ima-evm-utils: Add --keyid option
v6 cover ima-evm-utils: Add --keyid option
Allow user to set signature's keyid using `--keyid' option. Keyid should correspond to SKID in certificate. When keyid is calculated using SHA-1 in libimaevm it may mismatch keyid extracted by the kernel from SKID of certificate (the way public key is presented to the kernel), thus making signatures not verifiable. This may happen when certificate is using non SHA-1 SKID (see rfc7093) or just 'unique number' (see rfc5280 4.2.1.2). As a last resort user may specify arbitrary keyid using the new option. Certificate @filename could be used instead of the hex number. And, third option is to read keyid from the cert appended to the key file.
These commits create backward incompatible ABI change for libimaevm,
thus soname should be incremented on release.
Changes from v5:
- ima_read_keyid renamed to imaevm_read_keyid and its return value inverted to match other API functions. Suggested by Stefan Berger
- Rebased over next-testing. Noticed by Mimi Zohar.
Changes from v4:
- ima_read_keyid() API changed. As suggested by Stefan Berger.
Changes from v3:
- ima_read_keyid() is improved to better support both use cases.
Changes from v2:
- Add ima_read_keyid() function to libemaevm and use it in both evmctl (for --keyid) and sign_hash_v2() (for concatenated PEMs). Suggested by Stefan Berger.
- Autodetect PEM by openssl reading it instead of magic string. Suggested by Stefan Berger.
- Trivial change: s/unsigned long int/unsigned long/ for keyid type.
Changes from v1:
- Extract keyid from cert associated to key file.
- Use sizeof instead of constant.
Changes since rfc version:
- `imaevm_params.keyid' now stored as native integer (instead of network order). Suggested by Stefan Berger.
- Added support for `--keyid=@filename'.
Vitaly Chikunov (3):
ima-evm-utils: Allow manual setting keyid for signing
ima-evm-utils: Allow manual setting keyid from a cert file
ima-evm-utils: Read keyid from the cert appended to the key file
README | 5 +++ src/evmctl.c | 27 ++++++++++++++ src/imaevm.h | 2 + src/libimaevm.c | 99 ++++++++++++++++++++++++++++++++++++++++++++++++-- tests/sign_verify.test | 2 + 5 files changed, 132 insertions(+), 3 deletions(-)
Signature · 1 line
2.11.0
PATCH v6 1/3 ima-evm-utils: Allow manual setting keyid for signing
Allow user to set signature's keyid using `--keyid' option. Keyid should correspond to SKID in certificate, when keyid is calculated using SHA-1 in libimaevm it may mismatch keyid extracted by the kernel from SKID of certificate (the way public key is presented to the kernel), thus making signatures not verifiable. This may happen when certificate is using non SHA-1 SKID (see rfc7093) or just 'unique number' (see rfc5280 4.2.1.2). As a last resort user may specify arbitrary keyid using the new option.
This commit creates ABI change for libimaevm, because of adding additional parameter to imaevm_params - newer libimaevm cannot work with older clients.
--- README | 1 + src/evmctl.c | 15 +++++++++++++++ src/imaevm.h | 1 + src/libimaevm.c | 8 +++++--- tests/sign_verify.test | 1 + 5 files changed, 23 insertions(+), 3 deletions(-)
README +1 -0
@@ -48,6 +48,7 @@ OPTIONS --xattr-user store xattrs in user namespace (for testing purposes) --rsa use RSA key type and signing scheme v1 -k, --key path to signing key (default: /etc/keys/{privkey,pubkey}_evm.pem) + --keyid val overwrite signature keyid with a value (for signing) -o, --portable generate portable EVM signatures -p, --pass password for encrypted signing key -r, --recursive recurse into directories (sign)
src/evmctl.c +15 -0
@@ -2514,6 +2514,7 @@ static void usage(void)" --xattr-user store xattrs in user namespace (for testing purposes)\n" " --rsa use RSA key type and signing scheme v1\n" " -k, --key path to signing key (default: /etc/keys/{privkey,pubkey}_evm.pem)\n" +" --keyid val overwrite signature keyid with a value (for signing)\n" " -o, --portable generate portable EVM signatures\n" " -p, --pass password for encrypted signing key\n" " -r, --recursive recurse into directories (sign)\n"
@@ -2594,6 +2595,7 @@ static struct option opts[] = { {"ignore-violations", 0, 0, 141}, {"pcrs", 1, 0, 142}, {"verify-bank", 2, 0, 143}, + {"keyid", 1, 0, 144}, {} };
@@ -2638,6 +2640,8 @@ int main(int argc, char *argv[]) {int err =0 , c, lind;ENGINE *eng =NULL ; +unsigned long keyid; +char *eptr;#if !(OPENSSL_VERSION_NUMBER <0x10100000 ) OPENSSL_init_crypto(
@@ -2785,6 +2789,17 @@ int main(int argc, char *argv[])case 143 : verify_bank = optarg;break ; +case 144 : + errno =0 ; + keyid =strtoul (optarg, &eptr,16 ); +if (errno || eptr - optarg !=strlen (optarg) || + keyid ==ULONG_MAX || keyid >UINT_MAX || + keyid ==0 ) { +log_err ("Invalid keyid value.\n" ); +exit (1 ); + } + imaevm_params.keyid = keyid; +break ;case '?' :exit (1 );break ;
src/imaevm.h +1 -0
@@ -196,6 +196,7 @@ struct libimaevm_params {const char *hash_algo;const char *keyfile;const char *keypass; +uint32_t keyid;/* keyid overriding value, unless 0. */ };struct RSA_ASN1_template {
src/libimaevm.c +5 -3
@@ -45,6 +45,7 @@#include <sys/param.h> #include <sys/stat.h> #include <asm/byteorder.h> +#include <arpa/inet.h> #include <unistd.h> #include <dirent.h> #include <string.h>
@@ -894,7 +895,6 @@ static int sign_hash_v2(const char *algo, const unsigned char *hash,const EVP_MD *md;size_t sigsize;const char *st; -uint32_t keyid;if (!hash) {log_err ("sign_hash_v2: hash is null\n" );
@@ -932,8 +932,10 @@ static int sign_hash_v2(const char *algo, const unsigned char *hash,return -1 ; } -calc_keyid_v2 (&keyid, name, pkey); - hdr->keyid = keyid; +if (imaevm_params.keyid) + hdr->keyid =htonl (imaevm_params.keyid); +else +calc_keyid_v2 (&hdr->keyid, name, pkey); st ="EVP_PKEY_CTX_new" ;if (!(ctx =EVP_PKEY_CTX_new (pkey,NULL )))
tests/sign_verify.test +1 -0
@@ -365,6 +365,7 @@ sign_verify rsa1024 sha256 0x0301 --rsa sign_verify rsa1024 md5 0x030201:K:0080 sign_verify rsa1024 sha1 0x030202:K:0080 sign_verify rsa1024 sha224 0x030207:K:0080 +expect_pass check_sign TYPE=ima KEY=rsa1024 ALG=sha256 PREFIX=0x030204aabbccdd0080 OPTS=--keyid=aabbccdd sign_verify rsa1024 sha256 0x030204:K:0080 try_different_keys try_different_sigs
Signature · 1 line
2.11.0
Mimi Zohar
maintainerRe: [PATCH v6 1/3] ima-evm-utils: Allow manual setting keyid for signing
Quoted 11 lines · Vitaly Chikunov
Allow user to set signature's keyid using `--keyid' option. Keyid should correspond to SKID in certificate, when keyid is calculated using SHA-1 in libimaevm it may mismatch keyid extracted by the kernel from SKID of certificate (the way public key is presented to the kernel), thus making signatures not verifiable. This may happen when certificate is using non SHA-1 SKID (see rfc7093) or just 'unique number' (see rfc5280 4.2.1.2). As a last resort user may specify arbitrary keyid using the new option.
This commit creates ABI change for libimaevm, because of adding additional parameter to
imaevm_params- newer libimaevm cannot work with older clients.
Thank you for highlighting the ABI change.
Quoted 54 lines
Signed-off-by Vitaly Chikunov <[email protected]>Reported-by Elvira Khabirova <[email protected]>Reviewed-by Stefan Berger <[email protected]>--- README | 1 + src/evmctl.c | 15 +++++++++++++++ src/imaevm.h | 1 + src/libimaevm.c | 8 +++++--- tests/sign_verify.test | 1 + 5 files changed, 23 insertions(+), 3 deletions(-)README +1
-0@@ -48,6 +48,7 @@ OPTIONS --xattr-user store xattrs in user namespace (for testing purposes) --rsa use RSA key type and signing scheme v1 -k, --key path to signing key (default: /etc/keys/{privkey,pubkey}_evm.pem) + --keyid val overwrite signature keyid with a value (for signing) -o, --portable generate portable EVM signatures -p, --pass password for encrypted signing key -r, --recursive recurse into directories (sign)src/evmctl.c +4
-0@@ -2514,6 +2514,7 @@ static void usage(void)" --xattr-user store xattrs in user namespace (for testing purposes)\n" " --rsa use RSA key type and signing scheme v1\n" " -k, --key path to signing key (default: /etc/keys/{privkey,pubkey}_evm.pem)\n" +" --keyid val overwrite signature keyid with a value (for signing)\n" " -o, --portable generate portable EVM signatures\n" " -p, --pass password for encrypted signing key\n" " -r, --recursive recurse into directories (sign)\n" @@ -2594,6 +2595,7 @@ static struct option opts[] = { {"ignore-violations", 0, 0, 141}, {"pcrs", 1, 0, 142}, {"verify-bank", 2, 0, 143}, + {"keyid", 1, 0, 144}, {} };@@ -2638,6 +2640,8 @@ int main(int argc, char *argv[]) {int err =0 , c, lind;ENGINE *eng =NULL ; +unsigned long keyid; +char *eptr;#if !(OPENSSL_VERSION_NUMBER <0x10100000 ) OPENSSL_init_crypto(
src/evmctl.c int main(int argc, char *argv[]) · line 2795
Quoted 7 lines
src/evmctl.c +4
-0@@ -2785,6 +2789,17 @@ int main(int argc, char *argv[])case 143 : verify_bank = optarg;break ; +case 144 : + errno =0 ; + keyid =strtoul (optarg, &eptr,16 ); + if (errno || eptr - optarg != strlen(optarg) ||
Before using eptr, shouldn't there be a null test? It's unclear what verifying the resulting string length against the user provided length
provides. Requiring the optarg value to be prefixed with "0x" would
simplify the strlen test. The length would be 2 * sizeof uint + 2. (The subsequent patch wouldn't need a contrived prefix.)
src/evmctl.c int main(int argc, char *argv[]) · line 2796
Quoted 1 line
src/evmctl.c +1
-0+ keyid == ULONG_MAX || keyid > UINT_MAX ||
Why are both of these tests required? When ULONG_MAX and UINT_MAX aren't the same, wouldn't ULONG_MAX always be bigger than UINT_MAX?
Quoted 14 lines
src/evmctl.c +6
-0+ keyid == 0) { +log_err ("Invalid keyid value.\n" ); +exit (1 ); + } + imaevm_params.keyid = keyid; +break ;case '?' :exit (1 );break ;src/imaevm.h +0
-0
src/imaevm.h struct libimaevm_params { · line 199
Quoted 4 lines
src/imaevm.h +1
-0@@ -196,6 +196,7 @@ struct libimaevm_params {const char *hash_algo;const char *keyfile;const char *keypass; +uint32_t keyid;/* keyid overriding value, unless 0. */
If keyid is suppose to be big endiran format, please annotate it in the comment.
Quoted 24 lines
src/imaevm.h +0
-0};struct RSA_ASN1_template {src/libimaevm.c +1
-1@@ -45,6 +45,7 @@#include <sys/param.h> #include <sys/stat.h> #include <asm/byteorder.h> +#include <arpa/inet.h> #include <unistd.h> #include <dirent.h> #include <string.h> @@ -894,7 +895,6 @@ static int sign_hash_v2(const char *algo, const unsigned char *hash,const EVP_MD *md;size_t sigsize;const char *st; -uint32_t keyid;if (!hash) {log_err ("sign_hash_v2: hash is null\n" );
src/libimaevm.c static int sign_hash_v2(const char *algo, const unsigned char *hash, · line 939
Quoted 10 lines
src/libimaevm.c +4
-2@@ -932,8 +932,10 @@ static int sign_hash_v2(const char *algo, const unsigned char *hash,return -1 ; } -calc_keyid_v2 (&keyid, name, pkey); - hdr->keyid = keyid; +if (imaevm_params.keyid) + hdr->keyid =htonl (imaevm_params.keyid); +else +calc_keyid_v2 (&hdr->keyid, name, pkey);
At what point should imaevm_params.keyid be converted to big endian - on usage or setting it?
Mimi
Quoted 14 lines
src/libimaevm.c +0
-0st ="EVP_PKEY_CTX_new" ;if (!(ctx =EVP_PKEY_CTX_new (pkey,NULL )))tests/sign_verify.test +1
-0@@ -365,6 +365,7 @@ sign_verify rsa1024 sha256 0x0301 --rsa sign_verify rsa1024 md5 0x030201:K:0080 sign_verify rsa1024 sha1 0x030202:K:0080 sign_verify rsa1024 sha224 0x030207:K:0080 +expect_pass check_sign TYPE=ima KEY=rsa1024 ALG=sha256 PREFIX=0x030204aabbccdd0080 OPTS=--keyid=aabbccdd sign_verify rsa1024 sha256 0x030204:K:0080 try_different_keys try_different_sigs
Re: [PATCH v6 1/3] ima-evm-utils: Allow manual setting keyid for signing
Mimi,
Quoted 66 lines · Mimi Zohar
Quoted 11 lines · Vitaly Chikunov
Allow user to set signature's keyid using `--keyid' option. Keyid should correspond to SKID in certificate, when keyid is calculated using SHA-1 in libimaevm it may mismatch keyid extracted by the kernel from SKID of certificate (the way public key is presented to the kernel), thus making signatures not verifiable. This may happen when certificate is using non SHA-1 SKID (see rfc7093) or just 'unique number' (see rfc5280 4.2.1.2). As a last resort user may specify arbitrary keyid using the new option.
This commit creates ABI change for libimaevm, because of adding additional parameter to
imaevm_params- newer libimaevm cannot work with older clients.Thank you for highlighting the ABI change.
Quoted 51 lines
Signed-off-by Vitaly Chikunov <[email protected]>Reported-by Elvira Khabirova <[email protected]>Reviewed-by Stefan Berger <[email protected]>--- README | 1 + src/evmctl.c | 15 +++++++++++++++ src/imaevm.h | 1 + src/libimaevm.c | 8 +++++--- tests/sign_verify.test | 1 + 5 files changed, 23 insertions(+), 3 deletions(-)README +1
-0@@ -48,6 +48,7 @@ OPTIONS --xattr-user store xattrs in user namespace (for testing purposes) --rsa use RSA key type and signing scheme v1 -k, --key path to signing key (default: /etc/keys/{privkey,pubkey}_evm.pem) + --keyid val overwrite signature keyid with a value (for signing) -o, --portable generate portable EVM signatures -p, --pass password for encrypted signing key -r, --recursive recurse into directories (sign)src/evmctl.c +4
-0@@ -2514,6 +2514,7 @@ static void usage(void)" --xattr-user store xattrs in user namespace (for testing purposes)\n" " --rsa use RSA key type and signing scheme v1\n" " -k, --key path to signing key (default: /etc/keys/{privkey,pubkey}_evm.pem)\n" +" --keyid val overwrite signature keyid with a value (for signing)\n" " -o, --portable generate portable EVM signatures\n" " -p, --pass password for encrypted signing key\n" " -r, --recursive recurse into directories (sign)\n" @@ -2594,6 +2595,7 @@ static struct option opts[] = { {"ignore-violations", 0, 0, 141}, {"pcrs", 1, 0, 142}, {"verify-bank", 2, 0, 143}, + {"keyid", 1, 0, 144}, {} };@@ -2638,6 +2640,8 @@ int main(int argc, char *argv[]) {int err =0 , c, lind;ENGINE *eng =NULL ; +unsigned long keyid; +char *eptr;
Quoted 12 lines
src/evmctl.c int main(int argc, char *argv[]) · line 2795
Quoted 10 lines
src/evmctl.c +4
-0#if !(OPENSSL_VERSION_NUMBER <0x10100000 ) OPENSSL_init_crypto(@@ -2785,6 +2789,17 @@ int main(int argc, char *argv[])case 143 : verify_bank = optarg;break ; +case 144 : + errno =0 ; + keyid =strtoul (optarg, &eptr,16 ); + if (errno || eptr - optarg != strlen(optarg) ||Before using eptr, shouldn't there be a null test?
AFAIK, strtoul() should never return NULL there. strtoul(3):
If endptr is not NULL, strtoul() stores the address of the first invalid character in *endptr. If there were no digits at all, strtoul() stores the original value of nptr in *endptr (and returns 0). In particular, if *nptr is not '\0' but **endptr is '\0' on return, the entire string is valid.
Quoted 3 lines
It's unclear what
verifying the resulting string length against the user provided length provides.
It shows that whole string is parsed by strtoul, otherwise there is some unparsed garbage, which mean this was not valid number.
Quoted 3 lines
Requiring the optarg value to be prefixed with "0x" would simplify the strlen test. The length would be 2 * sizeof uint + 2. (The subsequent patch wouldn't need a contrived prefix.)
(I do not understand this remark at the moment.)
Base 16 will let user pass keyid just as a string, copy-pasting from somewhere else.
Quoted 5 lines
src/evmctl.c int main(int argc, char *argv[]) · line 2796
Quoted 2 lines
src/evmctl.c +1
-0+ keyid == ULONG_MAX || keyid > UINT_MAX ||Why are both of these tests required? When
ULONG_MAXandUINT_MAXaren't the same, wouldn'tULONG_MAXalways be bigger thanUINT_MAX?
ULONG_MAX is special return value of strtoul. UINT_MAX is a maximum capacity of our keyid variable. So, in the case they are different there is two tests. This also shows that both conditions are checked, without need to solve them in the head.
Quoted 14 lines
Quoted 14 lines
src/evmctl.c +6
-0+ keyid == 0) { +log_err ("Invalid keyid value.\n" ); +exit (1 ); + } + imaevm_params.keyid = keyid; +break ;case '?' :exit (1 );break ;src/imaevm.h +0
-0
Quoted 8 lines
src/imaevm.h struct libimaevm_params { · line 199
Quoted 5 lines
src/imaevm.h +1
-0@@ -196,6 +196,7 @@ struct libimaevm_params {const char *hash_algo;const char *keyfile;const char *keypass; +uint32_t keyid;/* keyid overriding value, unless 0. */ If keyid is suppose to be big endiran format, please annotate it in the comment.
It isn't.
Quoted 28 lines
Quoted 28 lines
src/imaevm.h +0
-0};struct RSA_ASN1_template {src/libimaevm.c +1
-1@@ -45,6 +45,7 @@#include <sys/param.h> #include <sys/stat.h> #include <asm/byteorder.h> +#include <arpa/inet.h> #include <unistd.h> #include <dirent.h> #include <string.h> @@ -894,7 +895,6 @@ static int sign_hash_v2(const char *algo, const unsigned char *hash,const EVP_MD *md;size_t sigsize;const char *st; -uint32_t keyid;if (!hash) {log_err ("sign_hash_v2: hash is null\n" );@@ -932,8 +932,10 @@ static int sign_hash_v2(const char *algo, const unsigned char *hash,return -1 ; }
Quoted 9 lines
src/libimaevm.c static int sign_hash_v2(const char *algo, const unsigned char *hash, · line 939
Quoted 7 lines
src/libimaevm.c +4
-2-calc_keyid_v2 (&keyid, name, pkey); - hdr->keyid = keyid; +if (imaevm_params.keyid) + hdr->keyid =htonl (imaevm_params.keyid); +else +calc_keyid_v2 (&hdr->keyid, name, pkey);At what point should imaevm_params.keyid be converted to big endian - on usage or setting it?
On usage (when storing into header).
Thanks,
Quoted 18 lines
Mimi
Quoted 14 lines
src/libimaevm.c +0
-0st ="EVP_PKEY_CTX_new" ;if (!(ctx =EVP_PKEY_CTX_new (pkey,NULL )))tests/sign_verify.test +1
-0@@ -365,6 +365,7 @@ sign_verify rsa1024 sha256 0x0301 --rsa sign_verify rsa1024 md5 0x030201:K:0080 sign_verify rsa1024 sha1 0x030202:K:0080 sign_verify rsa1024 sha224 0x030207:K:0080 +expect_pass check_sign TYPE=ima KEY=rsa1024 ALG=sha256 PREFIX=0x030204aabbccdd0080 OPTS=--keyid=aabbccdd sign_verify rsa1024 sha256 0x030204:K:0080 try_different_keys try_different_sigs
Mimi Zohar
maintainerRe: [PATCH v6 1/3] ima-evm-utils: Allow manual setting keyid for signing
Hi Vitaly,
Thank you for the detailed explanation.
Quoted 8 lines · Vitaly Chikunov
Quoted 3 lines
Requiring the optarg value to be prefixed with "0x" would simplify the strlen test.
(The subsequent patch wouldn't need a contrived prefix.)(I do not understand this remark at the moment.)
Base 16 will let user pass keyid just as a string, copy-pasting from somewhere else.
strtoul() supports prefixing the ascii-hex string with "0x". To differentiate between a keyid and pathname, why not require the keyid be prefixed with "0x", as opposed to requiring the pathname to be prefixed with '@', like "--keyid @/path/to/cert.pem".
The new test would be "OPTS=--keyid=0xaabbccdd"
thanks,
Mimi
Re: [PATCH v6 1/3] ima-evm-utils: Allow manual setting keyid for signing
Mimi,
Quoted 11 lines · Mimi Zohar
Thank you for the detailed explanation.
Quoted 6 lines · Vitaly Chikunov
Quoted 3 lines
Requiring the optarg value to be prefixed with "0x" would simplify the strlen test.
(The subsequent patch wouldn't need a contrived prefix.)(I do not understand this remark at the moment.)
Quoted 7 lines
Quoted 2 lines
Base 16 will let user pass keyid just as a string, copy-pasting from somewhere else.
strtoul()supports prefixing the ascii-hex string with "0x". To differentiate between a keyid and pathname, why not require the keyid be prefixed with "0x", as opposed to requiring the pathname to be prefixed with '@', like "--keyid @/path/to/cert.pem".
I wanted to avoid (filename vs keyid) ambiguity of the argument to --keyid' - if user have file named "0x00112233" they would have hard time passing it to --keyid'. But, it's impossible to have keyid string starting with "@". So, "@" perfectly distinguish type of `--keyid' argument but "0x" isn't.
Also, in some software (zip, rar) "@" is common prefix meaning value should be taken from the specified file. But, yes, "@" is not common in Unix environments. Do you want me to create separate option like `--keyid-from-file'?
Thanks,
Quoted 6 lines
The new test would be "OPTS=--keyid=0xaabbccdd"
thanks,
Mimi
Mimi Zohar
maintainerRe: [PATCH v6 1/3] ima-evm-utils: Allow manual setting keyid for signing
Hi Vitaly,
Quoted 28 lines · Vitaly Chikunov
Mimi,
Quoted 11 lines · Mimi Zohar
Thank you for the detailed explanation.
Quoted 6 lines · Vitaly Chikunov
Quoted 3 lines
Requiring the optarg value to be prefixed with "0x" would simplify the strlen test.
(The subsequent patch wouldn't need a contrived prefix.)(I do not understand this remark at the moment.)
Quoted 7 lines
Quoted 2 lines
Base 16 will let user pass keyid just as a string, copy-pasting from somewhere else.
strtoul()supports prefixing the ascii-hex string with "0x". To differentiate between a keyid and pathname, why not require the keyid be prefixed with "0x", as opposed to requiring the pathname to be prefixed with '@', like "--keyid @/path/to/cert.pem".I wanted to avoid (filename vs keyid) ambiguity of the argument to
--keyid' - if user have file named "0x00112233" they would have hard time passing it to--keyid'. But, it's impossible to have keyid string starting with "@". So, "@" perfectly distinguish type of `--keyid' argument but "0x" isn't.
Quoted 4 lines
Also, in some software (zip, rar) "@" is common prefix meaning value should be taken from the specified file. But, yes, "@" is not common in Unix environments. Do you want me to create separate option like `--keyid-from-file'?
It's highly unlikely that both the filename and pathname would be prefixed with "0x". Defining a new option might be a good idea. Possibly naming it --extract-cert-keyid, ---cert-keyid, or --keyid- from-cert.
thanks,
Mimi
Re: [PATCH v6 1/3] ima-evm-utils: Allow manual setting keyid for signing
Mimi,
Quoted 32 lines · Mimi Zohar
Quoted 26 lines · Vitaly Chikunov
Quoted 11 lines · Mimi Zohar
Thank you for the detailed explanation.
Quoted 6 lines · Vitaly Chikunov
Quoted 3 lines
Requiring the optarg value to be prefixed with "0x" would simplify the strlen test.
(The subsequent patch wouldn't need a contrived prefix.)(I do not understand this remark at the moment.)
Quoted 7 lines
Quoted 2 lines
Base 16 will let user pass keyid just as a string, copy-pasting from somewhere else.
strtoul()supports prefixing the ascii-hex string with "0x". To differentiate between a keyid and pathname, why not require the keyid be prefixed with "0x", as opposed to requiring the pathname to be prefixed with '@', like "--keyid @/path/to/cert.pem".I wanted to avoid (filename vs keyid) ambiguity of the argument to
--keyid' - if user have file named "0x00112233" they would have hard time passing it to--keyid'. But, it's impossible to have keyid string starting with "@". So, "@" perfectly distinguish type of `--keyid' argument but "0x" isn't.Quoted 4 lines
Also, in some software (zip, rar) "@" is common prefix meaning value should be taken from the specified file. But, yes, "@" is not common in Unix environments. Do you want me to create separate option like `--keyid-from-file'?
Quoted 4 lines
It's highly unlikely that both the filename and pathname would be prefixed with "0x". Defining a new option might be a good idea. Possibly naming it --extract-cert-keyid, ---cert-keyid, or --keyid- from-cert.
It's not unlikely, because people may want to keep cert files named or symlinked by keyid. (For example, local cert database keep cert files symlinked like `f30dd6ad.0'.)
I will add an option, most understandable, perhaps, is `--keyid-from-cert'.
Also, I will remove base 16 from --keyid argument.
Thanks,
Quoted 4 lines
thanks,
Mimi
Mimi Zohar
maintainerRe: [PATCH v6 1/3] ima-evm-utils: Allow manual setting keyid for signing
Hi Vitaly,
Quoted 38 lines · Vitaly Chikunov
Quoted 32 lines · Mimi Zohar
Quoted 26 lines · Vitaly Chikunov
Quoted 11 lines · Mimi Zohar
Thank you for the detailed explanation.
Quoted 6 lines · Vitaly Chikunov
Quoted 3 lines
Requiring the optarg value to be prefixed with "0x" would simplify the strlen test.
(The subsequent patch wouldn't need a contrived prefix.)(I do not understand this remark at the moment.)
Quoted 7 lines
Quoted 2 lines
Base 16 will let user pass keyid just as a string, copy-pasting from somewhere else.
strtoul()supports prefixing the ascii-hex string with "0x". To differentiate between a keyid and pathname, why not require the keyid be prefixed with "0x", as opposed to requiring the pathname to be prefixed with '@', like "--keyid @/path/to/cert.pem".I wanted to avoid (filename vs keyid) ambiguity of the argument to
--keyid' - if user have file named "0x00112233" they would have hard time passing it to--keyid'. But, it's impossible to have keyid string starting with "@". So, "@" perfectly distinguish type of `--keyid' argument but "0x" isn't.Quoted 4 lines
Also, in some software (zip, rar) "@" is common prefix meaning value should be taken from the specified file. But, yes, "@" is not common in Unix environments. Do you want me to create separate option like `--keyid-from-file'?
Quoted 4 lines
It's highly unlikely that both the filename and pathname would be prefixed with "0x". Defining a new option might be a good idea. Possibly naming it --extract-cert-keyid, ---cert-keyid, or --keyid- from-cert.
Quoted 7 lines
It's not unlikely, because people may want to keep cert files named or symlinked by keyid. (For example, local cert database keep cert files symlinked like `f30dd6ad.0'.)
I will add an option, most understandable, perhaps, is `--keyid-from-cert'.
Also, I will remove base 16 from --keyid argument.
I must be missing something. "openssl x509", "keyctl show %keyring:<keyring name>", and "getfattr -m security.ima -e hex --dump" all display the skid in hex. Why would anyone provide the skid as something other than in hex?
thanks,
Mimi
Re: [PATCH v6 1/3] ima-evm-utils: Allow manual setting keyid for signing
Mimi,
Quoted 43 lines · Mimi Zohar
Quoted 42 lines · Vitaly Chikunov
Quoted 32 lines · Mimi Zohar
Quoted 26 lines · Vitaly Chikunov
Quoted 11 lines · Mimi Zohar
Thank you for the detailed explanation.
Quoted 6 lines · Vitaly Chikunov
Quoted 3 lines
Requiring the optarg value to be prefixed with "0x" would simplify the strlen test.
(The subsequent patch wouldn't need a contrived prefix.)(I do not understand this remark at the moment.)
Quoted 7 lines
Quoted 2 lines
Base 16 will let user pass keyid just as a string, copy-pasting from somewhere else.
strtoul()supports prefixing the ascii-hex string with "0x". To differentiate between a keyid and pathname, why not require the keyid be prefixed with "0x", as opposed to requiring the pathname to be prefixed with '@', like "--keyid @/path/to/cert.pem".I wanted to avoid (filename vs keyid) ambiguity of the argument to
--keyid' - if user have file named "0x00112233" they would have hard time passing it to--keyid'. But, it's impossible to have keyid string starting with "@". So, "@" perfectly distinguish type of `--keyid' argument but "0x" isn't.Quoted 4 lines
Also, in some software (zip, rar) "@" is common prefix meaning value should be taken from the specified file. But, yes, "@" is not common in Unix environments. Do you want me to create separate option like `--keyid-from-file'?
Quoted 4 lines
It's highly unlikely that both the filename and pathname would be prefixed with "0x". Defining a new option might be a good idea. Possibly naming it --extract-cert-keyid, ---cert-keyid, or --keyid- from-cert.
It's not unlikely, because people may want to keep cert files named or symlinked by keyid. (For example, local cert database keep cert files symlinked like `f30dd6ad.0'.)
Quoted 8 lines
Quoted 3 lines
I will add an option, most understandable, perhaps, is `--keyid-from-cert'.
Also, I will remove base 16 from --keyid argument.
I must be missing something. "openssl x509", "keyctl show %keyring:<keyring name>", and "getfattr -m security.ima -e hex --dump" all display the skid in hex. Why would anyone provide the skid as something other than in hex?
Ah, I thought you want '0x' prefix mandatory. Will not remove base 16 then. Also, /proc/keys shows keyid without '0x' prefix.
Thanks,
Quoted 5 lines
thanks,
Mimi
Mimi Zohar
maintainerRe: [PATCH v6 1/3] ima-evm-utils: Allow manual setting keyid for signing
Quoted 50 lines · Vitaly Chikunov
Mimi,
Quoted 47 lines · Mimi Zohar
Quoted 45 lines · Vitaly Chikunov
Quoted 32 lines · Mimi Zohar
Quoted 26 lines · Vitaly Chikunov
Quoted 11 lines · Mimi Zohar
Thank you for the detailed explanation.
Quoted 6 lines · Vitaly Chikunov
Quoted 3 lines
Requiring the optarg value to be prefixed with "0x" would simplify the strlen test.
(The subsequent patch wouldn't need a contrived prefix.)(I do not understand this remark at the moment.)
Quoted 7 lines
Quoted 2 lines
Base 16 will let user pass keyid just as a string, copy-pasting from somewhere else.
strtoul()supports prefixing the ascii-hex string with "0x". To differentiate between a keyid and pathname, why not require the keyid be prefixed with "0x", as opposed to requiring the pathname to be prefixed with '@', like "--keyid @/path/to/cert.pem".I wanted to avoid (filename vs keyid) ambiguity of the argument to
--keyid' - if user have file named "0x00112233" they would have hard time passing it to--keyid'. But, it's impossible to have keyid string starting with "@". So, "@" perfectly distinguish type of `--keyid' argument but "0x" isn't.Quoted 4 lines
Also, in some software (zip, rar) "@" is common prefix meaning value should be taken from the specified file. But, yes, "@" is not common in Unix environments. Do you want me to create separate option like `--keyid-from-file'?
Quoted 4 lines
It's highly unlikely that both the filename and pathname would be prefixed with "0x". Defining a new option might be a good idea. Possibly naming it --extract-cert-keyid, ---cert-keyid, or --keyid- from-cert.
It's not unlikely, because people may want to keep cert files named or symlinked by keyid. (For example, local cert database keep cert files symlinked like `f30dd6ad.0'.)
I will add an option, most understandable, perhaps, is `--keyid-from-cert'.
Also, I will remove base 16 from --keyid argument.
Quoted 7 lines
Quoted 4 lines
I must be missing something. "openssl x509", "keyctl show %keyring:<keyring name>", and "getfattr -m security.ima -e hex --dump" all display the skid in hex. Why would anyone provide the skid as something other than in hex?
Ah, I thought you want '0x' prefix mandatory. Will not remove base 16 then. Also,
/proc/keysshows keyid without '0x' prefix.
Why? One doesn't preclude the other. "keyid = strtoul(optarg, &eptr,
16);" recognizes an "0x" prefixed string as being ascii-hex.
Mimi
PATCH v6 2/3 ima-evm-utils: Allow manual setting keyid from a cert file
In reply to Vitaly ChikunovAllow user to specify `--keyid @/path/to/cert.pem' to extract keyid from SKID of the certificate file. PEM or DER format is auto-detected.
--keyid' option is reused instead of adding a new option (like possible --cert') to signify to the user it's only keyid extraction and nothing more.
This commit creates ABI change for libimaevm, due to adding new function ima_read_keyid(). Newer clients cannot work with older libimaevm. Together with previous commit it creates backward-incompatible ABI change, thus soname should be incremented on release.
--- README | 1 + src/evmctl.c | 22 ++++++++++--- src/imaevm.h | 1 + src/libimaevm.c | 89 ++++++++++++++++++++++++++++++++++++++++++++++++++ tests/sign_verify.test | 1 + 5 files changed, 109 insertions(+), 5 deletions(-)
README +1 -0
@@ -49,6 +49,7 @@ OPTIONS --rsa use RSA key type and signing scheme v1 -k, --key path to signing key (default: /etc/keys/{privkey,pubkey}_evm.pem) --keyid val overwrite signature keyid with a value (for signing) + val is a x509 cert file if prefixed with '@' -o, --portable generate portable EVM signatures -p, --pass password for encrypted signing key -r, --recursive recurse into directories (sign)
src/evmctl.c +17 -5
@@ -42,6 +42,7 @@#include <sys/param.h> #include <sys/stat.h> #include <sys/ioctl.h> +#include <arpa/inet.h> #include <fcntl.h> #include <unistd.h> #include <stdlib.h>
@@ -57,12 +58,14 @@#include <termios.h> #include <assert.h> +#include <openssl/asn1.h> #include <openssl/sha.h> #include <openssl/pem.h> #include <openssl/hmac.h> #include <openssl/err.h> #include <openssl/rsa.h> #include <openssl/engine.h> +#include <openssl/x509v3.h> #include "hash_info.h" #include "pcr.h" #include "utils.h"
@@ -2515,6 +2518,7 @@ static void usage(void)" --rsa use RSA key type and signing scheme v1\n" " -k, --key path to signing key (default: /etc/keys/{privkey,pubkey}_evm.pem)\n" " --keyid val overwrite signature keyid with a value (for signing)\n" +" val is a x509 cert file if prefixed with '@'\n" " -o, --portable generate portable EVM signatures\n" " -p, --pass password for encrypted signing key\n" " -r, --recursive recurse into directories (sign)\n"
@@ -2641,7 +2645,6 @@ int main(int argc, char *argv[])int err =0 , c, lind;ENGINE *eng =NULL ;unsigned long keyid; -char *eptr;#if !(OPENSSL_VERSION_NUMBER <0x10100000 ) OPENSSL_init_crypto(
@@ -2790,10 +2793,19 @@ int main(int argc, char *argv[]) verify_bank = optarg;break ;case 144 : - errno =0 ; - keyid =strtoul (optarg, &eptr,16 ); -if (errno || eptr - optarg !=strlen (optarg) || - keyid ==ULONG_MAX || keyid >UINT_MAX || +if (optarg[0 ] =='@' ) { + keyid =imaevm_read_keyid (optarg +1 ); + }else { +char *eptr; + + errno =0 ; + keyid =strtoul (optarg, &eptr,16 ); +if (eptr - optarg !=strlen (optarg) || errno) { +log_err ("Invalid keyid value.\n" ); +exit (1 ); + } + } +if (keyid ==ULONG_MAX || keyid >UINT_MAX || keyid ==0 ) {log_err ("Invalid keyid value.\n" );exit (1 );
src/imaevm.h +1 -0
@@ -219,6 +219,7 @@ EVP_PKEY *read_pub_pkey(const char *keyfile, int x509);void calc_keyid_v1 (uint8_t *keyid,char *str,const unsigned char *pkey,int len);void calc_keyid_v2 (uint32_t *keyid,char *str,EVP_PKEY *pkey);int key2bin (RSA *key,unsigned char *pub); +uint32_t imaevm_read_keyid (const char *certfile);int sign_hash (const char *algo,const unsigned char *hash,int size,const char *keyfile,const char *keypass,unsigned char *sig);int verify_hash (const char *file,const unsigned char *hash,int size,unsigned char *sig,int siglen);
src/libimaevm.c +89 -0
101 lines not on this page · raw message
tests/sign_verify.test +1 -0
@@ -366,6 +366,7 @@ sign_verify rsa1024 md5 0x030201:K:0080 sign_verify rsa1024 sha1 0x030202:K:0080 sign_verify rsa1024 sha224 0x030207:K:0080 expect_pass check_sign TYPE=ima KEY=rsa1024 ALG=sha256 PREFIX=0x030204aabbccdd0080 OPTS=--keyid=aabbccdd +expect_pass check_sign TYPE=ima KEY=rsa1024 ALG=sha256 PREFIX=0x030204:K:0080 [email protected] sign_verify rsa1024 sha256 0x030204:K:0080 try_different_keys try_different_sigs
Signature · 1 line
2.11.0
Mimi Zohar
maintainerRe: [PATCH v6 2/3] ima-evm-utils: Allow manual setting keyid from a cert file
Quoted 7 lines · Vitaly Chikunov
src/libimaevm.c +6
-0+/** +* imaevm_read_keyid() - Read 32-bit keyid from the cert file. +* @certfile: File possibly containing certificate in DER/PEM format. +* +* Try to read keyid from Subject Key Identifier (SKID) of certificate. +* Autodetect if cert is in PEM or DER encoding.
src/libimaevm.c void calc_keyid_v2(uint32_t *keyid, char *str, EVP_PKEY *pkey) · line 837
Quoted 10 lines
src/libimaevm.c +10
-0+* +* Return: 0 on error; +* 32-bit keyid as unsigned integer in host order. +*/ +uint32_t imaevm_read_keyid (const char *certfile) +{ +uint32_t keyid_raw =0 ; + +__read_keyid (&keyid_raw, certfile,KEYID_FILE_UNK_CERT ); +return ntohl (keyid_raw);
On error, __read_keyid() returns < 0, but the return value isn't checked before calling ntohl. In either case, is imaevm_params.keyid suppose to be big endian byte order? If so, the call to htonl in sign_hash_v2() would be unnecessary.
thanks,
Mimi
Re: [PATCH v6 2/3] ima-evm-utils: Allow manual setting keyid from a cert file
Quoted 13 lines · Mimi Zohar
Quoted 12 lines · Vitaly Chikunov
src/libimaevm.c +11
-0+/** +* imaevm_read_keyid() - Read 32-bit keyid from the cert file. +* @certfile: File possibly containing certificate in DER/PEM format. +* +* Try to read keyid from Subject Key Identifier (SKID) of certificate. +* Autodetect if cert is in PEM or DER encoding. +* +* Return: 0 on error; +* 32-bit keyid as unsigned integer in host order. +*/ +uint32_t imaevm_read_keyid (const char *certfile)
Quoted 8 lines
src/libimaevm.c void calc_keyid_v2(uint32_t *keyid, char *str, EVP_PKEY *pkey) · line 837
Quoted 5 lines
src/libimaevm.c +5
-0+{ +uint32_t keyid_raw =0 ; + +__read_keyid (&keyid_raw, certfile,KEYID_FILE_UNK_CERT ); +return ntohl (keyid_raw);On error,
__read_keyid()returns < 0, but the return value isn't checked before calling ntohl.
It does not need to be checked, because it also does not change value pointed by &keyid_raw' (which is 0 by default). Yes, this is not mentioned in the __read_keyid' description. But, otherwise (to change pointed value on error) would be a bug.
Quoted 2 lines
In either case, is imaevm_params.keyid
suppose to be big endian byte order?
No, it's in native order. This looked reasonable, since it could be presented to the user as a hex number.
Thanks,
Quoted 6 lines
If so, the call to htonl in
sign_hash_v2()would be unnecessary.thanks,
Mimi
Mimi Zohar
maintainerRe: [PATCH v6 2/3] ima-evm-utils: Allow manual setting keyid from a cert file
Hi Vitaly,
Quoted 5 lines · Vitaly Chikunov
Quoted 2 lines
In either case, is imaevm_params.keyid
suppose to be big endian byte order?No, it's in native order. This looked reasonable, since it could be presented to the user as a hex number.
My confusion must have come from the __read_keyid() comment.
+ * @keyid: Pointer to 32-bit value in network order, can be
unaligned.
Please annotate the comment and the imaevm_params.keyid appropriately.
thanks,
Mimi
PATCH v6 3/3 ima-evm-utils: Read keyid from the cert appended to the key file
In reply to Vitaly ChikunovAllow to have certificate appended to the private key of `--key' specified (PEM) file (for v2 signing) to facilitate reading of keyid from the associated cert. This will allow users to have private and public key as a single file. There is no check that public key form the cert matches associated private key.
--- README | 3 +++ src/libimaevm.c | 8 +++++--- 2 files changed, 8 insertions(+), 3 deletions(-)
README +3 -0
@@ -127,6 +127,9 @@ for signing and importing the key. Second key format uses X509 DER encoded public key certificates and uses asymmetric key support in the kernel (since kernel 3.9). CONFIG_INTEGRITY_ASYMMETRIC_KEYS must be enabled (default). +For v2 signatures x509 certificate with the public key could be appended to the private +key (both are in PEM format) to properly determine its Subject Key Identifier (SKID). + Integrity keyrings ----------------
src/libimaevm.c +5 -3
@@ -1021,10 +1021,12 @@ static int sign_hash_v2(const char *algo, const unsigned char *hash,return -1 ; } -if (imaevm_params.keyid) +if (imaevm_params.keyid) { hdr->keyid =htonl (imaevm_params.keyid); -else -calc_keyid_v2 (&hdr->keyid, name, pkey); + }else { +if (__read_keyid (&hdr->keyid, keyfile,KEYID_FILE_PEM_KEY )) +calc_keyid_v2 (&hdr->keyid, name, pkey); + } st ="EVP_PKEY_CTX_new" ;if (!(ctx =EVP_PKEY_CTX_new (pkey,NULL )))
Signature · 1 line
2.11.0
Mimi Zohar
maintainerRe: [PATCH v6 3/3] ima-evm-utils: Read keyid from the cert appended to the key file
Quoted 5 lines · Vitaly Chikunov
Allow to have certificate appended to the private key of `--key' specified (PEM) file (for v2 signing) to facilitate reading of keyid from the associated cert. This will allow users to have private and public key as a single file. There is no check that public key form the cert matches associated private key.
Is this a standard formats for storing the public and private key in the same file?
Mimi
Re: [PATCH v6 3/3] ima-evm-utils: Read keyid from the cert appended to the key file
Mimi,
Quoted 9 lines · Mimi Zohar
Quoted 5 lines · Vitaly Chikunov
Allow to have certificate appended to the private key of `--key' specified (PEM) file (for v2 signing) to facilitate reading of keyid from the associated cert. This will allow users to have private and public key as a single file. There is no check that public key form the cert matches associated private key.
Is this a standard formats for storing the public and private key in the same file?
I am not aware of any standard to keep ASCII armored text x509 cert together with the private key in the same file. But, it's common usage for some web servers, such as NGINX. People commonly suggest doing it in that context:
https://stackoverflow.com/questions/991758/how-to-get-pem-file-from-key-and-crt-files
"cat server.crt server.key > server.includesprivatekey.pem" "cat server.crt server.key > server.pem"
Thanks,
Quoted 2 lines
Mimi
Mimi Zohar
maintainerRe: [PATCH v6 3/3] ima-evm-utils: Read keyid from the cert appended to the key file
In reply to Vitaly ChikunovHi Vitaly,
Quoted 8 lines · Vitaly Chikunov
src/libimaevm.c +0
-0@@ -1021,10 +1021,12 @@ static int sign_hash_v2(const char *algo, const unsigned char *hash,return -1 ; }
src/libimaevm.c static int sign_hash_v2(const char *algo, const unsigned char *hash, · line 1029
Quoted 10 lines
src/libimaevm.c +5
-3-if (imaevm_params.keyid) +if (imaevm_params.keyid) { hdr->keyid =htonl (imaevm_params.keyid); -else -calc_keyid_v2 (&hdr->keyid, name, pkey); + }else { +if (__read_keyid (&hdr->keyid, keyfile,KEYID_FILE_PEM_KEY )) +calc_keyid_v2 (&hdr->keyid, name, pkey); + }
If the call to __read_keyid() was independent of the test and call to calc_keyid_v2(), it would make reading code the easier to understand.
result = __read_keyid(...);
if (result < 0)
calc_keyid_v2(...);
thanks,
Mimi
Quoted 3 lines
src/libimaevm.c +0
-0st ="EVP_PKEY_CTX_new" ;if (!(ctx =EVP_PKEY_CTX_new (pkey,NULL )))
Re: [PATCH v6 3/3] ima-evm-utils: Read keyid from the cert appended to the key file
Mimi,
Quoted 23 lines · Mimi Zohar
Quoted 8 lines · Vitaly Chikunov
src/libimaevm.c +0
-0@@ -1021,10 +1021,12 @@ static int sign_hash_v2(const char *algo, const unsigned char *hash,return -1 ; }src/libimaevm.c static int sign_hash_v2(const char *algo, const unsigned char *hash, · line 1029
Quoted 10 lines
src/libimaevm.c +5
-3-if (imaevm_params.keyid) +if (imaevm_params.keyid) { hdr->keyid =htonl (imaevm_params.keyid); -else -calc_keyid_v2 (&hdr->keyid, name, pkey); + }else { +if (__read_keyid (&hdr->keyid, keyfile,KEYID_FILE_PEM_KEY )) +calc_keyid_v2 (&hdr->keyid, name, pkey); + }If the call to
__read_keyid()was independent of the test and call tocalc_keyid_v2(), it would make reading code the easier to understand.
Quoted 3 lines
result =
__read_keyid(...);
if (result < 0)calc_keyid_v2(...);
No problem to add additional variable and check __read_keyid indirectly. But, how is this independent? Call to calc_keyid_v2 is dependent to __read_keyid result.
Thanks,
Quoted 9 lines
thanks,
Mimi
Quoted 3 lines
src/libimaevm.c +0
-0st ="EVP_PKEY_CTX_new" ;if (!(ctx =EVP_PKEY_CTX_new (pkey,NULL )))
Re: [PATCH v6 3/3] ima-evm-utils: Read keyid from the cert appended to the key file
Mimi,
Quoted 24 lines · Vitaly Chikunov
Quoted 23 lines · Mimi Zohar
Quoted 8 lines · Vitaly Chikunov
src/libimaevm.c +0
-0@@ -1021,10 +1021,12 @@ static int sign_hash_v2(const char *algo, const unsigned char *hash,return -1 ; }src/libimaevm.c static int sign_hash_v2(const char *algo, const unsigned char *hash, · line 1029
Quoted 10 lines
src/libimaevm.c +5
-3-if (imaevm_params.keyid) +if (imaevm_params.keyid) { hdr->keyid =htonl (imaevm_params.keyid); -else -calc_keyid_v2 (&hdr->keyid, name, pkey); + }else { +if (__read_keyid (&hdr->keyid, keyfile,KEYID_FILE_PEM_KEY )) +calc_keyid_v2 (&hdr->keyid, name, pkey); + }If the call to
__read_keyid()was independent of the test and call tocalc_keyid_v2(), it would make reading code the easier to understand.
Quoted 7 lines
Quoted 3 lines
result =
__read_keyid(...);
if (result < 0)calc_keyid_v2(...);No problem to add additional variable and check
__read_keyidindirectly. But, how is this independent? Call tocalc_keyid_v2is dependent to__read_keyidresult.
I think I understood what you meant.
Thanks,
Quoted 12 lines
Thanks,
Quoted 9 lines
thanks,
Mimi
Quoted 3 lines
src/libimaevm.c +0
-0st ="EVP_PKEY_CTX_new" ;if (!(ctx =EVP_PKEY_CTX_new (pkey,NULL )))