1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /*
23 * PPPoE common utilities and data.
24 *
25 * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
26 * Use is subject to license terms.
27 */
28
29 #pragma ident "%Z%%M% %I% %E% SMI"
30
31 #include <stdio.h>
32 #include <unistd.h>
33 #include <string.h>
34 #include <errno.h>
35 #include <netdb.h>
36 #include <assert.h>
37 #include <stropts.h>
38 #include <sys/types.h>
39 #include <inet/common.h>
40 #include <netinet/in.h>
41 #include <net/sppptun.h>
42 #include <net/pppoe.h>
43 #include <arpa/inet.h>
44
45 #include "common.h"
46
47 /* Not all functions are used by all applications. Let lint know this. */
48 /*LINTLIBRARY*/
49
50 /* Common I/O buffers */
51 uint32_t pkt_input[PKT_INPUT_LEN / sizeof (uint32_t)];
52 uint32_t pkt_octl[PKT_OCTL_LEN / sizeof (uint32_t)];
53 uint32_t pkt_output[PKT_OUTPUT_LEN / sizeof (uint32_t)];
54
55 const char tunnam[] = "/dev/" PPP_TUN_NAME;
56
57 const ether_addr_t ether_bcast = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
58
59 /*
60 * Wrapper for standard strerror() function -- the standard allows
61 * that routine to return NULL, and that's inconvenient to handle.
62 * This function never returns NULL.
63 */
64 const char *
mystrerror(int err)65 mystrerror(int err)
66 {
67 const char *estr;
68 static char ebuf[64];
69
70 if ((estr = strerror(err)) != NULL)
71 return (estr);
72 (void) snprintf(ebuf, sizeof (ebuf), "Error:%d", err);
73 return (ebuf);
74 }
75
76 /*
77 * Wrapper for standard perror() function -- the standard definition
78 * of perror doesn't include the program name in the output and is
79 * thus inconvenient to use.
80 */
81 void
myperror(const char * emsg)82 myperror(const char *emsg)
83 {
84 (void) fprintf(stderr, "%s: %s: %s\n", myname, emsg,
85 mystrerror(errno));
86 }
87
88 /*
89 * Wrapper for standard getmsg() function. Completely discards any
90 * fragmented messages because we don't expect ever to see these from
91 * a properly functioning tunnel driver. Returns flags
92 * (MORECTL|MOREDATA) as seen by interface.
93 */
94 int
mygetmsg(int fd,struct strbuf * ctrl,struct strbuf * data,int * flags)95 mygetmsg(int fd, struct strbuf *ctrl, struct strbuf *data, int *flags)
96 {
97 int retv;
98 int hadflags;
99
100 hadflags = getmsg(fd, ctrl, data, flags);
101 if (hadflags <= 0 || !(hadflags & (MORECTL | MOREDATA)))
102 return (hadflags);
103
104 do {
105 if (flags != NULL)
106 *flags = 0;
107 retv = getmsg(fd, ctrl, data, flags);
108 } while (retv > 0 || (retv < 0 && errno == EINTR));
109
110 /*
111 * What remains at this point is the tail end of the
112 * truncated message. Toss it.
113 */
114
115 return (retv < 0 ? retv : hadflags);
116 }
117
118 /*
119 * Common wrapper function for STREAMS I_STR ioctl. Returns -1 on
120 * failure, 0 for success.
121 */
122 int
strioctl(int fd,int cmd,void * ptr,int ilen,int olen)123 strioctl(int fd, int cmd, void *ptr, int ilen, int olen)
124 {
125 struct strioctl str;
126
127 str.ic_cmd = cmd;
128 str.ic_timout = 0; /* Default timeout; 15 seconds */
129 str.ic_len = ilen;
130 str.ic_dp = ptr;
131
132 if (ioctl(fd, I_STR, &str) == -1) {
133 return (-1);
134 }
135 if (str.ic_len != olen) {
136 errno = EINVAL;
137 return (-1);
138 }
139 return (0);
140 }
141
142 /*
143 * Format a PPPoE header in the user's buffer. The returned pointer
144 * is either identical to the first argument, or is NULL if it's not
145 * usable. On entry, dptr should point to the first byte after the
146 * Ethertype field, codeval should be one of the POECODE_* values, and
147 * sessionid should be the assigned session ID number or one of the
148 * special POESESS_* values.
149 */
150 poep_t *
poe_mkheader(void * dptr,uint8_t codeval,int sessionid)151 poe_mkheader(void *dptr, uint8_t codeval, int sessionid)
152 {
153 poep_t *poep;
154
155 /* Discard obvious junk. */
156 assert(dptr != NULL && IS_P2ALIGNED(dptr, sizeof (poep_t *)));
157
158 /* Initialize the header */
159 poep = (poep_t *)dptr;
160 poep->poep_version_type = POE_VERSION;
161 poep->poep_code = codeval;
162 poep->poep_session_id = htons(sessionid);
163 poep->poep_length = htons(0);
164 return (poep);
165 }
166
167 /*
168 * Validate that a given tag is intact. This is intended to be used
169 * in tag-parsing loops before attempting to access the tag data.
170 */
171 boolean_t
poe_tagcheck(const poep_t * poep,int length,const uint8_t * tptr)172 poe_tagcheck(const poep_t *poep, int length, const uint8_t *tptr)
173 {
174 int plen;
175 const uint8_t *tstart, *tend;
176
177 if (poep == NULL || !IS_P2ALIGNED(poep, sizeof (uint16_t)) ||
178 tptr == NULL || length < sizeof (*poep))
179 return (B_FALSE);
180
181 plen = poe_length(poep);
182 if (plen + sizeof (*poep) > length)
183 return (B_FALSE);
184
185 tstart = (const uint8_t *)(poep+1);
186 tend = tstart + plen;
187
188 /*
189 * Note careful dereference of tptr; it might be near the end
190 * already, so we have to range check it before dereferencing
191 * to get the actual tag length. Yes, it looks like we have
192 * duplicate array end checks. No, they're not duplicates.
193 */
194 if (tptr < tstart || tptr+POET_HDRLEN > tend ||
195 tptr+POET_HDRLEN+POET_GET_LENG(tptr) > tend)
196 return (B_FALSE);
197 return (B_TRUE);
198 }
199
200 static int
poe_tag_insert(poep_t * poep,uint16_t ttype,const void * data,size_t dlen)201 poe_tag_insert(poep_t *poep, uint16_t ttype, const void *data, size_t dlen)
202 {
203 int plen;
204 uint8_t *dp;
205
206 plen = poe_length(poep);
207 if (data == NULL)
208 dlen = 0;
209 if (sizeof (*poep) + plen + POET_HDRLEN + dlen > PPPOE_MSGMAX)
210 return (-1);
211 dp = (uint8_t *)(poep + 1) + plen;
212 POET_SET_TYPE(dp, ttype);
213 POET_SET_LENG(dp, dlen);
214 if (dlen > 0)
215 (void) memcpy(POET_DATA(dp), data, dlen);
216 poep->poep_length = htons(plen + POET_HDRLEN + dlen);
217 return (0);
218 }
219
220 /*
221 * Add a tag with text string data to a PPPoE packet being
222 * constructed. Returns -1 if it doesn't fit, or 0 for success.
223 */
224 int
poe_add_str(poep_t * poep,uint16_t ttype,const char * str)225 poe_add_str(poep_t *poep, uint16_t ttype, const char *str)
226 {
227 return (poe_tag_insert(poep, ttype, str, strlen(str)));
228 }
229
230 /*
231 * Add a tag with 32-bit integer data to a PPPoE packet being
232 * constructed. Returns -1 if it doesn't fit, or 0 for success.
233 */
234 int
poe_add_long(poep_t * poep,uint16_t ttype,uint32_t val)235 poe_add_long(poep_t *poep, uint16_t ttype, uint32_t val)
236 {
237 val = htonl(val);
238 return (poe_tag_insert(poep, ttype, &val, sizeof (val)));
239 }
240
241 /*
242 * Add a tag with two 32-bit integers to a PPPoE packet being
243 * constructed. Returns -1 if it doesn't fit, or 0 for success.
244 */
245 int
poe_two_longs(poep_t * poep,uint16_t ttype,uint32_t val1,uint32_t val2)246 poe_two_longs(poep_t *poep, uint16_t ttype, uint32_t val1, uint32_t val2)
247 {
248 uint32_t vals[2];
249
250 vals[0] = htonl(val1);
251 vals[1] = htonl(val2);
252 return (poe_tag_insert(poep, ttype, vals, sizeof (vals)));
253 }
254
255 /*
256 * Copy a single tag and its data from one PPPoE packet to a PPPoE
257 * packet being constructed. Returns -1 if it doesn't fit, or 0 for
258 * success.
259 */
260 int
poe_tag_copy(poep_t * poep,const uint8_t * tagp)261 poe_tag_copy(poep_t *poep, const uint8_t *tagp)
262 {
263 int tlen;
264 int plen;
265
266 tlen = POET_GET_LENG(tagp) + POET_HDRLEN;
267 plen = poe_length(poep);
268 if (sizeof (*poep) + plen + tlen > PPPOE_MSGMAX)
269 return (-1);
270 (void) memcpy((uint8_t *)(poep + 1) + plen, tagp, tlen);
271 poep->poep_length = htons(tlen + plen);
272 return (0);
273 }
274
275 struct tag_list {
276 int tl_type;
277 const char *tl_name;
278 };
279
280 /* List of PPPoE data tag types. */
281 static const struct tag_list tag_list[] = {
282 { POETT_END, "End-Of-List" },
283 { POETT_SERVICE, "Service-Name" },
284 { POETT_ACCESS, "AC-Name" },
285 { POETT_UNIQ, "Host-Uniq" },
286 { POETT_COOKIE, "AC-Cookie" },
287 { POETT_VENDOR, "Vendor-Specific" },
288 { POETT_RELAY, "Relay-Session-Id" },
289 { POETT_NAMERR, "Service-Name-Error" },
290 { POETT_SYSERR, "AC-System-Error" },
291 { POETT_GENERR, "Generic-Error" },
292 { POETT_MULTI, "Multicast-Capable" },
293 { POETT_HURL, "Host-URL" },
294 { POETT_MOTM, "Message-Of-The-Minute" },
295 { POETT_RTEADD, "IP-Route-Add" },
296 { 0, NULL }
297 };
298
299 /* List of PPPoE message code numbers. */
300 static const struct tag_list code_list[] = {
301 { POECODE_DATA, "Data" },
302 { POECODE_PADO, "Active Discovery Offer" },
303 { POECODE_PADI, "Active Discovery Initiation" },
304 { POECODE_PADR, "Active Discovery Request" },
305 { POECODE_PADS, "Active Discovery Session-confirmation" },
306 { POECODE_PADT, "Active Discovery Terminate" },
307 { POECODE_PADM, "Active Discovery Message" },
308 { POECODE_PADN, "Active Discovery Network" },
309 { 0, NULL }
310 };
311
312 /*
313 * Given a tag type number, return a pointer to a string describing
314 * the tag.
315 */
316 const char *
poe_tagname(uint16_t tagtype)317 poe_tagname(uint16_t tagtype)
318 {
319 const struct tag_list *tlp;
320 static char tname[32];
321
322 for (tlp = tag_list; tlp->tl_name != NULL; tlp++)
323 if (tagtype == tlp->tl_type)
324 return (tlp->tl_name);
325 (void) sprintf(tname, "Tag%d", tagtype);
326 return (tname);
327 }
328
329 /*
330 * Given a PPPoE message code number, return a pointer to a string
331 * describing the message.
332 */
333 const char *
poe_codename(uint8_t codetype)334 poe_codename(uint8_t codetype)
335 {
336 const struct tag_list *tlp;
337 static char tname[32];
338
339 for (tlp = code_list; tlp->tl_name != NULL; tlp++)
340 if (codetype == tlp->tl_type)
341 return (tlp->tl_name);
342 (void) sprintf(tname, "Code%d", codetype);
343 return (tname);
344 }
345
346 /*
347 * Given a tunnel driver address structure, return a pointer to a
348 * string naming that Ethernet host.
349 */
350 const char *
ehost2(const struct ether_addr * ea)351 ehost2(const struct ether_addr *ea)
352 {
353 static char hbuf[MAXHOSTNAMELEN+1];
354
355 if (ea == NULL)
356 return ("NULL");
357 if (ether_ntohost(hbuf, ea) == 0)
358 return (hbuf);
359 return (ether_ntoa(ea));
360 }
361
362 const char *
ehost(const ppptun_atype * pap)363 ehost(const ppptun_atype *pap)
364 {
365 return (ehost2((const struct ether_addr *)pap));
366 }
367
368 /*
369 * Given an Internet address (in network byte order), return a pointer
370 * to a string naming the host.
371 */
372 const char *
ihost(uint32_t haddr)373 ihost(uint32_t haddr)
374 {
375 struct hostent *hp;
376 struct sockaddr_in sin;
377
378 (void) memset(&sin, '\0', sizeof (sin));
379 sin.sin_addr.s_addr = haddr;
380 hp = gethostbyaddr((const char *)&sin, sizeof (sin), AF_INET);
381 if (hp != NULL)
382 return (hp->h_name);
383 return (inet_ntoa(sin.sin_addr));
384 }
385
386 int
hexdecode(char chr)387 hexdecode(char chr)
388 {
389 if (chr >= '0' && chr <= '9')
390 return ((int)(chr - '0'));
391 if (chr >= 'a' && chr <= 'f')
392 return ((int)(chr - 'a' + 10));
393 return ((int)(chr - 'A' + 10));
394 }
395