1 #include "cache.h"
2 #include "repository.h"
3 #include "commit.h"
4 #include "walker.h"
5 #include "http.h"
6 #include "list.h"
7 #include "transport.h"
8 #include "packfile.h"
9 #include "object-store.h"
10
11 struct alt_base {
12 char *base;
13 int got_indices;
14 struct packed_git *packs;
15 struct alt_base *next;
16 };
17
18 enum object_request_state {
19 WAITING,
20 ABORTED,
21 ACTIVE,
22 COMPLETE
23 };
24
25 struct object_request {
26 struct walker *walker;
27 struct object_id oid;
28 struct alt_base *repo;
29 enum object_request_state state;
30 struct http_object_request *req;
31 struct list_head node;
32 };
33
34 struct alternates_request {
35 struct walker *walker;
36 const char *base;
37 struct strbuf *url;
38 struct strbuf *buffer;
39 struct active_request_slot *slot;
40 int http_specific;
41 };
42
43 struct walker_data {
44 const char *url;
45 int got_alternates;
46 struct alt_base *alt;
47 };
48
49 static LIST_HEAD(object_queue_head);
50
51 static void fetch_alternates(struct walker *walker, const char *base);
52
53 static void process_object_response(void *callback_data);
54
start_object_request(struct walker * walker,struct object_request * obj_req)55 static void start_object_request(struct walker *walker,
56 struct object_request *obj_req)
57 {
58 struct active_request_slot *slot;
59 struct http_object_request *req;
60
61 req = new_http_object_request(obj_req->repo->base, &obj_req->oid);
62 if (req == NULL) {
63 obj_req->state = ABORTED;
64 return;
65 }
66 obj_req->req = req;
67
68 slot = req->slot;
69 slot->callback_func = process_object_response;
70 slot->callback_data = obj_req;
71
72 /* Try to get the request started, abort the request on error */
73 obj_req->state = ACTIVE;
74 if (!start_active_slot(slot)) {
75 obj_req->state = ABORTED;
76 release_http_object_request(req);
77 return;
78 }
79 }
80
finish_object_request(struct object_request * obj_req)81 static void finish_object_request(struct object_request *obj_req)
82 {
83 if (finish_http_object_request(obj_req->req))
84 return;
85
86 if (obj_req->req->rename == 0)
87 walker_say(obj_req->walker, "got %s\n", oid_to_hex(&obj_req->oid));
88 }
89
process_object_response(void * callback_data)90 static void process_object_response(void *callback_data)
91 {
92 struct object_request *obj_req =
93 (struct object_request *)callback_data;
94 struct walker *walker = obj_req->walker;
95 struct walker_data *data = walker->data;
96 struct alt_base *alt = data->alt;
97
98 process_http_object_request(obj_req->req);
99 obj_req->state = COMPLETE;
100
101 normalize_curl_result(&obj_req->req->curl_result,
102 obj_req->req->http_code,
103 obj_req->req->errorstr,
104 sizeof(obj_req->req->errorstr));
105
106 /* Use alternates if necessary */
107 if (missing_target(obj_req->req)) {
108 fetch_alternates(walker, alt->base);
109 if (obj_req->repo->next != NULL) {
110 obj_req->repo =
111 obj_req->repo->next;
112 release_http_object_request(obj_req->req);
113 start_object_request(walker, obj_req);
114 return;
115 }
116 }
117
118 finish_object_request(obj_req);
119 }
120
release_object_request(struct object_request * obj_req)121 static void release_object_request(struct object_request *obj_req)
122 {
123 if (obj_req->req !=NULL && obj_req->req->localfile != -1)
124 error("fd leakage in release: %d", obj_req->req->localfile);
125
126 list_del(&obj_req->node);
127 free(obj_req);
128 }
129
fill_active_slot(struct walker * walker)130 static int fill_active_slot(struct walker *walker)
131 {
132 struct object_request *obj_req;
133 struct list_head *pos, *tmp, *head = &object_queue_head;
134
135 list_for_each_safe(pos, tmp, head) {
136 obj_req = list_entry(pos, struct object_request, node);
137 if (obj_req->state == WAITING) {
138 if (has_object_file(&obj_req->oid))
139 obj_req->state = COMPLETE;
140 else {
141 start_object_request(walker, obj_req);
142 return 1;
143 }
144 }
145 }
146 return 0;
147 }
148
prefetch(struct walker * walker,unsigned char * sha1)149 static void prefetch(struct walker *walker, unsigned char *sha1)
150 {
151 struct object_request *newreq;
152 struct walker_data *data = walker->data;
153
154 newreq = xmalloc(sizeof(*newreq));
155 newreq->walker = walker;
156 oidread(&newreq->oid, sha1);
157 newreq->repo = data->alt;
158 newreq->state = WAITING;
159 newreq->req = NULL;
160
161 http_is_verbose = walker->get_verbosely;
162 list_add_tail(&newreq->node, &object_queue_head);
163
164 fill_active_slots();
165 step_active_slots();
166 }
167
is_alternate_allowed(const char * url)168 static int is_alternate_allowed(const char *url)
169 {
170 const char *protocols[] = {
171 "http", "https", "ftp", "ftps"
172 };
173 int i;
174
175 if (http_follow_config != HTTP_FOLLOW_ALWAYS) {
176 warning("alternate disabled by http.followRedirects: %s", url);
177 return 0;
178 }
179
180 for (i = 0; i < ARRAY_SIZE(protocols); i++) {
181 const char *end;
182 if (skip_prefix(url, protocols[i], &end) &&
183 starts_with(end, "://"))
184 break;
185 }
186
187 if (i >= ARRAY_SIZE(protocols)) {
188 warning("ignoring alternate with unknown protocol: %s", url);
189 return 0;
190 }
191 if (!is_transport_allowed(protocols[i], 0)) {
192 warning("ignoring alternate with restricted protocol: %s", url);
193 return 0;
194 }
195
196 return 1;
197 }
198
process_alternates_response(void * callback_data)199 static void process_alternates_response(void *callback_data)
200 {
201 struct alternates_request *alt_req =
202 (struct alternates_request *)callback_data;
203 struct walker *walker = alt_req->walker;
204 struct walker_data *cdata = walker->data;
205 struct active_request_slot *slot = alt_req->slot;
206 struct alt_base *tail = cdata->alt;
207 const char *base = alt_req->base;
208 const char null_byte = '\0';
209 char *data;
210 int i = 0;
211
212 normalize_curl_result(&slot->curl_result, slot->http_code,
213 curl_errorstr, sizeof(curl_errorstr));
214
215 if (alt_req->http_specific) {
216 if (slot->curl_result != CURLE_OK ||
217 !alt_req->buffer->len) {
218
219 /* Try reusing the slot to get non-http alternates */
220 alt_req->http_specific = 0;
221 strbuf_reset(alt_req->url);
222 strbuf_addf(alt_req->url, "%s/objects/info/alternates",
223 base);
224 curl_easy_setopt(slot->curl, CURLOPT_URL,
225 alt_req->url->buf);
226 active_requests++;
227 slot->in_use = 1;
228 if (slot->finished != NULL)
229 (*slot->finished) = 0;
230 if (!start_active_slot(slot)) {
231 cdata->got_alternates = -1;
232 slot->in_use = 0;
233 if (slot->finished != NULL)
234 (*slot->finished) = 1;
235 }
236 return;
237 }
238 } else if (slot->curl_result != CURLE_OK) {
239 if (!missing_target(slot)) {
240 cdata->got_alternates = -1;
241 return;
242 }
243 }
244
245 fwrite_buffer((char *)&null_byte, 1, 1, alt_req->buffer);
246 alt_req->buffer->len--;
247 data = alt_req->buffer->buf;
248
249 while (i < alt_req->buffer->len) {
250 int posn = i;
251 while (posn < alt_req->buffer->len && data[posn] != '\n')
252 posn++;
253 if (data[posn] == '\n') {
254 int okay = 0;
255 int serverlen = 0;
256 struct alt_base *newalt;
257 if (data[i] == '/') {
258 /*
259 * This counts
260 * http://git.host/pub/scm/linux.git/
261 * -----------here^
262 * so memcpy(dst, base, serverlen) will
263 * copy up to "...git.host".
264 */
265 const char *colon_ss = strstr(base,"://");
266 if (colon_ss) {
267 serverlen = (strchr(colon_ss + 3, '/')
268 - base);
269 okay = 1;
270 }
271 } else if (!memcmp(data + i, "../", 3)) {
272 /*
273 * Relative URL; chop the corresponding
274 * number of subpath from base (and ../
275 * from data), and concatenate the result.
276 *
277 * The code first drops ../ from data, and
278 * then drops one ../ from data and one path
279 * from base. IOW, one extra ../ is dropped
280 * from data than path is dropped from base.
281 *
282 * This is not wrong. The alternate in
283 * http://git.host/pub/scm/linux.git/
284 * to borrow from
285 * http://git.host/pub/scm/linus.git/
286 * is ../../linus.git/objects/. You need
287 * two ../../ to borrow from your direct
288 * neighbour.
289 */
290 i += 3;
291 serverlen = strlen(base);
292 while (i + 2 < posn &&
293 !memcmp(data + i, "../", 3)) {
294 do {
295 serverlen--;
296 } while (serverlen &&
297 base[serverlen - 1] != '/');
298 i += 3;
299 }
300 /* If the server got removed, give up. */
301 okay = strchr(base, ':') - base + 3 <
302 serverlen;
303 } else if (alt_req->http_specific) {
304 char *colon = strchr(data + i, ':');
305 char *slash = strchr(data + i, '/');
306 if (colon && slash && colon < data + posn &&
307 slash < data + posn && colon < slash) {
308 okay = 1;
309 }
310 }
311 if (okay) {
312 struct strbuf target = STRBUF_INIT;
313 strbuf_add(&target, base, serverlen);
314 strbuf_add(&target, data + i, posn - i);
315 if (!strbuf_strip_suffix(&target, "objects")) {
316 warning("ignoring alternate that does"
317 " not end in 'objects': %s",
318 target.buf);
319 strbuf_release(&target);
320 } else if (is_alternate_allowed(target.buf)) {
321 warning("adding alternate object store: %s",
322 target.buf);
323 newalt = xmalloc(sizeof(*newalt));
324 newalt->next = NULL;
325 newalt->base = strbuf_detach(&target, NULL);
326 newalt->got_indices = 0;
327 newalt->packs = NULL;
328
329 while (tail->next != NULL)
330 tail = tail->next;
331 tail->next = newalt;
332 } else {
333 strbuf_release(&target);
334 }
335 }
336 }
337 i = posn + 1;
338 }
339
340 cdata->got_alternates = 1;
341 }
342
fetch_alternates(struct walker * walker,const char * base)343 static void fetch_alternates(struct walker *walker, const char *base)
344 {
345 struct strbuf buffer = STRBUF_INIT;
346 struct strbuf url = STRBUF_INIT;
347 struct active_request_slot *slot;
348 struct alternates_request alt_req;
349 struct walker_data *cdata = walker->data;
350
351 /*
352 * If another request has already started fetching alternates,
353 * wait for them to arrive and return to processing this request's
354 * curl message
355 */
356 while (cdata->got_alternates == 0) {
357 step_active_slots();
358 }
359
360 /* Nothing to do if they've already been fetched */
361 if (cdata->got_alternates == 1)
362 return;
363
364 /* Start the fetch */
365 cdata->got_alternates = 0;
366
367 if (walker->get_verbosely)
368 fprintf(stderr, "Getting alternates list for %s\n", base);
369
370 strbuf_addf(&url, "%s/objects/info/http-alternates", base);
371
372 /*
373 * Use a callback to process the result, since another request
374 * may fail and need to have alternates loaded before continuing
375 */
376 slot = get_active_slot();
377 slot->callback_func = process_alternates_response;
378 alt_req.walker = walker;
379 slot->callback_data = &alt_req;
380
381 curl_easy_setopt(slot->curl, CURLOPT_WRITEDATA, &buffer);
382 curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
383 curl_easy_setopt(slot->curl, CURLOPT_URL, url.buf);
384
385 alt_req.base = base;
386 alt_req.url = &url;
387 alt_req.buffer = &buffer;
388 alt_req.http_specific = 1;
389 alt_req.slot = slot;
390
391 if (start_active_slot(slot))
392 run_active_slot(slot);
393 else
394 cdata->got_alternates = -1;
395
396 strbuf_release(&buffer);
397 strbuf_release(&url);
398 }
399
fetch_indices(struct walker * walker,struct alt_base * repo)400 static int fetch_indices(struct walker *walker, struct alt_base *repo)
401 {
402 int ret;
403
404 if (repo->got_indices)
405 return 0;
406
407 if (walker->get_verbosely)
408 fprintf(stderr, "Getting pack list for %s\n", repo->base);
409
410 switch (http_get_info_packs(repo->base, &repo->packs)) {
411 case HTTP_OK:
412 case HTTP_MISSING_TARGET:
413 repo->got_indices = 1;
414 ret = 0;
415 break;
416 default:
417 repo->got_indices = 0;
418 ret = -1;
419 }
420
421 return ret;
422 }
423
http_fetch_pack(struct walker * walker,struct alt_base * repo,unsigned char * sha1)424 static int http_fetch_pack(struct walker *walker, struct alt_base *repo, unsigned char *sha1)
425 {
426 struct packed_git *target;
427 int ret;
428 struct slot_results results;
429 struct http_pack_request *preq;
430
431 if (fetch_indices(walker, repo))
432 return -1;
433 target = find_sha1_pack(sha1, repo->packs);
434 if (!target)
435 return -1;
436 close_pack_index(target);
437
438 if (walker->get_verbosely) {
439 fprintf(stderr, "Getting pack %s\n",
440 hash_to_hex(target->hash));
441 fprintf(stderr, " which contains %s\n",
442 hash_to_hex(sha1));
443 }
444
445 preq = new_http_pack_request(target->hash, repo->base);
446 if (preq == NULL)
447 goto abort;
448 preq->slot->results = &results;
449
450 if (start_active_slot(preq->slot)) {
451 run_active_slot(preq->slot);
452 if (results.curl_result != CURLE_OK) {
453 error("Unable to get pack file %s\n%s", preq->url,
454 curl_errorstr);
455 goto abort;
456 }
457 } else {
458 error("Unable to start request");
459 goto abort;
460 }
461
462 ret = finish_http_pack_request(preq);
463 release_http_pack_request(preq);
464 if (ret)
465 return ret;
466 http_install_packfile(target, &repo->packs);
467
468 return 0;
469
470 abort:
471 return -1;
472 }
473
abort_object_request(struct object_request * obj_req)474 static void abort_object_request(struct object_request *obj_req)
475 {
476 release_object_request(obj_req);
477 }
478
fetch_object(struct walker * walker,unsigned char * hash)479 static int fetch_object(struct walker *walker, unsigned char *hash)
480 {
481 char *hex = hash_to_hex(hash);
482 int ret = 0;
483 struct object_request *obj_req = NULL;
484 struct http_object_request *req;
485 struct list_head *pos, *head = &object_queue_head;
486
487 list_for_each(pos, head) {
488 obj_req = list_entry(pos, struct object_request, node);
489 if (hasheq(obj_req->oid.hash, hash))
490 break;
491 }
492 if (obj_req == NULL)
493 return error("Couldn't find request for %s in the queue", hex);
494
495 if (has_object_file(&obj_req->oid)) {
496 if (obj_req->req != NULL)
497 abort_http_object_request(obj_req->req);
498 abort_object_request(obj_req);
499 return 0;
500 }
501
502 while (obj_req->state == WAITING)
503 step_active_slots();
504
505 /*
506 * obj_req->req might change when fetching alternates in the callback
507 * process_object_response; therefore, the "shortcut" variable, req,
508 * is used only after we're done with slots.
509 */
510 while (obj_req->state == ACTIVE)
511 run_active_slot(obj_req->req->slot);
512
513 req = obj_req->req;
514
515 if (req->localfile != -1) {
516 close(req->localfile);
517 req->localfile = -1;
518 }
519
520 normalize_curl_result(&req->curl_result, req->http_code,
521 req->errorstr, sizeof(req->errorstr));
522
523 if (obj_req->state == ABORTED) {
524 ret = error("Request for %s aborted", hex);
525 } else if (req->curl_result != CURLE_OK &&
526 req->http_code != 416) {
527 if (missing_target(req))
528 ret = -1; /* Be silent, it is probably in a pack. */
529 else
530 ret = error("%s (curl_result = %d, http_code = %ld, sha1 = %s)",
531 req->errorstr, req->curl_result,
532 req->http_code, hex);
533 } else if (req->zret != Z_STREAM_END) {
534 walker->corrupt_object_found++;
535 ret = error("File %s (%s) corrupt", hex, req->url);
536 } else if (!oideq(&obj_req->oid, &req->real_oid)) {
537 ret = error("File %s has bad hash", hex);
538 } else if (req->rename < 0) {
539 struct strbuf buf = STRBUF_INIT;
540 loose_object_path(the_repository, &buf, &req->oid);
541 ret = error("unable to write sha1 filename %s", buf.buf);
542 strbuf_release(&buf);
543 }
544
545 release_http_object_request(req);
546 release_object_request(obj_req);
547 return ret;
548 }
549
fetch(struct walker * walker,unsigned char * hash)550 static int fetch(struct walker *walker, unsigned char *hash)
551 {
552 struct walker_data *data = walker->data;
553 struct alt_base *altbase = data->alt;
554
555 if (!fetch_object(walker, hash))
556 return 0;
557 while (altbase) {
558 if (!http_fetch_pack(walker, altbase, hash))
559 return 0;
560 fetch_alternates(walker, data->alt->base);
561 altbase = altbase->next;
562 }
563 return error("Unable to find %s under %s", hash_to_hex(hash),
564 data->alt->base);
565 }
566
fetch_ref(struct walker * walker,struct ref * ref)567 static int fetch_ref(struct walker *walker, struct ref *ref)
568 {
569 struct walker_data *data = walker->data;
570 return http_fetch_ref(data->alt->base, ref);
571 }
572
cleanup(struct walker * walker)573 static void cleanup(struct walker *walker)
574 {
575 struct walker_data *data = walker->data;
576 struct alt_base *alt, *alt_next;
577
578 if (data) {
579 alt = data->alt;
580 while (alt) {
581 alt_next = alt->next;
582
583 free(alt->base);
584 free(alt);
585
586 alt = alt_next;
587 }
588 free(data);
589 walker->data = NULL;
590 }
591 }
592
get_http_walker(const char * url)593 struct walker *get_http_walker(const char *url)
594 {
595 char *s;
596 struct walker_data *data = xmalloc(sizeof(struct walker_data));
597 struct walker *walker = xmalloc(sizeof(struct walker));
598
599 data->alt = xmalloc(sizeof(*data->alt));
600 data->alt->base = xstrdup(url);
601 for (s = data->alt->base + strlen(data->alt->base) - 1; *s == '/'; --s)
602 *s = 0;
603
604 data->alt->got_indices = 0;
605 data->alt->packs = NULL;
606 data->alt->next = NULL;
607 data->got_alternates = -1;
608
609 walker->corrupt_object_found = 0;
610 walker->fetch = fetch;
611 walker->fetch_ref = fetch_ref;
612 walker->prefetch = prefetch;
613 walker->cleanup = cleanup;
614 walker->data = data;
615
616 add_fill_function(walker, (int (*)(void *)) fill_active_slot);
617
618 return walker;
619 }
620