Introduce utils/osmo-amr-inspect program2023q1

This program allows inspecting a list of AMR PDUs in hexstring format
present in a text file.
This allows easily finding out the properties of the PDU as well as
finding potential errors on the data.
It also allows forcing decode in different formats (octet-aligned,
bandwidth-efficient) in order to detect which may be the correct one.

Related: SYS#6161
Change-Id: Iffa6cc2e5391b77e3097d4c3b8d3f5211427dbe2

5 files changed, 342 insertions, 1 deletions

diff --git a/Makefile.am b/Makefile.am
index 55a650a..0497895 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,7 +1,7 @@
 AUTOMAKE_OPTIONS = foreign dist-bzip2 1.6
 ACLOCAL_AMFLAGS = -I m4
 
-SUBDIRS = include src examples tests
+SUBDIRS = include src examples utils tests
 
 pkgconfigdir = $(libdir)/pkgconfig
 pkgconfig_DATA = libosmo-netif.pc
diff --git a/configure.ac b/configure.ac
index 5bb0b5c..06eaf6c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -91,6 +91,7 @@ AM_CONFIG_HEADER(config.h)
 
 PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore >= 1.7.0)
 PKG_CHECK_MODULES(LIBOSMOGSM, libosmogsm >= 1.7.0)
+PKG_CHECK_MODULES(LIBOSMOCODEC, libosmocodec >= 1.7.0)
 
 AC_ARG_ENABLE([lapd_examples],
 	[AS_HELP_STRING(
@@ -144,6 +145,7 @@ AC_OUTPUT(
 	include/osmocom/netif/Makefile
 	src/Makefile
 	examples/Makefile
+	utils/Makefile
 	tests/Makefile
 	Doxyfile
 	Makefile
diff --git a/contrib/libosmo-netif.spec.in b/contrib/libosmo-netif.spec.in
index eeda3e6..6dc19ee 100644
--- a/contrib/libosmo-netif.spec.in
+++ b/contrib/libosmo-netif.spec.in
@@ -26,6 +26,7 @@ BuildRequires:  lksctp-tools-devel
 BuildRequires:  pkgconfig >= 0.20
 BuildRequires:  pkgconfig(libosmocore) >= 1.7.0
 BuildRequires:  pkgconfig(libosmogsm) >= 1.7.0
+BuildRequires:  pkgconfig(libosmocodec) >= 1.7.0
 
 %description
 Network interface demuxer library for OsmoCom projects.
diff --git a/utils/Makefile.am b/utils/Makefile.am
new file mode 100644
index 0000000..5640190
--- /dev/null
+++ b/utils/Makefile.am
@@ -0,0 +1,19 @@
+AM_CPPFLAGS = -I$(top_srcdir)/include -I$(top_builddir)/include
+AM_CFLAGS = \
+        -Wall \
+        $(LIBOSMOCORE_CFLAGS) \
+        $(LIBOSMOCODEC_CFLAGS) \
+        $(LIBOSMOGSM_CFLAGS) \
+        $(TALLOC_CFLAGS) \
+        $(NULL)
+
+LDADD = \
+        $(LIBOSMOCORE_LIBS) \
+        $(LIBOSMOCODEC_LIBS) \
+        $(LIBOSMOGSM_LIBS) \
+        $(top_builddir)/src/libosmonetif.la \
+        $(NULL)
+
+noinst_PROGRAMS = osmo-amr-inspect
+
+osmo_amr_inspect_SOURCES = osmo-amr-inspect.c
diff --git a/utils/osmo-amr-inspect.c b/utils/osmo-amr-inspect.c
new file mode 100644
index 0000000..a677b56
--- /dev/null
+++ b/utils/osmo-amr-inspect.c
@@ -0,0 +1,319 @@
+/*! \file osmo-amr-inspect.c
+ * Utility program to inspect AMR payloads */
+/*
+ * (C) 2022 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * Author: Pau espin Pedrol <pespin@sysmocom.de>
+ *
+ * All Rights Reserved
+ *
+ * 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 2 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.
+ *
+ */
+
+#include <stdio.h>
+#include <getopt.h>
+#include <errno.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <strings.h>
+
+#include <osmocom/core/utils.h>
+#include <osmocom/core/logging.h>
+#include <osmocom/codec/codec.h>
+#include <osmocom/netif/amr.h>
+
+enum force_amr_input_fmt {
+	FORCE_AMR_INPUT_FMT_AUTO = 0,
+	FORCE_AMR_INPUT_FMT_OA,
+	FORCE_AMR_INPUT_FMT_BWE,
+	FORCE_AMR_INPUT_FMT_ALL,
+};
+
+static enum force_amr_input_fmt force_fmt = FORCE_AMR_INPUT_FMT_AUTO;
+static bool use_color = false;
+
+static void help(const char *progname)
+{
+	printf("Usage: %s [-h] [-i filename] [-F (auto|oa|bwe|all)] [-C]\n",
+		progname);
+}
+
+#define println_color(color, fmt, args ...) \
+	do { \
+		if (use_color) \
+			printf(color fmt OSMO_LOGCOLOR_END "\n", ## args); \
+		else \
+			printf(fmt "\n", ## args); \
+	} while (0)
+
+#define println_red(fmt, args ...) \
+	println_color(OSMO_LOGCOLOR_RED, fmt OSMO_LOGCOLOR_END, ## args)
+
+#define println_orange(fmt, args ...) \
+	println_color(OSMO_LOGCOLOR_YELLOW, fmt OSMO_LOGCOLOR_END, ## args)
+
+static void inspect_amr_oa(const uint8_t *buf, size_t buf_len)
+{
+	const struct amr_hdr *hdr = (const struct amr_hdr *)buf;
+	size_t payload_len = buf_len - sizeof(*hdr);
+	const uint8_t *payload = hdr->data;
+	size_t ft_bytes, ft_bits;
+	printf(" octet-aligned\n");
+	printf("  CMR: %u\n", hdr->cmr);
+	printf("  F: %u\n", hdr->f);
+	printf("  FT: %u (%s)\n", hdr->ft, osmo_amr_type_name(hdr->ft));
+	printf("  Q: %u\n", hdr->q);
+	printf("  Payload (%lu bytes): %s\n",
+	       buf_len - sizeof(*hdr), osmo_hexdump_nospc(payload, payload_len));
+
+	if (hdr->f)
+		println_orange("  WARN: F=%u not supported!", hdr->f);
+	if (!osmo_amr_ft_valid(hdr->cmr))
+		println_red("  ERROR: CMR=%u not valid!", hdr->cmr);
+	if (!osmo_amr_ft_valid(hdr->ft))
+		println_red("  ERROR: FT=%u not valid!", hdr->ft);
+	if (hdr->pad1 != 0)
+		println_orange("  WARN: PAD1=0x%x not zero!", hdr->pad1);
+	if (hdr->pad2 != 0)
+		println_orange("  WARN: PAD2=0x%x not zero!", hdr->pad2);
+	ft_bytes = osmo_amr_bytes(hdr->ft);
+	if (payload_len != ft_bytes) {
+		println_red("  ERROR: Wrong payload byte-length %lu != exp %lu!", payload_len, ft_bytes);
+	} else {
+		ft_bits = osmo_amr_bits(hdr->ft);
+		if (ft_bits/8 == ft_bytes) {
+			printf("  Payload has no padding (%lu bits)\n", ft_bits);
+		} else {
+			uint8_t last_byte = payload[payload_len - 1];
+			uint8_t padding = last_byte & (0xff >> (ft_bits & 3));
+			if (padding)
+				println_orange("  WARN: Payload last byte = 0x%02x has PAD=0x%02x not zero!", last_byte, padding);
+		}
+	}
+}
+
+static void inspect_amr_bwe(const uint8_t *buf, size_t buf_len)
+{
+	const struct amr_hdr_bwe *hdr = (const struct amr_hdr_bwe *)buf;
+	size_t payload_len_bits = 6 + (buf_len - sizeof(*hdr))*8;
+	size_t ft_bits;
+	int rc;
+	uint8_t buf_oa[buf_len + 1];
+	uint8_t ft = (hdr->ft_hi << 1) | hdr->ft_lo;
+
+	printf(" bandwith-efficient\n");
+	printf("  CMR: %u\n", hdr->cmr);
+	printf("  F: %u\n", hdr->f);
+	printf("  FT: %u (%s)\n", ft, osmo_amr_type_name(ft));
+	printf("  Q: %u\n", hdr->q);
+	printf("  Payload first 6 bits: 0x%02x\n", hdr->data_start);
+	printf("  Payload continuation (%lu bytes): %s\n", buf_len - sizeof(*hdr),
+	       osmo_hexdump_nospc(buf + sizeof(*hdr), buf_len - sizeof(*hdr)));
+
+	if (hdr->f)
+		println_orange("  WARN: F=%u not supported!", hdr->f);
+	if (!osmo_amr_ft_valid(hdr->cmr))
+		println_red("  ERROR: CMR=%u not valid!", hdr->cmr);
+	if (!osmo_amr_ft_valid(ft)) {
+		println_red("  ERROR: FT=%u not valid!", ft);
+		return;
+	}
+	ft_bits = osmo_amr_bits(ft);
+	if (ft_bits != payload_len_bits) {
+		println_red("  ERROR: Wrong payload bits-length %lu != exp %lu! (FT=%u)\n", payload_len_bits, ft_bits, ft);
+		return;
+	}
+
+	if (!((AMR_HDR_BWE_LEN_BITS + ft_bits) & 0x03)) {
+		printf("  Payload has no padding (%lu bits with offset 10)\n", ft_bits);
+	} else {
+		uint8_t last_byte = buf[buf_len - 1];
+		uint8_t padding = last_byte & (0xff >> ((AMR_HDR_BWE_LEN_BITS + ft_bits) & 0x03));
+		if (padding)
+			println_orange("  WARN: Payload last byte = 0x%02x has PAD=0x%02x not zero!", last_byte, padding);
+	}
+
+	memcpy(buf_oa, buf, buf_len);
+	rc = osmo_amr_bwe_to_oa(buf_oa, buf_len, sizeof(buf_oa));
+	if (rc < 0) {
+		println_red("  ERROR: Unable to convert to octet-aligned!");
+		return;
+	}
+	printf("  Payload (octet-aligned %d bytes): %s", rc,
+	       osmo_hexdump_nospc(buf_oa + sizeof(struct amr_hdr), rc));
+}
+
+static void inspect_amr(unsigned int i, const uint8_t *buf, size_t buf_len)
+{
+	bool is_oa;
+	printf("[%u] Buffer (%lu bytes): %s\n", i, buf_len, osmo_hexdump_nospc(buf, buf_len));
+	is_oa = osmo_amr_is_oa(buf, buf_len);
+	switch (force_fmt) {
+	case FORCE_AMR_INPUT_FMT_AUTO:
+		if (is_oa)
+			inspect_amr_oa(buf, buf_len);
+		else
+			inspect_amr_bwe(buf, buf_len);
+		break;
+	case FORCE_AMR_INPUT_FMT_OA:
+		if (!is_oa)
+			println_orange(" WARN: detected as 'bwe' but forced as 'oa'");
+		inspect_amr_oa(buf, buf_len);
+		break;
+	case FORCE_AMR_INPUT_FMT_BWE:
+		if (is_oa)
+			println_orange(" WARN: detected as 'oa' but forced as 'bwe'");
+		inspect_amr_bwe(buf, buf_len);
+		break;
+	case FORCE_AMR_INPUT_FMT_ALL:
+		if (!is_oa)
+			println_orange(" WARN: detected as 'bwe' but forced as 'oa'");
+		inspect_amr_oa(buf, buf_len);
+		if (is_oa)
+			println_orange(" WARN: detected as 'oa' but forced as 'bwe'");
+		inspect_amr_bwe(buf, buf_len);
+		break;
+	default:
+		OSMO_ASSERT(0);
+	}
+	printf("\n");
+}
+
+static int read_file(const char *filename)
+{
+	FILE *fp;
+	char *line = NULL;
+	size_t len = 0;
+	ssize_t read;
+	uint8_t buf[4096];
+	int rc = 0;
+	unsigned int i = 0;
+
+	fp = fopen(filename, "r");
+	if (fp == NULL) {
+		fprintf(stderr, "Failed opening %s: %s\n", filename, strerror(errno));
+		return -errno;
+	}
+
+	while ((read = getline(&line, &len, fp)) != -1) {
+		if (len & 1) {
+			fprintf(stderr, "Failed parsing (wrong even length): %s\n", line);
+			rc = -1;
+			goto free_ret;
+		}
+		if (len > sizeof(buf)*2) {
+			fprintf(stderr, "Failed parsing (too big): %s\n", line);
+			rc = -1;
+			goto free_ret;
+		}
+		rc = osmo_hexparse(line, buf, sizeof(buf));
+		if (rc < 0) {
+			fprintf(stderr, "Failed parsing (hexparse error): %s\n", line);
+			rc = -1;
+			goto free_ret;
+		}
+		if (rc < 2) {
+			fprintf(stderr, "Too short to be an AMR buffer (%u bytes): %s\n", rc, line);
+			rc = -1;
+			goto free_ret;
+		}
+		inspect_amr(i, buf, rc);
+		i++;
+	}
+
+free_ret:
+	fclose(fp);
+	if (line)
+		free(line);
+	return rc;
+}
+
+static int read_stdin(void)
+{
+	ssize_t rc;
+	char hex_buf[4096];
+	uint8_t buf[2048];
+	rc = read(0, hex_buf, sizeof(hex_buf));
+	if (rc < 0) {
+		fprintf(stderr, "Failed reading stdin: %s\n", strerror(errno));
+		return -EIO;
+	}
+	if (rc == sizeof(hex_buf)) {
+		fprintf(stderr, "Failed parsing (input too long)\n");
+		return -ENOMEM;
+	}
+	rc = osmo_hexparse(hex_buf, buf, rc);
+	if (rc < 0) {
+		fprintf(stderr, "Failed parsing (hexparse error): %s\n", hex_buf);
+		return -1;
+	}
+	if (rc < 2) {
+		fprintf(stderr, "Too short to be an AMR buffer (%ld bytes): %s\n", rc, buf);
+		return -1;
+	}
+	inspect_amr(0, buf, rc);
+	return 0;
+}
+
+int main(int argc, char **argv)
+{
+	int opt;
+	char *filename = NULL;
+	int rc;
+
+	while ((opt = getopt(argc, argv, "i:F:Ch")) != -1) {
+		switch (opt) {
+		case 'i':
+			filename = optarg;
+			break;
+		case 'F':
+			if (strcasecmp(optarg, "auto") == 0) {
+				force_fmt = FORCE_AMR_INPUT_FMT_AUTO;
+			} else if (strcasecmp(optarg, "oa") == 0) {
+				force_fmt = FORCE_AMR_INPUT_FMT_OA;
+			} else if (strcasecmp(optarg, "bwe") == 0) {
+				force_fmt = FORCE_AMR_INPUT_FMT_BWE;
+			} else if (strcasecmp(optarg, "all") == 0) {
+				force_fmt = FORCE_AMR_INPUT_FMT_ALL;
+			} else {
+				help(argv[0]);
+				exit(1);
+			}
+			break;
+		case 'h':
+			help(argv[0]);
+			exit(0);
+			break;
+		case 'C':
+			use_color = true;
+			break;
+		default:
+			break;
+		}
+	}
+
+	if (argc > optind) {
+		fprintf(stderr, "Unsupported positional arguments in command line\n");
+		exit(2);
+	}
+
+	if (filename) {
+		rc = read_file(filename);
+		exit(-rc);
+	} else {
+		rc = read_stdin();
+		exit(-rc);
+	}
+
+	exit(0);
+}