Implement first draft of CRC core

CMakeLists.txt

@@ -9,6 +9,7 @@ set (CFILES
 	main.c
 	version.c
 	named_crcs.c
+	crc.c
 )
 
 set(GEN_HEADER_PATH "${CMAKE_CURRENT_BINARY_DIR}/include/generated")

crc.c

@@ -0,0 +1,161 @@
+/*
+ * This file is part of patchelfcrc .
+ * Copyright (c) 2022 Mario Hüttel.
+ *
+ * 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, version 2 only.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <patchelfcrc/crc.h>
+#include <stdlib.h>
+#include <string.h>
+
+int crc_len_from_poly(uint64_t polynomial)
+{
+	int pos = 0;
+
+	/* Extract the MSB from the polynomial */
+	for (pos = 63; pos >= 0; pos--) {
+		if (polynomial & (((uint64_t)1ULL) << pos)) {
+			/* Highest bit found */
+			break;
+		}
+	}
+
+	return pos;
+}
+
+static uint64_t shorten_polynomial(uint64_t poly)
+{
+	int i;
+
+	for (i = 31; i <= 0; i--) {
+		if (poly & (1 << i)) {
+			poly &= ~(1<<i);
+			break;
+		}
+	}
+
+	return poly;
+}
+
+static void internal_push_byte(struct crc_calc *crc, const uint8_t *data, size_t len)
+{
+	size_t i;
+	uint32_t crc_val;
+
+	crc_val = crc->crc_val;
+
+	for (i = 0; i < len; i++, data++) {
+		crc_val = ((crc_val << 8) & crc->crc_mask) ^ crc->table[((crc_val >> (crc->crc_length-8u)) & 0xff) ^ *data];
+	}
+
+	crc->crc_val = crc_val;
+}
+
+static void fill_crc_table(struct crc_calc *crc)
+{
+	uint32_t input;
+	uint32_t crc_reg;
+	uint32_t short_poly;
+	uint32_t crc_len;
+	int i;
+
+	crc_len = crc->crc_length;
+	short_poly = (uint32_t)shorten_polynomial(crc->settings.polynomial);
+
+	for (input = 0; input <= 255u; input++) {
+
+		crc_reg = ((uint8_t)input) << (crc_len - 8u);
+
+		for (i = 7; i >= 0; i--) {
+
+			if (crc_reg & (1ul << (crc_len-1))) {
+				crc_reg <<= 1;
+				crc_reg ^= short_poly;
+			} else {
+				crc_reg <<= 1;
+			}
+		}
+		crc->table[input] = crc_reg;
+	}
+}
+
+void crc_init(struct crc_calc *crc, const struct crc_settings *settings)
+{
+	uint32_t i;
+
+	if (!crc || !settings)
+		return;
+
+	memcpy(&crc->settings, settings, sizeof(struct crc_settings));
+
+	crc->table = (uint32_t *)malloc(256 * sizeof(uint32_t));
+	crc->crc_length = crc_len_from_poly(crc->settings.polynomial);
+	crc->crc_val = settings->start_value;
+
+	crc->crc_mask = 0x0UL;
+	for (i = 0; i < crc->crc_length; i++)
+		crc->crc_mask |= (1ul << i);
+
+	/* Initialize the table */
+	fill_crc_table(crc);
+}
+
+void crc_push_bytes(struct crc_calc *crc, const uint8_t *b, size_t len)
+{
+	if (!crc)
+		return;
+
+	internal_push_byte(crc, b, len);
+}
+
+void crc_push_byte(struct crc_calc *crc, uint8_t b)
+{
+	if (!crc)
+		return;
+
+	internal_push_byte(crc, &b, 1ul);
+}
+
+void crc_destroy(struct crc_calc *crc)
+{
+	if (!crc)
+		return;
+	if (crc->table)
+		free(crc->table);
+}
+
+uint32_t crc_get_value(struct crc_calc *crc)
+{
+	return crc->crc_val;
+}
+
+void crc_finish_calc(struct crc_calc *crc)
+{
+	uint32_t val;
+	uint32_t i;
+
+	if (!crc)
+		return;
+
+	crc->crc_val ^= crc->settings.xor;
+	val = crc->crc_val;
+	if (crc->settings.rev) {
+		crc->crc_val = 0x0ul;
+		for (i = 0; i < crc->crc_length; i++) {
+			if (val & (1<<(crc->crc_length - i - 1))) {
+				crc->crc_val |= (1 << i);
+			}
+		}
+	}
+}

include/patchelfcrc/crc.h

@@ -0,0 +1,54 @@
+/*
+ * This file is part of patchelfcrc .
+ * Copyright (c) 2022 Mario Hüttel.
+ *
+ * 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, version 2 only.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _CRC_H_
+#define _CRC_H_
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <stddef.h>
+
+struct crc_settings {
+    uint64_t polynomial;
+    uint32_t xor;
+    uint32_t start_value;
+    bool rev;
+};
+
+struct crc_calc {
+    struct crc_settings settings;
+    uint32_t crc_val;
+    uint32_t crc_mask;
+    uint32_t crc_length;
+    uint32_t *table;
+};
+
+int crc_len_from_poly(uint64_t polynomial);
+
+void crc_init(struct crc_calc *crc, const struct crc_settings *settings);
+
+void crc_destroy(struct crc_calc *crc);
+
+void crc_push_byte(struct crc_calc *crc, uint8_t b);
+
+void crc_push_bytes(struct crc_calc *crc, const uint8_t *b, size_t len);
+
+void crc_finish_calc(struct crc_calc *crc);
+
+uint32_t crc_get_value(struct crc_calc *crc);
+
+#endif /* _CRC_H_ */

include/patchelfcrc/named_crcs.h

@@ -1,15 +1,26 @@
+/*
+ * This file is part of patchelfcrc .
+ * Copyright (c) 2022 Mario Hüttel.
+ *
+ * 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, version 2 only.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #ifndef _NAMED_CRCS_H_
 #define _NAMED_CRCS_H_
 
 #include <stdint.h>
 #include <stdbool.h>
-
+#include <patchelfcrc/crc.h>
-struct crc_settings {
-    uint32_t polynomial;
-    uint32_t xor;
-    uint32_t start_value;
-    bool rev;
-};
 
 struct named_crc {
     const char *name;

include/patchelfcrc/version.h

@@ -1,3 +1,20 @@
+/*
+ * This file is part of patchelfcrc .
+ * Copyright (c) 2022 Mario Hüttel.
+ *
+ * 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, version 2 only.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #ifndef _VERSION_H_
 #define _VERSION_H_
 

main.c

@@ -1,3 +1,20 @@
+/*
+ * This file is part of patchelfcrc .
+ * Copyright (c) 2022 Mario Hüttel.
+ *
+ * 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, version 2 only.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #include <stdio.h>
 #include <libelf.h>
 #include <argp.h>
@@ -5,6 +22,7 @@
 #include <string.h>
 #include <stdlib.h>
 #include <patchelfcrc/named_crcs.h>
+#include <patchelfcrc/crc.h>
 #include <patchelfcrc/version.h>
 #include <linklist-lib/singly-linked-list.h>
 
@@ -51,6 +69,8 @@ struct command_line_options {
 static error_t parse_opt(int key, char *arg, struct argp_state *state)
 {
 	struct command_line_options *args = (struct command_line_options *)state->input;
+	char *endptr;
+
 	switch (key) {
 	case ARG_KEY_DRY_RUN:
 		args->dry_run = true;
@@ -67,6 +87,13 @@ static error_t parse_opt(int key, char *arg, struct argp_state *state)
 	case ARG_KEY_LIST:
 		args->list = true;
 		break;
+	case 'p':
+		/* Polyniomial */
+		args->crc.polynomial = strtoull(arg, &endptr, 0);
+		if (endptr == arg) {
+			argp_error(state, "Error parsing polynomial: %s\n", arg);
+		}
+		break;
 	case 'l':
 		args->little_endian = true;
 		break;
@@ -140,7 +167,7 @@ static void prepare_default_opts(struct command_line_options *opts)
 	opts->granularity = GRANULARITY_BYTE;
 	opts->dry_run = false;
 	opts->crc.xor = 0UL;
-	opts->crc.polynomial = 0x04C11DB7UL;
+	opts->crc.polynomial = 0x104C11DB7UL;
 	opts->crc.start_value = 0xFFFFFFFFUL;
 	opts->crc.rev = false;
 	opts->format = FORMAT_BARE;
@@ -169,6 +196,12 @@ static void print_verbose_start_info(const struct command_line_options *cmd_opts
 	predef_crc = reverse_lookup_named_crc(&cmd_opts->crc);
 	if (predef_crc) {
 		print_debug("Predefined CRC detected: %s\n", predef_crc->name);
+	} else {
+		print_debug("Generator polynomial: 0x%lx\n", cmd_opts->crc.polynomial);
+		print_debug("Start value: 0x%x\n", cmd_opts->crc.start_value);
+		print_debug("Output XOR: 0x%x\n", cmd_opts->crc.xor);
+		print_debug("Reversed: %s\n", cmd_opts->crc.rev ? "yes" : "no");
+		print_debug("CRC length: %d\n", crc_len_from_poly(cmd_opts->crc.polynomial));
 	}
 
 	if (cmd_opts->section_list) {
@@ -197,6 +230,7 @@ static void free_cmd_args(struct command_line_options *opts)
 int main(int argc, char **argv)
 {
 	bool verbose;
+	struct crc_calc crc;
 	struct command_line_options cmd_opts;
 
 	prepare_default_opts(&cmd_opts);
@@ -209,6 +243,9 @@ int main(int argc, char **argv)
 		list_predefined_crcs();
 		goto free_cmds;
 	}
+
+	/* Build the CRC */
+	crc_init(&crc, &cmd_opts.crc);
 free_cmds:
 
 	free_cmd_args(&cmd_opts);

named_crcs.c

@@ -1,3 +1,20 @@
+/*
+ * This file is part of patchelfcrc .
+ * Copyright (c) 2022 Mario Hüttel.
+ *
+ * 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, version 2 only.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #include <patchelfcrc/named_crcs.h>
 #include <stddef.h>
 #include <string.h>
@@ -14,44 +31,44 @@
 }}
 
 const struct named_crc predefined_crc_table[] = {
-	NAMED_CRC("crc-8", 0x07, false, 0x00, 0x00),
+	NAMED_CRC("crc-8", 0x107, false, 0x00, 0x00),
-	NAMED_CRC("crc-8-darc", 0x39, true, 0x00, 0x00),
+	NAMED_CRC("crc-8-darc", 0x139, true, 0x00, 0x00),
-	NAMED_CRC("crc-8-i-code", 0x1D, false, 0xFD, 0x00),
+	NAMED_CRC("crc-8-i-code", 0x11D, false, 0xFD, 0x00),
-	NAMED_CRC("crc-8-itu", 0x07, false, 0x55, 0x55),
+	NAMED_CRC("crc-8-itu", 0x107, false, 0x55, 0x55),
-	NAMED_CRC("crc-8-maxim", 0x31, true, 0x00, 0x00),
+	NAMED_CRC("crc-8-maxim", 0x131, true, 0x00, 0x00),
-	NAMED_CRC("crc-8-rohc", 0x07, true, 0xFF, 0x00),
+	NAMED_CRC("crc-8-rohc", 0x107, true, 0xFF, 0x00),
-	NAMED_CRC("crc-8-wcdma", 0x9B, true, 0x00, 0x00),
+	NAMED_CRC("crc-8-wcdma", 0x19B, true, 0x00, 0x00),
-	NAMED_CRC("crc-16", 0x8005, true, 0x0000, 0x0000),
+	NAMED_CRC("crc-16", 0x18005, true, 0x0000, 0x0000),
-	NAMED_CRC("crc-16-buypass", 0x8005, false, 0x0000, 0x0000),
+	NAMED_CRC("crc-16-buypass", 0x18005, false, 0x0000, 0x0000),
-	NAMED_CRC("crc-16-dds-110", 0x8005, false, 0x800D, 0x0000),
+	NAMED_CRC("crc-16-dds-110", 0x18005, false, 0x800D, 0x0000),
-	NAMED_CRC("crc-16-dect", 0x0589, false, 0x0001, 0x0001),
+	NAMED_CRC("crc-16-dect", 0x10589, false, 0x0001, 0x0001),
-	NAMED_CRC("crc-16-dnp", 0x3D65, true, 0xFFFF, 0xFFFF),
+	NAMED_CRC("crc-16-dnp", 0x13D65, true, 0xFFFF, 0xFFFF),
-	NAMED_CRC("crc-16-en-13757", 0x3D65, false, 0xFFFF, 0xFFFF),
+	NAMED_CRC("crc-16-en-13757", 0x13D65, false, 0xFFFF, 0xFFFF),
-	NAMED_CRC("crc-16-genibus", 0x1021, false, 0x0000, 0xFFFF),
+	NAMED_CRC("crc-16-genibus", 0x11021, false, 0x0000, 0xFFFF),
-	NAMED_CRC("crc-16-maxim", 0x8005, true, 0xFFFF, 0xFFFF),
+	NAMED_CRC("crc-16-maxim", 0x18005, true, 0xFFFF, 0xFFFF),
-	NAMED_CRC("crc-16-mcrf4xx", 0x1021, true, 0xFFFF, 0x0000),
+	NAMED_CRC("crc-16-mcrf4xx", 0x11021, true, 0xFFFF, 0x0000),
-	NAMED_CRC("crc-16-riello", 0x1021, true, 0x554D, 0x0000),
+	NAMED_CRC("crc-16-riello", 0x11021, true, 0x554D, 0x0000),
-	NAMED_CRC("crc-16-t10-dif", 0x8BB7, false, 0x0000, 0x0000),
+	NAMED_CRC("crc-16-t10-dif", 0x18BB7, false, 0x0000, 0x0000),
-	NAMED_CRC("crc-16-teledisk", 0xA097, false, 0x0000, 0x0000),
+	NAMED_CRC("crc-16-teledisk", 0x1A097, false, 0x0000, 0x0000),
-	NAMED_CRC("crc-16-usb", 0x8005, true, 0x0000, 0xFFFF),
+	NAMED_CRC("crc-16-usb", 0x18005, true, 0x0000, 0xFFFF),
-	NAMED_CRC("x-25", 0x1021, true, 0x0000, 0xFFFF),
+	NAMED_CRC("x-25", 0x11021, true, 0x0000, 0xFFFF),
-	NAMED_CRC("xmodem", 0x1021, false, 0x0000, 0x0000),
+	NAMED_CRC("xmodem", 0x11021, false, 0x0000, 0x0000),
-	NAMED_CRC("modbus", 0x8005, true, 0xFFFF, 0x0000),
+	NAMED_CRC("modbus", 0x18005, true, 0xFFFF, 0x0000),
-	NAMED_CRC("kermit", 0x1021, true, 0x0000, 0x0000),
+	NAMED_CRC("kermit", 0x11021, true, 0x0000, 0x0000),
-	NAMED_CRC("crc-ccitt-false", 0x1021, false, 0xFFFF, 0x0000),
+	NAMED_CRC("crc-ccitt-false", 0x11021, false, 0xFFFF, 0x0000),
-	NAMED_CRC("crc-aug-ccitt", 0x1021, false, 0x1D0F, 0x0000),
+	NAMED_CRC("crc-aug-ccitt", 0x11021, false, 0x1D0F, 0x0000),
-	NAMED_CRC("crc-24", 0x864CFB, false, 0xB704CE, 0x000000),
+	NAMED_CRC("crc-24", 0x1864CFB, false, 0xB704CE, 0x000000),
-	NAMED_CRC("crc-24-flexray-a", 0x5D6DCB, false, 0xFEDCBA, 0x000000),
+	NAMED_CRC("crc-24-flexray-a", 0x15D6DCB, false, 0xFEDCBA, 0x000000),
-	NAMED_CRC("crc-24-flexray-b", 0x5D6DCB, false, 0xABCDEF, 0x000000),
+	NAMED_CRC("crc-24-flexray-b", 0x15D6DCB, false, 0xABCDEF, 0x000000),
-	NAMED_CRC("crc-32", 0x04C11DB7, true, 0x00000000, 0xFFFFFFFF),
+	NAMED_CRC("crc-32", 0x104C11DB7, true, 0x00000000, 0xFFFFFFFF),
-	NAMED_CRC("crc-32-bzip2", 0x04C11DB7, false, 0x00000000, 0xFFFFFFFF),
+	NAMED_CRC("crc-32-bzip2", 0x104C11DB7, false, 0x00000000, 0xFFFFFFFF),
-	NAMED_CRC("crc-32c", 0x1EDC6F41, true, 0x00000000, 0xFFFFFFFF),
+	NAMED_CRC("crc-32c", 0x11EDC6F41, true, 0x00000000, 0xFFFFFFFF),
-	NAMED_CRC("crc-32d", 0xA833982B, true, 0x00000000, 0xFFFFFFFF),
+	NAMED_CRC("crc-32d", 0x1A833982B, true, 0x00000000, 0xFFFFFFFF),
-	NAMED_CRC("crc-32-mpeg", 0x04C11DB7, false, 0xFFFFFFFF, 0x00000000),
+	NAMED_CRC("crc-32-mpeg", 0x104C11DB7, false, 0xFFFFFFFF, 0x00000000),
-	NAMED_CRC("posix", 0x04C11DB7, false, 0xFFFFFFFF, 0xFFFFFFFF),
+	NAMED_CRC("posix", 0x104C11DB7, false, 0xFFFFFFFF, 0xFFFFFFFF),
-	NAMED_CRC("crc-32q", 0x814141AB, false, 0x00000000, 0x00000000),
+	NAMED_CRC("crc-32q", 0x1814141AB, false, 0x00000000, 0x00000000),
-	NAMED_CRC("jamcrc", 0x04C11DB7, true, 0xFFFFFFFF, 0x00000000),
+	NAMED_CRC("jamcrc", 0x104C11DB7, true, 0xFFFFFFFF, 0x00000000),
-	NAMED_CRC("xfer", 0x000000AF, false, 0x00000000, 0x00000000),
+	NAMED_CRC("xfer", 0x1000000AF, false, 0x00000000, 0x00000000),
 	/* SENTINEL */
 	{.name = NULL, .settings = {0, 0, 0, false}},
 };
@@ -100,7 +117,7 @@ void list_predefined_crcs(void)
 	ft_write_ln(table, "Name", "Polynomial", "Reversed", "Start Value", "Output XOR");
 
 	for (iter = predefined_crc_table; iter->name; iter++) {
-		ft_printf_ln(table, "%s|0x%x|%s|0x%x|0x%x",
+		ft_printf_ln(table, "%s|0x%lx|%s|0x%x|0x%x",
 			     iter->name,
 			     iter->settings.polynomial,
 			     iter->settings.rev ? "yes" : "no",

version.c

@@ -1,3 +1,20 @@
+/*
+ * This file is part of patchelfcrc .
+ * Copyright (c) 2022 Mario Hüttel.
+ *
+ * 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, version 2 only.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #include <patchelfcrc/version.h>
 #include <generated/version.h>