builtin/credential-store.c

   1 #include "builtin.h"
   2 #include "config.h"
   3 #include "gettext.h"
   4 #include "lockfile.h"
   5 #include "credential.h"
   6 #include "path.h"
   7 #include "string-list.h"
   8 #include "parse-options.h"
   9 #include "write-or-die.h"
  10
  11 static struct lock_file credential_lock;
  12
  13 static int parse_credential_file(const char *fn,
  14                                   struct credential *c,
  15                                   void (*match_cb)(struct credential *),
  16                                   void (*other_cb)(struct strbuf *),
  17                                   int match_password)
  18 {
  19         FILE *fh;
  20         struct strbuf line = STRBUF_INIT;
  21         struct credential entry = CREDENTIAL_INIT;
  22         int found_credential = 0;
  23
  24         fh = fopen(fn, "r");
  25         if (!fh) {
  26                 if (errno != ENOENT && errno != EACCES)
  27                         die_errno("unable to open %s", fn);
  28                 return found_credential;
  29         }
  30
  31         while (strbuf_getline_lf(&line, fh) != EOF) {
  32                 if (!credential_from_url_gently(&entry, line.buf, 1) &&
  33                     entry.username && entry.password &&
  34                     credential_match(c, &entry, match_password)) {
  35                         found_credential = 1;
  36                         if (match_cb) {
  37                                 match_cb(&entry);
  38                                 break;
  39                         }
  40                 }
  41                 else if (other_cb)
  42                         other_cb(&line);
  43         }
  44
  45         credential_clear(&entry);
  46         strbuf_release(&line);
  47         fclose(fh);
  48         return found_credential;
  49 }
  50
  51 static void print_entry(struct credential *c)
  52 {
  53         printf("username=%s\n", c->username);
  54         printf("password=%s\n", c->password);
  55 }
  56
  57 static void print_line(struct strbuf *buf)
  58 {
  59         strbuf_addch(buf, '\n');
  60         write_or_die(get_lock_file_fd(&credential_lock), buf->buf, buf->len);
  61 }
  62
  63 static void rewrite_credential_file(const char *fn, struct credential *c,
  64                                     struct strbuf *extra, int match_password)
  65 {
  66         int timeout_ms = 1000;
  67
  68         git_config_get_int("credentialstore.locktimeoutms", &timeout_ms);
  69         if (hold_lock_file_for_update_timeout(&credential_lock, fn, 0, timeout_ms) < 0)
  70                 die_errno(_("unable to get credential storage lock in %d ms"), timeout_ms);
  71         if (extra)
  72                 print_line(extra);
  73         parse_credential_file(fn, c, NULL, print_line, match_password);
  74         if (commit_lock_file(&credential_lock) < 0)
  75                 die_errno("unable to write credential store");
  76 }
  77
  78 static void store_credential_file(const char *fn, struct credential *c)
  79 {
  80         struct strbuf buf = STRBUF_INIT;
  81
  82         strbuf_addf(&buf, "%s://", c->protocol);
  83         strbuf_addstr_urlencode(&buf, c->username, is_rfc3986_unreserved);
  84         strbuf_addch(&buf, ':');
  85         strbuf_addstr_urlencode(&buf, c->password, is_rfc3986_unreserved);
  86         strbuf_addch(&buf, '@');
  87         if (c->host)
  88                 strbuf_addstr_urlencode(&buf, c->host, is_rfc3986_unreserved);
  89         if (c->path) {
  90                 strbuf_addch(&buf, '/');
  91                 strbuf_addstr_urlencode(&buf, c->path,
  92                                         is_rfc3986_reserved_or_unreserved);
  93         }
  94
  95         rewrite_credential_file(fn, c, &buf, 0);
  96         strbuf_release(&buf);
  97 }
  98
  99 static void store_credential(const struct string_list *fns, struct credential *c)
 100 {
 101         struct string_list_item *fn;
 102
 103         /*
 104          * Sanity check that what we are storing is actually sensible.
 105          * In particular, we can't make a URL without a protocol field.
 106          * Without either a host or pathname (depending on the scheme),
 107          * we have no primary key. And without a username and password,
 108          * we are not actually storing a credential.
 109          */
 110         if (!c->protocol || !(c->host || c->path) || !c->username || !c->password)
 111                 return;
 112
 113         for_each_string_list_item(fn, fns)
 114                 if (!access(fn->string, F_OK)) {
 115                         store_credential_file(fn->string, c);
 116                         return;
 117                 }
 118         /*
 119          * Write credential to the filename specified by fns->items[0], thus
 120          * creating it
 121          */
 122         if (fns->nr)
 123                 store_credential_file(fns->items[0].string, c);
 124 }
 125
 126 static void remove_credential(const struct string_list *fns, struct credential *c)
 127 {
 128         struct string_list_item *fn;
 129
 130         /*
 131          * Sanity check that we actually have something to match
 132          * against. The input we get is a restrictive pattern,
 133          * so technically a blank credential means "erase everything".
 134          * But it is too easy to accidentally send this, since it is equivalent
 135          * to empty input. So explicitly disallow it, and require that the
 136          * pattern have some actual content to match.
 137          */
 138         if (!c->protocol && !c->host && !c->path && !c->username)
 139                 return;
 140         for_each_string_list_item(fn, fns)
 141                 if (!access(fn->string, F_OK))
 142                         rewrite_credential_file(fn->string, c, NULL, 1);
 143 }
 144
 145 static void lookup_credential(const struct string_list *fns, struct credential *c)
 146 {
 147         struct string_list_item *fn;
 148
 149         for_each_string_list_item(fn, fns)
 150                 if (parse_credential_file(fn->string, c, print_entry, NULL, 0))
 151                         return; /* Found credential */
 152 }
 153
 154 int cmd_credential_store(int argc, const char **argv, const char *prefix)
 155 {
 156         const char * const usage[] = {
 157                 "git credential-store [<options>] <action>",
 158                 NULL
 159         };
 160         const char *op;
 161         struct credential c = CREDENTIAL_INIT;
 162         struct string_list fns = STRING_LIST_INIT_DUP;
 163         char *file = NULL;
 164         struct option options[] = {
 165                 OPT_STRING(0, "file", &file, "path",
 166                            "fetch and store credentials in <path>"),
 167                 OPT_END()
 168         };
 169
 170         umask(077);
 171
 172         argc = parse_options(argc, (const char **)argv, prefix, options, usage, 0);
 173         if (argc != 1)
 174                 usage_with_options(usage, options);
 175         op = argv[0];
 176
 177         if (file) {
 178                 string_list_append(&fns, file);
 179         } else {
 180                 if ((file = interpolate_path("~/.git-credentials", 0)))
 181                         string_list_append_nodup(&fns, file);
 182                 file = xdg_config_home("credentials");
 183                 if (file)
 184                         string_list_append_nodup(&fns, file);
 185         }
 186         if (!fns.nr)
 187                 die("unable to set up default path; use --file");
 188
 189         if (credential_read(&c, stdin) < 0)
 190                 die("unable to read credential");
 191
 192         if (!strcmp(op, "get"))
 193                 lookup_credential(&fns, &c);
 194         else if (!strcmp(op, "erase"))
 195                 remove_credential(&fns, &c);
 196         else if (!strcmp(op, "store"))
 197                 store_credential(&fns, &c);
 198         else
 199                 ; /* Ignore unknown operation. */
 200
 201         string_list_clear(&fns, 0);
 202         return 0;
 203 }