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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-09 13:34:27 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-09 13:34:27 +0000
commit4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f (patch)
tree47c1d492e9c956c1cd2b74dbd3b9d8b0db44dc4e /pack-check.c
parentInitial commit. (diff)
downloadgit-4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f.tar.xz
git-4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f.zip
Adding upstream version 1:2.43.0.upstream/1%2.43.0
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'pack-check.c')
-rw-r--r--pack-check.c200
1 files changed, 200 insertions, 0 deletions
diff --git a/pack-check.c b/pack-check.c
new file mode 100644
index 0000000..977f619
--- /dev/null
+++ b/pack-check.c
@@ -0,0 +1,200 @@
+#include "git-compat-util.h"
+#include "environment.h"
+#include "hex.h"
+#include "repository.h"
+#include "pack.h"
+#include "pack-revindex.h"
+#include "progress.h"
+#include "packfile.h"
+#include "object-file.h"
+#include "object-store-ll.h"
+
+struct idx_entry {
+ off_t offset;
+ unsigned int nr;
+};
+
+static int compare_entries(const void *e1, const void *e2)
+{
+ const struct idx_entry *entry1 = e1;
+ const struct idx_entry *entry2 = e2;
+ if (entry1->offset < entry2->offset)
+ return -1;
+ if (entry1->offset > entry2->offset)
+ return 1;
+ return 0;
+}
+
+int check_pack_crc(struct packed_git *p, struct pack_window **w_curs,
+ off_t offset, off_t len, unsigned int nr)
+{
+ const uint32_t *index_crc;
+ uint32_t data_crc = crc32(0, NULL, 0);
+
+ do {
+ unsigned long avail;
+ void *data = use_pack(p, w_curs, offset, &avail);
+ if (avail > len)
+ avail = len;
+ data_crc = crc32(data_crc, data, avail);
+ offset += avail;
+ len -= avail;
+ } while (len);
+
+ index_crc = p->index_data;
+ index_crc += 2 + 256 + (size_t)p->num_objects * (the_hash_algo->rawsz/4) + nr;
+
+ return data_crc != ntohl(*index_crc);
+}
+
+static int verify_packfile(struct repository *r,
+ struct packed_git *p,
+ struct pack_window **w_curs,
+ verify_fn fn,
+ struct progress *progress, uint32_t base_count)
+
+{
+ off_t index_size = p->index_size;
+ const unsigned char *index_base = p->index_data;
+ git_hash_ctx ctx;
+ unsigned char hash[GIT_MAX_RAWSZ], *pack_sig;
+ off_t offset = 0, pack_sig_ofs = 0;
+ uint32_t nr_objects, i;
+ int err = 0;
+ struct idx_entry *entries;
+
+ if (!is_pack_valid(p))
+ return error("packfile %s cannot be accessed", p->pack_name);
+
+ r->hash_algo->init_fn(&ctx);
+ do {
+ unsigned long remaining;
+ unsigned char *in = use_pack(p, w_curs, offset, &remaining);
+ offset += remaining;
+ if (!pack_sig_ofs)
+ pack_sig_ofs = p->pack_size - r->hash_algo->rawsz;
+ if (offset > pack_sig_ofs)
+ remaining -= (unsigned int)(offset - pack_sig_ofs);
+ r->hash_algo->update_fn(&ctx, in, remaining);
+ } while (offset < pack_sig_ofs);
+ r->hash_algo->final_fn(hash, &ctx);
+ pack_sig = use_pack(p, w_curs, pack_sig_ofs, NULL);
+ if (!hasheq(hash, pack_sig))
+ err = error("%s pack checksum mismatch",
+ p->pack_name);
+ if (!hasheq(index_base + index_size - r->hash_algo->hexsz, pack_sig))
+ err = error("%s pack checksum does not match its index",
+ p->pack_name);
+ unuse_pack(w_curs);
+
+ /* Make sure everything reachable from idx is valid. Since we
+ * have verified that nr_objects matches between idx and pack,
+ * we do not do scan-streaming check on the pack file.
+ */
+ nr_objects = p->num_objects;
+ ALLOC_ARRAY(entries, nr_objects + 1);
+ entries[nr_objects].offset = pack_sig_ofs;
+ /* first sort entries by pack offset, since unpacking them is more efficient that way */
+ for (i = 0; i < nr_objects; i++) {
+ entries[i].offset = nth_packed_object_offset(p, i);
+ entries[i].nr = i;
+ }
+ QSORT(entries, nr_objects, compare_entries);
+
+ for (i = 0; i < nr_objects; i++) {
+ void *data;
+ struct object_id oid;
+ enum object_type type;
+ unsigned long size;
+ off_t curpos;
+ int data_valid;
+
+ if (nth_packed_object_id(&oid, p, entries[i].nr) < 0)
+ BUG("unable to get oid of object %lu from %s",
+ (unsigned long)entries[i].nr, p->pack_name);
+
+ if (p->index_version > 1) {
+ off_t offset = entries[i].offset;
+ off_t len = entries[i+1].offset - offset;
+ unsigned int nr = entries[i].nr;
+ if (check_pack_crc(p, w_curs, offset, len, nr))
+ err = error("index CRC mismatch for object %s "
+ "from %s at offset %"PRIuMAX"",
+ oid_to_hex(&oid),
+ p->pack_name, (uintmax_t)offset);
+ }
+
+ curpos = entries[i].offset;
+ type = unpack_object_header(p, w_curs, &curpos, &size);
+ unuse_pack(w_curs);
+
+ if (type == OBJ_BLOB && big_file_threshold <= size) {
+ /*
+ * Let stream_object_signature() check it with
+ * the streaming interface; no point slurping
+ * the data in-core only to discard.
+ */
+ data = NULL;
+ data_valid = 0;
+ } else {
+ data = unpack_entry(r, p, entries[i].offset, &type, &size);
+ data_valid = 1;
+ }
+
+ if (data_valid && !data)
+ err = error("cannot unpack %s from %s at offset %"PRIuMAX"",
+ oid_to_hex(&oid), p->pack_name,
+ (uintmax_t)entries[i].offset);
+ else if (data && check_object_signature(r, &oid, data, size,
+ type) < 0)
+ err = error("packed %s from %s is corrupt",
+ oid_to_hex(&oid), p->pack_name);
+ else if (!data && stream_object_signature(r, &oid) < 0)
+ err = error("packed %s from %s is corrupt",
+ oid_to_hex(&oid), p->pack_name);
+ else if (fn) {
+ int eaten = 0;
+ err |= fn(&oid, type, size, data, &eaten);
+ if (eaten)
+ data = NULL;
+ }
+ if (((base_count + i) & 1023) == 0)
+ display_progress(progress, base_count + i);
+ free(data);
+
+ }
+ display_progress(progress, base_count + i);
+ free(entries);
+
+ return err;
+}
+
+int verify_pack_index(struct packed_git *p)
+{
+ int err = 0;
+
+ if (open_pack_index(p))
+ return error("packfile %s index not opened", p->pack_name);
+
+ /* Verify SHA1 sum of the index file */
+ if (!hashfile_checksum_valid(p->index_data, p->index_size))
+ err = error("Packfile index for %s hash mismatch",
+ p->pack_name);
+ return err;
+}
+
+int verify_pack(struct repository *r, struct packed_git *p, verify_fn fn,
+ struct progress *progress, uint32_t base_count)
+{
+ int err = 0;
+ struct pack_window *w_curs = NULL;
+
+ err |= verify_pack_index(p);
+ if (!p->index_data)
+ return -1;
+
+ err |= verify_packfile(r, p, &w_curs, fn, progress, base_count);
+ unuse_pack(&w_curs);
+
+ return err;
+}