diff options
Diffstat (limited to 'crypto/x509/x509_vfy.c')
-rw-r--r-- | crypto/x509/x509_vfy.c | 226 |
1 files changed, 149 insertions, 77 deletions
diff --git a/crypto/x509/x509_vfy.c b/crypto/x509/x509_vfy.c index 136bfbd..16db4c0 100644 --- a/crypto/x509/x509_vfy.c +++ b/crypto/x509/x509_vfy.c @@ -151,11 +151,11 @@ static int x509_subject_cmp(X509 **a, X509 **b) int X509_verify_cert(X509_STORE_CTX *ctx) { - X509 *x, *xtmp, *chain_ss = NULL; + X509 *x, *xtmp, *xtmp2, *chain_ss = NULL; int bad_chain = 0; X509_VERIFY_PARAM *param = ctx->param; int depth, i, ok = 0; - int num; + int num, j, retry; int (*cb) (int xok, X509_STORE_CTX *xctx); STACK_OF(X509) *sktmp = NULL; if (ctx->cert == NULL) { @@ -224,85 +224,118 @@ int X509_verify_cert(X509_STORE_CTX *ctx) break; } + /* Remember how many untrusted certs we have */ + j = num; /* * at this point, chain should contain a list of untrusted certificates. * We now need to add at least one trusted one, if possible, otherwise we * complain. */ - /* - * Examine last certificate in chain and see if it is self signed. - */ - - i = sk_X509_num(ctx->chain); - x = sk_X509_value(ctx->chain, i - 1); - if (ctx->check_issued(ctx, x, x)) { - /* we have a self signed certificate */ - if (sk_X509_num(ctx->chain) == 1) { - /* - * We have a single self signed certificate: see if we can find - * it in the store. We must have an exact match to avoid possible - * impersonation. - */ - ok = ctx->get_issuer(&xtmp, ctx, x); - if ((ok <= 0) || X509_cmp(x, xtmp)) { - ctx->error = X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT; - ctx->current_cert = x; - ctx->error_depth = i - 1; - if (ok == 1) - X509_free(xtmp); - bad_chain = 1; - ok = cb(0, ctx); - if (!ok) - goto end; + do { + /* + * Examine last certificate in chain and see if it is self signed. + */ + i = sk_X509_num(ctx->chain); + x = sk_X509_value(ctx->chain, i - 1); + if (ctx->check_issued(ctx, x, x)) { + /* we have a self signed certificate */ + if (sk_X509_num(ctx->chain) == 1) { + /* + * We have a single self signed certificate: see if we can + * find it in the store. We must have an exact match to avoid + * possible impersonation. + */ + ok = ctx->get_issuer(&xtmp, ctx, x); + if ((ok <= 0) || X509_cmp(x, xtmp)) { + ctx->error = X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT; + ctx->current_cert = x; + ctx->error_depth = i - 1; + if (ok == 1) + X509_free(xtmp); + bad_chain = 1; + ok = cb(0, ctx); + if (!ok) + goto end; + } else { + /* + * We have a match: replace certificate with store + * version so we get any trust settings. + */ + X509_free(x); + x = xtmp; + (void)sk_X509_set(ctx->chain, i - 1, x); + ctx->last_untrusted = 0; + } } else { /* - * We have a match: replace certificate with store version so - * we get any trust settings. + * extract and save self signed certificate for later use */ - X509_free(x); - x = xtmp; - (void)sk_X509_set(ctx->chain, i - 1, x); - ctx->last_untrusted = 0; + chain_ss = sk_X509_pop(ctx->chain); + ctx->last_untrusted--; + num--; + j--; + x = sk_X509_value(ctx->chain, num - 1); } - } else { - /* - * extract and save self signed certificate for later use - */ - chain_ss = sk_X509_pop(ctx->chain); - ctx->last_untrusted--; - num--; - x = sk_X509_value(ctx->chain, num - 1); } - } - - /* We now lookup certs from the certificate store */ - for (;;) { - /* If we have enough, we break */ - if (depth < num) - break; - - /* If we are self signed, we break */ - if (ctx->check_issued(ctx, x, x)) - break; - - ok = ctx->get_issuer(&xtmp, ctx, x); + /* We now lookup certs from the certificate store */ + for (;;) { + /* If we have enough, we break */ + if (depth < num) + break; + /* If we are self signed, we break */ + if (ctx->check_issued(ctx, x, x)) + break; + ok = ctx->get_issuer(&xtmp, ctx, x); + if (ok < 0) + return ok; + if (ok == 0) + break; + x = xtmp; + if (!sk_X509_push(ctx->chain, x)) { + X509_free(xtmp); + X509err(X509_F_X509_VERIFY_CERT, ERR_R_MALLOC_FAILURE); + return 0; + } + num++; + } - if (ok < 0) - return ok; - if (ok == 0) - break; + /* + * If we haven't got a least one certificate from our store then check + * if there is an alternative chain that could be used. We only do this + * if the user hasn't switched off alternate chain checking + */ + retry = 0; + if (j == ctx->last_untrusted && + !(ctx->param->flags & X509_V_FLAG_NO_ALT_CHAINS)) { + while (j-- > 1) { + xtmp2 = sk_X509_value(ctx->chain, j - 1); + ok = ctx->get_issuer(&xtmp, ctx, xtmp2); + if (ok < 0) + goto end; + /* Check if we found an alternate chain */ + if (ok > 0) { + /* + * Free up the found cert we'll add it again later + */ + X509_free(xtmp); - x = xtmp; - if (!sk_X509_push(ctx->chain, x)) { - X509_free(xtmp); - X509err(X509_F_X509_VERIFY_CERT, ERR_R_MALLOC_FAILURE); - return 0; + /* + * Dump all the certs above this point - we've found an + * alternate chain + */ + while (num > j) { + xtmp = sk_X509_pop(ctx->chain); + X509_free(xtmp); + num--; + ctx->last_untrusted--; + } + retry = 1; + break; + } + } } - num++; - } - - /* we now have our chain, lets check it... */ + } while (retry); /* Is last certificate looked up self signed? */ if (!ctx->check_issued(ctx, x, x)) { @@ -1604,47 +1637,84 @@ int X509_cmp_time(const ASN1_TIME *ctm, time_t *cmp_time) ASN1_TIME atm; long offset; char buff1[24], buff2[24], *p; - int i, j; + int i, j, remaining; p = buff1; - i = ctm->length; + remaining = ctm->length; str = (char *)ctm->data; + /* + * Note that the following (historical) code allows much more slack in the + * time format than RFC5280. In RFC5280, the representation is fixed: + * UTCTime: YYMMDDHHMMSSZ + * GeneralizedTime: YYYYMMDDHHMMSSZ + */ if (ctm->type == V_ASN1_UTCTIME) { - if ((i < 11) || (i > 17)) + /* YYMMDDHHMM[SS]Z or YYMMDDHHMM[SS](+-)hhmm */ + int min_length = sizeof("YYMMDDHHMMZ") - 1; + int max_length = sizeof("YYMMDDHHMMSS+hhmm") - 1; + if (remaining < min_length || remaining > max_length) return 0; memcpy(p, str, 10); p += 10; str += 10; + remaining -= 10; } else { - if (i < 13) + /* YYYYMMDDHHMM[SS[.fff]]Z or YYYYMMDDHHMM[SS[.f[f[f]]]](+-)hhmm */ + int min_length = sizeof("YYYYMMDDHHMMZ") - 1; + int max_length = sizeof("YYYYMMDDHHMMSS.fff+hhmm") - 1; + if (remaining < min_length || remaining > max_length) return 0; memcpy(p, str, 12); p += 12; str += 12; + remaining -= 12; } if ((*str == 'Z') || (*str == '-') || (*str == '+')) { *(p++) = '0'; *(p++) = '0'; } else { + /* SS (seconds) */ + if (remaining < 2) + return 0; *(p++) = *(str++); *(p++) = *(str++); - /* Skip any fractional seconds... */ - if (*str == '.') { + remaining -= 2; + /* + * Skip any (up to three) fractional seconds... + * TODO(emilia): in RFC5280, fractional seconds are forbidden. + * Can we just kill them altogether? + */ + if (remaining && *str == '.') { str++; - while ((*str >= '0') && (*str <= '9')) - str++; + remaining--; + for (i = 0; i < 3 && remaining; i++, str++, remaining--) { + if (*str < '0' || *str > '9') + break; + } } } *(p++) = 'Z'; *(p++) = '\0'; - if (*str == 'Z') + /* We now need either a terminating 'Z' or an offset. */ + if (!remaining) + return 0; + if (*str == 'Z') { + if (remaining != 1) + return 0; offset = 0; - else { + } else { + /* (+-)HHMM */ if ((*str != '+') && (*str != '-')) return 0; + /* Historical behaviour: the (+-)hhmm offset is forbidden in RFC5280. */ + if (remaining != 5) + return 0; + if (str[1] < '0' || str[1] > '9' || str[2] < '0' || str[2] > '9' || + str[3] < '0' || str[3] > '9' || str[4] < '0' || str[4] > '9') + return 0; offset = ((str[1] - '0') * 10 + (str[2] - '0')) * 60; offset += (str[3] - '0') * 10 + (str[4] - '0'); if (*str == '-') @@ -1921,6 +1991,8 @@ X509_STORE_CTX *X509_STORE_CTX_new(void) void X509_STORE_CTX_free(X509_STORE_CTX *ctx) { + if (!ctx) + return; X509_STORE_CTX_cleanup(ctx); OPENSSL_free(ctx); } |