/* Get the key from URL which is expected to specify a http style scheme. On success R_FP has an open stream to read the data. */ gpg_error_t ks_http_fetch (ctrl_t ctrl, const char *url, estream_t *r_fp) { gpg_error_t err; http_session_t session = NULL; http_t http = NULL; int redirects_left = MAX_REDIRECTS; estream_t fp = NULL; char *request_buffer = NULL; err = http_session_new (&session, NULL); if (err) goto leave; http_session_set_log_cb (session, cert_log_cb); *r_fp = NULL; once_more: err = http_open (&http, HTTP_REQ_GET, url, /* httphost */ NULL, /* fixme: AUTH */ NULL, 0, /* fixme: proxy*/ NULL, session, NULL, /*FIXME curl->srvtag*/NULL); if (!err) { fp = http_get_write_ptr (http); /* Avoid caches to get the most recent copy of the key. We set both the Pragma and Cache-Control versions of the header, so we're good with both HTTP 1.0 and 1.1. */ es_fputs ("Pragma: no-cache\r\n" "Cache-Control: no-cache\r\n", fp); http_start_data (http); if (es_ferror (fp)) err = gpg_error_from_syserror (); } if (err) { /* Fixme: After a redirection we show the old host name. */ log_error (_("error connecting to '%s': %s\n"), url, gpg_strerror (err)); goto leave; } /* Wait for the response. */ dirmngr_tick (ctrl); err = http_wait_response (http); if (err) { log_error (_("error reading HTTP response for '%s': %s\n"), url, gpg_strerror (err)); goto leave; } switch (http_get_status_code (http)) { case 200: err = 0; break; /* Success. */ case 301: case 302: case 307: { const char *s = http_get_header (http, "Location"); log_info (_("URL '%s' redirected to '%s' (%u)\n"), url, s?s:"[none]", http_get_status_code (http)); if (s && *s && redirects_left-- ) { xfree (request_buffer); request_buffer = xtrystrdup (s); if (request_buffer) { url = request_buffer; http_close (http, 0); http = NULL; goto once_more; } err = gpg_error_from_syserror (); } else err = gpg_error (GPG_ERR_NO_DATA); log_error (_("too many redirections\n")); } goto leave; default: log_error (_("error accessing '%s': http status %u\n"), url, http_get_status_code (http)); err = gpg_error (GPG_ERR_NO_DATA); goto leave; } fp = http_get_read_ptr (http); if (!fp) { err = gpg_error (GPG_ERR_BUG); goto leave; } /* Return the read stream and close the HTTP context. */ *r_fp = fp; http_close (http, 1); http = NULL; leave: http_close (http, 0); http_session_release (session); xfree (request_buffer); return err; }
/* Send an HTTP request. On success returns an estream object at R_FP. HOSTPORTSTR is only used for diagnostics. If HTTPHOST is not NULL it will be used as HTTP "Host" header. If POST_CB is not NULL a post request is used and that callback is called to allow writing the post data. */ static gpg_error_t send_request (ctrl_t ctrl, const char *request, const char *hostportstr, const char *httphost, unsigned int httpflags, gpg_error_t (*post_cb)(void *, http_t), void *post_cb_value, estream_t *r_fp) { gpg_error_t err; http_session_t session = NULL; http_t http = NULL; int redirects_left = MAX_REDIRECTS; estream_t fp = NULL; char *request_buffer = NULL; *r_fp = NULL; err = http_session_new (&session, NULL); if (err) goto leave; http_session_set_log_cb (session, cert_log_cb); once_more: err = http_open (&http, post_cb? HTTP_REQ_POST : HTTP_REQ_GET, request, httphost, /* fixme: AUTH */ NULL, (httpflags | (opt.honor_http_proxy? HTTP_FLAG_TRY_PROXY:0)), ctrl->http_proxy, session, NULL, /*FIXME curl->srvtag*/NULL); if (!err) { fp = http_get_write_ptr (http); /* Avoid caches to get the most recent copy of the key. We set both the Pragma and Cache-Control versions of the header, so we're good with both HTTP 1.0 and 1.1. */ es_fputs ("Pragma: no-cache\r\n" "Cache-Control: no-cache\r\n", fp); if (post_cb) err = post_cb (post_cb_value, http); if (!err) { http_start_data (http); if (es_ferror (fp)) err = gpg_error_from_syserror (); } } if (err) { /* Fixme: After a redirection we show the old host name. */ log_error (_("error connecting to '%s': %s\n"), hostportstr, gpg_strerror (err)); goto leave; } /* Wait for the response. */ dirmngr_tick (ctrl); err = http_wait_response (http); if (err) { log_error (_("error reading HTTP response for '%s': %s\n"), hostportstr, gpg_strerror (err)); goto leave; } if (http_get_tls_info (http, NULL)) { /* Update the httpflags so that a redirect won't fallback to an unencrypted connection. */ httpflags |= HTTP_FLAG_FORCE_TLS; } switch (http_get_status_code (http)) { case 200: err = 0; break; /* Success. */ case 301: case 302: case 307: { const char *s = http_get_header (http, "Location"); log_info (_("URL '%s' redirected to '%s' (%u)\n"), request, s?s:"[none]", http_get_status_code (http)); if (s && *s && redirects_left-- ) { xfree (request_buffer); request_buffer = xtrystrdup (s); if (request_buffer) { request = request_buffer; http_close (http, 0); http = NULL; goto once_more; } err = gpg_error_from_syserror (); } else err = gpg_error (GPG_ERR_NO_DATA); log_error (_("too many redirections\n")); } goto leave; default: log_error (_("error accessing '%s': http status %u\n"), request, http_get_status_code (http)); err = gpg_error (GPG_ERR_NO_DATA); goto leave; } /* FIXME: We should register a permanent redirection and whether a host has ever used TLS so that future calls will always use TLS. */ fp = http_get_read_ptr (http); if (!fp) { err = gpg_error (GPG_ERR_BUG); goto leave; } /* Return the read stream and close the HTTP context. */ *r_fp = fp; http_close (http, 1); http = NULL; leave: http_close (http, 0); http_session_release (session); xfree (request_buffer); return err; }