--- zzzz-none-000/linux-3.10.107/security/integrity/ima/ima_main.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/security/integrity/ima/ima_main.c 2021-02-04 17:41:59.000000000 +0000 @@ -24,6 +24,7 @@ #include #include #include +#include #include "ima.h" @@ -35,11 +36,33 @@ int ima_appraise; #endif -char *ima_hash = "sha1"; +int ima_hash_algo = HASH_ALGO_SHA1; +static int hash_setup_done; + static int __init hash_setup(char *str) { - if (strncmp(str, "md5", 3) == 0) - ima_hash = "md5"; + struct ima_template_desc *template_desc = ima_template_desc_current(); + int i; + + if (hash_setup_done) + return 1; + + if (strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) == 0) { + if (strncmp(str, "sha1", 4) == 0) + ima_hash_algo = HASH_ALGO_SHA1; + else if (strncmp(str, "md5", 3) == 0) + ima_hash_algo = HASH_ALGO_MD5; + goto out; + } + + for (i = 0; i < HASH_ALGO__LAST; i++) { + if (strcmp(str, hash_algo_name[i]) == 0) { + ima_hash_algo = i; + break; + } + } +out: + hash_setup_done = 1; return 1; } __setup("ima_hash=", hash_setup); @@ -48,56 +71,46 @@ * ima_rdwr_violation_check * * Only invalidate the PCR for measured files: - * - Opening a file for write when already open for read, + * - Opening a file for write when already open for read, * results in a time of measure, time of use (ToMToU) error. * - Opening a file for read when already open for write, - * could result in a file measurement error. + * could result in a file measurement error. * */ -static void ima_rdwr_violation_check(struct file *file) +static void ima_rdwr_violation_check(struct file *file, + struct integrity_iint_cache *iint, + int must_measure, + char **pathbuf, + const char **pathname) { - struct dentry *dentry = file->f_path.dentry; - struct inode *inode = dentry->d_inode; + struct inode *inode = file_inode(file); fmode_t mode = file->f_mode; - int must_measure; bool send_tomtou = false, send_writers = false; - char *pathbuf = NULL; - const char *pathname; - - if (!S_ISREG(inode->i_mode) || !ima_initialized) - return; - - mutex_lock(&inode->i_mutex); /* file metadata: permissions, xattr */ if (mode & FMODE_WRITE) { - if (atomic_read(&inode->i_readcount) && IS_IMA(inode)) - send_tomtou = true; - goto out; + if (atomic_read(&inode->i_readcount) && IS_IMA(inode)) { + if (!iint) + iint = integrity_iint_find(inode); + /* IMA_MEASURE is set from reader side */ + if (iint && (iint->flags & IMA_MEASURE)) + send_tomtou = true; + } + } else { + if ((atomic_read(&inode->i_writecount) > 0) && must_measure) + send_writers = true; } - must_measure = ima_must_measure(inode, MAY_READ, FILE_CHECK); - if (!must_measure) - goto out; - - if (atomic_read(&inode->i_writecount) > 0) - send_writers = true; -out: - mutex_unlock(&inode->i_mutex); - if (!send_tomtou && !send_writers) return; - pathname = ima_d_path(&file->f_path, &pathbuf); - if (!pathname || strlen(pathname) > IMA_EVENT_NAME_LEN_MAX) - pathname = dentry->d_name.name; + *pathname = ima_d_path(&file->f_path, pathbuf); if (send_tomtou) - ima_add_violation(inode, pathname, + ima_add_violation(file, *pathname, iint, "invalid_pcr", "ToMToU"); if (send_writers) - ima_add_violation(inode, pathname, + ima_add_violation(file, *pathname, iint, "invalid_pcr", "open_writers"); - kfree(pathbuf); } static void ima_check_last_writer(struct integrity_iint_cache *iint, @@ -109,11 +122,13 @@ return; mutex_lock(&inode->i_mutex); - if (atomic_read(&inode->i_writecount) == 1 && - iint->version != inode->i_version) { - iint->flags &= ~IMA_DONE_MASK; - if (iint->flags & IMA_APPRAISE) - ima_update_xattr(iint, file); + if (atomic_read(&inode->i_writecount) == 1) { + if ((iint->version != inode->i_version) || + (iint->flags & IMA_NEW_FILE)) { + iint->flags &= ~(IMA_DONE_MASK | IMA_NEW_FILE); + if (iint->flags & IMA_APPRAISE) + ima_update_xattr(iint, file); + } } mutex_unlock(&inode->i_mutex); } @@ -129,7 +144,7 @@ struct inode *inode = file_inode(file); struct integrity_iint_cache *iint; - if (!iint_initialized || !S_ISREG(inode->i_mode)) + if (!ima_policy_flag || !S_ISREG(inode->i_mode)) return; iint = integrity_iint_find(inode); @@ -139,16 +154,20 @@ ima_check_last_writer(iint, inode, file); } -static int process_measurement(struct file *file, const char *filename, - int mask, int function) +static int process_measurement(struct file *file, int mask, int function, + int opened) { struct inode *inode = file_inode(file); - struct integrity_iint_cache *iint; + struct integrity_iint_cache *iint = NULL; + struct ima_template_desc *template_desc; char *pathbuf = NULL; const char *pathname = NULL; - int rc = -ENOMEM, action, must_appraise, _func; + int rc = -ENOMEM, action, must_appraise; + struct evm_ima_xattr_data *xattr_value = NULL, **xattr_ptr = NULL; + int xattr_len = 0; + bool violation_check; - if (!ima_initialized || !S_ISREG(inode->i_mode)) + if (!ima_policy_flag || !S_ISREG(inode->i_mode)) return 0; /* Return an IMA_MEASURE, IMA_APPRAISE, IMA_AUDIT action @@ -156,19 +175,33 @@ * Included is the appraise submask. */ action = ima_get_action(inode, mask, function); - if (!action) + violation_check = ((function == FILE_CHECK || function == MMAP_CHECK) && + (ima_policy_flag & IMA_MEASURE)); + if (!action && !violation_check) return 0; must_appraise = action & IMA_APPRAISE; /* Is the appraise rule hook specific? */ - _func = (action & IMA_FILE_APPRAISE) ? FILE_CHECK : function; + if (action & IMA_FILE_APPRAISE) + function = FILE_CHECK; mutex_lock(&inode->i_mutex); - iint = integrity_inode_get(inode); - if (!iint) - goto out; + if (action) { + iint = integrity_inode_get(inode); + if (!iint) + goto out; + } + + if (violation_check) { + ima_rdwr_violation_check(file, iint, action & IMA_MEASURE, + &pathbuf, &pathname); + if (!action) { + rc = 0; + goto out_free; + } + } /* Determine if already appraised/measured based on bitmask * (IMA_MEASURE, IMA_MEASURED, IMA_XXXX_APPRAISE, IMA_XXXX_APPRAISED, @@ -181,28 +214,41 @@ /* Nothing to do, just return existing appraised status */ if (!action) { if (must_appraise) - rc = ima_get_cache_status(iint, _func); + rc = ima_get_cache_status(iint, function); goto out_digsig; } - rc = ima_collect_measurement(iint, file); - if (rc != 0) + template_desc = ima_template_desc_current(); + if ((action & IMA_APPRAISE_SUBMASK) || + strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) != 0) + xattr_ptr = &xattr_value; + + rc = ima_collect_measurement(iint, file, xattr_ptr, &xattr_len); + if (rc != 0) { + if (file->f_flags & O_DIRECT) + rc = (iint->flags & IMA_PERMIT_DIRECTIO) ? 0 : -EACCES; goto out_digsig; + } - pathname = !filename ? ima_d_path(&file->f_path, &pathbuf) : filename; - if (!pathname) - pathname = (const char *)file->f_dentry->d_name.name; + if (!pathname) /* ima_rdwr_violation possibly pre-fetched */ + pathname = ima_d_path(&file->f_path, &pathbuf); if (action & IMA_MEASURE) - ima_store_measurement(iint, file, pathname); + ima_store_measurement(iint, file, pathname, + xattr_value, xattr_len); if (action & IMA_APPRAISE_SUBMASK) - rc = ima_appraise_measurement(_func, iint, file, pathname); + rc = ima_appraise_measurement(function, iint, file, pathname, + xattr_value, xattr_len, opened); if (action & IMA_AUDIT) ima_audit_measurement(iint, pathname); - kfree(pathbuf); + out_digsig: if ((mask & MAY_WRITE) && (iint->flags & IMA_DIGSIG)) rc = -EACCES; + kfree(xattr_value); +out_free: + if (pathbuf) + __putname(pathbuf); out: mutex_unlock(&inode->i_mutex); if ((rc && must_appraise) && (ima_appraise & IMA_APPRAISE_ENFORCE)) @@ -224,7 +270,7 @@ int ima_file_mmap(struct file *file, unsigned long prot) { if (file && (prot & PROT_EXEC)) - return process_measurement(file, NULL, MAY_EXEC, MMAP_CHECK); + return process_measurement(file, MAY_EXEC, MMAP_CHECK, 0); return 0; } @@ -243,10 +289,7 @@ */ int ima_bprm_check(struct linux_binprm *bprm) { - return process_measurement(bprm->file, - (strcmp(bprm->filename, bprm->interp) == 0) ? - bprm->filename : bprm->interp, - MAY_EXEC, BPRM_CHECK); + return process_measurement(bprm->file, MAY_EXEC, BPRM_CHECK, 0); } /** @@ -259,12 +302,11 @@ * On success return 0. On integrity appraisal error, assuming the file * is in policy and IMA-appraisal is in enforcing mode, return -EACCES. */ -int ima_file_check(struct file *file, int mask) +int ima_file_check(struct file *file, int mask, int opened) { - ima_rdwr_violation_check(file); - return process_measurement(file, NULL, - mask & (MAY_READ | MAY_WRITE | MAY_EXEC), - FILE_CHECK); + return process_measurement(file, + mask & (MAY_READ | MAY_WRITE | MAY_EXEC), + FILE_CHECK, opened); } EXPORT_SYMBOL_GPL(ima_file_check); @@ -287,16 +329,30 @@ #endif return 0; /* We rely on module signature checking */ } - return process_measurement(file, NULL, MAY_EXEC, MODULE_CHECK); + return process_measurement(file, MAY_EXEC, MODULE_CHECK, 0); +} + +int ima_fw_from_file(struct file *file, char *buf, size_t size) +{ + if (!file) { + if ((ima_appraise & IMA_APPRAISE_FIRMWARE) && + (ima_appraise & IMA_APPRAISE_ENFORCE)) + return -EACCES; /* INTEGRITY_UNKNOWN */ + return 0; + } + return process_measurement(file, MAY_EXEC, FIRMWARE_CHECK, 0); } static int __init init_ima(void) { int error; + hash_setup(CONFIG_IMA_DEFAULT_HASH); error = ima_init(); - if (!error) + if (!error) { ima_initialized = 1; + ima_update_policy_flag(); + } return error; }