From 3583a71183a02c51ca71cd180e9189cfb0411cc1 Mon Sep 17 00:00:00 2001 From: Adrian Bunk Date: Tue, 22 Jul 2008 20:21:23 +0300 Subject: [PATCH 01/16] make selinux_write_opts() static This patch makes the needlessly global selinux_write_opts() static. Signed-off-by: Adrian Bunk Signed-off-by: James Morris --- security/selinux/hooks.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 3ae9bec5a508..0ffd8814af3e 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -957,7 +957,8 @@ out_err: return rc; } -void selinux_write_opts(struct seq_file *m, struct security_mnt_opts *opts) +static void selinux_write_opts(struct seq_file *m, + struct security_mnt_opts *opts) { int i; char *prefix; From df4ea865f09580b1cad621c0426612f598847815 Mon Sep 17 00:00:00 2001 From: Vesa-Matti J Kari Date: Sun, 20 Jul 2008 23:57:01 +0300 Subject: [PATCH 02/16] SELinux: Trivial minor fixes that change C null character style Trivial minor fixes that change C null character style. Signed-off-by: Vesa-Matti Kari Signed-off-by: James Morris --- security/selinux/ss/conditional.c | 2 +- security/selinux/ss/mls.c | 14 +++++++------- security/selinux/ss/policydb.c | 20 ++++++++++---------- 3 files changed, 18 insertions(+), 18 deletions(-) diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c index fb4efe4f4bc8..f8c850a56ed1 100644 --- a/security/selinux/ss/conditional.c +++ b/security/selinux/ss/conditional.c @@ -239,7 +239,7 @@ int cond_read_bool(struct policydb *p, struct hashtab *h, void *fp) rc = next_entry(key, fp, len); if (rc < 0) goto err; - key[len] = 0; + key[len] = '\0'; if (hashtab_insert(h, key, booldatum)) goto err; diff --git a/security/selinux/ss/mls.c b/security/selinux/ss/mls.c index 77d745da48bb..b5407f16c2a4 100644 --- a/security/selinux/ss/mls.c +++ b/security/selinux/ss/mls.c @@ -283,8 +283,8 @@ int mls_context_to_sid(struct policydb *pol, p++; delim = *p; - if (delim != 0) - *p++ = 0; + if (delim != '\0') + *p++ = '\0'; for (l = 0; l < 2; l++) { levdatum = hashtab_search(pol->p_levels.table, scontextp); @@ -302,14 +302,14 @@ int mls_context_to_sid(struct policydb *pol, while (*p && *p != ',' && *p != '-') p++; delim = *p; - if (delim != 0) - *p++ = 0; + if (delim != '\0') + *p++ = '\0'; /* Separate into range if exists */ rngptr = strchr(scontextp, '.'); if (rngptr != NULL) { /* Remove '.' */ - *rngptr++ = 0; + *rngptr++ = '\0'; } catdatum = hashtab_search(pol->p_cats.table, @@ -357,8 +357,8 @@ int mls_context_to_sid(struct policydb *pol, p++; delim = *p; - if (delim != 0) - *p++ = 0; + if (delim != '\0') + *p++ = '\0'; } else break; } diff --git a/security/selinux/ss/policydb.c b/security/selinux/ss/policydb.c index 2391761ae422..26646305dc0e 100644 --- a/security/selinux/ss/policydb.c +++ b/security/selinux/ss/policydb.c @@ -932,7 +932,7 @@ static int perm_read(struct policydb *p, struct hashtab *h, void *fp) rc = next_entry(key, fp, len); if (rc < 0) goto bad; - key[len] = 0; + key[len] = '\0'; rc = hashtab_insert(h, key, perdatum); if (rc) @@ -979,7 +979,7 @@ static int common_read(struct policydb *p, struct hashtab *h, void *fp) rc = next_entry(key, fp, len); if (rc < 0) goto bad; - key[len] = 0; + key[len] = '\0'; for (i = 0; i < nel; i++) { rc = perm_read(p, comdatum->permissions.table, fp); @@ -1117,7 +1117,7 @@ static int class_read(struct policydb *p, struct hashtab *h, void *fp) rc = next_entry(key, fp, len); if (rc < 0) goto bad; - key[len] = 0; + key[len] = '\0'; if (len2) { cladatum->comkey = kmalloc(len2 + 1, GFP_KERNEL); @@ -1128,7 +1128,7 @@ static int class_read(struct policydb *p, struct hashtab *h, void *fp) rc = next_entry(cladatum->comkey, fp, len2); if (rc < 0) goto bad; - cladatum->comkey[len2] = 0; + cladatum->comkey[len2] = '\0'; cladatum->comdatum = hashtab_search(p->p_commons.table, cladatum->comkey); @@ -1201,7 +1201,7 @@ static int role_read(struct policydb *p, struct hashtab *h, void *fp) rc = next_entry(key, fp, len); if (rc < 0) goto bad; - key[len] = 0; + key[len] = '\0'; rc = ebitmap_read(&role->dominates, fp); if (rc) @@ -1262,7 +1262,7 @@ static int type_read(struct policydb *p, struct hashtab *h, void *fp) rc = next_entry(key, fp, len); if (rc < 0) goto bad; - key[len] = 0; + key[len] = '\0'; rc = hashtab_insert(h, key, typdatum); if (rc) @@ -1334,7 +1334,7 @@ static int user_read(struct policydb *p, struct hashtab *h, void *fp) rc = next_entry(key, fp, len); if (rc < 0) goto bad; - key[len] = 0; + key[len] = '\0'; rc = ebitmap_read(&usrdatum->roles, fp); if (rc) @@ -1388,7 +1388,7 @@ static int sens_read(struct policydb *p, struct hashtab *h, void *fp) rc = next_entry(key, fp, len); if (rc < 0) goto bad; - key[len] = 0; + key[len] = '\0'; levdatum->level = kmalloc(sizeof(struct mls_level), GFP_ATOMIC); if (!levdatum->level) { @@ -1440,7 +1440,7 @@ static int cat_read(struct policydb *p, struct hashtab *h, void *fp) rc = next_entry(key, fp, len); if (rc < 0) goto bad; - key[len] = 0; + key[len] = '\0'; rc = hashtab_insert(h, key, catdatum); if (rc) @@ -1523,7 +1523,7 @@ int policydb_read(struct policydb *p, void *fp) kfree(policydb_str); goto bad; } - policydb_str[len] = 0; + policydb_str[len] = '\0'; if (strcmp(policydb_str, POLICYDB_STRING)) { printk(KERN_ERR "SELinux: policydb string %s does not match " "my string %s\n", policydb_str, POLICYDB_STRING); From 0c0e186f812457e527c420f7a4d02865fd0dc7d2 Mon Sep 17 00:00:00 2001 From: Vesa-Matti J Kari Date: Mon, 21 Jul 2008 02:50:20 +0300 Subject: [PATCH 03/16] SELinux: trivial, remove unneeded local variable Hello, Remove unneeded local variable: struct avtab_node *newnode Signed-off-by: Vesa-Matti Kari Signed-off-by: James Morris --- security/selinux/ss/avtab.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/security/selinux/ss/avtab.c b/security/selinux/ss/avtab.c index a1be97f8beea..e8ae812d6af7 100644 --- a/security/selinux/ss/avtab.c +++ b/security/selinux/ss/avtab.c @@ -98,7 +98,7 @@ struct avtab_node * avtab_insert_nonunique(struct avtab *h, struct avtab_key *key, struct avtab_datum *datum) { int hvalue; - struct avtab_node *prev, *cur, *newnode; + struct avtab_node *prev, *cur; u16 specified = key->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD); if (!h || !h->htable) @@ -122,9 +122,7 @@ avtab_insert_nonunique(struct avtab *h, struct avtab_key *key, struct avtab_datu key->target_class < cur->key.target_class) break; } - newnode = avtab_insert_node(h, hvalue, prev, cur, key, datum); - - return newnode; + return avtab_insert_node(h, hvalue, prev, cur, key, datum); } struct avtab_datum *avtab_search(struct avtab *h, struct avtab_key *key) From cf9481e289247fe9cf40f2e2481220d899132049 Mon Sep 17 00:00:00 2001 From: David Howells Date: Sun, 27 Jul 2008 21:31:07 +1000 Subject: [PATCH 04/16] SELinux: Fix a potentially uninitialised variable in SELinux hooks Fix a potentially uninitialised variable in SELinux hooks that's given a pointer to the network address by selinux_parse_skb() passing a pointer back through its argument list. By restructuring selinux_parse_skb(), the compiler can see that the error case need not set it as the caller will return immediately. Signed-off-by: David Howells Signed-off-by: James Morris --- security/selinux/hooks.c | 42 +++++++++++++++++++++++----------------- 1 file changed, 24 insertions(+), 18 deletions(-) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 0ffd8814af3e..3eae30609702 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -3539,38 +3539,44 @@ out: #endif /* IPV6 */ static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad, - char **addrp, int src, u8 *proto) + char **_addrp, int src, u8 *proto) { - int ret = 0; + char *addrp; + int ret; switch (ad->u.net.family) { case PF_INET: ret = selinux_parse_skb_ipv4(skb, ad, proto); - if (ret || !addrp) - break; - *addrp = (char *)(src ? &ad->u.net.v4info.saddr : - &ad->u.net.v4info.daddr); - break; + if (ret) + goto parse_error; + addrp = (char *)(src ? &ad->u.net.v4info.saddr : + &ad->u.net.v4info.daddr); + goto okay; #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) case PF_INET6: ret = selinux_parse_skb_ipv6(skb, ad, proto); - if (ret || !addrp) - break; - *addrp = (char *)(src ? &ad->u.net.v6info.saddr : - &ad->u.net.v6info.daddr); - break; + if (ret) + goto parse_error; + addrp = (char *)(src ? &ad->u.net.v6info.saddr : + &ad->u.net.v6info.daddr); + goto okay; #endif /* IPV6 */ default: - break; + addrp = NULL; + goto okay; } - if (unlikely(ret)) - printk(KERN_WARNING - "SELinux: failure in selinux_parse_skb()," - " unable to parse packet\n"); - +parse_error: + printk(KERN_WARNING + "SELinux: failure in selinux_parse_skb()," + " unable to parse packet\n"); return ret; + +okay: + if (_addrp) + *_addrp = addrp; + return 0; } /** From 15446235367fa4a621ff5abfa4b6ebbe25b33763 Mon Sep 17 00:00:00 2001 From: Casey Schaufler Date: Wed, 30 Jul 2008 15:37:11 -0700 Subject: [PATCH 05/16] smack: limit privilege by label There have been a number of requests to make the Smack LSM enforce MAC even in the face of privilege, either capability based or superuser based. This is not universally desired, however, so it seems desirable to make it optional. Further, at least one legacy OS implemented a scheme whereby only processes running with one particular label could be exempt from MAC. This patch supports these three cases. If /smack/onlycap is empty (unset or null-string) privilege is enforced in the normal way. If /smack/onlycap contains a label only processes running with that label may be MAC exempt. If the label in /smack/onlycap is the star label ("*") the semantics of the star label combine with the privilege restrictions to prevent any violations of MAC, even in the presence of privilege. Again, this will be independent of the privilege scheme. Signed-off-by: Casey Schaufler Reviewed-by: James Morris --- security/smack/smack.h | 1 + security/smack/smack_access.c | 10 +++- security/smack/smackfs.c | 92 +++++++++++++++++++++++++++++++++++ 3 files changed, 102 insertions(+), 1 deletion(-) diff --git a/security/smack/smack.h b/security/smack/smack.h index 4a4477f5afdc..31dce559595a 100644 --- a/security/smack/smack.h +++ b/security/smack/smack.h @@ -178,6 +178,7 @@ u32 smack_to_secid(const char *); extern int smack_cipso_direct; extern int smack_net_nltype; extern char *smack_net_ambient; +extern char *smack_onlycap; extern struct smack_known *smack_known; extern struct smack_known smack_known_floor; diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c index f6b5f6eed6dd..79ff21ed4c3b 100644 --- a/security/smack/smack_access.c +++ b/security/smack/smack_access.c @@ -157,7 +157,7 @@ int smk_access(char *subject_label, char *object_label, int request) * * This function checks the current subject label/object label pair * in the access rule list and returns 0 if the access is permitted, - * non zero otherwise. It allows that current my have the capability + * non zero otherwise. It allows that current may have the capability * to override the rules. */ int smk_curacc(char *obj_label, u32 mode) @@ -168,6 +168,14 @@ int smk_curacc(char *obj_label, u32 mode) if (rc == 0) return 0; + /* + * Return if a specific label has been designated as the + * only one that gets privilege and current does not + * have that label. + */ + if (smack_onlycap != NULL && smack_onlycap != current->security) + return rc; + if (capable(CAP_MAC_OVERRIDE)) return 0; diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c index 271a835fbbe3..e7c642458ec9 100644 --- a/security/smack/smackfs.c +++ b/security/smack/smackfs.c @@ -39,6 +39,7 @@ enum smk_inos { SMK_DIRECT = 6, /* CIPSO level indicating direct label */ SMK_AMBIENT = 7, /* internet ambient label */ SMK_NLTYPE = 8, /* label scheme to use by default */ + SMK_ONLYCAP = 9, /* the only "capable" label */ }; /* @@ -68,6 +69,16 @@ int smack_net_nltype = NETLBL_NLTYPE_CIPSOV4; */ int smack_cipso_direct = SMACK_CIPSO_DIRECT_DEFAULT; +/* + * Unless a process is running with this label even + * having CAP_MAC_OVERRIDE isn't enough to grant + * privilege to violate MAC policy. If no label is + * designated (the NULL case) capabilities apply to + * everyone. It is expected that the hat (^) label + * will be used if any label is used. + */ +char *smack_onlycap; + static int smk_cipso_doi_value = SMACK_CIPSO_DOI_DEFAULT; struct smk_list_entry *smack_list; @@ -787,6 +798,85 @@ static const struct file_operations smk_ambient_ops = { .write = smk_write_ambient, }; +/** + * smk_read_onlycap - read() for /smack/onlycap + * @filp: file pointer, not actually used + * @buf: where to put the result + * @cn: maximum to send along + * @ppos: where to start + * + * Returns number of bytes read or error code, as appropriate + */ +static ssize_t smk_read_onlycap(struct file *filp, char __user *buf, + size_t cn, loff_t *ppos) +{ + char *smack = ""; + ssize_t rc = -EINVAL; + int asize; + + if (*ppos != 0) + return 0; + + if (smack_onlycap != NULL) + smack = smack_onlycap; + + asize = strlen(smack) + 1; + + if (cn >= asize) + rc = simple_read_from_buffer(buf, cn, ppos, smack, asize); + + return rc; +} + +/** + * smk_write_onlycap - write() for /smack/onlycap + * @filp: file pointer, not actually used + * @buf: where to get the data from + * @count: bytes sent + * @ppos: where to start + * + * Returns number of bytes written or error code, as appropriate + */ +static ssize_t smk_write_onlycap(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + char in[SMK_LABELLEN]; + char *sp = current->security; + + if (!capable(CAP_MAC_ADMIN)) + return -EPERM; + + /* + * This can be done using smk_access() but is done + * explicitly for clarity. The smk_access() implementation + * would use smk_access(smack_onlycap, MAY_WRITE) + */ + if (smack_onlycap != NULL && smack_onlycap != sp) + return -EPERM; + + if (count >= SMK_LABELLEN) + return -EINVAL; + + if (copy_from_user(in, buf, count) != 0) + return -EFAULT; + + /* + * Should the null string be passed in unset the onlycap value. + * This seems like something to be careful with as usually + * smk_import only expects to return NULL for errors. It + * is usually the case that a nullstring or "\n" would be + * bad to pass to smk_import but in fact this is useful here. + */ + smack_onlycap = smk_import(in, count); + + return count; +} + +static const struct file_operations smk_onlycap_ops = { + .read = smk_read_onlycap, + .write = smk_write_onlycap, +}; + struct option_names { int o_number; char *o_name; @@ -919,6 +1009,8 @@ static int smk_fill_super(struct super_block *sb, void *data, int silent) {"ambient", &smk_ambient_ops, S_IRUGO|S_IWUSR}, [SMK_NLTYPE] = {"nltype", &smk_nltype_ops, S_IRUGO|S_IWUSR}, + [SMK_ONLYCAP] = + {"onlycap", &smk_onlycap_ops, S_IRUGO|S_IWUSR}, /* last one */ {""} }; From 421fae06be9e0dac45747494756b3580643815f9 Mon Sep 17 00:00:00 2001 From: Vesa-Matti Kari Date: Wed, 6 Aug 2008 18:24:51 +0300 Subject: [PATCH 06/16] selinux: conditional expression type validation was off-by-one expr_isvalid() in conditional.c was off-by-one and allowed invalid expression type COND_LAST. However, it is this header file that needs to be fixed. That way the if-statement's disjunction's second component reads more naturally, "if expr type is greater than the last allowed value" ( rather than using ">=" in conditional.c): if (expr->expr_type <= 0 || expr->expr_type > COND_LAST) Signed-off-by: Vesa-Matti Kari Signed-off-by: James Morris --- security/selinux/ss/conditional.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/security/selinux/ss/conditional.h b/security/selinux/ss/conditional.h index 65b9f8366e9c..53ddb013ae57 100644 --- a/security/selinux/ss/conditional.h +++ b/security/selinux/ss/conditional.h @@ -28,7 +28,7 @@ struct cond_expr { #define COND_XOR 5 /* bool ^ bool */ #define COND_EQ 6 /* bool == bool */ #define COND_NEQ 7 /* bool != bool */ -#define COND_LAST 8 +#define COND_LAST COND_NEQ __u32 expr_type; __u32 bool; struct cond_expr *next; From dbc74c65b3fd841985935f676388c82d6b85c485 Mon Sep 17 00:00:00 2001 From: Vesa-Matti Kari Date: Thu, 7 Aug 2008 03:18:20 +0300 Subject: [PATCH 07/16] selinux: Unify for- and while-loop style Replace "thing != NULL" comparisons with just "thing" to make the code look more uniform (mixed styles were used even in the same source file). Signed-off-by: Vesa-Matti Kari Acked-by: Stephen Smalley Signed-off-by: James Morris --- security/selinux/ss/avtab.c | 2 +- security/selinux/ss/conditional.c | 16 ++++++++-------- security/selinux/ss/ebitmap.c | 4 ++-- security/selinux/ss/hashtab.c | 6 +++--- security/selinux/ss/services.c | 8 ++++---- security/selinux/ss/sidtab.c | 12 ++++++------ 6 files changed, 24 insertions(+), 24 deletions(-) diff --git a/security/selinux/ss/avtab.c b/security/selinux/ss/avtab.c index e8ae812d6af7..1215b8e47dba 100644 --- a/security/selinux/ss/avtab.c +++ b/security/selinux/ss/avtab.c @@ -229,7 +229,7 @@ void avtab_destroy(struct avtab *h) for (i = 0; i < h->nslot; i++) { cur = h->htable[i]; - while (cur != NULL) { + while (cur) { temp = cur; cur = cur->next; kmem_cache_free(avtab_node_cachep, temp); diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c index f8c850a56ed1..4a4e35cac22b 100644 --- a/security/selinux/ss/conditional.c +++ b/security/selinux/ss/conditional.c @@ -29,7 +29,7 @@ static int cond_evaluate_expr(struct policydb *p, struct cond_expr *expr) int s[COND_EXPR_MAXDEPTH]; int sp = -1; - for (cur = expr; cur != NULL; cur = cur->next) { + for (cur = expr; cur; cur = cur->next) { switch (cur->expr_type) { case COND_BOOL: if (sp == (COND_EXPR_MAXDEPTH - 1)) @@ -97,14 +97,14 @@ int evaluate_cond_node(struct policydb *p, struct cond_node *node) if (new_state == -1) printk(KERN_ERR "SELinux: expression result was undefined - disabling all rules.\n"); /* turn the rules on or off */ - for (cur = node->true_list; cur != NULL; cur = cur->next) { + for (cur = node->true_list; cur; cur = cur->next) { if (new_state <= 0) cur->node->key.specified &= ~AVTAB_ENABLED; else cur->node->key.specified |= AVTAB_ENABLED; } - for (cur = node->false_list; cur != NULL; cur = cur->next) { + for (cur = node->false_list; cur; cur = cur->next) { /* -1 or 1 */ if (new_state) cur->node->key.specified &= ~AVTAB_ENABLED; @@ -128,7 +128,7 @@ int cond_policydb_init(struct policydb *p) static void cond_av_list_destroy(struct cond_av_list *list) { struct cond_av_list *cur, *next; - for (cur = list; cur != NULL; cur = next) { + for (cur = list; cur; cur = next) { next = cur->next; /* the avtab_ptr_t node is destroy by the avtab */ kfree(cur); @@ -139,7 +139,7 @@ static void cond_node_destroy(struct cond_node *node) { struct cond_expr *cur_expr, *next_expr; - for (cur_expr = node->expr; cur_expr != NULL; cur_expr = next_expr) { + for (cur_expr = node->expr; cur_expr; cur_expr = next_expr) { next_expr = cur_expr->next; kfree(cur_expr); } @@ -155,7 +155,7 @@ static void cond_list_destroy(struct cond_node *list) if (list == NULL) return; - for (cur = list; cur != NULL; cur = next) { + for (cur = list; cur; cur = next) { next = cur->next; cond_node_destroy(cur); } @@ -291,7 +291,7 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum goto err; } found = 0; - for (cur = other; cur != NULL; cur = cur->next) { + for (cur = other; cur; cur = cur->next) { if (cur->node == node_ptr) { found = 1; break; @@ -485,7 +485,7 @@ void cond_compute_av(struct avtab *ctab, struct avtab_key *key, struct av_decisi if (!ctab || !key || !avd) return; - for (node = avtab_search_node(ctab, key); node != NULL; + for (node = avtab_search_node(ctab, key); node; node = avtab_search_node_next(node, key->specified)) { if ((u16)(AVTAB_ALLOWED|AVTAB_ENABLED) == (node->key.specified & (AVTAB_ALLOWED|AVTAB_ENABLED))) diff --git a/security/selinux/ss/ebitmap.c b/security/selinux/ss/ebitmap.c index ddc275490af8..68c7348d1acc 100644 --- a/security/selinux/ss/ebitmap.c +++ b/security/selinux/ss/ebitmap.c @@ -109,7 +109,7 @@ int ebitmap_netlbl_export(struct ebitmap *ebmap, *catmap = c_iter; c_iter->startbit = e_iter->startbit & ~(NETLBL_CATMAP_SIZE - 1); - while (e_iter != NULL) { + while (e_iter) { for (i = 0; i < EBITMAP_UNIT_NUMS; i++) { unsigned int delta, e_startbit, c_endbit; @@ -197,7 +197,7 @@ int ebitmap_netlbl_import(struct ebitmap *ebmap, } } c_iter = c_iter->next; - } while (c_iter != NULL); + } while (c_iter); if (e_iter != NULL) ebmap->highbit = e_iter->startbit + EBITMAP_SIZE; else diff --git a/security/selinux/ss/hashtab.c b/security/selinux/ss/hashtab.c index 2e7788e13213..933e735bb185 100644 --- a/security/selinux/ss/hashtab.c +++ b/security/selinux/ss/hashtab.c @@ -81,7 +81,7 @@ void *hashtab_search(struct hashtab *h, const void *key) hvalue = h->hash_value(h, key); cur = h->htable[hvalue]; - while (cur != NULL && h->keycmp(h, key, cur->key) > 0) + while (cur && h->keycmp(h, key, cur->key) > 0) cur = cur->next; if (cur == NULL || (h->keycmp(h, key, cur->key) != 0)) @@ -100,7 +100,7 @@ void hashtab_destroy(struct hashtab *h) for (i = 0; i < h->size; i++) { cur = h->htable[i]; - while (cur != NULL) { + while (cur) { temp = cur; cur = cur->next; kfree(temp); @@ -127,7 +127,7 @@ int hashtab_map(struct hashtab *h, for (i = 0; i < h->size; i++) { cur = h->htable[i]; - while (cur != NULL) { + while (cur) { ret = apply(cur->key, cur->datum, args); if (ret) return ret; diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index b52f923ce680..5a0536bddc63 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -356,7 +356,7 @@ static int context_struct_compute_av(struct context *scontext, avkey.source_type = i + 1; avkey.target_type = j + 1; for (node = avtab_search_node(&policydb.te_avtab, &avkey); - node != NULL; + node; node = avtab_search_node_next(node, avkey.specified)) { if (node->key.specified == AVTAB_ALLOWED) avd->allowed |= node->datum.data; @@ -1037,7 +1037,7 @@ static int security_compute_sid(u32 ssid, /* If no permanent rule, also check for enabled conditional rules */ if (!avdatum) { node = avtab_search_node(&policydb.te_cond_avtab, &avkey); - for (; node != NULL; node = avtab_search_node_next(node, specified)) { + for (; node; node = avtab_search_node_next(node, specified)) { if (node->key.specified & AVTAB_ENABLED) { avdatum = &node->datum; break; @@ -2050,7 +2050,7 @@ int security_set_bools(int len, int *values) policydb.bool_val_to_struct[i]->state = 0; } - for (cur = policydb.cond_list; cur != NULL; cur = cur->next) { + for (cur = policydb.cond_list; cur; cur = cur->next) { rc = evaluate_cond_node(&policydb, cur); if (rc) goto out; @@ -2102,7 +2102,7 @@ static int security_preserve_bools(struct policydb *p) if (booldatum) booldatum->state = bvalues[i]; } - for (cur = p->cond_list; cur != NULL; cur = cur->next) { + for (cur = p->cond_list; cur; cur = cur->next) { rc = evaluate_cond_node(p, cur); if (rc) goto out; diff --git a/security/selinux/ss/sidtab.c b/security/selinux/ss/sidtab.c index a81ded104129..e817989764cd 100644 --- a/security/selinux/ss/sidtab.c +++ b/security/selinux/ss/sidtab.c @@ -43,7 +43,7 @@ int sidtab_insert(struct sidtab *s, u32 sid, struct context *context) hvalue = SIDTAB_HASH(sid); prev = NULL; cur = s->htable[hvalue]; - while (cur != NULL && sid > cur->sid) { + while (cur && sid > cur->sid) { prev = cur; cur = cur->next; } @@ -92,7 +92,7 @@ static struct context *sidtab_search_core(struct sidtab *s, u32 sid, int force) hvalue = SIDTAB_HASH(sid); cur = s->htable[hvalue]; - while (cur != NULL && sid > cur->sid) + while (cur && sid > cur->sid) cur = cur->next; if (force && cur && sid == cur->sid && cur->context.len) @@ -103,7 +103,7 @@ static struct context *sidtab_search_core(struct sidtab *s, u32 sid, int force) sid = SECINITSID_UNLABELED; hvalue = SIDTAB_HASH(sid); cur = s->htable[hvalue]; - while (cur != NULL && sid > cur->sid) + while (cur && sid > cur->sid) cur = cur->next; if (!cur || sid != cur->sid) return NULL; @@ -136,7 +136,7 @@ int sidtab_map(struct sidtab *s, for (i = 0; i < SIDTAB_SIZE; i++) { cur = s->htable[i]; - while (cur != NULL) { + while (cur) { rc = apply(cur->sid, &cur->context, args); if (rc) goto out; @@ -155,7 +155,7 @@ static inline u32 sidtab_search_context(struct sidtab *s, for (i = 0; i < SIDTAB_SIZE; i++) { cur = s->htable[i]; - while (cur != NULL) { + while (cur) { if (context_cmp(&cur->context, context)) return cur->sid; cur = cur->next; @@ -242,7 +242,7 @@ void sidtab_destroy(struct sidtab *s) for (i = 0; i < SIDTAB_SIZE; i++) { cur = s->htable[i]; - while (cur != NULL) { + while (cur) { temp = cur; cur = cur->next; context_destroy(&temp->context); From 3f23d815c5049c9d7022226cec2242e384dd0b43 Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Sun, 17 Aug 2008 21:44:22 -0700 Subject: [PATCH 08/16] security: add/fix security kernel-doc Add security/inode.c functions to the kernel-api docbook. Use '%' on constants in kernel-doc notation. Fix several typos/spellos in security function descriptions. Signed-off-by: Randy Dunlap Signed-off-by: James Morris --- Documentation/DocBook/kernel-api.tmpl | 1 + security/inode.c | 33 +++++++++++++-------------- security/security.c | 8 +++---- 3 files changed, 21 insertions(+), 21 deletions(-) diff --git a/Documentation/DocBook/kernel-api.tmpl b/Documentation/DocBook/kernel-api.tmpl index b7b1482f6e04..cd0e6d5370d7 100644 --- a/Documentation/DocBook/kernel-api.tmpl +++ b/Documentation/DocBook/kernel-api.tmpl @@ -283,6 +283,7 @@ X!Earch/x86/kernel/mca_32.c Security Framework !Isecurity/security.c +!Esecurity/inode.c diff --git a/security/inode.c b/security/inode.c index acc6cf0d7900..ca4958ebad8d 100644 --- a/security/inode.c +++ b/security/inode.c @@ -190,7 +190,7 @@ static int create_by_name(const char *name, mode_t mode, * @name: a pointer to a string containing the name of the file to create. * @mode: the permission that the file should have * @parent: a pointer to the parent dentry for this file. This should be a - * directory dentry if set. If this paramater is NULL, then the + * directory dentry if set. If this parameter is %NULL, then the * file will be created in the root of the securityfs filesystem. * @data: a pointer to something that the caller will want to get to later * on. The inode.i_private pointer will point to this value on @@ -199,18 +199,18 @@ static int create_by_name(const char *name, mode_t mode, * this file. * * This is the basic "create a file" function for securityfs. It allows for a - * wide range of flexibility in createing a file, or a directory (if you + * wide range of flexibility in creating a file, or a directory (if you * want to create a directory, the securityfs_create_dir() function is - * recommended to be used instead.) + * recommended to be used instead). * - * This function will return a pointer to a dentry if it succeeds. This + * This function returns a pointer to a dentry if it succeeds. This * pointer must be passed to the securityfs_remove() function when the file is * to be removed (no automatic cleanup happens if your module is unloaded, - * you are responsible here.) If an error occurs, NULL will be returned. + * you are responsible here). If an error occurs, %NULL is returned. * - * If securityfs is not enabled in the kernel, the value -ENODEV will be + * If securityfs is not enabled in the kernel, the value %-ENODEV is * returned. It is not wise to check for this value, but rather, check for - * NULL or !NULL instead as to eliminate the need for #ifdef in the calling + * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling * code. */ struct dentry *securityfs_create_file(const char *name, mode_t mode, @@ -252,19 +252,19 @@ EXPORT_SYMBOL_GPL(securityfs_create_file); * @name: a pointer to a string containing the name of the directory to * create. * @parent: a pointer to the parent dentry for this file. This should be a - * directory dentry if set. If this paramater is NULL, then the + * directory dentry if set. If this parameter is %NULL, then the * directory will be created in the root of the securityfs filesystem. * - * This function creates a directory in securityfs with the given name. + * This function creates a directory in securityfs with the given @name. * - * This function will return a pointer to a dentry if it succeeds. This + * This function returns a pointer to a dentry if it succeeds. This * pointer must be passed to the securityfs_remove() function when the file is * to be removed (no automatic cleanup happens if your module is unloaded, - * you are responsible here.) If an error occurs, NULL will be returned. + * you are responsible here). If an error occurs, %NULL will be returned. * - * If securityfs is not enabled in the kernel, the value -ENODEV will be + * If securityfs is not enabled in the kernel, the value %-ENODEV is * returned. It is not wise to check for this value, but rather, check for - * NULL or !NULL instead as to eliminate the need for #ifdef in the calling + * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling * code. */ struct dentry *securityfs_create_dir(const char *name, struct dentry *parent) @@ -278,16 +278,15 @@ EXPORT_SYMBOL_GPL(securityfs_create_dir); /** * securityfs_remove - removes a file or directory from the securityfs filesystem * - * @dentry: a pointer to a the dentry of the file or directory to be - * removed. + * @dentry: a pointer to a the dentry of the file or directory to be removed. * * This function removes a file or directory in securityfs that was previously * created with a call to another securityfs function (like * securityfs_create_file() or variants thereof.) * * This function is required to be called in order for the file to be - * removed, no automatic cleanup of files will happen when a module is - * removed, you are responsible here. + * removed. No automatic cleanup of files will happen when a module is + * removed; you are responsible here. */ void securityfs_remove(struct dentry *dentry) { diff --git a/security/security.c b/security/security.c index ff7068727757..d953d251fdca 100644 --- a/security/security.c +++ b/security/security.c @@ -82,8 +82,8 @@ __setup("security=", choose_lsm); * * Return true if: * -The passed LSM is the one chosen by user at boot time, - * -or user didsn't specify a specific LSM and we're the first to ask - * for registeration permissoin, + * -or user didn't specify a specific LSM and we're the first to ask + * for registration permission, * -or the passed LSM is currently loaded. * Otherwise, return false. */ @@ -101,13 +101,13 @@ int __init security_module_enable(struct security_operations *ops) * register_security - registers a security framework with the kernel * @ops: a pointer to the struct security_options that is to be registered * - * This function is to allow a security module to register itself with the + * This function allows a security module to register itself with the * kernel security subsystem. Some rudimentary checking is done on the @ops * value passed to this function. You'll need to check first if your LSM * is allowed to register its @ops by calling security_module_enable(@ops). * * If there is already a security module registered with the kernel, - * an error will be returned. Otherwise 0 is returned on success. + * an error will be returned. Otherwise %0 is returned on success. */ int register_security(struct security_operations *ops) { From 93c06cbbf9fea5d5be1778febb7fa9ab1a74e5f5 Mon Sep 17 00:00:00 2001 From: "Serge E. Hallyn" Date: Tue, 26 Aug 2008 14:47:57 -0500 Subject: [PATCH 09/16] selinux: add support for installing a dummy policy (v2) In August 2006 I posted a patch generating a minimal SELinux policy. This week, David P. Quigley posted an updated version of that as a patch against the kernel. It also had nice logic for auto-installing the policy. Following is David's original patch intro (preserved especially bc it has stats on the generated policies): se interested in the changes there were only two significant changes. The first is that the iteration through the list of classes used NULL as a sentinel value. The problem with this is that the class_to_string array actually has NULL entries in its table as place holders for the user space object classes. The second change was that it would seem at some point the initial sids table was NULL terminated. This is no longer the case so that iteration has to be done on array length instead of looking for NULL. Some statistics on the policy that it generates: The policy consists of 523 lines which contain no blank lines. Of those 523 lines 453 of them are class, permission, and initial sid definitions. These lines are usually little to no concern to the policy developer since they will not be adding object classes or permissions. Of the remaining 70 lines there is one type, one role, and one user statement. The remaining lines are broken into three portions. The first group are TE allow rules which make up 29 of the remaining lines, the second is assignment of labels to the initial sids which consist of 27 lines, and file system labeling statements which are the remaining 11. In addition to the policy.conf generated there is a single file_contexts file containing two lines which labels the entire system with base_t. This policy generates a policy.23 binary that is 7920 bytes. (then a few versions later...): The new policy is 587 lines (stripped of blank lines) with 476 of those lines being the boilerplate that I mentioned last time. The remaining 111 lines have the 3 lines for type, user, and role, 70 lines for the allow rules (one for each object class including user space object classes), 27 lines to assign types to the initial sids, and 11 lines for file system labeling. The policy binary is 9194 bytes. Changelog: Aug 26: Added Documentation/SELinux.txt Aug 26: Incorporated a set of comments by Stephen Smalley: 1. auto-setup SELINUXTYPE=dummy 2. don't auto-install if selinux is enabled with non-dummy policy 3. don't re-compute policy version 4. /sbin/setfiles not /usr/sbin/setfiles Aug 22: As per JMorris comments, made sure make distclean cleans up the mdp directory. Removed a check for file_contexts which is now created in the same file as the check, making it superfluous. Signed-off-by: Serge Hallyn Signed-off-by: David Quigley Signed-off-by: James Morris --- Documentation/SELinux.txt | 27 ++++ scripts/Makefile | 3 +- scripts/selinux/Makefile | 2 + scripts/selinux/README | 2 + scripts/selinux/install_policy.sh | 69 +++++++++ scripts/selinux/mdp/Makefile | 5 + scripts/selinux/mdp/dbus_contexts | 6 + scripts/selinux/mdp/mdp.c | 242 ++++++++++++++++++++++++++++++ 8 files changed, 355 insertions(+), 1 deletion(-) create mode 100644 Documentation/SELinux.txt create mode 100644 scripts/selinux/Makefile create mode 100644 scripts/selinux/README create mode 100644 scripts/selinux/install_policy.sh create mode 100644 scripts/selinux/mdp/Makefile create mode 100644 scripts/selinux/mdp/dbus_contexts create mode 100644 scripts/selinux/mdp/mdp.c diff --git a/Documentation/SELinux.txt b/Documentation/SELinux.txt new file mode 100644 index 000000000000..07eae00f3314 --- /dev/null +++ b/Documentation/SELinux.txt @@ -0,0 +1,27 @@ +If you want to use SELinux, chances are you will want +to use the distro-provided policies, or install the +latest reference policy release from + http://oss.tresys.com/projects/refpolicy + +However, if you want to install a dummy policy for +testing, you can do using 'mdp' provided under +scripts/selinux. Note that this requires the selinux +userspace to be installed - in particular you will +need checkpolicy to compile a kernel, and setfiles and +fixfiles to label the filesystem. + + 1. Compile the kernel with selinux enabled. + 2. Type 'make' to compile mdp. + 3. Make sure that you are not running with + SELinux enabled and a real policy. If + you are, reboot with selinux disabled + before continuing. + 4. Run install_policy.sh: + cd scripts/selinux + sh install_policy.sh + +Step 4 will create a new dummy policy valid for your +kernel, with a single selinux user, role, and type. +It will compile the policy, will set your SELINUXTYPE to +dummy in /etc/selinux/config, install the compiled policy +as 'dummy', and relabel your filesystem. diff --git a/scripts/Makefile b/scripts/Makefile index 1c73c5aea66b..aafdf064feef 100644 --- a/scripts/Makefile +++ b/scripts/Makefile @@ -20,6 +20,7 @@ hostprogs-y += unifdef subdir-$(CONFIG_MODVERSIONS) += genksyms subdir-y += mod +subdir-$(CONFIG_SECURITY_SELINUX) += selinux # Let clean descend into subdirs -subdir- += basic kconfig package +subdir- += basic kconfig package selinux diff --git a/scripts/selinux/Makefile b/scripts/selinux/Makefile new file mode 100644 index 000000000000..ca4b1ec01822 --- /dev/null +++ b/scripts/selinux/Makefile @@ -0,0 +1,2 @@ +subdir-y := mdp +subdir- += mdp diff --git a/scripts/selinux/README b/scripts/selinux/README new file mode 100644 index 000000000000..a936315ba2c8 --- /dev/null +++ b/scripts/selinux/README @@ -0,0 +1,2 @@ +Please see Documentation/SELinux.txt for information on +installing a dummy SELinux policy. diff --git a/scripts/selinux/install_policy.sh b/scripts/selinux/install_policy.sh new file mode 100644 index 000000000000..7b9ccf61f8f9 --- /dev/null +++ b/scripts/selinux/install_policy.sh @@ -0,0 +1,69 @@ +#!/bin/sh +if [ `id -u` -ne 0 ]; then + echo "$0: must be root to install the selinux policy" + exit 1 +fi +SF=`which setfiles` +if [ $? -eq 1 ]; then + if [ -f /sbin/setfiles ]; then + SF="/usr/setfiles" + else + echo "no selinux tools installed: setfiles" + exit 1 + fi +fi + +cd mdp + +CP=`which checkpolicy` +VERS=`$CP -V | awk '{print $1}'` + +./mdp policy.conf file_contexts +$CP -o policy.$VERS policy.conf + +mkdir -p /etc/selinux/dummy/policy +mkdir -p /etc/selinux/dummy/contexts/files + +cp file_contexts /etc/selinux/dummy/contexts/files +cp dbus_contexts /etc/selinux/dummy/contexts +cp policy.$VERS /etc/selinux/dummy/policy +FC_FILE=/etc/selinux/dummy/contexts/files/file_contexts + +if [ ! -d /etc/selinux ]; then + mkdir -p /etc/selinux +fi +if [ ! -f /etc/selinux/config ]; then + cat > /etc/selinux/config << EOF +SELINUX=enforcing +SELINUXTYPE=dummy +EOF +else + TYPE=`cat /etc/selinux/config | grep "^SELINUXTYPE" | tail -1 | awk -F= '{ print $2 '}` + if [ "eq$TYPE" != "eqdummy" ]; then + selinuxenabled + if [ $? -eq 0 ]; then + echo "SELinux already enabled with a non-dummy policy." + echo "Exiting. Please install policy by hand if that" + echo "is what you REALLY want." + exit 1 + fi + mv /etc/selinux/config /etc/selinux/config.mdpbak + grep -v "^SELINUXTYPE" /etc/selinux/config.mdpbak >> /etc/selinux/config + echo "SELINUXTYPE=dummy" >> /etc/selinux/config + fi +fi + +cd /etc/selinux/dummy/contexts/files +$SF file_contexts / + +mounts=`cat /proc/$$/mounts | egrep "ext2|ext3|xfs|jfs|ext4|ext4dev|gfs2" | awk '{ print $2 '}` +$SF file_contexts $mounts + + +dodev=`cat /proc/$$/mounts | grep "/dev "` +if [ "eq$dodev" != "eq" ]; then + mount --move /dev /mnt + $SF file_contexts /dev + mount --move /mnt /dev +fi + diff --git a/scripts/selinux/mdp/Makefile b/scripts/selinux/mdp/Makefile new file mode 100644 index 000000000000..eb365b333441 --- /dev/null +++ b/scripts/selinux/mdp/Makefile @@ -0,0 +1,5 @@ +hostprogs-y := mdp +HOST_EXTRACFLAGS += -Isecurity/selinux/include + +always := $(hostprogs-y) +clean-files := $(hostprogs-y) policy.* file_contexts diff --git a/scripts/selinux/mdp/dbus_contexts b/scripts/selinux/mdp/dbus_contexts new file mode 100644 index 000000000000..116e684f9fc1 --- /dev/null +++ b/scripts/selinux/mdp/dbus_contexts @@ -0,0 +1,6 @@ + + + + + diff --git a/scripts/selinux/mdp/mdp.c b/scripts/selinux/mdp/mdp.c new file mode 100644 index 000000000000..ca757d486187 --- /dev/null +++ b/scripts/selinux/mdp/mdp.c @@ -0,0 +1,242 @@ +/* + * + * mdp - make dummy policy + * + * When pointed at a kernel tree, builds a dummy policy for that kernel + * with exactly one type with full rights to itself. + * + * 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 2 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, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Copyright (C) IBM Corporation, 2006 + * + * Authors: Serge E. Hallyn + */ + +#include +#include +#include +#include + +#include "flask.h" + +void usage(char *name) +{ + printf("usage: %s [-m] policy_file context_file\n", name); + exit(1); +} + +void find_common_name(char *cname, char *dest, int len) +{ + char *start, *end; + + start = strchr(cname, '_')+1; + end = strchr(start, '_'); + if (!start || !end || start-cname > len || end-start > len) { + printf("Error with commons defines\n"); + exit(1); + } + strncpy(dest, start, end-start); + dest[end-start] = '\0'; +} + +#define S_(x) x, +static char *classlist[] = { +#include "class_to_string.h" + NULL +}; +#undef S_ + +#include "initial_sid_to_string.h" + +#define TB_(x) char *x[] = { +#define TE_(x) NULL }; +#define S_(x) x, +#include "common_perm_to_string.h" +#undef TB_ +#undef TE_ +#undef S_ + +struct common { + char *cname; + char **perms; +}; +struct common common[] = { +#define TB_(x) { #x, x }, +#define S_(x) +#define TE_(x) +#include "common_perm_to_string.h" +#undef TB_ +#undef TE_ +#undef S_ +}; + +#define S_(x, y, z) {x, #y}, +struct av_inherit { + int class; + char *common; +}; +struct av_inherit av_inherit[] = { +#include "av_inherit.h" +}; +#undef S_ + +#include "av_permissions.h" +#define S_(x, y, z) {x, y, z}, +struct av_perms { + int class; + int perm_i; + char *perm_s; +}; +struct av_perms av_perms[] = { +#include "av_perm_to_string.h" +}; +#undef S_ + +int main(int argc, char *argv[]) +{ + int i, j, mls = 0; + char **arg, *polout, *ctxout; + int classlist_len, initial_sid_to_string_len; + FILE *fout; + + if (argc < 3) + usage(argv[0]); + arg = argv+1; + if (argc==4 && strcmp(argv[1], "-m") == 0) { + mls = 1; + arg++; + } + polout = *arg++; + ctxout = *arg; + + fout = fopen(polout, "w"); + if (!fout) { + printf("Could not open %s for writing\n", polout); + usage(argv[0]); + } + + classlist_len = sizeof(classlist) / sizeof(char *); + /* print out the classes */ + for (i=1; i < classlist_len; i++) { + if(classlist[i]) + fprintf(fout, "class %s\n", classlist[i]); + else + fprintf(fout, "class user%d\n", i); + } + fprintf(fout, "\n"); + + initial_sid_to_string_len = sizeof(initial_sid_to_string) / sizeof (char *); + /* print out the sids */ + for (i=1; i < initial_sid_to_string_len; i++) + fprintf(fout, "sid %s\n", initial_sid_to_string[i]); + fprintf(fout, "\n"); + + /* print out the commons */ + for (i=0; i< sizeof(common)/sizeof(struct common); i++) { + char cname[101]; + find_common_name(common[i].cname, cname, 100); + cname[100] = '\0'; + fprintf(fout, "common %s\n{\n", cname); + for (j=0; common[i].perms[j]; j++) + fprintf(fout, "\t%s\n", common[i].perms[j]); + fprintf(fout, "}\n\n"); + } + fprintf(fout, "\n"); + + /* print out the class permissions */ + for (i=1; i < classlist_len; i++) { + if (classlist[i]) { + int firstperm = -1, numperms = 0; + + fprintf(fout, "class %s\n", classlist[i]); + /* does it inherit from a common? */ + for (j=0; j < sizeof(av_inherit)/sizeof(struct av_inherit); j++) + if (av_inherit[j].class == i) + fprintf(fout, "inherits %s\n", av_inherit[j].common); + + for (j=0; j < sizeof(av_perms)/sizeof(struct av_perms); j++) { + if (av_perms[j].class == i) { + if (firstperm == -1) + firstperm = j; + numperms++; + } + } + if (!numperms) { + fprintf(fout, "\n"); + continue; + } + + fprintf(fout, "{\n"); + /* print out the av_perms */ + for (j=0; j < numperms; j++) { + fprintf(fout, "\t%s\n", av_perms[firstperm+j].perm_s); + } + fprintf(fout, "}\n\n"); + } + } + fprintf(fout, "\n"); + + /* NOW PRINT OUT MLS STUFF */ + if (mls) { + printf("MLS not yet implemented\n"); + exit(1); + } + + /* types, roles, and allows */ + fprintf(fout, "type base_t;\n"); + fprintf(fout, "role base_r types { base_t };\n"); + for (i=1; i < classlist_len; i++) { + if (classlist[i]) + fprintf(fout, "allow base_t base_t:%s *;\n", classlist[i]); + else + fprintf(fout, "allow base_t base_t:user%d *;\n", i); + } + fprintf(fout, "user user_u roles { base_r };\n"); + fprintf(fout, "\n"); + + /* default sids */ + for (i=1; i < initial_sid_to_string_len; i++) + fprintf(fout, "sid %s user_u:base_r:base_t\n", initial_sid_to_string[i]); + fprintf(fout, "\n"); + + + fprintf(fout, "fs_use_xattr ext2 user_u:base_r:base_t;\n"); + fprintf(fout, "fs_use_xattr ext3 user_u:base_r:base_t;\n"); + fprintf(fout, "fs_use_xattr jfs user_u:base_r:base_t;\n"); + fprintf(fout, "fs_use_xattr xfs user_u:base_r:base_t;\n"); + fprintf(fout, "fs_use_xattr reiserfs user_u:base_r:base_t;\n"); + + fprintf(fout, "fs_use_task pipefs user_u:base_r:base_t;\n"); + fprintf(fout, "fs_use_task sockfs user_u:base_r:base_t;\n"); + + fprintf(fout, "fs_use_trans devpts user_u:base_r:base_t;\n"); + fprintf(fout, "fs_use_trans tmpfs user_u:base_r:base_t;\n"); + fprintf(fout, "fs_use_trans shm user_u:base_r:base_t;\n"); + + fprintf(fout, "genfscon proc / user_u:base_r:base_t\n"); + + fclose(fout); + + fout = fopen(ctxout, "w"); + if (!fout) { + printf("Wrote policy, but cannot open %s for writing\n", ctxout); + usage(argv[0]); + } + fprintf(fout, "/ user_u:base_r:base_t\n"); + fprintf(fout, "/.* user_u:base_r:base_t\n"); + fclose(fout); + + return 0; +} From da31894ed7b654e2e1741e7ac4ef6c15be0dd14b Mon Sep 17 00:00:00 2001 From: Eric Paris Date: Fri, 22 Aug 2008 11:35:57 -0400 Subject: [PATCH 10/16] securityfs: do not depend on CONFIG_SECURITY Add a new Kconfig option SECURITYFS which will build securityfs support but does not require CONFIG_SECURITY. The only current user of securityfs does not depend on CONFIG_SECURITY and there is no reason the full LSM needs to be built to build this fs. Signed-off-by: Eric Paris Signed-off-by: James Morris --- drivers/char/tpm/Kconfig | 1 + include/linux/security.h | 54 ++++++++++++++++++++++------------------ security/Kconfig | 8 ++++++ security/Makefile | 3 ++- 4 files changed, 41 insertions(+), 25 deletions(-) diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig index 3738cfa209ff..f5fc64f89c5c 100644 --- a/drivers/char/tpm/Kconfig +++ b/drivers/char/tpm/Kconfig @@ -6,6 +6,7 @@ menuconfig TCG_TPM tristate "TPM Hardware Support" depends on HAS_IOMEM depends on EXPERIMENTAL + select SECURITYFS ---help--- If you have a TPM security chip in your system, which implements the Trusted Computing Group's specification, diff --git a/include/linux/security.h b/include/linux/security.h index 80c4d002864c..f5c4a51eb42e 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -1560,11 +1560,6 @@ struct security_operations { extern int security_init(void); extern int security_module_enable(struct security_operations *ops); extern int register_security(struct security_operations *ops); -extern struct dentry *securityfs_create_file(const char *name, mode_t mode, - struct dentry *parent, void *data, - const struct file_operations *fops); -extern struct dentry *securityfs_create_dir(const char *name, struct dentry *parent); -extern void securityfs_remove(struct dentry *dentry); /* Security operations */ int security_ptrace_may_access(struct task_struct *child, unsigned int mode); @@ -2424,25 +2419,6 @@ static inline int security_netlink_recv(struct sk_buff *skb, int cap) return cap_netlink_recv(skb, cap); } -static inline struct dentry *securityfs_create_dir(const char *name, - struct dentry *parent) -{ - return ERR_PTR(-ENODEV); -} - -static inline struct dentry *securityfs_create_file(const char *name, - mode_t mode, - struct dentry *parent, - void *data, - const struct file_operations *fops) -{ - return ERR_PTR(-ENODEV); -} - -static inline void securityfs_remove(struct dentry *dentry) -{ -} - static inline int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) { return -EOPNOTSUPP; @@ -2806,5 +2782,35 @@ static inline void security_audit_rule_free(void *lsmrule) #endif /* CONFIG_SECURITY */ #endif /* CONFIG_AUDIT */ +#ifdef CONFIG_SECURITYFS + +extern struct dentry *securityfs_create_file(const char *name, mode_t mode, + struct dentry *parent, void *data, + const struct file_operations *fops); +extern struct dentry *securityfs_create_dir(const char *name, struct dentry *parent); +extern void securityfs_remove(struct dentry *dentry); + +#else /* CONFIG_SECURITYFS */ + +static inline struct dentry *securityfs_create_dir(const char *name, + struct dentry *parent) +{ + return ERR_PTR(-ENODEV); +} + +static inline struct dentry *securityfs_create_file(const char *name, + mode_t mode, + struct dentry *parent, + void *data, + const struct file_operations *fops) +{ + return ERR_PTR(-ENODEV); +} + +static inline void securityfs_remove(struct dentry *dentry) +{} + +#endif + #endif /* ! __LINUX_SECURITY_H */ diff --git a/security/Kconfig b/security/Kconfig index 559293922a47..d9f47ce7e207 100644 --- a/security/Kconfig +++ b/security/Kconfig @@ -51,6 +51,14 @@ config SECURITY If you are unsure how to answer this question, answer N. +config SECURITYFS + bool "Enable the securityfs filesystem" + help + This will build the securityfs filesystem. It is currently used by + the TPM bios character driver. It is not used by SELinux or SMACK. + + If you are unsure how to answer this question, answer N. + config SECURITY_NETWORK bool "Socket and Networking Security Hooks" depends on SECURITY diff --git a/security/Makefile b/security/Makefile index f65426099aa6..c05c127fff9a 100644 --- a/security/Makefile +++ b/security/Makefile @@ -10,7 +10,8 @@ subdir-$(CONFIG_SECURITY_SMACK) += smack obj-y += commoncap.o # Object file lists -obj-$(CONFIG_SECURITY) += security.o capability.o inode.o +obj-$(CONFIG_SECURITY) += security.o capability.o +obj-$(CONFIG_SECURITYFS) += inode.o # Must precede capability.o in order to stack properly. obj-$(CONFIG_SECURITY_SELINUX) += selinux/built-in.o obj-$(CONFIG_SECURITY_SMACK) += smack/built-in.o From d9250dea3f89fe808a525f08888016b495240ed4 Mon Sep 17 00:00:00 2001 From: KaiGai Kohei Date: Thu, 28 Aug 2008 16:35:57 +0900 Subject: [PATCH 11/16] SELinux: add boundary support and thread context assignment The purpose of this patch is to assign per-thread security context under a constraint. It enables multi-threaded server application to kick a request handler with its fair security context, and helps some of userspace object managers to handle user's request. When we assign a per-thread security context, it must not have wider permissions than the original one. Because a multi-threaded process shares a single local memory, an arbitary per-thread security context also means another thread can easily refer violated information. The constraint on a per-thread security context requires a new domain has to be equal or weaker than its original one, when it tries to assign a per-thread security context. Bounds relationship between two types is a way to ensure a domain can never have wider permission than its bounds. We can define it in two explicit or implicit ways. The first way is using new TYPEBOUNDS statement. It enables to define a boundary of types explicitly. The other one expand the concept of existing named based hierarchy. If we defines a type with "." separated name like "httpd_t.php", toolchain implicitly set its bounds on "httpd_t". This feature requires a new policy version. The 24th version (POLICYDB_VERSION_BOUNDARY) enables to ship them into kernel space, and the following patch enables to handle it. Signed-off-by: KaiGai Kohei Acked-by: Stephen Smalley Signed-off-by: James Morris --- security/selinux/avc.c | 2 +- security/selinux/hooks.c | 15 +- security/selinux/include/avc.h | 4 + security/selinux/include/security.h | 15 +- security/selinux/ss/policydb.c | 205 ++++++++++++++++++++++++++-- security/selinux/ss/policydb.h | 5 + security/selinux/ss/services.c | 172 ++++++++++++++++++++++- 7 files changed, 398 insertions(+), 20 deletions(-) diff --git a/security/selinux/avc.c b/security/selinux/avc.c index 114b4b4c97b2..cb30c7e350b3 100644 --- a/security/selinux/avc.c +++ b/security/selinux/avc.c @@ -136,7 +136,7 @@ static inline int avc_hash(u32 ssid, u32 tsid, u16 tclass) * @tclass: target security class * @av: access vector */ -static void avc_dump_av(struct audit_buffer *ab, u16 tclass, u32 av) +void avc_dump_av(struct audit_buffer *ab, u16 tclass, u32 av) { const char **common_pts = NULL; u32 common_base = 0; diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 6b5790bba8f9..89f446d86054 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -5226,8 +5226,12 @@ static int selinux_setprocattr(struct task_struct *p, if (sid == 0) return -EINVAL; - - /* Only allow single threaded processes to change context */ + /* + * SELinux allows to change context in the following case only. + * - Single threaded processes. + * - Multi threaded processes intend to change its context into + * more restricted domain (defined by TYPEBOUNDS statement). + */ if (atomic_read(&p->mm->mm_users) != 1) { struct task_struct *g, *t; struct mm_struct *mm = p->mm; @@ -5235,11 +5239,16 @@ static int selinux_setprocattr(struct task_struct *p, do_each_thread(g, t) { if (t->mm == mm && t != p) { read_unlock(&tasklist_lock); - return -EPERM; + error = security_bounded_transition(tsec->sid, sid); + if (!error) + goto boundary_ok; + + return error; } } while_each_thread(g, t); read_unlock(&tasklist_lock); } +boundary_ok: /* Check permissions for the transition. */ error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, diff --git a/security/selinux/include/avc.h b/security/selinux/include/avc.h index 7b9769f5e775..d12ff1a9c0aa 100644 --- a/security/selinux/include/avc.h +++ b/security/selinux/include/avc.h @@ -12,6 +12,7 @@ #include #include #include +#include #include #include #include @@ -126,6 +127,9 @@ int avc_add_callback(int (*callback)(u32 event, u32 ssid, u32 tsid, u32 events, u32 ssid, u32 tsid, u16 tclass, u32 perms); +/* Shows permission in human readable form */ +void avc_dump_av(struct audit_buffer *ab, u16 tclass, u32 av); + /* Exported to selinuxfs */ int avc_get_hash_stats(char *page); extern unsigned int avc_cache_threshold; diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h index 7c543003d653..72447370bc95 100644 --- a/security/selinux/include/security.h +++ b/security/selinux/include/security.h @@ -27,13 +27,14 @@ #define POLICYDB_VERSION_RANGETRANS 21 #define POLICYDB_VERSION_POLCAP 22 #define POLICYDB_VERSION_PERMISSIVE 23 +#define POLICYDB_VERSION_BOUNDARY 24 /* Range of policy versions we understand*/ #define POLICYDB_VERSION_MIN POLICYDB_VERSION_BASE #ifdef CONFIG_SECURITY_SELINUX_POLICYDB_VERSION_MAX #define POLICYDB_VERSION_MAX CONFIG_SECURITY_SELINUX_POLICYDB_VERSION_MAX_VALUE #else -#define POLICYDB_VERSION_MAX POLICYDB_VERSION_PERMISSIVE +#define POLICYDB_VERSION_MAX POLICYDB_VERSION_BOUNDARY #endif #define CONTEXT_MNT 0x01 @@ -62,6 +63,16 @@ enum { extern int selinux_policycap_netpeer; extern int selinux_policycap_openperm; +/* + * type_datum properties + * available at the kernel policy version >= POLICYDB_VERSION_BOUNDARY + */ +#define TYPEDATUM_PROPERTY_PRIMARY 0x0001 +#define TYPEDATUM_PROPERTY_ATTRIBUTE 0x0002 + +/* limitation of boundary depth */ +#define POLICYDB_BOUNDS_MAXDEPTH 4 + int security_load_policy(void *data, size_t len); int security_policycap_supported(unsigned int req_cap); @@ -117,6 +128,8 @@ int security_node_sid(u16 domain, void *addr, u32 addrlen, int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid, u16 tclass); +int security_bounded_transition(u32 oldsid, u32 newsid); + int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid); int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type, diff --git a/security/selinux/ss/policydb.c b/security/selinux/ss/policydb.c index 26646305dc0e..72e4a54973aa 100644 --- a/security/selinux/ss/policydb.c +++ b/security/selinux/ss/policydb.c @@ -30,6 +30,7 @@ #include #include #include +#include #include "security.h" #include "policydb.h" @@ -116,7 +117,12 @@ static struct policydb_compat_info policydb_compat[] = { .version = POLICYDB_VERSION_PERMISSIVE, .sym_num = SYM_NUM, .ocon_num = OCON_NUM, - } + }, + { + .version = POLICYDB_VERSION_BOUNDARY, + .sym_num = SYM_NUM, + .ocon_num = OCON_NUM, + }, }; static struct policydb_compat_info *policydb_lookup_compat(int version) @@ -254,7 +260,9 @@ static int role_index(void *key, void *datum, void *datap) role = datum; p = datap; - if (!role->value || role->value > p->p_roles.nprim) + if (!role->value + || role->value > p->p_roles.nprim + || role->bounds > p->p_roles.nprim) return -EINVAL; p->p_role_val_to_name[role->value - 1] = key; p->role_val_to_struct[role->value - 1] = role; @@ -270,9 +278,12 @@ static int type_index(void *key, void *datum, void *datap) p = datap; if (typdatum->primary) { - if (!typdatum->value || typdatum->value > p->p_types.nprim) + if (!typdatum->value + || typdatum->value > p->p_types.nprim + || typdatum->bounds > p->p_types.nprim) return -EINVAL; p->p_type_val_to_name[typdatum->value - 1] = key; + p->type_val_to_struct[typdatum->value - 1] = typdatum; } return 0; @@ -285,7 +296,9 @@ static int user_index(void *key, void *datum, void *datap) usrdatum = datum; p = datap; - if (!usrdatum->value || usrdatum->value > p->p_users.nprim) + if (!usrdatum->value + || usrdatum->value > p->p_users.nprim + || usrdatum->bounds > p->p_users.nprim) return -EINVAL; p->p_user_val_to_name[usrdatum->value - 1] = key; p->user_val_to_struct[usrdatum->value - 1] = usrdatum; @@ -438,6 +451,14 @@ static int policydb_index_others(struct policydb *p) goto out; } + p->type_val_to_struct = + kmalloc(p->p_types.nprim * sizeof(*(p->type_val_to_struct)), + GFP_KERNEL); + if (!p->type_val_to_struct) { + rc = -ENOMEM; + goto out; + } + if (cond_init_bool_indexes(p)) { rc = -ENOMEM; goto out; @@ -625,6 +646,7 @@ void policydb_destroy(struct policydb *p) kfree(p->class_val_to_struct); kfree(p->role_val_to_struct); kfree(p->user_val_to_struct); + kfree(p->type_val_to_struct); avtab_destroy(&p->te_avtab); @@ -1176,8 +1198,8 @@ static int role_read(struct policydb *p, struct hashtab *h, void *fp) { char *key = NULL; struct role_datum *role; - int rc; - __le32 buf[2]; + int rc, to_read = 2; + __le32 buf[3]; u32 len; role = kzalloc(sizeof(*role), GFP_KERNEL); @@ -1186,12 +1208,17 @@ static int role_read(struct policydb *p, struct hashtab *h, void *fp) goto out; } - rc = next_entry(buf, fp, sizeof buf); + if (p->policyvers >= POLICYDB_VERSION_BOUNDARY) + to_read = 3; + + rc = next_entry(buf, fp, sizeof(buf[0]) * to_read); if (rc < 0) goto bad; len = le32_to_cpu(buf[0]); role->value = le32_to_cpu(buf[1]); + if (p->policyvers >= POLICYDB_VERSION_BOUNDARY) + role->bounds = le32_to_cpu(buf[2]); key = kmalloc(len + 1, GFP_KERNEL); if (!key) { @@ -1236,8 +1263,8 @@ static int type_read(struct policydb *p, struct hashtab *h, void *fp) { char *key = NULL; struct type_datum *typdatum; - int rc; - __le32 buf[3]; + int rc, to_read = 3; + __le32 buf[4]; u32 len; typdatum = kzalloc(sizeof(*typdatum), GFP_KERNEL); @@ -1246,13 +1273,27 @@ static int type_read(struct policydb *p, struct hashtab *h, void *fp) return rc; } - rc = next_entry(buf, fp, sizeof buf); + if (p->policyvers >= POLICYDB_VERSION_BOUNDARY) + to_read = 4; + + rc = next_entry(buf, fp, sizeof(buf[0]) * to_read); if (rc < 0) goto bad; len = le32_to_cpu(buf[0]); typdatum->value = le32_to_cpu(buf[1]); - typdatum->primary = le32_to_cpu(buf[2]); + if (p->policyvers >= POLICYDB_VERSION_BOUNDARY) { + u32 prop = le32_to_cpu(buf[2]); + + if (prop & TYPEDATUM_PROPERTY_PRIMARY) + typdatum->primary = 1; + if (prop & TYPEDATUM_PROPERTY_ATTRIBUTE) + typdatum->attribute = 1; + + typdatum->bounds = le32_to_cpu(buf[3]); + } else { + typdatum->primary = le32_to_cpu(buf[2]); + } key = kmalloc(len + 1, GFP_KERNEL); if (!key) { @@ -1309,8 +1350,8 @@ static int user_read(struct policydb *p, struct hashtab *h, void *fp) { char *key = NULL; struct user_datum *usrdatum; - int rc; - __le32 buf[2]; + int rc, to_read = 2; + __le32 buf[3]; u32 len; usrdatum = kzalloc(sizeof(*usrdatum), GFP_KERNEL); @@ -1319,12 +1360,17 @@ static int user_read(struct policydb *p, struct hashtab *h, void *fp) goto out; } - rc = next_entry(buf, fp, sizeof buf); + if (p->policyvers >= POLICYDB_VERSION_BOUNDARY) + to_read = 3; + + rc = next_entry(buf, fp, sizeof(buf[0]) * to_read); if (rc < 0) goto bad; len = le32_to_cpu(buf[0]); usrdatum->value = le32_to_cpu(buf[1]); + if (p->policyvers >= POLICYDB_VERSION_BOUNDARY) + usrdatum->bounds = le32_to_cpu(buf[2]); key = kmalloc(len + 1, GFP_KERNEL); if (!key) { @@ -1465,6 +1511,133 @@ static int (*read_f[SYM_NUM]) (struct policydb *p, struct hashtab *h, void *fp) cat_read, }; +static int user_bounds_sanity_check(void *key, void *datum, void *datap) +{ + struct user_datum *upper, *user; + struct policydb *p = datap; + int depth = 0; + + upper = user = datum; + while (upper->bounds) { + struct ebitmap_node *node; + unsigned long bit; + + if (++depth == POLICYDB_BOUNDS_MAXDEPTH) { + printk(KERN_ERR "SELinux: user %s: " + "too deep or looped boundary", + (char *) key); + return -EINVAL; + } + + upper = p->user_val_to_struct[upper->bounds - 1]; + ebitmap_for_each_positive_bit(&user->roles, node, bit) { + if (ebitmap_get_bit(&upper->roles, bit)) + continue; + + printk(KERN_ERR + "SELinux: boundary violated policy: " + "user=%s role=%s bounds=%s\n", + p->p_user_val_to_name[user->value - 1], + p->p_role_val_to_name[bit], + p->p_user_val_to_name[upper->value - 1]); + + return -EINVAL; + } + } + + return 0; +} + +static int role_bounds_sanity_check(void *key, void *datum, void *datap) +{ + struct role_datum *upper, *role; + struct policydb *p = datap; + int depth = 0; + + upper = role = datum; + while (upper->bounds) { + struct ebitmap_node *node; + unsigned long bit; + + if (++depth == POLICYDB_BOUNDS_MAXDEPTH) { + printk(KERN_ERR "SELinux: role %s: " + "too deep or looped bounds\n", + (char *) key); + return -EINVAL; + } + + upper = p->role_val_to_struct[upper->bounds - 1]; + ebitmap_for_each_positive_bit(&role->types, node, bit) { + if (ebitmap_get_bit(&upper->types, bit)) + continue; + + printk(KERN_ERR + "SELinux: boundary violated policy: " + "role=%s type=%s bounds=%s\n", + p->p_role_val_to_name[role->value - 1], + p->p_type_val_to_name[bit], + p->p_role_val_to_name[upper->value - 1]); + + return -EINVAL; + } + } + + return 0; +} + +static int type_bounds_sanity_check(void *key, void *datum, void *datap) +{ + struct type_datum *upper, *type; + struct policydb *p = datap; + int depth = 0; + + upper = type = datum; + while (upper->bounds) { + if (++depth == POLICYDB_BOUNDS_MAXDEPTH) { + printk(KERN_ERR "SELinux: type %s: " + "too deep or looped boundary\n", + (char *) key); + return -EINVAL; + } + + upper = p->type_val_to_struct[upper->bounds - 1]; + if (upper->attribute) { + printk(KERN_ERR "SELinux: type %s: " + "bounded by attribute %s", + (char *) key, + p->p_type_val_to_name[upper->value - 1]); + return -EINVAL; + } + } + + return 0; +} + +static int policydb_bounds_sanity_check(struct policydb *p) +{ + int rc; + + if (p->policyvers < POLICYDB_VERSION_BOUNDARY) + return 0; + + rc = hashtab_map(p->p_users.table, + user_bounds_sanity_check, p); + if (rc) + return rc; + + rc = hashtab_map(p->p_roles.table, + role_bounds_sanity_check, p); + if (rc) + return rc; + + rc = hashtab_map(p->p_types.table, + type_bounds_sanity_check, p); + if (rc) + return rc; + + return 0; +} + extern int ss_initialized; /* @@ -1961,6 +2134,10 @@ int policydb_read(struct policydb *p, void *fp) goto bad; } + rc = policydb_bounds_sanity_check(p); + if (rc) + goto bad; + rc = 0; out: return rc; diff --git a/security/selinux/ss/policydb.h b/security/selinux/ss/policydb.h index 4253370fda6a..55152d498b53 100644 --- a/security/selinux/ss/policydb.h +++ b/security/selinux/ss/policydb.h @@ -61,6 +61,7 @@ struct class_datum { /* Role attributes */ struct role_datum { u32 value; /* internal role value */ + u32 bounds; /* boundary of role */ struct ebitmap dominates; /* set of roles dominated by this role */ struct ebitmap types; /* set of authorized types for role */ }; @@ -81,12 +82,15 @@ struct role_allow { /* Type attributes */ struct type_datum { u32 value; /* internal type value */ + u32 bounds; /* boundary of type */ unsigned char primary; /* primary name? */ + unsigned char attribute;/* attribute ?*/ }; /* User attributes */ struct user_datum { u32 value; /* internal user value */ + u32 bounds; /* bounds of user */ struct ebitmap roles; /* set of authorized roles for user */ struct mls_range range; /* MLS range (min - max) for user */ struct mls_level dfltlevel; /* default login MLS level for user */ @@ -209,6 +213,7 @@ struct policydb { struct class_datum **class_val_to_struct; struct role_datum **role_val_to_struct; struct user_datum **user_val_to_struct; + struct type_datum **type_val_to_struct; /* type enforcement access vectors and transitions */ struct avtab te_avtab; diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index 5a0536bddc63..4f233d9960e7 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -88,6 +88,11 @@ static u32 latest_granting; static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len); +static int context_struct_compute_av(struct context *scontext, + struct context *tcontext, + u16 tclass, + u32 requested, + struct av_decision *avd); /* * Return the boolean value of a constraint expression * when it is applied to the specified source and target @@ -273,6 +278,100 @@ mls_ops: return s[0]; } +/* + * security_boundary_permission - drops violated permissions + * on boundary constraint. + */ +static void type_attribute_bounds_av(struct context *scontext, + struct context *tcontext, + u16 tclass, + u32 requested, + struct av_decision *avd) +{ + struct context lo_scontext; + struct context lo_tcontext; + struct av_decision lo_avd; + struct type_datum *source + = policydb.type_val_to_struct[scontext->type - 1]; + struct type_datum *target + = policydb.type_val_to_struct[tcontext->type - 1]; + u32 masked = 0; + + if (source->bounds) { + memset(&lo_avd, 0, sizeof(lo_avd)); + + memcpy(&lo_scontext, scontext, sizeof(lo_scontext)); + lo_scontext.type = source->bounds; + + context_struct_compute_av(&lo_scontext, + tcontext, + tclass, + requested, + &lo_avd); + if ((lo_avd.allowed & avd->allowed) == avd->allowed) + return; /* no masked permission */ + masked = ~lo_avd.allowed & avd->allowed; + } + + if (target->bounds) { + memset(&lo_avd, 0, sizeof(lo_avd)); + + memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext)); + lo_tcontext.type = target->bounds; + + context_struct_compute_av(scontext, + &lo_tcontext, + tclass, + requested, + &lo_avd); + if ((lo_avd.allowed & avd->allowed) == avd->allowed) + return; /* no masked permission */ + masked = ~lo_avd.allowed & avd->allowed; + } + + if (source->bounds && target->bounds) { + memset(&lo_avd, 0, sizeof(lo_avd)); + /* + * lo_scontext and lo_tcontext are already + * set up. + */ + + context_struct_compute_av(&lo_scontext, + &lo_tcontext, + tclass, + requested, + &lo_avd); + if ((lo_avd.allowed & avd->allowed) == avd->allowed) + return; /* no masked permission */ + masked = ~lo_avd.allowed & avd->allowed; + } + + if (masked) { + struct audit_buffer *ab; + char *stype_name + = policydb.p_type_val_to_name[source->value - 1]; + char *ttype_name + = policydb.p_type_val_to_name[target->value - 1]; + char *tclass_name + = policydb.p_class_val_to_name[tclass - 1]; + + /* mask violated permissions */ + avd->allowed &= ~masked; + + /* notice to userspace via audit message */ + ab = audit_log_start(current->audit_context, + GFP_ATOMIC, AUDIT_SELINUX_ERR); + if (!ab) + return; + + audit_log_format(ab, "av boundary violation: " + "source=%s target=%s tclass=%s", + stype_name, ttype_name, tclass_name); + avc_dump_av(ab, tclass, masked); + audit_log_end(ab); + } +} + /* * Compute access vectors based on a context structure pair for * the permissions in a particular class. @@ -404,6 +503,14 @@ static int context_struct_compute_av(struct context *scontext, PROCESS__DYNTRANSITION); } + /* + * If the given source and target types have boundary + * constraint, lazy checks have to mask any violated + * permission and notice it to userspace via audit. + */ + type_attribute_bounds_av(scontext, tcontext, + tclass, requested, avd); + return 0; inval_class: @@ -549,6 +656,69 @@ out: return rc; } +/* + * security_bounded_transition - check whether the given + * transition is directed to bounded, or not. + * It returns 0, if @newsid is bounded by @oldsid. + * Otherwise, it returns error code. + * + * @oldsid : current security identifier + * @newsid : destinated security identifier + */ +int security_bounded_transition(u32 old_sid, u32 new_sid) +{ + struct context *old_context, *new_context; + struct type_datum *type; + int index; + int rc = -EINVAL; + + read_lock(&policy_rwlock); + + old_context = sidtab_search(&sidtab, old_sid); + if (!old_context) { + printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n", + __func__, old_sid); + goto out; + } + + new_context = sidtab_search(&sidtab, new_sid); + if (!new_context) { + printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n", + __func__, new_sid); + goto out; + } + + /* type/domain unchaned */ + if (old_context->type == new_context->type) { + rc = 0; + goto out; + } + + index = new_context->type; + while (true) { + type = policydb.type_val_to_struct[index - 1]; + BUG_ON(!type); + + /* not bounded anymore */ + if (!type->bounds) { + rc = -EPERM; + break; + } + + /* @newsid is bounded by @oldsid */ + if (type->bounds == old_context->type) { + rc = 0; + break; + } + index = type->bounds; + } +out: + read_unlock(&policy_rwlock); + + return rc; +} + + /** * security_compute_av - Compute access vector decisions. * @ssid: source security identifier @@ -794,7 +964,7 @@ static int string_to_context_struct(struct policydb *pol, *p++ = 0; typdatum = hashtab_search(pol->p_types.table, scontextp); - if (!typdatum) + if (!typdatum || typdatum->attribute) goto out; ctx->type = typdatum->value; From b56c8c221d192e4ffa719d00907c3b60fbaa2737 Mon Sep 17 00:00:00 2001 From: James Morris Date: Fri, 5 Sep 2008 21:43:38 +1000 Subject: [PATCH 12/16] SELinux: add gitignore file for mdp script Add gitignore file for scripts/selinux/mdp/mdp. Signed-off-by: James Morris --- scripts/selinux/mdp/.gitignore | 2 ++ 1 file changed, 2 insertions(+) create mode 100644 scripts/selinux/mdp/.gitignore diff --git a/scripts/selinux/mdp/.gitignore b/scripts/selinux/mdp/.gitignore new file mode 100644 index 000000000000..654546d8dffd --- /dev/null +++ b/scripts/selinux/mdp/.gitignore @@ -0,0 +1,2 @@ +# Generated file +mdp From f058925b201357fba48d56cc9c1719ae274b2022 Mon Sep 17 00:00:00 2001 From: Stephen Smalley Date: Thu, 11 Sep 2008 09:20:26 -0400 Subject: [PATCH 13/16] Update selinux info in MAINTAINERS and Kconfig help text Update the SELinux entry in MAINTAINERS and drop the obsolete information from the selinux Kconfig help text. Signed-off-by: Stephen Smalley Signed-off-by: James Morris --- MAINTAINERS | 3 ++- security/selinux/Kconfig | 3 --- 2 files changed, 2 insertions(+), 4 deletions(-) diff --git a/MAINTAINERS b/MAINTAINERS index 28c69aaefcd9..5abb23e09fdc 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3644,7 +3644,8 @@ P: Eric Paris M: eparis@parisplace.org L: linux-kernel@vger.kernel.org (kernel issues) L: selinux@tycho.nsa.gov (subscribers-only, general discussion) -W: http://www.nsa.gov/selinux +W: http://selinuxproject.org +T: git kernel.org:pub/scm/linux/kernel/git/jmorris/security-testing-2.6.git S: Supported SENSABLE PHANTOM diff --git a/security/selinux/Kconfig b/security/selinux/Kconfig index a436d1cfa88b..26301dd651d3 100644 --- a/security/selinux/Kconfig +++ b/security/selinux/Kconfig @@ -6,9 +6,6 @@ config SECURITY_SELINUX help This selects NSA Security-Enhanced Linux (SELinux). You will also need a policy configuration and a labeled filesystem. - You can obtain the policy compiler (checkpolicy), the utility for - labeling filesystems (setfiles), and an example policy configuration - from . If you are unsure how to answer this question, answer N. config SECURITY_SELINUX_BOOTPARAM From de45e806a84909648623119dfe6fc1d31e71ceba Mon Sep 17 00:00:00 2001 From: "Serge E. Hallyn" Date: Fri, 26 Sep 2008 22:27:47 -0400 Subject: [PATCH 14/16] file capabilities: uninline cap_safe_nice This reduces the kernel size by 289 bytes. Signed-off-by: Serge E. Hallyn Acked-by: Andrew G. Morgan Signed-off-by: James Morris --- security/commoncap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/security/commoncap.c b/security/commoncap.c index e4c4b3fc0c04..399bfdb9e2da 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -541,7 +541,7 @@ int cap_task_post_setuid (uid_t old_ruid, uid_t old_euid, uid_t old_suid, * yet with increased caps. * So we check for increased caps on the target process. */ -static inline int cap_safe_nice(struct task_struct *p) +static int cap_safe_nice(struct task_struct *p) { if (!cap_issubset(p->cap_permitted, current->cap_permitted) && !capable(CAP_SYS_NICE)) From ea6b184f7d521a503ecab71feca6e4057562252b Mon Sep 17 00:00:00 2001 From: Stephen Smalley Date: Mon, 22 Sep 2008 15:41:19 -0400 Subject: [PATCH 15/16] selinux: use default proc sid on symlinks As we are not concerned with fine-grained control over reading of symlinks in proc, always use the default proc SID for all proc symlinks. This should help avoid permission issues upon changes to the proc tree as in the /proc/net -> /proc/self/net example. This does not alter labeling of symlinks within /proc/pid directories. ls -Zd /proc/net output before and after the patch should show the difference. Signed-off-by: Stephen D. Smalley Signed-off-by: James Morris --- security/selinux/hooks.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 89f446d86054..4a7374c12d9c 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -1291,7 +1291,7 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent /* Default to the fs superblock SID. */ isec->sid = sbsec->sid; - if (sbsec->proc) { + if (sbsec->proc && !S_ISLNK(inode->i_mode)) { struct proc_inode *proci = PROC_I(inode); if (proci->pde) { isec->sclass = inode_mode_to_security_class(inode->i_mode); From 81990fbdd18b9cfdc93dc221ff3250f81468aed8 Mon Sep 17 00:00:00 2001 From: Paul Moore Date: Fri, 3 Oct 2008 10:51:15 -0400 Subject: [PATCH 16/16] selinux: Fix an uninitialized variable BUG/panic in selinux_secattr_to_sid() At some point during the 2.6.27 development cycle two new fields were added to the SELinux context structure, a string pointer and a length field. The code in selinux_secattr_to_sid() was not modified and as a result these two fields were left uninitialized which could result in erratic behavior, including kernel panics, when NetLabel is used. This patch fixes the problem by fully initializing the context in selinux_secattr_to_sid() before use and reducing the level of direct context manipulation done to help prevent future problems. Please apply this to the 2.6.27-rcX release stream. Signed-off-by: Paul Moore Signed-off-by: James Morris --- security/selinux/ss/services.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index 876b815c1ba4..ab0cc0c7b944 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -2907,6 +2907,7 @@ int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr, if (ctx == NULL) goto netlbl_secattr_to_sid_return; + context_init(&ctx_new); ctx_new.user = ctx->user; ctx_new.role = ctx->role; ctx_new.type = ctx->type; @@ -2915,13 +2916,9 @@ int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr, if (ebitmap_netlbl_import(&ctx_new.range.level[0].cat, secattr->attr.mls.cat) != 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); + memcpy(&ctx_new.range.level[1].cat, + &ctx_new.range.level[0].cat, + sizeof(ctx_new.range.level[0].cat)); } if (mls_context_isvalid(&policydb, &ctx_new) != 1) goto netlbl_secattr_to_sid_return_cleanup;