Edit File: llc_pdu.h
#ifndef LLC_PDU_H #define LLC_PDU_H /* * Copyright (c) 1997 by Procom Technology,Inc. * 2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br> * * This program can be redistributed or modified under the terms of the * GNU General Public License as published by the Free Software Foundation. * This program is distributed without any warranty or implied warranty * of merchantability or fitness for a particular purpose. * * See the GNU General Public License for more details. */ #include <linux/if_ether.h> /* Lengths of frame formats */ #define LLC_PDU_LEN_I 4 /* header and 2 control bytes */ #define LLC_PDU_LEN_S 4 #define LLC_PDU_LEN_U 3 /* header and 1 control byte */ /* Known SAP addresses */ #define LLC_GLOBAL_SAP 0xFF #define LLC_NULL_SAP 0x00 /* not network-layer visible */ #define LLC_MGMT_INDIV 0x02 /* station LLC mgmt indiv addr */ #define LLC_MGMT_GRP 0x03 /* station LLC mgmt group addr */ #define LLC_RDE_SAP 0xA6 /* route ... */ /* SAP field bit masks */ #define LLC_ISO_RESERVED_SAP 0x02 #define LLC_SAP_GROUP_DSAP 0x01 #define LLC_SAP_RESP_SSAP 0x01 /* Group/individual DSAP indicator is DSAP field */ #define LLC_PDU_GROUP_DSAP_MASK 0x01 #define LLC_PDU_IS_GROUP_DSAP(pdu) \ ((pdu->dsap & LLC_PDU_GROUP_DSAP_MASK) ? 0 : 1) #define LLC_PDU_IS_INDIV_DSAP(pdu) \ (!(pdu->dsap & LLC_PDU_GROUP_DSAP_MASK) ? 0 : 1) /* Command/response PDU indicator in SSAP field */ #define LLC_PDU_CMD_RSP_MASK 0x01 #define LLC_PDU_CMD 0 #define LLC_PDU_RSP 1 #define LLC_PDU_IS_CMD(pdu) ((pdu->ssap & LLC_PDU_RSP) ? 0 : 1) #define LLC_PDU_IS_RSP(pdu) ((pdu->ssap & LLC_PDU_RSP) ? 1 : 0) /* Get PDU type from 2 lowest-order bits of control field first byte */ #define LLC_PDU_TYPE_I_MASK 0x01 /* 16-bit control field */ #define LLC_PDU_TYPE_S_MASK 0x03 #define LLC_PDU_TYPE_U_MASK 0x03 /* 8-bit control field */ #define LLC_PDU_TYPE_MASK 0x03 #define LLC_PDU_TYPE_I 0 /* first bit */ #define LLC_PDU_TYPE_S 1 /* first two bits */ #define LLC_PDU_TYPE_U 3 /* first two bits */ #define LLC_PDU_TYPE_IS_I(pdu) \ ((!(pdu->ctrl_1 & LLC_PDU_TYPE_I_MASK)) ? 1 : 0) #define LLC_PDU_TYPE_IS_U(pdu) \ (((pdu->ctrl_1 & LLC_PDU_TYPE_U_MASK) == LLC_PDU_TYPE_U) ? 1 : 0) #define LLC_PDU_TYPE_IS_S(pdu) \ (((pdu->ctrl_1 & LLC_PDU_TYPE_S_MASK) == LLC_PDU_TYPE_S) ? 1 : 0) /* U-format PDU control field masks */ #define LLC_U_PF_BIT_MASK 0x10 /* P/F bit mask */ #define LLC_U_PF_IS_1(pdu) ((pdu->ctrl_1 & LLC_U_PF_BIT_MASK) ? 1 : 0) #define LLC_U_PF_IS_0(pdu) ((!(pdu->ctrl_1 & LLC_U_PF_BIT_MASK)) ? 1 : 0) #define LLC_U_PDU_CMD_MASK 0xEC /* cmd/rsp mask */ #define LLC_U_PDU_CMD(pdu) (pdu->ctrl_1 & LLC_U_PDU_CMD_MASK) #define LLC_U_PDU_RSP(pdu) (pdu->ctrl_1 & LLC_U_PDU_CMD_MASK) #define LLC_1_PDU_CMD_UI 0x00 /* Type 1 cmds/rsps */ #define LLC_1_PDU_CMD_XID 0xAC #define LLC_1_PDU_CMD_TEST 0xE0 #define LLC_2_PDU_CMD_SABME 0x6C /* Type 2 cmds/rsps */ #define LLC_2_PDU_CMD_DISC 0x40 #define LLC_2_PDU_RSP_UA 0x60 #define LLC_2_PDU_RSP_DM 0x0C #define LLC_2_PDU_RSP_FRMR 0x84 /* Type 1 operations */ /* XID information field bit masks */ /* LLC format identifier (byte 1) */ #define LLC_XID_FMT_ID 0x81 /* first byte must be this */ /* LLC types/classes identifier (byte 2) */ #define LLC_XID_CLASS_ZEROS_MASK 0xE0 /* these must be zeros */ #define LLC_XID_CLASS_MASK 0x1F /* AND with byte to get below */ #define LLC_XID_NULL_CLASS_1 0x01 /* if NULL LSAP...use these */ #define LLC_XID_NULL_CLASS_2 0x03 #define LLC_XID_NULL_CLASS_3 0x05 #define LLC_XID_NULL_CLASS_4 0x07 #define LLC_XID_NNULL_TYPE_1 0x01 /* if non-NULL LSAP...use these */ #define LLC_XID_NNULL_TYPE_2 0x02 #define LLC_XID_NNULL_TYPE_3 0x04 #define LLC_XID_NNULL_TYPE_1_2 0x03 #define LLC_XID_NNULL_TYPE_1_3 0x05 #define LLC_XID_NNULL_TYPE_2_3 0x06 #define LLC_XID_NNULL_ALL 0x07 /* Sender Receive Window (byte 3) */ #define LLC_XID_RW_MASK 0xFE /* AND with value to get below */ #define LLC_XID_MIN_RW 0x02 /* lowest-order bit always zero */ /* Type 2 operations */ #define LLC_2_SEQ_NBR_MODULO ((u8) 128) /* I-PDU masks ('ctrl' is I-PDU control word) */ #define LLC_I_GET_NS(pdu) (u8)((pdu->ctrl_1 & 0xFE) >> 1) #define LLC_I_GET_NR(pdu) (u8)((pdu->ctrl_2 & 0xFE) >> 1) #define LLC_I_PF_BIT_MASK 0x01 #define LLC_I_PF_IS_0(pdu) ((!(pdu->ctrl_2 & LLC_I_PF_BIT_MASK)) ? 1 : 0) #define LLC_I_PF_IS_1(pdu) ((pdu->ctrl_2 & LLC_I_PF_BIT_MASK) ? 1 : 0) /* S-PDU supervisory commands and responses */ #define LLC_S_PDU_CMD_MASK 0x0C #define LLC_S_PDU_CMD(pdu) (pdu->ctrl_1 & LLC_S_PDU_CMD_MASK) #define LLC_S_PDU_RSP(pdu) (pdu->ctrl_1 & LLC_S_PDU_CMD_MASK) #define LLC_2_PDU_CMD_RR 0x00 /* rx ready cmd */ #define LLC_2_PDU_RSP_RR 0x00 /* rx ready rsp */ #define LLC_2_PDU_CMD_REJ 0x08 /* reject PDU cmd */ #define LLC_2_PDU_RSP_REJ 0x08 /* reject PDU rsp */ #define LLC_2_PDU_CMD_RNR 0x04 /* rx not ready cmd */ #define LLC_2_PDU_RSP_RNR 0x04 /* rx not ready rsp */ #define LLC_S_PF_BIT_MASK 0x01 #define LLC_S_PF_IS_0(pdu) ((!(pdu->ctrl_2 & LLC_S_PF_BIT_MASK)) ? 1 : 0) #define LLC_S_PF_IS_1(pdu) ((pdu->ctrl_2 & LLC_S_PF_BIT_MASK) ? 1 : 0) #define PDU_SUPV_GET_Nr(pdu) ((pdu->ctrl_2 & 0xFE) >> 1) #define PDU_GET_NEXT_Vr(sn) (++sn & ~LLC_2_SEQ_NBR_MODULO) /* FRMR information field macros */ #define FRMR_INFO_LENGTH 5 /* 5 bytes of information */ /* * info is pointer to FRMR info field structure; 'rej_ctrl' is byte pointer * (if U-PDU) or word pointer to rejected PDU control field */ #define FRMR_INFO_SET_REJ_CNTRL(info,rej_ctrl) \ info->rej_pdu_ctrl = ((*((u8 *) rej_ctrl) & \ LLC_PDU_TYPE_U) != LLC_PDU_TYPE_U ? \ (u16)*((u16 *) rej_ctrl) : \ (((u16) *((u8 *) rej_ctrl)) & 0x00FF)) /* * Info is pointer to FRMR info field structure; 'vs' is a byte containing * send state variable value in low-order 7 bits (insure the lowest-order * bit remains zero (0)) */ #define FRMR_INFO_SET_Vs(info,vs) (info->curr_ssv = (((u8) vs) << 1)) #define FRMR_INFO_SET_Vr(info,vr) (info->curr_rsv = (((u8) vr) << 1)) /* * Info is pointer to FRMR info field structure; 'cr' is a byte containing * the C/R bit value in the low-order bit */ #define FRMR_INFO_SET_C_R_BIT(info, cr) (info->curr_rsv |= (((u8) cr) & 0x01)) /* * In the remaining five macros, 'info' is pointer to FRMR info field * structure; 'ind' is a byte containing the bit value to set in the * lowest-order bit) */ #define FRMR_INFO_SET_INVALID_PDU_CTRL_IND(info, ind) \ (info->ind_bits = ((info->ind_bits & 0xFE) | (((u8) ind) & 0x01))) #define FRMR_INFO_SET_INVALID_PDU_INFO_IND(info, ind) \ (info->ind_bits = ( (info->ind_bits & 0xFD) | (((u8) ind) & 0x02))) #define FRMR_INFO_SET_PDU_INFO_2LONG_IND(info, ind) \ (info->ind_bits = ( (info->ind_bits & 0xFB) | (((u8) ind) & 0x04))) #define FRMR_INFO_SET_PDU_INVALID_Nr_IND(info, ind) \ (info->ind_bits = ( (info->ind_bits & 0xF7) | (((u8) ind) & 0x08))) #define FRMR_INFO_SET_PDU_INVALID_Ns_IND(info, ind) \ (info->ind_bits = ( (info->ind_bits & 0xEF) | (((u8) ind) & 0x10))) /* Sequence-numbered PDU format (4 bytes in length) */ struct llc_pdu_sn { u8 dsap; u8 ssap; u8 ctrl_1; u8 ctrl_2; } __packed; static inline struct llc_pdu_sn *llc_pdu_sn_hdr(struct sk_buff *skb) { return (struct llc_pdu_sn *)skb_network_header(skb); } /* Un-numbered PDU format (3 bytes in length) */ struct llc_pdu_un { u8 dsap; u8 ssap; u8 ctrl_1; } __packed; static inline struct llc_pdu_un *llc_pdu_un_hdr(struct sk_buff *skb) { return (struct llc_pdu_un *)skb_network_header(skb); } /** * llc_pdu_header_init - initializes pdu header * @skb: input skb that header must be set into it. * @type: type of PDU (U, I or S). * @ssap: source sap. * @dsap: destination sap. * @cr: command/response bit (0 or 1). * * This function sets DSAP, SSAP and command/Response bit in LLC header. */ static inline void llc_pdu_header_init(struct sk_buff *skb, u8 type, u8 ssap, u8 dsap, u8 cr) { const int hlen = type == LLC_PDU_TYPE_U ? 3 : 4; struct llc_pdu_un *pdu; skb_push(skb, hlen); skb_reset_network_header(skb); pdu = llc_pdu_un_hdr(skb); pdu->dsap = dsap; pdu->ssap = ssap; pdu->ssap |= cr; } /** * llc_pdu_decode_sa - extracs source address (MAC) of input frame * @skb: input skb that source address must be extracted from it. * @sa: pointer to source address (6 byte array). * * This function extracts source address(MAC) of input frame. */ static inline void llc_pdu_decode_sa(struct sk_buff *skb, u8 *sa) { if (skb->protocol == htons(ETH_P_802_2)) memcpy(sa, eth_hdr(skb)->h_source, ETH_ALEN); } /** * llc_pdu_decode_da - extracts dest address of input frame * @skb: input skb that destination address must be extracted from it * @sa: pointer to destination address (6 byte array). * * This function extracts destination address(MAC) of input frame. */ static inline void llc_pdu_decode_da(struct sk_buff *skb, u8 *da) { if (skb->protocol == htons(ETH_P_802_2)) memcpy(da, eth_hdr(skb)->h_dest, ETH_ALEN); } /** * llc_pdu_decode_ssap - extracts source SAP of input frame * @skb: input skb that source SAP must be extracted from it. * @ssap: source SAP (output argument). * * This function extracts source SAP of input frame. Right bit of SSAP is * command/response bit. */ static inline void llc_pdu_decode_ssap(struct sk_buff *skb, u8 *ssap) { *ssap = llc_pdu_un_hdr(skb)->ssap & 0xFE; } /** * llc_pdu_decode_dsap - extracts dest SAP of input frame * @skb: input skb that destination SAP must be extracted from it. * @dsap: destination SAP (output argument). * * This function extracts destination SAP of input frame. right bit of * DSAP designates individual/group SAP. */ static inline void llc_pdu_decode_dsap(struct sk_buff *skb, u8 *dsap) { *dsap = llc_pdu_un_hdr(skb)->dsap & 0xFE; } /** * llc_pdu_init_as_ui_cmd - sets LLC header as UI PDU * @skb: input skb that header must be set into it. * * This function sets third byte of LLC header as a UI PDU. */ static inline void llc_pdu_init_as_ui_cmd(struct sk_buff *skb) { struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb); pdu->ctrl_1 = LLC_PDU_TYPE_U; pdu->ctrl_1 |= LLC_1_PDU_CMD_UI; } /** * llc_pdu_init_as_test_cmd - sets PDU as TEST * @skb - Address of the skb to build * * Sets a PDU as TEST */ static inline void llc_pdu_init_as_test_cmd(struct sk_buff *skb) { struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb); pdu->ctrl_1 = LLC_PDU_TYPE_U; pdu->ctrl_1 |= LLC_1_PDU_CMD_TEST; pdu->ctrl_1 |= LLC_U_PF_BIT_MASK; } /** * llc_pdu_init_as_test_rsp - build TEST response PDU * @skb: Address of the skb to build * @ev_skb: The received TEST command PDU frame * * Builds a pdu frame as a TEST response. */ static inline void llc_pdu_init_as_test_rsp(struct sk_buff *skb, struct sk_buff *ev_skb) { struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb); pdu->ctrl_1 = LLC_PDU_TYPE_U; pdu->ctrl_1 |= LLC_1_PDU_CMD_TEST; pdu->ctrl_1 |= LLC_U_PF_BIT_MASK; if (ev_skb->protocol == htons(ETH_P_802_2)) { struct llc_pdu_un *ev_pdu = llc_pdu_un_hdr(ev_skb); int dsize; dsize = ntohs(eth_hdr(ev_skb)->h_proto) - 3; memcpy(((u8 *)pdu) + 3, ((u8 *)ev_pdu) + 3, dsize); skb_put(skb, dsize); } } /* LLC Type 1 XID command/response information fields format */ struct llc_xid_info { u8 fmt_id; /* always 0x81 for LLC */ u8 type; /* different if NULL/non-NULL LSAP */ u8 rw; /* sender receive window */ } __packed; /** * llc_pdu_init_as_xid_cmd - sets bytes 3, 4 & 5 of LLC header as XID * @skb: input skb that header must be set into it. * * This function sets third,fourth,fifth and sixth bytes of LLC header as * a XID PDU. */ static inline void llc_pdu_init_as_xid_cmd(struct sk_buff *skb, u8 svcs_supported, u8 rx_window) { struct llc_xid_info *xid_info; struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb); pdu->ctrl_1 = LLC_PDU_TYPE_U; pdu->ctrl_1 |= LLC_1_PDU_CMD_XID; pdu->ctrl_1 |= LLC_U_PF_BIT_MASK; xid_info = (struct llc_xid_info *)(((u8 *)&pdu->ctrl_1) + 1); xid_info->fmt_id = LLC_XID_FMT_ID; /* 0x81 */ xid_info->type = svcs_supported; xid_info->rw = rx_window << 1; /* size of receive window */ skb_put(skb, sizeof(struct llc_xid_info)); } /** * llc_pdu_init_as_xid_rsp - builds XID response PDU * @skb: Address of the skb to build * @svcs_supported: The class of the LLC (I or II) * @rx_window: The size of the receive window of the LLC * * Builds a pdu frame as an XID response. */ static inline void llc_pdu_init_as_xid_rsp(struct sk_buff *skb, u8 svcs_supported, u8 rx_window) { struct llc_xid_info *xid_info; struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb); pdu->ctrl_1 = LLC_PDU_TYPE_U; pdu->ctrl_1 |= LLC_1_PDU_CMD_XID; pdu->ctrl_1 |= LLC_U_PF_BIT_MASK; xid_info = (struct llc_xid_info *)(((u8 *)&pdu->ctrl_1) + 1); xid_info->fmt_id = LLC_XID_FMT_ID; xid_info->type = svcs_supported; xid_info->rw = rx_window << 1; skb_put(skb, sizeof(struct llc_xid_info)); } /* LLC Type 2 FRMR response information field format */ struct llc_frmr_info { u16 rej_pdu_ctrl; /* bits 1-8 if U-PDU */ u8 curr_ssv; /* current send state variable val */ u8 curr_rsv; /* current receive state variable */ u8 ind_bits; /* indicator bits set with macro */ } __packed; extern void llc_pdu_set_cmd_rsp(struct sk_buff *skb, u8 type); extern void llc_pdu_set_pf_bit(struct sk_buff *skb, u8 bit_value); extern void llc_pdu_decode_pf_bit(struct sk_buff *skb, u8 *pf_bit); extern void llc_pdu_init_as_disc_cmd(struct sk_buff *skb, u8 p_bit); extern void llc_pdu_init_as_i_cmd(struct sk_buff *skb, u8 p_bit, u8 ns, u8 nr); extern void llc_pdu_init_as_rej_cmd(struct sk_buff *skb, u8 p_bit, u8 nr); extern void llc_pdu_init_as_rnr_cmd(struct sk_buff *skb, u8 p_bit, u8 nr); extern void llc_pdu_init_as_rr_cmd(struct sk_buff *skb, u8 p_bit, u8 nr); extern void llc_pdu_init_as_sabme_cmd(struct sk_buff *skb, u8 p_bit); extern void llc_pdu_init_as_dm_rsp(struct sk_buff *skb, u8 f_bit); extern void llc_pdu_init_as_frmr_rsp(struct sk_buff *skb, struct llc_pdu_sn *prev_pdu, u8 f_bit, u8 vs, u8 vr, u8 vzyxw); extern void llc_pdu_init_as_rr_rsp(struct sk_buff *skb, u8 f_bit, u8 nr); extern void llc_pdu_init_as_rej_rsp(struct sk_buff *skb, u8 f_bit, u8 nr); extern void llc_pdu_init_as_rnr_rsp(struct sk_buff *skb, u8 f_bit, u8 nr); extern void llc_pdu_init_as_ua_rsp(struct sk_buff *skb, u8 f_bit); #endif /* LLC_PDU_H */