^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) * llc_pdu.c - access to PDU internals
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * Copyright (c) 1997 by Procom Technology, Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * 2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * This program can be redistributed or modified under the terms of the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) * GNU General Public License as published by the Free Software Foundation.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) * This program is distributed without any warranty or implied warranty
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) * of merchantability or fitness for a particular purpose.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) * See the GNU General Public License for more details.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/netdevice.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <net/llc_pdu.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) static void llc_pdu_decode_pdu_type(struct sk_buff *skb, u8 *type);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) static u8 llc_pdu_get_pf_bit(struct llc_pdu_sn *pdu);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) void llc_pdu_set_cmd_rsp(struct sk_buff *skb, u8 pdu_type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) llc_pdu_un_hdr(skb)->ssap |= pdu_type;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) * pdu_set_pf_bit - sets poll/final bit in LLC header
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) * @skb: Frame to set bit in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) * @bit_value: poll/final bit (0 or 1).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) * This function sets poll/final bit in LLC header (based on type of PDU).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) * in I or S pdus, p/f bit is right bit of fourth byte in header. in U
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) * pdus p/f bit is fifth bit of third byte.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) void llc_pdu_set_pf_bit(struct sk_buff *skb, u8 bit_value)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) u8 pdu_type;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) struct llc_pdu_sn *pdu;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) llc_pdu_decode_pdu_type(skb, &pdu_type);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) pdu = llc_pdu_sn_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) switch (pdu_type) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) case LLC_PDU_TYPE_I:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) case LLC_PDU_TYPE_S:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) pdu->ctrl_2 = (pdu->ctrl_2 & 0xFE) | bit_value;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) case LLC_PDU_TYPE_U:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) pdu->ctrl_1 |= (pdu->ctrl_1 & 0xEF) | (bit_value << 4);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) * llc_pdu_decode_pf_bit - extracs poll/final bit from LLC header
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) * @skb: input skb that p/f bit must be extracted from it
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) * @pf_bit: poll/final bit (0 or 1)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) * This function extracts poll/final bit from LLC header (based on type of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) * PDU). In I or S pdus, p/f bit is right bit of fourth byte in header. In
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) * U pdus p/f bit is fifth bit of third byte.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) void llc_pdu_decode_pf_bit(struct sk_buff *skb, u8 *pf_bit)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) u8 pdu_type;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) struct llc_pdu_sn *pdu;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) llc_pdu_decode_pdu_type(skb, &pdu_type);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) pdu = llc_pdu_sn_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) switch (pdu_type) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) case LLC_PDU_TYPE_I:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) case LLC_PDU_TYPE_S:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) *pf_bit = pdu->ctrl_2 & LLC_S_PF_BIT_MASK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) case LLC_PDU_TYPE_U:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) *pf_bit = (pdu->ctrl_1 & LLC_U_PF_BIT_MASK) >> 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) * llc_pdu_init_as_disc_cmd - Builds DISC PDU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) * @skb: Address of the skb to build
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) * @p_bit: The P bit to set in the PDU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) * Builds a pdu frame as a DISC command.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) void llc_pdu_init_as_disc_cmd(struct sk_buff *skb, u8 p_bit)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) pdu->ctrl_1 = LLC_PDU_TYPE_U;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) pdu->ctrl_1 |= LLC_2_PDU_CMD_DISC;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) pdu->ctrl_1 |= ((p_bit & 1) << 4) & LLC_U_PF_BIT_MASK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) * llc_pdu_init_as_i_cmd - builds I pdu
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) * @skb: Address of the skb to build
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) * @p_bit: The P bit to set in the PDU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) * @ns: The sequence number of the data PDU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) * @nr: The seq. number of the expected I PDU from the remote
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) * Builds a pdu frame as an I command.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) void llc_pdu_init_as_i_cmd(struct sk_buff *skb, u8 p_bit, u8 ns, u8 nr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) pdu->ctrl_1 = LLC_PDU_TYPE_I;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) pdu->ctrl_2 = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) pdu->ctrl_2 |= (p_bit & LLC_I_PF_BIT_MASK); /* p/f bit */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) pdu->ctrl_1 |= (ns << 1) & 0xFE; /* set N(S) in bits 2..8 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) pdu->ctrl_2 |= (nr << 1) & 0xFE; /* set N(R) in bits 10..16 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) * llc_pdu_init_as_rej_cmd - builds REJ PDU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) * @skb: Address of the skb to build
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) * @p_bit: The P bit to set in the PDU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) * @nr: The seq. number of the expected I PDU from the remote
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) * Builds a pdu frame as a REJ command.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) void llc_pdu_init_as_rej_cmd(struct sk_buff *skb, u8 p_bit, u8 nr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) pdu->ctrl_1 = LLC_PDU_TYPE_S;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) pdu->ctrl_1 |= LLC_2_PDU_CMD_REJ;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) pdu->ctrl_2 = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) pdu->ctrl_2 |= p_bit & LLC_S_PF_BIT_MASK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) pdu->ctrl_1 &= 0x0F; /* setting bits 5..8 to zero(reserved) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) pdu->ctrl_2 |= (nr << 1) & 0xFE; /* set N(R) in bits 10..16 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) * llc_pdu_init_as_rnr_cmd - builds RNR pdu
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) * @skb: Address of the skb to build
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) * @p_bit: The P bit to set in the PDU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) * @nr: The seq. number of the expected I PDU from the remote
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) * Builds a pdu frame as an RNR command.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) void llc_pdu_init_as_rnr_cmd(struct sk_buff *skb, u8 p_bit, u8 nr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) pdu->ctrl_1 = LLC_PDU_TYPE_S;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) pdu->ctrl_1 |= LLC_2_PDU_CMD_RNR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) pdu->ctrl_2 = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) pdu->ctrl_2 |= p_bit & LLC_S_PF_BIT_MASK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) pdu->ctrl_1 &= 0x0F; /* setting bits 5..8 to zero(reserved) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) pdu->ctrl_2 |= (nr << 1) & 0xFE; /* set N(R) in bits 10..16 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) * llc_pdu_init_as_rr_cmd - Builds RR pdu
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) * @skb: Address of the skb to build
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) * @p_bit: The P bit to set in the PDU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) * @nr: The seq. number of the expected I PDU from the remote
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) * Builds a pdu frame as an RR command.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) void llc_pdu_init_as_rr_cmd(struct sk_buff *skb, u8 p_bit, u8 nr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) pdu->ctrl_1 = LLC_PDU_TYPE_S;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) pdu->ctrl_1 |= LLC_2_PDU_CMD_RR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) pdu->ctrl_2 = p_bit & LLC_S_PF_BIT_MASK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) pdu->ctrl_1 &= 0x0F; /* setting bits 5..8 to zero(reserved) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) pdu->ctrl_2 |= (nr << 1) & 0xFE; /* set N(R) in bits 10..16 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) * llc_pdu_init_as_sabme_cmd - builds SABME pdu
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) * @skb: Address of the skb to build
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) * @p_bit: The P bit to set in the PDU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) * Builds a pdu frame as an SABME command.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) void llc_pdu_init_as_sabme_cmd(struct sk_buff *skb, u8 p_bit)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) pdu->ctrl_1 = LLC_PDU_TYPE_U;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) pdu->ctrl_1 |= LLC_2_PDU_CMD_SABME;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) pdu->ctrl_1 |= ((p_bit & 1) << 4) & LLC_U_PF_BIT_MASK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) * llc_pdu_init_as_dm_rsp - builds DM response pdu
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) * @skb: Address of the skb to build
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) * @f_bit: The F bit to set in the PDU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) * Builds a pdu frame as a DM response.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) void llc_pdu_init_as_dm_rsp(struct sk_buff *skb, u8 f_bit)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) pdu->ctrl_1 = LLC_PDU_TYPE_U;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) pdu->ctrl_1 |= LLC_2_PDU_RSP_DM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) pdu->ctrl_1 |= ((f_bit & 1) << 4) & LLC_U_PF_BIT_MASK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) * llc_pdu_init_as_frmr_rsp - builds FRMR response PDU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) * @skb: Address of the frame to build
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) * @prev_pdu: The rejected PDU frame
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) * @f_bit: The F bit to set in the PDU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) * @vs: tx state vari value for the data link conn at the rejecting LLC
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) * @vr: rx state var value for the data link conn at the rejecting LLC
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) * @vzyxw: completely described in the IEEE Std 802.2 document (Pg 55)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) * Builds a pdu frame as a FRMR response.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) void llc_pdu_init_as_frmr_rsp(struct sk_buff *skb, struct llc_pdu_sn *prev_pdu,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) u8 f_bit, u8 vs, u8 vr, u8 vzyxw)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) struct llc_frmr_info *frmr_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) u8 prev_pf = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) u8 *ctrl;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) pdu->ctrl_1 = LLC_PDU_TYPE_U;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) pdu->ctrl_1 |= LLC_2_PDU_RSP_FRMR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) pdu->ctrl_1 |= ((f_bit & 1) << 4) & LLC_U_PF_BIT_MASK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) frmr_info = (struct llc_frmr_info *)&pdu->ctrl_2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) ctrl = (u8 *)&prev_pdu->ctrl_1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) FRMR_INFO_SET_REJ_CNTRL(frmr_info,ctrl);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) FRMR_INFO_SET_Vs(frmr_info, vs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) FRMR_INFO_SET_Vr(frmr_info, vr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) prev_pf = llc_pdu_get_pf_bit(prev_pdu);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) FRMR_INFO_SET_C_R_BIT(frmr_info, prev_pf);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) FRMR_INFO_SET_INVALID_PDU_CTRL_IND(frmr_info, vzyxw);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) FRMR_INFO_SET_INVALID_PDU_INFO_IND(frmr_info, vzyxw);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) FRMR_INFO_SET_PDU_INFO_2LONG_IND(frmr_info, vzyxw);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) FRMR_INFO_SET_PDU_INVALID_Nr_IND(frmr_info, vzyxw);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) FRMR_INFO_SET_PDU_INVALID_Ns_IND(frmr_info, vzyxw);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) skb_put(skb, sizeof(struct llc_frmr_info));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) * llc_pdu_init_as_rr_rsp - builds RR response pdu
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) * @skb: Address of the skb to build
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) * @f_bit: The F bit to set in the PDU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) * @nr: The seq. number of the expected data PDU from the remote
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) * Builds a pdu frame as an RR response.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) void llc_pdu_init_as_rr_rsp(struct sk_buff *skb, u8 f_bit, u8 nr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) pdu->ctrl_1 = LLC_PDU_TYPE_S;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) pdu->ctrl_1 |= LLC_2_PDU_RSP_RR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) pdu->ctrl_2 = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) pdu->ctrl_2 |= f_bit & LLC_S_PF_BIT_MASK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) pdu->ctrl_1 &= 0x0F; /* setting bits 5..8 to zero(reserved) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) pdu->ctrl_2 |= (nr << 1) & 0xFE; /* set N(R) in bits 10..16 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) * llc_pdu_init_as_rej_rsp - builds REJ response pdu
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) * @skb: Address of the skb to build
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) * @f_bit: The F bit to set in the PDU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) * @nr: The seq. number of the expected data PDU from the remote
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) * Builds a pdu frame as a REJ response.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) void llc_pdu_init_as_rej_rsp(struct sk_buff *skb, u8 f_bit, u8 nr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) pdu->ctrl_1 = LLC_PDU_TYPE_S;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) pdu->ctrl_1 |= LLC_2_PDU_RSP_REJ;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) pdu->ctrl_2 = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) pdu->ctrl_2 |= f_bit & LLC_S_PF_BIT_MASK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) pdu->ctrl_1 &= 0x0F; /* setting bits 5..8 to zero(reserved) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) pdu->ctrl_2 |= (nr << 1) & 0xFE; /* set N(R) in bits 10..16 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) * llc_pdu_init_as_rnr_rsp - builds RNR response pdu
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) * @skb: Address of the frame to build
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) * @f_bit: The F bit to set in the PDU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) * @nr: The seq. number of the expected data PDU from the remote
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) * Builds a pdu frame as an RNR response.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) void llc_pdu_init_as_rnr_rsp(struct sk_buff *skb, u8 f_bit, u8 nr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) pdu->ctrl_1 = LLC_PDU_TYPE_S;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) pdu->ctrl_1 |= LLC_2_PDU_RSP_RNR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) pdu->ctrl_2 = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) pdu->ctrl_2 |= f_bit & LLC_S_PF_BIT_MASK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) pdu->ctrl_1 &= 0x0F; /* setting bits 5..8 to zero(reserved) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) pdu->ctrl_2 |= (nr << 1) & 0xFE; /* set N(R) in bits 10..16 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) * llc_pdu_init_as_ua_rsp - builds UA response pdu
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) * @skb: Address of the frame to build
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) * @f_bit: The F bit to set in the PDU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) * Builds a pdu frame as a UA response.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) void llc_pdu_init_as_ua_rsp(struct sk_buff *skb, u8 f_bit)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) pdu->ctrl_1 = LLC_PDU_TYPE_U;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) pdu->ctrl_1 |= LLC_2_PDU_RSP_UA;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) pdu->ctrl_1 |= ((f_bit & 1) << 4) & LLC_U_PF_BIT_MASK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) * llc_pdu_decode_pdu_type - designates PDU type
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) * @skb: input skb that type of it must be designated.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) * @type: type of PDU (output argument).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) * This function designates type of PDU (I, S or U).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) static void llc_pdu_decode_pdu_type(struct sk_buff *skb, u8 *type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) if (pdu->ctrl_1 & 1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) if ((pdu->ctrl_1 & LLC_PDU_TYPE_U) == LLC_PDU_TYPE_U)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) *type = LLC_PDU_TYPE_U;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) *type = LLC_PDU_TYPE_S;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) } else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) *type = LLC_PDU_TYPE_I;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) * llc_pdu_get_pf_bit - extracts p/f bit of input PDU
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) * @pdu: pointer to LLC header.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) * This function extracts p/f bit of input PDU. at first examines type of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) * PDU and then extracts p/f bit. Returns the p/f bit.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) static u8 llc_pdu_get_pf_bit(struct llc_pdu_sn *pdu)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) u8 pdu_type;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) u8 pf_bit = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) if (pdu->ctrl_1 & 1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) if ((pdu->ctrl_1 & LLC_PDU_TYPE_U) == LLC_PDU_TYPE_U)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) pdu_type = LLC_PDU_TYPE_U;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) pdu_type = LLC_PDU_TYPE_S;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) } else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) pdu_type = LLC_PDU_TYPE_I;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) switch (pdu_type) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) case LLC_PDU_TYPE_I:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) case LLC_PDU_TYPE_S:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) pf_bit = pdu->ctrl_2 & LLC_S_PF_BIT_MASK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) case LLC_PDU_TYPE_U:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) pf_bit = (pdu->ctrl_1 & LLC_U_PF_BIT_MASK) >> 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) return pf_bit;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) }
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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