remote-curl: fall back to basic auth if Negotiate fails
[git] / http.c
1 #include "git-compat-util.h"
2 #include "http.h"
3 #include "config.h"
4 #include "pack.h"
5 #include "sideband.h"
6 #include "run-command.h"
7 #include "url.h"
8 #include "urlmatch.h"
9 #include "credential.h"
10 #include "version.h"
11 #include "pkt-line.h"
12 #include "gettext.h"
13 #include "transport.h"
14 #include "packfile.h"
15 #include "protocol.h"
16 #include "string-list.h"
17 #include "object-store.h"
18
19 static struct trace_key trace_curl = TRACE_KEY_INIT(CURL);
20 static int trace_curl_data = 1;
21 static int trace_curl_redact = 1;
22 #if LIBCURL_VERSION_NUM >= 0x070a08
23 long int git_curl_ipresolve = CURL_IPRESOLVE_WHATEVER;
24 #else
25 long int git_curl_ipresolve;
26 #endif
27 int active_requests;
28 int http_is_verbose;
29 ssize_t http_post_buffer = 16 * LARGE_PACKET_MAX;
30
31 #if LIBCURL_VERSION_NUM >= 0x070a06
32 #define LIBCURL_CAN_HANDLE_AUTH_ANY
33 #endif
34
35 static int min_curl_sessions = 1;
36 static int curl_session_count;
37 #ifdef USE_CURL_MULTI
38 static int max_requests = -1;
39 static CURLM *curlm;
40 #endif
41 #ifndef NO_CURL_EASY_DUPHANDLE
42 static CURL *curl_default;
43 #endif
44
45 #define PREV_BUF_SIZE 4096
46
47 char curl_errorstr[CURL_ERROR_SIZE];
48
49 static int curl_ssl_verify = -1;
50 static int curl_ssl_try;
51 static const char *curl_http_version = NULL;
52 static const char *ssl_cert;
53 static const char *ssl_cipherlist;
54 static const char *ssl_version;
55 static struct {
56         const char *name;
57         long ssl_version;
58 } sslversions[] = {
59         { "sslv2", CURL_SSLVERSION_SSLv2 },
60         { "sslv3", CURL_SSLVERSION_SSLv3 },
61         { "tlsv1", CURL_SSLVERSION_TLSv1 },
62 #if LIBCURL_VERSION_NUM >= 0x072200
63         { "tlsv1.0", CURL_SSLVERSION_TLSv1_0 },
64         { "tlsv1.1", CURL_SSLVERSION_TLSv1_1 },
65         { "tlsv1.2", CURL_SSLVERSION_TLSv1_2 },
66 #endif
67 #if LIBCURL_VERSION_NUM >= 0x073400
68         { "tlsv1.3", CURL_SSLVERSION_TLSv1_3 },
69 #endif
70 };
71 #if LIBCURL_VERSION_NUM >= 0x070903
72 static const char *ssl_key;
73 #endif
74 #if LIBCURL_VERSION_NUM >= 0x070908
75 static const char *ssl_capath;
76 #endif
77 #if LIBCURL_VERSION_NUM >= 0x071304
78 static const char *curl_no_proxy;
79 #endif
80 #if LIBCURL_VERSION_NUM >= 0x072c00
81 static const char *ssl_pinnedkey;
82 #endif
83 static const char *ssl_cainfo;
84 static long curl_low_speed_limit = -1;
85 static long curl_low_speed_time = -1;
86 static int curl_ftp_no_epsv;
87 static const char *curl_http_proxy;
88 static const char *http_proxy_authmethod;
89
90 static const char *http_proxy_ssl_cert;
91 static const char *http_proxy_ssl_key;
92 static const char *http_proxy_ssl_ca_info;
93 static struct credential proxy_cert_auth = CREDENTIAL_INIT;
94 static int proxy_ssl_cert_password_required;
95
96 static struct {
97         const char *name;
98         long curlauth_param;
99 } proxy_authmethods[] = {
100         { "basic", CURLAUTH_BASIC },
101         { "digest", CURLAUTH_DIGEST },
102         { "negotiate", CURLAUTH_GSSNEGOTIATE },
103         { "ntlm", CURLAUTH_NTLM },
104 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
105         { "anyauth", CURLAUTH_ANY },
106 #endif
107         /*
108          * CURLAUTH_DIGEST_IE has no corresponding command-line option in
109          * curl(1) and is not included in CURLAUTH_ANY, so we leave it out
110          * here, too
111          */
112 };
113 #ifdef CURLGSSAPI_DELEGATION_FLAG
114 static const char *curl_deleg;
115 static struct {
116         const char *name;
117         long curl_deleg_param;
118 } curl_deleg_levels[] = {
119         { "none", CURLGSSAPI_DELEGATION_NONE },
120         { "policy", CURLGSSAPI_DELEGATION_POLICY_FLAG },
121         { "always", CURLGSSAPI_DELEGATION_FLAG },
122 };
123 #endif
124
125 static struct credential proxy_auth = CREDENTIAL_INIT;
126 static const char *curl_proxyuserpwd;
127 static const char *curl_cookie_file;
128 static int curl_save_cookies;
129 struct credential http_auth = CREDENTIAL_INIT;
130 static int http_proactive_auth;
131 static const char *user_agent;
132 static int curl_empty_auth = -1;
133
134 enum http_follow_config http_follow_config = HTTP_FOLLOW_INITIAL;
135
136 #if LIBCURL_VERSION_NUM >= 0x071700
137 /* Use CURLOPT_KEYPASSWD as is */
138 #elif LIBCURL_VERSION_NUM >= 0x070903
139 #define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
140 #else
141 #define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
142 #endif
143
144 static struct credential cert_auth = CREDENTIAL_INIT;
145 static int ssl_cert_password_required;
146 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
147 static unsigned long http_auth_methods = CURLAUTH_ANY;
148 static int http_auth_methods_restricted;
149 /* Modes for which empty_auth cannot actually help us. */
150 static unsigned long empty_auth_useless =
151         CURLAUTH_BASIC
152 #ifdef CURLAUTH_DIGEST_IE
153         | CURLAUTH_DIGEST_IE
154 #endif
155         | CURLAUTH_DIGEST;
156 #endif
157
158 static struct curl_slist *pragma_header;
159 static struct curl_slist *no_pragma_header;
160 static struct string_list extra_http_headers = STRING_LIST_INIT_DUP;
161
162 static struct active_request_slot *active_queue_head;
163
164 static char *cached_accept_language;
165
166 static char *http_ssl_backend;
167
168 static int http_schannel_check_revoke = 1;
169 /*
170  * With the backend being set to `schannel`, setting sslCAinfo would override
171  * the Certificate Store in cURL v7.60.0 and later, which is not what we want
172  * by default.
173  */
174 static int http_schannel_use_ssl_cainfo;
175
176 size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
177 {
178         size_t size = eltsize * nmemb;
179         struct buffer *buffer = buffer_;
180
181         if (size > buffer->buf.len - buffer->posn)
182                 size = buffer->buf.len - buffer->posn;
183         memcpy(ptr, buffer->buf.buf + buffer->posn, size);
184         buffer->posn += size;
185
186         return size / eltsize;
187 }
188
189 #ifndef NO_CURL_IOCTL
190 curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
191 {
192         struct buffer *buffer = clientp;
193
194         switch (cmd) {
195         case CURLIOCMD_NOP:
196                 return CURLIOE_OK;
197
198         case CURLIOCMD_RESTARTREAD:
199                 buffer->posn = 0;
200                 return CURLIOE_OK;
201
202         default:
203                 return CURLIOE_UNKNOWNCMD;
204         }
205 }
206 #endif
207
208 size_t fwrite_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
209 {
210         size_t size = eltsize * nmemb;
211         struct strbuf *buffer = buffer_;
212
213         strbuf_add(buffer, ptr, size);
214         return nmemb;
215 }
216
217 size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
218 {
219         return nmemb;
220 }
221
222 static void closedown_active_slot(struct active_request_slot *slot)
223 {
224         active_requests--;
225         slot->in_use = 0;
226 }
227
228 static void finish_active_slot(struct active_request_slot *slot)
229 {
230         closedown_active_slot(slot);
231         curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
232
233         if (slot->finished != NULL)
234                 (*slot->finished) = 1;
235
236         /* Store slot results so they can be read after the slot is reused */
237         if (slot->results != NULL) {
238                 slot->results->curl_result = slot->curl_result;
239                 slot->results->http_code = slot->http_code;
240 #if LIBCURL_VERSION_NUM >= 0x070a08
241                 curl_easy_getinfo(slot->curl, CURLINFO_HTTPAUTH_AVAIL,
242                                   &slot->results->auth_avail);
243 #else
244                 slot->results->auth_avail = 0;
245 #endif
246
247                 curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CONNECTCODE,
248                         &slot->results->http_connectcode);
249         }
250
251         /* Run callback if appropriate */
252         if (slot->callback_func != NULL)
253                 slot->callback_func(slot->callback_data);
254 }
255
256 static void xmulti_remove_handle(struct active_request_slot *slot)
257 {
258 #ifdef USE_CURL_MULTI
259         curl_multi_remove_handle(curlm, slot->curl);
260 #endif
261 }
262
263 #ifdef USE_CURL_MULTI
264 static void process_curl_messages(void)
265 {
266         int num_messages;
267         struct active_request_slot *slot;
268         CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
269
270         while (curl_message != NULL) {
271                 if (curl_message->msg == CURLMSG_DONE) {
272                         int curl_result = curl_message->data.result;
273                         slot = active_queue_head;
274                         while (slot != NULL &&
275                                slot->curl != curl_message->easy_handle)
276                                 slot = slot->next;
277                         if (slot != NULL) {
278                                 xmulti_remove_handle(slot);
279                                 slot->curl_result = curl_result;
280                                 finish_active_slot(slot);
281                         } else {
282                                 fprintf(stderr, "Received DONE message for unknown request!\n");
283                         }
284                 } else {
285                         fprintf(stderr, "Unknown CURL message received: %d\n",
286                                 (int)curl_message->msg);
287                 }
288                 curl_message = curl_multi_info_read(curlm, &num_messages);
289         }
290 }
291 #endif
292
293 static int http_options(const char *var, const char *value, void *cb)
294 {
295         if (!strcmp("http.version", var)) {
296                 return git_config_string(&curl_http_version, var, value);
297         }
298         if (!strcmp("http.sslverify", var)) {
299                 curl_ssl_verify = git_config_bool(var, value);
300                 return 0;
301         }
302         if (!strcmp("http.sslcipherlist", var))
303                 return git_config_string(&ssl_cipherlist, var, value);
304         if (!strcmp("http.sslversion", var))
305                 return git_config_string(&ssl_version, var, value);
306         if (!strcmp("http.sslcert", var))
307                 return git_config_pathname(&ssl_cert, var, value);
308 #if LIBCURL_VERSION_NUM >= 0x070903
309         if (!strcmp("http.sslkey", var))
310                 return git_config_pathname(&ssl_key, var, value);
311 #endif
312 #if LIBCURL_VERSION_NUM >= 0x070908
313         if (!strcmp("http.sslcapath", var))
314                 return git_config_pathname(&ssl_capath, var, value);
315 #endif
316         if (!strcmp("http.sslcainfo", var))
317                 return git_config_pathname(&ssl_cainfo, var, value);
318         if (!strcmp("http.sslcertpasswordprotected", var)) {
319                 ssl_cert_password_required = git_config_bool(var, value);
320                 return 0;
321         }
322         if (!strcmp("http.ssltry", var)) {
323                 curl_ssl_try = git_config_bool(var, value);
324                 return 0;
325         }
326         if (!strcmp("http.sslbackend", var)) {
327                 free(http_ssl_backend);
328                 http_ssl_backend = xstrdup_or_null(value);
329                 return 0;
330         }
331
332         if (!strcmp("http.schannelcheckrevoke", var)) {
333                 http_schannel_check_revoke = git_config_bool(var, value);
334                 return 0;
335         }
336
337         if (!strcmp("http.schannelusesslcainfo", var)) {
338                 http_schannel_use_ssl_cainfo = git_config_bool(var, value);
339                 return 0;
340         }
341
342         if (!strcmp("http.minsessions", var)) {
343                 min_curl_sessions = git_config_int(var, value);
344 #ifndef USE_CURL_MULTI
345                 if (min_curl_sessions > 1)
346                         min_curl_sessions = 1;
347 #endif
348                 return 0;
349         }
350 #ifdef USE_CURL_MULTI
351         if (!strcmp("http.maxrequests", var)) {
352                 max_requests = git_config_int(var, value);
353                 return 0;
354         }
355 #endif
356         if (!strcmp("http.lowspeedlimit", var)) {
357                 curl_low_speed_limit = (long)git_config_int(var, value);
358                 return 0;
359         }
360         if (!strcmp("http.lowspeedtime", var)) {
361                 curl_low_speed_time = (long)git_config_int(var, value);
362                 return 0;
363         }
364
365         if (!strcmp("http.noepsv", var)) {
366                 curl_ftp_no_epsv = git_config_bool(var, value);
367                 return 0;
368         }
369         if (!strcmp("http.proxy", var))
370                 return git_config_string(&curl_http_proxy, var, value);
371
372         if (!strcmp("http.proxyauthmethod", var))
373                 return git_config_string(&http_proxy_authmethod, var, value);
374
375         if (!strcmp("http.proxysslcert", var))
376                 return git_config_string(&http_proxy_ssl_cert, var, value);
377
378         if (!strcmp("http.proxysslkey", var))
379                 return git_config_string(&http_proxy_ssl_key, var, value);
380
381         if (!strcmp("http.proxysslcainfo", var))
382                 return git_config_string(&http_proxy_ssl_ca_info, var, value);
383
384         if (!strcmp("http.proxysslcertpasswordprotected", var)) {
385                 proxy_ssl_cert_password_required = git_config_bool(var, value);
386                 return 0;
387         }
388
389         if (!strcmp("http.cookiefile", var))
390                 return git_config_pathname(&curl_cookie_file, var, value);
391         if (!strcmp("http.savecookies", var)) {
392                 curl_save_cookies = git_config_bool(var, value);
393                 return 0;
394         }
395
396         if (!strcmp("http.postbuffer", var)) {
397                 http_post_buffer = git_config_ssize_t(var, value);
398                 if (http_post_buffer < 0)
399                         warning(_("negative value for http.postbuffer; defaulting to %d"), LARGE_PACKET_MAX);
400                 if (http_post_buffer < LARGE_PACKET_MAX)
401                         http_post_buffer = LARGE_PACKET_MAX;
402                 return 0;
403         }
404
405         if (!strcmp("http.useragent", var))
406                 return git_config_string(&user_agent, var, value);
407
408         if (!strcmp("http.emptyauth", var)) {
409                 if (value && !strcmp("auto", value))
410                         curl_empty_auth = -1;
411                 else
412                         curl_empty_auth = git_config_bool(var, value);
413                 return 0;
414         }
415
416         if (!strcmp("http.delegation", var)) {
417 #ifdef CURLGSSAPI_DELEGATION_FLAG
418                 return git_config_string(&curl_deleg, var, value);
419 #else
420                 warning(_("Delegation control is not supported with cURL < 7.22.0"));
421                 return 0;
422 #endif
423         }
424
425         if (!strcmp("http.pinnedpubkey", var)) {
426 #if LIBCURL_VERSION_NUM >= 0x072c00
427                 return git_config_pathname(&ssl_pinnedkey, var, value);
428 #else
429                 warning(_("Public key pinning not supported with cURL < 7.44.0"));
430                 return 0;
431 #endif
432         }
433
434         if (!strcmp("http.extraheader", var)) {
435                 if (!value) {
436                         return config_error_nonbool(var);
437                 } else if (!*value) {
438                         string_list_clear(&extra_http_headers, 0);
439                 } else {
440                         string_list_append(&extra_http_headers, value);
441                 }
442                 return 0;
443         }
444
445         if (!strcmp("http.followredirects", var)) {
446                 if (value && !strcmp(value, "initial"))
447                         http_follow_config = HTTP_FOLLOW_INITIAL;
448                 else if (git_config_bool(var, value))
449                         http_follow_config = HTTP_FOLLOW_ALWAYS;
450                 else
451                         http_follow_config = HTTP_FOLLOW_NONE;
452                 return 0;
453         }
454
455         /* Fall back on the default ones */
456         return git_default_config(var, value, cb);
457 }
458
459 static int curl_empty_auth_enabled(void)
460 {
461         if (curl_empty_auth >= 0)
462                 return curl_empty_auth;
463
464 #ifndef LIBCURL_CAN_HANDLE_AUTH_ANY
465         /*
466          * Our libcurl is too old to do AUTH_ANY in the first place;
467          * just default to turning the feature off.
468          */
469 #else
470         /*
471          * In the automatic case, kick in the empty-auth
472          * hack as long as we would potentially try some
473          * method more exotic than "Basic" or "Digest".
474          *
475          * But only do this when this is our second or
476          * subsequent request, as by then we know what
477          * methods are available.
478          */
479         if (http_auth_methods_restricted &&
480             (http_auth_methods & ~empty_auth_useless))
481                 return 1;
482 #endif
483         return 0;
484 }
485
486 static void init_curl_http_auth(CURL *result)
487 {
488         if (!http_auth.username || !*http_auth.username) {
489                 if (curl_empty_auth_enabled())
490                         curl_easy_setopt(result, CURLOPT_USERPWD, ":");
491                 return;
492         }
493
494         credential_fill(&http_auth);
495
496 #if LIBCURL_VERSION_NUM >= 0x071301
497         curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
498         curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
499 #else
500         {
501                 static struct strbuf up = STRBUF_INIT;
502                 /*
503                  * Note that we assume we only ever have a single set of
504                  * credentials in a given program run, so we do not have
505                  * to worry about updating this buffer, only setting its
506                  * initial value.
507                  */
508                 if (!up.len)
509                         strbuf_addf(&up, "%s:%s",
510                                 http_auth.username, http_auth.password);
511                 curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
512         }
513 #endif
514 }
515
516 /* *var must be free-able */
517 static void var_override(const char **var, char *value)
518 {
519         if (value) {
520                 free((void *)*var);
521                 *var = xstrdup(value);
522         }
523 }
524
525 static void set_proxyauth_name_password(CURL *result)
526 {
527 #if LIBCURL_VERSION_NUM >= 0x071301
528                 curl_easy_setopt(result, CURLOPT_PROXYUSERNAME,
529                         proxy_auth.username);
530                 curl_easy_setopt(result, CURLOPT_PROXYPASSWORD,
531                         proxy_auth.password);
532 #else
533                 struct strbuf s = STRBUF_INIT;
534
535                 strbuf_addstr_urlencode(&s, proxy_auth.username,
536                                         is_rfc3986_unreserved);
537                 strbuf_addch(&s, ':');
538                 strbuf_addstr_urlencode(&s, proxy_auth.password,
539                                         is_rfc3986_unreserved);
540                 curl_proxyuserpwd = strbuf_detach(&s, NULL);
541                 curl_easy_setopt(result, CURLOPT_PROXYUSERPWD, curl_proxyuserpwd);
542 #endif
543 }
544
545 static void init_curl_proxy_auth(CURL *result)
546 {
547         if (proxy_auth.username) {
548                 if (!proxy_auth.password)
549                         credential_fill(&proxy_auth);
550                 set_proxyauth_name_password(result);
551         }
552
553         var_override(&http_proxy_authmethod, getenv("GIT_HTTP_PROXY_AUTHMETHOD"));
554
555 #if LIBCURL_VERSION_NUM >= 0x070a07 /* CURLOPT_PROXYAUTH and CURLAUTH_ANY */
556         if (http_proxy_authmethod) {
557                 int i;
558                 for (i = 0; i < ARRAY_SIZE(proxy_authmethods); i++) {
559                         if (!strcmp(http_proxy_authmethod, proxy_authmethods[i].name)) {
560                                 curl_easy_setopt(result, CURLOPT_PROXYAUTH,
561                                                 proxy_authmethods[i].curlauth_param);
562                                 break;
563                         }
564                 }
565                 if (i == ARRAY_SIZE(proxy_authmethods)) {
566                         warning("unsupported proxy authentication method %s: using anyauth",
567                                         http_proxy_authmethod);
568                         curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
569                 }
570         }
571         else
572                 curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
573 #endif
574 }
575
576 static int has_cert_password(void)
577 {
578         if (ssl_cert == NULL || ssl_cert_password_required != 1)
579                 return 0;
580         if (!cert_auth.password) {
581                 cert_auth.protocol = xstrdup("cert");
582                 cert_auth.host = xstrdup("");
583                 cert_auth.username = xstrdup("");
584                 cert_auth.path = xstrdup(ssl_cert);
585                 credential_fill(&cert_auth);
586         }
587         return 1;
588 }
589
590 #if LIBCURL_VERSION_NUM >= 0x073400
591 static int has_proxy_cert_password(void)
592 {
593         if (http_proxy_ssl_cert == NULL || proxy_ssl_cert_password_required != 1)
594                 return 0;
595         if (!proxy_cert_auth.password) {
596                 proxy_cert_auth.protocol = xstrdup("cert");
597                 proxy_cert_auth.host = xstrdup("");
598                 proxy_cert_auth.username = xstrdup("");
599                 proxy_cert_auth.path = xstrdup(http_proxy_ssl_cert);
600                 credential_fill(&proxy_cert_auth);
601         }
602         return 1;
603 }
604 #endif
605
606 #if LIBCURL_VERSION_NUM >= 0x071900
607 static void set_curl_keepalive(CURL *c)
608 {
609         curl_easy_setopt(c, CURLOPT_TCP_KEEPALIVE, 1);
610 }
611
612 #elif LIBCURL_VERSION_NUM >= 0x071000
613 static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
614 {
615         int ka = 1;
616         int rc;
617         socklen_t len = (socklen_t)sizeof(ka);
618
619         if (type != CURLSOCKTYPE_IPCXN)
620                 return 0;
621
622         rc = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&ka, len);
623         if (rc < 0)
624                 warning_errno("unable to set SO_KEEPALIVE on socket");
625
626         return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
627 }
628
629 static void set_curl_keepalive(CURL *c)
630 {
631         curl_easy_setopt(c, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
632 }
633
634 #else
635 static void set_curl_keepalive(CURL *c)
636 {
637         /* not supported on older curl versions */
638 }
639 #endif
640
641 static void redact_sensitive_header(struct strbuf *header)
642 {
643         const char *sensitive_header;
644
645         if (trace_curl_redact &&
646             (skip_prefix(header->buf, "Authorization:", &sensitive_header) ||
647              skip_prefix(header->buf, "Proxy-Authorization:", &sensitive_header))) {
648                 /* The first token is the type, which is OK to log */
649                 while (isspace(*sensitive_header))
650                         sensitive_header++;
651                 while (*sensitive_header && !isspace(*sensitive_header))
652                         sensitive_header++;
653                 /* Everything else is opaque and possibly sensitive */
654                 strbuf_setlen(header,  sensitive_header - header->buf);
655                 strbuf_addstr(header, " <redacted>");
656         } else if (trace_curl_redact &&
657                    skip_prefix(header->buf, "Cookie:", &sensitive_header)) {
658                 struct strbuf redacted_header = STRBUF_INIT;
659                 const char *cookie;
660
661                 while (isspace(*sensitive_header))
662                         sensitive_header++;
663
664                 cookie = sensitive_header;
665
666                 while (cookie) {
667                         char *equals;
668                         char *semicolon = strstr(cookie, "; ");
669                         if (semicolon)
670                                 *semicolon = 0;
671                         equals = strchrnul(cookie, '=');
672                         if (!equals) {
673                                 /* invalid cookie, just append and continue */
674                                 strbuf_addstr(&redacted_header, cookie);
675                                 continue;
676                         }
677                         strbuf_add(&redacted_header, cookie, equals - cookie);
678                         strbuf_addstr(&redacted_header, "=<redacted>");
679                         if (semicolon) {
680                                 /*
681                                  * There are more cookies. (Or, for some
682                                  * reason, the input string ends in "; ".)
683                                  */
684                                 strbuf_addstr(&redacted_header, "; ");
685                                 cookie = semicolon + strlen("; ");
686                         } else {
687                                 cookie = NULL;
688                         }
689                 }
690
691                 strbuf_setlen(header, sensitive_header - header->buf);
692                 strbuf_addbuf(header, &redacted_header);
693         }
694 }
695
696 static void curl_dump_header(const char *text, unsigned char *ptr, size_t size, int hide_sensitive_header)
697 {
698         struct strbuf out = STRBUF_INIT;
699         struct strbuf **headers, **header;
700
701         strbuf_addf(&out, "%s, %10.10ld bytes (0x%8.8lx)\n",
702                 text, (long)size, (long)size);
703         trace_strbuf(&trace_curl, &out);
704         strbuf_reset(&out);
705         strbuf_add(&out, ptr, size);
706         headers = strbuf_split_max(&out, '\n', 0);
707
708         for (header = headers; *header; header++) {
709                 if (hide_sensitive_header)
710                         redact_sensitive_header(*header);
711                 strbuf_insertstr((*header), 0, text);
712                 strbuf_insertstr((*header), strlen(text), ": ");
713                 strbuf_rtrim((*header));
714                 strbuf_addch((*header), '\n');
715                 trace_strbuf(&trace_curl, (*header));
716         }
717         strbuf_list_free(headers);
718         strbuf_release(&out);
719 }
720
721 static void curl_dump_data(const char *text, unsigned char *ptr, size_t size)
722 {
723         size_t i;
724         struct strbuf out = STRBUF_INIT;
725         unsigned int width = 60;
726
727         strbuf_addf(&out, "%s, %10.10ld bytes (0x%8.8lx)\n",
728                 text, (long)size, (long)size);
729         trace_strbuf(&trace_curl, &out);
730
731         for (i = 0; i < size; i += width) {
732                 size_t w;
733
734                 strbuf_reset(&out);
735                 strbuf_addf(&out, "%s: ", text);
736                 for (w = 0; (w < width) && (i + w < size); w++) {
737                         unsigned char ch = ptr[i + w];
738
739                         strbuf_addch(&out,
740                                        (ch >= 0x20) && (ch < 0x80)
741                                        ? ch : '.');
742                 }
743                 strbuf_addch(&out, '\n');
744                 trace_strbuf(&trace_curl, &out);
745         }
746         strbuf_release(&out);
747 }
748
749 static int curl_trace(CURL *handle, curl_infotype type, char *data, size_t size, void *userp)
750 {
751         const char *text;
752         enum { NO_FILTER = 0, DO_FILTER = 1 };
753
754         switch (type) {
755         case CURLINFO_TEXT:
756                 trace_printf_key(&trace_curl, "== Info: %s", data);
757                 break;
758         case CURLINFO_HEADER_OUT:
759                 text = "=> Send header";
760                 curl_dump_header(text, (unsigned char *)data, size, DO_FILTER);
761                 break;
762         case CURLINFO_DATA_OUT:
763                 if (trace_curl_data) {
764                         text = "=> Send data";
765                         curl_dump_data(text, (unsigned char *)data, size);
766                 }
767                 break;
768         case CURLINFO_SSL_DATA_OUT:
769                 if (trace_curl_data) {
770                         text = "=> Send SSL data";
771                         curl_dump_data(text, (unsigned char *)data, size);
772                 }
773                 break;
774         case CURLINFO_HEADER_IN:
775                 text = "<= Recv header";
776                 curl_dump_header(text, (unsigned char *)data, size, NO_FILTER);
777                 break;
778         case CURLINFO_DATA_IN:
779                 if (trace_curl_data) {
780                         text = "<= Recv data";
781                         curl_dump_data(text, (unsigned char *)data, size);
782                 }
783                 break;
784         case CURLINFO_SSL_DATA_IN:
785                 if (trace_curl_data) {
786                         text = "<= Recv SSL data";
787                         curl_dump_data(text, (unsigned char *)data, size);
788                 }
789                 break;
790
791         default:                /* we ignore unknown types by default */
792                 return 0;
793         }
794         return 0;
795 }
796
797 void http_trace_curl_no_data(void)
798 {
799         trace_override_envvar(&trace_curl, "1");
800         trace_curl_data = 0;
801 }
802
803 void setup_curl_trace(CURL *handle)
804 {
805         if (!trace_want(&trace_curl))
806                 return;
807         curl_easy_setopt(handle, CURLOPT_VERBOSE, 1L);
808         curl_easy_setopt(handle, CURLOPT_DEBUGFUNCTION, curl_trace);
809         curl_easy_setopt(handle, CURLOPT_DEBUGDATA, NULL);
810 }
811
812 #ifdef CURLPROTO_HTTP
813 static long get_curl_allowed_protocols(int from_user)
814 {
815         long allowed_protocols = 0;
816
817         if (is_transport_allowed("http", from_user))
818                 allowed_protocols |= CURLPROTO_HTTP;
819         if (is_transport_allowed("https", from_user))
820                 allowed_protocols |= CURLPROTO_HTTPS;
821         if (is_transport_allowed("ftp", from_user))
822                 allowed_protocols |= CURLPROTO_FTP;
823         if (is_transport_allowed("ftps", from_user))
824                 allowed_protocols |= CURLPROTO_FTPS;
825
826         return allowed_protocols;
827 }
828 #endif
829
830 #if LIBCURL_VERSION_NUM >=0x072f00
831 static int get_curl_http_version_opt(const char *version_string, long *opt)
832 {
833         int i;
834         static struct {
835                 const char *name;
836                 long opt_token;
837         } choice[] = {
838                 { "HTTP/1.1", CURL_HTTP_VERSION_1_1 },
839                 { "HTTP/2", CURL_HTTP_VERSION_2 }
840         };
841
842         for (i = 0; i < ARRAY_SIZE(choice); i++) {
843                 if (!strcmp(version_string, choice[i].name)) {
844                         *opt = choice[i].opt_token;
845                         return 0;
846                 }
847         }
848
849         warning("unknown value given to http.version: '%s'", version_string);
850         return -1; /* not found */
851 }
852
853 #endif
854
855 static CURL *get_curl_handle(void)
856 {
857         CURL *result = curl_easy_init();
858
859         if (!result)
860                 die("curl_easy_init failed");
861
862         if (!curl_ssl_verify) {
863                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
864                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
865         } else {
866                 /* Verify authenticity of the peer's certificate */
867                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
868                 /* The name in the cert must match whom we tried to connect */
869                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
870         }
871
872 #if LIBCURL_VERSION_NUM >= 0x072f00 // 7.47.0
873     if (curl_http_version) {
874                 long opt;
875                 if (!get_curl_http_version_opt(curl_http_version, &opt)) {
876                         /* Set request use http version */
877                         curl_easy_setopt(result, CURLOPT_HTTP_VERSION, opt);
878                 }
879     }
880 #endif
881
882 #if LIBCURL_VERSION_NUM >= 0x070907
883         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
884 #endif
885 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
886         curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
887 #endif
888
889 #ifdef CURLGSSAPI_DELEGATION_FLAG
890         if (curl_deleg) {
891                 int i;
892                 for (i = 0; i < ARRAY_SIZE(curl_deleg_levels); i++) {
893                         if (!strcmp(curl_deleg, curl_deleg_levels[i].name)) {
894                                 curl_easy_setopt(result, CURLOPT_GSSAPI_DELEGATION,
895                                                 curl_deleg_levels[i].curl_deleg_param);
896                                 break;
897                         }
898                 }
899                 if (i == ARRAY_SIZE(curl_deleg_levels))
900                         warning("Unknown delegation method '%s': using default",
901                                 curl_deleg);
902         }
903 #endif
904
905         if (http_ssl_backend && !strcmp("schannel", http_ssl_backend) &&
906             !http_schannel_check_revoke) {
907 #if LIBCURL_VERSION_NUM >= 0x072c00
908                 curl_easy_setopt(result, CURLOPT_SSL_OPTIONS, CURLSSLOPT_NO_REVOKE);
909 #else
910                 warning(_("CURLSSLOPT_NO_REVOKE not supported with cURL < 7.44.0"));
911 #endif
912         }
913
914         if (http_proactive_auth)
915                 init_curl_http_auth(result);
916
917         if (getenv("GIT_SSL_VERSION"))
918                 ssl_version = getenv("GIT_SSL_VERSION");
919         if (ssl_version && *ssl_version) {
920                 int i;
921                 for (i = 0; i < ARRAY_SIZE(sslversions); i++) {
922                         if (!strcmp(ssl_version, sslversions[i].name)) {
923                                 curl_easy_setopt(result, CURLOPT_SSLVERSION,
924                                                  sslversions[i].ssl_version);
925                                 break;
926                         }
927                 }
928                 if (i == ARRAY_SIZE(sslversions))
929                         warning("unsupported ssl version %s: using default",
930                                 ssl_version);
931         }
932
933         if (getenv("GIT_SSL_CIPHER_LIST"))
934                 ssl_cipherlist = getenv("GIT_SSL_CIPHER_LIST");
935         if (ssl_cipherlist != NULL && *ssl_cipherlist)
936                 curl_easy_setopt(result, CURLOPT_SSL_CIPHER_LIST,
937                                 ssl_cipherlist);
938
939         if (ssl_cert != NULL)
940                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
941         if (has_cert_password())
942                 curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
943 #if LIBCURL_VERSION_NUM >= 0x070903
944         if (ssl_key != NULL)
945                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
946 #endif
947 #if LIBCURL_VERSION_NUM >= 0x070908
948         if (ssl_capath != NULL)
949                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
950 #endif
951 #if LIBCURL_VERSION_NUM >= 0x072c00
952         if (ssl_pinnedkey != NULL)
953                 curl_easy_setopt(result, CURLOPT_PINNEDPUBLICKEY, ssl_pinnedkey);
954 #endif
955         if (http_ssl_backend && !strcmp("schannel", http_ssl_backend) &&
956             !http_schannel_use_ssl_cainfo) {
957                 curl_easy_setopt(result, CURLOPT_CAINFO, NULL);
958 #if LIBCURL_VERSION_NUM >= 0x073400
959                 curl_easy_setopt(result, CURLOPT_PROXY_CAINFO, NULL);
960 #endif
961         } else if (ssl_cainfo != NULL || http_proxy_ssl_ca_info != NULL) {
962                 if (ssl_cainfo != NULL)
963                         curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
964 #if LIBCURL_VERSION_NUM >= 0x073400
965                 if (http_proxy_ssl_ca_info != NULL)
966                         curl_easy_setopt(result, CURLOPT_PROXY_CAINFO, http_proxy_ssl_ca_info);
967 #endif
968         }
969
970         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
971                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
972                                  curl_low_speed_limit);
973                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
974                                  curl_low_speed_time);
975         }
976
977         curl_easy_setopt(result, CURLOPT_MAXREDIRS, 20);
978 #if LIBCURL_VERSION_NUM >= 0x071301
979         curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
980 #elif LIBCURL_VERSION_NUM >= 0x071101
981         curl_easy_setopt(result, CURLOPT_POST301, 1);
982 #endif
983 #ifdef CURLPROTO_HTTP
984         curl_easy_setopt(result, CURLOPT_REDIR_PROTOCOLS,
985                          get_curl_allowed_protocols(0));
986         curl_easy_setopt(result, CURLOPT_PROTOCOLS,
987                          get_curl_allowed_protocols(-1));
988 #else
989         warning(_("Protocol restrictions not supported with cURL < 7.19.4"));
990 #endif
991         if (getenv("GIT_CURL_VERBOSE"))
992                 http_trace_curl_no_data();
993         setup_curl_trace(result);
994         if (getenv("GIT_TRACE_CURL_NO_DATA"))
995                 trace_curl_data = 0;
996         if (!git_env_bool("GIT_TRACE_REDACT", 1))
997                 trace_curl_redact = 0;
998
999         curl_easy_setopt(result, CURLOPT_USERAGENT,
1000                 user_agent ? user_agent : git_user_agent());
1001
1002         if (curl_ftp_no_epsv)
1003                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
1004
1005 #ifdef CURLOPT_USE_SSL
1006         if (curl_ssl_try)
1007                 curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
1008 #endif
1009
1010         /*
1011          * CURL also examines these variables as a fallback; but we need to query
1012          * them here in order to decide whether to prompt for missing password (cf.
1013          * init_curl_proxy_auth()).
1014          *
1015          * Unlike many other common environment variables, these are historically
1016          * lowercase only. It appears that CURL did not know this and implemented
1017          * only uppercase variants, which was later corrected to take both - with
1018          * the exception of http_proxy, which is lowercase only also in CURL. As
1019          * the lowercase versions are the historical quasi-standard, they take
1020          * precedence here, as in CURL.
1021          */
1022         if (!curl_http_proxy) {
1023                 if (http_auth.protocol && !strcmp(http_auth.protocol, "https")) {
1024                         var_override(&curl_http_proxy, getenv("HTTPS_PROXY"));
1025                         var_override(&curl_http_proxy, getenv("https_proxy"));
1026                 } else {
1027                         var_override(&curl_http_proxy, getenv("http_proxy"));
1028                 }
1029                 if (!curl_http_proxy) {
1030                         var_override(&curl_http_proxy, getenv("ALL_PROXY"));
1031                         var_override(&curl_http_proxy, getenv("all_proxy"));
1032                 }
1033         }
1034
1035         if (curl_http_proxy && curl_http_proxy[0] == '\0') {
1036                 /*
1037                  * Handle case with the empty http.proxy value here to keep
1038                  * common code clean.
1039                  * NB: empty option disables proxying at all.
1040                  */
1041                 curl_easy_setopt(result, CURLOPT_PROXY, "");
1042         } else if (curl_http_proxy) {
1043 #if LIBCURL_VERSION_NUM >= 0x071800
1044                 if (starts_with(curl_http_proxy, "socks5h"))
1045                         curl_easy_setopt(result,
1046                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5_HOSTNAME);
1047                 else if (starts_with(curl_http_proxy, "socks5"))
1048                         curl_easy_setopt(result,
1049                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5);
1050                 else if (starts_with(curl_http_proxy, "socks4a"))
1051                         curl_easy_setopt(result,
1052                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4A);
1053                 else if (starts_with(curl_http_proxy, "socks"))
1054                         curl_easy_setopt(result,
1055                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4);
1056 #endif
1057 #if LIBCURL_VERSION_NUM >= 0x073400
1058                 else if (starts_with(curl_http_proxy, "https")) {
1059                         curl_easy_setopt(result, CURLOPT_PROXYTYPE, CURLPROXY_HTTPS);
1060
1061                         if (http_proxy_ssl_cert)
1062                                 curl_easy_setopt(result, CURLOPT_PROXY_SSLCERT, http_proxy_ssl_cert);
1063
1064                         if (http_proxy_ssl_key)
1065                                 curl_easy_setopt(result, CURLOPT_PROXY_SSLKEY, http_proxy_ssl_key);
1066
1067                         if (has_proxy_cert_password())
1068                                 curl_easy_setopt(result, CURLOPT_PROXY_KEYPASSWD, proxy_cert_auth.password);
1069                 }
1070 #endif
1071                 if (strstr(curl_http_proxy, "://"))
1072                         credential_from_url(&proxy_auth, curl_http_proxy);
1073                 else {
1074                         struct strbuf url = STRBUF_INIT;
1075                         strbuf_addf(&url, "http://%s", curl_http_proxy);
1076                         credential_from_url(&proxy_auth, url.buf);
1077                         strbuf_release(&url);
1078                 }
1079
1080                 if (!proxy_auth.host)
1081                         die("Invalid proxy URL '%s'", curl_http_proxy);
1082
1083                 curl_easy_setopt(result, CURLOPT_PROXY, proxy_auth.host);
1084 #if LIBCURL_VERSION_NUM >= 0x071304
1085                 var_override(&curl_no_proxy, getenv("NO_PROXY"));
1086                 var_override(&curl_no_proxy, getenv("no_proxy"));
1087                 curl_easy_setopt(result, CURLOPT_NOPROXY, curl_no_proxy);
1088 #endif
1089         }
1090         init_curl_proxy_auth(result);
1091
1092         set_curl_keepalive(result);
1093
1094         return result;
1095 }
1096
1097 static void set_from_env(const char **var, const char *envname)
1098 {
1099         const char *val = getenv(envname);
1100         if (val)
1101                 *var = val;
1102 }
1103
1104 void http_init(struct remote *remote, const char *url, int proactive_auth)
1105 {
1106         char *low_speed_limit;
1107         char *low_speed_time;
1108         char *normalized_url;
1109         struct urlmatch_config config = { STRING_LIST_INIT_DUP };
1110
1111         config.section = "http";
1112         config.key = NULL;
1113         config.collect_fn = http_options;
1114         config.cascade_fn = git_default_config;
1115         config.cb = NULL;
1116
1117         http_is_verbose = 0;
1118         normalized_url = url_normalize(url, &config.url);
1119
1120         git_config(urlmatch_config_entry, &config);
1121         free(normalized_url);
1122         string_list_clear(&config.vars, 1);
1123
1124 #if LIBCURL_VERSION_NUM >= 0x073800
1125         if (http_ssl_backend) {
1126                 const curl_ssl_backend **backends;
1127                 struct strbuf buf = STRBUF_INIT;
1128                 int i;
1129
1130                 switch (curl_global_sslset(-1, http_ssl_backend, &backends)) {
1131                 case CURLSSLSET_UNKNOWN_BACKEND:
1132                         strbuf_addf(&buf, _("Unsupported SSL backend '%s'. "
1133                                             "Supported SSL backends:"),
1134                                             http_ssl_backend);
1135                         for (i = 0; backends[i]; i++)
1136                                 strbuf_addf(&buf, "\n\t%s", backends[i]->name);
1137                         die("%s", buf.buf);
1138                 case CURLSSLSET_NO_BACKENDS:
1139                         die(_("Could not set SSL backend to '%s': "
1140                               "cURL was built without SSL backends"),
1141                             http_ssl_backend);
1142                 case CURLSSLSET_TOO_LATE:
1143                         die(_("Could not set SSL backend to '%s': already set"),
1144                             http_ssl_backend);
1145                 case CURLSSLSET_OK:
1146                         break; /* Okay! */
1147                 }
1148         }
1149 #endif
1150
1151         if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK)
1152                 die("curl_global_init failed");
1153
1154         http_proactive_auth = proactive_auth;
1155
1156         if (remote && remote->http_proxy)
1157                 curl_http_proxy = xstrdup(remote->http_proxy);
1158
1159         if (remote)
1160                 var_override(&http_proxy_authmethod, remote->http_proxy_authmethod);
1161
1162         pragma_header = curl_slist_append(http_copy_default_headers(),
1163                 "Pragma: no-cache");
1164         no_pragma_header = curl_slist_append(http_copy_default_headers(),
1165                 "Pragma:");
1166
1167 #ifdef USE_CURL_MULTI
1168         {
1169                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
1170                 if (http_max_requests != NULL)
1171                         max_requests = atoi(http_max_requests);
1172         }
1173
1174         curlm = curl_multi_init();
1175         if (!curlm)
1176                 die("curl_multi_init failed");
1177 #endif
1178
1179         if (getenv("GIT_SSL_NO_VERIFY"))
1180                 curl_ssl_verify = 0;
1181
1182         set_from_env(&ssl_cert, "GIT_SSL_CERT");
1183 #if LIBCURL_VERSION_NUM >= 0x070903
1184         set_from_env(&ssl_key, "GIT_SSL_KEY");
1185 #endif
1186 #if LIBCURL_VERSION_NUM >= 0x070908
1187         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
1188 #endif
1189         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
1190
1191         set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
1192
1193         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
1194         if (low_speed_limit != NULL)
1195                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
1196         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
1197         if (low_speed_time != NULL)
1198                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
1199
1200         if (curl_ssl_verify == -1)
1201                 curl_ssl_verify = 1;
1202
1203         curl_session_count = 0;
1204 #ifdef USE_CURL_MULTI
1205         if (max_requests < 1)
1206                 max_requests = DEFAULT_MAX_REQUESTS;
1207 #endif
1208
1209         set_from_env(&http_proxy_ssl_cert, "GIT_PROXY_SSL_CERT");
1210         set_from_env(&http_proxy_ssl_key, "GIT_PROXY_SSL_KEY");
1211         set_from_env(&http_proxy_ssl_ca_info, "GIT_PROXY_SSL_CAINFO");
1212
1213         if (getenv("GIT_PROXY_SSL_CERT_PASSWORD_PROTECTED"))
1214                 proxy_ssl_cert_password_required = 1;
1215
1216         if (getenv("GIT_CURL_FTP_NO_EPSV"))
1217                 curl_ftp_no_epsv = 1;
1218
1219         if (url) {
1220                 credential_from_url(&http_auth, url);
1221                 if (!ssl_cert_password_required &&
1222                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
1223                     starts_with(url, "https://"))
1224                         ssl_cert_password_required = 1;
1225         }
1226
1227 #ifndef NO_CURL_EASY_DUPHANDLE
1228         curl_default = get_curl_handle();
1229 #endif
1230 }
1231
1232 void http_cleanup(void)
1233 {
1234         struct active_request_slot *slot = active_queue_head;
1235
1236         while (slot != NULL) {
1237                 struct active_request_slot *next = slot->next;
1238                 if (slot->curl != NULL) {
1239                         xmulti_remove_handle(slot);
1240                         curl_easy_cleanup(slot->curl);
1241                 }
1242                 free(slot);
1243                 slot = next;
1244         }
1245         active_queue_head = NULL;
1246
1247 #ifndef NO_CURL_EASY_DUPHANDLE
1248         curl_easy_cleanup(curl_default);
1249 #endif
1250
1251 #ifdef USE_CURL_MULTI
1252         curl_multi_cleanup(curlm);
1253 #endif
1254         curl_global_cleanup();
1255
1256         string_list_clear(&extra_http_headers, 0);
1257
1258         curl_slist_free_all(pragma_header);
1259         pragma_header = NULL;
1260
1261         curl_slist_free_all(no_pragma_header);
1262         no_pragma_header = NULL;
1263
1264         if (curl_http_proxy) {
1265                 free((void *)curl_http_proxy);
1266                 curl_http_proxy = NULL;
1267         }
1268
1269         if (proxy_auth.password) {
1270                 memset(proxy_auth.password, 0, strlen(proxy_auth.password));
1271                 FREE_AND_NULL(proxy_auth.password);
1272         }
1273
1274         free((void *)curl_proxyuserpwd);
1275         curl_proxyuserpwd = NULL;
1276
1277         free((void *)http_proxy_authmethod);
1278         http_proxy_authmethod = NULL;
1279
1280         if (cert_auth.password != NULL) {
1281                 memset(cert_auth.password, 0, strlen(cert_auth.password));
1282                 FREE_AND_NULL(cert_auth.password);
1283         }
1284         ssl_cert_password_required = 0;
1285
1286         if (proxy_cert_auth.password != NULL) {
1287                 memset(proxy_cert_auth.password, 0, strlen(proxy_cert_auth.password));
1288                 FREE_AND_NULL(proxy_cert_auth.password);
1289         }
1290         proxy_ssl_cert_password_required = 0;
1291
1292         FREE_AND_NULL(cached_accept_language);
1293 }
1294
1295 struct active_request_slot *get_active_slot(void)
1296 {
1297         struct active_request_slot *slot = active_queue_head;
1298         struct active_request_slot *newslot;
1299
1300 #ifdef USE_CURL_MULTI
1301         int num_transfers;
1302
1303         /* Wait for a slot to open up if the queue is full */
1304         while (active_requests >= max_requests) {
1305                 curl_multi_perform(curlm, &num_transfers);
1306                 if (num_transfers < active_requests)
1307                         process_curl_messages();
1308         }
1309 #endif
1310
1311         while (slot != NULL && slot->in_use)
1312                 slot = slot->next;
1313
1314         if (slot == NULL) {
1315                 newslot = xmalloc(sizeof(*newslot));
1316                 newslot->curl = NULL;
1317                 newslot->in_use = 0;
1318                 newslot->next = NULL;
1319
1320                 slot = active_queue_head;
1321                 if (slot == NULL) {
1322                         active_queue_head = newslot;
1323                 } else {
1324                         while (slot->next != NULL)
1325                                 slot = slot->next;
1326                         slot->next = newslot;
1327                 }
1328                 slot = newslot;
1329         }
1330
1331         if (slot->curl == NULL) {
1332 #ifdef NO_CURL_EASY_DUPHANDLE
1333                 slot->curl = get_curl_handle();
1334 #else
1335                 slot->curl = curl_easy_duphandle(curl_default);
1336 #endif
1337                 curl_session_count++;
1338         }
1339
1340         active_requests++;
1341         slot->in_use = 1;
1342         slot->results = NULL;
1343         slot->finished = NULL;
1344         slot->callback_data = NULL;
1345         slot->callback_func = NULL;
1346         curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
1347         if (curl_save_cookies)
1348                 curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
1349         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
1350         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
1351         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
1352         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
1353         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
1354         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
1355         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
1356         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1357         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
1358         curl_easy_setopt(slot->curl, CURLOPT_RANGE, NULL);
1359
1360         /*
1361          * Default following to off unless "ALWAYS" is configured; this gives
1362          * callers a sane starting point, and they can tweak for individual
1363          * HTTP_FOLLOW_* cases themselves.
1364          */
1365         if (http_follow_config == HTTP_FOLLOW_ALWAYS)
1366                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 1);
1367         else
1368                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 0);
1369
1370 #if LIBCURL_VERSION_NUM >= 0x070a08
1371         curl_easy_setopt(slot->curl, CURLOPT_IPRESOLVE, git_curl_ipresolve);
1372 #endif
1373 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
1374         curl_easy_setopt(slot->curl, CURLOPT_HTTPAUTH, http_auth_methods);
1375 #endif
1376         if (http_auth.password || curl_empty_auth_enabled())
1377                 init_curl_http_auth(slot->curl);
1378
1379         return slot;
1380 }
1381
1382 int start_active_slot(struct active_request_slot *slot)
1383 {
1384 #ifdef USE_CURL_MULTI
1385         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
1386         int num_transfers;
1387
1388         if (curlm_result != CURLM_OK &&
1389             curlm_result != CURLM_CALL_MULTI_PERFORM) {
1390                 warning("curl_multi_add_handle failed: %s",
1391                         curl_multi_strerror(curlm_result));
1392                 active_requests--;
1393                 slot->in_use = 0;
1394                 return 0;
1395         }
1396
1397         /*
1398          * We know there must be something to do, since we just added
1399          * something.
1400          */
1401         curl_multi_perform(curlm, &num_transfers);
1402 #endif
1403         return 1;
1404 }
1405
1406 #ifdef USE_CURL_MULTI
1407 struct fill_chain {
1408         void *data;
1409         int (*fill)(void *);
1410         struct fill_chain *next;
1411 };
1412
1413 static struct fill_chain *fill_cfg;
1414
1415 void add_fill_function(void *data, int (*fill)(void *))
1416 {
1417         struct fill_chain *new_fill = xmalloc(sizeof(*new_fill));
1418         struct fill_chain **linkp = &fill_cfg;
1419         new_fill->data = data;
1420         new_fill->fill = fill;
1421         new_fill->next = NULL;
1422         while (*linkp)
1423                 linkp = &(*linkp)->next;
1424         *linkp = new_fill;
1425 }
1426
1427 void fill_active_slots(void)
1428 {
1429         struct active_request_slot *slot = active_queue_head;
1430
1431         while (active_requests < max_requests) {
1432                 struct fill_chain *fill;
1433                 for (fill = fill_cfg; fill; fill = fill->next)
1434                         if (fill->fill(fill->data))
1435                                 break;
1436
1437                 if (!fill)
1438                         break;
1439         }
1440
1441         while (slot != NULL) {
1442                 if (!slot->in_use && slot->curl != NULL
1443                         && curl_session_count > min_curl_sessions) {
1444                         curl_easy_cleanup(slot->curl);
1445                         slot->curl = NULL;
1446                         curl_session_count--;
1447                 }
1448                 slot = slot->next;
1449         }
1450 }
1451
1452 void step_active_slots(void)
1453 {
1454         int num_transfers;
1455         CURLMcode curlm_result;
1456
1457         do {
1458                 curlm_result = curl_multi_perform(curlm, &num_transfers);
1459         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
1460         if (num_transfers < active_requests) {
1461                 process_curl_messages();
1462                 fill_active_slots();
1463         }
1464 }
1465 #endif
1466
1467 void run_active_slot(struct active_request_slot *slot)
1468 {
1469 #ifdef USE_CURL_MULTI
1470         fd_set readfds;
1471         fd_set writefds;
1472         fd_set excfds;
1473         int max_fd;
1474         struct timeval select_timeout;
1475         int finished = 0;
1476
1477         slot->finished = &finished;
1478         while (!finished) {
1479                 step_active_slots();
1480
1481                 if (slot->in_use) {
1482 #if LIBCURL_VERSION_NUM >= 0x070f04
1483                         long curl_timeout;
1484                         curl_multi_timeout(curlm, &curl_timeout);
1485                         if (curl_timeout == 0) {
1486                                 continue;
1487                         } else if (curl_timeout == -1) {
1488                                 select_timeout.tv_sec  = 0;
1489                                 select_timeout.tv_usec = 50000;
1490                         } else {
1491                                 select_timeout.tv_sec  =  curl_timeout / 1000;
1492                                 select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
1493                         }
1494 #else
1495                         select_timeout.tv_sec  = 0;
1496                         select_timeout.tv_usec = 50000;
1497 #endif
1498
1499                         max_fd = -1;
1500                         FD_ZERO(&readfds);
1501                         FD_ZERO(&writefds);
1502                         FD_ZERO(&excfds);
1503                         curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
1504
1505                         /*
1506                          * It can happen that curl_multi_timeout returns a pathologically
1507                          * long timeout when curl_multi_fdset returns no file descriptors
1508                          * to read.  See commit message for more details.
1509                          */
1510                         if (max_fd < 0 &&
1511                             (select_timeout.tv_sec > 0 ||
1512                              select_timeout.tv_usec > 50000)) {
1513                                 select_timeout.tv_sec  = 0;
1514                                 select_timeout.tv_usec = 50000;
1515                         }
1516
1517                         select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
1518                 }
1519         }
1520 #else
1521         while (slot->in_use) {
1522                 slot->curl_result = curl_easy_perform(slot->curl);
1523                 finish_active_slot(slot);
1524         }
1525 #endif
1526 }
1527
1528 static void release_active_slot(struct active_request_slot *slot)
1529 {
1530         closedown_active_slot(slot);
1531         if (slot->curl) {
1532                 xmulti_remove_handle(slot);
1533                 if (curl_session_count > min_curl_sessions) {
1534                         curl_easy_cleanup(slot->curl);
1535                         slot->curl = NULL;
1536                         curl_session_count--;
1537                 }
1538         }
1539 #ifdef USE_CURL_MULTI
1540         fill_active_slots();
1541 #endif
1542 }
1543
1544 void finish_all_active_slots(void)
1545 {
1546         struct active_request_slot *slot = active_queue_head;
1547
1548         while (slot != NULL)
1549                 if (slot->in_use) {
1550                         run_active_slot(slot);
1551                         slot = active_queue_head;
1552                 } else {
1553                         slot = slot->next;
1554                 }
1555 }
1556
1557 /* Helpers for modifying and creating URLs */
1558 static inline int needs_quote(int ch)
1559 {
1560         if (((ch >= 'A') && (ch <= 'Z'))
1561                         || ((ch >= 'a') && (ch <= 'z'))
1562                         || ((ch >= '0') && (ch <= '9'))
1563                         || (ch == '/')
1564                         || (ch == '-')
1565                         || (ch == '.'))
1566                 return 0;
1567         return 1;
1568 }
1569
1570 static char *quote_ref_url(const char *base, const char *ref)
1571 {
1572         struct strbuf buf = STRBUF_INIT;
1573         const char *cp;
1574         int ch;
1575
1576         end_url_with_slash(&buf, base);
1577
1578         for (cp = ref; (ch = *cp) != 0; cp++)
1579                 if (needs_quote(ch))
1580                         strbuf_addf(&buf, "%%%02x", ch);
1581                 else
1582                         strbuf_addch(&buf, *cp);
1583
1584         return strbuf_detach(&buf, NULL);
1585 }
1586
1587 void append_remote_object_url(struct strbuf *buf, const char *url,
1588                               const char *hex,
1589                               int only_two_digit_prefix)
1590 {
1591         end_url_with_slash(buf, url);
1592
1593         strbuf_addf(buf, "objects/%.*s/", 2, hex);
1594         if (!only_two_digit_prefix)
1595                 strbuf_addstr(buf, hex + 2);
1596 }
1597
1598 char *get_remote_object_url(const char *url, const char *hex,
1599                             int only_two_digit_prefix)
1600 {
1601         struct strbuf buf = STRBUF_INIT;
1602         append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
1603         return strbuf_detach(&buf, NULL);
1604 }
1605
1606 void normalize_curl_result(CURLcode *result, long http_code,
1607                            char *errorstr, size_t errorlen)
1608 {
1609         /*
1610          * If we see a failing http code with CURLE_OK, we have turned off
1611          * FAILONERROR (to keep the server's custom error response), and should
1612          * translate the code into failure here.
1613          *
1614          * Likewise, if we see a redirect (30x code), that means we turned off
1615          * redirect-following, and we should treat the result as an error.
1616          */
1617         if (*result == CURLE_OK && http_code >= 300) {
1618                 *result = CURLE_HTTP_RETURNED_ERROR;
1619                 /*
1620                  * Normally curl will already have put the "reason phrase"
1621                  * from the server into curl_errorstr; unfortunately without
1622                  * FAILONERROR it is lost, so we can give only the numeric
1623                  * status code.
1624                  */
1625                 xsnprintf(errorstr, errorlen,
1626                           "The requested URL returned error: %ld",
1627                           http_code);
1628         }
1629 }
1630
1631 static int handle_curl_result(struct slot_results *results)
1632 {
1633         normalize_curl_result(&results->curl_result, results->http_code,
1634                               curl_errorstr, sizeof(curl_errorstr));
1635
1636         if (results->curl_result == CURLE_OK) {
1637                 credential_approve(&http_auth);
1638                 if (proxy_auth.password)
1639                         credential_approve(&proxy_auth);
1640                 return HTTP_OK;
1641         } else if (missing_target(results))
1642                 return HTTP_MISSING_TARGET;
1643         else if (results->http_code == 401) {
1644 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
1645                 http_auth_methods &= ~CURLAUTH_GSSNEGOTIATE;
1646                 if (results->auth_avail) {
1647                         http_auth_methods &= results->auth_avail;
1648                         http_auth_methods_restricted = 1;
1649                         return HTTP_REAUTH;
1650                 }
1651 #endif
1652                 if (http_auth.username && http_auth.password) {
1653                         credential_reject(&http_auth);
1654                         return HTTP_NOAUTH;
1655                 } else {
1656                         return HTTP_REAUTH;
1657                 }
1658         } else {
1659                 if (results->http_connectcode == 407)
1660                         credential_reject(&proxy_auth);
1661 #if LIBCURL_VERSION_NUM >= 0x070c00
1662                 if (!curl_errorstr[0])
1663                         strlcpy(curl_errorstr,
1664                                 curl_easy_strerror(results->curl_result),
1665                                 sizeof(curl_errorstr));
1666 #endif
1667                 return HTTP_ERROR;
1668         }
1669 }
1670
1671 int run_one_slot(struct active_request_slot *slot,
1672                  struct slot_results *results)
1673 {
1674         slot->results = results;
1675         if (!start_active_slot(slot)) {
1676                 xsnprintf(curl_errorstr, sizeof(curl_errorstr),
1677                           "failed to start HTTP request");
1678                 return HTTP_START_FAILED;
1679         }
1680
1681         run_active_slot(slot);
1682         return handle_curl_result(results);
1683 }
1684
1685 struct curl_slist *http_copy_default_headers(void)
1686 {
1687         struct curl_slist *headers = NULL;
1688         const struct string_list_item *item;
1689
1690         for_each_string_list_item(item, &extra_http_headers)
1691                 headers = curl_slist_append(headers, item->string);
1692
1693         return headers;
1694 }
1695
1696 static CURLcode curlinfo_strbuf(CURL *curl, CURLINFO info, struct strbuf *buf)
1697 {
1698         char *ptr;
1699         CURLcode ret;
1700
1701         strbuf_reset(buf);
1702         ret = curl_easy_getinfo(curl, info, &ptr);
1703         if (!ret && ptr)
1704                 strbuf_addstr(buf, ptr);
1705         return ret;
1706 }
1707
1708 /*
1709  * Check for and extract a content-type parameter. "raw"
1710  * should be positioned at the start of the potential
1711  * parameter, with any whitespace already removed.
1712  *
1713  * "name" is the name of the parameter. The value is appended
1714  * to "out".
1715  */
1716 static int extract_param(const char *raw, const char *name,
1717                          struct strbuf *out)
1718 {
1719         size_t len = strlen(name);
1720
1721         if (strncasecmp(raw, name, len))
1722                 return -1;
1723         raw += len;
1724
1725         if (*raw != '=')
1726                 return -1;
1727         raw++;
1728
1729         while (*raw && !isspace(*raw) && *raw != ';')
1730                 strbuf_addch(out, *raw++);
1731         return 0;
1732 }
1733
1734 /*
1735  * Extract a normalized version of the content type, with any
1736  * spaces suppressed, all letters lowercased, and no trailing ";"
1737  * or parameters.
1738  *
1739  * Note that we will silently remove even invalid whitespace. For
1740  * example, "text / plain" is specifically forbidden by RFC 2616,
1741  * but "text/plain" is the only reasonable output, and this keeps
1742  * our code simple.
1743  *
1744  * If the "charset" argument is not NULL, store the value of any
1745  * charset parameter there.
1746  *
1747  * Example:
1748  *   "TEXT/PLAIN; charset=utf-8" -> "text/plain", "utf-8"
1749  *   "text / plain" -> "text/plain"
1750  */
1751 static void extract_content_type(struct strbuf *raw, struct strbuf *type,
1752                                  struct strbuf *charset)
1753 {
1754         const char *p;
1755
1756         strbuf_reset(type);
1757         strbuf_grow(type, raw->len);
1758         for (p = raw->buf; *p; p++) {
1759                 if (isspace(*p))
1760                         continue;
1761                 if (*p == ';') {
1762                         p++;
1763                         break;
1764                 }
1765                 strbuf_addch(type, tolower(*p));
1766         }
1767
1768         if (!charset)
1769                 return;
1770
1771         strbuf_reset(charset);
1772         while (*p) {
1773                 while (isspace(*p) || *p == ';')
1774                         p++;
1775                 if (!extract_param(p, "charset", charset))
1776                         return;
1777                 while (*p && !isspace(*p))
1778                         p++;
1779         }
1780
1781         if (!charset->len && starts_with(type->buf, "text/"))
1782                 strbuf_addstr(charset, "ISO-8859-1");
1783 }
1784
1785 static void write_accept_language(struct strbuf *buf)
1786 {
1787         /*
1788          * MAX_DECIMAL_PLACES must not be larger than 3. If it is larger than
1789          * that, q-value will be smaller than 0.001, the minimum q-value the
1790          * HTTP specification allows. See
1791          * http://tools.ietf.org/html/rfc7231#section-5.3.1 for q-value.
1792          */
1793         const int MAX_DECIMAL_PLACES = 3;
1794         const int MAX_LANGUAGE_TAGS = 1000;
1795         const int MAX_ACCEPT_LANGUAGE_HEADER_SIZE = 4000;
1796         char **language_tags = NULL;
1797         int num_langs = 0;
1798         const char *s = get_preferred_languages();
1799         int i;
1800         struct strbuf tag = STRBUF_INIT;
1801
1802         /* Don't add Accept-Language header if no language is preferred. */
1803         if (!s)
1804                 return;
1805
1806         /*
1807          * Split the colon-separated string of preferred languages into
1808          * language_tags array.
1809          */
1810         do {
1811                 /* collect language tag */
1812                 for (; *s && (isalnum(*s) || *s == '_'); s++)
1813                         strbuf_addch(&tag, *s == '_' ? '-' : *s);
1814
1815                 /* skip .codeset, @modifier and any other unnecessary parts */
1816                 while (*s && *s != ':')
1817                         s++;
1818
1819                 if (tag.len) {
1820                         num_langs++;
1821                         REALLOC_ARRAY(language_tags, num_langs);
1822                         language_tags[num_langs - 1] = strbuf_detach(&tag, NULL);
1823                         if (num_langs >= MAX_LANGUAGE_TAGS - 1) /* -1 for '*' */
1824                                 break;
1825                 }
1826         } while (*s++);
1827
1828         /* write Accept-Language header into buf */
1829         if (num_langs) {
1830                 int last_buf_len = 0;
1831                 int max_q;
1832                 int decimal_places;
1833                 char q_format[32];
1834
1835                 /* add '*' */
1836                 REALLOC_ARRAY(language_tags, num_langs + 1);
1837                 language_tags[num_langs++] = "*"; /* it's OK; this won't be freed */
1838
1839                 /* compute decimal_places */
1840                 for (max_q = 1, decimal_places = 0;
1841                      max_q < num_langs && decimal_places <= MAX_DECIMAL_PLACES;
1842                      decimal_places++, max_q *= 10)
1843                         ;
1844
1845                 xsnprintf(q_format, sizeof(q_format), ";q=0.%%0%dd", decimal_places);
1846
1847                 strbuf_addstr(buf, "Accept-Language: ");
1848
1849                 for (i = 0; i < num_langs; i++) {
1850                         if (i > 0)
1851                                 strbuf_addstr(buf, ", ");
1852
1853                         strbuf_addstr(buf, language_tags[i]);
1854
1855                         if (i > 0)
1856                                 strbuf_addf(buf, q_format, max_q - i);
1857
1858                         if (buf->len > MAX_ACCEPT_LANGUAGE_HEADER_SIZE) {
1859                                 strbuf_remove(buf, last_buf_len, buf->len - last_buf_len);
1860                                 break;
1861                         }
1862
1863                         last_buf_len = buf->len;
1864                 }
1865         }
1866
1867         /* free language tags -- last one is a static '*' */
1868         for (i = 0; i < num_langs - 1; i++)
1869                 free(language_tags[i]);
1870         free(language_tags);
1871 }
1872
1873 /*
1874  * Get an Accept-Language header which indicates user's preferred languages.
1875  *
1876  * Examples:
1877  *   LANGUAGE= -> ""
1878  *   LANGUAGE=ko:en -> "Accept-Language: ko, en; q=0.9, *; q=0.1"
1879  *   LANGUAGE=ko_KR.UTF-8:sr@latin -> "Accept-Language: ko-KR, sr; q=0.9, *; q=0.1"
1880  *   LANGUAGE=ko LANG=en_US.UTF-8 -> "Accept-Language: ko, *; q=0.1"
1881  *   LANGUAGE= LANG=en_US.UTF-8 -> "Accept-Language: en-US, *; q=0.1"
1882  *   LANGUAGE= LANG=C -> ""
1883  */
1884 static const char *get_accept_language(void)
1885 {
1886         if (!cached_accept_language) {
1887                 struct strbuf buf = STRBUF_INIT;
1888                 write_accept_language(&buf);
1889                 if (buf.len > 0)
1890                         cached_accept_language = strbuf_detach(&buf, NULL);
1891         }
1892
1893         return cached_accept_language;
1894 }
1895
1896 static void http_opt_request_remainder(CURL *curl, off_t pos)
1897 {
1898         char buf[128];
1899         xsnprintf(buf, sizeof(buf), "%"PRIuMAX"-", (uintmax_t)pos);
1900         curl_easy_setopt(curl, CURLOPT_RANGE, buf);
1901 }
1902
1903 /* http_request() targets */
1904 #define HTTP_REQUEST_STRBUF     0
1905 #define HTTP_REQUEST_FILE       1
1906
1907 static int http_request(const char *url,
1908                         void *result, int target,
1909                         const struct http_get_options *options)
1910 {
1911         struct active_request_slot *slot;
1912         struct slot_results results;
1913         struct curl_slist *headers = http_copy_default_headers();
1914         struct strbuf buf = STRBUF_INIT;
1915         const char *accept_language;
1916         int ret;
1917
1918         slot = get_active_slot();
1919         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1920
1921         if (result == NULL) {
1922                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
1923         } else {
1924                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
1925                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
1926
1927                 if (target == HTTP_REQUEST_FILE) {
1928                         off_t posn = ftello(result);
1929                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1930                                          fwrite);
1931                         if (posn > 0)
1932                                 http_opt_request_remainder(slot->curl, posn);
1933                 } else
1934                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1935                                          fwrite_buffer);
1936         }
1937
1938         accept_language = get_accept_language();
1939
1940         if (accept_language)
1941                 headers = curl_slist_append(headers, accept_language);
1942
1943         strbuf_addstr(&buf, "Pragma:");
1944         if (options && options->no_cache)
1945                 strbuf_addstr(&buf, " no-cache");
1946         if (options && options->initial_request &&
1947             http_follow_config == HTTP_FOLLOW_INITIAL)
1948                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 1);
1949
1950         headers = curl_slist_append(headers, buf.buf);
1951
1952         /* Add additional headers here */
1953         if (options && options->extra_headers) {
1954                 const struct string_list_item *item;
1955                 for_each_string_list_item(item, options->extra_headers) {
1956                         headers = curl_slist_append(headers, item->string);
1957                 }
1958         }
1959
1960         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
1961         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1962         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "");
1963         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1964
1965         ret = run_one_slot(slot, &results);
1966
1967         if (options && options->content_type) {
1968                 struct strbuf raw = STRBUF_INIT;
1969                 curlinfo_strbuf(slot->curl, CURLINFO_CONTENT_TYPE, &raw);
1970                 extract_content_type(&raw, options->content_type,
1971                                      options->charset);
1972                 strbuf_release(&raw);
1973         }
1974
1975         if (options && options->effective_url)
1976                 curlinfo_strbuf(slot->curl, CURLINFO_EFFECTIVE_URL,
1977                                 options->effective_url);
1978
1979         curl_slist_free_all(headers);
1980         strbuf_release(&buf);
1981
1982         return ret;
1983 }
1984
1985 /*
1986  * Update the "base" url to a more appropriate value, as deduced by
1987  * redirects seen when requesting a URL starting with "url".
1988  *
1989  * The "asked" parameter is a URL that we asked curl to access, and must begin
1990  * with "base".
1991  *
1992  * The "got" parameter is the URL that curl reported to us as where we ended
1993  * up.
1994  *
1995  * Returns 1 if we updated the base url, 0 otherwise.
1996  *
1997  * Our basic strategy is to compare "base" and "asked" to find the bits
1998  * specific to our request. We then strip those bits off of "got" to yield the
1999  * new base. So for example, if our base is "http://example.com/foo.git",
2000  * and we ask for "http://example.com/foo.git/info/refs", we might end up
2001  * with "https://other.example.com/foo.git/info/refs". We would want the
2002  * new URL to become "https://other.example.com/foo.git".
2003  *
2004  * Note that this assumes a sane redirect scheme. It's entirely possible
2005  * in the example above to end up at a URL that does not even end in
2006  * "info/refs".  In such a case we die. There's not much we can do, such a
2007  * scheme is unlikely to represent a real git repository, and failing to
2008  * rewrite the base opens options for malicious redirects to do funny things.
2009  */
2010 static int update_url_from_redirect(struct strbuf *base,
2011                                     const char *asked,
2012                                     const struct strbuf *got)
2013 {
2014         const char *tail;
2015         size_t new_len;
2016
2017         if (!strcmp(asked, got->buf))
2018                 return 0;
2019
2020         if (!skip_prefix(asked, base->buf, &tail))
2021                 BUG("update_url_from_redirect: %s is not a superset of %s",
2022                     asked, base->buf);
2023
2024         new_len = got->len;
2025         if (!strip_suffix_mem(got->buf, &new_len, tail))
2026                 die(_("unable to update url base from redirection:\n"
2027                       "  asked for: %s\n"
2028                       "   redirect: %s"),
2029                     asked, got->buf);
2030
2031         strbuf_reset(base);
2032         strbuf_add(base, got->buf, new_len);
2033
2034         return 1;
2035 }
2036
2037 static int http_request_reauth(const char *url,
2038                                void *result, int target,
2039                                struct http_get_options *options)
2040 {
2041         int ret = http_request(url, result, target, options);
2042
2043         if (ret != HTTP_OK && ret != HTTP_REAUTH)
2044                 return ret;
2045
2046         if (options && options->effective_url && options->base_url) {
2047                 if (update_url_from_redirect(options->base_url,
2048                                              url, options->effective_url)) {
2049                         credential_from_url(&http_auth, options->base_url->buf);
2050                         url = options->effective_url->buf;
2051                 }
2052         }
2053
2054         if (ret != HTTP_REAUTH)
2055                 return ret;
2056
2057         /*
2058          * The previous request may have put cruft into our output stream; we
2059          * should clear it out before making our next request.
2060          */
2061         switch (target) {
2062         case HTTP_REQUEST_STRBUF:
2063                 strbuf_reset(result);
2064                 break;
2065         case HTTP_REQUEST_FILE:
2066                 if (fflush(result)) {
2067                         error_errno("unable to flush a file");
2068                         return HTTP_START_FAILED;
2069                 }
2070                 rewind(result);
2071                 if (ftruncate(fileno(result), 0) < 0) {
2072                         error_errno("unable to truncate a file");
2073                         return HTTP_START_FAILED;
2074                 }
2075                 break;
2076         default:
2077                 BUG("Unknown http_request target");
2078         }
2079
2080         credential_fill(&http_auth);
2081
2082         return http_request(url, result, target, options);
2083 }
2084
2085 int http_get_strbuf(const char *url,
2086                     struct strbuf *result,
2087                     struct http_get_options *options)
2088 {
2089         return http_request_reauth(url, result, HTTP_REQUEST_STRBUF, options);
2090 }
2091
2092 /*
2093  * Downloads a URL and stores the result in the given file.
2094  *
2095  * If a previous interrupted download is detected (i.e. a previous temporary
2096  * file is still around) the download is resumed.
2097  */
2098 static int http_get_file(const char *url, const char *filename,
2099                          struct http_get_options *options)
2100 {
2101         int ret;
2102         struct strbuf tmpfile = STRBUF_INIT;
2103         FILE *result;
2104
2105         strbuf_addf(&tmpfile, "%s.temp", filename);
2106         result = fopen(tmpfile.buf, "a");
2107         if (!result) {
2108                 error("Unable to open local file %s", tmpfile.buf);
2109                 ret = HTTP_ERROR;
2110                 goto cleanup;
2111         }
2112
2113         ret = http_request_reauth(url, result, HTTP_REQUEST_FILE, options);
2114         fclose(result);
2115
2116         if (ret == HTTP_OK && finalize_object_file(tmpfile.buf, filename))
2117                 ret = HTTP_ERROR;
2118 cleanup:
2119         strbuf_release(&tmpfile);
2120         return ret;
2121 }
2122
2123 int http_fetch_ref(const char *base, struct ref *ref)
2124 {
2125         struct http_get_options options = {0};
2126         char *url;
2127         struct strbuf buffer = STRBUF_INIT;
2128         int ret = -1;
2129
2130         options.no_cache = 1;
2131
2132         url = quote_ref_url(base, ref->name);
2133         if (http_get_strbuf(url, &buffer, &options) == HTTP_OK) {
2134                 strbuf_rtrim(&buffer);
2135                 if (buffer.len == the_hash_algo->hexsz)
2136                         ret = get_oid_hex(buffer.buf, &ref->old_oid);
2137                 else if (starts_with(buffer.buf, "ref: ")) {
2138                         ref->symref = xstrdup(buffer.buf + 5);
2139                         ret = 0;
2140                 }
2141         }
2142
2143         strbuf_release(&buffer);
2144         free(url);
2145         return ret;
2146 }
2147
2148 /* Helpers for fetching packs */
2149 static char *fetch_pack_index(unsigned char *hash, const char *base_url)
2150 {
2151         char *url, *tmp;
2152         struct strbuf buf = STRBUF_INIT;
2153
2154         if (http_is_verbose)
2155                 fprintf(stderr, "Getting index for pack %s\n", hash_to_hex(hash));
2156
2157         end_url_with_slash(&buf, base_url);
2158         strbuf_addf(&buf, "objects/pack/pack-%s.idx", hash_to_hex(hash));
2159         url = strbuf_detach(&buf, NULL);
2160
2161         strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(hash));
2162         tmp = strbuf_detach(&buf, NULL);
2163
2164         if (http_get_file(url, tmp, NULL) != HTTP_OK) {
2165                 error("Unable to get pack index %s", url);
2166                 FREE_AND_NULL(tmp);
2167         }
2168
2169         free(url);
2170         return tmp;
2171 }
2172
2173 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
2174         unsigned char *sha1, const char *base_url)
2175 {
2176         struct packed_git *new_pack;
2177         char *tmp_idx = NULL;
2178         int ret;
2179
2180         if (has_pack_index(sha1)) {
2181                 new_pack = parse_pack_index(sha1, sha1_pack_index_name(sha1));
2182                 if (!new_pack)
2183                         return -1; /* parse_pack_index() already issued error message */
2184                 goto add_pack;
2185         }
2186
2187         tmp_idx = fetch_pack_index(sha1, base_url);
2188         if (!tmp_idx)
2189                 return -1;
2190
2191         new_pack = parse_pack_index(sha1, tmp_idx);
2192         if (!new_pack) {
2193                 unlink(tmp_idx);
2194                 free(tmp_idx);
2195
2196                 return -1; /* parse_pack_index() already issued error message */
2197         }
2198
2199         ret = verify_pack_index(new_pack);
2200         if (!ret) {
2201                 close_pack_index(new_pack);
2202                 ret = finalize_object_file(tmp_idx, sha1_pack_index_name(sha1));
2203         }
2204         free(tmp_idx);
2205         if (ret)
2206                 return -1;
2207
2208 add_pack:
2209         new_pack->next = *packs_head;
2210         *packs_head = new_pack;
2211         return 0;
2212 }
2213
2214 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
2215 {
2216         struct http_get_options options = {0};
2217         int ret = 0;
2218         char *url;
2219         const char *data;
2220         struct strbuf buf = STRBUF_INIT;
2221         struct object_id oid;
2222
2223         end_url_with_slash(&buf, base_url);
2224         strbuf_addstr(&buf, "objects/info/packs");
2225         url = strbuf_detach(&buf, NULL);
2226
2227         options.no_cache = 1;
2228         ret = http_get_strbuf(url, &buf, &options);
2229         if (ret != HTTP_OK)
2230                 goto cleanup;
2231
2232         data = buf.buf;
2233         while (*data) {
2234                 if (skip_prefix(data, "P pack-", &data) &&
2235                     !parse_oid_hex(data, &oid, &data) &&
2236                     skip_prefix(data, ".pack", &data) &&
2237                     (*data == '\n' || *data == '\0')) {
2238                         fetch_and_setup_pack_index(packs_head, oid.hash, base_url);
2239                 } else {
2240                         data = strchrnul(data, '\n');
2241                 }
2242                 if (*data)
2243                         data++; /* skip past newline */
2244         }
2245
2246 cleanup:
2247         free(url);
2248         return ret;
2249 }
2250
2251 void release_http_pack_request(struct http_pack_request *preq)
2252 {
2253         if (preq->packfile != NULL) {
2254                 fclose(preq->packfile);
2255                 preq->packfile = NULL;
2256         }
2257         preq->slot = NULL;
2258         strbuf_release(&preq->tmpfile);
2259         free(preq->url);
2260         free(preq);
2261 }
2262
2263 static const char *default_index_pack_args[] =
2264         {"index-pack", "--stdin", NULL};
2265
2266 int finish_http_pack_request(struct http_pack_request *preq)
2267 {
2268         struct child_process ip = CHILD_PROCESS_INIT;
2269         int tmpfile_fd;
2270         int ret = 0;
2271
2272         fclose(preq->packfile);
2273         preq->packfile = NULL;
2274
2275         tmpfile_fd = xopen(preq->tmpfile.buf, O_RDONLY);
2276
2277         ip.git_cmd = 1;
2278         ip.in = tmpfile_fd;
2279         ip.argv = preq->index_pack_args ? preq->index_pack_args
2280                                         : default_index_pack_args;
2281
2282         if (preq->preserve_index_pack_stdout)
2283                 ip.out = 0;
2284         else
2285                 ip.no_stdout = 1;
2286
2287         if (run_command(&ip)) {
2288                 ret = -1;
2289                 goto cleanup;
2290         }
2291
2292 cleanup:
2293         close(tmpfile_fd);
2294         unlink(preq->tmpfile.buf);
2295         return ret;
2296 }
2297
2298 void http_install_packfile(struct packed_git *p,
2299                            struct packed_git **list_to_remove_from)
2300 {
2301         struct packed_git **lst = list_to_remove_from;
2302
2303         while (*lst != p)
2304                 lst = &((*lst)->next);
2305         *lst = (*lst)->next;
2306
2307         install_packed_git(the_repository, p);
2308 }
2309
2310 struct http_pack_request *new_http_pack_request(
2311         const unsigned char *packed_git_hash, const char *base_url) {
2312
2313         struct strbuf buf = STRBUF_INIT;
2314
2315         end_url_with_slash(&buf, base_url);
2316         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
2317                 hash_to_hex(packed_git_hash));
2318         return new_direct_http_pack_request(packed_git_hash,
2319                                             strbuf_detach(&buf, NULL));
2320 }
2321
2322 struct http_pack_request *new_direct_http_pack_request(
2323         const unsigned char *packed_git_hash, char *url)
2324 {
2325         off_t prev_posn = 0;
2326         struct http_pack_request *preq;
2327
2328         CALLOC_ARRAY(preq, 1);
2329         strbuf_init(&preq->tmpfile, 0);
2330
2331         preq->url = url;
2332
2333         strbuf_addf(&preq->tmpfile, "%s.temp", sha1_pack_name(packed_git_hash));
2334         preq->packfile = fopen(preq->tmpfile.buf, "a");
2335         if (!preq->packfile) {
2336                 error("Unable to open local file %s for pack",
2337                       preq->tmpfile.buf);
2338                 goto abort;
2339         }
2340
2341         preq->slot = get_active_slot();
2342         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
2343         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
2344         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
2345         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
2346                 no_pragma_header);
2347
2348         /*
2349          * If there is data present from a previous transfer attempt,
2350          * resume where it left off
2351          */
2352         prev_posn = ftello(preq->packfile);
2353         if (prev_posn>0) {
2354                 if (http_is_verbose)
2355                         fprintf(stderr,
2356                                 "Resuming fetch of pack %s at byte %"PRIuMAX"\n",
2357                                 hash_to_hex(packed_git_hash),
2358                                 (uintmax_t)prev_posn);
2359                 http_opt_request_remainder(preq->slot->curl, prev_posn);
2360         }
2361
2362         return preq;
2363
2364 abort:
2365         strbuf_release(&preq->tmpfile);
2366         free(preq->url);
2367         free(preq);
2368         return NULL;
2369 }
2370
2371 /* Helpers for fetching objects (loose) */
2372 static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
2373                                void *data)
2374 {
2375         unsigned char expn[4096];
2376         size_t size = eltsize * nmemb;
2377         int posn = 0;
2378         struct http_object_request *freq = data;
2379         struct active_request_slot *slot = freq->slot;
2380
2381         if (slot) {
2382                 CURLcode c = curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE,
2383                                                 &slot->http_code);
2384                 if (c != CURLE_OK)
2385                         BUG("curl_easy_getinfo for HTTP code failed: %s",
2386                                 curl_easy_strerror(c));
2387                 if (slot->http_code >= 300)
2388                         return nmemb;
2389         }
2390
2391         do {
2392                 ssize_t retval = xwrite(freq->localfile,
2393                                         (char *) ptr + posn, size - posn);
2394                 if (retval < 0)
2395                         return posn / eltsize;
2396                 posn += retval;
2397         } while (posn < size);
2398
2399         freq->stream.avail_in = size;
2400         freq->stream.next_in = (void *)ptr;
2401         do {
2402                 freq->stream.next_out = expn;
2403                 freq->stream.avail_out = sizeof(expn);
2404                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
2405                 the_hash_algo->update_fn(&freq->c, expn,
2406                                          sizeof(expn) - freq->stream.avail_out);
2407         } while (freq->stream.avail_in && freq->zret == Z_OK);
2408         return nmemb;
2409 }
2410
2411 struct http_object_request *new_http_object_request(const char *base_url,
2412                                                     const struct object_id *oid)
2413 {
2414         char *hex = oid_to_hex(oid);
2415         struct strbuf filename = STRBUF_INIT;
2416         struct strbuf prevfile = STRBUF_INIT;
2417         int prevlocal;
2418         char prev_buf[PREV_BUF_SIZE];
2419         ssize_t prev_read = 0;
2420         off_t prev_posn = 0;
2421         struct http_object_request *freq;
2422
2423         CALLOC_ARRAY(freq, 1);
2424         strbuf_init(&freq->tmpfile, 0);
2425         oidcpy(&freq->oid, oid);
2426         freq->localfile = -1;
2427
2428         loose_object_path(the_repository, &filename, oid);
2429         strbuf_addf(&freq->tmpfile, "%s.temp", filename.buf);
2430
2431         strbuf_addf(&prevfile, "%s.prev", filename.buf);
2432         unlink_or_warn(prevfile.buf);
2433         rename(freq->tmpfile.buf, prevfile.buf);
2434         unlink_or_warn(freq->tmpfile.buf);
2435         strbuf_release(&filename);
2436
2437         if (freq->localfile != -1)
2438                 error("fd leakage in start: %d", freq->localfile);
2439         freq->localfile = open(freq->tmpfile.buf,
2440                                O_WRONLY | O_CREAT | O_EXCL, 0666);
2441         /*
2442          * This could have failed due to the "lazy directory creation";
2443          * try to mkdir the last path component.
2444          */
2445         if (freq->localfile < 0 && errno == ENOENT) {
2446                 char *dir = strrchr(freq->tmpfile.buf, '/');
2447                 if (dir) {
2448                         *dir = 0;
2449                         mkdir(freq->tmpfile.buf, 0777);
2450                         *dir = '/';
2451                 }
2452                 freq->localfile = open(freq->tmpfile.buf,
2453                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
2454         }
2455
2456         if (freq->localfile < 0) {
2457                 error_errno("Couldn't create temporary file %s",
2458                             freq->tmpfile.buf);
2459                 goto abort;
2460         }
2461
2462         git_inflate_init(&freq->stream);
2463
2464         the_hash_algo->init_fn(&freq->c);
2465
2466         freq->url = get_remote_object_url(base_url, hex, 0);
2467
2468         /*
2469          * If a previous temp file is present, process what was already
2470          * fetched.
2471          */
2472         prevlocal = open(prevfile.buf, O_RDONLY);
2473         if (prevlocal != -1) {
2474                 do {
2475                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
2476                         if (prev_read>0) {
2477                                 if (fwrite_sha1_file(prev_buf,
2478                                                      1,
2479                                                      prev_read,
2480                                                      freq) == prev_read) {
2481                                         prev_posn += prev_read;
2482                                 } else {
2483                                         prev_read = -1;
2484                                 }
2485                         }
2486                 } while (prev_read > 0);
2487                 close(prevlocal);
2488         }
2489         unlink_or_warn(prevfile.buf);
2490         strbuf_release(&prevfile);
2491
2492         /*
2493          * Reset inflate/SHA1 if there was an error reading the previous temp
2494          * file; also rewind to the beginning of the local file.
2495          */
2496         if (prev_read == -1) {
2497                 memset(&freq->stream, 0, sizeof(freq->stream));
2498                 git_inflate_init(&freq->stream);
2499                 the_hash_algo->init_fn(&freq->c);
2500                 if (prev_posn>0) {
2501                         prev_posn = 0;
2502                         lseek(freq->localfile, 0, SEEK_SET);
2503                         if (ftruncate(freq->localfile, 0) < 0) {
2504                                 error_errno("Couldn't truncate temporary file %s",
2505                                             freq->tmpfile.buf);
2506                                 goto abort;
2507                         }
2508                 }
2509         }
2510
2511         freq->slot = get_active_slot();
2512
2513         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
2514         curl_easy_setopt(freq->slot->curl, CURLOPT_FAILONERROR, 0);
2515         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
2516         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
2517         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
2518         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
2519
2520         /*
2521          * If we have successfully processed data from a previous fetch
2522          * attempt, only fetch the data we don't already have.
2523          */
2524         if (prev_posn>0) {
2525                 if (http_is_verbose)
2526                         fprintf(stderr,
2527                                 "Resuming fetch of object %s at byte %"PRIuMAX"\n",
2528                                 hex, (uintmax_t)prev_posn);
2529                 http_opt_request_remainder(freq->slot->curl, prev_posn);
2530         }
2531
2532         return freq;
2533
2534 abort:
2535         strbuf_release(&prevfile);
2536         free(freq->url);
2537         free(freq);
2538         return NULL;
2539 }
2540
2541 void process_http_object_request(struct http_object_request *freq)
2542 {
2543         if (freq->slot == NULL)
2544                 return;
2545         freq->curl_result = freq->slot->curl_result;
2546         freq->http_code = freq->slot->http_code;
2547         freq->slot = NULL;
2548 }
2549
2550 int finish_http_object_request(struct http_object_request *freq)
2551 {
2552         struct stat st;
2553         struct strbuf filename = STRBUF_INIT;
2554
2555         close(freq->localfile);
2556         freq->localfile = -1;
2557
2558         process_http_object_request(freq);
2559
2560         if (freq->http_code == 416) {
2561                 warning("requested range invalid; we may already have all the data.");
2562         } else if (freq->curl_result != CURLE_OK) {
2563                 if (stat(freq->tmpfile.buf, &st) == 0)
2564                         if (st.st_size == 0)
2565                                 unlink_or_warn(freq->tmpfile.buf);
2566                 return -1;
2567         }
2568
2569         git_inflate_end(&freq->stream);
2570         the_hash_algo->final_fn(freq->real_oid.hash, &freq->c);
2571         if (freq->zret != Z_STREAM_END) {
2572                 unlink_or_warn(freq->tmpfile.buf);
2573                 return -1;
2574         }
2575         if (!oideq(&freq->oid, &freq->real_oid)) {
2576                 unlink_or_warn(freq->tmpfile.buf);
2577                 return -1;
2578         }
2579         loose_object_path(the_repository, &filename, &freq->oid);
2580         freq->rename = finalize_object_file(freq->tmpfile.buf, filename.buf);
2581         strbuf_release(&filename);
2582
2583         return freq->rename;
2584 }
2585
2586 void abort_http_object_request(struct http_object_request *freq)
2587 {
2588         unlink_or_warn(freq->tmpfile.buf);
2589
2590         release_http_object_request(freq);
2591 }
2592
2593 void release_http_object_request(struct http_object_request *freq)
2594 {
2595         if (freq->localfile != -1) {
2596                 close(freq->localfile);
2597                 freq->localfile = -1;
2598         }
2599         FREE_AND_NULL(freq->url);
2600         if (freq->slot != NULL) {
2601                 freq->slot->callback_func = NULL;
2602                 freq->slot->callback_data = NULL;
2603                 release_active_slot(freq->slot);
2604                 freq->slot = NULL;
2605         }
2606         strbuf_release(&freq->tmpfile);
2607 }