/* Unix SMB/CIFS implementation. ads sasl wrapping code Copyright (C) Stefan Metzmacher 2007 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include "includes.h" #include "ads.h" #ifdef HAVE_LDAP_SASL_WRAPPING static int ads_saslwrap_setup(Sockbuf_IO_Desc *sbiod, void *arg) { ADS_STRUCT *ads = (ADS_STRUCT *)arg; ads->ldap.sbiod = sbiod; sbiod->sbiod_pvt = ads; return 0; } static int ads_saslwrap_remove(Sockbuf_IO_Desc *sbiod) { return 0; } static ber_slen_t ads_saslwrap_prepare_inbuf(ADS_STRUCT *ads) { ads->ldap.in.ofs = 0; ads->ldap.in.needed = 0; ads->ldap.in.left = 0; ads->ldap.in.size = 4 + ads->ldap.in.min_wrapped; ads->ldap.in.buf = talloc_array(ads->ldap.mem_ctx, uint8, ads->ldap.in.size); if (!ads->ldap.in.buf) { return -1; } return 0; } static ber_slen_t ads_saslwrap_grow_inbuf(ADS_STRUCT *ads) { if (ads->ldap.in.size == (4 + ads->ldap.in.needed)) { return 0; } ads->ldap.in.size = 4 + ads->ldap.in.needed; ads->ldap.in.buf = talloc_realloc(ads->ldap.mem_ctx, ads->ldap.in.buf, uint8, ads->ldap.in.size); if (!ads->ldap.in.buf) { return -1; } return 0; } static void ads_saslwrap_shrink_inbuf(ADS_STRUCT *ads) { talloc_free(ads->ldap.in.buf); ads->ldap.in.buf = NULL; ads->ldap.in.size = 0; ads->ldap.in.ofs = 0; ads->ldap.in.needed = 0; ads->ldap.in.left = 0; } static ber_slen_t ads_saslwrap_read(Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len) { ADS_STRUCT *ads = (ADS_STRUCT *)sbiod->sbiod_pvt; ber_slen_t ret; /* If ofs < 4 it means we don't have read the length header yet */ if (ads->ldap.in.ofs < 4) { ret = ads_saslwrap_prepare_inbuf(ads); if (ret < 0) return ret; ret = LBER_SBIOD_READ_NEXT(sbiod, ads->ldap.in.buf + ads->ldap.in.ofs, 4 - ads->ldap.in.ofs); if (ret <= 0) return ret; ads->ldap.in.ofs += ret; if (ads->ldap.in.ofs < 4) goto eagain; ads->ldap.in.needed = RIVAL(ads->ldap.in.buf, 0); if (ads->ldap.in.needed > ads->ldap.in.max_wrapped) { errno = EINVAL; return -1; } if (ads->ldap.in.needed < ads->ldap.in.min_wrapped) { errno = EINVAL; return -1; } ret = ads_saslwrap_grow_inbuf(ads); if (ret < 0) return ret; } /* * if there's more data needed from the remote end, * we need to read more */ if (ads->ldap.in.needed > 0) { ret = LBER_SBIOD_READ_NEXT(sbiod, ads->ldap.in.buf + ads->ldap.in.ofs, ads->ldap.in.needed); if (ret <= 0) return ret; ads->ldap.in.ofs += ret; ads->ldap.in.needed -= ret; if (ads->ldap.in.needed > 0) goto eagain; } /* * if we have a complete packet and have not yet unwrapped it * we need to call the mech specific unwrap() hook */ if (ads->ldap.in.needed == 0 && ads->ldap.in.left == 0) { ADS_STATUS status; status = ads->ldap.wrap_ops->unwrap(ads); if (!ADS_ERR_OK(status)) { errno = EACCES; return -1; } } /* * if we have unwrapped data give it to the caller */ if (ads->ldap.in.left > 0) { ret = MIN(ads->ldap.in.left, len); memcpy(buf, ads->ldap.in.buf + ads->ldap.in.ofs, ret); ads->ldap.in.ofs += ret; ads->ldap.in.left -= ret; /* * if no more is left shrink the inbuf, * this will trigger reading a new SASL packet * from the remote stream in the next call */ if (ads->ldap.in.left == 0) { ads_saslwrap_shrink_inbuf(ads); } return ret; } /* * if we don't have anything for the caller yet, * tell him to ask again */ eagain: errno = EAGAIN; return -1; } static ber_slen_t ads_saslwrap_prepare_outbuf(ADS_STRUCT *ads, uint32 len) { ads->ldap.out.ofs = 0; ads->ldap.out.left = 0; ads->ldap.out.size = 4 + ads->ldap.out.sig_size + len; ads->ldap.out.buf = talloc_array(ads->ldap.mem_ctx, uint8, ads->ldap.out.size); if (!ads->ldap.out.buf) { return -1; } return 0; } static void ads_saslwrap_shrink_outbuf(ADS_STRUCT *ads) { talloc_free(ads->ldap.out.buf); ads->ldap.out.buf = NULL; ads->ldap.out.size = 0; ads->ldap.out.ofs = 0; ads->ldap.out.left = 0; } static ber_slen_t ads_saslwrap_write(Sockbuf_IO_Desc *sbiod, void *buf, ber_len_t len) { ADS_STRUCT *ads = (ADS_STRUCT *)sbiod->sbiod_pvt; ber_slen_t ret, rlen; /* if the buffer is empty, we need to wrap in incoming buffer */ if (ads->ldap.out.left == 0) { ADS_STATUS status; if (len == 0) { errno = EINVAL; return -1; } rlen = MIN(len, ads->ldap.out.max_unwrapped); ret = ads_saslwrap_prepare_outbuf(ads, rlen); if (ret < 0) return ret; status = ads->ldap.wrap_ops->wrap(ads, (uint8 *)buf, rlen); if (!ADS_ERR_OK(status)) { errno = EACCES; return -1; } RSIVAL(ads->ldap.out.buf, 0, ads->ldap.out.left - 4); } else { rlen = -1; } ret = LBER_SBIOD_WRITE_NEXT(sbiod, ads->ldap.out.buf + ads->ldap.out.ofs, ads->ldap.out.left); if (ret <= 0) return ret; ads->ldap.out.ofs += ret; ads->ldap.out.left -= ret; if (ads->ldap.out.left == 0) { ads_saslwrap_shrink_outbuf(ads); } if (rlen > 0) return rlen; errno = EAGAIN; return -1; } static int ads_saslwrap_ctrl(Sockbuf_IO_Desc *sbiod, int opt, void *arg) { ADS_STRUCT *ads = (ADS_STRUCT *)sbiod->sbiod_pvt; int ret; switch (opt) { case LBER_SB_OPT_DATA_READY: if (ads->ldap.in.left > 0) { return 1; } ret = LBER_SBIOD_CTRL_NEXT(sbiod, opt, arg); break; default: ret = LBER_SBIOD_CTRL_NEXT(sbiod, opt, arg); break; } return ret; } static int ads_saslwrap_close(Sockbuf_IO_Desc *sbiod) { return 0; } static const Sockbuf_IO ads_saslwrap_sockbuf_io = { ads_saslwrap_setup, /* sbi_setup */ ads_saslwrap_remove, /* sbi_remove */ ads_saslwrap_ctrl, /* sbi_ctrl */ ads_saslwrap_read, /* sbi_read */ ads_saslwrap_write, /* sbi_write */ ads_saslwrap_close /* sbi_close */ }; ADS_STATUS ads_setup_sasl_wrapping(ADS_STRUCT *ads, const struct ads_saslwrap_ops *ops, void *private_data) { ADS_STATUS status; Sockbuf *sb; Sockbuf_IO *io = discard_const_p(Sockbuf_IO, &ads_saslwrap_sockbuf_io); int rc; rc = ldap_get_option(ads->ldap.ld, LDAP_OPT_SOCKBUF, &sb); status = ADS_ERROR_LDAP(rc); if (!ADS_ERR_OK(status)) { return status; } /* setup the real wrapping callbacks */ rc = ber_sockbuf_add_io(sb, io, LBER_SBIOD_LEVEL_TRANSPORT, ads); status = ADS_ERROR_LDAP(rc); if (!ADS_ERR_OK(status)) { return status; } ads->ldap.wrap_ops = ops; ads->ldap.wrap_private_data = private_data; return ADS_SUCCESS; } #else ADS_STATUS ads_setup_sasl_wrapping(ADS_STRUCT *ads, const struct ads_saslwrap_ops *ops, void *private_data) { return ADS_ERROR_NT(NT_STATUS_NOT_SUPPORTED); } #endif /* HAVE_LDAP_SASL_WRAPPING */