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mirror of https://gitlab.com/apparmor/apparmor synced 2025-08-22 01:57:43 +00:00

refactor: mount gen_policy_re

Do a minimal code refactoring (ie. no functional changes, just moving
code,adding boiler plate and glue) in preparation to fix
bug https://bugs.launchpad.net/apparmor/+bug/1597017

Bug Link: https://bugs.launchpad.net/apparmor/+bug/1597017

Signed-off-by: John Johansen <john.johansen@canonical.com>

- rebased to bba1a023bf
- fixed compiler warnings:
    <built-in>: In member function ‘int mnt_rule::gen_policy_new_mount(Profile&, int&, unsigned int, unsigned int)’:
    <built-in>: note: by argument 1 of type ‘const char*’ to ‘long unsigned int __builtin_strlen(const char*)’ declared here
    mount.cc:880:14: note: ‘class_mount_hdr’ declared here
      880 |         char class_mount_hdr[64];
Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>
Acked-by: John Johansen <john.johansen@canonical.com>
This commit is contained in:
John Johansen 2016-07-02 00:49:24 -07:00
parent bba1a023bf
commit f17e43392b
2 changed files with 290 additions and 173 deletions

View File

@ -583,6 +583,286 @@ void mnt_rule::warn_once(const char *name)
rule_t::warn_once(name, "mount rules not enforce");
}
int mnt_rule::gen_policy_remount(Profile &prof, int &count)
{
std::string mntbuf;
std::string devbuf;
std::string typebuf;
char flagsbuf[PATH_MAX + 3];
std::string optsbuf;
char class_mount_hdr[64];
const char *vec[5];
unsigned int tmpflags, tmpinv_flags;
int tmpallow;
sprintf(class_mount_hdr, "\\x%02x", AA_CLASS_MOUNT);
/* remount can't be conditional on device and type */
/* rule class single byte header */
mntbuf.assign(class_mount_hdr);
if (mnt_point) {
/* both device && mnt_point or just mnt_point */
if (!convert_entry(mntbuf, mnt_point))
goto fail;
vec[0] = mntbuf.c_str();
} else {
if (!convert_entry(mntbuf, device))
goto fail;
vec[0] = mntbuf.c_str();
}
/* skip device */
vec[1] = default_match_pattern;
/* skip type */
vec[2] = default_match_pattern;
tmpflags = flags;
tmpinv_flags = inv_flags;
if (tmpflags != MS_ALL_FLAGS)
tmpflags &= MS_REMOUNT_FLAGS;
if (tmpinv_flags != MS_ALL_FLAGS)
tmpflags &= MS_REMOUNT_FLAGS;
if (!build_mnt_flags(flagsbuf, PATH_MAX, tmpflags, tmpinv_flags))
goto fail;
vec[3] = flagsbuf;
if (opts)
tmpallow = AA_MATCH_CONT;
else
tmpallow = allow;
/* rule for match without required data || data MATCH_CONT */
if (!prof.policy.rules->add_rule_vec(deny, tmpallow,
audit | AA_AUDIT_MNT_DATA, 4,
vec, dfaflags, false))
goto fail;
count++;
if (opts) {
/* rule with data match required */
optsbuf.clear();
if (!build_mnt_opts(optsbuf, opts))
goto fail;
vec[4] = optsbuf.c_str();
if (!prof.policy.rules->add_rule_vec(deny, allow,
audit | AA_AUDIT_MNT_DATA,
5, vec, dfaflags, false))
goto fail;
count++;
}
return RULE_OK;
fail:
return RULE_ERROR;
}
int mnt_rule::gen_policy_bind_mount(Profile &prof, int &count)
{
std::string mntbuf;
std::string devbuf;
std::string typebuf;
char flagsbuf[PATH_MAX + 3];
std::string optsbuf;
char class_mount_hdr[64];
const char *vec[5];
unsigned int tmpflags, tmpinv_flags;
sprintf(class_mount_hdr, "\\x%02x", AA_CLASS_MOUNT);
/* bind mount rules can't be conditional on dev_type or data */
/* rule class single byte header */
mntbuf.assign(class_mount_hdr);
if (!convert_entry(mntbuf, mnt_point))
goto fail;
vec[0] = mntbuf.c_str();
if (!clear_and_convert_entry(devbuf, device))
goto fail;
vec[1] = devbuf.c_str();
/* skip type */
vec[2] = default_match_pattern;
tmpflags = flags;
tmpinv_flags = inv_flags;
if (tmpflags != MS_ALL_FLAGS)
tmpflags &= MS_BIND_FLAGS;
if (tmpinv_flags != MS_ALL_FLAGS)
tmpflags &= MS_BIND_FLAGS;
if (!build_mnt_flags(flagsbuf, PATH_MAX, tmpflags, tmpinv_flags))
goto fail;
vec[3] = flagsbuf;
if (!prof.policy.rules->add_rule_vec(deny, allow, audit, 4, vec,
dfaflags, false))
goto fail;
count++;
return RULE_OK;
fail:
return RULE_ERROR;
}
int mnt_rule::gen_policy_change_mount_type(Profile &prof, int &count)
{
std::string mntbuf;
std::string devbuf;
std::string typebuf;
char flagsbuf[PATH_MAX + 3];
std::string optsbuf;
char class_mount_hdr[64];
const char *vec[5];
unsigned int tmpflags, tmpinv_flags;
sprintf(class_mount_hdr, "\\x%02x", AA_CLASS_MOUNT);
/* change type base rules can not be conditional on device,
* device type or data
*/
/* rule class single byte header */
mntbuf.assign(class_mount_hdr);
if (!convert_entry(mntbuf, mnt_point))
goto fail;
vec[0] = mntbuf.c_str();
/* skip device and type */
vec[1] = default_match_pattern;
vec[2] = default_match_pattern;
tmpflags = flags;
tmpinv_flags = inv_flags;
if (tmpflags != MS_ALL_FLAGS)
tmpflags &= MS_MAKE_FLAGS;
if (tmpinv_flags != MS_ALL_FLAGS)
tmpflags &= MS_MAKE_FLAGS;
if (!build_mnt_flags(flagsbuf, PATH_MAX, tmpflags, tmpinv_flags))
goto fail;
vec[3] = flagsbuf;
if (!prof.policy.rules->add_rule_vec(deny, allow, audit, 4, vec,
dfaflags, false))
goto fail;
count++;
return RULE_OK;
fail:
return RULE_ERROR;
}
int mnt_rule::gen_policy_move_mount(Profile &prof, int &count)
{
std::string mntbuf;
std::string devbuf;
std::string typebuf;
char flagsbuf[PATH_MAX + 3];
std::string optsbuf;
char class_mount_hdr[64];
const char *vec[5];
unsigned int tmpflags, tmpinv_flags;
sprintf(class_mount_hdr, "\\x%02x", AA_CLASS_MOUNT);
/* mount move rules can not be conditional on dev_type,
* or data
*/
/* rule class single byte header */
mntbuf.assign(class_mount_hdr);
if (!convert_entry(mntbuf, mnt_point))
goto fail;
vec[0] = mntbuf.c_str();
if (!clear_and_convert_entry(devbuf, device))
goto fail;
vec[1] = devbuf.c_str();
/* skip type */
vec[2] = default_match_pattern;
tmpflags = flags;
tmpinv_flags = inv_flags;
if (tmpflags != MS_ALL_FLAGS)
tmpflags &= MS_MOVE_FLAGS;
if (tmpinv_flags != MS_ALL_FLAGS)
tmpflags &= MS_MOVE_FLAGS;
if (!build_mnt_flags(flagsbuf, PATH_MAX, tmpflags, tmpinv_flags))
goto fail;
vec[3] = flagsbuf;
if (!prof.policy.rules->add_rule_vec(deny, allow, audit, 4, vec,
dfaflags, false))
goto fail;
count++;
return RULE_OK;
fail:
return RULE_ERROR;
}
int mnt_rule::gen_policy_new_mount(Profile &prof, int &count)
{
std::string mntbuf;
std::string devbuf;
std::string typebuf;
char flagsbuf[PATH_MAX + 3];
std::string optsbuf;
char class_mount_hdr[64];
const char *vec[5];
unsigned int tmpflags, tmpinv_flags;
int tmpallow;
sprintf(class_mount_hdr, "\\x%02x", AA_CLASS_MOUNT);
/* rule class single byte header */
mntbuf.assign(class_mount_hdr);
if (!convert_entry(mntbuf, mnt_point))
goto fail;
vec[0] = mntbuf.c_str();
if (!clear_and_convert_entry(devbuf, device))
goto fail;
vec[1] = devbuf.c_str();
typebuf.clear();
if (!build_list_val_expr(typebuf, dev_type))
goto fail;
vec[2] = typebuf.c_str();
tmpflags = flags;
tmpinv_flags = inv_flags;
if (tmpflags != MS_ALL_FLAGS)
tmpflags &= ~MS_CMDS;
if (tmpinv_flags != MS_ALL_FLAGS)
tmpinv_flags &= ~MS_CMDS;
if (!build_mnt_flags(flagsbuf, PATH_MAX, tmpflags, tmpinv_flags))
goto fail;
vec[3] = flagsbuf;
if (opts)
tmpallow = AA_MATCH_CONT;
else
tmpallow = allow;
/* rule for match without required data || data MATCH_CONT */
if (!prof.policy.rules->add_rule_vec(deny, tmpallow,
audit | AA_AUDIT_MNT_DATA, 4,
vec, dfaflags, false))
goto fail;
count++;
if (opts) {
/* rule with data match required */
optsbuf.clear();
if (!build_mnt_opts(optsbuf, opts))
goto fail;
vec[4] = optsbuf.c_str();
if (!prof.policy.rules->add_rule_vec(deny, allow,
audit | AA_AUDIT_MNT_DATA,
5, vec, dfaflags, false))
goto fail;
count++;
}
return RULE_OK;
fail:
return RULE_ERROR;
}
int mnt_rule::gen_policy_re(Profile &prof)
{
std::string mntbuf;
@ -608,200 +888,32 @@ int mnt_rule::gen_policy_re(Profile &prof)
if ((allow & AA_MAY_MOUNT) && (flags & MS_REMOUNT)
&& !device && !dev_type) {
int tmpallow;
/* remount can't be conditional on device and type */
/* rule class single byte header */
mntbuf.assign(class_mount_hdr);
if (mnt_point) {
/* both device && mnt_point or just mnt_point */
if (!convert_entry(mntbuf, mnt_point))
goto fail;
vec[0] = mntbuf.c_str();
} else {
if (!convert_entry(mntbuf, device))
goto fail;
vec[0] = mntbuf.c_str();
}
/* skip device */
vec[1] = default_match_pattern;
/* skip type */
vec[2] = default_match_pattern;
tmpflags = flags;
tmpinv_flags = inv_flags;
if (tmpflags != MS_ALL_FLAGS)
tmpflags &= MS_REMOUNT_FLAGS;
if (tmpinv_flags != MS_ALL_FLAGS)
tmpflags &= MS_REMOUNT_FLAGS;
if (!build_mnt_flags(flagsbuf, PATH_MAX, tmpflags, tmpinv_flags))
if (gen_policy_remount(prof, count) == RULE_ERROR)
goto fail;
vec[3] = flagsbuf;
if (opts)
tmpallow = AA_MATCH_CONT;
else
tmpallow = allow;
/* rule for match without required data || data MATCH_CONT */
if (!prof.policy.rules->add_rule_vec(deny, tmpallow,
audit | AA_AUDIT_MNT_DATA, 4,
vec, dfaflags, false))
goto fail;
count++;
if (opts) {
/* rule with data match required */
optsbuf.clear();
if (!build_mnt_opts(optsbuf, opts))
goto fail;
vec[4] = optsbuf.c_str();
if (!prof.policy.rules->add_rule_vec(deny, allow,
audit | AA_AUDIT_MNT_DATA,
5, vec, dfaflags, false))
goto fail;
count++;
}
}
if ((allow & AA_MAY_MOUNT) && (flags & MS_BIND)
&& !dev_type && !opts) {
/* bind mount rules can't be conditional on dev_type or data */
/* rule class single byte header */
mntbuf.assign(class_mount_hdr);
if (!convert_entry(mntbuf, mnt_point))
if (gen_policy_bind_mount(prof, count) == RULE_ERROR)
goto fail;
vec[0] = mntbuf.c_str();
if (!clear_and_convert_entry(devbuf, device))
goto fail;
vec[1] = devbuf.c_str();
/* skip type */
vec[2] = default_match_pattern;
tmpflags = flags;
tmpinv_flags = inv_flags;
if (tmpflags != MS_ALL_FLAGS)
tmpflags &= MS_BIND_FLAGS;
if (tmpinv_flags != MS_ALL_FLAGS)
tmpflags &= MS_BIND_FLAGS;
if (!build_mnt_flags(flagsbuf, PATH_MAX, tmpflags, tmpinv_flags))
goto fail;
vec[3] = flagsbuf;
if (!prof.policy.rules->add_rule_vec(deny, allow, audit, 4, vec,
dfaflags, false))
goto fail;
count++;
}
if ((allow & AA_MAY_MOUNT) &&
(flags & (MS_UNBINDABLE | MS_PRIVATE | MS_SLAVE | MS_SHARED))
&& !device && !dev_type && !opts) {
/* change type base rules can not be conditional on device,
* device type or data
*/
/* rule class single byte header */
mntbuf.assign(class_mount_hdr);
if (!convert_entry(mntbuf, mnt_point))
if (gen_policy_change_mount_type(prof, count) == RULE_ERROR)
goto fail;
vec[0] = mntbuf.c_str();
/* skip device and type */
vec[1] = default_match_pattern;
vec[2] = default_match_pattern;
tmpflags = flags;
tmpinv_flags = inv_flags;
if (tmpflags != MS_ALL_FLAGS)
tmpflags &= MS_MAKE_FLAGS;
if (tmpinv_flags != MS_ALL_FLAGS)
tmpflags &= MS_MAKE_FLAGS;
if (!build_mnt_flags(flagsbuf, PATH_MAX, tmpflags, tmpinv_flags))
goto fail;
vec[3] = flagsbuf;
if (!prof.policy.rules->add_rule_vec(deny, allow, audit, 4, vec,
dfaflags, false))
goto fail;
count++;
}
if ((allow & AA_MAY_MOUNT) && (flags & MS_MOVE)
&& !dev_type && !opts) {
/* mount move rules can not be conditional on dev_type,
* or data
*/
/* rule class single byte header */
mntbuf.assign(class_mount_hdr);
if (!convert_entry(mntbuf, mnt_point))
if (gen_policy_move_mount(prof, count) == RULE_ERROR)
goto fail;
vec[0] = mntbuf.c_str();
if (!clear_and_convert_entry(devbuf, device))
goto fail;
vec[1] = devbuf.c_str();
/* skip type */
vec[2] = default_match_pattern;
tmpflags = flags;
tmpinv_flags = inv_flags;
if (tmpflags != MS_ALL_FLAGS)
tmpflags &= MS_MOVE_FLAGS;
if (tmpinv_flags != MS_ALL_FLAGS)
tmpflags &= MS_MOVE_FLAGS;
if (!build_mnt_flags(flagsbuf, PATH_MAX, tmpflags, tmpinv_flags))
goto fail;
vec[3] = flagsbuf;
if (!prof.policy.rules->add_rule_vec(deny, allow, audit, 4, vec,
dfaflags, false))
goto fail;
count++;
}
if ((allow & AA_MAY_MOUNT) &&
(flags | inv_flags) & ~MS_CMDS) {
int tmpallow;
/* generic mount if flags are set that are not covered by
* above commands
*/
/* rule class single byte header */
mntbuf.assign(class_mount_hdr);
if (!convert_entry(mntbuf, mnt_point))
if (gen_policy_new_mount(prof, count) == RULE_ERROR)
goto fail;
vec[0] = mntbuf.c_str();
if (!clear_and_convert_entry(devbuf, device))
goto fail;
vec[1] = devbuf.c_str();
typebuf.clear();
if (!build_list_val_expr(typebuf, dev_type))
goto fail;
vec[2] = typebuf.c_str();
tmpflags = flags;
tmpinv_flags = inv_flags;
if (tmpflags != MS_ALL_FLAGS)
tmpflags &= ~MS_CMDS;
if (tmpinv_flags != MS_ALL_FLAGS)
tmpinv_flags &= ~MS_CMDS;
if (!build_mnt_flags(flagsbuf, PATH_MAX, tmpflags, tmpinv_flags))
goto fail;
vec[3] = flagsbuf;
if (opts)
tmpallow = AA_MATCH_CONT;
else
tmpallow = allow;
/* rule for match without required data || data MATCH_CONT */
if (!prof.policy.rules->add_rule_vec(deny, tmpallow,
audit | AA_AUDIT_MNT_DATA, 4,
vec, dfaflags, false))
goto fail;
count++;
if (opts) {
/* rule with data match required */
optsbuf.clear();
if (!build_mnt_opts(optsbuf, opts))
goto fail;
vec[4] = optsbuf.c_str();
if (!prof.policy.rules->add_rule_vec(deny, allow,
audit | AA_AUDIT_MNT_DATA,
5, vec, dfaflags, false))
goto fail;
count++;
}
}
if (allow & AA_MAY_UMOUNT) {
/* rule class single byte header */

View File

@ -121,6 +121,11 @@
class mnt_rule: public rule_t {
int gen_policy_remount(Profile &prof, int &count);
int gen_policy_bind_mount(Profile &prof, int &count);
int gen_policy_change_mount_type(Profile &prof, int &count);
int gen_policy_move_mount(Profile &prof, int &count);
int gen_policy_new_mount(Profile &prof, int &count);
public:
char *mnt_point;
char *device;