diff options
Diffstat (limited to 'security/selinux/ss/mls.c')
| -rw-r--r-- | security/selinux/ss/mls.c | 381 |
1 files changed, 174 insertions, 207 deletions
diff --git a/security/selinux/ss/mls.c b/security/selinux/ss/mls.c index 40de8d3f208e..a6e49269f535 100644 --- a/security/selinux/ss/mls.c +++ b/security/selinux/ss/mls.c @@ -1,21 +1,18 @@ +// SPDX-License-Identifier: GPL-2.0 /* * Implementation of the multi-level security (MLS) policy. * - * Author : Stephen Smalley, <sds@epoch.ncsc.mil> + * Author : Stephen Smalley, <stephen.smalley.work@gmail.com> */ + /* * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com> + * Support for enhanced MLS infrastructure. + * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc. * - * Support for enhanced MLS infrastructure. - * - * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc. - */ -/* * Updated: Hewlett-Packard <paul@paul-moore.com> - * - * Added support to import/export the MLS label from NetLabel - * - * (c) Copyright Hewlett-Packard Development Company, L.P., 2006 + * Added support to import/export the MLS label from NetLabel + * Copyright (C) Hewlett-Packard Development Company, L.P., 2006 */ #include <linux/kernel.h> @@ -32,40 +29,41 @@ * Return the length in bytes for the MLS fields of the * security context string representation of `context'. */ -int mls_compute_context_len(struct context *context) +int mls_compute_context_len(struct policydb *p, struct context *context) { int i, l, len, head, prev; char *nm; struct ebitmap *e; struct ebitmap_node *node; - if (!policydb.mls_enabled) + if (!p->mls_enabled) return 0; len = 1; /* for the beginning ":" */ for (l = 0; l < 2; l++) { - int index_sens = context->range.level[l].sens; - len += strlen(sym_name(&policydb, SYM_LEVELS, index_sens - 1)); + u32 index_sens = context->range.level[l].sens; + len += strlen(sym_name(p, SYM_LEVELS, index_sens - 1)); /* categories */ head = -2; prev = -2; e = &context->range.level[l].cat; - ebitmap_for_each_positive_bit(e, node, i) { + ebitmap_for_each_positive_bit(e, node, i) + { if (i - prev > 1) { /* one or more negative bits are skipped */ if (head != prev) { - nm = sym_name(&policydb, SYM_CATS, prev); + nm = sym_name(p, SYM_CATS, prev); len += strlen(nm) + 1; } - nm = sym_name(&policydb, SYM_CATS, i); + nm = sym_name(p, SYM_CATS, i); len += strlen(nm) + 1; head = i; } prev = i; } if (prev != head) { - nm = sym_name(&policydb, SYM_CATS, prev); + nm = sym_name(p, SYM_CATS, prev); len += strlen(nm) + 1; } if (l == 0) { @@ -85,7 +83,7 @@ int mls_compute_context_len(struct context *context) * the MLS fields of `context' into the string `*scontext'. * Update `*scontext' to point to the end of the MLS fields. */ -void mls_sid_to_context(struct context *context, +void mls_sid_to_context(struct policydb *p, struct context *context, char **scontext) { char *scontextp, *nm; @@ -93,7 +91,7 @@ void mls_sid_to_context(struct context *context, struct ebitmap *e; struct ebitmap_node *node; - if (!policydb.mls_enabled) + if (!p->mls_enabled) return; scontextp = *scontext; @@ -102,7 +100,7 @@ void mls_sid_to_context(struct context *context, scontextp++; for (l = 0; l < 2; l++) { - strcpy(scontextp, sym_name(&policydb, SYM_LEVELS, + strcpy(scontextp, sym_name(p, SYM_LEVELS, context->range.level[l].sens - 1)); scontextp += strlen(scontextp); @@ -110,7 +108,8 @@ void mls_sid_to_context(struct context *context, head = -2; prev = -2; e = &context->range.level[l].cat; - ebitmap_for_each_positive_bit(e, node, i) { + ebitmap_for_each_positive_bit(e, node, i) + { if (i - prev > 1) { /* one or more negative bits are skipped */ if (prev != head) { @@ -118,7 +117,7 @@ void mls_sid_to_context(struct context *context, *scontextp++ = '.'; else *scontextp++ = ','; - nm = sym_name(&policydb, SYM_CATS, prev); + nm = sym_name(p, SYM_CATS, prev); strcpy(scontextp, nm); scontextp += strlen(nm); } @@ -126,7 +125,7 @@ void mls_sid_to_context(struct context *context, *scontextp++ = ':'; else *scontextp++ = ','; - nm = sym_name(&policydb, SYM_CATS, i); + nm = sym_name(p, SYM_CATS, i); strcpy(scontextp, nm); scontextp += strlen(nm); head = i; @@ -139,7 +138,7 @@ void mls_sid_to_context(struct context *context, *scontextp++ = '.'; else *scontextp++ = ','; - nm = sym_name(&policydb, SYM_CATS, prev); + nm = sym_name(p, SYM_CATS, prev); strcpy(scontextp, nm); scontextp += strlen(nm); } @@ -154,35 +153,26 @@ void mls_sid_to_context(struct context *context, } *scontext = scontextp; - return; } int mls_level_isvalid(struct policydb *p, struct mls_level *l) { struct level_datum *levdatum; - struct ebitmap_node *node; - int i; if (!l->sens || l->sens > p->p_levels.nprim) return 0; - levdatum = hashtab_search(p->p_levels.table, - sym_name(p, SYM_LEVELS, l->sens - 1)); + levdatum = symtab_search(&p->p_levels, + sym_name(p, SYM_LEVELS, l->sens - 1)); if (!levdatum) return 0; - ebitmap_for_each_positive_bit(&l->cat, node, i) { - if (i > p->p_cats.nprim) - return 0; - if (!ebitmap_get_bit(&levdatum->level->cat, i)) { - /* - * Category may not be associated with - * sensitivity. - */ - return 0; - } - } - - return 1; + /* + * Return 1 iff all the bits set in l->cat are also be set in + * levdatum->level->cat and no bit in l->cat is larger than + * p->p_cats.nprim. + */ + return ebitmap_contains(&levdatum->level.cat, &l->cat, + p->p_cats.nprim); } int mls_range_isvalid(struct policydb *p, struct mls_range *r) @@ -224,9 +214,7 @@ int mls_context_isvalid(struct policydb *p, struct context *c) /* * Set the MLS fields in the security context structure * `context' based on the string representation in - * the string `*scontext'. Update `*scontext' to - * point to the end of the string representation of - * the MLS fields. + * the string `scontext'. * * This function modifies the string in place, inserting * NULL characters to terminate the MLS fields. @@ -239,23 +227,23 @@ int mls_context_isvalid(struct policydb *p, struct context *c) * Policy read-lock must be held for sidtab lookup. * */ -int mls_context_to_sid(struct policydb *pol, - char oldc, - char **scontext, - struct context *context, - struct sidtab *s, - u32 def_sid) +int mls_context_to_sid(struct policydb *pol, char oldc, char *scontext, + struct context *context, struct sidtab *s, u32 def_sid) { - - char delim; - char *scontextp, *p, *rngptr; + char *sensitivity, *cur_cat, *next_cat, *rngptr; struct level_datum *levdatum; struct cat_datum *catdatum, *rngdatum; - int l, rc = -EINVAL; + u32 i; + int l, rc; + char *rangep[2]; if (!pol->mls_enabled) { - if (def_sid != SECSID_NULL && oldc) - *scontext += strlen(*scontext) + 1; + /* + * With no MLS, only return -EINVAL if there is a MLS field + * and it did not come from an xattr. + */ + if (oldc && def_sid == SECSID_NULL) + return -EINVAL; return 0; } @@ -267,113 +255,95 @@ int mls_context_to_sid(struct policydb *pol, struct context *defcon; if (def_sid == SECSID_NULL) - goto out; + return -EINVAL; defcon = sidtab_search(s, def_sid); if (!defcon) - goto out; + return -EINVAL; - rc = mls_context_cpy(context, defcon); - goto out; + return mls_context_cpy(context, defcon); } - /* Extract low sensitivity. */ - scontextp = p = *scontext; - while (*p && *p != ':' && *p != '-') - p++; - - delim = *p; - if (delim != '\0') - *p++ = '\0'; + /* + * If we're dealing with a range, figure out where the two parts + * of the range begin. + */ + rangep[0] = scontext; + rangep[1] = strchr(scontext, '-'); + if (rangep[1]) { + rangep[1][0] = '\0'; + rangep[1]++; + } + /* For each part of the range: */ for (l = 0; l < 2; l++) { - levdatum = hashtab_search(pol->p_levels.table, scontextp); - if (!levdatum) { - rc = -EINVAL; - goto out; - } + /* Split sensitivity and category set. */ + sensitivity = rangep[l]; + if (sensitivity == NULL) + break; + next_cat = strchr(sensitivity, ':'); + if (next_cat) + *(next_cat++) = '\0'; - context->range.level[l].sens = levdatum->level->sens; - - if (delim == ':') { - /* Extract category set. */ - while (1) { - scontextp = p; - while (*p && *p != ',' && *p != '-') - p++; - delim = *p; - if (delim != '\0') - *p++ = '\0'; - - /* Separate into range if exists */ - rngptr = strchr(scontextp, '.'); - if (rngptr != NULL) { - /* Remove '.' */ - *rngptr++ = '\0'; - } + /* Parse sensitivity. */ + levdatum = symtab_search(&pol->p_levels, sensitivity); + if (!levdatum) + return -EINVAL; + context->range.level[l].sens = levdatum->level.sens; + + /* Extract category set. */ + while (next_cat != NULL) { + cur_cat = next_cat; + next_cat = strchr(next_cat, ','); + if (next_cat != NULL) + *(next_cat++) = '\0'; + + /* Separate into range if exists */ + rngptr = strchr(cur_cat, '.'); + if (rngptr != NULL) { + /* Remove '.' */ + *rngptr++ = '\0'; + } - catdatum = hashtab_search(pol->p_cats.table, - scontextp); - if (!catdatum) { - rc = -EINVAL; - goto out; - } + catdatum = symtab_search(&pol->p_cats, cur_cat); + if (!catdatum) + return -EINVAL; - rc = ebitmap_set_bit(&context->range.level[l].cat, - catdatum->value - 1, 1); - if (rc) - goto out; - - /* If range, set all categories in range */ - if (rngptr) { - int i; - - rngdatum = hashtab_search(pol->p_cats.table, rngptr); - if (!rngdatum) { - rc = -EINVAL; - goto out; - } - - if (catdatum->value >= rngdatum->value) { - rc = -EINVAL; - goto out; - } - - for (i = catdatum->value; i < rngdatum->value; i++) { - rc = ebitmap_set_bit(&context->range.level[l].cat, i, 1); - if (rc) - goto out; - } - } + rc = ebitmap_set_bit(&context->range.level[l].cat, + catdatum->value - 1, 1); + if (rc) + return rc; + + /* If range, set all categories in range */ + if (rngptr == NULL) + continue; + + rngdatum = symtab_search(&pol->p_cats, rngptr); + if (!rngdatum) + return -EINVAL; - if (delim != ',') - break; + if (catdatum->value >= rngdatum->value) + return -EINVAL; + + for (i = catdatum->value; i < rngdatum->value; i++) { + rc = ebitmap_set_bit( + &context->range.level[l].cat, i, 1); + if (rc) + return rc; } } - if (delim == '-') { - /* Extract high sensitivity. */ - scontextp = p; - while (*p && *p != ':') - p++; - - delim = *p; - if (delim != '\0') - *p++ = '\0'; - } else - break; } - if (l == 0) { + /* If we didn't see a '-', the range start is also the range end. */ + if (rangep[1] == NULL) { context->range.level[1].sens = context->range.level[0].sens; rc = ebitmap_cpy(&context->range.level[1].cat, &context->range.level[0].cat); if (rc) - goto out; + return rc; } - *scontext = ++p; - rc = 0; -out: - return rc; + + return 0; } /* @@ -382,23 +352,22 @@ out: * the string `str'. This function will allocate temporary memory with the * given constraints of gfp_mask. */ -int mls_from_string(char *str, struct context *context, gfp_t gfp_mask) +int mls_from_string(struct policydb *p, char *str, struct context *context, + gfp_t gfp_mask) { - char *tmpstr, *freestr; + char *tmpstr; int rc; - if (!policydb.mls_enabled) + if (!p->mls_enabled) return -EINVAL; - /* we need freestr because mls_context_to_sid will change - the value of tmpstr */ - tmpstr = freestr = kstrdup(str, gfp_mask); + tmpstr = kstrdup(str, gfp_mask); if (!tmpstr) { rc = -ENOMEM; } else { - rc = mls_context_to_sid(&policydb, ':', &tmpstr, context, - NULL, SECSID_NULL); - kfree(freestr); + rc = mls_context_to_sid(p, ':', tmpstr, context, NULL, + SECSID_NULL); + kfree(tmpstr); } return rc; @@ -407,8 +376,7 @@ int mls_from_string(char *str, struct context *context, gfp_t gfp_mask) /* * Copies the MLS range `range' into `context'. */ -int mls_range_set(struct context *context, - struct mls_range *range) +int mls_range_set(struct context *context, struct mls_range *range) { int l, rc = 0; @@ -424,10 +392,10 @@ int mls_range_set(struct context *context, return rc; } -int mls_setup_user_range(struct context *fromcon, struct user_datum *user, - struct context *usercon) +int mls_setup_user_range(struct policydb *p, struct context *fromcon, + struct user_datum *user, struct context *usercon) { - if (policydb.mls_enabled) { + if (p->mls_enabled) { struct mls_level *fromcon_sen = &(fromcon->range.level[0]); struct mls_level *fromcon_clr = &(fromcon->range.level[1]); struct mls_level *user_low = &(user->range.level[0]); @@ -464,63 +432,61 @@ int mls_setup_user_range(struct context *fromcon, struct user_datum *user, /* * Convert the MLS fields in the security context - * structure `c' from the values specified in the - * policy `oldp' to the values specified in the policy `newp'. + * structure `oldc' from the values specified in the + * policy `oldp' to the values specified in the policy `newp', + * storing the resulting context in `newc'. */ -int mls_convert_context(struct policydb *oldp, - struct policydb *newp, - struct context *c) +int mls_convert_context(struct policydb *oldp, struct policydb *newp, + struct context *oldc, struct context *newc) { struct level_datum *levdatum; struct cat_datum *catdatum; - struct ebitmap bitmap; struct ebitmap_node *node; - int l, i; + u32 i; + int l; - if (!policydb.mls_enabled) + if (!oldp->mls_enabled || !newp->mls_enabled) return 0; for (l = 0; l < 2; l++) { - levdatum = hashtab_search(newp->p_levels.table, - sym_name(oldp, SYM_LEVELS, - c->range.level[l].sens - 1)); + char *name = sym_name(oldp, SYM_LEVELS, + oldc->range.level[l].sens - 1); + + levdatum = symtab_search(&newp->p_levels, name); if (!levdatum) return -EINVAL; - c->range.level[l].sens = levdatum->level->sens; + newc->range.level[l].sens = levdatum->level.sens; - ebitmap_init(&bitmap); - ebitmap_for_each_positive_bit(&c->range.level[l].cat, node, i) { + ebitmap_for_each_positive_bit(&oldc->range.level[l].cat, node, + i) + { int rc; - catdatum = hashtab_search(newp->p_cats.table, - sym_name(oldp, SYM_CATS, i)); + catdatum = symtab_search(&newp->p_cats, + sym_name(oldp, SYM_CATS, i)); if (!catdatum) return -EINVAL; - rc = ebitmap_set_bit(&bitmap, catdatum->value - 1, 1); + rc = ebitmap_set_bit(&newc->range.level[l].cat, + catdatum->value - 1, 1); if (rc) return rc; } - ebitmap_destroy(&c->range.level[l].cat); - c->range.level[l].cat = bitmap; } return 0; } -int mls_compute_sid(struct context *scontext, - struct context *tcontext, - u16 tclass, - u32 specified, - struct context *newcontext, - bool sock) +int mls_compute_sid(struct policydb *p, struct context *scontext, + struct context *tcontext, u16 tclass, u32 specified, + struct context *newcontext, bool sock) { struct range_trans rtr; struct mls_range *r; struct class_datum *cladatum; - int default_range = 0; + char default_range = 0; - if (!policydb.mls_enabled) + if (!p->mls_enabled) return 0; switch (specified) { @@ -529,12 +495,12 @@ int mls_compute_sid(struct context *scontext, rtr.source_type = scontext->type; rtr.target_type = tcontext->type; rtr.target_class = tclass; - r = hashtab_search(policydb.range_tr, &rtr); + r = policydb_rangetr_search(p, &rtr); if (r) return mls_range_set(newcontext, r); - if (tclass && tclass <= policydb.p_classes.nprim) { - cladatum = policydb.class_val_to_struct[tclass - 1]; + if (tclass && tclass <= p->p_classes.nprim) { + cladatum = p->class_val_to_struct[tclass - 1]; if (cladatum) default_range = cladatum->default_range; } @@ -552,11 +518,14 @@ int mls_compute_sid(struct context *scontext, return mls_context_cpy_high(newcontext, tcontext); case DEFAULT_TARGET_LOW_HIGH: return mls_context_cpy(newcontext, tcontext); + case DEFAULT_GLBLUB: + return mls_context_glblub(newcontext, scontext, + tcontext); } - /* Fallthrough */ + fallthrough; case AVTAB_CHANGE: - if ((tclass == policydb.process_class) || (sock == true)) + if ((tclass == p->process_class) || sock) /* Use the process MLS attributes. */ return mls_context_cpy(newcontext, scontext); else @@ -565,8 +534,6 @@ int mls_compute_sid(struct context *scontext, case AVTAB_MEMBER: /* Use the process effective MLS attributes. */ return mls_context_cpy_low(newcontext, scontext); - - /* fall through */ } return -EINVAL; } @@ -574,6 +541,7 @@ int mls_compute_sid(struct context *scontext, #ifdef CONFIG_NETLABEL /** * mls_export_netlbl_lvl - Export the MLS sensitivity levels to NetLabel + * @p: the policy * @context: the security context * @secattr: the NetLabel security attributes * @@ -582,10 +550,10 @@ int mls_compute_sid(struct context *scontext, * NetLabel MLS sensitivity level field. * */ -void mls_export_netlbl_lvl(struct context *context, +void mls_export_netlbl_lvl(struct policydb *p, struct context *context, struct netlbl_lsm_secattr *secattr) { - if (!policydb.mls_enabled) + if (!p->mls_enabled) return; secattr->attr.mls.lvl = context->range.level[0].sens - 1; @@ -594,6 +562,7 @@ void mls_export_netlbl_lvl(struct context *context, /** * mls_import_netlbl_lvl - Import the NetLabel MLS sensitivity levels + * @p: the policy * @context: the security context * @secattr: the NetLabel security attributes * @@ -602,10 +571,10 @@ void mls_export_netlbl_lvl(struct context *context, * NetLabel MLS sensitivity level into the context. * */ -void mls_import_netlbl_lvl(struct context *context, +void mls_import_netlbl_lvl(struct policydb *p, struct context *context, struct netlbl_lsm_secattr *secattr) { - if (!policydb.mls_enabled) + if (!p->mls_enabled) return; context->range.level[0].sens = secattr->attr.mls.lvl + 1; @@ -614,6 +583,7 @@ void mls_import_netlbl_lvl(struct context *context, /** * mls_export_netlbl_cat - Export the MLS categories to NetLabel + * @p: the policy * @context: the security context * @secattr: the NetLabel security attributes * @@ -622,12 +592,12 @@ void mls_import_netlbl_lvl(struct context *context, * MLS category field. Returns zero on success, negative values on failure. * */ -int mls_export_netlbl_cat(struct context *context, +int mls_export_netlbl_cat(struct policydb *p, struct context *context, struct netlbl_lsm_secattr *secattr) { int rc; - if (!policydb.mls_enabled) + if (!p->mls_enabled) return 0; rc = ebitmap_netlbl_export(&context->range.level[0].cat, @@ -640,6 +610,7 @@ int mls_export_netlbl_cat(struct context *context, /** * mls_import_netlbl_cat - Import the MLS categories from NetLabel + * @p: the policy * @context: the security context * @secattr: the NetLabel security attributes * @@ -650,29 +621,25 @@ int mls_export_netlbl_cat(struct context *context, * negative values on failure. * */ -int mls_import_netlbl_cat(struct context *context, +int mls_import_netlbl_cat(struct policydb *p, struct context *context, struct netlbl_lsm_secattr *secattr) { int rc; - if (!policydb.mls_enabled) + if (!p->mls_enabled) return 0; rc = ebitmap_netlbl_import(&context->range.level[0].cat, secattr->attr.mls.cat); - if (rc != 0) - goto import_netlbl_cat_failure; - - rc = ebitmap_cpy(&context->range.level[1].cat, - &context->range.level[0].cat); - if (rc != 0) + if (rc) goto import_netlbl_cat_failure; + memcpy(&context->range.level[1].cat, &context->range.level[0].cat, + sizeof(context->range.level[0].cat)); return 0; import_netlbl_cat_failure: ebitmap_destroy(&context->range.level[0].cat); - ebitmap_destroy(&context->range.level[1].cat); return rc; } #endif /* CONFIG_NETLABEL */ |
