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Diffstat (limited to 'source4/nsswitch/wb_common.c')
| -rw-r--r-- | source4/nsswitch/wb_common.c | 433 |
1 files changed, 433 insertions, 0 deletions
diff --git a/source4/nsswitch/wb_common.c b/source4/nsswitch/wb_common.c new file mode 100644 index 0000000000..89c751a4ef --- /dev/null +++ b/source4/nsswitch/wb_common.c @@ -0,0 +1,433 @@ +/* + Unix SMB/CIFS implementation. + + winbind client common code + + Copyright (C) Tim Potter 2000 + Copyright (C) Andrew Tridgell 2000 + Copyright (C) Andrew Bartlett 2002 + + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public + License as published by the Free Software Foundation; either + version 2 of the License, or (at your option) any later version. + + This library 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with this library; if not, write to the + Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. +*/ + +#include "winbind_client.h" + +/* Global variables. These are effectively the client state information */ + +int winbindd_fd = -1; /* fd for winbindd socket */ + +/* Free a response structure */ + +void free_response(struct winbindd_response *response) +{ + /* Free any allocated extra_data */ + + if (response) + SAFE_FREE(response->extra_data); +} + +/* Initialise a request structure */ + +void init_request(struct winbindd_request *request, int request_type) +{ + request->length = sizeof(struct winbindd_request); + + request->cmd = (enum winbindd_cmd)request_type; + request->pid = getpid(); + +} + +/* Initialise a response structure */ + +void init_response(struct winbindd_response *response) +{ + /* Initialise return value */ + + response->result = WINBINDD_ERROR; +} + +/* Close established socket */ + +void close_sock(void) +{ + if (winbindd_fd != -1) { + close(winbindd_fd); + winbindd_fd = -1; + } +} + +/* Make sure socket handle isn't stdin, stdout or stderr */ +#define RECURSION_LIMIT 3 + +static int make_nonstd_fd_internals(int fd, int limit /* Recursion limiter */) +{ + int new_fd; + if (fd >= 0 && fd <= 2) { +#ifdef F_DUPFD + if ((new_fd = fcntl(fd, F_DUPFD, 3)) == -1) { + return -1; + } + /* Parinoia */ + if (new_fd < 3) { + close(new_fd); + return -1; + } + close(fd); + return new_fd; +#else + if (limit <= 0) + return -1; + + new_fd = dup(fd); + if (new_fd == -1) + return -1; + + /* use the program stack to hold our list of FDs to close */ + new_fd = make_nonstd_fd_internals(new_fd, limit - 1); + close(fd); + return new_fd; +#endif + } + return fd; +} + +static int make_safe_fd(int fd) +{ + int result, flags; + int new_fd = make_nonstd_fd_internals(fd, RECURSION_LIMIT); + if (new_fd == -1) { + close(fd); + return -1; + } + /* Socket should be closed on exec() */ + +#ifdef FD_CLOEXEC + result = flags = fcntl(new_fd, F_GETFD, 0); + if (flags >= 0) { + flags |= FD_CLOEXEC; + result = fcntl( new_fd, F_SETFD, flags ); + } + if (result < 0) { + close(new_fd); + return -1; + } +#endif + return new_fd; +} + +/* Connect to winbindd socket */ + +int winbind_open_pipe_sock(void) +{ +#ifdef HAVE_UNIXSOCKET + struct sockaddr_un sunaddr; + static pid_t our_pid; + struct stat st; + pstring path; + int fd; + + if (our_pid != getpid()) { + close_sock(); + our_pid = getpid(); + } + + if (winbindd_fd != -1) { + return winbindd_fd; + } + + /* Check permissions on unix socket directory */ + + if (lstat(WINBINDD_SOCKET_DIR, &st) == -1) { + return -1; + } + + if (!S_ISDIR(st.st_mode) || + (st.st_uid != 0 && st.st_uid != geteuid())) { + return -1; + } + + /* Connect to socket */ + + strncpy(path, WINBINDD_SOCKET_DIR, sizeof(path) - 1); + path[sizeof(path) - 1] = '\0'; + + strncat(path, "/", sizeof(path) - 1); + path[sizeof(path) - 1] = '\0'; + + strncat(path, WINBINDD_SOCKET_NAME, sizeof(path) - 1); + path[sizeof(path) - 1] = '\0'; + + ZERO_STRUCT(sunaddr); + sunaddr.sun_family = AF_UNIX; + strncpy(sunaddr.sun_path, path, sizeof(sunaddr.sun_path) - 1); + + /* If socket file doesn't exist, don't bother trying to connect + with retry. This is an attempt to make the system usable when + the winbindd daemon is not running. */ + + if (lstat(path, &st) == -1) { + return -1; + } + + /* Check permissions on unix socket file */ + + if (!S_ISSOCK(st.st_mode) || + (st.st_uid != 0 && st.st_uid != geteuid())) { + return -1; + } + + /* Connect to socket */ + + if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) { + return -1; + } + + if ((winbindd_fd = make_safe_fd( fd)) == -1) { + return winbindd_fd; + } + + if (connect(winbindd_fd, (struct sockaddr *)&sunaddr, + sizeof(sunaddr)) == -1) { + close_sock(); + return -1; + } + + return winbindd_fd; +#else + return -1; +#endif /* HAVE_UNIXSOCKET */ +} + +/* Write data to winbindd socket */ + +int write_sock(void *buffer, int count) +{ + int result, nwritten; + + /* Open connection to winbind daemon */ + + restart: + + if (winbind_open_pipe_sock() == -1) { + return -1; + } + + /* Write data to socket */ + + nwritten = 0; + + while(nwritten < count) { + struct timeval tv; + fd_set r_fds; + + /* Catch pipe close on other end by checking if a read() + call would not block by calling select(). */ + + FD_ZERO(&r_fds); + FD_SET(winbindd_fd, &r_fds); + ZERO_STRUCT(tv); + + if (select(winbindd_fd + 1, &r_fds, NULL, NULL, &tv) == -1) { + close_sock(); + return -1; /* Select error */ + } + + /* Write should be OK if fd not available for reading */ + + if (!FD_ISSET(winbindd_fd, &r_fds)) { + + /* Do the write */ + + result = write(winbindd_fd, + (char *)buffer + nwritten, + count - nwritten); + + if ((result == -1) || (result == 0)) { + + /* Write failed */ + + close_sock(); + return -1; + } + + nwritten += result; + + } else { + + /* Pipe has closed on remote end */ + + close_sock(); + goto restart; + } + } + + return nwritten; +} + +/* Read data from winbindd socket */ + +static int read_sock(void *buffer, int count) +{ + int result = 0, nread = 0; + + /* Read data from socket */ + + while(nread < count) { + + result = read(winbindd_fd, (char *)buffer + nread, + count - nread); + + if ((result == -1) || (result == 0)) { + + /* Read failed. I think the only useful thing we + can do here is just return -1 and fail since the + transaction has failed half way through. */ + + close_sock(); + return -1; + } + + nread += result; + } + + return result; +} + +/* Read reply */ + +int read_reply(struct winbindd_response *response) +{ + int result1, result2 = 0; + + if (!response) { + return -1; + } + + /* Read fixed length response */ + + if ((result1 = read_sock(response, sizeof(struct winbindd_response))) + == -1) { + + return -1; + } + + /* We actually send the pointer value of the extra_data field from + the server. This has no meaning in the client's address space + so we clear it out. */ + + response->extra_data = NULL; + + /* Read variable length response */ + + if (response->length > sizeof(struct winbindd_response)) { + int extra_data_len = response->length - + sizeof(struct winbindd_response); + + /* Mallocate memory for extra data */ + + if (!(response->extra_data = malloc(extra_data_len))) { + return -1; + } + + if ((result2 = read_sock(response->extra_data, extra_data_len)) + == -1) { + free_response(response); + return -1; + } + } + + /* Return total amount of data read */ + + return result1 + result2; +} + +/* + * send simple types of requests + */ + +NSS_STATUS winbindd_send_request(int req_type, struct winbindd_request *request) +{ + struct winbindd_request lrequest; + + /* Check for our tricky environment variable */ + + if (getenv(WINBINDD_DONT_ENV)) { + return NSS_STATUS_NOTFOUND; + } + + if (!request) { + ZERO_STRUCT(lrequest); + request = &lrequest; + } + + /* Fill in request and send down pipe */ + + init_request(request, req_type); + + if (write_sock(request, sizeof(*request)) == -1) { + return NSS_STATUS_UNAVAIL; + } + + return NSS_STATUS_SUCCESS; +} + +/* + * Get results from winbindd request + */ + +NSS_STATUS winbindd_get_response(struct winbindd_response *response) +{ + struct winbindd_response lresponse; + + if (!response) { + ZERO_STRUCT(lresponse); + response = &lresponse; + } + + init_response(response); + + /* Wait for reply */ + if (read_reply(response) == -1) { + return NSS_STATUS_UNAVAIL; + } + + /* Throw away extra data if client didn't request it */ + if (response == &lresponse) { + free_response(response); + } + + /* Copy reply data from socket */ + if (response->result != WINBINDD_OK) { + return NSS_STATUS_NOTFOUND; + } + + return NSS_STATUS_SUCCESS; +} + +/* Handle simple types of requests */ + +NSS_STATUS winbindd_request(int req_type, + struct winbindd_request *request, + struct winbindd_response *response) +{ + NSS_STATUS status; + + status = winbindd_send_request(req_type, request); + if (status != NSS_STATUS_SUCCESS) + return(status); + return winbindd_get_response(response); +} |