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403a5a298

Denis Vlasenko
Denis Vlasenko
2008-03-19
FAILED Duration: 20s

Subject

tftpd: options -c (allow _new_ files to be uploaded) and -u USER

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No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

include/usage.h +4 -2networking/tftp.c +84 -63
include/usage.h+4 -2
@@ -3977,11 +3977,13 @@
)
#define tftpd_trivial_usage \
- "[-r] [DIR]"
+ "[-cr] [-u USER] [DIR]"
#define tftpd_full_usage \
- "Transfer a file on request from a tftp client.\n" \
+ "Transfer a file on tftp client's request.\n" \
"\nOptions:" \
"\n -r Prohibit upload" \
+ "\n -c Allow file creation via upload" \
+ "\n -u Access files as USER" \
#define time_trivial_usage \
"[OPTION]... COMMAND [ARGS...]"
networking/tftp.c+84 -63
@@ -51,6 +51,17 @@
#define ERR_BAD_USER 7
#define ERR_BAD_OPT 8
+/* masks coming from getopt32 */
+enum {
+ TFTP_OPT_GET = (1 << 0),
+ TFTP_OPT_PUT = (1 << 1),
+ /* pseudo option: if set, it's tftpd */
+ TFTPD_OPT = (1 << 7) * ENABLE_TFTPD,
+ TFTPD_OPT_r = (1 << 8) * ENABLE_TFTPD,
+ TFTPD_OPT_c = (1 << 9) * ENABLE_TFTPD,
+ TFTPD_OPT_u = (1 << 10) * ENABLE_TFTPD,
+};
+
#if ENABLE_FEATURE_TFTP_GET && !ENABLE_FEATURE_TFTP_PUT
#define USE_GETPUT(...)
#define CMD_GET(cmd) 1
@@ -61,9 +72,8 @@
#define CMD_PUT(cmd) 1
#else
#define USE_GETPUT(...) __VA_ARGS__
-/* masks coming from getopt32 */
-#define CMD_GET(cmd) ((cmd) & 1)
-#define CMD_PUT(cmd) ((cmd) & 2)
+#define CMD_GET(cmd) ((cmd) & TFTP_OPT_GET)
+#define CMD_PUT(cmd) ((cmd) & TFTP_OPT_PUT)
#endif
/* NB: in the code below
* CMD_GET(cmd) and CMD_PUT(cmd) are mutually exclusive
@@ -73,11 +83,15 @@
struct globals {
/* u16 TFTP_ERROR; u16 reason; both network-endian, then error text: */
uint8_t error_pkt[4 + 32];
+#if ENABLE_TFTPD
+ char *user_opt;
+#endif
/* used in tftpd_main(), a bit big for stack: */
char block_buf[TFTP_BLKSIZE_DEFAULT];
};
#define G (*(struct globals*)&bb_common_bufsiz1)
#define block_buf (G.block_buf )
+#define user_opt (G.user_opt )
#define error_pkt (G.error_pkt )
#define INIT_G() \
do { \
@@ -148,11 +162,10 @@ static char *tftp_get_blksize(char *buf, int len)
#endif
static int tftp_protocol(
- USE_GETPUT(int cmd,)
len_and_sockaddr *our_lsa,
len_and_sockaddr *peer_lsa,
+ const char *local_file,
USE_TFTP(const char *remote_file,)
- int local_fd,
int blksize)
{
#if !ENABLE_TFTP
@@ -167,6 +180,7 @@ static int tftp_protocol(
uint16_t opcode;
uint16_t block_nr;
uint16_t recv_blk;
+ int open_mode, local_fd;
int retries, waittime_ms;
int io_bufsize = blksize + 4;
char *cp;
@@ -180,6 +194,39 @@ static int tftp_protocol(
socket_fd = xsocket(peer_lsa->u.sa.sa_family, SOCK_DGRAM, 0);
setsockopt_reuseaddr(socket_fd);
+#if ENABLE_TFTPD
+ if (user_opt) {
+ struct passwd *pw = getpwnam(user_opt); /* initgroups, setgid, setuid */
+ if (!pw)
+ bb_error_msg_and_die("unknown user '%s'", user_opt);
+ change_identity(pw);
+ }
+#endif
+
+ if (CMD_PUT(option_mask32)) {
+ open_mode = O_RDONLY;
+ } else {
+ open_mode = O_WRONLY | O_TRUNC | O_CREAT;
+#if ENABLE_TFTPD
+ if ((option_mask32 & (TFTPD_OPT+TFTPD_OPT_c)) == TFTPD_OPT) {
+ /* tftpd without -c */
+ open_mode = O_WRONLY | O_TRUNC;
+ }
+#endif
+ }
+ if (!(option_mask32 & TFTPD_OPT)) {
+ local_fd = CMD_GET(option_mask32) ? STDOUT_FILENO : STDIN_FILENO;
+ if (NOT_LONE_DASH(local_file))
+ local_fd = xopen(local_file, open_mode);
+ } else {
+ local_fd = open_or_warn(local_file, open_mode);
+ if (local_fd < 0) {
+ /*error_pkt_reason = ERR_NOFILE/ERR_ACCESS?*/
+ strcpy(error_pkt_str, "can't open file");
+ goto send_err_pkt;
+ }
+ }
+
block_nr = 1;
if (!ENABLE_TFTP || our_lsa) {
/* tftpd */
@@ -197,7 +244,7 @@ static int tftp_protocol(
if (error_pkt_reason || error_pkt_str[0])
goto send_err_pkt;
- if (CMD_GET(cmd)) {
+ if (CMD_GET(option_mask32)) {
/* it's upload - we must ACK 1st packet (with filename)
* as if it's "block 0" */
block_nr = 0;
@@ -231,7 +278,7 @@ static int tftp_protocol(
/* build opcode */
opcode = TFTP_WRQ;
- if (CMD_GET(cmd)) {
+ if (CMD_GET(option_mask32)) {
opcode = TFTP_RRQ;
}
cp = xbuf + 2;
@@ -276,7 +323,7 @@ static int tftp_protocol(
cp += 2;
block_nr++;
opcode = TFTP_ACK;
- if (CMD_PUT(cmd)) {
+ if (CMD_PUT(option_mask32)) {
opcode = TFTP_DATA;
len = full_read(local_fd, cp, blksize);
if (len < 0) {
@@ -420,7 +467,7 @@ static int tftp_protocol(
/* block_nr is already advanced to next block# we expect
* to get / block# we are about to send next time */
- if (CMD_GET(cmd) && (opcode == TFTP_DATA)) {
+ if (CMD_GET(option_mask32) && (opcode == TFTP_DATA)) {
if (recv_blk == block_nr) {
int sz = full_write(local_fd, &rbuf[4], len - 4);
if (sz != len - 4) {
@@ -440,7 +487,7 @@ static int tftp_protocol(
}
}
- if (CMD_PUT(cmd) && (opcode == TFTP_ACK)) {
+ if (CMD_PUT(option_mask32) && (opcode == TFTP_ACK)) {
/* did peer ACK our last DATA pkt? */
if (recv_blk == (uint16_t) (block_nr - 1)) {
if (finished)
@@ -462,6 +509,7 @@ static int tftp_protocol(
} /* end of "while (1)" */
ret:
if (ENABLE_FEATURE_CLEAN_UP) {
+ close(local_fd);
close(socket_fd);
free(xbuf);
free(rbuf);
@@ -487,13 +535,11 @@ int tftp_main(int argc ATTRIBUTE_UNUSED, char **argv)
len_and_sockaddr *peer_lsa;
const char *local_file = NULL;
const char *remote_file = NULL;
- int port;
- USE_GETPUT(int cmd;)
- int local_fd;
- int flags = 0;
- int result;
- int blksize;
const char *blksize_str = "512";
+ int blksize;
+ int result;
+ int port;
+ USE_GETPUT(int opt;)
INIT_G();
@@ -501,17 +547,13 @@ int tftp_main(int argc ATTRIBUTE_UNUSED, char **argv)
opt_complementary = "" USE_FEATURE_TFTP_GET("g:") USE_FEATURE_TFTP_PUT("p:")
USE_GETPUT("g--p:p--g:");
- USE_GETPUT(cmd =) getopt32(argv,
+ USE_GETPUT(opt =) getopt32(argv,
USE_FEATURE_TFTP_GET("g") USE_FEATURE_TFTP_PUT("p")
"l:r:" USE_FEATURE_TFTP_BLOCKSIZE("b:"),
&local_file, &remote_file
USE_FEATURE_TFTP_BLOCKSIZE(, &blksize_str));
argv += optind;
- flags = O_RDONLY;
- if (CMD_GET(cmd))
- flags = O_WRONLY | O_CREAT | O_TRUNC;
-
#if ENABLE_FEATURE_TFTP_BLOCKSIZE
/* Check if the blksize is valid:
* RFC2348 says between 8 and 65464 */
@@ -530,11 +572,6 @@ int tftp_main(int argc ATTRIBUTE_UNUSED, char **argv)
if (!remote_file || !argv[0])
bb_show_usage();
- local_fd = CMD_GET(cmd) ? STDOUT_FILENO : STDIN_FILENO;
- if (!LONE_DASH(local_file)) {
- local_fd = xopen(local_file, flags);
- }
-
port = bb_lookup_port(argv[1], "udp", 69);
peer_lsa = xhost2sockaddr(argv[0], port);
@@ -545,14 +582,11 @@ int tftp_main(int argc ATTRIBUTE_UNUSED, char **argv)
#endif
result = tftp_protocol(
- USE_GETPUT(cmd,)
- NULL /* our_lsa*/,
- peer_lsa,
- remote_file, local_fd, blksize);
+ NULL /* our_lsa*/, peer_lsa,
+ local_file, remote_file,
+ blksize);
- if (ENABLE_FEATURE_CLEAN_UP)
- close(local_fd);
- if (result != EXIT_SUCCESS && !LONE_DASH(local_file) && CMD_GET(cmd)) {
+ if (result != EXIT_SUCCESS && NOT_LONE_DASH(local_file) && CMD_GET(opt)) {
unlink(local_file);
}
return result;
@@ -581,9 +615,9 @@ int tftpd_main(int argc ATTRIBUTE_UNUSED, char **argv)
{
len_and_sockaddr *our_lsa;
len_and_sockaddr *peer_lsa;
- char *filename, *mode;
+ char *local_file, *mode;
const char *error_msg;
- int opt_r, result, opcode, open_mode;
+ int opt, result, opcode;
int local_fd = local_fd; /* for compiler */
int blksize = blksize;
USE_GETPUT(int cmd = cmd;)
@@ -596,7 +630,8 @@ int tftpd_main(int argc ATTRIBUTE_UNUSED, char **argv)
peer_lsa = xzalloc(LSA_LEN_SIZE + our_lsa->len);
peer_lsa->len = our_lsa->len;
- opt_r = getopt32(argv, "r");
+ /* Shifting to not collide with TFTP_OPTs */
+ opt = option_mask32 = TFTPD_OPT | (getopt32(argv, "rcu:", &user_opt) << 8);
argv += optind;
if (argv[0])
xchdir(argv[0]);
@@ -616,15 +651,13 @@ int tftpd_main(int argc ATTRIBUTE_UNUSED, char **argv)
) {
goto err;
}
- filename = block_buf + 2;
- if (filename[0] == '.' || strstr(filename, "/.")) {
- error_msg = "dot in filename";
+ local_file = block_buf + 2;
+ if (local_file[0] == '.' || strstr(local_file, "/.")) {
+ error_msg = "dot in local_file";
goto err;
}
- mode = filename + strlen(filename) + 1;
- if (mode >= block_buf + result
- || strcmp(mode, "octet") != 0
- ) {
+ mode = local_file + strlen(local_file) + 1;
+ if (mode >= block_buf + result || strcmp(mode, "octet") != 0) {
goto err;
}
blksize = TFTP_BLKSIZE_DEFAULT;
@@ -647,29 +680,16 @@ int tftpd_main(int argc ATTRIBUTE_UNUSED, char **argv)
}
#endif
-#if ENABLE_FEATURE_TFTP_PUT
- /* in case opcode is TFTP_RRQ: */
- USE_GETPUT(cmd = 2;) /* CMD_PUT: we will send file's data */
- open_mode = O_RDONLY;
-#endif
-#if ENABLE_FEATURE_TFTP_GET
if (!ENABLE_FEATURE_TFTP_PUT || opcode == TFTP_WRQ) {
- if (opt_r) {
+ if (opt & TFTPD_OPT_r) {
/* This would mean "disk full" - not true */
/*error_pkt_reason = ERR_WRITE;*/
error_msg = bb_msg_write_error;
goto err;
}
- USE_GETPUT(cmd = 1;) /* CMD_GET: we will receive file's data */
- open_mode = O_WRONLY | O_TRUNC;
- }
-#endif
- local_fd = open(filename, open_mode);
- if (local_fd < 0) {
- /*error_pkt_reason = ERR_NOFILE/ERR_ACCESS?*/
- error_msg = "can't open file";
- err:
- strcpy(error_pkt_str, error_msg);
+ USE_GETPUT(option_mask32 |= TFTP_OPT_GET;) /* will receive file's data */
+ } else {
+ USE_GETPUT(option_mask32 |= TFTP_OPT_PUT;) /* will send file's data */
}
close(STDIN_FILENO); /* close old, possibly wildcard socket */
@@ -679,14 +699,15 @@ int tftpd_main(int argc ATTRIBUTE_UNUSED, char **argv)
* tftp_protocol() just sends one error pkt and returns */
do_proto:
result = tftp_protocol(
- USE_GETPUT(cmd,)
our_lsa, peer_lsa,
- USE_TFTP(NULL /*remote_file*/,)
- local_fd,
+ local_file, USE_TFTP(NULL /*remote_file*/,)
blksize
);
return result;
+ err:
+ strcpy(error_pkt_str, error_msg);
+ goto do_proto;
}
#endif /* ENABLE_TFTPD */