diff options
Diffstat (limited to 'contrib/sendmail/src/tls.c')
| -rw-r--r-- | contrib/sendmail/src/tls.c | 1469 |
1 files changed, 1469 insertions, 0 deletions
diff --git a/contrib/sendmail/src/tls.c b/contrib/sendmail/src/tls.c new file mode 100644 index 0000000..2eb0047 --- /dev/null +++ b/contrib/sendmail/src/tls.c @@ -0,0 +1,1469 @@ +/* + * Copyright (c) 2000-2001 Sendmail, Inc. and its suppliers. + * All rights reserved. + * + * By using this file, you agree to the terms and conditions set + * forth in the LICENSE file which can be found at the top level of + * the sendmail distribution. + * + */ + +#include <sendmail.h> + +SM_RCSID("@(#)$Id: tls.c,v 8.75 2001/09/11 04:05:17 gshapiro Exp $") + +#if STARTTLS +# include <openssl/err.h> +# include <openssl/bio.h> +# include <openssl/pem.h> +# ifndef HASURANDOMDEV +# include <openssl/rand.h> +# endif /* ! HASURANDOMDEV */ +# if SM_CONF_SHM +# include <sm/shm.h> +# endif /* SM_CONF_SHM */ +# if !TLS_NO_RSA +static RSA *rsa_tmp = NULL; /* temporary RSA key */ +static RSA *tmp_rsa_key __P((SSL *, int, int)); +# endif /* !TLS_NO_RSA */ +static int tls_verify_cb __P((X509_STORE_CTX *)); + +static void apps_ssl_info_cb __P((SSL *, int , int)); + +# if !NO_DH +static DH *get_dh512 __P((void)); + +static unsigned char dh512_p[] = +{ + 0xDA,0x58,0x3C,0x16,0xD9,0x85,0x22,0x89,0xD0,0xE4,0xAF,0x75, + 0x6F,0x4C,0xCA,0x92,0xDD,0x4B,0xE5,0x33,0xB8,0x04,0xFB,0x0F, + 0xED,0x94,0xEF,0x9C,0x8A,0x44,0x03,0xED,0x57,0x46,0x50,0xD3, + 0x69,0x99,0xDB,0x29,0xD7,0x76,0x27,0x6B,0xA2,0xD3,0xD4,0x12, + 0xE2,0x18,0xF4,0xDD,0x1E,0x08,0x4C,0xF6,0xD8,0x00,0x3E,0x7C, + 0x47,0x74,0xE8,0x33 +}; +static unsigned char dh512_g[] = +{ + 0x02 +}; + +static DH * +get_dh512() +{ + DH *dh = NULL; + + if ((dh = DH_new()) == NULL) + return NULL; + dh->p = BN_bin2bn(dh512_p, sizeof(dh512_p), NULL); + dh->g = BN_bin2bn(dh512_g, sizeof(dh512_g), NULL); + if ((dh->p == NULL) || (dh->g == NULL)) + return NULL; + return dh; +} +# endif /* !NO_DH */ + + +/* +** TLS_RAND_INIT -- initialize STARTTLS random generator +** +** Parameters: +** randfile -- name of file with random data +** logl -- loglevel +** +** Returns: +** success/failure +** +** Side Effects: +** initializes PRNG for tls library. +*/ + +# define MIN_RAND_BYTES 128 /* 1024 bits */ + +# define RF_OK 0 /* randfile OK */ +# define RF_MISS 1 /* randfile == NULL || *randfile == '\0' */ +# define RF_UNKNOWN 2 /* unknown prefix for randfile */ + +# define RI_NONE 0 /* no init yet */ +# define RI_SUCCESS 1 /* init was successful */ +# define RI_FAIL 2 /* init failed */ + +static bool tls_rand_init __P((char *, int)); + +static bool +tls_rand_init(randfile, logl) + char *randfile; + int logl; +{ +# ifndef HASURANDOMDEV + /* not required if /dev/urandom exists, OpenSSL does it internally */ + + bool ok; + int randdef; + static int done = RI_NONE; + + /* + ** initialize PRNG + */ + + /* did we try this before? if yes: return old value */ + if (done != RI_NONE) + return done == RI_SUCCESS; + + /* set default values */ + ok = false; + done = RI_FAIL; + randdef = (randfile == NULL || *randfile == '\0') ? RF_MISS : RF_OK; +# if EGD + if (randdef == RF_OK && sm_strncasecmp(randfile, "egd:", 4) == 0) + { + randfile += 4; + if (RAND_egd(randfile) < 0) + { + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS: RAND_egd(%s) failed: random number generator not seeded", + randfile); + } + else + ok = true; + } + else +# endif /* EGD */ + if (randdef == RF_OK && sm_strncasecmp(randfile, "file:", 5) == 0) + { + int fd; + long sff; + struct stat st; + + randfile += 5; + sff = SFF_SAFEDIRPATH | SFF_NOWLINK + | SFF_NOGWFILES | SFF_NOWWFILES + | SFF_NOGRFILES | SFF_NOWRFILES + | SFF_MUSTOWN | SFF_ROOTOK | SFF_OPENASROOT; + if ((fd = safeopen(randfile, O_RDONLY, 0, sff)) >= 0) + { + if (fstat(fd, &st) < 0) + { + if (LogLevel > logl) + sm_syslog(LOG_ERR, NOQID, + "STARTTLS: can't fstat(%s)", + randfile); + } + else + { + bool use, problem; + + use = true; + problem = false; + + /* max. age of file: 10 minutes */ + if (st.st_mtime + 600 < curtime()) + { + use = bitnset(DBS_INSUFFICIENTENTROPY, + DontBlameSendmail); + problem = true; + if (LogLevel > logl) + sm_syslog(LOG_ERR, NOQID, + "STARTTLS: RandFile %s too old: %s", + randfile, + use ? "unsafe" : + "unusable"); + } + if (use && st.st_size < MIN_RAND_BYTES) + { + use = bitnset(DBS_INSUFFICIENTENTROPY, + DontBlameSendmail); + problem = true; + if (LogLevel > logl) + sm_syslog(LOG_ERR, NOQID, + "STARTTLS: size(%s) < %d: %s", + randfile, + MIN_RAND_BYTES, + use ? "unsafe" : + "unusable"); + } + if (use) + ok = RAND_load_file(randfile, -1) >= + MIN_RAND_BYTES; + if (use && !ok) + { + if (LogLevel > logl) + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS: RAND_load_file(%s) failed: random number generator not seeded", + randfile); + } + if (problem) + ok = false; + } + if (ok || bitnset(DBS_INSUFFICIENTENTROPY, + DontBlameSendmail)) + { + /* add this even if fstat() failed */ + RAND_seed((void *) &st, sizeof st); + } + (void) close(fd); + } + else + { + if (LogLevel > logl) + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS: Warning: safeopen(%s) failed", + randfile); + } + } + else if (randdef == RF_OK) + { + if (LogLevel > logl) + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS: Error: no proper random file definition %s", + randfile); + randdef = RF_UNKNOWN; + } + if (randdef == RF_MISS) + { + if (LogLevel > logl) + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS: Error: missing random file definition"); + } + if (!ok && bitnset(DBS_INSUFFICIENTENTROPY, DontBlameSendmail)) + { + int i; + long r; + unsigned char buf[MIN_RAND_BYTES]; + + /* assert((MIN_RAND_BYTES % sizeof(long)) == 0); */ + for (i = 0; i <= sizeof(buf) - sizeof(long); i += sizeof(long)) + { + r = get_random(); + (void) memcpy(buf + i, (void *) &r, sizeof(long)); + } + RAND_seed(buf, sizeof buf); + if (LogLevel > logl) + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS: Warning: random number generator not properly seeded"); + ok = true; + } + done = ok ? RI_SUCCESS : RI_FAIL; + return ok; +# else /* ! HASURANDOMDEV */ + return true; +# endif /* ! HASURANDOMDEV */ +} +/* +** INIT_TLS_LIBRARY -- Calls functions which setup TLS library for global use. +** +** Parameters: +** none. +** +** Returns: +** succeeded? +*/ + +bool +init_tls_library() +{ + /* basic TLS initialization, ignore result for now */ + SSL_library_init(); + SSL_load_error_strings(); +# if 0 + /* this is currently a macro for SSL_library_init */ + SSLeay_add_ssl_algorithms(); +# endif /* 0 */ + + return tls_rand_init(RandFile, 7); +} +/* +** TLS_SET_VERIFY -- request client certificate? +** +** Parameters: +** ctx -- TLS context +** ssl -- TLS structure +** vrfy -- require certificate? +** +** Returns: +** none. +** +** Side Effects: +** Sets verification state for TLS +** +# if TLS_VRFY_PER_CTX +** Notice: +** This is per TLS context, not per TLS structure; +** the former is global, the latter per connection. +** It would be nice to do this per connection, but this +** doesn't work in the current TLS libraries :-( +# endif * TLS_VRFY_PER_CTX * +*/ + +void +tls_set_verify(ctx, ssl, vrfy) + SSL_CTX *ctx; + SSL *ssl; + bool vrfy; +{ +# if !TLS_VRFY_PER_CTX + SSL_set_verify(ssl, vrfy ? SSL_VERIFY_PEER : SSL_VERIFY_NONE, NULL); +# else /* !TLS_VRFY_PER_CTX */ + SSL_CTX_set_verify(ctx, vrfy ? SSL_VERIFY_PEER : SSL_VERIFY_NONE, + NULL); +# endif /* !TLS_VRFY_PER_CTX */ +} + +/* +** status in initialization +** these flags keep track of the status of the initialization +** i.e., whether a file exists (_EX) and whether it can be used (_OK) +** [due to permissions] +*/ + +# define TLS_S_NONE 0x00000000 /* none yet */ +# define TLS_S_CERT_EX 0x00000001 /* CERT file exists */ +# define TLS_S_CERT_OK 0x00000002 /* CERT file is ok */ +# define TLS_S_KEY_EX 0x00000004 /* KEY file exists */ +# define TLS_S_KEY_OK 0x00000008 /* KEY file is ok */ +# define TLS_S_CERTP_EX 0x00000010 /* CA CERT PATH exists */ +# define TLS_S_CERTP_OK 0x00000020 /* CA CERT PATH is ok */ +# define TLS_S_CERTF_EX 0x00000040 /* CA CERT FILE exists */ +# define TLS_S_CERTF_OK 0x00000080 /* CA CERT FILE is ok */ + +# if _FFR_TLS_1 +# define TLS_S_CERT2_EX 0x00001000 /* 2nd CERT file exists */ +# define TLS_S_CERT2_OK 0x00002000 /* 2nd CERT file is ok */ +# define TLS_S_KEY2_EX 0x00004000 /* 2nd KEY file exists */ +# define TLS_S_KEY2_OK 0x00008000 /* 2nd KEY file is ok */ +# endif /* _FFR_TLS_1 */ + +# define TLS_S_DH_OK 0x00200000 /* DH cert is ok */ +# define TLS_S_DHPAR_EX 0x00400000 /* DH param file exists */ +# define TLS_S_DHPAR_OK 0x00800000 /* DH param file is ok to use */ + +/* +** TLS_OK_F -- can var be an absolute filename? +** +** Parameters: +** var -- filename +** fn -- what is the filename used for? +** srv -- server side? +** +** Returns: +** ok? +*/ + +static bool +tls_ok_f(var, fn, srv) + char *var; + char *fn; + bool srv; +{ + /* must be absolute pathname */ + if (var != NULL && *var == '/') + return true; + if (LogLevel > 12) + sm_syslog(LOG_WARNING, NOQID, "STARTTLS: %s%s missing", + srv ? "Server" : "Client", fn); + return false; +} +/* +** TLS_SAFE_F -- is a file safe to use? +** +** Parameters: +** var -- filename +** sff -- flags for safefile() +** srv -- server side? +** +** Returns: +** ok? +*/ + +static bool +tls_safe_f(var, sff, srv) + char *var; + long sff; + bool srv; +{ + int ret; + + if ((ret = safefile(var, RunAsUid, RunAsGid, RunAsUserName, sff, + S_IRUSR, NULL)) == 0) + return true; + if (LogLevel > 7) + sm_syslog(LOG_WARNING, NOQID, "STARTTLS=%s: file %s unsafe: %s", + srv ? "server" : "client", var, sm_errstring(ret)); + return false; +} + +/* +** TLS_OK_F -- macro to simplify calls to tls_ok_f +** +** Parameters: +** var -- filename +** fn -- what is the filename used for? +** req -- is the file required? +** st -- status bit to set if ok +** srv -- server side? +** +** Side Effects: +** uses r, ok; may change ok and status. +** +*/ + +# define TLS_OK_F(var, fn, req, st, srv) if (ok) \ + { \ + r = tls_ok_f(var, fn, srv); \ + if (r) \ + status |= st; \ + else if (req) \ + ok = false; \ + } + +/* +** TLS_UNR -- macro to return whether a file should be unreadable +** +** Parameters: +** bit -- flag to test +** req -- flags +** +** Returns: +** 0/SFF_NORFILES +*/ +# define TLS_UNR(bit, req) (bitset(bit, req) ? SFF_NORFILES : 0) +# define TLS_OUNR(bit, req) (bitset(bit, req) ? SFF_NOWRFILES : 0) +# define TLS_KEYSFF(req) \ + (bitnset(DBS_GROUPREADABLEKEYFILE, DontBlameSendmail) ? \ + TLS_OUNR(TLS_I_KEY_OUNR, req) : \ + TLS_UNR(TLS_I_KEY_UNR, req)) + +/* +** TLS_SAFE_F -- macro to simplify calls to tls_safe_f +** +** Parameters: +** var -- filename +** sff -- flags for safefile() +** req -- is the file required? +** ex -- does the file exist? +** st -- status bit to set if ok +** srv -- server side? +** +** Side Effects: +** uses r, ok, ex; may change ok and status. +** +*/ + +# define TLS_SAFE_F(var, sff, req, ex, st, srv) if (ex && ok) \ + { \ + r = tls_safe_f(var, sff, srv); \ + if (r) \ + status |= st; \ + else if (req) \ + ok = false; \ + } + +/* +** INITTLS -- initialize TLS +** +** Parameters: +** ctx -- pointer to context +** req -- requirements for initialization (see sendmail.h) +** srv -- server side? +** certfile -- filename of certificate +** keyfile -- filename of private key +** cacertpath -- path to CAs +** cacertfile -- file with CA(s) +** dhparam -- parameters for DH +** +** Returns: +** succeeded? +*/ + +bool +inittls(ctx, req, srv, certfile, keyfile, cacertpath, cacertfile, dhparam) + SSL_CTX **ctx; + unsigned long req; + bool srv; + char *certfile, *keyfile, *cacertpath, *cacertfile, *dhparam; +{ +# if !NO_DH + static DH *dh = NULL; +# endif /* !NO_DH */ + int r; + bool ok; + long sff, status; + char *who; +# if _FFR_TLS_1 + char *cf2, *kf2; +# endif /* _FFR_TLS_1 */ +# if SM_CONF_SHM + extern int ShmId; +# endif /* SM_CONF_SHM */ + + status = TLS_S_NONE; + who = srv ? "server" : "client"; + if (ctx == NULL) + syserr("STARTTLS=%s, inittls: ctx == NULL", who); + + /* already initialized? (we could re-init...) */ + if (*ctx != NULL) + return true; + ok = true; + +# if _FFR_TLS_1 + /* + ** look for a second filename: it must be separated by a ',' + ** no blanks allowed (they won't be skipped). + ** we change a global variable here! this change will be undone + ** before return from the function but only if it returns true. + ** this isn't a problem since in a failure case this function + ** won't be called again with the same (overwritten) values. + ** otherwise each return must be replaced with a goto endinittls. + */ + + cf2 = NULL; + kf2 = NULL; + if (certfile != NULL && (cf2 = strchr(certfile, ',')) != NULL) + { + *cf2++ = '\0'; + if (keyfile != NULL && (kf2 = strchr(keyfile, ',')) != NULL) + *kf2++ = '\0'; + } +# endif /* _FFR_TLS_1 */ + + /* + ** Check whether files/paths are defined + */ + + TLS_OK_F(certfile, "CertFile", bitset(TLS_I_CERT_EX, req), + TLS_S_CERT_EX, srv); + TLS_OK_F(keyfile, "KeyFile", bitset(TLS_I_KEY_EX, req), + TLS_S_KEY_EX, srv); + TLS_OK_F(cacertpath, "CACERTPath", bitset(TLS_I_CERTP_EX, req), + TLS_S_CERTP_EX, srv); + TLS_OK_F(cacertfile, "CACERTFile", bitset(TLS_I_CERTF_EX, req), + TLS_S_CERTF_EX, srv); + +# if _FFR_TLS_1 + /* + ** if the second file is specified it must exist + ** XXX: it is possible here to define only one of those files + */ + + if (cf2 != NULL) + { + TLS_OK_F(cf2, "CertFile", bitset(TLS_I_CERT_EX, req), + TLS_S_CERT2_EX, srv); + } + if (kf2 != NULL) + { + TLS_OK_F(kf2, "KeyFile", bitset(TLS_I_KEY_EX, req), + TLS_S_KEY2_EX, srv); + } +# endif /* _FFR_TLS_1 */ + + /* + ** valid values for dhparam are (only the first char is checked) + ** none no parameters: don't use DH + ** 512 generate 512 bit parameters (fixed) + ** 1024 generate 1024 bit parameters + ** /file/name read parameters from /file/name + ** default is: 1024 for server, 512 for client (OK? XXX) + */ + + if (bitset(TLS_I_TRY_DH, req)) + { + if (dhparam != NULL) + { + char c = *dhparam; + + if (c == '1') + req |= TLS_I_DH1024; + else if (c == '5') + req |= TLS_I_DH512; + else if (c != 'n' && c != 'N' && c != '/') + { + if (LogLevel > 12) + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS=%s, error: illegal value '%s' for DHParam", + who, dhparam); + dhparam = NULL; + } + } + if (dhparam == NULL) + dhparam = srv ? "1" : "5"; + else if (*dhparam == '/') + { + TLS_OK_F(dhparam, "DHParameters", + bitset(TLS_I_DHPAR_EX, req), + TLS_S_DHPAR_EX, srv); + } + } + if (!ok) + return ok; + + /* certfile etc. must be "safe". */ + sff = SFF_REGONLY | SFF_SAFEDIRPATH | SFF_NOWLINK + | SFF_NOGWFILES | SFF_NOWWFILES + | SFF_MUSTOWN | SFF_ROOTOK | SFF_OPENASROOT; + if (DontLockReadFiles) + sff |= SFF_NOLOCK; + + TLS_SAFE_F(certfile, sff | TLS_UNR(TLS_I_CERT_UNR, req), + bitset(TLS_I_CERT_EX, req), + bitset(TLS_S_CERT_EX, status), TLS_S_CERT_OK, srv); + TLS_SAFE_F(keyfile, sff | TLS_KEYSFF(req), + bitset(TLS_I_KEY_EX, req), + bitset(TLS_S_KEY_EX, status), TLS_S_KEY_OK, srv); + TLS_SAFE_F(cacertfile, sff | TLS_UNR(TLS_I_CERTF_UNR, req), + bitset(TLS_I_CERTF_EX, req), + bitset(TLS_S_CERTF_EX, status), TLS_S_CERTF_OK, srv); + TLS_SAFE_F(dhparam, sff | TLS_UNR(TLS_I_DHPAR_UNR, req), + bitset(TLS_I_DHPAR_EX, req), + bitset(TLS_S_DHPAR_EX, status), TLS_S_DHPAR_OK, srv); + if (!ok) + return ok; +# if _FFR_TLS_1 + if (cf2 != NULL) + { + TLS_SAFE_F(cf2, sff | TLS_UNR(TLS_I_CERT_UNR, req), + bitset(TLS_I_CERT_EX, req), + bitset(TLS_S_CERT2_EX, status), TLS_S_CERT2_OK, srv); + } + if (kf2 != NULL) + { + TLS_SAFE_F(kf2, sff | TLS_KEYSFF(req), + bitset(TLS_I_KEY_EX, req), + bitset(TLS_S_KEY2_EX, status), TLS_S_KEY2_OK, srv); + } +# endif /* _FFR_TLS_1 */ + + /* create a method and a new context */ + if ((*ctx = SSL_CTX_new(srv ? SSLv23_server_method() : + SSLv23_client_method())) == NULL) + { + if (LogLevel > 7) + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS=%s, error: SSL_CTX_new(SSLv23_%s_method()) failed", + who, who); + if (LogLevel > 9) + tlslogerr(who); + return false; + } + +# if TLS_NO_RSA + /* turn off backward compatibility, required for no-rsa */ + SSL_CTX_set_options(*ctx, SSL_OP_NO_SSLv2); +# endif /* TLS_NO_RSA */ + + +# if !TLS_NO_RSA + /* + ** Create a temporary RSA key + ** XXX Maybe we shouldn't create this always (even though it + ** is only at startup). + ** It is a time-consuming operation and it is not always necessary. + ** maybe we should do it only on demand... + */ + + if (bitset(TLS_I_RSA_TMP, req) +# if SM_CONF_SHM + && ShmId != SM_SHM_NO_ID && + (rsa_tmp = RSA_generate_key(RSA_KEYLENGTH, RSA_F4, NULL, + NULL)) == NULL +# else /* SM_CONF_SHM */ + && 0 /* no shared memory: no need to generate key now */ +# endif /* SM_CONF_SHM */ + ) + { + if (LogLevel > 7) + { + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS=%s, error: RSA_generate_key failed", + who); + if (LogLevel > 9) + tlslogerr(who); + } + return false; + } +# endif /* !TLS_NO_RSA */ + + /* + ** load private key + ** XXX change this for DSA-only version + */ + + if (bitset(TLS_S_KEY_OK, status) && + SSL_CTX_use_PrivateKey_file(*ctx, keyfile, + SSL_FILETYPE_PEM) <= 0) + { + if (LogLevel > 7) + { + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS=%s, error: SSL_CTX_use_PrivateKey_file(%s) failed", + who, keyfile); + if (LogLevel > 9) + tlslogerr(who); + } + if (bitset(TLS_I_USE_KEY, req)) + return false; + } + + /* get the certificate file */ + if (bitset(TLS_S_CERT_OK, status) && + SSL_CTX_use_certificate_file(*ctx, certfile, + SSL_FILETYPE_PEM) <= 0) + { + if (LogLevel > 7) + { + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS=%s, error: SSL_CTX_use_certificate_file(%s) failed", + who, certfile); + if (LogLevel > 9) + tlslogerr(who); + } + if (bitset(TLS_I_USE_CERT, req)) + return false; + } + + /* check the private key */ + if (bitset(TLS_S_KEY_OK, status) && + (r = SSL_CTX_check_private_key(*ctx)) <= 0) + { + /* Private key does not match the certificate public key */ + if (LogLevel > 5) + { + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS=%s, error: SSL_CTX_check_private_key failed(%s): %d", + who, keyfile, r); + if (LogLevel > 9) + tlslogerr(who); + } + if (bitset(TLS_I_USE_KEY, req)) + return false; + } + +# if _FFR_TLS_1 + /* XXX this code is pretty much duplicated from above! */ + + /* load private key */ + if (bitset(TLS_S_KEY2_OK, status) && + SSL_CTX_use_PrivateKey_file(*ctx, kf2, SSL_FILETYPE_PEM) <= 0) + { + if (LogLevel > 7) + { + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS=%s, error: SSL_CTX_use_PrivateKey_file(%s) failed", + who, kf2); + if (LogLevel > 9) + tlslogerr(who); + } + } + + /* get the certificate file */ + if (bitset(TLS_S_CERT2_OK, status) && + SSL_CTX_use_certificate_file(*ctx, cf2, SSL_FILETYPE_PEM) <= 0) + { + if (LogLevel > 7) + { + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS=%s, error: SSL_CTX_use_certificate_file(%s) failed", + who, cf2); + if (LogLevel > 9) + tlslogerr(who); + } + } + + /* also check the private key */ + if (bitset(TLS_S_KEY2_OK, status) && + (r = SSL_CTX_check_private_key(*ctx)) <= 0) + { + /* Private key does not match the certificate public key */ + if (LogLevel > 5) + { + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS=%s, error: SSL_CTX_check_private_key 2 failed: %d", + who, r); + if (LogLevel > 9) + tlslogerr(who); + } + } +# endif /* _FFR_TLS_1 */ + + /* SSL_CTX_set_quiet_shutdown(*ctx, 1); violation of standard? */ + SSL_CTX_set_options(*ctx, SSL_OP_ALL); /* XXX bug compatibility? */ + +# if !NO_DH + /* Diffie-Hellman initialization */ + if (bitset(TLS_I_TRY_DH, req)) + { + if (bitset(TLS_S_DHPAR_OK, status)) + { + BIO *bio; + + if ((bio = BIO_new_file(dhparam, "r")) != NULL) + { + dh = PEM_read_bio_DHparams(bio, NULL, NULL, NULL); + BIO_free(bio); + if (dh == NULL && LogLevel > 7) + { + unsigned long err; + + err = ERR_get_error(); + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS=%s, error: cannot read DH parameters(%s): %s", + who, dhparam, + ERR_error_string(err, NULL)); + if (LogLevel > 9) + tlslogerr(who); + } + } + else + { + if (LogLevel > 5) + { + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS=%s, error: BIO_new_file(%s) failed", + who, dhparam); + if (LogLevel > 9) + tlslogerr(who); + } + } + } + if (dh == NULL && bitset(TLS_I_DH1024, req)) + { + DSA *dsa; + + /* this takes a while! (7-130s on a 450MHz AMD K6-2) */ + dsa = DSA_generate_parameters(1024, NULL, 0, NULL, + NULL, 0, NULL); + dh = DSA_dup_DH(dsa); + DSA_free(dsa); + } + else + if (dh == NULL && bitset(TLS_I_DH512, req)) + dh = get_dh512(); + + if (dh == NULL) + { + if (LogLevel > 9) + { + unsigned long err; + + err = ERR_get_error(); + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS=%s, error: cannot read or set DH parameters(%s): %s", + who, dhparam, + ERR_error_string(err, NULL)); + } + if (bitset(TLS_I_REQ_DH, req)) + return false; + } + else + { + SSL_CTX_set_tmp_dh(*ctx, dh); + + /* important to avoid small subgroup attacks */ + SSL_CTX_set_options(*ctx, SSL_OP_SINGLE_DH_USE); + if (LogLevel > 13) + sm_syslog(LOG_INFO, NOQID, + "STARTTLS=%s, Diffie-Hellman init, key=%d bit (%c)", + who, 8 * DH_size(dh), *dhparam); + DH_free(dh); + } + } +# endif /* !NO_DH */ + + + /* XXX do we need this cache here? */ + if (bitset(TLS_I_CACHE, req)) + SSL_CTX_sess_set_cache_size(*ctx, 128); + /* timeout? SSL_CTX_set_timeout(*ctx, TimeOut...); */ + + /* load certificate locations and default CA paths */ + if (bitset(TLS_S_CERTP_EX, status) && bitset(TLS_S_CERTF_EX, status)) + { + if ((r = SSL_CTX_load_verify_locations(*ctx, cacertfile, + cacertpath)) == 1) + { +# if !TLS_NO_RSA + if (bitset(TLS_I_RSA_TMP, req)) + SSL_CTX_set_tmp_rsa_callback(*ctx, tmp_rsa_key); +# endif /* !TLS_NO_RSA */ + + /* + ** We have to install our own verify callback: + ** SSL_VERIFY_PEER requests a client cert but even + ** though *FAIL_IF* isn't set, the connection + ** will be aborted if the client presents a cert + ** that is not "liked" (can't be verified?) by + ** the TLS library :-( + */ + + /* + ** XXX currently we could call tls_set_verify() + ** but we hope that that function will later on + ** only set the mode per connection. + */ + SSL_CTX_set_verify(*ctx, + bitset(TLS_I_NO_VRFY, req) ? SSL_VERIFY_NONE + : SSL_VERIFY_PEER, + NULL); + + /* install verify callback */ + SSL_CTX_set_cert_verify_callback(*ctx, tls_verify_cb, + NULL); + SSL_CTX_set_client_CA_list(*ctx, + SSL_load_client_CA_file(cacertfile)); + } + else + { + /* + ** can't load CA data; do we care? + ** the data is necessary to authenticate the client, + ** which in turn would be necessary + ** if we want to allow relaying based on it. + */ + if (LogLevel > 5) + { + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS=%s, error: load verify locs %s, %s failed: %d", + who, cacertpath, cacertfile, r); + if (LogLevel > 9) + tlslogerr(who); + } + if (bitset(TLS_I_VRFY_LOC, req)) + return false; + } + } + + /* XXX: make this dependent on an option? */ + if (tTd(96, 9)) + SSL_CTX_set_info_callback(*ctx, apps_ssl_info_cb); + +# if _FFR_TLS_1 + /* install our own cipher list */ + if (CipherList != NULL && *CipherList != '\0') + { + if (SSL_CTX_set_cipher_list(*ctx, CipherList) <= 0) + { + if (LogLevel > 7) + { + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS=%s, error: SSL_CTX_set_cipher_list(%s) failed, list ignored", + who, CipherList); + + if (LogLevel > 9) + tlslogerr(who); + } + /* failure if setting to this list is required? */ + } + } +# endif /* _FFR_TLS_1 */ + if (LogLevel > 12) + sm_syslog(LOG_INFO, NOQID, "STARTTLS=%s, init=%d", who, ok); + +# if _FFR_TLS_1 +# if 0 + /* + ** this label is required if we want to have a "clean" exit + ** see the comments above at the initialization of cf2 + */ + + endinittls: +# endif /* 0 */ + + /* undo damage to global variables */ + if (cf2 != NULL) + *--cf2 = ','; + if (kf2 != NULL) + *--kf2 = ','; +# endif /* _FFR_TLS_1 */ + + return ok; +} +/* +** TLS_GET_INFO -- get information about TLS connection +** +** Parameters: +** ssl -- TLS connection structure +** srv -- server or client +** host -- hostname of other side +** mac -- macro storage +** certreq -- did we ask for a cert? +** +** Returns: +** result of authentication. +** +** Side Effects: +** sets macros: {cipher}, {tls_version}, {verify}, +** {cipher_bits}, {alg_bits}, {cert}, {cert_subject}, +** {cert_issuer}, {cn_subject}, {cn_issuer} +*/ + +int +tls_get_info(ssl, srv, host, mac, certreq) + SSL *ssl; + bool srv; + char *host; + MACROS_T *mac; + bool certreq; +{ + SSL_CIPHER *c; + int b, r; + char *s, *who; + char bitstr[16]; + X509 *cert; + + c = SSL_get_current_cipher(ssl); + + /* cast is just workaround for compiler warning */ + macdefine(mac, A_TEMP, macid("{cipher}"), + (char *) SSL_CIPHER_get_name(c)); + b = SSL_CIPHER_get_bits(c, &r); + (void) sm_snprintf(bitstr, sizeof bitstr, "%d", b); + macdefine(mac, A_TEMP, macid("{cipher_bits}"), bitstr); + (void) sm_snprintf(bitstr, sizeof bitstr, "%d", r); + macdefine(mac, A_TEMP, macid("{alg_bits}"), bitstr); + s = SSL_CIPHER_get_version(c); + if (s == NULL) + s = "UNKNOWN"; + macdefine(mac, A_TEMP, macid("{tls_version}"), s); + + who = srv ? "server" : "client"; + cert = SSL_get_peer_certificate(ssl); + if (LogLevel > 14) + sm_syslog(LOG_INFO, NOQID, + "STARTTLS=%s, get_verify: %ld get_peer: 0x%lx", + who, SSL_get_verify_result(ssl), + (unsigned long) cert); + if (cert != NULL) + { + unsigned int n; + unsigned char md[EVP_MAX_MD_SIZE]; + char buf[MAXNAME]; + + X509_NAME_oneline(X509_get_subject_name(cert), + buf, sizeof buf); + macdefine(mac, A_TEMP, macid("{cert_subject}"), + xtextify(buf, "<>\")")); + X509_NAME_oneline(X509_get_issuer_name(cert), + buf, sizeof buf); + macdefine(mac, A_TEMP, macid("{cert_issuer}"), + xtextify(buf, "<>\")")); + X509_NAME_get_text_by_NID(X509_get_subject_name(cert), + NID_commonName, buf, sizeof buf); + macdefine(mac, A_TEMP, macid("{cn_subject}"), + xtextify(buf, "<>\")")); + X509_NAME_get_text_by_NID(X509_get_issuer_name(cert), + NID_commonName, buf, sizeof buf); + macdefine(mac, A_TEMP, macid("{cn_issuer}"), + xtextify(buf, "<>\")")); + if (X509_digest(cert, EVP_md5(), md, &n)) + { + char md5h[EVP_MAX_MD_SIZE * 3]; + static const char hexcodes[] = "0123456789ABCDEF"; + + SM_ASSERT((n * 3) + 2 < sizeof(md5h)); + for (r = 0; r < (int) n; r++) + { + md5h[r * 3] = hexcodes[(md[r] & 0xf0) >> 4]; + md5h[(r * 3) + 1] = hexcodes[(md[r] & 0x0f)]; + md5h[(r * 3) + 2] = ':'; + } + md5h[(n * 3) - 1] = '\0'; + macdefine(mac, A_TEMP, macid("{cert_md5}"), md5h); + } + else + macdefine(mac, A_TEMP, macid("{cert_md5}"), ""); + } + else + { + macdefine(mac, A_PERM, macid("{cert_subject}"), ""); + macdefine(mac, A_PERM, macid("{cert_issuer}"), ""); + macdefine(mac, A_PERM, macid("{cn_subject}"), ""); + macdefine(mac, A_PERM, macid("{cn_issuer}"), ""); + macdefine(mac, A_TEMP, macid("{cert_md5}"), ""); + } + switch (SSL_get_verify_result(ssl)) + { + case X509_V_OK: + if (cert != NULL) + { + s = "OK"; + r = TLS_AUTH_OK; + } + else + { + s = certreq ? "NO" : "NOT", + r = TLS_AUTH_NO; + } + break; + default: + s = "FAIL"; + r = TLS_AUTH_FAIL; + break; + } + macdefine(mac, A_PERM, macid("{verify}"), s); + if (cert != NULL) + X509_free(cert); + + /* do some logging */ + if (LogLevel > 8) + { + char *vers, *s1, *s2, *cbits, *algbits; + + vers = macget(mac, macid("{tls_version}")); + cbits = macget(mac, macid("{cipher_bits}")); + algbits = macget(mac, macid("{alg_bits}")); + s1 = macget(mac, macid("{verify}")); + s2 = macget(mac, macid("{cipher}")); + + /* XXX: maybe cut off ident info? */ + sm_syslog(LOG_INFO, NOQID, + "STARTTLS=%s, relay=%.100s, version=%.16s, verify=%.16s, cipher=%.64s, bits=%.6s/%.6s", + who, + host == NULL ? "local" : host, + vers, s1, s2, /* sm_snprintf() can deal with NULL */ + algbits == NULL ? "0" : algbits, + cbits == NULL ? "0" : cbits); + if (LogLevel > 11) + { + /* + ** Maybe run xuntextify on the strings? + ** That is easier to read but makes it maybe a bit + ** more complicated to figure out the right values + ** for the access map... + */ + + s1 = macget(mac, macid("{cert_subject}")); + s2 = macget(mac, macid("{cert_issuer}")); + sm_syslog(LOG_INFO, NOQID, + "STARTTLS=%s, cert-subject=%.128s, cert-issuer=%.128s", + who, s1, s2); + } + } + return r; +} +/* +** ENDTLS -- shutdown secure connection +** +** Parameters: +** ssl -- SSL connection information. +** side -- server/client (for logging). +** +** Returns: +** success? (EX_* code) +*/ + +int +endtls(ssl, side) + SSL *ssl; + char *side; +{ + int ret = EX_OK; + + if (ssl != NULL) + { + int r; + + if ((r = SSL_shutdown(ssl)) < 0) + { + if (LogLevel > 11) + { + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS=%s, SSL_shutdown failed: %d", + side, r); + tlslogerr(side); + } + ret = EX_SOFTWARE; + } +# if !defined(OPENSSL_VERSION_NUMBER) || OPENSSL_VERSION_NUMBER > 0x0090602fL + + /* + ** Bug in OpenSSL (at least up to 0.9.6b): + ** From: Lutz.Jaenicke@aet.TU-Cottbus.DE + ** Message-ID: <20010723152244.A13122@serv01.aet.tu-cottbus.de> + ** To: openssl-users@openssl.org + ** Subject: Re: SSL_shutdown() woes (fwd) + ** + ** The side sending the shutdown alert first will + ** not care about the answer of the peer but will + ** immediately return with a return value of "0" + ** (ssl/s3_lib.c:ssl3_shutdown()). SSL_get_error will evaluate + ** the value of "0" and as the shutdown alert of the peer was + ** not received (actually, the program did not even wait for + ** the answer), an SSL_ERROR_SYSCALL is flagged, because this + ** is the default rule in case everything else does not apply. + ** + ** For your server the problem is different, because it + ** receives the shutdown first (setting SSL_RECEIVED_SHUTDOWN), + ** then sends its response (SSL_SENT_SHUTDOWN), so for the + ** server the shutdown was successfull. + ** + ** As is by know, you would have to call SSL_shutdown() once + ** and ignore an SSL_ERROR_SYSCALL returned. Then call + ** SSL_shutdown() again to actually get the server's response. + ** + ** In the last discussion, Bodo Moeller concluded that a + ** rewrite of the shutdown code would be necessary, but + ** probably with another API, as the change would not be + ** compatible to the way it is now. Things do not become + ** easier as other programs do not follow the shutdown + ** guidelines anyway, so that a lot error conditions and + ** compitibility issues would have to be caught. + ** + ** For now the recommondation is to ignore the error message. + */ + + else if (r == 0) + { + if (LogLevel > 15) + { + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS=%s, SSL_shutdown not done", + side); + tlslogerr(side); + } + ret = EX_SOFTWARE; + } +# endif /* !defined(OPENSSL_VERSION_NUMBER) || OPENSSL_VERSION_NUMBER > 0x0090602fL */ + SSL_free(ssl); + ssl = NULL; + } + return ret; +} + +# if !TLS_NO_RSA +/* +** TMP_RSA_KEY -- return temporary RSA key +** +** Parameters: +** s -- TLS connection structure +** export -- +** keylength -- +** +** Returns: +** temporary RSA key. +*/ + +# ifndef MAX_RSA_TMP_CNT +# define MAX_RSA_TMP_CNT 1000 /* XXX better value? */ +# endif /* ! MAX_RSA_TMP_CNT */ + +/* ARGUSED0 */ +static RSA * +tmp_rsa_key(s, export, keylength) + SSL *s; + int export; + int keylength; +{ +# if SM_CONF_SHM + extern int ShmId; + extern int *PRSATmpCnt; + + if (ShmId != SM_SHM_NO_ID && rsa_tmp != NULL && + ++(*PRSATmpCnt) < MAX_RSA_TMP_CNT) + return rsa_tmp; +# endif /* SM_CONF_SHM */ + + if (rsa_tmp != NULL) + RSA_free(rsa_tmp); + rsa_tmp = RSA_generate_key(RSA_KEYLENGTH, RSA_F4, NULL, NULL); + if (rsa_tmp == NULL) + { + if (LogLevel > 0) + sm_syslog(LOG_ERR, NOQID, + "STARTTLS=server, tmp_rsa_key: RSA_generate_key failed!"); + } + else + { +# if SM_CONF_SHM +# if 0 + /* + ** XXX we can't (yet) share the new key... + ** The RSA structure contains pointers hence it can't be + ** easily kept in shared memory. It must be transformed + ** into a continous memory region first, then stored, + ** and later read out again (each time re-transformed). + */ + + if (ShmId != SM_SHM_NO_ID) + *PRSATmpCnt = 0; +# endif /* 0 */ +# endif /* SM_CONF_SHM */ + if (LogLevel > 9) + sm_syslog(LOG_ERR, NOQID, + "STARTTLS=server, tmp_rsa_key: new temp RSA key"); + } + return rsa_tmp; +} +# endif /* !TLS_NO_RSA */ +/* +** APPS_SSL_INFO_CB -- info callback for TLS connections +** +** Parameters: +** s -- TLS connection structure +** where -- state in handshake +** ret -- return code of last operation +** +** Returns: +** none. +*/ + +static void +apps_ssl_info_cb(s, where, ret) + SSL *s; + int where; + int ret; +{ + int w; + char *str; + BIO *bio_err = NULL; + + if (LogLevel > 14) + sm_syslog(LOG_INFO, NOQID, + "STARTTLS: info_callback where=0x%x, ret=%d", + where, ret); + + w = where & ~SSL_ST_MASK; + if (bio_err == NULL) + bio_err = BIO_new_fp(stderr, BIO_NOCLOSE); + + if (bitset(SSL_ST_CONNECT, w)) + str = "SSL_connect"; + else if (bitset(SSL_ST_ACCEPT, w)) + str = "SSL_accept"; + else + str = "undefined"; + + if (bitset(SSL_CB_LOOP, where)) + { + if (LogLevel > 12) + sm_syslog(LOG_NOTICE, NOQID, + "STARTTLS: %s:%s", + str, SSL_state_string_long(s)); + } + else if (bitset(SSL_CB_ALERT, where)) + { + str = bitset(SSL_CB_READ, where) ? "read" : "write"; + if (LogLevel > 12) + sm_syslog(LOG_NOTICE, NOQID, + "STARTTLS: SSL3 alert %s:%s:%s", + str, SSL_alert_type_string_long(ret), + SSL_alert_desc_string_long(ret)); + } + else if (bitset(SSL_CB_EXIT, where)) + { + if (ret == 0) + { + if (LogLevel > 7) + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS: %s:failed in %s", + str, SSL_state_string_long(s)); + } + else if (ret < 0) + { + if (LogLevel > 7) + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS: %s:error in %s", + str, SSL_state_string_long(s)); + } + } +} +/* +** TLS_VERIFY_LOG -- log verify error for TLS certificates +** +** Parameters: +** ok -- verify ok? +** ctx -- x509 context +** +** Returns: +** 0 -- fatal error +** 1 -- ok +*/ + +static int +tls_verify_log(ok, ctx) + int ok; + X509_STORE_CTX *ctx; +{ + SSL *ssl; + X509 *cert; + int reason, depth; + char buf[512]; + + cert = X509_STORE_CTX_get_current_cert(ctx); + reason = X509_STORE_CTX_get_error(ctx); + depth = X509_STORE_CTX_get_error_depth(ctx); + ssl = (SSL *) X509_STORE_CTX_get_ex_data(ctx, + SSL_get_ex_data_X509_STORE_CTX_idx()); + + if (ssl == NULL) + { + /* internal error */ + sm_syslog(LOG_ERR, NOQID, + "STARTTLS: internal error: tls_verify_cb: ssl == NULL"); + return 0; + } + + X509_NAME_oneline(X509_get_subject_name(cert), buf, sizeof buf); + sm_syslog(LOG_INFO, NOQID, + "STARTTLS: cert verify: depth=%d %s, state=%d, reason=%s", + depth, buf, ok, X509_verify_cert_error_string(reason)); + return 1; +} +/* +** TLS_VERIFY_CB -- verify callback for TLS certificates +** +** Parameters: +** ctx -- x509 context +** +** Returns: +** accept connection? +** currently: always yes. +*/ + +static int +tls_verify_cb(ctx) + X509_STORE_CTX *ctx; +{ + int ok; + + ok = X509_verify_cert(ctx); + if (ok == 0) + { + if (LogLevel > 13) + return tls_verify_log(ok, ctx); + return 1; /* override it */ + } + return ok; +} +/* +** TLSLOGERR -- log the errors from the TLS error stack +** +** Parameters: +** who -- server/client (for logging). +** +** Returns: +** none. +*/ + +void +tlslogerr(who) + char *who; +{ + unsigned long l; + int line, flags; + unsigned long es; + char *file, *data; + char buf[256]; +# define CP (const char **) + + es = CRYPTO_thread_id(); + while ((l = ERR_get_error_line_data(CP &file, &line, CP &data, &flags)) + != 0) + { + sm_syslog(LOG_WARNING, NOQID, + "STARTTLS=%s: %lu:%s:%s:%d:%s", who, es, + ERR_error_string(l, buf), + file, line, + bitset(ERR_TXT_STRING, flags) ? data : ""); + } +} +#endif /* STARTTLS */ |
