dh/ima-evm-utils-mirror
1
0
Fork 0
mirror of https://git.code.sf.net/p/linux-ima/ima-evm-utils synced 2025-06-30 21:02:33 +02:00
Code Releases Activity

Add support for verifying portable EVM signatures

Browse Source 
Commit 4928548d9d ("Add support for portable EVM format") added
support for generating portable and immutable signatures.  Support
verifying them, using either the security.ima or the user.ima.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
This commit is contained in:
Mimi Zohar
2020-12-07 15:03:01 -05:00
parent 00a0e66a14
commit f4b901d081
1 changed files with 23 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

25
src/evmctl.c
View File

@ -404,6 +404,8 @@ static int calc_evm_hash(const char *file, unsigned char *hash)
}
for (xattrname = evm_config_xattrnames; *xattrname != NULL; xattrname++) {
int use_xattr_ima = 0;
if (!strcmp(*xattrname, XATTR_NAME_SELINUX) && selinux_str) {
err = strlen(selinux_str) + 1;
if (err > sizeof(xattr_value)) {
@ -420,6 +422,15 @@ static int calc_evm_hash(const char *file, unsigned char *hash)
return -1;
}
hex2bin(xattr_value, ima_str, err);
} else if (!strcmp(*xattrname, XATTR_NAME_IMA) && evm_portable){
err = lgetxattr(file, xattr_ima, xattr_value,
sizeof(xattr_value));
if (err < 0) {
log_err("EVM portable sig: %s required\n",
xattr_ima);
return -1;
}
use_xattr_ima = 1;
} else if (!strcmp(*xattrname, XATTR_NAME_CAPS) && (hmac_flags & HMAC_FLAG_CAPS_SET)) {
if (!caps_str)
continue;
@ -442,7 +453,8 @@ static int calc_evm_hash(const char *file, unsigned char *hash)
}
}
/*log_debug("name: %s, value: %s, size: %d\n", *xattrname, xattr_value, err);*/
log_info("name: %s, size: %d\n", *xattrname, err);
log_info("name: %s, size: %d\n",
use_xattr_ima ? xattr_ima : *xattrname, err);
log_debug_dump(xattr_value, err);
err = EVP_DigestUpdate(pctx, xattr_value, err);
if (!err) {
@ -807,11 +819,20 @@ static int verify_evm(const char *file)
return len;
}
if (sig[0] != 0x03) {
if ((sig[0] != EVM_IMA_XATTR_DIGSIG) &&
(sig[0] != EVM_XATTR_PORTABLE_DIGSIG)) {
log_err("%s has no signature\n", xattr_evm);
return -1;
}
if (sig[0] == EVM_XATTR_PORTABLE_DIGSIG) {
if (sig[1] != DIGSIG_VERSION_2) {
log_err("Portable sig: invalid type\n");
return -1;
}
evm_portable = true;
}
sig_hash_algo = imaevm_hash_algo_from_sig(sig + 1);
if (sig_hash_algo < 0) {
log_err("unknown hash algo: %s\n", file);