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