diff options
| -rw-r--r-- | Documentation/ABI/testing/ima_policy | 8 | ||||
| -rw-r--r-- | security/integrity/ima/ima_policy.c | 201 |
2 files changed, 180 insertions, 29 deletions
diff --git a/Documentation/ABI/testing/ima_policy b/Documentation/ABI/testing/ima_policy index 5c2798534950..e1a04bd3b9e5 100644 --- a/Documentation/ABI/testing/ima_policy +++ b/Documentation/ABI/testing/ima_policy @@ -22,8 +22,9 @@ Description: action: measure | dont_measure | appraise | dont_appraise | audit | hash | dont_hash condition:= base | lsm [option] - base: [[func=] [mask=] [fsmagic=] [fsuuid=] [uid=] - [euid=] [fowner=] [fsname=]] + base: [[func=] [mask=] [fsmagic=] [fsuuid=] [fsname=] + [uid=] [euid=] [gid=] [egid=] + [fowner=] [fgroup=]] lsm: [[subj_user=] [subj_role=] [subj_type=] [obj_user=] [obj_role=] [obj_type=]] option: [[appraise_type=]] [template=] [permit_directio] @@ -40,7 +41,10 @@ Description: fsuuid:= file system UUID (e.g 8bcbe394-4f13-4144-be8e-5aa9ea2ce2f6) uid:= decimal value euid:= decimal value + gid:= decimal value + egid:= decimal value fowner:= decimal value + fgroup:= decimal value lsm: are LSM specific option: appraise_type:= [imasig] [imasig|modsig] diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index 013a423d14b6..789e6db3959f 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -36,6 +36,9 @@ #define IMA_KEYRINGS 0x0400 #define IMA_LABEL 0x0800 #define IMA_VALIDATE_ALGOS 0x1000 +#define IMA_GID 0x2000 +#define IMA_EGID 0x4000 +#define IMA_FGROUP 0x8000 #define UNKNOWN 0 #define MEASURE 0x0001 /* same as IMA_MEASURE */ @@ -78,9 +81,13 @@ struct ima_rule_entry { unsigned long fsmagic; uuid_t fsuuid; kuid_t uid; + kgid_t gid; kuid_t fowner; + kgid_t fgroup; bool (*uid_op)(kuid_t cred_uid, kuid_t rule_uid); /* Handlers for operators */ + bool (*gid_op)(kgid_t cred_gid, kgid_t rule_gid); bool (*fowner_op)(kuid_t cred_uid, kuid_t rule_uid); /* uid_eq(), uid_gt(), uid_lt() */ + bool (*fgroup_op)(kgid_t cred_gid, kgid_t rule_gid); /* gid_eq(), gid_gt(), gid_lt() */ int pcr; unsigned int allowed_algos; /* bitfield of allowed hash algorithms */ struct { @@ -104,7 +111,8 @@ static_assert( /* * Without LSM specific knowledge, the default policy can only be - * written in terms of .action, .func, .mask, .fsmagic, .uid, and .fowner + * written in terms of .action, .func, .mask, .fsmagic, .uid, .gid, + * .fowner, and .fgroup */ /* @@ -582,10 +590,23 @@ static bool ima_match_rules(struct ima_rule_entry *rule, } else if (!rule->uid_op(cred->euid, rule->uid)) return false; } - + if ((rule->flags & IMA_GID) && !rule->gid_op(cred->gid, rule->gid)) + return false; + if (rule->flags & IMA_EGID) { + if (has_capability_noaudit(current, CAP_SETGID)) { + if (!rule->gid_op(cred->egid, rule->gid) + && !rule->gid_op(cred->sgid, rule->gid) + && !rule->gid_op(cred->gid, rule->gid)) + return false; + } else if (!rule->gid_op(cred->egid, rule->gid)) + return false; + } if ((rule->flags & IMA_FOWNER) && !rule->fowner_op(i_uid_into_mnt(mnt_userns, inode), rule->fowner)) return false; + if ((rule->flags & IMA_FGROUP) && + !rule->fgroup_op(i_gid_into_mnt(mnt_userns, inode), rule->fgroup)) + return false; for (i = 0; i < MAX_LSM_RULES; i++) { int rc = 0; u32 osid; @@ -991,16 +1012,19 @@ void ima_update_policy(void) } /* Keep the enumeration in sync with the policy_tokens! */ -enum { +enum policy_opt { Opt_measure, Opt_dont_measure, Opt_appraise, Opt_dont_appraise, Opt_audit, Opt_hash, Opt_dont_hash, Opt_obj_user, Opt_obj_role, Opt_obj_type, Opt_subj_user, Opt_subj_role, Opt_subj_type, - Opt_func, Opt_mask, Opt_fsmagic, Opt_fsname, - Opt_fsuuid, Opt_uid_eq, Opt_euid_eq, Opt_fowner_eq, - Opt_uid_gt, Opt_euid_gt, Opt_fowner_gt, - Opt_uid_lt, Opt_euid_lt, Opt_fowner_lt, + Opt_func, Opt_mask, Opt_fsmagic, Opt_fsname, Opt_fsuuid, + Opt_uid_eq, Opt_euid_eq, Opt_gid_eq, Opt_egid_eq, + Opt_fowner_eq, Opt_fgroup_eq, + Opt_uid_gt, Opt_euid_gt, Opt_gid_gt, Opt_egid_gt, + Opt_fowner_gt, Opt_fgroup_gt, + Opt_uid_lt, Opt_euid_lt, Opt_gid_lt, Opt_egid_lt, + Opt_fowner_lt, Opt_fgroup_lt, Opt_appraise_type, Opt_appraise_flag, Opt_appraise_algos, Opt_permit_directio, Opt_pcr, Opt_template, Opt_keyrings, Opt_label, Opt_err @@ -1027,13 +1051,22 @@ static const match_table_t policy_tokens = { {Opt_fsuuid, "fsuuid=%s"}, {Opt_uid_eq, "uid=%s"}, {Opt_euid_eq, "euid=%s"}, + {Opt_gid_eq, "gid=%s"}, + {Opt_egid_eq, "egid=%s"}, {Opt_fowner_eq, "fowner=%s"}, + {Opt_fgroup_eq, "fgroup=%s"}, {Opt_uid_gt, "uid>%s"}, {Opt_euid_gt, "euid>%s"}, + {Opt_gid_gt, "gid>%s"}, + {Opt_egid_gt, "egid>%s"}, {Opt_fowner_gt, "fowner>%s"}, + {Opt_fgroup_gt, "fgroup>%s"}, {Opt_uid_lt, "uid<%s"}, {Opt_euid_lt, "euid<%s"}, + {Opt_gid_lt, "gid<%s"}, + {Opt_egid_lt, "egid<%s"}, {Opt_fowner_lt, "fowner<%s"}, + {Opt_fgroup_lt, "fgroup<%s"}, {Opt_appraise_type, "appraise_type=%s"}, {Opt_appraise_flag, "appraise_flag=%s"}, {Opt_appraise_algos, "appraise_algos=%s"}, @@ -1077,22 +1110,36 @@ static int ima_lsm_rule_init(struct ima_rule_entry *entry, } static void ima_log_string_op(struct audit_buffer *ab, char *key, char *value, - bool (*rule_operator)(kuid_t, kuid_t)) + enum policy_opt rule_operator) { if (!ab) return; - if (rule_operator == &uid_gt) + switch (rule_operator) { + case Opt_uid_gt: + case Opt_euid_gt: + case Opt_gid_gt: + case Opt_egid_gt: + case Opt_fowner_gt: + case Opt_fgroup_gt: audit_log_format(ab, "%s>", key); - else if (rule_operator == &uid_lt) + break; + case Opt_uid_lt: + case Opt_euid_lt: + case Opt_gid_lt: + case Opt_egid_lt: + case Opt_fowner_lt: + case Opt_fgroup_lt: audit_log_format(ab, "%s<", key); - else + break; + default: audit_log_format(ab, "%s=", key); + } audit_log_format(ab, "%s ", value); } static void ima_log_string(struct audit_buffer *ab, char *key, char *value) { - ima_log_string_op(ab, key, value, NULL); + ima_log_string_op(ab, key, value, Opt_err); } /* @@ -1167,7 +1214,8 @@ static bool ima_validate_rule(struct ima_rule_entry *entry) if (entry->flags & ~(IMA_FUNC | IMA_MASK | IMA_FSMAGIC | IMA_UID | IMA_FOWNER | IMA_FSUUID | IMA_INMASK | IMA_EUID | IMA_PCR | - IMA_FSNAME | IMA_DIGSIG_REQUIRED | + IMA_FSNAME | IMA_GID | IMA_EGID | + IMA_FGROUP | IMA_DIGSIG_REQUIRED | IMA_PERMIT_DIRECTIO | IMA_VALIDATE_ALGOS)) return false; @@ -1178,7 +1226,8 @@ static bool ima_validate_rule(struct ima_rule_entry *entry) if (entry->flags & ~(IMA_FUNC | IMA_MASK | IMA_FSMAGIC | IMA_UID | IMA_FOWNER | IMA_FSUUID | IMA_INMASK | IMA_EUID | IMA_PCR | - IMA_FSNAME | IMA_DIGSIG_REQUIRED | + IMA_FSNAME | IMA_GID | IMA_EGID | + IMA_FGROUP | IMA_DIGSIG_REQUIRED | IMA_PERMIT_DIRECTIO | IMA_MODSIG_ALLOWED | IMA_CHECK_BLACKLIST | IMA_VALIDATE_ALGOS)) return false; @@ -1190,7 +1239,8 @@ static bool ima_validate_rule(struct ima_rule_entry *entry) if (entry->flags & ~(IMA_FUNC | IMA_FSMAGIC | IMA_UID | IMA_FOWNER | IMA_FSUUID | IMA_EUID | - IMA_PCR | IMA_FSNAME)) + IMA_PCR | IMA_FSNAME | IMA_GID | IMA_EGID | + IMA_FGROUP)) return false; break; @@ -1198,7 +1248,7 @@ static bool ima_validate_rule(struct ima_rule_entry *entry) if (entry->action & ~(MEASURE | DONT_MEASURE)) return false; - if (entry->flags & ~(IMA_FUNC | IMA_UID | IMA_PCR | + if (entry->flags & ~(IMA_FUNC | IMA_UID | IMA_GID | IMA_PCR | IMA_KEYRINGS)) return false; @@ -1210,7 +1260,7 @@ static bool ima_validate_rule(struct ima_rule_entry *entry) if (entry->action & ~(MEASURE | DONT_MEASURE)) return false; - if (entry->flags & ~(IMA_FUNC | IMA_UID | IMA_PCR | + if (entry->flags & ~(IMA_FUNC | IMA_UID | IMA_GID | IMA_PCR | IMA_LABEL)) return false; @@ -1280,7 +1330,7 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) struct audit_buffer *ab; char *from; char *p; - bool uid_token; + bool eid_token; /* either euid or egid */ struct ima_template_desc *template_desc; int result = 0; @@ -1288,9 +1338,13 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) AUDIT_INTEGRITY_POLICY_RULE); entry->uid = INVALID_UID; + entry->gid = INVALID_GID; entry->fowner = INVALID_UID; + entry->fgroup = INVALID_GID; entry->uid_op = &uid_eq; + entry->gid_op = &gid_eq; entry->fowner_op = &uid_eq; + entry->fgroup_op = &gid_eq; entry->action = UNKNOWN; while ((p = strsep(&rule, " \t")) != NULL) { substring_t args[MAX_OPT_ARGS]; @@ -1508,12 +1562,12 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) fallthrough; case Opt_uid_eq: case Opt_euid_eq: - uid_token = (token == Opt_uid_eq) || - (token == Opt_uid_gt) || - (token == Opt_uid_lt); + eid_token = (token == Opt_euid_eq) || + (token == Opt_euid_gt) || + (token == Opt_euid_lt); - ima_log_string_op(ab, uid_token ? "uid" : "euid", - args[0].from, entry->uid_op); + ima_log_string_op(ab, eid_token ? "euid" : "uid", + args[0].from, token); if (uid_valid(entry->uid)) { result = -EINVAL; @@ -1528,8 +1582,43 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) (uid_t)lnum != lnum) result = -EINVAL; else - entry->flags |= uid_token - ? IMA_UID : IMA_EUID; + entry->flags |= eid_token + ? IMA_EUID : IMA_UID; + } + break; + case Opt_gid_gt: + case Opt_egid_gt: + entry->gid_op = &gid_gt; + fallthrough; + case Opt_gid_lt: + case Opt_egid_lt: + if ((token == Opt_gid_lt) || (token == Opt_egid_lt)) + entry->gid_op = &gid_lt; + fallthrough; + case Opt_gid_eq: + case Opt_egid_eq: + eid_token = (token == Opt_egid_eq) || + (token == Opt_egid_gt) || + (token == Opt_egid_lt); + + ima_log_string_op(ab, eid_token ? "egid" : "gid", + args[0].from, token); + + if (gid_valid(entry->gid)) { + result = -EINVAL; + break; + } + + result = kstrtoul(args[0].from, 10, &lnum); + if (!result) { + entry->gid = make_kgid(current_user_ns(), + (gid_t)lnum); + if (!gid_valid(entry->gid) || + (((gid_t)lnum) != lnum)) + result = -EINVAL; + else + entry->flags |= eid_token + ? IMA_EGID : IMA_GID; } break; case Opt_fowner_gt: @@ -1540,8 +1629,7 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) entry->fowner_op = &uid_lt; fallthrough; case Opt_fowner_eq: - ima_log_string_op(ab, "fowner", args[0].from, - entry->fowner_op); + ima_log_string_op(ab, "fowner", args[0].from, token); if (uid_valid(entry->fowner)) { result = -EINVAL; @@ -1559,6 +1647,32 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) entry->flags |= IMA_FOWNER; } break; + case Opt_fgroup_gt: + entry->fgroup_op = &gid_gt; + fallthrough; + case Opt_fgroup_lt: + if (token == Opt_fgroup_lt) + entry->fgroup_op = &gid_lt; + fallthrough; + case Opt_fgroup_eq: + ima_log_string_op(ab, "fgroup", args[0].from, token); + + if (gid_valid(entry->fgroup)) { + result = -EINVAL; + break; + } + + result = kstrtoul(args[0].from, 10, &lnum); + if (!result) { + entry->fgroup = make_kgid(current_user_ns(), + (gid_t)lnum); + if (!gid_valid(entry->fgroup) || + (((gid_t)lnum) != lnum)) + result = -EINVAL; + else + entry->flags |= IMA_FGROUP; + } + break; case Opt_obj_user: ima_log_string(ab, "obj_user", args[0].from); result = ima_lsm_rule_init(entry, args, @@ -1945,6 +2059,28 @@ int ima_policy_show(struct seq_file *m, void *v) seq_puts(m, " "); } + if (entry->flags & IMA_GID) { + snprintf(tbuf, sizeof(tbuf), "%d", __kgid_val(entry->gid)); + if (entry->gid_op == &gid_gt) + seq_printf(m, pt(Opt_gid_gt), tbuf); + else if (entry->gid_op == &gid_lt) + seq_printf(m, pt(Opt_gid_lt), tbuf); + else + seq_printf(m, pt(Opt_gid_eq), tbuf); + seq_puts(m, " "); + } + + if (entry->flags & IMA_EGID) { + snprintf(tbuf, sizeof(tbuf), "%d", __kgid_val(entry->gid)); + if (entry->gid_op == &gid_gt) + seq_printf(m, pt(Opt_egid_gt), tbuf); + else if (entry->gid_op == &gid_lt) + seq_printf(m, pt(Opt_egid_lt), tbuf); + else + seq_printf(m, pt(Opt_egid_eq), tbuf); + seq_puts(m, " "); + } + if (entry->flags & IMA_FOWNER) { snprintf(tbuf, sizeof(tbuf), "%d", __kuid_val(entry->fowner)); if (entry->fowner_op == &uid_gt) @@ -1956,6 +2092,17 @@ int ima_policy_show(struct seq_file *m, void *v) seq_puts(m, " "); } + if (entry->flags & IMA_FGROUP) { + snprintf(tbuf, sizeof(tbuf), "%d", __kgid_val(entry->fgroup)); + if (entry->fgroup_op == &gid_gt) + seq_printf(m, pt(Opt_fgroup_gt), tbuf); + else if (entry->fgroup_op == &gid_lt) + seq_printf(m, pt(Opt_fgroup_lt), tbuf); + else + seq_printf(m, pt(Opt_fgroup_eq), tbuf); + seq_puts(m, " "); + } + if (entry->flags & IMA_VALIDATE_ALGOS) { seq_puts(m, "appraise_algos="); ima_policy_show_appraise_algos(m, entry->allowed_algos); |