tag.c

   1 #include "git-compat-util.h"
   2 #include "environment.h"
   3 #include "tag.h"
   4 #include "object-name.h"
   5 #include "object-store-ll.h"
   6 #include "commit.h"
   7 #include "tree.h"
   8 #include "blob.h"
   9 #include "alloc.h"
  10 #include "gpg-interface.h"
  11 #include "hex.h"
  12 #include "packfile.h"
  13
  14 const char *tag_type = "tag";
  15
  16 static int run_gpg_verify(const char *buf, unsigned long size, unsigned flags)
  17 {
  18         struct signature_check sigc;
  19         struct strbuf payload = STRBUF_INIT;
  20         struct strbuf signature = STRBUF_INIT;
  21         int ret;
  22
  23         memset(&sigc, 0, sizeof(sigc));
  24
  25         if (!parse_signature(buf, size, &payload, &signature)) {
  26                 if (flags & GPG_VERIFY_VERBOSE)
  27                         write_in_full(1, buf, size);
  28                 return error("no signature found");
  29         }
  30
  31         sigc.payload_type = SIGNATURE_PAYLOAD_TAG;
  32         sigc.payload = strbuf_detach(&payload, &sigc.payload_len);
  33         ret = check_signature(&sigc, signature.buf, signature.len);
  34
  35         if (!(flags & GPG_VERIFY_OMIT_STATUS))
  36                 print_signature_buffer(&sigc, flags);
  37
  38         signature_check_clear(&sigc);
  39         strbuf_release(&payload);
  40         strbuf_release(&signature);
  41         return ret;
  42 }
  43
  44 int gpg_verify_tag(const struct object_id *oid, const char *name_to_report,
  45                 unsigned flags)
  46 {
  47         enum object_type type;
  48         char *buf;
  49         unsigned long size;
  50         int ret;
  51
  52         type = oid_object_info(the_repository, oid, NULL);
  53         if (type != OBJ_TAG)
  54                 return error("%s: cannot verify a non-tag object of type %s.",
  55                                 name_to_report ?
  56                                 name_to_report :
  57                                 repo_find_unique_abbrev(the_repository, oid, DEFAULT_ABBREV),
  58                                 type_name(type));
  59
  60         buf = repo_read_object_file(the_repository, oid, &type, &size);
  61         if (!buf)
  62                 return error("%s: unable to read file.",
  63                                 name_to_report ?
  64                                 name_to_report :
  65                                 repo_find_unique_abbrev(the_repository, oid, DEFAULT_ABBREV));
  66
  67         ret = run_gpg_verify(buf, size, flags);
  68
  69         free(buf);
  70         return ret;
  71 }
  72
  73 struct object *deref_tag(struct repository *r, struct object *o, const char *warn, int warnlen)
  74 {
  75         struct object_id *last_oid = NULL;
  76         while (o && o->type == OBJ_TAG)
  77                 if (((struct tag *)o)->tagged) {
  78                         last_oid = &((struct tag *)o)->tagged->oid;
  79                         o = parse_object(r, last_oid);
  80                 } else {
  81                         last_oid = NULL;
  82                         o = NULL;
  83                 }
  84         if (!o && warn) {
  85                 if (last_oid && is_promisor_object(last_oid))
  86                         return NULL;
  87                 if (!warnlen)
  88                         warnlen = strlen(warn);
  89                 error("missing object referenced by '%.*s'", warnlen, warn);
  90         }
  91         return o;
  92 }
  93
  94 struct object *deref_tag_noverify(struct object *o)
  95 {
  96         while (o && o->type == OBJ_TAG) {
  97                 o = parse_object(the_repository, &o->oid);
  98                 if (o && o->type == OBJ_TAG && ((struct tag *)o)->tagged)
  99                         o = ((struct tag *)o)->tagged;
 100                 else
 101                         o = NULL;
 102         }
 103         return o;
 104 }
 105
 106 struct tag *lookup_tag(struct repository *r, const struct object_id *oid)
 107 {
 108         struct object *obj = lookup_object(r, oid);
 109         if (!obj)
 110                 return create_object(r, oid, alloc_tag_node(r));
 111         return object_as_type(obj, OBJ_TAG, 0);
 112 }
 113
 114 static timestamp_t parse_tag_date(const char *buf, const char *tail)
 115 {
 116         const char *dateptr;
 117
 118         while (buf < tail && *buf++ != '>')
 119                 /* nada */;
 120         if (buf >= tail)
 121                 return 0;
 122         dateptr = buf;
 123         while (buf < tail && *buf++ != '\n')
 124                 /* nada */;
 125         if (buf >= tail)
 126                 return 0;
 127         /* dateptr < buf && buf[-1] == '\n', so parsing will stop at buf-1 */
 128         return parse_timestamp(dateptr, NULL, 10);
 129 }
 130
 131 void release_tag_memory(struct tag *t)
 132 {
 133         free(t->tag);
 134         t->tagged = NULL;
 135         t->object.parsed = 0;
 136         t->date = 0;
 137 }
 138
 139 int parse_tag_buffer(struct repository *r, struct tag *item, const void *data, unsigned long size)
 140 {
 141         struct object_id oid;
 142         char type[20];
 143         const char *bufptr = data;
 144         const char *tail = bufptr + size;
 145         const char *nl;
 146
 147         if (item->object.parsed)
 148                 return 0;
 149
 150         if (item->tag) {
 151                 /*
 152                  * Presumably left over from a previous failed parse;
 153                  * clear it out in preparation for re-parsing (we'll probably
 154                  * hit the same error, which lets us tell our current caller
 155                  * about the problem).
 156                  */
 157                 FREE_AND_NULL(item->tag);
 158         }
 159
 160         if (size < the_hash_algo->hexsz + 24)
 161                 return -1;
 162         if (memcmp("object ", bufptr, 7) || parse_oid_hex(bufptr + 7, &oid, &bufptr) || *bufptr++ != '\n')
 163                 return -1;
 164
 165         if (!starts_with(bufptr, "type "))
 166                 return -1;
 167         bufptr += 5;
 168         nl = memchr(bufptr, '\n', tail - bufptr);
 169         if (!nl || sizeof(type) <= (nl - bufptr))
 170                 return -1;
 171         memcpy(type, bufptr, nl - bufptr);
 172         type[nl - bufptr] = '\0';
 173         bufptr = nl + 1;
 174
 175         if (!strcmp(type, blob_type)) {
 176                 item->tagged = (struct object *)lookup_blob(r, &oid);
 177         } else if (!strcmp(type, tree_type)) {
 178                 item->tagged = (struct object *)lookup_tree(r, &oid);
 179         } else if (!strcmp(type, commit_type)) {
 180                 item->tagged = (struct object *)lookup_commit(r, &oid);
 181         } else if (!strcmp(type, tag_type)) {
 182                 item->tagged = (struct object *)lookup_tag(r, &oid);
 183         } else {
 184                 return error("unknown tag type '%s' in %s",
 185                              type, oid_to_hex(&item->object.oid));
 186         }
 187
 188         if (!item->tagged)
 189                 return error("bad tag pointer to %s in %s",
 190                              oid_to_hex(&oid),
 191                              oid_to_hex(&item->object.oid));
 192
 193         if (bufptr + 4 < tail && starts_with(bufptr, "tag "))
 194                 ;               /* good */
 195         else
 196                 return -1;
 197         bufptr += 4;
 198         nl = memchr(bufptr, '\n', tail - bufptr);
 199         if (!nl)
 200                 return -1;
 201         item->tag = xmemdupz(bufptr, nl - bufptr);
 202         bufptr = nl + 1;
 203
 204         if (bufptr + 7 < tail && starts_with(bufptr, "tagger "))
 205                 item->date = parse_tag_date(bufptr, tail);
 206         else
 207                 item->date = 0;
 208
 209         item->object.parsed = 1;
 210         return 0;
 211 }
 212
 213 int parse_tag(struct tag *item)
 214 {
 215         enum object_type type;
 216         void *data;
 217         unsigned long size;
 218         int ret;
 219
 220         if (item->object.parsed)
 221                 return 0;
 222         data = repo_read_object_file(the_repository, &item->object.oid, &type,
 223                                      &size);
 224         if (!data)
 225                 return error("Could not read %s",
 226                              oid_to_hex(&item->object.oid));
 227         if (type != OBJ_TAG) {
 228                 free(data);
 229                 return error("Object %s not a tag",
 230                              oid_to_hex(&item->object.oid));
 231         }
 232         ret = parse_tag_buffer(the_repository, item, data, size);
 233         free(data);
 234         return ret;
 235 }
 236
 237 struct object_id *get_tagged_oid(struct tag *tag)
 238 {
 239         if (!tag->tagged)
 240                 die("bad tag");
 241         return &tag->tagged->oid;
 242 }