#include "rsh_locl.h"
RCSID("$Id$");
#if defined(KRB5)
#ifdef KRB5
int key_usage = 1026;
void *ivec_in[2];
void *ivec_out[2];
void
init_ivecs(int client, int have_errsock)
{
size_t blocksize;
krb5_crypto_getblocksize(context, crypto, &blocksize);
ivec_in[0] = malloc(blocksize);
memset(ivec_in[0], client, blocksize);
if(have_errsock) {
ivec_in[1] = malloc(blocksize);
memset(ivec_in[1], 2 | client, blocksize);
} else
ivec_in[1] = ivec_in[0];
ivec_out[0] = malloc(blocksize);
memset(ivec_out[0], !client, blocksize);
if(have_errsock) {
ivec_out[1] = malloc(blocksize);
memset(ivec_out[1], 2 | !client, blocksize);
} else
ivec_out[1] = ivec_out[0];
}
#endif
ssize_t
do_read (int fd, void *buf, size_t sz, void *ivec)
{
if (do_encrypt) {
#ifdef KRB5
if(auth_method == AUTH_KRB5) {
krb5_error_code ret;
uint32_t len, outer_len;
int status;
krb5_data data;
void *edata;
ret = krb5_net_read (context, &fd, &len, 4);
if (ret <= 0)
return ret;
len = ntohl(len);
if (len > sz)
abort ();
if(ivec != NULL)
outer_len = krb5_get_wrapped_length (context, crypto, len + 4);
else
outer_len = krb5_get_wrapped_length (context, crypto, len);
edata = malloc (outer_len);
if (edata == NULL)
errx (1, "malloc: cannot allocate %u bytes", outer_len);
ret = krb5_net_read (context, &fd, edata, outer_len);
if (ret <= 0) {
free(edata);
return ret;
}
status = krb5_decrypt_ivec(context, crypto, key_usage,
edata, outer_len, &data, ivec);
free (edata);
if (status)
krb5_err (context, 1, status, "decrypting data");
if(ivec != NULL) {
unsigned long l;
if(data.length < len + 4)
errx (1, "data received is too short");
_krb5_get_int(data.data, &l, 4);
if(l != len)
errx (1, "inconsistency in received data");
memcpy (buf, (unsigned char *)data.data+4, len);
} else
memcpy (buf, data.data, len);
krb5_data_free (&data);
return len;
} else
#endif
abort ();
} else
return read (fd, buf, sz);
}
ssize_t
do_write (int fd, void *buf, size_t sz, void *ivec)
{
if (do_encrypt) {
#ifdef KRB5
if(auth_method == AUTH_KRB5) {
krb5_error_code status;
krb5_data data;
unsigned char len[4];
int ret;
_krb5_put_int(len, sz, 4);
if(ivec != NULL) {
unsigned char *tmp = malloc(sz + 4);
if(tmp == NULL)
err(1, "malloc");
_krb5_put_int(tmp, sz, 4);
memcpy(tmp + 4, buf, sz);
status = krb5_encrypt_ivec(context, crypto, key_usage,
tmp, sz + 4, &data, ivec);
free(tmp);
} else
status = krb5_encrypt_ivec(context, crypto, key_usage,
buf, sz, &data, ivec);
if (status)
krb5_err(context, 1, status, "encrypting data");
ret = krb5_net_write (context, &fd, len, 4);
if (ret != 4)
return ret;
ret = krb5_net_write (context, &fd, data.data, data.length);
if (ret != data.length)
return ret;
free (data.data);
return sz;
} else
#endif
abort();
} else
return write (fd, buf, sz);
}
#endif