FilesExpand file tree

 master

/

credential-cache--daemon.c

Copy path

Blame

More file actions

Blame

More file actions

Latest commit

 

History

History

History

284 lines (242 loc) · 6.29 KB

 master

/

credential-cache--daemon.c

Copy path

Top

File metadata and controls

• Code
• Blame

284 lines (242 loc) · 6.29 KB

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

67

68

69

70

71

72

73

74

75

76

77

78

79

80

81

82

83

84

85

86

87

88

89

90

91

92

93

94

95

96

97

98

99

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

202

203

204

205

206

207

208

209

210

211

212

213

214

215

216

217

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

233

234

235

236

237

238

239

240

241

242

243

244

245

246

247

248

249

250

251

252

253

254

255

256

257

258

259

260

261

262

263

264

265

266

267

268

269

270

271

272

273

274

275

276

277

278

279

280

281

282

283

284

#include "cache.h"

#include "credential.h"

#include "unix-socket.h"

#include "sigchain.h"

#include "parse-options.h"

static const char *socket_path;

static void cleanup_socket(void)

{

if (socket_path)

unlink(socket_path);

}

static void cleanup_socket_on_signal(int sig)

{

cleanup_socket();

sigchain_pop(sig);

raise(sig);

}

struct credential_cache_entry {

struct credential item;

unsigned long expiration;

};

static struct credential_cache_entry *entries;

static int entries_nr;

static int entries_alloc;

static void cache_credential(struct credential *c, int timeout)

{

struct credential_cache_entry *e;

ALLOC_GROW(entries, entries_nr + 1, entries_alloc);

e = &entries[entries_nr++];

/* take ownership of pointers */

memcpy(&e->item, c, sizeof(*c));

memset(c, 0, sizeof(*c));

e->expiration = time(NULL) + timeout;

}

static struct credential_cache_entry *lookup_credential(const struct credential *c)

{

int i;

for (i = 0; i < entries_nr; i++) {

struct credential *e = &entries[i].item;

if (credential_match(c, e))

return &entries[i];

}

return NULL;

}

static void remove_credential(const struct credential *c)

{

struct credential_cache_entry *e;

e = lookup_credential(c);

if (e)

e->expiration = 0;

}

static int check_expirations(void)

{

static unsigned long wait_for_entry_until;

int i = 0;

unsigned long now = time(NULL);

unsigned long next = (unsigned long)-1;

/*

* Initially give the client 30 seconds to actually contact us

* and store a credential before we decide there's no point in

* keeping the daemon around.

*/

if (!wait_for_entry_until)

wait_for_entry_until = now + 30;

while (i < entries_nr) {

if (entries[i].expiration <= now) {

entries_nr--;

credential_clear(&entries[i].item);

if (i != entries_nr)

memcpy(&entries[i], &entries[entries_nr], sizeof(*entries));

/*

* Stick around 30 seconds in case a new credential

* shows up (e.g., because we just removed a failed

* one, and we will soon get the correct one).

*/

wait_for_entry_until = now + 30;

}

else {

if (entries[i].expiration < next)

next = entries[i].expiration;

i++;

}

}

if (!entries_nr) {

if (wait_for_entry_until <= now)

return 0;

next = wait_for_entry_until;

}

return next - now;

}

static int read_request(FILE *fh, struct credential *c,

struct strbuf *action, int *timeout) {

static struct strbuf item = STRBUF_INIT;

const char *p;

strbuf_getline(&item, fh, '\n');

if (!skip_prefix(item.buf, "action=", &p))

return error("client sent bogus action line: %s", item.buf);

strbuf_addstr(action, p);

strbuf_getline(&item, fh, '\n');

if (!skip_prefix(item.buf, "timeout=", &p))

return error("client sent bogus timeout line: %s", item.buf);

*timeout = atoi(p);

if (credential_read(c, fh) < 0)

return -1;

return 0;

}

static void serve_one_client(FILE *in, FILE *out)

{

struct credential c = CREDENTIAL_INIT;

struct strbuf action = STRBUF_INIT;

int timeout = -1;

if (read_request(in, &c, &action, &timeout) < 0)

/* ignore error */ ;

else if (!strcmp(action.buf, "get")) {

struct credential_cache_entry *e = lookup_credential(&c);

if (e) {

fprintf(out, "username=%s\n", e->item.username);

fprintf(out, "password=%s\n", e->item.password);

}

}

else if (!strcmp(action.buf, "exit"))

exit(0);

else if (!strcmp(action.buf, "erase"))

remove_credential(&c);

else if (!strcmp(action.buf, "store")) {

if (timeout < 0)

warning("cache client didn't specify a timeout");

else if (!c.username || !c.password)

warning("cache client gave us a partial credential");

else {

remove_credential(&c);

cache_credential(&c, timeout);

}

}

else

warning("cache client sent unknown action: %s", action.buf);

credential_clear(&c);

strbuf_release(&action);

}

static int serve_cache_loop(int fd)

{

struct pollfd pfd;

unsigned long wakeup;

wakeup = check_expirations();

if (!wakeup)

return 0;

pfd.fd = fd;

pfd.events = POLLIN;

if (poll(&pfd, 1, 1000 * wakeup) < 0) {

if (errno != EINTR)

die_errno("poll failed");

return 1;

}

if (pfd.revents & POLLIN) {

int client, client2;

FILE *in, *out;

client = accept(fd, NULL, NULL);

if (client < 0) {

warning("accept failed: %s", strerror(errno));

return 1;

}

client2 = dup(client);

if (client2 < 0) {

warning("dup failed: %s", strerror(errno));

close(client);

return 1;

}

in = xfdopen(client, "r");

out = xfdopen(client2, "w");

serve_one_client(in, out);

fclose(in);

fclose(out);

}

return 1;

}

static void serve_cache(const char *socket_path, int debug)

{

int fd;

fd = unix_stream_listen(socket_path);

if (fd < 0)

die_errno("unable to bind to '%s'", socket_path);

printf("ok\n");

fclose(stdout);

if (!debug) {

if (!freopen("/dev/null", "w", stderr))

die_errno("unable to point stderr to /dev/null");

}

while (serve_cache_loop(fd))

; /* nothing */

close(fd);

unlink(socket_path);

}

static const char permissions_advice[] =

"The permissions on your socket directory are too loose; other\n"

"users may be able to read your cached credentials. Consider running:\n"

"\n"

" chmod 0700 %s";

static void check_socket_directory(const char *path)

{

struct stat st;

char *path_copy = xstrdup(path);

char *dir = dirname(path_copy);

if (!stat(dir, &st)) {

if (st.st_mode & 077)

die(permissions_advice, dir);

free(path_copy);

return;

}

/*

* We must be sure to create the directory with the correct mode,

* not just chmod it after the fact; otherwise, there is a race

* condition in which somebody can chdir to it, sleep, then try to open

* our protected socket.

*/

if (safe_create_leading_directories_const(dir) < 0)

die_errno("unable to create directories for '%s'", dir);

if (mkdir(dir, 0700) < 0)

die_errno("unable to mkdir '%s'", dir);

free(path_copy);

}

int main(int argc, const char **argv)

{

static const char *usage[] = {

"git-credential-cache--daemon [opts] <socket_path>",

NULL

};

int debug = 0;

const struct option options[] = {

OPT_BOOL(0, "debug", &debug,

N_("print debugging messages to stderr")),

OPT_END()

};

argc = parse_options(argc, argv, NULL, options, usage, 0);

socket_path = argv[0];

if (!socket_path)

usage_with_options(usage, options);

check_socket_directory(socket_path);

atexit(cleanup_socket);

sigchain_push_common(cleanup_socket_on_signal);

serve_cache(socket_path, debug);

return 0;

}