X-Git-Url: http://git.marmaro.de/?p=mmh;a=blobdiff_plain;f=uip%2Fpopsbr.c;h=839e3d33d9891b485d8ddddbfb3e376d9d927ff4;hp=eec025dc46584ac962c72e3404a0bd52a5cdce37;hb=d8916ff5d389de5ab225cd6f40aeda1b285d0f28;hpb=7736b0a60c15cc20db0ba8c3e0fe8e11d1c78c20 diff --git a/uip/popsbr.c b/uip/popsbr.c index eec025d..839e3d3 100644 --- a/uip/popsbr.c +++ b/uip/popsbr.c @@ -1,14 +1,15 @@ - /* * popsbr.c -- POP client subroutines * * $Id$ + * + * This code is Copyright (c) 2002, by the authors of nmh. See the + * COPYRIGHT file in the root directory of the nmh distribution for + * complete copyright information. */ #include - -extern int client(char *args, char *protocol, char *service, int rproto, - char *response, int len_response); +#include #if defined(NNTP) && !defined(PSHSBR) # undef NNTP @@ -22,6 +23,11 @@ extern int client(char *args, char *protocol, char *service, int rproto, # include #endif +#ifdef CYRUS_SASL +# include +# include +#endif /* CYRUS_SASL */ + #include #include #include @@ -53,6 +59,32 @@ static char xtnd_name[512]; /* INCREDIBLE HACK!! */ # endif #endif /* NNTP */ +#ifdef CYRUS_SASL +static sasl_conn_t *conn; /* SASL connection state */ +static int sasl_complete = 0; /* Has sasl authentication succeeded? */ +static int maxoutbuf; /* Maximum output buffer size */ +static sasl_ssf_t sasl_ssf = 0; /* Security strength factor */ +static int sasl_get_user(void *, int, const char **, unsigned *); +static int sasl_get_pass(sasl_conn_t *, void *, int, sasl_secret_t **); +struct pass_context { + char *user; + char *host; +}; + +static sasl_callback_t callbacks[] = { + { SASL_CB_USER, sasl_get_user, NULL }, +#define POP_SASL_CB_N_USER 0 + { SASL_CB_PASS, sasl_get_pass, NULL }, +#define POP_SASL_CB_N_PASS 1 + { SASL_CB_LOG, NULL, NULL }, + { SASL_CB_LIST_END, NULL, NULL }, + +#define SASL_BUFFER_SIZE 262144 +}; +#else /* CYRUS_SASL */ +# define sasl_fgetc fgetc +#endif /* CYRUS_SASL */ + /* * static prototypes */ @@ -66,9 +98,14 @@ static int command(const char *, ...); static int multiline(void); #endif -static int traverse (int (*)(), const char *, ...); +#ifdef CYRUS_SASL +static int pop_auth_sasl(char *, char *, char *); +static int sasl_fgetc(FILE *); +#endif /* CYRUS_SASL */ + +static int traverse (int (*)(char *), const char *, ...); static int vcommand(const char *, va_list); -static int getline (char *, int, FILE *); +static int sasl_getline (char *, int, FILE *); static int putline (char *, FILE *); @@ -89,7 +126,7 @@ pop_auth (char *user, char *pass) return NULL; } - *++lp = NULL; + *(++lp) = '\0'; snprintf (buffer, sizeof(buffer), "%s%s", cp, pass); MD5Init (&mdContext); @@ -110,15 +147,353 @@ pop_auth (char *user, char *pass) cp += 2; buflen -= 2; } - *cp = NULL; + *cp = '\0'; return buffer; } #endif /* !NNTP && APOP */ +#ifdef CYRUS_SASL +/* + * This function implements the AUTH command for various SASL mechanisms + * + * We do the whole SASL dialog here. If this completes, then we've + * authenticated successfully and have (possibly) negotiated a security + * layer. + */ int -pop_init (char *host, char *user, char *pass, int snoop, int rpop) +pop_auth_sasl(char *user, char *host, char *mech) +{ + int result, status, sasl_capability = 0; + unsigned int buflen, outlen; + char server_mechs[256], *buf, outbuf[BUFSIZ]; + const char *chosen_mech; + sasl_security_properties_t secprops; + struct pass_context p_context; + sasl_ssf_t *ssf; + int *moutbuf; + + /* + * First off, we're going to send the CAPA command to see if we can + * even support the AUTH command, and if we do, then we'll get a + * list of mechanisms the server supports. If we don't support + * the CAPA command, then it's unlikely that we will support + * SASL + */ + + if (command("CAPA") == NOTOK) { + snprintf(response, sizeof(response), + "The POP CAPA command failed; POP server does not " + "support SASL"); + return NOTOK; + } + + while ((status = multiline()) != DONE) + switch (status) { + case NOTOK: + return NOTOK; + break; + case DONE: /* Shouldn't be possible, but just in case */ + break; + case OK: + if (strncasecmp(response, "SASL ", 5) == 0) { + /* + * We've seen the SASL capability. Grab the mech list + */ + sasl_capability++; + strncpy(server_mechs, response + 5, sizeof(server_mechs)); + } + break; + } + + if (!sasl_capability) { + snprintf(response, sizeof(response), "POP server does not support " + "SASL"); + return NOTOK; + } + + /* + * If we received a preferred mechanism, see if the server supports it. + */ + + if (mech && stringdex(mech, server_mechs) == -1) { + snprintf(response, sizeof(response), "Requested SASL mech \"%s\" is " + "not in list of supported mechanisms:\n%s", + mech, server_mechs); + return NOTOK; + } + + /* + * Start the SASL process. First off, initialize the SASL library. + */ + + callbacks[POP_SASL_CB_N_USER].context = user; + p_context.user = user; + p_context.host = host; + callbacks[POP_SASL_CB_N_PASS].context = &p_context; + + result = sasl_client_init(callbacks); + + if (result != SASL_OK) { + snprintf(response, sizeof(response), "SASL library initialization " + "failed: %s", sasl_errstring(result, NULL, NULL)); + return NOTOK; + } + + result = sasl_client_new("pop", host, NULL, NULL, NULL, 0, &conn); + + if (result != SASL_OK) { + snprintf(response, sizeof(response), "SASL client initialization " + "failed: %s", sasl_errstring(result, NULL, NULL)); + return NOTOK; + } + + /* + * Initialize the security properties + */ + + memset(&secprops, 0, sizeof(secprops)); + secprops.maxbufsize = SASL_BUFFER_SIZE; + secprops.max_ssf = UINT_MAX; + + result = sasl_setprop(conn, SASL_SEC_PROPS, &secprops); + + if (result != SASL_OK) { + snprintf(response, sizeof(response), "SASL security property " + "initialization failed: %s", sasl_errdetail(conn)); + return NOTOK; + } + + /* + * Start the actual protocol. Feed the mech list into the library + * and get out a possible initial challenge + */ + + result = sasl_client_start(conn, + (const char *) (mech ? mech : server_mechs), + NULL, (const char **) &buf, + &buflen, &chosen_mech); + + if (result != SASL_OK && result != SASL_CONTINUE) { + snprintf(response, sizeof(response), "SASL client start failed: %s", + sasl_errdetail(conn)); + return NOTOK; + } + + if (buflen) { + status = sasl_encode64(buf, buflen, outbuf, sizeof(outbuf), NULL); + if (status != SASL_OK) { + snprintf(response, sizeof(response), "SASL base64 encode " + "failed: %s", sasl_errstring(status, NULL, NULL)); + return NOTOK; + } + + status = command("AUTH %s %s", chosen_mech, outbuf); + } else + status = command("AUTH %s", chosen_mech); + + while (result == SASL_CONTINUE) { + if (status == NOTOK) + return NOTOK; + + /* + * If we get a "+OK" prefix to our response, then we should + * exit out of this exchange now (because authenticated should + * have succeeded) + */ + + if (strncmp(response, "+OK", 3) == 0) + break; + + /* + * Otherwise, make sure the server challenge is correctly formatted + */ + + if (strncmp(response, "+ ", 2) != 0) { + command("*"); + snprintf(response, sizeof(response), + "Malformed authentication message from server"); + return NOTOK; + } + + result = sasl_decode64(response + 2, strlen(response + 2), + outbuf, sizeof(outbuf), &outlen); + + if (result != SASL_OK) { + command("*"); + snprintf(response, sizeof(response), "SASL base64 decode " + "failed: %s", sasl_errstring(result, NULL, NULL)); + return NOTOK; + } + + result = sasl_client_step(conn, outbuf, outlen, NULL, + (const char **) &buf, &buflen); + + if (result != SASL_OK && result != SASL_CONTINUE) { + command("*"); + snprintf(response, sizeof(response), "SASL client negotiaton " + "failed: %s", sasl_errdetail(conn)); + return NOTOK; + } + + status = sasl_encode64(buf, buflen, outbuf, sizeof(outbuf), NULL); + + if (status != SASL_OK) { + command("*"); + snprintf(response, sizeof(response), "SASL base64 encode " + "failed: %s", sasl_errstring(status, NULL, NULL)); + return NOTOK; + } + + status = command(outbuf); + } + + /* + * If we didn't get a positive final response, then error out + * (that probably means we failed an authorization check). + */ + + if (status != OK) + return NOTOK; + + /* + * We _should_ be okay now. Get a few properties now that negotiation + * has completed. + */ + + result = sasl_getprop(conn, SASL_MAXOUTBUF, (const void **) &moutbuf); + + if (result != SASL_OK) { + snprintf(response, sizeof(response), "Cannot retrieve SASL negotiated " + "output buffer size: %s", sasl_errdetail(conn)); + return NOTOK; + } + + maxoutbuf = *moutbuf; + + result = sasl_getprop(conn, SASL_SSF, (const void **) &ssf); + + sasl_ssf = *ssf; + + if (result != SASL_OK) { + snprintf(response, sizeof(response), "Cannot retrieve SASL negotiated " + "security strength factor: %s", sasl_errdetail(conn)); + return NOTOK; + } + + /* + * Limit this to what we can deal with. Shouldn't matter much because + * this is only outgoing data (which should be small) + */ + + if (maxoutbuf == 0 || maxoutbuf > BUFSIZ) + maxoutbuf = BUFSIZ; + + sasl_complete = 1; + + return status; +} + +/* + * Callback to return the userid sent down via the user parameter + */ + +static int +sasl_get_user(void *context, int id, const char **result, unsigned *len) +{ + char *user = (char *) context; + + if (! result || id != SASL_CB_USER) + return SASL_BADPARAM; + + *result = user; + if (len) + *len = strlen(user); + + return SASL_OK; +} + +/* + * Callback to return the password (we call ruserpass, which can get it + * out of the .netrc + */ + +static int +sasl_get_pass(sasl_conn_t *conn, void *context, int id, sasl_secret_t **psecret) +{ + struct pass_context *p_context = (struct pass_context *) context; + char *pass = NULL; + int len; + + if (! psecret || id != SASL_CB_PASS) + return SASL_BADPARAM; + + ruserpass(p_context->user, &(p_context->host), &pass); + + len = strlen(pass); + + *psecret = (sasl_secret_t *) mh_xmalloc(sizeof(sasl_secret_t) + len); + + (*psecret)->len = len; + strcpy((char *) (*psecret)->data, pass); + + return SASL_OK; +} +#endif /* CYRUS_SASL */ + + +/* + * Split string containing proxy command into an array of arguments + * suitable for passing to exec. Returned array must be freed. Shouldn't + * be possible to call this with host set to NULL. + */ +char ** +parse_proxy(char *proxy, char *host) +{ + char **pargv, **p; + int pargc = 2; + int hlen = strlen(host); + int plen = 1; + unsigned char *cur, *pro; + char *c; + + /* skip any initial space */ + for (pro = (unsigned char *) proxy; isspace(*pro); pro++) + continue; + + /* calculate required size for argument array */ + for (cur = pro; *cur; cur++) { + if (isspace(*cur) && cur[1] && !isspace(cur[1])) + plen++, pargc++; + else if (*cur == '%' && cur[1] == 'h') { + plen += hlen; + cur++; + } else if (!isspace(*cur)) + plen++; + } + + /* put together list of arguments */ + p = pargv = mh_xmalloc(pargc * sizeof(char *)); + c = *pargv = mh_xmalloc(plen * sizeof(char)); + for (cur = pro; *cur; cur++) { + if (isspace(*cur) && cur[1] && !isspace(cur[1])) { + *c++ = '\0'; + *++p = c; + } else if (*cur == '%' && cur[1] == 'h') { + strcpy (c, host); + c += hlen; + cur++; + } else if (!isspace(*cur)) + *c++ = *cur; + } + *++p = NULL; + return pargv; +} + +int +pop_init (char *host, char *user, char *pass, char *proxy, int snoop, + int rpop, int kpop, int sasl, char *mech) { int fd1, fd2; char buffer[BUFSIZ]; @@ -130,29 +505,88 @@ pop_init (char *host, char *user, char *pass, int snoop, int rpop) rpop = 0; #endif + if (proxy && *proxy) { + int pid; + int inpipe[2]; /* for reading from the server */ + int outpipe[2]; /* for sending to the server */ + + /* first give up any root priviledges we may have for rpop */ + setuid(getuid()); + + pipe(inpipe); + pipe(outpipe); + + pid=fork(); + if (pid==0) { + char **argv; + + /* in child */ + close(0); + close(1); + dup2(outpipe[0],0); /* connect read end of connection */ + dup2(inpipe[1], 1); /* connect write end of connection */ + if(inpipe[0]>1) close(inpipe[0]); + if(inpipe[1]>1) close(inpipe[1]); + if(outpipe[0]>1) close(outpipe[0]); + if(outpipe[1]>1) close(outpipe[1]); + + /* run the proxy command */ + argv=parse_proxy(proxy, host); + execvp(argv[0],argv); + + perror(argv[0]); + close(0); + close(1); + free(*argv); + free(argv); + exit(10); + } + + /* okay in the parent we do some stuff */ + close(inpipe[1]); /* child uses this */ + close(outpipe[0]); /* child uses this */ + + /* we read on fd1 */ + fd1=inpipe[0]; + + /* and write on fd2 */ + fd2=outpipe[1]; + + } else { + #ifndef NNTP -# ifndef KPOP - if ((fd1 = client (host, "tcp", POPSERVICE, rpop, response, sizeof(response))) == NOTOK) -# else /* KPOP */ - snprintf (buffer, sizeof(buffer), "%s/%s", KPOP_PRINCIPAL, POPSERVICE); - if ((fd1 = client (host, "tcp", buffer, rpop, response, sizeof(response))) == NOTOK) -# endif + if ( kpop ) { +# ifdef KPOP + snprintf (buffer, sizeof(buffer), "%s/%s", KPOP_PRINCIPAL, "kpop"); + if ((fd1 = client (host, "tcp", buffer, 0, response, sizeof(response))) == NOTOK) { + return NOTOK; + } +# else /* KPOP */ + snprintf (response, sizeof(response), "this version of nmh compiled without KPOP support"); + return NOTOK; +# endif /* KPOP */ + } else { + if ((fd1 = client (host, POPSERVICE, response, sizeof(response), snoop)) == NOTOK) { + return NOTOK; + } + } #else /* NNTP */ - if ((fd1 = client (host, "tcp", "nntp", rpop, response, sizeof(response))) == NOTOK) + if ((fd1 = client (host, "nntp", response, sizeof(response), snoop)) == NOTOK) + return NOTOK; #endif - return NOTOK; - if ((fd2 = dup (fd1)) == NOTOK) { - char *s; + if ((fd2 = dup (fd1)) == NOTOK) { + char *s; - if ((s = strerror(errno))) - snprintf (response, sizeof(response), - "unable to dup connection descriptor: %s", s); - else - snprintf (response, sizeof(response), - "unable to dup connection descriptor: unknown error"); - close (fd1); - return NOTOK; + if ((s = strerror(errno))) + snprintf (response, sizeof(response), + "unable to dup connection descriptor: %s", s); + else + snprintf (response, sizeof(response), + "unable to dup connection descriptor: unknown error"); + close (fd1); + return NOTOK; + } } #ifndef NNTP if (pop_set (fd1, fd2, snoop) == NOTOK) @@ -163,7 +597,7 @@ pop_init (char *host, char *user, char *pass, int snoop, int rpop) SIGNAL (SIGPIPE, SIG_IGN); - switch (getline (response, sizeof response, input)) { + switch (sasl_getline (response, sizeof response, input)) { case OK: if (poprint) fprintf (stderr, "<--- %s\n", response); @@ -179,6 +613,12 @@ pop_init (char *host, char *user, char *pass, int snoop, int rpop) } else # endif /* APOP */ +# ifdef CYRUS_SASL + if (sasl) { + if (pop_auth_sasl(user, host, mech) != NOTOK) + return OK; + } else +# endif /* CYRUS_SASL */ if (command ("USER %s", user) != NOTOK && command ("%s %s", rpop ? "RPOP" : (pophack++, "PASS"), pass) != NOTOK) @@ -383,7 +823,7 @@ pop_list (int msgno, int *nmsgs, int *msgs, int *bytes) int -pop_retr (int msgno, int (*action)()) +pop_retr (int msgno, int (*action)(char *)) { #ifndef NNTP return traverse (action, "RETR %d", (targ_t) msgno); @@ -394,7 +834,7 @@ pop_retr (int msgno, int (*action)()) static int -traverse (int (*action)(), const char *fmt, ...) +traverse (int (*action)(char *), const char *fmt, ...) { int result; va_list ap; @@ -455,7 +895,7 @@ pop_rset (void) int -pop_top (int msgno, int lines, int (*action)()) +pop_top (int msgno, int lines, int (*action)(char *)) { #ifndef NNTP return traverse (action, "TOP %d %d", (targ_t) msgno, (targ_t) lines); @@ -488,20 +928,20 @@ pop_xtnd (int (*action)(), char *fmt, ...) snprintf (buffer, sizeof(buffer), fmt, a, b, c, d); ap = brkstring (buffer, " ", "\n"); /* a hack, i know... */ - if (!strcasecmp(ap[0], "x-bboards")) { /* XTND "X-BBOARDS group */ + if (!mh_strcasecmp(ap[0], "x-bboards")) { /* XTND "X-BBOARDS group */ /* most of these parameters are meaningless under NNTP. * bbc.c was modified to set AKA and LEADERS as appropriate, * the rest are left blank. */ return OK; } - if (!strcasecmp (ap[0], "archive") && ap[1]) { + if (!mh_strcasecmp (ap[0], "archive") && ap[1]) { snprintf (xtnd_name, sizeof(xtnd_name), "%s", ap[1]); /* save the name */ xtnd_last = 0; xtnd_first = 1; /* setup to fail in pop_stat */ return OK; } - if (!strcasecmp (ap[0], "bboards")) { + if (!mh_strcasecmp (ap[0], "bboards")) { if (ap[1]) { /* XTND "BBOARDS group" */ snprintf (xtnd_name, sizeof(xtnd_name), "%s", ap[1]); /* save the name */ @@ -524,7 +964,7 @@ pop_xtnd (int (*action)(), char *fmt, ...) return NOTOK; /* unknown XTND command */ #endif /* NNTP */ } -#endif BPOP +#endif /* BPOP */ int @@ -542,6 +982,10 @@ pop_quit (void) int pop_done (void) { +#ifdef CYRUS_SASL + if (conn) + sasl_dispose(&conn); +#endif /* CYRUS_SASL */ fclose (input); fclose (output); @@ -573,6 +1017,10 @@ vcommand (const char *fmt, va_list ap) vsnprintf (buffer, sizeof(buffer), fmt, ap); if (poprint) { +#ifdef CYRUS_SASL + if (sasl_ssf) + fprintf(stderr, "(encrypted) "); +#endif /* CYRUS_SASL */ if (pophack) { if ((cp = strchr (buffer, ' '))) *cp = 0; @@ -588,7 +1036,12 @@ vcommand (const char *fmt, va_list ap) if (putline (buffer, output) == NOTOK) return NOTOK; - switch (getline (response, sizeof response, input)) { +#ifdef CYRUS_SASL + if (poprint && sasl_ssf) + fprintf(stderr, "(decrypted) "); +#endif /* CYRUS_SASL */ + + switch (sasl_getline (response, sizeof response, input)) { case OK: if (poprint) fprintf (stderr, "<--- %s\n", response); @@ -619,12 +1072,17 @@ multiline (void) { char buffer[BUFSIZ + TRMLEN]; - if (getline (buffer, sizeof buffer, input) != OK) + if (sasl_getline (buffer, sizeof buffer, input) != OK) return NOTOK; #ifdef DEBUG - if (poprint) + if (poprint) { +#ifdef CYRUS_SASL + if (sasl_ssf) + fprintf(stderr, "(decrypted) "); +#endif /* CYRUS_SASL */ fprintf (stderr, "<--- %s\n", response); -#endif DEBUG + } +#endif /* DEBUG */ if (strncmp (buffer, TRM, TRMLEN) == 0) { if (buffer[TRMLEN] == 0) return DONE; @@ -637,17 +1095,23 @@ multiline (void) return OK; } +/* + * Note that these functions have been modified to deal with layer encryption + * in the SASL case + */ static int -getline (char *s, int n, FILE *iop) +sasl_getline (char *s, int n, FILE *iop) { int c; char *p; p = s; - while (--n > 0 && (c = fgetc (iop)) != EOF) + while (--n > 0 && (c = sasl_fgetc (iop)) != EOF && c != -2) if ((*p++ = c) == '\n') break; + if (c == -2) + return NOTOK; if (ferror (iop) && c != EOF) { strncpy (response, "error on connection", sizeof(response)); return NOTOK; @@ -669,7 +1133,37 @@ getline (char *s, int n, FILE *iop) static int putline (char *s, FILE *iop) { - fprintf (iop, "%s\r\n", s); +#ifdef CYRUS_SASL + char outbuf[BUFSIZ], *buf; + int result; + unsigned int buflen; + + if (!sasl_complete) { +#endif /* CYRUS_SASL */ + fprintf (iop, "%s\r\n", s); +#ifdef CYRUS_SASL + } else { + /* + * Build an output buffer, encrypt it using sasl_encode, and + * squirt out the results. + */ + strncpy(outbuf, s, sizeof(outbuf) - 3); + outbuf[sizeof(outbuf) - 3] = '\0'; /* Just in case */ + strcat(outbuf, "\r\n"); + + result = sasl_encode(conn, outbuf, strlen(outbuf), + (const char **) &buf, &buflen); + + if (result != SASL_OK) { + snprintf(response, sizeof(response), "SASL encoding error: %s", + sasl_errdetail(conn)); + return NOTOK; + } + + fwrite(buf, buflen, 1, iop); + } +#endif /* CYRUS_SASL */ + fflush (iop); if (ferror (iop)) { strncpy (response, "lost connection", sizeof(response)); @@ -678,3 +1172,80 @@ putline (char *s, FILE *iop) return OK; } + +#ifdef CYRUS_SASL +/* + * Okay, our little fgetc replacement. Hopefully this is a little more + * efficient than the last one. + */ +static int +sasl_fgetc(FILE *f) +{ + static unsigned char *buffer = NULL, *ptr; + static int size = 0; + static int cnt = 0; + unsigned int retbufsize = 0; + int cc, result; + char *retbuf, tmpbuf[SASL_BUFFER_SIZE]; + + /* + * If we have some leftover data, return that + */ + + if (cnt) { + cnt--; + return (int) *ptr++; + } + + /* + * Otherwise, fill our buffer until we have some data to return. + */ + + while (retbufsize == 0) { + + cc = read(fileno(f), tmpbuf, sizeof(tmpbuf)); + + if (cc == 0) + return EOF; + + if (cc < 0) { + snprintf(response, sizeof(response), "Error during read from " + "network: %s", strerror(errno)); + return -2; + } + + /* + * We're not allowed to call sasl_decode until sasl_complete is + * true, so we do these gyrations ... + */ + + if (!sasl_complete) { + + retbuf = tmpbuf; + retbufsize = cc; + + } else { + + result = sasl_decode(conn, tmpbuf, cc, + (const char **) &retbuf, &retbufsize); + + if (result != SASL_OK) { + snprintf(response, sizeof(response), "Error during SASL " + "decoding: %s", sasl_errdetail(conn)); + return -2; + } + } + } + + if (retbufsize > size) { + buffer = mh_xrealloc(buffer, retbufsize); + size = retbufsize; + } + + memcpy(buffer, retbuf, retbufsize); + ptr = buffer + 1; + cnt = retbufsize - 1; + + return (int) buffer[0]; +} +#endif /* CYRUS_SASL */