X-Git-Url: https://wimlib.net/git/?p=wimlib;a=blobdiff_plain;f=src%2Fsecurity.c;h=85cfb5bc6ce968f85671672577bd0c3984a69e41;hp=37b9a063cfe5bec6d4793fe2586a54427f5654fc;hb=d31b2fee211b1c31420bafe1c2379f6f89bd92fe;hpb=f8698b9c814a62a117982701b9551f699553b2a4 diff --git a/src/security.c b/src/security.c index 37b9a063..85cfb5bc 100644 --- a/src/security.c +++ b/src/security.c @@ -5,202 +5,100 @@ */ /* - * Copyright (C) 2012, 2013 Eric Biggers + * Copyright (C) 2012, 2013, 2014 Eric Biggers * - * This file is part of wimlib, a library for working with WIM files. + * This file is free software; you can redistribute it and/or modify it under + * the terms of the GNU Lesser General Public License as published by the Free + * Software Foundation; either version 3 of the License, or (at your option) any + * later version. * - * wimlib 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. - * - * wimlib 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 + * This file 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 Lesser General Public License for more * details. * - * You should have received a copy of the GNU General Public License - * along with wimlib; if not, see http://www.gnu.org/licenses/. + * You should have received a copy of the GNU Lesser General Public License + * along with this file; if not, see http://www.gnu.org/licenses/. */ -#include "wimlib_internal.h" -#include "buffer_io.h" -#include "security.h" - -/* At the start of each type of access control entry. */ -typedef struct { - /* enum ace_type, specifies what type of ACE this is. */ - u8 type; - - /* bitwise OR of the inherit ACE flags #defined above */ - u8 flags; - - /* Size of the access control entry. */ - u8 size; -} ACEHeader; - -/* Grants rights to a user or group */ -typedef struct { - ACEHeader hdr; - u32 mask; - u32 sid_start; -} AccessAllowedACE; - -/* Denies rights to a user or group */ -typedef struct { - ACEHeader hdr; - u32 mask; - u32 sid_start; -} AccessDeniedACE; - -typedef struct { - ACEHeader hdr; - u32 mask; - u32 sid_start; -} SystemAuditACE; - - -/* Header of an access control list. */ -typedef struct { - /* ACL_REVISION or ACL_REVISION_DS */ - u8 revision; - - /* padding */ - u8 sbz1; - - /* Total size of the ACL, including all access control entries */ - u16 acl_size; - - /* Number of access control entry structures that follow the ACL - * structure. */ - u16 ace_count; - - /* padding */ - u16 sbz2; -} ACL; - -/* A structure used to identify users or groups. */ -typedef struct { - - /* example: 0x1 */ - u8 revision; - u8 sub_authority_count; - - /* Identifies the authority that issued the SID. Can be, but does not - * have to be, one of enum sid_authority_value */ - u8 identifier_authority[6]; - - u32 sub_authority[0]; -} SID; - - -typedef struct { - /* Example: 0x1 */ - u8 revision; - /* Example: 0x0 */ - u8 sbz1; - /* Example: 0x4149 */ - u16 security_descriptor_control; - - /* Offset of a SID structure in the security descriptor. */ - /* Example: 0x14 */ - u32 owner_offset; - - /* Offset of a SID structure in the security descriptor. */ - /* Example: 0x24 */ - u32 group_offset; - - /* Offset of an ACL structure in the security descriptor. */ - /* System ACL. */ - /* Example: 0x00 */ - u32 sacl_offset; - - /* Offset of an ACL structure in the security descriptor. */ - /* Discretionary ACL. */ - /* Example: 0x34 */ - u32 dacl_offset; -} SecurityDescriptor; +#ifdef HAVE_CONFIG_H +# include "config.h" +#endif -/* - * This is a hack to work around a problem in libntfs-3g. libntfs-3g validates - * security descriptors with a function named ntfs_valid_descr(). - * ntfs_valid_descr() considers a security descriptor that ends in a SACL - * (Sysetm Access Control List) with no ACE's (Access Control Entries) to be - * invalid. However, a security descriptor like this exists in the Windows 7 - * install.wim. Here, security descriptors matching this pattern are modified - * to have no SACL. This should make no difference since the SACL had no - * entries anyway; however this ensures that that the security descriptors pass - * the validation in libntfs-3g. - */ -static void -empty_sacl_fixup(u8 *descr, u64 *size_p) +#include "wimlib/assert.h" +#include "wimlib/avl_tree.h" +#include "wimlib/endianness.h" +#include "wimlib/error.h" +#include "wimlib/security.h" +#include "wimlib/sha1.h" +#include "wimlib/util.h" + +struct wim_security_data_disk { + le32 total_length; + le32 num_entries; + le64 sizes[]; +} _packed_attribute; + +struct wim_security_data * +new_wim_security_data(void) { - /* No-op if no NTFS-3g support, or if NTFS-3g is version 2013 or later - * */ -#if defined(WITH_NTFS_3G) && !defined(HAVE_NTFS_MNT_RDONLY) - if (*size_p >= sizeof(SecurityDescriptor)) { - SecurityDescriptor *sd = (SecurityDescriptor*)descr; - u32 sacl_offset = le32_to_cpu(sd->sacl_offset); - if (sacl_offset == *size_p - sizeof(ACL)) { - sd->sacl_offset = cpu_to_le32(0); - *size_p -= sizeof(ACL); - } - } -#endif + return CALLOC(1, sizeof(struct wim_security_data)); } /* - * Reads the security data from the metadata resource. + * Reads the security data from the metadata resource of a WIM image. * - * @metadata_resource: An array that contains the uncompressed metadata - * resource for the WIM file. - * @metadata_resource_len: The length of @metadata_resource. It must be at - * least 8 bytes. - * @sd_p: A pointer to a pointer to a wim_security_data structure that - * will be filled in with a pointer to a new wim_security_data - * structure on success. + * @buf + * Buffer containing an uncompressed WIM metadata resource. + * @buf_len + * Length of the uncompressed metadata resource, in bytes. + * @sd_ret + * On success, a pointer to the resulting security data structure will be + * returned here. * * Note: There is no `offset' argument because the security data is located at * the beginning of the metadata resource. + * + * Return values: + * WIMLIB_ERR_SUCCESS (0) + * WIMLIB_ERR_INVALID_METADATA_RESOURCE + * WIMLIB_ERR_NOMEM */ int -read_security_data(const u8 metadata_resource[], u64 metadata_resource_len, - struct wim_security_data **sd_p) +read_wim_security_data(const u8 *buf, size_t buf_len, + struct wim_security_data **sd_ret) { struct wim_security_data *sd; - const u8 *p; int ret; u64 total_len; + u64 sizes_size; + u64 size_no_descriptors; + const struct wim_security_data_disk *sd_disk; + const u8 *p; - wimlib_assert(metadata_resource_len >= 8); + if (buf_len < 8) + return WIMLIB_ERR_INVALID_METADATA_RESOURCE; - /* - * Sorry this function is excessively complicated--- I'm just being - * extremely careful about integer overflows. - */ + sd = new_wim_security_data(); + if (!sd) + goto out_of_memory; - sd = MALLOC(sizeof(struct wim_security_data)); - if (!sd) { - ERROR("Out of memory"); - return WIMLIB_ERR_NOMEM; - } - sd->sizes = NULL; - sd->descriptors = NULL; - sd->refcnt = 1; + sd_disk = (const struct wim_security_data_disk *)buf; + sd->total_length = ALIGN(le32_to_cpu(sd_disk->total_length), 8); + sd->num_entries = le32_to_cpu(sd_disk->num_entries); - p = metadata_resource; - p = get_u32(p, &sd->total_length); - p = get_u32(p, (u32*)&sd->num_entries); + /* Length field of 0 is a special case that really means length + * of 8. */ + if (sd->total_length == 0) + sd->total_length = 8; /* The security_id field of each dentry is a signed 32-bit integer, so * the possible indices into the security descriptors table are 0 * through 0x7fffffff. Which means 0x80000000 security descriptors * maximum. Not like you should ever have anywhere close to that many * security descriptors! */ - if (sd->num_entries > 0x80000000) { - ERROR("Security data has too many entries!"); + if (sd->num_entries > 0x80000000) goto out_invalid_sd; - } /* Verify the listed total length of the security data is big enough to * include the sizes array, verify that the file data is big enough to @@ -210,312 +108,184 @@ read_security_data(const u8 metadata_resource[], u64 metadata_resource_len, * integer, even though each security descriptor size is a 64-bit * integer. This is stupid, and we need to be careful not to actually * let the security descriptor sizes be over 0xffffffff. */ - if ((u64)sd->total_length > metadata_resource_len) { - ERROR("Security data total length (%u) is bigger than the " - "metadata resource length (%"PRIu64")", - sd->total_length, metadata_resource_len); + if (sd->total_length > buf_len) goto out_invalid_sd; - } - DEBUG("Reading security data: %u entries, length = %u", - sd->num_entries, sd->total_length); + sizes_size = (u64)sd->num_entries * sizeof(u64); + size_no_descriptors = 8 + sizes_size; + if (size_no_descriptors > sd->total_length) + goto out_invalid_sd; - if (sd->num_entries == 0) { - /* No security descriptors. We allow the total_length field to - * be either 8 (which is correct, since there are always 2 - * 32-bit integers) or 0. */ - if (sd->total_length != 0 && sd->total_length != 8) { - ERROR("Invalid security data length (%u): expected 0 or 8", - sd->total_length); - goto out_invalid_sd; - } - sd->total_length = 8; - goto out_return_sd; - } + total_len = size_no_descriptors; - u64 sizes_size = (u64)sd->num_entries * sizeof(u64); - u64 size_no_descriptors = 8 + sizes_size; - if (size_no_descriptors > (u64)sd->total_length) { - ERROR("Security data total length of %u is too short because " - "there seem to be at least %"PRIu64" bytes of security data", - sd->total_length, 8 + sizes_size); - goto out_invalid_sd; - } + /* Return immediately if no security descriptors. */ + if (sd->num_entries == 0) + goto out_descriptors_ready; + /* Allocate a new buffer for the sizes array */ sd->sizes = MALLOC(sizes_size); - if (!sd->sizes) { - ret = WIMLIB_ERR_NOMEM; - goto out_free_sd; - } + if (!sd->sizes) + goto out_of_memory; - /* Copy the sizes array in from the file data. */ - p = get_bytes(p, sizes_size, sd->sizes); - array_le64_to_cpu(sd->sizes, sd->num_entries); - - /* Allocate the array of pointers to descriptors, and read them in. */ - sd->descriptors = CALLOC(sd->num_entries, sizeof(u8*)); - if (!sd->descriptors) { - ERROR("Out of memory while allocating security " - "descriptors"); - ret = WIMLIB_ERR_NOMEM; - goto out_free_sd; + /* Copy the sizes array into the new buffer */ + for (u32 i = 0; i < sd->num_entries; i++) { + sd->sizes[i] = le64_to_cpu(sd_disk->sizes[i]); + if (sd->sizes[i] > 0xffffffff) + goto out_invalid_sd; } - total_len = size_no_descriptors; + + p = (const u8*)sd_disk + size_no_descriptors; + + /* Allocate the array of pointers to the security descriptors, then read + * them into separate buffers. */ + sd->descriptors = CALLOC(sd->num_entries, sizeof(sd->descriptors[0])); + if (!sd->descriptors) + goto out_of_memory; for (u32 i = 0; i < sd->num_entries; i++) { - /* Watch out for huge security descriptor sizes that could - * overflow the total length and wrap it around. */ - if (total_len + sd->sizes[i] < total_len) { - ERROR("Caught overflow in security descriptor lengths " - "(current total length = %"PRIu64", security " - "descriptor size = %"PRIu64")", - total_len, sd->sizes[i]); - goto out_invalid_sd; - } + if (sd->sizes[i] == 0) + continue; total_len += sd->sizes[i]; - /* This check ensures that the descriptor size fits in a 32 bit - * integer. Because if it didn't, the total length would come - * out bigger than sd->total_length, which is a 32 bit integer. - * */ - if (total_len > (u64)sd->total_length) { - ERROR("Security data total length of %u is too short " - "because there seem to be at least %"PRIu64" " - "bytes of security data", - sd->total_length, total_len); + if (total_len > (u64)sd->total_length) goto out_invalid_sd; - } - sd->descriptors[i] = MALLOC(sd->sizes[i]); - if (!sd->descriptors[i]) { - ERROR("Out of memory while allocating security " - "descriptors"); - ret = WIMLIB_ERR_NOMEM; - goto out_free_sd; - } - p = get_bytes(p, sd->sizes[i], sd->descriptors[i]); - empty_sacl_fixup(sd->descriptors[i], &sd->sizes[i]); + sd->descriptors[i] = memdup(p, sd->sizes[i]); + if (!sd->descriptors[i]) + goto out_of_memory; + p += sd->sizes[i]; } - wimlib_assert(total_len <= 0xffffffff); - if (((total_len + 7) & ~7) != ((sd->total_length + 7) & ~7)) { - ERROR("Expected security data total length = %u, but " - "calculated %u", sd->total_length, (unsigned)total_len); - goto out_invalid_sd; +out_descriptors_ready: + if (ALIGN(total_len, 8) != sd->total_length) { + WARNING("Stored WIM security data total length was " + "%"PRIu32" bytes, but calculated %"PRIu32" bytes", + sd->total_length, (u32)total_len); } - sd->total_length = total_len; -out_return_sd: - *sd_p = sd; - return 0; + *sd_ret = sd; + ret = 0; + goto out; out_invalid_sd: - ret = WIMLIB_ERR_INVALID_SECURITY_DATA; + ERROR("WIM security data is invalid!"); + ret = WIMLIB_ERR_INVALID_METADATA_RESOURCE; + goto out_free_sd; +out_of_memory: + ERROR("Out of memory while reading WIM security data!"); + ret = WIMLIB_ERR_NOMEM; out_free_sd: - free_security_data(sd); + free_wim_security_data(sd); +out: return ret; } /* - * Writes security data to an in-memory buffer. + * Writes the security data for a WIM image to an in-memory buffer. */ u8 * -write_security_data(const struct wim_security_data *sd, u8 *p) +write_wim_security_data(const struct wim_security_data * restrict sd, + u8 * restrict p) { - DEBUG("Writing security data (total_length = %"PRIu32", num_entries " - "= %"PRIu32")", sd->total_length, sd->num_entries); - - u32 aligned_length = (sd->total_length + 7) & ~7; - u8 *orig_p = p; - p = put_u32(p, aligned_length); - p = put_u32(p, sd->num_entries); - - for (u32 i = 0; i < sd->num_entries; i++) - p = put_u64(p, sd->sizes[i]); - - for (u32 i = 0; i < sd->num_entries; i++) - p = put_bytes(p, sd->sizes[i], sd->descriptors[i]); - - wimlib_assert(p - orig_p == sd->total_length); - p = put_zeroes(p, aligned_length - sd->total_length); + struct wim_security_data_disk *sd_disk = (struct wim_security_data_disk*)p; + u32 num_entries = sd->num_entries; - DEBUG("Successfully wrote security data."); - return p; -} + sd_disk->total_length = cpu_to_le32(sd->total_length); + sd_disk->num_entries = cpu_to_le32(num_entries); -static void -print_acl(const void *p, const tchar *type) -{ - const ACL *acl = p; - u8 revision = acl->revision; - u16 acl_size = le16_to_cpu(acl->acl_size); - u16 ace_count = le16_to_cpu(acl->ace_count); - tprintf(T(" [%"TS" ACL]\n"), type); - tprintf(T(" Revision = %u\n"), revision); - tprintf(T(" ACL Size = %u\n"), acl_size); - tprintf(T(" ACE Count = %u\n"), ace_count); - - p += sizeof(ACL); - for (u16 i = 0; i < ace_count; i++) { - const ACEHeader *hdr = p; - tprintf(T(" [ACE]\n")); - tprintf(T(" ACE type = %d\n"), hdr->type); - tprintf(T(" ACE flags = 0x%x\n"), hdr->flags); - tprintf(T(" ACE size = %u\n"), hdr->size); - const AccessAllowedACE *aaa = (const AccessAllowedACE*)hdr; - tprintf(T(" ACE mask = %x\n"), le32_to_cpu(aaa->mask)); - tprintf(T(" SID start = %u\n"), le32_to_cpu(aaa->sid_start)); - p += hdr->size; - } - tputchar(T('\n')); -} - -static void -print_sid(const void *p, const tchar *type) -{ - const SID *sid = p; - tprintf(T(" [%"TS" SID]\n"), type); - tprintf(T(" Revision = %u\n"), sid->revision); - tprintf(T(" Subauthority count = %u\n"), sid->sub_authority_count); - tprintf(T(" Identifier authority = ")); - print_byte_field(sid->identifier_authority, - sizeof(sid->identifier_authority), stdout); - tputchar(T('\n')); - for (u8 i = 0; i < sid->sub_authority_count; i++) { - tprintf(T(" Subauthority %u = %u\n"), - i, le32_to_cpu(sid->sub_authority[i])); - } - tputchar(T('\n')); -} + for (u32 i = 0; i < num_entries; i++) + sd_disk->sizes[i] = cpu_to_le64(sd->sizes[i]); -static void -print_security_descriptor(const void *p, u64 size) -{ - const SecurityDescriptor *sd = p; - - u8 revision = sd->revision; - u16 control = le16_to_cpu(sd->security_descriptor_control); - u32 owner_offset = le32_to_cpu(sd->owner_offset); - u32 group_offset = le32_to_cpu(sd->group_offset); - u32 sacl_offset = le32_to_cpu(sd->sacl_offset); - u32 dacl_offset = le32_to_cpu(sd->dacl_offset); - tprintf(T("Revision = %u\n"), revision); - tprintf(T("Security Descriptor Control = %#x\n"), control); - tprintf(T("Owner offset = %u\n"), owner_offset); - tprintf(T("Group offset = %u\n"), group_offset); - tprintf(T("System ACL offset = %u\n"), sacl_offset); - tprintf(T("Discretionary ACL offset = %u\n"), dacl_offset); - - if (sd->owner_offset != 0) - print_sid(p + owner_offset, T("Owner")); - if (sd->group_offset != 0) - print_sid(p + group_offset, T("Group")); - if (sd->sacl_offset != 0) - print_acl(p + sacl_offset, T("System")); - if (sd->dacl_offset != 0) - print_acl(p + dacl_offset, T("Discretionary")); -} + p = (u8*)&sd_disk->sizes[num_entries]; -/* - * Prints the security data for a WIM file. - */ -void -print_security_data(const struct wim_security_data *sd) -{ - wimlib_assert(sd != NULL); + for (u32 i = 0; i < num_entries; i++) + p = mempcpy(p, sd->descriptors[i], sd->sizes[i]); - tputs(T("[SECURITY DATA]")); - tprintf(T("Length = %"PRIu32" bytes\n"), sd->total_length); - tprintf(T("Number of Entries = %"PRIu32"\n"), sd->num_entries); + while ((uintptr_t)p & 7) + *p++ = 0; - for (u32 i = 0; i < sd->num_entries; i++) { - tprintf(T("[SecurityDescriptor %"PRIu32", length = %"PRIu64"]\n"), - i, sd->sizes[i]); - print_security_descriptor(sd->descriptors[i], sd->sizes[i]); - tputchar(T('\n')); - } - tputchar(T('\n')); + wimlib_assert(p - orig_p == sd->total_length); + return p; } void -free_security_data(struct wim_security_data *sd) +free_wim_security_data(struct wim_security_data *sd) { if (sd) { - wimlib_assert(sd->refcnt != 0); - if (--sd->refcnt == 0) { - u8 **descriptors = sd->descriptors; - u32 num_entries = sd->num_entries; - if (descriptors) - while (num_entries--) - FREE(*descriptors++); - FREE(sd->sizes); - FREE(sd->descriptors); - FREE(sd); - } + u8 **descriptors = sd->descriptors; + u32 num_entries = sd->num_entries; + if (descriptors) + while (num_entries--) + FREE(*descriptors++); + FREE(sd->sizes); + FREE(sd->descriptors); + FREE(sd); } } struct sd_node { - int security_id; + s32 security_id; u8 hash[SHA1_HASH_SIZE]; - struct rb_node rb_node; + struct avl_tree_node index_node; }; +#define SD_NODE(avl_node) \ + avl_tree_entry(avl_node, struct sd_node, index_node) + static void -free_sd_tree(struct rb_node *node) +free_sd_tree(struct avl_tree_node *node) { if (node) { - free_sd_tree(node->rb_left); - free_sd_tree(node->rb_right); - FREE(container_of(node, struct sd_node, rb_node)); + free_sd_tree(node->left); + free_sd_tree(node->right); + FREE(SD_NODE(node)); } } +void +rollback_new_security_descriptors(struct wim_sd_set *sd_set) +{ + struct wim_security_data *sd = sd_set->sd; + u8 **descriptors = sd->descriptors + sd_set->orig_num_entries; + u32 num_entries = sd->num_entries - sd_set->orig_num_entries; + while (num_entries--) + FREE(*descriptors++); + sd->num_entries = sd_set->orig_num_entries; +} + /* Frees a security descriptor index set. */ void -destroy_sd_set(struct sd_set *sd_set) +destroy_sd_set(struct wim_sd_set *sd_set) { - free_sd_tree(sd_set->rb_root.rb_node); + free_sd_tree(sd_set->root); } -/* Inserts a a new node into the security descriptor index tree. */ -static void -insert_sd_node(struct sd_set *set, struct sd_node *new) +static int +_avl_cmp_nodes_by_hash(const struct avl_tree_node *n1, + const struct avl_tree_node *n2) { - struct rb_root *root = &set->rb_root; - struct rb_node **p = &(root->rb_node); - struct rb_node *rb_parent = NULL; - - while (*p) { - struct sd_node *this = container_of(*p, struct sd_node, rb_node); - int cmp = hashes_cmp(new->hash, this->hash); - - rb_parent = *p; - if (cmp < 0) - p = &((*p)->rb_left); - else if (cmp > 0) - p = &((*p)->rb_right); - else - wimlib_assert(0); /* Duplicate SHA1 message digest */ - } - rb_link_node(&new->rb_node, rb_parent, p); - rb_insert_color(&new->rb_node, root); + return hashes_cmp(SD_NODE(n1)->hash, SD_NODE(n2)->hash); +} + +/* Inserts a new node into the security descriptor index tree. Returns true + * if successful (not a duplicate). */ +static bool +insert_sd_node(struct wim_sd_set *set, struct sd_node *new) +{ + return NULL == avl_tree_insert(&set->root, &new->index_node, + _avl_cmp_nodes_by_hash); } /* Returns the index of the security descriptor having a SHA1 message digest of * @hash. If not found, return -1. */ -int -lookup_sd(struct sd_set *set, const u8 hash[SHA1_HASH_SIZE]) +static s32 +lookup_sd(struct wim_sd_set *set, const u8 hash[SHA1_HASH_SIZE]) { - struct rb_node *node = set->rb_root.rb_node; - - while (node) { - struct sd_node *sd_node = container_of(node, struct sd_node, rb_node); - int cmp = hashes_cmp(hash, sd_node->hash); - if (cmp < 0) - node = node->rb_left; - else if (cmp > 0) - node = node->rb_right; - else - return sd_node->security_id; - } - return -1; + struct avl_tree_node *res; + struct sd_node dummy; + + copy_hash(dummy.hash, hash); + res = avl_tree_lookup_node(set->root, &dummy.index_node, + _avl_cmp_nodes_by_hash); + if (!res) + return -1; + return SD_NODE(res)->security_id; } /* @@ -525,37 +295,42 @@ lookup_sd(struct sd_set *set, const u8 hash[SHA1_HASH_SIZE]) * the security ID for it. If a new security descriptor cannot be allocated, * return -1. */ -int -sd_set_add_sd(struct sd_set *sd_set, const char descriptor[], size_t size) +s32 +sd_set_add_sd(struct wim_sd_set *sd_set, const char *descriptor, size_t size) { u8 hash[SHA1_HASH_SIZE]; - int security_id; + s32 security_id; struct sd_node *new; u8 **descriptors; u64 *sizes; u8 *descr_copy; struct wim_security_data *sd; + bool bret; - sha1_buffer((const u8*)descriptor, size, hash); + sha1_buffer(descriptor, size, hash); security_id = lookup_sd(sd_set, hash); if (security_id >= 0) /* Identical descriptor already exists */ - return security_id; + goto out; /* Need to add a new security descriptor */ + security_id = -1; + new = MALLOC(sizeof(*new)); if (!new) goto out; - descr_copy = MALLOC(size); + + descr_copy = memdup(descriptor, size); if (!descr_copy) goto out_free_node; sd = sd_set->sd; - - memcpy(descr_copy, descriptor, size); new->security_id = sd->num_entries; copy_hash(new->hash, hash); + /* There typically are only a few dozen security descriptors in a + * directory tree, so expanding the array of security descriptors by + * only 1 extra space each time should not be a problem. */ descriptors = REALLOC(sd->descriptors, (sd->num_entries + 1) * sizeof(sd->descriptors[0])); if (!descriptors) @@ -569,14 +344,49 @@ sd_set_add_sd(struct sd_set *sd_set, const char descriptor[], size_t size) sd->descriptors[sd->num_entries] = descr_copy; sd->sizes[sd->num_entries] = size; sd->num_entries++; - DEBUG("There are now %d security descriptors", sd->num_entries); - sd->total_length += size + sizeof(sd->sizes[0]); - insert_sd_node(sd_set, new); - return new->security_id; + bret = insert_sd_node(sd_set, new); + wimlib_assert(bret); + security_id = new->security_id; + goto out; out_free_descr: FREE(descr_copy); out_free_node: FREE(new); out: - return -1; + return security_id; +} + +/* Initialize a `struct sd_set' mapping from SHA1 message digests of security + * descriptors to indices into the security descriptors table of the WIM image + * (security IDs). */ +int +init_sd_set(struct wim_sd_set *sd_set, struct wim_security_data *sd) +{ + int ret; + + sd_set->sd = sd; + sd_set->root = NULL; + + /* Remember the original number of security descriptors so that newly + * added ones can be rolled back if needed. */ + sd_set->orig_num_entries = sd->num_entries; + for (u32 i = 0; i < sd->num_entries; i++) { + struct sd_node *new; + + new = MALLOC(sizeof(struct sd_node)); + if (!new) { + ret = WIMLIB_ERR_NOMEM; + goto out_destroy_sd_set; + } + sha1_buffer(sd->descriptors[i], sd->sizes[i], new->hash); + new->security_id = i; + if (!insert_sd_node(sd_set, new)) + FREE(new); /* Ignore duplicate security descriptor */ + } + ret = 0; + goto out; +out_destroy_sd_set: + destroy_sd_set(sd_set); +out: + return ret; }