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 #define _GNU_SOURCE
  20 #include <unistd.h>
  21 #include <stdio.h>
  22 #include <dlfcn.h>
  23 #include <getopt.h>
  24 #include <fcntl.h>
  25 #include <glob.h>
  26
  27 #include <libubox/blobmsg.h>
  28
  29 #include "uclient.h"
  30 #include "uclient-utils.h"
  31
  32 #ifdef __APPLE__
  33 #define LIB_EXT "dylib"
  34 #else
  35 #define LIB_EXT "so"
  36 #endif
  37
  38 static struct ustream_ssl_ctx *ssl_ctx;
  39 static const struct ustream_ssl_ops *ssl_ops;
  40 static int quiet = false;
  41 static bool verify = true;
  42 static bool default_certs = false;
  43 static const char *output_file;
  44 static int output_fd = -1;
  45 static int error_ret;
  46 static int out_bytes;
  47 static char *username;
  48 static char *password;
  49 static char *auth_str;
  50
  51 static int open_output_file(const char *path, bool create)
  52 {
  53         char *filename;
  54         int flags = O_WRONLY;
  55         int ret;
  56
  57         if (create)
  58                 flags |= O_CREAT | O_EXCL;
  59
  60         if (output_file) {
  61                 if (!strcmp(output_file, "-"))
  62                         return STDOUT_FILENO;
  63
  64                 if (!quiet)
  65                         fprintf(stderr, "Writing to stdout\n");
  66
  67                 unlink(output_file);
  68                 return open(output_file, flags, 0644);
  69         }
  70
  71         filename = uclient_get_url_filename(path, "index.html");
  72         if (!quiet)
  73                 fprintf(stderr, "Writing to '%s'\n", filename);
  74         ret = open(filename, flags, 0644);
  75         free(filename);
  76
  77         return ret;
  78 }
  79
  80 static void request_done(struct uclient *cl)
  81 {
  82         if (output_fd >= 0 && !output_file) {
  83                 close(output_fd);
  84                 output_fd = -1;
  85         }
  86         uclient_disconnect(cl);
  87         uloop_end();
  88 }
  89
  90 static void header_done_cb(struct uclient *cl)
  91 {
  92         static int retries;
  93
  94         if (retries < 10 && uclient_http_redirect(cl)) {
  95                 if (!quiet)
  96                         fprintf(stderr, "Redirected to %s on %s\n", cl->url->location, cl->url->host);
  97
  98                 retries++;
  99                 return;
 100         }
 101
 102         retries = 0;
 103         switch (cl->status_code) {
 104         case 204:
 105         case 200:
 106                 output_fd = open_output_file(cl->url->location, true);
 107                 if (output_fd < 0) {
 108                         if (!quiet)
 109                                 perror("Cannot open output file");
 110                         error_ret = 3;
 111                         request_done(cl);
 112                 }
 113                 break;
 114
 115         default:
 116                 if (!quiet)
 117                         fprintf(stderr, "HTTP error %d\n", cl->status_code);
 118                 request_done(cl);
 119                 error_ret = 8;
 120                 break;
 121         }
 122 }
 123
 124 static void read_data_cb(struct uclient *cl)
 125 {
 126         char buf[256];
 127         int len;
 128
 129         if (output_fd < 0)
 130                 return;
 131
 132         while (1) {
 133                 len = uclient_read(cl, buf, sizeof(buf));
 134                 if (!len)
 135                         return;
 136
 137                 out_bytes += len;
 138                 write(output_fd, buf, len);
 139         }
 140 }
 141
 142 static void msg_connecting(struct uclient *cl)
 143 {
 144         char addr[INET6_ADDRSTRLEN];
 145         int port;
 146
 147         if (quiet)
 148                 return;
 149
 150         uclient_get_addr(addr, &port, &cl->remote_addr);
 151         fprintf(stderr, "Connecting to %s:%d\n", addr, port);
 152 }
 153
 154 static int init_request(struct uclient *cl)
 155 {
 156         int rc;
 157
 158         out_bytes = 0;
 159
 160         rc = uclient_connect(cl);
 161         if (rc)
 162                 return rc;
 163
 164         msg_connecting(cl);
 165
 166         rc = uclient_http_set_request_type(cl, "GET");
 167         if (rc)
 168                 return rc;
 169
 170         rc = uclient_request(cl);
 171         if (rc)
 172                 return rc;
 173
 174         return 0;
 175 }
 176
 177 static void eof_cb(struct uclient *cl)
 178 {
 179         if (!cl->data_eof) {
 180                 if (!quiet)
 181                         fprintf(stderr, "Connection reset prematurely\n");
 182                 error_ret = 4;
 183         } else if (!quiet) {
 184                 fprintf(stderr, "Download completed (%d bytes)\n", out_bytes);
 185         }
 186         request_done(cl);
 187 }
 188
 189 static void handle_uclient_error(struct uclient *cl, int code)
 190 {
 191         const char *type = "Unknown error";
 192         bool ignore = false;
 193
 194         switch(code) {
 195         case UCLIENT_ERROR_CONNECT:
 196                 type = "Connection failed";
 197                 error_ret = 4;
 198                 break;
 199         case UCLIENT_ERROR_TIMEDOUT:
 200                 type = "Connection timed out";
 201                 error_ret = 4;
 202                 break;
 203         case UCLIENT_ERROR_SSL_INVALID_CERT:
 204                 type = "Invalid SSL certificate";
 205                 ignore = !verify;
 206                 error_ret = 5;
 207                 break;
 208         case UCLIENT_ERROR_SSL_CN_MISMATCH:
 209                 type = "Server hostname does not match SSL certificate";
 210                 ignore = !verify;
 211                 error_ret = 5;
 212                 break;
 213         default:
 214                 error_ret = 1;
 215                 break;
 216         }
 217
 218         if (!quiet)
 219                 fprintf(stderr, "Connection error: %s%s\n", type, ignore ? " (ignored)" : "");
 220
 221         if (ignore)
 222                 error_ret = 0;
 223         else
 224                 request_done(cl);
 225 }
 226
 227 static const struct uclient_cb cb = {
 228         .header_done = header_done_cb,
 229         .data_read = read_data_cb,
 230         .data_eof = eof_cb,
 231         .error = handle_uclient_error,
 232 };
 233
 234 static int usage(const char *progname)
 235 {
 236         fprintf(stderr,
 237                 "Usage: %s [options] <URL>\n"
 238                 "Options:\n"
 239                 "       -q:                             Turn off status messages\n"
 240                 "       -O <file>:                      Redirect output to file (use \"-\" for stdout)\n"
 241                 "       --user=<user>                   HTTP authentication username\n"
 242                 "       --password=<password>           HTTP authentication password\n"
 243                 "\n"
 244                 "HTTPS options:\n"
 245                 "       --ca-certificate=<cert>:        Load CA certificates from file <cert>\n"
 246                 "       --no-check-certificate:         don't validate the server's certificate\n"
 247                 "\n", progname);
 248         return 1;
 249 }
 250
 251 static void init_ca_cert(void)
 252 {
 253         glob_t gl;
 254         int i;
 255
 256         glob("/etc/ssl/certs/*.crt", 0, NULL, &gl);
 257         for (i = 0; i < gl.gl_pathc; i++)
 258                 ssl_ops->context_add_ca_crt_file(ssl_ctx, gl.gl_pathv[i]);
 259 }
 260
 261 static void init_ustream_ssl(void)
 262 {
 263         void *dlh;
 264
 265         dlh = dlopen("libustream-ssl." LIB_EXT, RTLD_LAZY | RTLD_LOCAL);
 266         if (!dlh)
 267                 return;
 268
 269         ssl_ops = dlsym(dlh, "ustream_ssl_ops");
 270         if (!ssl_ops)
 271                 return;
 272
 273         ssl_ctx = ssl_ops->context_new(false);
 274 }
 275
 276 static int no_ssl(const char *progname)
 277 {
 278         fprintf(stderr, "%s: SSL support not available, please install ustream-ssl\n", progname);
 279         return 1;
 280 }
 281
 282 enum {
 283         L_NO_CHECK_CERTIFICATE,
 284         L_CA_CERTIFICATE,
 285         L_USER,
 286         L_PASSWORD,
 287 };
 288
 289 static const struct option longopts[] = {
 290         [L_NO_CHECK_CERTIFICATE] = { "no-check-certificate", no_argument },
 291         [L_CA_CERTIFICATE] = { "ca-certificate", required_argument },
 292         [L_USER] = { "user", required_argument },
 293         [L_PASSWORD] = { "password", required_argument },
 294         {}
 295 };
 296
 297 int main(int argc, char **argv)
 298 {
 299         const char *progname = argv[0];
 300         struct uclient *cl;
 301         int ch;
 302         int longopt_idx = 0;
 303         bool has_cert = false;
 304         int rc;
 305
 306         init_ustream_ssl();
 307
 308         while ((ch = getopt_long(argc, argv, "qO:", longopts, &longopt_idx)) != -1) {
 309                 switch(ch) {
 310                 case 0:
 311                         switch (longopt_idx) {
 312                         case L_NO_CHECK_CERTIFICATE:
 313                                 verify = false;
 314                                 break;
 315                         case L_CA_CERTIFICATE:
 316                                 has_cert = true;
 317                                 if (ssl_ctx)
 318                                         ssl_ops->context_add_ca_crt_file(ssl_ctx, optarg);
 319                                 break;
 320                         case L_USER:
 321                                 if (!strlen(optarg))
 322                                         break;
 323                                 username = strdup(optarg);
 324                                 memset(optarg, '*', strlen(optarg));
 325                                 break;
 326                         case L_PASSWORD:
 327                                 if (!strlen(optarg))
 328                                         break;
 329                                 password = strdup(optarg);
 330                                 memset(optarg, '*', strlen(optarg));
 331                                 break;
 332                         default:
 333                                 return usage(progname);
 334                         }
 335                         break;
 336                 case 'O':
 337                         output_file = optarg;
 338                         break;
 339                 case 'q':
 340                         quiet = true;
 341                         break;
 342                 default:
 343                         return usage(progname);
 344                 }
 345         }
 346
 347         argv += optind;
 348         argc -= optind;
 349
 350         if (verify && !has_cert)
 351                 default_certs = true;
 352
 353         if (argc != 1)
 354                 return usage(progname);
 355
 356         if (!strncmp(argv[0], "https", 5) && !ssl_ctx)
 357                 return no_ssl(progname);
 358
 359         uloop_init();
 360
 361         if (username) {
 362                 if (password)
 363                         asprintf(&auth_str, "%s:%s", username, password);
 364                 else
 365                         auth_str = username;
 366         }
 367
 368         if (!quiet)
 369                 fprintf(stderr, "Downloading '%s'\n", argv[0]);
 370
 371         cl = uclient_new(argv[0], auth_str, &cb);
 372         if (!cl) {
 373                 fprintf(stderr, "Failed to allocate uclient context\n");
 374                 return 1;
 375         }
 376
 377         if (ssl_ctx) {
 378                 init_ca_cert();
 379                 uclient_http_set_ssl_ctx(cl, ssl_ops, ssl_ctx, verify);
 380         }
 381
 382         rc = init_request(cl);
 383         if (!rc) {
 384                 /* no error received, we can enter main loop */
 385                 uloop_run();
 386         } else {
 387                 fprintf(stderr, "Failed to establish connection\n");
 388                 error_ret = 4;
 389         }
 390
 391         uloop_done();
 392
 393         uclient_free(cl);
 394
 395         if (output_fd >= 0 && output_fd != STDOUT_FILENO)
 396                 close(output_fd);
 397
 398         if (ssl_ctx)
 399                 ssl_ops->context_free(ssl_ctx);
 400
 401         return error_ret;
 402 }