tag.c

   1 #include "cache.h"
   2 #include "tag.h"
   3 #include "object-store.h"
   4 #include "commit.h"
   5 #include "tree.h"
   6 #include "blob.h"
   7 #include "alloc.h"
   8 #include "gpg-interface.h"
   9 #include "hex.h"
  10 #include "packfile.h"
  11
  12 const char *tag_type = "tag";
  13
  14 static int run_gpg_verify(const char *buf, unsigned long size, unsigned flags)
  15 {
  16         struct signature_check sigc;
  17         struct strbuf payload = STRBUF_INIT;
  18         struct strbuf signature = STRBUF_INIT;
  19         int ret;
  20
  21         memset(&sigc, 0, sizeof(sigc));
  22
  23         if (!parse_signature(buf, size, &payload, &signature)) {
  24                 if (flags & GPG_VERIFY_VERBOSE)
  25                         write_in_full(1, buf, size);
  26                 return error("no signature found");
  27         }
  28
  29         sigc.payload_type = SIGNATURE_PAYLOAD_TAG;
  30         sigc.payload = strbuf_detach(&payload, &sigc.payload_len);
  31         ret = check_signature(&sigc, signature.buf, signature.len);
  32
  33         if (!(flags & GPG_VERIFY_OMIT_STATUS))
  34                 print_signature_buffer(&sigc, flags);
  35
  36         signature_check_clear(&sigc);
  37         strbuf_release(&payload);
  38         strbuf_release(&signature);
  39         return ret;
  40 }
  41
  42 int gpg_verify_tag(const struct object_id *oid, const char *name_to_report,
  43                 unsigned flags)
  44 {
  45         enum object_type type;
  46         char *buf;
  47         unsigned long size;
  48         int ret;
  49
  50         type = oid_object_info(the_repository, oid, NULL);
  51         if (type != OBJ_TAG)
  52                 return error("%s: cannot verify a non-tag object of type %s.",
  53                                 name_to_report ?
  54                                 name_to_report :
  55                                 find_unique_abbrev(oid, DEFAULT_ABBREV),
  56                                 type_name(type));
  57
  58         buf = read_object_file(oid, &type, &size);
  59         if (!buf)
  60                 return error("%s: unable to read file.",
  61                                 name_to_report ?
  62                                 name_to_report :
  63                                 find_unique_abbrev(oid, DEFAULT_ABBREV));
  64
  65         ret = run_gpg_verify(buf, size, flags);
  66
  67         free(buf);
  68         return ret;
  69 }
  70
  71 struct object *deref_tag(struct repository *r, struct object *o, const char *warn, int warnlen)
  72 {
  73         struct object_id *last_oid = NULL;
  74         while (o && o->type == OBJ_TAG)
  75                 if (((struct tag *)o)->tagged) {
  76                         last_oid = &((struct tag *)o)->tagged->oid;
  77                         o = parse_object(r, last_oid);
  78                 } else {
  79                         last_oid = NULL;
  80                         o = NULL;
  81                 }
  82         if (!o && warn) {
  83                 if (last_oid && is_promisor_object(last_oid))
  84                         return NULL;
  85                 if (!warnlen)
  86                         warnlen = strlen(warn);
  87                 error("missing object referenced by '%.*s'", warnlen, warn);
  88         }
  89         return o;
  90 }
  91
  92 struct object *deref_tag_noverify(struct object *o)
  93 {
  94         while (o && o->type == OBJ_TAG) {
  95                 o = parse_object(the_repository, &o->oid);
  96                 if (o && o->type == OBJ_TAG && ((struct tag *)o)->tagged)
  97                         o = ((struct tag *)o)->tagged;
  98                 else
  99                         o = NULL;
 100         }
 101         return o;
 102 }
 103
 104 struct tag *lookup_tag(struct repository *r, const struct object_id *oid)
 105 {
 106         struct object *obj = lookup_object(r, oid);
 107         if (!obj)
 108                 return create_object(r, oid, alloc_tag_node(r));
 109         return object_as_type(obj, OBJ_TAG, 0);
 110 }
 111
 112 static timestamp_t parse_tag_date(const char *buf, const char *tail)
 113 {
 114         const char *dateptr;
 115
 116         while (buf < tail && *buf++ != '>')
 117                 /* nada */;
 118         if (buf >= tail)
 119                 return 0;
 120         dateptr = buf;
 121         while (buf < tail && *buf++ != '\n')
 122                 /* nada */;
 123         if (buf >= tail)
 124                 return 0;
 125         /* dateptr < buf && buf[-1] == '\n', so parsing will stop at buf-1 */
 126         return parse_timestamp(dateptr, NULL, 10);
 127 }
 128
 129 void release_tag_memory(struct tag *t)
 130 {
 131         free(t->tag);
 132         t->tagged = NULL;
 133         t->object.parsed = 0;
 134         t->date = 0;
 135 }
 136
 137 int parse_tag_buffer(struct repository *r, struct tag *item, const void *data, unsigned long size)
 138 {
 139         struct object_id oid;
 140         char type[20];
 141         const char *bufptr = data;
 142         const char *tail = bufptr + size;
 143         const char *nl;
 144
 145         if (item->object.parsed)
 146                 return 0;
 147
 148         if (item->tag) {
 149                 /*
 150                  * Presumably left over from a previous failed parse;
 151                  * clear it out in preparation for re-parsing (we'll probably
 152                  * hit the same error, which lets us tell our current caller
 153                  * about the problem).
 154                  */
 155                 FREE_AND_NULL(item->tag);
 156         }
 157
 158         if (size < the_hash_algo->hexsz + 24)
 159                 return -1;
 160         if (memcmp("object ", bufptr, 7) || parse_oid_hex(bufptr + 7, &oid, &bufptr) || *bufptr++ != '\n')
 161                 return -1;
 162
 163         if (!starts_with(bufptr, "type "))
 164                 return -1;
 165         bufptr += 5;
 166         nl = memchr(bufptr, '\n', tail - bufptr);
 167         if (!nl || sizeof(type) <= (nl - bufptr))
 168                 return -1;
 169         memcpy(type, bufptr, nl - bufptr);
 170         type[nl - bufptr] = '\0';
 171         bufptr = nl + 1;
 172
 173         if (!strcmp(type, blob_type)) {
 174                 item->tagged = (struct object *)lookup_blob(r, &oid);
 175         } else if (!strcmp(type, tree_type)) {
 176                 item->tagged = (struct object *)lookup_tree(r, &oid);
 177         } else if (!strcmp(type, commit_type)) {
 178                 item->tagged = (struct object *)lookup_commit(r, &oid);
 179         } else if (!strcmp(type, tag_type)) {
 180                 item->tagged = (struct object *)lookup_tag(r, &oid);
 181         } else {
 182                 return error("unknown tag type '%s' in %s",
 183                              type, oid_to_hex(&item->object.oid));
 184         }
 185
 186         if (!item->tagged)
 187                 return error("bad tag pointer to %s in %s",
 188                              oid_to_hex(&oid),
 189                              oid_to_hex(&item->object.oid));
 190
 191         if (bufptr + 4 < tail && starts_with(bufptr, "tag "))
 192                 ;               /* good */
 193         else
 194                 return -1;
 195         bufptr += 4;
 196         nl = memchr(bufptr, '\n', tail - bufptr);
 197         if (!nl)
 198                 return -1;
 199         item->tag = xmemdupz(bufptr, nl - bufptr);
 200         bufptr = nl + 1;
 201
 202         if (bufptr + 7 < tail && starts_with(bufptr, "tagger "))
 203                 item->date = parse_tag_date(bufptr, tail);
 204         else
 205                 item->date = 0;
 206
 207         item->object.parsed = 1;
 208         return 0;
 209 }
 210
 211 int parse_tag(struct tag *item)
 212 {
 213         enum object_type type;
 214         void *data;
 215         unsigned long size;
 216         int ret;
 217
 218         if (item->object.parsed)
 219                 return 0;
 220         data = read_object_file(&item->object.oid, &type, &size);
 221         if (!data)
 222                 return error("Could not read %s",
 223                              oid_to_hex(&item->object.oid));
 224         if (type != OBJ_TAG) {
 225                 free(data);
 226                 return error("Object %s not a tag",
 227                              oid_to_hex(&item->object.oid));
 228         }
 229         ret = parse_tag_buffer(the_repository, item, data, size);
 230         free(data);
 231         return ret;
 232 }
 233
 234 struct object_id *get_tagged_oid(struct tag *tag)
 235 {
 236         if (!tag->tagged)
 237                 die("bad tag");
 238         return &tag->tagged->oid;
 239 }