Merge remote-tracking branch 'upstream-public/pr/828' into development
diff --git a/ChangeLog b/ChangeLog
index f59fed0..bb6222d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -32,6 +32,12 @@
#878, #1019.
* Fix variable used before assignment compilation warnings with IAR
toolchain. Found by gkerrien38.
+ * Fix unchecked return codes from AES, DES and 3DES functions in
+ pem_aes_decrypt(), pem_des_decrypt() and pem_des3_decrypt() respectively.
+ If a call to one of the functions of the cryptographic primitive modules
+ failed, the error may not be noticed by the function
+ mbedtls_pem_read_buffer() causing it to return invalid values. Found by
+ Guido Vranken. #756
= mbed TLS 2.6.0 branch released 2017-08-10
diff --git a/library/pem.c b/library/pem.c
index 8dd86a4..87401ba 100644
--- a/library/pem.c
+++ b/library/pem.c
@@ -134,45 +134,55 @@
/*
* Decrypt with DES-CBC, using PBKDF1 for key derivation
*/
-static void pem_des_decrypt( unsigned char des_iv[8],
- unsigned char *buf, size_t buflen,
- const unsigned char *pwd, size_t pwdlen )
+static int pem_des_decrypt( unsigned char des_iv[8],
+ unsigned char *buf, size_t buflen,
+ const unsigned char *pwd, size_t pwdlen )
{
mbedtls_des_context des_ctx;
unsigned char des_key[8];
+ int ret;
mbedtls_des_init( &des_ctx );
pem_pbkdf1( des_key, 8, des_iv, pwd, pwdlen );
- mbedtls_des_setkey_dec( &des_ctx, des_key );
- mbedtls_des_crypt_cbc( &des_ctx, MBEDTLS_DES_DECRYPT, buflen,
+ if( ( ret = mbedtls_des_setkey_dec( &des_ctx, des_key ) ) != 0 )
+ goto exit;
+ ret = mbedtls_des_crypt_cbc( &des_ctx, MBEDTLS_DES_DECRYPT, buflen,
des_iv, buf, buf );
+exit:
mbedtls_des_free( &des_ctx );
mbedtls_zeroize( des_key, 8 );
+
+ return( ret );
}
/*
* Decrypt with 3DES-CBC, using PBKDF1 for key derivation
*/
-static void pem_des3_decrypt( unsigned char des3_iv[8],
- unsigned char *buf, size_t buflen,
- const unsigned char *pwd, size_t pwdlen )
+static int pem_des3_decrypt( unsigned char des3_iv[8],
+ unsigned char *buf, size_t buflen,
+ const unsigned char *pwd, size_t pwdlen )
{
mbedtls_des3_context des3_ctx;
unsigned char des3_key[24];
+ int ret;
mbedtls_des3_init( &des3_ctx );
pem_pbkdf1( des3_key, 24, des3_iv, pwd, pwdlen );
- mbedtls_des3_set3key_dec( &des3_ctx, des3_key );
- mbedtls_des3_crypt_cbc( &des3_ctx, MBEDTLS_DES_DECRYPT, buflen,
+ if( ( ret = mbedtls_des3_set3key_dec( &des3_ctx, des3_key ) ) != 0 )
+ goto exit;
+ ret = mbedtls_des3_crypt_cbc( &des3_ctx, MBEDTLS_DES_DECRYPT, buflen,
des3_iv, buf, buf );
+exit:
mbedtls_des3_free( &des3_ctx );
mbedtls_zeroize( des3_key, 24 );
+
+ return( ret );
}
#endif /* MBEDTLS_DES_C */
@@ -180,23 +190,28 @@
/*
* Decrypt with AES-XXX-CBC, using PBKDF1 for key derivation
*/
-static void pem_aes_decrypt( unsigned char aes_iv[16], unsigned int keylen,
- unsigned char *buf, size_t buflen,
- const unsigned char *pwd, size_t pwdlen )
+static int pem_aes_decrypt( unsigned char aes_iv[16], unsigned int keylen,
+ unsigned char *buf, size_t buflen,
+ const unsigned char *pwd, size_t pwdlen )
{
mbedtls_aes_context aes_ctx;
unsigned char aes_key[32];
+ int ret;
mbedtls_aes_init( &aes_ctx );
pem_pbkdf1( aes_key, keylen, aes_iv, pwd, pwdlen );
- mbedtls_aes_setkey_dec( &aes_ctx, aes_key, keylen * 8 );
- mbedtls_aes_crypt_cbc( &aes_ctx, MBEDTLS_AES_DECRYPT, buflen,
+ if( ( ret = mbedtls_aes_setkey_dec( &aes_ctx, aes_key, keylen * 8 ) ) != 0 )
+ goto exit;
+ ret = mbedtls_aes_crypt_cbc( &aes_ctx, MBEDTLS_AES_DECRYPT, buflen,
aes_iv, buf, buf );
+exit:
mbedtls_aes_free( &aes_ctx );
mbedtls_zeroize( aes_key, keylen );
+
+ return( ret );
}
#endif /* MBEDTLS_AES_C */
@@ -345,22 +360,30 @@
return( MBEDTLS_ERR_PEM_PASSWORD_REQUIRED );
}
+ ret = 0;
+
#if defined(MBEDTLS_DES_C)
if( enc_alg == MBEDTLS_CIPHER_DES_EDE3_CBC )
- pem_des3_decrypt( pem_iv, buf, len, pwd, pwdlen );
+ ret = pem_des3_decrypt( pem_iv, buf, len, pwd, pwdlen );
else if( enc_alg == MBEDTLS_CIPHER_DES_CBC )
- pem_des_decrypt( pem_iv, buf, len, pwd, pwdlen );
+ ret = pem_des_decrypt( pem_iv, buf, len, pwd, pwdlen );
#endif /* MBEDTLS_DES_C */
#if defined(MBEDTLS_AES_C)
if( enc_alg == MBEDTLS_CIPHER_AES_128_CBC )
- pem_aes_decrypt( pem_iv, 16, buf, len, pwd, pwdlen );
+ ret = pem_aes_decrypt( pem_iv, 16, buf, len, pwd, pwdlen );
else if( enc_alg == MBEDTLS_CIPHER_AES_192_CBC )
- pem_aes_decrypt( pem_iv, 24, buf, len, pwd, pwdlen );
+ ret = pem_aes_decrypt( pem_iv, 24, buf, len, pwd, pwdlen );
else if( enc_alg == MBEDTLS_CIPHER_AES_256_CBC )
- pem_aes_decrypt( pem_iv, 32, buf, len, pwd, pwdlen );
+ ret = pem_aes_decrypt( pem_iv, 32, buf, len, pwd, pwdlen );
#endif /* MBEDTLS_AES_C */
+ if( ret != 0 )
+ {
+ mbedtls_free( buf );
+ return( ret );
+ }
+
/*
* The result will be ASN.1 starting with a SEQUENCE tag, with 1 to 3
* length bytes (allow 4 to be sure) in all known use cases.
diff --git a/tests/suites/test_suite_pem.data b/tests/suites/test_suite_pem.data
index 065e4a2..77546c5 100644
--- a/tests/suites/test_suite_pem.data
+++ b/tests/suites/test_suite_pem.data
@@ -17,11 +17,22 @@
mbedtls_pem_write_buffer:"-----START TEST-----\n":"-----END TEST-----\n":"000102030405060708090A0B0C0D0E0F000102030405060708090A0B0C0D0E0F000102030405060708090A0B0C0D0E0F000102030405060708090A0B0C0D0E0F000102030405060708090A0B0C0D0E0F000102030405060708090A0B0C0D0E0F00":"-----START TEST-----\nAAECAwQFBgcICQoLDA0ODwABAgMEBQYHCAkKCwwNDg8AAQIDBAUGBwgJCgsMDQ4P\nAAECAwQFBgcICQoLDA0ODwABAgMEBQYHCAkKCwwNDg8AAQIDBAUGBwgJCgsMDQ4P\nAA==\n-----END TEST-----\n"
PEM read (DES-EDE3-CBC + invalid iv)
-mbedtls_pem_read_buffer:"^":"$":"^\nProc-Type\: 4,ENCRYPTED\nDEK-Info\: DES-EDE3-CBC,00$":MBEDTLS_ERR_PEM_INVALID_ENC_IV
+mbedtls_pem_read_buffer:"^":"$":"^\nProc-Type\: 4,ENCRYPTED\nDEK-Info\: DES-EDE3-CBC,00$":"pwd":MBEDTLS_ERR_PEM_INVALID_ENC_IV
PEM read (DES-CBC + invalid iv)
-mbedtls_pem_read_buffer:"^":"$":"^\nProc-Type\: 4,ENCRYPTED\nDEK-Info\: DES-CBC,00$":MBEDTLS_ERR_PEM_INVALID_ENC_IV
+mbedtls_pem_read_buffer:"^":"$":"^\nProc-Type\: 4,ENCRYPTED\nDEK-Info\: DES-CBC,00$":"pwd":MBEDTLS_ERR_PEM_INVALID_ENC_IV
PEM read (unknown encryption algorithm)
-mbedtls_pem_read_buffer:"^":"$":"^\nProc-Type\: 4,ENCRYPTED\nDEK-Info\: AES-,00$":MBEDTLS_ERR_PEM_UNKNOWN_ENC_ALG
+mbedtls_pem_read_buffer:"^":"$":"^\nProc-Type\: 4,ENCRYPTED\nDEK-Info\: AES-,00$":"pwd":MBEDTLS_ERR_PEM_UNKNOWN_ENC_ALG
+PEM read (malformed PEM DES-CBC)
+depends_on:MBEDTLS_DES_C:MBEDTLS_CIPHER_MODE_CBC
+mbedtls_pem_read_buffer:"-----BEGIN EC PRIVATE KEY-----":"-----END EC PRIVATE KEY-----":"-----BEGIN EC PRIVATE KEY-----\nProc-Type\: 4,ENCRYPTED\nDEK-Info\: DES-CBC,AA94892A169FA426\n\nMAAA\n-----END EC PRIVATE KEY-----":"pwd":MBEDTLS_ERR_DES_INVALID_INPUT_LENGTH
+
+PEM read (malformed PEM DES-EDE3-CBC)
+depends_on:MBEDTLS_DES_C:MBEDTLS_CIPHER_MODE_CBC
+mbedtls_pem_read_buffer:"-----BEGIN EC PRIVATE KEY-----":"-----END EC PRIVATE KEY-----":"-----BEGIN EC PRIVATE KEY-----\nProc-Type\: 4,ENCRYPTED\nDEK-Info\: DES-EDE3-CBC,AA94892A169FA426\n\nMAAA\n-----END EC PRIVATE KEY-----":"pwd":MBEDTLS_ERR_DES_INVALID_INPUT_LENGTH
+
+PEM read (malformed PEM AES-128-CBC)
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC
+mbedtls_pem_read_buffer:"-----BEGIN EC PRIVATE KEY-----":"-----END EC PRIVATE KEY-----":"-----BEGIN EC PRIVATE KEY-----\nProc-Type\: 4,ENCRYPTED\nDEK-Info\: AES-128-CBC,AA94892A169FA426AA94892A169FA426\n\nMAAA\n-----END EC PRIVATE KEY-----":"pwd":MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH
diff --git a/tests/suites/test_suite_pem.function b/tests/suites/test_suite_pem.function
index 5e02210..c24595d 100644
--- a/tests/suites/test_suite_pem.function
+++ b/tests/suites/test_suite_pem.function
@@ -1,6 +1,8 @@
/* BEGIN_HEADER */
#include "mbedtls/base64.h"
#include "mbedtls/pem.h"
+#include "mbedtls/des.h"
+#include "mbedtls/aes.h"
/* END_HEADER */
/* BEGIN_CASE depends_on:MBEDTLS_PEM_WRITE_C */
@@ -35,16 +37,19 @@
/* END_CASE */
/* BEGIN_CASE depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_AES_C:MBEDTLS_DES_C:MBEDTLS_MD5_C:MBEDTLS_CIPHER_MODE_CBC */
-void mbedtls_pem_read_buffer( char *header, char *footer, char *data, int ret )
+void mbedtls_pem_read_buffer( char *header, char *footer, char *data,
+ char *pwd, int res )
{
mbedtls_pem_context ctx;
+ int ret;
size_t use_len = 0;
+ size_t pwd_len = strlen( pwd );
mbedtls_pem_init( &ctx );
- TEST_ASSERT( mbedtls_pem_read_buffer( &ctx, header, footer,
- (const unsigned char *)data, NULL, 0,
- &use_len ) == ret );
+ ret = mbedtls_pem_read_buffer( &ctx, header, footer, (unsigned char *)data,
+ (unsigned char *)pwd, pwd_len, &use_len );
+ TEST_ASSERT( ret == res );
exit:
mbedtls_pem_free( &ctx );