1 /*
2 * Common backend network APIs for CUPS.
3 *
4 * Copyright © 2020-2024 by OpenPrinting.
5 * Copyright © 2007-2016 by Apple Inc.
6 * Copyright © 2006-2007 by Easy Software Products, all rights reserved.
7 *
8 * Licensed under Apache License v2.0. See the file "LICENSE" for more
9 * information.
10 */
11
12 /*
13 * Include necessary headers.
14 */
15
16 #include "backend-private.h"
17 #include <limits.h>
18 #include <sys/select.h>
19
20
21 /*
22 * 'backendCheckSideChannel()' - Check the side-channel for pending requests.
23 */
24
25 void
backendCheckSideChannel(int snmp_fd,http_addr_t * addr)26 backendCheckSideChannel(
27 int snmp_fd, /* I - SNMP socket */
28 http_addr_t *addr) /* I - Address of device */
29 {
30 fd_set input; /* Select input set */
31 struct timeval timeout; /* Select timeout */
32
33
34 FD_ZERO(&input);
35 FD_SET(CUPS_SC_FD, &input);
36
37 timeout.tv_sec = timeout.tv_usec = 0;
38
39 if (select(CUPS_SC_FD + 1, &input, NULL, NULL, &timeout) > 0)
40 backendNetworkSideCB(-1, -1, snmp_fd, addr, 0);
41 }
42
43
44 /*
45 * 'backendLookup()' - Lookup the given host and log addresses.
46 */
47
48 http_addrlist_t * /* O - List of addresses or NULL */
backendLookup(const char * hostname,int port,int * cancel)49 backendLookup(const char *hostname, /* I - Hostname */
50 int port, /* I - Port number */
51 int *cancel) /* I - Variable to watch for job cancel */
52 {
53 char portname[32], /* Port number as string */
54 addrname[256]; /* Address as string */
55 http_addrlist_t *addrlist, /* List of addresses */
56 *current; /* Current address */
57
58
59 /*
60 * Lookup the address for the named host...
61 */
62
63 snprintf(portname, sizeof(portname), "%d", port);
64
65 fputs("STATE: +connecting-to-device\n", stderr);
66 fprintf(stderr, "DEBUG: Looking up \"%s\"...\n", hostname);
67
68 while ((addrlist = httpAddrGetList(hostname, AF_UNSPEC, portname)) == NULL)
69 {
70 _cupsLangPrintFilter(stderr, "INFO", _("Unable to locate printer \"%s\"."), hostname);
71 sleep(10);
72
73 if (getenv("CLASS") != NULL)
74 {
75 fputs("STATE: -connecting-to-device\n", stderr);
76 exit(CUPS_BACKEND_STOP);
77 }
78
79 if (cancel && *cancel)
80 {
81 fputs("STATE: -connecting-to-device\n", stderr);
82 exit(CUPS_BACKEND_OK);
83 }
84 }
85
86 fputs("STATE: -connecting-to-device\n", stderr);
87
88 /*
89 * Log the addresses we got...
90 */
91
92 for (current = addrlist; current; current = current->next)
93 fprintf(stderr, "DEBUG: %s=%s\n", hostname, httpAddrString(¤t->addr, addrname, sizeof(addrname)));
94
95 /*
96 * Return...
97 */
98
99 return (addrlist);
100 }
101
102
103 /*
104 * 'backendNetworkSideCB()' - Handle common network side-channel commands.
105 */
106
107 int /* O - -1 on error, 0 on success */
backendNetworkSideCB(int print_fd,int device_fd,int snmp_fd,http_addr_t * addr,int use_bc)108 backendNetworkSideCB(
109 int print_fd, /* I - Print file or -1 */
110 int device_fd, /* I - Device file or -1 */
111 int snmp_fd, /* I - SNMP socket */
112 http_addr_t *addr, /* I - Address of device */
113 int use_bc) /* I - Use back-channel data? */
114 {
115 cups_sc_command_t command; /* Request command */
116 cups_sc_status_t status; /* Request/response status */
117 char data[65536]; /* Request/response data */
118 int datalen; /* Request/response data size */
119 const char *device_id; /* 1284DEVICEID env var */
120
121
122 datalen = sizeof(data);
123
124 if (cupsSideChannelRead(&command, &status, data, &datalen, 1.0))
125 return (-1);
126
127 switch (command)
128 {
129 case CUPS_SC_CMD_DRAIN_OUTPUT :
130 /*
131 * Our sockets disable the Nagle algorithm and data is sent immediately.
132 */
133
134 if (device_fd < 0)
135 status = CUPS_SC_STATUS_NOT_IMPLEMENTED;
136 else if (backendDrainOutput(print_fd, device_fd))
137 status = CUPS_SC_STATUS_IO_ERROR;
138 else
139 status = CUPS_SC_STATUS_OK;
140
141 datalen = 0;
142 break;
143
144 case CUPS_SC_CMD_GET_BIDI :
145 status = CUPS_SC_STATUS_OK;
146 data[0] = (char)use_bc;
147 datalen = 1;
148 break;
149
150 case CUPS_SC_CMD_SNMP_GET :
151 case CUPS_SC_CMD_SNMP_GET_NEXT :
152 fprintf(stderr, "DEBUG: CUPS_SC_CMD_SNMP_%s: %d (%s)\n",
153 command == CUPS_SC_CMD_SNMP_GET ? "GET" : "GET_NEXT", datalen,
154 data);
155
156 if (datalen < 2)
157 {
158 status = CUPS_SC_STATUS_BAD_MESSAGE;
159 datalen = 0;
160 break;
161 }
162
163 if (snmp_fd >= 0)
164 {
165 char *dataptr; /* Pointer into data */
166 cups_snmp_t packet; /* Packet from printer */
167 const char *snmp_value; /* CUPS_SNMP_VALUE env var */
168
169 if ((snmp_value = getenv("CUPS_SNMP_VALUE")) != NULL)
170 {
171 const char *snmp_count; /* CUPS_SNMP_COUNT env var */
172 int count; /* Repetition count */
173
174 if ((snmp_count = getenv("CUPS_SNMP_COUNT")) != NULL)
175 {
176 if ((count = atoi(snmp_count)) <= 0)
177 count = 1;
178 }
179 else
180 count = 1;
181
182 for (dataptr = data + strlen(data) + 1;
183 count > 0 && dataptr < (data + sizeof(data) - 1);
184 count --, dataptr += strlen(dataptr))
185 strlcpy(dataptr, snmp_value, sizeof(data) - (size_t)(dataptr - data));
186
187 fprintf(stderr, "DEBUG: Returning %s %s\n", data,
188 data + strlen(data) + 1);
189
190 status = CUPS_SC_STATUS_OK;
191 datalen = (int)(dataptr - data);
192 break;
193 }
194
195 if (!_cupsSNMPStringToOID(data, packet.object_name, CUPS_SNMP_MAX_OID))
196 {
197 status = CUPS_SC_STATUS_BAD_MESSAGE;
198 datalen = 0;
199 break;
200 }
201
202 status = CUPS_SC_STATUS_IO_ERROR;
203 datalen = 0;
204
205 if (_cupsSNMPWrite(snmp_fd, addr, CUPS_SNMP_VERSION_1,
206 _cupsSNMPDefaultCommunity(),
207 command == CUPS_SC_CMD_SNMP_GET ?
208 CUPS_ASN1_GET_REQUEST :
209 CUPS_ASN1_GET_NEXT_REQUEST, 1,
210 packet.object_name))
211 {
212 if (_cupsSNMPRead(snmp_fd, &packet, 1.0))
213 {
214 size_t i; /* Looping var */
215
216
217 if (!_cupsSNMPOIDToString(packet.object_name, data, sizeof(data)))
218 {
219 fputs("DEBUG: Bad OID returned!\n", stderr);
220 break;
221 }
222
223 datalen = (int)strlen(data) + 1;
224 dataptr = data + datalen;
225
226 switch (packet.object_type)
227 {
228 case CUPS_ASN1_BOOLEAN :
229 snprintf(dataptr, sizeof(data) - (size_t)(dataptr - data), "%d", packet.object_value.boolean);
230 datalen += (int)strlen(dataptr);
231 break;
232
233 case CUPS_ASN1_INTEGER :
234 snprintf(dataptr, sizeof(data) - (size_t)(dataptr - data), "%d",
235 packet.object_value.integer);
236 datalen += (int)strlen(dataptr);
237 break;
238
239 case CUPS_ASN1_BIT_STRING :
240 case CUPS_ASN1_OCTET_STRING :
241 if (packet.object_value.string.num_bytes < (sizeof(data) - (size_t)(dataptr - data)))
242 i = packet.object_value.string.num_bytes;
243 else
244 i = sizeof(data) - (size_t)(dataptr - data);
245
246 memcpy(dataptr, packet.object_value.string.bytes, i);
247
248 datalen += (int)i;
249 break;
250
251 case CUPS_ASN1_OID :
252 _cupsSNMPOIDToString(packet.object_value.oid, dataptr,
253 sizeof(data) - (size_t)(dataptr - data));
254 datalen += (int)strlen(dataptr);
255 break;
256
257 case CUPS_ASN1_HEX_STRING :
258 for (i = 0;
259 i < packet.object_value.string.num_bytes &&
260 dataptr < (data + sizeof(data) - 3);
261 i ++, dataptr += 2)
262 snprintf(dataptr, sizeof(data) - (size_t)(dataptr - data), "%02X", packet.object_value.string.bytes[i]);
263 datalen += (int)strlen(dataptr);
264 break;
265
266 case CUPS_ASN1_COUNTER :
267 snprintf(dataptr, sizeof(data) - (size_t)(dataptr - data), "%u", packet.object_value.counter);
268 datalen += (int)strlen(dataptr);
269 break;
270
271 case CUPS_ASN1_GAUGE :
272 snprintf(dataptr, sizeof(data) - (size_t)(dataptr - data), "%u", packet.object_value.gauge);
273 datalen += (int)strlen(dataptr);
274 break;
275
276 case CUPS_ASN1_TIMETICKS :
277 snprintf(dataptr, sizeof(data) - (size_t)(dataptr - data), "%u", packet.object_value.timeticks);
278 datalen += (int)strlen(dataptr);
279 break;
280
281 default :
282 fprintf(stderr, "DEBUG: Unknown OID value type %02X.\n", packet.object_type);
283
284 case CUPS_ASN1_NULL_VALUE :
285 dataptr[0] = '\0';
286 break;
287 }
288
289 fprintf(stderr, "DEBUG: Returning %s %s\n", data, data + datalen);
290
291 status = CUPS_SC_STATUS_OK;
292 }
293 else
294 fputs("DEBUG: SNMP read error...\n", stderr);
295 }
296 else
297 fputs("DEBUG: SNMP write error...\n", stderr);
298 break;
299 }
300
301 status = CUPS_SC_STATUS_NOT_IMPLEMENTED;
302 datalen = 0;
303 break;
304
305 case CUPS_SC_CMD_GET_CONNECTED :
306 status = CUPS_SC_STATUS_OK;
307 data[0] = device_fd != -1;
308 datalen = 1;
309 break;
310
311 case CUPS_SC_CMD_GET_DEVICE_ID :
312 if (snmp_fd >= 0)
313 {
314 cups_snmp_t packet; /* Packet from printer */
315 static const int ppmPrinterIEEE1284DeviceId[] =
316 { CUPS_OID_ppmPrinterIEEE1284DeviceId,1,-1 };
317
318
319 status = CUPS_SC_STATUS_IO_ERROR;
320 datalen = 0;
321
322 if (_cupsSNMPWrite(snmp_fd, addr, CUPS_SNMP_VERSION_1,
323 _cupsSNMPDefaultCommunity(),
324 CUPS_ASN1_GET_REQUEST, 1,
325 ppmPrinterIEEE1284DeviceId))
326 {
327 if (_cupsSNMPRead(snmp_fd, &packet, 1.0) &&
328 packet.object_type == CUPS_ASN1_OCTET_STRING)
329 {
330 strlcpy(data, (char *)packet.object_value.string.bytes,
331 sizeof(data));
332 datalen = (int)strlen(data);
333 status = CUPS_SC_STATUS_OK;
334 }
335 }
336
337 break;
338 }
339
340 if ((device_id = getenv("1284DEVICEID")) != NULL)
341 {
342 strlcpy(data, device_id, sizeof(data));
343 datalen = (int)strlen(data);
344 status = CUPS_SC_STATUS_OK;
345 break;
346 }
347
348 default :
349 status = CUPS_SC_STATUS_NOT_IMPLEMENTED;
350 datalen = 0;
351 break;
352 }
353
354 return (cupsSideChannelWrite(command, status, data, datalen, 1.0));
355 }
356