From 75ce9e446109728030c7a29cd4b558c39990a7c3 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Mon, 13 Oct 2014 14:08:39 +0200 Subject: [PATCH] ima: display template format in meas. list if template name length is zero With the introduction of the 'ima_template_fmt' kernel cmdline parameter, a user can define a new template descriptor with custom format. However, in this case, userspace tools will be unable to parse the measurements list because the new template is unknown. For this reason, this patch modifies the current IMA behavior to display in the list the template format instead of the name (only if the length of the latter is zero) so that a tool can extract needed information if it can handle listed fields. This patch also correctly displays the error log message in ima_init_template() if the selected template cannot be initialized. Changelog: - v3: - check the first byte of 'e->template_desc->name' instead of using strlen() in ima_fs.c (suggested by Mimi Zohar) - v2: - print the template format in ima_init_template(), if the selected template is custom (Roberto Sassu) - v1: - fixed patch description (Roberto Sassu, suggested by Mimi Zohar) - set 'template_name' variable in ima_fs.c only once (Roberto Sassu, suggested by Mimi Zohar) Signed-off-by: Roberto Sassu Signed-off-by: Mimi Zohar --- security/integrity/ima/ima_fs.c | 16 ++++++++++++---- security/integrity/ima/ima_template.c | 4 +++- 2 files changed, 15 insertions(+), 5 deletions(-) diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index 973b5683a92ef..461215e5fd31d 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -118,6 +118,7 @@ static int ima_measurements_show(struct seq_file *m, void *v) /* the list never shrinks, so we don't need a lock here */ struct ima_queue_entry *qe = v; struct ima_template_entry *e; + char *template_name; int namelen; u32 pcr = CONFIG_IMA_MEASURE_PCR_IDX; bool is_ima_template = false; @@ -128,6 +129,9 @@ static int ima_measurements_show(struct seq_file *m, void *v) if (e == NULL) return -1; + template_name = (e->template_desc->name[0] != '\0') ? + e->template_desc->name : e->template_desc->fmt; + /* * 1st: PCRIndex * PCR used is always the same (config option) in @@ -139,14 +143,14 @@ static int ima_measurements_show(struct seq_file *m, void *v) ima_putc(m, e->digest, TPM_DIGEST_SIZE); /* 3rd: template name size */ - namelen = strlen(e->template_desc->name); + namelen = strlen(template_name); ima_putc(m, &namelen, sizeof(namelen)); /* 4th: template name */ - ima_putc(m, e->template_desc->name, namelen); + ima_putc(m, template_name, namelen); /* 5th: template length (except for 'ima' template) */ - if (strcmp(e->template_desc->name, IMA_TEMPLATE_IMA_NAME) == 0) + if (strcmp(template_name, IMA_TEMPLATE_IMA_NAME) == 0) is_ima_template = true; if (!is_ima_template) @@ -200,6 +204,7 @@ static int ima_ascii_measurements_show(struct seq_file *m, void *v) /* the list never shrinks, so we don't need a lock here */ struct ima_queue_entry *qe = v; struct ima_template_entry *e; + char *template_name; int i; /* get entry */ @@ -207,6 +212,9 @@ static int ima_ascii_measurements_show(struct seq_file *m, void *v) if (e == NULL) return -1; + template_name = (e->template_desc->name[0] != '\0') ? + e->template_desc->name : e->template_desc->fmt; + /* 1st: PCR used (config option) */ seq_printf(m, "%2d ", CONFIG_IMA_MEASURE_PCR_IDX); @@ -214,7 +222,7 @@ static int ima_ascii_measurements_show(struct seq_file *m, void *v) ima_print_digest(m, e->digest, TPM_DIGEST_SIZE); /* 3th: template name */ - seq_printf(m, " %s", e->template_desc->name); + seq_printf(m, " %s", template_name); /* 4th: template specific data */ for (i = 0; i < e->template_desc->num_fields; i++) { diff --git a/security/integrity/ima/ima_template.c b/security/integrity/ima/ima_template.c index 1310afc587f31..b7b359ca39ee1 100644 --- a/security/integrity/ima/ima_template.c +++ b/security/integrity/ima/ima_template.c @@ -176,7 +176,9 @@ int __init ima_init_template(void) &(template->fields), &(template->num_fields)); if (result < 0) - pr_err("template %s init failed, result: %d\n", template->name); + pr_err("template %s init failed, result: %d\n", + (strlen(template->name) ? + template->name : template->fmt), result); return result; } -- 2.39.5