[FFmpeg-devel] [PATCH 1/7] avformat/ip: factorize some IP filtering and resolving functions to a new file
Marton Balint
cus at passwd.hu
Sun Sep 23 00:53:22 EEST 2018
These are based on the very similar UDP and RTP protocol functions.
Signed-off-by: Marton Balint <cus at passwd.hu>
---
libavformat/ip.c | 165 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
libavformat/ip.h | 74 +++++++++++++++++++++++++
2 files changed, 239 insertions(+)
create mode 100644 libavformat/ip.c
create mode 100644 libavformat/ip.h
diff --git a/libavformat/ip.c b/libavformat/ip.c
new file mode 100644
index 0000000000..d88055ebda
--- /dev/null
+++ b/libavformat/ip.c
@@ -0,0 +1,165 @@
+/*
+ * IP common code
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with FFmpeg; if not, write to the Free Software * Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "ip.h"
+
+static int compare_addr(const struct sockaddr_storage *a,
+ const struct sockaddr_storage *b)
+{
+ if (a->ss_family != b->ss_family)
+ return 1;
+ if (a->ss_family == AF_INET) {
+ return (((const struct sockaddr_in *)a)->sin_addr.s_addr !=
+ ((const struct sockaddr_in *)b)->sin_addr.s_addr);
+ }
+
+#if HAVE_STRUCT_SOCKADDR_IN6
+ if (a->ss_family == AF_INET6) {
+ const uint8_t *s6_addr_a = ((const struct sockaddr_in6 *)a)->sin6_addr.s6_addr;
+ const uint8_t *s6_addr_b = ((const struct sockaddr_in6 *)b)->sin6_addr.s6_addr;
+ return memcmp(s6_addr_a, s6_addr_b, 16);
+ }
+#endif
+ return 1;
+}
+
+int ff_ip_check_source_lists(struct sockaddr_storage *source_addr_ptr, IPSourceFilters *s)
+{
+ int i;
+ if (s->nb_exclude_addrs) {
+ for (i = 0; i < s->nb_exclude_addrs; i++) {
+ if (!compare_addr(source_addr_ptr, &s->exclude_addrs[i]))
+ return 1;
+ }
+ }
+ if (s->nb_include_addrs) {
+ for (i = 0; i < s->nb_include_addrs; i++) {
+ if (!compare_addr(source_addr_ptr, &s->include_addrs[i]))
+ return 0;
+ }
+ return 1;
+ }
+ return 0;
+}
+
+struct addrinfo *ff_ip_resolve_host(void *log_ctx,
+ const char *hostname, int port,
+ int type, int family, int flags)
+{
+ struct addrinfo hints = { 0 }, *res = 0;
+ int error;
+ char sport[16];
+ const char *node = 0, *service = "0";
+
+ if (port > 0) {
+ snprintf(sport, sizeof(sport), "%d", port);
+ service = sport;
+ }
+ if ((hostname) && (hostname[0] != '\0') && (hostname[0] != '?')) {
+ node = hostname;
+ }
+ hints.ai_socktype = type;
+ hints.ai_family = family;
+ hints.ai_flags = flags;
+ if ((error = getaddrinfo(node, service, &hints, &res))) {
+ res = NULL;
+ av_log(log_ctx, AV_LOG_ERROR, "getaddrinfo(%s, %s): %s\n",
+ node ? node : "unknown",
+ service,
+ gai_strerror(error));
+ }
+
+ return res;
+}
+
+
+static int ip_parse_addr_list(void *log_ctx, char *buf,
+ struct sockaddr_storage **address_list_ptr,
+ int *address_list_size_ptr)
+{
+ struct addrinfo *ai = NULL;
+ char tmp = '\0', *p = buf, *next;
+
+ /* Resolve all of the IPs */
+
+ while (p && p[0]) {
+ next = strchr(p, ',');
+
+ if (next) {
+ tmp = *next;
+ *next = '\0';
+ }
+
+ ai = ff_ip_resolve_host(log_ctx, p, 0, SOCK_DGRAM, AF_UNSPEC, 0);
+
+ if (next) {
+ *next = tmp;
+ p = next + 1;
+ } else {
+ p = NULL;
+ }
+
+ if (ai) {
+ struct sockaddr_storage source_addr = {0};
+ memcpy(&source_addr, ai->ai_addr, ai->ai_addrlen);
+ freeaddrinfo(ai);
+ av_dynarray2_add((void **)address_list_ptr, address_list_size_ptr, sizeof(source_addr), (uint8_t *)&source_addr);
+ if (!*address_list_ptr)
+ return AVERROR(ENOMEM);
+ } else {
+ return AVERROR(EINVAL);
+ }
+ }
+
+ return 0;
+}
+
+static int ip_parse_sources_and_blocks(void *log_ctx, char *buf, IPSourceFilters *filters, int parse_include_list)
+{
+ int ret;
+ if (parse_include_list)
+ ret = ip_parse_addr_list(log_ctx, buf, &filters->include_addrs, &filters->nb_include_addrs);
+ else
+ ret = ip_parse_addr_list(log_ctx, buf, &filters->exclude_addrs, &filters->nb_exclude_addrs);
+
+ if (ret >= 0 && filters->nb_include_addrs && filters->nb_exclude_addrs) {
+ av_log(log_ctx, AV_LOG_ERROR, "Simultaneously including and excluding sources is not supported.\n");
+ return AVERROR(EINVAL);
+ }
+ return ret;
+}
+
+int ff_ip_parse_sources(void *log_ctx, char *buf, IPSourceFilters *filters)
+{
+ return ip_parse_sources_and_blocks(log_ctx, buf, filters, 1);
+}
+
+int ff_ip_parse_blocks(void *log_ctx, char *buf, IPSourceFilters *filters)
+{
+ return ip_parse_sources_and_blocks(log_ctx, buf, filters, 0);
+}
+
+void ff_ip_reset_filters(IPSourceFilters *filters)
+{
+ av_freep(&filters->exclude_addrs);
+ av_freep(&filters->include_addrs);
+ filters->nb_include_addrs = 0;
+ filters->nb_exclude_addrs = 0;
+}
diff --git a/libavformat/ip.h b/libavformat/ip.h
new file mode 100644
index 0000000000..380143ff58
--- /dev/null
+++ b/libavformat/ip.h
@@ -0,0 +1,74 @@
+/*
+ * IP common code
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with FFmpeg; if not, write to the Free Software * Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVFORMAT_IP_H
+#define AVFORMAT_IP_H
+
+#include "network.h"
+
+/**
+ * Structure for storing IP (UDP) source filters or block lists.
+ */
+typedef struct IPSourceFilters {
+ int nb_include_addrs;
+ int nb_exclude_addrs;
+ struct sockaddr_storage *include_addrs;
+ struct sockaddr_storage *exclude_addrs;
+} IPSourceFilters;
+
+/**
+ * Checks the source address against a given IP source filter.
+ * @return 0 if packet should be processed based on the filter, 1 if the packet
+ * can be dropped.
+ */
+int ff_ip_check_source_lists(struct sockaddr_storage *source_addr_ptr, IPSourceFilters *s);
+
+/**
+ * Resolves hostname into an addrinfo structure.
+ * @return addrinfo structure which should be freed by the user, NULL in case
+ * of error.
+ */
+struct addrinfo *ff_ip_resolve_host(void *log_ctx,
+ const char *hostname, int port,
+ int type, int family, int flags);
+
+/**
+ * Parses the address[,address] source list in buf and adds it to the filters
+ * in the IPSourceFilters structure.
+ * @param buf is the source list, which is not changed, but must be writable
+ * @return 0 on success, < 0 AVERROR code on error.
+ */
+int ff_ip_parse_sources(void *log_ctx, char *buf, IPSourceFilters *filters);
+
+/**
+ * Parses the address[,address] source block list in buf and adds it to the
+ * filters in the IPSourceFilters structure.
+ * @param buf is the source list, which is not changed, but must be writable
+ * @return 0 on success, < 0 AVERROR code on error.
+ */
+int ff_ip_parse_blocks(void *log_ctx, char *buf, IPSourceFilters *filters);
+
+/**
+ * Resets the IP filter list and frees the internal fields of an
+ * IPSourceFilters structure.
+ */
+void ff_ip_reset_filters(IPSourceFilters *filters);
+
+#endif /* AVFORMAT_IP_H */
--
2.16.4
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