Implementation of Advanced Mobile Phone Service (AMPS)

1 files changed, 185 insertions, 0 deletions

diff --git a/src/amps/sysinfo.c b/src/amps/sysinfo.c
new file mode 100644
index 0000000..204de08
--- /dev/null
+++ b/src/amps/sysinfo.c
@@ -0,0 +1,185 @@
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+#include <stdlib.h>
+#include <time.h>
+#include "../common/timer.h"
+#include "amps.h"
+#include "frame.h"
+
+static struct sysinfo_reg_incr default_reg_incr = {
+	450,
+};
+
+static struct sysinfo_loc_area default_loc_area = {
+	0,
+	0,
+	0,
+	0,
+};
+
+static struct sysinfo_new_acc default_new_acc = {
+	0,
+};
+
+static struct sysinfo_overload default_overload = {
+	{ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 },
+};
+
+static struct sysinfo_acc_type default_acc_type = {
+	1,
+	0,
+	0,
+	0,
+	0,
+};
+
+static struct sysinfo_acc_attempt default_acc_attempt = {
+	10,
+	10,
+	10,
+	10,
+};
+
+void init_sysinfo(amps_si *si, int cmac, int vmac, int dcc, int sid1, int regh, int regr, int pureg, int pdreg, int locaid, int regincr)
+{
+	int i;
+
+	memset(si, 0, sizeof(*si));
+
+	/* all words */
+	si->dcc = dcc;
+	/* VC assginment */
+	si->vmac = vmac;
+
+	/* filler */
+	si->filler.cmac = cmac;
+	si->filler.sdcc1 = 0;
+	si->filler.sdcc2 = 0;
+	si->filler.wfom = 1; /* must be set to ignore B/I bit */
+
+	/* Word 1 */
+	si->word1.sid1 = sid1;
+	si->word1.ep = 1; /* shall be 0 */
+	si->word1.auth = 0;
+	si->word1.pci = 0;
+
+	/* Word 2 */
+	si->word2.s = 1;
+	si->word2.e = 1;
+	si->word2.regh = regh;
+	si->word2.regr = regr;
+	si->word2.dtx = 0;
+	si->word2.n_1 = 20;
+	si->word2.rcf = 1; /* must be set to ignore B/I bit */
+	si->word2.cpa = 1; /* must be set for combined CC+PC */
+	si->word2.cmax_1 = 20;
+
+	/* registration increment */
+	si->reg_incr.regincr = regincr;
+
+	/* location area */
+	si->loc_area.pureg = pureg;
+	si->loc_area.pdreg = pdreg;
+	if (locaid >= 0) {
+		si->loc_area.lreg = 1;
+		si->loc_area.locaid = locaid;
+	}
+
+	/* new access channel set */
+	si->new_acc.newacc = 0;
+
+	/* overload control */
+	for (i = 0; i < 16; i++)
+		si->overload.olc[i] = 1;
+
+	/* Acces Tyoe */
+	/* 'bis' must be 0, so the phone does not wait for busy bit.
+	 * We cannot respond with B/I fast enough due to processing delay.
+	 * So we don't set the B/I bit to busy on reception of message.
+	 * The access type message (including this 'bis') must also be included.
+	 */
+	si->acc_type.bis = 0; /* must be clear to ignore B/I bit */
+	si->acc_type.pci_home = 0; /* if set, bscap must allso be set */
+	si->acc_type.pci_roam = 0; /* if set, bscap must allso be set */
+	si->acc_type.bspc = 0;
+	si->acc_type.bscap = 0;
+
+	/* access attempt parameters */
+	si->acc_attempt.maxbusy_pgr = 10;
+	si->acc_attempt.maxsztr_pgr = 10;
+	si->acc_attempt.maxbusy_other = 10;
+	si->acc_attempt.maxsztr_other = 10;
+
+	/* registration ID */
+	si->reg_id.regid = 1000;
+}
+
+void prepare_sysinfo(amps_si *si)
+{
+	int i = 0;
+
+	si->type[i++] = SYSINFO_WORD1;
+	si->type[i++] = SYSINFO_WORD2;
+	si->type[i++] = SYSINFO_REG_ID;
+	/* include only messages that differ from default */
+	if (!!memcmp(&si->reg_incr, &default_reg_incr, sizeof(si->reg_incr)))
+		si->type[i++] = SYSINFO_REG_INCR;
+	if (!!memcmp(&si->loc_area, &default_loc_area, sizeof(si->loc_area)))
+		si->type[i++] = SYSINFO_LOC_AREA;
+	if (!!memcmp(&si->new_acc, &default_new_acc, sizeof(si->new_acc)))
+		si->type[i++] = SYSINFO_NEW_ACC;
+	if (!!memcmp(&si->overload, &default_overload, sizeof(si->overload)))
+		si->type[i++] = SYSINFO_OVERLOAD;
+	if (!!memcmp(&si->acc_type, &default_acc_type, sizeof(si->acc_type)))
+		si->type[i++] = SYSINFO_ACC_TYPE;
+	if (!!memcmp(&si->acc_attempt, &default_acc_attempt, sizeof(si->acc_attempt)))
+		si->type[i++] = SYSINFO_ACC_ATTEMPT;
+	si->num = i; /* train is running */
+	si->count = 0; /* first message in train */
+	if (i > sizeof(si->type) / sizeof(si->type[0])) {
+		fprintf(stderr, "si type array overflow, pleas fix!\n");
+		abort();
+	}
+}
+
+uint64_t get_sysinfo(amps_si *si)
+{
+	int count, nawc, end = 0;
+	time_t ti = time(NULL);
+
+	count = si->count;
+
+	if (++si->count == si->num) {
+		end = 1;
+		si->num = 0; /* train is over */
+	}
+
+	switch (si->type[count]) {
+	case SYSINFO_WORD1:
+		nawc = si->num - 1;
+		return amps_encode_word1_system(si->dcc, si->word1.sid1, si->word1.ep, si->word1.auth, si->word1.pci, nawc);
+	case SYSINFO_WORD2:
+		return amps_encode_word2_system(si->dcc, si->word2.s, si->word2.e, si->word2.regh, si->word2.regr, si->word2.dtx, si->word2.n_1, si->word2.rcf, si->word2.cpa, si->word2.cmax_1, end);
+	case SYSINFO_REG_ID:
+		/* use time stamp to generate regid */
+		si->reg_id.regid = ti & 0xfffff;
+		return amps_encode_registration_id(si->dcc, si->reg_id.regid, end);
+	case SYSINFO_REG_INCR:
+		return amps_encode_registration_increment(si->dcc, si->reg_incr.regincr, end);
+	case SYSINFO_LOC_AREA:
+		return amps_encode_location_area(si->dcc, si->loc_area.pureg, si->loc_area.pdreg, si->loc_area.lreg, si->loc_area.locaid, end);
+	case SYSINFO_NEW_ACC:
+		return amps_encode_new_access_channel_set(si->dcc, si->new_acc.newacc, end);
+	case SYSINFO_OVERLOAD:
+		return amps_encode_overload_control(si->dcc, si->overload.olc, end);
+	case SYSINFO_ACC_TYPE:
+		return amps_encode_access_type(si->dcc, si->acc_type.bis, si->acc_type.pci_home, si->acc_type.pci_roam, si->acc_type.bspc, si->acc_type.bscap, end);
+	case SYSINFO_ACC_ATTEMPT:
+		return amps_encode_access_attempt(si->dcc, si->acc_attempt.maxbusy_pgr, si->acc_attempt.maxsztr_pgr, si->acc_attempt.maxbusy_other, si->acc_attempt.maxsztr_other, end);
+	}
+
+	fprintf(stderr, "get_sysinfo unknown type, please fix!\n");
+	abort();
+}
+