diff options
Diffstat (limited to 'pppd_plugin/src/pptp_callmgr.c')
| -rw-r--r-- | pppd_plugin/src/pptp_callmgr.c | 403 |
1 files changed, 403 insertions, 0 deletions
diff --git a/pppd_plugin/src/pptp_callmgr.c b/pppd_plugin/src/pptp_callmgr.c new file mode 100644 index 0000000..988e717 --- /dev/null +++ b/pppd_plugin/src/pptp_callmgr.c @@ -0,0 +1,403 @@ +/* pptp_callmgr.c ... Call manager for PPTP connections. + * Handles TCP port 1723 protocol. + * C. Scott Ananian <cananian@alumni.princeton.edu> + * + * $Id: pptp_callmgr.c,v 1.20 2005/03/31 07:42:39 quozl Exp $ + */ +#include <signal.h> +#include <sys/time.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <arpa/inet.h> +#include <sys/un.h> +#include <unistd.h> +#include <stdlib.h> +#include <string.h> +#include <assert.h> +#include <setjmp.h> +#include <stdio.h> +#include <errno.h> +#include "pptp_callmgr.h" +#include "pptp_ctrl.h" +#include "pptp_msg.h" +#include "dirutil.h" +#include "vector.h" +#include "util.h" + +extern struct in_addr localbind; /* from pptp.c */ +extern int call_ID; + +int open_inetsock(struct in_addr inetaddr); +int open_unixsock(struct in_addr inetaddr); +void close_inetsock(int fd, struct in_addr inetaddr); +void close_unixsock(int fd, struct in_addr inetaddr); + +sigjmp_buf callmgr_env; + +void callmgr_sighandler(int sig) { + /* TODO: according to signal(2), siglongjmp() is unsafe used here */ + siglongjmp (callmgr_env, 1); +} + +void callmgr_do_nothing(int sig) { + /* do nothing signal handler */ +} + +struct local_callinfo { + int unix_sock; + pid_t pid[2]; +}; + +struct local_conninfo { + VECTOR * call_list; + fd_set * call_set; +}; + +/* Call callback */ +void call_callback(PPTP_CONN *conn, PPTP_CALL *call, enum call_state state) +{ + struct local_callinfo *lci; + struct local_conninfo *conninfo; + u_int16_t call_id[2]; + switch(state) { + case CALL_OPEN_DONE: + /* okey dokey. This means that the call_id and peer_call_id are + * now valid, so lets send them on to our friends who requested + * this call. */ + lci = pptp_call_closure_get(conn, call); assert(lci != NULL); + pptp_call_get_ids(conn, call, &call_id[0], &call_id[1]); + write(lci->unix_sock, &call_id, sizeof(call_id)); + /* Our duty to the fatherland is now complete. */ + break; + case CALL_OPEN_FAIL: + case CALL_CLOSE_RQST: + case CALL_CLOSE_DONE: + /* don't need to do anything here, except make sure tables + * are sync'ed */ + log("Closing connection (call state)"); + conninfo = pptp_conn_closure_get(conn); + lci = pptp_call_closure_get(conn, call); + assert(lci != NULL && conninfo != NULL); + if (vector_contains(conninfo->call_list, lci->unix_sock)) { + vector_remove(conninfo->call_list, lci->unix_sock); + close(lci->unix_sock); + FD_CLR(lci->unix_sock, conninfo->call_set); + if(lci->pid[0] > 1) kill(lci->pid[0], SIGTERM); + if(lci->pid[1] > 1) kill(lci->pid[1], SIGTERM); + } + break; + default: + log("Unhandled call callback state [%d].", (int) state); + break; + } +} + +/****************************************************************************** + * NOTE ABOUT 'VOLATILE': + * several variables here get a volatile qualifier to silence warnings + * from older (before 3.0) gccs. if the longjmp stuff is removed, + * the volatile qualifiers should be removed as well. + *****************************************************************************/ + +/*** Call Manager *************************************************************/ +int callmgr_main(int argc, char **argv, char **envp) +{ + struct in_addr inetaddr; + int inet_sock, unix_sock; + fd_set call_set; + PPTP_CONN * conn; + VECTOR * call_list; + int max_fd = 0; + volatile int first = 1; + int retval; + int i; + char * volatile phonenr=NULL; + int volatile window=10; + //int volatile call_id=0; + /* Step 0: Check arguments */ + if (argc < 2) + fatal("Usage: %s ip.add.ress.here [--phone <phone number>]", argv[0]); + //phonenr = argc == 3 ? argv[2] : NULL; + for(i=2; i<argc; i++) + { + //log("%s",argv[i]); + if (strcmp(argv[i],"--phone")==0 && i+1<argc) phonenr=argv[++i]; + else if (strcmp(argv[i],"--window")==0 && i+1<argc) window=atoi(argv[++i]); + else if (strcmp(argv[i],"--call_id")==0 && i+1<argc) call_ID=atoi(argv[++i]); + } + if (inet_aton(argv[1], &inetaddr) == 0) + fatal("Invalid IP address: %s", argv[1]); + log("IP: %s\n",inet_ntoa(inetaddr)); + /* Step 1: Open sockets. */ + if ((inet_sock = open_inetsock(inetaddr)) < 0) + fatal("Could not open control connection to %s", argv[1]); + log("control connection"); + if ((unix_sock = open_unixsock(inetaddr)) < 0) + fatal("Could not open unix socket for %s", argv[1]); + /* Step 1b: FORK and return status to calling process. */ + log("unix_sock"); + + switch (fork()) { + case 0: /* child. stick around. */ + break; + case -1: /* failure. Fatal. */ + fatal("Could not fork."); + default: /* Parent. Return status to caller. */ + exit(0); + } + /* re-open stderr as /dev/null to release it */ + file2fd("/dev/null", "wb", STDERR_FILENO); + /* Step 1c: Clean up unix socket on TERM */ + if (sigsetjmp(callmgr_env, 1) != 0) + goto cleanup; + signal(SIGINT, callmgr_sighandler); + signal(SIGTERM, callmgr_sighandler); + signal(SIGPIPE, callmgr_do_nothing); + signal(SIGUSR1, callmgr_do_nothing); /* signal state change + wake up accept */ + /* Step 2: Open control connection and register callback */ + if ((conn = pptp_conn_open(inet_sock, 1, NULL/* callback */)) == NULL) { + close(unix_sock); close(inet_sock); fatal("Could not open connection."); + } + FD_ZERO(&call_set); + call_list = vector_create(); + { + struct local_conninfo *conninfo = malloc(sizeof(*conninfo)); + if (conninfo == NULL) { + close(unix_sock); close(inet_sock); fatal("No memory."); + } + conninfo->call_list = call_list; + conninfo->call_set = &call_set; + pptp_conn_closure_put(conn, conninfo); + } + if (sigsetjmp(callmgr_env, 1) != 0) goto shutdown; + /* Step 3: Get FD_SETs */ + max_fd = unix_sock; + do { + int rc; + fd_set read_set = call_set, write_set; + FD_ZERO (&write_set); + if (pptp_conn_established(conn)) { + FD_SET (unix_sock, &read_set); + if (unix_sock > max_fd) max_fd = unix_sock; + } + pptp_fd_set(conn, &read_set, &write_set, &max_fd); + for (; max_fd > 0 ; max_fd--) { + if (FD_ISSET (max_fd, &read_set) || + FD_ISSET (max_fd, &write_set)) + break; + } + /* Step 4: Wait on INET or UNIX event */ + if ((rc = select(max_fd + 1, &read_set, &write_set, NULL, NULL)) <0) { + if (errno == EBADF) break; + /* a signal or somesuch. */ + continue; + } + /* Step 5a: Handle INET events */ + rc = pptp_dispatch(conn, &read_set, &write_set); + if (rc < 0) + break; + /* Step 5b: Handle new connection to UNIX socket */ + if (FD_ISSET(unix_sock, &read_set)) { + /* New call! */ + struct sockaddr_un from; + int len = sizeof(from); + PPTP_CALL * call; + struct local_callinfo *lci; + int s; + /* Accept the socket */ + FD_CLR (unix_sock, &read_set); + if ((s = accept(unix_sock, (struct sockaddr *) &from, &len)) < 0) { + warn("Socket not accepted: %s", strerror(errno)); + goto skip_accept; + } + /* Allocate memory for local call information structure. */ + if ((lci = malloc(sizeof(*lci))) == NULL) { + warn("Out of memory."); close(s); goto skip_accept; + } + lci->unix_sock = s; + /* Give the initiator time to write the PIDs while we open + * the call */ + call = pptp_call_open(conn, call_ID,call_callback, phonenr,window); + /* Read and store the associated pids */ + read(s, &lci->pid[0], sizeof(lci->pid[0])); + read(s, &lci->pid[1], sizeof(lci->pid[1])); + /* associate the local information with the call */ + pptp_call_closure_put(conn, call, (void *) lci); + /* The rest is done on callback. */ + /* Keep alive; wait for close */ + retval = vector_insert(call_list, s, call); assert(retval); + if (s > max_fd) max_fd = s; + FD_SET(s, &call_set); + first = 0; + } +skip_accept: /* Step 5c: Handle socket close */ + for (i = 0; i < max_fd + 1; i++) + if (FD_ISSET(i, &read_set)) { + /* close it */ + PPTP_CALL * call; + retval = vector_search(call_list, i, &call); + if (retval) { + struct local_callinfo *lci = + pptp_call_closure_get(conn, call); + log("Closing connection (unhandled)"); + if(lci->pid[0] > 1) kill(lci->pid[0], SIGTERM); + if(lci->pid[1] > 1) kill(lci->pid[1], SIGTERM); + free(lci); + /* soft shutdown. Callback will do hard shutdown later */ + pptp_call_close(conn, call); + vector_remove(call_list, i); + } + FD_CLR(i, &call_set); + close(i); + } + } while (vector_size(call_list) > 0 || first); +shutdown: + { + int rc; + fd_set read_set, write_set; + struct timeval tv; + signal(SIGINT, callmgr_do_nothing); + signal(SIGTERM, callmgr_do_nothing); + /* warn("Shutdown"); */ + /* kill all open calls */ + for (i = 0; i < vector_size(call_list); i++) { + PPTP_CALL *call = vector_get_Nth(call_list, i); + struct local_callinfo *lci = pptp_call_closure_get(conn, call); + log("Closing connection (shutdown)"); + pptp_call_close(conn, call); + if(lci->pid[0] > 1) kill(lci->pid[0], SIGTERM); + if(lci->pid[1] > 1) kill(lci->pid[1], SIGTERM); + } + /* attempt to dispatch these messages */ + FD_ZERO(&read_set); + FD_ZERO(&write_set); + pptp_fd_set(conn, &read_set, &write_set, &max_fd); + tv.tv_sec = 0; + tv.tv_usec = 0; + select(max_fd + 1, &read_set, &write_set, NULL, &tv); + rc = pptp_dispatch(conn, &read_set, &write_set); + if (rc > 0) { + /* wait for a respond, a timeout because there might not be one */ + FD_ZERO(&read_set); + FD_ZERO(&write_set); + pptp_fd_set(conn, &read_set, &write_set, &max_fd); + tv.tv_sec = 2; + tv.tv_usec = 0; + select(max_fd + 1, &read_set, &write_set, NULL, &tv); + rc = pptp_dispatch(conn, &read_set, &write_set); + if (rc > 0) { + if (i > 0) sleep(2); + /* no more open calls. Close the connection. */ + pptp_conn_close(conn, PPTP_STOP_LOCAL_SHUTDOWN); + /* wait for a respond, a timeout because there might not be one */ + FD_ZERO(&read_set); + FD_ZERO(&write_set); + pptp_fd_set(conn, &read_set, &write_set, &max_fd); + tv.tv_sec = 2; + tv.tv_usec = 0; + select(max_fd + 1, &read_set, &write_set, NULL, &tv); + pptp_dispatch(conn, &read_set, &write_set); + if (rc > 0) sleep(2); + } + } + /* with extreme prejudice */ + pptp_conn_destroy(conn); + vector_destroy(call_list); + } +cleanup: + signal(SIGINT, callmgr_do_nothing); + signal(SIGTERM, callmgr_do_nothing); + close_inetsock(inet_sock, inetaddr); + close_unixsock(unix_sock, inetaddr); + return 0; +} + +/*** open_inetsock ************************************************************/ +int open_inetsock(struct in_addr inetaddr) +{ + struct sockaddr_in dest, src; + int s; + dest.sin_family = AF_INET; + dest.sin_port = htons(PPTP_PORT); + dest.sin_addr = inetaddr; + if ((s = socket(AF_INET, SOCK_STREAM, 0)) < 0) { + warn("socket: %s", strerror(errno)); + return s; + } + if (localbind.s_addr != INADDR_NONE) { + bzero(&src, sizeof(src)); + src.sin_family = AF_INET; + src.sin_addr = localbind; + if (bind(s, (struct sockaddr *) &src, sizeof(src)) != 0) { + warn("bind: %s", strerror(errno)); + close(s); return -1; + } + } + if (connect(s, (struct sockaddr *) &dest, sizeof(dest)) < 0) { + warn("connect: %s", strerror(errno)); + close(s); return -1; + } + return s; +} + +/*** open_unixsock ************************************************************/ +int open_unixsock(struct in_addr inetaddr) +{ + struct sockaddr_un where; + struct stat st; + char *dir; + int s; + if ((s = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) { + warn("socket: %s", strerror(errno)); + return s; + } + callmgr_name_unixsock( &where, inetaddr, localbind); + if (stat(where.sun_path, &st) >= 0) + { + warn("Call manager for %s is already running.", inet_ntoa(inetaddr)); + close(s); return -1; + } + /* Make sure path is valid. */ + dir = dirnamex(where.sun_path); + if (!make_valid_path(dir, 0770)) + fatal("Could not make path to %s: %s", where.sun_path, strerror(errno)); + free(dir); + if (bind(s, (struct sockaddr *) &where, sizeof(where)) < 0) { + warn("bind: %s", strerror(errno)); + close(s); return -1; + } + chmod(where.sun_path, 0777); + listen(s, 127); + return s; +} + +/*** close_inetsock ***********************************************************/ +void close_inetsock(int fd, struct in_addr inetaddr) +{ + close(fd); +} + +/*** close_unixsock ***********************************************************/ +void close_unixsock(int fd, struct in_addr inetaddr) +{ + struct sockaddr_un where; + close(fd); + callmgr_name_unixsock(&where, inetaddr, localbind); + unlink(where.sun_path); +} + +/*** make a unix socket address ***********************************************/ +void callmgr_name_unixsock(struct sockaddr_un *where, + struct in_addr inetaddr, + struct in_addr localbind) +{ + char localaddr[16], remoteaddr[16]; + where->sun_family = AF_UNIX; + strncpy(localaddr, inet_ntoa(localbind), 16); + strncpy(remoteaddr, inet_ntoa(inetaddr), 16); + snprintf(where->sun_path, sizeof(where->sun_path), + PPTP_SOCKET_PREFIX "%s:%i", remoteaddr,call_ID); +} |