| /* |
| * Public Key layer for parsing key files and structures |
| * |
| * Copyright (C) 2006-2014, ARM Limited, All Rights Reserved |
| * |
| * This file is part of mbed TLS (https://polarssl.org) |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with this program; if not, write to the Free Software Foundation, Inc., |
| * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| */ |
| |
| #if !defined(POLARSSL_CONFIG_FILE) |
| #include "polarssl/config.h" |
| #else |
| #include POLARSSL_CONFIG_FILE |
| #endif |
| |
| #if defined(POLARSSL_PK_PARSE_C) |
| |
| #include "polarssl/pk.h" |
| #include "polarssl/asn1.h" |
| #include "polarssl/oid.h" |
| |
| #include <string.h> |
| |
| #if defined(POLARSSL_RSA_C) |
| #include "polarssl/rsa.h" |
| #endif |
| #if defined(POLARSSL_ECP_C) |
| #include "polarssl/ecp.h" |
| #endif |
| #if defined(POLARSSL_ECDSA_C) |
| #include "polarssl/ecdsa.h" |
| #endif |
| #if defined(POLARSSL_PEM_PARSE_C) |
| #include "polarssl/pem.h" |
| #endif |
| #if defined(POLARSSL_PKCS5_C) |
| #include "polarssl/pkcs5.h" |
| #endif |
| #if defined(POLARSSL_PKCS12_C) |
| #include "polarssl/pkcs12.h" |
| #endif |
| |
| #if defined(POLARSSL_PLATFORM_C) |
| #include "polarssl/platform.h" |
| #else |
| #include <stdlib.h> |
| #define polarssl_malloc malloc |
| #define polarssl_free free |
| #endif |
| |
| #if defined(POLARSSL_FS_IO) |
| /* Implementation that should never be optimized out by the compiler */ |
| static void polarssl_zeroize( void *v, size_t n ) { |
| volatile unsigned char *p = v; while( n-- ) *p++ = 0; |
| } |
| |
| /* |
| * Load all data from a file into a given buffer. |
| */ |
| int pk_load_file( const char *path, unsigned char **buf, size_t *n ) |
| { |
| FILE *f; |
| long size; |
| |
| if( ( f = fopen( path, "rb" ) ) == NULL ) |
| return( POLARSSL_ERR_PK_FILE_IO_ERROR ); |
| |
| fseek( f, 0, SEEK_END ); |
| if( ( size = ftell( f ) ) == -1 ) |
| { |
| fclose( f ); |
| return( POLARSSL_ERR_PK_FILE_IO_ERROR ); |
| } |
| fseek( f, 0, SEEK_SET ); |
| |
| *n = (size_t) size; |
| |
| if( *n + 1 == 0 || |
| ( *buf = (unsigned char *) polarssl_malloc( *n + 1 ) ) == NULL ) |
| { |
| fclose( f ); |
| return( POLARSSL_ERR_PK_MALLOC_FAILED ); |
| } |
| |
| if( fread( *buf, 1, *n, f ) != *n ) |
| { |
| fclose( f ); |
| polarssl_free( *buf ); |
| return( POLARSSL_ERR_PK_FILE_IO_ERROR ); |
| } |
| |
| fclose( f ); |
| |
| (*buf)[*n] = '\0'; |
| |
| return( 0 ); |
| } |
| |
| /* |
| * Load and parse a private key |
| */ |
| int pk_parse_keyfile( pk_context *ctx, |
| const char *path, const char *pwd ) |
| { |
| int ret; |
| size_t n; |
| unsigned char *buf; |
| |
| if( ( ret = pk_load_file( path, &buf, &n ) ) != 0 ) |
| return( ret ); |
| |
| if( pwd == NULL ) |
| ret = pk_parse_key( ctx, buf, n, NULL, 0 ); |
| else |
| ret = pk_parse_key( ctx, buf, n, |
| (const unsigned char *) pwd, strlen( pwd ) ); |
| |
| polarssl_zeroize( buf, n + 1 ); |
| polarssl_free( buf ); |
| |
| return( ret ); |
| } |
| |
| /* |
| * Load and parse a public key |
| */ |
| int pk_parse_public_keyfile( pk_context *ctx, const char *path ) |
| { |
| int ret; |
| size_t n; |
| unsigned char *buf; |
| |
| if( ( ret = pk_load_file( path, &buf, &n ) ) != 0 ) |
| return( ret ); |
| |
| ret = pk_parse_public_key( ctx, buf, n ); |
| |
| polarssl_zeroize( buf, n + 1 ); |
| polarssl_free( buf ); |
| |
| return( ret ); |
| } |
| #endif /* POLARSSL_FS_IO */ |
| |
| #if defined(POLARSSL_ECP_C) |
| /* Minimally parse an ECParameters buffer to and asn1_buf |
| * |
| * ECParameters ::= CHOICE { |
| * namedCurve OBJECT IDENTIFIER |
| * specifiedCurve SpecifiedECDomain -- = SEQUENCE { ... } |
| * -- implicitCurve NULL |
| * } |
| */ |
| static int pk_get_ecparams( unsigned char **p, const unsigned char *end, |
| asn1_buf *params ) |
| { |
| int ret; |
| |
| /* Tag may be either OID or SEQUENCE */ |
| params->tag = **p; |
| if( params->tag != ASN1_OID |
| #if defined(POLARSSL_PK_PARSE_EC_EXTENDED) |
| && params->tag != ( ASN1_CONSTRUCTED | ASN1_SEQUENCE ) |
| #endif |
| ) |
| { |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + |
| POLARSSL_ERR_ASN1_UNEXPECTED_TAG ); |
| } |
| |
| if( ( ret = asn1_get_tag( p, end, ¶ms->len, params->tag ) ) != 0 ) |
| { |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| } |
| |
| params->p = *p; |
| *p += params->len; |
| |
| if( *p != end ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + |
| POLARSSL_ERR_ASN1_LENGTH_MISMATCH ); |
| |
| return( 0 ); |
| } |
| |
| #if defined(POLARSSL_PK_PARSE_EC_EXTENDED) |
| /* |
| * Parse a SpecifiedECDomain (SEC 1 C.2) and (mostly) fill the group with it. |
| * WARNING: the resulting group should only be used with |
| * pk_group_id_from_specified(), since its base point may not be set correctly |
| * if it was encoded compressed. |
| * |
| * SpecifiedECDomain ::= SEQUENCE { |
| * version SpecifiedECDomainVersion(ecdpVer1 | ecdpVer2 | ecdpVer3, ...), |
| * fieldID FieldID {{FieldTypes}}, |
| * curve Curve, |
| * base ECPoint, |
| * order INTEGER, |
| * cofactor INTEGER OPTIONAL, |
| * hash HashAlgorithm OPTIONAL, |
| * ... |
| * } |
| * |
| * We only support prime-field as field type, and ignore hash and cofactor. |
| */ |
| static int pk_group_from_specified( const asn1_buf *params, ecp_group *grp ) |
| { |
| int ret; |
| unsigned char *p = params->p; |
| const unsigned char * const end = params->p + params->len; |
| const unsigned char *end_field, *end_curve; |
| size_t len; |
| int ver; |
| |
| /* SpecifiedECDomainVersion ::= INTEGER { 1, 2, 3 } */ |
| if( ( ret = asn1_get_int( &p, end, &ver ) ) != 0 ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| |
| if( ver < 1 || ver > 3 ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT ); |
| |
| /* |
| * FieldID { FIELD-ID:IOSet } ::= SEQUENCE { -- Finite field |
| * fieldType FIELD-ID.&id({IOSet}), |
| * parameters FIELD-ID.&Type({IOSet}{@fieldType}) |
| * } |
| */ |
| if( ( ret = asn1_get_tag( &p, end, &len, |
| ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 ) |
| return( ret ); |
| |
| end_field = p + len; |
| |
| /* |
| * FIELD-ID ::= TYPE-IDENTIFIER |
| * FieldTypes FIELD-ID ::= { |
| * { Prime-p IDENTIFIED BY prime-field } | |
| * { Characteristic-two IDENTIFIED BY characteristic-two-field } |
| * } |
| * prime-field OBJECT IDENTIFIER ::= { id-fieldType 1 } |
| */ |
| if( ( ret = asn1_get_tag( &p, end_field, &len, ASN1_OID ) ) != 0 ) |
| return( ret ); |
| |
| if( len != OID_SIZE( OID_ANSI_X9_62_PRIME_FIELD ) || |
| memcmp( p, OID_ANSI_X9_62_PRIME_FIELD, len ) != 0 ) |
| { |
| return( POLARSSL_ERR_PK_FEATURE_UNAVAILABLE ); |
| } |
| |
| p += len; |
| |
| /* Prime-p ::= INTEGER -- Field of size p. */ |
| if( ( ret = asn1_get_mpi( &p, end_field, &grp->P ) ) != 0 ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| |
| grp->pbits = mpi_msb( &grp->P ); |
| |
| if( p != end_field ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + |
| POLARSSL_ERR_ASN1_LENGTH_MISMATCH ); |
| |
| /* |
| * Curve ::= SEQUENCE { |
| * a FieldElement, |
| * b FieldElement, |
| * seed BIT STRING OPTIONAL |
| * -- Shall be present if used in SpecifiedECDomain |
| * -- with version equal to ecdpVer2 or ecdpVer3 |
| * } |
| */ |
| if( ( ret = asn1_get_tag( &p, end, &len, |
| ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 ) |
| return( ret ); |
| |
| end_curve = p + len; |
| |
| /* |
| * FieldElement ::= OCTET STRING |
| * containing an integer in the case of a prime field |
| */ |
| if( ( ret = asn1_get_tag( &p, end_curve, &len, ASN1_OCTET_STRING ) ) != 0 || |
| ( ret = mpi_read_binary( &grp->A, p, len ) ) != 0 ) |
| { |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| } |
| |
| p += len; |
| |
| if( ( ret = asn1_get_tag( &p, end_curve, &len, ASN1_OCTET_STRING ) ) != 0 || |
| ( ret = mpi_read_binary( &grp->B, p, len ) ) != 0 ) |
| { |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| } |
| |
| p += len; |
| |
| /* Ignore seed BIT STRING OPTIONAL */ |
| if( ( ret = asn1_get_tag( &p, end_curve, &len, ASN1_BIT_STRING ) ) == 0 ) |
| p += len; |
| |
| if( p != end_curve ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + |
| POLARSSL_ERR_ASN1_LENGTH_MISMATCH ); |
| |
| /* |
| * ECPoint ::= OCTET STRING |
| */ |
| if( ( ret = asn1_get_tag( &p, end, &len, ASN1_OCTET_STRING ) ) != 0 ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| |
| if( ( ret = ecp_point_read_binary( grp, &grp->G, |
| ( const unsigned char *) p, len ) ) != 0 ) |
| { |
| /* |
| * If we can't read the point because it's compressed, cheat by |
| * reading only the X coordinate and the parity bit of Y. |
| */ |
| if( ret != POLARSSL_ERR_ECP_FEATURE_UNAVAILABLE || |
| ( p[0] != 0x02 && p[0] != 0x03 ) || |
| len != mpi_size( &grp->P ) + 1 || |
| mpi_read_binary( &grp->G.X, p + 1, len - 1 ) != 0 || |
| mpi_lset( &grp->G.Y, p[0] - 2 ) != 0 || |
| mpi_lset( &grp->G.Z, 1 ) != 0 ) |
| { |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT ); |
| } |
| } |
| |
| p += len; |
| |
| /* |
| * order INTEGER |
| */ |
| if( ( ret = asn1_get_mpi( &p, end, &grp->N ) ) ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| |
| grp->nbits = mpi_msb( &grp->N ); |
| |
| /* |
| * Allow optional elements by purposefully not enforcing p == end here. |
| */ |
| |
| return( 0 ); |
| } |
| |
| /* |
| * Find the group id associated with an (almost filled) group as generated by |
| * pk_group_from_specified(), or return an error if unknown. |
| */ |
| static int pk_group_id_from_group( const ecp_group *grp, ecp_group_id *grp_id ) |
| { |
| int ret = 0; |
| ecp_group ref; |
| const ecp_group_id *id; |
| |
| ecp_group_init( &ref ); |
| |
| for( id = ecp_grp_id_list(); *id != POLARSSL_ECP_DP_NONE; id++ ) |
| { |
| /* Load the group associated to that id */ |
| ecp_group_free( &ref ); |
| MPI_CHK( ecp_use_known_dp( &ref, *id ) ); |
| |
| /* Compare to the group we were given, starting with easy tests */ |
| if( grp->pbits == ref.pbits && grp->nbits == ref.nbits && |
| mpi_cmp_mpi( &grp->P, &ref.P ) == 0 && |
| mpi_cmp_mpi( &grp->A, &ref.A ) == 0 && |
| mpi_cmp_mpi( &grp->B, &ref.B ) == 0 && |
| mpi_cmp_mpi( &grp->N, &ref.N ) == 0 && |
| mpi_cmp_mpi( &grp->G.X, &ref.G.X ) == 0 && |
| mpi_cmp_mpi( &grp->G.Z, &ref.G.Z ) == 0 && |
| /* For Y we may only know the parity bit, so compare only that */ |
| mpi_get_bit( &grp->G.Y, 0 ) == mpi_get_bit( &ref.G.Y, 0 ) ) |
| { |
| break; |
| } |
| |
| } |
| |
| cleanup: |
| ecp_group_free( &ref ); |
| |
| *grp_id = *id; |
| |
| if( ret == 0 && *id == POLARSSL_ECP_DP_NONE ) |
| ret = POLARSSL_ERR_ECP_FEATURE_UNAVAILABLE; |
| |
| return( ret ); |
| } |
| |
| /* |
| * Parse a SpecifiedECDomain (SEC 1 C.2) and find the associated group ID |
| */ |
| static int pk_group_id_from_specified( const asn1_buf *params, |
| ecp_group_id *grp_id ) |
| { |
| int ret; |
| ecp_group grp; |
| |
| ecp_group_init( &grp ); |
| |
| if( ( ret = pk_group_from_specified( params, &grp ) ) != 0 ) |
| goto cleanup; |
| |
| ret = pk_group_id_from_group( &grp, grp_id ); |
| |
| cleanup: |
| ecp_group_free( &grp ); |
| |
| return( ret ); |
| } |
| #endif /* POLARSSL_PK_PARSE_EC_EXTENDED */ |
| |
| /* |
| * Use EC parameters to initialise an EC group |
| * |
| * ECParameters ::= CHOICE { |
| * namedCurve OBJECT IDENTIFIER |
| * specifiedCurve SpecifiedECDomain -- = SEQUENCE { ... } |
| * -- implicitCurve NULL |
| */ |
| static int pk_use_ecparams( const asn1_buf *params, ecp_group *grp ) |
| { |
| int ret; |
| ecp_group_id grp_id; |
| |
| if( params->tag == ASN1_OID ) |
| { |
| if( oid_get_ec_grp( params, &grp_id ) != 0 ) |
| return( POLARSSL_ERR_PK_UNKNOWN_NAMED_CURVE ); |
| } |
| else |
| { |
| #if defined(POLARSSL_PK_PARSE_EC_EXTENDED) |
| if( ( ret = pk_group_id_from_specified( params, &grp_id ) ) != 0 ) |
| return( ret ); |
| #else |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT ); |
| #endif |
| } |
| |
| /* |
| * grp may already be initilialized; if so, make sure IDs match |
| */ |
| if( grp->id != POLARSSL_ECP_DP_NONE && grp->id != grp_id ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT ); |
| |
| if( ( ret = ecp_use_known_dp( grp, grp_id ) ) != 0 ) |
| return( ret ); |
| |
| return( 0 ); |
| } |
| |
| /* |
| * EC public key is an EC point |
| * |
| * The caller is responsible for clearing the structure upon failure if |
| * desired. Take care to pass along the possible ECP_FEATURE_UNAVAILABLE |
| * return code of ecp_point_read_binary() and leave p in a usable state. |
| */ |
| static int pk_get_ecpubkey( unsigned char **p, const unsigned char *end, |
| ecp_keypair *key ) |
| { |
| int ret; |
| |
| if( ( ret = ecp_point_read_binary( &key->grp, &key->Q, |
| (const unsigned char *) *p, end - *p ) ) == 0 ) |
| { |
| ret = ecp_check_pubkey( &key->grp, &key->Q ); |
| } |
| |
| /* |
| * We know ecp_point_read_binary consumed all bytes or failed |
| */ |
| *p = (unsigned char *) end; |
| |
| return( ret ); |
| } |
| #endif /* POLARSSL_ECP_C */ |
| |
| #if defined(POLARSSL_RSA_C) |
| /* |
| * RSAPublicKey ::= SEQUENCE { |
| * modulus INTEGER, -- n |
| * publicExponent INTEGER -- e |
| * } |
| */ |
| static int pk_get_rsapubkey( unsigned char **p, |
| const unsigned char *end, |
| rsa_context *rsa ) |
| { |
| int ret; |
| size_t len; |
| |
| if( ( ret = asn1_get_tag( p, end, &len, |
| ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 ) |
| return( POLARSSL_ERR_PK_INVALID_PUBKEY + ret ); |
| |
| if( *p + len != end ) |
| return( POLARSSL_ERR_PK_INVALID_PUBKEY + |
| POLARSSL_ERR_ASN1_LENGTH_MISMATCH ); |
| |
| if( ( ret = asn1_get_mpi( p, end, &rsa->N ) ) != 0 || |
| ( ret = asn1_get_mpi( p, end, &rsa->E ) ) != 0 ) |
| return( POLARSSL_ERR_PK_INVALID_PUBKEY + ret ); |
| |
| if( *p != end ) |
| return( POLARSSL_ERR_PK_INVALID_PUBKEY + |
| POLARSSL_ERR_ASN1_LENGTH_MISMATCH ); |
| |
| if( ( ret = rsa_check_pubkey( rsa ) ) != 0 ) |
| return( POLARSSL_ERR_PK_INVALID_PUBKEY ); |
| |
| rsa->len = mpi_size( &rsa->N ); |
| |
| return( 0 ); |
| } |
| #endif /* POLARSSL_RSA_C */ |
| |
| /* Get a PK algorithm identifier |
| * |
| * AlgorithmIdentifier ::= SEQUENCE { |
| * algorithm OBJECT IDENTIFIER, |
| * parameters ANY DEFINED BY algorithm OPTIONAL } |
| */ |
| static int pk_get_pk_alg( unsigned char **p, |
| const unsigned char *end, |
| pk_type_t *pk_alg, asn1_buf *params ) |
| { |
| int ret; |
| asn1_buf alg_oid; |
| |
| memset( params, 0, sizeof(asn1_buf) ); |
| |
| if( ( ret = asn1_get_alg( p, end, &alg_oid, params ) ) != 0 ) |
| return( POLARSSL_ERR_PK_INVALID_ALG + ret ); |
| |
| if( oid_get_pk_alg( &alg_oid, pk_alg ) != 0 ) |
| return( POLARSSL_ERR_PK_UNKNOWN_PK_ALG ); |
| |
| /* |
| * No parameters with RSA (only for EC) |
| */ |
| if( *pk_alg == POLARSSL_PK_RSA && |
| ( ( params->tag != ASN1_NULL && params->tag != 0 ) || |
| params->len != 0 ) ) |
| { |
| return( POLARSSL_ERR_PK_INVALID_ALG ); |
| } |
| |
| return( 0 ); |
| } |
| |
| /* |
| * SubjectPublicKeyInfo ::= SEQUENCE { |
| * algorithm AlgorithmIdentifier, |
| * subjectPublicKey BIT STRING } |
| */ |
| int pk_parse_subpubkey( unsigned char **p, const unsigned char *end, |
| pk_context *pk ) |
| { |
| int ret; |
| size_t len; |
| asn1_buf alg_params; |
| pk_type_t pk_alg = POLARSSL_PK_NONE; |
| const pk_info_t *pk_info; |
| |
| if( ( ret = asn1_get_tag( p, end, &len, |
| ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 ) |
| { |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| } |
| |
| end = *p + len; |
| |
| if( ( ret = pk_get_pk_alg( p, end, &pk_alg, &alg_params ) ) != 0 ) |
| return( ret ); |
| |
| if( ( ret = asn1_get_bitstring_null( p, end, &len ) ) != 0 ) |
| return( POLARSSL_ERR_PK_INVALID_PUBKEY + ret ); |
| |
| if( *p + len != end ) |
| return( POLARSSL_ERR_PK_INVALID_PUBKEY + |
| POLARSSL_ERR_ASN1_LENGTH_MISMATCH ); |
| |
| if( ( pk_info = pk_info_from_type( pk_alg ) ) == NULL ) |
| return( POLARSSL_ERR_PK_UNKNOWN_PK_ALG ); |
| |
| if( ( ret = pk_init_ctx( pk, pk_info ) ) != 0 ) |
| return( ret ); |
| |
| #if defined(POLARSSL_RSA_C) |
| if( pk_alg == POLARSSL_PK_RSA ) |
| { |
| ret = pk_get_rsapubkey( p, end, pk_rsa( *pk ) ); |
| } else |
| #endif /* POLARSSL_RSA_C */ |
| #if defined(POLARSSL_ECP_C) |
| if( pk_alg == POLARSSL_PK_ECKEY_DH || pk_alg == POLARSSL_PK_ECKEY ) |
| { |
| ret = pk_use_ecparams( &alg_params, &pk_ec( *pk )->grp ); |
| if( ret == 0 ) |
| ret = pk_get_ecpubkey( p, end, pk_ec( *pk ) ); |
| } else |
| #endif /* POLARSSL_ECP_C */ |
| ret = POLARSSL_ERR_PK_UNKNOWN_PK_ALG; |
| |
| if( ret == 0 && *p != end ) |
| ret = POLARSSL_ERR_PK_INVALID_PUBKEY |
| POLARSSL_ERR_ASN1_LENGTH_MISMATCH; |
| |
| if( ret != 0 ) |
| pk_free( pk ); |
| |
| return( ret ); |
| } |
| |
| #if defined(POLARSSL_RSA_C) |
| /* |
| * Parse a PKCS#1 encoded private RSA key |
| */ |
| static int pk_parse_key_pkcs1_der( rsa_context *rsa, |
| const unsigned char *key, |
| size_t keylen ) |
| { |
| int ret; |
| size_t len; |
| unsigned char *p, *end; |
| |
| p = (unsigned char *) key; |
| end = p + keylen; |
| |
| /* |
| * This function parses the RSAPrivateKey (PKCS#1) |
| * |
| * RSAPrivateKey ::= SEQUENCE { |
| * version Version, |
| * modulus INTEGER, -- n |
| * publicExponent INTEGER, -- e |
| * privateExponent INTEGER, -- d |
| * prime1 INTEGER, -- p |
| * prime2 INTEGER, -- q |
| * exponent1 INTEGER, -- d mod (p-1) |
| * exponent2 INTEGER, -- d mod (q-1) |
| * coefficient INTEGER, -- (inverse of q) mod p |
| * otherPrimeInfos OtherPrimeInfos OPTIONAL |
| * } |
| */ |
| if( ( ret = asn1_get_tag( &p, end, &len, |
| ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 ) |
| { |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| } |
| |
| end = p + len; |
| |
| if( ( ret = asn1_get_int( &p, end, &rsa->ver ) ) != 0 ) |
| { |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| } |
| |
| if( rsa->ver != 0 ) |
| { |
| return( POLARSSL_ERR_PK_KEY_INVALID_VERSION ); |
| } |
| |
| if( ( ret = asn1_get_mpi( &p, end, &rsa->N ) ) != 0 || |
| ( ret = asn1_get_mpi( &p, end, &rsa->E ) ) != 0 || |
| ( ret = asn1_get_mpi( &p, end, &rsa->D ) ) != 0 || |
| ( ret = asn1_get_mpi( &p, end, &rsa->P ) ) != 0 || |
| ( ret = asn1_get_mpi( &p, end, &rsa->Q ) ) != 0 || |
| ( ret = asn1_get_mpi( &p, end, &rsa->DP ) ) != 0 || |
| ( ret = asn1_get_mpi( &p, end, &rsa->DQ ) ) != 0 || |
| ( ret = asn1_get_mpi( &p, end, &rsa->QP ) ) != 0 ) |
| { |
| rsa_free( rsa ); |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| } |
| |
| rsa->len = mpi_size( &rsa->N ); |
| |
| if( p != end ) |
| { |
| rsa_free( rsa ); |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + |
| POLARSSL_ERR_ASN1_LENGTH_MISMATCH ); |
| } |
| |
| if( ( ret = rsa_check_privkey( rsa ) ) != 0 ) |
| { |
| rsa_free( rsa ); |
| return( ret ); |
| } |
| |
| return( 0 ); |
| } |
| #endif /* POLARSSL_RSA_C */ |
| |
| #if defined(POLARSSL_ECP_C) |
| /* |
| * Parse a SEC1 encoded private EC key |
| */ |
| static int pk_parse_key_sec1_der( ecp_keypair *eck, |
| const unsigned char *key, |
| size_t keylen ) |
| { |
| int ret; |
| int version, pubkey_done; |
| size_t len; |
| asn1_buf params; |
| unsigned char *p = (unsigned char *) key; |
| unsigned char *end = p + keylen; |
| unsigned char *end2; |
| |
| /* |
| * RFC 5915, or SEC1 Appendix C.4 |
| * |
| * ECPrivateKey ::= SEQUENCE { |
| * version INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1), |
| * privateKey OCTET STRING, |
| * parameters [0] ECParameters {{ NamedCurve }} OPTIONAL, |
| * publicKey [1] BIT STRING OPTIONAL |
| * } |
| */ |
| if( ( ret = asn1_get_tag( &p, end, &len, |
| ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 ) |
| { |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| } |
| |
| end = p + len; |
| |
| if( ( ret = asn1_get_int( &p, end, &version ) ) != 0 ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| |
| if( version != 1 ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_VERSION ); |
| |
| if( ( ret = asn1_get_tag( &p, end, &len, ASN1_OCTET_STRING ) ) != 0 ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| |
| if( ( ret = mpi_read_binary( &eck->d, p, len ) ) != 0 ) |
| { |
| ecp_keypair_free( eck ); |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| } |
| |
| p += len; |
| |
| /* |
| * Is 'parameters' present? |
| */ |
| if( ( ret = asn1_get_tag( &p, end, &len, |
| ASN1_CONTEXT_SPECIFIC | ASN1_CONSTRUCTED | 0 ) ) == 0 ) |
| { |
| if( ( ret = pk_get_ecparams( &p, p + len, ¶ms) ) != 0 || |
| ( ret = pk_use_ecparams( ¶ms, &eck->grp ) ) != 0 ) |
| { |
| ecp_keypair_free( eck ); |
| return( ret ); |
| } |
| } |
| else if( ret != POLARSSL_ERR_ASN1_UNEXPECTED_TAG ) |
| { |
| ecp_keypair_free( eck ); |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| } |
| |
| /* |
| * Is 'publickey' present? If not, or if we can't read it (eg because it |
| * is compressed), create it from the private key. |
| */ |
| pubkey_done = 0; |
| if( ( ret = asn1_get_tag( &p, end, &len, |
| ASN1_CONTEXT_SPECIFIC | ASN1_CONSTRUCTED | 1 ) ) == 0 ) |
| { |
| end2 = p + len; |
| |
| if( ( ret = asn1_get_bitstring_null( &p, end2, &len ) ) != 0 ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| |
| if( p + len != end2 ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + |
| POLARSSL_ERR_ASN1_LENGTH_MISMATCH ); |
| |
| if( ( ret = pk_get_ecpubkey( &p, end2, eck ) ) == 0 ) |
| pubkey_done = 1; |
| else |
| { |
| /* |
| * The only acceptable failure mode of pk_get_ecpubkey() above |
| * is if the point format is not recognized. |
| */ |
| if( ret != POLARSSL_ERR_ECP_FEATURE_UNAVAILABLE ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT ); |
| } |
| } |
| else if( ret != POLARSSL_ERR_ASN1_UNEXPECTED_TAG ) |
| { |
| ecp_keypair_free( eck ); |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| } |
| |
| if( ! pubkey_done && |
| ( ret = ecp_mul( &eck->grp, &eck->Q, &eck->d, &eck->grp.G, |
| NULL, NULL ) ) != 0 ) |
| { |
| ecp_keypair_free( eck ); |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| } |
| |
| if( ( ret = ecp_check_privkey( &eck->grp, &eck->d ) ) != 0 ) |
| { |
| ecp_keypair_free( eck ); |
| return( ret ); |
| } |
| |
| return( 0 ); |
| } |
| #endif /* POLARSSL_ECP_C */ |
| |
| /* |
| * Parse an unencrypted PKCS#8 encoded private key |
| */ |
| static int pk_parse_key_pkcs8_unencrypted_der( |
| pk_context *pk, |
| const unsigned char* key, |
| size_t keylen ) |
| { |
| int ret, version; |
| size_t len; |
| asn1_buf params; |
| unsigned char *p = (unsigned char *) key; |
| unsigned char *end = p + keylen; |
| pk_type_t pk_alg = POLARSSL_PK_NONE; |
| const pk_info_t *pk_info; |
| |
| /* |
| * This function parses the PrivatKeyInfo object (PKCS#8 v1.2 = RFC 5208) |
| * |
| * PrivateKeyInfo ::= SEQUENCE { |
| * version Version, |
| * privateKeyAlgorithm PrivateKeyAlgorithmIdentifier, |
| * privateKey PrivateKey, |
| * attributes [0] IMPLICIT Attributes OPTIONAL } |
| * |
| * Version ::= INTEGER |
| * PrivateKeyAlgorithmIdentifier ::= AlgorithmIdentifier |
| * PrivateKey ::= OCTET STRING |
| * |
| * The PrivateKey OCTET STRING is a SEC1 ECPrivateKey |
| */ |
| |
| if( ( ret = asn1_get_tag( &p, end, &len, |
| ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 ) |
| { |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| } |
| |
| end = p + len; |
| |
| if( ( ret = asn1_get_int( &p, end, &version ) ) != 0 ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| |
| if( version != 0 ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_VERSION + ret ); |
| |
| if( ( ret = pk_get_pk_alg( &p, end, &pk_alg, ¶ms ) ) != 0 ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| |
| if( ( ret = asn1_get_tag( &p, end, &len, ASN1_OCTET_STRING ) ) != 0 ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| |
| if( len < 1 ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + |
| POLARSSL_ERR_ASN1_OUT_OF_DATA ); |
| |
| if( ( pk_info = pk_info_from_type( pk_alg ) ) == NULL ) |
| return( POLARSSL_ERR_PK_UNKNOWN_PK_ALG ); |
| |
| if( ( ret = pk_init_ctx( pk, pk_info ) ) != 0 ) |
| return( ret ); |
| |
| #if defined(POLARSSL_RSA_C) |
| if( pk_alg == POLARSSL_PK_RSA ) |
| { |
| if( ( ret = pk_parse_key_pkcs1_der( pk_rsa( *pk ), p, len ) ) != 0 ) |
| { |
| pk_free( pk ); |
| return( ret ); |
| } |
| } else |
| #endif /* POLARSSL_RSA_C */ |
| #if defined(POLARSSL_ECP_C) |
| if( pk_alg == POLARSSL_PK_ECKEY || pk_alg == POLARSSL_PK_ECKEY_DH ) |
| { |
| if( ( ret = pk_use_ecparams( ¶ms, &pk_ec( *pk )->grp ) ) != 0 || |
| ( ret = pk_parse_key_sec1_der( pk_ec( *pk ), p, len ) ) != 0 ) |
| { |
| pk_free( pk ); |
| return( ret ); |
| } |
| } else |
| #endif /* POLARSSL_ECP_C */ |
| return( POLARSSL_ERR_PK_UNKNOWN_PK_ALG ); |
| |
| return( 0 ); |
| } |
| |
| /* |
| * Parse an encrypted PKCS#8 encoded private key |
| */ |
| static int pk_parse_key_pkcs8_encrypted_der( |
| pk_context *pk, |
| const unsigned char *key, size_t keylen, |
| const unsigned char *pwd, size_t pwdlen ) |
| { |
| int ret, decrypted = 0; |
| size_t len; |
| unsigned char buf[2048]; |
| unsigned char *p, *end; |
| asn1_buf pbe_alg_oid, pbe_params; |
| #if defined(POLARSSL_PKCS12_C) |
| cipher_type_t cipher_alg; |
| md_type_t md_alg; |
| #endif |
| |
| memset( buf, 0, sizeof( buf ) ); |
| |
| p = (unsigned char *) key; |
| end = p + keylen; |
| |
| if( pwdlen == 0 ) |
| return( POLARSSL_ERR_PK_PASSWORD_REQUIRED ); |
| |
| /* |
| * This function parses the EncryptedPrivatKeyInfo object (PKCS#8) |
| * |
| * EncryptedPrivateKeyInfo ::= SEQUENCE { |
| * encryptionAlgorithm EncryptionAlgorithmIdentifier, |
| * encryptedData EncryptedData |
| * } |
| * |
| * EncryptionAlgorithmIdentifier ::= AlgorithmIdentifier |
| * |
| * EncryptedData ::= OCTET STRING |
| * |
| * The EncryptedData OCTET STRING is a PKCS#8 PrivateKeyInfo |
| */ |
| if( ( ret = asn1_get_tag( &p, end, &len, |
| ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 ) |
| { |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| } |
| |
| end = p + len; |
| |
| if( ( ret = asn1_get_alg( &p, end, &pbe_alg_oid, &pbe_params ) ) != 0 ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| |
| if( ( ret = asn1_get_tag( &p, end, &len, ASN1_OCTET_STRING ) ) != 0 ) |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT + ret ); |
| |
| if( len > sizeof( buf ) ) |
| return( POLARSSL_ERR_PK_BAD_INPUT_DATA ); |
| |
| /* |
| * Decrypt EncryptedData with appropriate PDE |
| */ |
| #if defined(POLARSSL_PKCS12_C) |
| if( oid_get_pkcs12_pbe_alg( &pbe_alg_oid, &md_alg, &cipher_alg ) == 0 ) |
| { |
| if( ( ret = pkcs12_pbe( &pbe_params, PKCS12_PBE_DECRYPT, |
| cipher_alg, md_alg, |
| pwd, pwdlen, p, len, buf ) ) != 0 ) |
| { |
| if( ret == POLARSSL_ERR_PKCS12_PASSWORD_MISMATCH ) |
| return( POLARSSL_ERR_PK_PASSWORD_MISMATCH ); |
| |
| return( ret ); |
| } |
| |
| decrypted = 1; |
| } |
| else if( OID_CMP( OID_PKCS12_PBE_SHA1_RC4_128, &pbe_alg_oid ) ) |
| { |
| if( ( ret = pkcs12_pbe_sha1_rc4_128( &pbe_params, |
| PKCS12_PBE_DECRYPT, |
| pwd, pwdlen, |
| p, len, buf ) ) != 0 ) |
| { |
| return( ret ); |
| } |
| |
| // Best guess for password mismatch when using RC4. If first tag is |
| // not ASN1_CONSTRUCTED | ASN1_SEQUENCE |
| // |
| if( *buf != ( ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) |
| return( POLARSSL_ERR_PK_PASSWORD_MISMATCH ); |
| |
| decrypted = 1; |
| } |
| else |
| #endif /* POLARSSL_PKCS12_C */ |
| #if defined(POLARSSL_PKCS5_C) |
| if( OID_CMP( OID_PKCS5_PBES2, &pbe_alg_oid ) ) |
| { |
| if( ( ret = pkcs5_pbes2( &pbe_params, PKCS5_DECRYPT, pwd, pwdlen, |
| p, len, buf ) ) != 0 ) |
| { |
| if( ret == POLARSSL_ERR_PKCS5_PASSWORD_MISMATCH ) |
| return( POLARSSL_ERR_PK_PASSWORD_MISMATCH ); |
| |
| return( ret ); |
| } |
| |
| decrypted = 1; |
| } |
| else |
| #endif /* POLARSSL_PKCS5_C */ |
| { |
| ((void) pwd); |
| } |
| |
| if( decrypted == 0 ) |
| return( POLARSSL_ERR_PK_FEATURE_UNAVAILABLE ); |
| |
| return( pk_parse_key_pkcs8_unencrypted_der( pk, buf, len ) ); |
| } |
| |
| /* |
| * Parse a private key |
| */ |
| int pk_parse_key( pk_context *pk, |
| const unsigned char *key, size_t keylen, |
| const unsigned char *pwd, size_t pwdlen ) |
| { |
| int ret; |
| const pk_info_t *pk_info; |
| |
| #if defined(POLARSSL_PEM_PARSE_C) |
| size_t len; |
| pem_context pem; |
| |
| pem_init( &pem ); |
| |
| #if defined(POLARSSL_RSA_C) |
| ret = pem_read_buffer( &pem, |
| "-----BEGIN RSA PRIVATE KEY-----", |
| "-----END RSA PRIVATE KEY-----", |
| key, pwd, pwdlen, &len ); |
| if( ret == 0 ) |
| { |
| if( ( pk_info = pk_info_from_type( POLARSSL_PK_RSA ) ) == NULL ) |
| return( POLARSSL_ERR_PK_UNKNOWN_PK_ALG ); |
| |
| if( ( ret = pk_init_ctx( pk, pk_info ) ) != 0 || |
| ( ret = pk_parse_key_pkcs1_der( pk_rsa( *pk ), |
| pem.buf, pem.buflen ) ) != 0 ) |
| { |
| pk_free( pk ); |
| } |
| |
| pem_free( &pem ); |
| return( ret ); |
| } |
| else if( ret == POLARSSL_ERR_PEM_PASSWORD_MISMATCH ) |
| return( POLARSSL_ERR_PK_PASSWORD_MISMATCH ); |
| else if( ret == POLARSSL_ERR_PEM_PASSWORD_REQUIRED ) |
| return( POLARSSL_ERR_PK_PASSWORD_REQUIRED ); |
| else if( ret != POLARSSL_ERR_PEM_NO_HEADER_FOOTER_PRESENT ) |
| return( ret ); |
| #endif /* POLARSSL_RSA_C */ |
| |
| #if defined(POLARSSL_ECP_C) |
| ret = pem_read_buffer( &pem, |
| "-----BEGIN EC PRIVATE KEY-----", |
| "-----END EC PRIVATE KEY-----", |
| key, pwd, pwdlen, &len ); |
| if( ret == 0 ) |
| { |
| if( ( pk_info = pk_info_from_type( POLARSSL_PK_ECKEY ) ) == NULL ) |
| return( POLARSSL_ERR_PK_UNKNOWN_PK_ALG ); |
| |
| if( ( ret = pk_init_ctx( pk, pk_info ) ) != 0 || |
| ( ret = pk_parse_key_sec1_der( pk_ec( *pk ), |
| pem.buf, pem.buflen ) ) != 0 ) |
| { |
| pk_free( pk ); |
| } |
| |
| pem_free( &pem ); |
| return( ret ); |
| } |
| else if( ret == POLARSSL_ERR_PEM_PASSWORD_MISMATCH ) |
| return( POLARSSL_ERR_PK_PASSWORD_MISMATCH ); |
| else if( ret == POLARSSL_ERR_PEM_PASSWORD_REQUIRED ) |
| return( POLARSSL_ERR_PK_PASSWORD_REQUIRED ); |
| else if( ret != POLARSSL_ERR_PEM_NO_HEADER_FOOTER_PRESENT ) |
| return( ret ); |
| #endif /* POLARSSL_ECP_C */ |
| |
| ret = pem_read_buffer( &pem, |
| "-----BEGIN PRIVATE KEY-----", |
| "-----END PRIVATE KEY-----", |
| key, NULL, 0, &len ); |
| if( ret == 0 ) |
| { |
| if( ( ret = pk_parse_key_pkcs8_unencrypted_der( pk, |
| pem.buf, pem.buflen ) ) != 0 ) |
| { |
| pk_free( pk ); |
| } |
| |
| pem_free( &pem ); |
| return( ret ); |
| } |
| else if( ret != POLARSSL_ERR_PEM_NO_HEADER_FOOTER_PRESENT ) |
| return( ret ); |
| |
| ret = pem_read_buffer( &pem, |
| "-----BEGIN ENCRYPTED PRIVATE KEY-----", |
| "-----END ENCRYPTED PRIVATE KEY-----", |
| key, NULL, 0, &len ); |
| if( ret == 0 ) |
| { |
| if( ( ret = pk_parse_key_pkcs8_encrypted_der( pk, |
| pem.buf, pem.buflen, |
| pwd, pwdlen ) ) != 0 ) |
| { |
| pk_free( pk ); |
| } |
| |
| pem_free( &pem ); |
| return( ret ); |
| } |
| else if( ret != POLARSSL_ERR_PEM_NO_HEADER_FOOTER_PRESENT ) |
| return( ret ); |
| #else |
| ((void) pwd); |
| ((void) pwdlen); |
| #endif /* POLARSSL_PEM_PARSE_C */ |
| |
| /* |
| * At this point we only know it's not a PEM formatted key. Could be any |
| * of the known DER encoded private key formats |
| * |
| * We try the different DER format parsers to see if one passes without |
| * error |
| */ |
| if( ( ret = pk_parse_key_pkcs8_encrypted_der( pk, key, keylen, |
| pwd, pwdlen ) ) == 0 ) |
| { |
| return( 0 ); |
| } |
| |
| pk_free( pk ); |
| |
| if( ret == POLARSSL_ERR_PK_PASSWORD_MISMATCH ) |
| { |
| return( ret ); |
| } |
| |
| if( ( ret = pk_parse_key_pkcs8_unencrypted_der( pk, key, keylen ) ) == 0 ) |
| return( 0 ); |
| |
| pk_free( pk ); |
| |
| #if defined(POLARSSL_RSA_C) |
| if( ( pk_info = pk_info_from_type( POLARSSL_PK_RSA ) ) == NULL ) |
| return( POLARSSL_ERR_PK_UNKNOWN_PK_ALG ); |
| |
| if( ( ret = pk_init_ctx( pk, pk_info ) ) != 0 || |
| ( ret = pk_parse_key_pkcs1_der( pk_rsa( *pk ), key, keylen ) ) == 0 ) |
| { |
| return( 0 ); |
| } |
| |
| pk_free( pk ); |
| #endif /* POLARSSL_RSA_C */ |
| |
| #if defined(POLARSSL_ECP_C) |
| if( ( pk_info = pk_info_from_type( POLARSSL_PK_ECKEY ) ) == NULL ) |
| return( POLARSSL_ERR_PK_UNKNOWN_PK_ALG ); |
| |
| if( ( ret = pk_init_ctx( pk, pk_info ) ) != 0 || |
| ( ret = pk_parse_key_sec1_der( pk_ec( *pk ), key, keylen ) ) == 0 ) |
| { |
| return( 0 ); |
| } |
| |
| pk_free( pk ); |
| #endif /* POLARSSL_ECP_C */ |
| |
| return( POLARSSL_ERR_PK_KEY_INVALID_FORMAT ); |
| } |
| |
| /* |
| * Parse a public key |
| */ |
| int pk_parse_public_key( pk_context *ctx, |
| const unsigned char *key, size_t keylen ) |
| { |
| int ret; |
| unsigned char *p; |
| #if defined(POLARSSL_PEM_PARSE_C) |
| size_t len; |
| pem_context pem; |
| |
| pem_init( &pem ); |
| ret = pem_read_buffer( &pem, |
| "-----BEGIN PUBLIC KEY-----", |
| "-----END PUBLIC KEY-----", |
| key, NULL, 0, &len ); |
| |
| if( ret == 0 ) |
| { |
| /* |
| * Was PEM encoded |
| */ |
| key = pem.buf; |
| keylen = pem.buflen; |
| } |
| else if( ret != POLARSSL_ERR_PEM_NO_HEADER_FOOTER_PRESENT ) |
| { |
| pem_free( &pem ); |
| return( ret ); |
| } |
| #endif /* POLARSSL_PEM_PARSE_C */ |
| p = (unsigned char *) key; |
| |
| ret = pk_parse_subpubkey( &p, p + keylen, ctx ); |
| |
| #if defined(POLARSSL_PEM_PARSE_C) |
| pem_free( &pem ); |
| #endif |
| |
| return( ret ); |
| } |
| |
| #endif /* POLARSSL_PK_PARSE_C */ |