diff options
author | James Bottomley <jejb@sparkweed.localdomain> | 2006-09-23 21:03:52 -0500 |
---|---|---|
committer | James Bottomley <jejb@sparkweed.localdomain> | 2006-09-23 21:03:52 -0500 |
commit | 1aedf2ccc60fade26c46fae12e28664d0da3f199 (patch) | |
tree | d91083e3079f1ddb942a382ac2b5a7525570ad59 /security/selinux/ss | |
parent | dfdc58ba354adb80d67c99f7be84f95a8e02e466 (diff) | |
parent | 1ab9dd0902df4f4ff56fbf672220549090ab28ba (diff) |
Merge mulgrave-w:git/linux-2.6
Conflicts:
include/linux/blkdev.h
Trivial merge to incorporate tag prototypes.
Diffstat (limited to 'security/selinux/ss')
-rw-r--r-- | security/selinux/ss/ebitmap.c | 140 | ||||
-rw-r--r-- | security/selinux/ss/ebitmap.h | 6 | ||||
-rw-r--r-- | security/selinux/ss/mls.c | 176 | ||||
-rw-r--r-- | security/selinux/ss/mls.h | 41 | ||||
-rw-r--r-- | security/selinux/ss/services.c | 613 |
5 files changed, 956 insertions, 20 deletions
diff --git a/security/selinux/ss/ebitmap.c b/security/selinux/ss/ebitmap.c index 47024a6e184..cfed1d30fa6 100644 --- a/security/selinux/ss/ebitmap.c +++ b/security/selinux/ss/ebitmap.c @@ -3,6 +3,14 @@ * * Author : Stephen Smalley, <sds@epoch.ncsc.mil> */ +/* + * Updated: Hewlett-Packard <paul.moore@hp.com> + * + * Added ebitmap_export() and ebitmap_import() + * + * (c) Copyright Hewlett-Packard Development Company, L.P., 2006 + */ + #include <linux/kernel.h> #include <linux/slab.h> #include <linux/errno.h> @@ -59,6 +67,138 @@ int ebitmap_cpy(struct ebitmap *dst, struct ebitmap *src) return 0; } +/** + * ebitmap_export - Export an ebitmap to a unsigned char bitmap string + * @src: the ebitmap to export + * @dst: the resulting bitmap string + * @dst_len: length of dst in bytes + * + * Description: + * Allocate a buffer at least src->highbit bits long and export the extensible + * bitmap into the buffer. The bitmap string will be in little endian format, + * i.e. LSB first. The value returned in dst_len may not the true size of the + * buffer as the length of the buffer is rounded up to a multiple of MAPTYPE. + * The caller must free the buffer when finished. Returns zero on success, + * negative values on failure. + * + */ +int ebitmap_export(const struct ebitmap *src, + unsigned char **dst, + size_t *dst_len) +{ + size_t bitmap_len; + unsigned char *bitmap; + struct ebitmap_node *iter_node; + MAPTYPE node_val; + size_t bitmap_byte; + unsigned char bitmask; + + bitmap_len = src->highbit / 8; + if (src->highbit % 7) + bitmap_len += 1; + if (bitmap_len == 0) + return -EINVAL; + + bitmap = kzalloc((bitmap_len & ~(sizeof(MAPTYPE) - 1)) + + sizeof(MAPTYPE), + GFP_ATOMIC); + if (bitmap == NULL) + return -ENOMEM; + + iter_node = src->node; + do { + bitmap_byte = iter_node->startbit / 8; + bitmask = 0x80; + node_val = iter_node->map; + do { + if (bitmask == 0) { + bitmap_byte++; + bitmask = 0x80; + } + if (node_val & (MAPTYPE)0x01) + bitmap[bitmap_byte] |= bitmask; + node_val >>= 1; + bitmask >>= 1; + } while (node_val > 0); + iter_node = iter_node->next; + } while (iter_node); + + *dst = bitmap; + *dst_len = bitmap_len; + return 0; +} + +/** + * ebitmap_import - Import an unsigned char bitmap string into an ebitmap + * @src: the bitmap string + * @src_len: the bitmap length in bytes + * @dst: the empty ebitmap + * + * Description: + * This function takes a little endian bitmap string in src and imports it into + * the ebitmap pointed to by dst. Returns zero on success, negative values on + * failure. + * + */ +int ebitmap_import(const unsigned char *src, + size_t src_len, + struct ebitmap *dst) +{ + size_t src_off = 0; + size_t node_limit; + struct ebitmap_node *node_new; + struct ebitmap_node *node_last = NULL; + u32 i_byte; + u32 i_bit; + unsigned char src_byte; + + while (src_off < src_len) { + if (src_len - src_off >= sizeof(MAPTYPE)) { + if (*(MAPTYPE *)&src[src_off] == 0) { + src_off += sizeof(MAPTYPE); + continue; + } + node_limit = sizeof(MAPTYPE); + } else { + for (src_byte = 0, i_byte = src_off; + i_byte < src_len && src_byte == 0; + i_byte++) + src_byte |= src[i_byte]; + if (src_byte == 0) + break; + node_limit = src_len - src_off; + } + + node_new = kzalloc(sizeof(*node_new), GFP_ATOMIC); + if (unlikely(node_new == NULL)) { + ebitmap_destroy(dst); + return -ENOMEM; + } + node_new->startbit = src_off * 8; + for (i_byte = 0; i_byte < node_limit; i_byte++) { + src_byte = src[src_off++]; + for (i_bit = i_byte * 8; src_byte != 0; i_bit++) { + if (src_byte & 0x80) + node_new->map |= MAPBIT << i_bit; + src_byte <<= 1; + } + } + + if (node_last != NULL) + node_last->next = node_new; + else + dst->node = node_new; + node_last = node_new; + } + + if (likely(node_last != NULL)) + dst->highbit = node_last->startbit + MAPSIZE; + else + ebitmap_init(dst); + + return 0; +} + int ebitmap_contains(struct ebitmap *e1, struct ebitmap *e2) { struct ebitmap_node *n1, *n2; diff --git a/security/selinux/ss/ebitmap.h b/security/selinux/ss/ebitmap.h index 8bf41055a6c..da2d4651b10 100644 --- a/security/selinux/ss/ebitmap.h +++ b/security/selinux/ss/ebitmap.h @@ -69,6 +69,12 @@ static inline int ebitmap_node_get_bit(struct ebitmap_node * n, int ebitmap_cmp(struct ebitmap *e1, struct ebitmap *e2); int ebitmap_cpy(struct ebitmap *dst, struct ebitmap *src); +int ebitmap_export(const struct ebitmap *src, + unsigned char **dst, + size_t *dst_len); +int ebitmap_import(const unsigned char *src, + size_t src_len, + struct ebitmap *dst); int ebitmap_contains(struct ebitmap *e1, struct ebitmap *e2); int ebitmap_get_bit(struct ebitmap *e, unsigned long bit); int ebitmap_set_bit(struct ebitmap *e, unsigned long bit, int value); diff --git a/security/selinux/ss/mls.c b/security/selinux/ss/mls.c index 7bc5b6440f7..119bd6078ba 100644 --- a/security/selinux/ss/mls.c +++ b/security/selinux/ss/mls.c @@ -10,6 +10,13 @@ * * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc. */ +/* + * Updated: Hewlett-Packard <paul.moore@hp.com> + * + * Added support to import/export the MLS label + * + * (c) Copyright Hewlett-Packard Development Company, L.P., 2006 + */ #include <linux/kernel.h> #include <linux/slab.h> @@ -212,26 +219,6 @@ int mls_context_isvalid(struct policydb *p, struct context *c) } /* - * Copies the MLS range from `src' into `dst'. - */ -static inline int mls_copy_context(struct context *dst, - struct context *src) -{ - int l, rc = 0; - - /* Copy the MLS range from the source context */ - for (l = 0; l < 2; l++) { - dst->range.level[l].sens = src->range.level[l].sens; - rc = ebitmap_cpy(&dst->range.level[l].cat, - &src->range.level[l].cat); - if (rc) - break; - } - - return rc; -} - -/* * Set the MLS fields in the security context structure * `context' based on the string representation in * the string `*scontext'. Update `*scontext' to @@ -585,3 +572,152 @@ int mls_compute_sid(struct context *scontext, return -EINVAL; } +/** + * mls_export_lvl - Export the MLS sensitivity levels + * @context: the security context + * @low: the low sensitivity level + * @high: the high sensitivity level + * + * Description: + * Given the security context copy the low MLS sensitivity level into lvl_low + * and the high sensitivity level in lvl_high. The MLS levels are only + * exported if the pointers are not NULL, if they are NULL then that level is + * not exported. + * + */ +void mls_export_lvl(const struct context *context, u32 *low, u32 *high) +{ + if (!selinux_mls_enabled) + return; + + if (low != NULL) + *low = context->range.level[0].sens - 1; + if (high != NULL) + *high = context->range.level[1].sens - 1; +} + +/** + * mls_import_lvl - Import the MLS sensitivity levels + * @context: the security context + * @low: the low sensitivity level + * @high: the high sensitivity level + * + * Description: + * Given the security context and the two sensitivty levels, set the MLS levels + * in the context according the two given as parameters. Returns zero on + * success, negative values on failure. + * + */ +void mls_import_lvl(struct context *context, u32 low, u32 high) +{ + if (!selinux_mls_enabled) + return; + + context->range.level[0].sens = low + 1; + context->range.level[1].sens = high + 1; +} + +/** + * mls_export_cat - Export the MLS categories + * @context: the security context + * @low: the low category + * @low_len: length of the cat_low bitmap in bytes + * @high: the high category + * @high_len: length of the cat_high bitmap in bytes + * + * Description: + * Given the security context export the low MLS category bitmap into cat_low + * and the high category bitmap into cat_high. The MLS categories are only + * exported if the pointers are not NULL, if they are NULL then that level is + * not exported. The caller is responsibile for freeing the memory when + * finished. Returns zero on success, negative values on failure. + * + */ +int mls_export_cat(const struct context *context, + unsigned char **low, + size_t *low_len, + unsigned char **high, + size_t *high_len) +{ + int rc = -EPERM; + + if (!selinux_mls_enabled) + return 0; + + if (low != NULL) { + rc = ebitmap_export(&context->range.level[0].cat, + low, + low_len); + if (rc != 0) + goto export_cat_failure; + } + if (high != NULL) { + rc = ebitmap_export(&context->range.level[1].cat, + high, + high_len); + if (rc != 0) + goto export_cat_failure; + } + + return 0; + +export_cat_failure: + if (low != NULL) + kfree(*low); + if (high != NULL) + kfree(*high); + return rc; +} + +/** + * mls_import_cat - Import the MLS categories + * @context: the security context + * @low: the low category + * @low_len: length of the cat_low bitmap in bytes + * @high: the high category + * @high_len: length of the cat_high bitmap in bytes + * + * Description: + * Given the security context and the two category bitmap strings import the + * categories into the security context. The MLS categories are only imported + * if the pointers are not NULL, if they are NULL they are skipped. Returns + * zero on success, negative values on failure. + * + */ +int mls_import_cat(struct context *context, + const unsigned char *low, + size_t low_len, + const unsigned char *high, + size_t high_len) +{ + int rc = -EPERM; + + if (!selinux_mls_enabled) + return 0; + + if (low != NULL) { + rc = ebitmap_import(low, + low_len, + &context->range.level[0].cat); + if (rc != 0) + goto import_cat_failure; + } + if (high != NULL) { + if (high == low) + rc = ebitmap_cpy(&context->range.level[1].cat, + &context->range.level[0].cat); + else + rc = ebitmap_import(high, + high_len, + &context->range.level[1].cat); + if (rc != 0) + goto import_cat_failure; + } + + return 0; + +import_cat_failure: + ebitmap_destroy(&context->range.level[0].cat); + ebitmap_destroy(&context->range.level[1].cat); + return rc; +} diff --git a/security/selinux/ss/mls.h b/security/selinux/ss/mls.h index fbb42f07dd7..df6032c6d49 100644 --- a/security/selinux/ss/mls.h +++ b/security/selinux/ss/mls.h @@ -10,6 +10,13 @@ * * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc. */ +/* + * Updated: Hewlett-Packard <paul.moore@hp.com> + * + * Added support to import/export the MLS label + * + * (c) Copyright Hewlett-Packard Development Company, L.P., 2006 + */ #ifndef _SS_MLS_H_ #define _SS_MLS_H_ @@ -17,6 +24,26 @@ #include "context.h" #include "policydb.h" +/* + * Copies the MLS range from `src' into `dst'. + */ +static inline int mls_copy_context(struct context *dst, + struct context *src) +{ + int l, rc = 0; + + /* Copy the MLS range from the source context */ + for (l = 0; l < 2; l++) { + dst->range.level[l].sens = src->range.level[l].sens; + rc = ebitmap_cpy(&dst->range.level[l].cat, + &src->range.level[l].cat); + if (rc) + break; + } + + return rc; +} + int mls_compute_context_len(struct context *context); void mls_sid_to_context(struct context *context, char **scontext); int mls_context_isvalid(struct policydb *p, struct context *c); @@ -42,5 +69,19 @@ int mls_compute_sid(struct context *scontext, int mls_setup_user_range(struct context *fromcon, struct user_datum *user, struct context *usercon); +void mls_export_lvl(const struct context *context, u32 *low, u32 *high); +void mls_import_lvl(struct context *context, u32 low, u32 high); + +int mls_export_cat(const struct context *context, + unsigned char **low, + size_t *low_len, + unsigned char **high, + size_t *high_len); +int mls_import_cat(struct context *context, + const unsigned char *low, + size_t low_len, + const unsigned char *high, + size_t high_len); + #endif /* _SS_MLS_H */ diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index 85e42988439..7eb69a602d8 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -13,6 +13,11 @@ * * Added conditional policy language extensions * + * Updated: Hewlett-Packard <paul.moore@hp.com> + * + * Added support for NetLabel + * + * Copyright (C) 2006 Hewlett-Packard Development Company, L.P. * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc. * Copyright (C) 2003 - 2004 Tresys Technology, LLC * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com> @@ -29,6 +34,8 @@ #include <linux/sched.h> #include <linux/audit.h> #include <linux/mutex.h> +#include <net/sock.h> +#include <net/netlabel.h> #include "flask.h" #include "avc.h" @@ -40,6 +47,8 @@ #include "services.h" #include "conditional.h" #include "mls.h" +#include "objsec.h" +#include "selinux_netlabel.h" extern void selnl_notify_policyload(u32 seqno); unsigned int policydb_loaded_version; @@ -1241,6 +1250,7 @@ int security_load_policy(void *data, size_t len) selinux_complete_init(); avc_ss_reset(seqno); selnl_notify_policyload(seqno); + selinux_netlbl_cache_invalidate(); return 0; } @@ -1295,6 +1305,7 @@ int security_load_policy(void *data, size_t len) avc_ss_reset(seqno); selnl_notify_policyload(seqno); + selinux_netlbl_cache_invalidate(); return 0; @@ -1817,6 +1828,75 @@ out: return rc; } +/* + * security_sid_mls_copy() - computes a new sid based on the given + * sid and the mls portion of mls_sid. + */ +int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid) +{ + struct context *context1; + struct context *context2; + struct context newcon; + char *s; + u32 len; + int rc = 0; + + if (!ss_initialized || !selinux_mls_enabled) { + *new_sid = sid; + goto out; + } + + context_init(&newcon); + + POLICY_RDLOCK; + context1 = sidtab_search(&sidtab, sid); + if (!context1) { + printk(KERN_ERR "security_sid_mls_copy: unrecognized SID " + "%d\n", sid); + rc = -EINVAL; + goto out_unlock; + } + + context2 = sidtab_search(&sidtab, mls_sid); + if (!context2) { + printk(KERN_ERR "security_sid_mls_copy: unrecognized SID " + "%d\n", mls_sid); + rc = -EINVAL; + goto out_unlock; + } + + newcon.user = context1->user; + newcon.role = context1->role; + newcon.type = context1->type; + rc = mls_copy_context(&newcon, context2); + if (rc) + goto out_unlock; + + + /* Check the validity of the new context. */ + if (!policydb_context_isvalid(&policydb, &newcon)) { + rc = convert_context_handle_invalid_context(&newcon); + if (rc) + goto bad; + } + + rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid); + goto out_unlock; + +bad: + if (!context_struct_to_string(&newcon, &s, &len)) { + audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR, + "security_sid_mls_copy: invalid context %s", s); + kfree(s); + } + +out_unlock: + POLICY_RDUNLOCK; + context_destroy(&newcon); +out: + return rc; +} + struct selinux_audit_rule { u32 au_seqno; struct context au_ctxt; @@ -2064,3 +2144,536 @@ void selinux_audit_set_callback(int (*callback)(void)) { aurule_callback = callback; } + +#ifdef CONFIG_NETLABEL +/* + * This is the structure we store inside the NetLabel cache block. + */ +#define NETLBL_CACHE(x) ((struct netlbl_cache *)(x)) +#define NETLBL_CACHE_T_NONE 0 +#define NETLBL_CACHE_T_SID 1 +#define NETLBL_CACHE_T_MLS 2 +struct netlbl_cache { + u32 type; + union { + u32 sid; + struct mls_range mls_label; + } data; +}; + +/** + * selinux_netlbl_cache_free - Free the NetLabel cached data + * @data: the data to free + * + * Description: + * This function is intended to be used as the free() callback inside the + * netlbl_lsm_cache structure. + * + */ +static void selinux_netlbl_cache_free(const void *data) +{ + struct netlbl_cache *cache = NETLBL_CACHE(data); + switch (cache->type) { + case NETLBL_CACHE_T_MLS: + ebitmap_destroy(&cache->data.mls_label.level[0].cat); + break; + } + kfree(data); +} + +/** + * selinux_netlbl_cache_add - Add an entry to the NetLabel cache + * @skb: the packet + * @ctx: the SELinux context + * + * Description: + * Attempt to cache the context in @ctx, which was derived from the packet in + * @skb, in the NetLabel subsystem cache. + * + */ +static void selinux_netlbl_cache_add(struct sk_buff *skb, struct context *ctx) +{ + struct netlbl_cache *cache = NULL; + struct netlbl_lsm_secattr secattr; + + netlbl_secattr_init(&secattr); + + cache = kzalloc(sizeof(*cache), GFP_ATOMIC); + if (cache == NULL) + goto netlbl_cache_add_failure; + secattr.cache.free = selinux_netlbl_cache_free; + secattr.cache.data = (void *)cache; + + cache->type = NETLBL_CACHE_T_MLS; + if (ebitmap_cpy(&cache->data.mls_label.level[0].cat, + &ctx->range.level[0].cat) != 0) + goto netlbl_cache_add_failure; + cache->data.mls_label.level[1].cat.highbit = + cache->data.mls_label.level[0].cat.highbit; + cache->data.mls_label.level[1].cat.node = + cache->data.mls_label.level[0].cat.node; + cache->data.mls_label.level[0].sens = ctx->range.level[0].sens; + cache->data.mls_label.level[1].sens = ctx->range.level[0].sens; + + if (netlbl_cache_add(skb, &secattr) != 0) + goto netlbl_cache_add_failure; + + return; + +netlbl_cache_add_failure: + netlbl_secattr_destroy(&secattr, 1); +} + +/** + * selinux_netlbl_cache_invalidate - Invalidate the NetLabel cache + * + * Description: + * Invalidate the NetLabel security attribute mapping cache. + * + */ +void selinux_netlbl_cache_invalidate(void) +{ + netlbl_cache_invalidate(); +} + +/** + * selinux_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID + * @skb: the network packet + * @secattr: the NetLabel packet security attributes + * @base_sid: the SELinux SID to use as a context for MLS only attributes + * @sid: the SELinux SID + * + * Description: + * Convert the given NetLabel packet security attributes in @secattr into a + * SELinux SID. If the @secattr field does not contain a full SELinux + * SID/context then use the context in @base_sid as the foundation. If @skb + * is not NULL attempt to cache as much data as possibile. Returns zero on + * success, negative values on failure. + * + */ +static int selinux_netlbl_secattr_to_sid(struct sk_buff *skb, + struct netlbl_lsm_secattr *secattr, + u32 base_sid, + u32 *sid) +{ + int rc = -EIDRM; + struct context *ctx; + struct context ctx_new; + struct netlbl_cache *cache; + + POLICY_RDLOCK; + + if (secattr->cache.data) { + cache = NETLBL_CACHE(secattr->cache.data); + switch (cache->type) { + case NETLBL_CACHE_T_SID: + *sid = cache->data.sid; + rc = 0; + break; + case NETLBL_CACHE_T_MLS: + ctx = sidtab_search(&sidtab, base_sid); + if (ctx == NULL) + goto netlbl_secattr_to_sid_return; + + ctx_new.user = ctx->user; + ctx_new.role = ctx->role; + ctx_new.type = ctx->type; + ctx_new.range.level[0].sens = + cache->data.mls_label.level[0].sens; + ctx_new.range.level[0].cat.highbit = + cache->data.mls_label.level[0].cat.highbit; + ctx_new.range.level[0].cat.node = + cache->data.mls_label.level[0].cat.node; + ctx_new.range.level[1].sens = + cache->data.mls_label.level[1].sens; + ctx_new.range.level[1].cat.highbit = + cache->data.mls_label.level[1].cat.highbit; + ctx_new.range.level[1].cat.node = + cache->data.mls_label.level[1].cat.node; + + rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid); + break; + default: + goto netlbl_secattr_to_sid_return; + } + } else if (secattr->mls_lvl_vld) { + ctx = sidtab_search(&sidtab, base_sid); + if (ctx == NULL) + goto netlbl_secattr_to_sid_return; + + ctx_new.user = ctx->user; + ctx_new.role = ctx->role; + ctx_new.type = ctx->type; + mls_import_lvl(&ctx_new, secattr->mls_lvl, secattr->mls_lvl); + if (secattr->mls_cat) { + if (mls_import_cat(&ctx_new, + secattr->mls_cat, + secattr->mls_cat_len, + NULL, + 0) != 0) + goto netlbl_secattr_to_sid_return; + ctx_new.range.level[1].cat.highbit = + ctx_new.range.level[0].cat.highbit; + ctx_new.range.level[1].cat.node = + ctx_new.range.level[0].cat.node; + } else { + ebitmap_init(&ctx_new.range.level[0].cat); + ebitmap_init(&ctx_new.range.level[1].cat); + } + if (mls_context_isvalid(&policydb, &ctx_new) != 1) + goto netlbl_secattr_to_sid_return_cleanup; + + rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid); + if (rc != 0) + goto netlbl_secattr_to_sid_return_cleanup; + + if (skb != NULL) + selinux_netlbl_cache_add(skb, &ctx_new); + ebitmap_destroy(&ctx_new.range.level[0].cat); + } else { + *sid = SECINITSID_UNLABELED; + rc = 0; + } + +netlbl_secattr_to_sid_return: + POLICY_RDUNLOCK; + return rc; +netlbl_secattr_to_sid_return_cleanup: + ebitmap_destroy(&ctx_new.range.level[0].cat); + goto netlbl_secattr_to_sid_return; +} + +/** + * selinux_netlbl_skbuff_getsid - Get the sid of a packet using NetLabel + * @skb: the packet + * @base_sid: the SELinux SID to use as a context for MLS only attributes + * @sid: the SID + * + * Description: + * Call the NetLabel mechanism to get the security attributes of the given + * packet and use those attributes to determine the correct context/SID to + * assign to the packet. Returns zero on success, negative values on failure. + * + */ +static int selinux_netlbl_skbuff_getsid(struct sk_buff *skb, + u32 base_sid, + u32 *sid) +{ + int rc; + struct netlbl_lsm_secattr secattr; + + netlbl_secattr_init(&secattr); + rc = netlbl_skbuff_getattr(skb, &secattr); + if (rc == 0) + rc = selinux_netlbl_secattr_to_sid(skb, + &secattr, + base_sid, + sid); + netlbl_secattr_destroy(&secattr, 0); + + return rc; +} + +/** + * selinux_netlbl_socket_setsid - Label a socket using the NetLabel mechanism + * @sock: the socket to label + * @sid: the SID to use + * + * Description: + * Attempt to label a socket using the NetLabel mechanism using the given + * SID. Returns zero values on success, negative values on failure. + * + */ +static int selinux_netlbl_socket_setsid(struct socket *sock, u32 sid) +{ + int rc = -ENOENT; + struct sk_security_struct *sksec = sock->sk->sk_security; + struct netlbl_lsm_secattr secattr; + struct context *ctx; + + if (!ss_initialized) + return 0; + + POLICY_RDLOCK; + + ctx = sidtab_search(&sidtab, sid); + if (ctx == NULL) + goto netlbl_socket_setsid_return; + + netlbl_secattr_init(&secattr); + secattr.domain = kstrdup(policydb.p_type_val_to_name[ctx->type - 1], + GFP_ATOMIC); + mls_export_lvl(ctx, &secattr.mls_lvl, NULL); + secattr.mls_lvl_vld = 1; + mls_export_cat(ctx, + &secattr.mls_cat, + &secattr.mls_cat_len, + NULL, + NULL); + + rc = netlbl_socket_setattr(sock, &secattr); + if (rc == 0) + sksec->nlbl_state = NLBL_LABELED; + + netlbl_secattr_destroy(&secattr, 0); + +netlbl_socket_setsid_return: + POLICY_RDUNLOCK; + return rc; +} + +/** + * selinux_netlbl_sk_security_init - Setup the NetLabel fields + * @ssec: the sk_security_struct + * @family: the socket family + * + * Description: + * Called when a new sk_security_struct is allocated to initialize the NetLabel + * fields. + * + */ +void selinux_netlbl_sk_security_init(struct sk_security_struct *ssec, + int family) +{ + if (family == PF_INET) + ssec->nlbl_state = NLBL_REQUIRE; + else + ssec->nlbl_state = NLBL_UNSET; +} + +/** + * selinux_netlbl_sk_clone_security - Copy the NetLabel fields + * @ssec: the original sk_security_struct + * @newssec: the cloned sk_security_struct + * + * Description: + * Clone the NetLabel specific sk_security_struct fields from @ssec to + * @newssec. + * + */ +void selinux_netlbl_sk_clone_security(struct sk_security_struct *ssec, + struct sk_security_struct *newssec) +{ + newssec->sclass = ssec->sclass; + if (ssec->nlbl_state != NLBL_UNSET) + newssec->nlbl_state = NLBL_REQUIRE; + else + newssec->nlbl_state = NLBL_UNSET; +} + +/** + * selinux_netlbl_socket_post_create - Label a socket using NetLabel + * @sock: the socket to label + * @sock_family: the socket family + * @sid: the SID to use + * + * Description: + * Attempt to label a socket using the NetLabel mechanism using the given + * SID. Returns zero values on success, negative values on failure. + * + */ +int selinux_netlbl_socket_post_create(struct socket *sock, + int sock_family, + u32 sid) +{ + struct inode_security_struct *isec = SOCK_INODE(sock)->i_security; + struct sk_security_struct *sksec = sock->sk->sk_security; + + sksec->sclass = isec->sclass; + + if (sock_family != PF_INET) + return 0; + + sksec->nlbl_state = NLBL_REQUIRE; + return selinux_netlbl_socket_setsid(sock, sid); +} + +/** + * selinux_netlbl_sock_graft - Netlabel the new socket + * @sk: the new connection + * @sock: the new socket + * + * Description: + * The connection represented by @sk is being grafted onto @sock so set the + * socket's NetLabel to match the SID of @sk. + * + */ +void selinux_netlbl_sock_graft(struct sock *sk, struct socket *sock) +{ + struct inode_security_struct *isec = SOCK_INODE(sock)->i_security; + struct sk_security_struct *sksec = sk->sk_security; + + sksec->sclass = isec->sclass; + + if (sk->sk_family != PF_INET) + return; + + sksec->nlbl_state = NLBL_REQUIRE; + sksec->peer_sid = sksec->sid; + + /* Try to set the NetLabel on the socket to save time later, if we fail + * here we will pick up the pieces in later calls to + * selinux_netlbl_inode_permission(). */ + selinux_netlbl_socket_setsid(sock, sksec->sid); +} + +/** + * selinux_netlbl_inet_conn_request - Handle a new connection request + * @skb: the packet + * @sock_sid: the SID of the parent socket + * + * Description: + * If present, use the security attributes of the packet in @skb and the + * parent sock's SID to arrive at a SID for the new child sock. Returns the + * SID of the connection or SECSID_NULL on failure. + * + */ +u32 selinux_netlbl_inet_conn_request(struct sk_buff *skb, u32 sock_sid) +{ + int rc; + u32 peer_sid; + + rc = selinux_netlbl_skbuff_getsid(skb, sock_sid, &peer_sid); + if (rc != 0) + return SECSID_NULL; + + if (peer_sid == SECINITSID_UNLABELED) + return SECSID_NULL; + + return peer_sid; +} + +/** + * selinux_netlbl_inode_permission - Verify the socket is NetLabel labeled + * @inode: the file descriptor's inode + * @mask: the permission mask + * + * Description: + * Looks at a file's inode and if it is marked as a socket protected by + * NetLabel then verify that the socket has been labeled, if not try to label + * the socket now with the inode's SID. Returns zero on success, negative + * values on failure. + * + */ +int selinux_netlbl_inode_permission(struct inode *inode, int mask) +{ + int rc; + struct inode_security_struct *isec; + struct sk_security_struct *sksec; + struct socket *sock; + + if (!S_ISSOCK(inode->i_mode)) + return 0; + + sock = SOCKET_I(inode); + isec = inode->i_security; + sksec = sock->sk->sk_security; + down(&isec->sem); + if (unlikely(sksec->nlbl_state == NLBL_REQUIRE && + (mask & (MAY_WRITE | MAY_APPEND)))) { + lock_sock(sock->sk); + rc = selinux_netlbl_socket_setsid(sock, sksec->sid); + release_sock(sock->sk); + } else + rc = 0; + up(&isec->sem); + + return rc; +} + +/** + * selinux_netlbl_sock_rcv_skb - Do an inbound access check using NetLabel + * @sksec: the sock's sk_security_struct + * @skb: the packet + * @ad: the audit data + * + * Description: + * Fetch the NetLabel security attributes from @skb and perform an access check + * against the receiving socket. Returns zero on success, negative values on + * error. + * + */ +int selinux_netlbl_sock_rcv_skb(struct sk_security_struct *sksec, + struct sk_buff *skb, + struct avc_audit_data *ad) +{ + int rc; + u32 netlbl_sid; + u32 recv_perm; + + rc = selinux_netlbl_skbuff_getsid(skb, sksec->sid, &netlbl_sid); + if (rc != 0) + return rc; + + if (netlbl_sid == SECINITSID_UNLABELED) + return 0; + + switch (sksec->sclass) { + case SECCLASS_UDP_SOCKET: + recv_perm = UDP_SOCKET__RECV_MSG; + break; + case SECCLASS_TCP_SOCKET: + recv_perm = TCP_SOCKET__RECV_MSG; + break; + default: + recv_perm = RAWIP_SOCKET__RECV_MSG; + } + + rc = avc_has_perm(sksec->sid, + netlbl_sid, + sksec->sclass, + recv_perm, + ad); + if (rc == 0) + return 0; + + netlbl_skbuff_err(skb, rc); + return rc; +} + +/** + * selinux_netlbl_socket_getpeersec_stream - Return the connected peer's SID + * @sock: the socket + * + * Description: + * Examine @sock to find the connected peer's SID. Returns the SID on success + * or SECSID_NULL on error. + * + */ +u32 selinux_netlbl_socket_getpeersec_stream(struct socket *sock) +{ + struct sk_security_struct *sksec = sock->sk->sk_security; + + if (sksec->peer_sid == SECINITSID_UNLABELED) + return SECSID_NULL; + + return sksec->peer_sid; +} + +/** + * selinux_netlbl_socket_getpeersec_dgram - Return the SID of a NetLabel packet + * @skb: the packet + * + * Description: + * Examine @skb to find the SID assigned to it by NetLabel. Returns the SID on + * success, SECSID_NULL on error. + * + */ +u32 selinux_netlbl_socket_getpeersec_dgram(struct sk_buff *skb) +{ + int peer_sid; + struct sock *sk = skb->sk; + struct inode_security_struct *isec; + + if (sk == NULL || sk->sk_socket == NULL) + return SECSID_NULL; + + isec = SOCK_INODE(sk->sk_socket)->i_security; + if (selinux_netlbl_skbuff_getsid(skb, isec->sid, &peer_sid) != 0) + return SECSID_NULL; + if (peer_sid == SECINITSID_UNLABELED) + return SECSID_NULL; + + return peer_sid; +} +#endif /* CONFIG_NETLABEL */ |