diff options
Diffstat (limited to 'src/tools/tools_mc_util.c')
| -rw-r--r-- | src/tools/tools_mc_util.c | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/src/tools/tools_mc_util.c b/src/tools/tools_mc_util.c new file mode 100644 index 00000000..5348829e --- /dev/null +++ b/src/tools/tools_mc_util.c @@ -0,0 +1,187 @@ +/* + SSSD + + tools_mc_util - interface to the memcache for userspace tools + + Copyright (C) Red Hat 2013 + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +#include <talloc.h> +#include <fcntl.h> + +#include "util/util.h" +#include "tools/tools_util.h" +#include "util/mmap_cache.h" + +static errno_t sss_mc_set_recycled(int fd) +{ + uint32_t w = SSS_MC_HEADER_RECYCLED; + struct sss_mc_header h; + off_t offset; + off_t pos; + int ret; + + + offset = MC_PTR_DIFF(&h.status, &h); + + pos = lseek(fd, offset, SEEK_SET); + if (pos == -1) { + /* What do we do now ? */ + return errno; + } + + errno = 0; + ret = sss_atomic_write_s(fd, (uint8_t *)&w, sizeof(h.status)); + if (ret == -1) { + return errno; + } + + if (ret != sizeof(h.status)) { + /* Write error */ + return EIO; + } + + return EOK; +} + +errno_t sss_memcache_invalidate(const char *mc_filename) +{ + int mc_fd = -1; + errno_t ret; + errno_t pret; + useconds_t t = 50000; + int retries = 2; + + if (!mc_filename) { + return EINVAL; + } + + mc_fd = open(mc_filename, O_RDWR); + if (mc_fd == -1) { + ret = errno; + if (ret == ENOENT) { + DEBUG(SSSDBG_TRACE_FUNC,("Memory cache file %s " + "does not exist.\n", mc_filename)); + return EOK; + } else { + DEBUG(SSSDBG_CRIT_FAILURE, ("Unable to open file %s: %s\n", + mc_filename, strerror(ret))); + return ret; + } + } + + ret = sss_br_lock_file(mc_fd, 0, 1, retries, t); + if (ret == EACCES) { + DEBUG(SSSDBG_TRACE_FUNC, + ("File %s already locked by someone else.\n", mc_filename)); + goto done; + } else if (ret != EOK) { + DEBUG(SSSDBG_CRIT_FAILURE, ("Failed to lock file %s.\n", mc_filename)); + goto done; + } + /* Mark the mc file as recycled. */ + ret = sss_mc_set_recycled(mc_fd); + if (ret != EOK) { + DEBUG(SSSDBG_CRIT_FAILURE, ("Failed to mark memory cache file %s " + "as recycled.\n", mc_filename)); + goto done; + } + + ret = EOK; +done: + if (mc_fd != -1) { + /* Closing the file also releases the lock */ + close(mc_fd); + + /* Only unlink the file if invalidation was succesful */ + if (ret == EOK) { + pret = unlink(mc_filename); + if (pret == -1) { + DEBUG(SSSDBG_MINOR_FAILURE, + ("Failed to unlink file %s. " + "Will be unlinked later by sssd_nss.\n")); + } + } + } + return ret; +} + +static int clear_fastcache(bool *sssd_nss_is_off) +{ + int ret; + ret = sss_memcache_invalidate(SSS_NSS_MCACHE_DIR"/passwd"); + if (ret != EOK) { + if (ret == EACCES) { + *sssd_nss_is_off = false; + return EOK; + } else { + return ret; + } + } + + ret = sss_memcache_invalidate(SSS_NSS_MCACHE_DIR"/group"); + if (ret != EOK) { + if (ret == EACCES) { + *sssd_nss_is_off = false; + return EOK; + } else { + return ret; + } + } + + *sssd_nss_is_off = true; + return EOK; +} + +errno_t sss_memcache_clear_all(void) +{ + errno_t ret; + bool sssd_nss_is_off = false; + FILE *clear_mc_flag; + + ret = clear_fastcache(&sssd_nss_is_off); + if (ret != EOK) { + DEBUG(SSSDBG_CRIT_FAILURE, ("Failed to clear caches.\n")); + return EIO; + } + if (!sssd_nss_is_off) { + /* sssd_nss is running -> signal monitor to invalidate fastcache */ + clear_mc_flag = fopen(SSS_NSS_MCACHE_DIR"/"CLEAR_MC_FLAG, "w"); + if (clear_mc_flag == NULL) { + DEBUG(SSSDBG_CRIT_FAILURE, + ("Failed to create clear_mc_flag file. " + "Memory cache will not be cleared.\n")); + return EIO; + } + ret = fclose(clear_mc_flag); + if (ret != 0) { + ret = errno; + DEBUG(SSSDBG_CRIT_FAILURE, + ("Unable to close file descriptor: %s\n", + strerror(ret))); + return EIO; + } + DEBUG(SSSDBG_TRACE_FUNC, ("Sending SIGHUP to monitor.\n")); + ret = signal_sssd(SIGHUP); + if (ret != EOK) { + DEBUG(SSSDBG_CRIT_FAILURE, + ("Failed to send SIGHUP to monitor.\n")); + return EIO; + } + } + + return EOK; +} |