From 505e75ba28b42bb3de7a6d55de825091b70cc2b2 Mon Sep 17 00:00:00 2001 From: Stephen Gallagher Date: Sun, 22 Apr 2012 13:52:51 -0400 Subject: LDAP: Add helper routines for ID-mapping --- Makefile.am | 8 +- src/providers/ldap/sdap_idmap.c | 282 ++++++++++++++++++++++++++++++++++++++++ src/providers/ldap/sdap_idmap.h | 52 ++++++++ 3 files changed, 340 insertions(+), 2 deletions(-) create mode 100644 src/providers/ldap/sdap_idmap.c create mode 100644 src/providers/ldap/sdap_idmap.h diff --git a/Makefile.am b/Makefile.am index d31515e9b..348ad2787 100644 --- a/Makefile.am +++ b/Makefile.am @@ -1096,6 +1096,8 @@ libsss_ldap_common_la_SOURCES = \ src/providers/ldap/sdap_child_helpers.c \ src/providers/ldap/sdap_fd_events.c \ src/providers/ldap/sdap_id_op.c \ + src/providers/ldap/sdap_idmap.c \ + src/providers/ldap/sdap_idmap.h \ src/providers/ldap/sdap.c if BUILD_SUDO @@ -1140,7 +1142,8 @@ libsss_ldap_la_LIBADD = \ $(DHASH_LIBS) \ $(KRB5_LIBS) \ libsss_util.la \ - libsss_ldap_common.la + libsss_ldap_common.la \ + libsss_idmap.la libsss_ldap_la_LDFLAGS = \ -avoid-version \ -module @@ -1231,7 +1234,8 @@ libsss_ipa_la_LIBADD = \ libsss_util.la \ libsss_ldap_common.la \ libsss_krb5_common.la \ - libipa_hbac.la + libipa_hbac.la \ + libsss_idmap.la libsss_ipa_la_LDFLAGS = \ -avoid-version \ -module diff --git a/src/providers/ldap/sdap_idmap.c b/src/providers/ldap/sdap_idmap.c new file mode 100644 index 000000000..ea65195ac --- /dev/null +++ b/src/providers/ldap/sdap_idmap.c @@ -0,0 +1,282 @@ +/* + SSSD + + Authors: + Stephen Gallagher + + Copyright (C) 2012 Red Hat + + 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 . +*/ + +#include "util/util.h" +#include "util/dlinklist.h" +#include "util/murmurhash3.h" +#include "providers/ldap/sdap_idmap.h" + +static void * +sdap_idmap_talloc(size_t size, void *pvt) +{ + return talloc_size(pvt, size); +} + +static void +sdap_idmap_talloc_free(void *ptr, void *pvt) +{ + talloc_free(ptr); +} + +errno_t +sdap_idmap_init(TALLOC_CTX *mem_ctx, + struct sdap_id_ctx *id_ctx, + struct sdap_idmap_ctx **_idmap_ctx) +{ + errno_t ret; + TALLOC_CTX *tmp_ctx; + enum idmap_error_code err; + size_t i; + struct ldb_result *res; + const char *dom_name; + const char *sid_str; + id_t slice_num; + struct sdap_idmap_ctx *idmap_ctx = NULL; + struct sysdb_ctx *sysdb = id_ctx->be->sysdb; + + tmp_ctx = talloc_new(NULL); + if (!tmp_ctx) return ENOMEM; + + idmap_ctx = talloc_zero(tmp_ctx, struct sdap_idmap_ctx); + if (!idmap_ctx) { + ret = ENOMEM; + goto done; + } + idmap_ctx->id_ctx = id_ctx; + + /* Initialize the map */ + err = sss_idmap_init(sdap_idmap_talloc, idmap_ctx, + sdap_idmap_talloc_free, + &idmap_ctx->map); + if (err != IDMAP_SUCCESS) { + DEBUG(SSSDBG_CRIT_FAILURE, + ("Could not initialize the ID map: [%s]\n", + idmap_error_string(err))); + if (err == IDMAP_OUT_OF_MEMORY) { + ret = ENOMEM; + } else { + ret = EINVAL; + } + goto done; + } + + /* Read in any existing mappings from the cache */ + ret = sysdb_idmap_get_mappings(tmp_ctx, sysdb, &res); + if (ret != EOK && ret != ENOENT) { + DEBUG(SSSDBG_FATAL_FAILURE, + ("Could not read ID mappings from the cache: [%s]\n", + strerror(ret))); + goto done; + } + + if (ret == EOK && res->count > 0) { + DEBUG(SSSDBG_CONF_SETTINGS, + ("Initializing [%d] domains for ID-mapping\n", res->count)); + + for (i = 0; i < res->count; i++) { + dom_name = ldb_msg_find_attr_as_string(res->msgs[i], + SYSDB_NAME, + NULL); + if (!dom_name) { + /* This should never happen */ + ret = EINVAL; + goto done; + } + + sid_str = ldb_msg_find_attr_as_string(res->msgs[i], + SYSDB_IDMAP_SID_ATTR, + NULL); + if (!sid_str) { + /* This should never happen */ + ret = EINVAL; + goto done; + } + + slice_num = ldb_msg_find_attr_as_int(res->msgs[i], + SYSDB_IDMAP_SLICE_ATTR, + -1); + if (slice_num == -1) { + /* This should never happen */ + ret = EINVAL; + goto done; + } + + ret = sdap_idmap_add_domain(idmap_ctx, dom_name, + sid_str, slice_num); + if (ret != EOK) { + DEBUG(SSSDBG_CRIT_FAILURE, + ("Could not add domain [%s][%s][%u] to ID map: [%s]\n", + dom_name, sid_str, slice_num, strerror(ret))); + goto done; + } + } + } + + *_idmap_ctx = talloc_steal(mem_ctx, idmap_ctx); + ret = EOK; + +done: + talloc_free(tmp_ctx); + return ret; +} + +errno_t +sdap_idmap_add_domain(struct sdap_idmap_ctx *idmap_ctx, + const char *dom_name, + const char *dom_sid, + id_t slice) +{ + errno_t ret; + struct sdap_idmap_slice *new_slice; + id_t idmap_lower; + id_t idmap_upper; + id_t rangesize; + id_t max_slices; + id_t orig_slice; + uint32_t hash_val; + struct sdap_idmap_slice *s; + struct sss_idmap_range range; + enum idmap_error_code err; + + idmap_lower = dp_opt_get_int(idmap_ctx->id_ctx->opts->basic, + SDAP_IDMAP_LOWER); + idmap_upper = dp_opt_get_int(idmap_ctx->id_ctx->opts->basic, + SDAP_IDMAP_UPPER); + rangesize = dp_opt_get_int(idmap_ctx->id_ctx->opts->basic, + SDAP_IDMAP_RANGESIZE); + + /* Validate that the values make sense */ + if (rangesize <= 0 + || idmap_upper <= idmap_lower + || (idmap_upper-idmap_lower) < rangesize) + { + DEBUG(SSSDBG_CRIT_FAILURE, + ("Invalid settings for range selection: [%d][%d][%d]\n", + idmap_lower, idmap_upper, rangesize)); + return EINVAL; + } + + max_slices = (idmap_upper - idmap_lower + 1) / rangesize; + if (((idmap_upper - idmap_lower + 1) % rangesize) != 0) { + DEBUG(SSSDBG_CONF_SETTINGS, + ("Range size does not divide evenly. Uppermost range will " + "not be used\n")); + } + + new_slice = talloc_zero(idmap_ctx, struct sdap_idmap_slice); + if (!new_slice) return ENOMEM; + + if (slice != -1) { + /* The slice is being set explicitly. + * This may happen at system startup when we're loading + * previously-determined slices. In the future, we may also + * permit configuration to select the slice for a domain + * explicitly. + */ + new_slice->slice_num = slice; + } else { + /* If slice is -1, we're being asked to pick a new slice */ + + /* Hash the domain sid string */ + hash_val = murmurhash3(dom_sid, strlen(dom_sid), 0xdeadbeef); + + /* Now get take the modulus of the hash val and the max_slices + * to determine its optimal position in the range. + */ + new_slice->slice_num = hash_val % max_slices; + orig_slice = new_slice->slice_num; + + /* Verify that this slice is not already in use */ + do { + DLIST_FOR_EACH(s, idmap_ctx->slices) { + if (s->slice_num == new_slice->slice_num) { + /* This slice number matches one already registered + * We'll try the next available slot + */ + new_slice->slice_num++; + if (new_slice->slice_num > max_slices) { + /* loop around to the beginning if necessary */ + new_slice->slice_num = 0; + } + break; + } + } + + /* Keep trying until s is NULL (meaning we got to the end + * without matching) or we have run out of slices and gotten + * back to the first one we tried. + */ + } while (s && new_slice->slice_num != orig_slice); + + if (s) { + /* We looped all the way through and found no empty slots */ + DEBUG(SSSDBG_CRIT_FAILURE, + ("Could not add domain [%s]: no free slices\n", + dom_name)); + ret = ENOSPC; + goto done; + } + } + + DEBUG(SSSDBG_CONF_SETTINGS, + ("Adding domain [%s] as slice [%d]\n", + dom_name, new_slice->slice_num)); + + DLIST_ADD_END(idmap_ctx->slices, new_slice, struct sdap_idmap_slice *); + /* Not adding a destructor to remove from this list, because it + * should never be possible. Removal from this list can only + * destabilize the system. + */ + + /* Create a range object to add to the mapping */ + range.min = (rangesize * new_slice->slice_num) + idmap_lower; + range.max = range.min + rangesize; + + if (range.max > idmap_upper) { + /* This should never happen */ + DEBUG(SSSDBG_CRIT_FAILURE, + ("BUG: Range maximum exceeds the global maximum: %d > %d\n", + range.max, idmap_upper)); + ret = EINVAL; + goto done; + } + + /* Add this domain to the map */ + err = sss_idmap_add_domain(idmap_ctx->map, dom_name, dom_sid, &range); + if (err != IDMAP_SUCCESS) { + DEBUG(SSSDBG_CRIT_FAILURE, + ("Could not add domain [%s] to the map: [%d]\n", + dom_name, err)); + ret = EIO; + goto done; + } + + /* Add this domain to the SYSDB cache so it will survive reboot */ + ret = sysdb_idmap_store_mapping(idmap_ctx->id_ctx->be->sysdb, + dom_name, dom_sid, + new_slice->slice_num); +done: + if (ret != EOK) { + talloc_free(new_slice); + } + return ret; +} diff --git a/src/providers/ldap/sdap_idmap.h b/src/providers/ldap/sdap_idmap.h new file mode 100644 index 000000000..9ac8be133 --- /dev/null +++ b/src/providers/ldap/sdap_idmap.h @@ -0,0 +1,52 @@ +/* + SSSD + + Authors: + Stephen Gallagher + + Copyright (C) 2012 Red Hat + + 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 . +*/ + +#ifndef SDAP_IDMAP_H_ +#define SDAP_IDMAP_H_ + +#include "src/providers/ldap/sdap.h" +#include "src/providers/ldap/ldap_common.h" + +struct sdap_idmap_slice { + struct sdap_idmap_slice *prev; + struct sdap_idmap_slice *next; + + id_t slice_num; +}; + +struct sdap_idmap_ctx { + struct sss_idmap_ctx *map; + struct sdap_idmap_slice *slices; + + struct sdap_id_ctx *id_ctx; +}; + +errno_t sdap_idmap_init(TALLOC_CTX *mem_ctx, + struct sdap_id_ctx *id_ctx, + struct sdap_idmap_ctx **_idmap_ctx); + +errno_t +sdap_idmap_add_domain(struct sdap_idmap_ctx *idmap_ctx, + const char *dom_name, + const char *dom_sid, + id_t slice); +#endif /* SDAP_IDMAP_H_ */ -- cgit