From dc5e6831b88fa28e141525eec4a0d5267024d3f7 Mon Sep 17 00:00:00 2001 From: Phil Sutter Date: Sun, 9 Oct 2022 13:34:55 +0200 Subject: extensions: libebt_ip: Use guided option parser --- extensions/libebt_ip.c | 199 +++++++++++++++++++------------------------------ extensions/libebt_ip.t | 8 ++ 2 files changed, 84 insertions(+), 123 deletions(-) diff --git a/extensions/libebt_ip.c b/extensions/libebt_ip.c index 97ec4160..350dbcb6 100644 --- a/extensions/libebt_ip.c +++ b/extensions/libebt_ip.c @@ -16,7 +16,6 @@ #include #include #include -#include #include #include #include @@ -24,30 +23,56 @@ #include "libxt_icmp.h" -#define IP_SOURCE '1' -#define IP_DEST '2' -#define IP_EBT_TOS '3' /* include/bits/in.h seems to already define IP_TOS */ -#define IP_PROTO '4' -#define IP_SPORT '5' -#define IP_DPORT '6' -#define IP_EBT_ICMP '7' -#define IP_EBT_IGMP '8' - -static const struct option brip_opts[] = { - { .name = "ip-source", .has_arg = true, .val = IP_SOURCE }, - { .name = "ip-src", .has_arg = true, .val = IP_SOURCE }, - { .name = "ip-destination", .has_arg = true, .val = IP_DEST }, - { .name = "ip-dst", .has_arg = true, .val = IP_DEST }, - { .name = "ip-tos", .has_arg = true, .val = IP_EBT_TOS }, - { .name = "ip-protocol", .has_arg = true, .val = IP_PROTO }, - { .name = "ip-proto", .has_arg = true, .val = IP_PROTO }, - { .name = "ip-source-port", .has_arg = true, .val = IP_SPORT }, - { .name = "ip-sport", .has_arg = true, .val = IP_SPORT }, - { .name = "ip-destination-port",.has_arg = true, .val = IP_DPORT }, - { .name = "ip-dport", .has_arg = true, .val = IP_DPORT }, - { .name = "ip-icmp-type", .has_arg = true, .val = IP_EBT_ICMP }, - { .name = "ip-igmp-type", .has_arg = true, .val = IP_EBT_IGMP }, - XT_GETOPT_TABLEEND, +/* must correspond to the bit position in EBT_IP6_* defines */ +enum { + O_SOURCE = 0, + O_DEST, + O_TOS, + O_PROTO, + O_SPORT, + O_DPORT, + O_ICMP, + O_IGMP, + F_PORT = 1 << O_ICMP | 1 << O_IGMP, + F_ICMP = 1 << O_SPORT | 1 << O_DPORT | 1 << O_IGMP, + F_IGMP = 1 << O_SPORT | 1 << O_DPORT | 1 << O_ICMP, +}; + +static const struct xt_option_entry brip_opts[] = { + { .name = "ip-source", .id = O_SOURCE, .type = XTTYPE_HOSTMASK, + .flags = XTOPT_INVERT }, + { .name = "ip-src", .id = O_SOURCE, .type = XTTYPE_HOSTMASK, + .flags = XTOPT_INVERT }, + { .name = "ip-destination", .id = O_DEST, .type = XTTYPE_HOSTMASK, + .flags = XTOPT_INVERT }, + { .name = "ip-dst", .id = O_DEST, .type = XTTYPE_HOSTMASK, + .flags = XTOPT_INVERT }, + { .name = "ip-tos", .id = O_TOS, .type = XTTYPE_UINT8, + .flags = XTOPT_INVERT | XTOPT_PUT, + XTOPT_POINTER(struct ebt_ip_info, tos) }, + { .name = "ip-protocol", .id = O_PROTO, .type = XTTYPE_PROTOCOL, + .flags = XTOPT_INVERT | XTOPT_PUT, + XTOPT_POINTER(struct ebt_ip_info, protocol) }, + { .name = "ip-proto", .id = O_PROTO, .type = XTTYPE_PROTOCOL, + .flags = XTOPT_INVERT | XTOPT_PUT, + XTOPT_POINTER(struct ebt_ip_info, protocol) }, + { .name = "ip-source-port", .id = O_SPORT, .type = XTTYPE_PORTRC, + .excl = F_PORT, .flags = XTOPT_INVERT | XTOPT_PUT, + XTOPT_POINTER(struct ebt_ip_info, sport) }, + { .name = "ip-sport", .id = O_SPORT, .type = XTTYPE_PORTRC, + .excl = F_PORT, .flags = XTOPT_INVERT | XTOPT_PUT, + XTOPT_POINTER(struct ebt_ip_info, sport) }, + { .name = "ip-destination-port",.id = O_DPORT, .type = XTTYPE_PORTRC, + .excl = F_PORT, .flags = XTOPT_INVERT | XTOPT_PUT, + XTOPT_POINTER(struct ebt_ip_info, dport) }, + { .name = "ip-dport", .id = O_DPORT, .type = XTTYPE_PORTRC, + .excl = F_PORT, .flags = XTOPT_INVERT | XTOPT_PUT, + XTOPT_POINTER(struct ebt_ip_info, dport) }, + { .name = "ip-icmp-type", .id = O_ICMP, .type = XTTYPE_STRING, + .excl = F_ICMP, .flags = XTOPT_INVERT }, + { .name = "ip-igmp-type", .id = O_IGMP, .type = XTTYPE_STRING, + .excl = F_IGMP, .flags = XTOPT_INVERT }, + XTOPT_TABLEEND, }; static void brip_print_help(void) @@ -69,30 +94,6 @@ static void brip_print_help(void) xt_print_icmp_types(igmp_types, ARRAY_SIZE(igmp_types)); } -static void -parse_port_range(const char *protocol, const char *portstring, uint16_t *ports) -{ - char *buffer; - char *cp; - - buffer = xtables_strdup(portstring); - - if ((cp = strchr(buffer, ':')) == NULL) - ports[0] = ports[1] = xtables_parse_port(buffer, NULL); - else { - *cp = '\0'; - cp++; - - ports[0] = buffer[0] ? xtables_parse_port(buffer, NULL) : 0; - ports[1] = cp[0] ? xtables_parse_port(cp, NULL) : 0xFFFF; - - if (ports[0] > ports[1]) - xtables_error(PARAMETER_PROBLEM, - "invalid portrange (min > max)"); - } - free(buffer); -} - /* original code from ebtables: useful_functions.c */ static void print_icmp_code(uint8_t *code) { @@ -130,86 +131,38 @@ static void ebt_print_icmp_type(const struct xt_icmp_names *codes, print_icmp_code(code); } -static int -brip_parse(int c, char **argv, int invert, unsigned int *flags, - const void *entry, struct xt_entry_match **match) +static void brip_parse(struct xt_option_call *cb) { - struct ebt_ip_info *info = (struct ebt_ip_info *)(*match)->data; - struct in_addr *ipaddr, ipmask; - unsigned int ipnr; - - switch (c) { - case IP_SOURCE: - if (invert) - info->invflags |= EBT_IP_SOURCE; - xtables_ipparse_any(optarg, &ipaddr, &ipmask, &ipnr); - info->saddr = ipaddr->s_addr; - info->smsk = ipmask.s_addr; - free(ipaddr); - info->bitmask |= EBT_IP_SOURCE; - break; - case IP_DEST: - if (invert) - info->invflags |= EBT_IP_DEST; - xtables_ipparse_any(optarg, &ipaddr, &ipmask, &ipnr); - info->daddr = ipaddr->s_addr; - info->dmsk = ipmask.s_addr; - free(ipaddr); - info->bitmask |= EBT_IP_DEST; - break; - case IP_SPORT: - if (invert) - info->invflags |= EBT_IP_SPORT; - parse_port_range(NULL, optarg, info->sport); - info->bitmask |= EBT_IP_SPORT; - break; - case IP_DPORT: - if (invert) - info->invflags |= EBT_IP_DPORT; - parse_port_range(NULL, optarg, info->dport); - info->bitmask |= EBT_IP_DPORT; - break; - case IP_EBT_ICMP: - if (invert) - info->invflags |= EBT_IP_ICMP; - ebt_parse_icmp(optarg, info->icmp_type, info->icmp_code); - info->bitmask |= EBT_IP_ICMP; + struct ebt_ip_info *info = cb->data; + + xtables_option_parse(cb); + + info->bitmask |= 1 << cb->entry->id; + info->invflags |= cb->invert ? 1 << cb->entry->id : 0; + + switch (cb->entry->id) { + case O_SOURCE: + cb->val.haddr.all[0] &= cb->val.hmask.all[0]; + info->saddr = cb->val.haddr.ip; + info->smsk = cb->val.hmask.ip; break; - case IP_EBT_IGMP: - if (invert) - info->invflags |= EBT_IP_IGMP; - ebt_parse_igmp(optarg, info->igmp_type); - info->bitmask |= EBT_IP_IGMP; + case O_DEST: + cb->val.haddr.all[0] &= cb->val.hmask.all[0]; + info->daddr = cb->val.haddr.ip; + info->dmsk = cb->val.hmask.ip; break; - case IP_EBT_TOS: { - uintmax_t tosvalue; - - if (invert) - info->invflags |= EBT_IP_TOS; - if (!xtables_strtoul(optarg, NULL, &tosvalue, 0, 255)) - xtables_error(PARAMETER_PROBLEM, - "Problem with specified IP tos"); - info->tos = tosvalue; - info->bitmask |= EBT_IP_TOS; - } + case O_ICMP: + ebt_parse_icmp(cb->arg, info->icmp_type, info->icmp_code); break; - case IP_PROTO: - if (invert) - info->invflags |= EBT_IP_PROTO; - info->protocol = xtables_parse_protocol(optarg); - info->bitmask |= EBT_IP_PROTO; + case O_IGMP: + ebt_parse_igmp(cb->arg, info->igmp_type); break; - default: - return 0; } - - *flags |= info->bitmask; - return 1; } -static void brip_final_check(unsigned int flags) +static void brip_final_check(struct xt_fcheck_call *fc) { - if (!flags) + if (!fc->xflags) xtables_error(PARAMETER_PROBLEM, "You must specify proper arguments"); } @@ -496,11 +449,11 @@ static struct xtables_match brip_match = { .size = XT_ALIGN(sizeof(struct ebt_ip_info)), .userspacesize = XT_ALIGN(sizeof(struct ebt_ip_info)), .help = brip_print_help, - .parse = brip_parse, - .final_check = brip_final_check, + .x6_parse = brip_parse, + .x6_fcheck = brip_final_check, .print = brip_print, .xlate = brip_xlate, - .extra_opts = brip_opts, + .x6_options = brip_opts, }; void _init(void) diff --git a/extensions/libebt_ip.t b/extensions/libebt_ip.t index 8be5dfbb..f6012df4 100644 --- a/extensions/libebt_ip.t +++ b/extensions/libebt_ip.t @@ -1,13 +1,21 @@ :INPUT,FORWARD,OUTPUT -p ip --ip-src ! 192.168.0.0/24 -j ACCEPT;-p IPv4 --ip-src ! 192.168.0.0/24 -j ACCEPT;OK -p IPv4 --ip-dst 10.0.0.1;=;OK +-p IPv4 --ip-dst ! 10.0.0.1;=;OK -p IPv4 --ip-tos 0xFF;=;OK -p IPv4 --ip-tos ! 0xFF;=;OK -p IPv4 --ip-proto tcp --ip-dport 22;=;OK -p IPv4 --ip-proto udp --ip-sport 1024:65535;=;OK -p IPv4 --ip-proto 253;=;OK +-p IPv4 --ip-proto ! 253;=;OK -p IPv4 --ip-proto icmp --ip-icmp-type echo-request;=;OK -p IPv4 --ip-proto icmp --ip-icmp-type 1/1;=;OK -p ip --ip-protocol icmp --ip-icmp-type ! 1:10;-p IPv4 --ip-proto icmp --ip-icmp-type ! 1:10/0:255 -j CONTINUE;OK --ip-proto icmp --ip-icmp-type 1/1;=;FAIL ! -p ip --ip-proto icmp --ip-icmp-type 1/1;=;FAIL +! -p ip --ip-proto tcp --ip-sport 22 --ip-icmp-type echo-reply;;FAIL +! -p ip --ip-proto tcp --ip-sport 22 --ip-igmp-type membership-query;;FAIL +! -p ip --ip-proto tcp --ip-dport 22 --ip-icmp-type echo-reply;;FAIL +! -p ip --ip-proto tcp --ip-dport 22 --ip-igmp-type membership-query;;FAIL +! -p ip --ip-proto icmp --ip-icmp-type echo-reply --ip-igmp-type membership-query;;FAIL +-p IPv4 --ip-proto icmp --ip-icmp-type ! echo-reply;=;OK -- cgit v1.2.3