-/*
- * libxt_owner - iptables addon for xt_owner
- *
- * Copyright © CC Computer Consultants GmbH, 2007 - 2008
- * Jan Engelhardt <jengelh@computergmbh.de>
- */
-#include <getopt.h>
-#include <grp.h>
-#include <netdb.h>
-#include <pwd.h>
-#include <stdbool.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include <xtables.h>
-#include <linux/netfilter/xt_owner.h>
-#include <linux/netfilter_ipv4/ipt_owner.h>
-#include <linux/netfilter_ipv6/ip6t_owner.h>
-
-enum {
- FLAG_UID_OWNER = 1 << 0,
- FLAG_GID_OWNER = 1 << 1,
- FLAG_SOCKET_EXISTS = 1 << 2,
- FLAG_PID_OWNER = 1 << 3,
- FLAG_SID_OWNER = 1 << 4,
- FLAG_COMM = 1 << 5,
-};
-
-static void owner_mt_help_v0(void)
-{
-#ifdef IPT_OWNER_COMM
- printf(
-"owner match options:\n"
-"[!] --uid-owner userid Match local UID\n"
-"[!] --gid-owner groupid Match local GID\n"
-"[!] --pid-owner processid Match local PID\n"
-"[!] --sid-owner sessionid Match local SID\n"
-"[!] --cmd-owner name Match local command name\n"
-"NOTE: PID, SID and command matching are broken on SMP\n");
-#else
- printf(
-"owner match options:\n"
-"[!] --uid-owner userid Match local UID\n"
-"[!] --gid-owner groupid Match local GID\n"
-"[!] --pid-owner processid Match local PID\n"
-"[!] --sid-owner sessionid Match local SID\n"
-"NOTE: PID and SID matching are broken on SMP\n");
-#endif /* IPT_OWNER_COMM */
-}
-
-static void owner_mt6_help_v0(void)
-{
- printf(
-"owner match options:\n"
-"[!] --uid-owner userid Match local UID\n"
-"[!] --gid-owner groupid Match local GID\n"
-"[!] --pid-owner processid Match local PID\n"
-"[!] --sid-owner sessionid Match local SID\n"
-"NOTE: PID and SID matching are broken on SMP\n");
-}
-
-static void owner_mt_help(void)
-{
- printf(
-"owner match options:\n"
-"[!] --uid-owner userid[-userid] Match local UID\n"
-"[!] --gid-owner groupid[-groupid] Match local GID\n"
-"[!] --socket-exists Match if socket exists\n");
-}
-
-static const struct option owner_mt_opts_v0[] = {
- {.name = "uid-owner", .has_arg = true, .val = 'u'},
- {.name = "gid-owner", .has_arg = true, .val = 'g'},
- {.name = "pid-owner", .has_arg = true, .val = 'p'},
- {.name = "sid-owner", .has_arg = true, .val = 's'},
-#ifdef IPT_OWNER_COMM
- {.name = "cmd-owner", .has_arg = true, .val = 'c'},
-#endif
- { .name = NULL }
-};
-
-static const struct option owner_mt6_opts_v0[] = {
- {.name = "uid-owner", .has_arg = true, .val = 'u'},
- {.name = "gid-owner", .has_arg = true, .val = 'g'},
- {.name = "pid-owner", .has_arg = true, .val = 'p'},
- {.name = "sid-owner", .has_arg = true, .val = 's'},
- { .name = NULL }
-};
-
-static const struct option owner_mt_opts[] = {
- {.name = "uid-owner", .has_arg = true, .val = 'u'},
- {.name = "gid-owner", .has_arg = true, .val = 'g'},
- {.name = "socket-exists", .has_arg = false, .val = 'k'},
- { .name = NULL }
-};
-
-static int
-owner_mt_parse_v0(int c, char **argv, int invert, unsigned int *flags,
- const void *entry, struct xt_entry_match **match)
-{
- struct ipt_owner_info *info = (void *)(*match)->data;
- struct passwd *pwd;
- struct group *grp;
- unsigned int id;
-
- switch (c) {
- case 'u':
- param_act(P_ONLY_ONCE, "owner", "--uid-owner", *flags & FLAG_UID_OWNER);
- if ((pwd = getpwnam(optarg)) != NULL)
- id = pwd->pw_uid;
- else if (!strtonum(optarg, NULL, &id, 0, ~(uid_t)0))
- param_act(P_BAD_VALUE, "owner", "--uid-owner", optarg);
- if (invert)
- info->invert |= IPT_OWNER_UID;
- info->match |= IPT_OWNER_UID;
- info->uid = id;
- *flags |= FLAG_UID_OWNER;
- return true;
-
- case 'g':
- param_act(P_ONLY_ONCE, "owner", "--gid-owner", *flags & FLAG_GID_OWNER);
- if ((grp = getgrnam(optarg)) != NULL)
- id = grp->gr_gid;
- else if (!strtonum(optarg, NULL, &id, 0, ~(gid_t)0))
- param_act(P_BAD_VALUE, "owner", "--gid-owner", optarg);
- if (invert)
- info->invert |= IPT_OWNER_GID;
- info->match |= IPT_OWNER_GID;
- info->gid = id;
- *flags |= FLAG_GID_OWNER;
- return true;
-
- case 'p':
- param_act(P_ONLY_ONCE, "owner", "--pid-owner", *flags & FLAG_PID_OWNER);
- if (!strtonum(optarg, NULL, &id, 0, INT_MAX))
- param_act(P_BAD_VALUE, "owner", "--pid-owner", optarg);
- if (invert)
- info->invert |= IPT_OWNER_PID;
- info->match |= IPT_OWNER_PID;
- info->pid = id;
- *flags |= FLAG_PID_OWNER;
- return true;
-
- case 's':
- param_act(P_ONLY_ONCE, "owner", "--sid-owner", *flags & FLAG_SID_OWNER);
- if (!strtonum(optarg, NULL, &id, 0, INT_MAX))
- param_act(P_BAD_VALUE, "owner", "--sid-value", optarg);
- if (invert)
- info->invert |= IPT_OWNER_SID;
- info->match |= IPT_OWNER_SID;
- info->sid = id;
- *flags |= FLAG_SID_OWNER;
- return true;
-
-#ifdef IPT_OWNER_COMM
- case 'c':
- param_act(P_ONLY_ONCE, "owner", "--cmd-owner", *flags & FLAG_COMM);
- if (strlen(optarg) > sizeof(info->comm))
- exit_error(PARAMETER_PROBLEM, "owner match: command "
- "\"%s\" too long, max. %zu characters",
- optarg, sizeof(info->comm));
-
- info->comm[sizeof(info->comm)-1] = '\0';
- strncpy(info->comm, optarg, sizeof(info->comm));
-
- if (invert)
- info->invert |= IPT_OWNER_COMM;
- info->match |= IPT_OWNER_COMM;
- *flags |= FLAG_COMM;
- return true;
-#endif
- }
- return false;
-}
-
-static int
-owner_mt6_parse_v0(int c, char **argv, int invert, unsigned int *flags,
- const void *entry, struct xt_entry_match **match)
-{
- struct ip6t_owner_info *info = (void *)(*match)->data;
- struct passwd *pwd;
- struct group *grp;
- unsigned int id;
-
- switch (c) {
- case 'u':
- param_act(P_ONLY_ONCE, "owner", "--uid-owner",
- *flags & FLAG_UID_OWNER);
- if ((pwd = getpwnam(optarg)) != NULL)
- id = pwd->pw_uid;
- else if (!strtonum(optarg, NULL, &id, 0, ~(uid_t)0))
- param_act(P_BAD_VALUE, "owner", "--uid-owner", optarg);
- if (invert)
- info->invert |= IP6T_OWNER_UID;
- info->match |= IP6T_OWNER_UID;
- info->uid = id;
- *flags |= FLAG_UID_OWNER;
- return true;
-
- case 'g':
- param_act(P_ONLY_ONCE, "owner", "--gid-owner",
- *flags & FLAG_GID_OWNER);
- if ((grp = getgrnam(optarg)) != NULL)
- id = grp->gr_gid;
- else if (!strtonum(optarg, NULL, &id, 0, ~(gid_t)0))
- param_act(P_BAD_VALUE, "owner", "--gid-owner", optarg);
- if (invert)
- info->invert |= IP6T_OWNER_GID;
- info->match |= IP6T_OWNER_GID;
- info->gid = id;
- *flags |= FLAG_GID_OWNER;
- return true;
-
- case 'p':
- param_act(P_ONLY_ONCE, "owner", "--pid-owner",
- *flags & FLAG_PID_OWNER);
- if (!strtonum(optarg, NULL, &id, 0, INT_MAX))
- param_act(P_BAD_VALUE, "owner", "--pid-owner", optarg);
- if (invert)
- info->invert |= IP6T_OWNER_PID;
- info->match |= IP6T_OWNER_PID;
- info->pid = id;
- *flags |= FLAG_PID_OWNER;
- return true;
-
- case 's':
- param_act(P_ONLY_ONCE, "owner", "--sid-owner",
- *flags & FLAG_SID_OWNER);
- if (!strtonum(optarg, NULL, &id, 0, INT_MAX))
- param_act(P_BAD_VALUE, "owner", "--sid-owner", optarg);
- if (invert)
- info->invert |= IP6T_OWNER_SID;
- info->match |= IP6T_OWNER_SID;
- info->sid = id;
- *flags |= FLAG_SID_OWNER;
- return true;
- }
- return false;
-}
-
-static void owner_parse_range(const char *s, unsigned int *from,
- unsigned int *to, const char *opt)
-{
- char *end;
-
- /* 4294967295 is reserved, so subtract one from ~0 */
- if (!strtonum(s, &end, from, 0, (~(uid_t)0) - 1))
- param_act(P_BAD_VALUE, "owner", opt, s);
- *to = *from;
- if (*end == '-' || *end == ':')
- if (!strtonum(end + 1, &end, to, 0, (~(uid_t)0) - 1))
- param_act(P_BAD_VALUE, "owner", opt, s);
- if (*end != '\0')
- param_act(P_BAD_VALUE, "owner", opt, s);
-}
-
-static int owner_mt_parse(int c, char **argv, int invert, unsigned int *flags,
- const void *entry, struct xt_entry_match **match)
-{
- struct xt_owner_match_info *info = (void *)(*match)->data;
- struct passwd *pwd;
- struct group *grp;
- unsigned int from, to;
-
- switch (c) {
- case 'u':
- param_act(P_ONLY_ONCE, "owner", "--uid-owner",
- *flags & FLAG_UID_OWNER);
- if ((pwd = getpwnam(optarg)) != NULL)
- from = to = pwd->pw_uid;
- else
- owner_parse_range(optarg, &from, &to, "--uid-owner");
- if (invert)
- info->invert |= XT_OWNER_UID;
- info->match |= XT_OWNER_UID;
- info->uid_min = from;
- info->uid_max = to;
- *flags |= FLAG_UID_OWNER;
- return true;
-
- case 'g':
- param_act(P_ONLY_ONCE, "owner", "--gid-owner",
- *flags & FLAG_GID_OWNER);
- if ((grp = getgrnam(optarg)) != NULL)
- from = to = grp->gr_gid;
- else
- owner_parse_range(optarg, &from, &to, "--gid-owner");
- if (invert)
- info->invert |= XT_OWNER_GID;
- info->match |= XT_OWNER_GID;
- info->gid_min = from;
- info->gid_max = to;
- *flags |= FLAG_GID_OWNER;
- return true;
-
- case 'k':
- param_act(P_ONLY_ONCE, "owner", "--socket-exists",
- *flags & FLAG_SOCKET_EXISTS);
- if (invert)
- info->invert |= XT_OWNER_SOCKET;
- info->match |= XT_OWNER_SOCKET;
- *flags |= FLAG_SOCKET_EXISTS;
- return true;
-
- }
- return false;
-}
-
-static void owner_mt_check(unsigned int flags)
-{
- if (flags == 0)
- exit_error(PARAMETER_PROBLEM, "owner: At least one of "
- "--uid-owner, --gid-owner or --socket-exists "
- "is required");
-}
-
-static void
-owner_mt_print_item_v0(const struct ipt_owner_info *info, const char *label,
- u_int8_t flag, bool numeric)
-{
- if (!(info->match & flag))
- return;
- if (info->invert & flag)
- printf("! ");
- printf(label);
-
- switch (info->match & flag) {
- case IPT_OWNER_UID:
- if (!numeric) {
- struct passwd *pwd = getpwuid(info->uid);
-
- if (pwd != NULL && pwd->pw_name != NULL) {
- printf("%s ", pwd->pw_name);
- break;
- }
- }
- printf("%u ", (unsigned int)info->uid);
- break;
-
- case IPT_OWNER_GID:
- if (!numeric) {
- struct group *grp = getgrgid(info->gid);
-
- if (grp != NULL && grp->gr_name != NULL) {
- printf("%s ", grp->gr_name);
- break;
- }
- }
- printf("%u ", (unsigned int)info->gid);
- break;
-
- case IPT_OWNER_PID:
- printf("%u ", (unsigned int)info->pid);
- break;
-
- case IPT_OWNER_SID:
- printf("%u ", (unsigned int)info->sid);
- break;
-
-#ifdef IPT_OWNER_COMM
- case IPT_OWNER_COMM:
- printf("%.*s ", (int)sizeof(info->comm), info->comm);
- break;
-#endif
- }
-}
-
-static void
-owner_mt6_print_item_v0(const struct ip6t_owner_info *info, const char *label,
- u_int8_t flag, bool numeric)
-{
- if (!(info->match & flag))
- return;
- if (info->invert & flag)
- printf("! ");
- printf(label);
-
- switch (info->match & flag) {
- case IP6T_OWNER_UID:
- if (!numeric) {
- struct passwd *pwd = getpwuid(info->uid);
-
- if (pwd != NULL && pwd->pw_name != NULL) {
- printf("%s ", pwd->pw_name);
- break;
- }
- }
- printf("%u ", (unsigned int)info->uid);
- break;
-
- case IP6T_OWNER_GID:
- if (!numeric) {
- struct group *grp = getgrgid(info->gid);
-
- if (grp != NULL && grp->gr_name != NULL) {
- printf("%s ", grp->gr_name);
- break;
- }
- }
- printf("%u ", (unsigned int)info->gid);
- break;
-
- case IP6T_OWNER_PID:
- printf("%u ", (unsigned int)info->pid);
- break;
-
- case IP6T_OWNER_SID:
- printf("%u ", (unsigned int)info->sid);
- break;
- }
-}
-
-static void
-owner_mt_print_item(const struct xt_owner_match_info *info, const char *label,
- u_int8_t flag, bool numeric)
-{
- if (!(info->match & flag))
- return;
- if (info->invert & flag)
- printf("! ");
- printf("%s ", label);
-
- switch (info->match & flag) {
- case XT_OWNER_UID:
- if (info->uid_min != info->uid_max) {
- printf("%u-%u ", (unsigned int)info->uid_min,
- (unsigned int)info->uid_max);
- break;
- } else if (!numeric) {
- const struct passwd *pwd = getpwuid(info->uid_min);
-
- if (pwd != NULL && pwd->pw_name != NULL) {
- printf("%s ", pwd->pw_name);
- break;
- }
- }
- printf("%u ", (unsigned int)info->uid_min);
- break;
-
- case XT_OWNER_GID:
- if (info->gid_min != info->gid_max) {
- printf("%u-%u ", (unsigned int)info->gid_min,
- (unsigned int)info->gid_max);
- break;
- } else if (!numeric) {
- const struct group *grp = getgrgid(info->gid_min);
-
- if (grp != NULL && grp->gr_name != NULL) {
- printf("%s ", grp->gr_name);
- break;
- }
- }
- printf("%u ", (unsigned int)info->gid_min);
- break;
- }
-}
-
-static void
-owner_mt_print_v0(const void *ip, const struct xt_entry_match *match,
- int numeric)
-{
- const struct ipt_owner_info *info = (void *)match->data;
-
- owner_mt_print_item_v0(info, "owner UID match", IPT_OWNER_UID, numeric);
- owner_mt_print_item_v0(info, "owner GID match", IPT_OWNER_GID, numeric);
- owner_mt_print_item_v0(info, "owner PID match", IPT_OWNER_PID, numeric);
- owner_mt_print_item_v0(info, "owner SID match", IPT_OWNER_SID, numeric);
-#ifdef IPT_OWNER_COMM
- owner_mt_print_item_v0(info, "owner CMD match", IPT_OWNER_COMM, numeric);
-#endif
-}
-
-static void
-owner_mt6_print_v0(const void *ip, const struct xt_entry_match *match,
- int numeric)
-{
- const struct ip6t_owner_info *info = (void *)match->data;
-
- owner_mt6_print_item_v0(info, "owner UID match", IPT_OWNER_UID, numeric);
- owner_mt6_print_item_v0(info, "owner GID match", IPT_OWNER_GID, numeric);
- owner_mt6_print_item_v0(info, "owner PID match", IPT_OWNER_PID, numeric);
- owner_mt6_print_item_v0(info, "owner SID match", IPT_OWNER_SID, numeric);
-}
-
-static void owner_mt_print(const void *ip, const struct xt_entry_match *match,
- int numeric)
-{
- const struct xt_owner_match_info *info = (void *)match->data;
-
- owner_mt_print_item(info, "owner socket exists", XT_OWNER_SOCKET, numeric);
- owner_mt_print_item(info, "owner UID match", XT_OWNER_UID, numeric);
- owner_mt_print_item(info, "owner GID match", XT_OWNER_GID, numeric);
-}
-
-static void
-owner_mt_save_v0(const void *ip, const struct xt_entry_match *match)
-{
- const struct ipt_owner_info *info = (void *)match->data;
-
- owner_mt_print_item_v0(info, "--uid-owner", IPT_OWNER_UID, true);
- owner_mt_print_item_v0(info, "--gid-owner", IPT_OWNER_GID, true);
- owner_mt_print_item_v0(info, "--pid-owner", IPT_OWNER_PID, true);
- owner_mt_print_item_v0(info, "--sid-owner", IPT_OWNER_SID, true);
-#ifdef IPT_OWNER_COMM
- owner_mt_print_item_v0(info, "--cmd-owner", IPT_OWNER_COMM, true);
-#endif
-}
-
-static void
-owner_mt6_save_v0(const void *ip, const struct xt_entry_match *match)
-{
- const struct ip6t_owner_info *info = (void *)match->data;
-
- owner_mt6_print_item_v0(info, "--uid-owner", IPT_OWNER_UID, true);
- owner_mt6_print_item_v0(info, "--gid-owner", IPT_OWNER_GID, true);
- owner_mt6_print_item_v0(info, "--pid-owner", IPT_OWNER_PID, true);
- owner_mt6_print_item_v0(info, "--sid-owner", IPT_OWNER_SID, true);
-}
-
-static void owner_mt_save(const void *ip, const struct xt_entry_match *match)
-{
- const struct xt_owner_match_info *info = (void *)match->data;
-
- owner_mt_print_item(info, "--socket-exists", XT_OWNER_SOCKET, false);
- owner_mt_print_item(info, "--uid-owner", XT_OWNER_UID, false);
- owner_mt_print_item(info, "--gid-owner", XT_OWNER_GID, false);
-}
-
-static struct xtables_match owner_mt_reg_v0 = {
- .version = XTABLES_VERSION,
- .name = "owner",
- .revision = 0,
- .family = AF_INET,
- .size = XT_ALIGN(sizeof(struct ipt_owner_info)),
- .userspacesize = XT_ALIGN(sizeof(struct ipt_owner_info)),
- .help = owner_mt_help_v0,
- .parse = owner_mt_parse_v0,
- .final_check = owner_mt_check,
- .print = owner_mt_print_v0,
- .save = owner_mt_save_v0,
- .extra_opts = owner_mt_opts_v0,
-};
-
-static struct xtables_match owner_mt6_reg_v0 = {
- .version = XTABLES_VERSION,
- .name = "owner",
- .revision = 0,
- .family = AF_INET6,
- .size = XT_ALIGN(sizeof(struct ip6t_owner_info)),
- .userspacesize = XT_ALIGN(sizeof(struct ip6t_owner_info)),
- .help = owner_mt6_help_v0,
- .parse = owner_mt6_parse_v0,
- .final_check = owner_mt_check,
- .print = owner_mt6_print_v0,
- .save = owner_mt6_save_v0,
- .extra_opts = owner_mt6_opts_v0,
-};
-
-static struct xtables_match owner_mt_reg = {
- .version = XTABLES_VERSION,
- .name = "owner",
- .revision = 1,
- .family = AF_INET,
- .size = XT_ALIGN(sizeof(struct xt_owner_match_info)),
- .userspacesize = XT_ALIGN(sizeof(struct xt_owner_match_info)),
- .help = owner_mt_help,
- .parse = owner_mt_parse,
- .final_check = owner_mt_check,
- .print = owner_mt_print,
- .save = owner_mt_save,
- .extra_opts = owner_mt_opts,
-};
-
-static struct xtables_match owner_mt6_reg = {
- .version = XTABLES_VERSION,
- .name = "owner",
- .revision = 1,
- .family = AF_INET6,
- .size = XT_ALIGN(sizeof(struct xt_owner_match_info)),
- .userspacesize = XT_ALIGN(sizeof(struct xt_owner_match_info)),
- .help = owner_mt_help,
- .parse = owner_mt_parse,
- .final_check = owner_mt_check,
- .print = owner_mt_print,
- .save = owner_mt_save,
- .extra_opts = owner_mt_opts,
-};
-
-void _init(void)
-{
- xtables_register_match(&owner_mt_reg_v0);
- xtables_register_match(&owner_mt6_reg_v0);
- xtables_register_match(&owner_mt_reg);
- xtables_register_match(&owner_mt6_reg);
-}