[RFC][PATCH 6/6] SLIM: debug output

From: Kylene Jo Hall
Date: Mon Jul 24 2006 - 13:51:37 EST

This patch contains all the necessary pieces to add debugging output to
SLIM.

Signed-off-by: Mimi Zohar <zohar@xxxxxxxxxx>
Signed-off-by: Kylene Hall <kjhall@xxxxxxxxxx>
---
security/slim/slm_secfs.c | 117 +++++++
security/slim/slim_dbg.h | 16 +
security/slim/slm_main_dbg.c | 510 ++++++++++++++++++++++++++++-----
3 files changed, 580 insertions(+), 63 deletions(-

--- linux-2.6.18-rc1-dbg/security/slim/slm_main.c 2006-07-21 15:38:15.000000000 -0500
+++ linux-2.6.18-rc1-dbg/security/slim/slm_main_dbg.c 2006-07-21 15:07:48.000000000 -0500
@@ -39,6 +39,7 @@
static int secondary;
static DEFINE_SPINLOCK(slm_inode_sec_lock);

+unsigned int slm_debug = SLM_BASE;
static char *slm_xattr_name = "security.slim.level";
module_param(slm_xattr_name, charp, 0444);
MODULE_PARM_DESC(slm_xattr_name, "SLIM extended attribute");
@@ -152,10 +153,17 @@ static inline void do_revoke_file_wperm(
return;

isec = inode->i_security;
- if (!isec)
+ if (!isec) {
+ dprintk(SLM_VERBOSE, "%s: isec is null\n", __FUNCTION__);
return;
- if (is_lower_integrity(cur_level, &isec->level))
+ }
+ if (is_lower_integrity(cur_level, &isec->level)) {
file->f_mode &= ~FMODE_WRITE;
+ if (file->f_dentry->d_name.name)
+ dprintk(SLM_BASE, "pid %d - revoking write perm "
+ "for %s\n", current->pid,
+ file->f_dentry->d_name.name);
+ }
}

/*
@@ -200,16 +208,26 @@ static inline void do_revoke_mmap_wperm(
unsigned long end = mpnt->vm_end;
size_t len = end - start;
struct dentry *dentry = mpnt->vm_file->f_dentry;
+ struct inode *inode = dentry->d_inode;

if ((mpnt->vm_flags & (VM_WRITE | VM_MAYWRITE))
&& (mpnt->vm_flags & VM_SHARED)
&& (cur_level->iac_level < isec->level.iac_level)) {
if (strncmp(dentry->d_name.name, "SYSV", 4) == 0) {
+ dprintk(SLM_BASE, "%s: pid %d - unmap SYSV"
+ " shmem for %ld\n", __FUNCTION__,
+ current->pid, inode->i_ino);
down_write(&current->mm->mmap_sem);
do_munmap(current->mm, start, len);
up_write(&current->mm->mmap_sem);
- } else
- do_mprotect(start, len, PROT_READ);
+ } else {
+ dprintk(SLM_BASE,
+ "%s: pid %d - revoking write"
+ " perm for %s\n", __FUNCTION__,
+ current->pid, dentry->d_name.name);
+ if (do_mprotect(start, len, PROT_READ) < 0)
+ dprintk(SLM_BASE, "do_mprotect failed");
+ }
}
}

@@ -235,14 +253,18 @@ static void revoke_mmap_wperm(struct slm
continue;

isec = dentry->d_inode->i_security;
- if (!isec)
+ if (!isec) {
+ dprintk(SLM_VERBOSE, "%s: isec is null\n",
+ __FUNCTION__);
continue;
+ }

do_revoke_mmap_wperm(mpnt, isec, cur_level);
}
}

-static void do_demote_thread_entry(struct task_struct *thread_tsk)
+static void do_demote_thread_entry(struct task_struct *thread_tsk,
+ const char *relation)
{
struct slm_tsec_data *cur_tsec = current->security,
*thread_tsec = thread_tsk->security;
@@ -251,6 +273,8 @@ static void do_demote_thread_entry(struc
return;
if (current->mm == thread_tsk->mm)
return;
+ dprintk(SLM_INTEGRITY, "%s: demoting %s: pid %d\n",
+ __FUNCTION__, relation, thread_tsk->pid);
if (!thread_tsec)
return;

@@ -260,16 +284,16 @@ static void do_demote_thread_entry(struc
spin_unlock(&thread_tsec->lock);
}

-#define do_demote_thread_list(head, member) { \
+#define do_demote_thread_list(head, member, relation) { \
struct task_struct *thread_tsk; \
list_for_each_entry(thread_tsk, head, member) \
- do_demote_thread_entry(thread_tsk); \
+ do_demote_thread_entry(thread_tsk, relation); \
}

static void demote_threads(void)
{
- do_demote_thread_list(&current->sibling, sibling);
- do_demote_thread_list(&current->children, children);
+ do_demote_thread_list(&current->sibling, sibling, "sibling");
+ do_demote_thread_list(&current->children, children, "child");
}

/*
@@ -427,6 +451,8 @@ static int slm_get_xattr(struct dentry *
}
}

+ dprintk(SLM_VERBOSE, "iac %d - %s\n", level->iac_level,
+ slm_iac_str[level->iac_level]);
if (error < 0)
return -EINVAL;
return rc;
@@ -469,6 +495,9 @@ static void get_sock_level(struct dentry
rc = slm_get_xattr(dentry, level, &xattr_status);
if (rc) {
- if (xattr_status == -EOPNOTSUPP)
+ if (xattr_status == -EOPNOTSUPP) {
+ dprintk(SLM_INTEGRITY, "%s:%s - slm_get_xattr "
+ "not supported pid %d\n", __FUNCTION__,
+ dentry->d_name.name, current->pid);
set_level_exempt(level);
- else
+ } else
set_level_tsec_read(level, cur_tsec);
@@ -480,9 +509,11 @@ static void get_level(struct dentry *den
int rc, xattr_status = 0;

rc = slm_get_xattr(dentry, level, &xattr_status);
- if ((rc == INTEGRITY_FAIL) || (rc == INTEGRITY_NOLABEL))
+ if ((rc == INTEGRITY_FAIL) || (rc == INTEGRITY_NOLABEL)) {
+ dprintk(SLM_INTEGRITY, "%s: %s FAIL/NOLABEL (%d)\n",
+ __FUNCTION__, dentry->d_name.name, rc);
set_level_untrusted(level);
- else if (xattr_status == -EOPNOTSUPP)
+ } else if (xattr_status == -EOPNOTSUPP)
set_level_exempt(level);
else if (rc == -EINVAL) /* improperly formatted */
set_level_untrusted(level);
@@ -541,6 +572,8 @@ static void slm_get_level(struct dentry

if (is_isec_defined(isec)) {
memcpy(level, &isec->level, sizeof(struct slm_file_xattr));
+ dprintk(SLM_VERBOSE, "%s: %s level %d \n", __FUNCTION__,
+ dentry->d_name.name, level->iac_level);
return;
}

@@ -575,6 +608,9 @@ static struct slm_tsec_data *slm_init_ta
return NULL;
tsec->lock = SPIN_LOCK_UNLOCKED;
if (!cur_tsec) {
+ dprintk(SLM_VERBOSE,
+ "%s: pid %d current->pid %d cur_tsec\n",
+ __FUNCTION__, tsk->pid, current->pid);
tsec->iac_r = SLM_IAC_HIGHEST - 1;
tsec->iac_wx = SLM_IAC_HIGHEST - 1;
tsec->sac_w = SLM_SAC_NOTDEFINED + 1;
@@ -653,12 +689,28 @@ static int is_sac_greater_than_or_exempt
* Permit process to read file of equal or greater integrity
* otherwise, demote the process.
*/
-static void enforce_integrity_read(struct slm_file_xattr *level)
+static void enforce_integrity_read(struct slm_file_xattr *level,
+ const unsigned char *name,
+ struct task_struct *parent_tsk,
+ struct slm_tsec_data *parent_tsec)
{
struct slm_tsec_data *cur_tsec = current->security;

if (!is_iac_less_than_or_exempt(level, cur_tsec->iac_r)) {
/* Reading lower integrity, demote process */
+ dprintk(SLM_BASE, "ppid %d(%s p=%d-%s) "
+ " pid %d(%s p=%d-%s) demoting integrity to"
+ " iac=%d-%s(%s)\n",
+ parent_tsk->pid, parent_tsk->comm,
+ parent_tsec->iac_r,
+ (parent_tsec->iac_wx != parent_tsec->iac_r)
+ ? "GUARD" : slm_iac_str[parent_tsec->
+ iac_r],
+ current->pid, current->comm,
+ cur_tsec->iac_r, (cur_tsec->iac_wx != cur_tsec->iac_r)
+ ? "GUARD" : slm_iac_str[cur_tsec->iac_r],
+ level->iac_level, slm_iac_str[level->iac_level], name);
+
/* Even in the case of a integrity guard process. */
spin_lock(&cur_tsec->lock);
cur_tsec->iac_r = level->iac_level;
@@ -674,12 +726,26 @@ static void enforce_integrity_read(struc
* Permit process to read file of equal or lesser secrecy;
* otherwise, promote the process.
*/
-static void enforce_secrecy_read(struct slm_file_xattr *level)
+static void enforce_secrecy_read(struct slm_file_xattr *level,
+ const unsigned char *name,
+ struct task_struct *parent_tsk,
+ struct slm_tsec_data *parent_tsec)
{
struct slm_tsec_data *cur_tsec = current->security;

if (!is_sac_greater_than_or_exempt(level, cur_tsec->sac_rx)) {
/* Reading higher secrecy, promote process */
+ dprintk(SLM_BASE, "ppid %d(%s p=%d-%s) "
+ "pid %d(%s p=%d-%s) promoting secrecy to "
+ "p=%d-%s(%s)\n", parent_tsk->pid,
+ parent_tsk->comm, parent_tsec->sac_rx,
+ (parent_tsec->sac_w != parent_tsec->sac_rx)
+ ? "GUARD" : slm_sac_str[parent_tsec->
+ sac_rx],
+ current->pid, current->comm,
+ cur_tsec->sac_rx, (cur_tsec->sac_w != cur_tsec->sac_rx)
+ ? "GUARD" : slm_sac_str[cur_tsec->sac_rx],
+ level->sac_level, slm_sac_str[level->sac_level], name);
/* Even in the case of a secrecy guard process. */
spin_lock(&cur_tsec->lock);
cur_tsec->sac_rx = level->sac_level;
@@ -693,24 +759,43 @@ static void enforce_secrecy_read(struct
}
}

-static void do_task_may_read(struct slm_file_xattr *level)
+static void do_task_may_read(struct slm_file_xattr *level,
+ const unsigned char *name,
+ struct task_struct *parent_tsk,
+ struct slm_tsec_data *parent_tsec)
{
- enforce_integrity_read(level);
- enforce_secrecy_read(level);
+ enforce_integrity_read(level, name, parent_tsk, parent_tsec);
+ enforce_secrecy_read(level, name, parent_tsk, parent_tsec);
}

/*
* enforce: IWXAC(process) >= IAC(object)
* Permit process to write a file of equal or lesser integrity.
*/
-static int enforce_integrity_write(struct slm_file_xattr *level)
+static int enforce_integrity_write(struct slm_file_xattr *level,
+ const unsigned char *name,
+ struct task_struct *parent_tsk,
+ struct slm_tsec_data *parent_tsec)
{
struct slm_tsec_data *cur_tsec = current->security;

if (!(is_iac_greater_than_or_exempt(level, cur_tsec->iac_wx)
- || (level->iac_level == SLM_IAC_NOTDEFINED)))
+ || (level->iac_level == SLM_IAC_NOTDEFINED))) {
/* can't write higher integrity */
+ dprintk(SLM_BASE, "ppid %d(%s p=%d-%s) "
+ "pid %d(%s p=%d-%s) can't write higher "
+ "integrity iac=%d-%s(%s)\n",
+ parent_tsk->pid, parent_tsk->comm,
+ parent_tsec->iac_wx,
+ (parent_tsec->iac_wx != parent_tsec->iac_r)
+ ? "GUARD" : slm_iac_str[parent_tsec->
+ iac_wx],
+ current->pid, current->comm,
+ cur_tsec->iac_wx, (cur_tsec->iac_wx != cur_tsec->iac_r)
+ ? "GUARD" : slm_iac_str[cur_tsec->iac_wx],
+ level->iac_level, slm_iac_str[level->iac_level], name);
return -EACCES;
+ }
return 0;
}

@@ -718,42 +803,82 @@ static int enforce_integrity_write(struc
* enforce: SWAC(process) <= SAC(process)
* Permit process to write a file of equal or greater secrecy
*/
-static int enforce_secrecy_write(struct slm_file_xattr *level)
+static int enforce_secrecy_write(struct slm_file_xattr *level,
+ const unsigned char *name,
+ struct task_struct *parent_tsk,
+ struct slm_tsec_data *parent_tsec)
{
struct slm_tsec_data *cur_tsec = current->security;

- if (!is_sac_less_than_or_exempt(level, cur_tsec->sac_w))
+ if (!is_sac_less_than_or_exempt(level, cur_tsec->sac_w)) {
/* can't write lower secrecy */
+ dprintk(SLM_BASE, "ppid %d(%s p=%d-%s) "
+ "pid %d(%s p=%d-%s) can't write lower "
+ "secrecy sac=%d-%s(%s)\n",
+ parent_tsk->pid, parent_tsk->comm,
+ parent_tsec->sac_w,
+ (parent_tsec->sac_w != parent_tsec->sac_rx)
+ ? "GUARD" : slm_sac_str[parent_tsec->
+ sac_w],
+ current->pid, current->comm,
+ cur_tsec->sac_w, (cur_tsec->sac_w != cur_tsec->sac_rx)
+ ? "GUARD" : slm_sac_str[cur_tsec->sac_w],
+ level->sac_level, slm_sac_str[level->sac_level], name);
return -EACCES;
+ }
return 0;
}

-static int do_task_may_write(struct slm_file_xattr *level)
+static int do_task_may_write(struct slm_file_xattr *level,
+ const unsigned char *name,
+ struct task_struct *parent_tsk,
+ struct slm_tsec_data *parent_tsec)
{
int rc;

- rc = enforce_integrity_write(level);
+ rc = enforce_integrity_write(level, name, parent_tsk, parent_tsec);
if (rc < 0)
return rc;

- return enforce_secrecy_write(level);
+ return enforce_secrecy_write(level, name, parent_tsk, parent_tsec);
}

-static int slm_set_taskperm(int mask, struct slm_file_xattr *level)
+static int slm_set_taskperm(int mask, struct slm_file_xattr *level,
+ const unsigned char *name)
{
- struct slm_tsec_data *cur_tsec = current->security;
+ struct task_struct *parent_tsk = current->parent, new_tsk;
+ struct slm_tsec_data *cur_tsec = current->security,
+ *parent_tsec = NULL, new_tsec;
+ static int ictr;
int rc = 0;

if (!cur_tsec) {
+ dprintk(SLM_VERBOSE, "%s: calling init_task %d\n",
+ __FUNCTION__, ictr++);
cur_tsec = slm_init_task_with_lock(current);
if (!cur_tsec)
return -ENOMEM;
}

+ if (parent_tsk)
+ parent_tsec = parent_tsk->security;
+ else {
+ printk(KERN_INFO
+ "%s: current pid %d: parent_tsk is null\n",
+ __FUNCTION__, current->pid);
+ memset(&new_tsk, 0, sizeof(struct task_struct));
+ parent_tsk = &new_tsk;
+ }
+
+ if (!parent_tsec) {
+ memset(&new_tsec, 0, sizeof(struct slm_tsec_data));
+ parent_tsec = &new_tsec;
+ }
+
if (mask & MAY_READ)
- do_task_may_read(level);
+ do_task_may_read(level, name, parent_tsk, parent_tsec);
if ((mask & MAY_WRITE) || (mask & MAY_APPEND))
- rc = do_task_may_write(level);
+ rc = do_task_may_write(level, name, parent_tsk, parent_tsec);

return rc;
}
@@ -773,13 +898,19 @@ static int slm_file_permission(struct fi
return 0;
}

-static int is_untrusted_blk_access(struct inode *inode)
+static int is_untrusted_blk_access(struct inode *inode,
+ const unsigned char *fname)
{
struct slm_tsec_data *cur_tsec = current->security;

if (cur_tsec && (cur_tsec->iac_wx == SLM_IAC_UNTRUSTED)
- && S_ISBLK(inode->i_mode))
+ && S_ISBLK(inode->i_mode)) {
+ dprintk(SLM_BASE, "pid %d(%s p=%d-%s) deny access %s\n",
+ current->pid, current->comm,
+ cur_tsec->iac_wx, (cur_tsec->iac_wx != cur_tsec->iac_r)
+ ? "GUARD" : slm_iac_str[cur_tsec->iac_wx], fname);
return 1;
+ }
return 0;
}

@@ -791,8 +922,11 @@ static int is_untrusted_blk_access(struc
static int slm_inode_permission(struct inode *inode, int mask,
struct nameidata *nd)
{
- struct dentry *dentry;
+ char *path = NULL;
+ const unsigned char *fname = NULL;
+ struct dentry *dentry = NULL;
struct slm_file_xattr level;
+ int rc = 0;

if (S_ISDIR(inode->i_mode) && (mask & MAY_WRITE))
return 0;
@@ -801,16 +935,33 @@ static int slm_inode_permission(struct i
if (!dentry)
return 0;

- if (is_untrusted_blk_access(inode))
- return -EPERM;
+ if (nd) { /* preferably use fullname */
+ path = (char *)__get_free_page(GFP_KERNEL);
+ if (path)
+ fname = d_path(nd->dentry, nd->mnt, path, PAGE_SIZE);
+ }
+
+ if (!fname) /* no choice, use short name */
+ fname = (!dentry->d_name.name) ? dentry->d_iname :
+ dentry->d_name.name;
+
+ if (is_untrusted_blk_access(inode, fname)) {
+ rc = -EPERM;
+ goto out;
+ }

slm_get_level(dentry, &level);

/* measure all SYSTEM level integrity objects */
if (level.iac_level == SLM_IAC_SYSTEM)
- integrity_measure(dentry, NULL, mask);
+ integrity_measure(dentry, fname, mask);
+
+ rc = slm_set_taskperm(mask, &level, fname);

- return slm_set_taskperm(mask, &level);
+ out:
+ if (path)
+ free_page((unsigned long)path);
+ return rc;
}

/*
@@ -824,7 +975,7 @@ static int slm_inode_unlink(struct inode
return 0;

slm_get_level(dentry, &level);
- return slm_set_taskperm(MAY_WRITE, &level);
+ return slm_set_taskperm(MAY_WRITE, &level, dentry->d_name.name);
}

static void slm_inode_free_security(struct inode *inode)
@@ -845,22 +996,31 @@ static int slm_inode_create(struct inode
struct slm_isec_data *parent_isec = parent_dir->i_security;
struct slm_file_xattr *parent_level;

- if (!parent_isec)
+ if (!parent_isec) {
+ dprintk(SLM_VERBOSE, "%s: parent_isec is null\n", __FUNCTION__);
return 0;
+ }
parent_level = &parent_isec->level;

if (!cur_tsec) {
cur_tsec = slm_init_task(current, GFP_KERNEL);
if (!cur_tsec)
return -ENOMEM;
}

/*
* enforce: IWXAC(process) >= IAC(object)
* Permit process to write a file of equal or lesser integrity.
*/
- if (!is_iac_greater_than_or_exempt(parent_level, cur_tsec->iac_wx))
+ if (!is_iac_greater_than_or_exempt(parent_level, cur_tsec->iac_wx)) {
+ dprintk(SLM_INTEGRITY, "%s: prohibit current %s level "
+ "process writing into %s (%s level directory)\n",
+ __FUNCTION__, slm_iac_str[cur_tsec->iac_wx],
+ (!dentry->d_name.name)
+ ? " " : (char *)dentry->d_name.name,
+ slm_iac_str[parent_level->iac_level]);
return -EPERM;
+ }
return 0;
}

@@ -932,9 +1092,12 @@ static int slm_inode_init_security(struc

memset(&level, 0, sizeof(struct slm_file_xattr));

- if (is_isec_defined(parent_isec))
+ if (is_isec_defined(parent_isec)) {
memcpy(&level, &parent_isec->level,
sizeof(struct slm_file_xattr));
+ dprintk(SLM_VERBOSE, "%s: level %d\n", __FUNCTION__,
+ parent_isec->level.iac_level);
+ }

/* low integrity process wrote into a higher level directory */
if (cur_tsec->iac_wx < level.iac_level)
@@ -954,8 +1117,10 @@ static int slm_inode_init_security(struc
&& (cur_tsec->iac_wx != cur_tsec->iac_r))
set_level_exempt(&level);

- if (!isec)
+ if (!isec) {
+ dprintk(SLM_VERBOSE, "%s: isec is null\n", __FUNCTION__);
return 0;
+ }
spin_lock(&isec->lock);
memcpy(&isec->level, &level, sizeof(struct slm_file_xattr));
spin_unlock(&isec->lock);
@@ -1015,6 +1180,13 @@ static int slm_inode_mkdir(struct inode
if (cur_tsec->iac_wx < parent_level->iac_level) {
if (parent_level->iac_level == SLM_IAC_SYSTEM)
return -EACCES;
+
+ dprintk(SLM_VERBOSE, "%s:ppid %d (%s) %s - creating"
+ " lower integrity directory, than parent\n",
+ __FUNCTION__, current->pid, current->comm,
+ (!dentry->d_name.name)
+ ? "" : (char *)dentry->d_name.name);
+
}
return 0;
}
@@ -1035,8 +1207,13 @@ static int slm_inode_rename(struct inode
slm_get_level(parent_dentry, &parent_level);
dput(parent_dentry);

- if (is_lower_integrity(&old_level, &parent_level))
+ if (is_lower_integrity(&old_level, &parent_level)) {
+ dprintk(SLM_BASE, "%s: prohibit rename of %s (low"
+ " integrity) into %s (higher level directory)\n",
+ __FUNCTION__, old_dentry->d_name.name,
+ parent_dentry->d_name.name);
return -EPERM;
+ }
return 0;
}

@@ -1054,12 +1231,18 @@ int slm_inode_setxattr(struct dentry *de
if (strncmp(name, slm_xattr_name, strlen(slm_xattr_name)) != 0)
return 0;

- if (!cur_tsec)
+ if (!cur_tsec) {
+ dprintk(SLM_VERBOSE, "%s: cur_tsec is null\n", __FUNCTION__);
return 0;
+ }

if (!value)
return -EINVAL;

+ dprintk(SLM_VERBOSE, "%s: name %s value %s process:iac_r %s "
+ "iac_wx %s\n", __FUNCTION__, name, (char *)value,
+ slm_iac_str[cur_tsec->iac_r], slm_iac_str[cur_tsec->iac_wx]);
+
data = value + sizeof(time_t) + 1;

switch (cur_tsec->iac_wx) {
@@ -1096,8 +1279,10 @@ static void slm_inode_post_setxattr(stru

rc = slm_get_xattr(dentry, &level, &xattr_status);
slm_isec = dentry->d_inode->i_security;
- if (!slm_isec)
+ if (!slm_isec) {
+ dprintk(SLM_VERBOSE, "%s: isec is null\n", __FUNCTION__);
return;
+ }
spin_lock(&slm_isec->lock);
memcpy(&slm_isec->level, &level, sizeof(struct slm_file_xattr));
spin_unlock(&slm_isec->lock);
@@ -1133,12 +1318,21 @@ static int slm_inode_alloc_security(stru
*/
int slm_socket_create(int family, int type, int protocol, int kern)
{
- struct slm_tsec_data *cur_tsec = current->security;
+ struct task_struct *parent_tsk;
+ struct slm_tsec_data *cur_tsec = current->security, *parent_tsec;
struct slm_file_xattr level;

/* demoting only internet sockets */
if ((family != AF_UNIX) && (family != AF_NETLINK)) {
if (cur_tsec->iac_r > SLM_IAC_UNTRUSTED) {
+ parent_tsk = current->parent;
+ parent_tsec = parent_tsk->security;
+ dprintk(SLM_INTEGRITY,
+ "%s: ppid %d pid %d demoting "
+ "family %d type %d protocol %d kern %d"
+ " to untrusted.\n", __FUNCTION__,
+ parent_tsk->pid, current->pid, family,
+ type, protocol, kern);
spin_lock(&cur_tsec->lock);
cur_tsec->iac_r = SLM_IAC_UNTRUSTED;
cur_tsec->iac_wx = SLM_IAC_UNTRUSTED;
@@ -1163,12 +1357,17 @@ static void slm_socket_post_create(struc
struct inode *inode = SOCK_INODE(sock);
struct slm_isec_data *slm_isec = inode->i_security;

- if (!slm_isec)
+ if (!slm_isec) {
+ dprintk(SLM_VERBOSE, "%s: slm_isec is null\n", __FUNCTION__);
return;
+ }

if (family == PF_UNIX) {
- if (!cur_tsec) /* task created before LSM hooks enabled */
+ if (!cur_tsec) { /* task created before LSM hooks enabled */
+ dprintk(SLM_VERBOSE, "%s: cur_tsec is null\n",
+ __FUNCTION__);
return;
+ }
if (cur_tsec->iac_wx != cur_tsec->iac_r) { /* guard process */
spin_lock(&slm_isec->lock);
set_level_exempt(&slm_isec->level);
@@ -1218,19 +1417,40 @@ static int slm_task_post_setuid(uid_t ol

if (cur_tsec && flags == LSM_SETID_ID) {
/*set process to USER level integrity for everything but root */
+ dprintk(SLM_VERBOSE, "ruid %d euid %d suid %d "
+ "cur: uid %d euid %d suid %d\n",
+ old_ruid, old_euid, old_suid,
+ current->uid, current->euid, current->suid);
if ((cur_tsec->iac_r == cur_tsec->iac_wx)
- && (cur_tsec->iac_r == SLM_IAC_UNTRUSTED));
- else if (current->suid != 0) {
+ && (cur_tsec->iac_r == SLM_IAC_UNTRUSTED)) {
+ dprintk(SLM_INTEGRITY,
+ "Integrity: pid %d iac_r %d "
+ " iac_wx %d remains UNTRUSTED\n",
+ current->pid, cur_tsec->iac_r,
+ cur_tsec->iac_wx);
+ } else if (current->suid != 0) {
+ dprintk(SLM_INTEGRITY, "setting: pid %d iac_r %d "
+ " iac_wx %d to USER\n",
+ current->pid, cur_tsec->iac_r,
+ cur_tsec->iac_wx);
spin_lock(&cur_tsec->lock);
cur_tsec->iac_r = SLM_IAC_USER;
cur_tsec->iac_wx = SLM_IAC_USER;
spin_unlock(&cur_tsec->lock);
} else if ((current->uid == 0) && (old_ruid != 0)) {
+ dprintk(SLM_INTEGRITY, "setting: pid %d iac_r %d "
+ " iac_wx %d to SYSTEM\n",
+ current->pid, cur_tsec->iac_r,
+ cur_tsec->iac_wx);
spin_lock(&cur_tsec->lock);
cur_tsec->iac_r = SLM_IAC_SYSTEM;
cur_tsec->iac_wx = SLM_IAC_SYSTEM;
spin_unlock(&cur_tsec->lock);
- }
+ } else
+ dprintk(SLM_INTEGRITY, "%s: pid %d iac_r %d "
+ " iac_wx %d \n", __FUNCTION__,
+ current->pid, cur_tsec->iac_r,
+ cur_tsec->iac_wx);
}
return 0;
}
@@ -1238,7 +1458,9 @@ static int slm_task_post_setuid(uid_t ol
static inline int slm_setprocattr(struct task_struct *tsk,
char *name, void *value, size_t size)
{
+ dprintk(SLM_BASE, "%s: %s \n", __FUNCTION__, name);
return -EACCES;
+
}

static inline int slm_getprocattr(struct task_struct *tsk,
@@ -1271,13 +1493,68 @@ static void enforce_integrity_execute(st
struct slm_file_xattr *level)
{
struct slm_tsec_data *cur_tsec = current->security;
+ struct task_struct *parent_tsk = current->parent;
+ struct slm_tsec_data *parent_tsec = parent_tsk->security;

if (is_iac_less_than_or_exempt(level, cur_tsec->iac_wx)) {
+ if (!parent_tsec) {
+ dprintk(SLM_INTEGRITY,
+ "%s: pid %d(%s %d-%s) %s executing\n",
+ __FUNCTION__,
+ current->pid, current->comm,
+ cur_tsec->iac_wx,
+ (cur_tsec->iac_wx != cur_tsec->iac_r)
+ ? "GUARD" : slm_iac_str[cur_tsec->iac_wx],
+ bprm->filename);
+ } else
+ dprintk(SLM_INTEGRITY,
+ "%s: ppid %d(%s %d-%s) pid %d(%s %d-%s)"
+ " %s executing\n",
+ __FUNCTION__, parent_tsk->pid,
+ parent_tsk->comm,
+ (!parent_tsec) ? 0 : parent_tsec->iac_wx,
+ (parent_tsec->iac_wx != parent_tsec->iac_r)
+ ? "GUARD" : slm_iac_str[parent_tsec->
+ iac_wx],
+ current->pid, current->comm,
+ cur_tsec->iac_wx,
+ (cur_tsec->iac_wx != cur_tsec->iac_r)
+ ? "GUARD" : slm_iac_str[cur_tsec->iac_wx],
+ bprm->filename);
+
/* Being a guard process is not inherited */
spin_lock(&cur_tsec->lock);
cur_tsec->iac_r = cur_tsec->iac_wx;
spin_unlock(&cur_tsec->lock);
} else {
+ if (!parent_tsec) {
+ dprintk(SLM_BASE,
+ "%s: pid %d(%s %d-%s) %s executing, "
+ "demoting integrity to iac=%d-%s\n",
+ __FUNCTION__,
+ current->pid, current->comm,
+ cur_tsec->iac_wx,
+ (cur_tsec->iac_wx != cur_tsec->iac_r)
+ ? "GUARD" : slm_iac_str[cur_tsec->iac_wx],
+ bprm->filename, level->iac_level,
+ slm_iac_str[level->iac_level]);
+ } else
+ dprintk(SLM_BASE,
+ "%s: ppid %d(%s %d-%s) pid %d(%s %d-%s)"
+ " %s executing, demoting integrity to "
+ " iac=%d-%s\n",
+ __FUNCTION__, parent_tsk->pid,
+ parent_tsk->comm, parent_tsec->iac_wx,
+ (parent_tsec->iac_wx != parent_tsec->iac_r)
+ ? "GUARD" : slm_iac_str[parent_tsec->
+ iac_wx],
+ current->pid, current->comm,
+ cur_tsec->iac_wx,
+ (cur_tsec->iac_wx != cur_tsec->iac_r)
+ ? "GUARD" : slm_iac_str[cur_tsec->iac_wx],
+ bprm->filename, level->iac_level,
+ slm_iac_str[level->iac_level]);
+
spin_lock(&cur_tsec->lock);
cur_tsec->iac_r = level->iac_level;
cur_tsec->iac_wx = level->iac_level;
@@ -1291,10 +1568,25 @@ static void enforce_guard_integrity_exec
struct slm_file_xattr *level)
{
struct slm_tsec_data *cur_tsec = current->security;
+ struct task_struct *parent_tsk = current->parent;

if ((strcmp(bprm->filename, bprm->interp) != 0)
- && (level->guard.unlimited))
+ && (level->guard.unlimited)) {
+ dprintk(SLM_INTEGRITY, "%s:pid %d %s prohibiting "
+ "script from being an unlimited guard\n",
+ __FUNCTION__, current->pid, bprm->filename);
level->guard.unlimited = 0;
+ }
+
+ dprintk(SLM_INTEGRITY,
+ "%s: ppid %d pid %d %s (integrity guard)"
+ "cur: r %s wx %s new: r %s wx %s %s\n",
+ __FUNCTION__, parent_tsk->pid, current->pid,
+ bprm->filename, slm_iac_str[cur_tsec->iac_r],
+ slm_iac_str[cur_tsec->iac_wx],
+ slm_iac_str[level->guard.iac_r],
+ slm_iac_str[level->guard.iac_wx],
+ (level->guard.unlimited ? "unlimited" : "limited"));

if (level->guard.unlimited) {
spin_lock(&cur_tsec->lock);
@@ -1319,6 +1611,8 @@ static void enforce_secrecy_execute(stru
struct slm_file_xattr *level)
{
struct slm_tsec_data *cur_tsec = current->security;
+ struct task_struct *parent_tsk = current->parent;
+ struct slm_tsec_data *parent_tsec = parent_tsk->security;

if (is_sac_greater_than_or_exempt(level, cur_tsec->sac_rx)) {
/* Being a guard process is not inherited */
@@ -1326,6 +1620,35 @@ static void enforce_secrecy_execute(stru
cur_tsec->sac_w = cur_tsec->sac_rx;
spin_unlock(&cur_tsec->lock);
} else {
+ if (!parent_tsec) {
+ dprintk(SLM_SECRECY,
+ "%s: pid %d(%s %d-%s) %s "
+ " executing, promoting secrecy to sac=%d-%s\n",
+ __FUNCTION__, current->pid,
+ current->comm, cur_tsec->sac_rx,
+ (cur_tsec->sac_w != cur_tsec->sac_rx)
+ ? "GUARD" : slm_sac_str[cur_tsec->
+ sac_rx],
+ bprm->filename, level->sac_level,
+ slm_sac_str[level->sac_level]);
+ } else
+ dprintk(SLM_SECRECY,
+ "%s: ppid %d(%s %d-%s) pid %d(%s %d-%s) %s"
+ "executing, promoting secrecy to sac=%d-%s\n",
+ __FUNCTION__, parent_tsk->pid,
+ parent_tsk->comm,
+ parent_tsec->sac_rx,
+ (parent_tsec->sac_w != parent_tsec->sac_rx)
+ ? "GUARD" :
+ slm_sac_str[parent_tsec->sac_rx],
+ current->pid, current->comm,
+ cur_tsec->sac_rx,
+ (cur_tsec->sac_w != cur_tsec->sac_rx)
+ ? "GUARD" : slm_sac_str[cur_tsec->
+ sac_rx],
+ bprm->filename, level->sac_level,
+ slm_sac_str[level->sac_level]);
+
spin_lock(&cur_tsec->lock);
cur_tsec->sac_rx = level->sac_level;
cur_tsec->sac_w = level->sac_level;
@@ -1341,7 +1664,16 @@ static void enforce_guard_secrecy_execut
struct slm_file_xattr *level)
{
struct slm_tsec_data *cur_tsec = current->security;
+ struct task_struct *parent_tsk = current->parent;

+ dprintk(SLM_SECRECY,
+ "%s: ppid %d pid %d %s (secrecy guard)"
+ "cur: rx %s w %s new: rx %s w %s\n", __FUNCTION__,
+ parent_tsk->pid, current->pid, bprm->filename,
+ slm_sac_str[cur_tsec->sac_rx],
+ slm_sac_str[cur_tsec->sac_w],
+ slm_sac_str[level->guard.sac_rx],
+ slm_sac_str[level->guard.sac_w]);
/*
* set low write secrecy range,
* not less than current value, prevent leaking data
@@ -1366,9 +1698,15 @@ static int slm_bprm_check_security(struc

/* Special case interpreters */
if (strcmp(bprm->filename, bprm->interp) != 0) {
- if (!cur_tsec->script_dentry)
+ dprintk(SLM_INTEGRITY,
+ "%s: executing %s (interp: %s)\n",
+ __FUNCTION__, bprm->filename, bprm->interp);
+ if (!cur_tsec->script_dentry) {
+ dprintk(SLM_INTEGRITY,
+ "%s: NULL script_dentry %s\n",
+ __FUNCTION__, bprm->filename);
return 0;
- else
+ } else
dentry = cur_tsec->script_dentry;
} else {
dentry = bprm->file->f_dentry;
@@ -1376,6 +1714,9 @@ static int slm_bprm_check_security(struc
}

slm_get_level(dentry, &level);
+ dprintk(SLM_INTEGRITY, "%s: %s level iac %d - %s\n",
+ __FUNCTION__, bprm->filename, level.iac_level,
+ slm_iac_str[level.iac_level]);

/* slm_inode_permission measured all SYSTEM level integrity objects */
if (level.iac_level != SLM_IAC_SYSTEM)
@@ -1384,8 +1725,14 @@ static int slm_bprm_check_security(struc
/* Possible return codes: PERMIT, DENY, NOLABEL */
switch (integrity_verify_data(dentry)) {
case INTEGRITY_FAIL:
+ dprintk(SLM_BASE,
+ "%s: %s (Integrity status: FAIL)\n",
+ __FUNCTION__, bprm->filename);
return -EACCES;
case INTEGRITY_NOLABEL:
+ dprintk(SLM_BASE,
+ "%s: %s (Integrity status: NOLABEL)\n",
+ __FUNCTION__, bprm->filename);
level.iac_level = SLM_IAC_UNTRUSTED;
}

@@ -1423,8 +1770,12 @@ static inline int slm_capable(struct tas

/* Derived from include/linux/sched.h:capable. */
if (cap_raised(tsk->cap_effective, cap)) {
- if ((tsec->iac_wx == SLM_IAC_UNTRUSTED) && (cap == CAP_SYS_ADMIN))
+ if (tsec->iac_wx == SLM_IAC_UNTRUSTED) {
+ dprintk(SLM_VERBOSE, "%s: pid %d %s requested cap %d\n",
+ __FUNCTION__, tsk->pid, tsk->comm, cap);
+ if (cap == CAP_SYS_ADMIN)
return -EACCES;
+ }
return 0;
}
return -EPERM;
@@ -1466,6 +1817,8 @@ static int slm_shm_alloc_security(struct
else
set_level_tsec_write(&isec->level, cur_tsec);
perm->security = isec;
+ dprintk(SLM_INTEGRITY, "%s: level %d \n", __FUNCTION__,
+ isec->level.iac_level);

return 0;
}
@@ -1512,7 +1865,7 @@ static int slm_shm_shmctl(struct shmid_k
get_level(dentry, &perm_isec->level);
}

- return slm_set_taskperm(MAY_READ | MAY_WRITE, &perm_isec->level);
+ return slm_set_taskperm(MAY_READ | MAY_WRITE, &perm_isec->level, NULL);
}

/*
@@ -1546,8 +1899,12 @@ static int slm_shm_shmat(struct shmid_ke
get_level(dentry, &perm_isec->level);
}

- rc = slm_set_taskperm(mask, &perm_isec->level);
+ rc = slm_set_taskperm(mask, &perm_isec->level, NULL);

+ dprintk(SLM_INTEGRITY,
+ "%s: %d mask %d level %d replace %d\n",
+ __FUNCTION__, shp->id, mask,
+ perm_isec->level.iac_level, isec->level.iac_level);
spin_lock(&isec->lock);
memcpy(&isec->level, &perm_isec->level, sizeof(struct slm_file_xattr));
spin_unlock(&isec->lock);
@@ -1593,33 +1950,60 @@ static int __init init_slm(void)

error = strncmp(slm_xattr_name, security_prefix,
strlen(security_prefix));
- if (error != 0)
+ if (error != 0) {
+ dprintk(SLM_BASE,
+ "%s: Invalid slm_xattr_name - %s\n",
+ __FUNCTION__, slm_xattr_name);
return -EINVAL;
+ }

error = slm_init_secfs();
- if (error < 0)
+ if (error < 0) {
+ dprintk(SLM_BASE, "%s: Error registering secfs\n",
+ __FUNCTION__);
return error;
+ }
+ error = slm_init_debugfs();
+ if (error < 0)
+ dprintk(SLM_BASE,
+ "%s: Error registering debugfs\n", __FUNCTION__);

if (register_security(&slm_security_ops)) {
if (mod_reg_security(MY_NAME, &slm_security_ops)) {
+ dprintk(SLM_BASE,
+ "%s: security hooks registration "
+ "failed\n", __FUNCTION__);
slm_cleanup_secfs();
+ slm_cleanup_debugfs();
return -EINVAL;
}
secondary = 1;
}
+ dprintk(SLM_BASE, "%s: registered security hooks\n", __FUNCTION__);
return 0;
}

static void __exit cleanup_slm(void)
{
slm_cleanup_secfs();
- if (secondary)
- mod_unreg_security(MY_NAME, &slm_security_ops);
- else
- unregister_security(&slm_security_ops);
+ slm_cleanup_debugfs();
+ if (secondary) {
+ if (mod_unreg_security(MY_NAME, &slm_security_ops))
+ dprintk(SLM_BASE,
+ "%s: failure unregistering module "
+ "with primary module.\n", __FUNCTION__);
+ } else if (unregister_security(&slm_security_ops)) {
+ dprintk(SLM_BASE,
+ "%s: failure unregistering module "
+ "with the kernel\n", __FUNCTION__);
+ }
+ dprintk(SLM_BASE, "%s: completed \n", __FUNCTION__);
}

module_init(init_slm);
module_exit(cleanup_slm);

+module_param(slm_debug, uint, 1);
+MODULE_DESCRIPTION("Simple Linux Integrity Module");
+
MODULE_LICENSE("GPL");
--- linux-2.6.18-rc1-dbg/security/slim/slim.h 2006-07-21 15:36:52.000000000 -0500
+++ linux-2.6.18-rc1-dbg/security/slim/slim_dbg.h 2006-07-21 15:35:21.000000000 -0500
@@ -100,3 +100,19 @@ extern int slm_init_config(void);

extern __init int slm_init_secfs(void);
extern __exit void slm_cleanup_secfs(void);
+
+extern __init int slm_init_debugfs(void);
+extern __exit void slm_cleanup_debugfs(void);
+
+extern unsigned int slm_debug;
+enum slm_debug_level {
+ SLM_BASE = 1,
+ SLM_INTEGRITY = 2,
+ SLM_SECRECY = 4,
+ SLM_VERBOSE = 8,
+};
+
+#undef dprintk
+#define dprintk(level, format, a...) \
+ if (slm_debug & level) \
+ printk(KERN_INFO format, ##a)
--- linux-2.6.17/security/slim/slm_secfs.c 2006-07-13 16:28:17.000000000 -0700
+++ linux-2.6.17/security/slim/slm_secfs.c 2006-07-13 16:27:33.000000000 -0700
@@ -19,6 +19,8 @@
#include "slim.h"

static struct dentry *slim_sec_dir, *slim_level;
+static struct dentry *slim_debug_dir, *slim_integrity, *slim_secrecy,
+ *slim_verbose;

static ssize_t slm_read_level(struct file *file, char __user *buf,
size_t buflen, loff_t *ppos)
@@ -48,10 +50,85 @@ static ssize_t slm_read_level(struct fil
return len;
}

+static int slm_open_debug(struct inode *inode, struct file *file)
+{
+ if (inode->u.generic_ip)
+ file->private_data = inode->u.generic_ip;
+ return 0;
+}
+
+static ssize_t slm_read_debug(struct file *file, char __user * buf,
+ size_t buflen, loff_t * ppos)
+{
+ ssize_t len = 0;
+ enum slm_debug_level type = (enum slm_debug_level)file->private_data;
+ char *page = (char *)__get_free_page(GFP_KERNEL);
+
+ if (!page)
+ return -ENOMEM;
+
+ switch(type) {
+ case SLM_INTEGRITY:
+ len = sprintf(page, "slm_debug: integrity %s\n",
+ ((slm_debug & SLM_INTEGRITY) == SLM_INTEGRITY)
+ ? "ON" : "OFF");
+ break;
+ case SLM_SECRECY:
+ len = sprintf(page, "slm_debug: secrecy %s\n",
+ ((slm_debug & SLM_SECRECY) == SLM_SECRECY)
+ ? "ON" : "OFF");
+ break;
+ case SLM_VERBOSE:
+ len = sprintf(page, "evm_debug: verbose %s\n",
+ ((slm_debug & SLM_VERBOSE) == SLM_VERBOSE)
+ ? "ON" : "OFF");
+ break;
+ default:
+ break;
+ }
+ len = simple_read_from_buffer(buf, buflen, ppos, page, len);
+ free_page((unsigned long)page);
+ return len;
+}
+
+static ssize_t slm_write_debug(struct file *file, const char __user * buf,
+ size_t buflen, loff_t * ppos)
+{
+ char flag;
+ enum slm_debug_level type = (enum slm_debug_level)file->private_data;
+
+ if (copy_from_user(&flag, buf, 1))
+ return -EFAULT;
+
+ switch(type) {
+ case SLM_INTEGRITY:
+ slm_debug = (flag == '0') ? slm_debug & ~SLM_INTEGRITY :
+ slm_debug | SLM_INTEGRITY;
+ break;
+ case SLM_SECRECY:
+ slm_debug = (flag == '0') ? slm_debug & ~SLM_SECRECY :
+ slm_debug | SLM_SECRECY;
+ break;
+ case SLM_VERBOSE:
+ slm_debug = (flag == '0') ? slm_debug & ~SLM_VERBOSE :
+ slm_debug | SLM_VERBOSE;
+ break;
+ default:
+ break;
+ }
+ return buflen;
+}
+
static struct file_operations slm_level_ops = {
.read = slm_read_level,
};

+static struct file_operations slm_debug_ops = {
+ .read = slm_read_debug,
+ .write = slm_write_debug,
+ .open = slm_open_debug,
+};
+
int __init slm_init_secfs(void)
{
slim_sec_dir = securityfs_create_dir("slim", NULL);
@@ -66,8 +143,48 @@ int __init slm_init_secfs(void)
return 0;
}

+int __init slm_init_debugfs(void)
+{
+ slim_debug_dir = debugfs_create_dir("slim", NULL);
+ if (!slim_debug_dir || IS_ERR(slim_debug_dir))
+ return -EFAULT;
+
+ slim_integrity = debugfs_create_file("integrity", S_IRUSR | S_IRGRP,
+ slim_debug_dir, (void *)SLM_INTEGRITY,
+ &slm_debug_ops);
+ if (!slim_integrity || IS_ERR(slim_integrity))
+ goto out_del_debugdir;
+ slim_secrecy = debugfs_create_file("secrecy", S_IRUSR | S_IRGRP,
+ slim_debug_dir, (void *)SLM_SECRECY,
+ &slm_debug_ops);
+ if (!slim_secrecy || IS_ERR(slim_secrecy))
+ goto out_del_integrity;
+ slim_verbose = debugfs_create_file("verbose", S_IRUSR | S_IRGRP,
+ slim_debug_dir, (void *)SLM_VERBOSE,
+ &slm_debug_ops);
+ if (!slim_verbose || IS_ERR(slim_verbose))
+ goto out_del_secrecy;
+ return 0;
+
+out_del_secrecy:
+ debugfs_remove(slim_secrecy);
+out_del_integrity:
+ debugfs_remove(slim_integrity);
+out_del_debugdir:
+ debugfs_remove(slim_debug_dir);
+ return -EFAULT;
+}
+
void __exit slm_cleanup_secfs(void)
{
securityfs_remove(slim_level);
securityfs_remove(slim_sec_dir);
}
+
+void __exit slm_cleanup_debugfs(void)
+{
+ debugfs_remove(slim_verbose);
+ debugfs_remove(slim_secrecy);
+ debugfs_remove(slim_integrity);
+ debugfs_remove(slim_debug_dir);
+}


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