1/* 2 * lws-minimal-http-client 3 * 4 * Written in 2010-2021 by Andy Green <andy@warmcat.com> 5 * 6 * This file is made available under the Creative Commons CC0 1.0 7 * Universal Public Domain Dedication. 8 * 9 * This demonstrates the a minimal http client using lws. 10 * 11 * It visits https://warmcat.com/ and receives the html page there. You 12 * can dump the page data by changing the #if 0 below. 13 */ 14 15#include <libwebsockets.h> 16#include <string.h> 17#include <signal.h> 18 19static int interrupted, bad = 1, status, conmon; 20#if defined(LWS_WITH_HTTP2) 21static int long_poll; 22#endif 23static struct lws *client_wsi; 24static const char *ba_user, *ba_password; 25 26static const lws_retry_bo_t retry = { 27 .secs_since_valid_ping = 3, 28 .secs_since_valid_hangup = 10, 29}; 30 31#if defined(LWS_WITH_CONMON) 32void 33dump_conmon_data(struct lws *wsi) 34{ 35 const struct addrinfo *ai; 36 struct lws_conmon cm; 37 char ads[48]; 38 39 lws_conmon_wsi_take(wsi, &cm); 40 41 lws_sa46_write_numeric_address(&cm.peer46, ads, sizeof(ads)); 42 lwsl_notice("%s: peer %s, dns: %uus, sockconn: %uus, tls: %uus, txn_resp: %uus\n", 43 __func__, ads, 44 (unsigned int)cm.ciu_dns, 45 (unsigned int)cm.ciu_sockconn, 46 (unsigned int)cm.ciu_tls, 47 (unsigned int)cm.ciu_txn_resp); 48 49 ai = cm.dns_results_copy; 50 while (ai) { 51 lws_sa46_write_numeric_address((lws_sockaddr46 *)ai->ai_addr, ads, sizeof(ads)); 52 lwsl_notice("%s: DNS %s\n", __func__, ads); 53 ai = ai->ai_next; 54 } 55 56 /* 57 * This destroys the DNS list in the lws_conmon that we took 58 * responsibility for when we used lws_conmon_wsi_take() 59 */ 60 61 lws_conmon_release(&cm); 62} 63#endif 64 65static const char *ua = "Mozilla/5.0 (X11; Linux x86_64) " 66 "AppleWebKit/537.36 (KHTML, like Gecko) " 67 "Chrome/51.0.2704.103 Safari/537.36", 68 *acc = "*/*"; 69 70static int 71callback_http(struct lws *wsi, enum lws_callback_reasons reason, 72 void *user, void *in, size_t len) 73{ 74 switch (reason) { 75 76 /* because we are protocols[0] ... */ 77 case LWS_CALLBACK_CLIENT_CONNECTION_ERROR: 78 lwsl_err("CLIENT_CONNECTION_ERROR: %s\n", 79 in ? (char *)in : "(null)"); 80 interrupted = 1; 81 bad = 3; /* connection failed before we could make connection */ 82 lws_cancel_service(lws_get_context(wsi)); 83 84#if defined(LWS_WITH_CONMON) 85 if (conmon) 86 dump_conmon_data(wsi); 87#endif 88 break; 89 90 case LWS_CALLBACK_ESTABLISHED_CLIENT_HTTP: 91 { 92 char buf[128]; 93 94 lws_get_peer_simple(wsi, buf, sizeof(buf)); 95 status = (int)lws_http_client_http_response(wsi); 96 97 lwsl_user("Connected to %s, http response: %d\n", 98 buf, status); 99 } 100#if defined(LWS_WITH_HTTP2) 101 if (long_poll) { 102 lwsl_user("%s: Client entering long poll mode\n", __func__); 103 lws_h2_client_stream_long_poll_rxonly(wsi); 104 } 105#endif 106 107 if (lws_fi_user_wsi_fi(wsi, "user_reject_at_est")) 108 return -1; 109 110 break; 111 112 /* you only need this if you need to do Basic Auth */ 113 case LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER: 114 { 115 unsigned char **p = (unsigned char **)in, *end = (*p) + len; 116 117 if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_USER_AGENT, 118 (unsigned char *)ua, (int)strlen(ua), p, end)) 119 return -1; 120 121 if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_ACCEPT, 122 (unsigned char *)acc, (int)strlen(acc), p, end)) 123 return -1; 124#if defined(LWS_WITH_HTTP_BASIC_AUTH) 125 { 126 char b[128]; 127 128 if (!ba_user || !ba_password) 129 break; 130 131 if (lws_http_basic_auth_gen(ba_user, ba_password, b, sizeof(b))) 132 break; 133 if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_AUTHORIZATION, 134 (unsigned char *)b, (int)strlen(b), p, end)) 135 return -1; 136 } 137#endif 138 break; 139 } 140 141 /* chunks of chunked content, with header removed */ 142 case LWS_CALLBACK_RECEIVE_CLIENT_HTTP_READ: 143 lwsl_user("RECEIVE_CLIENT_HTTP_READ: read %d\n", (int)len); 144#if defined(LWS_WITH_HTTP2) 145 if (long_poll) { 146 char dotstar[128]; 147 lws_strnncpy(dotstar, (const char *)in, len, 148 sizeof(dotstar)); 149 lwsl_notice("long poll rx: %d '%s'\n", (int)len, 150 dotstar); 151 } 152#endif 153#if 0 154 lwsl_hexdump_notice(in, len); 155#endif 156 157 return 0; /* don't passthru */ 158 159 /* uninterpreted http content */ 160 case LWS_CALLBACK_RECEIVE_CLIENT_HTTP: 161 { 162 char buffer[1024 + LWS_PRE]; 163 char *px = buffer + LWS_PRE; 164 int lenx = sizeof(buffer) - LWS_PRE; 165 166 if (lws_fi_user_wsi_fi(wsi, "user_reject_at_rx")) 167 return -1; 168 169 if (lws_http_client_read(wsi, &px, &lenx) < 0) 170 return -1; 171 } 172 return 0; /* don't passthru */ 173 174 case LWS_CALLBACK_COMPLETED_CLIENT_HTTP: 175 lwsl_user("LWS_CALLBACK_COMPLETED_CLIENT_HTTP\n"); 176 interrupted = 1; 177 bad = status != 200; 178 lws_cancel_service(lws_get_context(wsi)); /* abort poll wait */ 179 break; 180 181 case LWS_CALLBACK_CLOSED_CLIENT_HTTP: 182 interrupted = 1; 183 bad = status != 200; 184 lws_cancel_service(lws_get_context(wsi)); /* abort poll wait */ 185#if defined(LWS_WITH_CONMON) 186 if (conmon) 187 dump_conmon_data(wsi); 188#endif 189 break; 190 191 default: 192 break; 193 } 194 195 return lws_callback_http_dummy(wsi, reason, user, in, len); 196} 197 198static const struct lws_protocols protocols[] = { 199 { 200 "http", 201 callback_http, 202 0, 0, 0, NULL, 0 203 }, 204 LWS_PROTOCOL_LIST_TERM 205}; 206 207static void 208sigint_handler(int sig) 209{ 210 interrupted = 1; 211} 212 213struct args { 214 int argc; 215 const char **argv; 216}; 217 218static int 219system_notify_cb(lws_state_manager_t *mgr, lws_state_notify_link_t *link, 220 int current, int target) 221{ 222 struct lws_context *context = mgr->parent; 223 struct lws_client_connect_info i; 224 struct args *a = lws_context_user(context); 225 const char *p; 226 227 if (current != LWS_SYSTATE_OPERATIONAL || target != LWS_SYSTATE_OPERATIONAL) 228 return 0; 229 230 lwsl_info("%s: operational\n", __func__); 231 232 memset(&i, 0, sizeof i); /* otherwise uninitialized garbage */ 233 i.context = context; 234 if (!lws_cmdline_option(a->argc, a->argv, "-n")) { 235 i.ssl_connection = LCCSCF_USE_SSL; 236#if defined(LWS_WITH_HTTP2) 237 /* requires h2 */ 238 if (lws_cmdline_option(a->argc, a->argv, "--long-poll")) { 239 lwsl_user("%s: long poll mode\n", __func__); 240 long_poll = 1; 241 } 242#endif 243 } 244 245 if (lws_cmdline_option(a->argc, a->argv, "-l")) { 246 i.port = 7681; 247 i.address = "localhost"; 248 i.ssl_connection |= LCCSCF_ALLOW_SELFSIGNED; 249 } else { 250 i.port = 443; 251 i.address = "warmcat.com"; 252 } 253 254 if (lws_cmdline_option(a->argc, a->argv, "--nossl")) 255 i.ssl_connection = 0; 256 257 i.ssl_connection |= LCCSCF_H2_QUIRK_OVERFLOWS_TXCR | 258 LCCSCF_ACCEPT_TLS_DOWNGRADE_REDIRECTS | 259 LCCSCF_H2_QUIRK_NGHTTP2_END_STREAM; 260 261 i.alpn = "h2,http/1.1"; 262 if (lws_cmdline_option(a->argc, a->argv, "--h1")) 263 i.alpn = "http/1.1"; 264 265 if (lws_cmdline_option(a->argc, a->argv, "--h2-prior-knowledge")) 266 i.ssl_connection |= LCCSCF_H2_PRIOR_KNOWLEDGE; 267 268 if ((p = lws_cmdline_option(a->argc, a->argv, "-p"))) 269 i.port = atoi(p); 270 271 if ((p = lws_cmdline_option(a->argc, a->argv, "--user"))) 272 ba_user = p; 273 if ((p = lws_cmdline_option(a->argc, a->argv, "--password"))) 274 ba_password = p; 275 276 if (lws_cmdline_option(a->argc, a->argv, "-j")) 277 i.ssl_connection |= LCCSCF_ALLOW_SELFSIGNED; 278 279 if (lws_cmdline_option(a->argc, a->argv, "-k")) 280 i.ssl_connection |= LCCSCF_ALLOW_INSECURE; 281 282 if (lws_cmdline_option(a->argc, a->argv, "-b")) 283 i.ssl_connection |= LCCSCF_CACHE_COOKIES; 284 285 if (lws_cmdline_option(a->argc, a->argv, "-m")) 286 i.ssl_connection |= LCCSCF_SKIP_SERVER_CERT_HOSTNAME_CHECK; 287 288 if (lws_cmdline_option(a->argc, a->argv, "-e")) 289 i.ssl_connection |= LCCSCF_ALLOW_EXPIRED; 290 291 if ((p = lws_cmdline_option(a->argc, a->argv, "-f"))) { 292 i.ssl_connection |= LCCSCF_H2_MANUAL_RXFLOW; 293 i.manual_initial_tx_credit = atoi(p); 294 lwsl_notice("%s: manual peer tx credit %d\n", __func__, 295 i.manual_initial_tx_credit); 296 } 297 298#if defined(LWS_WITH_CONMON) 299 if (lws_cmdline_option(a->argc, a->argv, "--conmon")) { 300 i.ssl_connection |= LCCSCF_CONMON; 301 conmon = 1; 302 } 303#endif 304 305 /* the default validity check is 5m / 5m10s... -v = 3s / 10s */ 306 307 if (lws_cmdline_option(a->argc, a->argv, "-v")) 308 i.retry_and_idle_policy = &retry; 309 310 if ((p = lws_cmdline_option(a->argc, a->argv, "--server"))) 311 i.address = p; 312 313 if ((p = lws_cmdline_option(a->argc, a->argv, "--path"))) 314 i.path = p; 315 else 316 i.path = "/"; 317 318 i.host = i.address; 319 i.origin = i.address; 320 i.method = "GET"; 321 322 i.protocol = protocols[0].name; 323 i.pwsi = &client_wsi; 324 i.fi_wsi_name = "user"; 325 326 if (!lws_client_connect_via_info(&i)) { 327 lwsl_err("Client creation failed\n"); 328 interrupted = 1; 329 bad = 2; /* could not even start client connection */ 330 lws_cancel_service(context); 331 332 return 1; 333 } 334 335 return 0; 336} 337 338int main(int argc, const char **argv) 339{ 340 lws_state_notify_link_t notifier = { { NULL, NULL, NULL }, 341 system_notify_cb, "app" }; 342 lws_state_notify_link_t *na[] = { ¬ifier, NULL }; 343 struct lws_context_creation_info info; 344 struct lws_context *context; 345 int n = 0, expected = 0; 346 struct args args; 347 const char *p; 348 // uint8_t memcert[4096]; 349 350 args.argc = argc; 351 args.argv = argv; 352 353 signal(SIGINT, sigint_handler); 354 355 memset(&info, 0, sizeof info); /* otherwise uninitialized garbage */ 356 lws_cmdline_option_handle_builtin(argc, argv, &info); 357 358 lwsl_user("LWS minimal http client [-d<verbosity>] [-l] [--h1]\n"); 359 360 info.options = LWS_SERVER_OPTION_DO_SSL_GLOBAL_INIT | 361 LWS_SERVER_OPTION_H2_JUST_FIX_WINDOW_UPDATE_OVERFLOW; 362 info.port = CONTEXT_PORT_NO_LISTEN; /* we do not run any server */ 363 info.protocols = protocols; 364 info.user = &args; 365 info.register_notifier_list = na; 366 info.connect_timeout_secs = 30; 367 368#if defined(LWS_WITH_CACHE_NSCOOKIEJAR) 369 info.http_nsc_filepath = "./cookies.txt"; 370 if ((p = lws_cmdline_option(argc, argv, "-c"))) 371 info.http_nsc_filepath = p; 372#endif 373 374 /* 375 * since we know this lws context is only ever going to be used with 376 * one client wsis / fds / sockets at a time, let lws know it doesn't 377 * have to use the default allocations for fd tables up to ulimit -n. 378 * It will just allocate for 1 internal and 1 (+ 1 http2 nwsi) that we 379 * will use. 380 */ 381 info.fd_limit_per_thread = 1 + 1 + 1; 382 383#if defined(LWS_WITH_MBEDTLS) || defined(USE_WOLFSSL) 384 /* 385 * OpenSSL uses the system trust store. mbedTLS has to be told which 386 * CA to trust explicitly. 387 */ 388 if (lws_cmdline_option(argc, argv, "-w")) 389 /* option to confirm we are validating against the right cert */ 390 info.client_ssl_ca_filepath = "./wrong.cer"; 391 else 392 info.client_ssl_ca_filepath = "./warmcat.com.cer"; 393#endif 394#if 0 395 n = open("./warmcat.com.cer", O_RDONLY); 396 if (n >= 0) { 397 info.client_ssl_ca_mem_len = read(n, memcert, sizeof(memcert)); 398 info.client_ssl_ca_mem = memcert; 399 close(n); 400 n = 0; 401 memcert[info.client_ssl_ca_mem_len++] = '\0'; 402 } 403#endif 404 context = lws_create_context(&info); 405 if (!context) { 406 lwsl_err("lws init failed\n"); 407 bad = 5; 408 goto bail; 409 } 410 411 while (n >= 0 && !interrupted) 412 n = lws_service(context, 0); 413 414 lws_context_destroy(context); 415 416bail: 417 if ((p = lws_cmdline_option(argc, argv, "--expected-exit"))) 418 expected = atoi(p); 419 420 if (bad == expected) { 421 lwsl_user("Completed: OK (seen expected %d)\n", expected); 422 return 0; 423 } else 424 lwsl_err("Completed: failed: exit %d, expected %d\n", bad, expected); 425 426 return 1; 427} 428