diff --git a/security/selinux/avc.c b/security/selinux/avc.c index a300702da5276a41a5c86a68e389f5ebcacdc058..74c0319c417e1e143bb7cd468c9744d8fabf88bb 100644 --- a/security/selinux/avc.c +++ b/security/selinux/avc.c @@ -32,12 +32,7 @@ #include "avc.h" #include "avc_ss.h" -static const struct av_perm_to_string -{ - u16 tclass; - u32 value; - const char *name; -} av_perm_to_string[] = { +static const struct av_perm_to_string av_perm_to_string[] = { #define S_(c, v, s) { c, v, s }, #include "av_perm_to_string.h" #undef S_ @@ -57,17 +52,21 @@ static const char *class_to_string[] = { #undef TE_ #undef S_ -static const struct av_inherit -{ - u16 tclass; - const char **common_pts; - u32 common_base; -} av_inherit[] = { +static const struct av_inherit av_inherit[] = { #define S_(c, i, b) { c, common_##i##_perm_to_string, b }, #include "av_inherit.h" #undef S_ }; +const struct selinux_class_perm selinux_class_perm = { + av_perm_to_string, + ARRAY_SIZE(av_perm_to_string), + class_to_string, + ARRAY_SIZE(class_to_string), + av_inherit, + ARRAY_SIZE(av_inherit) +}; + #define AVC_CACHE_SLOTS 512 #define AVC_DEF_CACHE_THRESHOLD 512 #define AVC_CACHE_RECLAIM 16 diff --git a/security/selinux/include/avc_ss.h b/security/selinux/include/avc_ss.h index 450a2831e2e32c2cf5f58f42eab831a7654dd0af..ff869e8b6f4a044852234c78b6e412000eac8153 100644 --- a/security/selinux/include/avc_ss.h +++ b/security/selinux/include/avc_ss.h @@ -10,5 +10,29 @@ int avc_ss_reset(u32 seqno); +struct av_perm_to_string +{ + u16 tclass; + u32 value; + const char *name; +}; + +struct av_inherit +{ + u16 tclass; + const char **common_pts; + u32 common_base; +}; + +struct selinux_class_perm +{ + const struct av_perm_to_string *av_perm_to_string; + u32 av_pts_len; + const char **class_to_string; + u32 cts_len; + const struct av_inherit *av_inherit; + u32 av_inherit_len; +}; + #endif /* _SELINUX_AVC_SS_H_ */ diff --git a/security/selinux/ss/hashtab.c b/security/selinux/ss/hashtab.c index 24e5ec957630a752c270d8583ac4a2b6f797d31b..77b530c3bbceee385634830d7c9f09f2f6fa8d44 100644 --- a/security/selinux/ss/hashtab.c +++ b/security/selinux/ss/hashtab.c @@ -8,8 +8,8 @@ #include #include "hashtab.h" -struct hashtab *hashtab_create(u32 (*hash_value)(struct hashtab *h, void *key), - int (*keycmp)(struct hashtab *h, void *key1, void *key2), +struct hashtab *hashtab_create(u32 (*hash_value)(struct hashtab *h, const void *key), + int (*keycmp)(struct hashtab *h, const void *key1, const void *key2), u32 size) { struct hashtab *p; @@ -71,7 +71,7 @@ int hashtab_insert(struct hashtab *h, void *key, void *datum) return 0; } -void *hashtab_search(struct hashtab *h, void *key) +void *hashtab_search(struct hashtab *h, const void *key) { u32 hvalue; struct hashtab_node *cur; diff --git a/security/selinux/ss/hashtab.h b/security/selinux/ss/hashtab.h index 4cc85816a718a25f62de9e4a5f830683fc8f509a..7e2ff3e3c6d220759c0d123f024c904dfc4b3d69 100644 --- a/security/selinux/ss/hashtab.h +++ b/security/selinux/ss/hashtab.h @@ -22,9 +22,9 @@ struct hashtab { struct hashtab_node **htable; /* hash table */ u32 size; /* number of slots in hash table */ u32 nel; /* number of elements in hash table */ - u32 (*hash_value)(struct hashtab *h, void *key); + u32 (*hash_value)(struct hashtab *h, const void *key); /* hash function */ - int (*keycmp)(struct hashtab *h, void *key1, void *key2); + int (*keycmp)(struct hashtab *h, const void *key1, const void *key2); /* key comparison function */ }; @@ -39,8 +39,8 @@ struct hashtab_info { * Returns NULL if insufficent space is available or * the new hash table otherwise. */ -struct hashtab *hashtab_create(u32 (*hash_value)(struct hashtab *h, void *key), - int (*keycmp)(struct hashtab *h, void *key1, void *key2), +struct hashtab *hashtab_create(u32 (*hash_value)(struct hashtab *h, const void *key), + int (*keycmp)(struct hashtab *h, const void *key1, const void *key2), u32 size); /* @@ -59,7 +59,7 @@ int hashtab_insert(struct hashtab *h, void *k, void *d); * Returns NULL if no entry has the specified key or * the datum of the entry otherwise. */ -void *hashtab_search(struct hashtab *h, void *k); +void *hashtab_search(struct hashtab *h, const void *k); /* * Destroys the specified hash table. diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index bfe122764c98c2638183a5d37390e63d5f62a73b..408820486af04eaa9574d5f014324d1029309fed 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -17,9 +17,13 @@ * * Added support for NetLabel * + * Updated: Chad Sellers + * + * Added validation of kernel classes and permissions + * * 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 - 2004, 2006 Tresys Technology, LLC * Copyright (C) 2003 Red Hat, Inc., James Morris * 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 @@ -53,6 +57,11 @@ extern void selnl_notify_policyload(u32 seqno); unsigned int policydb_loaded_version; +/* + * This is declared in avc.c + */ +extern const struct selinux_class_perm selinux_class_perm; + static DEFINE_RWLOCK(policy_rwlock); #define POLICY_RDLOCK read_lock(&policy_rwlock) #define POLICY_WRLOCK write_lock_irq(&policy_rwlock) @@ -1019,86 +1028,112 @@ int security_change_sid(u32 ssid, } /* - * Verify that each permission that is defined under the - * existing policy is still defined with the same value - * in the new policy. + * Verify that each kernel class that is defined in the + * policy is correct */ -static int validate_perm(void *key, void *datum, void *p) +static int validate_classes(struct policydb *p) { - struct hashtab *h; - struct perm_datum *perdatum, *perdatum2; - int rc = 0; - - - h = p; - perdatum = datum; - - perdatum2 = hashtab_search(h, key); - if (!perdatum2) { - printk(KERN_ERR "security: permission %s disappeared", - (char *)key); - rc = -ENOENT; - goto out; - } - if (perdatum->value != perdatum2->value) { - printk(KERN_ERR "security: the value of permission %s changed", - (char *)key); - rc = -EINVAL; - } -out: - return rc; -} - -/* - * Verify that each class that is defined under the - * existing policy is still defined with the same - * attributes in the new policy. - */ -static int validate_class(void *key, void *datum, void *p) -{ - struct policydb *newp; - struct class_datum *cladatum, *cladatum2; - int rc; - - newp = p; - cladatum = datum; - - cladatum2 = hashtab_search(newp->p_classes.table, key); - if (!cladatum2) { - printk(KERN_ERR "security: class %s disappeared\n", - (char *)key); - rc = -ENOENT; - goto out; - } - if (cladatum->value != cladatum2->value) { - printk(KERN_ERR "security: the value of class %s changed\n", - (char *)key); - rc = -EINVAL; - goto out; + int i, j; + struct class_datum *cladatum; + struct perm_datum *perdatum; + u32 nprim, tmp, common_pts_len, perm_val, pol_val; + u16 class_val; + const struct selinux_class_perm *kdefs = &selinux_class_perm; + const char *def_class, *def_perm, *pol_class; + struct symtab *perms; + + for (i = 1; i < kdefs->cts_len; i++) { + def_class = kdefs->class_to_string[i]; + if (i > p->p_classes.nprim) { + printk(KERN_INFO + "security: class %s not defined in policy\n", + def_class); + continue; + } + pol_class = p->p_class_val_to_name[i-1]; + if (strcmp(pol_class, def_class)) { + printk(KERN_ERR + "security: class %d is incorrect, found %s but should be %s\n", + i, pol_class, def_class); + return -EINVAL; + } } - if ((cladatum->comdatum && !cladatum2->comdatum) || - (!cladatum->comdatum && cladatum2->comdatum)) { - printk(KERN_ERR "security: the inherits clause for the access " - "vector definition for class %s changed\n", (char *)key); - rc = -EINVAL; - goto out; + for (i = 0; i < kdefs->av_pts_len; i++) { + class_val = kdefs->av_perm_to_string[i].tclass; + perm_val = kdefs->av_perm_to_string[i].value; + def_perm = kdefs->av_perm_to_string[i].name; + if (class_val > p->p_classes.nprim) + continue; + pol_class = p->p_class_val_to_name[class_val-1]; + cladatum = hashtab_search(p->p_classes.table, pol_class); + BUG_ON(!cladatum); + perms = &cladatum->permissions; + nprim = 1 << (perms->nprim - 1); + if (perm_val > nprim) { + printk(KERN_INFO + "security: permission %s in class %s not defined in policy\n", + def_perm, pol_class); + continue; + } + perdatum = hashtab_search(perms->table, def_perm); + if (perdatum == NULL) { + printk(KERN_ERR + "security: permission %s in class %s not found in policy\n", + def_perm, pol_class); + return -EINVAL; + } + pol_val = 1 << (perdatum->value - 1); + if (pol_val != perm_val) { + printk(KERN_ERR + "security: permission %s in class %s has incorrect value\n", + def_perm, pol_class); + return -EINVAL; + } } - if (cladatum->comdatum) { - rc = hashtab_map(cladatum->comdatum->permissions.table, validate_perm, - cladatum2->comdatum->permissions.table); - if (rc) { - printk(" in the access vector definition for class " - "%s\n", (char *)key); - goto out; + for (i = 0; i < kdefs->av_inherit_len; i++) { + class_val = kdefs->av_inherit[i].tclass; + if (class_val > p->p_classes.nprim) + continue; + pol_class = p->p_class_val_to_name[class_val-1]; + cladatum = hashtab_search(p->p_classes.table, pol_class); + BUG_ON(!cladatum); + if (!cladatum->comdatum) { + printk(KERN_ERR + "security: class %s should have an inherits clause but does not\n", + pol_class); + return -EINVAL; + } + tmp = kdefs->av_inherit[i].common_base; + common_pts_len = 0; + while (!(tmp & 0x01)) { + common_pts_len++; + tmp >>= 1; + } + perms = &cladatum->comdatum->permissions; + for (j = 0; j < common_pts_len; j++) { + def_perm = kdefs->av_inherit[i].common_pts[j]; + if (j >= perms->nprim) { + printk(KERN_INFO + "security: permission %s in class %s not defined in policy\n", + def_perm, pol_class); + continue; + } + perdatum = hashtab_search(perms->table, def_perm); + if (perdatum == NULL) { + printk(KERN_ERR + "security: permission %s in class %s not found in policy\n", + def_perm, pol_class); + return -EINVAL; + } + if (perdatum->value != j + 1) { + printk(KERN_ERR + "security: permission %s in class %s has incorrect value\n", + def_perm, pol_class); + return -EINVAL; + } } } - rc = hashtab_map(cladatum->permissions.table, validate_perm, - cladatum2->permissions.table); - if (rc) - printk(" in access vector definition for class %s\n", - (char *)key); -out: - return rc; + return 0; } /* Clone the SID into the new SID table. */ @@ -1243,6 +1278,16 @@ int security_load_policy(void *data, size_t len) avtab_cache_destroy(); return -EINVAL; } + /* Verify that the kernel defined classes are correct. */ + if (validate_classes(&policydb)) { + printk(KERN_ERR + "security: the definition of a class is incorrect\n"); + LOAD_UNLOCK; + sidtab_destroy(&sidtab); + policydb_destroy(&policydb); + avtab_cache_destroy(); + return -EINVAL; + } policydb_loaded_version = policydb.policyvers; ss_initialized = 1; seqno = ++latest_granting; @@ -1265,10 +1310,10 @@ int security_load_policy(void *data, size_t len) sidtab_init(&newsidtab); - /* Verify that the existing classes did not change. */ - if (hashtab_map(policydb.p_classes.table, validate_class, &newpolicydb)) { - printk(KERN_ERR "security: the definition of an existing " - "class changed\n"); + /* Verify that the kernel defined classes are correct. */ + if (validate_classes(&newpolicydb)) { + printk(KERN_ERR + "security: the definition of a class is incorrect\n"); rc = -EINVAL; goto err; } diff --git a/security/selinux/ss/symtab.c b/security/selinux/ss/symtab.c index 24a10d36d3b664a939f2febfed902c072310e497..837658a98a5418080d9e7264c450e780ee939b7c 100644 --- a/security/selinux/ss/symtab.c +++ b/security/selinux/ss/symtab.c @@ -9,9 +9,9 @@ #include #include "symtab.h" -static unsigned int symhash(struct hashtab *h, void *key) +static unsigned int symhash(struct hashtab *h, const void *key) { - char *p, *keyp; + const char *p, *keyp; unsigned int size; unsigned int val; @@ -23,9 +23,9 @@ static unsigned int symhash(struct hashtab *h, void *key) return val & (h->size - 1); } -static int symcmp(struct hashtab *h, void *key1, void *key2) +static int symcmp(struct hashtab *h, const void *key1, const void *key2) { - char *keyp1, *keyp2; + const char *keyp1, *keyp2; keyp1 = key1; keyp2 = key2;