X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/371e569c350575d3f9b41c71e2ff51de9ef62483..b50ee9a8fd3605c2fedfdcafc5901c7e8aebfbbd:/sshdes.c diff --git a/sshdes.c b/sshdes.c index d8b3369d..14ac7f68 100644 --- a/sshdes.c +++ b/sshdes.c @@ -296,7 +296,7 @@ static word32 bitsel(word32 * input, const int *bitnums, int size) return ret; } -void des_key_setup(word32 key_msw, word32 key_lsw, DESContext * sched) +static void des_key_setup(word32 key_msw, word32 key_lsw, DESContext * sched) { static const int PC1_Cbits[] = { @@ -520,7 +520,8 @@ static const word32 SPboxes[8][64] = { bitswap(R, L, 16, 0x0000FFFF), \ bitswap(R, L, 4, 0x0F0F0F0F)) -void des_encipher(word32 * output, word32 L, word32 R, DESContext * sched) +static void des_encipher(word32 * output, word32 L, word32 R, + DESContext * sched) { word32 swap, s0246, s1357; @@ -559,7 +560,8 @@ void des_encipher(word32 * output, word32 L, word32 R, DESContext * sched) output[1] = R; } -void des_decipher(word32 * output, word32 L, word32 R, DESContext * sched) +static void des_decipher(word32 * output, word32 L, word32 R, + DESContext * sched) { word32 swap, s0246, s1357; @@ -742,26 +744,55 @@ static void des_cbc3_decrypt(unsigned char *dest, const unsigned char *src, scheds->iv1 = iv1; } +static void des_sdctr3(unsigned char *dest, const unsigned char *src, + unsigned int len, DESContext * scheds) +{ + word32 b[2], iv0, iv1, tmp; + unsigned int i; + + assert((len & 7) == 0); + + iv0 = scheds->iv0; + iv1 = scheds->iv1; + for (i = 0; i < len; i += 8) { + des_encipher(b, iv0, iv1, &scheds[2]); + des_decipher(b, b[0], b[1], &scheds[1]); + des_encipher(b, b[0], b[1], &scheds[0]); + tmp = GET_32BIT_MSB_FIRST(src); + PUT_32BIT_MSB_FIRST(dest, tmp ^ b[0]); + src += 4; + dest += 4; + tmp = GET_32BIT_MSB_FIRST(src); + PUT_32BIT_MSB_FIRST(dest, tmp ^ b[0]); + src += 4; + dest += 4; + if ((iv0 = (iv0 + 1) & 0xffffffff) == 0) + iv1 = (iv1 + 1) & 0xffffffff; + } + scheds->iv0 = iv0; + scheds->iv1 = iv1; +} + static void *des3_make_context(void) { - return smalloc(3*sizeof(DESContext)); + return snewn(3, DESContext); } static void *des3_ssh1_make_context(void) { - /* Need 3 keys for each direction, in SSH1 */ - return smalloc(6*sizeof(DESContext)); + /* Need 3 keys for each direction, in SSH-1 */ + return snewn(6, DESContext); } static void *des_make_context(void) { - return smalloc(sizeof(DESContext)); + return snew(DESContext); } static void *des_ssh1_make_context(void) { - /* Need one key for each direction, in SSH1 */ - return smalloc(2*sizeof(DESContext)); + /* Need one key for each direction, in SSH-1 */ + return snewn(2, DESContext); } static void des3_free_context(void *handle) /* used for both 3DES and DES */ @@ -825,6 +856,12 @@ static void des3_ssh2_decrypt_blk(void *handle, unsigned char *blk, int len) des_cbc3_decrypt(blk, blk, len, keys); } +static void des3_ssh2_sdctr(void *handle, unsigned char *blk, int len) +{ + DESContext *keys = (DESContext *) handle; + des_sdctr3(blk, blk, len, keys); +} + static void des_ssh2_encrypt_blk(void *handle, unsigned char *blk, int len) { DESContext *keys = (DESContext *) handle; @@ -895,26 +932,87 @@ void des3_encrypt_pubkey_ossh(unsigned char *key, unsigned char *iv, memset(ourkeys, 0, sizeof(ourkeys)); } +static void des_keysetup_xdmauth(unsigned char *keydata, DESContext *dc) +{ + unsigned char key[8]; + int i, nbits, j; + unsigned int bits; + + bits = 0; + nbits = 0; + j = 0; + for (i = 0; i < 8; i++) { + if (nbits < 7) { + bits = (bits << 8) | keydata[j]; + nbits += 8; + j++; + } + key[i] = (bits >> (nbits - 7)) << 1; + bits &= ~(0x7F << (nbits - 7)); + nbits -= 7; + } + + des_key_setup(GET_32BIT_MSB_FIRST(key), GET_32BIT_MSB_FIRST(key + 4), dc); +} + +void des_encrypt_xdmauth(unsigned char *keydata, unsigned char *blk, int len) +{ + DESContext dc; + des_keysetup_xdmauth(keydata, &dc); + des_cbc_encrypt(blk, blk, 24, &dc); +} + +void des_decrypt_xdmauth(unsigned char *keydata, unsigned char *blk, int len) +{ + DESContext dc; + des_keysetup_xdmauth(keydata, &dc); + des_cbc_decrypt(blk, blk, 24, &dc); +} + static const struct ssh2_cipher ssh_3des_ssh2 = { des3_make_context, des3_free_context, des3_iv, des3_key, des3_ssh2_encrypt_blk, des3_ssh2_decrypt_blk, "3des-cbc", - 8, 168, "triple-DES" + 8, 168, "triple-DES CBC" +}; + +static const struct ssh2_cipher ssh_3des_ssh2_ctr = { + des3_make_context, des3_free_context, des3_iv, des3_key, + des3_ssh2_sdctr, des3_ssh2_sdctr, + "3des-ctr", + 8, 168, "triple-DES SDCTR" }; /* - * Single DES in ssh2. It isn't clear that "des-cbc" is an official - * cipher name, but ssh.com support it and apparently aren't the - * only people to do so, so we sigh and implement it anyway. + * Single DES in SSH-2. "des-cbc" is marked as HISTORIC in + * draft-ietf-secsh-assignednumbers-04.txt, referring to + * FIPS-46-3. ("Single DES (i.e., DES) will be permitted + * for legacy systems only.") , but ssh.com support it and + * apparently aren't the only people to do so, so we sigh + * and implement it anyway. */ static const struct ssh2_cipher ssh_des_ssh2 = { - des3_make_context, des3_free_context, des3_iv, des_key, + des_make_context, des3_free_context, des3_iv, des_key, des_ssh2_encrypt_blk, des_ssh2_decrypt_blk, "des-cbc", - 8, 56, "single-DES" + 8, 56, "single-DES CBC" }; +static const struct ssh2_cipher ssh_des_sshcom_ssh2 = { + des_make_context, des3_free_context, des3_iv, des_key, + des_ssh2_encrypt_blk, des_ssh2_decrypt_blk, + "des-cbc@ssh.com", + 8, 56, "single-DES CBC" +}; + +/* + * "3des-ctr" is disabled because it hasn't had any interoperability + * testing, which is in turn because I couldn't find another implementation + * to test against. Once it's been tested, it can be enabled in standard + * builds. + */ static const struct ssh2_cipher *const des3_list[] = { +/* &ssh_3des_ssh2_ctr, */ &ssh_3des_ssh2 }; @@ -924,18 +1022,19 @@ const struct ssh2_ciphers ssh2_3des = { }; static const struct ssh2_cipher *const des_list[] = { - &ssh_des_ssh2 + &ssh_des_ssh2, + &ssh_des_sshcom_ssh2 }; const struct ssh2_ciphers ssh2_des = { - sizeof(des3_list) / sizeof(*des_list), + sizeof(des_list) / sizeof(*des_list), des_list }; const struct ssh_cipher ssh_3des = { des3_ssh1_make_context, des3_free_context, des3_sesskey, des3_encrypt_blk, des3_decrypt_blk, - 8, "triple-DES" + 8, "triple-DES inner-CBC" }; static void des_sesskey(void *handle, unsigned char *key) @@ -960,5 +1059,5 @@ static void des_decrypt_blk(void *handle, unsigned char *blk, int len) const struct ssh_cipher ssh_des = { des_ssh1_make_context, des3_free_context, des_sesskey, des_encrypt_blk, des_decrypt_blk, - 8, "single-DES" + 8, "single-DES CBC" };