X-Git-Url: https://wimlib.net/git/?p=wimlib;a=blobdiff_plain;f=src%2Fsecurity.c;h=9c55ef2d30d09f0c5d6da72d3c64a8c7c2c9f05a;hp=c9158545f461fe74b2ce3e476de05f53920c104c;hb=ebd6c0ec0ff47ac18af4ef918fd78fb8d9f19540;hpb=0541069de2f74283d44ebb02372b60fb608795f2 diff --git a/src/security.c b/src/security.c index c9158545..9c55ef2d 100644 --- a/src/security.c +++ b/src/security.c @@ -1,13 +1,11 @@ /* * security.c * - * Read and write the WIM security data. The security data is a table of - * security descriptors. Each WIM image has its own security data, but it's - * possible that an image's security data have no security descriptors. + * Read and write the per-WIM-image table of security descriptors. */ /* - * Copyright (C) 2012 Eric Biggers + * Copyright (C) 2012, 2013 Eric Biggers * * This file is part of wimlib, a library for working with WIM files. * @@ -26,9 +24,226 @@ */ #include "wimlib_internal.h" -#include "io.h" +#include "buffer_io.h" #include "security.h" + +#define SECURITY_DESCRIPTOR_REVISION 1 +#define SECURITY_DESCRIPTOR_REVISION1 1 + +/* inherit AceFlags */ +#define OBJECT_INHERIT_ACE 0x01 +#define CONTAINER_INHERIT_ACE 0x02 +#define NO_PROPAGATE_INHERIT_ACE 0x04 +#define INHERIT_ONLY_ACE 0x08 +#define INHERITED_ACE 0x10 +#define VALID_INHERIT_FLAGS 0x1F + +#define SE_OWNER_DEFAULTED 0x00000001 +#define SE_GROUP_DEFAULTED 0x00000002 +#define SE_DACL_PRESENT 0x00000004 +#define SE_DACL_DEFAULTED 0x00000008 +#define SE_SACL_PRESENT 0x00000010 +#define SE_SACL_DEFAULTED 0x00000020 +#define SE_DACL_AUTO_INHERIT_REQ 0x00000100 +#define SE_SACL_AUTO_INHERIT_REQ 0x00000200 +#define SE_DACL_AUTO_INHERITED 0x00000400 +#define SE_SACL_AUTO_INHERITED 0x00000800 +#define SE_DACL_PROTECTED 0x00001000 +#define SE_SACL_PROTECTED 0x00002000 +#define SE_RM_CONTROL_VALID 0x00004000 +#define SE_SELF_RELATIVE 0x00008000 + +/* Flags in access control entries */ +#define DELETE 0x00010000 +#define READ_CONTROL 0x00020000 +#define WRITE_DAC 0x00040000 +#define WRITE_OWNER 0x00080000 +#define SYNCHRONIZE 0x00100000 +#define STANDARD_RIGHTS_REQUIRED 0x000f0000 + +#define STANDARD_RIGHTS_READ READ_CONTROL +#define STANDARD_RIGHTS_WRITE READ_CONTROL +#define STANDARD_RIGHTS_EXECUTE READ_CONTROL + +#define STANDARD_RIGHTS_ALL 0x001f0000 + +#define SPECIFIC_RIGHTS_ALL 0x0000ffff + +#define GENERIC_READ 0x80000000 +#define GENERIC_WRITE 0x40000000 +#define GENERIC_EXECUTE 0x20000000 +#define GENERIC_ALL 0x10000000 + +#define MAXIMUM_ALLOWED 0x02000000 +#define ACCESS_SYSTEM_SECURITY 0x01000000 + +#define EVENT_QUERY_STATE 0x0001 +#define EVENT_MODIFY_STATE 0x0002 +#define EVENT_ALL_ACCESS (STANDARD_RIGHTS_REQUIRED|SYNCHRONIZE|0x3) + +#define SEMAPHORE_MODIFY_STATE 0x0002 +#define SEMAPHORE_ALL_ACCESS (STANDARD_RIGHTS_REQUIRED|SYNCHRONIZE|0x3) + +#define MUTEX_MODIFY_STATE 0x0001 +#define MUTEX_ALL_ACCESS (STANDARD_RIGHTS_REQUIRED|SYNCHRONIZE|0x1) + +#define JOB_OBJECT_ASSIGN_PROCESS 0x0001 +#define JOB_OBJECT_SET_ATTRIBUTES 0x0002 +#define JOB_OBJECT_QUERY 0x0004 +#define JOB_OBJECT_TERMINATE 0x0008 +#define JOB_OBJECT_SET_SECURITY_ATTRIBUTES 0x0010 +#define JOB_OBJECT_ALL_ACCESS (STANDARD_RIGHTS_REQUIRED|SYNCHRONIZE|0x1f) + +#define TIMER_QUERY_STATE 0x0001 +#define TIMER_MODIFY_STATE 0x0002 +#define TIMER_ALL_ACCESS (STANDARD_RIGHTS_REQUIRED|SYNCHRONIZE|0x3) + +#define PROCESS_TERMINATE 0x0001 +#define PROCESS_CREATE_THREAD 0x0002 +#define PROCESS_VM_OPERATION 0x0008 +#define PROCESS_VM_READ 0x0010 +#define PROCESS_VM_WRITE 0x0020 +#define PROCESS_DUP_HANDLE 0x0040 +#define PROCESS_CREATE_PROCESS 0x0080 +#define PROCESS_SET_QUOTA 0x0100 +#define PROCESS_SET_INFORMATION 0x0200 +#define PROCESS_QUERY_INFORMATION 0x0400 +#define PROCESS_SUSPEND_RESUME 0x0800 +#define PROCESS_QUERY_LIMITED_INFORMATION 0x1000 +#define PROCESS_ALL_ACCESS (STANDARD_RIGHTS_REQUIRED|SYNCHRONIZE|0xfff) + +#define THREAD_TERMINATE 0x0001 +#define THREAD_SUSPEND_RESUME 0x0002 +#define THREAD_GET_CONTEXT 0x0008 +#define THREAD_SET_CONTEXT 0x0010 +#define THREAD_SET_INFORMATION 0x0020 +#define THREAD_QUERY_INFORMATION 0x0040 +#define THREAD_SET_THREAD_TOKEN 0x0080 +#define THREAD_IMPERSONATE 0x0100 +#define THREAD_DIRECT_IMPERSONATION 0x0200 +#define THREAD_ALL_ACCESS (STANDARD_RIGHTS_REQUIRED|SYNCHRONIZE|0x3ff) + +#define THREAD_BASE_PRIORITY_LOWRT 15 +#define THREAD_BASE_PRIORITY_MAX 2 +#define THREAD_BASE_PRIORITY_MIN -2 +#define THREAD_BASE_PRIORITY_IDLE -15 + +/* predefined authority values for SID's (security identifiers) */ +enum sid_authority_value { + SECURITY_NULL_SID_AUTHORITY = 0, + SECURITY_WORLD_SID_AUTHORITY = 1, + SECURITY_LOCAL_SID_AUTHORITY = 2, + SECURITY_CREATOR_SID_AUTHORITY = 3, + SECURITY_NON_UNIQUE_AUTHORITY = 4, + SECURITY_NT_AUTHORITY = 5, +}; + +/* local administrators group */ +#define SECURITY_BUILTIN_DOMAIN_RID 32 +#define DOMAIN_ALIAS_RID_ADMINS 544 + +/* See ACEHeader. */ +enum ace_type { + ACCESS_ALLOWED_ACE_TYPE = 0, + ACCESS_DENIED_ACE_TYPE = 1, + SYSTEM_AUDIT_ACE_TYPE = 2, +}; + +/* 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; + /* * This is a hack to work around a problem in libntfs-3g. libntfs-3g validates * security descriptors with a function named ntfs_valid_descr(). @@ -57,7 +272,7 @@ static void empty_sacl_fixup(u8 *descr, u64 *size_p) * * @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 + * @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 @@ -74,6 +289,8 @@ int read_security_data(const u8 metadata_resource[], u64 metadata_resource_len, int ret; u64 total_len; + wimlib_assert(metadata_resource_len >= 8); + /* * Sorry this function is excessively complicated--- I'm just being * extremely careful about integer overflows. @@ -121,7 +338,9 @@ int read_security_data(const u8 metadata_resource[], u64 metadata_resource_len, sd->num_entries, sd->total_length); if (sd->num_entries == 0) { - /* No security descriptors. */ + /* 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); @@ -135,14 +354,11 @@ int read_security_data(const u8 metadata_resource[], u64 metadata_resource_len, 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 must be at least %"PRIu64" bytes of security data", + "there seem to be at least %"PRIu64" bytes of security data", sd->total_length, 8 + sizes_size); goto out_invalid_sd; } - if (sizeof(size_t) < 8 && sizes_size > 0xffffffff) { - ERROR("Too many security descriptors!"); - goto out_invalid_sd; - } + sd->sizes = MALLOC(sizes_size); if (!sd->sizes) { ret = WIMLIB_ERR_NOMEM; @@ -174,14 +390,15 @@ int read_security_data(const u8 metadata_resource[], u64 metadata_resource_len, goto out_invalid_sd; } total_len += sd->sizes[i]; - /* This check assures that the descriptor size fits in a 32 bit + /* 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 are at least %"PRIu64" bytes of " - "security data", sd->total_length, total_len); + "because there seem to be at least %"PRIu64" " + "bytes of security data", + sd->total_length, total_len); goto out_invalid_sd; } sd->descriptors[i] = MALLOC(sd->sizes[i]); @@ -250,7 +467,7 @@ static void print_acl(const u8 *p, const char *type) printf(" ACE Count = %u\n", ace_count); p += sizeof(ACL); - for (uint i = 0; i < acl->ace_count; i++) { + for (u16 i = 0; i < ace_count; i++) { const ACEHeader *hdr = (const ACEHeader*)p; printf(" [ACE]\n"); printf(" ACE type = %d\n", hdr->type); @@ -274,7 +491,7 @@ static void print_sid(const u8 *p, const char *type) print_byte_field(sid->identifier_authority, sizeof(sid->identifier_authority)); putchar('\n'); - for (uint i = 0; i < sid->sub_authority_count; i++) + for (u8 i = 0; i < sid->sub_authority_count; i++) printf(" Subauthority %u = %u\n", i, le32_to_cpu(sid->sub_authority[i])); putchar('\n'); @@ -342,3 +559,131 @@ void free_security_data(struct wim_security_data *sd) } } } + +#if defined(WITH_NTFS_3G) || defined(__CYGWIN__) || defined(__WIN32__) +struct sd_node { + int security_id; + u8 hash[SHA1_HASH_SIZE]; + struct rb_node rb_node; +}; + +static void free_sd_tree(struct rb_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)); + } +} + +/* Frees a security descriptor index set. */ +void destroy_sd_set(struct sd_set *sd_set) +{ + free_sd_tree(sd_set->rb_root.rb_node); +} + +/* Inserts a a new node into the security descriptor index tree. */ +static void insert_sd_node(struct sd_set *set, struct sd_node *new) +{ + 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); +} + +/* 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]) +{ + 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; +} + +/* + * Adds a security descriptor to the indexed security descriptor set as well as + * the corresponding `struct wim_security_data', and returns the new security + * ID; or, if there is an existing security descriptor that is the same, return + * 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) +{ + u8 hash[SHA1_HASH_SIZE]; + int security_id; + struct sd_node *new; + u8 **descriptors; + u64 *sizes; + u8 *descr_copy; + struct wim_security_data *sd; + + sha1_buffer((const u8*)descriptor, size, hash); + + security_id = lookup_sd(sd_set, hash); + if (security_id >= 0) /* Identical descriptor already exists */ + return security_id; + + /* Need to add a new security descriptor */ + new = MALLOC(sizeof(*new)); + if (!new) + goto out; + descr_copy = MALLOC(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); + + descriptors = REALLOC(sd->descriptors, + (sd->num_entries + 1) * sizeof(sd->descriptors[0])); + if (!descriptors) + goto out_free_descr; + sd->descriptors = descriptors; + sizes = REALLOC(sd->sizes, + (sd->num_entries + 1) * sizeof(sd->sizes[0])); + if (!sizes) + goto out_free_descr; + sd->sizes = sizes; + 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; +out_free_descr: + FREE(descr_copy); +out_free_node: + FREE(new); +out: + return -1; +} +#endif /* WITH_NTFS_3G || __CYGWIN__ || __WIN32__ */