diff options
Diffstat (limited to 'lib')
-rw-r--r-- | lib/libstand/bootp.c | 328 |
1 files changed, 328 insertions, 0 deletions
diff --git a/lib/libstand/bootp.c b/lib/libstand/bootp.c index b1bc543..4ddfa6c 100644 --- a/lib/libstand/bootp.c +++ b/lib/libstand/bootp.c @@ -47,6 +47,12 @@ __FBSDID("$FreeBSD$"); #define BOOTP_DEBUGxx #define SUPPORT_DHCP +#define DHCP_ENV_NOVENDOR 1 /* do not parse vendor options */ +#define DHCP_ENV_PXE 10 /* assume pxe vendor options */ +#define DHCP_ENV_FREEBSD 11 /* assume freebsd vendor options +/* set DHCP_ENV to one of the values above to export dhcp options to kenv */ +#define DHCP_ENV DHCP_ENV_NO_VENDOR + #include "stand.h" #include "net.h" #include "netif.h" @@ -72,6 +78,13 @@ static int vend_rfc1048(u_char *, u_int); static void vend_cmu(u_char *); #endif +#ifdef DHCP_ENV /* export the dhcp response to kenv */ +struct dhcp_opt; +static void setenv_(u_char *cp, u_char *ep, struct dhcp_opt *opts); +#else +#define setenv_(a, b, c) +#endif + #ifdef SUPPORT_DHCP static char expected_dhcpmsgtype = -1, dhcp_ok; struct in_addr dhcp_serverip; @@ -351,6 +364,8 @@ vend_rfc1048(cp, len) /* Step over magic cookie */ cp += sizeof(int); + setenv_(cp, ep, NULL); + while (cp < ep) { tag = *cp++; size = *cp++; @@ -412,3 +427,316 @@ vend_cmu(cp) } } #endif + +#ifdef DHCP_ENV +/* + * Parse DHCP options and store them into kenv variables. + * Original code from Danny Braniss, modifications by Luigi Rizzo. + * + * The parser is driven by tables which specify the type and name of + * each dhcp option and how it appears in kenv. + * The first entry in the list contains the prefix used to set the kenv + * name (including the . if needed), the last entry must have a 0 tag. + * Entries do not need to be sorted though it helps for readability. + * + * Certain vendor-specific tables can be enabled according to DHCP_ENV. + * Set it to 0 if you don't want any. + */ +enum opt_fmt { __NONE = 0, + __8 = 1, __16 = 2, __32 = 4, /* Unsigned fields, value=size */ + __IP, /* IPv4 address */ + __TXT, /* C string */ + __BYTES, /* byte sequence, printed %02x */ + __INDIR, /* name=value */ + __ILIST, /* name=value;name=value ... */ + __VE, /* vendor specific, recurse */ +}; + +struct dhcp_opt { + uint8_t tag; + uint8_t fmt; + const char *desc; +}; + +static struct dhcp_opt vndr_opt[] = { /* Vendor Specific Options */ +#if DHCP_ENV == DHCP_ENV_FREEBSD /* FreeBSD table in the original code */ + {0, 0, "FreeBSD"}, /* prefix */ + {1, __TXT, "kernel"}, + {2, __TXT, "kernelname"}, + {3, __TXT, "kernel_options"}, + {4, __IP, "usr-ip"}, + {5, __TXT, "conf-path"}, + {6, __TXT, "rc.conf0"}, + {7, __TXT, "rc.conf1"}, + {8, __TXT, "rc.conf2"}, + {9, __TXT, "rc.conf3"}, + {10, __TXT, "rc.conf4"}, + {11, __TXT, "rc.conf5"}, + {12, __TXT, "rc.conf6"}, + {13, __TXT, "rc.conf7"}, + {14, __TXT, "rc.conf8"}, + {15, __TXT, "rc.conf9"}, + + {20, __TXT, "boot.nfsroot.options"}, + + {245, __INDIR, ""}, + {246, __INDIR, ""}, + {247, __INDIR, ""}, + {248, __INDIR, ""}, + {249, __INDIR, ""}, + {250, __INDIR, ""}, + {251, __INDIR, ""}, + {252, __INDIR, ""}, + {253, __INDIR, ""}, + {254, __INDIR, ""}, + +#elif DHCP_ENV == DHCP_ENV_PXE /* some pxe options, RFC4578 */ + {0, 0, "pxe"}, /* prefix */ + {93, __16, "system-architecture"}, + {94, __BYTES, "network-interface"}, + {97, __BYTES, "machine-identifier"}, +#else /* default (empty) table */ + {0, 0, ""}, /* prefix */ +#endif + {0, __TXT, "%soption-%d"} +}; + +static struct dhcp_opt dhcp_opt[] = { + /* DHCP Option names, formats and codes, from RFC2132. */ + {0, 0, "dhcp."}, // prefix + {1, __IP, "subnet-mask"}, + {2, __32, "time-offset"}, /* this is signed */ + {3, __IP, "routers"}, + {4, __IP, "time-servers"}, + {5, __IP, "ien116-name-servers"}, + {6, __IP, "domain-name-servers"}, + {7, __IP, "log-servers"}, + {8, __IP, "cookie-servers"}, + {9, __IP, "lpr-servers"}, + {10, __IP, "impress-servers"}, + {11, __IP, "resource-location-servers"}, + {12, __TXT, "host-name"}, + {13, __16, "boot-size"}, + {14, __TXT, "merit-dump"}, + {15, __TXT, "domain-name"}, + {16, __IP, "swap-server"}, + {17, __TXT, "root-path"}, + {18, __TXT, "extensions-path"}, + {19, __8, "ip-forwarding"}, + {20, __8, "non-local-source-routing"}, + {21, __IP, "policy-filter"}, + {22, __16, "max-dgram-reassembly"}, + {23, __8, "default-ip-ttl"}, + {24, __32, "path-mtu-aging-timeout"}, + {25, __16, "path-mtu-plateau-table"}, + {26, __16, "interface-mtu"}, + {27, __8, "all-subnets-local"}, + {28, __IP, "broadcast-address"}, + {29, __8, "perform-mask-discovery"}, + {30, __8, "mask-supplier"}, + {31, __8, "perform-router-discovery"}, + {32, __IP, "router-solicitation-address"}, + {33, __IP, "static-routes"}, + {34, __8, "trailer-encapsulation"}, + {35, __32, "arp-cache-timeout"}, + {36, __8, "ieee802-3-encapsulation"}, + {37, __8, "default-tcp-ttl"}, + {38, __32, "tcp-keepalive-interval"}, + {39, __8, "tcp-keepalive-garbage"}, + {40, __TXT, "nis-domain"}, + {41, __IP, "nis-servers"}, + {42, __IP, "ntp-servers"}, + {43, __VE, "vendor-encapsulated-options"}, + {44, __IP, "netbios-name-servers"}, + {45, __IP, "netbios-dd-server"}, + {46, __8, "netbios-node-type"}, + {47, __TXT, "netbios-scope"}, + {48, __IP, "x-font-servers"}, + {49, __IP, "x-display-managers"}, + {50, __IP, "dhcp-requested-address"}, + {51, __32, "dhcp-lease-time"}, + {52, __8, "dhcp-option-overload"}, + {53, __8, "dhcp-message-type"}, + {54, __IP, "dhcp-server-identifier"}, + {55, __8, "dhcp-parameter-request-list"}, + {56, __TXT, "dhcp-message"}, + {57, __16, "dhcp-max-message-size"}, + {58, __32, "dhcp-renewal-time"}, + {59, __32, "dhcp-rebinding-time"}, + {60, __TXT, "vendor-class-identifier"}, + {61, __TXT, "dhcp-client-identifier"}, + {64, __TXT, "nisplus-domain"}, + {65, __IP, "nisplus-servers"}, + {66, __TXT, "tftp-server-name"}, + {67, __TXT, "bootfile-name"}, + {68, __IP, "mobile-ip-home-agent"}, + {69, __IP, "smtp-server"}, + {70, __IP, "pop-server"}, + {71, __IP, "nntp-server"}, + {72, __IP, "www-server"}, + {73, __IP, "finger-server"}, + {74, __IP, "irc-server"}, + {75, __IP, "streettalk-server"}, + {76, __IP, "streettalk-directory-assistance-server"}, + {77, __TXT, "user-class"}, + {85, __IP, "nds-servers"}, + {86, __TXT, "nds-tree-name"}, + {87, __TXT, "nds-context"}, + {210, __TXT, "authenticate"}, + + /* use the following entries for arbitrary variables */ + {246, __ILIST, ""}, + {247, __ILIST, ""}, + {248, __ILIST, ""}, + {249, __ILIST, ""}, + {250, __INDIR, ""}, + {251, __INDIR, ""}, + {252, __INDIR, ""}, + {253, __INDIR, ""}, + {254, __INDIR, ""}, + {0, __TXT, "%soption-%d"} +}; + +/* + * parse a dhcp response, set environment variables translating options + * names and values according to the tables above. Also set dhcp.tags + * to the list of selected tags. + */ +static void +setenv_(u_char *cp, u_char *ep, struct dhcp_opt *opts) +{ + u_char *ncp; + u_char tag; + char tags[512], *tp; /* the list of tags */ + +#define FLD_SEP ',' /* separator in list of elements */ + ncp = cp; + tp = tags; + if (opts == NULL) + opts = dhcp_opt; + + while (ncp < ep) { + unsigned int size; /* option size */ + char *vp, *endv, buf[256]; /* the value buffer */ + struct dhcp_opt *op; + + tag = *ncp++; /* extract tag and size */ + size = *ncp++; + cp = ncp; /* current payload */ + ncp += size; /* point to the next option */ + + if (tag == TAG_END) + break; + if (tag == 0) + continue; + + for (op = opts+1; op->tag && op->tag != tag; op++) + ; + /* if not found we end up on the default entry */ + + /* + * Copy data into the buffer. libstand does not have snprintf so we + * need to be careful with sprintf(). With strings, the source is + * always <256 char so shorter than the buffer so we are safe; with + * other arguments, the longest string is inet_ntoa which is 16 bytes + * so we make sure to have always enough room in the string before + * trying an sprint. + */ + vp = buf; + *vp = '\0'; + endv = buf + sizeof(buf) - 1 - 16; /* last valid write position */ + + switch(op->fmt) { + case __NONE: + break; /* should not happen */ + + case __VE: /* recurse, vendor specific */ + setenv_(cp, cp+size, vndr_opt); + break; + + case __IP: /* ip address */ + for (; size > 0 && vp < endv; size -= 4, cp += 4) { + struct in_addr in_ip; /* ip addresses */ + if (vp != buf) + *vp++ = FLD_SEP; + bcopy(cp, &in_ip.s_addr, sizeof(in_ip.s_addr)); + sprintf(vp, "%s", inet_ntoa(in_ip)); + vp += strlen(vp); + } + break; + + case __BYTES: /* opaque byte string */ + for (; size > 0 && vp < endv; size -= 1, cp += 1) { + sprintf(vp, "%02x", *cp); + vp += strlen(vp); + } + break; + + case __TXT: + bcopy(cp, buf, size); /* cannot overflow */ + buf[size] = 0; + break; + + case __32: + case __16: + case __8: /* op->fmt is also the length of each field */ + for (; size > 0 && vp < endv; size -= op->fmt, cp += op->fmt) { + uint32_t v; + if (op->fmt == __32) + v = (cp[0]<<24) + (cp[1]<<16) + (cp[2]<<8) + cp[3]; + else if (op->fmt == __16) + v = (cp[0]<<8) + cp[1]; + else + v = cp[0]; + if (vp != buf) + *vp++ = FLD_SEP; + sprintf(vp, "%u", v); + vp += strlen(vp); + } + break; + + case __INDIR: /* name=value */ + case __ILIST: /* name=value;name=value... */ + bcopy(cp, buf, size); /* cannot overflow */ + buf[size] = '\0'; + for (endv = buf; endv; endv = vp) { + u_char *s = NULL; /* semicolon ? */ + + /* skip leading whitespace */ + while (*endv && index(" \t\n\r", *endv)) + endv++; + vp = index(endv, '='); /* find name=value separator */ + if (!vp) + break; + *vp++ = 0; + if (op->fmt == __ILIST && (s = index(vp, ';'))) + *s++ = '\0'; + setenv(endv, vp, 1); + vp = s; /* prepare for next round */ + } + buf[0] = '\0'; /* option already done */ + } + + if (tp - tags < sizeof(tags) - 5) { /* add tag to the list */ + if (tp != tags) + *tp++ = FLD_SEP; + sprintf(tp, "%d", tag); + tp += strlen(tp); + } + if (buf[0]) { + char env[128]; /* the string name */ + + if (op->tag == 0) + sprintf(env, op->desc, opts[0].desc, tag); + else + sprintf(env, "%s%s", opts[0].desc, op->desc); + setenv(env, buf, 1); + } + } + if (tp != tags) { + char env[128]; /* the string name */ + sprintf(env, "%stags", opts[0].desc); + setenv(env, tags, 1); + } +} +#endif /* additional dhcp */ |