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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2022-01-14 15:03:48 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2022-01-14 15:03:48 +0000 |
commit | be956cd27353a4bb585b1a648e8469cf7adb5edf (patch) | |
tree | a473793c3fd59ace461f23a8d75d9ca29a82b4ff /examples/receiver.c | |
parent | Initial commit. (diff) | |
download | dnswire-be956cd27353a4bb585b1a648e8469cf7adb5edf.tar.xz dnswire-be956cd27353a4bb585b1a648e8469cf7adb5edf.zip |
Adding upstream version 0.2.0.upstream/0.2.0
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'examples/receiver.c')
-rw-r--r-- | examples/receiver.c | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/examples/receiver.c b/examples/receiver.c new file mode 100644 index 0000000..316e1ec --- /dev/null +++ b/examples/receiver.c @@ -0,0 +1,169 @@ +#include <dnswire/reader.h> + +#include <stdio.h> +#include <errno.h> +#include <arpa/inet.h> +#include <stdlib.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <sys/un.h> + +#include "print_dnstap.c" + +int main(int argc, const char* argv[]) +{ + if (argc < 2) { + fprintf(stderr, "usage: receiver [ <IP> <port> | <unix socket path> ]\n"); + return 1; + } + + /* + * We first initialize the reader and check that it can allocate the + * buffers it needs. + */ + + struct dnswire_reader reader; + + if (dnswire_reader_init(&reader) != dnswire_ok) { + fprintf(stderr, "Unable to initialize dnswire reader\n"); + return 1; + } + + /* + * Allow bidirectional communication over the TCP or UNIX socket. + */ + if (dnswire_reader_allow_bidirectional(&reader, true) != dnswire_ok) { + fprintf(stderr, "Unable to set dnswire reader to bidirectional mode\n"); + return 1; + } + + int sockfd; + + if (argc == 2) { + /* + * We setup a unix socket at the given path on command line. + */ + + struct sockaddr_un path; + + memset(&path, 0, sizeof(struct sockaddr_un)); + path.sun_family = AF_UNIX; + strncpy(path.sun_path, argv[1], sizeof(path.sun_path) - 1); + + sockfd = socket(AF_UNIX, SOCK_STREAM, 0); + if (sockfd == -1) { + fprintf(stderr, "socket() failed: %s\n", strerror(errno)); + return 1; + } + printf("socket\n"); + + if (bind(sockfd, (struct sockaddr*)&path, sizeof(struct sockaddr_un))) { + fprintf(stderr, "bind() failed: %s\n", strerror(errno)); + close(sockfd); + return 1; + } + printf("bind\n"); + } else { + /* + * We setup and listen on the IP and port given on command line. + */ + + struct sockaddr_storage addr_store; + struct sockaddr_in* addr = (struct sockaddr_in*)&addr_store; + socklen_t addrlen; + + if (strchr(argv[1], ':')) { + addr->sin_family = AF_INET6; + addrlen = sizeof(struct sockaddr_in6); + } else { + addr->sin_family = AF_INET; + addrlen = sizeof(struct sockaddr_in); + } + + if (inet_pton(addr->sin_family, argv[1], &addr->sin_addr) != 1) { + fprintf(stderr, "inet_pton(%s) failed: %s\n", argv[1], strerror(errno)); + return 1; + } + + addr->sin_port = ntohs(atoi(argv[2])); + + sockfd = socket(addr->sin_family, SOCK_STREAM, IPPROTO_TCP); + if (sockfd == -1) { + fprintf(stderr, "socket() failed: %s\n", strerror(errno)); + return 1; + } + printf("socket\n"); + + if (bind(sockfd, (struct sockaddr*)addr, addrlen)) { + fprintf(stderr, "bind() failed: %s\n", strerror(errno)); + close(sockfd); + return 1; + } + printf("bind\n"); + } + + if (listen(sockfd, 1)) { + fprintf(stderr, "listen() failed: %s\n", strerror(errno)); + close(sockfd); + return 1; + } + printf("listen\n"); + + int clifd = accept(sockfd, 0, 0); + if (clifd < 0) { + fprintf(stderr, "accept() failed: %s\n", strerror(errno)); + close(sockfd); + return 1; + } + printf("accept\n"); + + /* + * We have accepted connection from the sender! + * + * We now loop until we have a DNSTAP message, the stream was stopped + * or we got an error. + */ + + int done = 0; + + printf("receiving...\n"); + while (!done) { + switch (dnswire_reader_read(&reader, clifd)) { + case dnswire_have_dnstap: + /* + * We received a DNSTAP message, let's print it. + */ + print_dnstap(dnswire_reader_dnstap(reader)); + break; + case dnswire_again: + case dnswire_need_more: + /* + * This indicates that we need to call the reader again as it + * will only do one pass in a non-blocking fasion. + */ + break; + case dnswire_endofdata: + /* + * The stream was stopped from the sender side, we're done! + */ + printf("stopped\n"); + done = 1; + break; + default: + fprintf(stderr, "dnswire_reader_read() error\n"); + done = 1; + } + } + + dnswire_reader_destroy(reader); + + /* + * Time to exit, let's shutdown and close the sockets. + */ + + shutdown(clifd, SHUT_RDWR); + close(clifd); + close(sockfd); + + return 0; +} |