ref: ca9d65e40b3f78d2580fff9ff1844bad1be08673
dir: /sys/src/cmd/upas/fs/pop3.c/
#include "common.h" #include <libsec.h> #include <auth.h> #include "dat.h" #pragma varargck type "M" uchar* #pragma varargck argpos pop3cmd 2 #define pdprint(p, ...) if((p)->debug) fprint(2, __VA_ARGS__); else{} typedef struct Popm Popm; struct Popm{ int mesgno; }; typedef struct Pop Pop; struct Pop { char *freep; /* free this to free the strings below */ char *host; char *user; char *port; int ppop; int refreshtime; int debug; int pipeline; int encrypted; int needtls; int notls; int needssl; Biobuf bin; /* open network connection */ Biobuf bout; int fd; char *lastline; /* from Brdstr */ }; static int mesgno(Message *m) { Popm *a; a = m->aux; return a->mesgno; } static char* geterrstr(void) { static char err[64]; err[0] = '\0'; errstr(err, sizeof(err)); return err; } /* * get pop3 response line , without worrying * about multiline responses; the clients * will deal with that. */ static int isokay(char *s) { return s!=nil && strncmp(s, "+OK", 3)==0; } static void pop3cmd(Pop *pop, char *fmt, ...) { char buf[128], *p; va_list va; va_start(va, fmt); vseprint(buf, buf + sizeof buf, fmt, va); va_end(va); p = buf + strlen(buf); if(p > buf + sizeof buf - 3) sysfatal("pop3 command too long"); pdprint(pop, "<- %s\n", buf); strcpy(p, "\r\n"); Bwrite(&pop->bout, buf, strlen(buf)); Bflush(&pop->bout); } static char* pop3resp(Pop *pop) { char *s; char *p; if((s = Brdstr(&pop->bin, '\n', 0)) == nil){ close(pop->fd); pop->fd = -1; return "unexpected eof"; } p = s + strlen(s) - 1; while(p >= s && (*p == '\r' || *p == '\n')) *p-- = '\0'; pdprint(pop, "-> %s\n", s); free(pop->lastline); pop->lastline = s; return s; } /* * get capability list, possibly start tls */ static char* pop3capa(Pop *pop) { char *s; int hastls; pop3cmd(pop, "CAPA"); if(!isokay(pop3resp(pop))) return nil; hastls = 0; for(;;){ s = pop3resp(pop); if(strcmp(s, ".") == 0 || strcmp(s, "unexpected eof") == 0) break; if(strcmp(s, "STLS") == 0) hastls = 1; if(strcmp(s, "PIPELINING") == 0) pop->pipeline = 1; if(strcmp(s, "EXPIRE 0") == 0) return "server does not allow mail to be left on server"; } if(hastls && !pop->notls){ pop3cmd(pop, "STLS"); if(!isokay(s = pop3resp(pop))) return s; Bterm(&pop->bin); Bterm(&pop->bout); if((pop->fd = wraptls(pop->fd, pop->host)) < 0) return geterrstr(); pop->encrypted = 1; Binit(&pop->bin, pop->fd, OREAD); Binit(&pop->bout, pop->fd, OWRITE); } return nil; } /* * log in using APOP if possible, password if allowed by user */ static char* pop3login(Pop *pop) { int n; char *s, *p, *q; char ubuf[128], user[128]; char buf[500]; UserPasswd *up; s = pop3resp(pop); if(!isokay(s)) return "error in initial handshake"; if(pop->user) snprint(ubuf, sizeof ubuf, " user=%q", pop->user); else ubuf[0] = '\0'; /* look for apop banner */ if(pop->ppop == 0 && (p = strchr(s, '<')) && (q = strchr(p + 1, '>'))) { *++q = '\0'; if((n=auth_respond(p, q - p, user, sizeof user, buf, sizeof buf, auth_getkey, "proto=apop role=client server=%q%s", pop->host, ubuf)) < 0) return "factotum failed"; if(user[0]=='\0') return "factotum did not return a user name"; if(s = pop3capa(pop)) return s; pop3cmd(pop, "APOP %s %.*s", user, utfnlen(buf, n), buf); if(!isokay(s = pop3resp(pop))) return s; return nil; } else { if(pop->ppop == 0) return "no APOP hdr from server"; if(s = pop3capa(pop)) return s; if(pop->needtls && !pop->encrypted) return "could not negotiate TLS"; up = auth_getuserpasswd(auth_getkey, "proto=pass service=pop dom=%q%s", pop->host, ubuf); if(up == nil) return "no usable keys found"; pop3cmd(pop, "USER %s", up->user); if(!isokay(s = pop3resp(pop))){ free(up); return s; } pop3cmd(pop, "PASS %s", up->passwd); free(up); if(!isokay(s = pop3resp(pop))) return s; return nil; } } /* * dial and handshake with pop server */ static char* pop3dial(Pop *pop) { char *err; if((pop->fd = dial(netmkaddr(pop->host, "net", pop->needssl ? "pop3s" : "pop3"), 0, 0, 0)) < 0) return geterrstr(); if(pop->needssl && (pop->fd = wraptls(pop->fd, pop->host)) < 0) return geterrstr(); pop->encrypted = pop->needssl; Binit(&pop->bin, pop->fd, OREAD); Binit(&pop->bout, pop->fd, OWRITE); if(err = pop3login(pop)) { close(pop->fd); return err; } return nil; } /* * close connection */ static void pop3hangup(Pop *pop) { pop3cmd(pop, "QUIT"); pop3resp(pop); close(pop->fd); } /* * download a single message */ static char* pop3download(Mailbox *mb, Pop *pop, Message *m) { char *s, *f[3], *wp, *ep; int l, sz, pos, n; Popm *a; a = m->aux; if(!pop->pipeline) pop3cmd(pop, "LIST %d", a->mesgno); if(!isokay(s = pop3resp(pop))) return s; if(tokenize(s, f, 3) != 3) return "syntax error in LIST response"; if(atoi(f[1]) != a->mesgno) return "out of sync with pop3 server"; sz = atoi(f[2]) + 200; /* 200 because the plan9 pop3 server lies */ if(sz == 0) return "invalid size in LIST response"; m->start = wp = emalloc(sz + 1); ep = wp + sz; if(!pop->pipeline) pop3cmd(pop, "RETR %d", a->mesgno); if(!isokay(s = pop3resp(pop))) { m->start = nil; free(wp); return s; } s = nil; while(wp <= ep) { s = pop3resp(pop); if(strcmp(s, "unexpected eof") == 0) { free(m->start); m->start = nil; return "unexpected end of conversation"; } if(strcmp(s, ".") == 0) break; l = strlen(s) + 1; if(s[0] == '.') { s++; l--; } /* * grow by 10%/200bytes - some servers * lie about message sizes */ if(wp + l > ep) { pos = wp - m->start; n = sz/10; if(n < 200) n = 200; sz += n; m->start = erealloc(m->start, sz + 1); wp = m->start + pos; ep = m->start + sz; } memmove(wp, s, l - 1); wp[l-1] = '\n'; wp += l; } if(s == nil || strcmp(s, ".") != 0) return "out of sync with pop3 server"; m->end = wp; /* * make sure there's a trailing null * (helps in body searches) */ *m->end = 0; m->bend = m->rbend = m->end; m->header = m->start; m->size = m->end - m->start; if(m->digest == nil) digestmessage(mb, m); return nil; } /* * check for new messages on pop server * UIDL is not required by RFC 1939, but * netscape requires it, so almost every server supports it. * we'll use it to make our lives easier. */ static char* pop3read(Pop *pop, Mailbox *mb) { char *s, *p, *uidl, *f[2]; int mno, ignore; Message *m, *next, **l; Popm *a; /* Some POP servers disallow UIDL if the maildrop is empty. */ pop3cmd(pop, "STAT"); if(!isokay(s = pop3resp(pop))) return s; /* fetch message listing; note messages to grab */ l = &mb->root->part; if(strncmp(s, "+OK 0 ", 6) != 0) { pop3cmd(pop, "UIDL"); if(!isokay(s = pop3resp(pop))) return s; for(;;){ p = pop3resp(pop); if(strcmp(p, ".") == 0 || strcmp(p, "unexpected eof") == 0) break; if(tokenize(p, f, 2) != 2) continue; mno = atoi(f[0]); uidl = f[1]; if(strlen(uidl) > 75) /* RFC 1939 says 70 characters max */ continue; ignore = 0; while(*l != nil) { a = (*l)->aux; if(strcmp((*l)->idxaux, uidl) == 0){ if(a == 0){ m = *l; m->mallocd = 1; m->inmbox = 1; m->aux = a = emalloc(sizeof *a); } /* matches mail we already have, note mesgno for deletion */ a->mesgno = mno; ignore = 1; l = &(*l)->next; break; }else{ /* old mail no longer in box mark deleted */ (*l)->inmbox = 0; (*l)->deleted = Deleted; l = &(*l)->next; } } if(ignore) continue; m = newmessage(mb->root); m->mallocd = 1; m->inmbox = 1; m->idxaux = strdup(uidl); m->aux = a = emalloc(sizeof *a); a->mesgno = mno; /* chain in; will fill in message later */ *l = m; l = &m->next; } } /* whatever is left has been removed from the mbox, mark as deleted */ while(*l != nil) { (*l)->inmbox = 0; (*l)->deleted = Disappear; l = &(*l)->next; } /* download new messages */ if(pop->pipeline){ switch(rfork(RFPROC|RFMEM)){ case -1: eprint("pop3: rfork: %r\n"); pop->pipeline = 0; default: break; case 0: for(m = mb->root->part; m != nil; m = m->next){ if(m->start != nil || m->deleted) continue; Bprint(&pop->bout, "LIST %d\r\nRETR %d\r\n", mesgno(m), mesgno(m)); } Bflush(&pop->bout); _exits(""); } } for(m = mb->root->part; m != nil; m = next) { next = m->next; if(m->start != nil || m->deleted) continue; if(s = pop3download(mb, pop, m)) { eprint("pop3: download %d: %s\n", mesgno(m), s); unnewmessage(mb, mb->root, m); continue; } parse(mb, m, 1, 0); } if(pop->pipeline) waitpid(); return nil; } /* * delete marked messages */ static void pop3purge(Pop *pop, Mailbox *mb) { Message *m; if(pop->pipeline){ switch(rfork(RFPROC|RFMEM)){ case -1: eprint("pop3: rfork: %r\n"); pop->pipeline = 0; default: break; case 0: for(m = mb->root->part; m != nil; m = m->next){ if(m->deleted && m->inmbox) Bprint(&pop->bout, "DELE %d\r\n", mesgno(m)); } Bflush(&pop->bout); _exits(""); } } for(m = mb->root->part; m != nil; m = m->next) { if(m->deleted && m->inmbox) { if(!pop->pipeline) pop3cmd(pop, "DELE %d", mesgno(m)); if(!isokay(pop3resp(pop))) continue; m->inmbox = 0; } } } /* connect to pop3 server, sync mailbox */ static char* pop3sync(Mailbox *mb) { char *err; Pop *pop; pop = mb->aux; if(err = pop3dial(pop)) goto out; if((err = pop3read(pop, mb)) == nil) pop3purge(pop, mb); pop3hangup(pop); out: mb->waketime = (ulong)time(0) + pop->refreshtime; return err; } static char Epop3ctl[] = "bad pop3 control message"; static char* pop3ctl(Mailbox *mb, int argc, char **argv) { int n; Pop *pop; pop = mb->aux; if(argc < 1) return Epop3ctl; if(argc==1 && strcmp(argv[0], "debug")==0){ pop->debug = 1; return nil; } if(argc==1 && strcmp(argv[0], "nodebug")==0){ pop->debug = 0; return nil; } if(strcmp(argv[0], "refresh")==0){ if(argc==1){ pop->refreshtime = 60; return nil; } if(argc==2){ n = atoi(argv[1]); if(n < 15) return Epop3ctl; pop->refreshtime = n; return nil; } } return Epop3ctl; } /* free extra memory associated with mb */ static void pop3close(Mailbox *mb) { Pop *pop; pop = mb->aux; free(pop->freep); free(pop); } static char* mkmbox(Pop *pop, char *p, char *e) { p = seprint(p, e, "%s/box/%s/pop.%s", MAILROOT, getlog(), pop->host); if(pop->user && strcmp(pop->user, getlog())) p = seprint(p, e, ".%s", pop->user); return p; } /* * open mailboxes of the form /pop/host/user or /apop/host/user */ char* pop3mbox(Mailbox *mb, char *path) { char *f[10]; int nf, apop, ppop, popssl, apopssl, apoptls, popnotls, apopnotls, poptls; Pop *pop; popssl = strncmp(path, "/pops/", 6) == 0; apopssl = strncmp(path, "/apops/", 7) == 0; poptls = strncmp(path, "/poptls/", 8) == 0; popnotls = strncmp(path, "/popnotls/", 10) == 0; ppop = popssl || poptls || popnotls || strncmp(path, "/pop/", 5) == 0; apoptls = strncmp(path, "/apoptls/", 9) == 0; apopnotls = strncmp(path, "/apopnotls/", 11) == 0; apop = apopssl || apoptls || apopnotls || strncmp(path, "/apop/", 6) == 0; if(!ppop && !apop) return Enotme; path = strdup(path); if(path == nil) return "out of memory"; nf = getfields(path, f, nelem(f), 0, "/"); if(nf != 3 && nf != 4) { free(path); return "bad pop3 path syntax /[a]pop[tls|ssl]/system[/user]"; } pop = emalloc(sizeof *pop); pop->freep = path; pop->host = f[2]; if(nf < 4) pop->user = nil; else pop->user = f[3]; pop->ppop = ppop; pop->needssl = popssl || apopssl; pop->needtls = poptls || apoptls; pop->refreshtime = 60; pop->notls = popnotls || apopnotls; mkmbox(pop, mb->path, mb->path + sizeof mb->path); mb->aux = pop; mb->sync = pop3sync; mb->close = pop3close; mb->ctl = pop3ctl; mb->addfrom = 1; return nil; }