elogtool: add "add" command
Adds "add" command to elogtool. This command allows adding elog events
manually. It supports event type and, optionally, event data.
If the free buffer space is < 1/4 of the total space, it shrinks the
buffer, making sure that ~1/4 of the free space is available.
BUG=b:172210863
TEST=./elogtool add 0x17 0101
./elogtool add 0x18
Repeated the same tests on buffers that needed to be shrunk.
Change-Id: Ia6fdf4f951565f842d1bff52173811b52f617f66
Signed-off-by: Ricardo Quesada <ricardoq@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/57397
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>
diff --git a/util/cbfstool/elogtool.c b/util/cbfstool/elogtool.c
index 1b1794a..4cce5a6 100644
--- a/util/cbfstool/elogtool.c
+++ b/util/cbfstool/elogtool.c
@@ -1,5 +1,6 @@
/* SPDX-License-Identifier: BSD-3-Clause */
+#include <assert.h>
#include <getopt.h>
#include <stdbool.h>
#include <stdint.h>
@@ -14,6 +15,9 @@
#include "eventlog.h"
+/* Only refers to the data max size. The "-1" is the checksum byte */
+#define ELOG_MAX_EVENT_DATA_SIZE (ELOG_MAX_EVENT_SIZE - sizeof(struct event_header) - 1)
+
enum elogtool_return {
ELOGTOOL_EXIT_SUCCESS = 0,
ELOGTOOL_EXIT_BAD_ARGS,
@@ -26,6 +30,7 @@
static int cmd_list(const struct buffer *);
static int cmd_clear(const struct buffer *);
+static int cmd_add(const struct buffer *);
static const struct {
const char *name;
@@ -35,8 +40,12 @@
} cmds[] = {
{"list", cmd_list, false},
{"clear", cmd_clear, true},
+ {"add", cmd_add, true},
};
+static char **cmd_argv; /* Command arguments */
+static char *argv0; /* Used as invoked_as */
+
static struct option long_options[] = {
{"file", required_argument, 0, 'f'},
{"help", no_argument, 0, 'h'},
@@ -45,12 +54,13 @@
static void usage(char *invoked_as)
{
- fprintf(stderr, "elogtool: list elog events\n\n"
+ fprintf(stderr, "elogtool: edit elog events\n\n"
"USAGE:\n"
"\t%s COMMAND [-f <filename>]\n\n"
"where, COMMAND is:\n"
- " list lists all the event logs in human readable format\n"
- " clear clears all the event logs\n"
+ " list lists all the event logs in human readable format\n"
+ " clear clears all the event logs\n"
+ " add <event_type> [event_data] add an entry to the event log\n"
"\n"
"ARGS\n"
"-f, --file <filename> File that holds event log partition.\n"
@@ -115,11 +125,14 @@
return ELOGTOOL_EXIT_SUCCESS;
}
+/* Buffer offset must point to a valid event_header struct */
static size_t next_available_event_offset(const struct buffer *buf)
{
const struct event_header *event;
struct buffer copy, *iter = ©
+ assert(buffer_offset(buf) >= sizeof(struct elog_header));
+
buffer_clone(iter, buf);
while (buffer_size(iter) >= sizeof(struct event_header)) {
@@ -134,6 +147,52 @@
return buffer_offset(iter) - buffer_offset(buf);
}
+/*
+ * Shrinks buffer by ~bytes_to_shrink, then appends a LOG_CLEAR event,
+ * and finally fills the remaining area with EOL events.
+ * Buffer offset must point to a valid event_header struct.
+ */
+static int shrink_buffer(const struct buffer *buf, size_t bytes_to_shrink)
+{
+ struct buffer copy, *iter = ©
+ const struct event_header *event;
+ uint32_t cleared;
+ int remaining;
+ uint8_t *data;
+
+ assert(buffer_offset(buf) >= sizeof(struct elog_header));
+
+ buffer_clone(©, buf);
+
+ /* Save copy of first event for later */
+ data = buffer_get(buf);
+
+ /* Set buffer offset pointing to the event right after bytes_to_shrink */
+ while (buffer_offset(iter) < bytes_to_shrink) {
+ event = buffer_get(iter);
+ assert(!(event->type == ELOG_TYPE_EOL || event->length == 0));
+
+ buffer_seek(iter, event->length);
+ }
+
+ /* Must be relative to the buffer offset */
+ cleared = buffer_offset(iter) - buffer_offset(buf);
+ remaining = buffer_size(iter);
+
+ /* Overlapping copy */
+ memmove(data, data + cleared, remaining);
+ memset(data + remaining, ELOG_TYPE_EOL, cleared);
+
+ /* Re-init copy to have a clean offset. Needed for init_event() */
+ buffer_clone(©, buf);
+ buffer_seek(©, next_available_event_offset(©));
+
+ if (!eventlog_init_event(©, ELOG_TYPE_LOG_CLEAR, &cleared, sizeof(cleared)))
+ return ELOGTOOL_EXIT_NOT_ENOUGH_BUFFER_SPACE;
+
+ return ELOGTOOL_EXIT_SUCCESS;
+}
+
static int cmd_list(const struct buffer *buf)
{
const struct event_header *event;
@@ -182,6 +241,122 @@
return ELOGTOOL_EXIT_SUCCESS;
}
+static void cmd_add_usage(void)
+{
+ usage(argv0);
+
+ fprintf(stderr, "\n\nSpecific to ADD command:\n"
+ "\n"
+ "<event_type>: an hexadecimal number (0-255). Prefix '0x' is optional\n"
+ "[event_data]: (optional) a series of hexadecimal numbers. Must be:\n"
+ " - len(event_data) %% 2 == 0\n"
+ " - len(event_data) in bytes <= %ld\n"
+ "\n"
+ "Example:\n"
+ "%s add 0x16 01ABF0 # 01ABF0 is actually three bytes: 0x01, 0xAB and 0xF0\n"
+ "%s add 17 # 17 is in hexa\n",
+ ELOG_MAX_EVENT_DATA_SIZE, argv0, argv0
+ );
+}
+
+static int cmd_add_parse_args(uint8_t *type, uint8_t *data, size_t *data_size)
+{
+ char byte[3] = {0};
+ int argc = 0;
+ char *endptr;
+ long value;
+ int len;
+
+ while (cmd_argv[argc] != NULL)
+ argc++;
+
+ if (argc != 1 && argc != 2)
+ return ELOGTOOL_EXIT_BAD_ARGS;
+
+ /* Force type to be an hexa value to be consistent with the data values */
+ value = strtol(cmd_argv[0], NULL, 16);
+ if (value > 255) {
+ fprintf(stderr, "Error: Event type should be between 0-0xff; "
+ "got: 0x%04lx\n", value);
+ return ELOGTOOL_EXIT_BAD_ARGS;
+ }
+
+ *type = value;
+
+ if (argc == 1)
+ return ELOGTOOL_EXIT_SUCCESS;
+
+ /* Assuming argc == 2 */
+ len = strlen(cmd_argv[1]);
+
+ /* Needs 2 bytes per number */
+ if (len % 2 != 0) {
+ fprintf(stderr,
+ "Error: Event data length should be an even number; got: %d\n", len);
+ return ELOGTOOL_EXIT_BAD_ARGS;
+ }
+
+ *data_size = len / 2;
+
+ if (*data_size > ELOG_MAX_EVENT_DATA_SIZE) {
+ fprintf(stderr,
+ "Error: Event data length (in bytes) should be <= %ld; got: %ld\n",
+ ELOG_MAX_EVENT_DATA_SIZE, *data_size);
+ return ELOGTOOL_EXIT_BAD_ARGS;
+ }
+
+ for (unsigned int i = 0; i < *data_size; i++) {
+ byte[0] = *cmd_argv[1]++;
+ byte[1] = *cmd_argv[1]++;
+ data[i] = strtol(byte, &endptr, 16);
+ if (endptr != &byte[2]) {
+ fprintf(stderr, "Error: Event data length contains invalid data. "
+ "Only hexa digits are valid\n");
+ return ELOGTOOL_EXIT_BAD_ARGS;
+ }
+ }
+
+ return ELOGTOOL_EXIT_SUCCESS;
+}
+
+/* Appends an elog entry to EventLog buffer. */
+static int cmd_add(const struct buffer *buf)
+{
+ uint8_t data[ELOG_MAX_EVENT_DATA_SIZE];
+ size_t data_size = 0;
+ struct buffer copy;
+ uint8_t type = 0;
+ size_t next_event;
+ size_t threshold;
+ int ret;
+
+ if (cmd_add_parse_args(&type, data, &data_size) != ELOGTOOL_EXIT_SUCCESS) {
+ cmd_add_usage();
+ return ELOGTOOL_EXIT_BAD_ARGS;
+ }
+
+ buffer_clone(©, buf);
+ buffer_seek(©, sizeof(struct elog_header));
+
+ threshold = buffer_size(©) * 3 / 4;
+ next_event = next_available_event_offset(©);
+
+ if (next_event > threshold) {
+ /* Shrink ~ 1/4 of the size */
+ ret = shrink_buffer(©, buffer_size(buf) - threshold);
+ if (ret != ELOGTOOL_EXIT_SUCCESS)
+ return ret;
+ next_event = next_available_event_offset(©);
+ }
+
+ buffer_seek(©, next_event);
+
+ if (!eventlog_init_event(©, type, data, data_size))
+ return ELOGTOOL_EXIT_NOT_ENOUGH_BUFFER_SPACE;
+
+ return ELOGTOOL_EXIT_SUCCESS;
+}
+
int main(int argc, char **argv)
{
char *filename = NULL;
@@ -234,6 +409,9 @@
for (i = 0; i < ARRAY_SIZE(cmds); i++) {
if (!strcmp(cmds[i].name, argv[optind])) {
+ /* For commands that parse their own arguments. */
+ cmd_argv = &argv[optind+1];
+ argv0 = argv[0];
ret = cmds[i].func(&buf);
break;
}