diff options
Diffstat (limited to 'src/osmo-bts-virtual/osmo_mcast_sock.c')
| -rw-r--r-- | src/osmo-bts-virtual/osmo_mcast_sock.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/src/osmo-bts-virtual/osmo_mcast_sock.c b/src/osmo-bts-virtual/osmo_mcast_sock.c new file mode 100644 index 00000000..c1777347 --- /dev/null +++ b/src/osmo-bts-virtual/osmo_mcast_sock.c @@ -0,0 +1,192 @@ +#include <netinet/in.h> +#include <arpa/inet.h> +#include <netdb.h> +#include <osmocom/core/socket.h> +#include <osmocom/core/select.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <talloc.h> +#include <unistd.h> + +#include "osmo_mcast_sock.h" + +struct mcast_server_sock *mcast_server_sock_setup(void *ctx, + char* tx_mcast_group, + int tx_mcast_port, + int loopback) +{ + struct mcast_server_sock *serv_sock = talloc_zero(ctx, + struct mcast_server_sock); + + serv_sock->osmo_fd = talloc_zero(ctx, struct osmo_fd); + serv_sock->sock_conf = talloc_zero(ctx, struct sockaddr_in); + + // setup mcast server socket + serv_sock->osmo_fd->fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); + if (serv_sock->osmo_fd->fd == -1) { + perror("Failed to create Multicast Server Socket"); + return NULL; + } + + serv_sock->sock_conf->sin_family = AF_INET; + serv_sock->sock_conf->sin_addr.s_addr = inet_addr(tx_mcast_group); + serv_sock->sock_conf->sin_port = htons(tx_mcast_port); + + // determines whether sent mcast packets should be looped back to the local sockets. + // loopback must be enabled if the mcast client is on the same machine + if (setsockopt(serv_sock->osmo_fd->fd, IPPROTO_IP, + IP_MULTICAST_LOOP, &loopback, sizeof(loopback)) < 0) { + perror("Failed to disable loopback.\n"); + return NULL; + } + + return serv_sock; +} + +struct mcast_client_sock *mcast_client_sock_setup( + void *ctx, char* mcast_group, int mcast_port, + int (*fd_rx_cb)(struct osmo_fd *ofd, unsigned int what), + void *osmo_fd_data) +{ + struct mcast_client_sock *client_sock = talloc_zero(ctx, + struct mcast_client_sock); + struct sockaddr_in *rx_sock_conf = talloc_zero(NULL, + struct sockaddr_in); + int rc, reuseaddr = 1, loopback = 1; + + client_sock->osmo_fd = talloc_zero(ctx, struct osmo_fd); + client_sock->mcast_group = talloc_zero(ctx, struct ip_mreq); + + // Create mcast client socket + client_sock->osmo_fd->fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); + if (client_sock->osmo_fd->fd == -1) { + perror("Could not create mcast client socket"); + return NULL; + } + + // Enable SO_REUSEADDR to allow multiple instances of this application to receive copies of the multicast datagrams. + rc = setsockopt(client_sock->osmo_fd->fd, + SOL_SOCKET, + SO_REUSEADDR, &reuseaddr, sizeof(reuseaddr)); + if (rc < 0) { + perror("Failed to configure REUSEADDR option"); + return NULL; + } + + // Bind to the proper port number with the IP address specified as INADDR_ANY. + rx_sock_conf->sin_family = AF_INET; + rx_sock_conf->sin_addr.s_addr = htonl(INADDR_ANY); + rx_sock_conf->sin_port = htons(mcast_port); + rc = bind(client_sock->osmo_fd->fd, (struct sockaddr *)rx_sock_conf, + sizeof(*rx_sock_conf)); + talloc_free(rx_sock_conf); + if (rc < 0) { + perror("Could not bind mcast client socket"); + return NULL; + } + + // Enable loopback of msgs to the host. + // Loopback must be enabled for the client, so multiple processes are able to recevie a mcast package. + rc = setsockopt(client_sock->osmo_fd->fd, + IPPROTO_IP, + IP_MULTICAST_LOOP, &loopback, sizeof(loopback)); + if (rc < 0) { + perror("Failed to enable IP_MULTICAST_LOOP"); + return NULL; + } + + // Configure and join the multicast group + client_sock->mcast_group->imr_multiaddr.s_addr = inet_addr(mcast_group); + client_sock->mcast_group->imr_interface.s_addr = htonl(INADDR_ANY); + rc = setsockopt(client_sock->osmo_fd->fd, + IPPROTO_IP, + IP_ADD_MEMBERSHIP, client_sock->mcast_group, + sizeof(*client_sock->mcast_group)); + if (rc < 0) { + perror("Failed to join to mcast goup"); + return NULL; + } + + // configure and register the osmocom filedescriptor + client_sock->osmo_fd->cb = fd_rx_cb; + client_sock->osmo_fd->when = BSC_FD_READ; + client_sock->osmo_fd->data = osmo_fd_data; + + osmo_fd_register(client_sock->osmo_fd); + + return client_sock; +} + +struct mcast_bidir_sock *mcast_bidir_sock_setup( + void *ctx, char* tx_mcast_group, int tx_mcast_port, + char* rx_mcast_group, int rx_mcast_port, int loopback, + int (*fd_rx_cb)(struct osmo_fd *ofd, unsigned int what), + void *osmo_fd_data) +{ + struct mcast_bidir_sock *bidir_sock = talloc(ctx, + struct mcast_bidir_sock); + bidir_sock->rx_sock = mcast_client_sock_setup(ctx, rx_mcast_group, + rx_mcast_port, fd_rx_cb, osmo_fd_data); + bidir_sock->tx_sock = mcast_server_sock_setup(ctx, tx_mcast_group, + tx_mcast_port, loopback); + if (!bidir_sock->rx_sock || !bidir_sock->tx_sock) { + return NULL; + } + return bidir_sock; + +} + +int mcast_client_sock_rx(struct mcast_client_sock *client_sock, void* buf, + int buf_len) +{ + return recv(client_sock->osmo_fd->fd, buf, buf_len, 0); +} + +int mcast_server_sock_tx(struct mcast_server_sock *serv_sock, void* data, + int data_len) +{ + return sendto(serv_sock->osmo_fd->fd, data, data_len, 0, + (struct sockaddr *)serv_sock->sock_conf, + sizeof(*serv_sock->sock_conf)); +} + +int mcast_bidir_sock_tx(struct mcast_bidir_sock *bidir_sock, void* data, + int data_len) +{ + return mcast_server_sock_tx(bidir_sock->tx_sock, data, data_len); +} +int mcast_bidir_sock_rx(struct mcast_bidir_sock *bidir_sock, void* buf, + int buf_len) +{ + return mcast_client_sock_rx(bidir_sock->rx_sock, buf, buf_len); +} + +void mcast_client_sock_close(struct mcast_client_sock *client_sock) +{ + setsockopt(client_sock->osmo_fd->fd, + IPPROTO_IP, + IP_DROP_MEMBERSHIP, client_sock->mcast_group, + sizeof(*client_sock->mcast_group)); + osmo_fd_unregister(client_sock->osmo_fd); + client_sock->osmo_fd->fd = -1; + client_sock->osmo_fd->when = 0; + close(client_sock->osmo_fd->fd); + talloc_free(client_sock->mcast_group); + talloc_free(client_sock->osmo_fd); + talloc_free(client_sock); + +} +void mcast_server_sock_close(struct mcast_server_sock *serv_sock) +{ + close(serv_sock->osmo_fd->fd); + talloc_free(serv_sock->sock_conf); + talloc_free(serv_sock); +} + +void mcast_bidir_sock_close(struct mcast_bidir_sock *bidir_sock) +{ + mcast_client_sock_close(bidir_sock->rx_sock); + mcast_server_sock_close(bidir_sock->tx_sock); + talloc_free(bidir_sock); +} |