Rewrite algorithm type parsers and make them globally available

There is some code strewn around between futility and the vb21-specific
part of hostlib to allow parsing of textual algorithm names to vboot
enums, but it is somewhat disorganized and not written in a super
efficient way. This patch rewrites it and centralizes all the algorithm
mapping stuff under 2crypto.c so it can be a single source of truth for
all of vboot. (String parsing routines still need to stay in hostlib
since not all firmware targets support things like stroul() and
strcasecmp().)

BRANCH=None
BUG=None
TEST=make runtests

Signed-off-by: Julius Werner <jwerner@chromium.org>
Change-Id: I719b2499992a6e4395a29231bc8b9a7680c5b174
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/2099447
Reviewed-by: Joel Kitching <kitching@chromium.org>
Commit-Queue: Joel Kitching <kitching@chromium.org>

4 files changed, 17 insertions, 40 deletions

diff --git a/futility/cmd_create.c b/futility/cmd_create.c
index 2f7a8d5f..aca1d4c0 100644
--- a/futility/cmd_create.c
+++ b/futility/cmd_create.c
@@ -23,6 +23,7 @@
 #include "openssl_compat.h"
 #include "util_misc.h"
 #include "vb2_common.h"
+#include "vboot_host.h"
 
 /* Command line options */
 enum {
@@ -55,7 +56,7 @@ static const struct option long_opts[] = {
 
 static void print_help(int argc, char *argv[])
 {
-	const struct vb2_text_vs_enum *entry;
+	enum vb2_hash_algorithm alg;
 
 	printf("\n"
 "Usage:  " MYNAME " %s [options] <INFILE> [<BASENAME>]\n", argv[0]);
@@ -67,10 +68,13 @@ static void print_help(int argc, char *argv[])
 "  --version <number>          Key version (default %d)\n"
 "  --hash_alg <number>         Hashing algorithm to use:\n",
 		DEFAULT_VERSION);
-	for (entry = vb2_text_vs_hash; entry->name; entry++)
-		printf("                                %d / %s%s\n",
-		       entry->num, entry->name,
-		       entry->num == VB2_HASH_SHA256 ? " (default)" : "");
+	for (alg = 0; alg < VB2_HASH_ALG_COUNT; alg++) {
+		const char *name = vb2_get_hash_algorithm_name(alg);
+		if (strcmp(name, VB2_INVALID_ALG_NAME) != 0)
+			printf("                                %d / %s%s\n",
+			       alg, name,
+			       alg == VB2_HASH_SHA256 ? " (default)" : "");
+	}
 	printf(
 "  --id <id>                   Identifier for this keypair (vb21 only)\n"
 "  --desc <text>               Human-readable description (vb21 only)\n"
diff --git a/futility/cmd_sign.c b/futility/cmd_sign.c
index 980e6d12..c95b8c97 100644
--- a/futility/cmd_sign.c
+++ b/futility/cmd_sign.c
@@ -423,7 +423,7 @@ static void print_help_kern_preamble(int argc, char *argv[])
 
 static void print_help_usbpd1(int argc, char *argv[])
 {
-	const struct vb2_text_vs_enum *entry;
+	enum vb2_hash_algorithm algo;
 
 	printf("\n"
 	       "Usage:  " MYNAME " %s --type %s [options] INFILE [OUTFILE]\n"
@@ -450,10 +450,13 @@ static void print_help_usbpd1(int argc, char *argv[])
 	       argv[0],
 	       futil_file_type_name(FILE_TYPE_USBPD1),
 	       futil_file_type_desc(FILE_TYPE_USBPD1));
-	for (entry = vb2_text_vs_hash; entry->name; entry++)
-		printf("                                   %d / %s%s\n",
-		       entry->num, entry->name,
-		       entry->num == VB2_HASH_SHA256 ? " (default)" : "");
+	for (algo = 0; algo < VB2_HASH_ALG_COUNT; algo++) {
+		const char *name = vb2_get_hash_algorithm_name(algo);
+		if (strcmp(name, VB2_INVALID_ALG_NAME) != 0)
+			printf("                                   %d / %s%s\n",
+			       algo, name,
+			       algo == VB2_HASH_SHA256 ? " (default)" : "");
+	}
 	printf("\n"
 	       "The size and offset assumptions can be overridden. "
 	       "All numbers are in bytes.\n"
diff --git a/futility/futility_options.h b/futility/futility_options.h
index a3bdd650..a79505c3 100644
--- a/futility/futility_options.h
+++ b/futility/futility_options.h
@@ -67,7 +67,4 @@ struct sign_option_s {
 };
 extern struct sign_option_s sign_option;
 
-/* Return true if hash_alg was identified, either by name or number */
-int vb2_lookup_hash_alg(const char *str, enum vb2_hash_algorithm *alg);
-
 #endif  /* VBOOT_REFERENCE_FUTILITY_OPTIONS_H_ */
diff --git a/futility/vb2_helper.c b/futility/vb2_helper.c
index fb0362ae..4d676a68 100644
--- a/futility/vb2_helper.c
+++ b/futility/vb2_helper.c
@@ -20,33 +20,6 @@
 #include "openssl_compat.h"
 #include "util_misc.h"
 
-int vb2_lookup_hash_alg(const char *str, enum vb2_hash_algorithm *alg)
-{
-	const struct vb2_text_vs_enum *entry;
-	uint32_t val;
-	char *e;
-
-	/* try string first */
-	entry = vb2_lookup_by_name(vb2_text_vs_hash, str);
-	if (entry) {
-		*alg = entry->num;
-		return 1;
-	}
-
-	/* fine, try number */
-	val = strtoul(str, &e, 0);
-	if (!*str || (e && *e))
-		/* that's not a number */
-		return 0;
-
-	if (!vb2_lookup_by_num(vb2_text_vs_hash, val))
-		/* That's not a valid alg */
-		return 0;
-
-	*alg = val;
-	return 1;
-}
-
 enum futil_file_type ft_recognize_vb21_key(uint8_t *buf, uint32_t len)
 {
 	struct vb2_public_key pubkey;