Andrew's git / gitweb.git / credential.c
?
credential.con commit Tests: clean up and document submodule helpers (d3b5a49)
   1#include "cache.h"
   2#include "config.h"
   3#include "credential.h"
   4#include "string-list.h"
   5#include "run-command.h"
   6#include "url.h"
   7#include "prompt.h"
   8
   9void credential_init(struct credential *c)
  10{
  11        memset(c, 0, sizeof(*c));
  12        c->helpers.strdup_strings = 1;
  13}
  14
  15void credential_clear(struct credential *c)
  16{
  17        free(c->protocol);
  18        free(c->host);
  19        free(c->path);
  20        free(c->username);
  21        free(c->password);
  22        string_list_clear(&c->helpers, 0);
  23
  24        credential_init(c);
  25}
  26
  27int credential_match(const struct credential *want,
  28                     const struct credential *have)
  29{
  30#define CHECK(x) (!want->x || (have->x && !strcmp(want->x, have->x)))
  31        return CHECK(protocol) &&
  32               CHECK(host) &&
  33               CHECK(path) &&
  34               CHECK(username);
  35#undef CHECK
  36}
  37
  38static int credential_config_callback(const char *var, const char *value,
  39                                      void *data)
  40{
  41        struct credential *c = data;
  42        const char *key, *dot;
  43
  44        if (!skip_prefix(var, "credential.", &key))
  45                return 0;
  46
  47        if (!value)
  48                return config_error_nonbool(var);
  49
  50        dot = strrchr(key, '.');
  51        if (dot) {
  52                struct credential want = CREDENTIAL_INIT;
  53                char *url = xmemdupz(key, dot - key);
  54                int matched;
  55
  56                credential_from_url(&want, url);
  57                matched = credential_match(&want, c);
  58
  59                credential_clear(&want);
  60                free(url);
  61
  62                if (!matched)
  63                        return 0;
  64                key = dot + 1;
  65        }
  66
  67        if (!strcmp(key, "helper")) {
  68                if (*value)
  69                        string_list_append(&c->helpers, value);
  70                else
  71                        string_list_clear(&c->helpers, 0);
  72        } else if (!strcmp(key, "username")) {
  73                if (!c->username)
  74                        c->username = xstrdup(value);
  75        }
  76        else if (!strcmp(key, "usehttppath"))
  77                c->use_http_path = git_config_bool(var, value);
  78
  79        return 0;
  80}
  81
  82static int proto_is_http(const char *s)
  83{
  84        if (!s)
  85                return 0;
  86        return !strcmp(s, "https") || !strcmp(s, "http");
  87}
  88
  89static void credential_apply_config(struct credential *c)
  90{
  91        if (c->configured)
  92                return;
  93        git_config(credential_config_callback, c);
  94        c->configured = 1;
  95
  96        if (!c->use_http_path && proto_is_http(c->protocol)) {
  97                FREE_AND_NULL(c->path);
  98        }
  99}
 100
 101static void credential_describe(struct credential *c, struct strbuf *out)
 102{
 103        if (!c->protocol)
 104                return;
 105        strbuf_addf(out, "%s://", c->protocol);
 106        if (c->username && *c->username)
 107                strbuf_addf(out, "%s@", c->username);
 108        if (c->host)
 109                strbuf_addstr(out, c->host);
 110        if (c->path)
 111                strbuf_addf(out, "/%s", c->path);
 112}
 113
 114static char *credential_ask_one(const char *what, struct credential *c,
 115                                int flags)
 116{
 117        struct strbuf desc = STRBUF_INIT;
 118        struct strbuf prompt = STRBUF_INIT;
 119        char *r;
 120
 121        credential_describe(c, &desc);
 122        if (desc.len)
 123                strbuf_addf(&prompt, "%s for '%s': ", what, desc.buf);
 124        else
 125                strbuf_addf(&prompt, "%s: ", what);
 126
 127        r = git_prompt(prompt.buf, flags);
 128
 129        strbuf_release(&desc);
 130        strbuf_release(&prompt);
 131        return xstrdup(r);
 132}
 133
 134static void credential_getpass(struct credential *c)
 135{
 136        if (!c->username)
 137                c->username = credential_ask_one("Username", c,
 138                                                 PROMPT_ASKPASS|PROMPT_ECHO);
 139        if (!c->password)
 140                c->password = credential_ask_one("Password", c,
 141                                                 PROMPT_ASKPASS);
 142}
 143
 144int credential_read(struct credential *c, FILE *fp)
 145{
 146        struct strbuf line = STRBUF_INIT;
 147
 148        while (strbuf_getline_lf(&line, fp) != EOF) {
 149                char *key = line.buf;
 150                char *value = strchr(key, '=');
 151
 152                if (!line.len)
 153                        break;
 154
 155                if (!value) {
 156                        warning("invalid credential line: %s", key);
 157                        strbuf_release(&line);
 158                        return -1;
 159                }
 160                *value++ = '\0';
 161
 162                if (!strcmp(key, "username")) {
 163                        free(c->username);
 164                        c->username = xstrdup(value);
 165                } else if (!strcmp(key, "password")) {
 166                        free(c->password);
 167                        c->password = xstrdup(value);
 168                } else if (!strcmp(key, "protocol")) {
 169                        free(c->protocol);
 170                        c->protocol = xstrdup(value);
 171                } else if (!strcmp(key, "host")) {
 172                        free(c->host);
 173                        c->host = xstrdup(value);
 174                } else if (!strcmp(key, "path")) {
 175                        free(c->path);
 176                        c->path = xstrdup(value);
 177                } else if (!strcmp(key, "url")) {
 178                        credential_from_url(c, value);
 179                } else if (!strcmp(key, "quit")) {
 180                        c->quit = !!git_config_bool("quit", value);
 181                }
 182                /*
 183                 * Ignore other lines; we don't know what they mean, but
 184                 * this future-proofs us when later versions of git do
 185                 * learn new lines, and the helpers are updated to match.
 186                 */
 187        }
 188
 189        strbuf_release(&line);
 190        return 0;
 191}
 192
 193static void credential_write_item(FILE *fp, const char *key, const char *value)
 194{
 195        if (!value)
 196                return;
 197        fprintf(fp, "%s=%s\n", key, value);
 198}
 199
 200void credential_write(const struct credential *c, FILE *fp)
 201{
 202        credential_write_item(fp, "protocol", c->protocol);
 203        credential_write_item(fp, "host", c->host);
 204        credential_write_item(fp, "path", c->path);
 205        credential_write_item(fp, "username", c->username);
 206        credential_write_item(fp, "password", c->password);
 207}
 208
 209static int run_credential_helper(struct credential *c,
 210                                 const char *cmd,
 211                                 int want_output)
 212{
 213        struct child_process helper = CHILD_PROCESS_INIT;
 214        const char *argv[] = { NULL, NULL };
 215        FILE *fp;
 216
 217        argv[0] = cmd;
 218        helper.argv = argv;
 219        helper.use_shell = 1;
 220        helper.in = -1;
 221        if (want_output)
 222                helper.out = -1;
 223        else
 224                helper.no_stdout = 1;
 225
 226        if (start_command(&helper) < 0)
 227                return -1;
 228
 229        fp = xfdopen(helper.in, "w");
 230        credential_write(c, fp);
 231        fclose(fp);
 232
 233        if (want_output) {
 234                int r;
 235                fp = xfdopen(helper.out, "r");
 236                r = credential_read(c, fp);
 237                fclose(fp);
 238                if (r < 0) {
 239                        finish_command(&helper);
 240                        return -1;
 241                }
 242        }
 243
 244        if (finish_command(&helper))
 245                return -1;
 246        return 0;
 247}
 248
 249static int credential_do(struct credential *c, const char *helper,
 250                         const char *operation)
 251{
 252        struct strbuf cmd = STRBUF_INIT;
 253        int r;
 254
 255        if (helper[0] == '!')
 256                strbuf_addstr(&cmd, helper + 1);
 257        else if (is_absolute_path(helper))
 258                strbuf_addstr(&cmd, helper);
 259        else
 260                strbuf_addf(&cmd, "git credential-%s", helper);
 261
 262        strbuf_addf(&cmd, " %s", operation);
 263        r = run_credential_helper(c, cmd.buf, !strcmp(operation, "get"));
 264
 265        strbuf_release(&cmd);
 266        return r;
 267}
 268
 269void credential_fill(struct credential *c)
 270{
 271        int i;
 272
 273        if (c->username && c->password)
 274                return;
 275
 276        credential_apply_config(c);
 277
 278        for (i = 0; i < c->helpers.nr; i++) {
 279                credential_do(c, c->helpers.items[i].string, "get");
 280                if (c->username && c->password)
 281                        return;
 282                if (c->quit)
 283                        die("credential helper '%s' told us to quit",
 284                            c->helpers.items[i].string);
 285        }
 286
 287        credential_getpass(c);
 288        if (!c->username && !c->password)
 289                die("unable to get password from user");
 290}
 291
 292void credential_approve(struct credential *c)
 293{
 294        int i;
 295
 296        if (c->approved)
 297                return;
 298        if (!c->username || !c->password)
 299                return;
 300
 301        credential_apply_config(c);
 302
 303        for (i = 0; i < c->helpers.nr; i++)
 304                credential_do(c, c->helpers.items[i].string, "store");
 305        c->approved = 1;
 306}
 307
 308void credential_reject(struct credential *c)
 309{
 310        int i;
 311
 312        credential_apply_config(c);
 313
 314        for (i = 0; i < c->helpers.nr; i++)
 315                credential_do(c, c->helpers.items[i].string, "erase");
 316
 317        FREE_AND_NULL(c->username);
 318        FREE_AND_NULL(c->password);
 319        c->approved = 0;
 320}
 321
 322void credential_from_url(struct credential *c, const char *url)
 323{
 324        const char *at, *colon, *cp, *slash, *host, *proto_end;
 325
 326        credential_clear(c);
 327
 328        /*
 329         * Match one of:
 330         *   (1) proto://<host>/...
 331         *   (2) proto://<user>@<host>/...
 332         *   (3) proto://<user>:<pass>@<host>/...
 333         */
 334        proto_end = strstr(url, "://");
 335        if (!proto_end)
 336                return;
 337        cp = proto_end + 3;
 338        at = strchr(cp, '@');
 339        colon = strchr(cp, ':');
 340        slash = strchrnul(cp, '/');
 341
 342        if (!at || slash <= at) {
 343                /* Case (1) */
 344                host = cp;
 345        }
 346        else if (!colon || at <= colon) {
 347                /* Case (2) */
 348                c->username = url_decode_mem(cp, at - cp);
 349                host = at + 1;
 350        } else {
 351                /* Case (3) */
 352                c->username = url_decode_mem(cp, colon - cp);
 353                c->password = url_decode_mem(colon + 1, at - (colon + 1));
 354                host = at + 1;
 355        }
 356
 357        if (proto_end - url > 0)
 358                c->protocol = xmemdupz(url, proto_end - url);
 359        if (slash - host > 0)
 360                c->host = url_decode_mem(host, slash - host);
 361        /* Trim leading and trailing slashes from path */
 362        while (*slash == '/')
 363                slash++;
 364        if (*slash) {
 365                char *p;
 366                c->path = url_decode(slash);
 367                p = c->path + strlen(c->path) - 1;
 368                while (p > c->path && *p == '/')
 369                        *p-- = '\0';
 370        }
 371}