Sbat code generation improves

generate_sbat_var_defs.c

@@ -9,119 +9,158 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdbool.h>
 #include <string.h>
 
 typedef struct sbat_revocation sbat_revocation;
 
 struct sbat_revocation {
-	int date;
+	unsigned int date;
 	char *revocations;
 	sbat_revocation *next;
 };
 
 static sbat_revocation *revlisthead;
 
-int
-readfile(char *SbatLevel_Variable)
+static void
+free_revocation_list(void)
+{
+	sbat_revocation *rle = revlisthead;
+	while (rle) {
+		sbat_revocation *next = rle->next;
+		free(rle->revocations);
+		free(rle);
+		rle = next;
+	}
+	revlisthead = NULL;
+}
+
+static int
+check_revocation_line(const char *line)
+{
+	int num = -1;
+	if (sscanf(line, "%*[^, \t],%*[0-9]%n", &num) < 0 ||
+	    num < 0 || line[num] != '\0') {
+		fprintf(stderr, "Invalid revocation line: %s\n", line);
+		return -1;
+	}
+	return 0;
+}
+
+static void
+chomp(char *str)
+{
+	size_t len = strlen(str);
+	if (len > 0 && str[--len] == '\n')
+		str[len] = '\0';
+}
+
+static int
+readfile(const char *SbatLevel_Variable)
 {
 	FILE *varfilep;
 	char line[1024];
-	int date;
 	int ret = -1;
 
-	unsigned int revocationsp = 0;
-
 	sbat_revocation *revlistlast = NULL;
 	sbat_revocation *revlistentry = NULL;
 
-	revlisthead = NULL;
+	free_revocation_list();
 
 	varfilep = fopen(SbatLevel_Variable, "r");
-	if (varfilep == NULL)
+	if (varfilep == NULL) {
+		fprintf(stderr, "Error opening file %s\n", SbatLevel_Variable);
 		return -1;
+	}
 
 	while (fgets(line, sizeof(line), varfilep) != NULL) {
-		if (sscanf(line, "sbat,1,%d\n", &date) && strlen(line) == 18) {
-			revlistentry = calloc(1, sizeof(sbat_revocation));
-			if (revlistentry == NULL)
+		unsigned int date;
+		size_t revocationsp = 0;
+
+		if (!sscanf(line, "sbat,1,%u\n", &date) || strlen(line) != 18)
+			continue;
+		revlistentry = calloc(1, sizeof(sbat_revocation));
+		if (revlistentry == NULL) {
+			fprintf(stderr, "Out of memory\n");
+			goto err;
+		}
+		if (revlisthead == NULL)
+			revlisthead = revlistentry;
+		else
+			revlistlast->next = revlistentry;
+
+		revlistlast = revlistentry;
+
+		revlistentry->date = date;
+		while (fgets(line, sizeof(line), varfilep) != NULL) {
+			chomp(line);
+
+			char *new = NULL;
+			new = realloc(revlistentry->revocations,
+			              revocationsp + strlen(line) + 3);
+			if (new == NULL) {
+				fprintf(stderr, "Out of memory\n");
 				goto err;
-			if (revlisthead == NULL)
-				revlisthead = revlistentry;
-			else
-				revlistlast->next = revlistentry;
-
-			revlistlast = revlistentry;
-
-			revlistentry->date = date;
-			while (line[0] != '\n' &&
-			       fgets(line, sizeof(line), varfilep) != NULL) {
-				char *new = NULL;
-				new = realloc(revlistentry->revocations,
-				              revocationsp + strlen(line) + 2);
-				if (new == NULL) {
-					ret = -1;
-					goto err;
-				}
-				revlistentry->revocations = new;
-				if (strlen(line) > 1) {
-					line[strlen(line) - 1] = 0;
-					sprintf(revlistentry->revocations +
-					                revocationsp,
-					        "%s\\n", line);
-					revocationsp =
-						revocationsp + strlen(line) + 2;
-				}
 			}
-			revocationsp = 0;
+			new[revocationsp] = '\0';
+			revlistentry->revocations = new;
+			if (strlen(line) == 0)
+				break;
+
+			if (check_revocation_line(line))
+				goto err;
+			sprintf(revlistentry->revocations + revocationsp,
+			        "%s\\n", line);
+			revocationsp = strlen(revlistentry->revocations);
 		}
 	}
 
-	ret = 1;
+	if (!ferror(varfilep))
+		ret = 0;
 err:
-	if (ret < 0 && revlisthead) {
-		sbat_revocation *rle = revlisthead;
-		while (rle) {
-			sbat_revocation *next = rle->next;
-			if (rle->revocations)
-				free(rle->revocations);
-			free(rle);
-			rle = next;
-		}
-		revlisthead = NULL;
-	}
+	if (ret < 0)
+		free_revocation_list();
 	fclose(varfilep);
 	return ret;
 }
 
-int
-writefile()
+static int
+writefile(void)
 {
-	int epochfound = 0;
-	int epochdate = 2021030218;
-	int latestdate = 0;
+	bool epochfound = false;
+	unsigned int epochdate = 2021030218;
+	unsigned int latestdate = 0;
 
-	sbat_revocation *revlistentry;
-	sbat_revocation *latest_revlistentry = NULL;
+	const sbat_revocation *revlistentry;
+	const sbat_revocation *latest_revlistentry = NULL;
 
 	revlistentry = revlisthead;
 
 	while (revlistentry != NULL) {
 		if (revlistentry->date == epochdate) {
-			printf("#ifndef GEN_SBAT_VAR_DEFS_H_\n"
+			if (epochfound) {
+				fprintf(stderr, "Only one epoch expected\n");
+				return -1;
+			}
+			printf("// Autogenerated by generate_sbat_var_defs\n\n"
+			       "#ifndef GEN_SBAT_VAR_DEFS_H_\n"
 			       "#define GEN_SBAT_VAR_DEFS_H_\n"
 			       "#ifndef ENABLE_SHIM_DEVEL\n\n"
 			       "#ifndef SBAT_AUTOMATIC_DATE\n"
 			       "#define SBAT_AUTOMATIC_DATE 2024040900\n"
-			       "#endif /* SBAT_AUTOMATIC_DATE */\n"
-			       "#if SBAT_AUTOMATIC_DATE == %d\n"
+			       "#endif /* SBAT_AUTOMATIC_DATE */\n\n"
+			       "#if SBAT_AUTOMATIC_DATE == %u\n"
 			       "#define SBAT_VAR_AUTOMATIC_REVOCATIONS\n",
 			       revlistentry->date);
-			epochfound = 1;
-		} else if (epochfound == 1) {
-			printf("#elif SBAT_AUTOMATIC_DATE == %d\n"
+			epochfound = true;
+		} else if (epochfound) {
+			printf("#elif SBAT_AUTOMATIC_DATE == %u\n"
 			       "#define SBAT_VAR_AUTOMATIC_REVOCATIONS \"%s\"\n",
 			       revlistentry->date,
 			       revlistentry->revocations);
+		} else {
+			fprintf(stderr, "Revocation not expected before epoch\n");
+			return -1;
 		}
 		if (revlistentry->date > latestdate) {
 			latest_revlistentry = revlistentry;
@@ -130,25 +169,27 @@ writefile()
 		revlistentry = revlistentry->next;
 	}
 
-	if (epochfound == 0 || !latest_revlistentry)
+	if (!epochfound || !latest_revlistentry) {
+		fprintf(stderr, "Epoch not found\n");
 		return -1;
+	}
 
 	printf("#else\n"
 	       "#error \"Unknown SBAT_AUTOMATIC_DATE\"\n"
 	       "#endif /* SBAT_AUTOMATIC_DATE == */\n\n"
 	       "#define SBAT_VAR_AUTOMATIC_DATE QUOTEVAL(SBAT_AUTOMATIC_DATE)\n"
 	       "#define SBAT_VAR_AUTOMATIC \\\n"
-               "	SBAT_VAR_SIG SBAT_VAR_VERSION SBAT_VAR_AUTOMATIC_DATE \"\\n\" \\\n"
-               "	SBAT_VAR_AUTOMATIC_REVOCATIONS\n\n");
+	       "	SBAT_VAR_SIG SBAT_VAR_VERSION SBAT_VAR_AUTOMATIC_DATE \"\\n\" \\\n"
+	       "	SBAT_VAR_AUTOMATIC_REVOCATIONS\n\n");
 
-	printf("#define SBAT_VAR_LATEST_DATE \"%d\"\n"
+	printf("#define SBAT_VAR_LATEST_DATE \"%u\"\n"
 	       "#define SBAT_VAR_LATEST_REVOCATIONS \"%s\"\n",
 	       latest_revlistentry->date,
 	       latest_revlistentry->revocations);
 
 	printf("#define SBAT_VAR_LATEST \\\n"
-               "	SBAT_VAR_SIG SBAT_VAR_VERSION SBAT_VAR_LATEST_DATE \"\\n\" \\\n"
-               "	SBAT_VAR_LATEST_REVOCATIONS\n\n"
+	       "	SBAT_VAR_SIG SBAT_VAR_VERSION SBAT_VAR_LATEST_DATE \"\\n\" \\\n"
+	       "	SBAT_VAR_LATEST_REVOCATIONS\n\n"
 	       "#endif /* !ENABLE_SHIM_DEVEL */\n"
 	       "#endif /* !GEN_SBAT_VAR_DEFS_H_ */\n");
 
@@ -161,13 +202,12 @@ main(int argc, char *argv[])
 {
 	char SbatLevel_Variable[2048];
 
-	if (argc == 2)
+	if (argc >= 2)
 		snprintf(SbatLevel_Variable, 2048, "%s/SbatLevel_Variable.txt", argv[1]);
 	else
 		snprintf(SbatLevel_Variable, 2048, "SbatLevel_Variable.txt");
 
 	if (readfile(SbatLevel_Variable))
-		return writefile();
-	else
 		return -1;
+	return writefile();
 }