Fragment metadata checksumming support

include/erasurecode/erasurecode.h

@@ -256,15 +256,15 @@ int liberasurecode_fragments_needed(int desc,
 typedef struct __attribute__((__packed__))
 fragment_metadata
 {
-    uint32_t    idx;                /* 4 */
+    uint32_t    idx;                                     /*  4 */
-    uint32_t    size;               /* 4 */
+    uint32_t    size;                                    /*  4 */
-    uint32_t    frag_backend_metadata_size;    /* 4 */
+    uint32_t    frag_backend_metadata_size;              /*  4 */
-    uint64_t    orig_data_size;     /* 8 */
+    uint64_t    orig_data_size;                          /*  8 */
-    uint8_t     chksum_type;        /* 1 */
+    uint8_t     chksum_type;                             /*  1 */
     uint32_t    chksum[LIBERASURECODE_MAX_CHECKSUM_LEN]; /* 32 */
-    uint8_t     chksum_mismatch;    /* 1 */
+    uint8_t     chksum_mismatch;                         /*  1 */
-    uint8_t     backend_id;         /* 1 */
+    uint8_t     backend_id;                              /*  1 */
-    uint32_t    backend_version;    /* 4 */
+    uint32_t    backend_version;                         /*  4 */
 } fragment_metadata_t;
 
 /**
@@ -321,12 +321,13 @@ int liberasurecode_verify_stripe_metadata(int desc,
 
 typedef struct __attribute__((__packed__)) fragment_header_s
 {
-    fragment_metadata_t meta;   /* 59 bytes */
+    fragment_metadata_t meta;              /* 59 bytes */
-    uint32_t            magic;  /*  4 bytes */
+    uint32_t            magic;             /*  4 bytes */
-    uint32_t            libec_version; /* 4 bytes */
+    uint32_t            libec_version;     /*  4 bytes */
+    uint32_t            metadata_chksum;   /*  4 bytes */
     // We must be aligned to 16-byte boundaries
     // So, size this array accordingly
-    uint8_t             aligned_padding[13];
+    uint8_t             aligned_padding[9];
 } fragment_header_t;
 
 #define FRAGSIZE_2_BLOCKSIZE(fragment_size) \

include/erasurecode/erasurecode_helpers_ext.h

@@ -65,13 +65,16 @@ int get_fragment_buffer_size(char *buf);
 int set_orig_data_size(char *buf, int orig_data_size);
 int get_orig_data_size(char *buf);
 int set_checksum(ec_checksum_type_t ct, char *buf, int blocksize);
-int get_checksum(char *buf); //TODO implement this
+int get_checksum(char *buf);
 int set_libec_version(char *fragment);
 int get_libec_version(char *fragment, uint32_t *ver);
 int set_backend_id(char *buf, ec_backend_id_t id);
 int get_backend_id(char *buf, ec_backend_id_t *id);
 int set_backend_version(char *buf, uint32_t version);
 int get_backend_version(char *buf, uint32_t *version);
+int set_metadata_chksum(char *buf);
+uint32_t *get_metadata_chksum(char *buf);
+int is_invalid_fragment_header(fragment_header_t *header);
 
 /* ==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~== */
 

include/erasurecode/erasurecode_version.h

@@ -26,8 +26,8 @@
 #define _ERASURECODE_VERSION_H_
 
 #define _MAJOR 1
-#define _MINOR 1
+#define _MINOR 2
-#define _REV 2
+#define _REV 0
 #define _VERSION(x, y, z) ((x << 16) | (y << 8) | (z))
 
 #define LIBERASURECODE_VERSION _VERSION(_MAJOR, _MINOR, _REV)

src/erasurecode.c

@@ -26,6 +26,7 @@
  * vi: set noai tw=79 ts=4 sw=4:
  */
 
+#include "assert.h"
 #include "list.h"
 #include "erasurecode.h"
 #include "erasurecode_backend.h"
@@ -578,10 +579,22 @@ int liberasurecode_decode(int desc,
     m = instance->args.uargs.m;
 
     if (num_fragments < k) {
+        log_error("Not enough fragments to decode, got %d, need %d!",
+                  num_fragments, k);
         ret = -EINSUFFFRAGS;
         goto out;
     }
 
+    for (i = 0; i < num_fragments; ++i) {
+        /* Verify metadata checksum */
+        if (is_invalid_fragment_header(
+                (fragment_header_t *) available_fragments[i])) {
+            log_error("Invalid fragment header information!");
+            ret = -EBADHEADER;
+            goto out;
+        }
+    }
+
     if (instance->common.id != EC_BACKEND_SHSS) {
         /* shss (ntt_backend) must force to decode */
         // TODO: Add a frag and function to handle whether the backend want to decode or not.
@@ -783,6 +796,16 @@ int liberasurecode_reconstruct_fragment(int desc,
     k = instance->args.uargs.k;
     m = instance->args.uargs.m;
 
+    for (i = 0; i < num_fragments; i++) {
+        /* Verify metadata checksum */
+        if (is_invalid_fragment_header(
+                (fragment_header_t *) available_fragments[i])) {
+            log_error("Invalid fragment header information!");
+            ret = -EBADHEADER;
+            goto out;
+        }
+    }
+
     /*
      * Allocate arrays for data, parity and missing_idxs
      */
@@ -1004,6 +1027,14 @@ int liberasurecode_get_fragment_metadata(char *fragment,
         goto out;
     }
 
+    /* Verify metadata checksum */
+    if (is_invalid_fragment_header(
+            (fragment_header_t *) fragment)) {
+        log_error("Invalid fragment header information!");
+        ret = -EBADHEADER;
+        goto out;
+    }
+
     memcpy(fragment_metadata, fragment, sizeof(struct fragment_metadata));
     fragment_hdr = (fragment_header_t *) fragment;
     if (LIBERASURECODE_FRAG_HEADER_MAGIC != fragment_hdr->magic) {
@@ -1037,6 +1068,20 @@ out:
     return ret;
 }
 
+int is_invalid_fragment_header(fragment_header_t *header)
+{
+    uint32_t *stored_csum = NULL, csum = 0;
+    assert (NULL != header);
+    if (header->libec_version < _VERSION(1,2,0))
+        /* no metadata checksum support */
+        return 0;
+    stored_csum = get_metadata_chksum((char *) header);
+    if (NULL == stored_csum)
+        return 1; /* can't verify, possibly crc32 call error */
+    csum = crc32(0, &header->meta, sizeof(fragment_metadata_t));
+    return (*stored_csum != csum);
+}
+
 int liberasurecode_verify_fragment_metadata(ec_backend_t be,
                                             fragment_metadata_t *md)
 {
@@ -1054,6 +1099,27 @@ int liberasurecode_verify_fragment_metadata(ec_backend_t be,
     return 0;
 }
 
+int is_invalid_fragment_metadata(int desc, fragment_metadata_t *fragment_metadata)
+{
+    ec_backend_t be = liberasurecode_backend_instance_get_by_desc(desc);
+    if (!be) {
+        log_error("Unable to verify fragment metadata: invalid backend id %d.",
+                desc);
+        return -EINVALIDPARAMS;
+    }
+    if (liberasurecode_verify_fragment_metadata(be,
+            fragment_metadata) != 0) {
+        return -EBADHEADER;
+    }
+    if (!be->common.ops->is_compatible_with(fragment_metadata->backend_version))  {
+        return -EBADHEADER;
+    }
+    if (fragment_metadata->chksum_mismatch == 1) {
+        return -EBADCHKSUM;
+    }
+    return 0;
+}
+
 int is_invalid_fragment(int desc, char *fragment)
 {
     uint32_t ver = 0;
@@ -1069,41 +1135,18 @@ int is_invalid_fragment(int desc, char *fragment)
         return 1;
     }
     if (get_libec_version(fragment, &ver) != 0 ||
-            ver != LIBERASURECODE_VERSION) {
+            ver > LIBERASURECODE_VERSION) {
         return 1;
     }
-    if (liberasurecode_get_fragment_metadata(fragment,
+    if (liberasurecode_get_fragment_metadata(fragment, &fragment_metadata) != 0) {
-            &fragment_metadata) != 0) {
         return 1;
     }
-    if (liberasurecode_verify_fragment_metadata(be,
+    if (is_invalid_fragment_metadata(desc, &fragment_metadata) != 0) {
-            &fragment_metadata) != 0) {
         return 1;
     }
     return 0;
 }
 
-int is_valid_fragment_metadata(int desc, fragment_metadata_t *fragment_metadata)
-{
-    ec_backend_t be = liberasurecode_backend_instance_get_by_desc(desc);
-    if (!be) {
-        log_error("Unable to verify stripe metadata: invalid backend id %d.",
-                desc);
-        return -EINVALIDPARAMS;
-    }
-    if (liberasurecode_verify_fragment_metadata(be,
-            fragment_metadata) != 0) {
-        return -EBADHEADER;
-    }
-    if (!be->common.ops->is_compatible_with(fragment_metadata->backend_version))  {
-        return -EBADHEADER;
-    }
-    if (fragment_metadata->chksum_mismatch == 1) {
-        return -EBADCHKSUM;
-    }
-    return 0;
-}
-
 int liberasurecode_verify_stripe_metadata(int desc,
         char **fragments, int num_fragments)
 {
@@ -1120,7 +1163,7 @@ int liberasurecode_verify_stripe_metadata(int desc,
 
     for (i = 0; i < num_fragments; i++) {
         fragment_metadata_t *fragment_metadata = (fragment_metadata_t*)fragments[i];
-        int ret = is_valid_fragment_metadata(desc, fragment_metadata);
+        int ret = is_invalid_fragment_metadata(desc, fragment_metadata);
         if (ret < 0) {
             return ret;
         }

src/erasurecode_helpers.c

@@ -501,3 +501,45 @@ inline uint32_t* get_chksum(char *buf)
 
 /* ==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~== */
 
+#if LIBERASURECODE_VERSION >= _VERSION(1,2,0)
+inline int set_metadata_chksum(char *buf)
+{
+    fragment_header_t* header = (fragment_header_t*) buf;
+
+    assert(NULL != header);
+    if (header->magic != LIBERASURECODE_FRAG_HEADER_MAGIC) {
+        log_error("Invalid fragment header (set meta chksum)!\n");
+        return -1;
+    }
+
+    header->metadata_chksum = crc32(0, &header->meta,
+                                    sizeof(fragment_metadata_t));
+    return 0;
+}
+
+inline uint32_t* get_metadata_chksum(char *buf)
+{
+    fragment_header_t* header = (fragment_header_t*) buf;
+
+    assert(NULL != header);
+    if (header->magic != LIBERASURECODE_FRAG_HEADER_MAGIC) {
+        log_error("Invalid fragment header (get meta chksum)!");
+        return NULL;
+    }
+
+    return (uint32_t *) &header->metadata_chksum;
+}
+#else
+inline int set_metadata_chksum(char *buf)
+{
+    return 0;
+}
+
+inline uint32_t* get_metadata_chksum(char *buf)
+{
+    return (uint32_t *) 0;
+}
+#endif
+
+/* ==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~==~=*=~== */
+

src/erasurecode_postprocessing.c

@@ -47,6 +47,7 @@ void add_fragment_metadata(ec_backend_t be, char *fragment,
     if (add_chksum) {
         set_checksum(ct, fragment, blocksize);
     }
+    set_metadata_chksum(fragment);
 }
 
 int finalize_fragments_after_encode(ec_backend_t instance,

test/liberasurecode_test.c

@@ -940,17 +940,29 @@ static void encode_decode_test_impl(const ec_backend_id_t be_id,
     assert(0 == rc);
     orig_data_ptr = orig_data;
     remaining = orig_data_size;
-    for (i = 0; i < args->k; i++)
+    for (i = 0; i < args->k + args->m; i++)
     {
-        char *frag = encoded_data[i];
+        int cmp_size = -1;
+        char *data_ptr = NULL;
+        char *frag = NULL;
+        uint32_t *mcksum = NULL;
+
+        frag = (i < args->k) ? encoded_data[i] : encoded_parity[i - args->k];
+        assert(frag != NULL);
         fragment_header_t *header = (fragment_header_t*)frag;
         assert(header != NULL);
+        mcksum = get_metadata_chksum(frag);
+        assert(mcksum != NULL);
+        assert(header->metadata_chksum == *mcksum);
+
         fragment_metadata_t metadata = header->meta;
         assert(metadata.idx == i);
         assert(metadata.size == encoded_fragment_len - frag_header_size - be->common.backend_metadata_size);
         assert(metadata.orig_data_size == orig_data_size);
-        char *data_ptr = frag + frag_header_size;
+        assert(metadata.backend_id == be_id);
-        int cmp_size = remaining >= metadata.size ? metadata.size : remaining;
+        assert(metadata.chksum_mismatch == 0);
+        data_ptr = frag + frag_header_size;
+        cmp_size = remaining >= metadata.size ? metadata.size : remaining;
         // shss doesn't keep original data on data fragments
         if (be_id != EC_BACKEND_SHSS) {
             assert(memcmp(data_ptr, orig_data_ptr, cmp_size) == 0);