diff options
Diffstat (limited to '')
| -rw-r--r-- | g10/seskey.c | 54 |
1 files changed, 49 insertions, 5 deletions
diff --git a/g10/seskey.c b/g10/seskey.c index 325234c45..7d3cba27b 100644 --- a/g10/seskey.c +++ b/g10/seskey.c @@ -103,13 +103,14 @@ encode_session_key( DEK *dek, unsigned nbits ) /**************** * Encode a ripemd160 message digest of LEN bytes into NBITS. * returns: A mpi with the session key (caller must free) + * RMD160 Object ID is 1.3.36.3.2.1 */ MPI encode_rmd160_value( byte *md, unsigned len, unsigned nbits ) { - static byte asn[18] = /* FIXME: need other values*/ - { 0x30, 0x20, 0x30, 0x0c, 0x06, 0x08, 0x2a, 0x86,0x48, - 0x86, 0xf7, 0x0d, 0x02, 0x05, 0x05, 0x00, 0x04, 0x10 }; + static byte asn[15] = + { 0x30, 0x21, 0x30, 0x09, 0x06, 0x05, 0x2b, 0x24, 0x03, + 0x02, 0x01, 0x05, 0x00, 0x04, 0x14 }; int nframe = (nbits+7) / 8; byte *p; MPI frame; @@ -120,7 +121,7 @@ encode_rmd160_value( byte *md, unsigned len, unsigned nbits ) /* We encode the MD in this way: * - * 0 A PAD(n bytes) 0 ASN(18 bytes) MD(20 bytes) + * 0 A PAD(n bytes) 0 ASN(15 bytes) MD(20 bytes) * * PAD consists of FF bytes. */ @@ -128,7 +129,47 @@ encode_rmd160_value( byte *md, unsigned len, unsigned nbits ) n = 0; for(i=20-1; i >= 0; i--, n++ ) mpi_putbyte(frame, n, md[i] ); - for( i=18-1; i >= 0; i--, n++ ) + for( i=15-1; i >= 0; i--, n++ ) + mpi_putbyte(frame, n, asn[i] ); + mpi_putbyte(frame, n++, 0 ); + while( n < nframe-2 ) + mpi_putbyte(frame, n++, 0xff ); + mpi_putbyte(frame, n++, DIGEST_ALGO_RMD160 ); + mpi_putbyte(frame, n++, 0 ); + assert( n == nframe ); + return frame; +} + +/**************** + * Encode a sha-1 message digest of LEN bytes into NBITS. + * returns: A mpi with the session key (caller must free) + * SHA-1 Objet ID is 1.3.14.3.2.26 + */ +MPI +encode_sha1_value( byte *md, unsigned len, unsigned nbits ) +{ + static byte asn[15] = + { 0x30, 0x21, 0x30, 0x09, 0x06, 0x05, 0x2b, 0x0e, 0x03, + 0x02, 0x1a, 0x05, 0x00, 0x04, 0x14 }; + int nframe = (nbits+7) / 8; + byte *p; + MPI frame; + int i,n,c; + + if( (nbits % BITS_PER_MPI_LIMB) || nframe < 42 || len != 20 ) + log_bug("can't encode a %d bit MD into a %d bits frame\n",len*8, nbits); + + /* We encode the MD in this way: + * + * 0 A PAD(n bytes) 0 ASN(15 bytes) MD(20 bytes) + * + * PAD consists of FF bytes. + */ + frame = mpi_alloc_secure( nframe / BYTES_PER_MPI_LIMB ); + n = 0; + for(i=20-1; i >= 0; i--, n++ ) + mpi_putbyte(frame, n, md[i] ); + for( i=15-1; i >= 0; i--, n++ ) mpi_putbyte(frame, n, asn[i] ); mpi_putbyte(frame, n++, 0 ); while( n < nframe-2 ) @@ -143,6 +184,7 @@ encode_rmd160_value( byte *md, unsigned len, unsigned nbits ) /**************** * Encode a md5 message digest of LEN bytes into NBITS. * returns: A mpi with the session key (caller must free) + * MD5 Object ID is 1.2.840.113549.2.5 */ MPI encode_md5_value( byte *md, unsigned len, unsigned nbits ) @@ -187,6 +229,8 @@ encode_md_value( MD_HANDLE *md, unsigned nbits ) return encode_md5_value( p, 16, nbits ); else if( md->algo == DIGEST_ALGO_RMD160 ) return encode_rmd160_value( p, 20, nbits ); + else if( md->algo == DIGEST_ALGO_SHA1 ) + return encode_sha1_value( p, 20, nbits ); else log_bug(NULL); } |