1 #ifndef _LIBXT_SET_H
2 #define _LIBXT_SET_H
3 
4 #include <unistd.h>
5 #include <fcntl.h>
6 #include <sys/types.h>
7 #include <sys/socket.h>
8 #include <errno.h>
9 #include "../iptables/xshared.h"
10 
11 #ifdef DEBUG
12 #define DEBUGP(x, args...) fprintf(stderr, x , ## args)
13 #else
14 #define DEBUGP(x, args...)
15 #endif
16 
17 static int
get_version(unsigned * version)18 get_version(unsigned *version)
19 {
20 	int res, sockfd = socket(AF_INET, SOCK_RAW, IPPROTO_RAW);
21 	struct ip_set_req_version req_version;
22 	socklen_t size = sizeof(req_version);
23 
24 	if (sockfd < 0)
25 		xtables_error(OTHER_PROBLEM,
26 			      "Can't open socket to ipset.\n");
27 
28 	if (fcntl(sockfd, F_SETFD, FD_CLOEXEC) == -1) {
29 		xtables_error(OTHER_PROBLEM,
30 			      "Could not set close on exec: %s\n",
31 			      strerror(errno));
32 	}
33 
34 	req_version.op = IP_SET_OP_VERSION;
35 	res = getsockopt(sockfd, SOL_IP, SO_IP_SET, &req_version, &size);
36 	if (res != 0)
37 		xtables_error(OTHER_PROBLEM,
38 			      "Kernel module xt_set is not loaded in.\n");
39 
40 	*version = req_version.version;
41 
42 	return sockfd;
43 }
44 
45 static void
get_set_byid(char * setname,ip_set_id_t idx)46 get_set_byid(char *setname, ip_set_id_t idx)
47 {
48 	struct ip_set_req_get_set req;
49 	socklen_t size = sizeof(struct ip_set_req_get_set);
50 	int res, sockfd;
51 
52 	sockfd = get_version(&req.version);
53 	req.op = IP_SET_OP_GET_BYINDEX;
54 	req.set.index = idx;
55 	res = getsockopt(sockfd, SOL_IP, SO_IP_SET, &req, &size);
56 	close(sockfd);
57 
58 	if (res != 0)
59 		xtables_error(OTHER_PROBLEM,
60 			"Problem when communicating with ipset, errno=%d.\n",
61 			errno);
62 	if (size != sizeof(struct ip_set_req_get_set))
63 		xtables_error(OTHER_PROBLEM,
64 			"Incorrect return size from kernel during ipset lookup, "
65 			"(want %zu, got %zu)\n",
66 			sizeof(struct ip_set_req_get_set), (size_t)size);
67 	if (req.set.name[0] == '\0')
68 		xtables_error(PARAMETER_PROBLEM,
69 			"Set with index %i in kernel doesn't exist.\n", idx);
70 
71 	strncpy(setname, req.set.name, IPSET_MAXNAMELEN);
72 }
73 
74 static void
get_set_byname_only(const char * setname,struct xt_set_info * info,int sockfd,unsigned int version)75 get_set_byname_only(const char *setname, struct xt_set_info *info,
76 		    int sockfd, unsigned int version)
77 {
78 	struct ip_set_req_get_set req = { .version = version };
79 	socklen_t size = sizeof(struct ip_set_req_get_set);
80 	int res;
81 
82 	req.op = IP_SET_OP_GET_BYNAME;
83 	strncpy(req.set.name, setname, IPSET_MAXNAMELEN);
84 	req.set.name[IPSET_MAXNAMELEN - 1] = '\0';
85 	res = getsockopt(sockfd, SOL_IP, SO_IP_SET, &req, &size);
86 	close(sockfd);
87 
88 	if (res != 0)
89 		xtables_error(OTHER_PROBLEM,
90 			"Problem when communicating with ipset, errno=%d.\n",
91 			errno);
92 	if (size != sizeof(struct ip_set_req_get_set))
93 		xtables_error(OTHER_PROBLEM,
94 			"Incorrect return size from kernel during ipset lookup, "
95 			"(want %zu, got %zu)\n",
96 			sizeof(struct ip_set_req_get_set), (size_t)size);
97 	if (req.set.index == IPSET_INVALID_ID)
98 		xtables_error(PARAMETER_PROBLEM,
99 			      "Set %s doesn't exist.\n", setname);
100 
101 	info->index = req.set.index;
102 }
103 
104 static void
get_set_byname(const char * setname,struct xt_set_info * info)105 get_set_byname(const char *setname, struct xt_set_info *info)
106 {
107 	struct ip_set_req_get_set_family req;
108 	socklen_t size = sizeof(struct ip_set_req_get_set_family);
109 	int res, sockfd, version;
110 
111 	sockfd = get_version(&req.version);
112 	version = req.version;
113 	req.op = IP_SET_OP_GET_FNAME;
114 	strncpy(req.set.name, setname, IPSET_MAXNAMELEN);
115 	req.set.name[IPSET_MAXNAMELEN - 1] = '\0';
116 	res = getsockopt(sockfd, SOL_IP, SO_IP_SET, &req, &size);
117 
118 	if (res != 0 && errno == EBADMSG)
119 		/* Backward compatibility */
120 		return get_set_byname_only(setname, info, sockfd, version);
121 
122 	close(sockfd);
123 	if (res != 0)
124 		xtables_error(OTHER_PROBLEM,
125 			"Problem when communicating with ipset, errno=%d.\n",
126 			errno);
127 	if (size != sizeof(struct ip_set_req_get_set_family))
128 		xtables_error(OTHER_PROBLEM,
129 			"Incorrect return size from kernel during ipset lookup, "
130 			"(want %zu, got %zu)\n",
131 			sizeof(struct ip_set_req_get_set_family),
132 			(size_t)size);
133 	if (req.set.index == IPSET_INVALID_ID)
134 		xtables_error(PARAMETER_PROBLEM,
135 			      "Set %s doesn't exist.\n", setname);
136 	if (!(req.family == afinfo->family ||
137 	      req.family == NFPROTO_UNSPEC))
138 		xtables_error(PARAMETER_PROBLEM,
139 			      "The protocol family of set %s is %s, "
140 			      "which is not applicable.\n",
141 			      setname,
142 			      req.family == NFPROTO_IPV4 ? "IPv4" : "IPv6");
143 
144 	info->index = req.set.index;
145 }
146 
147 static void
parse_dirs_v0(const char * opt_arg,struct xt_set_info_v0 * info)148 parse_dirs_v0(const char *opt_arg, struct xt_set_info_v0 *info)
149 {
150 	char *saved = strdup(opt_arg);
151 	char *ptr, *tmp = saved;
152 	int i = 0;
153 
154 	while (i < (IPSET_DIM_MAX - 1) && tmp != NULL) {
155 		ptr = strsep(&tmp, ",");
156 		if (strncmp(ptr, "src", 3) == 0)
157 			info->u.flags[i++] |= IPSET_SRC;
158 		else if (strncmp(ptr, "dst", 3) == 0)
159 			info->u.flags[i++] |= IPSET_DST;
160 		else
161 			xtables_error(PARAMETER_PROBLEM,
162 				"You must spefify (the comma separated list of) 'src' or 'dst'.");
163 	}
164 
165 	if (tmp)
166 		xtables_error(PARAMETER_PROBLEM,
167 			      "Can't be more src/dst options than %i.",
168 			      IPSET_DIM_MAX);
169 
170 	free(saved);
171 }
172 
173 static void
parse_dirs(const char * opt_arg,struct xt_set_info * info)174 parse_dirs(const char *opt_arg, struct xt_set_info *info)
175 {
176 	char *saved = strdup(opt_arg);
177 	char *ptr, *tmp = saved;
178 
179 	while (info->dim < IPSET_DIM_MAX && tmp != NULL) {
180 		info->dim++;
181 		ptr = strsep(&tmp, ",");
182 		if (strncmp(ptr, "src", 3) == 0)
183 			info->flags |= (1 << info->dim);
184 		else if (strncmp(ptr, "dst", 3) != 0)
185 			xtables_error(PARAMETER_PROBLEM,
186 				"You must spefify (the comma separated list of) 'src' or 'dst'.");
187 	}
188 
189 	if (tmp)
190 		xtables_error(PARAMETER_PROBLEM,
191 			      "Can't be more src/dst options than %i.",
192 			      IPSET_DIM_MAX);
193 
194 	free(saved);
195 }
196 
197 #endif /*_LIBXT_SET_H*/
198