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author | Werner Koch <wk@gnupg.org> | 2003-06-18 21:56:13 +0200 |
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committer | Werner Koch <wk@gnupg.org> | 2003-06-18 21:56:13 +0200 |
commit | c0c2c58054923d506f61ce9a71d509b48a381211 (patch) | |
tree | a8f82bffb44eb68eb726ff6db41fa715bcd29193 /g10/seskey.c | |
parent | A small step for GnuPG but a huge leap for error codes. (diff) | |
download | gnupg2-c0c2c58054923d506f61ce9a71d509b48a381211.tar.xz gnupg2-c0c2c58054923d506f61ce9a71d509b48a381211.zip |
Finished the bulk of changes for gnupg 1.9. This included switching
to libgcrypt functions, using shared error codes from libgpg-error,
replacing the old functions we used to have in ../util by those in
../jnlib and ../common, renaming the malloc functions and a couple of
types. Note, that not all changes are listed below becuause they are
too similar and done at far too many places. As of today the code
builds using the current libgcrypt from CVS but it is very unlikely
that it actually works.
Diffstat (limited to 'g10/seskey.c')
-rw-r--r-- | g10/seskey.c | 146 |
1 files changed, 81 insertions, 65 deletions
diff --git a/g10/seskey.c b/g10/seskey.c index fc912eeb5..9eeed2c74 100644 --- a/g10/seskey.c +++ b/g10/seskey.c @@ -1,5 +1,5 @@ /* seskey.c - make sesssion keys etc. - * Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc. + * Copyright (C) 1998, 1999, 2000, 2001, 2003 Free Software Foundation, Inc. * * This file is part of GnuPG. * @@ -23,6 +23,8 @@ #include <stdlib.h> #include <string.h> #include <assert.h> + +#include "gpg.h" #include "util.h" #include "cipher.h" #include "mpi.h" @@ -36,26 +38,35 @@ void make_session_key( DEK *dek ) { - CIPHER_HANDLE chd; - int i, rc; - - dek->keylen = cipher_get_keylen( dek->algo ) / 8; - - chd = cipher_open( dek->algo, CIPHER_MODE_AUTO_CFB, 1 ); - randomize_buffer( dek->key, dek->keylen, 1 ); - for(i=0; i < 16; i++ ) { - rc = cipher_setkey( chd, dek->key, dek->keylen ); - if( !rc ) { - cipher_close( chd ); - return; - } - log_info(_("weak key created - retrying\n") ); - /* Renew the session key until we get a non-weak key. */ - randomize_buffer( dek->key, dek->keylen, 1 ); + gcry_cipher_hd_t chd; + int i, rc; + + dek->keylen = gcry_cipher_get_algo_keylen (dek->algo); + + if (gcry_cipher_open (&chd, dek->algo, GCRY_CIPHER_MODE_CFB, + (GCRY_CIPHER_SECURE + | (dek->algo >= 100 ? + 0 : GCRY_CIPHER_ENABLE_SYNC))) ) + BUG(); + + gcry_randomize (dek->key, dek->keylen, GCRY_STRONG_RANDOM ); + for (i=0; i < 16; i++ ) + { + rc = gcry_cipher_setkey (chd, dek->key, dek->keylen); + if (!rc) + { + gcry_cipher_close (chd); + return; + } + if (gpg_err_code (rc) != GPG_ERR_WEAK_KEY) + BUG(); + log_info (_("weak key created - retrying\n") ); + /* Renew the session key until we get a non-weak key. */ + gcry_randomize (dek->key, dek->keylen, GCRY_STRONG_RANDOM ); } - log_fatal(_( - "cannot avoid weak key for symmetric cipher; tried %d times!\n"), - i); + + log_fatal (_("cannot avoid weak key for symmetric cipher; " + "tried %d times!\n"), i); } @@ -64,15 +75,15 @@ make_session_key( DEK *dek ) * for packing the session key. * returns: A mpi with the session key (caller must free) */ -MPI -encode_session_key( DEK *dek, unsigned nbits ) +gcry_mpi_t +encode_session_key (DEK *dek, unsigned int nbits) { int nframe = (nbits+7) / 8; byte *p; byte *frame; int i,n; u16 csum; - MPI a; + gcry_mpi_t a; /* the current limitation is that we can only use a session key * whose length is a multiple of BITS_PER_MPI_LIMB @@ -99,13 +110,13 @@ encode_session_key( DEK *dek, unsigned nbits ) for( p = dek->key, i=0; i < dek->keylen; i++ ) csum += *p++; - frame = m_alloc_secure( nframe ); + frame = gcry_xmalloc_secure ( nframe ); n = 0; frame[n++] = 0; frame[n++] = 2; i = nframe - 6 - dek->keylen; assert( i > 0 ); - p = get_random_bits( i*8, 1, 1 ); + p = gcry_random_bytes_secure (i, GCRY_STRONG_RANDOM); /* replace zero bytes by new values */ for(;;) { int j, k; @@ -118,14 +129,14 @@ encode_session_key( DEK *dek, unsigned nbits ) if( !k ) break; /* okay: no zero bytes */ k += k/128; /* better get some more */ - pp = get_random_bits( k*8, 1, 1); + pp = gcry_random_bytes_secure( k, GCRY_STRONG_RANDOM); for(j=0; j < i && k ; j++ ) if( !p[j] ) p[j] = pp[--k]; - m_free(pp); + xfree (pp); } memcpy( frame+n, p, i ); - m_free(p); + xfree (p); n += i; frame[n++] = 0; frame[n++] = dek->algo; @@ -133,21 +144,21 @@ encode_session_key( DEK *dek, unsigned nbits ) frame[n++] = csum >>8; frame[n++] = csum; assert( n == nframe ); - a = mpi_alloc_secure( (nframe+BYTES_PER_MPI_LIMB-1) / BYTES_PER_MPI_LIMB ); - mpi_set_buffer( a, frame, nframe, 0 ); - m_free(frame); + if (gcry_mpi_scan( &a, GCRYMPI_FMT_USG, frame, &nframe)) + BUG(); + xfree (frame); return a; } -static MPI -do_encode_md( MD_HANDLE md, int algo, size_t len, unsigned nbits, +static gcry_mpi_t +do_encode_md( gcry_md_hd_t md, int algo, size_t len, unsigned nbits, const byte *asn, size_t asnlen, int v3compathack ) { int nframe = (nbits+7) / 8; byte *frame; int i,n; - MPI a; + gcry_mpi_t a; if( len + asnlen + 4 > nframe ) log_bug("can't encode a %d bit MD into a %d bits frame\n", @@ -159,7 +170,7 @@ do_encode_md( MD_HANDLE md, int algo, size_t len, unsigned nbits, * * PAD consists of FF bytes. */ - frame = md_is_secure(md)? m_alloc_secure( nframe ) : m_alloc( nframe ); + frame = gcry_md_is_secure (md)? xmalloc_secure (nframe): xmalloc (nframe); n = 0; frame[n++] = 0; frame[n++] = v3compathack? algo : 1; /* block type */ @@ -168,13 +179,11 @@ do_encode_md( MD_HANDLE md, int algo, size_t len, unsigned nbits, memset( frame+n, 0xff, i ); n += i; frame[n++] = 0; memcpy( frame+n, asn, asnlen ); n += asnlen; - memcpy( frame+n, md_read(md, algo), len ); n += len; + memcpy( frame+n, gcry_md_read (md, algo), len ); n += len; assert( n == nframe ); - a = md_is_secure(md)? - mpi_alloc_secure( (nframe+BYTES_PER_MPI_LIMB-1) / BYTES_PER_MPI_LIMB ) - : mpi_alloc( (nframe+BYTES_PER_MPI_LIMB-1) / BYTES_PER_MPI_LIMB ); - mpi_set_buffer( a, frame, nframe, 0 ); - m_free(frame); + if (gcry_mpi_scan( &a, GCRYMPI_FMT_USG, frame, &nframe )) + BUG(); + xfree (frame); return a; } @@ -185,33 +194,40 @@ do_encode_md( MD_HANDLE md, int algo, size_t len, unsigned nbits, * which did put the algo identifier inseatd of the block type 1 into * the encoded value. Setting this flag forces the old behaviour. */ -MPI -encode_md_value( int pubkey_algo, MD_HANDLE md, int hash_algo, - unsigned nbits, int v3compathack ) +gcry_mpi_t +encode_md_value (int pubkey_algo, gcry_md_hd_t md, int hash_algo, + unsigned int nbits, int v3compathack ) { - int algo = hash_algo? hash_algo : md_get_algo(md); - const byte *asn; - size_t asnlen, mdlen; - MPI frame; - - if( pubkey_algo == PUBKEY_ALGO_DSA ) { - mdlen = md_digest_length (hash_algo); - if (mdlen != 20) { - log_error (_("DSA requires the use of a 160 bit hash algorithm\n")); - return NULL; + int algo = hash_algo? hash_algo : gcry_md_get_algo (md); + gcry_mpi_t frame; + + if (pubkey_algo == GCRY_PK_DSA) + { + size_t n = gcry_md_get_algo_dlen(hash_algo); + if (n != 20) + { + log_error (_("DSA requires the use of a 160 bit hash algorithm\n")); + return NULL; } - - frame = md_is_secure(md)? mpi_alloc_secure((md_digest_length(hash_algo) - +BYTES_PER_MPI_LIMB-1) / BYTES_PER_MPI_LIMB ) - : mpi_alloc((md_digest_length(hash_algo) - +BYTES_PER_MPI_LIMB-1) / BYTES_PER_MPI_LIMB ); - mpi_set_buffer( frame, md_read(md, hash_algo), - md_digest_length(hash_algo), 0 ); + if (gcry_mpi_scan( &frame, GCRYMPI_FMT_USG, + gcry_md_read (md, hash_algo), &n ) ) + BUG(); } - else { - asn = md_asn_oid( algo, &asnlen, &mdlen ); - frame = do_encode_md( md, algo, mdlen, nbits, asn, asnlen, v3compathack); + else + { + byte *asn; + size_t asnlen; + + if( gcry_md_algo_info( algo, GCRYCTL_GET_ASNOID, NULL, &asnlen ) ) + log_fatal("can't get OID of algo %d: %s\n", + algo, gcry_strerror(-1)); + asn = xmalloc (asnlen); + if( gcry_md_algo_info( algo, GCRYCTL_GET_ASNOID, asn, &asnlen ) ) + BUG(); + frame = do_encode_md( md, algo, gcry_md_get_algo_dlen( algo ), + nbits, asn, asnlen, v3compathack ); + xfree (asn); } - return frame; + return frame; } |