src/common/uri.cpp

   1 /*
   2  * Copyright (C) 2012 David Goulet <dgoulet@efficios.com>
   3  *
   4  * SPDX-License-Identifier: LGPL-2.1-only
   5  *
   6  */
   7
   8 #define _LGPL_SOURCE
   9 #include "uri.hpp"
  10
  11 #include <common/common.hpp>
  12 #include <common/compat/netdb.hpp>
  13 #include <common/defaults.hpp>
  14 #include <common/utils.hpp>
  15
  16 #include <arpa/inet.h>
  17 #include <stdlib.h>
  18 #include <string.h>
  19 #include <sys/socket.h>
  20
  21 #define LOOPBACK_ADDR_IPV4 "127.0.0.1"
  22 #define LOOPBACK_ADDR_IPV6 "::1"
  23
  24 enum uri_proto_code {
  25         P_NET,
  26         P_NET6,
  27         P_FILE,
  28         P_TCP,
  29         P_TCP6,
  30 };
  31
  32 namespace {
  33 struct uri_proto {
  34         const char *name;
  35         const char *leading_string;
  36         enum uri_proto_code code;
  37         enum lttng_proto_type type;
  38         enum lttng_dst_type dtype;
  39 };
  40
  41 /* Supported protocols */
  42 const struct uri_proto proto_uri[] = { { .name = "file",
  43                                          .leading_string = "file://",
  44                                          .code = P_FILE,
  45                                          .type = LTTNG_PROTO_TYPE_NONE,
  46                                          .dtype = LTTNG_DST_PATH },
  47                                        { .name = "net",
  48                                          .leading_string = "net://",
  49                                          .code = P_NET,
  50                                          .type = LTTNG_TCP,
  51                                          .dtype = LTTNG_DST_IPV4 },
  52                                        { .name = "net4",
  53                                          .leading_string = "net4://",
  54                                          .code = P_NET,
  55                                          .type = LTTNG_TCP,
  56                                          .dtype = LTTNG_DST_IPV4 },
  57                                        { .name = "net6",
  58                                          .leading_string = "net6://",
  59                                          .code = P_NET6,
  60                                          .type = LTTNG_TCP,
  61                                          .dtype = LTTNG_DST_IPV6 },
  62                                        { .name = "tcp",
  63                                          .leading_string = "tcp://",
  64                                          .code = P_TCP,
  65                                          .type = LTTNG_TCP,
  66                                          .dtype = LTTNG_DST_IPV4 },
  67                                        { .name = "tcp4",
  68                                          .leading_string = "tcp4://",
  69                                          .code = P_TCP,
  70                                          .type = LTTNG_TCP,
  71                                          .dtype = LTTNG_DST_IPV4 },
  72                                        { .name = "tcp6",
  73                                          .leading_string = "tcp6://",
  74                                          .code = P_TCP6,
  75                                          .type = LTTNG_TCP,
  76                                          .dtype = LTTNG_DST_IPV6 },
  77                                        /* Invalid proto marking the end of the array. */
  78                                        {} };
  79 } /* namespace */
  80
  81 /*
  82  * Return pointer to the character in s matching one of the characters in
  83  * accept. If nothing is found, return pointer to the end of string (eos).
  84  */
  85 static inline const char *strpbrk_or_eos(const char *s, const char *accept)
  86 {
  87         char *p = (char *) strpbrk(s, accept);
  88         if (p == nullptr) {
  89                 p = (char *) strchr(s, '\0');
  90         }
  91
  92         return p;
  93 }
  94
  95 /*
  96  * Validate if proto is a supported protocol from proto_uri array.
  97  */
  98 static const struct uri_proto *get_uri_proto(const char *uri_str)
  99 {
 100         const struct uri_proto *supported = nullptr;
 101
 102         /* Safety net */
 103         if (uri_str == nullptr) {
 104                 goto end;
 105         }
 106
 107         for (supported = &proto_uri[0]; supported->leading_string != nullptr; ++supported) {
 108                 if (strncasecmp(uri_str,
 109                                 supported->leading_string,
 110                                 strlen(supported->leading_string)) == 0) {
 111                         goto end;
 112                 }
 113         }
 114
 115         /* Proto not found */
 116         return nullptr;
 117
 118 end:
 119         return supported;
 120 }
 121
 122 /*
 123  * Set network address from string into dst. Supports both IP string and
 124  * hostname.
 125  */
 126 static int set_ip_address(const char *addr, int af, char *dst, size_t size)
 127 {
 128         int ret;
 129         unsigned char buf[sizeof(struct in6_addr)];
 130         struct hostent *record;
 131
 132         LTTNG_ASSERT(addr);
 133         LTTNG_ASSERT(dst);
 134
 135         memset(dst, 0, size);
 136
 137         /* Network protocol */
 138         ret = inet_pton(af, addr, buf);
 139         if (ret < 1) {
 140                 /* We consider the dst to be an hostname or an invalid IP char */
 141                 record = lttng_gethostbyname2(addr, af);
 142                 if (record) {
 143                         /* Translate IP to string */
 144                         if (!inet_ntop(af, record->h_addr_list[0], dst, size)) {
 145                                 PERROR("inet_ntop");
 146                                 goto error;
 147                         }
 148                 } else if (!strcmp(addr, "localhost") && (af == AF_INET || af == AF_INET6)) {
 149                         /*
 150                          * Some systems may not have "localhost" defined in
 151                          * accordance with IETF RFC 6761. According to this RFC,
 152                          * applications may recognize "localhost" names as
 153                          * special and resolve to the appropriate loopback
 154                          * address.
 155                          *
 156                          * We choose to use the system name resolution API first
 157                          * to honor its network configuration. If this fails, we
 158                          * resolve to the appropriate loopback address. This is
 159                          * done to accommodates systems which may want to start
 160                          * tracing before their network configured.
 161                          */
 162                         const char *loopback_addr = af == AF_INET ? LOOPBACK_ADDR_IPV4 :
 163                                                                     LOOPBACK_ADDR_IPV6;
 164                         const size_t loopback_addr_len = af == AF_INET ?
 165                                 sizeof(LOOPBACK_ADDR_IPV4) :
 166                                 sizeof(LOOPBACK_ADDR_IPV6);
 167
 168                         DBG2("Could not resolve localhost address, using fallback");
 169                         if (loopback_addr_len > size) {
 170                                 ERR("Could not resolve localhost address; destination string is too short");
 171                                 goto error;
 172                         }
 173                         strcpy(dst, loopback_addr);
 174                 } else {
 175                         /* At this point, the IP or the hostname is bad */
 176                         goto error;
 177                 }
 178         } else {
 179                 if (size > 0) {
 180                         strncpy(dst, addr, size);
 181                         dst[size - 1] = '\0';
 182                 }
 183         }
 184
 185         DBG2("IP address resolved to %s", dst);
 186         return 0;
 187
 188 error:
 189         ERR("URI parse bad hostname %s for af %d", addr, af);
 190         return -1;
 191 }
 192
 193 /*
 194  * Set default URI attribute which is basically the given stream type and the
 195  * default port if none is set in the URI.
 196  */
 197 static void set_default_uri_attr(struct lttng_uri *uri, enum lttng_stream_type stype)
 198 {
 199         uri->stype = stype;
 200         if (uri->dtype != LTTNG_DST_PATH && uri->port == 0) {
 201                 uri->port = (stype == LTTNG_STREAM_CONTROL) ? DEFAULT_NETWORK_CONTROL_PORT :
 202                                                               DEFAULT_NETWORK_DATA_PORT;
 203         }
 204 }
 205
 206 /*
 207  * Compare two URL destination.
 208  *
 209  * Return 0 is equal else is not equal.
 210  */
 211 static int compare_destination(struct lttng_uri *ctrl, struct lttng_uri *data)
 212 {
 213         int ret;
 214
 215         LTTNG_ASSERT(ctrl);
 216         LTTNG_ASSERT(data);
 217
 218         switch (ctrl->dtype) {
 219         case LTTNG_DST_IPV4:
 220                 ret = strncmp(ctrl->dst.ipv4, data->dst.ipv4, sizeof(ctrl->dst.ipv4));
 221                 break;
 222         case LTTNG_DST_IPV6:
 223                 ret = strncmp(ctrl->dst.ipv6, data->dst.ipv6, sizeof(ctrl->dst.ipv6));
 224                 break;
 225         default:
 226                 ret = -1;
 227                 break;
 228         }
 229
 230         return ret;
 231 }
 232
 233 /*
 234  * Build a string URL from a lttng_uri object.
 235  */
 236 int uri_to_str_url(struct lttng_uri *uri, char *dst, size_t size)
 237 {
 238         int ipver, ret;
 239         const char *addr;
 240         char proto[5], port[7];
 241
 242         LTTNG_ASSERT(uri);
 243         LTTNG_ASSERT(dst);
 244
 245         if (uri->dtype == LTTNG_DST_PATH) {
 246                 ipver = 0;
 247                 addr = uri->dst.path;
 248                 (void) snprintf(proto, sizeof(proto), "file");
 249                 (void) snprintf(port, sizeof(port), "%s", "");
 250         } else {
 251                 ipver = (uri->dtype == LTTNG_DST_IPV4) ? 4 : 6;
 252                 addr = (ipver == 4) ? uri->dst.ipv4 : uri->dst.ipv6;
 253                 (void) snprintf(proto, sizeof(proto), "tcp%d", ipver);
 254                 (void) snprintf(port, sizeof(port), ":%d", uri->port);
 255         }
 256
 257         ret = snprintf(dst,
 258                        size,
 259                        "%s://%s%s%s%s/%s",
 260                        proto,
 261                        (ipver == 6) ? "[" : "",
 262                        addr,
 263                        (ipver == 6) ? "]" : "",
 264                        port,
 265                        uri->subdir);
 266         if (ret < 0) {
 267                 PERROR("snprintf uri to url");
 268         }
 269
 270         return ret;
 271 }
 272
 273 /*
 274  * Compare two URIs.
 275  *
 276  * Return 0 if equal else 1.
 277  */
 278 int uri_compare(struct lttng_uri *uri1, struct lttng_uri *uri2)
 279 {
 280         return memcmp(uri1, uri2, sizeof(struct lttng_uri));
 281 }
 282
 283 /*
 284  * Free URI memory.
 285  */
 286 void uri_free(struct lttng_uri *uri)
 287 {
 288         free(uri);
 289 }
 290
 291 /*
 292  * Parses a string URI to a lttng_uri. This function can potentially return
 293  * more than one URI in uris so the size of the array is returned and uris is
 294  * allocated and populated. Caller must free(3) the array.
 295  *
 296  * This function can not detect the stream type of the URI so the caller has to
 297  * make sure the correct type (stype) is set on the return URI(s). The default
 298  * port must also be set by the caller if the returned URI has its port set to
 299  * zero.
 300  *
 301  * NOTE: A good part of the following code was inspired from the "wget" source
 302  * tree from the src/url.c file and url_parse() function. Also, the
 303  * strpbrk_or_eos() function found above is also inspired by the same code.
 304  * This code was originally licensed GPLv2 so we acknolwedge the Free Software
 305  * Foundation here for the work and to make sure we are compliant with it.
 306  */
 307 ssize_t uri_parse(const char *str_uri, struct lttng_uri **uris)
 308 {
 309         int ret, i = 0;
 310         /* Size of the uris array. Default is 1 */
 311         ssize_t size = 1;
 312         char subdir[PATH_MAX];
 313         unsigned int ctrl_port = 0;
 314         unsigned int data_port = 0;
 315         struct lttng_uri *tmp_uris;
 316         char *addr_f = nullptr;
 317         const struct uri_proto *proto;
 318         const char *purl, *addr_e, *addr_b, *subdir_b = nullptr;
 319         const char *seps = ":/\0";
 320
 321         /*
 322          * The first part is the protocol portion of a maximum of 5 bytes for now.
 323          * The second part is the hostname or IP address. The 255 bytes size is the
 324          * limit found in the RFC 1035 for the total length of a domain name
 325          * (https://www.ietf.org/rfc/rfc1035.txt). Finally, for the net://
 326          * protocol, two ports CAN be specified.
 327          */
 328
 329         DBG3("URI string: %s", str_uri);
 330
 331         proto = get_uri_proto(str_uri);
 332         if (proto == nullptr) {
 333                 ERR("URI parse unknown protocol %s", str_uri);
 334                 goto error;
 335         }
 336
 337         purl = str_uri;
 338
 339         if (proto->code == P_NET || proto->code == P_NET6) {
 340                 /* Special case for net:// which requires two URI objects */
 341                 size = 2;
 342         }
 343
 344         /* Allocate URI array */
 345         tmp_uris = calloc<lttng_uri>(size);
 346         if (tmp_uris == nullptr) {
 347                 PERROR("zmalloc uri");
 348                 goto error;
 349         }
 350
 351         memset(subdir, 0, sizeof(subdir));
 352         purl += strlen(proto->leading_string);
 353
 354         /* Copy known value to the first URI. */
 355         tmp_uris[0].dtype = proto->dtype;
 356         tmp_uris[0].proto = proto->type;
 357
 358         if (proto->code == P_FILE) {
 359                 if (*purl != '/') {
 360                         ERR("Missing destination full path.");
 361                         goto free_error;
 362                 }
 363
 364                 strncpy(tmp_uris[0].dst.path, purl, sizeof(tmp_uris[0].dst.path));
 365                 tmp_uris[0].dst.path[sizeof(tmp_uris[0].dst.path) - 1] = '\0';
 366                 DBG3("URI file destination: %s", purl);
 367                 goto end;
 368         }
 369
 370         /* Assume we are at the beginning of an address or host of some sort. */
 371         addr_b = purl;
 372
 373         /*
 374          * Handle IPv6 address inside square brackets as mention by RFC 2732. IPv6
 375          * address that does not start AND end with brackets will be rejected even
 376          * if valid.
 377          *
 378          * proto://[<addr>]...
 379          *         ^
 380          */
 381         if (*purl == '[') {
 382                 /* Address begins after '[' */
 383                 addr_b = purl + 1;
 384                 addr_e = strchr(addr_b, ']');
 385                 if (addr_e == nullptr || addr_b == addr_e) {
 386                         ERR("Broken IPv6 address %s", addr_b);
 387                         goto free_error;
 388                 }
 389
 390                 /* Moving parsed URL pointer after the final bracket ']' */
 391                 purl = addr_e + 1;
 392
 393                 /*
 394                  * The closing bracket must be followed by a seperator or NULL char.
 395                  */
 396                 if (strchr(seps, *purl) == nullptr) {
 397                         ERR("Unknown symbol after IPv6 address: %s", purl);
 398                         goto free_error;
 399                 }
 400         } else {
 401                 purl = strpbrk_or_eos(purl, seps);
 402                 addr_e = purl;
 403         }
 404
 405         /* Check if we at least have a char for the addr or hostname. */
 406         if (addr_b == addr_e) {
 407                 ERR("No address or hostname detected.");
 408                 goto free_error;
 409         }
 410
 411         addr_f = utils_strdupdelim(addr_b, addr_e);
 412         if (addr_f == nullptr) {
 413                 goto free_error;
 414         }
 415
 416         /*
 417          * Detect PORT after address. The net/net6 protocol allows up to two port
 418          * so we can define the control and data port.
 419          */
 420         while (*purl == ':') {
 421                 const char *port_b, *port_e;
 422                 char *port_f;
 423
 424                 /* Update pass counter */
 425                 i++;
 426
 427                 /*
 428                  * Maximum of two ports is possible if P_NET/NET6. Bigger than that,
 429                  * two much stuff.
 430                  */
 431                 if ((i == 2 && (proto->code != P_NET && proto->code != P_NET6)) || i > 2) {
 432                         break;
 433                 }
 434
 435                 /*
 436                  * Move parsed URL to port value.
 437                  * proto://addr_host:PORT1:PORT2/foo/bar
 438                  *                   ^
 439                  */
 440                 ++purl;
 441                 port_b = purl;
 442                 purl = strpbrk_or_eos(purl, seps);
 443                 port_e = purl;
 444
 445                 if (port_b != port_e) {
 446                         int port;
 447
 448                         port_f = utils_strdupdelim(port_b, port_e);
 449                         if (port_f == nullptr) {
 450                                 goto free_error;
 451                         }
 452
 453                         port = atoi(port_f);
 454                         if (port > 0xffff || port <= 0x0) {
 455                                 ERR("Invalid port number %d", port);
 456                                 free(port_f);
 457                                 goto free_error;
 458                         }
 459                         free(port_f);
 460
 461                         if (i == 1) {
 462                                 ctrl_port = port;
 463                         } else {
 464                                 data_port = port;
 465                         }
 466                 }
 467         };
 468
 469         /* Check for a valid subdir or trailing garbage */
 470         if (*purl == '/') {
 471                 /*
 472                  * Move to subdir value.
 473                  * proto://addr_host:PORT1:PORT2/foo/bar
 474                  *                               ^
 475                  */
 476                 ++purl;
 477                 subdir_b = purl;
 478         } else if (*purl != '\0') {
 479                 ERR("Trailing characters not recognized: %s", purl);
 480                 goto free_error;
 481         }
 482
 483         /* We have enough valid information to create URI(s) object */
 484
 485         /* Copy generic information */
 486         tmp_uris[0].port = ctrl_port;
 487
 488         /* Copy subdirectory if one. */
 489         if (subdir_b) {
 490                 strncpy(tmp_uris[0].subdir, subdir_b, sizeof(tmp_uris[0].subdir));
 491                 tmp_uris[0].subdir[sizeof(tmp_uris[0].subdir) - 1] = '\0';
 492         }
 493
 494         switch (proto->code) {
 495         case P_NET:
 496                 ret = set_ip_address(
 497                         addr_f, AF_INET, tmp_uris[0].dst.ipv4, sizeof(tmp_uris[0].dst.ipv4));
 498                 if (ret < 0) {
 499                         goto free_error;
 500                 }
 501
 502                 memcpy(tmp_uris[1].dst.ipv4, tmp_uris[0].dst.ipv4, sizeof(tmp_uris[1].dst.ipv4));
 503
 504                 tmp_uris[1].dtype = proto->dtype;
 505                 tmp_uris[1].proto = proto->type;
 506                 tmp_uris[1].port = data_port;
 507                 break;
 508         case P_NET6:
 509                 ret = set_ip_address(
 510                         addr_f, AF_INET6, tmp_uris[0].dst.ipv6, sizeof(tmp_uris[0].dst.ipv6));
 511                 if (ret < 0) {
 512                         goto free_error;
 513                 }
 514
 515                 memcpy(tmp_uris[1].dst.ipv6, tmp_uris[0].dst.ipv6, sizeof(tmp_uris[1].dst.ipv6));
 516
 517                 tmp_uris[1].dtype = proto->dtype;
 518                 tmp_uris[1].proto = proto->type;
 519                 tmp_uris[1].port = data_port;
 520                 break;
 521         case P_TCP:
 522                 ret = set_ip_address(
 523                         addr_f, AF_INET, tmp_uris[0].dst.ipv4, sizeof(tmp_uris[0].dst.ipv4));
 524                 if (ret < 0) {
 525                         goto free_error;
 526                 }
 527                 break;
 528         case P_TCP6:
 529                 ret = set_ip_address(
 530                         addr_f, AF_INET6, tmp_uris[0].dst.ipv6, sizeof(tmp_uris[0].dst.ipv6));
 531                 if (ret < 0) {
 532                         goto free_error;
 533                 }
 534                 break;
 535         default:
 536                 goto free_error;
 537         }
 538
 539 end:
 540         DBG3("URI dtype: %d, proto: %d, host: %s, subdir: %s, ctrl: %d, data: %d",
 541              proto->dtype,
 542              proto->type,
 543              (addr_f == NULL) ? "" : addr_f,
 544              (subdir_b == NULL) ? "" : subdir_b,
 545              ctrl_port,
 546              data_port);
 547
 548         free(addr_f);
 549
 550         *uris = tmp_uris;
 551         LTTNG_ASSERT(size == 1 || size == 2);
 552         return size;
 553
 554 free_error:
 555         free(addr_f);
 556         free(tmp_uris);
 557 error:
 558         return -1;
 559 }
 560
 561 /*
 562  * Parse a string URL and creates URI(s) returning the size of the populated
 563  * array.
 564  */
 565 ssize_t uri_parse_str_urls(const char *ctrl_url, const char *data_url, struct lttng_uri **uris)
 566 {
 567         unsigned int equal = 1, idx = 0;
 568         /* Add the "file://" size to the URL maximum size */
 569         char url[PATH_MAX + 7];
 570         ssize_t ctrl_uri_count = 0, data_uri_count = 0, uri_count;
 571         struct lttng_uri *ctrl_uris = nullptr, *data_uris = nullptr;
 572         struct lttng_uri *tmp_uris = nullptr;
 573
 574         /* No URL(s) is allowed. This means that the consumer will be disabled. */
 575         if (ctrl_url == nullptr && data_url == nullptr) {
 576                 return 0;
 577         }
 578
 579         /* Check if URLs are equal and if so, only use the control URL */
 580         if ((ctrl_url && *ctrl_url != '\0') && (data_url && *data_url != '\0')) {
 581                 equal = !strcmp(ctrl_url, data_url);
 582         }
 583
 584         /*
 585          * Since we allow the str_url to be a full local filesystem path, we are
 586          * going to create a valid file:// URL if it's the case.
 587          *
 588          * Check if first character is a '/' or else reject the URL.
 589          */
 590         if (ctrl_url && ctrl_url[0] == '/') {
 591                 int ret;
 592
 593                 ret = snprintf(url, sizeof(url), "file://%s", ctrl_url);
 594                 if (ret < 0) {
 595                         PERROR("snprintf file url");
 596                         goto parse_error;
 597                 } else if (ret >= sizeof(url)) {
 598                         PERROR("snprintf file url is too long");
 599                         goto parse_error;
 600                 }
 601                 ctrl_url = url;
 602         }
 603
 604         /* Parse the control URL if there is one */
 605         if (ctrl_url && *ctrl_url != '\0') {
 606                 ctrl_uri_count = uri_parse(ctrl_url, &ctrl_uris);
 607                 if (ctrl_uri_count < 1) {
 608                         ERR("Unable to parse the URL %s", ctrl_url);
 609                         goto parse_error;
 610                 }
 611
 612                 /* 1 and 2 are the only expected values on success. */
 613                 LTTNG_ASSERT(ctrl_uri_count == 1 || ctrl_uri_count == 2);
 614
 615                 /* At this point, we know there is at least one URI in the array */
 616                 set_default_uri_attr(&ctrl_uris[0], LTTNG_STREAM_CONTROL);
 617
 618                 if (ctrl_uris[0].dtype == LTTNG_DST_PATH && (data_url && *data_url != '\0')) {
 619                         ERR("Cannot have a data URL when destination is file://");
 620                         goto error;
 621                 }
 622
 623                 /* URL are not equal but the control URL uses a net:// protocol */
 624                 if (ctrl_uri_count == 2) {
 625                         if (!equal) {
 626                                 ERR("Control URL uses the net:// protocol and the data URL is "
 627                                     "different. Not allowed.");
 628                                 goto error;
 629                         } else {
 630                                 set_default_uri_attr(&ctrl_uris[1], LTTNG_STREAM_DATA);
 631                                 /*
 632                                  * The data_url and ctrl_url are equal and the ctrl_url
 633                                  * contains a net:// protocol so we just skip the data part.
 634                                  */
 635                                 data_url = nullptr;
 636                         }
 637                 }
 638         }
 639
 640         if (data_url && *data_url != '\0') {
 641                 int ret;
 642
 643                 /* We have to parse the data URL in this case */
 644                 data_uri_count = uri_parse(data_url, &data_uris);
 645                 if (data_uri_count < 1) {
 646                         ERR("Unable to parse the URL %s", data_url);
 647                         goto error;
 648                 } else if (data_uri_count == 2) {
 649                         ERR("Data URL can not be set with the net[4|6]:// protocol");
 650                         goto error;
 651                 } else {
 652                         /* 1 and 2 are the only expected values on success. */
 653                         LTTNG_ASSERT(data_uri_count == 1);
 654                 }
 655
 656                 set_default_uri_attr(&data_uris[0], LTTNG_STREAM_DATA);
 657
 658                 if (ctrl_uris) {
 659                         ret = compare_destination(&ctrl_uris[0], &data_uris[0]);
 660                         if (ret != 0) {
 661                                 ERR("Control and data destination mismatch");
 662                                 goto error;
 663                         }
 664                 }
 665         }
 666
 667         /* Compute total size. */
 668         uri_count = ctrl_uri_count + data_uri_count;
 669         if (uri_count <= 0) {
 670                 goto error;
 671         }
 672
 673         tmp_uris = calloc<lttng_uri>(uri_count);
 674         if (tmp_uris == nullptr) {
 675                 PERROR("zmalloc uris");
 676                 goto error;
 677         }
 678
 679         if (ctrl_uris) {
 680                 /* It's possible the control URIs array contains more than one URI */
 681                 memcpy(tmp_uris, ctrl_uris, sizeof(struct lttng_uri) * ctrl_uri_count);
 682                 ++idx;
 683                 free(ctrl_uris);
 684         }
 685
 686         if (data_uris) {
 687                 memcpy(&tmp_uris[idx], data_uris, sizeof(struct lttng_uri));
 688                 free(data_uris);
 689         }
 690
 691         *uris = tmp_uris;
 692
 693         return uri_count;
 694
 695 error:
 696         free(ctrl_uris);
 697         free(data_uris);
 698         free(tmp_uris);
 699 parse_error:
 700         return -1;
 701 }