* [PATCH V8 0/3] Add support for measuring the boot command line during kexec_file_load @ 2019-06-17 18:37 Prakhar Srivastava 2019-06-17 18:37 ` [PATCH V9 1/3] IMA:Define a new hook to measure the kexec boot command line arguments Prakhar Srivastava ` (2 more replies) 0 siblings, 3 replies; 9+ messages in thread From: Prakhar Srivastava @ 2019-06-17 18:37 UTC (permalink / raw) To: linux-integrity, linux-security-module, linux-kernel Cc: zohar, roberto.sassu, Prakhar Srivastava The kexec boot command line arguments are not currently being measured. Currently during soft reboot(kexec) - the PCRS are not reset - the command line arguments used for the next kernel are not measured. This gives the impression to the secure boot attestation that a cold boot took place. For secure boot attestation, it is necessary to measure the kernel command line. For cold boot, the boot loader can be enhanced to measure these parameters. (https://mjg59.dreamwidth.org/48897.html) This patch set aims to address measuring the boot command line during soft reboot(kexec_file_load). To achive the above the patch series does the following -Add a new ima hook: ima_kexec_cmdline which measures the cmdline args into the ima log, behind a new ima policy entry KEXEC_CMDLINE. The kexec cmdline hash is stored in the "d-ng" field of the template data. -Since the cmldine args cannot be appraised, a new template field(buf) is added. The template field contains the buffer passed(cmldine args), which can be used to appraise/attest at a later stage. The kexec cmdline buffer is stored as HEX in the buf field of the event_data. -Call the ima_kexec_cmdline(...) hook from kexec_file_load call. The ima logs need to be carried over to the next kernel, which will be followed up by other patchsets for x86_64 and arm64. The kexec cmdline hash is stored in the "d-ng" field of the template data. and can be verified using sudo cat /sys/kernel/security/integrity/ima/ascii_runtime_measurements | grep kexec-cmdline | cut -d' ' -f 6 | xxd -r -p | sha256sum Changelog: V9(since V8): - code cleanup V8(since V7): - added a new ima template name "ima-buf" - code cleanup V7: - rebased to next-queued-testing https://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity.git/log/?h=next-queued-testing V6: -add a new ima hook and policy to measure the cmdline args(ima_kexec_cmdline) -add a new template field buf to contain the buffer measured. [suggested by Mimi Zohar] add new fields to ima_event_data to store/read buffer data. [suggested by Roberto] -call ima_kexec_cmdline from kexec_file_load path v5: -add a new ima hook and policy to measure the cmdline args(ima_kexec_cmdline) -add a new template field buf to contain the buffer measured. [suggested by Mimi Zohar] -call ima_kexec_cmdline from kexec_file_load path v4: - per feedback from LSM community, removed the LSM hook and renamed the IMA policy to KEXEC_CMDLINE v3: (rebase changes to next-general) - Add policy checks for buffer[suggested by Mimi Zohar] - use the IMA_XATTR to add buffer - Add kexec_cmdline used for kexec file load - Add an LSM hook to allow usage by other LSM.[suggestd by Mimi Zohar] v2: - Add policy checks for buffer[suggested by Mimi Zohar] - Add an LSM hook to allow usage by other LSM.[suggestd by Mimi Zohar] - use the IMA_XATTR to add buffer instead of sig template v1: -Add kconfigs to control the ima_buffer_check -measure the cmdline args suffixed with the kernel file name -add the buffer to the template sig field. Prakhar Srivastava (3): Add a new ima hook ima_kexec_cmdline to measure cmdline args add a new ima template field buf call ima_kexec_cmdline to measure the cmdline args Documentation/ABI/testing/ima_policy | 1 + Documentation/security/IMA-templates.rst | 2 +- include/linux/ima.h | 2 + kernel/kexec_file.c | 8 ++- security/integrity/ima/ima.h | 3 + security/integrity/ima/ima_api.c | 5 +- security/integrity/ima/ima_init.c | 2 +- security/integrity/ima/ima_main.c | 80 +++++++++++++++++++++++ security/integrity/ima/ima_policy.c | 9 +++ security/integrity/ima/ima_template.c | 2 + security/integrity/ima/ima_template_lib.c | 20 ++++++ security/integrity/ima/ima_template_lib.h | 4 ++ 12 files changed, 131 insertions(+), 7 deletions(-) -- 2.17.1 ^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH V9 1/3] IMA:Define a new hook to measure the kexec boot command line arguments 2019-06-17 18:37 [PATCH V8 0/3] Add support for measuring the boot command line during kexec_file_load Prakhar Srivastava @ 2019-06-17 18:37 ` Prakhar Srivastava 2019-06-19 17:46 ` prakhar srivastava 2019-06-17 18:37 ` [PATCH V9 2/3] IMA:Define a new template field buf Prakhar Srivastava 2019-06-17 18:37 ` [PATCH V9 3/3] KEXEC:Call ima_kexec_cmdline to measure the boot command line args Prakhar Srivastava 2 siblings, 1 reply; 9+ messages in thread From: Prakhar Srivastava @ 2019-06-17 18:37 UTC (permalink / raw) To: linux-integrity, linux-security-module, linux-kernel Cc: zohar, roberto.sassu, Prakhar Srivastava Currently during soft reboot(kexec_file_load) boot command line arguments are not measured. Define hooks needed to measure kexec command line arguments during soft reboot(kexec_file_load). - A new ima hook ima_kexec_cmdline is defined to be called by the kexec code. - A new function process_buffer_measurement is defined to measure the buffer hash into the IMA measurement list. - A new func policy KEXEC_CMDLINE is defined to control the measurement.[Suggested by Mimi] Signed-off-by: Prakhar Srivastava <prsriva02@gmail.com> --- Documentation/ABI/testing/ima_policy | 1 + include/linux/ima.h | 2 + security/integrity/ima/ima.h | 1 + security/integrity/ima/ima_api.c | 1 + security/integrity/ima/ima_main.c | 74 ++++++++++++++++++++++++++++ security/integrity/ima/ima_policy.c | 7 +++ 6 files changed, 86 insertions(+) diff --git a/Documentation/ABI/testing/ima_policy b/Documentation/ABI/testing/ima_policy index b383c1763610..fc376a323908 100644 --- a/Documentation/ABI/testing/ima_policy +++ b/Documentation/ABI/testing/ima_policy @@ -28,6 +28,7 @@ Description: base: func:= [BPRM_CHECK][MMAP_CHECK][CREDS_CHECK][FILE_CHECK][MODULE_CHECK] [FIRMWARE_CHECK] [KEXEC_KERNEL_CHECK] [KEXEC_INITRAMFS_CHECK] + [KEXEC_CMDLINE] mask:= [[^]MAY_READ] [[^]MAY_WRITE] [[^]MAY_APPEND] [[^]MAY_EXEC] fsmagic:= hex value diff --git a/include/linux/ima.h b/include/linux/ima.h index fd9f7cf4cdf5..b42f5a006042 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -26,6 +26,7 @@ extern int ima_read_file(struct file *file, enum kernel_read_file_id id); extern int ima_post_read_file(struct file *file, void *buf, loff_t size, enum kernel_read_file_id id); extern void ima_post_path_mknod(struct dentry *dentry); +extern void ima_kexec_cmdline(const void *buf, int size); #ifdef CONFIG_IMA_KEXEC extern void ima_add_kexec_buffer(struct kimage *image); @@ -92,6 +93,7 @@ static inline void ima_post_path_mknod(struct dentry *dentry) return; } +static inline void ima_kexec_cmdline(const void *buf, int size) {} #endif /* CONFIG_IMA */ #ifndef CONFIG_IMA_KEXEC diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index 18b48a6d0b80..a4ad1270bffa 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -185,6 +185,7 @@ static inline unsigned long ima_hash_key(u8 *digest) hook(KEXEC_KERNEL_CHECK) \ hook(KEXEC_INITRAMFS_CHECK) \ hook(POLICY_CHECK) \ + hook(KEXEC_CMDLINE) \ hook(MAX_CHECK) #define __ima_hook_enumify(ENUM) ENUM, diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c index 78eb11c7ac07..ea7d8cbf712f 100644 --- a/security/integrity/ima/ima_api.c +++ b/security/integrity/ima/ima_api.c @@ -176,6 +176,7 @@ void ima_add_violation(struct file *file, const unsigned char *filename, * subj=, obj=, type=, func=, mask=, fsmagic= * subj,obj, and type: are LSM specific. * func: FILE_CHECK | BPRM_CHECK | CREDS_CHECK | MMAP_CHECK | MODULE_CHECK + * | KEXEC_CMDLINE * mask: contains the permission mask * fsmagic: hex value * diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index af341a80118f..1e233417a7af 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -605,6 +605,80 @@ int ima_load_data(enum kernel_load_data_id id) return 0; } +/* + * process_buffer_measurement - Measure the buffer to ima log. + * @buf: pointer to the buffer that needs to be added to the log. + * @size: size of buffer(in bytes). + * @eventname: event name to be used for the buffer entry. + * @cred: a pointer to a credentials structure for user validation. + * @secid: the secid of the task to be validated. + * + * Based on policy, the buffer is measured into the ima log. + */ +static void process_buffer_measurement(const void *buf, int size, + const char *eventname, + const struct cred *cred, u32 secid) +{ + int ret = 0; + struct ima_template_entry *entry = NULL; + struct integrity_iint_cache iint = {}; + struct ima_event_data event_data = {.iint = &iint }; + struct ima_template_desc *template_desc = NULL; + struct { + struct ima_digest_data hdr; + char digest[IMA_MAX_DIGEST_SIZE]; + } hash = {}; + int violation = 0; + int pcr = CONFIG_IMA_MEASURE_PCR_IDX; + int action = 0; + + action = ima_get_action(NULL, cred, secid, 0, KEXEC_CMDLINE, &pcr, + &template_desc); + if (!(action & IMA_MEASURE)) + goto out; + + event_data.filename = eventname; + + iint.ima_hash = &hash.hdr; + iint.ima_hash->algo = ima_hash_algo; + iint.ima_hash->length = hash_digest_size[ima_hash_algo]; + + ret = ima_calc_buffer_hash(buf, size, iint.ima_hash); + if (ret < 0) + goto out; + + ret = ima_alloc_init_template(&event_data, &entry, template_desc); + if (ret < 0) + goto out; + + if (action & IMA_MEASURE) + ret = ima_store_template(entry, violation, NULL, buf, pcr); + + if (ret < 0) + ima_free_template_entry(entry); + +out: + return; +} + +/** + * ima_kexec_cmdline - measure kexec cmdline boot args + * @buf: pointer to buffer + * @size: size of buffer + * + * Buffers can only be measured, not appraised. + */ +void ima_kexec_cmdline(const void *buf, int size) +{ + u32 secid; + + if (buf && size != 0) { + security_task_getsecid(current, &secid); + process_buffer_measurement(buf, size, "kexec-cmdline", + current_cred(), secid); + } +} + static int __init init_ima(void) { int error; diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index fd9b01881d17..4e8bb7eecd08 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -292,6 +292,11 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode, { int i; + if (func == KEXEC_CMDLINE) { + if ((rule->flags & IMA_FUNC) && (rule->func == func)) + return true; + return false; + } if ((rule->flags & IMA_FUNC) && (rule->func != func && func != POST_SETATTR)) return false; @@ -880,6 +885,8 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) entry->func = KEXEC_INITRAMFS_CHECK; else if (strcmp(args[0].from, "POLICY_CHECK") == 0) entry->func = POLICY_CHECK; + else if (strcmp(args[0].from, "KEXEC_CMDLINE") == 0) + entry->func = KEXEC_CMDLINE; else result = -EINVAL; if (!result) -- 2.19.1 ^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH V9 1/3] IMA:Define a new hook to measure the kexec boot command line arguments 2019-06-17 18:37 ` [PATCH V9 1/3] IMA:Define a new hook to measure the kexec boot command line arguments Prakhar Srivastava @ 2019-06-19 17:46 ` prakhar srivastava 0 siblings, 0 replies; 9+ messages in thread From: prakhar srivastava @ 2019-06-19 17:46 UTC (permalink / raw) To: linux-integrity, linux-security-module, linux-kernel Cc: Mimi Zohar, Roberto Sassu On Mon, Jun 17, 2019 at 11:37 AM Prakhar Srivastava <prsriva02@gmail.com> wrote: > > Currently during soft reboot(kexec_file_load) boot command line > arguments are not measured. Define hooks needed to measure kexec > command line arguments during soft reboot(kexec_file_load). > > - A new ima hook ima_kexec_cmdline is defined to be called by the > kexec code. > - A new function process_buffer_measurement is defined to measure > the buffer hash into the IMA measurement list. > - A new func policy KEXEC_CMDLINE is defined to control the > measurement.[Suggested by Mimi] > > Signed-off-by: Prakhar Srivastava <prsriva02@gmail.com> > --- > Documentation/ABI/testing/ima_policy | 1 + > include/linux/ima.h | 2 + > security/integrity/ima/ima.h | 1 + > security/integrity/ima/ima_api.c | 1 + > security/integrity/ima/ima_main.c | 74 ++++++++++++++++++++++++++++ > security/integrity/ima/ima_policy.c | 7 +++ > 6 files changed, 86 insertions(+) > > diff --git a/Documentation/ABI/testing/ima_policy b/Documentation/ABI/testing/ima_policy > index b383c1763610..fc376a323908 100644 > --- a/Documentation/ABI/testing/ima_policy > +++ b/Documentation/ABI/testing/ima_policy > @@ -28,6 +28,7 @@ Description: > base: func:= [BPRM_CHECK][MMAP_CHECK][CREDS_CHECK][FILE_CHECK][MODULE_CHECK] > [FIRMWARE_CHECK] > [KEXEC_KERNEL_CHECK] [KEXEC_INITRAMFS_CHECK] > + [KEXEC_CMDLINE] > mask:= [[^]MAY_READ] [[^]MAY_WRITE] [[^]MAY_APPEND] > [[^]MAY_EXEC] > fsmagic:= hex value > diff --git a/include/linux/ima.h b/include/linux/ima.h > index fd9f7cf4cdf5..b42f5a006042 100644 > --- a/include/linux/ima.h > +++ b/include/linux/ima.h > @@ -26,6 +26,7 @@ extern int ima_read_file(struct file *file, enum kernel_read_file_id id); > extern int ima_post_read_file(struct file *file, void *buf, loff_t size, > enum kernel_read_file_id id); > extern void ima_post_path_mknod(struct dentry *dentry); > +extern void ima_kexec_cmdline(const void *buf, int size); > > #ifdef CONFIG_IMA_KEXEC > extern void ima_add_kexec_buffer(struct kimage *image); > @@ -92,6 +93,7 @@ static inline void ima_post_path_mknod(struct dentry *dentry) > return; > } > > +static inline void ima_kexec_cmdline(const void *buf, int size) {} > #endif /* CONFIG_IMA */ > > #ifndef CONFIG_IMA_KEXEC > diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h > index 18b48a6d0b80..a4ad1270bffa 100644 > --- a/security/integrity/ima/ima.h > +++ b/security/integrity/ima/ima.h > @@ -185,6 +185,7 @@ static inline unsigned long ima_hash_key(u8 *digest) > hook(KEXEC_KERNEL_CHECK) \ > hook(KEXEC_INITRAMFS_CHECK) \ > hook(POLICY_CHECK) \ > + hook(KEXEC_CMDLINE) \ > hook(MAX_CHECK) > #define __ima_hook_enumify(ENUM) ENUM, > > diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c > index 78eb11c7ac07..ea7d8cbf712f 100644 > --- a/security/integrity/ima/ima_api.c > +++ b/security/integrity/ima/ima_api.c > @@ -176,6 +176,7 @@ void ima_add_violation(struct file *file, const unsigned char *filename, > * subj=, obj=, type=, func=, mask=, fsmagic= > * subj,obj, and type: are LSM specific. > * func: FILE_CHECK | BPRM_CHECK | CREDS_CHECK | MMAP_CHECK | MODULE_CHECK > + * | KEXEC_CMDLINE > * mask: contains the permission mask > * fsmagic: hex value > * > diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c > index af341a80118f..1e233417a7af 100644 > --- a/security/integrity/ima/ima_main.c > +++ b/security/integrity/ima/ima_main.c > @@ -605,6 +605,80 @@ int ima_load_data(enum kernel_load_data_id id) > return 0; > } > > +/* > + * process_buffer_measurement - Measure the buffer to ima log. > + * @buf: pointer to the buffer that needs to be added to the log. > + * @size: size of buffer(in bytes). > + * @eventname: event name to be used for the buffer entry. > + * @cred: a pointer to a credentials structure for user validation. > + * @secid: the secid of the task to be validated. > + * > + * Based on policy, the buffer is measured into the ima log. > + */ > +static void process_buffer_measurement(const void *buf, int size, > + const char *eventname, > + const struct cred *cred, u32 secid) > +{ > + int ret = 0; > + struct ima_template_entry *entry = NULL; > + struct integrity_iint_cache iint = {}; > + struct ima_event_data event_data = {.iint = &iint }; > + struct ima_template_desc *template_desc = NULL; > + struct { > + struct ima_digest_data hdr; > + char digest[IMA_MAX_DIGEST_SIZE]; > + } hash = {}; > + int violation = 0; > + int pcr = CONFIG_IMA_MEASURE_PCR_IDX; > + int action = 0; > + > + action = ima_get_action(NULL, cred, secid, 0, KEXEC_CMDLINE, &pcr, > + &template_desc); > + if (!(action & IMA_MEASURE)) > + goto out; > + > + event_data.filename = eventname; > + > + iint.ima_hash = &hash.hdr; > + iint.ima_hash->algo = ima_hash_algo; > + iint.ima_hash->length = hash_digest_size[ima_hash_algo]; > + > + ret = ima_calc_buffer_hash(buf, size, iint.ima_hash); > + if (ret < 0) > + goto out; > + > + ret = ima_alloc_init_template(&event_data, &entry, template_desc); > + if (ret < 0) > + goto out; > + > + if (action & IMA_MEASURE) > + ret = ima_store_template(entry, violation, NULL, buf, pcr); > + > + if (ret < 0) > + ima_free_template_entry(entry); > + > +out: > + return; > +} > + > +/** > + * ima_kexec_cmdline - measure kexec cmdline boot args > + * @buf: pointer to buffer > + * @size: size of buffer > + * > + * Buffers can only be measured, not appraised. > + */ > +void ima_kexec_cmdline(const void *buf, int size) > +{ > + u32 secid; > + > + if (buf && size != 0) { > + security_task_getsecid(current, &secid); > + process_buffer_measurement(buf, size, "kexec-cmdline", > + current_cred(), secid); > + } > +} > + > static int __init init_ima(void) > { > int error; > diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c > index fd9b01881d17..4e8bb7eecd08 100644 > --- a/security/integrity/ima/ima_policy.c > +++ b/security/integrity/ima/ima_policy.c > @@ -292,6 +292,11 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode, > { > int i; > > + if (func == KEXEC_CMDLINE) { > + if ((rule->flags & IMA_FUNC) && (rule->func == func)) > + return true; > + return false; > + } > if ((rule->flags & IMA_FUNC) && > (rule->func != func && func != POST_SETATTR)) > return false; > @@ -880,6 +885,8 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) > entry->func = KEXEC_INITRAMFS_CHECK; > else if (strcmp(args[0].from, "POLICY_CHECK") == 0) > entry->func = POLICY_CHECK; > + else if (strcmp(args[0].from, "KEXEC_CMDLINE") == 0) > + entry->func = KEXEC_CMDLINE; > else > result = -EINVAL; > if (!result) > -- > 2.19.1 > Hi Mimi, Can you Ack this patch? I want to make sure this looks okay to you. Thanks, Prakhar Srivastava ^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH V9 2/3] IMA:Define a new template field buf 2019-06-17 18:37 [PATCH V8 0/3] Add support for measuring the boot command line during kexec_file_load Prakhar Srivastava 2019-06-17 18:37 ` [PATCH V9 1/3] IMA:Define a new hook to measure the kexec boot command line arguments Prakhar Srivastava @ 2019-06-17 18:37 ` Prakhar Srivastava 2019-06-17 18:37 ` [PATCH V9 3/3] KEXEC:Call ima_kexec_cmdline to measure the boot command line args Prakhar Srivastava 2 siblings, 0 replies; 9+ messages in thread From: Prakhar Srivastava @ 2019-06-17 18:37 UTC (permalink / raw) To: linux-integrity, linux-security-module, linux-kernel Cc: zohar, roberto.sassu, Prakhar Srivastava A buffer(kexec boot command line arguments) measured into IMA measuremnt list cannot be appraised, without already being aware of the buffer contents. Since hashes are non-reversible, raw buffer is needed for validation or regenerating hash for appraisal/attestation. Add support to store/read the buffer contents in HEX. The kexec cmdline hash is stored in the "d-ng" field of the template data,it can be verified using sudo cat /sys/kernel/security/integrity/ima/ascii_runtime_measurements | grep kexec-cmdline | cut -d' ' -f 6 | xxd -r -p | sha256sum - Add two new fields to ima_event_data to hold the buf and buf_len [Suggested by Roberto] - Add a new temaplte field 'buf' to be used to store/read the buffer data.[Suggested by Mimi] - Updated process_buffer_meaurement to add the buffer to ima_event_data. process_buffer_measurement added in "Define a new IMA hook to measure the boot command line arguments" - Add a new template policy name ima-buf to represent 'd-ng|n-ng|buf' Signed-off-by: Prakhar Srivastava <prsriva02@gmail.com> Reviewed-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: James Morris <jamorris@linux.microsoft.com> --- Documentation/security/IMA-templates.rst | 7 ++++--- security/integrity/ima/ima.h | 2 ++ security/integrity/ima/ima_api.c | 4 ++-- security/integrity/ima/ima_init.c | 2 +- security/integrity/ima/ima_main.c | 2 ++ security/integrity/ima/ima_template.c | 3 +++ security/integrity/ima/ima_template_lib.c | 21 +++++++++++++++++++++ security/integrity/ima/ima_template_lib.h | 4 ++++ 8 files changed, 39 insertions(+), 6 deletions(-) diff --git a/Documentation/security/IMA-templates.rst b/Documentation/security/IMA-templates.rst index 2cd0e273cc9a..fccdbbc984f5 100644 --- a/Documentation/security/IMA-templates.rst +++ b/Documentation/security/IMA-templates.rst @@ -69,14 +69,15 @@ descriptors by adding their identifier to the format string algorithm (field format: [<hash algo>:]digest, where the digest prefix is shown only if the hash algorithm is not SHA1 or MD5); - 'n-ng': the name of the event, without size limitations; - - 'sig': the file signature. - + - 'sig': the file signature; + - 'buf': the buffer data that was used to generate the hash without size limitations; Below, there is the list of defined template descriptors: - "ima": its format is ``d|n``; - "ima-ng" (default): its format is ``d-ng|n-ng``; - - "ima-sig": its format is ``d-ng|n-ng|sig``. + - "ima-sig": its format is ``d-ng|n-ng|sig``; + - "ima-buf": its format is ``d-ng|n-ng|buf``; diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index a4ad1270bffa..16110180545c 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -65,6 +65,8 @@ struct ima_event_data { struct evm_ima_xattr_data *xattr_value; int xattr_len; const char *violation; + const void *buf; + int buf_len; }; /* IMA template field data definition */ diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c index ea7d8cbf712f..83ca99d65e4b 100644 --- a/security/integrity/ima/ima_api.c +++ b/security/integrity/ima/ima_api.c @@ -140,7 +140,7 @@ void ima_add_violation(struct file *file, const unsigned char *filename, struct ima_template_entry *entry; struct inode *inode = file_inode(file); struct ima_event_data event_data = {iint, file, filename, NULL, 0, - cause}; + cause, NULL, 0}; int violation = 1; int result; @@ -296,7 +296,7 @@ void ima_store_measurement(struct integrity_iint_cache *iint, struct inode *inode = file_inode(file); struct ima_template_entry *entry; struct ima_event_data event_data = {iint, file, filename, xattr_value, - xattr_len, NULL}; + xattr_len, NULL, NULL, 0}; int violation = 0; if (iint->measured_pcrs & (0x1 << pcr)) diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c index 993d0f1915ff..c8591406c0e2 100644 --- a/security/integrity/ima/ima_init.c +++ b/security/integrity/ima/ima_init.c @@ -50,7 +50,7 @@ static int __init ima_add_boot_aggregate(void) struct ima_template_entry *entry; struct integrity_iint_cache tmp_iint, *iint = &tmp_iint; struct ima_event_data event_data = {iint, NULL, boot_aggregate_name, - NULL, 0, NULL}; + NULL, 0, NULL, NULL, 0}; int result = -ENOMEM; int violation = 0; struct { diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 1e233417a7af..84b321ac1ad3 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -638,6 +638,8 @@ static void process_buffer_measurement(const void *buf, int size, goto out; event_data.filename = eventname; + event_data.buf = buf; + event_data.buf_len = size; iint.ima_hash = &hash.hdr; iint.ima_hash->algo = ima_hash_algo; diff --git a/security/integrity/ima/ima_template.c b/security/integrity/ima/ima_template.c index e6e892f31cbd..632f314c0e5a 100644 --- a/security/integrity/ima/ima_template.c +++ b/security/integrity/ima/ima_template.c @@ -26,6 +26,7 @@ static struct ima_template_desc builtin_templates[] = { {.name = IMA_TEMPLATE_IMA_NAME, .fmt = IMA_TEMPLATE_IMA_FMT}, {.name = "ima-ng", .fmt = "d-ng|n-ng"}, {.name = "ima-sig", .fmt = "d-ng|n-ng|sig"}, + {.name = "ima-buf", .fmt = "d-ng|n-ng|buf"}, {.name = "", .fmt = ""}, /* placeholder for a custom format */ }; @@ -43,6 +44,8 @@ static const struct ima_template_field supported_fields[] = { .field_show = ima_show_template_string}, {.field_id = "sig", .field_init = ima_eventsig_init, .field_show = ima_show_template_sig}, + {.field_id = "buf", .field_init = ima_eventbuf_init, + .field_show = ima_show_template_buf}, }; #define MAX_TEMPLATE_NAME_LEN 15 diff --git a/security/integrity/ima/ima_template_lib.c b/security/integrity/ima/ima_template_lib.c index 513b457ae900..baf4de45c5aa 100644 --- a/security/integrity/ima/ima_template_lib.c +++ b/security/integrity/ima/ima_template_lib.c @@ -162,6 +162,12 @@ void ima_show_template_sig(struct seq_file *m, enum ima_show_type show, ima_show_template_field_data(m, show, DATA_FMT_HEX, field_data); } +void ima_show_template_buf(struct seq_file *m, enum ima_show_type show, + struct ima_field_data *field_data) +{ + ima_show_template_field_data(m, show, DATA_FMT_HEX, field_data); +} + /** * ima_parse_buf() - Parses lengths and data from an input buffer * @bufstartp: Buffer start address. @@ -389,3 +395,18 @@ int ima_eventsig_init(struct ima_event_data *event_data, return ima_write_template_field_data(xattr_value, event_data->xattr_len, DATA_FMT_HEX, field_data); } + +/* + * ima_eventbuf_init - include the buffer(kexec-cmldine) as part of the + * template data. + */ +int ima_eventbuf_init(struct ima_event_data *event_data, + struct ima_field_data *field_data) +{ + if ((!event_data->buf) || (event_data->buf_len == 0)) + return 0; + + return ima_write_template_field_data(event_data->buf, + event_data->buf_len, DATA_FMT_HEX, + field_data); +} diff --git a/security/integrity/ima/ima_template_lib.h b/security/integrity/ima/ima_template_lib.h index 6a3d8b831deb..12f1a8578b31 100644 --- a/security/integrity/ima/ima_template_lib.h +++ b/security/integrity/ima/ima_template_lib.h @@ -29,6 +29,8 @@ void ima_show_template_string(struct seq_file *m, enum ima_show_type show, struct ima_field_data *field_data); void ima_show_template_sig(struct seq_file *m, enum ima_show_type show, struct ima_field_data *field_data); +void ima_show_template_buf(struct seq_file *m, enum ima_show_type show, + struct ima_field_data *field_data); int ima_parse_buf(void *bufstartp, void *bufendp, void **bufcurp, int maxfields, struct ima_field_data *fields, int *curfields, unsigned long *len_mask, int enforce_mask, char *bufname); @@ -42,4 +44,6 @@ int ima_eventname_ng_init(struct ima_event_data *event_data, struct ima_field_data *field_data); int ima_eventsig_init(struct ima_event_data *event_data, struct ima_field_data *field_data); +int ima_eventbuf_init(struct ima_event_data *event_data, + struct ima_field_data *field_data); #endif /* __LINUX_IMA_TEMPLATE_LIB_H */ -- 2.19.1 ^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH V9 3/3] KEXEC:Call ima_kexec_cmdline to measure the boot command line args 2019-06-17 18:37 [PATCH V8 0/3] Add support for measuring the boot command line during kexec_file_load Prakhar Srivastava 2019-06-17 18:37 ` [PATCH V9 1/3] IMA:Define a new hook to measure the kexec boot command line arguments Prakhar Srivastava 2019-06-17 18:37 ` [PATCH V9 2/3] IMA:Define a new template field buf Prakhar Srivastava @ 2019-06-17 18:37 ` Prakhar Srivastava 2 siblings, 0 replies; 9+ messages in thread From: Prakhar Srivastava @ 2019-06-17 18:37 UTC (permalink / raw) To: linux-integrity, linux-security-module, linux-kernel Cc: zohar, roberto.sassu, Prakhar Srivastava During soft reboot(kexec_file_load) boot command line arguments are not measured. Call ima hook ima_kexec_cmdline to measure the boot command line arguments into IMA measurement list. - call ima_kexec_cmdline from kexec_file_load. - move the call ima_add_kexec_buffer after the cmdline args have been measured. Signed-off-by: Prakhar Srivastava <prsriva02@gmail.com> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Acked-by: Dave Young <dyoung@redhat.com> --- kernel/kexec_file.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index 072b6ee55e3f..b0c724e5d86c 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -198,9 +198,6 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, return ret; image->kernel_buf_len = size; - /* IMA needs to pass the measurement list to the next kernel. */ - ima_add_kexec_buffer(image); - /* Call arch image probe handlers */ ret = arch_kexec_kernel_image_probe(image, image->kernel_buf, image->kernel_buf_len); @@ -241,8 +238,14 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, ret = -EINVAL; goto out; } + + ima_kexec_cmdline(image->cmdline_buf, + image->cmdline_buf_len - 1); } + /* IMA needs to pass the measurement list to the next kernel. */ + ima_add_kexec_buffer(image); + /* Call arch image load handlers */ ldata = arch_kexec_kernel_image_load(image); -- 2.19.1 ^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH V8 0/3] Add support for measuring the boot command line during kexec_file_load @ 2019-06-17 18:35 Prakhar Srivastava 0 siblings, 0 replies; 9+ messages in thread From: Prakhar Srivastava @ 2019-06-17 18:35 UTC (permalink / raw) To: linux-integrity, linux-security-module, linux-kernel Cc: zohar, roberto.sassu, Prakhar Srivastava The kexec boot command line arguments are not currently being measured. Currently during soft reboot(kexec) - the PCRS are not reset - the command line arguments used for the next kernel are not measured. This gives the impression to the secure boot attestation that a cold boot took place. For secure boot attestation, it is necessary to measure the kernel command line. For cold boot, the boot loader can be enhanced to measure these parameters. (https://mjg59.dreamwidth.org/48897.html) This patch set aims to address measuring the boot command line during soft reboot(kexec_file_load). To achive the above the patch series does the following -Add a new ima hook: ima_kexec_cmdline which measures the cmdline args into the ima log, behind a new ima policy entry KEXEC_CMDLINE. The kexec cmdline hash is stored in the "d-ng" field of the template data. -Since the cmldine args cannot be appraised, a new template field(buf) is added. The template field contains the buffer passed(cmldine args), which can be used to appraise/attest at a later stage. The kexec cmdline buffer is stored as HEX in the buf field of the event_data. -Call the ima_kexec_cmdline(...) hook from kexec_file_load call. The ima logs need to be carried over to the next kernel, which will be followed up by other patchsets for x86_64 and arm64. The kexec cmdline hash is stored in the "d-ng" field of the template data. and can be verified using sudo cat /sys/kernel/security/integrity/ima/ascii_runtime_measurements | grep kexec-cmdline | cut -d' ' -f 6 | xxd -r -p | sha256sum Changelog: V9(since V8): - code cleanup V8(since V7): - added a new ima template name "ima-buf" - code cleanup V7: - rebased to next-queued-testing https://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity.git/log/?h=next-queued-testing V6: -add a new ima hook and policy to measure the cmdline args(ima_kexec_cmdline) -add a new template field buf to contain the buffer measured. [suggested by Mimi Zohar] add new fields to ima_event_data to store/read buffer data. [suggested by Roberto] -call ima_kexec_cmdline from kexec_file_load path v5: -add a new ima hook and policy to measure the cmdline args(ima_kexec_cmdline) -add a new template field buf to contain the buffer measured. [suggested by Mimi Zohar] -call ima_kexec_cmdline from kexec_file_load path v4: - per feedback from LSM community, removed the LSM hook and renamed the IMA policy to KEXEC_CMDLINE v3: (rebase changes to next-general) - Add policy checks for buffer[suggested by Mimi Zohar] - use the IMA_XATTR to add buffer - Add kexec_cmdline used for kexec file load - Add an LSM hook to allow usage by other LSM.[suggestd by Mimi Zohar] v2: - Add policy checks for buffer[suggested by Mimi Zohar] - Add an LSM hook to allow usage by other LSM.[suggestd by Mimi Zohar] - use the IMA_XATTR to add buffer instead of sig template v1: -Add kconfigs to control the ima_buffer_check -measure the cmdline args suffixed with the kernel file name -add the buffer to the template sig field. Prakhar Srivastava (3): Add a new ima hook ima_kexec_cmdline to measure cmdline args add a new ima template field buf call ima_kexec_cmdline to measure the cmdline args Documentation/ABI/testing/ima_policy | 1 + Documentation/security/IMA-templates.rst | 2 +- include/linux/ima.h | 2 + kernel/kexec_file.c | 8 ++- security/integrity/ima/ima.h | 3 + security/integrity/ima/ima_api.c | 5 +- security/integrity/ima/ima_init.c | 2 +- security/integrity/ima/ima_main.c | 80 +++++++++++++++++++++++ security/integrity/ima/ima_policy.c | 9 +++ security/integrity/ima/ima_template.c | 2 + security/integrity/ima/ima_template_lib.c | 20 ++++++ security/integrity/ima/ima_template_lib.h | 4 ++ 12 files changed, 131 insertions(+), 7 deletions(-) -- 2.17.1 ^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH V8 0/3] Add support for measuring the boot command line during kexec_file_load @ 2019-06-12 22:15 Prakhar Srivastava 2019-06-13 20:48 ` Mimi Zohar 0 siblings, 1 reply; 9+ messages in thread From: Prakhar Srivastava @ 2019-06-12 22:15 UTC (permalink / raw) To: linux-integrity, linux-security-module, linux-kernel Cc: zohar, roberto.sassu, vgoyal, Prakhar Srivastava The kexec boot command line arguments are not currently being measured. Currently during soft reboot(kexec) - the PCRS are not reset - the command line arguments used for the next kernel are not measured. This gives the impression to the secure boot attestation that a cold boot took place. For secure boot attestation, it is necessary to measure the kernel command line. For cold boot, the boot loader can be enhanced to measure these parameters. (https://mjg59.dreamwidth.org/48897.html) This patch set aims to address measuring the boot command line during soft reboot(kexec_file_load). To achive the above the patch series does the following -Add a new ima hook: ima_kexec_cmdline which measures the cmdline args into the ima log, behind a new ima policy entry KEXEC_CMDLINE. The kexec cmdline hash is stored in the "d-ng" field of the template data. -Since the cmldine args cannot be appraised, a new template field(buf) is added. The template field contains the buffer passed(cmldine args), which can be used to appraise/attest at a later stage. The kexec cmdline buffer is stored as HEX in the buf field of the event_data. -Call the ima_kexec_cmdline(...) hook from kexec_file_load call. The ima logs need to be carried over to the next kernel, which will be followed up by other patchsets for x86_64 and arm64. The kexec cmdline hash is stored in the "d-ng" field of the template data. and can be verified using sudo cat /sys/kernel/security/integrity/ima/ascii_runtime_measurements | grep kexec-cmdline | cut -d' ' -f 6 | xxd -r -p | sha256sum Changelog: V8(since V7): - added a new ima template name "ima-buf" - code cleanup V7: - rebased to next-queued-testing https://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity.git/log/?h=next-queued-testing V6: -add a new ima hook and policy to measure the cmdline args(ima_kexec_cmdline) -add a new template field buf to contain the buffer measured. [suggested by Mimi Zohar] add new fields to ima_event_data to store/read buffer data. [suggested by Roberto] -call ima_kexec_cmdline from kexec_file_load path v5: -add a new ima hook and policy to measure the cmdline args(ima_kexec_cmdline) -add a new template field buf to contain the buffer measured. [suggested by Mimi Zohar] -call ima_kexec_cmdline from kexec_file_load path v4: - per feedback from LSM community, removed the LSM hook and renamed the IMA policy to KEXEC_CMDLINE v3: (rebase changes to next-general) - Add policy checks for buffer[suggested by Mimi Zohar] - use the IMA_XATTR to add buffer - Add kexec_cmdline used for kexec file load - Add an LSM hook to allow usage by other LSM.[suggestd by Mimi Zohar] v2: - Add policy checks for buffer[suggested by Mimi Zohar] - Add an LSM hook to allow usage by other LSM.[suggestd by Mimi Zohar] - use the IMA_XATTR to add buffer instead of sig template v1: -Add kconfigs to control the ima_buffer_check -measure the cmdline args suffixed with the kernel file name -add the buffer to the template sig field. Prakhar Srivastava (3): Add a new ima hook ima_kexec_cmdline to measure cmdline args add a new ima template field buf call ima_kexec_cmdline to measure the cmdline args Documentation/ABI/testing/ima_policy | 1 + Documentation/security/IMA-templates.rst | 2 +- include/linux/ima.h | 2 + kernel/kexec_file.c | 8 ++- security/integrity/ima/ima.h | 3 + security/integrity/ima/ima_api.c | 5 +- security/integrity/ima/ima_init.c | 2 +- security/integrity/ima/ima_main.c | 80 +++++++++++++++++++++++ security/integrity/ima/ima_policy.c | 9 +++ security/integrity/ima/ima_template.c | 2 + security/integrity/ima/ima_template_lib.c | 20 ++++++ security/integrity/ima/ima_template_lib.h | 4 ++ 12 files changed, 131 insertions(+), 7 deletions(-) -- 2.17.1 ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH V8 0/3] Add support for measuring the boot command line during kexec_file_load 2019-06-12 22:15 Prakhar Srivastava @ 2019-06-13 20:48 ` Mimi Zohar 2019-06-14 17:39 ` prakhar srivastava 0 siblings, 1 reply; 9+ messages in thread From: Mimi Zohar @ 2019-06-13 20:48 UTC (permalink / raw) To: Prakhar Srivastava, linux-integrity, linux-security-module, linux-kernel Cc: roberto.sassu, vgoyal On Wed, 2019-06-12 at 15:15 -0700, Prakhar Srivastava wrote: > The kexec cmdline hash is stored in the "d-ng" field of the template data. > and can be verified using > sudo cat /sys/kernel/security/integrity/ima/ascii_runtime_measurements | > grep kexec-cmdline | cut -d' ' -f 6 | xxd -r -p | sha256sum This information should also be included in one of the patches. Mimi ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH V8 0/3] Add support for measuring the boot command line during kexec_file_load 2019-06-13 20:48 ` Mimi Zohar @ 2019-06-14 17:39 ` prakhar srivastava 0 siblings, 0 replies; 9+ messages in thread From: prakhar srivastava @ 2019-06-14 17:39 UTC (permalink / raw) To: Mimi Zohar Cc: linux-integrity, linux-security-module, linux-kernel, Roberto Sassu, vgoyal On Thu, Jun 13, 2019 at 1:48 PM Mimi Zohar <zohar@linux.ibm.com> wrote: > > On Wed, 2019-06-12 at 15:15 -0700, Prakhar Srivastava wrote: > > > The kexec cmdline hash is stored in the "d-ng" field of the template data. > > and can be verified using > > sudo cat /sys/kernel/security/integrity/ima/ascii_runtime_measurements | > > grep kexec-cmdline | cut -d' ' -f 6 | xxd -r -p | sha256sum > > This information should also be included in one of the patches. > Noted. I will add this to the 2/3 patch, since that the one that adds the template. - Thanks, Prakhar Srivastava > Mimi > ^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2019-06-19 17:46 UTC | newest] Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2019-06-17 18:37 [PATCH V8 0/3] Add support for measuring the boot command line during kexec_file_load Prakhar Srivastava 2019-06-17 18:37 ` [PATCH V9 1/3] IMA:Define a new hook to measure the kexec boot command line arguments Prakhar Srivastava 2019-06-19 17:46 ` prakhar srivastava 2019-06-17 18:37 ` [PATCH V9 2/3] IMA:Define a new template field buf Prakhar Srivastava 2019-06-17 18:37 ` [PATCH V9 3/3] KEXEC:Call ima_kexec_cmdline to measure the boot command line args Prakhar Srivastava -- strict thread matches above, loose matches on Subject: below -- 2019-06-17 18:35 [PATCH V8 0/3] Add support for measuring the boot command line during kexec_file_load Prakhar Srivastava 2019-06-12 22:15 Prakhar Srivastava 2019-06-13 20:48 ` Mimi Zohar 2019-06-14 17:39 ` prakhar srivastava
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