diff options
| -rw-r--r-- | include/libbb.h | 1 | ||||
| -rw-r--r-- | networking/ftpgetput.c | 57 | ||||
| -rw-r--r-- | networking/parse_pasv_epsv.c | 66 | ||||
| -rw-r--r-- | networking/wget.c | 19 |
4 files changed, 82 insertions, 61 deletions
diff --git a/include/libbb.h b/include/libbb.h index a4eb6ee..e2bedaf 100644 --- a/include/libbb.h +++ b/include/libbb.h @@ -787,6 +787,7 @@ ssize_t recv_from_to(int fd, void *buf, size_t len, int flags, socklen_t sa_size) FAST_FUNC; uint16_t inet_cksum(uint16_t *addr, int len) FAST_FUNC; +int parse_pasv_epsv(char *buf) FAST_FUNC; /* 0 if argv[0] is NULL: */ unsigned string_array_len(char **argv) FAST_FUNC; diff --git a/networking/ftpgetput.c b/networking/ftpgetput.c index 697955e..cdad629 100644 --- a/networking/ftpgetput.c +++ b/networking/ftpgetput.c @@ -152,57 +152,16 @@ static void ftp_login(void) static int xconnect_ftpdata(void) { - char *buf_ptr; - unsigned port_num; + int port_num; -/* -PASV command will not work for IPv6. RFC2428 describes -IPv6-capable "extended PASV" - EPSV. - -"EPSV [protocol]" asks server to bind to and listen on a data port -in specified protocol. Protocol is 1 for IPv4, 2 for IPv6. -If not specified, defaults to "same as used for control connection". -If server understood you, it should answer "229 <some text>(|||port|)" -where "|" are literal pipe chars and "port" is ASCII decimal port#. - -There is also an IPv6-capable replacement for PORT (EPRT), -but we don't need that. - -NB: PASV may still work for some servers even over IPv6. -For example, vsftp happily answers -"227 Entering Passive Mode (0,0,0,0,n,n)" and proceeds as usual. -*/ - if (!ENABLE_FEATURE_IPV6 - || ftpcmd("EPSV", NULL) != 229 - ) { -/* maybe also go straight to PAST if lsa->u.sa.sa_family == AF_INET? */ - if (ftpcmd("PASV", NULL) != 227) { - ftp_die("PASV"); - } - - /* Response is "NNN garbageN1,N2,N3,N4,P1,P2[)garbage]" - * Server's IP is N1.N2.N3.N4 (we ignore it) - * Server's port for data connection is P1*256+P2 */ - buf_ptr = strrchr(buf, ')'); - if (buf_ptr) *buf_ptr = '\0'; - - buf_ptr = strrchr(buf, ','); - *buf_ptr = '\0'; - port_num = xatoul_range(buf_ptr + 1, 0, 255); - - buf_ptr = strrchr(buf, ','); - *buf_ptr = '\0'; - port_num += xatoul_range(buf_ptr + 1, 0, 255) * 256; - } else { - /* Response is "NNN garbage(|||P1|)" - * Server's port for data connection is P1 */ - buf_ptr = strrchr(buf, '|'); - if (buf_ptr) *buf_ptr = '\0'; - - buf_ptr = strrchr(buf, '|'); - *buf_ptr = '\0'; - port_num = xatoul_range(buf_ptr + 1, 0, 65535); + if (ENABLE_FEATURE_IPV6 && ftpcmd("EPSV", NULL) == 229) { + /* good */ + } else if (ftpcmd("PASV", NULL) != 227) { + ftp_die("PASV"); } + port_num = parse_pasv_epsv(buf); + if (port_num < 0) + ftp_die("PASV"); set_nport(&lsa->u.sa, htons(port_num)); return xconnect_stream(lsa); diff --git a/networking/parse_pasv_epsv.c b/networking/parse_pasv_epsv.c new file mode 100644 index 0000000..f320871 --- /dev/null +++ b/networking/parse_pasv_epsv.c @@ -0,0 +1,66 @@ +/* + * Utility routines. + * + * Copyright (C) 2018 Denys Vlasenko + * + * Licensed under GPLv2 or later, see file LICENSE in this source tree. + */ +//kbuild:lib-$(CONFIG_FTPGET) += ftpgetput.o +//kbuild:lib-$(CONFIG_FTPPUT) += ftpgetput.o +//kbuild:lib-$(CONFIG_WGET) += parse_pasv_epsv.o + +#include "libbb.h" + +int FAST_FUNC parse_pasv_epsv(char *buf) +{ +/* + * PASV command will not work for IPv6. RFC2428 describes + * IPv6-capable "extended PASV" - EPSV. + * + * "EPSV [protocol]" asks server to bind to and listen on a data port + * in specified protocol. Protocol is 1 for IPv4, 2 for IPv6. + * If not specified, defaults to "same as used for control connection". + * If server understood you, it should answer "229 <some text>(|||port|)" + * where "|" are literal pipe chars and "port" is ASCII decimal port#. + * + * There is also an IPv6-capable replacement for PORT (EPRT), + * but we don't need that. + * + * NB: PASV may still work for some servers even over IPv6. + * For example, vsftp happily answers + * "227 Entering Passive Mode (0,0,0,0,n,n)" and proceeds as usual. + */ + char *ptr; + int port; + + if (!ENABLE_FEATURE_IPV6 || buf[2] == '7' /* "227" */) { + /* Response is "227 garbageN1,N2,N3,N4,P1,P2[)garbage]" + * Server's IP is N1.N2.N3.N4 (we ignore it) + * Server's port for data connection is P1*256+P2 */ + ptr = strrchr(buf, ')'); + if (ptr) *ptr = '\0'; + + ptr = strrchr(buf, ','); + if (!ptr) return -1; + *ptr = '\0'; + port = xatou_range(ptr + 1, 0, 255); + + ptr = strrchr(buf, ','); + if (!ptr) return -1; + *ptr = '\0'; + port += xatou_range(ptr + 1, 0, 255) * 256; + } else { + /* Response is "229 garbage(|||P1|)" + * Server's port for data connection is P1 */ + ptr = strrchr(buf, '|'); + if (!ptr) return -1; + *ptr = '\0'; + + ptr = strrchr(buf, '|'); + if (!ptr) return -1; + *ptr = '\0'; + port = xatou_range(ptr + 1, 0, 65535); + } + + return port; +} diff --git a/networking/wget.c b/networking/wget.c index daa728a..7ca4bfb 100644 --- a/networking/wget.c +++ b/networking/wget.c @@ -791,22 +791,17 @@ static FILE* prepare_ftp_session(FILE **dfpp, struct host_info *target, len_and_ /* * Entering passive mode */ + if (ENABLE_FEATURE_IPV6 && ftpcmd("EPSV", NULL, sfp) == 229) { + /* good */ + } else if (ftpcmd("PASV", NULL, sfp) != 227) { pasv_error: bb_error_msg_and_die("bad response to %s: %s", "PASV", sanitize_string(G.wget_buf)); } - // Response is "227 garbageN1,N2,N3,N4,P1,P2[)garbage] - // Server's IP is N1.N2.N3.N4 (we ignore it) - // Server's port for data connection is P1*256+P2 - str = strrchr(G.wget_buf, ')'); - if (str) str[0] = '\0'; - str = strrchr(G.wget_buf, ','); - if (!str) goto pasv_error; - port = xatou_range(str+1, 0, 255); - *str = '\0'; - str = strrchr(G.wget_buf, ','); - if (!str) goto pasv_error; - port += xatou_range(str+1, 0, 255) * 256; + port = parse_pasv_epsv(G.wget_buf); + if (port < 0) + goto pasv_error; + set_nport(&lsa->u.sa, htons(port)); *dfpp = open_socket(lsa); |