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