From 1570d3dbe3777e58bb773dacd205f215753d11e7 Mon Sep 17 00:00:00 2001
From: Jarrod Johnson <jjohnson2@lenovo.com>
Date: Thu, 15 Jul 2021 12:39:19 -0400
Subject: [PATCH] Add c utility for reading confluent multipart images

---
 confluent_osdeploy/utils/confluent_imginfo.c | 70 ++++++++++++++++++++
 1 file changed, 70 insertions(+)
 create mode 100644 confluent_osdeploy/utils/confluent_imginfo.c

diff --git a/confluent_osdeploy/utils/confluent_imginfo.c b/confluent_osdeploy/utils/confluent_imginfo.c
new file mode 100644
index 00000000..fe8f1c9a
--- /dev/null
+++ b/confluent_osdeploy/utils/confluent_imginfo.c
@@ -0,0 +1,70 @@
+#include <stdint.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+int read_part(FILE* img, long int imgsize) {
+    char mountpath[65537];
+    char devpath[65537];
+    char fstype[65537];
+    uint16_t shortlength;
+    uint32_t length;
+    uint64_t longlength;
+    fread(&shortlength, 2, 1, img);
+    shortlength = be16toh(shortlength);
+    fread(mountpath, 1, shortlength, img);
+    mountpath[shortlength] = 0;
+    fread(&length, 4, 1, img);
+    length = be32toh(length);
+    fseek(img, length, SEEK_CUR); // skip json section that we don't support
+    fread(&longlength, 8, 1, img); // minimum size in bytes
+    longlength = be64toh(longlength);
+    printf("%ld\t", longlength);
+    fread(&longlength, 8, 1, img); // default size in bytes
+    longlength = be64toh(longlength);
+    printf("%ld\t", longlength);
+    fread(&shortlength, 2, 1, img); // length of filesystem type
+    shortlength = be16toh(shortlength);
+    fread(fstype, 1, shortlength, img);
+    fstype[shortlength] = 0;
+    fread(&shortlength, 2, 1, img); // length of DEVICE
+    shortlength = be16toh(shortlength);
+    fread(devpath, 1, shortlength, img);
+    devpath[shortlength] = 0;
+    fread(&shortlength, 2, 1, img);
+    shortlength = be16toh(shortlength);
+    fseek(img, shortlength, SEEK_CUR); // Skip the padding
+    fread(&longlength, 8, 1, img);
+    longlength = be64toh(longlength);
+    printf("%ld\t", ftell(img) / 512);
+    printf("%ld\t", longlength / 512);
+    printf("%s\t%s\t%s\n", fstype, devpath, mountpath);
+    fseek(img, longlength, SEEK_CUR);
+    return (ftell(img) < imgsize);
+}
+
+int main(int argc, char* argv[]) {
+    FILE* img;
+    long int imgsize;
+    char buffer[20];
+
+    img = fopen(argv[1], "rb");
+    fseek(img, 0, SEEK_END);
+    imgsize = ftell(img);
+    fseek(img, 0, SEEK_SET);
+    if (fread(buffer, 1, 16, img) < 16) {
+        fprintf(stderr, "Unable to read header of image\n");
+        exit(1);
+    }
+    if ((memcmp(buffer, "hsqs", 4) == 0) || (memcmp(buffer, "sqsh", 4) == 0)) {
+        printf("Format: squashfs\n");
+        exit(0);
+    }
+    if (memcmp(buffer, "\x63\x7b\x9d\x26\xb7\xfd\x48\x30\x89\xf9\x11\xcf\x18\xfd\xff\xa1", 16) != 0) {
+        fprintf(stderr, "Unrecognized image format\n");
+        exit(1);
+    }
+    printf("Format: confluent_multisquash\nminsize\tdefsize\toffset\tsize\tfstype\torigdev\tmount\n");
+    fseek(img, 31, SEEK_SET);
+    while (read_part(img, imgsize));
+}