core: blob+stream: Store stream/blob hashes

Signed-off-by: Chloe M. <chloe@mirocom.org>

Makefile

@@ -8,6 +8,8 @@ DFILES = $(CFILES:.c=.d)
 OFILES = $(CFILES:.c=.o)
 
 CC = gcc
+LIBS = $(shell pkg-config --libs "openssl")
+
 CFLAGS =		\
 	-Wall		\
 	-pedantic	\
@@ -19,7 +21,7 @@ all: blobchain
 
 .PHONY: blobchain
 blobchain: $(OFILES)
-	$(CC) $^ -o $@
+	$(CC) $(LIBS) $^ -o $@
 
 -include $(DFILES)
 %.o: %.c

core/blob_list.c

@@ -3,11 +3,25 @@
  * Provided under the BSD-3 clause
  */
 
+#include <stdio.h>
 #include <errno.h>
 #include <stdlib.h>
 #include "blobchain/blob.h"
 #include "blobchain/memlib.h"
 
+static void
+dump_bytes(void *buf, size_t len)
+{
+    char *p = buf;
+    size_t i = 0;
+
+    while ((i++) < len) {
+        printf("%02X ", p[i] & 0xFF);
+    }
+
+    printf("\n");
+}
+
 int
 blob_list_init(struct blob_list *lp)
 {
@@ -65,3 +79,30 @@ blob_list_destroy(struct blob_list *lp)
         free(tmp);
     }
 }
+
+void
+blob_list_dump(struct blob_list *lp)
+{
+    const size_t DUMP_SIZE = 4;
+    struct blob *blob;
+    size_t count = 0;
+
+    if (lp == NULL) {
+        return;
+    }
+
+    blob = lp->head;
+    while (blob != NULL) {
+        printf("blob %zd/%zd\n", count++, lp->count);
+        printf("... length :: %zd\n", blob->length);
+        printf("... hash   :: ");
+        dump_bytes(blob->hash, SHA256_N_BYTES);
+
+        printf("... data   :: ");
+        dump_bytes(blob->data, blob->length < DUMP_SIZE
+            ? blob->length
+            : DUMP_SIZE);
+
+        blob = blob->next;
+    }
+}

core/blob_subr.c

@@ -14,6 +14,7 @@ blob_allocate(struct data_stream *stmp)
 
     bp = xmalloc(sizeof(*bp));
     bp->length = (stmp != NULL) ? stmp->length : 0;
+    bp->next = NULL;
     if (stmp == NULL) {
         bp->data = NULL;
     } else {
@@ -21,5 +22,6 @@ blob_allocate(struct data_stream *stmp)
         memcpy(bp->data, stmp->data, stmp->length);
     }
 
+    memcpy(bp->hash, stmp->hash, SHA256_N_BYTES);
     return bp;
 }

core/blobchain.c

@@ -12,6 +12,7 @@
 #include <dirent.h>
 #include "blobchain/common.h"
 #include "blobchain/stream.h"
+#include "blobchain/blob.h"
 
 /* Input directory path */
 static char *input_dir = NULL;
@@ -32,11 +33,13 @@ version(void)
 }
 
 static void
-pack_foreach(const char *input_dir)
+pack_foreach(struct blob_list *blobs, const char *input_dir)
 {
+    struct data_stream stream;
     char pathbuf[512];
     struct dirent *dirent;
     DIR *dir;
+    int error;
 
     if (input_dir == NULL) {
         return;
@@ -55,12 +58,27 @@ pack_foreach(const char *input_dir)
         switch (dirent->d_type) {
         case DT_DIR:
             snprintf(pathbuf, sizeof(pathbuf), "%s/%s", input_dir, dirent->d_name);
-            pack_foreach(pathbuf);
+            pack_foreach(blobs, pathbuf);
             printf("[d] %s\n", pathbuf);
             break;
         case DT_REG:
             snprintf(pathbuf, sizeof(pathbuf), "%s/%s", input_dir, dirent->d_name);
             printf("[r] %s\n", pathbuf);
+
+            error = stream_from_file(&stream, pathbuf);
+            if (error < 0) {
+                printf("fatal: could not create stream from '%s'\n", pathbuf);
+                return;
+            }
+
+            error = blob_list_append(blobs, blob_allocate(&stream));
+            if (error < 0) {
+                printf("fatal: failed to append blob '%s'\n", pathbuf);
+                stream_destroy(&stream);
+                continue;
+            }
+
+            stream_destroy(&stream);
             break;
         }
     }
@@ -70,6 +88,7 @@ static void
 pack_dir(void)
 {
     struct stat sb;
+    struct blob_list blobs;
 
     if (stat(input_dir, &sb) < 0) {
         perror("stat");
@@ -82,7 +101,16 @@ pack_dir(void)
         return;
     }
 
-    pack_foreach(input_dir);
+    if (blob_list_init(&blobs) < 0) {
+        printf("fatal: failed to initialize blob list...\n");
+        return;
+    }
+
+    pack_foreach(&blobs, input_dir);
+#if BLOBCHAIN_DEBUG
+    blob_list_dump(&blobs);
+#endif  /* BLOBCHAIN_DEBUG */
+    blob_list_destroy(&blobs);
 }
 
 int

core/stream_file.c

@@ -9,6 +9,7 @@
 #include <errno.h>
 #include <fcntl.h>
 #include <unistd.h>
+#include <openssl/sha.h>
 #include "blobchain/memlib.h"
 #include "blobchain/stream.h"
 
@@ -56,6 +57,7 @@ stream_from_file(struct data_stream *stmp, const char *path)
         return -1;
     }
 
+    SHA256(stmp->data, stmp->length, stmp->hash);
     return 0;
 }
 
@@ -66,6 +68,11 @@ stream_destroy(struct data_stream *stmp)
         return;
     }
 
+    if (stmp->data == NULL) {
+        return;
+    }
+
     free(stmp->data);
     stmp->length = 0;
+    stmp->data = NULL;
 }

inc/blobchain/blob.h

@@ -9,17 +9,20 @@
 #include <stdint.h>
 #include <stddef.h>
 #include "blobchain/stream.h"
+#include "blobchain/common.h"
 
 /*
  * Represents a single blob of data
  *
  * @data:   Buffer containing blob data
  * @length: Length of blob
+ * @hash:   Hash of file contents
  * @next:   Next blob
  */
 struct blob {
     void *data;
     size_t length;
+    uint8_t hash[SHA256_N_BYTES];
     struct blob *next;
 };
 
@@ -67,4 +70,11 @@ int blob_list_init(struct blob_list *lp);
  */
 void blob_list_destroy(struct blob_list *lp);
 
+/*
+ * Dump a blob list for debugging purposes
+ *
+ * @lp: Blob list to dump
+ */
+void blob_list_dump(struct blob_list *lp);
+
 #endif  /* !BLOBCHAIN_BLOB_H */

inc/blobchain/common.h

@@ -6,6 +6,9 @@
 #ifndef BLOBCHAIN_COMMON_H
 #define BLOBCHAIN_COMMON_H 1
 
+#define SHA256_N_BYTES 32
+
+#define BLOBCHAIN_DEBUG 1
 #define BLOBCHAIN_VERSION "0.0.1"
 
 #endif  /* !BLOBCHAIN_COMMON_H */

inc/blobchain/stream.h

@@ -6,17 +6,21 @@
 #ifndef BLOBCHAIN_STREAM_H
 #define BLOBCHAIN_STREAM_H 1
 
+#include <stdint.h>
 #include <stddef.h>
+#include "blobchain/common.h"
 
 /*
  * Represents a data stream
  *
  * @data:   Data buffer
  * @length: Number of bytes in data buffer
+ * @hash:   SHA256 hash of file contents
  */
 struct data_stream {
     void *data;
     size_t length;
+    uint8_t hash[SHA256_N_BYTES];
 };
 
 /*