X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/1608bfe3a87311bd46e76bedfcf27daaf90b95d9..0d694692c59504838ec2043ddfe670b3a9247faf:/sshdes.c diff --git a/sshdes.c b/sshdes.c index aae172f4..1be340c4 100644 --- a/sshdes.c +++ b/sshdes.c @@ -1,6 +1,7 @@ #include #include "ssh.h" + /* des.c - implementation of DES */ @@ -655,6 +656,30 @@ static void des_3cbc_encrypt(unsigned char *dest, const unsigned char *src, des_cbc_encrypt(dest, src, len, &scheds[2]); } +static void des_cbc3_encrypt(unsigned char *dest, const unsigned char *src, + unsigned int len, DESContext *scheds) { + word32 out[2], iv0, iv1; + unsigned int i; + + assert((len & 7) == 0); + + iv0 = scheds->eiv0; + iv1 = scheds->eiv1; + for (i = 0; i < len; i += 8) { + iv0 ^= GET_32BIT_MSB_FIRST(src); src += 4; + iv1 ^= GET_32BIT_MSB_FIRST(src); src += 4; + des_encipher(out, iv0, iv1, &scheds[0]); + des_decipher(out, out[0], out[1], &scheds[1]); + des_encipher(out, out[0], out[1], &scheds[2]); + iv0 = out[0]; + iv1 = out[1]; + PUT_32BIT_MSB_FIRST(dest, iv0); dest += 4; + PUT_32BIT_MSB_FIRST(dest, iv1); dest += 4; + } + scheds->eiv0 = iv0; + scheds->eiv1 = iv1; +} + static void des_3cbc_decrypt(unsigned char *dest, const unsigned char *src, unsigned int len, DESContext *scheds) { des_cbc_decrypt(dest, src, len, &scheds[2]); @@ -662,48 +687,147 @@ static void des_3cbc_decrypt(unsigned char *dest, const unsigned char *src, des_cbc_decrypt(dest, src, len, &scheds[0]); } -DESContext keys[3]; +static void des_cbc3_decrypt(unsigned char *dest, const unsigned char *src, + unsigned int len, DESContext *scheds) { + word32 out[2], iv0, iv1, xL, xR; + unsigned int i; + + assert((len & 7) == 0); -static void des3_sesskey(unsigned char *key) { + iv0 = scheds->div0; + iv1 = scheds->div1; + for (i = 0; i < len; i += 8) { + xL = GET_32BIT_MSB_FIRST(src); src += 4; + xR = GET_32BIT_MSB_FIRST(src); src += 4; + des_decipher(out, xL, xR, &scheds[2]); + des_encipher(out, out[0], out[1], &scheds[1]); + des_decipher(out, out[0], out[1], &scheds[0]); + iv0 ^= out[0]; + iv1 ^= out[1]; + PUT_32BIT_MSB_FIRST(dest, iv0); dest += 4; + PUT_32BIT_MSB_FIRST(dest, iv1); dest += 4; + iv0 = xL; + iv1 = xR; + } + scheds->div0 = iv0; + scheds->div1 = iv1; +} + +static DESContext cskeys[3], sckeys[3]; + +static void des3_cskey(unsigned char *key) { + des_key_setup(GET_32BIT_MSB_FIRST(key), + GET_32BIT_MSB_FIRST(key+4), &cskeys[0]); + des_key_setup(GET_32BIT_MSB_FIRST(key+8), + GET_32BIT_MSB_FIRST(key+12), &cskeys[1]); + des_key_setup(GET_32BIT_MSB_FIRST(key+16), + GET_32BIT_MSB_FIRST(key+20), &cskeys[2]); + logevent("Initialised triple-DES client->server encryption"); +} + +static void des3_csiv(unsigned char *key) { + cskeys[0].eiv0 = GET_32BIT_MSB_FIRST(key); + cskeys[0].eiv1 = GET_32BIT_MSB_FIRST(key+4); +} + +static void des3_sciv(unsigned char *key) { + sckeys[0].div0 = GET_32BIT_MSB_FIRST(key); + sckeys[0].div1 = GET_32BIT_MSB_FIRST(key+4); +} + +static void des3_sckey(unsigned char *key) { des_key_setup(GET_32BIT_MSB_FIRST(key), - GET_32BIT_MSB_FIRST(key+4), &keys[0]); + GET_32BIT_MSB_FIRST(key+4), &sckeys[0]); des_key_setup(GET_32BIT_MSB_FIRST(key+8), - GET_32BIT_MSB_FIRST(key+12), &keys[1]); + GET_32BIT_MSB_FIRST(key+12), &sckeys[1]); des_key_setup(GET_32BIT_MSB_FIRST(key+16), - GET_32BIT_MSB_FIRST(key+20), &keys[2]); - logevent("Initialised triple-DES encryption"); + GET_32BIT_MSB_FIRST(key+20), &sckeys[2]); + logevent("Initialised triple-DES server->client encryption"); +} + +static void des3_sesskey(unsigned char *key) { + des3_cskey(key); + des3_sckey(key); } static void des3_encrypt_blk(unsigned char *blk, int len) { - des_3cbc_encrypt(blk, blk, len, keys); + des_3cbc_encrypt(blk, blk, len, cskeys); } static void des3_decrypt_blk(unsigned char *blk, int len) { - des_3cbc_decrypt(blk, blk, len, keys); + des_3cbc_decrypt(blk, blk, len, sckeys); } +static void des3_ssh2_encrypt_blk(unsigned char *blk, int len) { + des_cbc3_encrypt(blk, blk, len, cskeys); +} + +static void des3_ssh2_decrypt_blk(unsigned char *blk, int len) { + des_cbc3_decrypt(blk, blk, len, sckeys); +} + +void des3_decrypt_pubkey(unsigned char *key, + unsigned char *blk, int len) { + DESContext ourkeys[3]; + des_key_setup(GET_32BIT_MSB_FIRST(key), + GET_32BIT_MSB_FIRST(key+4), &ourkeys[0]); + des_key_setup(GET_32BIT_MSB_FIRST(key+8), + GET_32BIT_MSB_FIRST(key+12), &ourkeys[1]); + des_key_setup(GET_32BIT_MSB_FIRST(key), + GET_32BIT_MSB_FIRST(key+4), &ourkeys[2]); + des_3cbc_decrypt(blk, blk, len, ourkeys); +} + +void des3_encrypt_pubkey(unsigned char *key, + unsigned char *blk, int len) { + DESContext ourkeys[3]; + des_key_setup(GET_32BIT_MSB_FIRST(key), + GET_32BIT_MSB_FIRST(key+4), &ourkeys[0]); + des_key_setup(GET_32BIT_MSB_FIRST(key+8), + GET_32BIT_MSB_FIRST(key+12), &ourkeys[1]); + des_key_setup(GET_32BIT_MSB_FIRST(key), + GET_32BIT_MSB_FIRST(key+4), &ourkeys[2]); + des_3cbc_encrypt(blk, blk, len, ourkeys); +} + +struct ssh_cipher ssh_3des_ssh2 = { + NULL, + des3_csiv, des3_cskey, + des3_sciv, des3_sckey, + des3_ssh2_encrypt_blk, + des3_ssh2_decrypt_blk, + "3des-cbc", + 8 +}; + struct ssh_cipher ssh_3des = { des3_sesskey, + NULL, NULL, NULL, NULL, des3_encrypt_blk, - des3_decrypt_blk + des3_decrypt_blk, + "3des-cbc", + 8 }; static void des_sesskey(unsigned char *key) { des_key_setup(GET_32BIT_MSB_FIRST(key), - GET_32BIT_MSB_FIRST(key+4), &keys[0]); + GET_32BIT_MSB_FIRST(key+4), &cskeys[0]); logevent("Initialised single-DES encryption"); } static void des_encrypt_blk(unsigned char *blk, int len) { - des_cbc_encrypt(blk, blk, len, keys); + des_cbc_encrypt(blk, blk, len, cskeys); } static void des_decrypt_blk(unsigned char *blk, int len) { - des_cbc_decrypt(blk, blk, len, keys); + des_cbc_decrypt(blk, blk, len, cskeys); } struct ssh_cipher ssh_des = { des_sesskey, + NULL, NULL, NULL, NULL, /* SSH 2 bits - unused */ des_encrypt_blk, - des_decrypt_blk + des_decrypt_blk, + "des-cbc", /* should never be used - not a valid cipher in ssh2 */ + 8 };