ref: c76cc12a1799ce214b07882eb6f4ab0906c0151b
dir: /sys/src/cmd/auth/acmed.c/
#include <u.h> #include <libc.h> #include <json.h> #include <mp.h> #include <libsec.h> #include <auth.h> #include <authsrv.h> typedef struct Hdr Hdr; #pragma varargck type "E" char* struct Hdr { char *name; char *val; int nval; }; #define Keyspec "proto=rsa service=acme role=sign hash=sha256 acct=%s" #define Contenttype "contenttype application/jose+json" #define between(x,min,max) (((min-1-x) & (x-max-1))>>8) int debug; int (*challengefn)(char*, char*, char*, int*); char *keyspec; char *provider = "https://acme-v02.api.letsencrypt.org/directory"; /* default endpoint */ char *challengecmd; char *challengeout; char *keyid; char *epnewnonce; char *epnewacct; char *epneworder; char *eprevokecert; char *epkeychange; char *jwsthumb; JSON *jwskey; #define dprint(...) if(debug)fprint(2, __VA_ARGS__); char* evsmprint(char *fmt, va_list ap) { char *r; if((r = vsmprint(fmt, ap)) == nil) abort(); return r; } char* esmprint(char *fmt, ...) { va_list ap; char *r; va_start(ap, fmt); r = evsmprint(fmt, ap); va_end(ap); return r; } int encurl64chr(int o) { int c; c = between(o, 0, 25) & ('A'+o); c |= between(o, 26, 51) & ('a'+(o-26)); c |= between(o, 52, 61) & ('0'+(o-52)); c |= between(o, 62, 62) & ('-'); c |= between(o, 63, 63) & ('_'); return c; } char* encurl64(void *in, int n) { int lim; char *out, *p; lim = 4*n/3 + 5; if((out = malloc(lim)) == nil) abort(); enc64x(out, lim, in, n, encurl64chr); if((p = strchr(out, '=')) != nil) *p = 0; return out; } char* signRS256(char *hdr, char *prot) { uchar hash[SHA2_256dlen]; DigestState *s; AuthRpc *rpc; int afd; char *r; if((afd = open("/mnt/factotum/rpc", ORDWR|OCEXEC)) < 0) return nil; if((rpc = auth_allocrpc(afd)) == nil){ close(afd); return nil; } if(auth_rpc(rpc, "start", keyspec, strlen(keyspec)) != ARok){ auth_freerpc(rpc); close(afd); return nil; } s = sha2_256((uchar*)hdr, strlen(hdr), nil, nil); s = sha2_256((uchar*)".", strlen("."), nil, s); sha2_256((uchar*)prot, strlen(prot), hash, s); if(auth_rpc(rpc, "write", hash, sizeof(hash)) != ARok) sysfatal("sign: write hash: %r"); if(auth_rpc(rpc, "read", nil, 0) != ARok) sysfatal("sign: read sig: %r"); r = encurl64(rpc->arg, rpc->narg); auth_freerpc(rpc); close(afd); return r; } /* * Reads all available data from an fd. * guarantees returned value is terminated. */ static void* slurp(int fd, int *n) { char *b; int r, sz; *n = 0; sz = 32; if((b = malloc(sz)) == nil) abort(); while(1){ if(*n + 1 == sz){ sz *= 2; if((b = realloc(b, sz)) == nil) abort(); } r = read(fd, b + *n, sz - *n - 1); if(r == 0) break; if(r == -1){ free(b); return nil; } *n += r; } b[*n] = 0; return b; } static int webopen(char *url, char *dir, int ndir) { char buf[16]; int n, cfd, conn; if((cfd = open("/mnt/web/clone", ORDWR|OCEXEC)) == -1) return -1; if((n = read(cfd, buf, sizeof(buf)-1)) == -1) goto Error; buf[n] = 0; conn = atoi(buf); if(fprint(cfd, "url %s", url) == -1) goto Error; snprint(dir, ndir, "/mnt/web/%d", conn); return cfd; Error: close(cfd); return -1; } static char* get(char *url, int *n) { char *r, dir[64], path[80]; int cfd, dfd; r = nil; dfd = -1; if((cfd = webopen(url, dir, sizeof(dir))) == -1) goto Error; snprint(path, sizeof(path), "%s/%s", dir, "body"); if((dfd = open(path, OREAD|OCEXEC)) == -1) goto Error; r = slurp(dfd, n); Error: if(dfd != -1) close(dfd); if(cfd != -1) close(cfd); return r; } static char* post(char *url, char *buf, int nbuf, int *nret, Hdr *h) { char *r, dir[64], path[80]; int cfd, dfd, hfd, ok; r = nil; ok = 0; dfd = -1; hfd = -1; if((cfd = webopen(url, dir, sizeof(dir))) == -1) goto Error; if(write(cfd, Contenttype, strlen(Contenttype)) == -1) goto Error; snprint(path, sizeof(path), "%s/%s", dir, "postbody"); if((dfd = open(path, OWRITE|OCEXEC)) == -1) goto Error; if(write(dfd, buf, nbuf) != nbuf) goto Error; close(dfd); snprint(path, sizeof(path), "%s/%s", dir, "body"); if((dfd = open(path, OREAD|OCEXEC)) == -1) goto Error; if(h != nil){ snprint(path, sizeof(path), "%s/%s", dir, h->name); if((hfd = open(path, OREAD|OCEXEC)) == -1) goto Error; if((h->val = slurp(hfd, &h->nval)) == nil) goto Error; } if((r = slurp(dfd, nret)) == nil) goto Error; ok = 1; Error: if(hfd != -1) close(hfd); if(dfd != -1) close(dfd); if(cfd != -1) close(cfd); if(!ok && h != nil){ free(h->val); h->val = nil; h->nval = 0; } return r; } static int endpoints(void) { JSON *j; JSONEl *e; char *s; int n; if((s = get(provider, &n)) == nil) sysfatal("get %s: %r", provider); if((j = jsonparse(s)) == nil) sysfatal("parse endpoints: %r"); if(j->t != JSONObject) sysfatal("expected object"); for(e = j->first; e != nil; e = e->next){ if(e->val->t != JSONString) continue; if(strcmp(e->name, "keyChange") == 0) epkeychange = strdup(e->val->s); else if(strcmp(e->name, "newAccount") == 0) epnewacct = strdup(e->val->s); else if(strcmp(e->name, "newNonce") == 0) epnewnonce = strdup(e->val->s); else if(strcmp(e->name, "newOrder") == 0) epneworder = strdup(e->val->s); else if(strcmp(e->name, "revokeCert") == 0) eprevokecert = strdup(e->val->s); } jsonfree(j); free(s); if(epnewnonce==nil|| epnewacct==nil || epneworder==nil || eprevokecert==nil || epkeychange==nil) sysfatal("missing directory entries"); return 0; } static char* getnonce(void) { char *r, dir[64], path[80]; int n, cfd, dfd, hfd; r = nil; dfd = -1; hfd = -1; if((cfd = webopen(epnewnonce, dir, sizeof(dir))) == -1) goto Error; fprint(cfd, "request HEAD"); snprint(path, sizeof(path), "%s/%s", dir, "body"); if((dfd = open(path, OREAD|OCEXEC)) == -1) goto Error; snprint(path, sizeof(path), "%s/%s", dir, "replaynonce"); if((hfd = open(path, OREAD|OCEXEC)) == -1) goto Error; r = slurp(hfd, &n); Error: if(hfd != -1) close(hfd); if(dfd != -1) close(dfd); close(cfd); return r; } char* jwsenc(char *hdr, char *msg, int *nbuf) { char *h, *m, *s, *r; h = encurl64(hdr, strlen(hdr)); m = encurl64(msg, strlen(msg)); s = signRS256(h, m); if(s == nil) return nil; r = esmprint( "{\n" "\"protected\": \"%s\",\n" "\"payload\": \"%s\",\n" "\"signature\": \"%s\"\n" "}\n", h, m, s); *nbuf = strlen(r); free(h); free(m); free(s); return r; } char* jwsheader(char *url) { char *nonce; if((nonce = getnonce()) == nil) sysfatal("get nonce: %r"); return esmprint( "{" "\"alg\": \"RS256\"," "\"nonce\": \"%E\"," "\"kid\": \"%E\"," "\"url\": \"%E\"" "}", nonce, keyid, url); } char* jwsrequest(char *url, int *nresp, Hdr *h, char *fmt, ...) { char *hdr, *msg, *req, *resp; int nreq; va_list ap; va_start(ap, fmt); hdr = jwsheader(url); msg = evsmprint(fmt, ap); req = jwsenc(hdr, msg, &nreq); dprint("req=\"%s\"\n", req); resp = post(url, req, nreq, nresp, h); free(hdr); free(req); free(msg); va_end(ap); dprint("resp=%s\n", resp); return resp; } static void mkaccount(char *addr) { char *nonce, *hdr, *msg, *req, *resp; int nreq, nresp; Hdr loc = { "location" }; if((nonce = getnonce()) == nil) sysfatal("get nonce: %r"); hdr = esmprint( "{" "\"alg\": \"RS256\"," "\"jwk\": %J," "\"nonce\": \"%E\"," "\"url\": \"%E\"" "}", jwskey, nonce, epnewacct); msg = esmprint( "{" "\"termsOfServiceAgreed\": true," "\"contact\": [\"mailto:%E\"]" "}", addr); free(nonce); if((req = jwsenc(hdr, msg, &nreq)) == nil) sysfatal("failed to sign: %r"); dprint("req=\"%s\"\n", req); if((resp = post(epnewacct, req, nreq, &nresp, &loc)) == nil) sysfatal("failed req: %r"); dprint("resp=%s, loc=%s\n", resp, loc.val); keyid = loc.val; } static char* idn(char *dom) { static char buf[256]; if(utf2idn(dom, buf, sizeof(buf)) >= 0) return buf; return dom; } static JSON* submitorder(char **dom, int ndom, Hdr *hdr) { char *req, *resp, *sep, rbuf[8192]; int nresp, i; JSON *r; sep = ""; req = seprint(rbuf, rbuf+sizeof(rbuf), "{" " \"identifiers\": ["); for(i = 0; i < ndom; i++){ req = seprint(req, rbuf+sizeof(rbuf), "%s{" " \"type\": \"dns\"," " \"value\": \"%E\"" "}", sep, idn(dom[i])); sep = ","; } req = seprint(req, rbuf+sizeof(rbuf), " ]" "}"); if(req - rbuf < 2) sysfatal("truncated order"); resp = jwsrequest(epneworder, &nresp, hdr, "%s", rbuf); if(resp == nil) sysfatal("submit order: %r"); if((r = jsonparse(resp)) == nil) sysfatal("parse order: %r"); free(resp); return r; } static void hashauthbuf(char *buf, int nbuf) { uchar hash[SHA2_256dlen]; char *enc; sha2_256((uchar*)buf, strlen(buf), hash, nil); if((enc = encurl64(hash, sizeof(hash))) == nil) sysfatal("hashbuf: %r"); if(snprint(buf, nbuf, "%s", enc) != strlen(enc)) sysfatal("hashbuf: buffer too small, truncated"); free(enc); } static int runchallenge(char *ty, char *dom, char *tok, int *matched) { char auth[1024]; Waitmsg *w; int pid; snprint(auth, sizeof(auth), "%s.%s", tok, jwsthumb); if(strcmp(ty, "dns-01") == 0) hashauthbuf(auth, sizeof(auth)); pid = fork(); switch(pid){ case -1: return -1; case 0: dup(1, 2); execl(challengecmd, challengecmd, ty, dom, tok, auth, nil); sysfatal("%s: %r", challengecmd); } while((w = wait()) != nil){ if(w->pid != pid){ free(w); continue; } if(w->msg[0] == '\0'){ free(w); *matched = 1; return 0; } werrstr("%s", w->msg); free(w); return -1; } return -1; } static int httpchallenge(char *ty, char *, char *tok, int *matched) { char path[1024]; int fd, r; if(strcmp(ty, "http-01") != 0) return -1; *matched = 1; snprint(path, sizeof(path), "%s/%s", challengeout, tok); if((fd = create(path, OWRITE|OCEXEC, 0666)) == -1) return -1; r = fprint(fd, "%s.%s\n", tok, jwsthumb); close(fd); return r; } static int dnschallenge(char *ty, char *dom, char *tok, int *matched) { char auth[1024]; int fd; if(strcmp(ty, "dns-01") != 0) return -1; *matched = 1; snprint(auth, sizeof(auth), "%s.%s", tok, jwsthumb); hashauthbuf(auth, sizeof(auth)); if((fd = create(challengeout, OWRITE|OCEXEC, 0666)) == -1){ werrstr("could not create challenge: %r"); return -1; } if(fprint(fd,"dom=_acme-challenge.%s soa=\n\ttxt=\"%s\"\n", dom, auth) == -1){ werrstr("could not write challenge: %r"); close(fd); return -1; } close(fd); if((fd = open("/net/dns", OWRITE|OCEXEC)) == -1){ werrstr("could not open dns ctl: %r"); return -1; } if(fprint(fd, "refresh") == -1){ werrstr("could not write dns refresh: %r"); close(fd); return -1; } close(fd); return 0; } static int challenge(JSON *j, char *authurl, JSON *id, char *dom[], int ndom, int *matched, int wild) { JSON *dn, *ty, *url, *tok, *poll, *state; char *resp; int i, nresp; if((ty = jsonbyname(j, "type")) == nil) return -1; if((url = jsonbyname(j, "url")) == nil) return -1; if((tok = jsonbyname(j, "token")) == nil) return -1; if(ty->t != JSONString || url->t != JSONString || tok->t != JSONString) { werrstr("invalid challenge"); return -1; } if((dn = jsonbyname(id, "value")) == nil) return -1; if(dn->t != JSONString) { werrstr("invalid identifier"); return -1; } /* make sure the identifier matches the csr */ for(i = 0; i < ndom; i++){ /* if we got a wildcard certificate, the returned identifier has the *. removed */ if(wild && strncmp(dom[i], "*.", 2) == 0) dom[i] += 2; if(cistrcmp(idn(dom[i]), dn->s) == 0) break; } if(i >= ndom){ werrstr("unknown challenge identifier '%s'", dn->s); return -1; } dprint("trying challenge %s for %s (%s)\n", ty->s, dom[i], dn->s); if(challengefn(ty->s, dom[i], tok->s, matched) == -1){ dprint("challengefn failed: %r\n"); return -1; } if((resp = jwsrequest(url->s, &nresp, nil, "{}")) == nil) sysfatal("challenge: post %s: %r", url->s); free(resp); for(i = 0; i < 60; i++){ sleep(1000); if((resp = jwsrequest(authurl, &nresp, nil, "")) == nil) sysfatal("challenge: post %s: %r", url->s); if((poll = jsonparse(resp)) == nil){ free(resp); return -1; } if((state = jsonbyname(poll, "status")) != nil && state->t == JSONString){ if(strcmp(state->s, "valid") == 0){ jsonfree(poll); return 0; } else if(strcmp(state->s, "pending") != 0){ fprint(2, "error: %J", poll); werrstr("status '%s'", state->s); jsonfree(poll); return -1; } } jsonfree(poll); } werrstr("timeout"); return -1; } static int dochallenges(char *dom[], int ndom, JSON *order) { JSON *chals, *j, *cl, *id, *wc; JSONEl *ae, *ce; int nresp, matched, wild; char *resp; if((j = jsonbyname(order, "authorizations")) == nil){ werrstr("parse response: missing authorizations"); return -1; } if(j->t != JSONArray){ werrstr("parse response: authorizations must be array"); return -1; } for(ae = j->first; ae != nil; ae = ae->next){ if(ae->val->t != JSONString){ werrstr("challenge: auth must be url"); return -1; } if((resp = jwsrequest(ae->val->s, &nresp, nil, "")) == nil){ werrstr("challenge: request %s: %r", ae->val->s); return -1; } if((chals = jsonparse(resp)) == nil){ werrstr("invalid challenge: %r"); return -1; } if((id = jsonbyname(chals, "identifier")) == nil){ werrstr("missing identifier"); jsonfree(chals); return -1; } if((cl = jsonbyname(chals, "challenges")) == nil){ werrstr("missing challenge"); jsonfree(chals); return -1; } wild = 0; if((wc = jsonbyname(chals, "wildcard")) != nil){ if(wc->t == JSONBool && wc->n == 1) wild = 1; } matched = 0; for(ce = cl->first; ce != nil; ce = ce->next){ if(challenge(ce->val, ae->val->s, id, dom, ndom, &matched, wild) == 0) break; if(matched) werrstr("could not complete challenge: %r"); } if(!matched) sysfatal("no matching auth type: %r"); jsonfree(chals); free(resp); } return 0; } static int submitcsr(JSON *order, char *b64csr) { char *resp; int nresp; JSON *j; if((j = jsonbyname(order, "finalize")) == nil) sysfatal("parse response: missing authorizations"); if(j->t != JSONString) werrstr("parse response: finalizer must be string"); if((resp = jwsrequest(j->s, &nresp, nil, "{\"csr\":\"%E\"}", b64csr)) == nil) sysfatal("submit csr: %r"); free(resp); return 0; } static int fetchcert(char *url) { JSON *cert, *poll, *state; int i, r, nresp; char *resp; poll = nil; for(i = 0; i < 60; i++){ sleep(1000); if((resp = jwsrequest(url, &nresp, nil, "")) == nil) return -1; if((poll = jsonparse(resp)) == nil){ free(resp); return -1; } free(resp); if((state = jsonbyname(poll, "status")) != nil && state->t == JSONString){ if(strcmp(state->s, "valid") == 0) break; else if(strcmp(state->s, "pending") != 0 && strcmp(state->s, "processing") != 0){ fprint(2, "error: %J", poll); werrstr("invalid request: %s", state->s); jsonfree(poll); return -1; } } jsonfree(poll); } if(poll == nil){ werrstr("timed out"); return -1; } if((cert = jsonbyname(poll, "certificate")) == nil || cert->t != JSONString){ werrstr("missing cert url in response"); jsonfree(poll); return -1; } if((resp = jwsrequest(cert->s, &nresp, nil, "")) == nil){ jsonfree(poll); return -1; } jsonfree(poll); r = write(1, resp, nresp); free(resp); if(r != nresp) return -1; return 0; } static void getcert(char *csrpath) { char *csr, *dom[64], subj[2048]; uchar *der; int nder, ndom, fd; RSApub *rsa; Hdr loc = { "location" }; JSON *o; if((fd = open(csrpath, OREAD|OCEXEC)) == -1) sysfatal("open %s: %r", csrpath); if((der = slurp(fd, &nder)) == nil) sysfatal("read %s: %r", csrpath); close(fd); if((rsa = X509reqtoRSApub(der, nder, subj, sizeof(subj))) == nil) sysfatal("decode csr: %r"); rsapubfree(rsa); if((csr = encurl64(der, nder)) == nil) sysfatal("encode %s: %r", csrpath); free(der); dprint("subject: %s\n", subj); if((ndom = getfields(subj, dom, nelem(dom), 1, ", ")) == nelem(dom)) sysfatal("too man domains"); if((o = submitorder(dom, ndom, &loc)) == nil) sysfatal("order: %r"); if(dochallenges(dom, ndom, o) == -1) sysfatal("challenge: %r"); if(submitcsr(o, csr) == -1) sysfatal("signing cert: %r"); if(fetchcert(loc.val) == -1) sysfatal("saving cert: %r"); free(csr); } static int Econv(Fmt *f) { char *s; Rune r; int w; w = 0; s = va_arg(f->args, char*); while(*s){ s += chartorune(&r, s); if(r == '\\' || r == '\"') w += fmtrune(f, '\\'); w += fmtrune(f, r); } return w; } static int loadkey(char *path) { uchar h[SHA2_256dlen]; char key[8192]; JSON *j, *e, *kty, *n; DigestState *ds; int fd, nr; if((fd = open(path, OREAD|OCEXEC)) == -1) return -1; nr = readn(fd, key, sizeof(key)); close(fd); if(nr == -1) return -1; key[nr] = 0; if((j = jsonparse(key)) == nil) return -1; if((e = jsonbyname(j, "e")) == nil || e->t != JSONString) return -1; if((kty = jsonbyname(j, "kty")) == nil || kty->t != JSONString) return -1; if((n = jsonbyname(j, "n")) == nil || n->t != JSONString) return -1; ds = sha2_256((uchar*)"{\"e\":\"", 6, nil, nil); ds = sha2_256((uchar*)e->s, strlen(e->s), nil, ds); ds = sha2_256((uchar*)"\",\"kty\":\"", 9, nil, ds); ds = sha2_256((uchar*)kty->s, strlen(kty->s), nil, ds); ds = sha2_256((uchar*)"\",\"n\":\"", 7, nil, ds); ds = sha2_256((uchar*)n->s, strlen(n->s), nil, ds); sha2_256((uchar*)"\"}", 2, h, ds); jwskey = j; jwsthumb = encurl64(h, sizeof(h)); return 0; } static void usage(void) { fprint(2, "usage: %s [-a acctkey] [-e cmd | -o chalout -t type] [-p provider] acct csr\n", argv0); exits("usage"); } void main(int argc, char **argv) { char *acctkey, *ct, *co; JSONfmtinstall(); fmtinstall('E', Econv); ct = nil; co = nil; acctkey = nil; ARGBEGIN{ case 'd': debug++; break; case 'a': acctkey = EARGF(usage()); break; case 'e': challengecmd = EARGF(usage()); break; case 'o': co = EARGF(usage()); break; case 't': ct = EARGF(usage()); break; case 'p': provider = EARGF(usage()); break; default: usage(); break; }ARGEND; if(challengecmd != nil){ if(ct != nil || co != nil) usage(); challengeout = "/dev/null"; challengefn = runchallenge; }else if(ct == nil || strcmp(ct, "http") == 0){ challengeout = (co != nil) ? co : "/usr/web/.well-known/acme-challenge"; challengefn = httpchallenge; }else if(strcmp(ct, "dns") == 0){ challengeout = (co != nil) ? co : "/lib/ndb/dnschallenge"; challengefn = dnschallenge; }else { sysfatal("unknown challenge type '%s'", ct); } if(argc != 2) usage(); if(acctkey == nil) acctkey = esmprint("/sys/lib/tls/acmed/%s.pub", argv[0]); if((keyspec = smprint(Keyspec, argv[0])) == nil) sysfatal("smprint: %r"); if(loadkey(acctkey) == -1) sysfatal("load key: %r"); if(endpoints() == -1) sysfatal("endpoints: %r"); mkaccount(argv[0]); getcert(argv[1]); exits(nil); }