From ad117d8a213979fae1bf6ec9162c2e998800b096 Mon Sep 17 00:00:00 2001 From: Glenn L McGrath Date: Fri, 5 Oct 2001 04:40:37 +0000 Subject: Apply Magnus Damm's patch, adds tftp blocksize support, and some cleanups. --- networking/tftp.c | 293 ++++++++++++++++++++++++++++++++++++++++++++---------- 1 file changed, 242 insertions(+), 51 deletions(-) (limited to 'networking') diff --git a/networking/tftp.c b/networking/tftp.c index 999b5d706..530b3d134 100644 --- a/networking/tftp.c +++ b/networking/tftp.c @@ -3,7 +3,8 @@ /* */ /* A simple tftp client for busybox. */ /* Tries to follow RFC1350. */ -/* Only "octet" mode and 512-byte data blocks are supported. */ +/* Only "octet" mode supported. */ +/* Optional blocksize negotiation (RFC2347 + RFC2348) */ /* */ /* Copyright (C) 2001 Magnus Damm */ /* */ @@ -47,6 +48,18 @@ //#define BB_FEATURE_TFTP_DEBUG +#define TFTP_BLOCKSIZE_DEFAULT 512 /* according to RFC 1350, don't change */ +#define TFTP_TIMEOUT 5 /* seconds */ + +/* opcodes we support */ + +#define TFTP_RRQ 1 +#define TFTP_WRQ 2 +#define TFTP_DATA 3 +#define TFTP_ACK 4 +#define TFTP_ERROR 5 +#define TFTP_OACK 6 + static const char *tftp_error_msg[] = { "Undefined error", "File not found", @@ -61,8 +74,71 @@ static const char *tftp_error_msg[] = { const int tftp_cmd_get = 1; const int tftp_cmd_put = 2; +#ifdef BB_FEATURE_TFTP_BLOCKSIZE + +static int tftp_blocksize_check(int blocksize, int bufsize) +{ + /* Check if the blocksize is valid: + * RFC2348 says between 8 and 65464, + * but our implementation makes it impossible + * to use blocksizes smaller than 22 octets. + */ + + if ((bufsize && (blocksize > bufsize)) || + (blocksize < 8) || (blocksize > 65464)) { + error_msg("bad blocksize"); + return 0; + } + + return blocksize; +} + +static char *tftp_option_get(char *buf, int len, char *option) +{ + int opt_val = 0; + int opt_found = 0; + int k; + + while (len > 0) { + + /* Make sure the options are terminated correctly */ + + for (k = 0; k < len; k++) { + if (buf[k] == '\0') { + break; + } + } + + if (k >= len) { + break; + } + + if (opt_val == 0) { + if (strcasecmp(buf, option) == 0) { + opt_found = 1; + } + } + else { + if (opt_found) { + return buf; + } + } + + k++; + + buf += k; + len -= k; + + opt_val ^= 1; + } + + return NULL; +} + +#endif + static inline int tftp(const int cmd, const struct hostent *host, - const char *serverfile, int localfd, const int port, int tftp_bufsize) + const char *remotefile, int localfd, const int port, int tftp_bufsize) { const int cmd_get = cmd & tftp_cmd_get; const int cmd_put = cmd & tftp_cmd_put; @@ -81,7 +157,12 @@ static inline int tftp(const int cmd, const struct hostent *host, int finished = 0; int timeout = bb_tftp_num_retries; int block_nr = 1; - RESERVE_BB_BUFFER(buf, tftp_bufsize + 4); // Why 4 ? + +#ifdef BB_FEATURE_TFTP_BLOCKSIZE + int want_option_ack = 0; +#endif + + RESERVE_BB_BUFFER(buf, tftp_bufsize + 4); /* Opcode + Block # + Data */ tftp_bufsize += 4; @@ -103,50 +184,79 @@ static inline int tftp(const int cmd, const struct hostent *host, /* build opcode */ if (cmd_get) { - opcode = 1; // read request = 1 + opcode = TFTP_RRQ; } if (cmd_put) { - opcode = 2; // write request = 2 + opcode = TFTP_WRQ; } while (1) { - - /* build packet of type "opcode" */ - - cp = buf; + /* first create the opcode part */ + *((unsigned short *) cp) = htons(opcode); cp += 2; /* add filename and mode */ - if ((cmd_get && (opcode == 1)) || // read request = 1 - (cmd_put && (opcode == 2))) { // write request = 2 + if ((cmd_get && (opcode == TFTP_RRQ)) || + (cmd_put && (opcode == TFTP_WRQ))) { + int too_long = 0; - /* what is this trying to do ? */ - while (cp != &buf[tftp_bufsize - 1]) { - if ((*cp = *serverfile++) == '\0') - break; - cp++; + /* see if the filename fits into buf */ + /* and fill in packet */ + + len = strlen(remotefile) + 1; + + if ((cp + len) >= &buf[tftp_bufsize - 1]) { + too_long = 1; } - /* and this ? */ - if ((*cp != '\0') || (&buf[tftp_bufsize - 1] - cp) < 7) { - error_msg("too long server-filename"); + else { + safe_strncpy(cp, remotefile, len); + cp += len; + } + + if (too_long || ((&buf[tftp_bufsize - 1] - cp) < 6)) { + error_msg("too long remote-filename"); break; } - memcpy(cp + 1, "octet", 6); - cp += 7; + /* add "mode" part of the package */ + + memcpy(cp, "octet", 6); + cp += 6; + +#ifdef BB_FEATURE_TFTP_BLOCKSIZE + + len = tftp_bufsize - 4; /* data block size */ + + if (len != TFTP_BLOCKSIZE_DEFAULT) { + + if ((&buf[tftp_bufsize - 1] - cp) < 15) { + error_msg("too long remote-filename"); + break; + } + + /* add "blksize" + number of blocks */ + + memcpy(cp, "blksize", 8); + cp += 8; + + cp += snprintf(cp, 6, "%d", len) + 1; + + want_option_ack = 1; + } +#endif } /* add ack and data */ - if ((cmd_get && (opcode == 4)) || // acknowledgement = 4 - (cmd_put && (opcode == 3))) { // data packet == 3 + if ((cmd_get && (opcode == TFTP_ACK)) || + (cmd_put && (opcode == TFTP_DATA))) { *((unsigned short *) cp) = htons(block_nr); @@ -154,7 +264,7 @@ static inline int tftp(const int cmd, const struct hostent *host, block_nr++; - if (cmd_put && (opcode == 3)) { // data packet == 3 + if (cmd_put && (opcode == TFTP_DATA)) { len = read(localfd, cp, tftp_bufsize - 4); if (len < 0) { @@ -200,7 +310,7 @@ static inline int tftp(const int cmd, const struct hostent *host, memset(&from, 0, sizeof(from)); fromlen = sizeof(from); - tv.tv_sec = 5; // BB_TFPT_TIMEOUT = 5 + tv.tv_sec = TFTP_TIMEOUT; tv.tv_usec = 0; FD_ZERO(&rfds); @@ -261,9 +371,76 @@ static inline int tftp(const int cmd, const struct hostent *host, printf("received %d bytes: %04x %04x\n", len, opcode, tmp); #endif - if (cmd_get && (opcode == 3)) { // data packet == 3 + if (opcode == TFTP_ERROR) { + char *msg = NULL; + + if (buf[4] != '\0') { + msg = &buf[4]; + buf[tftp_bufsize - 1] = '\0'; + } else if (tmp < (sizeof(tftp_error_msg) + / sizeof(char *))) { + + msg = (char *) tftp_error_msg[tmp]; + } + + if (msg) { + error_msg("server says: %s", msg); + } + + break; + } + +#ifdef BB_FEATURE_TFTP_BLOCKSIZE + if (want_option_ack) { + + want_option_ack = 0; + + if (opcode == TFTP_OACK) { + + /* server seems to support options */ + + char *res; + + res = tftp_option_get(&buf[2], len-2, + "blksize"); + + if (res) { + int foo = atoi(res); + + if (tftp_blocksize_check(foo, + tftp_bufsize - 4)) { + + if (cmd_put) { + opcode = TFTP_DATA; + } + else { + opcode = TFTP_ACK; + } +#ifdef BB_FEATURE_TFTP_DEBUG + printf("using blksize %u\n"); +#endif + tftp_bufsize = foo + 4; + block_nr = 0; + continue; + } + } + /* FIXME: + * we should send ERROR 8 */ + error_msg("bad server option"); + break; + } + + error_msg("warning: blksize not supported by server" + " - reverting to 512"); + + tftp_bufsize = TFTP_BLOCKSIZE_DEFAULT + 4; + } +#endif + + if (cmd_get && (opcode == TFTP_DATA)) { if (tmp == block_nr) { + len = write(localfd, &buf[4], len - 4); if (len < 0) { @@ -275,43 +452,30 @@ static inline int tftp(const int cmd, const struct hostent *host, finished++; } - opcode = 4; // acknowledgement = 4 + opcode = TFTP_ACK; continue; } } - if (cmd_put && (opcode == 4)) { // acknowledgement = 4 + if (cmd_put && (opcode == TFTP_ACK)) { if (tmp == (block_nr - 1)) { if (finished) { break; } - opcode = 3; // data packet == 3 + opcode = TFTP_DATA; continue; } } - - if (opcode == 5) { // error code == 5 - char *msg = NULL; - - if (buf[4] != '\0') { - msg = &buf[4]; - buf[tftp_bufsize - 1] = '\0'; - } else if (tmp < (sizeof(tftp_error_msg) / sizeof(char *))) { - msg = (char *) tftp_error_msg[tmp]; - } - - if (msg) { - error_msg("server says: %s", msg); - } - - break; - } } +#ifdef BB_FEATURE_CLEAN_UP close(socketfd); + RELEASE_BB_BUFFER(buf); +#endif + return finished ? EXIT_SUCCESS : EXIT_FAILURE; } @@ -326,13 +490,38 @@ int tftp_main(int argc, char **argv) int flags = 0; int opt; int result; - int blocksize = 512; + int blocksize = TFTP_BLOCKSIZE_DEFAULT; + + /* figure out what to pass to getopt */ - while ((opt = getopt(argc, argv, "b:gpl:r:")) != -1) { +#ifdef BB_FEATURE_TFTP_BLOCKSIZE +#define BS "b:" +#else +#define BS +#endif + +#ifdef BB_FEATURE_TFTP_GET +#define GET "g" +#else +#define GET +#endif + +#ifdef BB_FEATURE_TFTP_PUT +#define PUT "p" +#else +#define PUT +#endif + + while ((opt = getopt(argc, argv, BS GET PUT "l:r:")) != -1) { switch (opt) { +#ifdef BB_FEATURE_TFTP_BLOCKSIZE case 'b': blocksize = atoi(optarg); + if (!tftp_blocksize_check(blocksize, 0)) { + return EXIT_FAILURE; + } break; +#endif #ifdef BB_FEATURE_TFTP_GET case 'g': cmd = tftp_cmd_get; @@ -370,14 +559,16 @@ int tftp_main(int argc, char **argv) } #ifdef BB_FEATURE_TFTP_DEBUG - printf("using server \"%s\", serverfile \"%s\"," + printf("using server \"%s\", remotefile \"%s\", " "localfile \"%s\".\n", inet_ntoa(*((struct in_addr *) host->h_addr)), remotefile, localfile); #endif result = tftp(cmd, host, remotefile, fd, port, blocksize); - close(fd); +#ifdef BB_FEATURE_CLEAN_UP + close(fd); +#endif return(result); -} \ No newline at end of file +} -- cgit v1.2.3