Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753981Ab3JUWtA (ORCPT ); Mon, 21 Oct 2013 18:49:00 -0400 Received: from e36.co.us.ibm.com ([32.97.110.154]:41696 "EHLO e36.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752834Ab3JUWni (ORCPT ); Mon, 21 Oct 2013 18:43:38 -0400 From: Mimi Zohar To: linux-security-module@vger.kernel.org Cc: Roberto Sassu , linux-kernel@vger.kernel.org, James Morris , David Howells , Mimi Zohar Subject: [PATCH v2 15/23] ima: define template fields library and new helpers Date: Mon, 21 Oct 2013 18:43:00 -0400 Message-Id: <1382395388-8108-16-git-send-email-zohar@linux.vnet.ibm.com> X-Mailer: git-send-email 1.8.1.4 In-Reply-To: <1382395388-8108-1-git-send-email-zohar@linux.vnet.ibm.com> References: <1382395388-8108-1-git-send-email-zohar@linux.vnet.ibm.com> X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13102122-3532-0000-0000-000002596AFD Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 12421 Lines: 384 From: Roberto Sassu This patch defines a library containing two initial template fields, inode digest (d) and file name (n), the 'ima' template descriptor, whose format is 'd|n', and two helper functions, ima_write_template_field_data() and ima_show_template_field_data(). Changelog: - replace ima_eventname_init() parameter NULL checking with BUG_ON. (suggested by Mimi) - include "new template fields for inode digest (d) and file name (n)" definitions to fix a compiler warning. - Mimi - unnecessary to prefix static function names with 'ima_'. remove prefix to resolve Lindent formatting changes. - Mimi - abbreviated/removed inline comments - Mimi - always send the template field length - Mimi Signed-off-by: Roberto Sassu Signed-off-by: Mimi Zohar --- security/integrity/ima/Makefile | 2 +- security/integrity/ima/ima.h | 5 + security/integrity/ima/ima_fs.c | 4 +- security/integrity/ima/ima_template.c | 15 ++- security/integrity/ima/ima_template_lib.c | 193 ++++++++++++++++++++++++++++++ security/integrity/ima/ima_template_lib.h | 31 +++++ 6 files changed, 242 insertions(+), 8 deletions(-) create mode 100644 security/integrity/ima/ima_template_lib.c create mode 100644 security/integrity/ima/ima_template_lib.h diff --git a/security/integrity/ima/Makefile b/security/integrity/ima/Makefile index 7fe4ae3..d79263d 100644 --- a/security/integrity/ima/Makefile +++ b/security/integrity/ima/Makefile @@ -6,5 +6,5 @@ obj-$(CONFIG_IMA) += ima.o ima-y := ima_fs.o ima_queue.o ima_init.o ima_main.o ima_crypto.o ima_api.o \ - ima_policy.o ima_template.o + ima_policy.o ima_template.o ima_template_lib.o ima-$(CONFIG_IMA_APPRAISE) += ima_appraise.o diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index c85718f..e1f081d 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -39,6 +39,9 @@ enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 }; #define IMA_TEMPLATE_FIELD_ID_MAX_LEN 16 #define IMA_TEMPLATE_NUM_FIELDS_MAX 15 +#define IMA_TEMPLATE_IMA_NAME "ima" +#define IMA_TEMPLATE_IMA_FMT "d|n" + /* set during initialization */ extern int ima_initialized; extern int ima_used_chip; @@ -105,6 +108,8 @@ int __init ima_calc_boot_aggregate(struct ima_digest_data *hash); void ima_add_violation(struct file *file, const unsigned char *filename, const char *op, const char *cause); int ima_init_crypto(void); +void ima_putc(struct seq_file *m, void *data, int datalen); +void ima_print_digest(struct seq_file *m, u8 *digest, int size); int ima_init_template(void); diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index c35cfb5..414862e 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -99,7 +99,7 @@ static void ima_measurements_stop(struct seq_file *m, void *v) { } -static void ima_putc(struct seq_file *m, void *data, int datalen) +void ima_putc(struct seq_file *m, void *data, int datalen) { while (datalen--) seq_putc(m, *(char *)data++); @@ -167,7 +167,7 @@ static const struct file_operations ima_measurements_ops = { .release = seq_release, }; -static void ima_print_digest(struct seq_file *m, u8 *digest, int size) +void ima_print_digest(struct seq_file *m, u8 *digest, int size) { int i; diff --git a/security/integrity/ima/ima_template.c b/security/integrity/ima/ima_template.c index 7e86783..8100422 100644 --- a/security/integrity/ima/ima_template.c +++ b/security/integrity/ima/ima_template.c @@ -13,15 +13,20 @@ * Helpers to manage template descriptors. */ #include "ima.h" +#include "ima_template_lib.h" static struct ima_template_desc defined_templates[] = { + {.name = IMA_TEMPLATE_IMA_NAME,.fmt = IMA_TEMPLATE_IMA_FMT}, }; static struct ima_template_field supported_fields[] = { + {.field_id = "d",.field_init = ima_eventdigest_init, + .field_show = ima_show_template_digest}, + {.field_id = "n",.field_init = ima_eventname_init, + .field_show = ima_show_template_string}, }; -static struct ima_template_field *ima_lookup_template_field( - const char *field_id) +static struct ima_template_field *lookup_template_field(const char *field_id) { int i; @@ -32,7 +37,7 @@ static struct ima_template_field *ima_lookup_template_field( return NULL; } -static int ima_template_fmt_size(char *template_fmt) +static int template_fmt_size(char *template_fmt) { char c; int template_fmt_len = strlen(template_fmt); @@ -53,7 +58,7 @@ static int template_desc_init_fields(char *template_fmt, int *num_fields) { char *c, *template_fmt_ptr = template_fmt; - int template_num_fields = ima_template_fmt_size(template_fmt); + int template_num_fields = template_fmt_size(template_fmt); int i, result = 0; if (template_num_fields > IMA_TEMPLATE_NUM_FIELDS_MAX) @@ -66,7 +71,7 @@ static int template_desc_init_fields(char *template_fmt, } for (i = 0; (c = strsep(&template_fmt_ptr, "|")) != NULL && i < template_num_fields; i++) { - struct ima_template_field *f = ima_lookup_template_field(c); + struct ima_template_field *f = lookup_template_field(c); if (!f) { result = -ENOENT; diff --git a/security/integrity/ima/ima_template_lib.c b/security/integrity/ima/ima_template_lib.c new file mode 100644 index 0000000..e13fc7c --- /dev/null +++ b/security/integrity/ima/ima_template_lib.c @@ -0,0 +1,193 @@ +/* + * Copyright (C) 2013 Politecnico di Torino, Italy + * TORSEC group -- http://security.polito.it + * + * Author: Roberto Sassu + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + * + * File: ima_template_lib.c + * Library of supported template fields. + */ +#include "ima_template_lib.h" + +enum data_formats { DATA_FMT_DIGEST = 0, DATA_FMT_EVENT_NAME, DATA_FMT_STRING }; +static int ima_write_template_field_data(const void *data, const u32 datalen, + enum data_formats datafmt, + struct ima_field_data *field_data) +{ + u8 *buf, *buf_ptr; + u32 buflen; + + switch (datafmt) { + case DATA_FMT_EVENT_NAME: + buflen = IMA_EVENT_NAME_LEN_MAX + 1; + break; + case DATA_FMT_STRING: + buflen = datalen + 1; + break; + default: + buflen = datalen; + } + + buf = kzalloc(buflen, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + memcpy(buf, data, datalen); + + /* + * Replace all space characters with underscore for event names and + * strings. This avoid that, during the parsing of a measurements list, + * filenames with spaces or that end with the suffix ' (deleted)' are + * split into multiple template fields (the space is the delimitator + * character for measurements lists in ASCII format). + */ + if (datafmt == DATA_FMT_EVENT_NAME || datafmt == DATA_FMT_STRING) { + for (buf_ptr = buf; buf_ptr - buf < datalen; buf_ptr++) + if (*buf_ptr == ' ') + *buf_ptr = '_'; + } + + field_data->data = buf; + field_data->len = buflen; + return 0; +} + +static void ima_show_template_data_ascii(struct seq_file *m, + enum ima_show_type show, + enum data_formats datafmt, + struct ima_field_data *field_data) +{ + switch (datafmt) { + case DATA_FMT_DIGEST: + ima_print_digest(m, field_data->data, field_data->len); + break; + case DATA_FMT_STRING: + seq_printf(m, "%s", field_data->data); + break; + default: + break; + } +} + +static void ima_show_template_data_binary(struct seq_file *m, + enum ima_show_type show, + enum data_formats datafmt, + struct ima_field_data *field_data) +{ + ima_putc(m, &field_data->len, sizeof(u32)); + if (!field_data->len) + return; + ima_putc(m, field_data->data, field_data->len); +} + +static void ima_show_template_field_data(struct seq_file *m, + enum ima_show_type show, + enum data_formats datafmt, + struct ima_field_data *field_data) +{ + switch (show) { + case IMA_SHOW_ASCII: + ima_show_template_data_ascii(m, show, datafmt, field_data); + break; + case IMA_SHOW_BINARY: + ima_show_template_data_binary(m, show, datafmt, field_data); + break; + default: + break; + } +} + +void ima_show_template_digest(struct seq_file *m, enum ima_show_type show, + struct ima_field_data *field_data) +{ + ima_show_template_field_data(m, show, DATA_FMT_DIGEST, field_data); +} + +void ima_show_template_string(struct seq_file *m, enum ima_show_type show, + struct ima_field_data *field_data) +{ + ima_show_template_field_data(m, show, DATA_FMT_STRING, field_data); +} + +/* + * This function writes the digest of an event. + */ +int ima_eventdigest_init(struct integrity_iint_cache *iint, struct file *file, + const unsigned char *filename, + struct ima_field_data *field_data) +{ + struct { + struct ima_digest_data hdr; + char digest[IMA_MAX_DIGEST_SIZE]; + } hash; + u8 *cur_digest = hash.hdr.digest; + u32 cur_digestsize = IMA_DIGEST_SIZE; + struct inode *inode; + int result; + + memset(&hash, 0, sizeof(hash)); + + if (!iint) /* recording a violation. */ + goto out; + + if (iint->ima_hash->algo == ima_hash_algo) { + cur_digest = iint->ima_hash->digest; + cur_digestsize = iint->ima_hash->length; + goto out; + } + + if (!file) /* missing info to re-calculate the digest */ + return -EINVAL; + + inode = file_inode(file); + hash.hdr.algo = ima_hash_algo; + result = ima_calc_file_hash(file, &hash.hdr); + if (result) { + integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode, + filename, "collect_data", + "failed", result, 0); + return result; + } +out: + return ima_write_template_field_data(cur_digest, cur_digestsize, + DATA_FMT_DIGEST, field_data); +} + +/* + * This function writes the name of an event. + */ +int ima_eventname_init(struct integrity_iint_cache *iint, struct file *file, + const unsigned char *filename, + struct ima_field_data *field_data) +{ + const char *cur_filename = NULL; + u32 cur_filename_len = 0; + + BUG_ON(filename == NULL && file == NULL); + + if (filename) { + cur_filename = filename; + cur_filename_len = strlen(filename); + + if (cur_filename_len <= IMA_EVENT_NAME_LEN_MAX) + goto out; + } + + if (file) { + cur_filename = file->f_dentry->d_name.name; + cur_filename_len = strlen(cur_filename); + } else + /* + * Truncate filename if the latter is too long and + * the file descriptor is not available. + */ + cur_filename_len = IMA_EVENT_NAME_LEN_MAX; +out: + return ima_write_template_field_data(cur_filename, cur_filename_len, + DATA_FMT_EVENT_NAME, field_data); +} diff --git a/security/integrity/ima/ima_template_lib.h b/security/integrity/ima/ima_template_lib.h new file mode 100644 index 0000000..2cecc83 --- /dev/null +++ b/security/integrity/ima/ima_template_lib.h @@ -0,0 +1,31 @@ +/* + * Copyright (C) 2013 Politecnico di Torino, Italy + * TORSEC group -- http://security.polito.it + * + * Author: Roberto Sassu + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + * + * File: ima_template_lib.h + * Header for the library of supported template fields. + */ +#ifndef __LINUX_IMA_TEMPLATE_LIB_H +#define __LINUX_IMA_TEMPLATE_LIB_H + +#include +#include "ima.h" + +void ima_show_template_digest(struct seq_file *m, enum ima_show_type show, + struct ima_field_data *field_data); +void ima_show_template_string(struct seq_file *m, enum ima_show_type show, + struct ima_field_data *field_data); +int ima_eventdigest_init(struct integrity_iint_cache *iint, struct file *file, + const unsigned char *filename, + struct ima_field_data *field_data); +int ima_eventname_init(struct integrity_iint_cache *iint, struct file *file, + const unsigned char *filename, + struct ima_field_data *field_data); +#endif /* __LINUX_IMA_TEMPLATE_LIB_H */ -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/