From 9069c849074bc13dda505d461be97dd6357637aa Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Fri, 12 Dec 2008 07:00:38 -0500 Subject: [PATCH] mount.cifs: allow mounts to ipv6 capable servers The current name resolution scheme in mount.cifs is IPv4 only. Expand it to be protocol-independent. Also take advantage of the fact that getaddrinfo() returns a list of addresses and have mount.cifs try each in turn until it hits one that's reachable and allows the socket to connect. Signed-off-by: Jeff Layton --- source3/client/mount.cifs.c | 221 ++++++++++++++++++++---------------- 1 file changed, 120 insertions(+), 101 deletions(-) diff --git a/source3/client/mount.cifs.c b/source3/client/mount.cifs.c index 0bc61ae38f..9f4d1d3fd0 100644 --- a/source3/client/mount.cifs.c +++ b/source3/client/mount.cifs.c @@ -80,6 +80,9 @@ #define MOUNT_PASSWD_SIZE 64 #define DOMAIN_SIZE 64 +/* currently maximum length of IPv6 address string */ +#define MAX_ADDRESS_LEN INET6_ADDRSTRLEN + const char *thisprogram; int verboseflag = 0; static int got_password = 0; @@ -189,12 +192,6 @@ static char * getusername(void) { return username; } -static char * parse_cifs_url(char * unc_name) -{ - printf("\nMounting cifs URL not implemented yet. Attempt to mount %s\n",unc_name); - return NULL; -} - static int open_cred_file(char * file_name) { char * line_buf; @@ -494,7 +491,7 @@ static int parse_options(char ** optionsp, int * filesys_flags) } else if (strncmp(data, "ip", 2) == 0) { if (!value || !*value) { printf("target ip address argument missing"); - } else if (strnlen(value, 35) < 35) { + } else if (strnlen(value, MAX_ADDRESS_LEN) <= MAX_ADDRESS_LEN) { if(verboseflag) printf("ip address %s override specified\n",value); got_ip = 1; @@ -882,23 +879,23 @@ static void replace_char(char *string, char from, char to, int maxlen) } /* Note that caller frees the returned buffer if necessary */ -static char * parse_server(char ** punc_name) +static struct addrinfo * +parse_server(char ** punc_name) { char * unc_name = *punc_name; int length = strnlen(unc_name, MAX_UNC_LEN); char * share; - char * ipaddress_string = NULL; - struct hostent * host_entry = NULL; - struct in_addr server_ipaddr; + struct addrinfo *addrlist; + int rc; if(length > (MAX_UNC_LEN - 1)) { printf("mount error: UNC name too long"); return NULL; } - if (strncasecmp("cifs://",unc_name,7) == 0) - return parse_cifs_url(unc_name+7); - if (strncasecmp("smb://",unc_name,6) == 0) { - return parse_cifs_url(unc_name+6); + if ((strncasecmp("cifs://", unc_name, 7) == 0) || + (strncasecmp("smb://", unc_name, 6) == 0)) { + printf("\nMounting cifs URL not implemented yet. Attempt to mount %s\n", unc_name); + return NULL; } if(length < 3) { @@ -939,7 +936,12 @@ continue_unc_parsing: *share = 0; /* temporarily terminate the string */ share += 1; if(got_ip == 0) { - host_entry = gethostbyname(unc_name); + rc = getaddrinfo(unc_name, NULL, NULL, &addrlist); + if (rc != 0) { + printf("mount error: could not resolve address for %s: %s\n", + unc_name, gai_strerror(rc)); + addrlist = NULL; + } } *(share - 1) = '/'; /* put delimiter back */ @@ -954,23 +956,9 @@ continue_unc_parsing: printf("ip address specified explicitly\n"); return NULL; } - if(host_entry == NULL) { - printf("mount error: could not find target server. TCP name %s not found\n", unc_name); - return NULL; - } else { - /* BB should we pass an alternate version of the share name as Unicode */ - /* BB what about ipv6? BB */ - /* BB add retries with alternate servers in list */ + /* BB should we pass an alternate version of the share name as Unicode */ - memcpy(&server_ipaddr.s_addr, host_entry->h_addr, 4); - - ipaddress_string = inet_ntoa(server_ipaddr); - if(ipaddress_string == NULL) { - printf("mount error: could not get valid ip address for target server\n"); - return NULL; - } - return ipaddress_string; - } + return addrlist; } else { /* BB add code to find DFS root (send null path on get DFS Referral to specified server here */ printf("Mounting the DFS root for a particular server not implemented yet\n"); @@ -1034,10 +1022,11 @@ int main(int argc, char ** argv) int flags = MS_MANDLOCK; /* no need to set legacy MS_MGC_VAL */ char * orgoptions = NULL; char * share_name = NULL; - char * ipaddr = NULL; + const char * ipaddr = NULL; char * uuid = NULL; char * mountpoint = NULL; char * options = NULL; + char * optionstail; char * resolved_path = NULL; char * temp; char * dev_name; @@ -1050,10 +1039,14 @@ int main(int argc, char ** argv) int optlen = 0; int orgoptlen = 0; size_t options_size = 0; + size_t current_len; int retry = 0; /* set when we have to retry mount with uppercase */ + struct addrinfo *addrhead = NULL, *addr; struct stat statbuf; struct utsname sysinfo; struct mntent mountent; + struct sockaddr_in *addr4; + struct sockaddr_in6 *addr6; FILE * pmntfile; /* setlocale(LC_ALL, ""); @@ -1245,8 +1238,8 @@ int main(int argc, char ** argv) rc = EX_USAGE; goto mount_exit; } - ipaddr = parse_server(&share_name); - if((ipaddr == NULL) && (got_ip == 0)) { + addrhead = addr = parse_server(&share_name); + if((addrhead == NULL) && (got_ip == 0)) { printf("No ip address specified and hostname not found\n"); rc = EX_USAGE; goto mount_exit; @@ -1316,7 +1309,6 @@ int main(int argc, char ** argv) } /* FIXME launch daemon (handles dfs name resolution and credential change) remember to clear parms and overwrite password field before launching */ -mount_retry: if(orgoptions) { optlen = strlen(orgoptions); orgoptlen = optlen; @@ -1331,10 +1323,10 @@ mount_retry: } if(user_name) optlen += strlen(user_name) + 6; - if(ipaddr) - optlen += strlen(ipaddr) + 4; + optlen += MAX_ADDRESS_LEN + 4; if(mountpassword) optlen += strlen(mountpassword) + 6; +mount_retry: SAFE_FREE(options); options_size = optlen + 10 + DOMAIN_SIZE; options = (char *)malloc(options_size /* space for commas in password */ + 8 /* space for domain= , domain name itself was counted as part of the length username string above */); @@ -1344,18 +1336,12 @@ mount_retry: exit(EX_SYSERR); } - options[0] = 0; - strlcpy(options,"unc=",options_size); + strlcpy(options, "unc=", options_size); strlcat(options,share_name,options_size); /* scan backwards and reverse direction of slash */ temp = strrchr(options, '/'); if(temp > options + 6) *temp = '\\'; - if(ipaddr) { - strlcat(options,",ip=",options_size); - strlcat(options,ipaddr,options_size); - } - if(user_name) { /* check for syntax like user=domain\user */ if(got_domain == 0) @@ -1397,11 +1383,42 @@ mount_retry: /* convert all '\\' to '/' in share portion so that /proc/mounts looks pretty */ replace_char(dev_name, '\\', '/', strlen(share_name)); - if(mount(dev_name, mountpoint, "cifs", flags, options)) { - /* remember to kill daemon on error */ + if (!got_ip && addr) { + strlcat(options, ",ip=", options_size); + current_len = strnlen(options, options_size); + optionstail = options + current_len; + switch (addr->ai_addr->sa_family) { + case AF_INET6: + addr6 = (struct sockaddr_in6 *) addr->ai_addr; + ipaddr = inet_ntop(AF_INET6, &addr6->sin6_addr, optionstail, + options_size - current_len); + break; + case AF_INET: + addr4 = (struct sockaddr_in *) addr->ai_addr; + ipaddr = inet_ntop(AF_INET, &addr4->sin_addr, optionstail, + options_size - current_len); + break; + } + + /* if the address looks bogus, try the next one */ + if (!ipaddr) { + addr = addr->ai_next; + if (addr) + goto mount_retry; + rc = EX_SYSERR; + goto mount_exit; + } + } + + if (mount(dev_name, mountpoint, "cifs", flags, options)) { switch (errno) { - case 0: - printf("mount failed but no error number set\n"); + case ECONNREFUSED: + case EHOSTUNREACH: + if (addr) { + addr = addr->ai_next; + if (addr) + goto mount_retry; + } break; case ENODEV: printf("mount error: cifs filesystem not supported by the system\n"); @@ -1416,64 +1433,64 @@ mount_retry: goto mount_retry; } } - default: - printf("mount error %d = %s\n",errno,strerror(errno)); } + printf("mount error(%d): %s\n", errno, strerror(errno)); printf("Refer to the mount.cifs(8) manual page (e.g.man mount.cifs)\n"); rc = EX_FAIL; - } else { - atexit(unlock_mtab); - rc = lock_mtab(); - if (rc) { - printf("cannot lock mtab"); - goto mount_exit; - } - pmntfile = setmntent(MOUNTED, "a+"); - if (!pmntfile) { - printf("could not update mount table\n"); - unlock_mtab(); - rc = EX_FILEIO; - goto mount_exit; - } - mountent.mnt_fsname = dev_name; - mountent.mnt_dir = mountpoint; - mountent.mnt_type = CONST_DISCARD(char *,"cifs"); - mountent.mnt_opts = (char *)malloc(220); - if(mountent.mnt_opts) { - char * mount_user = getusername(); - memset(mountent.mnt_opts,0,200); - if(flags & MS_RDONLY) - strlcat(mountent.mnt_opts,"ro",220); - else - strlcat(mountent.mnt_opts,"rw",220); - if(flags & MS_MANDLOCK) - strlcat(mountent.mnt_opts,",mand",220); - if(flags & MS_NOEXEC) - strlcat(mountent.mnt_opts,",noexec",220); - if(flags & MS_NOSUID) - strlcat(mountent.mnt_opts,",nosuid",220); - if(flags & MS_NODEV) - strlcat(mountent.mnt_opts,",nodev",220); - if(flags & MS_SYNCHRONOUS) - strlcat(mountent.mnt_opts,",sync",220); - if(mount_user) { - if(getuid() != 0) { - strlcat(mountent.mnt_opts, - ",user=", 220); - strlcat(mountent.mnt_opts, - mount_user, 220); - } + goto mount_exit; + } + + atexit(unlock_mtab); + rc = lock_mtab(); + if (rc) { + printf("cannot lock mtab"); + goto mount_exit; + } + pmntfile = setmntent(MOUNTED, "a+"); + if (!pmntfile) { + printf("could not update mount table\n"); + unlock_mtab(); + rc = EX_FILEIO; + goto mount_exit; + } + mountent.mnt_fsname = dev_name; + mountent.mnt_dir = mountpoint; + mountent.mnt_type = CONST_DISCARD(char *,"cifs"); + mountent.mnt_opts = (char *)malloc(220); + if(mountent.mnt_opts) { + char * mount_user = getusername(); + memset(mountent.mnt_opts,0,200); + if(flags & MS_RDONLY) + strlcat(mountent.mnt_opts,"ro",220); + else + strlcat(mountent.mnt_opts,"rw",220); + if(flags & MS_MANDLOCK) + strlcat(mountent.mnt_opts,",mand",220); + if(flags & MS_NOEXEC) + strlcat(mountent.mnt_opts,",noexec",220); + if(flags & MS_NOSUID) + strlcat(mountent.mnt_opts,",nosuid",220); + if(flags & MS_NODEV) + strlcat(mountent.mnt_opts,",nodev",220); + if(flags & MS_SYNCHRONOUS) + strlcat(mountent.mnt_opts,",sync",220); + if(mount_user) { + if(getuid() != 0) { + strlcat(mountent.mnt_opts, + ",user=", 220); + strlcat(mountent.mnt_opts, + mount_user, 220); } } - mountent.mnt_freq = 0; - mountent.mnt_passno = 0; - rc = addmntent(pmntfile,&mountent); - endmntent(pmntfile); - unlock_mtab(); - SAFE_FREE(mountent.mnt_opts); - if (rc) - rc = EX_FILEIO; } + mountent.mnt_freq = 0; + mountent.mnt_passno = 0; + rc = addmntent(pmntfile,&mountent); + endmntent(pmntfile); + unlock_mtab(); + SAFE_FREE(mountent.mnt_opts); + if (rc) + rc = EX_FILEIO; mount_exit: if(mountpassword) { int len = strlen(mountpassword); @@ -1481,6 +1498,8 @@ mount_exit: SAFE_FREE(mountpassword); } + if (addrhead) + freeaddrinfo(addrhead); SAFE_FREE(options); SAFE_FREE(orgoptions); SAFE_FREE(resolved_path); -- 2.34.1