Verify Content-Type from smart HTTP servers
[git] / http.c
1 #include "http.h"
2 #include "pack.h"
3 #include "sideband.h"
4 #include "run-command.h"
5 #include "url.h"
6 #include "credential.h"
7 #include "version.h"
8
9 int active_requests;
10 int http_is_verbose;
11 size_t http_post_buffer = 16 * LARGE_PACKET_MAX;
12
13 #if LIBCURL_VERSION_NUM >= 0x070a06
14 #define LIBCURL_CAN_HANDLE_AUTH_ANY
15 #endif
16
17 static int min_curl_sessions = 1;
18 static int curl_session_count;
19 #ifdef USE_CURL_MULTI
20 static int max_requests = -1;
21 static CURLM *curlm;
22 #endif
23 #ifndef NO_CURL_EASY_DUPHANDLE
24 static CURL *curl_default;
25 #endif
26
27 #define PREV_BUF_SIZE 4096
28 #define RANGE_HEADER_SIZE 30
29
30 char curl_errorstr[CURL_ERROR_SIZE];
31
32 static int curl_ssl_verify = -1;
33 static const char *ssl_cert;
34 #if LIBCURL_VERSION_NUM >= 0x070903
35 static const char *ssl_key;
36 #endif
37 #if LIBCURL_VERSION_NUM >= 0x070908
38 static const char *ssl_capath;
39 #endif
40 static const char *ssl_cainfo;
41 static long curl_low_speed_limit = -1;
42 static long curl_low_speed_time = -1;
43 static int curl_ftp_no_epsv;
44 static const char *curl_http_proxy;
45 static const char *curl_cookie_file;
46 static struct credential http_auth = CREDENTIAL_INIT;
47 static int http_proactive_auth;
48 static const char *user_agent;
49
50 #if LIBCURL_VERSION_NUM >= 0x071700
51 /* Use CURLOPT_KEYPASSWD as is */
52 #elif LIBCURL_VERSION_NUM >= 0x070903
53 #define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
54 #else
55 #define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
56 #endif
57
58 static struct credential cert_auth = CREDENTIAL_INIT;
59 static int ssl_cert_password_required;
60
61 static struct curl_slist *pragma_header;
62 static struct curl_slist *no_pragma_header;
63
64 static struct active_request_slot *active_queue_head;
65
66 size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
67 {
68         size_t size = eltsize * nmemb;
69         struct buffer *buffer = buffer_;
70
71         if (size > buffer->buf.len - buffer->posn)
72                 size = buffer->buf.len - buffer->posn;
73         memcpy(ptr, buffer->buf.buf + buffer->posn, size);
74         buffer->posn += size;
75
76         return size;
77 }
78
79 #ifndef NO_CURL_IOCTL
80 curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
81 {
82         struct buffer *buffer = clientp;
83
84         switch (cmd) {
85         case CURLIOCMD_NOP:
86                 return CURLIOE_OK;
87
88         case CURLIOCMD_RESTARTREAD:
89                 buffer->posn = 0;
90                 return CURLIOE_OK;
91
92         default:
93                 return CURLIOE_UNKNOWNCMD;
94         }
95 }
96 #endif
97
98 size_t fwrite_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
99 {
100         size_t size = eltsize * nmemb;
101         struct strbuf *buffer = buffer_;
102
103         strbuf_add(buffer, ptr, size);
104         return size;
105 }
106
107 size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
108 {
109         return eltsize * nmemb;
110 }
111
112 #ifdef USE_CURL_MULTI
113 static void process_curl_messages(void)
114 {
115         int num_messages;
116         struct active_request_slot *slot;
117         CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
118
119         while (curl_message != NULL) {
120                 if (curl_message->msg == CURLMSG_DONE) {
121                         int curl_result = curl_message->data.result;
122                         slot = active_queue_head;
123                         while (slot != NULL &&
124                                slot->curl != curl_message->easy_handle)
125                                 slot = slot->next;
126                         if (slot != NULL) {
127                                 curl_multi_remove_handle(curlm, slot->curl);
128                                 slot->curl_result = curl_result;
129                                 finish_active_slot(slot);
130                         } else {
131                                 fprintf(stderr, "Received DONE message for unknown request!\n");
132                         }
133                 } else {
134                         fprintf(stderr, "Unknown CURL message received: %d\n",
135                                 (int)curl_message->msg);
136                 }
137                 curl_message = curl_multi_info_read(curlm, &num_messages);
138         }
139 }
140 #endif
141
142 static int http_options(const char *var, const char *value, void *cb)
143 {
144         if (!strcmp("http.sslverify", var)) {
145                 curl_ssl_verify = git_config_bool(var, value);
146                 return 0;
147         }
148         if (!strcmp("http.sslcert", var))
149                 return git_config_string(&ssl_cert, var, value);
150 #if LIBCURL_VERSION_NUM >= 0x070903
151         if (!strcmp("http.sslkey", var))
152                 return git_config_string(&ssl_key, var, value);
153 #endif
154 #if LIBCURL_VERSION_NUM >= 0x070908
155         if (!strcmp("http.sslcapath", var))
156                 return git_config_string(&ssl_capath, var, value);
157 #endif
158         if (!strcmp("http.sslcainfo", var))
159                 return git_config_string(&ssl_cainfo, var, value);
160         if (!strcmp("http.sslcertpasswordprotected", var)) {
161                 if (git_config_bool(var, value))
162                         ssl_cert_password_required = 1;
163                 return 0;
164         }
165         if (!strcmp("http.minsessions", var)) {
166                 min_curl_sessions = git_config_int(var, value);
167 #ifndef USE_CURL_MULTI
168                 if (min_curl_sessions > 1)
169                         min_curl_sessions = 1;
170 #endif
171                 return 0;
172         }
173 #ifdef USE_CURL_MULTI
174         if (!strcmp("http.maxrequests", var)) {
175                 max_requests = git_config_int(var, value);
176                 return 0;
177         }
178 #endif
179         if (!strcmp("http.lowspeedlimit", var)) {
180                 curl_low_speed_limit = (long)git_config_int(var, value);
181                 return 0;
182         }
183         if (!strcmp("http.lowspeedtime", var)) {
184                 curl_low_speed_time = (long)git_config_int(var, value);
185                 return 0;
186         }
187
188         if (!strcmp("http.noepsv", var)) {
189                 curl_ftp_no_epsv = git_config_bool(var, value);
190                 return 0;
191         }
192         if (!strcmp("http.proxy", var))
193                 return git_config_string(&curl_http_proxy, var, value);
194
195         if (!strcmp("http.cookiefile", var))
196                 return git_config_string(&curl_cookie_file, var, value);
197
198         if (!strcmp("http.postbuffer", var)) {
199                 http_post_buffer = git_config_int(var, value);
200                 if (http_post_buffer < LARGE_PACKET_MAX)
201                         http_post_buffer = LARGE_PACKET_MAX;
202                 return 0;
203         }
204
205         if (!strcmp("http.useragent", var))
206                 return git_config_string(&user_agent, var, value);
207
208         /* Fall back on the default ones */
209         return git_default_config(var, value, cb);
210 }
211
212 static void init_curl_http_auth(CURL *result)
213 {
214         if (!http_auth.username)
215                 return;
216
217         credential_fill(&http_auth);
218
219 #if LIBCURL_VERSION_NUM >= 0x071301
220         curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
221         curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
222 #else
223         {
224                 static struct strbuf up = STRBUF_INIT;
225                 strbuf_reset(&up);
226                 strbuf_addf(&up, "%s:%s",
227                             http_auth.username, http_auth.password);
228                 curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
229         }
230 #endif
231 }
232
233 static int has_cert_password(void)
234 {
235         if (ssl_cert == NULL || ssl_cert_password_required != 1)
236                 return 0;
237         if (!cert_auth.password) {
238                 cert_auth.protocol = xstrdup("cert");
239                 cert_auth.username = xstrdup("");
240                 cert_auth.path = xstrdup(ssl_cert);
241                 credential_fill(&cert_auth);
242         }
243         return 1;
244 }
245
246 static CURL *get_curl_handle(void)
247 {
248         CURL *result = curl_easy_init();
249
250         if (!curl_ssl_verify) {
251                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
252                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
253         } else {
254                 /* Verify authenticity of the peer's certificate */
255                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
256                 /* The name in the cert must match whom we tried to connect */
257                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
258         }
259
260 #if LIBCURL_VERSION_NUM >= 0x070907
261         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
262 #endif
263 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
264         curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
265 #endif
266
267         if (http_proactive_auth)
268                 init_curl_http_auth(result);
269
270         if (ssl_cert != NULL)
271                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
272         if (has_cert_password())
273                 curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
274 #if LIBCURL_VERSION_NUM >= 0x070903
275         if (ssl_key != NULL)
276                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
277 #endif
278 #if LIBCURL_VERSION_NUM >= 0x070908
279         if (ssl_capath != NULL)
280                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
281 #endif
282         if (ssl_cainfo != NULL)
283                 curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
284         curl_easy_setopt(result, CURLOPT_FAILONERROR, 1);
285
286         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
287                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
288                                  curl_low_speed_limit);
289                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
290                                  curl_low_speed_time);
291         }
292
293         curl_easy_setopt(result, CURLOPT_FOLLOWLOCATION, 1);
294 #if LIBCURL_VERSION_NUM >= 0x071301
295         curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
296 #elif LIBCURL_VERSION_NUM >= 0x071101
297         curl_easy_setopt(result, CURLOPT_POST301, 1);
298 #endif
299
300         if (getenv("GIT_CURL_VERBOSE"))
301                 curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
302
303         curl_easy_setopt(result, CURLOPT_USERAGENT,
304                 user_agent ? user_agent : git_user_agent());
305
306         if (curl_ftp_no_epsv)
307                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
308
309         if (curl_http_proxy) {
310                 curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
311                 curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
312         }
313
314         return result;
315 }
316
317 static void set_from_env(const char **var, const char *envname)
318 {
319         const char *val = getenv(envname);
320         if (val)
321                 *var = val;
322 }
323
324 void http_init(struct remote *remote, const char *url, int proactive_auth)
325 {
326         char *low_speed_limit;
327         char *low_speed_time;
328
329         http_is_verbose = 0;
330
331         git_config(http_options, NULL);
332
333         curl_global_init(CURL_GLOBAL_ALL);
334
335         http_proactive_auth = proactive_auth;
336
337         if (remote && remote->http_proxy)
338                 curl_http_proxy = xstrdup(remote->http_proxy);
339
340         pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
341         no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
342
343 #ifdef USE_CURL_MULTI
344         {
345                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
346                 if (http_max_requests != NULL)
347                         max_requests = atoi(http_max_requests);
348         }
349
350         curlm = curl_multi_init();
351         if (curlm == NULL) {
352                 fprintf(stderr, "Error creating curl multi handle.\n");
353                 exit(1);
354         }
355 #endif
356
357         if (getenv("GIT_SSL_NO_VERIFY"))
358                 curl_ssl_verify = 0;
359
360         set_from_env(&ssl_cert, "GIT_SSL_CERT");
361 #if LIBCURL_VERSION_NUM >= 0x070903
362         set_from_env(&ssl_key, "GIT_SSL_KEY");
363 #endif
364 #if LIBCURL_VERSION_NUM >= 0x070908
365         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
366 #endif
367         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
368
369         set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
370
371         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
372         if (low_speed_limit != NULL)
373                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
374         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
375         if (low_speed_time != NULL)
376                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
377
378         if (curl_ssl_verify == -1)
379                 curl_ssl_verify = 1;
380
381         curl_session_count = 0;
382 #ifdef USE_CURL_MULTI
383         if (max_requests < 1)
384                 max_requests = DEFAULT_MAX_REQUESTS;
385 #endif
386
387         if (getenv("GIT_CURL_FTP_NO_EPSV"))
388                 curl_ftp_no_epsv = 1;
389
390         if (url) {
391                 credential_from_url(&http_auth, url);
392                 if (!ssl_cert_password_required &&
393                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
394                     !prefixcmp(url, "https://"))
395                         ssl_cert_password_required = 1;
396         }
397
398 #ifndef NO_CURL_EASY_DUPHANDLE
399         curl_default = get_curl_handle();
400 #endif
401 }
402
403 void http_cleanup(void)
404 {
405         struct active_request_slot *slot = active_queue_head;
406
407         while (slot != NULL) {
408                 struct active_request_slot *next = slot->next;
409                 if (slot->curl != NULL) {
410 #ifdef USE_CURL_MULTI
411                         curl_multi_remove_handle(curlm, slot->curl);
412 #endif
413                         curl_easy_cleanup(slot->curl);
414                 }
415                 free(slot);
416                 slot = next;
417         }
418         active_queue_head = NULL;
419
420 #ifndef NO_CURL_EASY_DUPHANDLE
421         curl_easy_cleanup(curl_default);
422 #endif
423
424 #ifdef USE_CURL_MULTI
425         curl_multi_cleanup(curlm);
426 #endif
427         curl_global_cleanup();
428
429         curl_slist_free_all(pragma_header);
430         pragma_header = NULL;
431
432         curl_slist_free_all(no_pragma_header);
433         no_pragma_header = NULL;
434
435         if (curl_http_proxy) {
436                 free((void *)curl_http_proxy);
437                 curl_http_proxy = NULL;
438         }
439
440         if (cert_auth.password != NULL) {
441                 memset(cert_auth.password, 0, strlen(cert_auth.password));
442                 free(cert_auth.password);
443                 cert_auth.password = NULL;
444         }
445         ssl_cert_password_required = 0;
446 }
447
448 struct active_request_slot *get_active_slot(void)
449 {
450         struct active_request_slot *slot = active_queue_head;
451         struct active_request_slot *newslot;
452
453 #ifdef USE_CURL_MULTI
454         int num_transfers;
455
456         /* Wait for a slot to open up if the queue is full */
457         while (active_requests >= max_requests) {
458                 curl_multi_perform(curlm, &num_transfers);
459                 if (num_transfers < active_requests)
460                         process_curl_messages();
461         }
462 #endif
463
464         while (slot != NULL && slot->in_use)
465                 slot = slot->next;
466
467         if (slot == NULL) {
468                 newslot = xmalloc(sizeof(*newslot));
469                 newslot->curl = NULL;
470                 newslot->in_use = 0;
471                 newslot->next = NULL;
472
473                 slot = active_queue_head;
474                 if (slot == NULL) {
475                         active_queue_head = newslot;
476                 } else {
477                         while (slot->next != NULL)
478                                 slot = slot->next;
479                         slot->next = newslot;
480                 }
481                 slot = newslot;
482         }
483
484         if (slot->curl == NULL) {
485 #ifdef NO_CURL_EASY_DUPHANDLE
486                 slot->curl = get_curl_handle();
487 #else
488                 slot->curl = curl_easy_duphandle(curl_default);
489 #endif
490                 curl_session_count++;
491         }
492
493         active_requests++;
494         slot->in_use = 1;
495         slot->results = NULL;
496         slot->finished = NULL;
497         slot->callback_data = NULL;
498         slot->callback_func = NULL;
499         curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
500         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
501         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
502         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
503         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
504         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
505         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
506         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
507         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
508         if (http_auth.password)
509                 init_curl_http_auth(slot->curl);
510
511         return slot;
512 }
513
514 int start_active_slot(struct active_request_slot *slot)
515 {
516 #ifdef USE_CURL_MULTI
517         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
518         int num_transfers;
519
520         if (curlm_result != CURLM_OK &&
521             curlm_result != CURLM_CALL_MULTI_PERFORM) {
522                 active_requests--;
523                 slot->in_use = 0;
524                 return 0;
525         }
526
527         /*
528          * We know there must be something to do, since we just added
529          * something.
530          */
531         curl_multi_perform(curlm, &num_transfers);
532 #endif
533         return 1;
534 }
535
536 #ifdef USE_CURL_MULTI
537 struct fill_chain {
538         void *data;
539         int (*fill)(void *);
540         struct fill_chain *next;
541 };
542
543 static struct fill_chain *fill_cfg;
544
545 void add_fill_function(void *data, int (*fill)(void *))
546 {
547         struct fill_chain *new = xmalloc(sizeof(*new));
548         struct fill_chain **linkp = &fill_cfg;
549         new->data = data;
550         new->fill = fill;
551         new->next = NULL;
552         while (*linkp)
553                 linkp = &(*linkp)->next;
554         *linkp = new;
555 }
556
557 void fill_active_slots(void)
558 {
559         struct active_request_slot *slot = active_queue_head;
560
561         while (active_requests < max_requests) {
562                 struct fill_chain *fill;
563                 for (fill = fill_cfg; fill; fill = fill->next)
564                         if (fill->fill(fill->data))
565                                 break;
566
567                 if (!fill)
568                         break;
569         }
570
571         while (slot != NULL) {
572                 if (!slot->in_use && slot->curl != NULL
573                         && curl_session_count > min_curl_sessions) {
574                         curl_easy_cleanup(slot->curl);
575                         slot->curl = NULL;
576                         curl_session_count--;
577                 }
578                 slot = slot->next;
579         }
580 }
581
582 void step_active_slots(void)
583 {
584         int num_transfers;
585         CURLMcode curlm_result;
586
587         do {
588                 curlm_result = curl_multi_perform(curlm, &num_transfers);
589         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
590         if (num_transfers < active_requests) {
591                 process_curl_messages();
592                 fill_active_slots();
593         }
594 }
595 #endif
596
597 void run_active_slot(struct active_request_slot *slot)
598 {
599 #ifdef USE_CURL_MULTI
600         fd_set readfds;
601         fd_set writefds;
602         fd_set excfds;
603         int max_fd;
604         struct timeval select_timeout;
605         int finished = 0;
606
607         slot->finished = &finished;
608         while (!finished) {
609                 step_active_slots();
610
611                 if (slot->in_use) {
612 #if LIBCURL_VERSION_NUM >= 0x070f04
613                         long curl_timeout;
614                         curl_multi_timeout(curlm, &curl_timeout);
615                         if (curl_timeout == 0) {
616                                 continue;
617                         } else if (curl_timeout == -1) {
618                                 select_timeout.tv_sec  = 0;
619                                 select_timeout.tv_usec = 50000;
620                         } else {
621                                 select_timeout.tv_sec  =  curl_timeout / 1000;
622                                 select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
623                         }
624 #else
625                         select_timeout.tv_sec  = 0;
626                         select_timeout.tv_usec = 50000;
627 #endif
628
629                         max_fd = -1;
630                         FD_ZERO(&readfds);
631                         FD_ZERO(&writefds);
632                         FD_ZERO(&excfds);
633                         curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
634
635                         /*
636                          * It can happen that curl_multi_timeout returns a pathologically
637                          * long timeout when curl_multi_fdset returns no file descriptors
638                          * to read.  See commit message for more details.
639                          */
640                         if (max_fd < 0 &&
641                             (select_timeout.tv_sec > 0 ||
642                              select_timeout.tv_usec > 50000)) {
643                                 select_timeout.tv_sec  = 0;
644                                 select_timeout.tv_usec = 50000;
645                         }
646
647                         select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
648                 }
649         }
650 #else
651         while (slot->in_use) {
652                 slot->curl_result = curl_easy_perform(slot->curl);
653                 finish_active_slot(slot);
654         }
655 #endif
656 }
657
658 static void closedown_active_slot(struct active_request_slot *slot)
659 {
660         active_requests--;
661         slot->in_use = 0;
662 }
663
664 static void release_active_slot(struct active_request_slot *slot)
665 {
666         closedown_active_slot(slot);
667         if (slot->curl && curl_session_count > min_curl_sessions) {
668 #ifdef USE_CURL_MULTI
669                 curl_multi_remove_handle(curlm, slot->curl);
670 #endif
671                 curl_easy_cleanup(slot->curl);
672                 slot->curl = NULL;
673                 curl_session_count--;
674         }
675 #ifdef USE_CURL_MULTI
676         fill_active_slots();
677 #endif
678 }
679
680 void finish_active_slot(struct active_request_slot *slot)
681 {
682         closedown_active_slot(slot);
683         curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
684
685         if (slot->finished != NULL)
686                 (*slot->finished) = 1;
687
688         /* Store slot results so they can be read after the slot is reused */
689         if (slot->results != NULL) {
690                 slot->results->curl_result = slot->curl_result;
691                 slot->results->http_code = slot->http_code;
692         }
693
694         /* Run callback if appropriate */
695         if (slot->callback_func != NULL)
696                 slot->callback_func(slot->callback_data);
697 }
698
699 void finish_all_active_slots(void)
700 {
701         struct active_request_slot *slot = active_queue_head;
702
703         while (slot != NULL)
704                 if (slot->in_use) {
705                         run_active_slot(slot);
706                         slot = active_queue_head;
707                 } else {
708                         slot = slot->next;
709                 }
710 }
711
712 /* Helpers for modifying and creating URLs */
713 static inline int needs_quote(int ch)
714 {
715         if (((ch >= 'A') && (ch <= 'Z'))
716                         || ((ch >= 'a') && (ch <= 'z'))
717                         || ((ch >= '0') && (ch <= '9'))
718                         || (ch == '/')
719                         || (ch == '-')
720                         || (ch == '.'))
721                 return 0;
722         return 1;
723 }
724
725 static char *quote_ref_url(const char *base, const char *ref)
726 {
727         struct strbuf buf = STRBUF_INIT;
728         const char *cp;
729         int ch;
730
731         end_url_with_slash(&buf, base);
732
733         for (cp = ref; (ch = *cp) != 0; cp++)
734                 if (needs_quote(ch))
735                         strbuf_addf(&buf, "%%%02x", ch);
736                 else
737                         strbuf_addch(&buf, *cp);
738
739         return strbuf_detach(&buf, NULL);
740 }
741
742 void append_remote_object_url(struct strbuf *buf, const char *url,
743                               const char *hex,
744                               int only_two_digit_prefix)
745 {
746         end_url_with_slash(buf, url);
747
748         strbuf_addf(buf, "objects/%.*s/", 2, hex);
749         if (!only_two_digit_prefix)
750                 strbuf_addf(buf, "%s", hex+2);
751 }
752
753 char *get_remote_object_url(const char *url, const char *hex,
754                             int only_two_digit_prefix)
755 {
756         struct strbuf buf = STRBUF_INIT;
757         append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
758         return strbuf_detach(&buf, NULL);
759 }
760
761 int handle_curl_result(struct slot_results *results)
762 {
763         if (results->curl_result == CURLE_OK) {
764                 credential_approve(&http_auth);
765                 return HTTP_OK;
766         } else if (missing_target(results))
767                 return HTTP_MISSING_TARGET;
768         else if (results->http_code == 401) {
769                 if (http_auth.username && http_auth.password) {
770                         credential_reject(&http_auth);
771                         return HTTP_NOAUTH;
772                 } else {
773                         credential_fill(&http_auth);
774                         return HTTP_REAUTH;
775                 }
776         } else {
777 #if LIBCURL_VERSION_NUM >= 0x070c00
778                 if (!curl_errorstr[0])
779                         strlcpy(curl_errorstr,
780                                 curl_easy_strerror(results->curl_result),
781                                 sizeof(curl_errorstr));
782 #endif
783                 return HTTP_ERROR;
784         }
785 }
786
787 /* http_request() targets */
788 #define HTTP_REQUEST_STRBUF     0
789 #define HTTP_REQUEST_FILE       1
790
791 static int http_request(const char *url, struct strbuf *type,
792                         void *result, int target, int options)
793 {
794         struct active_request_slot *slot;
795         struct slot_results results;
796         struct curl_slist *headers = NULL;
797         struct strbuf buf = STRBUF_INIT;
798         int ret;
799
800         slot = get_active_slot();
801         slot->results = &results;
802         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
803
804         if (result == NULL) {
805                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
806         } else {
807                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
808                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
809
810                 if (target == HTTP_REQUEST_FILE) {
811                         long posn = ftell(result);
812                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
813                                          fwrite);
814                         if (posn > 0) {
815                                 strbuf_addf(&buf, "Range: bytes=%ld-", posn);
816                                 headers = curl_slist_append(headers, buf.buf);
817                                 strbuf_reset(&buf);
818                         }
819                 } else
820                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
821                                          fwrite_buffer);
822         }
823
824         strbuf_addstr(&buf, "Pragma:");
825         if (options & HTTP_NO_CACHE)
826                 strbuf_addstr(&buf, " no-cache");
827
828         headers = curl_slist_append(headers, buf.buf);
829
830         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
831         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
832         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "gzip");
833
834         if (start_active_slot(slot)) {
835                 run_active_slot(slot);
836                 ret = handle_curl_result(&results);
837         } else {
838                 error("Unable to start HTTP request for %s", url);
839                 ret = HTTP_START_FAILED;
840         }
841
842         if (type) {
843                 char *t;
844                 curl_easy_getinfo(slot->curl, CURLINFO_CONTENT_TYPE, &t);
845                 if (t)
846                         strbuf_addstr(type, t);
847         }
848
849         curl_slist_free_all(headers);
850         strbuf_release(&buf);
851
852         return ret;
853 }
854
855 static int http_request_reauth(const char *url,
856                                struct strbuf *type,
857                                void *result, int target,
858                                int options)
859 {
860         int ret = http_request(url, type, result, target, options);
861         if (ret != HTTP_REAUTH)
862                 return ret;
863         return http_request(url, type, result, target, options);
864 }
865
866 int http_get_strbuf(const char *url,
867                     struct strbuf *type,
868                     struct strbuf *result, int options)
869 {
870         return http_request_reauth(url, type, result,
871                                    HTTP_REQUEST_STRBUF, options);
872 }
873
874 /*
875  * Downloads a URL and stores the result in the given file.
876  *
877  * If a previous interrupted download is detected (i.e. a previous temporary
878  * file is still around) the download is resumed.
879  */
880 static int http_get_file(const char *url, const char *filename, int options)
881 {
882         int ret;
883         struct strbuf tmpfile = STRBUF_INIT;
884         FILE *result;
885
886         strbuf_addf(&tmpfile, "%s.temp", filename);
887         result = fopen(tmpfile.buf, "a");
888         if (! result) {
889                 error("Unable to open local file %s", tmpfile.buf);
890                 ret = HTTP_ERROR;
891                 goto cleanup;
892         }
893
894         ret = http_request_reauth(url, NULL, result, HTTP_REQUEST_FILE, options);
895         fclose(result);
896
897         if ((ret == HTTP_OK) && move_temp_to_file(tmpfile.buf, filename))
898                 ret = HTTP_ERROR;
899 cleanup:
900         strbuf_release(&tmpfile);
901         return ret;
902 }
903
904 int http_error(const char *url, int ret)
905 {
906         /* http_request has already handled HTTP_START_FAILED. */
907         if (ret != HTTP_START_FAILED)
908                 error("%s while accessing %s", curl_errorstr, url);
909
910         return ret;
911 }
912
913 int http_fetch_ref(const char *base, struct ref *ref)
914 {
915         char *url;
916         struct strbuf buffer = STRBUF_INIT;
917         int ret = -1;
918
919         url = quote_ref_url(base, ref->name);
920         if (http_get_strbuf(url, NULL, &buffer, HTTP_NO_CACHE) == HTTP_OK) {
921                 strbuf_rtrim(&buffer);
922                 if (buffer.len == 40)
923                         ret = get_sha1_hex(buffer.buf, ref->old_sha1);
924                 else if (!prefixcmp(buffer.buf, "ref: ")) {
925                         ref->symref = xstrdup(buffer.buf + 5);
926                         ret = 0;
927                 }
928         }
929
930         strbuf_release(&buffer);
931         free(url);
932         return ret;
933 }
934
935 /* Helpers for fetching packs */
936 static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
937 {
938         char *url, *tmp;
939         struct strbuf buf = STRBUF_INIT;
940
941         if (http_is_verbose)
942                 fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
943
944         end_url_with_slash(&buf, base_url);
945         strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
946         url = strbuf_detach(&buf, NULL);
947
948         strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
949         tmp = strbuf_detach(&buf, NULL);
950
951         if (http_get_file(url, tmp, 0) != HTTP_OK) {
952                 error("Unable to get pack index %s", url);
953                 free(tmp);
954                 tmp = NULL;
955         }
956
957         free(url);
958         return tmp;
959 }
960
961 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
962         unsigned char *sha1, const char *base_url)
963 {
964         struct packed_git *new_pack;
965         char *tmp_idx = NULL;
966         int ret;
967
968         if (has_pack_index(sha1)) {
969                 new_pack = parse_pack_index(sha1, NULL);
970                 if (!new_pack)
971                         return -1; /* parse_pack_index() already issued error message */
972                 goto add_pack;
973         }
974
975         tmp_idx = fetch_pack_index(sha1, base_url);
976         if (!tmp_idx)
977                 return -1;
978
979         new_pack = parse_pack_index(sha1, tmp_idx);
980         if (!new_pack) {
981                 unlink(tmp_idx);
982                 free(tmp_idx);
983
984                 return -1; /* parse_pack_index() already issued error message */
985         }
986
987         ret = verify_pack_index(new_pack);
988         if (!ret) {
989                 close_pack_index(new_pack);
990                 ret = move_temp_to_file(tmp_idx, sha1_pack_index_name(sha1));
991         }
992         free(tmp_idx);
993         if (ret)
994                 return -1;
995
996 add_pack:
997         new_pack->next = *packs_head;
998         *packs_head = new_pack;
999         return 0;
1000 }
1001
1002 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
1003 {
1004         int ret = 0, i = 0;
1005         char *url, *data;
1006         struct strbuf buf = STRBUF_INIT;
1007         unsigned char sha1[20];
1008
1009         end_url_with_slash(&buf, base_url);
1010         strbuf_addstr(&buf, "objects/info/packs");
1011         url = strbuf_detach(&buf, NULL);
1012
1013         ret = http_get_strbuf(url, NULL, &buf, HTTP_NO_CACHE);
1014         if (ret != HTTP_OK)
1015                 goto cleanup;
1016
1017         data = buf.buf;
1018         while (i < buf.len) {
1019                 switch (data[i]) {
1020                 case 'P':
1021                         i++;
1022                         if (i + 52 <= buf.len &&
1023                             !prefixcmp(data + i, " pack-") &&
1024                             !prefixcmp(data + i + 46, ".pack\n")) {
1025                                 get_sha1_hex(data + i + 6, sha1);
1026                                 fetch_and_setup_pack_index(packs_head, sha1,
1027                                                       base_url);
1028                                 i += 51;
1029                                 break;
1030                         }
1031                 default:
1032                         while (i < buf.len && data[i] != '\n')
1033                                 i++;
1034                 }
1035                 i++;
1036         }
1037
1038 cleanup:
1039         free(url);
1040         return ret;
1041 }
1042
1043 void release_http_pack_request(struct http_pack_request *preq)
1044 {
1045         if (preq->packfile != NULL) {
1046                 fclose(preq->packfile);
1047                 preq->packfile = NULL;
1048         }
1049         if (preq->range_header != NULL) {
1050                 curl_slist_free_all(preq->range_header);
1051                 preq->range_header = NULL;
1052         }
1053         preq->slot = NULL;
1054         free(preq->url);
1055 }
1056
1057 int finish_http_pack_request(struct http_pack_request *preq)
1058 {
1059         struct packed_git **lst;
1060         struct packed_git *p = preq->target;
1061         char *tmp_idx;
1062         struct child_process ip;
1063         const char *ip_argv[8];
1064
1065         close_pack_index(p);
1066
1067         fclose(preq->packfile);
1068         preq->packfile = NULL;
1069
1070         lst = preq->lst;
1071         while (*lst != p)
1072                 lst = &((*lst)->next);
1073         *lst = (*lst)->next;
1074
1075         tmp_idx = xstrdup(preq->tmpfile);
1076         strcpy(tmp_idx + strlen(tmp_idx) - strlen(".pack.temp"),
1077                ".idx.temp");
1078
1079         ip_argv[0] = "index-pack";
1080         ip_argv[1] = "-o";
1081         ip_argv[2] = tmp_idx;
1082         ip_argv[3] = preq->tmpfile;
1083         ip_argv[4] = NULL;
1084
1085         memset(&ip, 0, sizeof(ip));
1086         ip.argv = ip_argv;
1087         ip.git_cmd = 1;
1088         ip.no_stdin = 1;
1089         ip.no_stdout = 1;
1090
1091         if (run_command(&ip)) {
1092                 unlink(preq->tmpfile);
1093                 unlink(tmp_idx);
1094                 free(tmp_idx);
1095                 return -1;
1096         }
1097
1098         unlink(sha1_pack_index_name(p->sha1));
1099
1100         if (move_temp_to_file(preq->tmpfile, sha1_pack_name(p->sha1))
1101          || move_temp_to_file(tmp_idx, sha1_pack_index_name(p->sha1))) {
1102                 free(tmp_idx);
1103                 return -1;
1104         }
1105
1106         install_packed_git(p);
1107         free(tmp_idx);
1108         return 0;
1109 }
1110
1111 struct http_pack_request *new_http_pack_request(
1112         struct packed_git *target, const char *base_url)
1113 {
1114         long prev_posn = 0;
1115         char range[RANGE_HEADER_SIZE];
1116         struct strbuf buf = STRBUF_INIT;
1117         struct http_pack_request *preq;
1118
1119         preq = xcalloc(1, sizeof(*preq));
1120         preq->target = target;
1121
1122         end_url_with_slash(&buf, base_url);
1123         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
1124                 sha1_to_hex(target->sha1));
1125         preq->url = strbuf_detach(&buf, NULL);
1126
1127         snprintf(preq->tmpfile, sizeof(preq->tmpfile), "%s.temp",
1128                 sha1_pack_name(target->sha1));
1129         preq->packfile = fopen(preq->tmpfile, "a");
1130         if (!preq->packfile) {
1131                 error("Unable to open local file %s for pack",
1132                       preq->tmpfile);
1133                 goto abort;
1134         }
1135
1136         preq->slot = get_active_slot();
1137         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
1138         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
1139         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
1140         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1141                 no_pragma_header);
1142
1143         /*
1144          * If there is data present from a previous transfer attempt,
1145          * resume where it left off
1146          */
1147         prev_posn = ftell(preq->packfile);
1148         if (prev_posn>0) {
1149                 if (http_is_verbose)
1150                         fprintf(stderr,
1151                                 "Resuming fetch of pack %s at byte %ld\n",
1152                                 sha1_to_hex(target->sha1), prev_posn);
1153                 sprintf(range, "Range: bytes=%ld-", prev_posn);
1154                 preq->range_header = curl_slist_append(NULL, range);
1155                 curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1156                         preq->range_header);
1157         }
1158
1159         return preq;
1160
1161 abort:
1162         free(preq->url);
1163         free(preq);
1164         return NULL;
1165 }
1166
1167 /* Helpers for fetching objects (loose) */
1168 static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
1169                                void *data)
1170 {
1171         unsigned char expn[4096];
1172         size_t size = eltsize * nmemb;
1173         int posn = 0;
1174         struct http_object_request *freq =
1175                 (struct http_object_request *)data;
1176         do {
1177                 ssize_t retval = xwrite(freq->localfile,
1178                                         (char *) ptr + posn, size - posn);
1179                 if (retval < 0)
1180                         return posn;
1181                 posn += retval;
1182         } while (posn < size);
1183
1184         freq->stream.avail_in = size;
1185         freq->stream.next_in = (void *)ptr;
1186         do {
1187                 freq->stream.next_out = expn;
1188                 freq->stream.avail_out = sizeof(expn);
1189                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
1190                 git_SHA1_Update(&freq->c, expn,
1191                                 sizeof(expn) - freq->stream.avail_out);
1192         } while (freq->stream.avail_in && freq->zret == Z_OK);
1193         return size;
1194 }
1195
1196 struct http_object_request *new_http_object_request(const char *base_url,
1197         unsigned char *sha1)
1198 {
1199         char *hex = sha1_to_hex(sha1);
1200         char *filename;
1201         char prevfile[PATH_MAX];
1202         int prevlocal;
1203         char prev_buf[PREV_BUF_SIZE];
1204         ssize_t prev_read = 0;
1205         long prev_posn = 0;
1206         char range[RANGE_HEADER_SIZE];
1207         struct curl_slist *range_header = NULL;
1208         struct http_object_request *freq;
1209
1210         freq = xcalloc(1, sizeof(*freq));
1211         hashcpy(freq->sha1, sha1);
1212         freq->localfile = -1;
1213
1214         filename = sha1_file_name(sha1);
1215         snprintf(freq->tmpfile, sizeof(freq->tmpfile),
1216                  "%s.temp", filename);
1217
1218         snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
1219         unlink_or_warn(prevfile);
1220         rename(freq->tmpfile, prevfile);
1221         unlink_or_warn(freq->tmpfile);
1222
1223         if (freq->localfile != -1)
1224                 error("fd leakage in start: %d", freq->localfile);
1225         freq->localfile = open(freq->tmpfile,
1226                                O_WRONLY | O_CREAT | O_EXCL, 0666);
1227         /*
1228          * This could have failed due to the "lazy directory creation";
1229          * try to mkdir the last path component.
1230          */
1231         if (freq->localfile < 0 && errno == ENOENT) {
1232                 char *dir = strrchr(freq->tmpfile, '/');
1233                 if (dir) {
1234                         *dir = 0;
1235                         mkdir(freq->tmpfile, 0777);
1236                         *dir = '/';
1237                 }
1238                 freq->localfile = open(freq->tmpfile,
1239                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
1240         }
1241
1242         if (freq->localfile < 0) {
1243                 error("Couldn't create temporary file %s: %s",
1244                       freq->tmpfile, strerror(errno));
1245                 goto abort;
1246         }
1247
1248         git_inflate_init(&freq->stream);
1249
1250         git_SHA1_Init(&freq->c);
1251
1252         freq->url = get_remote_object_url(base_url, hex, 0);
1253
1254         /*
1255          * If a previous temp file is present, process what was already
1256          * fetched.
1257          */
1258         prevlocal = open(prevfile, O_RDONLY);
1259         if (prevlocal != -1) {
1260                 do {
1261                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
1262                         if (prev_read>0) {
1263                                 if (fwrite_sha1_file(prev_buf,
1264                                                      1,
1265                                                      prev_read,
1266                                                      freq) == prev_read) {
1267                                         prev_posn += prev_read;
1268                                 } else {
1269                                         prev_read = -1;
1270                                 }
1271                         }
1272                 } while (prev_read > 0);
1273                 close(prevlocal);
1274         }
1275         unlink_or_warn(prevfile);
1276
1277         /*
1278          * Reset inflate/SHA1 if there was an error reading the previous temp
1279          * file; also rewind to the beginning of the local file.
1280          */
1281         if (prev_read == -1) {
1282                 memset(&freq->stream, 0, sizeof(freq->stream));
1283                 git_inflate_init(&freq->stream);
1284                 git_SHA1_Init(&freq->c);
1285                 if (prev_posn>0) {
1286                         prev_posn = 0;
1287                         lseek(freq->localfile, 0, SEEK_SET);
1288                         if (ftruncate(freq->localfile, 0) < 0) {
1289                                 error("Couldn't truncate temporary file %s: %s",
1290                                           freq->tmpfile, strerror(errno));
1291                                 goto abort;
1292                         }
1293                 }
1294         }
1295
1296         freq->slot = get_active_slot();
1297
1298         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
1299         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
1300         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
1301         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
1302         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
1303
1304         /*
1305          * If we have successfully processed data from a previous fetch
1306          * attempt, only fetch the data we don't already have.
1307          */
1308         if (prev_posn>0) {
1309                 if (http_is_verbose)
1310                         fprintf(stderr,
1311                                 "Resuming fetch of object %s at byte %ld\n",
1312                                 hex, prev_posn);
1313                 sprintf(range, "Range: bytes=%ld-", prev_posn);
1314                 range_header = curl_slist_append(range_header, range);
1315                 curl_easy_setopt(freq->slot->curl,
1316                                  CURLOPT_HTTPHEADER, range_header);
1317         }
1318
1319         return freq;
1320
1321 abort:
1322         free(freq->url);
1323         free(freq);
1324         return NULL;
1325 }
1326
1327 void process_http_object_request(struct http_object_request *freq)
1328 {
1329         if (freq->slot == NULL)
1330                 return;
1331         freq->curl_result = freq->slot->curl_result;
1332         freq->http_code = freq->slot->http_code;
1333         freq->slot = NULL;
1334 }
1335
1336 int finish_http_object_request(struct http_object_request *freq)
1337 {
1338         struct stat st;
1339
1340         close(freq->localfile);
1341         freq->localfile = -1;
1342
1343         process_http_object_request(freq);
1344
1345         if (freq->http_code == 416) {
1346                 warning("requested range invalid; we may already have all the data.");
1347         } else if (freq->curl_result != CURLE_OK) {
1348                 if (stat(freq->tmpfile, &st) == 0)
1349                         if (st.st_size == 0)
1350                                 unlink_or_warn(freq->tmpfile);
1351                 return -1;
1352         }
1353
1354         git_inflate_end(&freq->stream);
1355         git_SHA1_Final(freq->real_sha1, &freq->c);
1356         if (freq->zret != Z_STREAM_END) {
1357                 unlink_or_warn(freq->tmpfile);
1358                 return -1;
1359         }
1360         if (hashcmp(freq->sha1, freq->real_sha1)) {
1361                 unlink_or_warn(freq->tmpfile);
1362                 return -1;
1363         }
1364         freq->rename =
1365                 move_temp_to_file(freq->tmpfile, sha1_file_name(freq->sha1));
1366
1367         return freq->rename;
1368 }
1369
1370 void abort_http_object_request(struct http_object_request *freq)
1371 {
1372         unlink_or_warn(freq->tmpfile);
1373
1374         release_http_object_request(freq);
1375 }
1376
1377 void release_http_object_request(struct http_object_request *freq)
1378 {
1379         if (freq->localfile != -1) {
1380                 close(freq->localfile);
1381                 freq->localfile = -1;
1382         }
1383         if (freq->url != NULL) {
1384                 free(freq->url);
1385                 freq->url = NULL;
1386         }
1387         if (freq->slot != NULL) {
1388                 freq->slot->callback_func = NULL;
1389                 freq->slot->callback_data = NULL;
1390                 release_active_slot(freq->slot);
1391                 freq->slot = NULL;
1392         }
1393 }