define ARS_TAKE_ICMP_CKSUM (1 << 0) /* UDP layer flags */ #define ARS_TAKE_UDP_CKSUM (1 << 0) #define ARS_TAKE_UDP_LEN (1 << 1) /* TCP layer flags */ #define ARS_TAKE_TCP_HDRLEN (1 << 0) #define ARS_TAKE_TCP_CKSUM (1 << 1) /* Some function that acts on layer switch to the last layer with this */ #define ARS_LAST_LAYER -1 /* Structure and defines needed to calculate the internet-like checksum * when the data is splitted in more not adjacent buffers */ #define ARS_MC_INIT 0 #define ARS_MC_UPDATE 1 #define ARS_MC_FINAL 2 struct mc_context { u_int32_t oddbyte_flag; u_int32_t old; u_int8_t oddbyte; u_int8_t pad; }; /* ARS layer info structure */ struct ars_layer_info { char *li_name; /* NULL = unused slot */ int (*li_compiler) (struct ars_packet *pkt, int layer); /* NULL = NOP */ int layer_id; }; /* ARS layer info table */ struct ars_layer_info ars_linfo[ARS_TYPE_SIZE]; /* ARS interface managment structure and defines */ #define ARS_IF_UP (1 << 0) #define ARS_IF_LOOP (1 << 1) #define ARS_IF_IPV4 (1 << 2) #define ARS_IF_IPV6 (1 << 3) #define ARS_IF_MISCONF (1 << 4) #define ARS_IF_MAX_IFACE 16 #define ARS_IF_NAME_SIZE 32 /* iface type are obtained using libpcap to avoid efforts duplication */ struct ars_iface { char if_name[ARS_IF_NAME_SIZE]; int if_mtu; int if_flags; char if_ipv4addr[ARS_INET_ADDRSTRLEN]; char if_ipv6addr[ARS_INET6_ADDRSTRLEN]; }; /* Flags for packet splitting */ #define ARS_SPLIT_FTRUNC (1 << 0) #define ARS_SPLIT_FBADCKSUM (1 << 1) /* More macros */ #define ars_atou(x) strtoul(x, (char **) NULL, 0) /* Prototypes */ int ars_init(struct ars_packet *pkt); int ars_destroy(struct ars_packet *pkt); int ars_nospace(struct ars_packet *pkt); int ars_add_generic(struct ars_packet *pkt, size_t size, int type); void *ars_add_iphdr(struct ars_packet *pkt, int unused); void *ars_add_ipopt(struct ars_packet *pkt, int option); void *ars_add_udphdr(struct ars_packet *pkt, int unused); void *ars_add_tcphdr(struct ars_packet *pkt, int unused); void *ars_add_tcpopt(struct ars_packet *pkt, int option); void *ars_add_icmphdr(struct ars_packet *pkt, int unused); void *ars_add_data(struct ars_packet *pkt, int size); size_t ars_relative_size(struct ars_packet *pkt, int layer_nr); size_t ars_packet_size(struct ars_packet *pkt); u_int16_t ars_cksum(void *vbuf, size_t nbytes); u_int16_t ars_multi_cksum(struct mc_context *c, int op, void *vbuf, size_t nbytes); int ars_compile(struct ars_packet *pkt); int ars_udptcp_cksum(struct ars_packet *pkt, int layer, u_int16_t *sum); int ars_open_rawsocket(struct ars_packet *pkt); int ars_build_packet(struct ars_packet *pkt, unsigned char **packet, size_t *size); int ars_bsd_fix(struct ars_packet *pkt, unsigned char *packet, size_t size); int ars_set_flags(struct ars_packet *pkt, int layer, int flags); int ars_send(int s, struct ars_packet *pkt, struct sockaddr *sa, socklen_t slen); int ars_resolve(struct ars_packet *pkt, u_int32_t *dest, char *hostname); int ars_set_error(struct ars_packet *pkt, char *error); int ars_d_build(struct ars_packet *pkt, char *t); int ars_valid_layer(int layer); int ars_get_iface_list(struct ars_iface *iface, size_t *isize); int ars_get_iface(char *name, struct ars_iface *i); int ars_valid_layer(int layer); int ars_remove_layer(struct ars_packet *pkt, int layer); /* split.c prototypes */ int ars_seems_ip(struct ars_iphdr *ip, size_t size); int ars_guess_ipoff(void *packet, size_t size, int *lhs); int ars_check_ip_cksum(struct ars_iphdr *ip); int ars_check_icmp_cksum(struct ars_icmphdr *icmp, size_t size); int ars_split_packet(void *packet, size_t size, int ipoff, struct ars_packet *pkt); #endif /* _ARS_H */