uclient-example.c

   1 /*
   2  * uclient - ustream based protocol client library
   3  *
   4  * Copyright (C) 2014 Felix Fietkau <nbd@openwrt.org>
   5  *
   6  * Permission to use, copy, modify, and/or distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18
  19 #include <unistd.h>
  20 #include <stdio.h>
  21 #include <dlfcn.h>
  22 #include <getopt.h>
  23 #include <fcntl.h>
  24
  25 #include <libubox/blobmsg.h>
  26
  27 #include "uclient.h"
  28
  29 #ifdef __APPLE__
  30 #define LIB_EXT "dylib"
  31 #else
  32 #define LIB_EXT "so"
  33 #endif
  34
  35 static struct ustream_ssl_ctx *ssl_ctx;
  36 static const struct ustream_ssl_ops *ssl_ops;
  37 static int quiet = false;
  38 static const char *output_file;
  39 static int output_fd = -1;
  40 static int error_ret;
  41
  42 static int open_output_file(const char *path, bool create)
  43 {
  44         const char *str;
  45         char *filename;
  46         int len;
  47         int flags = O_WRONLY;
  48
  49         if (create)
  50                 flags |= O_CREAT;
  51
  52         if (output_file) {
  53                 if (!strcmp(output_file, "-"))
  54                         return STDOUT_FILENO;
  55
  56                 return open(output_file, flags, 0644);
  57         }
  58
  59         /* Don't automatically overwrite files if the name is derived from the URL */
  60         if (create)
  61                 flags |= O_EXCL;
  62
  63         len = strcspn(path, ";&");
  64         while (len > 0 && path[len - 1] == '/')
  65                 len--;
  66
  67         for (str = path + len - 1; str >= path; str--) {
  68                 if (*str == '/')
  69                         break;
  70         }
  71
  72         str++;
  73         len -= str - path;
  74
  75         if (len > 0) {
  76                 filename = alloca(len + 1);
  77                 strncpy(filename, str, len);
  78                 filename[len] = 0;
  79         } else {
  80                 filename = "index.html";
  81         }
  82
  83         return open(filename, flags, 0644);
  84 }
  85
  86 static void request_done(struct uclient *cl)
  87 {
  88         if (output_fd >= 0) {
  89                 close(output_fd);
  90                 output_fd = -1;
  91         }
  92         uclient_disconnect(cl);
  93         uloop_end();
  94 }
  95
  96 static void example_header_done(struct uclient *cl)
  97 {
  98         static int retries;
  99
 100         struct blob_attr *cur;
 101         int rem;
 102
 103         if (retries < 10 && uclient_http_redirect(cl)) {
 104                 if (!quiet)
 105                         fprintf(stderr, "Redirected to %s on %s\n", cl->url->location, cl->url->host);
 106
 107                 retries++;
 108                 return;
 109         }
 110
 111         retries = 0;
 112         if (!quiet) {
 113                 fprintf(stderr, "Headers (%d): \n", cl->status_code);
 114                 blobmsg_for_each_attr(cur, cl->meta, rem) {
 115                         fprintf(stderr, "%s=%s\n", blobmsg_name(cur), (char *) blobmsg_data(cur));
 116                 }
 117         }
 118
 119         switch (cl->status_code) {
 120         case 204:
 121         case 200:
 122                 output_fd = open_output_file(cl->url->location, true);
 123                 if (output_fd < 0) {
 124                         if (!quiet)
 125                                 perror("Cannot open output file");
 126                         error_ret = 3;
 127                         request_done(cl);
 128                 }
 129                 break;
 130
 131         default:
 132                 request_done(cl);
 133                 error_ret = 8;
 134                 break;
 135         }
 136 }
 137
 138 static void example_read_data(struct uclient *cl)
 139 {
 140         char buf[256];
 141         int len;
 142
 143         if (output_fd < 0)
 144                 return;
 145
 146         while (1) {
 147                 len = uclient_read(cl, buf, sizeof(buf));
 148                 if (!len)
 149                         return;
 150
 151                 write(output_fd, buf, len);
 152         }
 153 }
 154
 155 static void msg_connecting(struct uclient *cl)
 156 {
 157         char addr[INET6_ADDRSTRLEN];
 158         int port;
 159
 160         if (quiet)
 161                 return;
 162
 163         uclient_get_addr(addr, &port, &cl->remote_addr);
 164         fprintf(stderr, "Connecting to %s %s:%d\n", cl->url->host, addr, port);
 165 }
 166
 167 static void init_request(struct uclient *cl)
 168 {
 169         uclient_connect(cl);
 170         msg_connecting(cl);
 171         uclient_http_set_request_type(cl, "GET");
 172         uclient_request(cl);
 173 }
 174
 175 static void example_eof(struct uclient *cl)
 176 {
 177         request_done(cl);
 178 }
 179
 180 static void example_error(struct uclient *cl, int code)
 181 {
 182         if (!quiet)
 183                 fprintf(stderr, "Error %d!\n", code);
 184
 185         request_done(cl);
 186 }
 187
 188 static const struct uclient_cb cb = {
 189         .header_done = example_header_done,
 190         .data_read = example_read_data,
 191         .data_eof = example_eof,
 192         .error = example_error,
 193 };
 194
 195 static int usage(const char *progname)
 196 {
 197         fprintf(stderr,
 198                 "Usage: %s [options] <URL>\n"
 199                 "Options:\n"
 200                 "       -O <file>:                      Redirect output to file (use \"-\" for stdout)\n"
 201                 "\n"
 202                 "HTTPS options:\n"
 203                 "       --ca-certificate=<cert>:        Load CA certificates from file <cert>\n"
 204                 "       --no-check-certificate:         don't validate the server's certificate\n"
 205                 "\n", progname);
 206         return 1;
 207 }
 208
 209
 210 static void init_ustream_ssl(void)
 211 {
 212         void *dlh;
 213
 214         dlh = dlopen("libustream-ssl." LIB_EXT, RTLD_LAZY | RTLD_LOCAL);
 215         if (!dlh)
 216                 return;
 217
 218         ssl_ops = dlsym(dlh, "ustream_ssl_ops");
 219         if (!ssl_ops)
 220                 return;
 221
 222         ssl_ctx = ssl_ops->context_new(false);
 223 }
 224
 225 static int no_ssl(const char *progname)
 226 {
 227         fprintf(stderr, "%s: SSL support not available, please install ustream-ssl\n", progname);
 228         return 1;
 229 }
 230
 231 enum {
 232         L_NO_CHECK_CERTIFICATE,
 233         L_CA_CERTIFICATE,
 234 };
 235
 236 static const struct option longopts[] = {
 237         [L_NO_CHECK_CERTIFICATE] = { "no-check-certificate", no_argument },
 238         [L_CA_CERTIFICATE] = { "ca-certificate", required_argument },
 239         {}
 240 };
 241
 242 int main(int argc, char **argv)
 243 {
 244         const char *progname = argv[0];
 245         struct uclient *cl;
 246         bool verify = true;
 247         int ch;
 248         int longopt_idx = 0;
 249
 250         init_ustream_ssl();
 251
 252         while ((ch = getopt_long(argc, argv, "qO:", longopts, &longopt_idx)) != -1) {
 253                 switch(ch) {
 254                 case 0:
 255                         switch (longopt_idx) {
 256                         case L_NO_CHECK_CERTIFICATE:
 257                                 verify = false;
 258                                 break;
 259                         case L_CA_CERTIFICATE:
 260                                 if (ssl_ctx)
 261                                         ssl_ops->context_add_ca_crt_file(ssl_ctx, optarg);
 262                                 break;
 263                         default:
 264                                 return usage(progname);
 265                         }
 266                         break;
 267                 case 'O':
 268                         output_file = optarg;
 269                         break;
 270                 case 'q':
 271                         quiet = true;
 272                         break;
 273                 default:
 274                         return usage(progname);
 275                 }
 276         }
 277
 278         argv += optind;
 279         argc -= optind;
 280
 281         if (argc != 1)
 282                 return usage(progname);
 283
 284         if (!strncmp(argv[0], "https", 5) && !ssl_ctx)
 285                 return no_ssl(progname);
 286
 287         uloop_init();
 288
 289         cl = uclient_new(argv[0], NULL, &cb);
 290         if (!cl) {
 291                 fprintf(stderr, "Failed to allocate uclient context\n");
 292                 return 1;
 293         }
 294
 295         if (ssl_ctx)
 296                 uclient_http_set_ssl_ctx(cl, ssl_ops, ssl_ctx, verify);
 297
 298         init_request(cl);
 299         uloop_run();
 300         uloop_done();
 301
 302         uclient_free(cl);
 303
 304         if (ssl_ctx)
 305                 ssl_ops->context_free(ssl_ctx);
 306
 307         return error_ret;
 308 }