contrib/credential/osxkeychain/git-credential-osxkeychain.c

   1 #include <stdio.h>
   2 #include <string.h>
   3 #include <stdlib.h>
   4 #include <Security/Security.h>
   5
   6 static SecProtocolType protocol;
   7 static char *host;
   8 static char *path;
   9 static char *username;
  10 static char *password;
  11 static UInt16 port;
  12
  13 static void die(const char *err, ...)
  14 {
  15         char msg[4096];
  16         va_list params;
  17         va_start(params, err);
  18         vsnprintf(msg, sizeof(msg), err, params);
  19         fprintf(stderr, "%s\n", msg);
  20         va_end(params);
  21         exit(1);
  22 }
  23
  24 static void *xstrdup(const char *s1)
  25 {
  26         void *ret = strdup(s1);
  27         if (!ret)
  28                 die("Out of memory");
  29         return ret;
  30 }
  31
  32 #define KEYCHAIN_ITEM(x) (x ? strlen(x) : 0), x
  33 #define KEYCHAIN_ARGS \
  34         NULL, /* default keychain */ \
  35         KEYCHAIN_ITEM(host), \
  36         0, NULL, /* account domain */ \
  37         KEYCHAIN_ITEM(username), \
  38         KEYCHAIN_ITEM(path), \
  39         port, \
  40         protocol, \
  41         kSecAuthenticationTypeDefault
  42
  43 static void write_item(const char *what, const char *buf, int len)
  44 {
  45         printf("%s=", what);
  46         fwrite(buf, 1, len, stdout);
  47         putchar('\n');
  48 }
  49
  50 static void find_username_in_item(SecKeychainItemRef item)
  51 {
  52         SecKeychainAttributeList list;
  53         SecKeychainAttribute attr;
  54
  55         list.count = 1;
  56         list.attr = &attr;
  57         attr.tag = kSecAccountItemAttr;
  58
  59         if (SecKeychainItemCopyContent(item, NULL, &list, NULL, NULL))
  60                 return;
  61
  62         write_item("username", attr.data, attr.length);
  63         SecKeychainItemFreeContent(&list, NULL);
  64 }
  65
  66 static void find_internet_password(void)
  67 {
  68         void *buf;
  69         UInt32 len;
  70         SecKeychainItemRef item;
  71
  72         if (SecKeychainFindInternetPassword(KEYCHAIN_ARGS, &len, &buf, &item))
  73                 return;
  74
  75         write_item("password", buf, len);
  76         if (!username)
  77                 find_username_in_item(item);
  78
  79         SecKeychainItemFreeContent(NULL, buf);
  80 }
  81
  82 static void delete_internet_password(void)
  83 {
  84         SecKeychainItemRef item;
  85
  86         /*
  87          * Require at least a protocol and host for removal, which is what git
  88          * will give us; if you want to do something more fancy, use the
  89          * Keychain manager.
  90          */
  91         if (!protocol || !host)
  92                 return;
  93
  94         if (SecKeychainFindInternetPassword(KEYCHAIN_ARGS, 0, NULL, &item))
  95                 return;
  96
  97         SecKeychainItemDelete(item);
  98 }
  99
 100 static void add_internet_password(void)
 101 {
 102         /* Only store complete credentials */
 103         if (!protocol || !host || !username || !password)
 104                 return;
 105
 106         if (SecKeychainAddInternetPassword(
 107               KEYCHAIN_ARGS,
 108               KEYCHAIN_ITEM(password),
 109               NULL))
 110                 return;
 111 }
 112
 113 static void read_credential(void)
 114 {
 115         char buf[1024];
 116
 117         while (fgets(buf, sizeof(buf), stdin)) {
 118                 char *v;
 119
 120                 if (!strcmp(buf, "\n"))
 121                         break;
 122                 buf[strlen(buf)-1] = '\0';
 123
 124                 v = strchr(buf, '=');
 125                 if (!v)
 126                         die("bad input: %s", buf);
 127                 *v++ = '\0';
 128
 129                 if (!strcmp(buf, "protocol")) {
 130                         if (!strcmp(v, "https"))
 131                                 protocol = kSecProtocolTypeHTTPS;
 132                         else if (!strcmp(v, "http"))
 133                                 protocol = kSecProtocolTypeHTTP;
 134                         else /* we don't yet handle other protocols */
 135                                 exit(0);
 136                 }
 137                 else if (!strcmp(buf, "host")) {
 138                         char *colon = strchr(v, ':');
 139                         if (colon) {
 140                                 *colon++ = '\0';
 141                                 port = atoi(colon);
 142                         }
 143                         host = xstrdup(v);
 144                 }
 145                 else if (!strcmp(buf, "path"))
 146                         path = xstrdup(v);
 147                 else if (!strcmp(buf, "username"))
 148                         username = xstrdup(v);
 149                 else if (!strcmp(buf, "password"))
 150                         password = xstrdup(v);
 151         }
 152 }
 153
 154 int main(int argc, const char **argv)
 155 {
 156         const char *usage =
 157                 "Usage: git credential-osxkeychain <get|store|erase>";
 158
 159         if (!argv[1])
 160                 die(usage);
 161
 162         read_credential();
 163
 164         if (!strcmp(argv[1], "get"))
 165                 find_internet_password();
 166         else if (!strcmp(argv[1], "store"))
 167                 add_internet_password();
 168         else if (!strcmp(argv[1], "erase"))
 169                 delete_internet_password();
 170         /* otherwise, ignore unknown action */
 171
 172         return 0;
 173 }