1 #include <sys/time.h>
2 #include <sys/socket.h>
3 
4 #include <arpa/inet.h>
5 #include <err.h>
6 #include <errno.h>
7 #include <inttypes.h>
8 #include <stdio.h>
9 #include <stdlib.h>
10 #include <string.h>
11 
12 #include "smtp_proc.h"
13 
14 #define NITEMS(x) (sizeof(x) / sizeof(*x))
15 
16 typedef int (*smtp_cb)(char *, int, time_t, char *, char *, uint64_t, uint64_t,
17     void *);
18 
19 struct smtp_callback;
20 
21 static int smtp_register(char *, char *, char *, smtp_cb);
22 static void smtp_connect(struct smtp_callback *, int, time_t, uint64_t,
23     uint64_t, char *);
24 static void smtp_data(struct smtp_callback *, int, time_t, uint64_t, uint64_t,
25     char *);
26 static void smtp_data_line(struct smtp_callback *, int, time_t, uint64_t,
27     uint64_t, char *);
28 static void smtp_rset(struct smtp_callback *, int, time_t, uint64_t, uint64_t,
29     char *);
30 static void smtp_quit(struct smtp_callback *, int, time_t, uint64_t, uint64_t,
31     char *);
32 static void smtp_noop(struct smtp_callback *, int, time_t, uint64_t, uint64_t,
33     char *);
34 static void smtp_help(struct smtp_callback *, int, time_t, uint64_t, uint64_t,
35     char *);
36 static void smtp_wiz(struct smtp_callback *, int, time_t, uint64_t, uint64_t,
37     char *);
38 static void smtp_commit(struct smtp_callback *, int, time_t, uint64_t, uint64_t,
39     char *);
40 static void smtp_handle(struct smtp_callback *, int, time_t, uint64_t, uint64_t,
41     void *);
42 
43 struct smtp_callback {
44 	char *type;
45 	char *phase;
46 	char *direction;
47 	void (*smtp_parse)(struct smtp_callback *, int, time_t, uint64_t,
48 	    uint64_t, char *);
49 	smtp_cb cb;
50 } smtp_callbacks[] = {
51 	{"filter", "connect", "smtp-in", smtp_connect, NULL},
52 	{"filter", "data", "smtp-in", smtp_data, NULL},
53 	{"filter", "data-line", "smtp-in", smtp_data_line, NULL},
54 	{"filter", "rset", "smtp-in", smtp_rset, NULL},
55 	{"filter", "quit", "smtp-in", smtp_quit, NULL},
56 	{"filter", "noop", "smtp-in", smtp_noop, NULL},
57 	{"filter", "help", "smtp-in", smtp_help, NULL},
58 	{"filter", "wiz", "smtp-in", smtp_wiz, NULL},
59 	{"filter", "commit", "smtp-in", smtp_commit, NULL}
60 };
61 
62 static int ready = 0;
63 
64 int
65 smtp_register_filter_connect(enum filter_decision (*cb)(char *, int, time_t,
66     char *, char *, uint64_t, uint64_t, struct smtp_filter_connect *))
67 {
68 	return smtp_register("filter", "connect", "smtp-in", (smtp_cb) cb);
69 }
70 
71 void
72 smtp_run(void)
73 {
74 	char *line = NULL;
75 	size_t linesize = 0;
76 	ssize_t linelen;
77 	char *start, *end, *type, *direction, *phase, *params;
78 	int version;
79 	time_t tm;
80 	uint64_t reqid, token;
81 	int i;
82 
83 	printf("register|ready\n");
84 	ready = 1;
85 
86 	while ((linelen = getline(&line, &linesize, stdin)) != -1) {
87 		if (line[linelen - 1] != '\n')
88 			errx(1, "Invalid line received: missing newline");
89 		line[linelen - 1] = '\0';
90 		type = line;
91 		if ((start = strchr(type, '|')) == NULL)
92 			errx(1, "Invalid line received: missing version");
93 		start++[0] = '\0';
94 		if ((end = strchr(start, '|')) == NULL)
95 			errx(1, "Invalid line received: missing time");
96 		end++[0] = '\0';
97 		if (strcmp(start, "1") != 0)
98 			errx(1, "Unsupported protocol received: %s", start);
99 		version = 1;
100 		start = end;
101 		if ((direction = strchr(start, '|')) == NULL)
102 			errx(1, "Invalid line received: missing direction");
103 		direction++[0] = '\0';
104 		tm = (time_t) strtoull(start, &end, 10);
105 		if (start[0] == '\0' || end[0] != '\0')
106 			errx(1, "Invalid line received: invalid timestamp");
107 		if ((phase = strchr(direction, '|')) == NULL)
108 			errx(1, "Invalid line receieved: missing phase");
109 		phase++[0] = '\0';
110 		if ((start = strchr(phase, '|')) == NULL)
111 			errx(1, "Invalid line received: missing reqid");
112 		start++[0] = '\0';
113 		reqid = strtoull(start, &end, 16);
114 		if (start[0] == '|' || end[0] != '|')
115 			errx(1, "Invalid line received: invalid reqid");
116 		end++[0] = '\0';
117 		start = end;
118 		token = strtoull(start, &end, 16);
119 		if (start[0] == '|' || end[0] != '|')
120 			errx(1, "Invalid line received: invalid token");
121 		params = end + 1;
122 
123 		for (i = 0; i < NITEMS(smtp_callbacks); i++) {
124 			if (strcmp(type, smtp_callbacks[i].type) == 0 &&
125 			    strcmp(phase, smtp_callbacks[i].phase) == 0 &&
126 			    strcmp(direction, smtp_callbacks[i].direction) == 0)
127 				break;
128 		}
129 		if (i == NITEMS(smtp_callbacks)) {
130 			errx(1, "Invalid line received: received unregistered "
131 			    "%s: %s", type, phase);
132 		}
133 		smtp_callbacks[i].smtp_parse(&(smtp_callbacks[i]), version, tm,
134 		    reqid, token, params);
135 	}
136 }
137 
138 static void
139 smtp_connect(struct smtp_callback *cb, int version, time_t tm, uint64_t reqid,
140     uint64_t token, char *params)
141 {
142 	struct smtp_filter_connect sfconnect;
143 	char *address;
144 	int ret;
145 
146 	sfconnect.hostname = params;
147 	if ((address = strchr(params, '|')) == NULL)
148 		errx(1, "Invalid line received: missing address");
149 	address++[0] = '\0';
150 
151 	sfconnect.af = AF_INET;
152 	if (strncasecmp(address, "ipv6:", 5) == 0) {
153 		sfconnect.af = AF_INET6;
154 		address += 5;
155 	}
156 
157 	ret = inet_pton(sfconnect.af, address, sfconnect.af == AF_INET ?
158 	    (void *)&(sfconnect.addr) : (void *)&(sfconnect.addr6));
159 	if (ret == 0)
160 		errx(1, "Invalid line received: Couldn't parse address");
161 	if (ret == -1)
162 		err(1, "Couldn't convert address");
163 
164 	smtp_handle(cb, version, tm, reqid, token, (void *)(&sfconnect));
165 }
166 
167 static void 
168 smtp_data(struct smtp_callback *cb, int version, time_t tm, uint64_t reqid,
169     uint64_t token, char *params)
170 {
171 }
172 
173 static void 
174 smtp_data_line(struct smtp_callback *cb, int version, time_t tm, uint64_t reqid,
175     uint64_t token, char *params)
176 {
177 }
178 
179 static void 
180 smtp_rset(struct smtp_callback *cb, int version, time_t tm, uint64_t reqid,
181     uint64_t token, char *params)
182 {
183 }
184 
185 static void 
186 smtp_quit(struct smtp_callback *cb, int version, time_t tm, uint64_t reqid,
187     uint64_t token, char *params)
188 {
189 }
190 
191 static void 
192 smtp_noop(struct smtp_callback *cb, int version, time_t tm, uint64_t reqid,
193     uint64_t token, char *params)
194 {
195 }
196 
197 static void 
198 smtp_help(struct smtp_callback *cb, int version, time_t tm, uint64_t reqid,
199     uint64_t token, char *params)
200 {
201 }
202 
203 static void 
204 smtp_wiz(struct smtp_callback *cb, int version, time_t tm, uint64_t reqid,
205     uint64_t token, char *params)
206 {
207 }
208 
209 static void 
210 smtp_commit(struct smtp_callback *cb, int version, time_t tm, uint64_t reqid,
211     uint64_t token, char *params)
212 {
213 }
214 
215 static void
216 smtp_handle(struct smtp_callback *cb, int version, time_t tm, uint64_t reqid,
217     uint64_t token, void *params)
218 {
219 	int ret;
220 
221 	switch (cb->cb(cb->type, version, tm, cb->direction, cb->phase, reqid,
222 	    token, params)) {
223 	case FILTER_PROCEED:
224 		printf("filter-result|%016"PRIx64"|%016"PRIx64"|proceed\n",
225 		    token, reqid);
226 		break;
227 	case FILTER_REJECT:
228 		printf("filter-result|%016"PRIx64"|%016"PRIx64"|reject|%s\n",
229 		    token, reqid, "451 Proper message later");
230 		break;
231 	case FILTER_DISCONNECT:
232 		printf("filter-result|%016"PRIx64"|%016"PRIx64"|disconnect|"
233 		    "%s\n", token, reqid, "421 Proper message later");
234 		break;
235 	case FILTER_REWRITE:
236 		errx(1, "Not sure what is intended here yet");
237 	}
238 }
239 
240 static int
241 smtp_register(char *type, char *phase, char *direction, smtp_cb cb)
242 {
243 	int i;
244 
245 	if (ready) {
246 		errx(1, "Can't register when proc is running");
247 	}
248 	for (i = 0; i < NITEMS(smtp_callbacks); i++) {
249 		if (strcmp(type, smtp_callbacks[i].type) == 0 &&
250 		    strcmp(phase, smtp_callbacks[i].phase) == 0 &&
251 		    strcmp(direction, smtp_callbacks[i].direction) == 0) {
252 			if (smtp_callbacks[i].cb != NULL) {
253 				errno = EALREADY;
254 				return -1;
255 			}
256 			smtp_callbacks[i].cb = cb;
257 			printf("register|%s|%s|%s\n", type, direction, phase);
258 			return 0;
259 		}
260 	}
261 	errno = EINVAL;
262 	return -1;
263 }
264 
265 
266 //filter|1|1553668146|smtp-in|connect|478cc771bf86f378|5161a9ce4540b4d1|<unknown>|100.64.7.2