uclient-fetch.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 #include "uclient-utils.h"
  29
  30 #ifdef __APPLE__
  31 #define LIB_EXT "dylib"
  32 #else
  33 #define LIB_EXT "so"
  34 #endif
  35
  36 static struct ustream_ssl_ctx *ssl_ctx;
  37 static const struct ustream_ssl_ops *ssl_ops;
  38 static int quiet = false;
  39 static bool verify = true;
  40 static const char *output_file;
  41 static int output_fd = -1;
  42 static int error_ret;
  43
  44 static int open_output_file(const char *path, bool create)
  45 {
  46         char *filename;
  47         int flags = O_WRONLY;
  48         int ret;
  49
  50         if (create)
  51                 flags |= O_CREAT;
  52
  53         if (output_file) {
  54                 if (!strcmp(output_file, "-"))
  55                         return STDOUT_FILENO;
  56
  57                 return open(output_file, flags, 0644);
  58         }
  59
  60         /* Don't automatically overwrite files if the name is derived from the URL */
  61         if (create)
  62                 flags |= O_EXCL;
  63
  64         filename = uclient_get_url_filename(path, "index.html");
  65         ret = open(filename, flags, 0644);
  66         free(filename);
  67
  68         return ret;
  69 }
  70
  71 static void request_done(struct uclient *cl)
  72 {
  73         if (output_fd >= 0 && !output_file) {
  74                 close(output_fd);
  75                 output_fd = -1;
  76         }
  77         uclient_disconnect(cl);
  78         uloop_end();
  79 }
  80
  81 static void header_done_cb(struct uclient *cl)
  82 {
  83         static int retries;
  84
  85         if (retries < 10 && uclient_http_redirect(cl)) {
  86                 if (!quiet)
  87                         fprintf(stderr, "Redirected to %s on %s\n", cl->url->location, cl->url->host);
  88
  89                 retries++;
  90                 return;
  91         }
  92
  93         retries = 0;
  94         switch (cl->status_code) {
  95         case 204:
  96         case 200:
  97                 output_fd = open_output_file(cl->url->location, true);
  98                 if (output_fd < 0) {
  99                         if (!quiet)
 100                                 perror("Cannot open output file");
 101                         error_ret = 3;
 102                         request_done(cl);
 103                 }
 104                 break;
 105
 106         default:
 107                 if (!quiet)
 108                         fprintf(stderr, "HTTP error %d\n", cl->status_code);
 109                 request_done(cl);
 110                 error_ret = 8;
 111                 break;
 112         }
 113 }
 114
 115 static void read_data_cb(struct uclient *cl)
 116 {
 117         char buf[256];
 118         int len;
 119
 120         if (output_fd < 0)
 121                 return;
 122
 123         while (1) {
 124                 len = uclient_read(cl, buf, sizeof(buf));
 125                 if (!len)
 126                         return;
 127
 128                 write(output_fd, buf, len);
 129         }
 130 }
 131
 132 static void msg_connecting(struct uclient *cl)
 133 {
 134         char addr[INET6_ADDRSTRLEN];
 135         int port;
 136
 137         if (quiet)
 138                 return;
 139
 140         uclient_get_addr(addr, &port, &cl->remote_addr);
 141         fprintf(stderr, "Connecting to %s %s:%d\n", cl->url->host, addr, port);
 142 }
 143
 144 static void init_request(struct uclient *cl)
 145 {
 146         uclient_connect(cl);
 147         msg_connecting(cl);
 148         uclient_http_set_request_type(cl, "GET");
 149         uclient_request(cl);
 150 }
 151
 152 static void eof_cb(struct uclient *cl)
 153 {
 154         if (!cl->data_eof) {
 155                 if (!quiet)
 156                         fprintf(stderr, "Connection reset prematurely\n");
 157                 error_ret = 4;
 158         }
 159         request_done(cl);
 160 }
 161
 162 static void handle_uclient_error(struct uclient *cl, int code)
 163 {
 164         const char *type = "Unknown error";
 165         bool ignore = false;
 166
 167         switch(code) {
 168         case UCLIENT_ERROR_CONNECT:
 169                 type = "Connection failed";
 170                 error_ret = 4;
 171                 break;
 172         case UCLIENT_ERROR_SSL_INVALID_CERT:
 173                 type = "Invalid SSL certificate";
 174                 ignore = !verify;
 175                 error_ret = 5;
 176                 break;
 177         case UCLIENT_ERROR_SSL_CN_MISMATCH:
 178                 type = "Server hostname does not match SSL certificate";
 179                 ignore = !verify;
 180                 error_ret = 5;
 181                 break;
 182         default:
 183                 error_ret = 1;
 184                 break;
 185         }
 186
 187         if (!quiet)
 188                 fprintf(stderr, "Connection error: %s%s\n", type, ignore ? " (ignored)" : "");
 189
 190         if (ignore)
 191                 error_ret = 0;
 192         else
 193                 request_done(cl);
 194 }
 195
 196 static const struct uclient_cb cb = {
 197         .header_done = header_done_cb,
 198         .data_read = read_data_cb,
 199         .data_eof = eof_cb,
 200         .error = handle_uclient_error,
 201 };
 202
 203 static int usage(const char *progname)
 204 {
 205         fprintf(stderr,
 206                 "Usage: %s [options] <URL>\n"
 207                 "Options:\n"
 208                 "       -q:                             Turn off status messages\n"
 209                 "       -O <file>:                      Redirect output to file (use \"-\" for stdout)\n"
 210                 "\n"
 211                 "HTTPS options:\n"
 212                 "       --ca-certificate=<cert>:        Load CA certificates from file <cert>\n"
 213                 "       --no-check-certificate:         don't validate the server's certificate\n"
 214                 "\n", progname);
 215         return 1;
 216 }
 217
 218
 219 static void init_ustream_ssl(void)
 220 {
 221         void *dlh;
 222
 223         dlh = dlopen("libustream-ssl." LIB_EXT, RTLD_LAZY | RTLD_LOCAL);
 224         if (!dlh)
 225                 return;
 226
 227         ssl_ops = dlsym(dlh, "ustream_ssl_ops");
 228         if (!ssl_ops)
 229                 return;
 230
 231         ssl_ctx = ssl_ops->context_new(false);
 232 }
 233
 234 static int no_ssl(const char *progname)
 235 {
 236         fprintf(stderr, "%s: SSL support not available, please install ustream-ssl\n", progname);
 237         return 1;
 238 }
 239
 240 enum {
 241         L_NO_CHECK_CERTIFICATE,
 242         L_CA_CERTIFICATE,
 243 };
 244
 245 static const struct option longopts[] = {
 246         [L_NO_CHECK_CERTIFICATE] = { "no-check-certificate", no_argument },
 247         [L_CA_CERTIFICATE] = { "ca-certificate", required_argument },
 248         {}
 249 };
 250
 251 int main(int argc, char **argv)
 252 {
 253         const char *progname = argv[0];
 254         struct uclient *cl;
 255         int ch;
 256         int longopt_idx = 0;
 257
 258         init_ustream_ssl();
 259
 260         while ((ch = getopt_long(argc, argv, "qO:", longopts, &longopt_idx)) != -1) {
 261                 switch(ch) {
 262                 case 0:
 263                         switch (longopt_idx) {
 264                         case L_NO_CHECK_CERTIFICATE:
 265                                 verify = false;
 266                                 break;
 267                         case L_CA_CERTIFICATE:
 268                                 if (ssl_ctx)
 269                                         ssl_ops->context_add_ca_crt_file(ssl_ctx, optarg);
 270                                 break;
 271                         default:
 272                                 return usage(progname);
 273                         }
 274                         break;
 275                 case 'O':
 276                         output_file = optarg;
 277                         break;
 278                 case 'q':
 279                         quiet = true;
 280                         break;
 281                 default:
 282                         return usage(progname);
 283                 }
 284         }
 285
 286         argv += optind;
 287         argc -= optind;
 288
 289         if (argc != 1)
 290                 return usage(progname);
 291
 292         if (!strncmp(argv[0], "https", 5) && !ssl_ctx)
 293                 return no_ssl(progname);
 294
 295         uloop_init();
 296
 297         cl = uclient_new(argv[0], NULL, &cb);
 298         if (!cl) {
 299                 fprintf(stderr, "Failed to allocate uclient context\n");
 300                 return 1;
 301         }
 302
 303         if (ssl_ctx)
 304                 uclient_http_set_ssl_ctx(cl, ssl_ops, ssl_ctx, verify);
 305
 306         init_request(cl);
 307         uloop_run();
 308         uloop_done();
 309
 310         uclient_free(cl);
 311
 312         if (output_fd >= 0 && output_fd != STDOUT_FILENO)
 313                 close(output_fd);
 314
 315         if (ssl_ctx)
 316                 ssl_ops->context_free(ssl_ctx);
 317
 318         return error_ret;
 319 }