1 /* 2 * This file and its contents are supplied under the terms of the 3 * Common Development and Distribution License ("CDDL"), version 1.0. 4 * You may only use this file in accordance with the terms of version 5 * 1.0 of the CDDL. 6 * 7 * A full copy of the text of the CDDL should have accompanied this 8 * source. A copy of the CDDL is also available via the Internet at 9 * http://www.illumos.org/license/CDDL. 10 */ 11 12 /* 13 * Copyright 2017 Nexenta Systems, Inc. All rights reserved. 14 */ 15 16 /* 17 * Dispatch function for SMB2_SESSION_SETUP 18 * 19 * Note that the Capabilities supplied in this request are an inferior 20 * subset of those given to us previously in the SMB2 Negotiate request. 21 * We need to remember the full set of capabilities from SMB2 Negotiate, 22 * and therefore ignore the subset of capabilities supplied here. 23 */ 24 25 #include <smbsrv/smb2_kproto.h> 26 27 static void smb2_ss_adjust_credits(smb_request_t *); 28 29 smb_sdrc_t 30 smb2_session_setup(smb_request_t *sr) 31 { 32 smb_arg_sessionsetup_t *sinfo; 33 uint16_t StructureSize; 34 uint8_t Flags; 35 uint8_t SecurityMode; 36 uint32_t Capabilities; /* ignored - see above */ 37 uint32_t Channel; 38 uint16_t SecBufOffset; 39 uint16_t SecBufLength; 40 uint64_t PrevSsnId; 41 uint16_t SessionFlags; 42 uint32_t status; 43 int skip; 44 int rc = 0; 45 46 sinfo = smb_srm_zalloc(sr, sizeof (smb_arg_sessionsetup_t)); 47 sr->sr_ssetup = sinfo; 48 49 rc = smb_mbc_decodef( 50 &sr->smb_data, "wbbllwwq", 51 &StructureSize, /* w */ 52 &Flags, /* b */ 53 &SecurityMode, /* b */ 54 &Capabilities, /* l */ 55 &Channel, /* l */ 56 &SecBufOffset, /* w */ 57 &SecBufLength, /* w */ 58 &PrevSsnId); /* q */ 59 if (rc) 60 return (SDRC_ERROR); 61 62 /* 63 * SMB3 multi-channel features are not supported. 64 * Once they are, this will check the dialect and 65 * whether multi-channel was negotiated, i.e. 66 * if (sr->session->dialect < SMB_VERS_3_0 || 67 * s->IsMultiChannelCapable == False) 68 * return (error...) 69 */ 70 if (Flags & SMB2_SESSION_FLAG_BINDING) { 71 status = NT_STATUS_REQUEST_NOT_ACCEPTED; 72 goto errout; 73 } 74 75 /* 76 * We're normally positioned at the security buffer now, 77 * but there could be some padding before it. 78 */ 79 skip = (SecBufOffset + sr->smb2_cmd_hdr) - 80 sr->smb_data.chain_offset; 81 if (skip < 0) 82 return (SDRC_ERROR); 83 if (skip > 0) 84 (void) smb_mbc_decodef(&sr->smb_data, "#.", skip); 85 86 /* 87 * Get the security buffer 88 */ 89 sinfo->ssi_iseclen = SecBufLength; 90 sinfo->ssi_isecblob = smb_srm_zalloc(sr, sinfo->ssi_iseclen); 91 rc = smb_mbc_decodef(&sr->smb_data, "#c", 92 sinfo->ssi_iseclen, sinfo->ssi_isecblob); 93 if (rc) 94 return (SDRC_ERROR); 95 96 /* 97 * Decoded everything. Dtrace probe, 98 * then no more early returns. 99 */ 100 DTRACE_SMB2_START(op__SessionSetup, smb_request_t *, sr); 101 102 /* 103 * The real auth. work happens in here. 104 */ 105 status = smb_authenticate_ext(sr); 106 107 SecBufOffset = SMB2_HDR_SIZE + 8; 108 SecBufLength = sinfo->ssi_oseclen; 109 SessionFlags = 0; 110 111 switch (status) { 112 113 case NT_STATUS_SUCCESS: /* Authenticated */ 114 if (sr->uid_user->u_flags & SMB_USER_FLAG_GUEST) 115 SessionFlags |= SMB2_SESSION_FLAG_IS_GUEST; 116 if (sr->uid_user->u_flags & SMB_USER_FLAG_ANON) 117 SessionFlags |= SMB2_SESSION_FLAG_IS_NULL; 118 smb2_ss_adjust_credits(sr); 119 120 /* 121 * PrevSsnId is a session that the client is reporting as 122 * having gone away, and for which we might not yet have seen 123 * a disconnect. We need to log off the previous session so 124 * any durable handles in that session will become orphans 125 * that can be reclaimed in this new session. Note that 126 * either zero or the _current_ session ID means there is 127 * no previous session to logoff. 128 */ 129 if (PrevSsnId != 0 && 130 PrevSsnId != sr->smb2_ssnid) 131 smb_server_logoff_ssnid(sr, PrevSsnId); 132 break; 133 134 /* 135 * This is not really an error, but tells the client 136 * it should send another session setup request. 137 * Not smb2_put_error because we send a payload. 138 */ 139 case NT_STATUS_MORE_PROCESSING_REQUIRED: 140 sr->smb2_status = status; 141 break; 142 143 default: 144 errout: 145 SecBufLength = 0; 146 sr->smb2_status = status; 147 break; 148 } 149 150 /* sr->smb2_status set above */ 151 DTRACE_SMB2_DONE(op__SessionSetup, smb_request_t *, sr); 152 153 /* 154 * SMB2 Session Setup reply 155 */ 156 157 rc = smb_mbc_encodef( 158 &sr->reply, 159 "wwww#c", 160 9, /* StructSize */ /* w */ 161 SessionFlags, /* w */ 162 SecBufOffset, /* w */ 163 SecBufLength, /* w */ 164 SecBufLength, /* # */ 165 sinfo->ssi_osecblob); /* c */ 166 if (rc) 167 sr->smb2_status = NT_STATUS_INTERNAL_ERROR; 168 169 return (SDRC_SUCCESS); 170 } 171 172 /* 173 * After a successful authentication, raise s_max_credits up to the 174 * normal maximum that clients are allowed to request. Also, if we 175 * haven't yet given them their initial credits, do that now. 176 * 177 * Normally, clients will request some credits with session setup, 178 * but in case they don't request enough to raise s_cur_credits 179 * up to the configured initial_credits, increase the requested 180 * credits of this SR sufficiently to make that happen. The actual 181 * increase happens in the dispatch code after we return. 182 */ 183 static void 184 smb2_ss_adjust_credits(smb_request_t *sr) 185 { 186 smb_session_t *s = sr->session; 187 188 mutex_enter(&s->s_credits_mutex); 189 s->s_max_credits = s->s_cfg.skc_maximum_credits; 190 191 if (s->s_cur_credits < s->s_cfg.skc_initial_credits) { 192 uint16_t grant; 193 194 /* How many credits we want to grant with this SR. */ 195 grant = s->s_cfg.skc_initial_credits - s->s_cur_credits; 196 197 /* 198 * Do we need to increase the smb2_credit_request? 199 * One might prefer to read this expression as: 200 * ((credit_request - credit_charge) < grant) 201 * but we know credit_charge == 1 and would rather not 202 * deal with a possibly negative value on the left, 203 * so adding credit_charge to both sides... 204 */ 205 if (sr->smb2_credit_request < (grant + 1)) { 206 sr->smb2_credit_request = (grant + 1); 207 } 208 } 209 210 mutex_exit(&s->s_credits_mutex); 211 } 212