--- zzzz-none-000/linux-3.10.107/security/integrity/ima/ima_appraise.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/security/integrity/ima/ima_appraise.c 2021-02-04 17:41:59.000000000 +0000 @@ -15,6 +15,7 @@ #include #include #include +#include #include "ima.h" @@ -22,6 +23,8 @@ { if (strncmp(str, "off", 3) == 0) ima_appraise = 0; + else if (strncmp(str, "log", 3) == 0) + ima_appraise = IMA_APPRAISE_LOG; else if (strncmp(str, "fix", 3) == 0) ima_appraise = IMA_APPRAISE_FIX; return 1; @@ -43,25 +46,39 @@ } static int ima_fix_xattr(struct dentry *dentry, - struct integrity_iint_cache *iint) + struct integrity_iint_cache *iint) { - iint->ima_xattr.type = IMA_XATTR_DIGEST; - return __vfs_setxattr_noperm(dentry, XATTR_NAME_IMA, - (u8 *)&iint->ima_xattr, - sizeof(iint->ima_xattr), 0); + int rc, offset; + u8 algo = iint->ima_hash->algo; + + if (algo <= HASH_ALGO_SHA1) { + offset = 1; + iint->ima_hash->xattr.sha1.type = IMA_XATTR_DIGEST; + } else { + offset = 0; + iint->ima_hash->xattr.ng.type = IMA_XATTR_DIGEST_NG; + iint->ima_hash->xattr.ng.algo = algo; + } + rc = __vfs_setxattr_noperm(dentry, XATTR_NAME_IMA, + &iint->ima_hash->xattr.data[offset], + (sizeof(iint->ima_hash->xattr) - offset) + + iint->ima_hash->length, 0); + return rc; } /* Return specific func appraised cached result */ enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, int func) { - switch(func) { + switch (func) { case MMAP_CHECK: return iint->ima_mmap_status; case BPRM_CHECK: return iint->ima_bprm_status; case MODULE_CHECK: return iint->ima_module_status; + case FIRMWARE_CHECK: + return iint->ima_firmware_status; case FILE_CHECK: default: return iint->ima_file_status; @@ -71,7 +88,7 @@ static void ima_set_cache_status(struct integrity_iint_cache *iint, int func, enum integrity_status status) { - switch(func) { + switch (func) { case MMAP_CHECK: iint->ima_mmap_status = status; break; @@ -81,6 +98,9 @@ case MODULE_CHECK: iint->ima_module_status = status; break; + case FIRMWARE_CHECK: + iint->ima_firmware_status = status; + break; case FILE_CHECK: default: iint->ima_file_status = status; @@ -90,7 +110,7 @@ static void ima_cache_flags(struct integrity_iint_cache *iint, int func) { - switch(func) { + switch (func) { case MMAP_CHECK: iint->flags |= (IMA_MMAP_APPRAISED | IMA_APPRAISED); break; @@ -100,6 +120,9 @@ case MODULE_CHECK: iint->flags |= (IMA_MODULE_APPRAISED | IMA_APPRAISED); break; + case FIRMWARE_CHECK: + iint->flags |= (IMA_FIRMWARE_APPRAISED | IMA_APPRAISED); + break; case FILE_CHECK: default: iint->flags |= (IMA_FILE_APPRAISED | IMA_APPRAISED); @@ -107,6 +130,50 @@ } } +void ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len, + struct ima_digest_data *hash) +{ + struct signature_v2_hdr *sig; + + if (!xattr_value || xattr_len < 2) + return; + + switch (xattr_value->type) { + case EVM_IMA_XATTR_DIGSIG: + sig = (typeof(sig))xattr_value; + if (sig->version != 2 || xattr_len <= sizeof(*sig)) + return; + hash->algo = sig->hash_algo; + break; + case IMA_XATTR_DIGEST_NG: + hash->algo = xattr_value->digest[0]; + break; + case IMA_XATTR_DIGEST: + /* this is for backward compatibility */ + if (xattr_len == 21) { + unsigned int zero = 0; + if (!memcmp(&xattr_value->digest[16], &zero, 4)) + hash->algo = HASH_ALGO_MD5; + else + hash->algo = HASH_ALGO_SHA1; + } else if (xattr_len == 17) + hash->algo = HASH_ALGO_MD5; + break; + } +} + +int ima_read_xattr(struct dentry *dentry, + struct evm_ima_xattr_data **xattr_value) +{ + struct inode *inode = d_backing_inode(dentry); + + if (!inode->i_op->getxattr) + return 0; + + return vfs_getxattr_alloc(dentry, XATTR_NAME_IMA, (char **)xattr_value, + 0, GFP_NOFS); +} + /* * ima_appraise_measurement - appraise file measurement * @@ -116,30 +183,30 @@ * Return 0 on success, error code otherwise */ int ima_appraise_measurement(int func, struct integrity_iint_cache *iint, - struct file *file, const unsigned char *filename) + struct file *file, const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len, int opened) { - struct dentry *dentry = file->f_dentry; - struct inode *inode = dentry->d_inode; - struct evm_ima_xattr_data *xattr_value = NULL; - enum integrity_status status = INTEGRITY_UNKNOWN; - const char *op = "appraise_data"; + static const char op[] = "appraise_data"; char *cause = "unknown"; - int rc; + struct dentry *dentry = file_dentry(file); + struct inode *inode = d_backing_inode(dentry); + enum integrity_status status = INTEGRITY_UNKNOWN; + int rc = xattr_len, hash_start = 0; - if (!ima_appraise) - return 0; if (!inode->i_op->getxattr) return INTEGRITY_UNKNOWN; - rc = vfs_getxattr_alloc(dentry, XATTR_NAME_IMA, (char **)&xattr_value, - 0, GFP_NOFS); if (rc <= 0) { if (rc && rc != -ENODATA) goto out; cause = "missing-hash"; - status = - (inode->i_size == 0) ? INTEGRITY_PASS : INTEGRITY_NOLABEL; + status = INTEGRITY_NOLABEL; + if (opened & FILE_CREATED) { + iint->flags |= IMA_NEW_FILE; + status = INTEGRITY_PASS; + } goto out; } @@ -153,14 +220,25 @@ goto out; } switch (xattr_value->type) { + case IMA_XATTR_DIGEST_NG: + /* first byte contains algorithm id */ + hash_start = 1; case IMA_XATTR_DIGEST: if (iint->flags & IMA_DIGSIG_REQUIRED) { - cause = "IMA signature required"; + cause = "IMA-signature-required"; status = INTEGRITY_FAIL; break; } - rc = memcmp(xattr_value->digest, iint->ima_xattr.digest, - IMA_DIGEST_SIZE); + if (xattr_len - sizeof(xattr_value->type) - hash_start >= + iint->ima_hash->length) + /* xattr length may be longer. md5 hash in previous + version occupied 20 bytes in xattr, instead of 16 + */ + rc = memcmp(&xattr_value->digest[hash_start], + iint->ima_hash->digest, + iint->ima_hash->length); + else + rc = -EINVAL; if (rc) { cause = "invalid-hash"; status = INTEGRITY_FAIL; @@ -171,9 +249,9 @@ case EVM_IMA_XATTR_DIGSIG: iint->flags |= IMA_DIGSIG; rc = integrity_digsig_verify(INTEGRITY_KEYRING_IMA, - xattr_value->digest, rc - 1, - iint->ima_xattr.digest, - IMA_DIGEST_SIZE); + (const char *)xattr_value, rc, + iint->ima_hash->digest, + iint->ima_hash->length); if (rc == -EOPNOTSUPP) { status = INTEGRITY_UNKNOWN; } else if (rc) { @@ -203,7 +281,6 @@ ima_cache_flags(iint, func); } ima_set_cache_status(iint, func, status); - kfree(xattr_value); return status; } @@ -212,14 +289,14 @@ */ void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file) { - struct dentry *dentry = file->f_dentry; + struct dentry *dentry = file_dentry(file); int rc = 0; /* do not collect and update hash for digital signatures */ if (iint->flags & IMA_DIGSIG) return; - rc = ima_collect_measurement(iint, file); + rc = ima_collect_measurement(iint, file, NULL, NULL); if (rc < 0) return; @@ -237,11 +314,11 @@ */ void ima_inode_post_setattr(struct dentry *dentry) { - struct inode *inode = dentry->d_inode; + struct inode *inode = d_backing_inode(dentry); struct integrity_iint_cache *iint; int must_appraise, rc; - if (!ima_initialized || !ima_appraise || !S_ISREG(inode->i_mode) + if (!(ima_policy_flag & IMA_APPRAISE) || !S_ISREG(inode->i_mode) || !inode->i_op->removexattr) return; @@ -275,11 +352,11 @@ return 0; } -static void ima_reset_appraise_flags(struct inode *inode) +static void ima_reset_appraise_flags(struct inode *inode, int digsig) { struct integrity_iint_cache *iint; - if (!ima_initialized || !ima_appraise || !S_ISREG(inode->i_mode)) + if (!(ima_policy_flag & IMA_APPRAISE) || !S_ISREG(inode->i_mode)) return; iint = integrity_iint_find(inode); @@ -287,18 +364,28 @@ return; iint->flags &= ~IMA_DONE_MASK; + if (digsig) + iint->flags |= IMA_DIGSIG; return; } int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name, const void *xattr_value, size_t xattr_value_len) { + const struct evm_ima_xattr_data *xvalue = xattr_value; int result; result = ima_protect_xattr(dentry, xattr_name, xattr_value, xattr_value_len); if (result == 1) { - ima_reset_appraise_flags(dentry->d_inode); + bool digsig; + + if (!xattr_value_len || (xvalue->type >= IMA_XATTR_LAST)) + return -EINVAL; + digsig = (xvalue->type == EVM_IMA_XATTR_DIGSIG); + if (!digsig && (ima_appraise & IMA_APPRAISE_ENFORCE)) + return -EPERM; + ima_reset_appraise_flags(d_backing_inode(dentry), digsig); result = 0; } return result; @@ -310,7 +397,7 @@ result = ima_protect_xattr(dentry, xattr_name, NULL, 0); if (result == 1) { - ima_reset_appraise_flags(dentry->d_inode); + ima_reset_appraise_flags(d_backing_inode(dentry), 0); result = 0; } return result;