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
  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 bool verify = true;
  39 static const char *output_file;
  40 static int output_fd = -1;
  41 static int error_ret;
  42
  43 static int open_output_file(const char *path, bool create)
  44 {
  45         const char *str;
  46         char *filename;
  47         int len;
  48         int flags = O_WRONLY;
  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         len = strcspn(path, ";&");
  65         while (len > 0 && path[len - 1] == '/')
  66                 len--;
  67
  68         for (str = path + len - 1; str >= path; str--) {
  69                 if (*str == '/')
  70                         break;
  71         }
  72
  73         str++;
  74         len -= str - path;
  75
  76         if (len > 0) {
  77                 filename = alloca(len + 1);
  78                 strncpy(filename, str, len);
  79                 filename[len] = 0;
  80         } else {
  81                 filename = "index.html";
  82         }
  83
  84         return open(filename, flags, 0644);
  85 }
  86
  87 static void request_done(struct uclient *cl)
  88 {
  89         if (output_fd >= 0 && !output_file) {
  90                 close(output_fd);
  91                 output_fd = -1;
  92         }
  93         uclient_disconnect(cl);
  94         uloop_end();
  95 }
  96
  97 static void header_done_cb(struct uclient *cl)
  98 {
  99         static int retries;
 100
 101         if (retries < 10 && uclient_http_redirect(cl)) {
 102                 if (!quiet)
 103                         fprintf(stderr, "Redirected to %s on %s\n", cl->url->location, cl->url->host);
 104
 105                 retries++;
 106                 return;
 107         }
 108
 109         retries = 0;
 110         switch (cl->status_code) {
 111         case 204:
 112         case 200:
 113                 output_fd = open_output_file(cl->url->location, true);
 114                 if (output_fd < 0) {
 115                         if (!quiet)
 116                                 perror("Cannot open output file");
 117                         error_ret = 3;
 118                         request_done(cl);
 119                 }
 120                 break;
 121
 122         default:
 123                 if (!quiet)
 124                         fprintf(stderr, "HTTP error %d\n", cl->status_code);
 125                 request_done(cl);
 126                 error_ret = 8;
 127                 break;
 128         }
 129 }
 130
 131 static void read_data_cb(struct uclient *cl)
 132 {
 133         char buf[256];
 134         int len;
 135
 136         if (output_fd < 0)
 137                 return;
 138
 139         while (1) {
 140                 len = uclient_read(cl, buf, sizeof(buf));
 141                 if (!len)
 142                         return;
 143
 144                 write(output_fd, buf, len);
 145         }
 146 }
 147
 148 static void msg_connecting(struct uclient *cl)
 149 {
 150         char addr[INET6_ADDRSTRLEN];
 151         int port;
 152
 153         if (quiet)
 154                 return;
 155
 156         uclient_get_addr(addr, &port, &cl->remote_addr);
 157         fprintf(stderr, "Connecting to %s %s:%d\n", cl->url->host, addr, port);
 158 }
 159
 160 static void init_request(struct uclient *cl)
 161 {
 162         uclient_connect(cl);
 163         msg_connecting(cl);
 164         uclient_http_set_request_type(cl, "GET");
 165         uclient_request(cl);
 166 }
 167
 168 static void eof_cb(struct uclient *cl)
 169 {
 170         request_done(cl);
 171 }
 172
 173 static void handle_uclient_error(struct uclient *cl, int code)
 174 {
 175         const char *type = "Unknown error";
 176         bool ignore = false;
 177
 178         switch(code) {
 179         case UCLIENT_ERROR_CONNECT:
 180                 type = "Connection failed";
 181                 error_ret = 4;
 182                 break;
 183         case UCLIENT_ERROR_SSL_INVALID_CERT:
 184                 type = "Invalid SSL certificate";
 185                 ignore = !verify;
 186                 error_ret = 5;
 187                 break;
 188         case UCLIENT_ERROR_SSL_CN_MISMATCH:
 189                 type = "Server hostname does not match SSL certificate";
 190                 ignore = !verify;
 191                 error_ret = 5;
 192                 break;
 193         default:
 194                 error_ret = 1;
 195                 break;
 196         }
 197
 198         if (!quiet)
 199                 fprintf(stderr, "Connection error: %s%s\n", type, ignore ? " (ignored)" : "");
 200
 201         if (ignore)
 202                 error_ret = 0;
 203         else
 204                 request_done(cl);
 205 }
 206
 207 static const struct uclient_cb cb = {
 208         .header_done = header_done_cb,
 209         .data_read = read_data_cb,
 210         .data_eof = eof_cb,
 211         .error = handle_uclient_error,
 212 };
 213
 214 static int usage(const char *progname)
 215 {
 216         fprintf(stderr,
 217                 "Usage: %s [options] <URL>\n"
 218                 "Options:\n"
 219                 "       -q:                             Turn off status messages\n"
 220                 "       -O <file>:                      Redirect output to file (use \"-\" for stdout)\n"
 221                 "\n"
 222                 "HTTPS options:\n"
 223                 "       --ca-certificate=<cert>:        Load CA certificates from file <cert>\n"
 224                 "       --no-check-certificate:         don't validate the server's certificate\n"
 225                 "\n", progname);
 226         return 1;
 227 }
 228
 229
 230 static void init_ustream_ssl(void)
 231 {
 232         void *dlh;
 233
 234         dlh = dlopen("libustream-ssl." LIB_EXT, RTLD_LAZY | RTLD_LOCAL);
 235         if (!dlh)
 236                 return;
 237
 238         ssl_ops = dlsym(dlh, "ustream_ssl_ops");
 239         if (!ssl_ops)
 240                 return;
 241
 242         ssl_ctx = ssl_ops->context_new(false);
 243 }
 244
 245 static int no_ssl(const char *progname)
 246 {
 247         fprintf(stderr, "%s: SSL support not available, please install ustream-ssl\n", progname);
 248         return 1;
 249 }
 250
 251 enum {
 252         L_NO_CHECK_CERTIFICATE,
 253         L_CA_CERTIFICATE,
 254 };
 255
 256 static const struct option longopts[] = {
 257         [L_NO_CHECK_CERTIFICATE] = { "no-check-certificate", no_argument },
 258         [L_CA_CERTIFICATE] = { "ca-certificate", required_argument },
 259         {}
 260 };
 261
 262 int main(int argc, char **argv)
 263 {
 264         const char *progname = argv[0];
 265         struct uclient *cl;
 266         int ch;
 267         int longopt_idx = 0;
 268
 269         init_ustream_ssl();
 270
 271         while ((ch = getopt_long(argc, argv, "qO:", longopts, &longopt_idx)) != -1) {
 272                 switch(ch) {
 273                 case 0:
 274                         switch (longopt_idx) {
 275                         case L_NO_CHECK_CERTIFICATE:
 276                                 verify = false;
 277                                 break;
 278                         case L_CA_CERTIFICATE:
 279                                 if (ssl_ctx)
 280                                         ssl_ops->context_add_ca_crt_file(ssl_ctx, optarg);
 281                                 break;
 282                         default:
 283                                 return usage(progname);
 284                         }
 285                         break;
 286                 case 'O':
 287                         output_file = optarg;
 288                         break;
 289                 case 'q':
 290                         quiet = true;
 291                         break;
 292                 default:
 293                         return usage(progname);
 294                 }
 295         }
 296
 297         argv += optind;
 298         argc -= optind;
 299
 300         if (argc != 1)
 301                 return usage(progname);
 302
 303         if (!strncmp(argv[0], "https", 5) && !ssl_ctx)
 304                 return no_ssl(progname);
 305
 306         uloop_init();
 307
 308         cl = uclient_new(argv[0], NULL, &cb);
 309         if (!cl) {
 310                 fprintf(stderr, "Failed to allocate uclient context\n");
 311                 return 1;
 312         }
 313
 314         if (ssl_ctx)
 315                 uclient_http_set_ssl_ctx(cl, ssl_ops, ssl_ctx, verify);
 316
 317         init_request(cl);
 318         uloop_run();
 319         uloop_done();
 320
 321         uclient_free(cl);
 322
 323         if (output_fd >= 0 && output_fd != STDOUT_FILENO)
 324                 close(output_fd);
 325
 326         if (ssl_ctx)
 327                 ssl_ops->context_free(ssl_ctx);
 328
 329         return error_ret;
 330 }