layout: Add -i <region>[:<file>] support

Add an optional sub-parameter to the -i parameter to allow building the
image to be written from multiple files. This will also allow regions to
be read from flash and written to separate image files.

This is a rebase of a patch that was ported from chromiumos. A lot of
things have changed, but the idea is the same.

Original patch by Louis Yung-Chieh Lo <yjlou@chromium.org>:
Summary: Support -i partition:file feature for both read and write.
Commit: 9c7525f
Review URL: http://codereview.chromium.org/6611015

Ported version by Stefan Tauner <stefan.tauner@student.tuwien.ac.at>
and Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>:
Summary: [PATCH 2/6] layout: Add -i <region>[:<file>] support.
Review URL: https://mail.coreboot.org/pipermail/flashrom/2013-October/011729.html

Change-Id: Ic5465659605d8431d931053967b40290195cfd99
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Signed-off-by: Stefan Tauner <stefan.tauner@student.tuwien.ac.at>
Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Signed-off-by: Nico Huber <nico.huber@secunet.com>
Signed-off-by: Edward O'Callaghan <quasisec@google.com>
Signed-off-by: Daniel Campello <campello@chromium.org>
Co-Authored-by: Edward O'Callaghan <quasisec@google.com>
Co-Authored-by: Daniel Campello <campello@chromium.org>
Reviewed-on: https://review.coreboot.org/c/flashrom/+/23021
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Sam McNally <sammc@google.com>
Reviewed-by: Edward O'Callaghan <quasisec@chromium.org>

6 files changed, 234 insertions, 37 deletions

diff --git a/cli_classic.c b/cli_classic.c
index 3160d769..a22d642d 100644
--- a/cli_classic.c
+++ b/cli_classic.c
@@ -41,7 +41,7 @@ static void cli_classic_usage(const char *name)
 	       "\n\t-p <programmername>[:<parameters>] [-c <chipname>]\n"
 	       "\t\t(--flash-name|--flash-size|\n"
 	       "\t\t [-E|(-r|-w|-v) <file>]\n"
-	       "\t\t [(-l <layoutfile>|--ifd| --fmap|--fmap-file <file>) [-i <imagename>]...]\n"
+	       "\t\t [(-l <layoutfile>|--ifd| --fmap|--fmap-file <file>) [-i <region>[:<file>]]...]\n"
 	       "\t\t [-n] [-N] [-f])]\n"
 	       "\t[-V[V[V]]] [-o <logfile>]\n\n", name);
 
@@ -67,7 +67,8 @@ static void cli_classic_usage(const char *name)
 	       "      --fmap                        read ROM layout from fmap embedded in ROM\n"
 	       "      --fmap-file <fmapfile>        read ROM layout from fmap in <fmapfile>\n"
 	       "      --ifd                         read layout from an Intel Firmware Descriptor\n"
-	       " -i | --image <name>                only flash image <name> from flash layout\n"
+	       " -i | --image <region>[:<file>]     only read/write image <region> from layout\n"
+	       "                                    (optionally with data from <file>)\n"
 	       " -o | --output <logfile>            log output to <logfile>\n"
 	       "      --flash-contents <ref-file>   assume flash contents to be <ref-file>\n"
 	       " -L | --list-supported              print supported devices\n"
@@ -337,11 +338,8 @@ int main(int argc, char *argv[])
 			fmap = 1;
 			break;
 		case 'i':
-			tempstr = strdup(optarg);
-			if (register_include_arg(&include_args, tempstr)) {
-				free(tempstr);
+			if (register_include_arg(&include_args, optarg))
 				cli_classic_abort_usage(NULL);
-			}
 			break;
 		case OPTION_FLASH_CONTENTS:
 			if (referencefile)
diff --git a/flash.h b/flash.h
index 883b6f4b..c0e5c277 100644
--- a/flash.h
+++ b/flash.h
@@ -417,7 +417,7 @@ __attribute__((format(printf, 2, 3)));
 #define msg_cspew(...)	print(FLASHROM_MSG_SPEW, __VA_ARGS__)	/* chip debug spew  */
 
 /* layout.c */
-int register_include_arg(struct layout_include_args **args, char *name);
+int register_include_arg(struct layout_include_args **args, const char *arg);
 int read_romlayout(const char *name);
 int normalize_romentries(const struct flashctx *flash);
 void layout_cleanup(struct layout_include_args **args);
diff --git a/flashrom.8.tmpl b/flashrom.8.tmpl
index 02f60dc9..46345390 100644
--- a/flashrom.8.tmpl
+++ b/flashrom.8.tmpl
@@ -48,7 +48,8 @@ flashrom \- detect, read, write, verify and erase flash chips
           \fB\-p\fR <programmername>[:<parameters>] [\fB\-c\fR <chipname>]
             (\fB\-\-flash\-name\fR|\fB\-\-flash\-size\fR|
              [\fB\-E\fR|\fB\-r\fR <file>|\fB\-w\fR <file>|\fB\-v\fR <file>]
-             [(\fB\-l\fR <file>|\fB\-\-ifd|\fB \-\-fmap\fR|\fB\-\-fmap-file\fR <file>) [\fB\-i\fR <image>]]
+             [(\fB\-l\fR <file>|\fB\-\-ifd|\fB \-\-fmap\fR|\fB\-\-fmap-file\fR <file>)
+               [\fB\-i\fR <image>[:<file>]]]
              [\fB\-n\fR] [\fB\-N\fR] [\fB\-f\fR])]
          [\fB\-V\fR[\fBV\fR[\fBV\fR]]] [\fB-o\fR <logfile>]
 .SH DESCRIPTION
@@ -239,10 +240,45 @@ The following ROM images may be present in an IFD:
   gbe   gigabit ethernet firmware
   pd    platform specific data
 .TP
-.B "\-i, \-\-image <imagename>"
-Only flash region/image
-.B <imagename>
-from flash layout.
+.B "\-i, \-\-include <region>[:<file>]"
+Read or write only
+.B <region>
+to or from ROM.
+The
+.B "\-i"
+option may be used multiple times if the user wishes to read or write
+multiple regions using a single command.
+.sp
+The user may optionally specify a corresponding
+.B <file>
+for any region they wish to read or write. A read operation will read the
+corresponding regions from ROM and write individual files for each one. A write
+option will read file(s) and write to the corresponding region(s) in ROM.
+.sp
+For write operations, files specified using
+.B "\-i"
+take precedence over content from the argument to
+.B "\-w."
+.sp
+Examples:
+.sp
+  To read regions named
+.BR "foo " and " bar"
+in layout file
+.B <layout>
+into region-sized files
+.BR "foo.bin " and " bar.bin" ", run:
+.sp
+.B "    flashrom \-p prog \-l <layout> \-i foo:foo.bin -i bar:bar.bin -r rom.bin
+.sp
+  To write files
+.BR "foo.bin " and " bar.bin"
+into regions named
+.BR "foo " and " bar" " in layout file
+.BR <layout>
+to the ROM, run:
+.sp
+.B "    flashrom \-p prog \-l <layout> \-i foo:foo.bin -i bar:bar.bin -w rom.bin
 .TP
 .B "\-\-flash\-name"
 Prints out the detected flash chips name.
diff --git a/flashrom.c b/flashrom.c
index 056fc57e..3a733df6 100644
--- a/flashrom.c
+++ b/flashrom.c
@@ -1360,7 +1360,7 @@ int read_buf_from_file(unsigned char *buf, unsigned long size,
 		goto out;
 	}
 	if (image_stat.st_size != (intmax_t)size) {
-		msg_gerr("Error: Image size (%jd B) doesn't match the flash chip's size (%lu B)!\n",
+		msg_gerr("Error: Image size (%jd B) doesn't match the expected size (%lu B)!\n",
 			 (intmax_t)image_stat.st_size, size);
 		ret = 1;
 		goto out;
@@ -1378,6 +1378,51 @@ out:
 #endif
 }
 
+/**
+ * @brief Reads content to buffer from one or more files.
+ *
+ * Reads content to supplied buffer from files. If a filename is specified for
+ * individual regions using the partial read syntax ('-i <region>[:<filename>]')
+ * then this will read file data into the corresponding region in the
+ * supplied buffer.
+ *
+ * @param flashctx Flash context to be used.
+ * @param buf      Chip-sized buffer to write data to
+ * @return 0 on success
+ */
+static int read_buf_from_include_args(const struct flashctx *const flash,
+				      unsigned char *buf)
+{
+	const struct flashrom_layout *const layout = get_layout(flash);
+	const struct romentry *entry = NULL;
+
+	/*
+	 * Content will be read from -i args, so they must not overlap since
+	 * we need to know exactly what content to write to the ROM.
+	 */
+	if (included_regions_overlap(layout)) {
+		msg_gerr("Error: Included regions must not overlap when writing.\n");
+		return 1;
+	}
+
+	while ((entry = layout_next_included(layout, entry))) {
+		if (!entry->file)
+			continue;
+		if (read_buf_from_file(buf + entry->start,
+				       entry->end - entry->start + 1, entry->file))
+			return 1;
+	}
+	return 0;
+}
+
+/**
+ * @brief Writes passed data buffer into a file
+ *
+ * @param buf      Buffer with data to write
+ * @param size     Size of buffer
+ * @param filename File path to write to
+ * @return 0 on success
+ */
 int write_buf_to_file(const unsigned char *buf, unsigned long size, const char *filename)
 {
 #ifdef __LIBPAYLOAD__
@@ -1430,6 +1475,35 @@ out:
 #endif
 }
 
+/**
+ * @brief Writes content from buffer to one or more files.
+ *
+ * Writes content from supplied buffer to files. If a filename is specified for
+ * individual regions using the partial read syntax ('-i <region>[:<filename>]')
+ * then this will write files using data from the corresponding region in the
+ * supplied buffer.
+ *
+ * @param flashctx Flash context to be used.
+ * @param buf      Chip-sized buffer to read data from
+ * @return 0 on success
+ */
+static int write_buf_to_include_args(const struct flashctx *const flash,
+				     unsigned char *buf)
+{
+	const struct flashrom_layout *const layout = get_layout(flash);
+	const struct romentry *entry = NULL;
+
+	while ((entry = layout_next_included(layout, entry))) {
+		if (!entry->file)
+			continue;
+		if (write_buf_to_file(buf + entry->start,
+				      entry->end - entry->start + 1, entry->file))
+			return 1;
+	}
+
+	return 0;
+}
+
 static int read_by_layout(struct flashctx *, uint8_t *);
 int read_flash_to_file(struct flashctx *flash, const char *filename)
 {
@@ -1453,6 +1527,10 @@ int read_flash_to_file(struct flashctx *flash, const char *filename)
 		ret = 1;
 		goto out_free;
 	}
+	if (write_buf_to_include_args(flash, buf)) {
+		ret = 1;
+		goto out_free;
+	}
 
 	ret = write_buf_to_file(buf, size, filename);
 out_free:
@@ -2643,8 +2721,15 @@ int do_write(struct flashctx *const flash, const char *const filename, const cha
 		goto _free_ret;
 	}
 
+	/* Read '-w' argument first... */
 	if (read_buf_from_file(newcontents, flash_size, filename))
 		goto _free_ret;
+	/*
+	 * ... then update newcontents with contents from files provided to '-i'
+	 * args if needed.
+	 */
+	if (read_buf_from_include_args(flash, newcontents))
+		goto _free_ret;
 
 	if (referencefile) {
 		if (read_buf_from_file(refcontents, flash_size, referencefile))
@@ -2670,8 +2755,15 @@ int do_verify(struct flashctx *const flash, const char *const filename)
 		goto _free_ret;
 	}
 
+	/* Read '-v' argument first... */
 	if (read_buf_from_file(newcontents, flash_size, filename))
 		goto _free_ret;
+	/*
+	 * ... then update newcontents with contents from files provided to '-i'
+	 * args if needed.
+	 */
+	if (read_buf_from_include_args(flash, newcontents))
+		goto _free_ret;
 
 	ret = flashrom_image_verify(flash, newcontents, flash_size);
 
diff --git a/layout.c b/layout.c
index 272912c6..d0d2607e 100644
--- a/layout.c
+++ b/layout.c
@@ -52,7 +52,7 @@ int read_romlayout(const char *name)
 	romlayout = fopen(name, "r");
 
 	if (!romlayout) {
-		msg_gerr("ERROR: Could not open ROM layout (%s).\n",
+		msg_gerr("ERROR: Could not open layout file (%s).\n",
 			name);
 		return -1;
 	}
@@ -82,6 +82,7 @@ int read_romlayout(const char *name)
 		layout->entries[layout->num_entries].start = strtol(tstr1, (char **)NULL, 16);
 		layout->entries[layout->num_entries].end = strtol(tstr2, (char **)NULL, 16);
 		layout->entries[layout->num_entries].included = false;
+		layout->entries[layout->num_entries].file = NULL;
 		layout->entries[layout->num_entries].name = strdup(tempname);
 		if (!layout->entries[layout->num_entries].name) {
 			msg_gerr("Error adding layout entry: %s\n", strerror(errno));
@@ -105,44 +106,76 @@ _close_ret:
 #endif
 
 /* register an include argument (-i) for later processing */
-int register_include_arg(struct layout_include_args **args, char *name)
+int register_include_arg(struct layout_include_args **args, const char *arg)
 {
 	struct layout_include_args *tmp;
-	if (name == NULL) {
+	char *colon;
+	char *name;
+	char *file;
+
+	if (arg == NULL) {
 		msg_gerr("<NULL> is a bad region name.\n");
 		return 1;
 	}
 
-	tmp = *args;
-	while (tmp) {
+	/* -i <image>[:<file>] */
+	colon = strchr(arg, ':');
+	if (colon && !colon[1]) {
+		msg_gerr("Missing filename parameter in %s\n", arg);
+		return 1;
+	}
+	name = colon ? strndup(arg, colon - arg) : strdup(arg);
+	file = colon ? strdup(colon + 1) : NULL;
+
+	for (tmp = *args; tmp; tmp = tmp->next) {
 		if (!strcmp(tmp->name, name)) {
 			msg_gerr("Duplicate region name: \"%s\".\n", name);
-			return 1;
+			goto error;
 		}
-		tmp = tmp->next;
 	}
 
 	tmp = malloc(sizeof(struct layout_include_args));
 	if (tmp == NULL) {
 		msg_gerr("Could not allocate memory");
-		return 1;
+		goto error;
 	}
 
 	tmp->name = name;
+	tmp->file = file;
 	tmp->next = *args;
 	*args = tmp;
-
 	return 0;
+
+error:
+	free(name);
+	free(file);
+	return 1;
+}
+
+/* returns 0 to indicate success, 1 to indicate failure */
+static int include_region(struct flashrom_layout *const l, const char *name,
+			  const char *file)
+{
+	size_t i;
+	for (i = 0; i < l->num_entries; ++i) {
+		if (!strcmp(l->entries[i].name, name)) {
+			l->entries[i].included = true;
+			if (file)
+				l->entries[i].file = strdup(file);
+			return 0;
+		}
+	}
+	return 1;
 }
 
 /* returns -1 if an entry is not found, 0 if found. */
-static int find_romentry(struct flashrom_layout *const l, char *name)
+static int find_romentry(struct flashrom_layout *const l, char *name, char *file)
 {
 	if (l->num_entries == 0)
 		return -1;
 
 	msg_gspew("Looking for region \"%s\"... ", name);
-	if (flashrom_layout_include_region(l, name)) {
+	if (include_region(l, name, file)) {
 		msg_gspew("not found.\n");
 		return -1;
 	}
@@ -161,7 +194,7 @@ int process_include_args(struct flashrom_layout *l, const struct layout_include_
 	if (args == NULL)
 		return 0;
 
-	/* User has specified an area, but no layout file is loaded. */
+	/* User has specified an include argument, but no layout is loaded. */
 	if (l->num_entries == 0) {
 		msg_gerr("Region requested (with -i \"%s\"), "
 			 "but no layout data is available.\n",
@@ -171,7 +204,7 @@ int process_include_args(struct flashrom_layout *l, const struct layout_include_
 
 	tmp = args;
 	while (tmp) {
-		if (find_romentry(l, tmp->name) < 0) {
+		if (find_romentry(l, tmp->name, tmp->file) < 0) {
 			msg_gerr("Invalid region specified: \"%s\".\n",
 				 tmp->name);
 			return 1;
@@ -180,10 +213,14 @@ int process_include_args(struct flashrom_layout *l, const struct layout_include_
 		found++;
 	}
 
-	msg_ginfo("Using region%s:", found > 1 ? "s" : "");
+	msg_ginfo("Using region%s: ", found > 1 ? "s" : "");
 	tmp = args;
 	while (tmp) {
-		msg_ginfo(" \"%s\"%s", tmp->name, found > 1 ? "," : "");
+		msg_ginfo("\"%s\"", tmp->name);
+		if (tmp->file)
+			msg_ginfo(":\"%s\"", tmp->file);
+		if (found > 1)
+			msg_ginfo(", ");
 		found--;
 		tmp = tmp->next;
 	}
@@ -191,6 +228,39 @@ int process_include_args(struct flashrom_layout *l, const struct layout_include_
 	return 0;
 }
 
+/* returns boolean 1 if any regions overlap, 0 otherwise */
+int included_regions_overlap(const struct flashrom_layout *const l)
+{
+	size_t i;
+	int overlap_detected = 0;
+
+	for (i = 0; i < l->num_entries; i++) {
+		size_t j;
+
+		if (!l->entries[i].included)
+			continue;
+
+		for (j = i + 1; j < l->num_entries; j++) {
+			if (!l->entries[j].included)
+				continue;
+
+			if (l->entries[i].start > l->entries[j].end)
+				continue;
+
+			if (l->entries[i].end < l->entries[j].start)
+				continue;
+
+			msg_gdbg("Regions %s [0x%08x-0x%08x] and "
+				"%s [0x%08x-0x%08x] overlap\n",
+				l->entries[i].name, l->entries[i].start,
+				l->entries[i].end, l->entries[j].name,
+				l->entries[j].start, l->entries[j].end);
+			overlap_detected = 1;
+		}
+	}
+	return overlap_detected;
+}
+
 void layout_cleanup(struct layout_include_args **args)
 {
 	struct flashrom_layout *const layout = get_global_layout();
@@ -199,12 +269,15 @@ void layout_cleanup(struct layout_include_args **args)
 
 	while (*args) {
 		tmp = (*args)->next;
+		free((*args)->name);
+		free((*args)->file);
 		free(*args);
 		*args = tmp;
 	}
 
 	for (i = 0; i < layout->num_entries; i++) {
 		free(layout->entries[i].name);
+		free(layout->entries[i].file);
 		layout->entries[i].included = false;
 	}
 	layout->num_entries = 0;
@@ -287,14 +360,7 @@ const struct romentry *layout_next_included(
  */
 int flashrom_layout_include_region(struct flashrom_layout *const layout, const char *name)
 {
-	size_t i;
-	for (i = 0; i < layout->num_entries; ++i) {
-		if (!strcmp(layout->entries[i].name, name)) {
-			layout->entries[i].included = true;
-			return 0;
-		}
-	}
-	return 1;
+	return include_region(layout, name, NULL);
 }
 
 /**
@@ -309,8 +375,10 @@ void flashrom_layout_release(struct flashrom_layout *const layout)
 	if (!layout || layout == get_global_layout())
 		return;
 
-	for (i = 0; i < layout->num_entries; ++i)
+	for (i = 0; i < layout->num_entries; ++i) {
 		free(layout->entries[i].name);
+		free(layout->entries[i].file);
+	}
 	free(layout);
 }
 
diff --git a/layout.h b/layout.h
index cceedd1f..b11c4325 100644
--- a/layout.h
+++ b/layout.h
@@ -40,6 +40,7 @@ struct romentry {
 	chipoff_t end;
 	bool included;
 	char *name;
+	char *file;
 };
 
 struct flashrom_layout {
@@ -56,6 +57,7 @@ struct single_layout {
 
 struct layout_include_args {
 	char *name;
+	char *file;
 	struct layout_include_args *next;
 };
 
@@ -66,5 +68,6 @@ const struct flashrom_layout *get_layout(const struct flashrom_flashctx *const f
 int process_include_args(struct flashrom_layout *l, const struct layout_include_args *const args);
 const struct romentry *layout_next_included_region(const struct flashrom_layout *, chipoff_t);
 const struct romentry *layout_next_included(const struct flashrom_layout *, const struct romentry *);
+int included_regions_overlap(const struct flashrom_layout *const flashrom_layout);
 
 #endif /* !__LAYOUT_H__ */