diff options
Diffstat (limited to 'os/port/dial.c')
| -rw-r--r-- | os/port/dial.c | 417 |
1 files changed, 417 insertions, 0 deletions
diff --git a/os/port/dial.c b/os/port/dial.c new file mode 100644 index 00000000..d07671dc --- /dev/null +++ b/os/port/dial.c @@ -0,0 +1,417 @@ +#include "u.h" +#include "../port/lib.h" +#include "mem.h" +#include "dat.h" +#include "fns.h" +#include "../port/error.h" +#include "kernel.h" + +typedef struct DS DS; + +static int call(char*, char*, DS*); +static int csdial(DS*); +static void _dial_string_parse(char*, DS*); +static int nettrans(char*, char*, int na, char*, int); + +enum +{ + Maxstring= 128, + Maxpath= 100 +}; + +struct DS +{ + char buf[Maxstring]; /* dist string */ + char *netdir; + char *proto; + char *rem; + char *local; /* other args */ + char *dir; + int *cfdp; +}; + +/* + * the dialstring is of the form '[/net/]proto!dest' + */ +int +kdial(char *dest, char *local, char *dir, int *cfdp) +{ + DS ds; + int rv; + char err[ERRMAX], alterr[ERRMAX]; + + ds.local = local; + ds.dir = dir; + ds.cfdp = cfdp; + + _dial_string_parse(dest, &ds); + if(ds.netdir) + return csdial(&ds); + + ds.netdir = "/net"; + rv = csdial(&ds); + if(rv >= 0) + return rv; + + err[0] = 0; + kerrstr(err, sizeof err); + if(strstr(err, "refused") != 0){ + kerrstr(err, sizeof err); + return rv; + } + + ds.netdir = "/net.alt"; + rv = csdial(&ds); + if(rv >= 0) + return rv; + + alterr[0] = 0; + kerrstr(alterr, sizeof err); + + if(strstr(alterr, "translate") || strstr(alterr, "does not exist")) + kerrstr(err, sizeof err); + else + kerrstr(alterr, sizeof alterr); + return rv; +} + +static int +csdial(DS *ds) +{ + int n, fd, rv; + char *p, buf[Maxstring], clone[Maxpath], err[ERRMAX], besterr[ERRMAX]; + + /* + * open connection server + */ + snprint(buf, sizeof(buf), "%s/cs", ds->netdir); + fd = kopen(buf, ORDWR); + if(fd < 0){ + /* no connection server, don't translate */ + snprint(clone, sizeof(clone), "%s/%s/clone", ds->netdir, ds->proto); + return call(clone, ds->rem, ds); + } + + /* + * ask connection server to translate + */ + sprint(buf, "%s!%s", ds->proto, ds->rem); + if(kwrite(fd, buf, strlen(buf)) < 0){ + kerrstr(err, sizeof err); + kclose(fd); + kwerrstr("%s (%s)", err, buf); + return -1; + } + + /* + * loop through each address from the connection server till + * we get one that works. + */ + *besterr = 0; + strcpy(err, Egreg); + rv = -1; + kseek(fd, 0, 0); + while((n = kread(fd, buf, sizeof(buf) - 1)) > 0){ + buf[n] = 0; + p = strchr(buf, ' '); + if(p == 0) + continue; + *p++ = 0; + rv = call(buf, p, ds); + if(rv >= 0) + break; + err[0] = 0; + kerrstr(err, sizeof err); + if(strstr(err, "does not exist") == 0) + memmove(besterr, err, sizeof besterr); + } + kclose(fd); + + if(rv < 0 && *besterr) + kerrstr(besterr, sizeof besterr); + else + kerrstr(err, sizeof err); + return rv; +} + +static int +call(char *clone, char *dest, DS *ds) +{ + int fd, cfd, n; + char name[Maxpath], data[Maxpath], err[ERRMAX], *p; + + cfd = kopen(clone, ORDWR); + if(cfd < 0){ + kerrstr(err, sizeof err); + kwerrstr("%s (%s)", err, clone); + return -1; + } + + /* get directory name */ + n = kread(cfd, name, sizeof(name)-1); + if(n < 0){ + kerrstr(err, sizeof err); + kclose(cfd); + kwerrstr("read %s: %s", clone, err); + return -1; + } + name[n] = 0; + for(p = name; *p == ' '; p++) + ; + sprint(name, "%ld", strtoul(p, 0, 0)); + p = strrchr(clone, '/'); + *p = 0; + if(ds->dir) + snprint(ds->dir, NETPATHLEN, "%s/%s", clone, name); + snprint(data, sizeof(data), "%s/%s/data", clone, name); + + /* connect */ + if(ds->local) + snprint(name, sizeof(name), "connect %s %s", dest, ds->local); + else + snprint(name, sizeof(name), "connect %s", dest); + if(kwrite(cfd, name, strlen(name)) < 0){ + err[0] = 0; + kerrstr(err, sizeof err); + kclose(cfd); + kwerrstr("%s (%s)", err, name); + return -1; + } + + /* open data connection */ + fd = kopen(data, ORDWR); + if(fd < 0){ + err[0] = 0; + kerrstr(err, sizeof err); + kwerrstr("%s (%s)", err, data); + kclose(cfd); + return -1; + } + if(ds->cfdp) + *ds->cfdp = cfd; + else + kclose(cfd); + + return fd; +} + +/* + * parse a dial string + */ +static void +_dial_string_parse(char *str, DS *ds) +{ + char *p, *p2; + + strncpy(ds->buf, str, Maxstring); + ds->buf[Maxstring-1] = 0; + + p = strchr(ds->buf, '!'); + if(p == 0) { + ds->netdir = 0; + ds->proto = "net"; + ds->rem = ds->buf; + } else { + if(*ds->buf != '/' && *ds->buf != '#'){ + ds->netdir = 0; + ds->proto = ds->buf; + } else { + for(p2 = p; *p2 != '/'; p2--) + ; + *p2++ = 0; + ds->netdir = ds->buf; + ds->proto = p2; + } + *p = 0; + ds->rem = p + 1; + } +} + +/* + * announce a network service. + */ +int +kannounce(char *addr, char *dir) +{ + int ctl, n, m; + char buf[NETPATHLEN]; + char buf2[Maxpath]; + char netdir[NETPATHLEN]; + char naddr[Maxpath]; + char *cp; + + /* + * translate the address + */ + if(nettrans(addr, naddr, sizeof(naddr), netdir, sizeof(netdir)) < 0) + return -1; + + /* + * get a control channel + */ + ctl = kopen(netdir, ORDWR); + if(ctl<0) + return -1; + cp = strrchr(netdir, '/'); + *cp = 0; + + /* + * find out which line we have + */ + n = sprint(buf, "%.*s/", sizeof buf, netdir); + m = kread(ctl, &buf[n], sizeof(buf)-n-1); + if(m <= 0){ + kclose(ctl); + return -1; + } + buf[n+m] = 0; + + /* + * make the call + */ + n = snprint(buf2, sizeof buf2, "announce %s", naddr); + if(kwrite(ctl, buf2, n)!=n){ + kclose(ctl); + return -1; + } + + /* + * return directory etc. + */ + if(dir) + strcpy(dir, buf); + return ctl; +} + +/* + * listen for an incoming call + */ +int +klisten(char *dir, char *newdir) +{ + int ctl, n, m; + char buf[NETPATHLEN]; + char *cp; + + /* + * open listen, wait for a call + */ + snprint(buf, sizeof buf, "%s/listen", dir); + ctl = kopen(buf, ORDWR); + if(ctl < 0) + return -1; + + /* + * find out which line we have + */ + strcpy(buf, dir); + cp = strrchr(buf, '/'); + *++cp = 0; + n = cp-buf; + m = kread(ctl, cp, sizeof(buf) - n - 1); + if(m <= 0){ + kclose(ctl); + return -1; + } + buf[n+m] = 0; + + /* + * return directory etc. + */ + if(newdir) + strcpy(newdir, buf); + return ctl; + +} + +/* + * perform the identity translation (in case we can't reach cs) + */ +static int +identtrans(char *netdir, char *addr, char *naddr, int na, char *file, int nf) +{ + char proto[Maxpath]; + char *p; + + USED(nf); + + /* parse the protocol */ + strncpy(proto, addr, sizeof(proto)); + proto[sizeof(proto)-1] = 0; + p = strchr(proto, '!'); + if(p) + *p++ = 0; + + snprint(file, nf, "%s/%s/clone", netdir, proto); + strncpy(naddr, p, na); + naddr[na-1] = 0; + + return 1; +} + +/* + * call up the connection server and get a translation + */ +static int +nettrans(char *addr, char *naddr, int na, char *file, int nf) +{ + int i, fd; + char buf[Maxpath]; + char netdir[NETPATHLEN]; + char *p, *p2; + long n; + + /* + * parse, get network directory + */ + p = strchr(addr, '!'); + if(p == 0){ + kwerrstr("bad dial string: %s", addr); + return -1; + } + if(*addr != '/'){ + strcpy(netdir, "/net"); + } else { + for(p2 = p; *p2 != '/'; p2--) + ; + i = p2 - addr; + if(i == 0 || i >= sizeof(netdir)){ + kwerrstr("bad dial string: %s", addr); + return -1; + } + strncpy(netdir, addr, i); + netdir[i] = 0; + addr = p2 + 1; + } + + /* + * ask the connection server + */ + sprint(buf, "%s/cs", netdir); + fd = kopen(buf, ORDWR); + if(fd < 0) + return identtrans(netdir, addr, naddr, na, file, nf); + if(kwrite(fd, addr, strlen(addr)) < 0){ + kclose(fd); + return -1; + } + kseek(fd, 0, 0); + n = kread(fd, buf, sizeof(buf)-1); + kclose(fd); + if(n <= 0) + return -1; + buf[n] = 0; + + /* + * parse the reply + */ + p = strchr(buf, ' '); + if(p == 0) + return -1; + *p++ = 0; + strncpy(naddr, p, na); + naddr[na-1] = 0; + strncpy(file, buf, nf); + file[nf-1] = 0; + return 0; +} |