1/* 2 * lws-minimal-http-server-custom-headers 3 * 4 * Written in 2010-2019 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 a minimal http server that can produce dynamic http 10 * content as well as static content. 11 * 12 * To keep it simple, it serves the static stuff from the subdirectory 13 * "./mount-origin" of the directory it was started in. 14 * 15 * You can change that by changing mount.origin below. 16 */ 17 18#include <libwebsockets.h> 19#include <string.h> 20#include <signal.h> 21#include <time.h> 22 23static int interrupted; 24 25struct pss { 26 char result[128 + LWS_PRE]; 27 int len; 28}; 29 30/* 31 * This just lets us override LWS_CALLBACK_HTTP handling before passing it 32 * and everything else to the default handler. 33 */ 34 35static int 36callback_http(struct lws *wsi, enum lws_callback_reasons reason, 37 void *user, void *in, size_t len) 38{ 39 uint8_t buf[LWS_PRE + 2048], *start = &buf[LWS_PRE], *p = start, 40 *end = &buf[sizeof(buf) - 1]; 41 struct pss *pss = (struct pss *)user; 42 char value[32], *pr = &pss->result[LWS_PRE]; 43 size_t e = sizeof(pss->result) - LWS_PRE; 44 int n; 45 46 switch (reason) { 47 case LWS_CALLBACK_HTTP: 48 /* 49 * LWS doesn't have the "DNT" header built-in. But we can 50 * query it using the "custom" versions of the header apis. 51 * 52 * You can set your modern browser to issue DNT, look in the 53 * privacy settings of your browser. 54 */ 55 56 pss->len = 0; 57 n = lws_hdr_custom_length(wsi, "dnt:", 4); 58 if (n < 0) 59 pss->len = lws_snprintf(pr, e, 60 "%s: DNT header not found\n", __func__); 61 else { 62 63 pss->len = lws_snprintf(pr, e, 64 "%s: DNT length %d<br>", __func__, n); 65 n = lws_hdr_custom_copy(wsi, value, sizeof(value), "dnt:", 4); 66 if (n < 0) 67 pss->len += lws_snprintf(pr + pss->len, e - (unsigned int)pss->len, 68 "%s: unable to get DNT value\n", __func__); 69 else 70 71 pss->len += lws_snprintf(pr + pss->len , e - (unsigned int)pss->len, 72 "%s: DNT value '%s'\n", __func__, value); 73 } 74 75 lwsl_user("%s\n", pr); 76 77 if (lws_add_http_common_headers(wsi, HTTP_STATUS_OK, 78 "text/html", (lws_filepos_t)pss->len, &p, end)) 79 return 1; 80 81 if (lws_finalize_write_http_header(wsi, start, &p, end)) 82 return 1; 83 84 85 /* write the body separately */ 86 lws_callback_on_writable(wsi); 87 return 0; 88 89 case LWS_CALLBACK_HTTP_WRITEABLE: 90 91 strcpy((char *)start, "hello"); 92 93 if (lws_write(wsi, (uint8_t *)pr, (unsigned int)pss->len, LWS_WRITE_HTTP_FINAL) != pss->len) 94 return 1; 95 96 if (lws_http_transaction_completed(wsi)) 97 return -1; 98 return 0; 99 100 default: 101 break; 102 } 103 104 return lws_callback_http_dummy(wsi, reason, user, in, len); 105} 106 107static struct lws_protocols protocols[] = { 108 { "http", callback_http, sizeof(struct pss), 0, 0, NULL, 0 }, 109 LWS_PROTOCOL_LIST_TERM 110}; 111 112static const struct lws_http_mount mount_dyn = { 113 /* .mount_next */ NULL, /* linked-list "next" */ 114 /* .mountpoint */ "/dyn", /* mountpoint URL */ 115 /* .origin */ NULL, /* protocol */ 116 /* .def */ NULL, 117 /* .protocol */ "http", 118 /* .cgienv */ NULL, 119 /* .extra_mimetypes */ NULL, 120 /* .interpret */ NULL, 121 /* .cgi_timeout */ 0, 122 /* .cache_max_age */ 0, 123 /* .auth_mask */ 0, 124 /* .cache_reusable */ 0, 125 /* .cache_revalidate */ 0, 126 /* .cache_intermediaries */ 0, 127 /* .origin_protocol */ LWSMPRO_CALLBACK, /* dynamic */ 128 /* .mountpoint_len */ 4, /* char count */ 129 /* .basic_auth_login_file */ NULL, 130}; 131 132/* default mount serves the URL space from ./mount-origin */ 133 134static const struct lws_http_mount mount = { 135 /* .mount_next */ &mount_dyn, /* linked-list "next" */ 136 /* .mountpoint */ "/", /* mountpoint URL */ 137 /* .origin */ "./mount-origin", /* serve from dir */ 138 /* .def */ "index.html", /* default filename */ 139 /* .protocol */ NULL, 140 /* .cgienv */ NULL, 141 /* .extra_mimetypes */ NULL, 142 /* .interpret */ NULL, 143 /* .cgi_timeout */ 0, 144 /* .cache_max_age */ 0, 145 /* .auth_mask */ 0, 146 /* .cache_reusable */ 0, 147 /* .cache_revalidate */ 0, 148 /* .cache_intermediaries */ 0, 149 /* .origin_protocol */ LWSMPRO_FILE, /* files in a dir */ 150 /* .mountpoint_len */ 1, /* char count */ 151 /* .basic_auth_login_file */ NULL, 152}; 153 154void sigint_handler(int sig) 155{ 156 interrupted = 1; 157} 158 159int main(int argc, const char **argv) 160{ 161 struct lws_context_creation_info info; 162 struct lws_context *context; 163 const char *p; 164 int n = 0, logs = LLL_USER | LLL_ERR | LLL_WARN | LLL_NOTICE; 165 166 signal(SIGINT, sigint_handler); 167 168 if ((p = lws_cmdline_option(argc, argv, "-d"))) 169 logs = atoi(p); 170 171 lws_set_log_level(logs, NULL); 172 lwsl_user("LWS minimal http server custom headers | visit http://localhost:7681\n"); 173 174 memset(&info, 0, sizeof info); /* otherwise uninitialized garbage */ 175 info.options = LWS_SERVER_OPTION_DO_SSL_GLOBAL_INIT | 176 LWS_SERVER_OPTION_EXPLICIT_VHOSTS | 177 LWS_SERVER_OPTION_HTTP_HEADERS_SECURITY_BEST_PRACTICES_ENFORCE; 178 179 /* for testing ah queue, not useful in real world */ 180 if (lws_cmdline_option(argc, argv, "--ah1")) 181 info.max_http_header_pool = 1; 182 183 context = lws_create_context(&info); 184 if (!context) { 185 lwsl_err("lws init failed\n"); 186 return 1; 187 } 188 189 /* http on 7681 */ 190 191 info.port = 7681; 192 info.protocols = protocols; 193 info.mounts = &mount; 194 info.vhost_name = "http"; 195 196 if (!lws_create_vhost(context, &info)) { 197 lwsl_err("Failed to create tls vhost\n"); 198 goto bail; 199 } 200 201 /* https on 7682 */ 202 203 info.port = 7682; 204 info.error_document_404 = "/404.html"; 205#if defined(LWS_WITH_TLS) 206 info.ssl_cert_filepath = "localhost-100y.cert"; 207 info.ssl_private_key_filepath = "localhost-100y.key"; 208#endif 209 info.vhost_name = "https"; 210 211 if (!lws_create_vhost(context, &info)) { 212 lwsl_err("Failed to create tls vhost\n"); 213 goto bail; 214 } 215 216 while (n >= 0 && !interrupted) 217 n = lws_service(context, 0); 218 219bail: 220 lws_context_destroy(context); 221 222 return 0; 223} 224