http.postbuffer: allow full range of ssize_t values
[git] / http.c
1 #include "git-compat-util.h"
2 #include "http.h"
3 #include "pack.h"
4 #include "sideband.h"
5 #include "run-command.h"
6 #include "url.h"
7 #include "urlmatch.h"
8 #include "credential.h"
9 #include "version.h"
10 #include "pkt-line.h"
11 #include "gettext.h"
12 #include "transport.h"
13
14 static struct trace_key trace_curl = TRACE_KEY_INIT(CURL);
15 #if LIBCURL_VERSION_NUM >= 0x070a08
16 long int git_curl_ipresolve = CURL_IPRESOLVE_WHATEVER;
17 #else
18 long int git_curl_ipresolve;
19 #endif
20 int active_requests;
21 int http_is_verbose;
22 ssize_t http_post_buffer = 16 * LARGE_PACKET_MAX;
23
24 #if LIBCURL_VERSION_NUM >= 0x070a06
25 #define LIBCURL_CAN_HANDLE_AUTH_ANY
26 #endif
27
28 static int min_curl_sessions = 1;
29 static int curl_session_count;
30 #ifdef USE_CURL_MULTI
31 static int max_requests = -1;
32 static CURLM *curlm;
33 #endif
34 #ifndef NO_CURL_EASY_DUPHANDLE
35 static CURL *curl_default;
36 #endif
37
38 #define PREV_BUF_SIZE 4096
39
40 char curl_errorstr[CURL_ERROR_SIZE];
41
42 static int curl_ssl_verify = -1;
43 static int curl_ssl_try;
44 static const char *ssl_cert;
45 static const char *ssl_cipherlist;
46 static const char *ssl_version;
47 static struct {
48         const char *name;
49         long ssl_version;
50 } sslversions[] = {
51         { "sslv2", CURL_SSLVERSION_SSLv2 },
52         { "sslv3", CURL_SSLVERSION_SSLv3 },
53         { "tlsv1", CURL_SSLVERSION_TLSv1 },
54 #if LIBCURL_VERSION_NUM >= 0x072200
55         { "tlsv1.0", CURL_SSLVERSION_TLSv1_0 },
56         { "tlsv1.1", CURL_SSLVERSION_TLSv1_1 },
57         { "tlsv1.2", CURL_SSLVERSION_TLSv1_2 },
58 #endif
59 };
60 #if LIBCURL_VERSION_NUM >= 0x070903
61 static const char *ssl_key;
62 #endif
63 #if LIBCURL_VERSION_NUM >= 0x070908
64 static const char *ssl_capath;
65 #endif
66 #if LIBCURL_VERSION_NUM >= 0x072c00
67 static const char *ssl_pinnedkey;
68 #endif
69 static const char *ssl_cainfo;
70 static long curl_low_speed_limit = -1;
71 static long curl_low_speed_time = -1;
72 static int curl_ftp_no_epsv;
73 static const char *curl_http_proxy;
74 static const char *curl_no_proxy;
75 static const char *http_proxy_authmethod;
76 static struct {
77         const char *name;
78         long curlauth_param;
79 } proxy_authmethods[] = {
80         { "basic", CURLAUTH_BASIC },
81         { "digest", CURLAUTH_DIGEST },
82         { "negotiate", CURLAUTH_GSSNEGOTIATE },
83         { "ntlm", CURLAUTH_NTLM },
84 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
85         { "anyauth", CURLAUTH_ANY },
86 #endif
87         /*
88          * CURLAUTH_DIGEST_IE has no corresponding command-line option in
89          * curl(1) and is not included in CURLAUTH_ANY, so we leave it out
90          * here, too
91          */
92 };
93 #if LIBCURL_VERSION_NUM >= 0x071600
94 static const char *curl_deleg;
95 static struct {
96         const char *name;
97         long curl_deleg_param;
98 } curl_deleg_levels[] = {
99         { "none", CURLGSSAPI_DELEGATION_NONE },
100         { "policy", CURLGSSAPI_DELEGATION_POLICY_FLAG },
101         { "always", CURLGSSAPI_DELEGATION_FLAG },
102 };
103 #endif
104
105 static struct credential proxy_auth = CREDENTIAL_INIT;
106 static const char *curl_proxyuserpwd;
107 static const char *curl_cookie_file;
108 static int curl_save_cookies;
109 struct credential http_auth = CREDENTIAL_INIT;
110 static int http_proactive_auth;
111 static const char *user_agent;
112 static int curl_empty_auth = -1;
113
114 enum http_follow_config http_follow_config = HTTP_FOLLOW_INITIAL;
115
116 #if LIBCURL_VERSION_NUM >= 0x071700
117 /* Use CURLOPT_KEYPASSWD as is */
118 #elif LIBCURL_VERSION_NUM >= 0x070903
119 #define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
120 #else
121 #define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
122 #endif
123
124 static struct credential cert_auth = CREDENTIAL_INIT;
125 static int ssl_cert_password_required;
126 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
127 static unsigned long http_auth_methods = CURLAUTH_ANY;
128 static int http_auth_methods_restricted;
129 /* Modes for which empty_auth cannot actually help us. */
130 static unsigned long empty_auth_useless =
131         CURLAUTH_BASIC
132 #ifdef CURLAUTH_DIGEST_IE
133         | CURLAUTH_DIGEST_IE
134 #endif
135         | CURLAUTH_DIGEST;
136 #endif
137
138 static struct curl_slist *pragma_header;
139 static struct curl_slist *no_pragma_header;
140 static struct curl_slist *extra_http_headers;
141
142 static struct active_request_slot *active_queue_head;
143
144 static char *cached_accept_language;
145
146 size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
147 {
148         size_t size = eltsize * nmemb;
149         struct buffer *buffer = buffer_;
150
151         if (size > buffer->buf.len - buffer->posn)
152                 size = buffer->buf.len - buffer->posn;
153         memcpy(ptr, buffer->buf.buf + buffer->posn, size);
154         buffer->posn += size;
155
156         return size;
157 }
158
159 #ifndef NO_CURL_IOCTL
160 curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
161 {
162         struct buffer *buffer = clientp;
163
164         switch (cmd) {
165         case CURLIOCMD_NOP:
166                 return CURLIOE_OK;
167
168         case CURLIOCMD_RESTARTREAD:
169                 buffer->posn = 0;
170                 return CURLIOE_OK;
171
172         default:
173                 return CURLIOE_UNKNOWNCMD;
174         }
175 }
176 #endif
177
178 size_t fwrite_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
179 {
180         size_t size = eltsize * nmemb;
181         struct strbuf *buffer = buffer_;
182
183         strbuf_add(buffer, ptr, size);
184         return size;
185 }
186
187 size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
188 {
189         return eltsize * nmemb;
190 }
191
192 static void closedown_active_slot(struct active_request_slot *slot)
193 {
194         active_requests--;
195         slot->in_use = 0;
196 }
197
198 static void finish_active_slot(struct active_request_slot *slot)
199 {
200         closedown_active_slot(slot);
201         curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
202
203         if (slot->finished != NULL)
204                 (*slot->finished) = 1;
205
206         /* Store slot results so they can be read after the slot is reused */
207         if (slot->results != NULL) {
208                 slot->results->curl_result = slot->curl_result;
209                 slot->results->http_code = slot->http_code;
210 #if LIBCURL_VERSION_NUM >= 0x070a08
211                 curl_easy_getinfo(slot->curl, CURLINFO_HTTPAUTH_AVAIL,
212                                   &slot->results->auth_avail);
213 #else
214                 slot->results->auth_avail = 0;
215 #endif
216
217                 curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CONNECTCODE,
218                         &slot->results->http_connectcode);
219         }
220
221         /* Run callback if appropriate */
222         if (slot->callback_func != NULL)
223                 slot->callback_func(slot->callback_data);
224 }
225
226 static void xmulti_remove_handle(struct active_request_slot *slot)
227 {
228 #ifdef USE_CURL_MULTI
229         curl_multi_remove_handle(curlm, slot->curl);
230 #endif
231 }
232
233 #ifdef USE_CURL_MULTI
234 static void process_curl_messages(void)
235 {
236         int num_messages;
237         struct active_request_slot *slot;
238         CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
239
240         while (curl_message != NULL) {
241                 if (curl_message->msg == CURLMSG_DONE) {
242                         int curl_result = curl_message->data.result;
243                         slot = active_queue_head;
244                         while (slot != NULL &&
245                                slot->curl != curl_message->easy_handle)
246                                 slot = slot->next;
247                         if (slot != NULL) {
248                                 xmulti_remove_handle(slot);
249                                 slot->curl_result = curl_result;
250                                 finish_active_slot(slot);
251                         } else {
252                                 fprintf(stderr, "Received DONE message for unknown request!\n");
253                         }
254                 } else {
255                         fprintf(stderr, "Unknown CURL message received: %d\n",
256                                 (int)curl_message->msg);
257                 }
258                 curl_message = curl_multi_info_read(curlm, &num_messages);
259         }
260 }
261 #endif
262
263 static int http_options(const char *var, const char *value, void *cb)
264 {
265         if (!strcmp("http.sslverify", var)) {
266                 curl_ssl_verify = git_config_bool(var, value);
267                 return 0;
268         }
269         if (!strcmp("http.sslcipherlist", var))
270                 return git_config_string(&ssl_cipherlist, var, value);
271         if (!strcmp("http.sslversion", var))
272                 return git_config_string(&ssl_version, var, value);
273         if (!strcmp("http.sslcert", var))
274                 return git_config_string(&ssl_cert, var, value);
275 #if LIBCURL_VERSION_NUM >= 0x070903
276         if (!strcmp("http.sslkey", var))
277                 return git_config_string(&ssl_key, var, value);
278 #endif
279 #if LIBCURL_VERSION_NUM >= 0x070908
280         if (!strcmp("http.sslcapath", var))
281                 return git_config_pathname(&ssl_capath, var, value);
282 #endif
283         if (!strcmp("http.sslcainfo", var))
284                 return git_config_pathname(&ssl_cainfo, var, value);
285         if (!strcmp("http.sslcertpasswordprotected", var)) {
286                 ssl_cert_password_required = git_config_bool(var, value);
287                 return 0;
288         }
289         if (!strcmp("http.ssltry", var)) {
290                 curl_ssl_try = git_config_bool(var, value);
291                 return 0;
292         }
293         if (!strcmp("http.minsessions", var)) {
294                 min_curl_sessions = git_config_int(var, value);
295 #ifndef USE_CURL_MULTI
296                 if (min_curl_sessions > 1)
297                         min_curl_sessions = 1;
298 #endif
299                 return 0;
300         }
301 #ifdef USE_CURL_MULTI
302         if (!strcmp("http.maxrequests", var)) {
303                 max_requests = git_config_int(var, value);
304                 return 0;
305         }
306 #endif
307         if (!strcmp("http.lowspeedlimit", var)) {
308                 curl_low_speed_limit = (long)git_config_int(var, value);
309                 return 0;
310         }
311         if (!strcmp("http.lowspeedtime", var)) {
312                 curl_low_speed_time = (long)git_config_int(var, value);
313                 return 0;
314         }
315
316         if (!strcmp("http.noepsv", var)) {
317                 curl_ftp_no_epsv = git_config_bool(var, value);
318                 return 0;
319         }
320         if (!strcmp("http.proxy", var))
321                 return git_config_string(&curl_http_proxy, var, value);
322
323         if (!strcmp("http.proxyauthmethod", var))
324                 return git_config_string(&http_proxy_authmethod, var, value);
325
326         if (!strcmp("http.cookiefile", var))
327                 return git_config_pathname(&curl_cookie_file, var, value);
328         if (!strcmp("http.savecookies", var)) {
329                 curl_save_cookies = git_config_bool(var, value);
330                 return 0;
331         }
332
333         if (!strcmp("http.postbuffer", var)) {
334                 http_post_buffer = git_config_ssize_t(var, value);
335                 if (http_post_buffer < 0)
336                         warning(_("negative value for http.postbuffer; defaulting to %d"), LARGE_PACKET_MAX);
337                 if (http_post_buffer < LARGE_PACKET_MAX)
338                         http_post_buffer = LARGE_PACKET_MAX;
339                 return 0;
340         }
341
342         if (!strcmp("http.useragent", var))
343                 return git_config_string(&user_agent, var, value);
344
345         if (!strcmp("http.emptyauth", var)) {
346                 if (value && !strcmp("auto", value))
347                         curl_empty_auth = -1;
348                 else
349                         curl_empty_auth = git_config_bool(var, value);
350                 return 0;
351         }
352
353         if (!strcmp("http.delegation", var)) {
354 #if LIBCURL_VERSION_NUM >= 0x071600
355                 return git_config_string(&curl_deleg, var, value);
356 #else
357                 warning(_("Delegation control is not supported with cURL < 7.22.0"));
358                 return 0;
359 #endif
360         }
361
362         if (!strcmp("http.pinnedpubkey", var)) {
363 #if LIBCURL_VERSION_NUM >= 0x072c00
364                 return git_config_pathname(&ssl_pinnedkey, var, value);
365 #else
366                 warning(_("Public key pinning not supported with cURL < 7.44.0"));
367                 return 0;
368 #endif
369         }
370
371         if (!strcmp("http.extraheader", var)) {
372                 if (!value) {
373                         return config_error_nonbool(var);
374                 } else if (!*value) {
375                         curl_slist_free_all(extra_http_headers);
376                         extra_http_headers = NULL;
377                 } else {
378                         extra_http_headers =
379                                 curl_slist_append(extra_http_headers, value);
380                 }
381                 return 0;
382         }
383
384         if (!strcmp("http.followredirects", var)) {
385                 if (value && !strcmp(value, "initial"))
386                         http_follow_config = HTTP_FOLLOW_INITIAL;
387                 else if (git_config_bool(var, value))
388                         http_follow_config = HTTP_FOLLOW_ALWAYS;
389                 else
390                         http_follow_config = HTTP_FOLLOW_NONE;
391                 return 0;
392         }
393
394         /* Fall back on the default ones */
395         return git_default_config(var, value, cb);
396 }
397
398 static int curl_empty_auth_enabled(void)
399 {
400         if (curl_empty_auth >= 0)
401                 return curl_empty_auth;
402
403 #ifndef LIBCURL_CAN_HANDLE_AUTH_ANY
404         /*
405          * Our libcurl is too old to do AUTH_ANY in the first place;
406          * just default to turning the feature off.
407          */
408 #else
409         /*
410          * In the automatic case, kick in the empty-auth
411          * hack as long as we would potentially try some
412          * method more exotic than "Basic" or "Digest".
413          *
414          * But only do this when this is our second or
415          * subsequent request, as by then we know what
416          * methods are available.
417          */
418         if (http_auth_methods_restricted &&
419             (http_auth_methods & ~empty_auth_useless))
420                 return 1;
421 #endif
422         return 0;
423 }
424
425 static void init_curl_http_auth(CURL *result)
426 {
427         if (!http_auth.username || !*http_auth.username) {
428                 if (curl_empty_auth_enabled())
429                         curl_easy_setopt(result, CURLOPT_USERPWD, ":");
430                 return;
431         }
432
433         credential_fill(&http_auth);
434
435 #if LIBCURL_VERSION_NUM >= 0x071301
436         curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
437         curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
438 #else
439         {
440                 static struct strbuf up = STRBUF_INIT;
441                 /*
442                  * Note that we assume we only ever have a single set of
443                  * credentials in a given program run, so we do not have
444                  * to worry about updating this buffer, only setting its
445                  * initial value.
446                  */
447                 if (!up.len)
448                         strbuf_addf(&up, "%s:%s",
449                                 http_auth.username, http_auth.password);
450                 curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
451         }
452 #endif
453 }
454
455 /* *var must be free-able */
456 static void var_override(const char **var, char *value)
457 {
458         if (value) {
459                 free((void *)*var);
460                 *var = xstrdup(value);
461         }
462 }
463
464 static void set_proxyauth_name_password(CURL *result)
465 {
466 #if LIBCURL_VERSION_NUM >= 0x071301
467                 curl_easy_setopt(result, CURLOPT_PROXYUSERNAME,
468                         proxy_auth.username);
469                 curl_easy_setopt(result, CURLOPT_PROXYPASSWORD,
470                         proxy_auth.password);
471 #else
472                 struct strbuf s = STRBUF_INIT;
473
474                 strbuf_addstr_urlencode(&s, proxy_auth.username, 1);
475                 strbuf_addch(&s, ':');
476                 strbuf_addstr_urlencode(&s, proxy_auth.password, 1);
477                 curl_proxyuserpwd = strbuf_detach(&s, NULL);
478                 curl_easy_setopt(result, CURLOPT_PROXYUSERPWD, curl_proxyuserpwd);
479 #endif
480 }
481
482 static void init_curl_proxy_auth(CURL *result)
483 {
484         if (proxy_auth.username) {
485                 if (!proxy_auth.password)
486                         credential_fill(&proxy_auth);
487                 set_proxyauth_name_password(result);
488         }
489
490         var_override(&http_proxy_authmethod, getenv("GIT_HTTP_PROXY_AUTHMETHOD"));
491
492 #if LIBCURL_VERSION_NUM >= 0x070a07 /* CURLOPT_PROXYAUTH and CURLAUTH_ANY */
493         if (http_proxy_authmethod) {
494                 int i;
495                 for (i = 0; i < ARRAY_SIZE(proxy_authmethods); i++) {
496                         if (!strcmp(http_proxy_authmethod, proxy_authmethods[i].name)) {
497                                 curl_easy_setopt(result, CURLOPT_PROXYAUTH,
498                                                 proxy_authmethods[i].curlauth_param);
499                                 break;
500                         }
501                 }
502                 if (i == ARRAY_SIZE(proxy_authmethods)) {
503                         warning("unsupported proxy authentication method %s: using anyauth",
504                                         http_proxy_authmethod);
505                         curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
506                 }
507         }
508         else
509                 curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
510 #endif
511 }
512
513 static int has_cert_password(void)
514 {
515         if (ssl_cert == NULL || ssl_cert_password_required != 1)
516                 return 0;
517         if (!cert_auth.password) {
518                 cert_auth.protocol = xstrdup("cert");
519                 cert_auth.username = xstrdup("");
520                 cert_auth.path = xstrdup(ssl_cert);
521                 credential_fill(&cert_auth);
522         }
523         return 1;
524 }
525
526 #if LIBCURL_VERSION_NUM >= 0x071900
527 static void set_curl_keepalive(CURL *c)
528 {
529         curl_easy_setopt(c, CURLOPT_TCP_KEEPALIVE, 1);
530 }
531
532 #elif LIBCURL_VERSION_NUM >= 0x071000
533 static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
534 {
535         int ka = 1;
536         int rc;
537         socklen_t len = (socklen_t)sizeof(ka);
538
539         if (type != CURLSOCKTYPE_IPCXN)
540                 return 0;
541
542         rc = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&ka, len);
543         if (rc < 0)
544                 warning_errno("unable to set SO_KEEPALIVE on socket");
545
546         return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
547 }
548
549 static void set_curl_keepalive(CURL *c)
550 {
551         curl_easy_setopt(c, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
552 }
553
554 #else
555 static void set_curl_keepalive(CURL *c)
556 {
557         /* not supported on older curl versions */
558 }
559 #endif
560
561 static void redact_sensitive_header(struct strbuf *header)
562 {
563         const char *sensitive_header;
564
565         if (skip_prefix(header->buf, "Authorization:", &sensitive_header) ||
566             skip_prefix(header->buf, "Proxy-Authorization:", &sensitive_header)) {
567                 /* The first token is the type, which is OK to log */
568                 while (isspace(*sensitive_header))
569                         sensitive_header++;
570                 while (*sensitive_header && !isspace(*sensitive_header))
571                         sensitive_header++;
572                 /* Everything else is opaque and possibly sensitive */
573                 strbuf_setlen(header,  sensitive_header - header->buf);
574                 strbuf_addstr(header, " <redacted>");
575         }
576 }
577
578 static void curl_dump_header(const char *text, unsigned char *ptr, size_t size, int hide_sensitive_header)
579 {
580         struct strbuf out = STRBUF_INIT;
581         struct strbuf **headers, **header;
582
583         strbuf_addf(&out, "%s, %10.10ld bytes (0x%8.8lx)\n",
584                 text, (long)size, (long)size);
585         trace_strbuf(&trace_curl, &out);
586         strbuf_reset(&out);
587         strbuf_add(&out, ptr, size);
588         headers = strbuf_split_max(&out, '\n', 0);
589
590         for (header = headers; *header; header++) {
591                 if (hide_sensitive_header)
592                         redact_sensitive_header(*header);
593                 strbuf_insert((*header), 0, text, strlen(text));
594                 strbuf_insert((*header), strlen(text), ": ", 2);
595                 strbuf_rtrim((*header));
596                 strbuf_addch((*header), '\n');
597                 trace_strbuf(&trace_curl, (*header));
598         }
599         strbuf_list_free(headers);
600         strbuf_release(&out);
601 }
602
603 static void curl_dump_data(const char *text, unsigned char *ptr, size_t size)
604 {
605         size_t i;
606         struct strbuf out = STRBUF_INIT;
607         unsigned int width = 60;
608
609         strbuf_addf(&out, "%s, %10.10ld bytes (0x%8.8lx)\n",
610                 text, (long)size, (long)size);
611         trace_strbuf(&trace_curl, &out);
612
613         for (i = 0; i < size; i += width) {
614                 size_t w;
615
616                 strbuf_reset(&out);
617                 strbuf_addf(&out, "%s: ", text);
618                 for (w = 0; (w < width) && (i + w < size); w++) {
619                         unsigned char ch = ptr[i + w];
620
621                         strbuf_addch(&out,
622                                        (ch >= 0x20) && (ch < 0x80)
623                                        ? ch : '.');
624                 }
625                 strbuf_addch(&out, '\n');
626                 trace_strbuf(&trace_curl, &out);
627         }
628         strbuf_release(&out);
629 }
630
631 static int curl_trace(CURL *handle, curl_infotype type, char *data, size_t size, void *userp)
632 {
633         const char *text;
634         enum { NO_FILTER = 0, DO_FILTER = 1 };
635
636         switch (type) {
637         case CURLINFO_TEXT:
638                 trace_printf_key(&trace_curl, "== Info: %s", data);
639         default:                /* we ignore unknown types by default */
640                 return 0;
641
642         case CURLINFO_HEADER_OUT:
643                 text = "=> Send header";
644                 curl_dump_header(text, (unsigned char *)data, size, DO_FILTER);
645                 break;
646         case CURLINFO_DATA_OUT:
647                 text = "=> Send data";
648                 curl_dump_data(text, (unsigned char *)data, size);
649                 break;
650         case CURLINFO_SSL_DATA_OUT:
651                 text = "=> Send SSL data";
652                 curl_dump_data(text, (unsigned char *)data, size);
653                 break;
654         case CURLINFO_HEADER_IN:
655                 text = "<= Recv header";
656                 curl_dump_header(text, (unsigned char *)data, size, NO_FILTER);
657                 break;
658         case CURLINFO_DATA_IN:
659                 text = "<= Recv data";
660                 curl_dump_data(text, (unsigned char *)data, size);
661                 break;
662         case CURLINFO_SSL_DATA_IN:
663                 text = "<= Recv SSL data";
664                 curl_dump_data(text, (unsigned char *)data, size);
665                 break;
666         }
667         return 0;
668 }
669
670 void setup_curl_trace(CURL *handle)
671 {
672         if (!trace_want(&trace_curl))
673                 return;
674         curl_easy_setopt(handle, CURLOPT_VERBOSE, 1L);
675         curl_easy_setopt(handle, CURLOPT_DEBUGFUNCTION, curl_trace);
676         curl_easy_setopt(handle, CURLOPT_DEBUGDATA, NULL);
677 }
678
679 static long get_curl_allowed_protocols(int from_user)
680 {
681         long allowed_protocols = 0;
682
683         if (is_transport_allowed("http", from_user))
684                 allowed_protocols |= CURLPROTO_HTTP;
685         if (is_transport_allowed("https", from_user))
686                 allowed_protocols |= CURLPROTO_HTTPS;
687         if (is_transport_allowed("ftp", from_user))
688                 allowed_protocols |= CURLPROTO_FTP;
689         if (is_transport_allowed("ftps", from_user))
690                 allowed_protocols |= CURLPROTO_FTPS;
691
692         return allowed_protocols;
693 }
694
695 static CURL *get_curl_handle(void)
696 {
697         CURL *result = curl_easy_init();
698
699         if (!result)
700                 die("curl_easy_init failed");
701
702         if (!curl_ssl_verify) {
703                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
704                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
705         } else {
706                 /* Verify authenticity of the peer's certificate */
707                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
708                 /* The name in the cert must match whom we tried to connect */
709                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
710         }
711
712 #if LIBCURL_VERSION_NUM >= 0x070907
713         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
714 #endif
715 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
716         curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
717 #endif
718
719 #if LIBCURL_VERSION_NUM >= 0x071600
720         if (curl_deleg) {
721                 int i;
722                 for (i = 0; i < ARRAY_SIZE(curl_deleg_levels); i++) {
723                         if (!strcmp(curl_deleg, curl_deleg_levels[i].name)) {
724                                 curl_easy_setopt(result, CURLOPT_GSSAPI_DELEGATION,
725                                                 curl_deleg_levels[i].curl_deleg_param);
726                                 break;
727                         }
728                 }
729                 if (i == ARRAY_SIZE(curl_deleg_levels))
730                         warning("Unknown delegation method '%s': using default",
731                                 curl_deleg);
732         }
733 #endif
734
735         if (http_proactive_auth)
736                 init_curl_http_auth(result);
737
738         if (getenv("GIT_SSL_VERSION"))
739                 ssl_version = getenv("GIT_SSL_VERSION");
740         if (ssl_version && *ssl_version) {
741                 int i;
742                 for (i = 0; i < ARRAY_SIZE(sslversions); i++) {
743                         if (!strcmp(ssl_version, sslversions[i].name)) {
744                                 curl_easy_setopt(result, CURLOPT_SSLVERSION,
745                                                  sslversions[i].ssl_version);
746                                 break;
747                         }
748                 }
749                 if (i == ARRAY_SIZE(sslversions))
750                         warning("unsupported ssl version %s: using default",
751                                 ssl_version);
752         }
753
754         if (getenv("GIT_SSL_CIPHER_LIST"))
755                 ssl_cipherlist = getenv("GIT_SSL_CIPHER_LIST");
756         if (ssl_cipherlist != NULL && *ssl_cipherlist)
757                 curl_easy_setopt(result, CURLOPT_SSL_CIPHER_LIST,
758                                 ssl_cipherlist);
759
760         if (ssl_cert != NULL)
761                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
762         if (has_cert_password())
763                 curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
764 #if LIBCURL_VERSION_NUM >= 0x070903
765         if (ssl_key != NULL)
766                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
767 #endif
768 #if LIBCURL_VERSION_NUM >= 0x070908
769         if (ssl_capath != NULL)
770                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
771 #endif
772 #if LIBCURL_VERSION_NUM >= 0x072c00
773         if (ssl_pinnedkey != NULL)
774                 curl_easy_setopt(result, CURLOPT_PINNEDPUBLICKEY, ssl_pinnedkey);
775 #endif
776         if (ssl_cainfo != NULL)
777                 curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
778
779         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
780                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
781                                  curl_low_speed_limit);
782                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
783                                  curl_low_speed_time);
784         }
785
786         curl_easy_setopt(result, CURLOPT_MAXREDIRS, 20);
787 #if LIBCURL_VERSION_NUM >= 0x071301
788         curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
789 #elif LIBCURL_VERSION_NUM >= 0x071101
790         curl_easy_setopt(result, CURLOPT_POST301, 1);
791 #endif
792 #if LIBCURL_VERSION_NUM >= 0x071304
793         curl_easy_setopt(result, CURLOPT_REDIR_PROTOCOLS,
794                          get_curl_allowed_protocols(0));
795         curl_easy_setopt(result, CURLOPT_PROTOCOLS,
796                          get_curl_allowed_protocols(-1));
797 #else
798         warning("protocol restrictions not applied to curl redirects because\n"
799                 "your curl version is too old (>= 7.19.4)");
800 #endif
801         if (getenv("GIT_CURL_VERBOSE"))
802                 curl_easy_setopt(result, CURLOPT_VERBOSE, 1L);
803         setup_curl_trace(result);
804
805         curl_easy_setopt(result, CURLOPT_USERAGENT,
806                 user_agent ? user_agent : git_user_agent());
807
808         if (curl_ftp_no_epsv)
809                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
810
811 #ifdef CURLOPT_USE_SSL
812         if (curl_ssl_try)
813                 curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
814 #endif
815
816         /*
817          * CURL also examines these variables as a fallback; but we need to query
818          * them here in order to decide whether to prompt for missing password (cf.
819          * init_curl_proxy_auth()).
820          *
821          * Unlike many other common environment variables, these are historically
822          * lowercase only. It appears that CURL did not know this and implemented
823          * only uppercase variants, which was later corrected to take both - with
824          * the exception of http_proxy, which is lowercase only also in CURL. As
825          * the lowercase versions are the historical quasi-standard, they take
826          * precedence here, as in CURL.
827          */
828         if (!curl_http_proxy) {
829                 if (http_auth.protocol && !strcmp(http_auth.protocol, "https")) {
830                         var_override(&curl_http_proxy, getenv("HTTPS_PROXY"));
831                         var_override(&curl_http_proxy, getenv("https_proxy"));
832                 } else {
833                         var_override(&curl_http_proxy, getenv("http_proxy"));
834                 }
835                 if (!curl_http_proxy) {
836                         var_override(&curl_http_proxy, getenv("ALL_PROXY"));
837                         var_override(&curl_http_proxy, getenv("all_proxy"));
838                 }
839         }
840
841         if (curl_http_proxy) {
842                 curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
843 #if LIBCURL_VERSION_NUM >= 0x071800
844                 if (starts_with(curl_http_proxy, "socks5h"))
845                         curl_easy_setopt(result,
846                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5_HOSTNAME);
847                 else if (starts_with(curl_http_proxy, "socks5"))
848                         curl_easy_setopt(result,
849                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5);
850                 else if (starts_with(curl_http_proxy, "socks4a"))
851                         curl_easy_setopt(result,
852                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4A);
853                 else if (starts_with(curl_http_proxy, "socks"))
854                         curl_easy_setopt(result,
855                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4);
856 #endif
857                 if (strstr(curl_http_proxy, "://"))
858                         credential_from_url(&proxy_auth, curl_http_proxy);
859                 else {
860                         struct strbuf url = STRBUF_INIT;
861                         strbuf_addf(&url, "http://%s", curl_http_proxy);
862                         credential_from_url(&proxy_auth, url.buf);
863                         strbuf_release(&url);
864                 }
865
866                 curl_easy_setopt(result, CURLOPT_PROXY, proxy_auth.host);
867 #if LIBCURL_VERSION_NUM >= 0x071304
868                 var_override(&curl_no_proxy, getenv("NO_PROXY"));
869                 var_override(&curl_no_proxy, getenv("no_proxy"));
870                 curl_easy_setopt(result, CURLOPT_NOPROXY, curl_no_proxy);
871 #endif
872         }
873         init_curl_proxy_auth(result);
874
875         set_curl_keepalive(result);
876
877         return result;
878 }
879
880 static void set_from_env(const char **var, const char *envname)
881 {
882         const char *val = getenv(envname);
883         if (val)
884                 *var = val;
885 }
886
887 void http_init(struct remote *remote, const char *url, int proactive_auth)
888 {
889         char *low_speed_limit;
890         char *low_speed_time;
891         char *normalized_url;
892         struct urlmatch_config config = { STRING_LIST_INIT_DUP };
893
894         config.section = "http";
895         config.key = NULL;
896         config.collect_fn = http_options;
897         config.cascade_fn = git_default_config;
898         config.cb = NULL;
899
900         http_is_verbose = 0;
901         normalized_url = url_normalize(url, &config.url);
902
903         git_config(urlmatch_config_entry, &config);
904         free(normalized_url);
905
906         if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK)
907                 die("curl_global_init failed");
908
909         http_proactive_auth = proactive_auth;
910
911         if (remote && remote->http_proxy)
912                 curl_http_proxy = xstrdup(remote->http_proxy);
913
914         if (remote)
915                 var_override(&http_proxy_authmethod, remote->http_proxy_authmethod);
916
917         pragma_header = curl_slist_append(http_copy_default_headers(),
918                 "Pragma: no-cache");
919         no_pragma_header = curl_slist_append(http_copy_default_headers(),
920                 "Pragma:");
921
922 #ifdef USE_CURL_MULTI
923         {
924                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
925                 if (http_max_requests != NULL)
926                         max_requests = atoi(http_max_requests);
927         }
928
929         curlm = curl_multi_init();
930         if (!curlm)
931                 die("curl_multi_init failed");
932 #endif
933
934         if (getenv("GIT_SSL_NO_VERIFY"))
935                 curl_ssl_verify = 0;
936
937         set_from_env(&ssl_cert, "GIT_SSL_CERT");
938 #if LIBCURL_VERSION_NUM >= 0x070903
939         set_from_env(&ssl_key, "GIT_SSL_KEY");
940 #endif
941 #if LIBCURL_VERSION_NUM >= 0x070908
942         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
943 #endif
944         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
945
946         set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
947
948         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
949         if (low_speed_limit != NULL)
950                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
951         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
952         if (low_speed_time != NULL)
953                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
954
955         if (curl_ssl_verify == -1)
956                 curl_ssl_verify = 1;
957
958         curl_session_count = 0;
959 #ifdef USE_CURL_MULTI
960         if (max_requests < 1)
961                 max_requests = DEFAULT_MAX_REQUESTS;
962 #endif
963
964         if (getenv("GIT_CURL_FTP_NO_EPSV"))
965                 curl_ftp_no_epsv = 1;
966
967         if (url) {
968                 credential_from_url(&http_auth, url);
969                 if (!ssl_cert_password_required &&
970                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
971                     starts_with(url, "https://"))
972                         ssl_cert_password_required = 1;
973         }
974
975 #ifndef NO_CURL_EASY_DUPHANDLE
976         curl_default = get_curl_handle();
977 #endif
978 }
979
980 void http_cleanup(void)
981 {
982         struct active_request_slot *slot = active_queue_head;
983
984         while (slot != NULL) {
985                 struct active_request_slot *next = slot->next;
986                 if (slot->curl != NULL) {
987                         xmulti_remove_handle(slot);
988                         curl_easy_cleanup(slot->curl);
989                 }
990                 free(slot);
991                 slot = next;
992         }
993         active_queue_head = NULL;
994
995 #ifndef NO_CURL_EASY_DUPHANDLE
996         curl_easy_cleanup(curl_default);
997 #endif
998
999 #ifdef USE_CURL_MULTI
1000         curl_multi_cleanup(curlm);
1001 #endif
1002         curl_global_cleanup();
1003
1004         curl_slist_free_all(extra_http_headers);
1005         extra_http_headers = NULL;
1006
1007         curl_slist_free_all(pragma_header);
1008         pragma_header = NULL;
1009
1010         curl_slist_free_all(no_pragma_header);
1011         no_pragma_header = NULL;
1012
1013         if (curl_http_proxy) {
1014                 free((void *)curl_http_proxy);
1015                 curl_http_proxy = NULL;
1016         }
1017
1018         if (proxy_auth.password) {
1019                 memset(proxy_auth.password, 0, strlen(proxy_auth.password));
1020                 free(proxy_auth.password);
1021                 proxy_auth.password = NULL;
1022         }
1023
1024         free((void *)curl_proxyuserpwd);
1025         curl_proxyuserpwd = NULL;
1026
1027         free((void *)http_proxy_authmethod);
1028         http_proxy_authmethod = NULL;
1029
1030         if (cert_auth.password != NULL) {
1031                 memset(cert_auth.password, 0, strlen(cert_auth.password));
1032                 free(cert_auth.password);
1033                 cert_auth.password = NULL;
1034         }
1035         ssl_cert_password_required = 0;
1036
1037         free(cached_accept_language);
1038         cached_accept_language = NULL;
1039 }
1040
1041 struct active_request_slot *get_active_slot(void)
1042 {
1043         struct active_request_slot *slot = active_queue_head;
1044         struct active_request_slot *newslot;
1045
1046 #ifdef USE_CURL_MULTI
1047         int num_transfers;
1048
1049         /* Wait for a slot to open up if the queue is full */
1050         while (active_requests >= max_requests) {
1051                 curl_multi_perform(curlm, &num_transfers);
1052                 if (num_transfers < active_requests)
1053                         process_curl_messages();
1054         }
1055 #endif
1056
1057         while (slot != NULL && slot->in_use)
1058                 slot = slot->next;
1059
1060         if (slot == NULL) {
1061                 newslot = xmalloc(sizeof(*newslot));
1062                 newslot->curl = NULL;
1063                 newslot->in_use = 0;
1064                 newslot->next = NULL;
1065
1066                 slot = active_queue_head;
1067                 if (slot == NULL) {
1068                         active_queue_head = newslot;
1069                 } else {
1070                         while (slot->next != NULL)
1071                                 slot = slot->next;
1072                         slot->next = newslot;
1073                 }
1074                 slot = newslot;
1075         }
1076
1077         if (slot->curl == NULL) {
1078 #ifdef NO_CURL_EASY_DUPHANDLE
1079                 slot->curl = get_curl_handle();
1080 #else
1081                 slot->curl = curl_easy_duphandle(curl_default);
1082 #endif
1083                 curl_session_count++;
1084         }
1085
1086         active_requests++;
1087         slot->in_use = 1;
1088         slot->results = NULL;
1089         slot->finished = NULL;
1090         slot->callback_data = NULL;
1091         slot->callback_func = NULL;
1092         curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
1093         if (curl_save_cookies)
1094                 curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
1095         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
1096         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
1097         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
1098         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
1099         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
1100         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
1101         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
1102         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1103         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
1104         curl_easy_setopt(slot->curl, CURLOPT_RANGE, NULL);
1105
1106         /*
1107          * Default following to off unless "ALWAYS" is configured; this gives
1108          * callers a sane starting point, and they can tweak for individual
1109          * HTTP_FOLLOW_* cases themselves.
1110          */
1111         if (http_follow_config == HTTP_FOLLOW_ALWAYS)
1112                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 1);
1113         else
1114                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 0);
1115
1116 #if LIBCURL_VERSION_NUM >= 0x070a08
1117         curl_easy_setopt(slot->curl, CURLOPT_IPRESOLVE, git_curl_ipresolve);
1118 #endif
1119 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
1120         curl_easy_setopt(slot->curl, CURLOPT_HTTPAUTH, http_auth_methods);
1121 #endif
1122         if (http_auth.password || curl_empty_auth_enabled())
1123                 init_curl_http_auth(slot->curl);
1124
1125         return slot;
1126 }
1127
1128 int start_active_slot(struct active_request_slot *slot)
1129 {
1130 #ifdef USE_CURL_MULTI
1131         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
1132         int num_transfers;
1133
1134         if (curlm_result != CURLM_OK &&
1135             curlm_result != CURLM_CALL_MULTI_PERFORM) {
1136                 warning("curl_multi_add_handle failed: %s",
1137                         curl_multi_strerror(curlm_result));
1138                 active_requests--;
1139                 slot->in_use = 0;
1140                 return 0;
1141         }
1142
1143         /*
1144          * We know there must be something to do, since we just added
1145          * something.
1146          */
1147         curl_multi_perform(curlm, &num_transfers);
1148 #endif
1149         return 1;
1150 }
1151
1152 #ifdef USE_CURL_MULTI
1153 struct fill_chain {
1154         void *data;
1155         int (*fill)(void *);
1156         struct fill_chain *next;
1157 };
1158
1159 static struct fill_chain *fill_cfg;
1160
1161 void add_fill_function(void *data, int (*fill)(void *))
1162 {
1163         struct fill_chain *new = xmalloc(sizeof(*new));
1164         struct fill_chain **linkp = &fill_cfg;
1165         new->data = data;
1166         new->fill = fill;
1167         new->next = NULL;
1168         while (*linkp)
1169                 linkp = &(*linkp)->next;
1170         *linkp = new;
1171 }
1172
1173 void fill_active_slots(void)
1174 {
1175         struct active_request_slot *slot = active_queue_head;
1176
1177         while (active_requests < max_requests) {
1178                 struct fill_chain *fill;
1179                 for (fill = fill_cfg; fill; fill = fill->next)
1180                         if (fill->fill(fill->data))
1181                                 break;
1182
1183                 if (!fill)
1184                         break;
1185         }
1186
1187         while (slot != NULL) {
1188                 if (!slot->in_use && slot->curl != NULL
1189                         && curl_session_count > min_curl_sessions) {
1190                         curl_easy_cleanup(slot->curl);
1191                         slot->curl = NULL;
1192                         curl_session_count--;
1193                 }
1194                 slot = slot->next;
1195         }
1196 }
1197
1198 void step_active_slots(void)
1199 {
1200         int num_transfers;
1201         CURLMcode curlm_result;
1202
1203         do {
1204                 curlm_result = curl_multi_perform(curlm, &num_transfers);
1205         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
1206         if (num_transfers < active_requests) {
1207                 process_curl_messages();
1208                 fill_active_slots();
1209         }
1210 }
1211 #endif
1212
1213 void run_active_slot(struct active_request_slot *slot)
1214 {
1215 #ifdef USE_CURL_MULTI
1216         fd_set readfds;
1217         fd_set writefds;
1218         fd_set excfds;
1219         int max_fd;
1220         struct timeval select_timeout;
1221         int finished = 0;
1222
1223         slot->finished = &finished;
1224         while (!finished) {
1225                 step_active_slots();
1226
1227                 if (slot->in_use) {
1228 #if LIBCURL_VERSION_NUM >= 0x070f04
1229                         long curl_timeout;
1230                         curl_multi_timeout(curlm, &curl_timeout);
1231                         if (curl_timeout == 0) {
1232                                 continue;
1233                         } else if (curl_timeout == -1) {
1234                                 select_timeout.tv_sec  = 0;
1235                                 select_timeout.tv_usec = 50000;
1236                         } else {
1237                                 select_timeout.tv_sec  =  curl_timeout / 1000;
1238                                 select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
1239                         }
1240 #else
1241                         select_timeout.tv_sec  = 0;
1242                         select_timeout.tv_usec = 50000;
1243 #endif
1244
1245                         max_fd = -1;
1246                         FD_ZERO(&readfds);
1247                         FD_ZERO(&writefds);
1248                         FD_ZERO(&excfds);
1249                         curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
1250
1251                         /*
1252                          * It can happen that curl_multi_timeout returns a pathologically
1253                          * long timeout when curl_multi_fdset returns no file descriptors
1254                          * to read.  See commit message for more details.
1255                          */
1256                         if (max_fd < 0 &&
1257                             (select_timeout.tv_sec > 0 ||
1258                              select_timeout.tv_usec > 50000)) {
1259                                 select_timeout.tv_sec  = 0;
1260                                 select_timeout.tv_usec = 50000;
1261                         }
1262
1263                         select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
1264                 }
1265         }
1266 #else
1267         while (slot->in_use) {
1268                 slot->curl_result = curl_easy_perform(slot->curl);
1269                 finish_active_slot(slot);
1270         }
1271 #endif
1272 }
1273
1274 static void release_active_slot(struct active_request_slot *slot)
1275 {
1276         closedown_active_slot(slot);
1277         if (slot->curl) {
1278                 xmulti_remove_handle(slot);
1279                 if (curl_session_count > min_curl_sessions) {
1280                         curl_easy_cleanup(slot->curl);
1281                         slot->curl = NULL;
1282                         curl_session_count--;
1283                 }
1284         }
1285 #ifdef USE_CURL_MULTI
1286         fill_active_slots();
1287 #endif
1288 }
1289
1290 void finish_all_active_slots(void)
1291 {
1292         struct active_request_slot *slot = active_queue_head;
1293
1294         while (slot != NULL)
1295                 if (slot->in_use) {
1296                         run_active_slot(slot);
1297                         slot = active_queue_head;
1298                 } else {
1299                         slot = slot->next;
1300                 }
1301 }
1302
1303 /* Helpers for modifying and creating URLs */
1304 static inline int needs_quote(int ch)
1305 {
1306         if (((ch >= 'A') && (ch <= 'Z'))
1307                         || ((ch >= 'a') && (ch <= 'z'))
1308                         || ((ch >= '0') && (ch <= '9'))
1309                         || (ch == '/')
1310                         || (ch == '-')
1311                         || (ch == '.'))
1312                 return 0;
1313         return 1;
1314 }
1315
1316 static char *quote_ref_url(const char *base, const char *ref)
1317 {
1318         struct strbuf buf = STRBUF_INIT;
1319         const char *cp;
1320         int ch;
1321
1322         end_url_with_slash(&buf, base);
1323
1324         for (cp = ref; (ch = *cp) != 0; cp++)
1325                 if (needs_quote(ch))
1326                         strbuf_addf(&buf, "%%%02x", ch);
1327                 else
1328                         strbuf_addch(&buf, *cp);
1329
1330         return strbuf_detach(&buf, NULL);
1331 }
1332
1333 void append_remote_object_url(struct strbuf *buf, const char *url,
1334                               const char *hex,
1335                               int only_two_digit_prefix)
1336 {
1337         end_url_with_slash(buf, url);
1338
1339         strbuf_addf(buf, "objects/%.*s/", 2, hex);
1340         if (!only_two_digit_prefix)
1341                 strbuf_addstr(buf, hex + 2);
1342 }
1343
1344 char *get_remote_object_url(const char *url, const char *hex,
1345                             int only_two_digit_prefix)
1346 {
1347         struct strbuf buf = STRBUF_INIT;
1348         append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
1349         return strbuf_detach(&buf, NULL);
1350 }
1351
1352 static int handle_curl_result(struct slot_results *results)
1353 {
1354         /*
1355          * If we see a failing http code with CURLE_OK, we have turned off
1356          * FAILONERROR (to keep the server's custom error response), and should
1357          * translate the code into failure here.
1358          *
1359          * Likewise, if we see a redirect (30x code), that means we turned off
1360          * redirect-following, and we should treat the result as an error.
1361          */
1362         if (results->curl_result == CURLE_OK &&
1363             results->http_code >= 300) {
1364                 results->curl_result = CURLE_HTTP_RETURNED_ERROR;
1365                 /*
1366                  * Normally curl will already have put the "reason phrase"
1367                  * from the server into curl_errorstr; unfortunately without
1368                  * FAILONERROR it is lost, so we can give only the numeric
1369                  * status code.
1370                  */
1371                 snprintf(curl_errorstr, sizeof(curl_errorstr),
1372                          "The requested URL returned error: %ld",
1373                          results->http_code);
1374         }
1375
1376         if (results->curl_result == CURLE_OK) {
1377                 credential_approve(&http_auth);
1378                 if (proxy_auth.password)
1379                         credential_approve(&proxy_auth);
1380                 return HTTP_OK;
1381         } else if (missing_target(results))
1382                 return HTTP_MISSING_TARGET;
1383         else if (results->http_code == 401) {
1384                 if (http_auth.username && http_auth.password) {
1385                         credential_reject(&http_auth);
1386                         return HTTP_NOAUTH;
1387                 } else {
1388 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
1389                         http_auth_methods &= ~CURLAUTH_GSSNEGOTIATE;
1390                         if (results->auth_avail) {
1391                                 http_auth_methods &= results->auth_avail;
1392                                 http_auth_methods_restricted = 1;
1393                         }
1394 #endif
1395                         return HTTP_REAUTH;
1396                 }
1397         } else {
1398                 if (results->http_connectcode == 407)
1399                         credential_reject(&proxy_auth);
1400 #if LIBCURL_VERSION_NUM >= 0x070c00
1401                 if (!curl_errorstr[0])
1402                         strlcpy(curl_errorstr,
1403                                 curl_easy_strerror(results->curl_result),
1404                                 sizeof(curl_errorstr));
1405 #endif
1406                 return HTTP_ERROR;
1407         }
1408 }
1409
1410 int run_one_slot(struct active_request_slot *slot,
1411                  struct slot_results *results)
1412 {
1413         slot->results = results;
1414         if (!start_active_slot(slot)) {
1415                 snprintf(curl_errorstr, sizeof(curl_errorstr),
1416                          "failed to start HTTP request");
1417                 return HTTP_START_FAILED;
1418         }
1419
1420         run_active_slot(slot);
1421         return handle_curl_result(results);
1422 }
1423
1424 struct curl_slist *http_copy_default_headers(void)
1425 {
1426         struct curl_slist *headers = NULL, *h;
1427
1428         for (h = extra_http_headers; h; h = h->next)
1429                 headers = curl_slist_append(headers, h->data);
1430
1431         return headers;
1432 }
1433
1434 static CURLcode curlinfo_strbuf(CURL *curl, CURLINFO info, struct strbuf *buf)
1435 {
1436         char *ptr;
1437         CURLcode ret;
1438
1439         strbuf_reset(buf);
1440         ret = curl_easy_getinfo(curl, info, &ptr);
1441         if (!ret && ptr)
1442                 strbuf_addstr(buf, ptr);
1443         return ret;
1444 }
1445
1446 /*
1447  * Check for and extract a content-type parameter. "raw"
1448  * should be positioned at the start of the potential
1449  * parameter, with any whitespace already removed.
1450  *
1451  * "name" is the name of the parameter. The value is appended
1452  * to "out".
1453  */
1454 static int extract_param(const char *raw, const char *name,
1455                          struct strbuf *out)
1456 {
1457         size_t len = strlen(name);
1458
1459         if (strncasecmp(raw, name, len))
1460                 return -1;
1461         raw += len;
1462
1463         if (*raw != '=')
1464                 return -1;
1465         raw++;
1466
1467         while (*raw && !isspace(*raw) && *raw != ';')
1468                 strbuf_addch(out, *raw++);
1469         return 0;
1470 }
1471
1472 /*
1473  * Extract a normalized version of the content type, with any
1474  * spaces suppressed, all letters lowercased, and no trailing ";"
1475  * or parameters.
1476  *
1477  * Note that we will silently remove even invalid whitespace. For
1478  * example, "text / plain" is specifically forbidden by RFC 2616,
1479  * but "text/plain" is the only reasonable output, and this keeps
1480  * our code simple.
1481  *
1482  * If the "charset" argument is not NULL, store the value of any
1483  * charset parameter there.
1484  *
1485  * Example:
1486  *   "TEXT/PLAIN; charset=utf-8" -> "text/plain", "utf-8"
1487  *   "text / plain" -> "text/plain"
1488  */
1489 static void extract_content_type(struct strbuf *raw, struct strbuf *type,
1490                                  struct strbuf *charset)
1491 {
1492         const char *p;
1493
1494         strbuf_reset(type);
1495         strbuf_grow(type, raw->len);
1496         for (p = raw->buf; *p; p++) {
1497                 if (isspace(*p))
1498                         continue;
1499                 if (*p == ';') {
1500                         p++;
1501                         break;
1502                 }
1503                 strbuf_addch(type, tolower(*p));
1504         }
1505
1506         if (!charset)
1507                 return;
1508
1509         strbuf_reset(charset);
1510         while (*p) {
1511                 while (isspace(*p) || *p == ';')
1512                         p++;
1513                 if (!extract_param(p, "charset", charset))
1514                         return;
1515                 while (*p && !isspace(*p))
1516                         p++;
1517         }
1518
1519         if (!charset->len && starts_with(type->buf, "text/"))
1520                 strbuf_addstr(charset, "ISO-8859-1");
1521 }
1522
1523 static void write_accept_language(struct strbuf *buf)
1524 {
1525         /*
1526          * MAX_DECIMAL_PLACES must not be larger than 3. If it is larger than
1527          * that, q-value will be smaller than 0.001, the minimum q-value the
1528          * HTTP specification allows. See
1529          * http://tools.ietf.org/html/rfc7231#section-5.3.1 for q-value.
1530          */
1531         const int MAX_DECIMAL_PLACES = 3;
1532         const int MAX_LANGUAGE_TAGS = 1000;
1533         const int MAX_ACCEPT_LANGUAGE_HEADER_SIZE = 4000;
1534         char **language_tags = NULL;
1535         int num_langs = 0;
1536         const char *s = get_preferred_languages();
1537         int i;
1538         struct strbuf tag = STRBUF_INIT;
1539
1540         /* Don't add Accept-Language header if no language is preferred. */
1541         if (!s)
1542                 return;
1543
1544         /*
1545          * Split the colon-separated string of preferred languages into
1546          * language_tags array.
1547          */
1548         do {
1549                 /* collect language tag */
1550                 for (; *s && (isalnum(*s) || *s == '_'); s++)
1551                         strbuf_addch(&tag, *s == '_' ? '-' : *s);
1552
1553                 /* skip .codeset, @modifier and any other unnecessary parts */
1554                 while (*s && *s != ':')
1555                         s++;
1556
1557                 if (tag.len) {
1558                         num_langs++;
1559                         REALLOC_ARRAY(language_tags, num_langs);
1560                         language_tags[num_langs - 1] = strbuf_detach(&tag, NULL);
1561                         if (num_langs >= MAX_LANGUAGE_TAGS - 1) /* -1 for '*' */
1562                                 break;
1563                 }
1564         } while (*s++);
1565
1566         /* write Accept-Language header into buf */
1567         if (num_langs) {
1568                 int last_buf_len = 0;
1569                 int max_q;
1570                 int decimal_places;
1571                 char q_format[32];
1572
1573                 /* add '*' */
1574                 REALLOC_ARRAY(language_tags, num_langs + 1);
1575                 language_tags[num_langs++] = "*"; /* it's OK; this won't be freed */
1576
1577                 /* compute decimal_places */
1578                 for (max_q = 1, decimal_places = 0;
1579                      max_q < num_langs && decimal_places <= MAX_DECIMAL_PLACES;
1580                      decimal_places++, max_q *= 10)
1581                         ;
1582
1583                 xsnprintf(q_format, sizeof(q_format), ";q=0.%%0%dd", decimal_places);
1584
1585                 strbuf_addstr(buf, "Accept-Language: ");
1586
1587                 for (i = 0; i < num_langs; i++) {
1588                         if (i > 0)
1589                                 strbuf_addstr(buf, ", ");
1590
1591                         strbuf_addstr(buf, language_tags[i]);
1592
1593                         if (i > 0)
1594                                 strbuf_addf(buf, q_format, max_q - i);
1595
1596                         if (buf->len > MAX_ACCEPT_LANGUAGE_HEADER_SIZE) {
1597                                 strbuf_remove(buf, last_buf_len, buf->len - last_buf_len);
1598                                 break;
1599                         }
1600
1601                         last_buf_len = buf->len;
1602                 }
1603         }
1604
1605         /* free language tags -- last one is a static '*' */
1606         for (i = 0; i < num_langs - 1; i++)
1607                 free(language_tags[i]);
1608         free(language_tags);
1609 }
1610
1611 /*
1612  * Get an Accept-Language header which indicates user's preferred languages.
1613  *
1614  * Examples:
1615  *   LANGUAGE= -> ""
1616  *   LANGUAGE=ko:en -> "Accept-Language: ko, en; q=0.9, *; q=0.1"
1617  *   LANGUAGE=ko_KR.UTF-8:sr@latin -> "Accept-Language: ko-KR, sr; q=0.9, *; q=0.1"
1618  *   LANGUAGE=ko LANG=en_US.UTF-8 -> "Accept-Language: ko, *; q=0.1"
1619  *   LANGUAGE= LANG=en_US.UTF-8 -> "Accept-Language: en-US, *; q=0.1"
1620  *   LANGUAGE= LANG=C -> ""
1621  */
1622 static const char *get_accept_language(void)
1623 {
1624         if (!cached_accept_language) {
1625                 struct strbuf buf = STRBUF_INIT;
1626                 write_accept_language(&buf);
1627                 if (buf.len > 0)
1628                         cached_accept_language = strbuf_detach(&buf, NULL);
1629         }
1630
1631         return cached_accept_language;
1632 }
1633
1634 static void http_opt_request_remainder(CURL *curl, off_t pos)
1635 {
1636         char buf[128];
1637         xsnprintf(buf, sizeof(buf), "%"PRIuMAX"-", (uintmax_t)pos);
1638         curl_easy_setopt(curl, CURLOPT_RANGE, buf);
1639 }
1640
1641 /* http_request() targets */
1642 #define HTTP_REQUEST_STRBUF     0
1643 #define HTTP_REQUEST_FILE       1
1644
1645 static int http_request(const char *url,
1646                         void *result, int target,
1647                         const struct http_get_options *options)
1648 {
1649         struct active_request_slot *slot;
1650         struct slot_results results;
1651         struct curl_slist *headers = http_copy_default_headers();
1652         struct strbuf buf = STRBUF_INIT;
1653         const char *accept_language;
1654         int ret;
1655
1656         slot = get_active_slot();
1657         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1658
1659         if (result == NULL) {
1660                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
1661         } else {
1662                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
1663                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
1664
1665                 if (target == HTTP_REQUEST_FILE) {
1666                         off_t posn = ftello(result);
1667                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1668                                          fwrite);
1669                         if (posn > 0)
1670                                 http_opt_request_remainder(slot->curl, posn);
1671                 } else
1672                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1673                                          fwrite_buffer);
1674         }
1675
1676         accept_language = get_accept_language();
1677
1678         if (accept_language)
1679                 headers = curl_slist_append(headers, accept_language);
1680
1681         strbuf_addstr(&buf, "Pragma:");
1682         if (options && options->no_cache)
1683                 strbuf_addstr(&buf, " no-cache");
1684         if (options && options->keep_error)
1685                 curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1686         if (options && options->initial_request &&
1687             http_follow_config == HTTP_FOLLOW_INITIAL)
1688                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 1);
1689
1690         headers = curl_slist_append(headers, buf.buf);
1691
1692         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
1693         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1694         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "gzip");
1695
1696         ret = run_one_slot(slot, &results);
1697
1698         if (options && options->content_type) {
1699                 struct strbuf raw = STRBUF_INIT;
1700                 curlinfo_strbuf(slot->curl, CURLINFO_CONTENT_TYPE, &raw);
1701                 extract_content_type(&raw, options->content_type,
1702                                      options->charset);
1703                 strbuf_release(&raw);
1704         }
1705
1706         if (options && options->effective_url)
1707                 curlinfo_strbuf(slot->curl, CURLINFO_EFFECTIVE_URL,
1708                                 options->effective_url);
1709
1710         curl_slist_free_all(headers);
1711         strbuf_release(&buf);
1712
1713         return ret;
1714 }
1715
1716 /*
1717  * Update the "base" url to a more appropriate value, as deduced by
1718  * redirects seen when requesting a URL starting with "url".
1719  *
1720  * The "asked" parameter is a URL that we asked curl to access, and must begin
1721  * with "base".
1722  *
1723  * The "got" parameter is the URL that curl reported to us as where we ended
1724  * up.
1725  *
1726  * Returns 1 if we updated the base url, 0 otherwise.
1727  *
1728  * Our basic strategy is to compare "base" and "asked" to find the bits
1729  * specific to our request. We then strip those bits off of "got" to yield the
1730  * new base. So for example, if our base is "http://example.com/foo.git",
1731  * and we ask for "http://example.com/foo.git/info/refs", we might end up
1732  * with "https://other.example.com/foo.git/info/refs". We would want the
1733  * new URL to become "https://other.example.com/foo.git".
1734  *
1735  * Note that this assumes a sane redirect scheme. It's entirely possible
1736  * in the example above to end up at a URL that does not even end in
1737  * "info/refs".  In such a case we die. There's not much we can do, such a
1738  * scheme is unlikely to represent a real git repository, and failing to
1739  * rewrite the base opens options for malicious redirects to do funny things.
1740  */
1741 static int update_url_from_redirect(struct strbuf *base,
1742                                     const char *asked,
1743                                     const struct strbuf *got)
1744 {
1745         const char *tail;
1746         size_t new_len;
1747
1748         if (!strcmp(asked, got->buf))
1749                 return 0;
1750
1751         if (!skip_prefix(asked, base->buf, &tail))
1752                 die("BUG: update_url_from_redirect: %s is not a superset of %s",
1753                     asked, base->buf);
1754
1755         new_len = got->len;
1756         if (!strip_suffix_mem(got->buf, &new_len, tail))
1757                 die(_("unable to update url base from redirection:\n"
1758                       "  asked for: %s\n"
1759                       "   redirect: %s"),
1760                     asked, got->buf);
1761
1762         strbuf_reset(base);
1763         strbuf_add(base, got->buf, new_len);
1764
1765         return 1;
1766 }
1767
1768 static int http_request_reauth(const char *url,
1769                                void *result, int target,
1770                                struct http_get_options *options)
1771 {
1772         int ret = http_request(url, result, target, options);
1773
1774         if (ret != HTTP_OK && ret != HTTP_REAUTH)
1775                 return ret;
1776
1777         if (options && options->effective_url && options->base_url) {
1778                 if (update_url_from_redirect(options->base_url,
1779                                              url, options->effective_url)) {
1780                         credential_from_url(&http_auth, options->base_url->buf);
1781                         url = options->effective_url->buf;
1782                 }
1783         }
1784
1785         if (ret != HTTP_REAUTH)
1786                 return ret;
1787
1788         /*
1789          * If we are using KEEP_ERROR, the previous request may have
1790          * put cruft into our output stream; we should clear it out before
1791          * making our next request. We only know how to do this for
1792          * the strbuf case, but that is enough to satisfy current callers.
1793          */
1794         if (options && options->keep_error) {
1795                 switch (target) {
1796                 case HTTP_REQUEST_STRBUF:
1797                         strbuf_reset(result);
1798                         break;
1799                 default:
1800                         die("BUG: HTTP_KEEP_ERROR is only supported with strbufs");
1801                 }
1802         }
1803
1804         credential_fill(&http_auth);
1805
1806         return http_request(url, result, target, options);
1807 }
1808
1809 int http_get_strbuf(const char *url,
1810                     struct strbuf *result,
1811                     struct http_get_options *options)
1812 {
1813         return http_request_reauth(url, result, HTTP_REQUEST_STRBUF, options);
1814 }
1815
1816 /*
1817  * Downloads a URL and stores the result in the given file.
1818  *
1819  * If a previous interrupted download is detected (i.e. a previous temporary
1820  * file is still around) the download is resumed.
1821  */
1822 static int http_get_file(const char *url, const char *filename,
1823                          struct http_get_options *options)
1824 {
1825         int ret;
1826         struct strbuf tmpfile = STRBUF_INIT;
1827         FILE *result;
1828
1829         strbuf_addf(&tmpfile, "%s.temp", filename);
1830         result = fopen(tmpfile.buf, "a");
1831         if (!result) {
1832                 error("Unable to open local file %s", tmpfile.buf);
1833                 ret = HTTP_ERROR;
1834                 goto cleanup;
1835         }
1836
1837         ret = http_request_reauth(url, result, HTTP_REQUEST_FILE, options);
1838         fclose(result);
1839
1840         if (ret == HTTP_OK && finalize_object_file(tmpfile.buf, filename))
1841                 ret = HTTP_ERROR;
1842 cleanup:
1843         strbuf_release(&tmpfile);
1844         return ret;
1845 }
1846
1847 int http_fetch_ref(const char *base, struct ref *ref)
1848 {
1849         struct http_get_options options = {0};
1850         char *url;
1851         struct strbuf buffer = STRBUF_INIT;
1852         int ret = -1;
1853
1854         options.no_cache = 1;
1855
1856         url = quote_ref_url(base, ref->name);
1857         if (http_get_strbuf(url, &buffer, &options) == HTTP_OK) {
1858                 strbuf_rtrim(&buffer);
1859                 if (buffer.len == 40)
1860                         ret = get_oid_hex(buffer.buf, &ref->old_oid);
1861                 else if (starts_with(buffer.buf, "ref: ")) {
1862                         ref->symref = xstrdup(buffer.buf + 5);
1863                         ret = 0;
1864                 }
1865         }
1866
1867         strbuf_release(&buffer);
1868         free(url);
1869         return ret;
1870 }
1871
1872 /* Helpers for fetching packs */
1873 static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
1874 {
1875         char *url, *tmp;
1876         struct strbuf buf = STRBUF_INIT;
1877
1878         if (http_is_verbose)
1879                 fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
1880
1881         end_url_with_slash(&buf, base_url);
1882         strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
1883         url = strbuf_detach(&buf, NULL);
1884
1885         strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
1886         tmp = strbuf_detach(&buf, NULL);
1887
1888         if (http_get_file(url, tmp, NULL) != HTTP_OK) {
1889                 error("Unable to get pack index %s", url);
1890                 free(tmp);
1891                 tmp = NULL;
1892         }
1893
1894         free(url);
1895         return tmp;
1896 }
1897
1898 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
1899         unsigned char *sha1, const char *base_url)
1900 {
1901         struct packed_git *new_pack;
1902         char *tmp_idx = NULL;
1903         int ret;
1904
1905         if (has_pack_index(sha1)) {
1906                 new_pack = parse_pack_index(sha1, sha1_pack_index_name(sha1));
1907                 if (!new_pack)
1908                         return -1; /* parse_pack_index() already issued error message */
1909                 goto add_pack;
1910         }
1911
1912         tmp_idx = fetch_pack_index(sha1, base_url);
1913         if (!tmp_idx)
1914                 return -1;
1915
1916         new_pack = parse_pack_index(sha1, tmp_idx);
1917         if (!new_pack) {
1918                 unlink(tmp_idx);
1919                 free(tmp_idx);
1920
1921                 return -1; /* parse_pack_index() already issued error message */
1922         }
1923
1924         ret = verify_pack_index(new_pack);
1925         if (!ret) {
1926                 close_pack_index(new_pack);
1927                 ret = finalize_object_file(tmp_idx, sha1_pack_index_name(sha1));
1928         }
1929         free(tmp_idx);
1930         if (ret)
1931                 return -1;
1932
1933 add_pack:
1934         new_pack->next = *packs_head;
1935         *packs_head = new_pack;
1936         return 0;
1937 }
1938
1939 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
1940 {
1941         struct http_get_options options = {0};
1942         int ret = 0, i = 0;
1943         char *url, *data;
1944         struct strbuf buf = STRBUF_INIT;
1945         unsigned char sha1[20];
1946
1947         end_url_with_slash(&buf, base_url);
1948         strbuf_addstr(&buf, "objects/info/packs");
1949         url = strbuf_detach(&buf, NULL);
1950
1951         options.no_cache = 1;
1952         ret = http_get_strbuf(url, &buf, &options);
1953         if (ret != HTTP_OK)
1954                 goto cleanup;
1955
1956         data = buf.buf;
1957         while (i < buf.len) {
1958                 switch (data[i]) {
1959                 case 'P':
1960                         i++;
1961                         if (i + 52 <= buf.len &&
1962                             starts_with(data + i, " pack-") &&
1963                             starts_with(data + i + 46, ".pack\n")) {
1964                                 get_sha1_hex(data + i + 6, sha1);
1965                                 fetch_and_setup_pack_index(packs_head, sha1,
1966                                                       base_url);
1967                                 i += 51;
1968                                 break;
1969                         }
1970                 default:
1971                         while (i < buf.len && data[i] != '\n')
1972                                 i++;
1973                 }
1974                 i++;
1975         }
1976
1977 cleanup:
1978         free(url);
1979         return ret;
1980 }
1981
1982 void release_http_pack_request(struct http_pack_request *preq)
1983 {
1984         if (preq->packfile != NULL) {
1985                 fclose(preq->packfile);
1986                 preq->packfile = NULL;
1987         }
1988         preq->slot = NULL;
1989         free(preq->url);
1990         free(preq);
1991 }
1992
1993 int finish_http_pack_request(struct http_pack_request *preq)
1994 {
1995         struct packed_git **lst;
1996         struct packed_git *p = preq->target;
1997         char *tmp_idx;
1998         size_t len;
1999         struct child_process ip = CHILD_PROCESS_INIT;
2000         const char *ip_argv[8];
2001
2002         close_pack_index(p);
2003
2004         fclose(preq->packfile);
2005         preq->packfile = NULL;
2006
2007         lst = preq->lst;
2008         while (*lst != p)
2009                 lst = &((*lst)->next);
2010         *lst = (*lst)->next;
2011
2012         if (!strip_suffix(preq->tmpfile, ".pack.temp", &len))
2013                 die("BUG: pack tmpfile does not end in .pack.temp?");
2014         tmp_idx = xstrfmt("%.*s.idx.temp", (int)len, preq->tmpfile);
2015
2016         ip_argv[0] = "index-pack";
2017         ip_argv[1] = "-o";
2018         ip_argv[2] = tmp_idx;
2019         ip_argv[3] = preq->tmpfile;
2020         ip_argv[4] = NULL;
2021
2022         ip.argv = ip_argv;
2023         ip.git_cmd = 1;
2024         ip.no_stdin = 1;
2025         ip.no_stdout = 1;
2026
2027         if (run_command(&ip)) {
2028                 unlink(preq->tmpfile);
2029                 unlink(tmp_idx);
2030                 free(tmp_idx);
2031                 return -1;
2032         }
2033
2034         unlink(sha1_pack_index_name(p->sha1));
2035
2036         if (finalize_object_file(preq->tmpfile, sha1_pack_name(p->sha1))
2037          || finalize_object_file(tmp_idx, sha1_pack_index_name(p->sha1))) {
2038                 free(tmp_idx);
2039                 return -1;
2040         }
2041
2042         install_packed_git(p);
2043         free(tmp_idx);
2044         return 0;
2045 }
2046
2047 struct http_pack_request *new_http_pack_request(
2048         struct packed_git *target, const char *base_url)
2049 {
2050         off_t prev_posn = 0;
2051         struct strbuf buf = STRBUF_INIT;
2052         struct http_pack_request *preq;
2053
2054         preq = xcalloc(1, sizeof(*preq));
2055         preq->target = target;
2056
2057         end_url_with_slash(&buf, base_url);
2058         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
2059                 sha1_to_hex(target->sha1));
2060         preq->url = strbuf_detach(&buf, NULL);
2061
2062         snprintf(preq->tmpfile, sizeof(preq->tmpfile), "%s.temp",
2063                 sha1_pack_name(target->sha1));
2064         preq->packfile = fopen(preq->tmpfile, "a");
2065         if (!preq->packfile) {
2066                 error("Unable to open local file %s for pack",
2067                       preq->tmpfile);
2068                 goto abort;
2069         }
2070
2071         preq->slot = get_active_slot();
2072         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
2073         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
2074         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
2075         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
2076                 no_pragma_header);
2077
2078         /*
2079          * If there is data present from a previous transfer attempt,
2080          * resume where it left off
2081          */
2082         prev_posn = ftello(preq->packfile);
2083         if (prev_posn>0) {
2084                 if (http_is_verbose)
2085                         fprintf(stderr,
2086                                 "Resuming fetch of pack %s at byte %"PRIuMAX"\n",
2087                                 sha1_to_hex(target->sha1), (uintmax_t)prev_posn);
2088                 http_opt_request_remainder(preq->slot->curl, prev_posn);
2089         }
2090
2091         return preq;
2092
2093 abort:
2094         free(preq->url);
2095         free(preq);
2096         return NULL;
2097 }
2098
2099 /* Helpers for fetching objects (loose) */
2100 static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
2101                                void *data)
2102 {
2103         unsigned char expn[4096];
2104         size_t size = eltsize * nmemb;
2105         int posn = 0;
2106         struct http_object_request *freq = data;
2107         struct active_request_slot *slot = freq->slot;
2108
2109         if (slot) {
2110                 CURLcode c = curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE,
2111                                                 &slot->http_code);
2112                 if (c != CURLE_OK)
2113                         die("BUG: curl_easy_getinfo for HTTP code failed: %s",
2114                                 curl_easy_strerror(c));
2115                 if (slot->http_code >= 300)
2116                         return size;
2117         }
2118
2119         do {
2120                 ssize_t retval = xwrite(freq->localfile,
2121                                         (char *) ptr + posn, size - posn);
2122                 if (retval < 0)
2123                         return posn;
2124                 posn += retval;
2125         } while (posn < size);
2126
2127         freq->stream.avail_in = size;
2128         freq->stream.next_in = (void *)ptr;
2129         do {
2130                 freq->stream.next_out = expn;
2131                 freq->stream.avail_out = sizeof(expn);
2132                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
2133                 git_SHA1_Update(&freq->c, expn,
2134                                 sizeof(expn) - freq->stream.avail_out);
2135         } while (freq->stream.avail_in && freq->zret == Z_OK);
2136         return size;
2137 }
2138
2139 struct http_object_request *new_http_object_request(const char *base_url,
2140         unsigned char *sha1)
2141 {
2142         char *hex = sha1_to_hex(sha1);
2143         const char *filename;
2144         char prevfile[PATH_MAX];
2145         int prevlocal;
2146         char prev_buf[PREV_BUF_SIZE];
2147         ssize_t prev_read = 0;
2148         off_t prev_posn = 0;
2149         struct http_object_request *freq;
2150
2151         freq = xcalloc(1, sizeof(*freq));
2152         hashcpy(freq->sha1, sha1);
2153         freq->localfile = -1;
2154
2155         filename = sha1_file_name(sha1);
2156         snprintf(freq->tmpfile, sizeof(freq->tmpfile),
2157                  "%s.temp", filename);
2158
2159         snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
2160         unlink_or_warn(prevfile);
2161         rename(freq->tmpfile, prevfile);
2162         unlink_or_warn(freq->tmpfile);
2163
2164         if (freq->localfile != -1)
2165                 error("fd leakage in start: %d", freq->localfile);
2166         freq->localfile = open(freq->tmpfile,
2167                                O_WRONLY | O_CREAT | O_EXCL, 0666);
2168         /*
2169          * This could have failed due to the "lazy directory creation";
2170          * try to mkdir the last path component.
2171          */
2172         if (freq->localfile < 0 && errno == ENOENT) {
2173                 char *dir = strrchr(freq->tmpfile, '/');
2174                 if (dir) {
2175                         *dir = 0;
2176                         mkdir(freq->tmpfile, 0777);
2177                         *dir = '/';
2178                 }
2179                 freq->localfile = open(freq->tmpfile,
2180                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
2181         }
2182
2183         if (freq->localfile < 0) {
2184                 error_errno("Couldn't create temporary file %s", freq->tmpfile);
2185                 goto abort;
2186         }
2187
2188         git_inflate_init(&freq->stream);
2189
2190         git_SHA1_Init(&freq->c);
2191
2192         freq->url = get_remote_object_url(base_url, hex, 0);
2193
2194         /*
2195          * If a previous temp file is present, process what was already
2196          * fetched.
2197          */
2198         prevlocal = open(prevfile, O_RDONLY);
2199         if (prevlocal != -1) {
2200                 do {
2201                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
2202                         if (prev_read>0) {
2203                                 if (fwrite_sha1_file(prev_buf,
2204                                                      1,
2205                                                      prev_read,
2206                                                      freq) == prev_read) {
2207                                         prev_posn += prev_read;
2208                                 } else {
2209                                         prev_read = -1;
2210                                 }
2211                         }
2212                 } while (prev_read > 0);
2213                 close(prevlocal);
2214         }
2215         unlink_or_warn(prevfile);
2216
2217         /*
2218          * Reset inflate/SHA1 if there was an error reading the previous temp
2219          * file; also rewind to the beginning of the local file.
2220          */
2221         if (prev_read == -1) {
2222                 memset(&freq->stream, 0, sizeof(freq->stream));
2223                 git_inflate_init(&freq->stream);
2224                 git_SHA1_Init(&freq->c);
2225                 if (prev_posn>0) {
2226                         prev_posn = 0;
2227                         lseek(freq->localfile, 0, SEEK_SET);
2228                         if (ftruncate(freq->localfile, 0) < 0) {
2229                                 error_errno("Couldn't truncate temporary file %s",
2230                                             freq->tmpfile);
2231                                 goto abort;
2232                         }
2233                 }
2234         }
2235
2236         freq->slot = get_active_slot();
2237
2238         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
2239         curl_easy_setopt(freq->slot->curl, CURLOPT_FAILONERROR, 0);
2240         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
2241         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
2242         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
2243         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
2244
2245         /*
2246          * If we have successfully processed data from a previous fetch
2247          * attempt, only fetch the data we don't already have.
2248          */
2249         if (prev_posn>0) {
2250                 if (http_is_verbose)
2251                         fprintf(stderr,
2252                                 "Resuming fetch of object %s at byte %"PRIuMAX"\n",
2253                                 hex, (uintmax_t)prev_posn);
2254                 http_opt_request_remainder(freq->slot->curl, prev_posn);
2255         }
2256
2257         return freq;
2258
2259 abort:
2260         free(freq->url);
2261         free(freq);
2262         return NULL;
2263 }
2264
2265 void process_http_object_request(struct http_object_request *freq)
2266 {
2267         if (freq->slot == NULL)
2268                 return;
2269         freq->curl_result = freq->slot->curl_result;
2270         freq->http_code = freq->slot->http_code;
2271         freq->slot = NULL;
2272 }
2273
2274 int finish_http_object_request(struct http_object_request *freq)
2275 {
2276         struct stat st;
2277
2278         close(freq->localfile);
2279         freq->localfile = -1;
2280
2281         process_http_object_request(freq);
2282
2283         if (freq->http_code == 416) {
2284                 warning("requested range invalid; we may already have all the data.");
2285         } else if (freq->curl_result != CURLE_OK) {
2286                 if (stat(freq->tmpfile, &st) == 0)
2287                         if (st.st_size == 0)
2288                                 unlink_or_warn(freq->tmpfile);
2289                 return -1;
2290         }
2291
2292         git_inflate_end(&freq->stream);
2293         git_SHA1_Final(freq->real_sha1, &freq->c);
2294         if (freq->zret != Z_STREAM_END) {
2295                 unlink_or_warn(freq->tmpfile);
2296                 return -1;
2297         }
2298         if (hashcmp(freq->sha1, freq->real_sha1)) {
2299                 unlink_or_warn(freq->tmpfile);
2300                 return -1;
2301         }
2302         freq->rename =
2303                 finalize_object_file(freq->tmpfile, sha1_file_name(freq->sha1));
2304
2305         return freq->rename;
2306 }
2307
2308 void abort_http_object_request(struct http_object_request *freq)
2309 {
2310         unlink_or_warn(freq->tmpfile);
2311
2312         release_http_object_request(freq);
2313 }
2314
2315 void release_http_object_request(struct http_object_request *freq)
2316 {
2317         if (freq->localfile != -1) {
2318                 close(freq->localfile);
2319                 freq->localfile = -1;
2320         }
2321         if (freq->url != NULL) {
2322                 free(freq->url);
2323                 freq->url = NULL;
2324         }
2325         if (freq->slot != NULL) {
2326                 freq->slot->callback_func = NULL;
2327                 freq->slot->callback_data = NULL;
2328                 release_active_slot(freq->slot);
2329                 freq->slot = NULL;
2330         }
2331 }